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CROSS REFERENCE TO RELATED APPLICATION
This application is related to a co-pending application of Anton Brunner, Ser. No. 151,737, filed May 20, 1980.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a radar antenna, designed as a pillbox antenna, and more particularly to such an antenna which has a secondary radar antenna or Identification-Friend-Foe (IFF) antenna integrated therewith.
2. Description of the Prior Art
Primary radar antennas and IFF antennas can be designed to be structurall separate, for example, in the form of a pillbox antenna and an IFF bar antenna, and can then be combined, for example, spatially above one another. Also, a bar antenna with a series-fed radar antenna and an integrated IFF bar antenna is known in the art. The disadvantage of a series-fed radar antenna, for example, a waveguide slot antenna, is in its narrow-band characteristics and, in particular, in the frequency-dependency of the direction of maximum radiation.
SUMMARY OF THE INVENTION
It is therefore the object of the present invention to provide a very compact, low radar antenna comprising an integrated IFF antenna, which is suitable for accommodation on small vehicles, and which exhibits optimum properties in the horizontal plane within a large frequency bandwidth.
According to the invention, the above object is achieved by providing that the IFF antenna is a radiator group composed of a plurality of radiator elements, the group being mounted in the upper side of a pillbox antenna.
As is known, a simple pillbox antenna is formed by a cylindrical parabolic reflector and two metallic plates which are perpendicular to the reflector and which extend parallel to one another spaced apart a distance of less than 1 wavelength. The feed of such an antenna takes place at the focal line. A fan-shaped radiation lobe results.
The pillbox antenna for the radar signals can also be designed in a bilevel manner in accordance with a further development of the invention. Such a bilevel or folded pill-box antenna which is known per se, comprises a cylindrical parabolic reflector and two metallic plates perpendicular to the reflector and extending parallel to one another, with an intermediate plate extending parallel to these two plates, but not extending to the parabolic reflector. On both sides of the intermediate plate inter-plate spaces result. The radar signal primary radiator is arranged with its radiation center in the focal line of the cylindrical parabolic reflector in the lower inter-plate space. Along the cylindrical parabolic reflector an insulation for deflecting the radiation from one inter-plate space into the other is provided. Such a bilevel pillbox antenna therefore exhibits the advantage that the aperture does not become partially shadowed by the primary radiator.
The radiator elements of the IFF antenna can be arranged in a single row or in two rows extending parallel to one another, in particular, in such a manner that the multiple antenna operates as an end-on or end-fire directional array. The radiator elements can then be formed, for example, by slots which are secured in a metallic surface extending at least approximately parallel to the upper side of the pillbox antenna, and thus form a flat top or planar antenna. The slots can be energized by a microstrip line, such as a triplate line, so that the phase at the slots causes a virtually tangential direction of maximum radiation. In the framework of the microstrip transmission line, a circuit for the formation of the sum and difference signals from the signals of the two IFF radiators, formed by two rows of slots, is advantageously provided. Apparatus may also be provided for changing the angle of inclination between the flat top antenna and the upper side of the pillbox antenna so that the direction of maximum radiation of the IFF antenna can be adjusted with respect to the angle of elevation.
Instead of slots, the radiator elements can also be realized by unipole rods mounted perpendicularly on the upper side of the pillbox antenna, of which rods, in every row, only one is fed and the remainder are parasitic radiator elements. The unipole feed, as well as a circuit for the formation of the sum and difference signals from the signals of the two IFF radiators, formed by two unipole rod rows, can be realized by means of a coaxial line integrated in the housing of the pillbox antenna.
The radiator elements of the IFF antenna can also be arranged in a single row, in particular, in such a fashion that the multiple antenna operates as a broadside array. The radiator elements in this instance can likewise be realized by unipole rods mounted perpendiculary on the surface on the pillbox antenna, which, however, are fed in parallel. In order to shield the rear region, a reflector wall is advantageously provided perpendicularly to the pillbox housing behind the transversely radiating broadside array. The unipole rod feed, as well as, in the case of a subdivision of the multiple antenna into a left sub-group and into a right sub-group, also a circuit for the formation of the sum and difference signals from the signals of the two IFF radiators formed by the two sub-groups can be realized by a coaxial line integrated in the housing of the pillbox antenna.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects, features and advantages of the invention, its organization, construction and operation will be best understood from the following detailed description, taken in conjunction with the accompanying drawings, on which:
FIG. 1 is a plan view of an integrated antenna structure including a bilevel pillbox antenna for primary radar signals and an IFF flat top antenna for secondary radar signals, constructed in accordance with the present invention;
FIG. 2 is a sectional view taken substantially along the line II--II of FIG. 1;
FIG. 3 is a plan view of a bilevel pillbox antenna and an IFF antenna constructed in accordance with another embodiment of the invention;
FIG. 4 is a sectional view taken substantially along the line IV--IV of FIG. 3;
FIG. 5 is a plan view of another embodiment of a bilevel pillbox antenna and an IFF antenna constructed in accordance with the present invention; and
FIG. 6 is a sectional view taken substantially along the line VI--VI of FIG. 5.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1 and 2, a bilevel pillbox antenna comprises a cylindrical parabolic reflector 1 and two metallic plates 2 and 3 arranged perpendicular to the reflector 1 and extending parallel to one another, with an intermediate plate 4 therebetween which does not extend to the parabolic reflector 1. The intermediate plate 4 extends parallel to the two plates 2 and 3. On each side of the intermediate plate 4 an interplate space 5, 6 results. In the focal line of the parabolic reflector 1 a radar signal primary radiator 7 is arranged with its radiation center in the interplate space 5. The radar signal primary radiator 7 can be designed, for example, as an open waveguide or as a small horn-type radiator, for example a deflection horn-type radiator as is illustrated in FIGS. 1-6. The radar signal coming from a supply 8 is thus coupled into the interplate space 5 by way of the primary radiator 7. The radiation transition from the lower interplate space 5 into the upper interplate space 6 occurs, in the arrangement illustrated in FIGS. 1 and 2, with the aid of two 45° surfaces 9 and 10 in the cross-sectional profile of the cylindrical parabolic reflector 1. The radiation deflection can also occur by the provision of a simple slot between the intermediate plate 4 and the cylindrical parabolic reflector 1. The intermediate plate 4 can be mounted, for example, in a support mount comprising dielectric material extending along the cylindrical parabolic reflector 1. Such a support mount of the intermediate plate 4 may be preferred to the utilization of discrete spacing pins, since, through such pins, interfering inhomogeneity locations can occur. Before the aperture of the upper interplate space 6, a funnel-shaped opening 11 is provided in order to render possible the desired beaming of the radar signal radiation. The lower interplate space 5 is closed off with a metallic wall 12 on the side which faces away from the cylindrical parabolic reflector 1.
An IFF antenna integrated with the primary radar antenna is secured on an upper plate 3 as a flat top antenna 13 on the pillbox antenna. In the flat top antenna 13, two mutually parallel extending rows of slots 14, 15, 16 and 17, 18, 19 are provided, the slots extending transversely to the direction of maximum radiation of the pillbox antenna. The slots 14-19 are energized by a triplate line or a microstrip line 20, 21, such that their phase brings about a virtually tangential direction of maximum radiation. Within the framework of the microstrip transmission line, a circuit 22 is provided for the formation of the sum and difference signals from the signals of the IFF radiators formed by the two rows of slots. An apparatus for changing the angle of incidence δ between the flat top antenna 13 and the upper side of the pillbox antenna makes it possible to provide different inclinations of the flat top antenna 13, so that the direction of maximum radiation can be adjusted. In the pillbox housing, feed lines are provided for feeding the sum and difference signals for the circuit 22. Due to the end-on directional array characteristic which results from the axial arrangement of the radiating elements, i.e. the slots 14-19, the IFF major lobe is more strongly beamed not only in the horizontal plane, but also in the vertical plane.
The integrated primary radar/IFF antenna, illustrated in FIGS. 3 and 4, comprises, for the radiation of primary radar signals, a pillbox antenna which corresponds to that of FIGS. 1 and 2. Therefore, a detailed description thereof will be omitted. The radiator elements of the IFF antenna are formed by unipole rods 24-31, mounted perpendicularly on the upper side of the pillbox antenna. The rods 24-27 are arranged in one row and the rods 28-31 are arranged in another row parallel thereto. In each row only one unipole rod 26 or 30, respectively, is fed. The remaining unipole rods are only parasitic radiator elements with suitable distances and lengths and serve as directors 24, 25 and 28, 29, and reflectors 27, 31, for the purpose of increasing the directional effect. The feed of the unipole rods 26 and 30 occurs by way of a coaxial line 32 integrated in the pillbox housing. In addition, a circuit 33 for forming the sum and difference signals from the signals of the two IFF radiators formed by the two unipole rod rows is provided, the circuit 33 being likewise formed by a coaxial line integrated in the housing of the pillbox antenna. As a mechanical and climatic protection, for example, a synthetic cover (radome) 34 can be applied over all of the rods 24-31, or in a thin-like fashion, separate covers can be applied over the rows of rods, respectively. Also the IFF antenna, integrated corresponding FIGS. 3 and 4, which is constructed as a Yagi-like unipole array, exhibits an end-on directional characteristic and beams the major lobe in both planes.
The embodiment illustrated in FIGS. 5 and 6 exhibits, for the purpose of primary radar signal radiation, a bilevel pillbox antenna which corresponds to that according to FIGS. 1 and 2. Therefore, description of this structure is not necessary. The radiator elements of the integrated IFF antenna are formed by unipole rods 34-42 which are mounted perpendicularly on the surface of the pillbox antenna. The rods are arranged in a single row, in particular in such a manner that the multipe antenna operates as a broadside array (or transverse radiator). The multiple antenna is here separated into a left component sub-group and into a right component sub-group. The left component sub-group comprises the unipole rods 35-38, while the right component sub-group comprises the unipole rods 39-42. The feed for the unipole rods 35-42 occurs on a parallel basis. The unipole feed, as well as a circuit for the formation of the sum and difference signals 43 from the signals of the two IFF radiators formed by the two component sub-groups, are realized by way of a coaxial line 44 which is integrated in the housing of the pillbox antenna. Behind the unipole rods 35- 42 a reflector wall 45 is provided, standing perpendicuarly on the pillbox housing, and serving the purpose of shielding the rear region. In order to cover the unipoe rods 35-42, and also the opening 11 of the pillbox antenna, a radome 46 is provided, the radome being mounted on its one side on the upwardly projecting end of the reflector 45.
It should be additionally pointed out that, in the case of all exemplary embodiments of integrated primary radar/IFF antennas in accordance with the present invention, which are illustrated in FIGS. 1-6, instead of the bilevel pillbox antenna for radiating the primary radar signals, also a simple pillbox antenna can be employed; however, the above-mentioned advantages of the bilevel pillbox antenna will no longer be available.
Although I have described my invention by reference to particular illustrative embodiments thereof, many changes and modifications of the invention may become apparent to those skilled in the art without departing from the spirit and scope of the invention. I therefore intended to include within the patent warranted hereon all such changes and modifications as may reasonably and properly be included within the scope of my contribution to the art. | A primary radar antenna, designed as a pillbox antenna, has an IFF antenna integrated therewith. Excellent properties with regard to compactness, radiation and frequency dependency are achieved through the combination of a pillbox antenna with a multiple IFF antenna composed of a plurality of radiator elements, which is applied on the upper side of the pillbox antenna for radiation of the IFF signals. The antenna is particularly suitable as a combined primary radar/IFF antenna for smaller vehicles. | 7 |
BACKGROUND OF THE INVENTION
[0001] Semiconductor processing technology nowadays allows complex systems to be integrated on one single chip. A consistent system design technology is in great need to cope with such complexity and with the ever shortening time-to-market requirements (B. Tuck Raise your sights to the system level—design report: '97 paris forum (round-table discussion). Computer Design, pp. 53-74, June 1997 ). It should allow to map these applications cost-efficiently to the target realisation while meeting all real-time and other constraints.
[0002] The target applications of our task-level system synthesis approach are advanced real-time multi-media and information processing (RMP) systems, such as consumer multi-media electronics and personal communication systems. These applications involve a combination of complex data- and control-flow where complex data types are manipulated and transferred. Most of these applications are implemented with compact and portable devices, putting stringent constraints on the degree of integration (i.e. chip area) and on their power consumption. Secondly, these systems are extremely heterogeneous in nature and combine high performance data processing (e.g. data processing on transmission data input) as well as slow rate control processing (e.g. system control functions), synchronous as well as asynchronous parts, analog versus digital, and so on. Thirdly, time-to-market has become a critical factor in the design phase. Finally, these systems are subjected to stringent real-time constraints (both hard and soft deadlines are present), complicating their implementation considerably. The platform for these applications include one or more programmable components, augmented with some specialized data paths or co-processors (accelerators).
[0003] The programmable components run software components, being slow to medium speed algorithms, while time-critical parts are executed on dedicated hardware accelerators.
[0004] When looking at contemporary design practices for mapping software (and hardware) on such a platform, one can only conclude that these systems nowadays are designed in a very ad hoc manner (F. Thoen, F. Catthoor, “Modeling, Verification and Exploration of Task-level Concurrency in Real-Time Embedded Systems”, ISBN 0-7923-7737-0, Kluwer Acad. Publ., Boston, 1999. ) The design trajectory starts by identifying the global specification entities that functionally belong together, called tasks or processes. This step is followed by a manual ‘hardware-software partitioning’. Because of separate implementation of the different tasks and of the software and hardware, afterwards a system integration step is inevitable. This manual step performs the ‘system/software embedding’ and synthesizes the interface hardware, which closes the gap between the software and the hardware component.
[0005] The main goal of system/software embedding is to encapsulate the concurrent tasks in a control shell which takes care of the task scheduling (software scheduling in the restricted sense) and the inter-task communication. Task scheduling is an error-prone process that requires computer assistance to consider the many interactions between constraints. Unfortunately, current design practices for reactive real-time systems are ad hoc and not very retargetable. Designers have used real-time operating systems (RTOS) or kernels to solve some of these scheduling problems. Both of RTOSs and kernels assume a specific processor and a particular I/O configuration. Such practices result in poor modularity and limited retargetability, thus severely discourage exploitation of the co-design space. This is the case even if the program is written in a high-level language. Moreover, these RTOSs in fact only provide limited support for real-timeness, and leave satisfaction of the timing constraints to the designer. They can be considered as nothing more than an optimized back-end for performing the task scheduling, and typically they are not integrated in a design framework in which a global specification model serves as entry point.
[0006] Existing approaches we will work neither at the detailed white-box task model (see e.g. P. Eles, K. Kuchcinski, Z. Peng, A. Doboli, P. Pop, “Scheduling of conditional process graphs for the synthesis of embedded systems”, Proc. 1 st ACM/IEEE Design and Test in Europe Conf., Paris, France, pp.132-138, February 1998. P. Hoang, J. Rabaey, “Scheduling of DSP programs onto multiprocessors for maximum throughput”, IEEE Trans. on Signal Processing, Vol.SP-41, No.6, pp.2225-2235, June 1993. ) where all the operations are considered already during the mapping and where too much information is present to allow a thorough exploration, nor at the black-box task model (see e.g. S. Ha, E. Lee, “Compile-time scheduling of dynamic constructs in dataflow program graphs”, IEEE Trans. on Computers, Vol.C-47, No.7, pp.768-778, July 1997. I. Hong, M. Potkonja, M. Srivastava, “On-line scheduling of hard real-time tasks on variable voltage processor”, Proc. IEEE Int. Conf. on Comp. Aided Design, Santa Clara Calif., pp.653-656, Nov. 1998. Y. Li, W. Wolf, “Scheduling and allocation of single-chip multi-processors for multimedia”, Proc. IEEE Wsh. on Signal Processing Systems ( SIPS ), Leicester, UK, pp.97-106, November 1997. where insufficient information is available to accurately steer even the most crucial cost trade-offs.
[0007] Other work P. Eles, K. Kuchcinski, Z. Peng, A. Doboli, P. Pop, “Scheduling of conditional process graphs for the synthesis of embedded systems”, Proc. 1 st ACM/IEEE Design and Test in Europe Conf ., Paris, France, pp.132-138, February 1998. ) considers task scheduling as a separate issue from cost. In their work, the assignment to processors with different power or varying supply voltage is either “automatic”, i.e., without trade-off between timing and cost, e.g., the processor energy costs, or not treated.
AIM OF THE INVENTION
[0008] It is the aim of the invention to present an approach for management of concurrent tasks as part of a system level hardware-software codesign being capable of exploring both timing and processor cost issues with a reasonable complexity.
SUMMARY OF THE INVENTION
[0009] It is an aspect of the invention to incorporate in the design steps of an essentially digital system a two-level scheduling approach. In said approach said description describes the functionality and timing aspects of said digital system and comprises of a set of or plurality of communicating tasks while each of said tasks comprise of a set of or a plurality of nodes. With two-level scheduling approach is meant that first for at least one of said tasks its nodes are scheduled. When scheduling of at least one of said tasks is performed, scheduling of tasks itself is performed. In an embodiment of said two-level scheduling approach scheduling within tasks, thus of task nodes can be denoted static scheduling. Said task scheduling can be denoted dynamic scheduling. The terminology static and dynamic finds its origin in the fact that the so-called grey-box is constructed by placing deterministic, thus rather static behavior in nodes while non-deterministic behavior, thus rather dynamic behavior, is placed in tasks. In an embodiment of said two-level scheduling approach said scheduling within tasks, thus of task nodes includes besides time constraints also cost optimization, more in particular said cost is related to the processors on which said task nodes are executed. Said two-level scheduling includes thus besides ordening of said task nodes, being a typical output of scheduling, also assignment of task nodes to processors. In said two-level scheduling a concurrent architecture with a set or a plurality of processors is assumed. Examples are given for two processor architectures below but the invention is not limited thereto. In an embodiment of said two-level scheduling approach said static scheduling results in a plurality of partial static scheduled description. Said partial static scheduled descriptions or partial static schedule options are further exploited in said dynamic scheduling, meaning that said dynamic scheduling performs a step of selecting for said tasks one of said partial static schedules. Further design of said essentially digital system is then performed based on the partial scheduled description resulting from said dynamic scheduling step. Each static scheduling step generates cost-cycle budget trade-off curves which are exploite by said dynamic scheduling step. Alternatively one can state that said static scheduling step generates scheduling options, being different in cost and cycle budget, each option being related to a particular scheduling of nodes and allocation of nodes on processors. Said dynamic scheduling step selects for each of said tasks one of said options while guaranteeing that said options are compatible, meaning taking into account the limited resources or processors into account. It is an aspect of the invention to incorporate in the design steps of an essentially digital system a step of modifying a description of said essentially digital systems with task concurrency improvement transformations. Said description describes the functionality and timing aspects of said digital system and comprises of a set of or a plurality of communicating tasks while each of said tasks comprise of a set of or a plurality of nodes. The modifying step transforms a first or initial description into a second or improved description. Said transformation are aimed at improving the concurrency between said tasks. With concurrency is meant the ability to execute tasks at least partial in parallel. Often within said first or initial description hiddes that some tasks have concurrent behavior, menaing have the ability to be executed partially simultaneously. So hidding of concurrency is most often due to data dependencies. However often within said first description data dependencies which are not functionally necessary are introduced, thereby preventing concurrency of tasks unnessary. Said task concurrency improvement transformations comprises of a data dependency removing step while maintaining the functionality of the digital system, possibly by introducing some buffering, meaning introducing some storage space for data. It can be noted that although concurrency improvement of tasks is aimed at, said concurrency improvement steps can have as extra effect that concurrency of nodes within tasks is improved also. In an embodiment said task concurrency improvement transformations are used on said descriptions used in said two-level scheduling approach, more in particular before performing static scheduling. It is an aspect of the invention to recognize that task concurrency management should be performed early in the design flow for designing essentially digital system. With early is meant before hardware-software partitioning, thus before deciding which tasks will be performed by running software on a predefined processor (software implementation) and which tasks will be performed by the running of a dedicated custom, meaning further to be designed, processor. It must be noted that the processor representation used in the schedulings are only abstractions of the later fysical realisation of the system. The invention can be formalized as follows: A method for designing an essentially digital system, comprising the steps of:
[0010] 1. describing the functionality and timing of said digital system in a description being a set of (at least two) or a plurality of thread frames (also denoted tasks), each of said thread frames being a set of (at least two) or a plurality of thread nodes;
[0011] 2. generating a plurality of static schedulings for at least two of the thread nodes of one of said thread frames;
[0012] 3. performing a dynamic scheduling on at least two of said thread frames, said dynamic scheduling comprising of selecting for at least one of said thread frames one of said generated plurality of static schedulings, said dynamic scheduling resulting in an at least partial scheduled description; and
[0013] 4. designing said digital system from said at least partial scheduled description.
[0014] The method described above, wherein said essentially digital system being modelled as a set of or a plurality of processors and said generating of a plurality of static schedulings comprising solving of a first time-constraint cost optimization problem wherein thread nodes are assigned to said processors and said cost essentially being related to said processors. The method described above, wherein said generating of a plurality of static scheduling generates cost-cycle budget trade-off curves for at least two thread frames, said cost-cycle budget trade-off curves comprise of points representing said static schedulings. The method described above, wherein said dynamic scheduling comprises of a second time-constraint cost optimization problem. The method described above, wherein said first time-constraint cost optimization optimizes a cost function comprising at least energy consumption of a processor executing a scheduled thread node. The method described above, wherein said second time-constraint cost optimization optimizes a cost function comprising at least energy consumption of a processor Executing a scheduled thread node. The method described above, wherein said generating of static schedulings for a thread frame being capable of modifying the amount of thread nodes within said thread frame. The method describing above, wherein said tasks are communicating. The method described above, wherein non-deterministic behavior of said essentially digital system is described by the dynamical scheduling of the thread frames while the deterministic behavior is modelled inside the thread frames by the static scheduling of the thread nodes. The method described above wherein said designing step comprises the step of partitioning said at least partially scheduled description over a plurality of processors. The method describe above, wherein said designing step comprises the step of performing a hardware/software partitioning step on said at least partially scheduled description. The method described above, wherein before generating said plurality of static schedulings for at least one thread frame a task concurrency improving transformation on said thread frame is performed.
[0015] It is a first aspect of the invention to disclose a method for designing an essentially digital system, wherein Pareto-based task concurrency optimization is performed. Within said method a system-level description of the functionality and timing of said digital system, said system-level description comprising of a plurality of tasks, is generated. Task concurrency optimization is performed on said system-level description, thereby obtaining a task concurrency optimized system-level description, including Pareto-like task optimization information. Finally said essentially digital system is designed based on said task concurrency optimized system-level description.
[0016] It is a first embodiment of said first aspect to work with a grey-box description within said method.
[0017] It is a second embodiment of said first aspect to include within said task concurrency optimized system-level description a real-time operating system, exploiting said Pareto-like task optimization information.
[0018] It is a second aspect of the invention to disclose a method for designing an essentially digital system, wherein grey-box task concurrency optimization is performed. Within said method a description of the functionality and timing of said digital system is generated, said description being a grey-box system-level description comprising of a plurality of tasks. Task concurrency optimization is performed on said grey-box system-level description, thereby obtaining a task concurrency optimized grey-box system-level description. Finally said essentially digital system is designed based on said task concurrency optimized grey-box system-level description.
[0019] It is a first embodiment of said second aspect to work with a Pareto-based approach for optimization.
[0020] It is a second embodiment of said second aspect to include within said task concurrency optimized system-level description a real-time operating system.
[0021] It is an embodiment of said two aspects to use a grey-box description wherein non-deterministic behavior of said digital system is modeled by interacting of said tasks, while each of said tasks describe part of the deterministic behavior of said digital system.
[0022] It is an embodiment of said two aspects to use within said task concurrency optimization a design-time intra-task scheduling performing design-time intra-task scheduling for at least two of said tasks separately, thereby generating a plurality of intra-task schedules for each of said tasks. Said design-time intra-task scheduling is also denoted a first static scheduling.
[0023] In a further embodiment thereof said plurality of intra-task schedules is a subset of all possible intra-task schedules, said subset containing essentially only Pareto optimal schedules. This means that in terms of cost—constraint terms, these schedules are withheld with for a certain cost the minimal constraint and for a certain constraint minimal cost. The cost can be the power consumption needed while executing a task on said digital device or an estimate thereof. The constraint can be the time needed for execution of a task on said digital device or an estimate thereof. Said time is also denoted the cycle budget.
[0024] In a still further embodiment said digital system is assumed to have at least one processor and said design-time intra-task scheduling takes into account processor power consumption optimization.
[0025] In an alternative still further embodiment said digital system is assumed to comprise of a plurality of processors, said design-time intra-task scheduling takes into account processor power consumption optimization, including assignment of tasks to processors.
[0026] Hence said task concurrency optimization, and in particular the static or design-time scheduling part thereof, performs a pre-ordering within tasks under real-time constraints while minimizing processor operation costs.
[0027] In a particular implementation said static scheduling exploits a mixed integer linear programming (MILP) approach.
[0028] In an embodiment of these last two embodiments at least one processor is considered to be a multi supply voltage processor, with either fixed or variable supply voltages.
[0029] It is an embodiment of said two aspects of the invention to design after static scheduling a run-time scheduler, being part of a real-time operating system. Said scheduler is capable of performing dynamic scheduling of at least two of said tasks, said dynamic scheduling comprising of selection for at least one of said tasks one of said generated static schedules. Said dynamic scheduling selection is based on cost-constraint information of said generated static schedules. Hence said dynamic scheduling comprises of a second time-constraint cost optimization problem. Said second time-constraint cost optimization optimizes a cost function comprising at least energy consumption of a processor, executing a scheduled task.
[0030] In a particular implementation said dynamic scheduling exploits a constraint integer linear programming approach.
[0031] Within said two aspects of the invention the concept of tasks is defined as grouping of logical operations, functionally grouped together. With task is meant a real-time task, thus at least partly dynamically created or deleted. Said tasks are typically concurrent, interacting or communicating. A suitable grey-box description can be based on a MTG-CDFG model, wherein the multi-thread graph (MTG) is used for inter-task descriptions and the control data flow graph (CDFG) is used for intra-task descriptions. Said tasks concurrency optimization taking into account only part of the logical operations needed for describing the functionality and timing of said digital system. Said tasks are design-time analyzable parts of said grey-box description.
[0032] In an embodiment of the invention said grey-box system-level description comprise of a set of at least two or a plurality of tasks, also denoted thread frames, each of said thread frames being a set of at least two or a plurality of thread nodes. Said thread frame's or task's nodes comprise of logical operations, functionally belonging together.
[0033] Within such frame-node description said static or design-time scheduling generates a plurality of static schedulings of at least two of the thread nodes of one of said thread frames. When said essentially digital system is modeled as a set of or a plurality of processors, said generating of a plurality of static schedulings within a task comprising solving of a first time-constraint cost optimization problem wherein thread nodes are assigned to said processors and said cost essentially being related to said processors. Cost-cycle budget trade-off curves are generated for at least two thread frames, said cost-cycle budget trade-off curves comprise of a list of points representing part of all possible said static schedulings, said part being Pareto optimal schedulings in terms of the cost and cycle budget. Said generating of static schedulings for a thread frame can further be capable of modifying the amount of thread nodes within said thread frame.
[0034] The invented design method is a system-level design approach, meaning that said task concurrency optimization is performed before hardware/software co-design, hence before it is decided which task will be performed by dedicated hardware or be mapped on a programmable processor. Thus a final hardware/software co-design step follows after task concurrency optimization. Said co-design step will result in a final implementation, whereon a real-time operating system, including a run-time scheduler, using Pareto-like task optimization information for his scheduling activities.
[0035] In an embodiment of the invention wherein said grey-box description is obtained by performing task concurrency enabling steps on a first initial description or global specification of said digital system. Said task concurrency enabling steps include automatic grey-box description extraction, obtaining a first initial grey-box description or unified specification. Said task concurrency enabling steps include applying task concurrency improving transformations on said first initial grey-box description or unified specification, thereby obtaining said grey-box description being a task concurrency improved or enabled grey-box description.
[0036] In an alternative implementation before said task concurrency optimization dynamic memory management and/or task level DTSE transformations are performed.
BRIEF DESCRIPTION OF THE DRAWINGS
LIST OF FIGURES
[0037] [0037] 7 . 1 Prior Art
[0038] [0038] 7 . 2 TCM overview
[0039] [0039] 7 . 3 TCM run-time scheduler
[0040] [0040] 7 . 4 System layer of MPEG4 IM1 player, with several concurrent modules and complex dynamic control constructs
[0041] [0041] 7 . 5 System layer of MPEG4 IM1 player, with several concurrent modules and complex dynamic control constructs.
[0042] [0042] 7 . 6 Illustration of important grey-box model elements.
[0043] [0043] 7 . 7 A real-life example of a grey-box model extracted from system layer of the MPEG4 IM1-player.
[0044] [0044] 7 . 8 A global unified system design methodology covering different levels of abstraction with emphasis on the concurrent task related context.
[0045] [0045] 7 . 9 Global Pareto curve after TCM scheduling and processor allocation/assignment exploration
[0046] [0046] 7 . 10 Global Pareto curve after TCM concurrency extraction and transformations
[0047] [0047] 7 . 11 Selection of appropriate point on Pareto curves for TCM characterized task clusters, after entering a foreign task cluster from the network
[0048] [0048] 7 . 12 System level modules of the MPEG4 IM1 player
[0049] [0049] 7 . 13 Increasing the amount of concurrency by breaking data dependencies
[0050] [0050] 7 . 14 Comparison between scheduling the original and the transformed graphs
[0051] [0051] 7 . 15 Hierachical rewriting hides less important constructs for TCM
[0052] [0052] 7 . 16 Hierachical rewriting illustrated on IM1 player
[0053] [0053] 7 . 17 Hide undesired constructs without trade-off
[0054] [0054] 7 . 18 Code expansion creates freedom for scheduling
[0055] [0055] 7 . 19 Code expansion in IM1 (1)
[0056] [0056] 7 . 20 Code expansion in IM1 (2)
[0057] [0057] 7 . 21 Remove constructs that make concurrency analysis difficult
[0058] [0058] 7 . 22 Trade-off complexity/freedom must be taken into account (1)
[0059] [0059] 7 . 23 Trade-off complexity/freedom must be taken into account (2)
[0060] [0060] 7 . 24 Transform constructs that cannot be removed
[0061] [0061] 7 . 25 Concurrency analysis focuses on parallelism
[0062] [0062] 7 . 26 Remove unused or redundant code
[0063] [0063] 7 . 27 Weight-based hiding reduces complexity further with trade-off
[0064] [0064] 7 . 28 Partitioning clusters tasks with high interaction
[0065] [0065] 7 . 29 An example of a task graph
[0066] [0066] 7 . 30 Static scheduling result
[0067] [0067] 7 . 31 Dynamic scheduling of two example thread frame
[0068] [0068] 7 . 32 The dynamic scheduling of ADSL
[0069] [0069] 7 . 33 ADSL digital modem schematic
[0070] [0070] 7 . 34 Comparison between scheduling the initial and the second transformed graphs
[0071] [0071] 7 . 35 Examples of scheduling the second transformed graph
[0072] [0072] 7 . 36 The difference between case 1 and case 2
[0073] [0073] 7 . 37 All possible schedules of the timers in case 3
[0074] [0074] 7 . 38 DM oriented transformations illustrated on the input buffers of the IM1-player
[0075] [0075] 7 . 39 Constraints on the task-schedule reducing the DM requirements of a system
LIST OF TABLES
[0076] 7.1 Thread nodes performance
[0077] 7.2 Two example thread frames
[0078] 7.3 Assumption on processors
[0079] 7.4 Dead line and execution time of SW tasks
[0080] 7.5 Execution time and energy consumption in one TB, case 1
[0081] 7.6 Scheduling result, case 1
[0082] 7.7 Execution time and energy consumption in one TB, case 2
[0083] 7.8 Scheduling result, case 2
[0084] 7.9 Execution time and energy consumption in one TB, case 3
[0085] 7.10 Scheduling result, case 3
[0086] 7.11 Execution time and energy consumption in one TB, case 4
[0087] 7.12 Scheduling result, case 4
[0088] 7.13 Execution time and energy consumption in one TB, case 5
[0089] 7.14 Scheduling result, case 5
[0090] 7.15 Energy cost of different cases at different working voltages
[0091] 7.16 Energy cost of different cases at the same working voltages
[0092] 7.17 Execution times and processing energy of most important tasks in IM1-player on a heterogeneous platform with one and two hardware accelerators
[0093] 7.18 Memory requirements and memory energy of most important tasks in IM1-player on a heterogeneous platform with one and two hardware accelerators
DETAILED DESCRIPTION OF THE INVENTION
[0094] We will first give a broad overview of the steps that we have invented to solve the problems presented in the prior-art. Afterwards we will explain in more detail each of the steps: grey-box model extraction, transformations, static and dynamic scheduling.
[0095] 6.1 Overview
[0096] 6.1.1 Motivation
[0097] From the prior-art presented above, one can conclude that there is a lack of methodology and tool support at the system level for the co-design of hardware and software and for the task concurrency management, often resulting in an iterative and error-prone design cycle. At the top there is a need for an unified specification model with the power to represent system-level abstraction like task concurrency, dynamic task creation, inter-task communication and synchronization, and real-time constraints. The main problem is to close the gap from concurrent, communicating task specification to the actual (usually single-threaded) target processor implementation, without making a compromise on the required real-time performance and with actively considering cost effectiveness (especially energy consumption). A systematic approach towards (software) system design aiming at reducing the design-time and the number of errors and the debugging effort of embedded systems/software, consisting more and more of distributed (software) behaviour running and communicating across multiple processors, is mandatory.
[0098] 6.1.2 Target Application Domain
[0099] The target application domain of the task-level system synthesis approach advocated by us is advanced real-time multi-media and information processing (RMP) systems, such as consumer multi-media electronics and personal communication systems. These applications belong to the class of real-time embedded systems involving a combination of complex data- and control-flow where complex data types are manipulated and transferred. Most of these applications are compact and portable devices, putting stringent constraints on the degree of integration (i.e. chip area) and on their power consumption. Secondly, these systems are extremely heterogeneous in nature and combine high performance data processing (e.g. data processing on transmission data input) as well as slow rate control processing (e.g. system control functions), synchronous as well as asynchronous parts, analog versus digital, and so on. Thirdly, time-to-market has become a critical factor in the design phase. Fourthly, these systems are subjected to stringent real-time constraints (both hard and soft deadlines are present), complicating their implementation considerably.
[0100] Another major driver for this type of research are applications like the new MPEG4 standard (see FIG. 7. 12 ), which involves a massive amount of specification code (more than 100K lines of high-level C++ code) and which combines video, synthetic images, audio and speech modules with a system protocol. The IM1 application on which we are focussing is based on the MPEG4 standard, which specifies a system for the communication of interactive audio-visual scenes composed of objects.
[0101] 6.1.3 Task Concurrency Management at the Grey-Box Level
[0102] We propose to look at a new abstraction level of mapping such real-time embedded systems, with emphasis on performance and timing aspects (concurrency management and meeting of the timing constraints or ‘timeliess’) while minimizing (abstract) processor cost overhead. Our focus lies especially on the task-level abstraction. But in contrast to existing approaches we will work neither at the detailed “white box” task model where all the operations are considered already during the mapping and where too much information is present to allow a thorough exploration, nor at the “black box” task model, where insufficient information is available to accurately steer even the most crucial cost trade-offs. Indeed, in the latter case the tasks are precharacterized by an initial design stage. But during the mapping, these costs and constraint parameters are not updated, which is crucial to obtain a good mapping involving transformations on the internal and I/O behaviour of the tasks.
[0103] At our targeted abstraction level the distinction between “hardware synthesis” and “software mapping/synthesis” is practically gone so that all steps in the proposed design trajectory can then be shared for both target types of platforms. That enables a much more global design space exploration than in the traditional way. One of the major consequences is that the system cost can be significantly reduced and tighter timing/performance constraints can be met. In addition, the automation support can be mostly unified, which heavily limits the man-power investment required in research, development and production at this stage.
[0104] The main problems are:
[0105] 1. Very complex (software type) specs. So the traditional solutions (white box view approach) fail. Instead we propose to use a grey-box modeling approach where only the essential data types, control/data-flow and dynamic constructs like semaphores and external events are present (see FIG. 7. 6 ). A real-life example is presented in 7 . 7 On this initial grey-box model, we have to apply task-level transformations to further reduce the complexity and to expose more concurrency.
[0106] 2. These systems are extremely dynamic due to the inherent user interactivity, the scalability and the presence of agents/applets. So conventional DSP models (derived in the past mostly from the “physical/link” layer of terminals) are not feasible any longer, and these have to be substituted by support of the global dynamic control flow at the grey box level. Instead, we need a model like the multi-tread graph (MTG).
[0107] 3. Many complex data co-exist where manipulation is more important than the applied operations. Hence a strong focus on storage and transfer is needed. Solutions from the operation-level can be largely reused here for the data transfer and storage exploration stage. However, in addition, aggressive static data type refinement and (due to the dynamic nature) dynamic memory management have to be supported. At the end the address and condition/loop overhead introduced by the code transformations of these stages has to be removed again too.
[0108] 4. Complex timing and concurrency constraints are present. As a result, in current design practice, nobody can really manage a thorough “exploration” at this stage either because of a too low abstraction level (white box level with too many details) or of not enough info (UML and black box models). In contrast, our grey-box abstraction provides the right level to efficiently explore this, i.e. focussing on the dynamic constructs (events, semphares, threads) and the timing issues, together with the main data types and their control-data flow dependencies.
[0109] 5. Cost-efficiency is still required for embedded systems, so power, required band-width, memory size are all very crucial to incorporate during the system design. Hence, we need a global exploration, driven by analysis feedback as opposed to the (nearly) blind mapping which designers are stuck with today (because only the last phase of the system design trajectory is supported by compiler tools). For this analysis fully automated and fast exploration tools with appropriate internal models are required, because interaction with designer is hopeless due to bookkeeping and global information processing during this “search space exploration”.
[0110] 6.1.4 Embedded Systems—Task-Level Design Problems
[0111] We aim at providing design support for the development of real-time embedded systems, with special focus at the task-level, so the understanding of the development process is essential.
[0112] The cost-effective implementation of real-time embedded systems should span two levels of abstraction (see also FIG. 7. 8 ). At the more traditional ‘operation/instruction level’, the design consists of the actual coding of the different concurrent sub-behaviours in the system, often called ‘tasks’, on the (programmable) instruction-set or custom processor. At a higher level, which we call ‘task level’, a concurrency management stage must be performed. This stage takes care that the different tasks coordinate (i.e. communicate, synchronize, coordination of resources, . . . ) on the same processor or on a set of processors, within the real-time constraints.
[0113] At each concurrency level, decisions relevant to that specific abstraction-level are introduced. These decisions are propagated as top-down ‘constraints’ to the subsequent levels. This gradually restricts the design search space and supports ‘gradual refinement’ of the design across different abstraction levels, leading to a global optimal result. To cut the dependency on lower level design decisions—i.e. a bottom-up dependency—of a higher level stage, ‘estimators’ must be resided to which give an approximation for the lower level design decision impact. Similarly, bottom-up information regarding pre-taken architectural (or other) design decisions (e.g. selection upfront the target programmable processor) needs to be propagated from the lower to higher level stages.
[0114] The data concurrency level—which can be exploited by allocating ‘array-processors in the architecture—will not be discussed further here.
[0115] At each concurrency level, both the data transfer and storage issues and the concurrency issues are addressed. The former are performed in the ‘Data Transfer and Storage Exploration’ (DTSE) stages (see FIG. 7. 8 ). These DTSE stages are all focused on the manipulation of the complex data types (like arrays).
[0116] Operation/Instruction Level
[0117] This belongs to the prior-art and hence it will not be discussed here any further.
[0118] Task Level
[0119] The challenge of tomorrow is to map a complete system-level behavioural description, merely consisting of a number of interacting processes rather than a single algorithm to these valuable components.
[0120] The main problem is to close the gap between these two abstraction levels (i.e. system-level versus operation/instruction-level) by automating the ‘system/software embedding’ step; by this step, we mean the actions taking care that the set of processes can run on the same target by coordinating their interaction with each other and with the environment, and that the component is embedded in the rest of the system.
[0121] A major feature of our proposed approach is that additional abstraction levels and design stages (labeled ‘validation-refinement-optimization’) are introduced. These have to be tackled before the traditional SW/HW partitioning is performed, as indicated in FIG. 7. 8 .
[0122] The main sub-problems which we discern and that should be solved at the task-level are:
[0123] 1. task concurrency extraction: the system specification may contain implicit task-level concurrency, requiring a separate pre-processing step which analyzes and extracts the amount of concurrency. In several cases, (control) transformations provide considerable improvements on the available concurrency, the freedom in scheduling and the reduction of the critical paths.
[0124] 2. real-time system model: powerful and portable programming models supporting real-time are needed which isolate the (task-level) specification from the underlying processor hardware (either programmable or custom) and in this way enhance portability and modularity and stimulate re use.
[0125] 3. automatic time-driven task scheduling and scheduling algorithm selection: as indicated above, the scheduling in the presence of various constraints is too difficult to perform manually. Moreover, there is a clear need for algorithms which consider the concept of time directly (i.e. ‘time-driven’). The automated selection of the scheduling algorithm is needed since the requirements of different applications widely vary. A massive amount of work on scheduling has been performed and in this in a variety of communities but few approaches are available on ‘selection’.
[0126] 4. processor allocation and assignment: as multi-processor targets are key elements in future systems, the partitioning of the specification over the different processors is too complex to be left to the designer, due to the complex and interacting cost functions, like schedulability, communication and memory overhead.
[0127] 5. resource estimators: in order to generate an optimal mapping and scheduling of the specification onto the available processors and in order to generate the schedule as well as to verify its feasibility, data on the use of CPU resource (i.e. cycles) and memory is required. Furthermore, the number of processors, buffer lengths, . . . are key to both scheduling and partitioning sub-tasks. Estimations can be generated using profiling, simulation, source code analysis and generated code inspection (e.g. linker map tables).
[0128] 6. high-level timing estimators: at a high-level in the design script, timing estimators are needed to guide the design decisions (e.g. processor allocation), ensuring timeliness of their outcome. It is merely estimators for the execution times of behaviour capable of dealing with partially implemented behaviour which are lacking rather than the timing analysis. Existing timing analysis approaches can be re-used by feeding in the execution time estimations provided by these tools. These estimators must be capable of dealing with, amongst others, incompletely refined communication (e.g. no insertion of data type conversion, protocol conversion, and even without bus assignment), absence of memory (hierarchy) decisions (e.g. levels of caching, number of memories and their number of ports, memory organization) and absence of partitioning and allocation decisions.
[0129] 7. interface refinement: comprises of the following: (1) synchronization refinement, (2) data type conversion, and (3) scalar buffering. The first refines the high-level communication present in the input specification into a concrete IO-scenario taking into account processor characteristics (like peripherals), the throughput requirements and the size of inserted buffers. Software device drivers have to be synthesized and dedicated logic must be inserted to interface the (programmable or custom) processors to each other or to dedicated peripherals. The second ensures data type compatibility on the different communication sides by inserting behavioural conversions.
[0130] 6.1.5 Pareto Curves and Their Use at the Task Level
[0131] Due to the task-level exploration with the steps proposed above, it is possible to derive Pareto curves which indicate the points in the search space where a (set of) cost(s) is optimal relative to a constraint like the time budget. Non-optimal points in the search space that are “dominated” by other points should not be considered for subsequent implementation. That information is crucial for the system designer to decide on trade-offs with other subsystems present in the entire application. If the cost is energy, and when we map the initial MTG/CDFG specification on a pair of two processors, one with high Vdd and one with low Vdd, we can trade-off time and energy by moving more tasks from the low Vdd to the high Vdd one. The execution time indeed goes up roughly linearly with Vdd while the energy decreases quadratically. The optimal trade-off points typically lead to a curve as indicated in FIG. 7. 9 . That curve should include both the data transfer and storage (DTS) related cost and the processor core related cost. In practically all current exploration approaches that DTS cost is ignored or considered as constant. However, when the time budget is decreased, both these costs typically go up. The DTS cost increases because usually more system pipelining (buffering) has to be introduced and also the mapping on the SDRAM organisation and the processor caches becomes more costly under stringent time budget constraints. The processor cost increases because more subtasks have to be moved from the low Vdd to the high Vdd processor during assignment and scheduling, in order to meet the more stringent timing requirements.
[0132] Due to the aggressive application of task-level concurrency extraction and concurrency improving transformations, the additional concurrency and reduced complexity can be exploited to move the location of the Pareto curve left and down for the processor core contribution (see FIG. 7. 10 ). This indeed allows to better exploit the low Vdd processor during the task-level assignment and scheduling. Consequently the (energy) cost goes down. The DTS cost can be improved also because DTSE related code transformations allow to remove redundant accesses, and to improve the regularity, locality and data reuse behaviour. In addition, the concurrency improving transformations provide more access ordering freedom to remove part of the internal overhead (size especially) for the dynamically sized buffers. The transformations can however also be used to speed tip the implementation, i.e. to break up the critical path and hence enable tighter time budgets to be achieved (at a potentially higher cost of course). As a result, the global Pareto curve after the transformations represents significantly improved solutions in the search space, both in terms of the cost required for a given time budget and in terms of the minimal time budget that can be reached.
[0133] When these Pareto curves are precomputed for several task clusters at design time for a given embedded application running on a given processor configuration, they can then be used also to improve the global behaviour of the system in a very dynamic environment. Indeed, the steering of the scheduling and processor assignment of these task clusters on a set of processor and storage resources (a “platform”) can then be dynamically improved in the presence of “foreign” tasks that are entered on the platform as agents or applets (see New Task3 in FIG. 7. 11 ). The cost-time behaviour (the Pareto curve) of these entering tasks will then typically not be known, but their required time budget is almost always derivable (or estimatable). The required extra time on the resources then has to be subtracted from the currently running task clusters (Task1 and Task 2 in FIG. 7. 11 ) and this involves an optimisation problem because depending on how much each of them is squeezed, the cost effect will be lower for one/some of them compared to the others. For instance, in the example of FIG. 7. 11 it is clear that when the initial time budgets of Task1 and Task2 are to the right side of TB1, it is best to squeeze Task2. As soon as that point is reached, it is better to start squeezing Task1 until it cannot be speeded up further. Such trade-offs to be taken can be effectively taken into account at run-time (by a customized part of the embedded operating system) by analyzing their precomputed Pareto curves. This will allow to significantly decrease the energy or size costs while still meeting all the timing constraints, because each of the task clusters can operate close to one of its optimal points in the overall search space.
[0134] 6.2 Extraction of the Grey-Box Model
[0135] The C++ code is considered as a description of tasks performing specific logical operations. These tasks consist in their turn of threads that run continuously and independently from each other. The threads are a CDF description of functions triggered by an event signal. The primitive semantic that forms the thread is a thread node. This three-layer approach is described further in detail. In the lower level, the CDF parts of the functions are split in “seen” and “bidden” sublayers. The lowest (hidden) sublayer is a group of thread nodes consisting of CDF with purely primitive operations. In the highest (seen) sublayer, these thread nodes are grouped in threads that also include CDF with the thread nodes as primitive. The distinction between a thread and a thread node is the dynamic, non-deterministic behavior of the former in comparison to the primitive operations performed by the latter. In the middle level the “seen” and “hidden” approach is again applied. The dynamic threads are connected with MTG semantics and grouped in higher-level tasks. The criterion for this grouping is the logical functionality of the system and therefore could change after the transformation step. Since the main functionality remains the same and the general steps are called again and again in the process, a global view of the system can be generated. In that sense a grey-box model can be extracted both for the MTG (middle) and the CDF (lower) layers. The steps to be performed to get from the initial system specification (C/C++ code or high level information) to the grey-box model to be used as input for TCM exploration are the following:
[0136] Extraction of the black-box model based on the high-level system specification, which is in most cases available. The global view of the system's functionality is represented in black boxes with no information about their content, the algorithms used, the operations performed on the data types or the detailed dependencies between them. It is only a very abstract representation of the system to give the general picture of the function boundaries that must be retained during the changes later in the exploration process.
[0137] Looking inside the black-boxes, the operations of the main functionality are drawn with the function scope of the C/C++ code. The functions are considered as thread nodes for the moment and the black-box approach is extended with control and data flow edges to connect these thread nodes.
[0138] Operations like variable assignment or primitive functions are grouped together in a thread node because they are considered as an implementation of an abstract CDFG functionality.
[0139] Conditional guards of branches that are not local in a function but depend on a completely different functionality indicate an ordering or a dependency between the two threads. From this point on, the top-down approach is taken, so we work on the details of the functions but always keeping the global picture of the system. The “for” and “while” loops are detected and represented inside the function scope. They are considered as important if the number of iterations is data dependent or if the loop body times the number of loop iterations is large and hence represents a high execution time on the final target processor.
[0140] Non-deterministic behavior that has to do with synchronization is taken into account. Semaphore reserve and release indicate the boundary of a group of functionalities interacting with another one as far as data interchange is concerned. Other non-deterministic issues like the creation of threads or/and tasks are also annotated on the diagrams inside the function scope.
[0141] 6.3 Task-Level Transformations
[0142] In this section we will present first the real-life results of task-level transformations. Afterwards, we will give an overview of the different types of transformations that we distinguish.
[0143] 6.3.1 Real-Life Examples of Transformations That Improve the Amount of Concurrency
[0144] Description of the Transformations
[0145] When developing an initial model of a system, specification engineers normally spend neither time nor energy to expose all possible concurrent behavior. They are mainly concerned with the functionality and the correctness of the system. As a result, the software model that they create hides almost all concurrency. However, for the design engineers it becomes an almost unmanageable and very time consuming problem to extract the concurrency from this initial specification and to map it on a concurrent architecture within stringent time constraints. Therefore, they will either redesign the system from scratch or use a faster and thus more power consuming architecture. In our design flow, on the contrary, we model the initial specification on a grey-box level that allows us to systematically identify and transform the time critical parts. We start to analyze the data dependencies that inhibit concurrency. When no recursion is involved, the scope of these data dependencies can be reduced by adding extra buffering (and possibly a small additional routine to synchronize the data). However, the main difficulty is to detect these data dependencies. Software designers often prefer to use run-time constructs to model data dependencies between the boundaries of tasks as this gives them more flexibility to change their initial specification afterwards. Hence, they conceal data dependencies with semaphores or mutexes, seemingly required for a non-deterministic behavior. Therefore, we carefully analyze all these constructs in our grey-box model to determine the really needed ones. This is an enabling step that to allow us to then actually break dependencies by introducing a small buffer. We will illustrate this approach with two real examples extracted from the IM1 player. To make the examples comprehensible, we will give here a short introduction of the parts that we have invested
[0146] The IM1 player is based on the MPEG4 standard, which specifies a system for the communication of interactive audio-visual scenes composed of objects. The player can be partioned in four layers (see FIG. 7. 12 ): the delivery layer, the synchronization layer, the compression layer and the composition layer. The delivery layer is generic mechanism that conveys streaming data to the player. Input streams flow through the different layers and are gradually interpreted. We mainly focus on the compression layer. This layer contains several decoders. Two important ones are the BIFS and the OD decoder. The BIFS decoder interprets the data packets that describe the composition of the scene objects. The output of this decoder is a graph. Each node in this graph presents either an object in the scene or describes the relation between the different objects. However, to represent some of the scene objects extra AV-data is needed. How this data needs to be conveyed to the compression layer and how it needs to be decoded is described in Object Descriptors (OD). These ODs are encoded in one or more streams entering the compression layer and are decoded by the OD decoder. The ODs are linked with the nodes requiring the extra AV-data. In the first example, we have changed the relation between the synchronization and compression layer. Originally, the two tasks were separated with a buffer protected against simultaneous access with a mutex, i.e. WaitForData mutex presented in FIG. 7. 13 left. This figure is a part of the grey-box model that we have used for our analysis. As a result of this semaphore, both tasks were always executed sequentially. However, this semaphore was only needed to model a data dependency: the compression layer cannot start to decode before data is available at the output of the synchronization layer. Therefore, we have replaced the semaphore with a data dependency, indicated in the figure with the bold dashed dotted line. Moreover, no recursion was involved with this data dependency. Hence, by increasing the size of the (small) buffer, the synchronization layer is allowed to handle a next data packet, while the compression layer is decoding the previous one. At the cost of some extra buffering, we have succeeded in increasing the amount of concurrency.
[0147] A second example illustrates a similar principle. In the compression layer of the player, the OD and BIFS decoder share a data structure, i.e. the graph representing the scene. Above we have described that this graph is the output of the BIFS decoder. The OD decoder also accesses this graph to link ODs with the nodes in the graph. The graph is protected against simultaneous access by the BIFS and OD decoder with a semaphore. As a result, they cannot run in parallel. After a more thorough investigation, we have found out that the links between the ODs and the nodes in the graph are not needed during the execution of either the BIFS or the OD decoder. Therefore, we have broken the data dependency by postponing its initialization until after the execution of both decoders. Hence, the OD decoder does not need to access the graph and can work independently of the BIFS decoder (see FIG. 7. 13 right). This again costs some extra buffering plus a small extra initialization routine.
[0148] As a side-effect of this transformation, extra concurrency inside the OD decoder becomes available. The ODs were previously decoded sequentially because of the access to the shared graph. By removing this dependency, they can now be executed in parallel. Using this concurrency we create extra freedom for the task scheduling.
[0149] We believe that such transformations can be generalized for similar graphs with other contents of task behavior. In the next section we will show how these transformations affect the overall cost-performance trade-off of the system even on a weakly parallel platform.
[0150] Results of the Transformations: Task Scheduling Experiment on a Weakly Parallel Platform
[0151] Two parallel ARM7TDMI processors, running at 1V and 3.3V respectively, are used to illustrate the scheduling. The main constraint for scheduling is the time-budget. For one task, we use t L and t H to denote the its execution time on the 1V ARM7TDMI and 3.3V ARM7TDMI respectively and Δt to denote the difference between these two execution times. Similarly, we use E L and E H to denote its energy cost of the processor to run on 1V ARM7TDMI and 3.3 ARM7TDMI and AE to denote the energy difference. Our calculations are based on the following formulae.
Δ t = t L - t H = ( 1 - 1 3.3 ) t L ( 6.1 ) Δ E = E H - E L = ( 3.3 2 - 1 ) E L ( 6.2 )
[0152] For the first experiment the time-budget starts at the reading of one VOP 1 data and expires at the end of the decoding of the data (see FIG. 7. 12 ). The original implementation dictates that the data can only be read and decoded sequentially. Due to this limitation, we can only reduce the period by executing some tasks on a high Vdd processor.
[0153] The second experiment gives similar results. Given is a group of media objects, i.e. a group of nodes. The time-budget starts now at the beginning of parsing the first node and expires at the end of the setting up the decoder for the last node. Each of these nodes will undergo three steps: first its description is parsed by the BIFS decoder, the related OD is then parsed by the OD decoder and finally the AV decoder described in the OD is set up by the OD decoder. Originally the BIFS and the OD decoder run sequentially. That is, OD decoding only starts after all the nodes finishes their BIFS decoding. The time-budget and total energy cost of the original Pareto-optimal points in the search space are shown with asterix points for both the first and second experiment on the left and right side of FIG. 7. 34 respectively.
[0154] After the TCM related transformations discussed above that lead to the transformed task graph, we can remove these implicit sequential restrictions in the code. Consequently, we can better utilize the two processors by exploiting the concurrency. Hence, we can achieve the same time-budget with less energy cost or we can reduce the minimally achievable time-budget due to the added flexibility. The scheduling results for the transformed graphs are also shown in FIG. 7. 34 , with the diamond points. Gains of 20% and more are achievable in energy cost and the maximal speed can be increased with nearly a factor 2.
[0155] 6.3.2 Overview of Different Transformations
[0156] Simplify the Grey-Box Model
[0157] Hierarchical rewriting
[0158] In the concept of focusing in the TCM related parts, the code that is not providing any freedom to the transformation and scheduling steps is hidden. This is done in two layers of hierarchy according to the following criteria:
[0159] The critical-path: the control flow and data flow of the data types that are relevant to the system main functionality.
[0160] The most important data types of the system and the dependencies on them like loops whose number of iterations is data dependent.
[0161] The existence of dynamic events that include the semaphores and the mutex, the dynamic creation of tasks and the event signals between the environment and the system.
[0162] The timing information: this includes the average execution time of the functions and the execution time of a loop. The loops are important because of the fact that even if the loop body is not time consuming, the number of iterations may be large enough to make the total execution time of the loop “interesting”. In the case where the white box specification is not available, the time information is being derived by the partial system specification or by estimates based on logical assumptions that are being verified later in the design process. Examples illustrating the transformation are in FIG. 7. 15 and FIG. 7. 16 .
[0163] In the lower layer the CDF parts of the functions are “seen” or “hidden”. The outcome at this level is thread nodes consisting of CDF of purely primitive operations. In the middle layer these thread nodes are grouped in threads that also include CDF with the thread nodes as primitive. In this layer the “seen” and “hidden” approach is again applied. Since the main functionality remains the same and the general steps are called again and again in the process, a global view of the system can be generated. In that sense a grey box model can be extracted. In each exploration step, we focus first locally in some parts that include the basic bottlenecks (see criteria below) and “hide” the rest threads in black boxes. The semantics of the MTG model are expanded for this two-layer distinction. For the “hide” parts in both layers a table of correspondence is used. The parts of a function body that are not relevant to the CDF and to the main functionality of the system are grouped and given a general name indicating the “functionality” that is performed. A function bubble is used for their representation in the TCG. The other parts of the function body that are important according to the criteria are kept in the “seen” part. In this way there is less details in the diagrams, a more global view of the functionality of the system and the complicated but unnecessary information is pruned away. On the other hand if later in the process we find that it is needed to split the “bubble” (because it takes considerable amount of time or because we need to take a closer look at the CDF) we still have the “lighter-grey” box model by using a table.
[0164] Hide undesired constructs
[0165] In this step we “hide” the parts of the graphs that introduce complexity without adding any new TCM related concepts. This “hiding” is done without trade-off because at this pre-processing level the transformation should just simplify the initial TCG. In that context, the transformations should not affect the CDF of the system. The functionality remains the same but parts that are not related to the TCM focus are pruned to the “hidden” 3rd layer of DTSE. Example: the ODDecoder is creating a FileReader thread if mActive is not set in the RequestChannels and the m_state is required. Illustrated in FIG. 7. 17 .
[0166] Create Freedom
[0167] Code expansion
[0168] Example: a subroutine that is called by different threads and a part of it is “hidden” but the “seen” part is instantiated in the different calls to allow more freedom for the scheduling later on. There is however a more complex case where the “seen” part changes according to the context of the thread from which it is called. This can be achieved by passing different argument values or by setting different variable values. In this case, the “seen” part consists of two different instances according to the context. Each instance will be used in the corresponding thread. Examples illustrated in FIG. 7. 18 , FIG. 7. 19 and in FIG. 7. 20 .
[0169] It should be stressed here, that this kind of transformations do not affect the functionality of the system but only give more freedom to scheduling by reducing the complexity in the diagrams.
[0170] Remove constructs that prohibit concurrency analysis
[0171] DTSE objective: The general concept is to propone the reading and postpone the writing.
[0172] TCM objective: the basic goal is to introduce as much concurrency as possible. In this context the parts of the system that are independent but executed sequentially because of the nature of C++, are being decoupled by the control flow and considered to be executed in parallel.
[0173] Example follows in FIG. 7. 21 :
[0174] Transform constructs that prohibit concurrency analysis
[0175] Trade-off: If the transformed graph is not equivalent to the initial one, the new degree of complexity and concurrency in compare to freedom should be taken into account. The control edges that impose strict constraints to TCM are moved or an assumption is introduced to create more freedom. An example of this transformation is given in section 6.3.1. Example follows in FIG. 7. 22 and in FIG. 7. 23
[0176] No trade-off: At this step only the transformations that result in the same functionality are performed. The functions are split into these thread nodes that are common between them and then merged into one. Example follows in FIG. 7. 24 .
[0177] Concurrency Analysis
[0178] The system is analyzed globally in order to detect the parts that can run independently and thus concurrently. This step focuses on the potential parallelism and lists the bottlenecks that inhibit it. This is illustrated in FIG. 7. 25 .
[0179] Reduce Complexity Exposed by More Detailed Concurrency Analysis
[0180] Remove unused code
[0181] This step aims at keeping only the main operations of the system functionality and to remove the redundant code as far as the asserting (extra) checks and the variable-set are concerned. This is similar to step 2 for creating freedom but in this phase, the parts removed are those that were not obvious in the plane C++ code. Because of the concurrency analysis information (including data flow arrows) the redundant information is already abstracted away, the system functionality is handled more globally, allowing for extra redundant dependency/constraint/code detection. E.g. when the value of an argument (important data), which is passed from one function or instance of a class to another, is known in advance, only the body of the branch that is triggered depending on this value is left in the diagrams. Example follows in FIG. 7. 26
[0182] Reduce complexity by trading off globality of exploration and hence result quality Example follows in FIG. 7. 27 :
[0183] Weight-based hiding of less crucial constructs
[0184] Hide the code that is still complex or even impossible to handle (i.e. non-determinism) and is less relevant in comparison to the other parts that are retained. The hiding is done by putting a threshold (complexity target based) on the list of retained code constructs, which are first ranked based on the relative importance of still difficult to handle issues.
[0185] Partitioning
[0186] At this phase the threads are grouped in task clusters that form the dark-grey-box model of the system. This is the third and higher level of hierarchy (see above). In the highest layer of the grey-box model, tasks are grouped into task clusters where the main characteristic is that low communication and interaction are present between the combined tasks. So, one objective is to decouple them in the highest possible degree e.g. for later task scheduling Typically also the dynamic move of sets of tasks over a network (e.g. as Java applets) is captured through the concept of a task cluster that is dynamically created at other nodes. Example follows in FIG. 7. 28 :
[0187] 6.4 Scheduling at the Task-Level
[0188] The first section presents how we organize scheduling at our abstraction level. Moreover, it illustrates the benefit that can be obtained using both our static and dynamic scheduling techniques on real-life example. The second section gives another illustration of the results that can be obtained with our static scheduling techniques.
[0189] 6.4.1 Scheduling at the Task-Level
[0190] The design of concurrent real-time embedded systems, and embedded software in particular, is a difficult problem, which is hard to perform manually due to the complex consumer-producer relations, the presence of various timing constraints, the non-determinism in the specification and the sometimes tight interaction with the underlying hardware. Here we present a new cost-oriented approach to the problem of task scheduling on a set of processors. It fits in a global task concurrency management approach developed at IMEC. The approach uses as much as possible pre-ordering of the concurrent behavior under real-time constraints and minimizes the run-time overhead. At the same time, the scheduler will try to minimize cost such as the energy consumption. The approach is shown for two processors but it is easy to expand this method to include more than two PEs.
[0191] Overview
[0192] An embedded system can be specified at a grey-box abstraction level in a combined MTG-CDFG model. This specification is functional in representing the idea of concurrency, time constraints and interaction at either an abstract or a more detailed level, depending on what is required to perform good exploration decisions afterwards. According to the IMEC TCM approach, the task concurrency management can be implemented in three steps. Firstly the concurrency extraction is performed. Task transformations on the specified MTG-CDFG will be applied to increase the opportunities for concurrency exploration and cost minimization. After the extraction, we will get a set of thread frames (TF), each of which consists of many thread nodes and which can be looked at as a more or less independent part of the whole task. Then static scheduling will be applied inside each TF at compile time, including a processor assignment decision in the case of multiple PEs. Finally, a dynamical scheduler will schedule these TFs at run time on the given platform.
[0193] The purpose of task concurrency management is to determine a cost-optimal constraint-driven scheduling, allocation and assignment of various tasks to one or more processors. In this report we consider a system consisting of two different processors, on which a thread node can be executed at different speed with different cost, here energy consumption. Given a thread frame (TF), static scheduling is done at compile time to explore the possible points on the global Pareto curve, where each point means a different choice in cycle budget and energy consumption trade-off. The idea here is that each thread node in the TF can be allocated to either of the two processors at different relative order if such an assignment can satisfy all the time constraints internal or external to that TF. By doing this, the cycle budget and energy consumption for the whole thread frame will also change accordingly. Each of these points is a different choice of all the possible allocation and scheduling options for this TF and the lowest edge of all these points is just the Pareto curve. Since the static scheduling is done at compile time, computation efforts can be paid as much as needed, provided that it can give a better scheduling result and reduce the computation efforts of dynamic scheduling.
[0194] At run time, the dynamic scheduler will then work at the granularity of thread frames. Whenever new thread frames come, the dynamic scheduler will try to schedule them to satisfy their time constraints and minimize the system energy consumption as well. The details inside a thread frame, like the execution time or data dependency of each thread node, can remain invisible to the dynamic scheduler and reduces its complexity significantly. Only some useful features of the Pareto curve will be passed to the dynamic scheduler by the static scheduling results, and be used to find a reasonable cycle budget distribution for all the running thread frames.
[0195] We separate the task concurrency management into two separate phases, namely static and dynamic scheduling, for three reasons. First, it can better optimize the embedded software design. Second, it lends more run time flexibility to the whole system. Third, it minizes the run time computation complexity. The static scheduler works at the grey-box level but still sees quite a lot of information from the global specificatin. The end result hides all the unnecessary details and the dynamic scheduler only operates on the granularity of thread frame, not single thread node.
[0196] Static Scheduling
[0197] The behavior of a thread frame can be described by task graphs like FIG. 7. 29 , where each node represents what functions to perform and their performance requirements. Each edge represents the data dependency between these nodes. The task graph we use here can be seen as a simplified subset of the MTG model and each function is a thread node in MTG. This example is part of a real voice coder. Tab. 7.1 gives the performance of each node on our two processors. Here some assumptions similar to those in the later ADSL example are made. Though it is not showed here, we can add some other time constraints to the task graph, for instance, task t 4 must start n time units after task to ends. The TF is scheduled in a non-preemptive way here because we have the a priori knowledge of all the nodes involved.
[0198] We use a MILP algorithm to solve the static scheduling problem. Other algorithms can be used here as well. Before giving the algorithm, we need some variable definitions.
[0199] Definition 6.4.1 All Variables Used for Static Scheduling.
L , H two processors δ i , L = { 1 task i is allocated to processor L , 0 otherwise δ i , H = { 1 task i is allocated to processor H , 0 otherwise C i , L the execution time of task i on processor L C i , H the execution time of task i on processor H E i , L the energy consumption of task i on processor L E i , H the energy consumption of task i on processor H T i S the start time of task i T i E the end time of task i b i1 , i2 = { 1 task i1 ends before task i2 starts 0 otherwise
[0200] Our aim is to minimize the energy consumption of the whole thread frame, so the object function can be easily defined,
Minimize : ∑ i E i , H δ i , H + E i , L δ i , L . ( 6.3 )
[0201] The following constraints have to be fulfilled.
[0202] 1. Mapping Constraints. Each thread node t i is executed on only one processor, which is represented in Eq. 6.6.
δ i,L ≦1 (6.4)
δ i,H ≦1 (6.5)
δ i,L +δ i,H =1 (6.6)
[0203] 2. Timing Constraints. The task end time is the addition of task start time and execution time.
T i E =T i S +C i,L δ i,L +C i,H δ i,H (6.7)
[0204] 3. Precedence Constraints. If thread node t i is the immediate predecessor of thread node t j , then
T i E ≦T j S (6.8)
[0205] 4. Processor Sharing Constraints. For any two thread nodes t i and t j , that are allocated to the same processor, if t i is a predecessor or successor of t j , it can never happen that one node will start before the other one ends due to the precedence constraints. Otherwise, the binary variable b i,j is used to describe the processor sharing situation.
T i E ≦T j S +(3− b i,j −δ i,L −δ j,L )* C 1 (6.9)
T j E ≦T i S +(2+ b i,j −δ i,L −δ j,L )* C 2 (6.10)
T i E ≦T j S +(3− b i,j −δ i,H −δ j,H )* C 1 (6.11)
T j E ≦T i S +(2+ b i,j −δ i,H −δ j,H )* C 2 (6.12) (6.13)
[0206] In the above equations, Eq. 6.9 and Eq. 6.10 are sharing constraints on processor L. When thread node i and j are both allocated to processor L, i.e., δ i,L =δ j,L =1, if b i,j equals one, i.e., task i ends before task j starts, Eq. 6.9 gives the exactly same hard constraint T i E ≦T j S and Eq. 6.10 becomes T j E ≦T i S +C 2 , which can be ignored if C 2 is large enough; if b i,j equals zero, Eq. 6.10 gives the hard constraint T j E ≦T i S and Eq. 6.9 can be ignored. Eq. 6.11 and Eq. 6.12 describe the similar sharing constraints on processor H. When node i and j are allocated to different processors, all of the above equations will be ignored. Constants C 1 and C 2 should be large numbers to ensure that the ignored equation will bring no effect.
[0207] At the end, a deadline for the whole thread frame can be given, which introduces a global constraints to all the nodes,
T i E ≦Deadline.
[0208] Now our problem becomes a deadline constrainted energy minimization problem. To every given thread frame deadline, the above MILP equations will give an energy optimized solution. In fact, time constraints other than the whole thread frame deadline can be added easily. For instance, there can be a separate deadline for each node.
[0209] We have done the static scheduling for the thread frame shown in FIG. 7. 29 with the performance given in Tab. 7.1. When the deadline of the whole thread frame is 100 time units, the result given by the MILP solver is shown in FIG. 7. 30 .
[0210] Changing the deadline for the whole thread frame, we can obtain a series of points. Each of these points is the optimized energy cost at the fixed deadline and they make up the well known Pareto curve in FIG. 7. 9 .
[0211] From these points, several ones will be chosen by the static scheduler as typical cases(those indicated by triangles) and will be passed to the dynamic scheduler. The more points are passed, the better a result the dynamic scheduler can achieve, but at a higher run time computation complexity.
[0212] Dynamic Scheduling.
[0213] Static scheduling provides a series of possible options of allocation and scheduling inside one thread frame, but actually which option would be chosen is decided only by the dynamic scheduler at run time. The dynamic scheduler takes into consideration all the computation requests from all the ready to run thread frames and tries to find a choice for each thread frame so that the whole combinational energy consumption is optimal. At this stage, the clustered entities, namely thread frames, have already been distributed and assigned across the allocated processors. The dynamic scheduler operates on the base of thread frames and tries to satisfy the inter-task timing constraints.
[0214] Take the two thread frames in Tab. 7.2 as instance. Each of these two thread frames has three options corresponding to different cycle budget and energy cost combination. These options are identified by the static scheduler. At run time, if the total cycle budget for these two thread frames is 100, the energy optimal scheduling is option 1 for thread frame 1 and option 3 for thread frame 2. However, the optimal scheduling will become option 2 for thread frame 1 and option 3 for thread frame 2 when the cycle budget is 140. Both cases are depicted in FIG. 7. 31 .
[0215] Inter-task time constraints, such as the data dependency or execution order among the thread frames, can also be taken into account at this step.
[0216] Experiment on ADSL.
[0217] In the last section, we have only illustrated the general method we proposed in the task concurrency management context. To better assess the viability of our approach, we have applied it to a more complex ADSL (Asynchronous Digital Subscriber Line) modem application.
[0218] ADSL System Architecture.
[0219] [0219]FIG. 7. 33 shows the system architecture of the ADSL modem.
[0220] This design consists of both hardware components and an important part of embedded software which exhibits real-time constraints. The digital hardware part includes two parallel datapaths for the receiver and transmitter respectively. The receiver datapath consists of a front-end, a FFT transformer, a QAM demapper, an error and noise monitor and an error-correction decoder. The transmitter datapath has a similar structure. Both datapaths have their own hardware timing controller (DSTU=DMT Symbol Timing Unit). These DSTUs will activate the processors at the correct moments to do the appropriate processing of the DMT (Discrete Multitone) symbols.
[0221] Next to the hardware components, an ARM core processor runs the software that is responsible for programming and configuring the hardware. It has a control part, that configures the hardware to execute the different stages of the initialization sequence, and an algorithmic part to execute DSP functionality not implemented in hardware. The control part of the embedded software can be described as a reactive system, reacting on events generated by the monitor and other hardware modules, taking into account real-time constraints imposed by the ADSL standard.
[0222] In our example, we try to schedule the system consists of the two DSTU and SW modules (the modules in shadow) and model it into two threads. The two DSTU controller make up a thread frame which is generated periodically every 230 μs and the deadline equals the period. The SW module generates another thread frame dynamically when the corresponding event has been triggered. The deadline for the SW thread frame is derived from the ADSL standard. The SW is executed serially, i.e., no new SW thread frame will be generated when there is another SW thread frame being processed. THence, at most two thread frames are executed at any time, one from the DSTU thread and one from the SW thread.
[0223] Assumptions.
[0224] For the first step, we consider only two processors, one working at a higher voltage (V HIGH =3,4 or 5 V) and the other working at a lower voltage (V LOW =1 V). The reason to use the two processor architecture is that it can provide a way to exploit the concurrency inherent in the tasks and consume less energy than the one processor architecture. Regarding the latter point, if there is only one processor, it has to be fast enough to handle the heavy load bursts, and a fast processor is typically also a power greedy processor. However, heavy load bursts come only occasionally. At other times, all the tasks will still be executed on that fast, power greedy processor, though it needs not to be so fast. Even with modern power control technique that the fast processor can be shut down at idle time, it still consumes more energy than the set-up with the two processors working at different voltage, as we will prove later.
[0225] The maximal work frequency f max of the processors can be computed as below,
t delay ∝ CV dd I ∝ CV dd ( V dd - V th ) 2 = . C V dd ,
∴ f max ∝ V dd .
[0226] We assume also that the work frequency f is proportional to V dd . In CMOS digital circuits, most of the power dissipation comes from dynamic power dissipation. For one time cycle, the average dynamic power dissipation can be computed as,
P d ∝ V dd 2 f ∝ V dd 3 .
[0227] For our experiment, we use the values in Tab. 7.3.
[0228] Other assumptions taken here are: the processor is powered down automatically when it is idle and no context switch overhead is considered in the current experiments.
[0229] The timer threads work at a rigid 230 μs period and provide the needed control on the hardware, one for the transmitter and the other for the receiver. In the original design, the microcontroller of the timer will execute 128 instructions at most in one period, which is also its deadline. Most of the timer microcontroller instructions are testing, setting and resetting some signal line or register field, which can not be executed on a general processor like the ARM as efficiently as it is done on the specific microcontroller. Thus we assume each microcontroller instruction will take 5 general purpose processor cycles to execute it. Therefore, the worst case execution time of one timer is 64 μs on a 10 MHz processor.
[0230] The SW thread is a sequence of sporadic tasks, or events. They are released by the hardware part and have to be completed by their deadline. Another issue worth noticing is that they are executed in a strict sequential order, one task will only start after the previous one ends and no overlap will happen between them. The deadlines and execution times of these tasks are listed in Tab. 7.4, where the deadline is extracted from the initialization sequence of the ADSL standard and the execution time is measured on a 10 MHz processor.
[0231] Algorithms.
[0232] Two threads are presented in this experiment, one consists of the two DSTU and the other is the SW controller. For the SW thread, a thread frame is generated dynamically and it has only one thread node. For the timer thread, two thread nodes are generated every symbol period. A thread frame can cover one, two or even more symbol periods and we call it a time block (TB). The more symbol periods in a timer thread frame, the less processor utility ratio we will get due to the increasing idle time. But also less computation efforts are needed at run time since there are less thread frames to be considered by the dynamic scheduler now. There is another difference from what we state in the last section. The execution time and deadline of the SW thread, varying from tens to hundreds of symbol periods, is much longer than the timer TF time granularity, which is only a few symbol periods. Therefore, one SW TF will have to be scheduled simultaneous with many timer TFs so the SW TF is intersected into many pieces by them. Accordingly we changed the dynamic scheduling method a little. When no SW event is triggered, the dynamic scheduler will choose the lest energy consumptive scheduling in which all the timer thread nodes are executed on the low voltage processor. Whenever a SW event is triggered, the dynamic scheduler will find out the execution order of all the TFs involved to save the energy consumption as much as possible.
[0233] We use (L,H) pairs to represent a scheduling decision. L is the set of thread nodes assigned to the low voltage processor; H is the set of thread nodes on the high voltage processor. For instance, (1,1)+(s,_) means one DSTU timer thread node and the SW thread are assigned to L, the other DSTU thread node is assigned to H at that TB.
[0234] To formalize the problem, suppose we have n static scheduling options for one time block. For each option, C T,i and C S,i (i=1, 2, . . . , n) represent the time that can be used to execute the timer and SW thread in one TB respectively. Similarly, E T,i and E S,i (i=1, 2, . . . , n) represent the energy consumption for timer and SW part in one TB. We will schedule with a time granularity of TB. Suppose the execution time of the coming SW thread node is C and the deadline is D. If we have n possible choices for a TB and let l i (i=1, 2, . . . , n) represent the number of TBs for each choice in the scheduling, to find a feasible scheduling is to find a set of l i which can provide enough execution time for that task before the deadline meets. To find an optimal scheduling in energy cost is to choose one with the minimal energy consumption among these feasible schedulings. This can be restated as a constrained Integer Linear Programming (ILP) problem as below,
∑ i = 1 n l i · C S , i ≥ C , ( 6.14 ) ∑ i = 1 n l i ≤ D TB , ( 6.15 ) minimize : ∑ i = 1 n l i · ( E S , i + E T , i ) . ( 6.16 )
[0235] Eqn. 6.14 is the constraint on execution time for SW; Eqn. 6.15 makes sure that it is done before the deadline meets; Eqn. 6.16 is the optimizing objective function. By solving that ILP problem, we can get an energy optimal, deadline satisfying task schedule.
[0236] Experimental Results.
[0237] In total five cases are considered in our experiment.
[0238] Case 1.
[0239] Conditions:
[0240] 1. TB=1 symbol period;
[0241] 2. V LOW =1 V, V HIGH =3 V;
[0242] 3. The two timers and SW threads are scheduled independently.
[0243] The Eq. C S,i in Tab. 7.5 is the equivalent execution time on the 10 MHz processor.
[0244] The optimal schedule result derived from the ILP solver is shown in Tab. 7.6. It is interesting to notice that though task 4 and task 12 have the same execution time, the scheduling result and energy consumed are quite different because of their different deadlines. For a stricter deadline, more part of the thread frame will be executed on the higher voltage processor and that means more power. Task 7 and task 14 also have the same execution time but different scheduling.
[0245] Case 2.
[0246] Conditions:
[0247] 1. TB=1 symbol period;
[0248] 2. V LOW =1 V, V HIGH =3 V;
[0249] 3. The two timers are grouped together.
[0250] The difference between case 1 and case 2 can be seen in FIG. 7. 36 , where the shadowed areas represent the processor time occupied by the DSTU thread nodes. In case 2, the two timers are integrated in one group and scheduled as a unit. Though there is idle time in that group, it is not available to the processes outside that group. The optimal schedule result derived from the ILP solver is shown in Tab. 7.8.
[0251] Case 3. Conditions:
[0252] 1. TB=2 symbol periods;
[0253] 2. V LOW =1 V, V HIGH =3 V;
[0254] 3. The two timers are grouped together for two symbols.
[0255] All possible schedules of the timers in two symbol periods that make a reasonable distinction can be found in FIG. 7. 37 . The optimal schedule result derived from the ILP solver is shown in Tab. 7.10.
[0256] Case 4.
[0257] Conditions:
[0258] 1. TB=3 symbol periods;
[0259] 2. V LOW =1 V, V HIGH =4 V;
[0260] 3. The two timers are grouped together for three symbols.
[0261] The reason we change the higher voltage to 4V is that it is unschedulable with a 3V processor. The possible schedules of the timers for one TB is similar to case 3. The only difference is that one symbol, in which both timers are scheduled to L, is inserted between the original two symbols. The optimal schedule result derived from the ILP solver is shown in Tab. 7.12.
[0262] Case 5.
[0263] Conditions:
[0264] 1. TB=4 symbol periods;
[0265] 2. V LOW =1 V, V HIGH =5 V;
[0266] 3. The two timers are grouped together for four symbols.
[0267] For the same reason as in case 4, we change the higher voltage to 5V. The possible schedules of the timers for one TB are similar to case 3 except for the two inserted symbols. The schedule result derived from the ILP solver is shown in Tab. 7.14.
[0268] Further Analysis.
[0269] Checking the result above carefully one will find that the energy cost of task7 and task11 in case2 is higher than those in case3. That is because we have more scheduling options in one TB for case3, which can be interpreted as a less power costly scheduling result but with more effort in overhead and communication.
[0270] To get an idea of the energy cost versus different scheduling cases we can refer to Tab. 7.15. Remember case4 and case5 have a working voltage different from the first three cases to keep it still schedulable. To make a fair comparison, we change the high voltage of all cases to 5 V. The result is shown in Tab. 7.16. It can be found out that while the granularity of a TB increases, the energy consumption increases also. However, as mentioned before, the whole overhead cost will decrease since there are fewer TBs to be scheduled dynamically. We also computed the energy consumption tinder only one processor architecture. It's 18.3 when that processor works at 3 V and 51.2 when it works at 5 V. Compared with the one processor architecture, there is an energy saving of about 20% even at the biggest TB in case 5. This energy saving percentage varies with the system load. The heavier the load, the less the saving percentage because more work will be done on the high voltage processor. When all the tasks are done on the high voltage processor, it is reduced to the one processor case.
[0271] The overhead of the above dynamical scheduling process can be divided into two parts. First, the computation to find an optimal scheduling at the coming of a new TF; secondly, the effort to control the thread nodes when a TF is being executed. An MILP model is chosen here for the first part and the branch and bound approach is used to solve that problem.
[0272] Conclusions.
[0273] In this proposal, we present our approach of doing task concurrency management on a multiprocessor architecture for power saving consideration. The TCM is done in three steps, namely the concurrency extraction, the static scheduling and the dynamic scheduling steps. A static scheduling method is proposed to get an power optimal static scheduling for a thread frame under given time constraints or deadline. Varying the frame deadline will give a series of cycle budget and power cost tradeoff points, on which a dynamic thread frame scheduling will be done. At present, we used a MILP method for the dynamic scheduling. Other scheduling methods can be applied as well. This three step approach can bring flexibility and reduced design time to the embedded SW design. These techniques are applied to a ADSL modem application and some interesting results are derived. First, more than 20% power saving can be obtained. Second, we changed the granularity of a TF and demonstrate that a tradeoff exists between the dynamical scheduling overhead and scheduling optimality.
[0274] 6.4.2 A New Static Scheduling Heuristic and Its Experiment Results on the IM1 Player
[0275] In this section we will introduce a new static scheduling heuristic. Its major difference from existing algorithms are explained then. Finally, it is applied to the IM1 player. Experiment results are used to illustrate the above arguments. The example is again derived from the IM1-player. The part scheduled here is similar to the one illustrated in the previous section (cfr. 6.3.1).
[0276] Our approach can be applied to the multiprocessor platform without the need of changing the processor voltage dynamically. Given a multiple processor platform, i.e., the number of high-speed processors and low-speed processors, we aim at deriving an energy-cost vs time-budget curve. Compared with other scheduling algorithms, like MILP (mixed integer linear programming), our approach has the following difference. In the first place, our heuristic derives a set of working points on the energy-cost vs time-budget plane instead of only one point. These working points range from the most optimal performance point within that given platform to the point barely meeting timing constraints. For a given platform, these working points form a Pareto curve, which enables designer to trade off between cost(energy-consumption) and performance(time-budget). For example, when combining subsystems into a complete system or during the dynamic scheduling stage, we need to select working points of subsystems and combine them into a globally optimal working point. Existence of these different working points is mostly due to the different thread node to processor assignments (some of it is due to idle time in the schedule). As a result this heuristic deal with both a crucial assignment problem and ordering problem. Secondly, it uses an intelligent policy to prune the search space heavily. Hence, the computation complexity is reduced. Thirdly, it does not need to change the processor voltage dynamically.
[0277] To achieve the above objective, the heuritic uses the following two criteria to make the assignement and scheduling decisions. The first criterion is the self-weight of a thread node. It is defined as the execution time of the thread node on the low-speed processor. The larger the self-weight of a thread node, the higher its priority to be mapped on a high-speed processor. The second criterion is the load of a thread node. If some thread nodes are depending on a thread node, the sum of the self-weights of all the dependent thread nodes is defined as the load of the thread node. It is worth noting that “dependent” means control dependence. The more load a thread node has, the earlier it should start to execute.
[0278] From the above criteria, when a processor is available, the following strategy takes care of selecting a candidate thread node.
[0279] 1. When a thread node is dominant both in the self-weight and load over the other candidate thread nodes, it will be scheduled first.
[0280] 2. When one thread node has a dominant self-weight and another thread node has a dominant load, either of them can be scheduled first. By alternating their order different points on the energy-cost vs time-budget plane can be generated.
[0281] It is better to realize that the heuristic implicitly includes energy considerations. Because for a given processor, the energy consumption is directly related to the execution time. The self-weight and load in the heuristic are merely two interpretations of execution time from differen perspectives. Applying this heuristic to the IM1 player will be discussed in the following section. Even though it seems relatively simple, it turns out to be very effective for scheduling the tasks in the MPEG-4 IM1 player.
[0282] When applied to the IM1 player, the heuristic the task graph of the IM1 player as input. Two parellel ARM7TDMI processors, running at 1V and 3.3V respectively, are used to illustrate the scheduling. The main constraint for scheduling is the period. It starts at the reading of one VOP 2 data and expires at the end of the decoding of the data. Energy is the cost function used here. Currently, it includes both the processor energy and DTS energy. The DTS energy is mainly used for buffering between the reading and decoding of the data.
[0283] The period we have measured for the initial VI version is around 2000 μs per packet. Such a long period is caused by reserving and releasing semaphores. The period varies due to the jitter of the operating system. After our initial transformations, we have produced version V2 of the task graph.
[0284] Without loss of generality, we assume that one VOP data consists of two packets of data. The current implementation dictates that the two packets be read and decoded sequentially. That is, only after one packet is read and decoded, a second packet can be read and decoded. Due to such a limitation, we can only reduce the period by executing some nodes on a high Vdd processor.
[0285] For one node, we use t L and t H to denote the its execution time on the 1V ARM7TDMI and 3.3V ARM7TDMI respectively and Δt to denote the difference between these two execution times. Similary, we use E L and E H to denote its cost of the processor energy to run on 1V ARM7TDMI and 3.3 ARM7TDMI and ΔE to denote the energy difference. Our calculations are based on the following formulae.
Δ t = t L - t H = ( 1 - 1 3.3 ) t L ( 6.17 ) Δ E = E H - E L = ( 3.3 2 - 1 ) E L ( 6.18 )
[0286] For transformed graph V2, we start scheduling by assigning every node to the low Vdd processor and moving selected nodes to high Vdd processor when a shorter period is needed. We end up at assigning every node to the high Vdd processor. The period and total energy cost of the Pareto-optimal points in the search space are shown in FIG. 7. 34 .
[0287] After additional transformations that lead to V3, we remove the implicit sequential restriction in the code. Consequently, it is feasible to read and decode more than one data packet concurrently. We can better utilize the two processors by exploiting the concurrency and hence we can shorten the period with less energy cost.
[0288] Two scheduling examples of the V3 task graph are shown in FIG. 7. 35 . We use N 1A , N 1B , . . . and N 2A , N 2B , . . . to denote the nodes for reading and decoding of the two data packets respectively. FIG. 7. 35 shows that the period varies significantly due to different scheduling. The scheduling result is shown in FIG. 7. 34 .
[0289] [0289]FIG. 7. 34 shows that scheduling point 2, 7 and 8 are not on the Pareto curve because point 3 and 9 offer a shorter period with a lower energy cost. It is clear that version V3 is better than version V2.
[0290] Notice that reading two data packets concurrently has a higher memory energy cost than reading the packets sequentially since a larger buffer is needed. In the graph, the total energy cost for version V3 is initially higher due to the above reason. At smaller period points, scheduling the transformed graph V3 offers a shorter period with a lower energy cost.
[0291] 6.4.3 Management of Data Structures at the Task-Level
[0292] The data used by the tasks needs to be managed and mapped efficiently on the target platform at the task-level. More in particular, we propose several transformations that optimize the energy consumption and memory occupation of data structures which dependent on the dynamic behavior of the application. Note that these transformations will be applied on a system using the grey-box model presented above. The main advantage of this model is that is exposes all relevant information about the dynamic behavior and the most important data structures of the application.
[0293] Reducing the Dynamic Memory Requirements
[0294] When developing an initial model of a system, specification engineers normally spend neither time nor energy to accurately use dynamic memory. They are mainly concerned with the functionality and the correctness of the system. As a result, the software model is often very memory inefficient. However, for the design engineers it afterwards becomes an almost unmanageable and at least an error-prone process to improve the dynamic memory usage due to dangling pointers and memory leaks. Therefore, they will either redesign the system from scratch or use the same system but increase the memory, which results in a more power hungry architecture. We will present two formalizable transformations that allow us to systematically reduce the amount of dynamic memory required by the application. The benefit of these transformations can be exploited on different multi-processor platforms. Therefore, we will discuss the influence of the platform on the DM requirements of an application and we will explain how these can be relaxed.
[0295] Control/Data-Flow Transformations Enabling a Reduction of the Dynamic Memory Requirements
[0296] With the first transformation we reduce the life-time of the dynamically allocated memory by allocating the memory as late as possible and deallocating it as soon as possible. As a result of our approach, we are able to increase the storage rotation, which can significantly reduce the amount of memory required by the application. Indeed, in most applications memory is allocated in advance and only used a long time after. This design principle is applied to obtain flexible and well structured code which is easy to reuse. Although this can be a good strategy to specify systems on a powerful general purpose platform, the extra memory cost paid is not acceptable for cost-sensitive embedded systems. This allocation policy could also be implemented using a garbage collector. However, transforming the source code instead of relying on a run-time garbage collector to implement this results in a lower power consumption. The transformation acts as an enabling step for the second transformation and the task-ordering step discussed below.
[0297] By postponing the allocation we are able to gather more accurate information on the precise amount of memory needed. This information can be used to optimize the amount of memory allocated for each data type. The ratio behind this transformation is that specification engineers often allocate conservatively large amounts of memory. In this way, they try to avoid cumbersome and difficult debugging. They hereby forget that it is much harder for implementation engineers to re-specify afterwards the amount of memory as they do not have the same algorithmic background. For the same reason, automation of this transformation is particularly hard.
[0298] We have applied both transformations on the dynamically allocated buffers in the IM1-player. These buffers are used to store the input and output of the compression layer. The size of the input buffers is transmitted in the OD data packets; the size of the output buffers is fixed at design-time and differs for each decoder type.
[0299] We have profiled the time-instants at which each buffer is (de)allocated and is first(last) used. All the input buffers are allocated and freed at the same time. However, on the original one processor-platform, the buffers are used sequentially. As a consequence, by reducing the life-time of these buffers it is possible to overlap them and significantly decrease the amount of memory needed. This principle is illustrated on the left part of FIG. 7. 38 .
[0300] By analyzing the memory accesses to the allocated memory, we have found out that a large part of the dynamically allocated output buffers is never accessed. By applying our first transformation, we are able to reduce the output buffer size by making it data dependent. Instead of using worst case sizes, the more average data dependent sizes required by the input stream can now be used (see right part of FIG. 7. 38 ).
[0301] Constraints on Static and Dynamic Task-Schedule Reducing the Dynamic Memory Cost on a Multi-Processor Platform
[0302] After improving the characteristics of the application with the transformations mentioned above, its tasks still need to be assigned and scheduled on a ‘platform’. By constraining the task-schedule of the application (e.g. scheduling the task that requires the largest amount of memory first) it is possible to avoid consecutive (de)allocations of the same memory. In this way, not only some memory accesses can be avoided (and as a result power saved), but also the fragmentation of the memory can be reduced.
[0303] In addition, when exploiting the parallelism inside the application, the amount of memory needed by the application will normally increase proportional to the amount of processors. This relation can be improved by avoiding that two tasks both using a large amount of memory, are executed simultaneously. Our transformations applied prior to this step will relax the constraints on the task-schedule.
[0304] We will illustrate this with the same example as above. Initially, it is useless to reorder the different tasks to decrease the DM cost of the input-buffers. All buffers have the same life-time and no gain can be made by reordering the different tasks. After applying the enabling transformations discussed above, we obtain more freedom to reorder(or constrain) the task-schedule to decrease the DM cost. E.g. we can avoid decoding simultaneously the wavelet decoders that require much memory. As a consequence, the total amount of required memory increases less than proportional to the amount of parallelism (see FIG. 7. 39 ).
[0305] Experiments and Results
[0306] In this section we will prove quantatively the results of our transformation methodology. In a first part we will present the benefit of our transformations on the input buffers. In a second part we will briefly explain the potential benefit of our methodology on the output buffers.
[0307] We will schedule the IM1-player on a representative platform consisting of two software processors with extra hardware accelerators added to decode the AV-data. The system layer of the player consists of three tasks running on the software processors, i.e. the delivery layer, BIFS- and OD decoder. The two parallel SA110 processors running both at 1V are used to illustrate the scheduling. The main constraint for scheduling is the time-budget, i.e. 30 ms to render one frame. The two SA110 processors consume 40 mW each. The energy consumed by the hardware accelerators is estimated based on realistic numbers that we obtained by measuring the a wavelet decoding oriented chip that we have developed at IMEC. The cost of the memory is calculated based on recent memory-models supplied by vendors (Alcatel 0.35u DRAM for the embedded memory and Siemens Infineon DRAM for the external memory).
[0308] In a first experiment we have scheduled the IM1-player using only one hardware accelerator. We have added afterwards an extra one to improve the performance of the system and decode more objects per frame. We have compared all our results with the performance of the initial specification mapped on the same platform.
[0309] The results in Tab. 7.18 and 7.17 clearly show the potential benefit of the transformations as they allow us to reduce the global power cost(including both processor and memory cost) with almost 20%. Moreover, this methodology still can be applied on other parts of the player and does not need to be restricted to the input buffers only. We have obtained this power gain because we are able to significantly reduce the amount of memory required by the application. As a consequence, the data can be stored on embedded DRAM instead of on off-chip DRAM. We believe that two reasons make our approach scalable to future applications: if embedded DRAM would become available that is large enough to contain the initial data structures, our transformations will still be needed because the power consumption of embedded DRAM scales at least super logarithmic with its size. Moreover, we believe that the amount of data required by the applications will increase at least proportional to the size of embedded DRAM.
[0310] As indicated above, the buffer size would normally increase proportionally with the amount of parallelism. By constraining the schedule this can be avoided. The results for a two hardware accelerator context are represented in Tab. 7.18. One can also derive from Tab. 7.17 and Tab. 7.18 that the fraction of the memory cost increases in the total energy budget when more parallelism is exploited in the system. This illustrates the importance of these constraints on highly parallel platforms.
[0311] In this final paragraph we present the effect of our transformations on the output buffers. We are able to significantly reduce the size of these buffers, i.e. from 750 kB to 105 kB. Consequentely, it further reduces the power cost of the memory accesses and allows us to embed the IM1 protocol on a portable device.
[0312] Conclusion
[0313] In this paper we have presented several systematic data/control flow transformations for advanced real-time multi-media applications which reduce the power (area) cost of the dynamically allocated memory or increase the performance of the system. The first transformation has reduced the life-time of the dynamically allocated data structures. As a result, the memory rotation could be significantly increased which reduces the required amount of memory. It also functioned as an enabling step for the second transformation, in which we have defined more accurately the amount of memory needed for each data structure. Finally, we have given some constraints which help to relax the effect of parallel execution of tasks on the increasing buffer cost. We have illustrated these techniques with examples extracted from a real multi-media application, the MPEG4 IM1-player. They allowed us to reduce the energy consumption of the memories with at least a factor of 5. As a consequence, the global power cost of a significant part of this particular application has decreased with 20% without even touching the other subsystems.
[0314] 6.5 Conclusion
[0315] It is clear from the description and FIG. 7. 1 that the invented design flow differs from the prior art flows as it include an extra task concurrency optimization step being located before hardware/software co-design. Further the new design flow works on a grey-box model, containing only part of the logical operations and the co-design step starts of with a partial scheduled description. The TCM step also generates a real-time operating system and a dynamic scheduler therefor. FIG. 7. 2 illustrates that the TCM optimization step comprises of a design-time and run-time step. Also extra step, such as grey-box description extraction, dynamic memory management, task-level data transfer and storage, and task concurrency improvement steps are indicated. It is shown that the static or design-time step generates static schedules and pareto information, being used within the run-time scheduler. FIG. 7. 3 shows a possible implementation of the real-time operating system with a dynamic scheduler, accepting a request for a new schedule. A new task is loaded. For each of the tasks on the list on alive tasks a subset of all possible intra-task schedules, more in particular the Pareto optimal ones, are loaded. The dynamic scheduler selects for each of these alive task one schedule. The selected schedules define an overall schedule for the alive tasks. This schedule is executed, starting with executing the first scheduled node of the first scheduled task. | A system and method of designing digital system. One aspect of the invention includes a method for designing an essentially digital system, wherein Pareto-based task concurrency optimization is performed. The method uses a system-level description of the functionality and timing of said digital system, wherein the system-level description comprises a plurality of tasks. Task concurrency optimization is performed on said system-level description, thereby obtaining a task concurrency optimized system-level description, including Pareto-like task optimization information. The essentially digital system is designed based on said task concurrency optimized system-level description. In one embodiment of the invention, the description is includes a “grey-box” description of the essentially digital system. | 6 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims priority to U.S. Provisional Patent Application Ser. No. 61/748,561, filed Jan. 3, 2013, is a continuation-in-part of U.S. patent application Ser. No. 13/432,068, and is a continuation-in-part of U.S. patent application Ser. No. 14/146,798, entitled “Inflatable Foot Cushion”, filed Jan. 3, 2014, which is incorporated herein by reference.
BACKGROUND
[0002] The present invention relates generally to the field of inflatable devices for supporting the human body, and more particularly is concerned with a novel improved inflatable foot cushion to counter the force amplifications experienced by the foot, and particularly the heel area of the foot, when the body is in the supine position.
[0003] In the supine position, the foot assumes the shape of a wedge that tapers from the toes down to the heel. The mechanical force amplifications that are typically associated with a wedge are therefore also experienced by the wedge-shaped foot. The heel area, and more specifically the points of contact between the heel area and the substrate upon which the body is lying in the supine position, experiences mechanical force amplifications that are analogous to those experienced by the working edge of the typical wedge. In addition, when in the supine position, the lower legs function as levers with the heel areas serving as fulcrums, further amplifying the mechanical forces acting upon the heel areas.
[0004] The recognition that heel ulcers are caused by such mechanical forces (pressure, shear and frictional stresses) on the heel became clinically significant in the early 1980's. Since that time it has been found that offloading mechanical forces on the heel is the ideal way to prevent a pressure ulcer of the heel from developing (see NPUAP and EPUAP Guidelines). During the era of using pillows to offload mechanical forces on the heel, the occurrence of pressure ulcers of the heel continued to increase. Pressure ulcers of the heel are now running a close second to sacral pressure ulcers. When considering the deep tissue injury component of the pressure ulcer, pressure ulcers of the heel are now first in occurrence (see Vangilder, MacFarlane, Harrison, Lachenbruch and Meyer 254-261).
[0005] In 1994, a three-chambered inflatable foot cushion was patented (Inflatable Foot Cushion of U.S. Pat. No. 5,328,445). The prevention and treatment of pressure ulcers of the heel and other types of foot wounds have been exceptional when this patented inflatable foot cushion has been in use. The foot resting chamber of that device was constructed to resemble the keel of a boat. The objectives of the two main inflatable chambers of the patented inflatable foot cushion that defined the foot resting chamber were the offloading the mechanical forces on the heel; the giving of symmetrical static air support to the calf, ankle and foot; and ( 3 ) the supporting of the sole of the foot to prevent foot drop and resultant injury. The third main chamber of that patented inflatable foot cushion was an independent chamber ( 16 ) that was used beneath the two main chambers as an accessory chamber to elevate the inflatable foot cushion.
[0006] In 2011, an improved inflatable foot cushion over the Inflatable Foot Cushion of U.S. Pat. No. 5,328,445 was disclosed in U.S. patent application Ser. No. 13/432,068.
SUMMARY
[0007] The present invention are further improvements to the inflatable foot cushion of pending U.S. patent application Ser. No. 13/432,068, and to the Inflatable Foot Cushion of U.S. Pat. No. 5,328,445, which are both incorporated herein by reference in their entireties. The novel improvements of the present invention relate to the independent inflatable chamber ( 10 ) of pending U.S. patent application Ser. No. 13/432,068, and to the inflatable cushion ( 16 ) of U.S.
[0008] U.S. Pat. No. 5,328,445, which improvements provide better protection of the Achilles' tendon areas of patients who wear the improved inflatable foot cushion ( 21 ) of the present invention (see FIG. 9 ); provide for better unloading of pressures on the heels of patients; that provide for reduced left and right lateral rotations of the ankles of patients; and that provide for less stress on the materials of construction upon rotation of the improved inflatable chamber ( 22 a ) under the improved inflatable foot cushion ( 21 ) of the present invention.
[0009] One embodiment of the improved inflatable foot cushion of the present invention to reduce the force amplifications upon the heel of a foot received therein when the body is in a supine position is the improvement comprising means for increasing the volume of the inflatable chamber of the inflatable foot cushion that pivotally swings under the inflatable foot cushion to provide increased support for the inflatable foot cushion when it is placed upon a substrate.
[0010] Another embodiment of the improved inflatable foot cushion of the present invention to reduce the force amplifications upon the heel of a foot received therein when the body is in a supine position is the further improvement comprising means to improve the pivotal axis about which the larger volume inflatable chamber is pivotally swung under the inflatable foot cushion of the present invention to reduce the bunching of the construction material.
[0011] Another embodiment of the improved inflatable foot cushion of the present invention to reduce the force amplifications upon the heel of a foot received therein when the body is in a supine position is the further improvement comprising means to increase the volume of the main chamber of the inflatable foot cushion in the direction of the larger volume inflatable chamber whereby two lateral bladders are created on either side of the main chamber volume expansion and between which the larger volume inflatable chamber is cradled when the larger volume inflatable chamber is pivoted under the inflatable foot cushion which thereby provides improved lateral stability to the inflatable foot cushion.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The present invention will be understood more fully from the detailed description given hereinafter and from the accompanying drawings of the preferred embodiment of the present invention, which, however, should not be taken to limit the invention, but are for explanation and understanding only.
[0013] In the drawings:
[0014] FIG. 1 is a right side elevation view of the novel inflatable foot cushion of pending U.S. patent application Ser. No. 13/432,068.
[0015] FIG. 2 is a left side elevation view of the inflatable foot cushion of FIG. 1 .
[0016] FIG. 3 is a top plan view of the inflatable foot cushion of FIG. 1 .
[0017] FIG. 4 as a right side perspective view of the inflatable foot cushion of FIG. 1 .
[0018] FIG. 5 is a right side perspective view of the inflatable foot cushion of FIG. 1 .
[0019] FIG. 6 is a front perspective view of the inflatable foot cushion of FIG. 1 .
[0020] FIG. 7 is a front end view of the inflatable foot cushion of FIG. 1 .
[0021] FIG. 8 is an exploded top plan view of the inflated inflatable foot FIG. 1 showing the relationships of its constituent parts.
[0022] FIG. 9 is an exploded top plan view of the novel inflated inflatable foot cushion of the present invention showing the relationships of its consistent parts.
[0023] Corresponding reference characters indicate corresponding parts throughout the several views. The exemplary embodiments set forth herein are not to be construed as limiting the scope of the invention in any manner.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0024] The present invention will be discussed hereinafter in detail in terms of various exemplary embodiments according to the present invention with reference to the accompanying drawings. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be obvious, however, to those skilled in the art that the present invention may be practiced without these specific details. In other instances, well-known structures are not shown in detail in order to avoid unnecessary obscuring of the present invention.
[0025] Thus, all of the implementations described below are exemplary implementations provided to enable persons skilled in the art to make or use the embodiments of the disclosure and are not intended to limit the scope of the disclosure, which is defined by the claims. As used herein, the word “exemplary” or “illustrative” means “serving as an example, instance, or illustration.” Any implementation described herein as “exemplary” or “illustrative” is not necessarily to be construed as preferred or advantageous over other implementations. Moreover, in the present description, the terms “upper”, “lower”, “left”, “rear”, “right”, “front”, “vertical”, “horizontal”, and derivatives thereof shall relate to the invention as oriented in FIG. 1 .
[0026] Furthermore, there is no intention to be bound by any expressed or implied theory presented in the preceding technical field, background, brief summary or the following detailed description. It is also to be understood that the specific devices and processes illustrated in the attached drawings, and described in the following specification, are simply exemplary embodiments of the inventive concepts defined in the appended claims. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise.
[0027] Referring now to FIG. 8 , which is an exploded top plan view of the inflatable foot cushion ( 1 ) of U.S. patent application Ser. No. 13/432,068, FIG. 8 illustrates the relationships of the novel constituent parts of that inflatable foot cushion, and which also illustrates how two pliable plastic sheets have been joined together by conventional means to form the novel inflatable chambers and straps of the inflatable foot cushion ( 1 ) of U.S. patent application Ser. No. 13/432,068.
[0028] Referring to FIG. 2 , there is one inflation port ( 12 ) for all of the air inflatable chambers shown in FIG. 8 , all of which are in fluid communication with each other, with one exception. FIG. 2 also illustrates an inflation port ( 12 ) for independent air inflatable chamber ( 10 ), which is not in fluid communication with the other cambers illustrated in FIG. 8 , and which is of the same size and has the same functionality as does independent air inflatable cushion ( 16 ) of the Inflatable Foot Cushion of U.S. Pat. No. 5,328,445. The only difference between the independent inflatable chamber ( 10 ) of U.S. patent application Ser. No. 13/432,068, and the inflatable cushion ( 16 ) of U.S. Pat. No. 5,328,445 is that cushion ( 10 ) is kept in it adjustable positions by hook and loop fasteners ( 13 , 14 ).
[0029] One of the improvement of the inflatable foot cushion ( 1 ) of U.S. patent application Ser. No. 13/432,068 is the addition of air-inflated, adjustable calf straps ( 2 ) that secure the inflatable foot cushion ( 1 ) to the calf, ankle and foot of a patient, which air inflated calf straps effectively protect a patient's skin of the calf over the tibia when the calf is secured within the inflatable foot cushion ( 1 ) by the inflated adjustable calf straps ( 2 ). This is accomplished by filling the individual inflatable calf straps ( 3 , 4 , 5 ) with static air, each strap being formed, as are all other static air chambers of the inflatable foot cushion ( 1 ), by two pliable plastic sheets joined together by conventional means to form inflatable chambers within the calf straps ( 3 , 4 , 5 ). Filling the calf straps ( 3 , 4 , 5 ) with air moves the welded joints ( 7 ) of the two pliable plastic sheets that were joined together to form the air chambers within the calf straps ( 3 . 4 , 5 ) well away from a patient's skin of the calf over the tibia when the calf straps ( 3 , 4 , 5 ) are each independently snugged up against the skin of the calf over the tibia to secure the improved inflatable foot cushion ( 1 ) of U.S. patent application Ser. No. 13/432,068 about the calf, ankle and foot of the patient. The inflatable calf straps ( 3 , 4 , 5 ) are each connected at one end thereof to one downwardly-sloping side ( 16 ) of the main chamber ( 6 ) in fluid communication with the main chamber ( 6 ), and at the other end each calf strap ( 3 , 4 , 5 ) is adjustably attached to the opposite downwardly sloping side ( 17 ) of the main chamber ( 6 ) with hook and loop fasteners ( 13 , 14 ).
[0030] By this design of the secured inflated calf straps ( 3 , 4 , 5 ) of the inflatable foot cushion ( 1 ) of U.S. patent application Ser. No. 13/432,068, the calf and ankle are fully supported and kept snug through 360 degrees by equalized static air pressures (cf., Boyles Law and Paschal Principles). Not only do the air-filled calf straps ( 3 , 4 , 5 ) deliver non-gradient air pressure to the calf, but as mentioned above, they also keep the sealed construction edges ( 7 ) of the air-filled straps ( 3 , 4 , 5 ) away from the patient's skin of the calf over the tibia. Neither of these design features was present in the Inflatable Foot Cushion of U.S. Pat. No. 5,328,445.
[0031] Another improvement of the inflatable foot cushion ( 1 ) of U.S. patent application Ser. No. 13/432,068 is the sloped-downward design of the sides ( 16 , 17 ) of the main chamber ( 6 ), which slope downwardly from the calf to the ankle areas of the main chamber ( 6 ) (see FIG. 1 ). The use of the air filled calf straps ( 3 , 4 , 5 ) allows this lower side profile of the sides ( 16 , 17 ) of the main chamber ( 6 ) to be used effectively to provide for better ambient air circulation around the calf and ankle area, which in combination with through holes ( 11 ) in the sides ( 16 , 17 ) provides for better ambient air control (both temperature and moisture control) around the patient's calf and ankle. The inflatable foot cushion ( 1 ) of U.S. patent application Ser. No. 13/432,068 thus permits more ambient air to enter the inflatable cushion and surround the patient's calf and ankle areas. To improve ambient air circulation, calf strap ( 5 ) may be freed from its securing hook and loop fasteners ( 13 , 14 ) on side ( 17 ) of the main chamber ( 6 ) and temporarily the hook faster ( 14 ) of calf strap ( 5 ) may be attached to loop fastener ( 20 ) shown on side ( 17 ) (see FIG. 2 ) of main chamber ( 6 ).
[0032] In testing done to date, the lower side profile of the downwardly-sloping sides ( 16 , 17 ) of the main chamber ( 6 ) of U.S. patent application Ser. No. 13/432,068 also reduced the chance for lateral rotation of the patient's calf, ankle and foot within the main chamber ( 6 ), and reduces the chances for an over extension or flexion of the patient's knee and a lateral rotation of the patient's hip. This was a major improvement over the Inflatable Foot Cushion of U.S. Pat. No. 5,328,445, as that device is balloon-like in its overall structure, and it therefore had a tendency to roll from side-to-side when either over or under inflated with air. The lower profile and downwardly sloping sides ( 16 , 17 ) also allow patients wearing the inflatable foot cushion ( 1 ) of U.S. patent application Ser. No. 13/432,068 to articulate their ankles and to move their foot fore and aft while it is snuggly embraced within the inflatable foot cushion ( 1 ) of U.S. patent application Ser. No. 13/432,068.
[0033] Additional improvements of the inflatable foot cushion ( 1 ) of U.S. patent application Ser. No. 13/432,068, discussed below, relate to the prevention of the inflatable foot cushion ( 1 ) from spinning on its longitudinal axis, which compromises the desired patient calf, ankle and foot positioning within the device, and which occurred at times when the Inflatable Foot Cushion of U.S. Pat. No. 5,328,445 was in use.
[0034] Another improvement of the inflatable foot cushion ( 1 ) of U.S. patent application Ser. No. 13/432,068 is a novel air filled and adjustable foot strap ( 9 ) that is connected in fluid communication with the foot chamber cushion ( 19 ) of main chamber ( 6 ), and it passes from foot chamber cushion ( 19 ) to foot chamber cushion ( 18 ) where it is adjustably attached to foot cushion chamber ( 18 ) of the main chamber ( 6 ) with hook and loop fasteners ( 13 , 14 ). In this manner, the air-filled and adjustable foot strap ( 9 ) covers the patient's skin on top of the foot positioned within the main chamber ( 6 ), which prevents the patient's calf, ankle and foot from inadvertently slipping out of the inflatable foot cushion ( 1 ) when in use. The foot strap ( 9 ) also allows for a complete customizable fitting of a patient's foot within the inflatable foot cushion ( 1 ). This novel feature can be compared to the lacing or strapping of normal footwear to the patient's foot.
[0035] Another improvement of the inflatable foot cushion ( 1 ) of U.S. patent application Ser. No. 13/432,068 is the novel design of the adjustable, inflatable foot sole cushion ( 8 ) that is adjustable in two parts (see FIGS. 6 & 7 ) with hook and loop fasteners ( 13 , 14 ) to match the contours of the sole of a foot within the inflatable foot cushion ( 1 ). The adjustable and inflatable two-part foot sole cushion ( 8 ) has one part thereof in fluid communication with foot chamber cushion ( 18 ) and the other part in fluid communication with foot chamber cushion ( 19 ) and foot sole cushion ( 8 ) thereby allowing a more custom fit of the inflatable foot cushion ( 1 ) to the sole of a patient's foot. It is adjustable with large hook and loop fasteners ( 13 , 14 ) (see FIGS. 6 & 7 ), which also protects the sides of a patient's foot from being too tightly fit within inflatable foot cushion ( 1 ). The uniform shape of the foot sole cushion ( 14 ) of the Inflatable Foot Cushion of U.S. Pat. No. 5,328,445 was not able to accomplish this custom fit to the sole of a patient's foot.
[0036] The adjustable inflatable two-part foot sole cushion ( 8 ) also creates a desirably larger hole ( 15 ) in main chamber ( 6 ) for a patient's heel to reside within, unsupported (see FIGS. 1, 3 & 6 ), than the hole that was created in the Inflatable Foot Cushion of U.S. Pat. No. 5,328,445.
[0037] This fact, coupled with the functionality of foot strap ( 9 ) and foot sole cushion ( 8 ), which keep a patient's foot up, thereby preventing “foot drop” (see FIG. 1 ), also was thought to protect the entire Achilles' heel area, as well.
[0038] Furthermore, when the two-part foot sole cushion ( 8 ) is opened completely by disassociating the adjustable hook and loop fasteners completely ( 13 , 14 ) (see FIG. 7 ), the patient's foot sole is fully exposed, and the patient could then become ambulatory, moving from a bed to a chair, for example, while still wearing the inflatable foot cushion ( 1 ) of U.S. patent application Ser. No. 13/432,068, which was not a possibility with the Inflatable Foot Cushion of U.S. Pat. No. 5,328,445.
[0039] In testing to date, the third and fourth improvements disclosed in U.S. patent application Ser. No. 13/432,068, mentioned above, also assisted in preventing the spinning of the inflatable foot cushion ( 1 ) of U.S. patent application Ser. No. 13/432,068 on its longitudinal axis, which occurred at times when the Inflatable Foot Cushion of U.S. Pat. No. 5,328,445 was over or under inflated.
[0040] In summary, these foregoing improvements disclosed within the inflatable foot cushion ( 1 ) U.S. patent application Ser. No. 13/432,068 addressed the maintenance of proper anatomical positioning of the patient's calf, ankle and foot when in that inflatable foot cushion; they delivered a low profiled static air support through 360 degrees for the patient's calf, ankle and foot so that skin and soft tissue distortion, ischemia, lymphatic and interstitial fluid obstruction and reperfusion injuries were less likely to occur.
[0041] The following two tables summarize in tabular format the differences between the inflatable foot cushion ( 1 ) of U.S. patent application Ser. No. 13/432,068 (“2011 Device”) and the Inflatable Foot Cushion of U.S. Pat. No. 5,328,445 (“1994 Device”).
[0000]
TABLE I
1994
2011 Device
Delivers Static Air Support to
Yes
Yes
Offloads the Heel
Yes
Yes
Protects Achilles Tendon
Yes
Yes
Has Air Filled, Adjustable
No
Yes
Protects the Medial Malleolus
Yes
Yes
[0000]
TABLE II
Rating of Effectiveness 1-5
1994
2011 Device
Unloads the Heel
5
5
Delivers Non-Gradient Static
5
5
Addresses Microclimate
4
5
Prevents Foot Drop
3
4
Prevents Lateral Rotation
3
4
Prevents Over-Extension of
4
5
Safety of the Adjustable
4
5
Foot Compartment
2
5
Prevention of the CAF
3
5
Ease of Use
4
5
Cost Effective
5
5
(5 = Excellent-1 = Poor)
[0042] Referring now to the FIG. 9 , the novel improvements of the present invention that have been made to the inflatable foot cushion ( 1 ) of U.S. patent application Ser. No. 13/432,068, and to the Inflatable Foot Cushion of U.S. Pat. No. 5,328,445, include novel improvement to the hook and loop fastener ( 22 ), which is performing essentially the same function as it does on inflatable chamber ( 10 ) of U.S. patent application Ser. No. 13/432,068, and on inflatable cushion ( 16 ) of U.S. Pat. No. 5,328,445, but which is now decreased in its overall length in the present invention. This decrease in length of hook and loop fastener ( 22 ) of the present invention creates a larger inflatable chamber ( 22 a ) of the present invention, which increases the inflated volume size of chamber ( 22 a ) when it is pivoted under the novel inflatable foot cushion ( 21 ) of the present invention. This provides increased support for the patient's foot over any substrate on which the novel inflatable foot cushion ( 21 ) of the present invention is placed.
[0043] The next novel improvement of the inflatable foot cushion ( 21 ) of the present invention is the novel lateral seal ( 22 b ) that replaces the oval-shaped pivot point of inflatable chamber ( 10 ) of U.S. patent application Ser. No. 13/432,068, and the inflatable cushion ( 16 ) of U.S. Pat. No. 5,328,445. The novel lateral seal ( 22 b ) creates a much improved pivotal axis for the larger inflatable cushion ( 22 a ) of the present invention when it is pivoted underneath the novel inflatable foot cushion ( 21 ) of the present invention. The novel lateral seal ( 22 b ) also reduces the bunching of the material of construction that was present when inflatable chamber ( 10 ) of U.S. patent application Ser. No. 13/432,068, and inflatable cushion ( 16 ) of U.S. Pat. No. 5,328,445, were pivoted about their oval-shaped pivot points, which resulted in bunched material of construction that proved to be potentially damaging to the Achilles' tendon areas of patients who wore these inflatable foot cushions. The novel lateral seal ( 22 b ) of the present invention also gives better elevation to the heel of a patient who is wearing of the inflatable foot cushion ( 21 ) of the present invention because the novel lateral seal ( 22 b ) keeps the larger inflatable cushion ( 22 a ) at a greater height off of any substrate when it is pivoted about novel lateral seal ( 22 b ) under the novel inflatable foot cushion ( 21 ) of the present invention. This also puts less physical strain on the material of construction of the novel inflatable foot cushion ( 21 ).
[0044] The next novel improvement of the novel inflatable foot cushion ( 21 ) of the present invention is the extension ( 22 c ) of its main chamber ( 22 d ). This increases in the volume of main chamber ( 22 d ) providing more elevation of the main chamber ( 22 d ) over any substrate at the center of the novel inflatable foot cushion ( 21 ), and most importantly, it creates two lateral bladders ( 22 e ) between which inflatable cushion ( 22 a ) is cradled when the inflatable cushion ( 22 a ) is pivoted under the novel inflatable foot cushion ( 21 ) of the present invention. The two lateral bladders ( 22 e ) provide much improved lateral stability to the novel inflatable foot cushion ( 21 ) of the present invention since the two lateral bladders ( 22 e ) are at about the same height off of any substrate as is the inflatable cushion ( 22 a ), which prevents the novel inflatable foot cushion ( 21 ) from rocking left to right on the round-bottomed inflatable cushion ( 22 a ) when it is pivoted under the novel inflatable foot cushion ( 21 ) of the present invention.
[0045] The next novel improvement of the improved inflatable foot cushion ( 21 ) of the present invention is the smaller placation circle ( 220 . The smaller placation circle ( 220 increases the volume of the two lateral bladders ( 22 e ), and thus also increase the height of the novel inflatable foot cushion ( 21 ) off of any substrate on which it is placed, which better protects a patient's lower calf and Achilles' tendon areas while wearing the novel inflatable foot cushion ( 21 ). The key is that the placation circle ( 220 is now smaller, which enlarges the volume of the two lateral bladders ( 22 e ).
[0046] In summary, the medical advantages provided by the novel improvements of the inflatable foot cushion ( 21 ) of the present invention over the inflatable foot cushions ( 1 ) of U.S. patent application Ser. No. 13/432,068 and the Inflatable Foot Cushion of U.S. Pat. No. 5,328,445, include 1) better protection of the patient's Achilles' tendon areas; 2) better unloading of pressures on the patient's heels due to the increased elevation of the patient's heals off of substrates; and 3) left and right lateral rotation of the ankles of patients is avoided by two novel lateral cushions ( 22 e ) formed by expanding the main chamber ( 22 d ) of the improved inflatable foot cushion ( 21 ) of the present invention, which cradles and stabilizes the improved inflatable chamber ( 22 a ) of the present invention when it is pivoted under the improved inflatable foot cushion ( 21 ).
[0047] While this invention has been described with respect to at least one embodiment, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims. | An inflatable foot cushion comprising: an anterior side; a posterior side; an inflatable main chamber adapted to support with static air pressures the calf, ankle and foot of a body in a supine position, and an inflatable independent chamber. | 0 |
[0001] This application claims priority from provisional application serial No. 60/079,627 filed on Mar. 27, 1998.
FIELD OF THE INVENTION
[0002] The present invention is directed to a system and a method for carrying medical and/or personal information and, in particular, to a system and a method which utilizes a locket having a memory chip with the medical information stored therein, and a shoe adapted to carry the locket.
BACKGROUND ART
[0003] In the prior art, various means have been proposed for individuals to carry medical information on their person. One technique is the wearing of a medical alert bracelet. This technique is not universally accepted since many individuals do not like the stigma associated with wearing an indicator that an individual has a particular medical condition.
[0004] Other ways to carry medical information include lockets containing a written, typed or printed tabulation of a person's medical condition. These lockets could be used with necklaces, wrist bands, or other modes of attachment. One drawback with these systems is the limited amount of information that can be carried on a written or printed form.
[0005] Medical information can also be stored on cards which are held in an individual's wallet or purse. The cards may hold the information in printed form or electronic memory form. The problem with this technique is that many medical personnel are prohibited from searching an individual's wallet or purse for reasons of privacy. Thus, carrying medical information in these locations may not permit an emergency medical person to obtain the information if the person is incapacitated.
[0006] In view of the disadvantages associated with the prior art techniques noted above, a need exists to provide an improved system and method for carrying medical information for an individual. The present invention solves this need through the use of a low-cost locket which carries medical information in an electronic memory chip. The locket is designed to interface easily with readers that can access the electronic information. The invention also provides a system whereby the locket can be discretely stored on a person's shoe so that it is readily obtainable by emergency medical personnel.
SUMMARY OF THE INVENTION
[0007] A first object of the present invention is to provide an improved system and method for individuals to carry medical information.
[0008] Another object of the invention is to provide a shoe with a pocket associated therewith, the pocket sized to receive a locket carrying the medical information electronically.
[0009] Another object of the invention is a locket which is designed to interface with readers which can access the locket's electronically stored medical information.
[0010] Another object of the invention is the mode of configuring the device storing the electronic medical information to facilitate reading the information by an electronic reading device.
[0011] In satisfaction of the foregoing objects and advantages, the present invention includes a method of providing information about a user including the steps of providing a locket enclosing a memory chip, the memory chip storing information about the user. The locket is opened to expose a machine-readable portion of the memory chip. The machine-readable portion of the chip is fed into a reader to access the information stored in the memory chip. The locket can be stored in a pocket of a shoe and the locket and/or shoe can indicate the presence of the locket in the pocket by placing indicia on the pocket/locket representative of medical information. The locket can be secured to a portion of the shoe using a flexible line such as a chain or the like. The memory chip can be removed from the locket for reading, particularly by using a removable support linked to the locket, removal of the support permitting reading of the memory chip by the reader.
[0012] The invention also includes a system for carrying information of a user comprising a locket having a lid, opening of the lid exposing an inside portion of the locket. The memory chip is attached to the inside portion and has storage capacity to store information about the user. The memory chip has a machine-readable portion so that the information can be accessed by a reader. The system can also include means for attaching the locket to the user.
[0013] The system also comprises a shoe with a pocket, the pocket sized to store the locket. A means for attaching the locket to a portion of the shoe can also be provided such as a flexible member or the like, e.g., a chain, wire, cord, etc. In one embodiment, the locket comprises two halves, a surface of one half containing the memory chip and being aligned in generally the same plane with a surface of the other half when the locket is opened for memory chip reading. The memory chip can be mounted on a support that is extendable from the locket for memory chip reading. The support can be foldable for storing in the locket when the locket is closed. The locket and/or the shoe pocket can have a logo on an exterior surface thereof to indicate a medical condition.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0014] FIGS. 1 A- 1 E show a first embodiment of the inventive locket depicting a square shape with or without a logo. The locket shape is generally square in shape and is shown with a chain and connector ring in FIG. 1A. The locket 10 has an electronic memory chip 1 embedded in the surface 3 thereof. The locket is comprised of two halves 5 and 7 which can be opened and closed as shown in FIG. 1E.
[0015] A logo 9 can be placed on the outer surface 11 if so desired. FIG. 1B shows the locket partially obscured when placed in a pocket 13 .
[0016] FIGS. 2 A- 2 E show a similar locket, but having a circular shape with or without the logo 9 .
[0017] FIGS. 3 A- 3 E show a hexagonal-shaped locket with an alternative logo 14 on the outer surface thereof.
[0018] Referring to FIGS. 4 - 8 B, the locket shown in FIG. 1A is illustrated in greater detail. Whether the locket is round, square, or hexagonal, the side view is the same as is the mechanical structure. Generally, the square and hexagonal shapes are stronger than the circular shape due to hinge length. FIG. 5 more clearly shows the clasp 13 which hooks to the locket half 5 to keep the locket in a closed position. These figures also illustrate the chain attachment 15 .
[0019] [0019]FIG. 6 shows the locket completely opened. In this configuration, the distal end 17 of the locket half 5 can be easily inserted into an EPROM chip reader (not shown) so that the chip 1 can be read.
[0020] The square locket shown in FIGS. 4 - 8 B offer certain advantages in the length of the hinge 19 . The longer hinge as compared to the hinge shown in FIG. 2D offers more structural strength. The locket as shown in FIG. 7 can also have indicia on the inner surfaces 21 and 23 to assist a user when inserting the locket half 5 into a reader. The locket in FIG. 8 has the logo 9 on the outside.
[0021] It should be understood that any type of a memory chip can be used with the foldable locket shown in FIGS. 1 A- 8 B. The chip could be recessed as shown in FIG. 6 or placed on the surface 23 so that it is a partially raised condition, if so desired. In addition, other geometric shapes could be used besides the square, circle and hexagonal configurations shown in FIGS. 1 A- 3 E. However, these shapes are preferred since they would result in reduced manufacturing costs. Other mechanisms can be used in place of the clasp 13 to keep the halves 5 and 7 together as would be within the skill of the art, e.g., a pin and complementary sized receiving hole or the like.
[0022] The locket is preferably made of a plastic material so that it is low cost and lightweight. FIG. 4 shows exemplary dimensions. Of course, other materials could be used as would be within the skill of the art.
[0023] Using the locket entails first storing the necessary medical information on the chip 1 . This can be done at the appropriate medical center or office which has the means to receive the information, convert it into an electronic form and store it on the chip. These means are readily available and do not require further description for understanding of the invention. Once the information is stored on the chip, the individual can carry the locket with the information in any manner, for example, on a necklace, in a pocket, on a wristband or the like. The locket can also be carried as described below on a shoe. With the information stored in the chip, the locket can then be opened by a medical technician, doctor or the like when the carrier is incapacitated. The half 5 can then be positioned in the appropriate manner so that a reader can read the information and the individual can be treated in light of his/her pre-existing condition.
[0024] To solve the problem of discretely hiding the locket while still making it accessible to medical personnel, a shoe can be provided with a pocket. One embodiment of the shoe with pocket is shown in FIG. 9 wherein the actual pocket is formed either within the shoe interior or between the inner and outer shoe layers. In this embodiment, only the pocket slot 25 is visible. The locket 10 is shown secured via the chain 27 to the lace 29 . In this embodiment, the pocket can be outlined by stitching 31 and a logo 33 can be placed on the pocket surface 35 . The pocket can be sized so that at least a portion of the locket 10 extends outwardly therefrom so it can be grabbed by an individual for access to the electronic memory chip contained therein.
[0025] [0025]FIG. 10 shows an alternative shoe with pocket wherein the pocket is located on the exterior of the shoe. The pocket 39 shown in FIG. 10 is attached to the shoe by stitching 41 .
[0026] Alternatively, the pocket could be attached by a removable fastener arrangement such as hook and loop fasteners. In this embodiment, the pocket and the fastening means could be sold with a shoe and the purchaser of the shoe could then attach the fastening means of pocket to the shoe if so desired. The fastening means could be secured to the shoe with an adhesive or tape or other means so that the pocket can be secured to the shoe after purchase.
[0027] In yet another embodiment, the shoe could be manufactured with the fastening means as a part thereof and the pocket could then be removably attached thereto, if so desired.
[0028] [0028]FIG. 11 shows a further embodiment wherein the pocket 25 is associated with the shoe but lacks the stitching depicted in FIG. 9.
[0029] The pocket configuration shown in FIGS. 9 and 10 could vary. For example, the stitching outline shown in FIG. 9 could take on another shape, e.g., more oval, more angular or the like.
[0030] Another embodiment of the invention entails a unique method for securing the E2PROM chip to a locket for easier reading. FIGS. 12 - 17 show a memory chip assembly 50 comprising a support including a substrate 51 with the chip 53 thereon. The chip 53 can be part of a credit card type card which is typically sized at 54 mm×86 mm. The thickness of the chip on a typical card is 0.8 mm and the card is usually 1.2 mm thick. The chip could have a security lock if so desired. The actual measurement of the chip could be larger to fit within a given locket. The inserted chip could have different shapes. As noted above, one design is shown in FIGS. 12 - 17 . In this design, the substrate 51 is hinged to a base section 55 . The base section 55 comprises two parts, 57 and 59 , each separated by the crease or fold line 61 . The base section 57 is designed to attach to the inside surface 63 of a capsule or locket 65 , see FIG. 16. The attachment can be by an adhesive or the like. With base section 67 attached to the capsule surface 63 , the substrate 51 can be extended from the capsule recess as shown in FIG. 16 to permit the chip 53 to be read by a reader. With this folding action, 75% of the substrate 51 -base section 55 can be extended for chip reading. The chip can be glued to the substrate 51 .
[0031] Other arrangements could be utilized providing that the chip 53 can be removed from the recess 67 so that it can be read, while still being replaced with the folding action as illustrated in FIGS. 13 - 16 .
[0032] While the above listed embodiments illustrate a chip that is inserted into a reader, other chips can be used as would be within the skill of the art. For example, a chip which only needs to be placed in the vicinity of a reader could be used as part of the inventive locket, system and method of obtaining medical information, e.g., an electronic send-receive devices using airwaves. With these devices, the memory device can transmit the information to a receiver/reader rather than use electrical contact between the device and the reader. In addition, the memory capacity of the chip can vary, e.g., 4 K, 8 K, 10 K and more bytes.
[0033] The chip may also include an alignment feature 69 , see FIG. 16. This feature 69 is intended to ensure that the chip is aligned with the reader when accessing the medical information. Typically, the chip will have different segments 71 which engage respective contacts of the reader. The chip and reader must be properly aligned so that the contacts of the reader engage the right segments of the chip. The feature 69 ensures that the chip is aligned to mate with the reader in the proper orientation. Of course, the reader will also have some indicia so that the feature 69 is arranged with respect to the reader in the proper manner. Other means or indicia can be utilized to assure proper alignment between the reader and the chip can be employed as would be within the skill of the art.
[0034] While the invention is described in terms of storing medical information, any type of information can be stored in the electronic memory of the device described above, e.g., personal information, organ donor information or the like. As such, an invention has been disclosed in terms of preferred embodiments thereof which fulfills each and every one of the objects of the present invention as set forth above and provides new and improved system and method for carrying information about a user.
[0035] Of course, various changes, modifications and alterations from the teachings of the present invention may be contemplated by those skilled in the art without departing from the intended spirit and scope thereof. It is intended that the present invention only be limited by the terms of the appended claims. | A system and method for carrying personal and/or medical information includes a locket designed to contain a memory electronic device to store information about the user. The locket is design to be opened to provide ready access to a machine readable portion of the memory device by a reader. The locket is combined with a pocket in a shoe to carry the locket unobtrusively. The locket and pocket can include a logo which will alert medical or other emergency personnel as to the existence of the locket during an emergency. | 6 |
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application claims the priority of German Patent Application, Serial No. 10 2005 041 021.9, filed Aug. 29, 2005, pursuant to 35 U.S.C. 119(a)-(d), the content of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to an adaptive crash structure for a vehicle body or chassis of a motor vehicle.
[0003] Nothing in the following discussion of the state of the art is to be construed as an admission of prior art.
[0004] Heretofore, complex metal castings have been used in front or rear zones of a motor vehicle, in particular when crash structures and chassis parts are involved. Employing castings of aluminum, aluminum alloys or other suitable cast materials result in weight saving while still allowing realization of complex structures. In order to meet the demand for resilience in the event of impact, relatively thick-walled and rigid castings have been combined to date with thin-walled deformation members, for example through incorporation of an extrusion profile using a welding operation. The connection between castings and interposed deformation member is difficult to implement as several single parts have to be separately manufactured, handled, positioned, and welded together. The welding operation generates heat which causes parts to warp so that effective surfaces and boreholes require refinishing after assembly to stay within admissible tolerances. Still, such structures tend to warp even after machining and in addition require also special protection for transport.
[0005] It would therefore be desirable and advantageous to provide an improved adaptive crash structure which obviates prior art shortcomings and which is easy to manufacture while functioning reliably in the event of a crash.
SUMMARY OF THE INVENTION
[0006] According to one aspect of the present invention, an adaptive crash structure of a vehicle body or chassis of a motor vehicle includes a first metal casting, a second metal casting, a deformation element in the form of a metal casting for absorbing energy, with the deformation element interconnecting and formed in one piece with the first and second metal castings through a casting process, wherein the deformation element is comprised of a plurality of funnel-shaped wedge bodies disposed in succession, with neighboring wedge bodies being connected through intervention of a predetermined breaking web, wherein each wedge body is defined by a diameter, with the diameters of the wedge bodies sized to allow the wedge bodies to move telescopically into one another when a limit stress is reached and the predetermined breaking webs rupture so as to effect a tight intergrip of the telescoping wedge bodies in a self-locking manner.
[0007] The present invention resolves prior art shortcomings by constructing the deformation element in one piece with the metal castings. In other words, the structure of deformation element and metal castings can be made monolithically through a casting process in the absence of any welding process. As a result, the number of parts is significantly reduced. There is no need for a complicated separate manufacture, positioning, and of course a previously required jointing operation, i.e., welding. The absence of welding heat also means less warping of the structure. The deformation element of the invention is able to meet required crash standards as a consequence of the arrangement of sequentially disposed wedge bodies and the provision of a predetermined breaking web between neighboring wedge bodies. Once, a limit stress is encountered, the predetermined breaking webs rupture to allow the wedge bodies to move into one another, ultimately causing a clamping action and self-locking of the telescoping wedge bodies. In other words, once the predetermined breaking web rupture and the wedge bodies are clamped together, the first and second metal castings are securely and reliably interconnected. The funnel shape of the wedge bodies enables a self-centering of adjoining wedge bodies so that the metal castings, despite a change in their relative length, are able to assume a predetermined position also after a crash. The self-locking action between the clamped wedge bodies prevents inadvertent separation of the metal castings. Thus, the present invention results in an adaptive crash structure that can be manufactured in its entirety through a casting process at optimum weight and optimum crash behavior to convert crash energy into deformation energy.
[0008] The adaptive crash structure according to the invention exhibits its benefits in particular when extending in a length direction of the vehicle. In this case, the deformation element also extends in length direction of the vehicle and is thus able to resist and absorb to a certain degree in particular a frontal impact force. In the event of a crash, the deformation element shortens by a predetermined length while absorbing energy at the same time and especially retaining load-bearing capability following a crash.
[0009] According to another feature of the present invention, the deformation element may be disposed at an angle to the length direction of the vehicle. Suitably, the angle ranges between 45° and 135°, e.g. 90°. As a result, the deformation element can thus be applied also in the side zones of the vehicle that are subjected at a side impact.
[0010] Examples of parameters that are relevant in addition to material selection for the energy absorption of the deformation element include angle of slope, wall thickness, dimensioning of the predetermined breaking webs, and surface roughness and surface geometry.
[0011] According to another feature of the present invention, neighboring wedge bodies may have wall portions to come into contact with confronting surfaces which are defined by angles of slope in conformity to one another and selected in such a manner that the telescoping wedge bodies are clamped with one another in a self-locking manner. The selection of the angle of slope requires a balance between reliable self-locking action and minimum length dimension of the structure. When selecting the angle of slope too great, the deformation element would lose its load-carrying capability after a crash. On the other hand, when the angle of slope is too small, although self-locking action is ensured, this is realized at the expense of a compact deformation element as its length increases.
[0012] According to another feature of the present invention, the confronting surfaces of the wall portions of the neighboring wedge bodies may be formed, at least partially, with a surface structure which deforms as a result of friction when the wedge bodies move into one another. In this way, self-locking is improved. Application of casting technology produces substantial surface roughness that plays a factor when selecting an optimum angle of slope, wall thickness, and dimensioning of the predetermined breaking webs so as to realize optimum energy absorption as a result of deformation and friction at predetermined length reduction within a predefined tolerance range. The term “surface roughness” is used in the description in a generic sense and involves not only surface roughness produced during casting but covers also additional formations such as, e.g., small ribs or webs which interlock to thereby ensure a clamping of telescoping wedge bodies. The surface may also have a geometry that produces a swirl, i.e. a rotation about the length axis of a wedge body. As a consequence of a mutual rotation, the wedge bodies are prevented from pulling apart in a rectilinear movement and thus are held securely upon one another.
[0013] To retain the load-bearing capability, the wedge bodies have to maintain their integrity in the event of a crash. Only the predetermined breaking webs are intended to rupture and their stress resistance is selected to break before a predefined maximum tensile stress and pressure stress in circumferential direction has been reached in the wedge body. The predetermined breaking webs are thus configured to reliably rupture before a material break of the wedge bodies can occur. The stress resistance of the predetermined breaking webs may be further adjusted in a way that the predetermined breaking webs rupture successively and not simultaneously. When a predetermined breaking web ruptures, the previously connected wedge bodies move into one another telescopically up to a certain depth. This, by itself, results in an adaptable energy absorption. Upon reaching a maximum penetration depth, the next predetermined breaking web ruptures, and so forth until all predetermined breaking webs break and all wedge bodies abut one another. The maximum penetration depth may also be equated to a maximum force level.
[0014] Attachment of the deformation element to the metal castings can be realized by using adapter pieces which are configured to provide a transition between the geometry of the metal casting and the geometry of the wedge body. The adapter pieces may also be connected in one piece with the wedge bodies, on one hand, and the metal castings, on the other hand, by means of a casting process.
[0015] In view of the cascading disposition of the wedge bodies and the varying load level which each wedge body has to absorb or to transmit, it may be suitable to provide the wedge bodies of different wall thicknesses. Suitably, the wall thickness of the wedge body whose predetermined breaking web ruptures first is smaller than a wall thickness of the next following one of the wedge bodies. The wall thickness of each wedge body may be kept constant in length dimension of the wedge body or may expand from a narrow end to a wider end of the funnel shape. The increase in wall thickness towards the funnel-shaped expansion is currently preferred because the inside wall region of smaller diameter is compressed while the wall region of greater diameter is pushed from inside to the outside when telescoping. Neighboring wedge bodies are so dimensioned and adjusted to one another as to realize an adjustable energy absorption during telescoping as a result of plastic material elongation of the outer wall region and concomitant compression of the inner wall region as well as friction during telescoping, without experiencing material breakage of the walls.
[0016] According to another feature of the present invention, the wedge bodies may have successively increasing outer diameter, with the wedge body having a smallest outer diameter being the leading wedge body and with the remaining wedge bodies being positioned in succession in the order of increasing outer diameter. In this way, metal castings of widely varying dimensions can be connected together. Extreme diametrical fluctuations can be compensated through use of suitable adapter pieces between the deformation element and the metal castings.
[0017] Interaction between cone angle, wall thickness, stress resistance of the predetermined breaking webs, and surface structure plays an important role for the function of the deformation element. The cross section of the wedge bodies may widely differ. Currently preferred are wedge bodies having a geometry of a hollow truncated cone because this configuration is able to ensure a self-centering upon a common center length axis of the wedge bodies. Other examples of geometries for the wedge bodies include a hollow truncated pyramid, or a hollow truncated wedge. Also conceivable are wedge bodies having at least one guide surface extending in length direction, e.g. polygonal wedge bodies, such as star-shaped wedge bodies. Within certain limits, a mutual rotation of the wedge bodies, as they move into one another, can be prevented, or, when a helical geometry is involved, promoted in a desired manner.
[0018] According to another feature of the present invention, the deformation element may be made of aluminum or aluminum alloy. Of course, other appropriate cast material may be applicable as well.
[0019] Manufacture of the adaptive crash structure according to the invention can be facilitated by providing the deformation element with at least one opening on its circumference. This eliminates the need for application of a hollow casting process. The deformation element may therefore have an open cross section of different configuration.
[0020] A deformation element according to the invention may be used in addition to its incorporation in the front vehicle area also for adaptive crash purposes when structures or chassis parts in the rear vehicle area or rear section are involved.
BRIEF DESCRIPTION OF THE DRAWING
[0021] Other features and advantages of the present invention will be more readily apparent upon reading the following description of currently preferred exemplified embodiments of the invention with reference to the accompanying drawing, in which:
[0022] FIG. 1 is a simplified schematic plan view of a adaptive crash structure according to the present invention;
[0023] FIG. 2 is a longitudinal section of one embodiment of a deformation element for incorporation in the structure of FIG. 1 ;
[0024] FIGS. 3 a - 3 e are schematic illustrations of sequential operational stages as the deformation element undergoes a telescoping movement in the event of a crash; and
[0025] FIGS. 4-6 show schematic illustration of various shapes of a wedge body.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0026] Throughout all the Figures, same or corresponding elements are generally indicated by same reference numerals. These depicted embodiments are to be understood as illustrative of the invention and not as limiting in any way. It should also be understood that the drawings are not necessarily to scale and that the embodiments are sometimes illustrated by graphic symbols, phantom lines, diagrammatic representations and fragmentary views. In certain instances, details which are not necessary for an understanding of the present invention or which render other details difficult to perceive may have been omitted.
[0027] Turning now to the drawing, and in particular to FIG. 1 , there is shown a simplified schematic plan view of an adaptive crash structure according to the present invention, generally designated by reference numeral 1 , for use in a motor vehicle. The structure 1 includes two side parts 2 which extend in travel direction of the vehicle, and two crossbars 3 a , 3 b which extend transversely to the travel direction and interconnect the side parts 2 . Each side part 2 has three regions: a first metal casting 4 for attachment of the crossbar 3 a , a deformation element 5 in prolongation of the metal casting 4 , and a second metal casting 6 for attachment of the crossbar 3 b . The metal castings 4 , 6 are shown here schematically only and should not be regarded as a limitation since their concrete configuration is not essential to this invention. A more important part of the present invention is the configuration of the deformation element 5 .
[0028] The deformation element 5 assumes the task of absorbing forces introduced in a crash and to convert them into deformation work. The illustrated arrows F indicate the force attack direction, i.e. the force F is introduced via a bumper 19 into the front metal castings 6 and the deformation elements 5 which, in turn, are supported on the adjoining metal castings 4 . In the exemplified embodiment shown in the drawing, each side part 2 of the structure 1 is completely made in one pour as metal casting. The need for jointing operations between the metal castings 4 , 6 and the deformation element 5 is eliminated.
[0029] FIG. 2 shows in greater detail a longitudinal section of one embodiment of the deformation element 5 for incorporation in the structure 1 . In the exemplified embodiment, shown here, the deformation element 5 is comprised of five funnel-shaped wedge bodies S, A, B, C, E, whereby wedge body S represents the leading (start) wedge body and wedge body E represents the trailing (or last) stoppage wedge body. For sake of clarity, the term “leading” will denote a location closest with respect to the bumper 19 , while the term “trailing” will denote a location furthest away from the bumper 19 .
[0030] The leading wedge body S is connected in one piece with an adapter piece 7 , and the trailing wedge body E is connected in one piece with an adapter piece 8 . The adapter pieces 7 , 8 have, by way of example, a tubular configuration of a diameter which conforms to the attachment diameters of the leading and trailing wedge bodies S, E, respectively. The diameter of the adapter piece 7 , connected to the leading wedge body S, is smaller than the diameter DE of the adapter piece 8 , connected to the trailing wedge body E. The adapter pieces 7 , 8 as well as the in-between wedge bodies S, A, B, C, E extend on a common length axis LA.
[0031] As shown in FIG. 2 , the wedge bodies S, A, B, C, E are defined by an outer diameter DS (only the outer diameter of the leading wedge S is labeled here by “DS”, and the outer diameter DS of the trailing wedge body E corresponds to the outer diameter DE of the adapter piece 8 ), whereby the outer diameter DS increases from the leading wedge body S in the direction of the trailing wedge body E. In addition, all wedge bodies S, A, B, C, E have conforming angles of slope W so that confronting surfaces 9 , 10 of contacting walls 11 , 12 of the wedge bodies S, A, B, C, E rest flatly upon one another and are able to effect a tight intergrip in a self-locking manner, when the wedge bodies S, A, B, C, E move into one another in a telescopic manner. This action is assisted by providing the confronting surfaces 9 , 10 of the wedge bodies S, A, B, C, E, at least partly, with a surface structure which deforms as a result of friction during telescoping of the wedge bodies S, A, B, C, E.
[0032] Each of the wedge bodies S, A, B, C, E is connected via a predetermined breaking web 13 , 14 , 15 , 16 , with the respectively next wedge body S, A, B, C, E. The predetermined breaking webs 13 , 14 , 15 , 16 are arranged in this example at the wide end of the respective funnel-shaped wedge body S, A, B, C in the direction proximal to the trailing wedge body E and project into a radial plane inwards to connect, e.g., the wall 11 of the leading wedge body S with the wall 12 of the engaging adjacent wedge body A, and so forth. In other words, adjacent wedge bodies S, A, B, C, E are connected to one another via the predetermined breaking webs 13 , 14 , 15 , 16 . The penetration depth T of a wedge body A, B, C, E into the respectively adjacent wedge body S, A, B, C is sized enough to allow connection of the wedge bodies S, A, B, C, E via the interposed predetermined breaking webs 13 , 14 , 15 , 16 and to ensure in addition a mutual guidance of the wedge bodies S, A, B, C, E, when a predetermined breaking web 13 , 14 , 15 , 16 is crushed. Thus, the penetration depth T is only insignificantly greater than twice the width of a predetermined breaking web 13 , 14 , 15 , 16 .
[0033] As further shown in FIG. 2 , each of the wedge bodies S, A, B, C, E has a wall thickness D which increases in the direction of the respectively successive wedge body A, B, C, E. In addition, the mean wall thickness of the individual wedge bodies S, A, B, C, E increases from the leading wedge body to the trailing wedge body E.
[0034] As shown in FIGS. 4 to 6 , the wedge bodies S, A, B, C, E may be configured of any suitable cross section. FIG. 4 shows by way of example a circular configuration, whereas FIG. 5 shows a star-shaped configuration, and FIG. 6 shows a polygonal, in particular a tetragonal, configuration. As indicated by way of example in FIG. 2 , the deformation element 5 may be provided with at least one opening 20 on a circumference of one of the wedge bodies S, A, B, C, E (here wedge body E).
[0035] The mode of operation of the deformation element 5 will now be described with reference to FIGS. 3 a - 3 e , showing five individual phases to illustrate the chronological sequence in the event of a crash. FIG. 3 a corresponds to the illustration of FIG. 2 and shows the initial state before a force F is introduced as a result of an impact. When a certain force level has been exceeded, as indicated in FIG. 3 b by arrow Fir the predetermined breaking web 13 between the leading wedge body S and the adjacent wedge body A is crushed so that the leading wedge body S is pushed over the adjacent wedge body A. As a result, the wedge bodies S, A are wedged together. At the same time, energy is dissipated as a consequence of the rupture of the predetermined breaking web 13 and friction between the wedge bodies S, A. As the leading wedge body S is pushed over the adjacent wedge body A, the outer wall portion 17 of the leading wedge body S expands whereas the inner wall portion 18 , which is surrounded by the outer wall portion 17 , is concomitantly compressed. The wall portions 17 , 18 are hereby pressed into one another in such a manner that the wedge bodies S, A are guided securely in relation to one another and a desired length reduction about a distance L 1 is realized. In other words, the deformation element 5 yields to a limited degree up to a certain force level.
[0036] When the applied force exceeds a higher predefined force level, as indicated by arrow F 2 in FIG. 3 c , the next predetermined breaking web 14 , which connects the wedge body A with the following wedge body B, is crushed. As a result, the deformation element 5 is shortened by the distance L 2 . Additional energy is absorbed as a result of the rupture of the predetermined breaking web 14 , and the friction between the wedge bodies A, B, and the expansion of the compressed wedge bodies A, B.
[0037] FIG. 3 d shows the state in which a still greater force F 3 is applied, resulting in a shortening of the deformation element 5 by a distance L 3 , and FIG. 3 e shows the state in which a still greater force F 4 is applied, resulting in a shortening of the deformation element 5 by a distance L 4 , while energy is increasingly absorbed. FIG. 3 e shows the maximum compression of the deformation element 5 .
[0038] An adaptive crash structure 1 according to the invention with integrated deformation element allows absorption of a certain energy amount as a consequence of deformation, friction and sequential destruction of the predetermined breaking webs 13 , 14 , 15 , 16 . The structure 1 is easy to produce by a casting process and is resilient to impact despite the relatively low ductility whereby all casting parts are solidly connected to one another at the same time.
[0039] While the invention has been illustrated and described in connection with currently preferred embodiments shown and described in detail, it is not intended to be limited to the details shown since various modifications and structural changes may be made without departing in any way from the spirit of the present invention. The embodiments were chosen and described in order to best explain the principles of the invention and practical application to thereby enable a person skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated.
[0040] What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims and includes equivalents of the elements recited therein: | An adaptive crash structure of a vehicle body or chassis of a motor vehicle includes a first metal casting and a second metal casting. A deformation element in the form of a metal casting for absorbing energy interconnects and forms with the first and second metal castings a single piece construction through a casting process. The deformation element is comprised of a plurality of funnel-shaped wedge bodies which are disposed in succession, with neighboring wedge bodies being connected through intervention of a predetermined breaking web. Each wedge body is defined by a diameter, wherein the diameters of the wedge bodies are sized to allow the wedge bodies to move telescopically into one another when a limit stress is reached and the predetermined breaking webs rupture so as to effect a tight intergrip of the telescoping wedge bodies in a self-locking manner. | 5 |
BACKGROUND OF THE INVENTION
[0001] The subject matter disclosed herein relates to gas furnaces and in particular to gas furnaces having a sealed connection between a combustion chamber and a primary heat exchanger.
[0002] Gas fired appliances, such as residential and light commercial heating furnaces for example, often arrange a combustion chamber in series with one or more heat exchangers. The heated gas from the combustion chamber flows through the heat exchanger that transfers thermal energy from the combustion gas to air passing over the heat exchanger. In general, the pressure within the heat exchanger is less than atmospheric pressure. As a result, atmospheric air may be drawn into the system resulting in a disruption of the combustion process that decreases efficiency.
[0003] The connection between the combustion chamber and the heat exchanger is one area where a seal to prevent infiltration of air is desired. This connection is typically adjacent the combustion chamber. As a result, the infiltration of air may impinge upon the flame, which disrupts the combustion process resulting in an incomplete combustion of the fuel. The heat exchanger typically has an inlet with a flange that extends from one end. A flat plate that includes sponge rubber gaskets is crimped to the flange. While this seal arrangement is suitable, the process of crimping requires additional backup tooling to prevent separation of the heat exchanger during assembly. Further, the circular/parallel inlet flange causes aggressive wear on the fabrication tooling.
[0004] Accordingly, while existing gas furnaces are suitable for their intended purposes improvements may be made in improving the coupling and sealing of the heat exchanger to a combustion chamber to minimize the impingement of air on the combustion process.
[0005] This background information is provided to reveal information believed by the applicant to be of possible relevance to the present invention. No admission is necessarily intended, nor should be construed, that any of the preceding information constitutes prior art against the present invention.
BRIEF DESCRIPTION OF THE INVENTION
[0006] According to one aspect of the invention, a heat exchanger system is provided. The heat exchanger system includes an attachment plate having at least one recess and a pair of slots extending from the at least one recess. A heat exchanger member having an inlet, the inlet having a first flange coupled within the at least one recess and a pair second flanges disposed within the pair of slots.
[0007] According to another aspect of the invention, a heat exchanger system for a gas appliance having a combustion chamber is provided. The heat exchanger system includes an attachment plate coupled to the combustion chamber, the attachment plate having at least one recess, a first slot extending from one side of the at least one recess and a second slot extending from the at least one recess opposite the first slot. A heat exchanger member having an inlet fluidly is coupled to receive a combustion gas from the combustion chamber. The inlet has a first flange arranged about an opening and fixedly disposed in the at least one recess, and a pair of second flanges arranged adjacent and substantially perpendicular to the first flange. The pair of second flanges is disposed in the first slot and the second slot.
[0008] According to yet another aspect of the invention, a method of assembling a heat exchanger system to a combustion chamber is provided. The method includes the step of providing an attachment plate having at least one recess and a pair of slots extending from the at least one recess. A heat exchanger member is provided having an inlet with a first flange disposed about an opening and a pair of second flanges adjacent the first flange. The first flange is disposed in the at least one recess. The pair of second flanges is disposed in the pair of slots. The heat exchanger member is coupled to the attachment plate in the at least one recess. The inlet is supported with the at least one recess when the heat exchanger member is coupled to the attachment plate.
[0009] These and other advantages and features will become more apparent from the following description taken in conjunction with the drawings.
BRIEF DESCRIPTION OF THE DRAWING
[0010] The subject matter, which is regarded as the invention, is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features, and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which:
[0011] FIG. 1 is a perspective cut away illustration of a gas furnace in accordance with an embodiment of the invention;
[0012] FIG. 2 is a schematic illustration of a combustion chamber and heat exchanger arrangement in accordance with an embodiment of the invention;
[0013] FIG. 3 is a perspective illustration of an attachment plate for use with the gas furnace of FIG. 1 ;
[0014] FIG. 4 is a perspective illustration of another embodiment attachment plate for use with the gas furnace of FIG. 1 ;
[0015] FIG. 5 is a perspective view illustration of a primary heat exchanger for use with the gas furnace of FIG. 1 ;
[0016] FIGS. 6-7 are perspective view illustrations of the primary heat exchanger of FIG. 5 being assembled to the attachment plate of FIG. 3 ;
[0017] FIG. 8 is a perspective view illustration of the attachment plate of FIG. 3 crimped onto the primary heat exchanger of FIG. 5 ; and,
[0018] FIG. 9 is a partial cross sectional view of the attachment plate of FIG. 4 crimped onto the primary heat exchanger of FIG. 5 .
[0019] The detailed description explains embodiments of the invention, together with advantages and features, by way of example with reference to the drawings.
DETAILED DESCRIPTION OF THE INVENTION
[0020] FIG. 1 is a perspective cutaway view of furnace 10 . Furnace 10 includes burner assembly 12 , combustion chamber 14 , combustion air pipe 16 , gas valve 18 , primary heat exchanger 20 , condensing heat exchanger 24 , condensate collector box 26 , exhaust vent pipe 28 , induced draft blower 30 , inducer motor 32 , thermostat 34 , low pressure switch 42 , high pressure switch 44 , and furnace control 50 .
[0021] Burner assembly 12 is located within combustion chamber 14 and is supplied with air via combustion air pipe 16 . Fuel gas is supplied to burner assembly 12 through gas valve 18 , which may be a solenoid-operated gas valve, and is ignited by an igniter assembly (not shown). The gases produced by combustion within combustion chamber 14 flow through a heat exchanger assembly, which includes primary or non-condensing heat exchanger 20 , secondary or condensing heat exchanger 24 , and condensate collector box 26 . It should be appreciated that while only a single heat exchanger 20 is illustrated, the furnace 10 may have multiple heat exchangers 20 coupled in parallel to the combustion chamber 14 . The gases are then vented to the atmosphere by inducer motor 32 through exhaust vent pipe 28 . The flow of these gases, herein called combustion gases, is maintained by induced draft blower 30 , which is driven by inducer motor 32 . Inducer motor 32 is driven in response to speed control signals that are generated by a furnace control circuit located within furnace control 50 , in response to the states of low pressure switch 42 and high pressure switch 44 , and in response to call-for-heat signals received from thermostat 34 in the space to be heated.
[0022] Air from the space to be heated is drawn into furnace 10 by blower 52 , which is driven by blower motor 54 in response to speed control signals that are generated by furnace control 50 . The discharge air from the blower 52 , herein called circulating air, passes over condensing heat exchanger 24 and primary heat exchanger 20 in a counter-flow relationship to the flow of combustion air, before being directed to the space to be heated through a duct system (not shown).
[0023] It should be appreciated that it is desirable to provide an adequate seal between the combustion chamber 14 and the primary heat exchanger 20 . Since the pressure within the primary heat exchanger 20 is lower than atmospheric pressure (ΔP˜0.2-0.3 inches of water, 49.8-74.7 Pascal) air will tend to be drawn into the heat exchanger 20 and combustion chamber 14 disrupting the combustion process. Referring to FIGS. 2-3 , in one embodiment the primary heat exchanger 20 is coupled to the combustion chamber 14 by an attachment plate 36 . In the exemplary embodiment, attachment plate 36 is formed from a metal sheet material, such as steel or aluminum for example. The sheet is formed with one or more embossed portions or recesses 38 having an opening 40 substantially centered therein as shown in FIG. 3 . A flange 48 extends from the opening 40 within the recess 38 to form a groove 56 . Extending from each recess are a pair of slots 46 that are arranged substantially 180 degrees apart. The slots 46 intersect and extend between the groove 56 and the edge of the attachment plate 36 . As will be discussed in more detail herein, the recess 38 , flange 48 , groove 56 and slots 46 are sized to receive and cooperate with an inlet opening flange on the primary heat exchanger 20 . Further, the attachment plate 36 may include multiple recesses 38 to allow multiple primary heat exchangers 20 to be coupled in parallel to the combustion chamber 14 .
[0024] The attachment plate 36 may also include a second plurality of recesses 58 disposed about the periphery. The recesses 58 include a hole 60 that is formed in the bottom of the recess 58 . The holes 60 may be sized to receive a fastener (not shown) that couples the attachment plate 36 to the combustion chamber 14 . In some embodiments, a gasket (not shown) is disposed between the attachment plate 36 and the combustion chamber 14 . The recesses 38 , 58 provide additional advantages in compressing or pinching the gasket material as the attachment plate is coupled to the combustion chamber 14 . It should be appreciated that while the embodiments described herein refer to a separate attachment plate 36 , in other embodiment the recesses 38 , opening 40 , flange 48 and slots 46 may be integrated into the housing of the combustion chamber 14 . It should be appreciated that the recesses 58 allow the fasteners to be tightened to the combustion chamber 14 when the primary heat exchanger 20 is installed.
[0025] Another embodiment of the attachment plate 36 is illustrated in FIG. 4 . In this embodiment, opening 40 has a scalloped flange 62 that includes a plurality of projections 64 . In one embodiment, the projections 64 are defined by a smooth curved profile that contiguously extends from a trough portion to a peak portion as the flange 62 extends about the opening 40 . In one embodiment, the plurality of projections 64 includes a first projection 66 and a second projection 68 are arranged on opposite sides of the flange 62 with each projection 66 , 68 centered on one of the slots 46 . As will be discussed in more detail herein, the projections 66 , 68 include additional material that provides advantages in reducing or eliminating the infiltration of atmospheric air into the combustion chamber 14 .
[0026] The primary heat exchanger 20 is formed in two halves 70 , 72 from a sheet metal material, such as steel or aluminum for example as shown in FIG. 2 and FIG. 5 . The two halves 70 , 72 are joined together by a suitable process such as fasteners, crimping, welding, brazing or a combination thereof for example. The primary heat exchanger 20 includes an inlet 74 that is fluidly coupled to receive heated gases from the combustion chamber 14 . A serpentine path 76 extends through the heat exchanger 20 providing a surface area for the transfer of heat from the combustion chamber gases to air flowing over the primary heat exchanger 20 . The gases leave primary heat exchanger 20 via an outlet 78 that is fluidly coupled to the condensing heat exchanger 24 .
[0027] In the exemplary embodiment, the inlet 74 has a first flange 80 arranged substantially perpendicular to the flow of combustion gases. The first flange 80 further defines the outer diameter of the inlet opening 82 . A pair of second flanges 84 extends away from the inlet 70 and provides an area for the crimping of the two heat exchanger halves 70 , 72 . The outer surface of the inlet 70 and the first flange 80 are sized to fit within the groove 56 such that the flange 48 of the attachment plate 36 fits within and extends into the opening 82 . It should be appreciated that where the two halves 70 , 72 meet, a small gap 86 may exist due to the curvature of the material in forming the second flanges 84 .
[0028] Referring now to FIG. 6-FIG . 8 , the assembly of the primary heat exchanger 20 with the attachment plate 36 will be described. The primary heat exchanger 20 is arranged such that the inlet 74 is inserted into the groove 56 with the second flanges 84 aligned with and disposed in the slots 46 . With the inlet 74 and attachment plate 36 so arranged, an operator inserts a crimping tool 88 or fixture into the opening 40 . When actuated, the tool 86 bends the attachment plate flange 48 over the inlet first flange 80 crimping the flanges 48 , 80 and forming a seal without an intermediary gasket or seal member. The recess 38 provides support for the heat exchanger halves 70 , 72 while the crimp is being formed. This support by the recess 38 provides advantages in preventing the heat exchanger halves 70 , 72 from separating as a result of the radial crimping force applied to the flange 48 . It should be appreciated that by preventing separation of the heat exchanger halves 70 , 72 , an increase in the gap 86 during the crimping process may be prevented or minimized. In one embodiment, the operator may place a sealant, such as a silicone material or a sponge rubber for example, into the groove 56 and slots 46 prior to inserting the primary heat exchanger 20 into the grooves 56 and slots 46 . It should be appreciated that the crimping of the attachment plate 36 to the primary heat exchanger 20 provides advantages in improving the seal and also assists in preventing the separation of the heat exchanger halves 70 , 72 during the crimping operation.
[0029] In embodiments where the attachment plate 36 includes the scalloped flange 62 , additional advantages are gained in increasing the amount of material that overlaps the gap 86 . As shown in FIG. 9 , the projections 66 , 68 extend up an inner wall 90 of the inlet 74 . In this arrangement, the projections 66 , 68 over lap the gap 86 along a portion of the inner wall 90 in addition to the first flange 80 . In the event that air does infiltrate the gap 86 , the air will be directed with the flow of the combustion gases since the projections 66 , 68 extend parallel to the wall 90 . By flowing the air in a direction parallel to the combustion gases there would be no or minimal impingement of infiltration air on the combustion flames, and thus not affecting combustion efficiency or reliability.
[0030] As disclosed, some embodiments of the invention may include some of the following advantages: improving the seal between the combustion chamber and the heat exchanger inlet; not reducing the efficiency of the combustion process in the event of infiltration; improving the support of the heat exchanger during the assembly process; the directing infiltrating air away from the combustion chamber.
[0031] While the invention has been described in detail in connection with only a limited number of embodiments, it should be readily understood that the invention is not limited to such disclosed embodiments. Rather, the invention can be modified to incorporate any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the invention. Additionally, while various embodiments of the invention have been described, it is to be understood that aspects of the invention may include only some of the described embodiments. Accordingly, the invention is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims. | A heat exchanger system and a method of assembly is provided for a gas appliance such as a furnace. The heat exchanger system includes an attachment plate having at least one recess sized to receive an inlet of a heat exchanger. The heat exchanger has a first flange disposed at the inlet that is positioned in the recess. A second flange in the attachment plate recess is crimped onto the inlet flange to couple the heat exchanger to the attachment plate. The attachment plate may also include a pair of slots that extend from the recess that are sized to receive a pair of third flanges on the heat exchanger. | 5 |
This application is a continuation-in part application of application U.S. Ser. No. 08/188,220, entitled “Method of Making Superconducting Wind-And-React Coils”, filed on Jan. 28, 1994 and now issued as U.S. Pat. No. 5,531,015.
FIELD OF THE INVENTION
This invention relates to cabled superconducting oxide conductors and to a method for their manufacturing. The present invention further relates to a method for healing defects introduced into the oxide superconductor composite during cabling and thereby improving superconducting properties.
BACKGROUND OF THE INVENTION
Since the discovery of oxide superconducting materials with transition temperatures above about 20 Kelvin the possibility of using them to obtain greater efficiency in electrical and magnetic applications has attracted considerable interest. However, to be practical outside the laboratory, most electrical and magnetic applications require flexible cabled lengths of conductor manufacturable with high packing factors which can be manufactured at reasonable cost and with high engineering current-carrying capacity. High packing factor forms are needed because limited space constraints and high overall current requirements are major design issues. Conductors which are flexibly cabled, that is, composed of twisted, helically wound, braided or otherwise transposed bundles of electrically, and sometimes mechanically, isolated conductor strands, are desired in many applications, including coils, rotating machinery and long length cables. In comparison to monolithic conductors of comparable composition and cross-section, cabled forms which are made from a number of isolated conductors strands will have much higher flexibility. Substantially mechanically isolated cable strands have some ability to move within the cable, although some degree of mechanical locking of the strands is desired for stability and robustness of the conductor to stay together during handling and winding. Electrical isolation of the cable strands is preferred but not required. In low temperature superconducting conductors, cables which are made from a number of substantially electrically isolated and transposed conductor strands have been shown to have greatly reduced AC losses in comparison to monolithic conductors. See “ Superconducting Magnets” by Martin Wilson (1983,1990), pp 197, 307-309. It has been proposed that the same relation will hold for high temperature superconductors. Flexibility increases in proportion to the ratio between the cable cross-section and the strand cross-section. AC losses are believed to decrease in relation to cable cross-section, strand cross-section and twist pitch. Thus, the greater the number of strands in a cable of given dimension, the more pronounced these advantages will be.
However, it has not been considered feasible to form oxide superconductors in high winding density, tightly transposed configurations because of the physical limitations of the material. Superconducting oxides have complex, brittle, ceramic-like structures which cannot by themselves be drawn into wires or similar forms using conventional metal-processing methods and which do not possess the necessary mechanical properties to withstand cabling in continuous long lengths. Consequently, the more useful forms of high temperature superconducting conductors usually are composite structures in which the superconducting oxides are supported by a matrix material, typically a noble metal, which adds mechanical robustness to the composite.
Even in composite forms, the geometries in which high-performance superconducting oxide articles may be successfully fabricated are constrained by the relative brittleness of the composite, by the electrical anisotropy characteristic of the oxide superconductor, and by the necessity of “texturing” the oxide material to achieve adequate critical current density. Unlike other known conductors, the current-carrying capacity of a superconducting oxide composite depends significantly on the degree of crystallographic alignment and intergrain bonding of the oxide grains, together known as “texturing”, induced during the composite manufacturing operation.
Known processing methods for obtaining textured oxide superconductor composite articles include an iterative process of alternating anneal and deformation steps. The anneal is used to promote reaction-induced texture (RIT) of the oxide superconductor in which the anisotropic growth of the superconducting grains is enhanced. Each deformation provides an incremental improvement in the orientation of the oxide grains (deformation-induced texturing or DIT).
The texture derived from a particular deformation technique will depend on how closely the applied strain vectors correspond to the slip planes in the superconducting oxide. Thus, superconducting oxides such as the BSCCO family, which have a micaceous structure characterized by highly anisotropic preferred cleavage planes and slip systems, possess a highly anisotropic current-carrying capacity. Such superconducting oxides are known to be most effectively DIT textured by non-axisymmetric techniques such as pressing and rolling, which create highly aspected (greater than about 5:1) forms. Other methods of texturing BSCCO 2223 have been described in U.S. Ser. No. 08/302,601, filed Sep. 8, 1994 entitled “Torsional Texturing of Superconducting Oxide Composite Articles”, which describes a torsional texturing technique; U.S. Ser. No. 08/041,822 filed Apr. 1, 1993, entitled “Improved Processing for Oxide Superconductors” now issued as U.S. Pat. No. 5,635,456; and U.S. Ser. No. 08/198,912 filed Feb. 17, 1994, entitled “Improved Processing of Oxide Superconductors” which is now issued as U.S. Pat. No. 5,635,456 which describes an RIT technique based on partial melting. These techniques have been observed to provide the greatest improvement in the Jc's of BSCCO 2223 samples when used in combination with a highly non-axisymmetric DIT technique, such as rolling.
Although superconducting oxide composite articles may be textured by various methods, including magnetic alignment, longitudinal deformation (DIT) or heat treatment (RIT), not all texturing methods are equally applicable to, or effective for, all superconducting oxides. For example, known techniques for texturing the two-layer and three-layer phases of the bismuth-strontium-calcium-copper-oxide family of superconductors (Bi 2 Sr 2 Ca 1 Cu 2 O x and Bi 2 Sr 2 Ca 2 Cu 3 O x , also known as BSCCO 2212 and BSCCO 2223, respectively) are described in Tenbrink et al., “Development of Technical High-T c Superconductor Wires and Tapes”, Paper MF-1, Applied Superconductivity Conference, Chicago(Aug. 23-28, 1992), H. B. Liu and J. B. Vander Sande, submitted to Physica C, (1995), and Motowidlo et al., “Mechanical and Electrical Properties of BSCCO Multifilament Tape Conductors”, paper presented at Materials research Society Meeting, Apr. 12-15, 1993. Micaceous oxides such as the BSCCO family which demonstrate high current carrying capacity in the absence of biaxial texture have been considered especially promising for electrical applications because they can be textured by techniques which are readily scalable to long-length manufacturing.
Liquid phases in co-existence with solid oxide phases have been used in processing of oxide superconductors. One type of partial melting, known as peritectic decomposition, takes advantage of liquid phases which form at peritectic points of the phase diagram containing the oxide superconductor. During peritectic decomposition, the oxide superconductor remains a solid until the peritectic temperature is reached, at which point the oxide superconductor decomposes into a liquid phase and a new solid phase. The peritectic decompositions of Bi 2 Sr 2 CaCu 2 O 8+x , (BSCCO 2212, where 0≦x≦1.5), into an alkaline earth oxide and a liquid phase and of YBa 2 Cu 3 O 7−δ (YBCO 123, where 0≦δ≦1.0) into Y 2 BaCuO 5 and a liquid phase are well known. Kase et al. in IEEE Trans. Mag. 27(2), 1254 (1991) report obtaining highly textured BSCCO 2212 by slowly cooling through the peritectic point, a RIT technique because BSCCO 2212 totally melts and reforms during melt textured growth, any texturing induced by deformation prior to the melting will not influence the final structure.
However, BSCCO 2223 cannot be effectively textured by the melt-textured growth technique. Instead of peritectic melting, BSCCO 2223 exhibits irreversible melting in that solid 2223 does not form directly from a liquid of 2223 composition. RIT techniques applicable to BSCCO 2223 rely on some type of partial melting, such as eutectic melting, solid solution melting or formation of non-equilibrium liquids, in which the oxide superconductor coexists with a liquid phase rather than being totally decomposed.
Partial melting of (Bi,Pb) 2 Sr 2 Ca 2 Cu 3 O 10+x , ((Bi,Pb)SCCO 2223, where 0≦x≦1.5 ) and (Bi) 2 Sr 2 Ca 1 Cu 2 O 10+x ((Bi)SCCO 2223, where 0≦x≦1.5 ) at temperatures above 870° C. in air has been reported; see, for example, Kobayashi et al. Jap. J. Appl. Phys. 28, L722-L744 (1989), Hatano et al. Ibid. 27(11), L2055 (Nov. 1988), Luo et al. Appl. Super. 1, 101-107, (1993), Aota et al. Jap. J. Appl. Phys. 28, L2196-L2199 (1989) and Luo et al. J Appl. Phys. 72, 2385-2389 (1992). The exact mechanism of partial melting of BSCCO-2223 has not been definitively established.
Such partial melting techniques are inherently more dependent on the geometry of the initial phase than melt-textured growth, and texturing induced by deformation prior to the partial melting will have a significant impact on the texturing of the final product. In short, for superconducting oxides with irreversible melting characteristics, such as BSCCO 2223, superior texturing and current-carrying capacity are most obtainable in highly aspected forms such as tapes.
Unfortunately, highly aspected superconducting oxide tapes are particularly difficult to cable. All superconducting oxide composites are brittle by the standards of conventional conductors. It is well known that exerting any bend strain in excess of a critical strain which is determined by the composition and geometry of the composite (and which is typically on the order of 0.1-1%) will severely degrade its electrical and mechanical properties. Strands which are round in cross-section can be bent in any plane and the bend strain will be the same, but the strain on a highly aspected strand will depend on the bend direction, with highest strains when the bend is in the plane of the longer cross-sectional dimension. The effect on strand performance can be considerable, since the bend strain increases proportionally to the thickness of the bent material and the critical current drops asymptotically at bend strains in excess of the critical strain.
Since the lowest coupling losses are predicted to come from fully transposed cables, limitations on the direction in which the strands can be cabled also limits the potential usefulness of the cabled conductor. Unfortunately, some forms of transposition makes it inevitable that some portion of the cabled conductor will not be oriented in the preferred direction. Thus, an important consideration in fabricating high performance oxide superconducting conductors is maximizing the portions which do have the desired orientations. It is thus desirable to main a common orientation for all strands in the cable. In rigid cabling techniques the oxide superconducting strands rotate around cable axis resulting in strands of various orientations. In planetary cabling, the oxide superconductor strands do not rotate and transposition only results in slight misorientation.
The difficulties of handling superconducting oxide strands appear even more pronounced when the need for a low cost, scalable cable manufacturing process is considered. There are a number of well-known cabling techniques, such as Rutherford cabling, braiding, and other forms of Litz cabling, for transposing low aspect ratio strands of conventional conductor material on automated machinery, which rely on gradual radial bending of the conductor strands, but to make high packing factor cables on these machines requires bending strains in excess of those tolerated by conventional oxide superconductor strands. The problem is even worse for aspected forms. The best-known automatic technique for cabling conventional highly aspected conductors requires sharp bends in the strand at regular intervals and so, not surprisingly, has never been demonstrated to be practicable for oxide superconducting composites.
SUMMARY OF THE INVENTION
These and other objects of the invention are obtained by subjecting an oxide superconductor cable to one or more two step heat treatments, after cabling or deformation, or both, of the article. The two step heat treatment includes (a) heating the cabled article at a temperature sufficient to partially melt the cabled article, such that a liquid phase co-exists with the desired oxide superconductor phase; and (b) cooling the cabled article to a temperature sufficient to transform the liquid phase into the desired oxide superconductor, with no deformation or cabling occurring after the final heat treatment. The deformation or cabling operations are those which introduce strains of about at least 5-10% and which introduce defects perpendicular to the direction of current flow resulting in significant loss of superconducting performance as measured by critical current. Strain is defined with respect to the oxide superconductor cable itself, as opposed to strain of the individual oxide strands or oxide filaments.
In another aspect of the invention, an oxide superconductor cable is prepared by exposing an oxide superconductor cable to a two step heat treatment and thereafter texturing the oxide superconductor cable. The heat treatment comprises the steps of (a) heating the cable to and maintaining the cable at a first temperature sufficient to partially melt the cable, such that a liquid phase co-exists with the desired superconducting oxide phase; and (b) cooling the cable to and maintaining the cable at a second temperature sufficient to substantially transform the liquid phase into the desired oxide superconductor. The oxide superconductor cable is then textured. The texturing process may be selected such that no further deformations are introduced into the cable. Suitable texturing processes include reaction induced texturing (RIT) and magnetic field induced grain alignment, discussed above. Alternatively, the texture operation may cause defects, i.e., deformation induced texturing (DIT), in which case, it may be desirable to perform a subsequent two step heat treatment, as described in steps (a) and (b), above.
In another aspect of the present invention, an oxide superconductor cable may be prepared by texturing an oxide superconductor cable and thereafter exposing the textured oxide superconductor cable to a two step heat treatment of the invention. The texturing process may be selected such that no further deformations are introduced into the cable. Alternatively, the texture operation may cause defects, i.e., deformation induced texturing (DIT).
In another aspect of the invention, an oxide superconductor cable containing a desired oxide superconductor phase is exposed to a one or more two step heat treatments after deformation or cabling, or both, of the oxide superconducting cable which includes (a) forming a liquid phase in the oxide superconducting cable such that the liquid phase co-exists with the desired oxide superconductor solid phase; and then (b) transforming the liquid phase into the desired oxide superconductor, with no deformation or cabling occurring after the final heat treatment. Cabling and deformation after final heat treatment referred to are those which introduce strains of about at least 5-10% and which introduce defects perpendicular to the direction of current flow resulting in significant loss of superconducting performance as measured by critical current. Strain is defined with respect to the oxide superconductor cable itself, as opposed to stain of the individual oxide strands or oxide filaments.
In preferred embodiments, the liquid phase wets surfaces of defects contained within the oxide superconductor cable strands. The defects are healed upon transformation of the liquid to the desired oxide superconductor. The partial melting of step (a) and the transformation of step (b) are effected by selection of appropriate thermodynamic state variables, for example, temperature, P O2 , P total and total composition. In principle, deformation or cabling may occur during the final heat treatment up to immediately prior to the completion of step (a), providing that the liquid phase is available for a period of time sufficient to wet defect surfaces.
By “cable”, as that term is used herein, it is meant an assemblage of a number of individual strands in close proximity along their length in a periodic arrangement by techniques including transposing, interweaving, twisting, braiding, helically winding, and the like, of the strands. Each strand of the cable may be substantially electrically isolated, and the cable may be flexible.
By “strand”, as that term is used herein, it is meant the individual lengths of oxide superconductor which are used to weave, to transpose or otherwise form the oxide superconductor cable. The strands may be rounded or may have a flattened, aspected cross-sectional geometry because of the deformation processes used to DIT texture. The strands themselves may be composed of one or multiple filaments of oxide superconductor supported within or on a malleable, conductive matrix, preferably a noble metal, or may themselves be cables.
By “two step heat treatment”, as that term is used herein, is meant a heat treatment for healing defects and forming an oxide superconductor. By “final two-step heat treatment”, as that term is used herein, it is meant a heat treatment for forming an oxide superconductor after which no further deformation or cabling occurs. However, heat treatments for purposes other than those stated herein, such as, for example, oxygenation of the oxide superconductor, are possible.
By “partial melt”, as that term is used herein, it is meant the oxide superconductor article is only partially melted, and that the desired oxide superconductor is present during melting.
By “deformation” as that term is used herein, it is meant a process which causes a change in the cross-sectional shape of the article, without loss of mass.
By “oxide superconductor precursor”, as that term is used herein, it is meant any material that can be converted to an oxide superconductor upon application of a suitable heat treatment. Suitable precursor materials include but are not limited to metal salts, simple metal oxides, complex mixed metal oxides and intermediate oxide superconductors to the desired oxide superconductor.
By “desired oxide superconductor”, as that term is used herein, it is meant the oxide superconductor which it is desired to ultimately prepare. An oxide superconductor is typically the “desired” oxide superconductor because of superior electrical properties, such as high T c and/or J c The desired oxide superconductor is typically a high T c member of a particular oxide superconductor family, i.e., BSCCO 2223, YBCO 123, TBCCO 1212 and TBCCO 1223.
By “intermediate oxide superconductor”, as that term is used herein, it is meant an oxide superconductor which is capable of being converted into a desired oxide superconductor. However, an intermediate oxide superconductor may have desirable processing properties, which warrants its formation initially before final conversion into the desired oxide superconductor. The formation of an “intermediate oxide superconductor” may be desired, particularly during anneal/deformation iterations, where the intermediate oxides are more amenable to texturing than the desired oxide superconductor.
In preferred embodiments, the intermediate oxide superconductor is BSCCO 2212 or (Bi,Pb)SCCO 2212 because it is readily textured by the deformation/anneal iterations. The intermediate oxide superconductor is then converted to a desired oxide superconducting phase, typically BSCCO 2223 or (Bi,Pb)SCCO 2223. The partial melting of step (a) may be carried out at a temperature in the range of 820-835° C. at 0.075 atm O 2 . The transformation of the liquid in step (b) may be carried out at a temperature in the range of 790-820° C. at 0.075 atm O 2 . In other preferred embodiments, the desired oxide superconductor, may be YBCO 123, Y 2 Ba 4 Cu 7 O 14−δ (YBCO 247), (Tl,Pb) 1 Ba 2 Ca 1 Cu 2 O 6.0±y (TBCCO 1212) or (Tl,Pb) 1 Ba 2 Ca 2 Cu 3 O 8.0±y (TBCCO 1223), where 0≦δ≦1.0 and y ranges up to 0.5. The stated stoichiometries are all approximate and intentional or unintentional variations in composition are contemplated within the scope of the invention.
In other preferred embodiments, the liquid phase is formed in the range of 0.1-30 vol %. In yet other preferred embodiments, the anneal of the first and second anneal/deformation iterations partially melts the oxide superconductor cable.
In yet another aspect of the invention, an oxide superconductor cable is exposed to one or more two step heat treatments after a deformation or cabling step, which includes (a) heating the cable at a temperature substantially in the range of 810-860° C. for a period of time substantially in the range of 0.1 to 300 hours at a P O2 substantially in the range of 0.001-1.0 atm; and (b) cooling the cable to a temperature substantially in the range of 780-845° C. for a period of time substantially in the range of 1 to 300 hours at a P O2 substantially in the range of 0.001-1.0 atm, with no deformation or cabling occurring after the final heat treatment.
In yet another aspect of the present invention, an oxide superconductor cable containing a desired oxide superconductor phase is exposed to a final heat treatment after a deformation or cabling step, which includes (a) subjecting the cable to an oxygen partial pressure sufficient to partially melt the oxide superconducting article, such that a liquid phase co-exists with the desired oxide superconductor; and (b) raising to an oxygen partial pressure sufficient to transform the liquid phase into the desired oxide superconductor.
Thus, a highly textured cabled conductor with improved AC loss characteristics containing a superconducting oxide with irreversible melting characteristics such as BSCCO 2223, and a process for manufacturing it is provided. A transposed cabled conductor containing superconducting oxide strands in highly aspected forms and a method for manufacturing it is also provided. The novel cabled conductor manufacturing process of the invention allows a superconducting oxide composite to be used with conventional high-speed cabling equipment. The method improves superconducting performance of oxide superconductor cables by healing cracks and defects formed during cabling of oxide superconductors strands. Cables having a critical current density of about 10,000 A/cm 2 at 77K, self field, have been prepared in accordance with the method of the invention.
A feature of the invention is a two-step heat treatment which introduces a small amount of a liquid phase co-existing with the oxide superconductor phase, and then transforms the liquid back into the oxide superconductor phase.
An advantage of the invention is the production of highly defect-free oxide superconductor cables which exhibit superior critical current densities.
BRIEF DESCRIPTION OF THE DRAWING
The invention is described with reference to the Drawing, which is provided for the purpose of illustration only and is in no way limiting of the invention, and in which:
FIG. 1 is a processing profile of the final heat treatment of the invention;
FIG. 2 is a processing profile used to obtain a textured oxide superconductor cable according to the method of the invention;
FIG. 3 is a schematic diagram illustrating processes of the present invention;
FIG. 4 is a schematic illustration of a cabling operation according to the invention;
FIG. 5 is a power vs. current for a cable of the present invention determined at a variety of magnetic field strengths;
FIG. 6 is a V-I plot (electric field vs. current) for a cable of the present invention determined at a variety of magnetic field strengths; and
FIG. 7 is a V-I plot (electric field vs. current) at 77K, self field, for a cable prepared without the method of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention is directed to a highly textured oxide superconductor cable having improved AC loss characteristics, as compared to a monolith conductor. The oxide superconductor used in the cable possesses irreversible melting characteristics which lends itself to the improved texturing and critical current density observed in the invention.
The present invention also is a method for improving the critical current density of oxide superconductor cables by healing defects, such as micro- and macrocracks and bending strain defects, incurred upon DIT deformation, cabling, or both, of the individual oxide superconductor composite strands. The present invention calls for a one or more two-step treatments after deformation, cabling, or both of the oxide superconductor cable, in which (a) a liquid phase is formed such that the liquid phase co-exists with the desired oxide superconductor; and (b) the liquid phase is then transformed into the desired oxide superconductor without any intermediate deformation. The methods of the invention can be used to heal defects in any oxide superconductor or superconducting composite cable which result from DIT processing and/or cabling operations.
The two step heat treatment operates in the following manner to heal defects. The liquid phase is formed upon partial melting of the oxide superconductor cable. During partial melting of the cable, non-superconducting materials and intermediate oxide phases may be present with the desired oxide superconductor phase. During the partial melting step of the invention the desired oxide superconductor, the non-superconducting materials, oxide superconducting precursors, the desired oxide superconductor or a mixture of these components may melt to form the liquid phase. The above process, which required that liquid co-exist with the desired oxide superconductor phase, is distinguished from those which involve the peritecitic decomposition of the oxide superconductor, such as described by Kase et al., in which the desired oxide superconductor decomposes during the melting process.
The type of cabling styles which are contemplated for use in this process include, but are in no way limited to, Roebel cabling, Rutherford cabling, braiding and other forms of Litz cabling. Rigid or planetary forms of any of these may be used. Litz cable has complete transposition of strands. Roebel, Rutherford and braids are special types of Litz cables. Some cable types, such as a six around one configuration do not have complete transposition, but may also be satisfactory. Suitable strand texturing and cabling techniques are set forth in U.S. application Ser. No. 08/554,814 entitled “Cabled Conductors Containing Anisotropic Superconducting Compounds and Method for Making Them”, filed on even date herewith, in U.S. application Ser. No. 08/554,737, now abandoned entitled “Low Resistance Cabled Conductors Comprising Superconducting Ceramics” filed on even date herewith, and in U.S. application Ser. No. 08/554,693, now U.S. Pat. No. 5,885,938 entitled “Low Aspect Ratio Superconductor Wire” filed on even date herewith.
The method of the invention is particularly useful for oxide superconductor articles which possess defects perpendicular to the direction of current flow. In such instance, the defects disrupt the percolative pathway for current flow. It is expected therefore, that healing of such defects will have a marked effect on current carrying ability.
FIG. 1 shows a processing profile of the two-step heat treatment of the invention. A dashed line 10 indicates a processing point at which a liquid phase is formed for a given set of processing conditions, e.g., T, P O2 , P total and/or oxide composition.
In the oxide superconductors and superconducting composites disclosed herein, processing conditions for obtaining the requisite liquid and solid oxide phases are well established and the relationship between temperature, oxygen partial pressure and total pressure is reasonably well understood. For further information on the phase diagrams for YBCO, BSCCO and the thallium-based systems, the interested reader is directed to “Phase Diagrams for High T, Superconductors”, John D. Whitler and Robert S. Roth, Ed.; American Ceramic Society, Westerville, Ohio.
Presence of a liquid phase can also be determined experimentally by use of such conventional techniques as differential thermal analysis (DTA). In DTA, exothermic and endothermic reactions as a function of temperature can be identified and attributed to various thermodynamic and chemical processes. It is possible to identify endothermic processes corresponding to partial melting, i.e., liquid phase formation.
It is desired that only a small amount of liquid be formed during partial melting. The reason for this is that, in preferred embodiments of the invention, at the time that the two-step heat treatment is applied, the article may already possess substantial texture. Complete or significant liquid formation at this point would result in loss of texture. Volume percent of the liquid phase is typically in the range of 0.1 to 30.
The oxide superconductor strands are cabled at a point 11 a before a two-step heat treatment, at which time bending strain may introduce defects, such as microcracks, into the cabled article. The oxide superconductor strands are typically deformed at a point 11 before a two-step heat treatment, at which time defects such as microcracks may be introduced into the article. Suitable deformation can include swaging, extruding, drawing, pressing, hot and cold isostatic pressing, rolling, and forging of wires, tapes and a variety of shaped articles. However, in some embodiments of the invention, the strands may be textured before or after cabling by an alternative texturing method which does not independently introduce defects into the cabled article. As will be seen in a discussion below, cabling and deformation or other texturing steps may be performed at different stages in the process with respect to each other and with respect to one or more of the two-step heat treatments, and such variations are within the scope of the invention. Conventional cabling machines used to cable conventional current carrying wires may be used. By way of example only, these may include Rutherford cabling, braiding, Roebel cabling, and other forms of Litz cabling machines. A Litz cable is any cable with transposed, insulated strands; however, an uninsulated strand may also be cabled. These will not retain mechanical or electrical isolation but may be useful for DC applications.
Referring again to FIG. 1, the processing conditions are adjusted to bring the cable to point 12 where the article is partially melted and a liquid phase co-exists with the desired oxide superconductor phase. The cable is held at point 12 for a period of time during which the defect surfaces contained within the oxide superconductor are wet by the newly-formed liquid. In the case of BSCCO-2223, a temperature of 820-835° C. at 0.075 atm O 2 for 0.1-300 hours and preferably 12-300, and more preferably 50-200 hours is sufficient.
The processing parameters are then adjusted to bring the oxide superconductor cable to point 13 where the liquid phase is consumed and the desired oxide superconductor phase is formed from the melt. In the case of BSCCO-2223, a temperature of 820-790° C. at 0.075 atm O 2 for 1 to 300 hours is sufficient. The processing temperature will vary dependent upon the oxygen pressure. Additionally, variations in the chemical composition of the article will also affect selection of temperature and pressure. In particular, it has been noted that addition of silver to the oxide composition lowers the temperature range for partial melting, particularly at higher P O2 (0.1-1.0 atm).
Hence, the two-step heat treatment heals cracks and other defects. The partial melting during the final part of the process can perform two tasks. Firstly, the final conversion of the oxide phases to the desired oxide superconductor phase is kinetically enhanced by the presence of the liquid phase, in part, due to the enhanced diffusivity of the oxide superconductor constituents. The conversion rate of BSCCO 2212 to BSCCO 2223, for example, is greatly accelerated, allowing the formation of a microscopically crack-free, interconnected BSCCO 2223 phase. Secondly, the cracks formed during the prior deformation or cabling steps are healed by rapid growth of the oxide superconductor grains at the crack site.
Various processing parameters can be controlled to obtain the necessary partial melt and oxide reforming steps. For example, P O2 can be held constant and temperature can be raised to promote melting and formation of the liquid phase and lowered to regenerate the desired oxide superconductor. Alternatively, temperature can be held constant, and P O2 can be lowered to promote the partial melting of the oxide superconductor article and raised to reform the oxide superconductor. For constant P o2 conditions, temperature should increase and for constant temperature conditions, P O2 should decrease sequentially through the two-step process. Thus, conditions are selected which give a two-step process, in which the thermodynamic state is changed from the first to the second condition. Ideally the thermodynamic state is altered so as to destabilize the liquid in the second step with respect to the desired oxide phase superconductor. This is in contrast to systems in which conditions are varied between a first and second step, but in which such adjustments to not change the thermodynamic state of the system with respect to the stability of the liquid phase.
The processing conditions can be changed rapidly from point 12 to point 13 of the process (fast ramp rate). Alternatively, the oxide superconductor can be subjected to gradually changing conditions (of temperature or pressure) between point 12 and point 13 of the process designated by the curve 14 in FIG. 1 (slow ramp rate). In another alternative embodiment, there need be no “hold” at 13 . The processing conditions can be slowly ramped from the processing conditions defined at point 12 to the processing conditions defined for point 13 . This process is illustrated by curve 15 in FIG. 1 .
The method of forming textured oxide superconducting cables is described with reference to oxides of the BSCCO family; however, this is in no way meant to limit the scope of the invention. The present invention can be practiced with any oxide superconductor system in which a liquid phase co-exists with an oxide superconductor phase such that an irreversible melt occurs and which is amenable to deformation-induced texture processing.
Methods of obtaining highly textured oxide superconducting strands using the two-step heat treatment of the invention is described in detail in U.S. Ser. No. 08/041,822 which is now issued as U.S. Pat. No. 5,635,456 and is incorporated herein by reference. FIG. 2 shows a processing profile for a method of the invention used to obtain highly textured oxide superconductor cable using this two-step heat treatment. The cabling operation may be performed at various stages in the process, as is discussed hereinbelow.
In a preferred embodiment, an oxide superconductor precursor is subjected to one or more first anneal/deformation iterations, denoted by step 20 and step 21 , respectively, of FIG. 2 . The oxide superconductor precursor can be any combination of materials which will yield the desired oxide superconductor upon reaction. In particular, it may be a metallic alloy containing the metallic constituents of the desired oxide superconductor and optionally containing silver. Alternatively, the constituent simple metal oxides, mixed metal oxides, metal salts and even intermediate oxide superconductors of the desired oxide superconductor may be used as a precursor. The precursor may optionally be mixed with a matrix metal, such as silver, and/or may be sheathed in a matrix material in a powder-in-tube configuration.
The anneal 20 of the anneal/deformation iteration serves two purposes in the process. Firstly, the anneal is sufficient to form an oxide superconductor and results typically in a mixture of superconducting and secondary phases. “Secondary phases” include sub-oxide or non-superconducting oxide species which require further processing to form an oxide superconductor phase. BSCCO-2212 is often the intermediate oxide superconductor because it is readily textured during mechanical deformation. BSCCO-2223 is the typical desired oxide superconducting phase because of its high critical temperature. Secondly, the anneal promotes reaction-induced texture.
The deformation 21 of the article promotes deformation-induced texture. One or more iterations can be performed. FIG. 2 shows two first anneal/deformation iterations, by way of example only. If more than one iteration is performed, both conversion to the superconducting phase and development of texture can be done in incremental stages.
If the desired oxide superconductor is not formed in the first anneal/deformation iterations, the second step of the process may consist of one or more second anneal/deformation iterations to form the desired oxide superconductor and to further texture the oxide superconductor phase. The article is annealed in a step indicated by 22 whereby the desired oxide superconductor is formed and reaction-induced texture can occur. Secondary phases react with BSCCO-2212 to form the desired oxide superconductor, BSCCO-2223. The article is deformed in a subsequent step indicated by 23 , whereby deformation-induced texture can occur. One or more second anneal/deformation iterations can be performed. FIG. 2 shows two iterations, by way of example only. If more than one iteration is used, only a portion of the intermediate oxide superconductor, need be converted into the desired oxide superconductor with each iteration. Conditions known to form intermediate and desired oxide superconductors are well known in the art. Suitable conditions are described in Sandhage, et al. JOM, 21 (Mar. 1991), hereby incorporated by reference.
Practically, the incremental improvement in alignment for both anneal/deformation cycles will decrease markedly after several iterations, however, there is no theoretical limit to the number of iterations that can be used. The strain introduced in the deformation step can range up to 99%. The strains applied in each deformation/anneal iteration may be constant or they may be changed for each subsequent iteration. It is particularly desirable in some embodiments, to use decreasing strains with each subsequent iteration.
It is also possible to adjust the processing conditions to promote partial melting during the anneal 20 or 22 of the anneal/deformation iterations, indicated by step 24 , to assist in grain growth and enhance reaction kinetics (reaction-induced texture). An anneal in the range of 820-835° C. in 0.075 atm O 2 and 1 atm total pressure for 0.1 to 100 hours is typical for partial melting to occur.
The above description is directed to the formation of a textured oxide superconductor within the individual strands. A cabling step 30 may be carried out at a number of stages during the processing of the oxide superconductor cable, designated 30 a , 30 b , 30 c , 30 d in FIGS. 2 and 3. The choice of when in the process to cable the oxide strands depends upon the nature of the oxide superconductor and the type of cabling operation to be performed. Generally, cabling early in the manufacturing process is preferred to get uniform good direction texture independent of cabling style; also earlier cabling may be preferred to minimize strain. It also may be desirable to coat each individual oxide superconductor strand with an insulating layer, such as for example, MgO prior to cabling. Alternatively, the final cabled article may be coated with an insulating layer. Coordination of oxide superconductor formation and cabling operation is shown in FIG. 3 .
In one embodiment, the oxide superconductor strand is processed by one or more suitable texturing methods in order to convert the precursor into the desired oxide superconductor and to substantially completely texture the oxide superconductor. In the most preferred embodiment illustrated in FIG. 3 ( a ), the texturing is accomplished by successive anneal/deformation iterations. Thereafter, the textured oxide strands are cabled in a step 30 a (see, FIGS. 2 and 3 ). The cable is then subjected to the final two-step heat treatment of the invention in order to heal the defects introduced in the cabling step, and if deformation was performed, in the deformation steps.
In another embodiment illustrated in FIG. 3 ( b ), the oxide superconductor strand is processed by successive anneal/deformation iterations in order to convert the precursor into the desired oxide superconductor and to substantially completely texture the oxide superconductor. A two-step heat treatment of the invention is performed in order to heal defects (microcracks and the like) introduced in the deformation processing steps. Thereafter, the individual oxide superconductor strands are cabled in a step 30 b (see, FIGS. 2 and 3 ). A final two-step heat treatment of the invention is performed in order to heal defects introduced in the cabling process. It is recognized that other wire processing operations may benefit from the two-step heat treatment of the invention. For example, coil formation and spooling at small radii of curvature may introduce bending strains similar to those introduced in cabling operations. It is expected that performing a two-step heat treatment of the invention will benefit current carrying properties after these operations as well. The processes illustrated in FIGS. 3 ( a ) and 3( b ) benefit from the full texturing of the individual oxide strands before the cabling process. While optimal texturing in the individual strands is beneficial to current carrying capacity, the oriented strands may have a lower tolerance to bending strains.
Another embodiment is illustrated in FIG. 3 ( c ). The oxide superconductor strand is processed as above by successive texturing operations, preferably including successive anneal/deformation iterations, in order to convert the precursor into the desired oxide superconductor and to texture the oxide superconductor. At some point during this iterative process, the not-yet-fully-reacted- and-textured oxide superconductor strands are cabled in a step 30 c (see, FIGS. 2 and 3 ). Further texturing is performed on the cable to complete the reaction to the oxide superconductor and to fully texture the oxide superconductor. Thereafter, a final two-step heat treatment is performed in order to heal defects introduced by both the deformation and cabling processes. A typical processing sequence may include a first anneal and deformation ( 20 , 21 ), a cabling operation ( 30 c ), and a second anneal and deformation ( 22 , 23 ), followed by the final two-step heat treatment of the invention.
In yet another embodiment of the invention, the cabling operation is performed on a precursor strand before a significant texture is developed in strands and while density is low. Thereafter, a two-step heat treatment is performed in order to heal defects introduced by the cabling processes, and texturing is completed. FIG. 3 ( d ) illustrates one such approach, in which the cabling operation 30 d is performed on a precursor strand prior to a series of successive texture-inducing deformation and reaction iterations (see, FIGS. 2 and 3) where the number of iterations, n, can vary from zero to five, and a final two-step heat treatment heals defects induced by both the cabling and deformation steps. However, a plurality of two step heat treatments might equally be performed. Because the cabling operation illustrated in FIGS. 3 ( c ) and 3 ( d ) is performed on the oxide superconductor strands that are not fully textured, that is, the aspect ratio of the oxide grains is less than optimal and the density is relatively low, it may be expected that the deleterious effect of cabling on the critical current density is reduced; however, subsequent texturing operations may be less efficient due to the varied strand orientations after cabling.
The oxide superconductors which make up the oxide superconductor cables of the present invention are brittle and typically would not survive a mechanical deformation process, such as rolling or pressing. For this reason, the oxide superconductors of the present invention are typically processed as a composite material including a malleable matrix material. In particular, silver is preferred as the matrix material because of its cost, nobility and malleability; however, other noble metals may be used. A metal is considered noble when it is inert to oxidation and chemical reaction under the processing conditions of the oxide superconductor. The oxide superconductor strands may be processed in any shape, however, the form of wires, tapes, rings or coils are particularly preferred. The oxide superconductor strand may be encased in a silver sheath, in a version of the powder-in-tube technology. The oxide superconductor strand can take the form of multiple filaments embedded within a silver matrix. For further information on superconducting tapes and wires; see, Sandhage et al.
EXAMPLE 1
The following example describes the manufacture of an oxide superconductor strand for use in the cabling operations of the present invention which is described in U.S. Ser. No. 08/041,822 and is hereby incorporated by reference, and compares the transport critical current characteristics of a samples treated with the two-step heat treatment of the present invention to those of conventionally processed samples.
Precursor powders were prepared from the solid state reaction of freeze-dried precursor of the appropriate metal nitrates having the nominal composition of 1.7:0.3:1.9:2.0:3.1 (Bi:Pb:Sr:Ca:Cu). Bi 2 O 3 , CaCO 3 , SrCO 3 , Pb 3 O 4 and CuO powders could be equally used. After thoroughly mixing the powders in the appropriate ratio, a multistep treatment (typically, 3-4 steps) of calcination (800° C.±10° C., for a total of 15 h) and intermediate grinding was performed in order to remove residual carbon, homogenize the material and to generate the low T c BSCCO-2212 oxide superconductor phase. The powders were packed into silver sheaths having an inner diameter of 0.625″ (1.5875 cm) and a length of 5.5″ (13.97 cm) and a wall thickness of 0.150″ (0.38 cm) to form a billet.
The billets were extruded to a diameter of ¼″ (0.63 cm). The billet diameter was narrowed with multiple die passes, with a final pass drawn through a 0.070″ (0.178 cm) hexagonally shaped die into silver/oxide superconductor hexagonal wires. Nineteen of the wires were bundled together and drawn through a 0.070″ (0.178 cm) round die to form a multifilamentary round wire. The round wire was rolled to form a 0.009″×0.100″ (0.023 cm×0.24 cm) multifilamentary strand.
A length of the multifilamentary strand was then subjected to a heat treatment according to the invention. The composite strand was heated in a furnace in a first anneal at 820° C. in 0.075 atm O 2 for 48 h. The first anneal formed significant amounts of the desired oxide superconductor phase, BSCCO-2223. The composite strand was then rolled to reduce thickness by 11% (0.009″ to 0.008″). Lastly, the rolled composite strand was subjected to a final two-step heat treatment, namely, heating from room temperature at a rate of 1° C./min to 820° C. in 0.075 atm O 2 and holding for 54 h, cooling to 810° C. in 0.075 atm O 2 and holding for 30 h. The sample was furnace cooled to room temperature in 1 atm P O2 .
A length of multifilamentary strand was also subjected to a conventional heat treatment. The composite strand was heated in a furnace in a first anneal at 820° C. in 0.075 atm O 2 for 48 h. The first anneal caused significant amounts of the desired oxide superconductor phase, BSCCO-2223 to form. The multifilamentary strand was then rolled to reduce thickness by 11% (0.009″ to 0.008″). The control samples were then subjected to a second anneal at 810° C. in 0.075 atm O 2 for 84 h. This was a single step heat treatment in which no melting of the sample occurs.
The microstructure of the samples were evaluated under an optical microscope. The samples prepared according to the method of the invention had a higher density and far less cracks than the control samples.
The critical currents of the samples using a criterion of 1 μV/cm, 77 K and zero applied field were determined. A single critical current was determined end-to-end over a long length of strand (7-10 m). Critical current for a number of 10 cm lengths of composite strands were determined and an average value was determined. The results are reported in Table 1 and show that samples processed according to the method of the invention exhibited a factor of at least two improvement in critical transport properties.
TABLE 1
A comparative study of the method of the invention with
a conventional process.
sample no.
length (m)
I c (A)
% σ
J c (A/cm 2 )
Example 1-1
10
6.05
—
7563
Example 1-2
0.1
9.52
13
11,900
Control 1-1
7
2.23
—
2788
Control 1-2
0.1
4.08
16
5100
Further demonstrations of the superior performance of oxide superconductor strands prepared using a final two-step heat treatment of the invention are found in U.S. Ser. No. 08041,822, incorporated herein by reference.
EXAMPLE 2
This example demonstrates the manufacture of a multistrand power cable using oxide superconductor strands.
Precursor powders were prepared from the solid state reaction of freeze-dried precursor of the appropriate metal nitrates having the nominal composition of 1.7:0.3:1.9:2.0:3.1 (Bi:Pb:Sr:Ca:Cu). Bi 2 O 3 , CaCO 3 , SrCO 3 , Pb 3 O 4 and CuO powders could be equally used. After thoroughly mixing the powders in the appropriate ratio, a multistep treatment (typically, 3-4 steps) of calcination (800° C.±10° C., for a total of 15 h) and intermediate grinding was performed in order to remove residual carbon, homogenize the material and to generate the low T c BSCCO-2212 oxide superconductor phase. The formulated powder was packed into the open end of a silver billet under hydraulic pressure. The silver billet was open at one end and closed at the other and had a length of 8.00″±0.15″ (20.32 cm), an outer diameter of 1.25″±0.005″ (3.18 cm) and a inner diameter of 0.85″±0.005″ (2.16 cm).
The billets were extruded to a diameter of 0.5″ (1.27 cm), then were placed into a furnace at 450° C. for one hour to anneal. The billets were drawn through progressively smaller round dies until they reach a diameter of 0.0785″ (0.199 cm). Each pass through the die reduced the diameter by 5% to 11%. The next step was to draw the wires through hexagonal shaped dies to their final hexagonal wire dimension of 0.070″ (0.178 cm).
The hexagonal shaped wires were cleaned with suitable cleaning agents; then cut into 85 equal lengths; and then grouped together to form a hexagonal shaped bundle. The bundle was inserted into a pure silver tube having an outer diameter of 0.840″±05.015″ (2.133 cm) and an inner diameter of 0.760″±0.0015″ (1.93 cm). After bundling, the multifilament bundle was placed in a furnace at 450° C. for four hours to anneal. The annealed multifilamentary bundle was allowed to cool before it is drawn through a round die of progressively smaller dimension until it reached the final wire diameter of 0.072″ (0.183 cm). The wire was place into a furnace at 600° C. for 2 hours to thermally bond the assembly.
The round strand was then rolled in three reduction passes to a final dimension of 0.010 inch (0.025 cm)×0.0100 inch (0.254 cm) with intermediate heat treatments in which the strand is ramped to 815° C. at 1° C./min, held at 815° C. for 16 hours and cooled to room temperature, all at 7.5% oxygen. After a final anneal at 450° C. for one our, twelve lengths of the strand were cut to about 8 inches for cabling.
FIG. 4 is a side view of a cabling operation used to form the cable of the present invention. It is understood that the hand assembly described in this example could be readily substituted by commercially available processes, such are currently used in the cable industry.
Using a protractor, a silver tube 40 is mounted in a vise 42 . The tube 40 may be mounted at an angle θ in the range of 0° to 40°, and preferably at a an angle of 25°±5°. With a sharp instrument, several guide lines were lightly scored into the silver tube at the angle θ set by the tube 40 . Twelve lengths of oxide superconducting strands 44 were cut to a length of about two inches longer than the tube 40 length. Six of the oxide strands 44 a are secured to an uppermost edge 45 of the tube 40 and were positioned so as to be aligned with the scored guidelines and/or to hang substantially perpendicular to the ground. Once aligned, the oxide strands 44 a are spiral wrapped around the tube 40 . The strands may be wrapped by rotation of the strands around a stationary tube or, in a preferred embodiment, by rotation of the tube, while maintaining the strands at the selected angle θ with respect to the tube. Once spiral wrapped, the strands are secured at the lowermost edge of the tube. The strands may be wrapped one at a time or simultaneously.
The above process is repeated at the complementary angle (−θ), so that the remaining six oxide superconducting strands 44 b are spiral wrapped in the opposite direction, such that a second layer of spiral wrapped strands is formed. The strands 44 a , 44 b are secured top and bottom with a silver wire 46 .
When the second layer is completed, the assembly is removed from the vise and lightly compressed in a hydraulic press at 10 Kpsig. The flattened cable assembly is subjected to a two-step heat treatment involving a 40 hour bake at 830° C. followed by a 40 hour bake at 811° C. followed by a 30 hour bake at 787° C. in 7.5% oxygen at one atmosphere total pressure. FIG. 5 shows the power consumption of the cabled conductor in watts/m of the cable per amp of applied current in magnetic fields of 0, 100, 326 and 1070 Gauss. FIG. 6 shows the VI characteristics of that same cabled conductor in the same applied magnetic fields and demonstrates that the cable has substantially linear VI characteristics.
Comparison Example 2
As a comparison, a cable was processed in substantially the same manner as described in Example 2, but without the final two-step heat treatment of the invention. the cable was evaluated for current carrying ability. The plot of electric field vs current plot at 77K shown in FIG. 7 demonstrates the VI characteristics of the cable. It can be seen that the cable was resistive and had no significant current carrying capability.
EXAMPLE 3
Square cross-sectioned (0.070″×0.070″) multifilamentary (1254 filaments) precursor alloy/silver composite wires having the appropriate stoichiometry for BSCCO-2223 were fabricated, and oxidized at 405° C. for 600 hours in 100 atm oxygen. After oxidation, they were reacted in 7.5% oxygen gas at one atmosphere total pressure for 6 hours to form BSCCO 2212+BSCCO 0011 reactant. They were then square bar rolled forward and in the reverse direction in 10% and 20% area reduction increments with anneals every third pass consisting of a 10 minute bake at 200° C. in air until they were 0.033″×0.033″ in cross-section (78% area reduction). They were then sheet rolled forward and in reverse at ambient temperature with a 2-high rolling mill with 4″ diameter rolls until their dimensions were 0.023″×0.045″ in cross-section (4 passes). A series of experiments were then completed to determine a suitable final heat treatment sequence for forming sintered and textured BSCCO 2223 from the textured BSCCO 2212+BSCCO 0011 as well as forming the wires into a cable via a planetary winding scheme such that they are separated by a fairly resistive layer in the cable.
In the best method, the wires were baked at 829° C. for about 10 hours in 7.5% oxygen at a total pressure of one atmosphere followed by sheet rolling to a 15% thickness reduction in one pass, and a second bake at 829° C. for about 10 hours in 7.5% oxygen gas at one atmosphere total pressure. The wires thus processed were then manually cabled to form 5-strand cable samples such that the same surface of each wire was parallel to the external cable surface regardless of position in the cable. The cable pitch was about 1.3″. The wires were cabled by bending them sequentially onto a 0.1″×0.01″ copper tape former without rotating the wire about its own or the cable axis, thereby preserving alignment of each wire surface with a corresponding surface of the cable. After cabling, the copper strip was removed.
Some wires were coated with MgO prior to and after cabling by dipping into a fine MgO powder/alcohol suspension and drying with forced hot air. The cables were then 2-high rolled with 4″ diameter rolls to a wire thickness reduction of 10%, thereby consolidating the cable into a well defined, structurally integral form. The cabled wires were then subjected to the two step heat treatment of the invention to sinter the BSCCO 2223. This heat treatment consisted of a 30 hour bake at 829° C. followed by a 60 hour bake at 811 ° C. followed by a 20 hour bake at 787° C. in 7.5% oxygen at one atmosphere total pressure.
The transport properties of the cables and co-processed un-cabled wires were measured at 77K in self field. The results are presented in Table 2.
TABLE 2
Results of Electrical Measurements
Cable Ic at
Sample History
Cable Type
77K (A)
1)
Cable, no MgO slurry
5-wire, 10% HTS oxide
6.0
fill factor
2)
Cable dipped in MgO
5-wire, 19% HTS oxide fill
10.1
slurry before the final
factor
heat treatment
3)
Cable dipped in MgO
5-wire, 19% HTS oxide fill
10.8
slurry after cabling
factor
EXAMPLE 4
Oxide superconducting strands were prepared according to Example 2. The oxide superconductor multistrand cable was assembled as follows.
Construction of the cable assembly is similar to that described in Example 2, except that two pieces of oxide superconductor wire having a diameter of 0.015″ and a composition of substantially BSCCO 2212 are used in place of the silver core tube. The two wires are secured together to form a core of 0.017″ thick and 0.300″ wide. Six strands of oxide superconductor strands prepared according to Example 2 above are spiral wrapped in one direction at an angle of 25° and six strands are wrapped in the other direction, also at an angle of 25°.
When the second layer is completed, the assembly is removed from the vise and lightly compressed in a hydraulic press at 10 Kpsig. The flattened cable assembly is subjected to a final two-step heat treatment of a 40 hour bake at 830° C. followed by a 40 hour bake at 811° C. followed by a 30 hour bake at 787° C. in 7.5% oxygen at one atmosphere total pressure.
EXAMPLE 5
Oxide superconducting strands were prepared according to Example 2. The oxide superconductor multistrand cable was assembled as follows.
A 0.003″ quartz sheet was laid our on a flat metal surface and saturated with polyvinyl alcohol (PVA). The PVA-saturated sheet was heated with an iron to thermoset the plastic. After heating, the quartz sheet was cut into one half inch strips. A six inch silver tube, such as that described in Example 2, was wrapped with the quartz strips. Construction of the cable assembly is similar to that described in Example 2. Six strands of oxide superconductor strands prepared according to Example 2 above are spiral wrapped in one direction at an angle of 25° and six strands are wrapped in the other direction, also at an angle of 25°.
When the second layer is completed, the assembly is removed from the vise and lightly compressed in a hydraulic press at 10 Kpsig. The flattened cable assembly is subjected to a final two-step heat treatment of to a final two-step heat treatment of a 40 hour bake at 830° C. followed by a 40 hour bake at 811° C. followed by a 30 hour bake at 787° C. in 7.5% oxygen at one atmosphere total pressure.
EXAMPLE 6
A 91 filament composite was made by the PIT process with an approximately a hexagonal array filament pattern using standard monofilament 2223 precursor in a fine Ag sheath. Precursor powders were prepared from the solid state reaction of freeze-dried precursors of the appropriate metal nitrates having the nominal composition of 1.8:0.3:1.9:2.0:3.1 (Bi:Pb:Sr:Ca:Cu)]. Bi 2 O 3 , CaCO 3 , SrCO 3 , Pb 3 O 4 , and CuO powders could equally be used. After thoroughly mixing the powders in the appropriate ratio, a multistep treatment (typically 3-4 steps) of calcination (800° C.±10° C., for a total of 15 h) and intermediate grinding was performed in order to remove residual carbon, homogenize the material and generate a BSCCO 2212 oxide superconductor phase. The powders were packed into silver sheaths to form a billet. The billets were extruded to a diameter of about ½ inch (1.27 cm) and annealed at 450 C. for 1 hour. The billet diameter was narrowed with multiple die steps, with a final step drawn through a hexagonally shaped die into a silver/precursor hexagonal monofilament wires.
Eighty-nine wires 0.049×0.090″, one 0.1318 round and one 0.055 round wires were assembled and inserted into a 0.840″ outer diameter by 0.740″ inner diameter silver tube to form a bundle. The assembly was baked for four hours at 450 degrees the bundle was allowed to cool and then drawn through to 0.072 via successive 20% and 10 % pass reductions to for a multi-filamentary round strand. At 0.072″ it was annealed at 450 degrees for one hour, allowed to cool and drawn to 0.0354″ It was again annealed at 450 degrees C. for one hour, allowed to cool and then drawn to 0.0245″ diameter. The composite was annealed in air at 300 C. for nominally 10 minutes. The material was divided approximately equally into 8 parts and each was layer wound onto a cabling spool.
An 8 strand Rutherford cable was made from 91 filament composite strand. A rigid cabling configuration was used, where the spools' orientation are fixed relative to the rotating support that holds them. The tension on each strand was controlled by magnetic breaks and set to nominally 0.5 inch-pounds. The width and thickness of the cable were set by a non-powered turks-head to be 0.096 and 0.048 inch, respectively. The cable lay pitch was set by a capstan take-up speed relative to the rotations speed to be nominally 1.03 inch. After cabling, the material was heat treated at 760 C. for 2 hr. in 0.1 atm of oxygen. The cable was then rolled to at thickness of 0.0157 inch and heat treated for 6 hr. at 827 C. in 7.5 % oxygen in nitrogen atmosphere. The cable was finally turks head rolled to 0.0126 inch in thickness. A final heat treatment of 40 hr. at 827 C., 30 hr. at 808 C., and 30 hr. at 748 C., all in 0.075 atm of oxygen in nitrogen was employed. The Je at 77K (B=0) was 2996 A/cm 2 at a fill factor of nominally 25 % superconductor cross section.
As can be seen by the above examples, the method of the invention is highly versatile and can be successfully used with a variety of deformation processes, oxide superconductor compositions, silver alloy compositions and processing conditions.
Other embodiments of the invention will be apparent to those skilled in the art from a consideration of the specification or practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only, with the true scope and spirit of the invention being indicated by the following claims. | A method for preparing an oxide superconductor cable includes transposing a plurality of oxide superconductor strands along a longitudinal axis so as to form a cable and exposing the cable to a two step heat treatment after cabling of the oxide strands, the heat treatment comprising, (a) heating the cable to and maintaining the cable at a first temperature sufficient to partially melt the article, such that a liquid phase co-exists with the desired oxide superconductor phase; and (b) cooling the cable to and maintaining the cable at a second temperature sufficient to substantially transform the liquid phase into the desired oxide superconductor. The oxide superconductor multistrand cable includes a plurality of oxide superconductor strands, each of the strands including an oxide superconductor having an irreversible melt characteristic, wherein the plurality of oxide strands are transposed about a longitudinal axis, such that each of the strands are substantially electrically and substantially mechanically isolated; and wherein the cable exhibits critical transport properties (J c ) of at least about 10,000 A/cm 2 at 77K, self field. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a process for the preparation of a dispersion of a water-soluble cationic polymer which is useful as a flocculant or dehydrating agent for waste water disposal or as a papermakers chemical.
2. Description of the Prior Art
Known processes for the preparation of a water-soluble cationic polymer which is useful as a flocculant for waste water disposal or as a papermakers chemical include standing polymerization in an aqueous solution, water-in-oil emulsion polymerization (see, for example, Japanese Patent Laid-Open No. 102388/1979), suspension polymerization in a hydrophobic solvent (see, for example, Japanese Patent Laid-Open No. 69196/1979) and so on.
Further, there has been disclosed a process for preparing a water-soluble, nonionic or anionic polymer by precipitation polymerization in an aqueous solution of ammonium sulfate (see, for example, Japanese Patent Laid-Open No. 70489/1975).
Also there have been disclosed a process for carrying out the polymerization in an aqueous solution of a salt in the presence of a polyhydric alcohol (see, for example, Japanese Patent Laid-Open No. 20502/1987) and a process for carrying out the polymerization in an aqueous solution of a salt in the presence of a polyelectrolyte as a dispersant (see, for example, Japanese Patent Laid-Open Nos. 123610/1986 and 20511/1987).
The standing polymerization in an aqueous solution, however, must be carried out with a monomer concentration of at least 10% by weight in order to obtain a high-molecular weight polymer. Therefor, the product is given in a state of water-containing gel, so that it is difficult to dissolve the product as such. Accordingly, the product must be put on the market in a state of a low-concentration solution obtained by further diluting a product or must be dried and powdered. With respect to the low-concentration solution, the transportion cost is disadvantageously enhanced, while with respect to the powdering of the product, much heat energy is necessitated for drying the product and the product disadvantageously causes three-dimensional crosslinking by heating to insolubilize a part thereof.
Meanwhile, the water-in-oil emulsion polymerization has a problem that a flammable and valuable organic solvent is consumed wastefully. Further, the suspension polymerization in a hydrophobic solvent has a problem that the production equipment costs a great deal, because a flammable material such as cyclohexane or toluene is used. The precipitation polymerization in an aqueous solution of ammonium sulfate has a problem that the formed polymers adhere to each other to form big lumps, resulting in difficult handling, though it is a preferable method with a low cost of equipment. Furthermore, it is difficult to prepare a polymer in a state of fine particle by using a conventional dispersant.
SUMMARY OF THE INVENTION
An object of the present invention is to solve the above problems. More precisely, the present invention relates to a process for dispersing a water-soluble cationic polymer in an aqueous solution of a polyvalent anion salt in a state of fine particle. In other words, it aims at providing a process for the preparation of a dispersion of a water-soluble cationic polymer which is easily flowable and easily soluble in spite of its high molecular weight.
Another object of the present invention is to provide a process for the preparation of a dispersion of a water-soluble cationic polymer which comprises polymerizing a water-soluble monomer mixture containing at least 5 mole % of a cationic monomer represented by the general formula (I) in an aqueous solution of a polyvalent anion salt, characterized in that the polymerization is carried out in the presence of both a water-soluble cationic polymer which is insoluble in said aqueous solution of a polyvalent anion salt and a water-soluble cationic polymer which is soluble in said aqueous solution of a polyvalent anion salt, that said water-soluble cationic polymer insoluble in the aqueous solution of a polyvalent anion salt contains at least 5 mole % of cationic monomer units represented by the general formula (I) and that said water-soluble cationic polymer soluble in the aqueous solution of a polyvalent anion salt contains at least 20 mole % of cationic monomer unit represented by the general formula (II). ##STR1## wherein R 1 and R 4 are each H or CH 3 ; R 2 , R 3 , R 5 and R 6 are each an alkyl group having 1 to 2 carbon atoms; R 7 is a hydrogen atom or an alkyl group having 1 to 2 carbon atoms; A 1 and A 2 are each an oxygen atom or NH; B 1 and B 2 are each an alkylene group having 2 to 4 carbon atoms or a hydroxypropylene group and X 1 .sup.⊖ and X 2 .sup.⊖ are each a counter anion.
A still further object of the present invention is to provide a process for the preparation of a dispersion of a water-soluble cationic polymer which comprises polymerizing a water-soluble monomer mixture containing a cationic monomer represented by the general formula (I) in an aqueous solution of a polyvalent anion salt, characterized in that the formed water-soluble cationic polymer is precipitated in a state of fine particle and that the precipitation of the polymer is controlled so as to give the fine particle of the polymer.
Another object of the present invention is to provide a process for the preparation of a dispersion of a water-soluble cationic polymer, characterized in that, by precipitating a water-soluble cationic polymer in an aqueous solution of a polyvalent anion salt, the viscosity of the formed dispersion is lowered and the separation of the polymer in the aqueous solution is inhibited.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The process for the preparation of a dispersion of a water-soluble cationic polymer according to the present invention is characterized in that the three components which follow are coexistent at the beginning of the polymerization, though other components may, if necessary, be used additionally:
a water-soluble monomer mixture containing at least 5 mole % of a cationic monomer represented by the general formula (I): ##STR2## wherein R 1 is H or CH 3 ; R 2 and R 3 are each an alkyl group having 1 to 2 carbon atoms; A 1 is an oxygen atom or NH; B 1 is an alkylene group having 2 to 4 carbon atoms or a hydroxypropyl group and X 1 .sup.⊖ is a counter anion, an aqueous solution of a polyvalent anion salt in which the above water-soluble monomer mixture is soluble and the polymer of the monomer mixture is insoluble, and
a dispersant comprising a water-soluble cationic polymer insoluble in an aqueous solution of a polyvalent anion salt and a water-soluble cationic polymer soluble in an aqueous solution of a polyvalent anion salt as essential components.
The polyvalent anion salt to be incorporated in the aqueous solution according to the present invention is suitably a sulfate or phosphate and particular examples thereof include ammonium sulfate, sodium sulfate, magnesium sulfate, aluminum sulfate, ammonium hydrogenphosphate, sodium hydrogenphosphate and potassium hydrogenphosphate. In the present invention, these salts may be each used as an aqueous solution thereof having a concentration of 15% or above.
The above cationic monomer represented by the general formula (I) includes quaternary ammonium salts obtained by the reaction of benzyl chloride with dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, dimethylaminohydroxypropyl (meth)-acrylate or dimethylaminopropyl (meth)acrylamide. The monomer to be copolymerized with the cationic monomer represented by the general formula (I) includes (meth)acrylamide and cationic monomers represented by the general formula (II). ##STR3## wherein R 4 is H or CH 3 ; R 5 and R 6 are each an alkyl group having 1 to 2 carbon atoms; R 7 is H or an alkyl group having 1 to 2 carbon atoms; A 2 is an oxygen atom or NH; B 2 is an alkylene group having 2 to 4 carbon atoms or a hydroxypropylene group and X 2 .sup.⊖ is a counter anion.
Among the cationic monomers represented by the general formula (II), salts and methylated quaternary salts of dialkylaminoethyl (meth)acrylate are particularly preferred.
The cationic monomer represented by the general formula (II) is so highly hydrophilic that the excess use thereof hinders the precipitation of the generated polymer. Accordingly, the mol fraction of the cationic monomer represented by the general formula (II) must not exceed that of the monomer represented by the general formula (I). The polymerization concentration thereof is suitably selected in a range of 5 to 30% by weight.
Of the two polymers to be added before the beginning of the polymerization for the purpose of obtaining a fine dispersion, the water-soluble cationic polymer insoluble in an aqueous solution of a polyvalent anion salt is preferably a product prepared by the process for the preparation of a water-soluble cationic polymer according to the present invention, which is because the dispersion prepared according to the present invention is easily handlable owing to its low viscosity (as compared with a case of adding the polymer as a viscous solution).
The monomer composition of the polymer to be added need not always be equal to that of the objective polymer.
Meanwhile, the water-soluble cationic polymer soluble in an aqueous solution of a polyvalent anion salt which is the other polymer is a cationic polymer comprising at least 20 mole % of a cationic monomer represented by the general formula (II) and the balance of (meth)acrylamide. These two polymers are each added in an amount of 1 to 10% by weight based on the total amount of the monomers used. The coexistence of a polyhydric alcohol such as glycerin or polyethylene glycol often further improves the state of precipitation.
The polymerization according to the present invention is carried out by the use of a conventional water-soluble free-radical initiator. It is particularly preferable to use a water-soluble azo compound such as 2,2'-azobis(2-amidinopropane) hydrochloride or 2,2'-azobis(N,N-dimethyleneisobutyramidine) hydrochloride. The additional dissolution of various salts in the polymer dispersion after the completion of the polymerization is effective in lowering the viscosity of the polymer dispersion and in making the specific gravity of the aqueous solution equal to that of the polymer particle. It is preferable from the standpoint of workability that the viscosity of the dispersion be 1000 cP or below, while it is effective in inhibiting the separation of the polymer that the polymer particle and the aqueous solution have specific gravities equal to each other.
The process for the preparation of a dispersion of a water-soluble cationic polymer according to the present invention is characterized in that the polymerization is carried out in an aqueous solution of a polyvalent anion salt to precipitate the generated water-soluble cationic polymer and that the precipitation is controlled so as to give the fine particle of the polymer. In this connection, the precipitation of a polymer with an aqueous solution of a polyvalent anion salt is a known phenomenon which is easily illustrated based on the Hofmeister's series.
In the process for the preparation of a dispersion of a water-soluble cationic polymer according to the present invention, the benzyl group-containing cationic monomer unit represented by the general formula (I) is particularly easily salted out and an amide group is next easily salted out. The mechanism as to how the two polymers are added as dispersants and exhibit the effects is presumably that a suitable polymerization field is provided and the association is hindered by an electrical repulsive force, though it is not apparent. Particularly, a water-soluble cationic polymer insoluble in an aqueous solution of a polyvalent anion salt exhibits such complicated behavior as the dissolution thereof in the aqueous solution in the presence of the monomers.
EXAMPLE
Examples of the process for the preparation of a dispersion of a water-soluble cationic polymer according to the present invention will now be described, though the present invention is not limited to the following Examples, but includes all embodiments as far as they are not deviated from the scope of the technical idea constituted of the matters described in the claim. Example 1
2.5 g of an acryloyloxyethyldimethylbenzylammonium chloride-acrylamide copolymer having a degree of cationization of 10 mole %, 2.5 g of polyacryloyloxyethyltrimethylammonium chloride, 335 g of ion-exchanged water, 112.5 g of ammonium sulfate, 35.1 g of acrylamide and 14.9 g of acryloyloxyethyldimethylbenzylammonium chloride were placed in a 1 l five-necked separable flask fitted with a stirrer, a thermometer, a reflux condenser and a nitrogen inlet tube. The resulting system was purged with nitrogen. 1 ml of a 1% aqueous solution of 2,2'-azobis(2-amidinopropane) hydrochloride was added to the flask to carry out the polymerization at a bulk temperature of 50° C. for 10 hours. The particle size of the polymer in the obtained dispersion was 10 μm or below and the viscosity of the dispersion was 500 cP.
Comparative Example 1
335 g of ion-exchanged water, 112.5 g of ammonium sulfate, 35.1 g of acrylamide and 14.9 g of acryloyloxyethyldimethylbenzylammonium chloride were placed in the same five-necked separable flask as that used in Example 1. The resulting system was purged with nitrogen. 1 ml of a 1% aqueous solution of 2,2'-azobis(2-amidinopropane) hydrochloride was added to the flask to carry out the polymerization at a bulk temperature of 50° C. for 10 hours. The particle size of the obtained polymer was 2 to 3mm and the polymer immediately settled out.
Example 2
17.5 kg of ion-exchanged water, 5 kg of ammonium sulfate, 3.2 kg of acrylamide, 1.33 kg of acryloyloxyethyldimethylbenzylammonium chloride, 1.1 kg of a 20% aqueous solution of polyacryloyloxyethyltrimethylammonium chloride and 1.5 kg of the polymer dispersion prepared in Example 1 were placed in a 35 l jacketed reaction vessel made of stainless steel and fitted with an agitating blade of a ribbon type. The resulting system was purged with nitrogen. 1 g of 2,2'-azobis(2-amidinopropane) hydrochloride was added to the vessel to carry out the polymerization at a bulk temperature of 50° C. for 10 hours. The particle size of the polymer in the obtained dispersion was 10 μm or below and the viscosity of the dispersion was 2500 cP. 1.3 kg of ammonium sulfate was further added to the dispersion. The viscosity of the resulting dispersion was 230 cP, though the particle size was unchanged.
Comparative Example 2
17.5 kg of ion-exchanged water, 5 kg of ammonium sulfate, 3.2 kg of acrylamide, 1.33 kg of acryloyloxyethyldimethylbenzylammonium chloride and 1.1 kg of a 20% aqueous solution of polyacryloyloxyethyltrimethylammonium chloride were placed in the same reaction vessel as that used in Example 2. The resulting system was purged with nitrogen. 1 g of 2,2'-azobis(2-amidinopropane) hydrochloride was added to the reaction vessel to carry out the polymerization at a bulk temperature of 50° C. for 10 hours. The particle size of the polymer in the obtained dispersion was 100 μm.
Example 3
15.7 kg of ion-exchanged water, 4.6 kg of ammonium sulfate, 2.1 kg of acrylamide, 3.1 kg of acryloyloxyethyldimethylbenzylammonium chloride, 0.9 kg of acryloyloxyethyltrimethylammonium chloride, 0.1 kg of glycerin, 1.5 kg of a 20% aqueous solution of polyacryloyloxyethyltrimethylammonium chloride and 1.5 kg of the polymer dispersion prepared in Example 1 were placed in the same reaction vessel as that used in Example 2. The resulting system was purged with nitrogen. 1 g of 2,2'-azobis(2-amidinopropane) hydrochloride was added to the reaction vessel to carry out the polymerization at a bulk temperature of 50° C. for 10 hours. The particle size of the polymer in the obtained dispersion was 10 μm or below and the viscosity of the dispersion was 3200 cP. 2.1 kg of ammonium sulfate was further added to the dispersion. The viscosity of the resulting dispersion was 280 cP, though the particle size was unchanged. Comparative Example 3
15.7 kg of ion-exchanged water, 4.6 kg of ammonium sulfate, 2.1 kg of acrylamide, 0.9 kg of acryloyloxyethyltrimethylammonium chloride, 0.1 kg of glycerin and 1.5 kg of a 20% aqueous solution of polyacryloyloxyethyltrimethylammonium chloride were placed in the same reaction vessel as that used in Example 2. The resulting system was purged with nitrogen. 1 g of 2,2'-azobis(2-amidinopropane) hydrochloride was added to the reaction vessel at a bulk temperature of 50° C. for 10 hours. The particle size of the polymer in the obtained dispersion was about 100 μm. Example 4
17.0 kg of ion-exchanged water, 4.2 kg of ammonium sulfate, 0.4 kg of acrylamide, 3.9 kg of acryloyloxyethyldimethylbenzylammonium chloride, 1.7 kg of acryloyloxyethyltrimethylammonium chloride and 2.5 kg of a 20% aqueous solution of polyacryloyloxyethyltrimethylammonium chloride were placed in the same reaction vessel as that used in Example 2, followed by the addition of 2.5 kg of a fine dispersion of an acrylamide-acryloyloxyethyldimethylbenzylammonium chloride copolymer having a degree of cationization of 80 mole % (containing 20% by weight of the copolymer and 20% by weight of ammonium sulfate). The resulting system was purged with nitrogen. 1 g of 2,2'-azobis(N,N'-dimethyleneisobutyramidine) hydrochloride was added to the reaction vessel to carry out the polymerization at a bulk temperature of 45° C. for 10 hours. After the completion of the polymerization, 0.5 kg of ammonium chloride was added to the reaction vessel. The particle size of the polymer in the obtained dispersion was about 10 μm or below and the viscosity of the dispersion was 400 cP.
Comparative Example 4
17.0 kg of ion-exchanged water, 4.2 kg of ammonium sulfate, 0.4 kg of acrylamide, 3.9 kg of acryloyloxyethyldimethylbenzylammonium chloride, 1.7 kg of acryloyloxyethyltrimethylammonium chloride and 2.5 kg of a 20% aqueous solution of polyacryloyloxyethyltrimethylammonium chloride were placed in the same reaction vessel as that used in Example 2. The resulting system was purged with nitrogen. 1 g of 2,2'-azobis(N,N'-dimethyleneisobutyramidine) hydrochloride was added to the reaction vessel to carry out the polymerization at a bulk temperature of 45° C. for 10 hours. After the completion of the polymerization, 0.5 kg of ammonium chloride was added to the vessel, followed by mixing. The particle size of the polymer in the obtained dispersion was about 100 μm.
Example 5
18.3 kg of ion-exchanged water, 1.5 kg of anhydrous sodium sulfate, 3.5 kg of anhydrous aluminum sulfate, 3.1 kg of acrylamide, 1.4 kg of acrylamidopropyldimethylbenzylammonium chloride, 1 kg of a 20% aqueous solution of polyacrylaminopropyltrimethylammonium chloride and 0.2 kg of an acrylamidopropyldimethylbenzylammonium chlorideacrylamide copolymer having a degree of cationization of 10 mole % were placed in the same reaction vessel as that used in Example 2. The resulting system was purged with nitrogen. 1 g of 2,2'-azobis(2-amidinopropane) hydrochloride was added to the vessel to carry out the polymerization at a bulk temperature of 50° C. for 10 hours. The particle size of the polymer in the obtained dispersion was 10 μm or below and the viscosity of the dispersion was 3000 cP. 1 kg of sodium chloride was added to the dispersion. The viscosity of the resulting dispersion was 780 cP, though the particle size was unchanged.
Comparative Example 5
18.3 kg of ion-exchanged water, 1.5 kg of anhydrous sodium sulfate, 3.5 kg of anhydrous aluminum sulfate, 3.1 kg of acrylamide, 1.4 kg of acrylamidopropyldimethylbenzylammonium chloride and 1 kg of a 20% aqueous solution of polyacrylamidopropyltrimethylammonium chloride were placed in the same reaction vessel as that used in Example 2. The resulting system was purged with nitrogen. 1 g of 2,2'-azobis(2-amidinopropane) hydrochloride was added to the reaction vessel to carry out the polymerization at a bulk temperature of 50° C. for 10 hours. The particle size of the polymer in the obtained dispersion was 100 μm. | The present invention relates to the preparation of a dispersion wherein a copolymer comprising an acrylic monomer containing a dialkylbenzylammonium group is dispersed in an aqueous solution of a salt as fine particle. Two cationic polymers are used in the polymerization of the above monomer in the aqueous solution of a salt. One of the cationic polymers is a (co)polymer comprising an acrylic monomer containing a trialkylammonium group which is soluble both in the aqueous solution of a salt and in water, while the other thereof is a copolymer comprising an acrylic monomer containing a dialkylbenzylammonium group which is soluble in water, but insoluble in the aqueous solution of a salt. The above aqueous solution of a salt is an aqueous solution of a polyvalent anion salt such as sulfate or phosphate. A dispersion of a water-soluble cationic polymer can be prepared by dissolving the above monomer in the aqueous solution and carrying out the polymerization in the presence of the above two polymers. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation of U.S. patent application Ser. No. 09/918,099, filed Jul. 30, 2001 now abandoned, which is a continuation of U.S. patent application Ser. No. 09/489,689, filed Jan. 24, 2000, now abandoned which claims the benefit of U.S. provisional patent application No. 60/117,875, filed Jan. 29, 1999.
BACKGROUND OF THE INVENTION
This invention relates to 5-arylsulfonyl-imidazo[1′,2′:1,6]pyrido[2,3-b]pyrazine-6-amines and related compounds. The compounds are selective inhibitors of phosphodiesterase type 4 (PDE4) and the production of tumor necrosins factor (TNF), and as such are useful in the treatment of respiratory, allergic, rheumatoid, body weight regulation, inflammatory and central nervous system disorders such as asthma, chronic obstructive pulmonary disease, adult respiratory diseases syndrome, shock, fibrosis, pulmonary hypersensitivity, allergic rhinitis, atopic dermatitis, psoriasis, weight control, rheumatoid arthritis, cachexia, Crohn's disease, ulcerative colitis, arthritic conditions and other inflammatory diseases, depression, multi-infarct dementia, and AIDS.
This invention also relates to a method of using such compounds in the treatment of the foregoing diseases in mammals, especially humans, and to pharmaceutical compositions containing such compounds.
Since the recognition that cyclic adenosine tri-phosphate (cAMP) is an intracellular second messenger, inhibition of the phosphodiesterases has been a target for modulation and, accordingly, therapeutic intervention in a range of disease processes. More recently, distinct classes of PDE have been recognized and their selective inhibition has led to improved drug therapy. More particularly, it has been recognized that inhibition of PDE4 can lead to inhibition of inflammatory mediator release and airway smooth muscle relaxation. Thus, compounds that inhibit PDE4, but which have poor activity against other PDE types, would inhibit the release of inflammatory mediators and relax airway smooth muscle without causing cardiovascular effects or antiplatelet effects.
Recent molecular cloning has revealed a complexity and diversity of PDE4 enzymes. It is now known that there are four distinct PDE4 isozymes (A, B, C and D), each encoded for by a separate gene. Kinetic studies of human recombinant materials suggest that these four isozymes may differ in their Km's and Vmax's for hydrolysis of cAMP. Analysis of tissue distribution of PDE4 mRNAs suggests that each isozyme may be localized in a cell-specific pattern.
SUMMARY OF THE INVENTION
The present invention relates to a compound of the formula
and the pharmaceutically acceptable salts thereof; wherein
a is 1, 2, 3 or 4;
X is CH or N;
R 1 and R 2 are each independently selected from hydrogen, (C 1 -C 6 )alkyl, cyano, amino, (C 1 -C 6 )alkylamino, ((C 1 -C 6 )alkyl) 2 amino, (C 3 -C 7 )cycloalkyl, (C 6 -C 10 )aryl and a saturated or unsaturated, cyclic or bicyclic (C 2 -C 9 )heterocyclic group containing as the heteroatom one to four of the group consisting of oxygen, sulfur, nitrogen or NR 6 wherein R 6 is hydrogen or (C 1 -C 6 )alkyl;
R 3 and R 4 are each independently selected from hydrogen, halo, (C 1 -C 6 )alkyl, (C 1 -C 6 )alkoxy, cyano, hydroxy, amino, (C 1 -C 6 )alkylamino, ((C 1 -C 6 )alkyl) 2 amino, (C 3 -C 7 )cycloalkyl, (C 3 -C 7 )cycloalkoxy, (C 6 -C 10 )aryl or a saturated or unsaturated, cyclic or bicyclic (C 2 -C 9 )heterocyclic group containing as the heteroatom one to four of the group consisting of oxygen, sulfur, nitrogen or NR 6 wherein R 6 is defined as above;
or R 1 and R 2 may be taken together with the carbons to which they are attached to form a compound of formula II
wherein
a, X, R 3 and R 4 are as defined above;
b is 1,2,3 or 4; and
R 5 is hydrogen, halo, (C 1 -C 6 )alkyl, (C 1 -C 6 )alkoxy, cyano, hydroxy, amino, (C 1 -C 6 )alkylamino, ((C 1 -C 6 )alkyl) 2 amino, (C 3 -C 7 )cycloalkyl, (C 3 -C 7 )cycloalkoxy, (C 6 -C 10 )aryl or a saturated or unsaturated, cyclic or bicyclic (C 2 -C 9 )heterocyclic group containing as the heteroatom one to four of the group consisting of oxygen, sulfur, nitrogen or NR 6 wherein R 6 is defined as above.
The term “alkyl”, as used herein, unless otherwise indicated, includes saturated monovalent hydrocarbon radicals having straight, branched or cyclic moieties or combinations thereof.
The term “a saturated or unsaturated, cyclic or bicyclic (C 2 -C 9 ) heterocyclic group containing as the heteroatom one to four of the group consisting of oxygen, sulfur, nitrogen or NR 6 wherein R 6 is as defined above”, as used herein, unless otherwise indicated, includes but is not limited to pyrrolidinyl, tetrahydrofuranyl, dihydrofuranyl, tetrahydropyranyl, pyranyl, thiopyranyl, aziridinyl, oxiranyl, methylenedioxyl, chromenyl, isoxazolidinyl, 1,3-oxazolidin-3-yl, isothiazolidinyl, 1,3-thiazolidin-3-yl, 1,2-pyrazolidin-2-yl, 1,3-pyrazolidin-1-yl, piperidinyl, thiomorpholinyl, 1,2-tetrahydrothiazin-2-yl, 1,3-tetrahydrothiazin-3-yl, tetrahydrothiadiazinyi, morpholinyl, 1,2-tetrahydrodiazin-2-yl, 1,3-tetrahydrodiazin-1-yl, tetrahydroazepinyl, piperazinyl, chromanyl, furyl, thienyl, thiazolyl, pyrazolyl, isothiazolyl, oxazolyl, isoxazolyl, pyrrolyl, triazolyl, tetrazolyl, imidazolyl, 1,3,5-oxadiazolyl, 1,2,4-oxadiazolyl, 1,2,3-oxadiazolyl, 1,3,5-thiadiazolyl, 1,2,3-thiadiazolyl, 1,2,4-thiadiazolyl, pyridyl, pyrimidyl, pyrazinyl, pyridazinyl, 1,2,4-triazinyl, 1,2,3-triazinyl, 1,3,5-triazinyl, pyrazolo[3,4-b]pyridinyl, cinnolinyl, pteridinyl, purinyl, 6,7-dihydro-5H-[1]pyrindinyl, benzo[b]thiophenyl, 5,6,7,8-tetrahydro-quinolin-3-yl, benzoxazolyl, benzothiazolyl, benzisothiazolyl, benzisoxazolyl, benzimidazolyl, thianaphthenyl, isothianaphthenyl, benzofuranyl, isobenzofuranyl, isoindolyl, indolyl, indolizinyl, indazolyl, isoquinolyl, quinolyl, phthalazinyl, quinoxalinyl, quinazolinyl and benzoxazinyl.
The term “halo”, as defined herein, includes fluoro, chloro, bromo or iodo.
Preferred compounds of formula I include those wherein X is nitrogen.
Other preferred compounds of formula I include those wherein R 1 is hydrogen, (C 1 -C 6 )alkyl, amino, cycloalkyl or (C 6 -C 10 )aryl.
Other preferred compounds of formula I include those wherein R 2 is hydrogen, (C 1 -C 6 )alkyl, amino, cycloalkyl or (C 6 -C 10 )aryl.
Other preferred compounds of formula I include those wherein R 3 is hydrogen, halo, (C 1 -C 6 )alkyl, (C 1 -C 6 )alkoxy, cyano, amino, hydroxy, cycloalkyl or (C 6 -C 10 )aryl.
Other preferred compounds of formula I include those wherein R 4 is hydrogen, (C 1 -C 6 )alkyl, (C 1 -C 6 )alkoxy, amino, hydroxy, cycloalkyl or (C 6 -C 10 )aryl.
Other preferred compounds of formula II include those wherein R 5 is hydrogen, halo, (C 1 -C 6 )alkyl, (C 1 -C 6 )alkoxy, cyano, amino, hydroxy, cycloalkyl or (C 6 -C 10 )aryl.
More preferred compounds of formula I include those wherein X is nitrogen; R 1 is hydrogen, (C 1 -C 6 )alkyl, amino, cycloalkyl or (C 6 -C 10 )aryl; R 2 is hydrogen, (C-C 6 )alkyl, amino, cycloalkyl or (C 6 -C 10 )aryl; R 3 is hydrogen, halo, (C 1 -C 6 )alkyl, cyano, amino, hydroxy, cycloalkyl or (C 6 -C 10 )aryl; and R 4 is hydrogen, (C 1 -C 6 )alkyl, amino, hydroxy, cycloalkyl or (C 6 -C 10 )aryl.
More preferred compounds of formula II include those wherein X is nitrogen; R 3 is hydrogen, halo, (C 1 -C 6 )alkyl, cyano, amino, hydroxy, cycloalkyl or (C 6 -C 10 )aryl; R 4 is hydrogen, (C 1 -C 6 )alkyl, amino, hydroxy, cycloalkyl or (C 6 -C 10 )aryl and R 5 is hydrogen, (C 1 -C 6 )alkyl, cyano, amino, hydroxy, cycloalkyl or (C 6 -C 10 )aryl.
Specific preferred compounds of formula I include the following:
5-[(4-methylphenyl)sulfonyl]-imidazo[1′,2′:1,6]pyrido[2,3-b]pyrazin-6-amine;
5-[(4-methylphenyl)sulfonyl]-[1,2,4]triazolo[4′,3′:1,6]pyrido[2,3-b]pyrazin-6-amine;
5-[(4-ethylphenyl)sulfonyl]-imidazo[1′,2′:1,6]pyrido[2,3-b]pyrazin-6-amine;
5-[(4-isopropylphenyl)sulfonyl]-imidazo[1′,2′:1,6]pyrido[2,3-b]pyrazin-6-amine;
5-[(4-propylphenyl)sulfonyl]-imidazo[1′,2′:1,6]pyrido[2,3-b]pyrazin-6-amine;
5-[(4-methoxyphenyl)sulfonyl]-imidazo[1′,2′:1,6]pyrido[2,3-b]pyrazin-6-amine;
5-[(4-ethylphenyl)sulfonyl]-[1,2,4]triazolo[4′,3′:1,6]pyrido[2,3-b]quinoxaline-4-amino;
5-[(4-fluorophenyl)sulfonyl]-imidazo[1′,2′:1,6]pyrido[2,3-b]pyrazin-6-amine;
5-[(4-chlorophenyl)sulfonyl]-imidazo[1′,2′:1,6]pyrido[2,3-b]pyrazin-6-amine;
5-[(3-methoxyphenyl)sulfonyl]-imidazo[1′,2′:1,6]pyrido[2,3-b]pyrazin-6-amine;
5-[(4-methoxyphenyl)sulfonyl]-[1,2,4]triazolo[4′,3′:1,6]pyrido[2,3-b]pyrazin-6-amine; and
5-[(4-methoxyphenyl)sulfonyl]-[1,2,4]triazolo[4′,3′:1,6]pyrido[2,3-b]quinoxaline-4-amine;
The present invention also relates to a pharmaceutical composition for the treatment of respiratory, allergic, rheumatoid, body weight regulation, inflammatory and central nervous system disorders such as asthma, chronic obstructive pulmonary disease, adult respiratory diseases syndrome, shock, fibrosis, pulmonary hypersensitivity, allergic rhinitis, atopic dermatitis, psoriasis, weight control, rheumatoid arthritis, cachexia, Crohn's disease, ulcerative colitis, arthritic conditions and other inflammatory diseases, depression, multi-infarct dementia and AIDS in a mammal, including a human, comprising an amount of a compound of the formula I or a pharmaceutically acceptable salt thereof, effective in such treatment and a pharmaceutically acceptable carrier.
The present invention also relates to a method for the treatment of respiratory, allergic, rheumatoid, body weight regulation, inflammatory and central nervous system disorders such as asthma, chronic obstructive pulmonary disease, adult respiratory diseases syndrome, shock, fibrosis, pulmonary hypersensitivity, allergic rhinitis, atopic dermatitis, psoriasis, weight control, rheumatoid arthritis, cachexia, Crohn's disease, ulcerative colitis, arthritic conditions and other inflammatory diseases, depression, multi-infarct dementia and AIDS in a mammal, including a human, comprising administering to said mammal an amount of a compound of the formula I or a pharmaceutically acceptable salt thereof, effective in such treatment.
DETAILED DESCRIPTION OF THE INVENTION
The following reaction Schemes illustrate the preparation of compounds of the present invention. Unless otherwise indicated a, b, X, R 1 , R 2 , R 3 , R 4 and R 5 in the reaction Schemes and the discussion that follow are defined as above.
In reaction 1 of Scheme 1, the benzenesulfonyl chloride compound of formula III is converted to the corresponding cyano compound of formula IV by in situ reduction of III to the corresponding sulfinate salt followed by reaction with a haloacetonitrile, preferably bromoacetonitrile. The reaction mixture so formed is heated at a temperature between about 50° C. to about 70° C, preferably about 60° C., for a time period between about 1 hour to about 3 hours, preferably about 2 hours.
In reaction 2 of Scheme 1, the compound of formula IV is converted to the corresponding pyrazineacetonitrile compound of formula V by reacting IV with a 2,3-dichloropyrazine compound of formula
in the presence of potassium carbonate and a polar aprotic solvent, such as dimethylformamide. The reaction mixture is heated at a temperature between about 70° C. to about 90° C., preferably about 80° C., for a time period between about 6 hours to about 8 hours, preferably about 7 hours.
In reaction 3 of Scheme 1, the pyrazineacetonitrile compound of formula V is converted to the corresponding 5-arylsulfonyl-imidazo[1′,2′:1,6]pyrido[2,3-6]pyrazine-6-amine compound of formula I by reacting V with a 1-methylimidazole, when X is CH, or a 1-methyl-1,2,4-triazole, when X is N, in a polar aprotic solvent, such as dimethylformamide. The reaction mixture so formed is heated to a temperature of about 140° C. to about 180° C., preferably 160° C., for a time period between about 1 hour to about 8 hours, preferably about 6 hours.
In reaction 1 of Scheme 2, the compound of formula IV is converted to the corresponding benzopyrazineacetonitrile compound of formula VI by reacting IV with a dichlorobenzopyrazine compound of the formula
in the presence of potassium carbonate and a polar apotic solvent, such as dimethylformamide. The reaction mixture is heated at a temperature between about 70° C. to about 90° C., preferably about 80° C., for a time period between about 6 hours to about 8 hours, preferably about 7 hours.
In reaction 2 of Scheme 2, the compound of formula VI is converted to the corresponding compound of formula II according to the procedure described above in reaction 3 of Scheme 1.
The compounds of formula I that are basic in nature are capable of forming a wide variety of different salts with various inorganic and organic acids. Although such salts must be pharmaceutically acceptable for administration to humans or animals, it is often desirable in practice to initially isolate the compound of formula I from the reaction mixture as a pharmaceutically unacceptable salt and then simply convert the latter back to the free base compound by treatment with an alkaline reagent and subsequently convert the latter free base to a pharmaceutically acceptable acid addition salt. The acid addition salts of the base compounds of this invention are readily prepared by treating the base compound with a substantially equivalent amount of the chosen mineral or organic acid in an aqueous solvent medium or in a suitable organic solvent, such as methanol or ethanol. Upon evaporation of the solvent, the desired solid salt is readily obtained. The desired acid addition salt can also be precipitated from a solution of the free base in an organic solvent by adding to the solution an appropriate mineral or organic acid. Pharmaceutically acceptable salts of amino groups include hydrochloride, hydrobromide, sulfate, hydrogen sulfate, phosphate, hydrogen phosphate, dihydrogen phosphate, acetate, succinate, citrate, tartrate, lactate, mandelate, methanesulfonate (mesylate) and p-toluenesulfonate (tosylate) salts. Cationic salts of the compounds of formula I are similarly prepared except through reaction of a carboxy group with an appropriate cationic salt reagent such as sodium, potassium, calcium, magnesium, ammonium, N,N′-dibenzyiethylenediamine, N-methylglucamine (meglumine), ethanolamine, tromethamine, or diethanolamine.
Those compounds of the present invention that are acidic in nature are capable of forming base salts with various pharmacologically acceptable cations. Examples of such salts include the alkali metal or alkaline-earth metal salts and particularly, the sodium and potassium salts. These salts are all prepared by conventional techniques. The chemical bases which are used as reagents to prepare the pharmaceutically acceptable base salts of this invention are those which form non-toxic base salts with the acidic compounds of the present invention. Such non-toxic base salts include those derived from such pharmacologically acceptable cations as sodium, potassium calcium and magnesium, etc. These salts can easily be prepared by treating the corresponding acidic compounds with an aqueous solution containing the desired pharmacologically acceptable cations, and then evaporating the resulting solution to dryness, preferably under reduced pressure. Alternatively, they may also be prepared by mixing lower alkanolic solutions of the acidic compounds and the desired alkali metal alkoxide together, and then evaporating the resulting solution to dryness in the same manner as before. In either case, stoichiometric quantities of reagents are preferably employed in order to ensure completeness of reaction and maximum yields of the desired final product.
For administration to humans in the curative or prophylactic treatment of inflammatory diseases, oral dosages of a compound of formula I or a pharmaceutically acceptable salt thereof (the active compounds) are generally in the range of 0.1 to 1000 mg daily, in single or divided doses, for an average adult patient (70 kg). The active compounds can be administered in single or divided doses. Individual tablets or capsules should generally contain from 0.1 to 100 mg of active compound, in a suitable pharmaceutically acceptable vehicle or carrier. Dosages for intravenous administration are typically within the range of 0.1 to 10 mg per single dose as required. For intranasal or inhaler administration, the dosage is generally formulated as a 0.1 to 1% (w/v) solution. In practice the physician will determine the actual dosage which will be most suitable for an individual patient and it will vary with the age, weight and response of the particular patient. The above dosages are exemplary of the average case but there can, of course, be individual instances where higher or lower dosage ranges are merited, and all such dosages are within the scope of this invention.
For human use, the active compounds of the present invention can be administered alone, but will generally be administered in an admixture with a pharmaceutical diluent or carrier selected with regard to the intended route of administration and standard pharmaceutical practice. For example, they may be administered orally in the form of tablets containing such excipients as starch or lactose, or in capsules either alone or in admixture with excipients, or in the form of elixirs or suspensions containing flavoring or coloring agents. They may be injected parenterally; for example, intravenously, intramuscularly or subcutaneously. For parenteral administration, they are best used in the form of a sterile aqueous solution which may contain other substances; for example, enough salts or glucose to make the solution isotonic.
Additionally, the active compounds may be administered topically when treating inflammatory conditions of the skin and this may be done by way of creams, jellies, gels, pastes, and ointments, in accordance with standard pharmaceutical practice.
The therapeutic compounds may also be administered to a mammal other than a human. The dosage to be administered to a mammal will depend on the animal species and the disease or disorder being treated. The therapeutic compounds may be administered to animals in the form of a capsule, bolus, tablet or liquid drench. The therapeutic compounds may also be administered to animals by injection or as an implant. Such formulations are prepared in a conventional manner in accordance with standard veterinary practice. As an alternative the therapeutic compounds may be administered with the animal feedstuff and for this purpose a concentrated feed additive or premix may be prepared for mixing with the normal animal feed.
The ability of the compounds of formula I or the pharmaceutically acceptable salts thereof to inhibit PDE 4 may be determined by the following assay.
Inhibition of PDE4 Isozymes
Preparation of Test Compounds
Compounds are dissolved in dimethyl sulfoxide at a concentration of 1×10 −2 M, or to a desired higher concentration if solubility is an issue then diluted 1:25 in water (4×10 −4 M compound, 4% DMSO). Further serial dilutions are made in 4% dimethyl sulfoxide to achieve desired concentrations. Final dimethyl sulfoxide concentration in assay is 1%.
In duplicate, the following are added in order to a scintillation vial (all concentrations are given as final concentrations in vial).
25 μl compound of dimethyl sulfoxide (1%, for blank)
25 μl [ 3 H] cAMP-containing assay buffer (1 μM [ 3 H] cAMP, 50 mM Tris, 10 mM MgCl 2 , pH 7.5)
25 μl 5′-nucleotidase (0.001 unit) (Sigma #N5880)
25 μl PDE4 isozyme (1/1200-1/2400 dilution in Prep #1)
The reaction vials are shaken and placed in a water bath (3.7° C.) for 30 minutes, at which time the reaction is stopped by adding 1 ml Dowex 1×8 resin, chloride form (1:3 slurry in distilled water). Three ml Ready Safte scintillation fluid are added directly to each vial. Mix each vial well and count radioactivity after resin has settled (approx. 4 hours at room temperature).
Data Calculation and Interpretation
Percent inhibition is determined by the formula: % inh = 1 - avg . cpm ( test compound ) - avg . cpm ( blank ) avg . cpm ( control ( no compound ) - avg . cpm ( blank ) × 100
IC50 is defined as that concentration of compound which inhibits 50% of radioactivity, and is determined by Microsoft Excel or other appropriate software.
The present invention is illustrated by the following examples, but is not limited to the details thereof.
Preparation 1
[(4-Ethylphenyl)sulfonyl]-acetonitrile
In a 125 mL, three-necked flask fiited with thermometer, addition funnel, and glass stopper was placed 11.5 grams (91.2 mmol) of sodium sulfite, 8.32 grams (97.7 mmol) of sodium bicarbonate, and 50 mL of water. After heating the mixture to 75-80° C., 10.0 grams (48.9 mmol) of 4-ethylbenzenesulfonyl chloride was added dropwise over 0.5 hours. When the addition was complete, heating was continued for 3 hours at which time a white precipitate formed. The suspension was cooled to room temperature and allowed to stir for 16 hours. The precipitate was collected by filtration, washed with cold water, combined with a second crop from the filtrate, and dried under high vaccum to give 13.9 grams (>100% yield) of crude sodium 4-ethylbenzenesulfinate.
In a small Parr bottle was placed the salt above, 3.09 mL (5.33 grams, 44.9 mmol) of bromoacetonitrile, and 0.488 grams of aliquat™-336. The contents were agitated on a Vortex-2 Genie™ for 5 minutes using a spatula to maintain homogeneity. The bottle was transferred to an oil bath and heated for 2 hours at 60° C., as the mixture softened, turned pink-orange, and then hardened. The solid was extracted with 250 mL of ethyl acetate, filtered, and evaporated to a solid. Trituration in methylene chloride gave 5.61 grams (55% yield) of the title compound as an off-white solid. Melting Point: 120-121° C. Anal. Calcd for C 10 H 11 NO 2 S: C, 54.40; H, 5.30; N, 6.69. Found: C, 57.29; H, 5.39; N, 6.6.1.
Preparations 2-4
The compounds of Preparations 2-4 were prepared according to the procedure of Preparation 1 substituting the indicated sulfonyl chloride for 4-ethylbenzenesulfonyl chloride.
Prep-
aration
R 3
M.P. (° C.)
C, H, N Analysis
2
CH(CH 3 ) 2
64-66
Calcd for C 11 H 13 NO 2 S: C, 59.17; H,
5.87; N, 6.27. Found: C, 59.31; H,
5.82; N, 6.27.
3
n-C 3 H 7
123-134
Calcd for C 11 H 13 NO 2 S: C, 59.17; H,
5.87; N, 6.27. Found: C, 59.42; H,
5.82; N, 6.23.
4
OCH 3
115-117
Calcd for C 9 H 9 NO 3 S: C, 51.12; H,
4.29; N, 6.63. Found: C, 51.27; H,
4.16; N, 6.63.
Preparation 5
3-Chloro-□-[(4-methylphenyl)sulfonyl]2-pyrazineacetonitrile
A mixture of 6.38 grams (32.7 mmol) of (4-methylbenzenesulfonyl)acetonitrile (for preparation, see: Bram, G. et al., Synthesis, 1987, 56), 4.87 grams (32.7 mmol) of 2,3-dichloropyrazine, 4.97 grams (36.0 mmol) of potassium carbonate, and 10 mL of dimethylformamide was heated for 7 hours at 80° C. The solvent was removed by vaccum distillation, and the residue was diluted with 100 mL of aqueous 1 N hydrochloric acid solution and extracted with ethyl acetate (1×150 mL, 1×100 mL). The combined extracts were washed with brine (1×100 mL), dried (magnesium sulfate) and evaporated to give 8.9 grams of a dark oil. Purification by flash chromatography using a 30-50% ethyl acetate-hexane eluant gave 2.35 grams of solid which was triturated in ether to afford 2.20 grams (20% yield) of the title compound as a white solid. Melting Point: 148-151° C. (lit. 126° C. (Litvinenko, S. V. et al., Chem. Heterocycl. Compd. (Eng. Transl.), 1992, 28, 93)). Anal. Calcd for C 13 H 10 N 3 O 2 CIS: C, 50.74; H, 3.28; N, 13.65. Found: C, 50.45; H, 3.53; N, 13.77.
Preparations 6-9
The compounds of Preparations 6-9 were prepared according to the procedure of Preparation 5 substituting the indicated substrate for (4-methylbenzenesulfonyl)acetonitrile.
Preparation
R 3
Substrate
M.P. (° C.)
C, H, N Analysis
6
C 2 H 5
Compound
129-131
Calcd for C 14 H 12 N 3 O 2 ClS: C, 52.26; H,
of Pep. 1
3.76; N, 13.06. Found: C, 52.38; H,
3.59; N, 12.97.
7
CH(CH 3 ) 2
Compound
88-94
Calcd for C 15 H 14 N 3 O 2 ClS: C, 53.49; H,
of Prep. 2
4.49; N, 12.48. Found: C, 53.72; H,
4.21; N, 12.47.
8
n-C 3 H 7
Compound
100-103
Calcd for C 15 H 14 N 3 O 2 ClS: C, 53.49; H,
of Prep. 3
4.49; N, 12.48. Found: C, 53.70; H,
4.31; N, 12.34.
9
OCH 3
Compound
135-136
Calcd for C 13 H 10 N 3 O 3 ClS: C, 48.23; H,
of Prep. 4
3.11; N, 12.98. Found: C, 48.42; H,
3.15; N, 12.86.
Preparation 10
3-Chloro-□-[(4-ethylphenyl)sulfonyl]-2-quinoxalineacetonitrile
The title compound was prepared as a tan powder, melting point 208-211° C., according to the procedure of Preparation 5 substituting the compound of Preparation 1 for (4-methylbenzesulfonyl)acetonitrile and substituting 2,3-dichlorquinazoline for 2,3-dichloropyrazine. Calcd for C 18 H 14 N 3 O 2 SCI: C, 58.14 H, 3.79; N, 11.30. Found: C, 58.15; H, 3.59; N, 11.32.
EXAMPLE 1
5-[(4-Methylphenyl)sulfonyl]-imidazo[1′,2′:1,6]pyrido[2,3-b]pyrazin-6-amine
A mixture of 360 mg (1.17 mmol) of the compound of Preparation 5, 0.280 mL (288 mg, 3.51 mmol) of 1-methylimidiazole, and 2 mL of dimethylformamide was heated for 1.5 hours at 160° C. An additional 0.280 mL of 1-methylimidazole was added and heating was continued for 4.5 hours. The solvent and excess 1-methylimidazole was removed by distillation under high vaccum, and the dark solid residue was extracted with 150 mL of boiling toluene and filtered. The filtrate was evaporated to give 234 mg of a dark solid brown solid. The insoluble material from the hot toluene extract was extracted with 100 mL of boiling chloroform, filtered, and evaporated to give 214 mg of a dark brown solid. Both solids were purified separately by flash chromatography using 5% acetone-chloroform as eluant, and the enriched fractions from each purification were combined and evaporated to give 301 mg of a yellow solid. Trituration in ether followed by rercrystallization from toluene afforded 148 mg (37% yield) of the title compound as a fluffy yellow solid. Melting Point: 294-295° C. Anal. Calcd for C 16 H 13 N 5 O 2 S: C, 56.63; H, 3.86; N, 20.64. Found: C, 56.87; H, 3.79; N, 20.61.
EXAMPLES 2-6
The compounds of Examples 2-6 were prepared according to the procedure of Example 1 substituting the indicated substrate for the compound of Preparation 5 and, in the case of Example 2, substituting 1-methyl-1,2,4-triazole for 1-methylimidazole. In some cases, reactions were performed neat in excess 1-methylimidazole or 1-methyl-1,2,4-triazole.
Example
R 3
X
Substrate
M.P. (° C.)
Spectral or Analytical Data
2
CH 3
N
Compound
>300° C.
Anal. Calcd for C 15 H 12 N 6 O 2 S: C, 52.93;
of Prep. 5
H, 3.55; N, 24.69. Found: C, 53.31; H,
3.55; N, 24.68.
3
CH 2 CH 3
CH
Compound
267.5-268.5
Anal. Calcd for C 17 H 15 N 5 O 2 S: C, 57.78;
of Prep. 6
H, 4.28; N, 19.82. Found: C, 57.88; H,
4.24; N, 19.77.
4
CH(CH 3 ) 2
CH
Compound
241-244
Anal. Calcd for C 18 H 17 N 5 O 2 S: C, 58.84;
of Prep. 7
H, 4.66; N, 19.06. Found: C, 58.63; H,
4.55; N, 18.88.
5
n-C 3 H 7
CH
Compound
231-232
1 H NMR(DMSO-d 6 )d 0.84(3H, t, J=7
of Prep. 8
Hz), 1.49-1.61(2H, m), 2.58(2H, t, J=
7.5Hz), 7.35(2H, d, J=8Hz), 7.74(1
H, d, J=1Hz), 7.99(2H, d, J=8Hz),
8.05(1H, br s), 8.26(1H, br s), 8.34(1
H, d, J=2.5Hz), 8.54(1H, d, J=1Hz),
8.57(1H, d, J=2.5Hz).
6
OCH 3
CH
Compound
269-270
1 H NMR(DMSO-d 6 )d 3.77(3H, s), 7.01
of Prep. 9
(2H, d, J=8Hz), 7.71-7.72(1H, m),
7.98(1H, br s), 8.00(2H, d, J=8Hz),
8.21(1H, br s), 8.32-8.33(1H, m), 8.51-
8.52(1H, m), 8.555-8.563(1H, m).
EXAMPLE 7
5-[(4-Ethylphenyl)sulfonyl]-[1,2,4]triazolo[4′,3′:1,6]pyrido[2,3-b]quinoxalin-4-amine
The title compound was prepared as a fluffy yellow solid, melting point>300° C., according to the procedure Example 1 substituting the compound of Preparation 10 for the compound of Preparation 5 and substituting 1-methyl-1,2,4-triazole for 1-methylimidazole. Calcd for C 15 H 16 N 6 O 2 S: C, 59.39; H, 3.99; N, 20.78. Found: C, 59.33; H, 3.99; N, 21.10.
EXAMPLE 8
5-[(4-Hydroxyphenyl)sulfonyl]-imidazo[1′,2′:1,6]pyrido[2,3-b]pyrazin-6-amine
A mixture of 97 mg (0.27 mmol) of the compound of Example 6, 360 mg (2.7 mmol) of lithium iodide, and 5 mL of collidine was heated for 4 hours at 210° C. The solvent was removed by distillation under vaccum, and the residue was taken up in 100 mL of ethyl acetate, washed with saturated aqueous sodium sulfate solution (1×25 mL), aqueous 1 N hydrochloric acid solution (1×100 mL), water (1×100 mL), saturated aqueous sodium sulfate solution (1×50 mL), and brine (1×50 mL). Solids were removed by filtration, and the filtrate was dried (magnesium sulfate) and evaporated to give 110 mg of a solid which was triturated in hot methanol to afford 90 mg (95% yield) of the title compound as a bright yellow solid. Melting Point: >300° C. AMPI MS (m/e) 341 (M + ). | This application is directed to a compound of Formula I
wherein a, X, R 1 , R 2 , R 3 and R 4 are as defined herein, useful in the treatment of respiratory, allergic, rheumatoid, body weight regulation, inflammatory and central nervous system disorders such as asthma, chronic obstructive pulmonary disease, adult respiratory diseases syndrome, shock, fibrosis, pulmonary hypersensitivity, allergic rhinitis, atopic dermatitis, psoriasis, weight control, rheumatoid arthritis, cachexia, Crohn's disease, ulcerative colitis, arthritic conditions and other inflammatory diseases, depression, multi-infarct dementia and AIDS. | 2 |
FIELD OF THE INVENTION
The invention relates to a device for the elimination of dirt from a fibre fleece rotating on a toothed roller, namely by means of a static but adjustable separation surface arranged opposite to the radial direction of the toothed roller and, seen in the direction of rotation of the toothed roller, an introduced preparatory element likewise static but adjustable in the radial direction of the toothed roller, whereby a separation gap remains free between the preparatory element and the separation surface.
BACKGROUND
In the present state of technology the devices previously mentioned are known, for example, from GB-PS 1,058,894, in which dirt is sucked out and carried away by means of a suction channel from the fleece lying on the main cylinder after the passage of the revolving flat by means of a knife arranged opposite to the direction of rotation of the main cylinder. A fleece guiding deflector is introduced to the knife, seen in the direction of rotation of the main cylinder.
An improved embodiment of the previously mentioned device for the elimination of dirt, also called briefly "dirt separator", is shown in DE-3,034,036 C2 (equivalent to U.S. Pat. No. 4,400,852) in which an additional saw toothed clothing is provided directly after the knife, in order to lay the fibre layer on the main cylinder so that the fibres are again laid parallel after they had been brought into a certain random layer by the suction.
A further dirt separator is shown in U.S. Pat. No. 4,309,796, in which the guide plate introduced to the knife is subsequently arranged seen in the direction of rotation of the main cylinder and a static carding element is provided directly after the knife. The whole is shown in a carding machine in which only static carding elements are used and a dirt separator previously mentioned is provided between these static elements, respectively.
A similar embodiment is shown in DE-2,846,109 C3 (equivalent to U.S. Pat. No. 4,314,387) in which, likewise after a static carding element, (seen in the direction of rotation of the main cylinder) a guide plate is provided opposite to the surface of the main cylinder as well as a knife which forms a specified separation gap and which is fastened on the subsequent static carding element.
Thereby the guide surface is part of a collecting rail which is adjustable away from and against the main cylinder surface, as also applies to the guide knife.
Moreover, the latter elements are still adjustable in such a way that the clearance of the separation gap between the edge of the knife and the collecting rail is alterable.
The general disadvantage of the previously mentioned state of technology can be observed in the opening room and card room from the viewpoint of the development of the throughput performance of modern machines, in that the performance in these areas has considerably increased in latter years.
In particular, not only higher throughput performances are demanded from the cards, but also an improved carded sliver, so that development work must be undertaken in the systematics of the individual carding functions in order to obtain a more even carded sliver with higher performance, which, moreover, has less neps, dirt content and less damage to the fibers.
In the previously mentioned state of technology it can be established without exception that the inventors at this stage of technological development were of the opinion that, before reaching the edge of the knife previously mentioned, the fibre fleece lying on the main cylinder must be guided through a smooth guide surface, in order to obtain good results. This consideration emanated from the experience that a dirt separator gap between two static card elements without the guide surface previously mentioned shows a so-called "snout" in the separation gap which had the disadvantage that this snout, if uncontrolled, could reach either the suction or the fleece. This "snout-effect" could be eliminated with the previously mentioned guide plate introduced to the knife.
In the high performances demanded from such a card at the present time, it is, however, necessary not to have any surfaces on the main cylinder which do not have a carding function, if possible.
For this reason, the task is to find a substitute for the previously mentioned guide plate which has at least a positive carding result without the so-called snout effect.
Experiments have now surprisingly shown that a card rod turned through 180°, which is inserted instead of the previously mentioned guide surface, still gave a good carding result whilst guiding the fibres to the knife without the appearance of a snout.
For this reason, the invention solving this problem goes therefore, in the direction that the state of technology previously mentioned has attached the criterion that the preparatory element should have a structured surface opposite to the periphery of the toothed roller.
SUMMARY OF THE INVENTION
In accordance with the invention, a device is provided for the separation of dirt from a fibre fleece on a rotating toothed roller. The device includes a separation knife arranged opposite to a direction of rotation of the toothed roller so that it is static but adjustable in the radial direction of the toothed roller. A preparatory element upstream of the separation knife with respect to the direction of rotation of the toothed roller is also static but adjustable in the radial direction of the toothed roller. A separation gap remains free between the preparatory element and the separation knife and the preparatory element has a structured surface opposite to the periphery of the toothed roller.
In accordance with a preferred embodiment of the invention, the separation gap is covered by a suction channel. Also, the preparatory element can be a card rod with the structured surface of the card rod being formed by an all steel clothing with teeth arranged in the direction of movement of the periphery of the toothed roller. The all steel clothing can have a front rake of 0° to 75°. The structured surface can be a fish scale surface with the fish scales arranged in the direction of movement of the periphery of the toothed roller or the structured surface can be a ribbed surface, the ribs of which are transverse to the direction of movement of the periphery of the toothed roller and which extend over the whole length of the card rod. The structured surface can also be a knurled surface or an undulating surface with undulations arranged transversely to the direction of movement of the periphery of the toothed roller and which extend over the whole surface of the card rod. Alternatively, the structured surface can be provided with rows of neighboring dimples which cover the entire surface or the structured surface can be covered with wart like protuberances.
In another preferred embodiment, the structured surface can be formed by an orifice plate and the card rod can have a hollow space, the orifice plate covering the hollow space of the card rod on a side facing the periphery of the toothed roller. The orifice plate can have a specified number of holes which connect the hollow space with the surroundings of the structured surface and the diameter of the holes can be between 0.3 mm and 1.5 mm. The hollow space can be connected to an underpressure source or an excess pressure source and a pulsator can be provided between the pressure sources and the hollow space to permit the air in the hollow space to pulsate.
The preparatory element can be arranged to be adjustable in the radial direction of the toothed roller and the separating knife can be arranged to be adjustable in the radial direction of the toothed roller. The card rod can be provided subsequent to the knife, seen in the direction of movement of the toothed roller, whereby on the one hand the card rod is adjustable in the radial direction of the toothed roller and on the other hand, the knife can be adjusted on the card rod in such a way that the knife edge can be adjusted towards or away from the periphery of the toothed roller. The preparatory element can also be adjustable in the peripheral direction of the toothed roller in order to alter the opening of the separation gap.
The advantages achieved through the invention lie in the fact that with the optimal layout of the card for carding results, it is possible to separate dirt optimally at the same time.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is explained in more detail with reference to the accompanying drawings, in which:
FIG. 1 shows a transverse section through a card, limited to a representation only of those parts which refer to the invention, schematically represented;
FIG. 2 shows an enlarged representation of the section of the card from FIG. 1;
FIG. 3 shows a variant of the device of FIG. 2;
FIG. 3a shows an enlargement of part of the device shown in FIG. 2;
FIGS. 4-6, 8, 9, 11 and 13 each show a variant of an element shown in FIG. 2;
FIGS. 7, 10 and 12 each show a view of FIGS. 6, 9, 11, respectively, from a direction III;
FIG. 14 shows a variant of the device of FIG. 3;
FIG. 15 shows an application of the element of FIG. 11 in a cross section taken along the arrow I of FIG. 16;
FIG. 16 shows a topview of FIG. 15;
FIG. 17 shows an embodiment for adjusting the elements of FIGS. 1-16;
FIG. 18 shows a topview of part of FIG. 17, according to the direction of the arrow II;
FIG. 19 shows a detail of FIGS. 2, 3 and 14 in section and in an enlarged representation; and
FIG. 20 shows a variant of an element of FIG. 2.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows schematically the transverse section of a card 1 with a main cylinder 2, a revolving flat 3 arranged above, a licker-in 4 and a doffer roll 5. The elements in front of the licker-in and after the doffer roll are not shown for the sake of simplicity.
In the after carding zone between the revolving flat 3 and the doffer roll 5 as well as in the precarding zone between the doffer roll 5 and the licker-in 4, a preparatory element 6, a suction device 7 and a separating knife 8 are provided respectively one after each other, seen in the direction of rotation D of the main cylinder. This combination corresponds with the combination shown in FIG. 2.
In the precarding zone between the licker-in 4 and the revolving flat 3 a combination is provided according to FIG. 3, namely, in sequence, a preparatory element 6, a suction device 7 and a separating knife 9. Thereby the separating knife is arranged to be adjustable on a carding element 10 in the direction of the arrow 11.
In the precarding zone there is a carding element 12 arranged in front of the preparatory element 6 and after the carding element 10, whilst in the after carding zone and in the precarding zone carding elements 12 are provided after the separating knife 8, namely one in the after carding zone and five in the precarding zone.
Thereby, with the carding elements 12, this is a matter of the same carding elements as the carding elements 10, however, without the separating knife 9.
The manner in which the elements 6, 8, 10 and 12 are fastened is explained later with the aid of FIG. 17. It should only be pointed out in the interim that the elements 6, 8, 10 and 12, respectively, are arranged to be adjustable in the direction of the arrow 13, that is, these elements are installed to be adjustable, in the radial direction against and away from the main cylinder 2.
Further, the elements 8 and 10 are also adjustable in the direction of the arrow 14, and likewise explained and shown with the aid of FIGS. 17 and 18.
Moreover, in FIGS. 2 and 3, there is in addition an all steel clothing 15 belonging to the main cylinder 2, drawn on to the surface of this, which is schematically represented.
The preparatory element 6 consists of a carrier body 16 arranged together with an all steel clothing 17. The manner in which such all steel clothing is arranged on such carrier bodies 16 is well known from the state of technology, for example from the Swiss patent specification 543 607, and is therefore not further described.
The inventive idea of the all steel clothing 17 of the preparatory element 6 lies in the fact that the teeth of this clothing are arranged with edges thereof facing substantially in the direction of movement D of the main cylinder and that the front rake alpha (α) (see FIG. 3a) is in the range from 0 to 75 degrees. Thereby, the term front rake is defined in the DIN Standard Sheet No. 64 123/ Sheet 1.
The separating knife 8 has a similar form to the carrier body 16 of the preparatory element 6 but it has, however, a cutting edge 18 directed against the direction of movement D of the main cylinder 2 and a smooth bottom face 22.
A separation gap 19 remains open between the cutting edge 18 and the all steel clothing 17.
The dirt separated through this cutting gap 19 is taken up from the suction device 7 and conveyed to a filter (not shown).
The suction device 7 consists of a U-shaped channel 20, described later, which lies on the preparatory element 6 and on the separating knife 8, respectively, by means of foam rubber gaskets 21, without exercising any force in the actual sense. Thereby, the foam rubber can be glued to the channel 20.
FIG. 3 shows partly the same elements as FIG. 2 which is the reason why the same elements are designated with the same reference symbols and are not described once more.
FIG. 3 shows an advantageous embodiment over FIG. 2 insofar as instead of the separating knife 8, a relatively smaller separating knife 9 is provided on the carding element 10. Instead of the bottom face 22 of the separating knife 8, a card clothing 23 (also called an all steel clothing) can be provided so that the length of the bottom face 22 (seen in the direction of movement D) can substantially be used for carding. This all steel clothing 23 is a normal card clothing, that is, it does not have a type of tooth as the steel clothing 17. The functions of the card clothing are known and are not further described for this reason.
The manner of fastening the separation knife 9 on the carding element 10 is not shown further. It can, however, either be held firmly to the carding element 10 or be movable and locked in position in the direction of movement 11 by means of a guide slot and screws fitted to it, which are anchored in the carding element 10.
For operation, the preparatory element 6 and the carding element 10 must each be adjustable separately in the direction of movement 13, 14 respectively. This adjustment is not impeded by the foam rubber gasket 21 of the suction device 7, as the adjustment is kept within a very small range.
FIGS. 4, 5 and 8 each show a preparatory element 6, having an alternative to the all steel clothing 17. For example, FIG. 4 shows the structured surface as fish scales 24 having edges thereof facing the direction of rotation of the main cylinder instead of the all steel clothing 17, whilst FIG. 5 shows longitudinal ribs 25 and FIG. 8 shows longitudinal undulations 26.
The terms "longitudinal ribs" or "longitudinal undulations" are understood to mean those ribs or undulations, respectively, stretching over the entire length of the preparatory elements 6 so that they correspond at least in their length to the width of the main cylinder 2, or its clothing, respectively, which for the specialist is taken to refer to the width of the main cylinder.
The technical and technological function of the all steel clothing 17, the fish scales 24, the ribs 25 and undulations 26, respectively, as well as the further variants, still to be described in the following, consist of setting the unevenness of the fleece lying on the all steel clothing 15 of the main cylinder in vibration, in order to bring the particles of dirt better to the surface with the aid of centrifugal force, which also works on the particles of dirt in the fleece, in order to separate them on the knife edge 18 and remove them by means of the suction device 17.
Moreover, a positive carding result still exists even though reduced, when compared with normal card clothing.
As further variants for the fulfillment of the technical and technological purposes, FIGS. 6 and 7 show instead of the all steel clothing 17, a knurled surface 27, whilst FIGS. 9 and 10 are provided with crater shaped depressions 28 and FIG. 13 with wart-like protuberances 29.
FIGS. 11 and 12 show a further step in the realization of the inventive idea, in that the preparatory element 6.1 is provided with a hollow space 30, which has a connecting opening 31 and an orifice plate 32 on one side.
The dimensions of the teeth of the all steel clothing 17, of the fish scales 24, of the ribs 25, the undulations 26, of the knurling 27, the dimples or depressions 28 and protuberances 29, respectively, and of the hole diameter and number of holes 33 of the orifice plate 32 are to be determined by experiments and are not further explained here. As a guiding principle, a hole diameter between 0.3 and 1.5 mm can be used.
FIG. 14 shows a variant of the device from FIG. 3 in that a knife 34 is arranged on the carding element 10 and in the direction of movement 35 is arranged so that it can be movable or be locked in position.
The movement or locked setting of the knife 34 is effected with the aid of an adjusting screw 37, which is connected with the knife 34 by means of its screw thread, rotating in a support 36 but which, however, is locked in position against axial displacement.
The support 36 is rigidly connected with the carding element 10 with screws 38.
The suction device 7.1 includes a channel 20.1 and has the same function as the suction device 7 which includes the channel 20. The latter is, however, sealed against the atmosphere in the area of the knife 34 by means of a lip seal 75 adjacent to the knife 34 and firmly glued to the channel 20, 20.1.
Regarding the independent movement of the knife 34, relative to the mobility of the carding element 10 and relative to the mobility of the preparatory element 6, what has already been said for the suction device 7 still applies, namely that the movements are very small and are not affected by the seals 21 and 75.
FIGS. 15 and 16 show an application of the preparatory element 6.1 from FIGS. 11 and 12 with a plurality of connection openings 31, all of which are connected with an air collection pipe 39 over the connection supports 40.
The air collection pipe on its part is connected either with an excess pressure air source 41 or with an underpressure source 42.
Further, the air collection pipe 39 is provided with a rotating shut off flap 43 which is connected with the driving shaft of a driving motor 44.
The function of this rotating shut off flap 43 consists of the production of an under pressure or excess pressure air stream in the air collection pipe. It is only used when this pulsating air has an application.
The shut off flap 43 can remain in the open position if the occasion arises when the pulsating air is not in use.
The function of the pulsating air, whether it is underpressure or excess pressure, consists of the vibration of the fleece lying on the clothing of the main cylinder 15, as already explained, before this reaches the knife edge 18 of the knife edges of the knives 9 or 34, respectively.
Whichever of the two processes is used, whether it is underpressure or excess pressure, depends on the technological requirements on the card and can be decided from case to case.
The term "air collection pipe" is in itself not really descriptive of an underpressure operation, as in such cases it acts more as an air distribution pipe. For the sake of simplicity, the same term is used for both types of processes.
FIG. 17 corresponds substantially to FIG. 1 of German Patent Application DE-3,811,679.0 which is mentioned in order to show the anchoring of the elements 6, 8, 10 and 12 with regard to mobility in the radial direction of movement 13. Details of this anchoring arrangement are also shown in copending and commonly owned U.S. patent application Ser. No. 07/424,505 filed on Oct. 20, 1989, the disclosure of which is hereby incorporated by reference.
FIG. 18 does not correspond to the previously mentioned German patent application, but rather, is an additional variant of that application, in order to arrange that the elements 8 and 10 so as to also be movable in the peripheral direction 14. FIG. 17 shows some details of the card 1, in order to explain the adjustable fastening of the elements 6, 8, 10 and 12.
As can be seen from FIGS. 1 and 17, there is a card 1 consisting of a main cylinder 2, which is pivotable on an axis 45 so that it can be driven, a casing 46, which covers the front ends of the main cylinder, whereby only the left part of the casing on the left front face of the main cylinder in FIG. 17 is visible. Movable elements in the radial direction of the main cylinder surround the card and, as already explained, these are the preparatory element 6, the knife 8 or the carding element 10 as well as the carding element 12. All of these elements can, for example, be fastened so that they are adjustable in the way shown with the aid of the FIG. 17. It should be understood that the invention is not restricted to this type of fastening.
The revolving flat 3 additionally shown in FIG. 1, the licker-in 4, and the doffer roll 5 are not important to the present invention and are not further described for this reason.
The main cylinder 2 carries an all steel clothing 47 in the customary manner.
The elements 6, 8, 10, and 12 are formed on the ends in the same way, which is the reason why they can all be fastened in the way shown in FIG. 17. This manner of fastening is described more closely in the following:
As shown in FIG. 17, the casing 46 has a rigidly arranged flange 48, which is a component part of the casing and extends as an annulus around the axis 45 of the main cylinder. A fastening block 49 is fastened to the flange 48 by screws 50 extending in the radial direction. Each of the elements 6, 8, 10 or 12 is held against the fastening block 49 by means of a spring clip 51. The support of the two ends of the elements 6, 8, 10 or 12, is effected over the fastening block 49 and an adjustment block 52, the upper part of which is led into a guide extending in the radial direction in the ends of the elements 6, 8, 10 or 12. There is an adjusting screw 53 with a screw thread 54 above the adjustment block 52, which works in conjunction with the corresponding screw thread 55 in the end of the cover. The end 56 of the adjusting screw 53 opposite to the manipulating head engages with the radial outer flange 57 of the adjustment block 52 and in this way supports the end of the elements 6, 8, 10 or 12, whereby the desired radial clearance to the spiked clothing of the main cylinder can be set by turning the screw 53.
A clamping screw 58 extends at a right angle to the adjustment screw 53, that is, parallel to the axis of the main cylinder and engages with its thread 59 in a corresponding internal thread 60 in the adjusting block 52. A washer 61 is located below the operating head 62 of the clamping screw 58, so that this is drawn against the outer wall part 63 of the end of one of the elements 6, 8, 10 and 12 and tightened with the clamping screw 58 of the adjusting block 52. Through this, the set clearance of the clothing 17, 23 or of their alternatives 24, 25, 26, 27, 28, 29 is fixed.
The spring clip 51 has a first limb 64 and a second limb 65 bent from a spring steel strip, whereby the limb 65 forms an angle of 80° with the first limb. The first limb 64 has an angled part 66 which is fastened to the fastening block 49 via a screw 67. The angled part 66 of the spring clip also has a slot 68 (FIG. 18) which is provided for fitting guide pins 69 in order to determine the correct position of the spring clip on the fastening block 49 against twisting in the peripheral direction of the main cylinder.
On the other hand, when the screw is slack, this slot permits the spring clip 51 and therewith the appropriate ends of the elements 6, 8, 10 and 12 to move in the direction of movement 14 (FIGS. 2, 3 and 18), in order to alter the width of the opening of the separation gap 19.
The second limb 65 likewise has an angled part 70 on the end opposite to the first limb, which is fork shaped. The two dovetails 71, 72 (only one of which is shown in FIG. 17) of the fork shaped part 70 extend along both sides of a stiffening rib 73 of the elements 6, 8, 10 or 12, shown in the installed state in FIG. 17, whereby the edge 74 of the fork shaped opening presses on the upper side of the stiffening rib 73.
FIG. 19 shows the fastening system of FIG. 17, however, for the fastening of the U-shaped channel 20. For this purpose a connecting piece 76 is arranged rigidly on a front end closing wall 77 of the channel 20, the cross section of which corresponds to the cross section of the stiffening rib 73.
Reference is also made to DE-3,811,679 for the system from FIGS. 17 and 20. It can be likewise explained that the system used on both ends of the elements 6, 8, 10, 12 or the channel 20 is a mirror image.
It should however be explained that the application of the inventive idea is not restricted to the type of the adjustment and fastening of the elements 6, 8, 10 or 12 shown in FIG. 17 and FIG. 19. Other types of fastening and adjustment, which permit a movement of the elements in the directions 13, 14, respectively, should be regarded as equivalents.
Moreover, it is shown in FIG. 20 that the elements 6 in FIGS. 2 to 10 and 13 can be combined with element 6.1 as element 6.2 which has a hollow space and can be used with the system according to FIGS. 15 and 16. For this purpose holes (not shown) must be provided for the passage of air between the individual items of all the steel clothing 17 or in the ribs 25 or in the wave troughs or undulations 26 or in the craters 28, respectively, adjacent to the dimpling or protuberances 29 or in the troughs of the knurled surface 27. Thereby, the number and diameter of the holes must be determined through experiments.
Finally, it should be explained that the invention is not restricted to the application in a card, rather, it can likewise be used on all rollers which carry a fleece from which dirt must be eliminated. | A card including a main cylinder, a revolving flat as well as a licker-in roller and a doffing roller (also called a doffer roll) also includes a suction device in combination with a separating knife in order to improve the carding result and eliminate dirt in the precarding zone between the licker-in and the revolving flat, in the after carding zone between the revolving flat and the doffer roll as well as in the precarding zone between the doffer roll and the licker-in. A preparatory element has a structured surface arranged opposite to the surface of the main cylinder, in which the teeth are arranged facing the direction of rotation of the main cylinder. This structured surface allows the carding result to be retained and subjects the fleece lying on the main cylinder to a certain vibration so that, in combination with centrifugal force and the separating knife, there is better dirt separation which can be removed through the suction device. The precarding zone between the licker-in and the revolving flat can include a knife which differs from the knife in the after carding and precarding zone, in that it is not an independent element, but rather, is assigned to a card rod. With this arrangement, the carding result should be improved and the elimination of dirt on a card should also be improved. The arrangement can also be applied to all rollers carrying a fleece in which dirt must be eliminated from the fleece. | 3 |
TECHNICAL FIELD
The present disclosure is related to power sources and in particular to switching mode power supplies comprising buck type regulators
BACKGROUND
A switching mode power supply (SMPS) converts power from a source, for instance Vdd, on an integrated circuit chip into a voltage or current to be used to power a portion of the circuits on that integrated circuit chip. Switching mode power supplies comprise buck, boost and buck-boost power converters. The buck converter stores energy into an inductor and provides an output voltage that is a result of the reluctance of the inductor to change current flowing in the inductor. The boost converter stores energy into an inductor and provides an output greater than source voltage and the buck-boost converter produces an output that is either higher or lower than the source voltage.
The buck power converter generates a pulse width modulated (PWM) switching voltage at the LX node shown in FIG. 1 , which is then filtered by an inductor L 1 . Generally, buck converters operate in one of two modes, PWM mode at a fixed frequency, or pulse frequency modulation (PFM) mode where the frequency is allowed to change with load current.
Typically the PFM mode is used for low-power operation and can be highly efficient. In the PFM mode, the PMOS transistor P 1 is typically turned on when the output voltage falls below a low threshold. The PMOS transistor is then turned off when the current in the inductor rises above a fixed limit, or if the output voltage rises above an upper threshold. When the PMOS transistor P 1 is turned off the current in the inductor L 1 continues to flow, until the inductor is discharged. This current must be supplied from ground. This can be done using a diode, but the voltage drop across the diode reduces the efficiency of the buck converter. Therefore, most high efficiency buck converters use an NMOS transistor N 1 , directly controlled by the buck control circuitry, and when the PMOS transistor P 1 turns off, the NMOS transistor N 1 is turned on.
If the load is low, the buck may only need to switch to at a low frequency to supply the output current. If the NMOS transistor is left on until the PMOS transistor is triggered again, the current in the inductor will go negative, the NMOS transistor will end up discharging the output of the buck converter and power will be wasted. Instead the NMOS transistor is turned off once the current in the inductor reaches zero current, which is typically referred to as an active diode behavior. In one common implementation of a buck converter, the active diode function is implemented by measuring the voltage across the NMOS transistor. If the voltage at the LX node is negative, the current is still positive, and the NMOS transistor is kept on. But once the voltage at the LX node goes above ground, the NMOS transistor is turned off.
US 2006/0279970 A1 (Kernahan) is directed to control system and method for simultaneously regulating the operation of a plurality of different types of switching power regulators including not having the regulator feeding current back to the supply. U.S. Pat. No. 8,222,879 B2 (Nguyan) is directed to a circuit that includes a buck voltage regulator couple to an active current modulator, which is operative to detect negative current in the low side switch of the voltage regulator. In U.S. Pat. No. 7,443,699 B2 (Lhermite) is directed to a power supply controller that uses a negative current of a power transistor to detect a point for enabling the power transistor when driving an inductor. In U.S. Pat. No. 7,365,661 B2 (Thomas) a control system and method is directed to simultaneously regulating the operation of a plurality of different types of switching power converters. In U.S. Pat. No. 7,095,220 B2 (Kernahan) a method is directed to controlling an operation of a switching power converter which includes a first and second series connected transistors and including the handling of “negative” current flow. U.S. Pat. No. 6,911,809 B2 (Kernahan) is directed to a controller configured to control the pulse widths of a plurality of pulse width modulated switching power supplies, wherein a discontinuous operation, current is not fed back to the supply from the inductor.
SUMMARY
It is an objective of the present disclosure to control the NMOS transistor to permit “negative” current to pass in the event that the output voltage rises too high.
It is also an objective of the present disclosure to vary the amount of “negative” current that may pass through the NMOS transistor in proportion to the error of the output voltage.
It is further an objective of the present disclosure to establish a small offset to prevent normal output ripple from causing the NMOS transistor from passing “negative” current.
The buck power regulator of the present disclosure is formed by a PMOS transistor and an NMOS transistor connected together between Vdd and circuit ground or Vss. A node LX is formed at the connection between the NMOS and PMOS transistors. The LX node is also connected to an inductor L 1 , which is coupled to the output of the buck power regulator, and to a zero crossing comparator, which in turn is connected to one input of an AND circuit that drives the gate of the NMOS transistor, or active diode. The other input to the AND circuit is connected to the gate of the PMOS transistor, which provides input current to the inductor.
The zero crossing comparator monitors the voltage across the NMOS transistor, and when the voltage goes from negative to positive, the current flowing through the NMOS transistor has changed direction from a current flowing from ground into the inductor to a current flowing from the inductor into ground, called “negative current”. The zero crossing comparator senses the change in voltage across the NMOS transistor, which signifies a change in the direction of current flow, and turns off the NMOS transistor. Since the positive input of the zero crossing comparator is connected to ground and the negative input is connected to the LX node, the voltage across the NMOS transistor will be negative as measured by the zero crossing comparator when current is flowing from circuit ground through the comparator into the LX node and therefore into the inductor.
The term “negative current” is used to describe the direction of current flow through the NMOS transistor, wherein the NMOS transistor is also known as an active diode. The NMOS transistor is designated as an active diode because under ideal situation the NMOS is turned off when current from circuit ground flowing into the buck power regulator ends. Thus the NMOS transistor is controlled operate similar to a diode.
In the present disclosure a comparator, or an amplifier, with an input connected to the target voltage of the buck power regulator and a feedback voltage from the output of the buck power regulator is used to provide the positive input to the zero crossing comparator. When the amplifier is used instead of the comparator, a continuously varying active diode threshold is applied to the NMOS transistor, which governs the amount of “negative current” that is allowed to pass from the inductor to circuit ground and discharges a higher overvoltage with a higher “negative current”
BRIEF DESCRIPTION OF THE DRAWINGS
This invention will be described with reference to the accompanying drawings, wherein:
FIG. 1 is a circuit diagram of the basic buck power regulator of prior art;
FIG. 2 is a diagram of the clock and the inductor current in a PWM (pulse width modulation) buck power regulator of the present disclosure;
FIG. 3 is a diagram of the output voltage and inductor current in a PFM (pulse frequency modulation) buck power regulator of the present disclosure;
FIG. 4 is a diagram of a zero crossing monitoring circuit of the NMOS trasnsistor of the buck power regulator of the present disclosure;
FIG. 5 is circuit a diagram that allows excess current in the bunch power regulator to be discharged to ground before the NMOS transistor is turned off; and
FIG. 6 is a signal diagram of the present disclosure that shows the build up of current in the inductor when output voltage is larger than the target voltage,
DETAILED DESCRIPTION
In FIG. 2 is shown the clock that is applied to input signal of the PMOS transistor of the buck power regulator operating in PWM (pulse width modulation) mode of the present disclosure and the resulting inductor current. When there is a clock pulse, the PMOS transistor conducts and supplies a current (raising current signal) to the inductor of the buck power regulator. When the clock pulse is terminated, the NMOS transistor is turned on and current continues to flow (falling current signal) into the inductor from ground until the current stored in the inductor is depleted, at which time the NMOS transistor is turned off to prevent excess current to flow into the inductor from circuit ground. If there is no load on the power regulator the current as shown in the I inductor diagram will vary around ground.
In FIG. 3 is shown the output voltage and inductor current for a buck power regulator operating in PFM (pulse frequency modulated) mode. In the PFM mode the output goes into high impedance mode once the PMOS transistor of the buck regulator has delivered an amount of charge to the output. Both the PMOS and NMOS transistors remain off until the load has discharged the load to the threshold that is required for the PMOS transistor to be turned on again. When the PMOS transistor is turned on, an amount of current is delivered by the PMOS transistor to the Inductor as demonstrated in the rise in inductor current. The current into the inductor continues to flow once the PMOS transistor turns off through the NMOS transistor turns as demonstrated in the fall of the inductor current. Since the buck regulator operating in the PFM mode does not pass “negative current” and only switches when required, a high efficiency can be achieved at low output currents while operating in the PFM mode.
The key disadvantage of this system is that the buck regulator cannot discharge its output if for any reason the output goes into overvoltage. This leads to complex control systems that require a PWM mode for high loads and for dynamically changing output voltages, but then switching to PFM for low load conditions. These schemes require sensing systems to decide which mode to operate in. There is therefore a large benefit to any system that can fully regulate in PFM mode.
In FIG. 4 is shown circuitry to monitor and prevent “negative current” flowing from the output of the buck power regulator to circuit ground. This is accomplished by detecting when the voltage across the NMOS transistor reverses polarity, which signifies a reversal in direction of current flow to current flowing from the buck regulator to circuit ground, called “negative current”. The NMOS transistor is turned off by the AND circuit 42 when a zero crossing is detected. When the direction of current flow in the NMOS transistor changes direction, the voltage across the NMOS also changes polarity. Detecting this change in voltage polarity is accomplished by the zero crossing detector 41 in which the negative input terminal of the detector is connected to the LX node and the positive input terminal is connected to circuit ground. The output of the zero crossing detector is coupled to one input of an AND circuit 42 , wherein the second input to the AND circuit 42 is coupled to the input of the PMOS transistor. Thus when the PMOS is not being driven by a signal and a voltage change across the NMOS transistor is detected by the zero crossing detector 41 , the NMOS transistor is turned off.
In FIG. 5 a comparator 43 compares the output voltage, Vout, of the buck regulator to the input voltage, Vtarget. Vtarget is usually established by a DAC, but any analog voltage source can be used to provide a target for the output voltage of the buck regulator. The output of the comparator 43 causes a voltage drop across the R 1 resistor 44 that is connected to the positive input of the zero crossing comparator 41 . This compares the voltage at the LX node to another voltage instead of circuit ground shown in FIG. 4 , and the current at which the NMOS transistor turns off can be varied.
When the output of the zero crossing comparator switches voltage polarity, the current in the NMOS transistor has switched from current flowing from circuit ground (Vss) into the buck regulator to current flowing from the buck regulator into circuit ground (called negative current) and the NMOS transistor is turned off by the AND circuit 42 . Thus excess charge builds up on the output of the buck regulator circuit with no place to discharge the stored charge from the regulator. A combining circuit 43 taking the form of a comparator, compares the output voltage to the input voltage and creates a current that flows through resistor R 1 43 that allows the threshold of zero crossing comparator 41 to raise an amount to permit some of the excess current that has built up in the buck regulator to be conducted each cycle by the NMOS transistor to Vss, or circuit ground. If each time the NMOS transistor is turned on a small amount of excess current is bled away efficiency of the buck regulator is reduced. This inefficiency can be somewhat negated by implementing a small dead zone so that a small error at the buck regulator output does not cause an offset to be added to the active diode threshold. An alternative to the combining circuit being a comparator circuit is for the combining circuit to be an amplifier, wherein the amount of current that can be discharged to circuit ground is proportional to the amount of overvoltage present at the output of the regulator. In either case, the combining circuit using, either a comparator or an amplifier, provides a mechanism to discharge excess current to circuit ground.
In FIG. 6 is shown the build up of current in the inductor, I inductor. When Vtarget is larger than Vout, the triangular shaped current pulses are formed by the inductor current, first as the PMOS transistor conducts current (raising waveform) from Vdd into the inductor L 1 and then as the NMOS transistor continues to conduct current (falling waveform) into the inductor from circuit ground, Vss. Then there is no current until the next time the PMOS transistor is turned on in the next cycle. When an overvoltage is detected, Vout becomes higher than Vtarget, and the inductor L 1 conducts excess current from the inductor to Vss, called “negative current”. If the NMOS transistor becomes an active diode and is turned off when zero crossing is detected, then the output voltage will continue to rise and the excess charge in the regulator will not be discharged without the operation of the comparator 43 shown in FIG. 5 . Vout becomes larger than Vtarget and is compared together in comparator 43 , which produces a current through resistor R 1 that forms a voltage drop that is coupled to the positive input to the zero crossing comparator. Thus the voltage at node LX (across the NMOS transistor) is allowed to raise by the amount of voltage across R 1 and the NMOS transistor is kept on a little longer to discharge some of the excess current in the inductor to circuit ground. If the comparator 43 is an amplifier instead, then the active diode formed by the NMOS transistor and the zero crossing circuitry will have a continuously varying threshold voltage to discharge excess current from the buck regulator and bring the output voltage back in line with the target voltage.
It should be noted that it is within the scope of the present disclosure to use a fixed voltage offset, including circuit ground (zero volts), to replace the operations and results of the circuitry related to the combining circuit shown in FIG. 5 . It is also within the scope of the present disclosure that the fixed voltage offset, including circuit ground, can be switched on or off as needed to discharge excess current to circuit ground.
While the invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made without departing from the spirit and scope of the invention. | An active diode formed within a buck power regulator with an NMOS transistor is connected to a PMOS transistor at a node that is further connected to the regulator output through an inductor. The active diode combines the NMOS transistor with circuitry to prevent conduction once the active diode passes a threshold voltage. Additional circuitry compares the output voltage to the target input voltage and varies the threshold voltage of the active diode such that the active diode can discharge excess current from the regulator each cycle until the output voltage is less than the target voltage. | 8 |
BACKROUND OF THE INVENTION
The invention relates to testing devices, and more particularly to devices for testing high-pressure lamps and electrical components used to energize them.
High-pressure sodium lamps are now used in outdoor luminaire fixtures. Such lamps are not operated directly from the power supplied to the fixture; a ballast and a starting aid circuit (hereinafter "starting aid") are required to make the lamp work. Furthermore, fixtures of this type may be wired to include a photocell which responds to ambient light and automatically turns the lamp on and off at sunset and sunrise.
Each of these components can fail and a failed component cannot normally be identified using visual examination alone. Such identification requires electrical testing.
When a lineman repairs an outdoor luminaire fixture of the type described, he normally tends to change the lamp, photocell and starting aid until the sysetm works properly. This repair method entails the substantial likelihood that nondefective parts will be taken out and subsequently discarded as defective.
It would be advantageous to provide a device to facilitate the testing of the various electrical parts used in, e.g. high-pressure sodium outdoor luminaire fixtures, so that defective parts could be separated from working ones.
It is one object of the invention to provide a device for conveniently testing high-pressure lamps and components used with them.
It is another object of the invention to provide a device which can be used to test the efficiency of various high-pressure lamp systems.
It is still another object to provide a device which is suitable for use by a lineman to test a wide variety of different components used in high-pressure lamp systems.
It is a further object to generally improve over the prior art.
In accordance with the invention, there is provided a means for testing and energizing a tank circuit of the type which is used in an electrical supply for a high-pressure lamp. There is also provided a means for testing and energizing a ballast of this type. There is further provided a means for testing and energizing a starting aid circuit of this type. There is further provided a means for measuring a voltage across a high-pressure lamp under test, and a means for enabling operation of this measuring means after energization of a starting aid circuit.
In accordance with the invention, components under test are connected, in a suitable high-pressure lamp circuit, to other components which are known to work. The effect of the component under test on the operation of the circuit establishes whether the component is operable or not. Because normal operation of the starting aid can damage a conventional voltmeter circuit such as is needed to test the lamp, operation of this circuit takes place only after such damage cannot occur.
In a preferred embodiment, there is also provided means for disabling the measuring means in response to detection of particular fault conditions. This prevents the device from being burned out by a faulty part under test.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood with reference to the following illusrative and non-limiting drawings, in which:
FIG. 1 is a schematic diagram of a high-pressure sodium lamp circuit;
FIG. 2 shows the impedences of the circuit of FIG. 1 before the lamp becomes conductive;
FIG. 3 shows the impedences of the circuit of FIG. 1 after the lamp becomes conductive;
FIG. 4 is a schematic diagram of one section of a preferred embodiment; and
FIG. 5 is a schematic diagram of another section of the preferred embodiment.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
A conventional high-pressure sodium lamp circuit will be explained with reference to FIG. 1. Power is supplied by an AC source 2. One side of the source 2 is connected to one end of a ballast 4; the other side of the source 2 is grounded. A high-pressure sodium lamp 6 is connected between the other end of the ballast 4 and ground. An electronic starting aid 8 is connected across the lamp 6 and is connected to the tap of the ballast 4. A tank circuit 10 which includes a resistor 12 in parallel with a capacitor 14 is connected across the source 2.
The lamp 6 creates light by an arc struck between its electrodes (not shown). Such an arc cannot be created unless the lamp 6 has been ionized. Thus, when the lamp 6 is nonconductive, the impedances of the circuit shown in FIG. 1 are represented by the schematic equivalent circuit shown in FIG. 2; the impedance of the tank circuit 10 is Z 4 , the impedance of the ballast 4 is Z 1 , the impedance of the starting aid 8 is Z 2 , and the impedance Z 3 of the lamp 6 is infinite.
When the lamp system is turned on by closure of switch 16 (which may correspond to a photocell under test as described below) the starting aid 8 produces high voltage (perhaps 2500-4000 V) and high frequency (perhaps 0.25 MHz) pulses for a predetermined time (perhaps 2 seconds). This ionizes the lamp 6 and reduces its impedance to perhaps 48-52 ohms. The lamp 6 then becomes conductive and produces light. Since the impedance of the starting aid 8 is extremely high (on the order of megohms) relative to the low impedance of the lamp 6, the starting aid 8 is essentially out of the circuit (as is shown in FIG. 3).
Because the impedance of the lamp 6 changes so rapidly, it is necessary to limit the voltage across the lamp 6 to prevent it from burning out. This is the function of the ballast 4. As schematically shown, the ballast 4 is a tapped coil wrapped around a flux-conducting core, but the ballast 4 may alternately be an electronic circuit or some other voltage limiting device. The construction of the ballast 4 is not part of the invention.
The purpose of the tank circuit 10 is to optimize the steady-state impedance match between the source 2 and the ballast 4 and lamp 6. Changing the value of the resistor 12 changes the power factor of the lamp 6; changing the value of the capacitor 14 changes the efficiency of the lamp 6.
A preferred embodiment of the invention has two sections, which are shown separately in FIGS. 4 and 5. FIG. 4 shows the section which tests components for use on 120 VAC; FIG. 5 shows the section which tests components for use on 240 VAC. These voltages are not part of the invention; they have been chosen to correspond to standard voltages used in systems of this type.
The operation of these two sections is conceptually identical. Therefore, the operation of the preferred embodiment will be explained only with reference to FIG. 4, except where the two sections differ. To facilitate understanding of the correspondance between the two sections, their corresponding parts are identified by corresponding reference numerals.
The preferred embodiment forms a circuit which is the electrical equivalent of a high-pressure sodium lamp circuit. Testing is carried out by connecting in circuit with standard components the components under test, and interpreting the readings of the pilot lights and meters hereinafter described. A power switch 18 turns the test circuit on and off. A fuse 20 is in series with the switch 18. After the fuse 20 is connected a pilot light 22 which lights up when power has been turned on. In this example, the pilot light 22 is in series with a resistor 24, but this is not part of the invention.
A standard photocell socket 26 is connected after the fuse 20. This socket has three electrodes: 28, 30, and 32. Power is supplied to a tested photocell through electrodes 28 and 30, and electrode 32 is supposed to be conductive or nonconductive depending on ambient light. To test a standard photocell, an ammeter 34 is connected to electrode 30; the ammeter 34 shows the relay loading current for the photocell (not shown).
A switch 36 is connected to the electrode 32. After the switch 36 is connected a voltmeter 38, which is in parallel with a pilot light 40. (Light 40 is in series with a resistor 44, but this is not part of the invention.) With switch 36 closed and a working photocell under test, the light 40 will turn on and off when the photocell window is covered and uncovered; the voltmeter 38 quantifies the operation of the photocell contacts. Once the operation of the photocell has been checked, a dummy plug (not shown) can be put into the socket 26, and the ammeter 34 shunted by a switch 42. Alternatively, a working photocell under test can be left in place with its window covered.
After the switch 36, there is connected a wattmeter 46. The wattmeter 46 measures the power consumed by the rest of the circuitry, permitting verification of lamp circuit specifications.
After the wattmeter 46, there are connected in series two ammeters 48 and 50. The ammeters 48 and 50 are provided to permit calculation of the high power factor improvement of the tank circuit discussed below. This will be explained later.
A tank circuit is connected between ground and the common junction point of the ammeters 48 and 50. This tank circuit has two parallel branches; in one branch there can be a resistor 52 and in the other a capacitor 54. These components are connected through e.g. banana jacks 56. If testing of other components is to be carried out using the standard resistor 52 and the capacitor 54, the jacks 56 are connected so that these two components are in circuit; if another resistor and/or capacitor is to be tested instead, the resistor 52 and/or the capacitor 54 are disconnected and and replaced by the components under test.
After this tank circuit, there is connected a ballast selector and indicator circuit generally indicated by circuit block 58. This ballast selector and indicator circuit 58 has the function of permitting the selection of one of three circuit branches for use with the lamp under test and identifying for the user the branch so selected. Each of these branches may be connected (using appropriate connectors) to contain either a standard ballast or a ballast to be tested. (The ballasts may be coils or circuits; their construction is not part of the invention.)
Three standard ballasts 60, 62 and 64 are provided. Ballast 60 is a 70 watt ballast, ballast 62 is a 100 watt ballast, and ballast 64 is a 150 watt ballast. Each ballast is connected via appropriate connectors 66, so a ballast under test may be substituted for a standard ballast.
Two switches 68 and 70 connect the tap and end of the ballast 60 to circuit points 72 and 74 respectively. Two switches 76 and 78 connect the tap and end of the ballast 62 to circuit points 72 and 74 respectively. Two switches 80 and 82 connect the tap and end of the ballast 64 to circuit points 72 and 74 respectively.
The switches 68 and 70 are ganged together, and are also ganged to a switch 84. The switch 84 is placed in series with a resistor 86 and a pilot light 88. Since the switches 68, 70 and 84 are all opened and closed together, when the ballast 60 is placed in circuit (or when a ballast under test is substituted for the ballast 60 and likewise placed in circuit) the pilot light 88 lights up, indicating which of the ballasts 60, 62 and 64 has been selected. The same holds true for the switches 76, 78, and 90; when these three switches are closed, the ballast 62 or its substitute is placed in circuit and current flows through a resistor 94 to light a pilot light 96. Switches 80, 82, and 98 work in the same way to light a pilot light 102 when the ballast 64 or its substitute has been placed in circuit.
If desired, the switches 68, 70, 84, 76, 78, 90, 80, 82 and 98 may be ganged together in a multiple position rotary switch. It is also possible to use electronic switching circuitry to accomplish the results described above.
A standard 150 watt starting aid 104 is connected as by appropriate connectors 106 to circuit point 72, circuit point 74, and ground. The starting aid 104 has a voltage which can be set between 2500 volts and 4000 volts, a frequency of about 0.25 MHz, and an ionizing voltage time of about 2 seconds. The starting aid 104 can be used to test other components, or can be replaced by a starting aid under test.
A standard mogul-type high-pressure sodium lamp socket 108 is connected across circuit point 72 and ground through a switch 110. This socket 108 receives a high-pressure sodium lamp (not shown) for testing.
Before the operation of the remaining parts shown in FIG. 4 is discussed, circuit operation using a normal tank circuit, ballast, and starting aid will be described. (The switch 110 is assumed to be closed, a working photocell with its window covered or a dummy photocell is assumed to be in the socket 26, and the switch 51 which connects the tank circuit is assumed to be closed.) When the switch 36 is closed, current flows through the voltmeter 38 and the pilot light 40. This indicates that the photocell is working. Current is supplied to the resistor 52 and the capacitor 54 in the tank circuit, one of the ballasts 60, 62 or 64, and to the starting aid 104.
The starting aid 104 produces high-voltage, high-frequency pulses between circuit point 72 and ground for about 2 seconds. This ionizes the lamp in socket 108 and causes current to begin to flow in it. The current through the lamp rapidly increases and the starting aid stops producing ionizing pulses, and the voltage at circuit point 72 drops to approximately 52-55 volts. The reading of the wattmeter 46 then represents the power used by the system, the reading of the ammeter 48 then represents the current used by the system, and the reading of the ammeter 50 then represents the current flowing through the lamp and the ballast. Since the reading of the ammeter 48 will always be greater than the reading of the ammeter 50, the difference between the two permits the efficiency of the tank circuit to be calculated.
A voltmeter 112 is in series with a contact set 114 and both are in parallel with the socket 108. The purpose of the voltmeter 112 is to moniter the voltage across a lamp under test. If the voltmeter 112 were connected directly across the socket 108, the high-voltage pulses produced by the starting aid 104 during the ionization phase of the lamp would burn the voltmeter 112 out. Therefore, the contact set 114 is closed only after the ionization phase of the starting aid 104 is over.
This is accomplished by the use of a timer 116, which is connected after the switch 36 through a normally closed contact set 118 described in more detail below. The timer 116 controls two contact sets: contact set 114 and and contact set 120 (described below).
The timer 116 is adjusted to close the contact sets 114 and 120 approximately 5 seconds after the switch 36 is closed. This insures that the voltmeter 112 is not connected across the lamp under test until after the starting aid 104 has finished its ionization phase.
An alarm such as a buzzer 122 may be connected in parallel with the voltmeter 112. When the voltage across a lamp under test is too high, this indicates either a defective lamp or a defective starting aid. The overvoltage condition will be reflected in a high reading of the voltmeter 112, and if the buzzer 122 is provided the overvoltage condition will be also be indicated by an audio indication. The buzzer 122 is chosen such that only overvoltage conditions have sufficient voltage to make it produce an audio alarm.
The pilot light 124, resistor 126, switch 128 and switch 110 are provided to isolate a defective starting aid under certain circumstances. If a lamp under test does not light up, the voltage across it should be low. The pilot light 124 and resistor 126 are chosen such that if there is enough voltage across a lamp under test to light the pilot light 124, the starting aid is defective. For this purpose, switches 110 and 128 are ganged together so that when the switch 110 is closed, the switch 128 is open and vice versa. The switches 110 and 128 are thrown between 2 and 4 seconds after the switch 36 is closed, if the lamp under test fails to light.
A voltmeter 130 is placed across the three branches in the ballast selector and indicator circuit 58. This is for the purpose of monitering the voltage across the ballast during a test.
Under certain circumstances, the voltage between circuit point 72 and ground will always exceed the rating of the voltmeter 112. Under these circumstances, the voltage at circuit point 74 will likewise be excessive.
To prevent the voltmeter 112 from being burned out under these circumstances, there is provided a relay having a coil 132, which operates the contact set 118. The coil 132 is connected in series with a potentiometer 134 and the contact set 120, so that these three components are connected between circuit point 74 and ground.
Contact set 118 is normally closed. Thus, after closure of the switch 36, the timer 116 starts the 5 second delay period and subsequently closes the contact sets 114 and 120. If the voltage at circuit point 74 is excessive, there is sufficient voltage through the coil 132 to open the contact set 118, to disable the timer 116, and to open the contact sets 114 and 120 before any damage occurs to the voltmeter 112. The potentiometer 134 is provided to adjust the voltage at which the contact set 118 opens.
In FIG. 5, there is provided a transformer 136. Both ends of the secondary winding of the transformer 136 are fused with fuses 138. The transformer 136 steps up the 120 VAC primary supply to 240 VAC for testing 240 VAC lamps and components. All the components to the right of the transformer 136 in FIG. 5 are chosen to operate at this voltage; the starting aid 104' is rated up to 400 watts. There are only two branches in the ballast selector and indicator circuit 58' because standard ballasts for 240 VAC come in 200 watt (ballast 60') and 400 watt (ballast 62') versions. However, in neither the ballast selector and indicator circuit 58 nor the ballast selector and indicator circuit 58' is the number of branches a part of the invention; there can be any number of branches depending on the number of models of ballasts and lamps which are to be tested.
The meters may be either of the analog or of the digital type; the type of meter used is not part of the invention. It is likewise unnecessary to the invention that there be two sections, or that the sections use, e.g., different timers, wattmeters, etc.
Although a preferred embodiment has been described above, the scope of the invention is limited only by the following claims, | A circuit for testing high-pressure lamps and components used therewith includes standard components which form a conventional high-pressure lamp circuit. The components can be replaced by components under test. Circuits are provided to prevent damage to the device as a result of malfunctions or of normal operation of the components. Provisions are made for measuring efficiency of various lamp systems. | 6 |
FIELD OF THE INVENTION
The present invention relates to a system and a method for archiving and supplying documents using a central archive system.
BACKGROUND OF THE INVENTION
Conventional archive systems are generally closed systems. Closed systems of this kind have interfaces for importing documents and searching for them. Links with other archive systems are confined to the intake of documents plus index data. As a result, the administrative and configuring tools available within the archive systems are purely system-related.
Where there is only one archive system being used within a company, the facilities offered by the system are generally adequate. The administrators have only one system to look after and the users are familiar with the end-user interface. In practice, however, it has been found that in companies of any size there is generally more than one archiving solution in use.
Where there is more than one archiving solution in use, possibly on different platforms, it becomes increasingly difficult for the company to administer all the systems, to obtain an overview of the document holdings which exist within the company, and to provide end-users with easy access to these documents. The last point is a particular problem because, where there are several systems, the end-user has to know how to operate all of them.
A natural development of individual archive systems is a central archive system that can incorporate other archive systems irrespective of their platforms and producers. The advantage of a central archive system is that, because it will fully incorporate a large number of individual archive systems, it gives a complete picture of the document holdings which exist within a company. A system which can be cited as an example of a central archive system which provides this facility for incorporation is the Enterprise Document Management System (EDMS), commercially available from IBM Corporation. The essential features of a central archive system that can incorporate different individual archive systems are:
1. A central index to many different document management systems and decentralized servers, irrespective of the platforms they use.
2. Ability to process large volumes of data.
3. Harmonized view of all documents irrespective of where they are stored.
4. Total flexibility of indexing and thus total flexibility for search enquiries and document requests as well.
Where a central archive is going to be used, it has to be embedded into the existing infrastructure of a company. This is particularly true of end-user applications (end-user interfaces), which can differ widely from company to company or even from division to division within a company. Rigidly fixed search facilities in the form of hard-wired search applications and search windows which exist in some conventional archiving systems do not simply restrict the widespread adoption of central archives but in fact virtually rule out their use in practice. To provide the maximum possible flexibility, it would be necessary to have interfaces which, as far as their functionality is concerned, provide every possible facility for search and document requesting applications which matched to the company's needs. Since central archives are usually only employed in companies where there are a very large number of people using them, an interface of this kind needs to be a server component which accepts search/document requests from users as clients and passes them on to the central archive for processing, as shown in FIG. 1 .
An interface of this kind, which will be referred to herein as a front-end server, should also be available for as many platforms as possible. Where there is a front-end server of this kind (as there is in EDMS), then it can be used by the company to handle accesses to the central archive from company-specific user interfaces.
FIG. 2 shows a central archive to which external archiving systems are connected. The index of the documents present in the external archiving systems is stored in the central archive. Special access programs tailored to the external archiving systems enable the document requests made to be handled by the central archive.
A company-specific search application adapted to the front-end server is used by an end-user to make searches in the central archive. The search request is accepted by the front-end server and passed on to the central archive for processing. The central archive makes the search and passes the result back to the front-end server, from where it can be collected by the company-specific application. The end-user selects the documents he needs to look at and asks the central archive for them. The latter finds that the relevant documents are in an external archiving system and in turn asks the external system for them. Once they reach the central archive, the central archive passes the documents on to the front-end server, from where they can be collected by the company-specific application.
Document-request handling of this kind can be seen as a basic function of central archives. The disadvantages it has are that:
a) By reference to the data held in store, the central archive must recognize that the document requests it has are for documents whose index is stored in the central archive but which are themselves stored in an external archiving system.
b) The central archive must contain data on where a document request has to be passed on to or which triggers a request to the external archiving system in question.
c) The central archive must accept documents supplied by external archiving systems and pass them on to the front-end server.
d) For each external archiving system, the central archive must have a program for handling document requests or a program of this kind must be implemented to connect in the external systems.
SUMMARY OF THE INVENTION
Generally, a method and apparatus are disclosed for archiving and supplying documents using a central archive. If it is assumed that the individual external archiving systems belonging to a company were procured before the central archive system, then for each external archiving system the company will already have a mechanism for directly handling document requests. According to an aspect of the invention, once a list of the results of a search has been supplied, then the central archive can be bypassed and the particular external archiving system involved can be accessed directly.
The object of the present invention is therefore to provide a simplified method and system for supplying documents by using a central archive, which method and system avoids the disadvantages mentioned above.
The present invention relates to flexible facilities for supplying documents where the index to the documents is stored in a central archive but the documents themselves are stored in an external archiving system.
The solution according to the invention is based on management of the addresses in the external archiving systems which is performed at the central archive. The approach adopted supports the specifying of any desired number of backup servers and, by allowing the configurable supply either of the address relation itself and/or of server address information attached to the list of search results, it provides a facility which supports the full range of document supply capabilities available when a central archive is being used.
A more complete understanding of the present invention, as well as further features and advantages of the present invention, will be obtained by reference to the following detailed description and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention is described below by reference to a preferred embodiment shown in the drawings, in which
FIG. 1 shows the prior art supply of documents from a central archive system;
FIG. 2 shows the supply of documents from an external archiving system via the central archive;
FIG. 3 shows the central archive architecture according to the invention for supplying documents; and
FIG. 4 shows the central archive architecture according to the invention for supplying documents when an address catalogue is used.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
FIG. 1 illustrates the existing method of supplying documents via a central archive system. The user makes a search enquiry to the central archive system from his own system. The user system is not connected directly to the central archive but is connected via a server system. Documents can either be stored in the central archive system itself or they may be located on an external archiving system, in which case all that is stored on the central archive system is index information to enable the documents to be accessed. Index information comprises identifiers which help to find a given document. If for example contracts and agreements of all kinds are stored on an external archiving system, then the following identifiers for accessing the contracts and agreements may exist on the central archive system: purchase agreement, car purchase agreement, name of purchaser, make of car, date of purchase agreement, number of purchase agreement and so on. The values making up a particular identifier need not specifically identify a single document, e.g., the identifier “Name” will generally identify a plurality of documents. If the user makes a search request by selecting one or more identifiers, the documents shown in the list of search results will be those which contain these identifiers. In FIG. 1, three documents were found and the user is requesting document 3 from the central archive.
FIG. 2 shows the prior art communications architecture between the user, the central archive system and external archiving systems. The central archive system has access to external archiving systems A-N and there are a plurality of applications which communicate with the central archive system. An application sends a search enquiry to the central archive system. The central archive system sends to the application a list of search results comprising the index data for documents A 1 , B 5 , Nn. The user sends to the central archive system a request for a selected document to be supplied. The central archive system identifies the server on which document A 1 is stored from the address data and sends a request to the server which has been identified (external archiving system A) for document A 1 to be supplied. Document A 1 is then sent to the application via the central archive system.
FIG. 3 shows the central archive architecture according to the present invention for supplying documents.
The method to which the present invention relates is based on administration and management, supported by the central archive system, of the external archiving systems linked to the central archive system.
At the time of the index import, i.e., when index data is loaded into the central archive system, a logic address in the external archive system in which the particular document is physically stored is at the same time loaded into the index for the document which is stored on the central archive system. These logic addresses are managed as 1-N relations within the central archive system, i.e., one logic address is assigned to a plurality of real addresses, with one element being marked out as CURRENT. A 1-N relation of this kind ensures that
a) any desired number of backup servers can be defined for each external archiving system;
b) when an archiving system is moved, the real address can be changed without any problems.
To obtain the maximum possible flexibility for company-specific applications, in the present invention the component of the central archive system which is responsible for supplying lists of search results is designed to be configurable. Possible options are:
1. Supply of the real address plus x backup addresses (when defined) by the central archive system. When lists of search results are supplied, the component responsible for this task converts the logic address into the real address (plus backup addresses) which is current at that time, assigns it to the address meta-information and supplies it to the front-end server (external interface with central archive system). The risk inherent in supplying data of this kind is that of the real address being changed by an administrator shortly after a list of search results is supplied. This is a risk particularly with front-end servers which have a disconnected retrieval function (e.g., mobile users put in document requests on day x but do not retrieve the results until day x+y). The address meta-information has to be read out by the application and a direct connection then made with the external archiving system. The desired document is supplied direct to the user without being diverted through the central archive system.
2. Supply of the logic address as address meta-information for each set of index information for a document. This is shown in more detail in FIG. 4 .
FIG. 4 shows a particular embodiment of the present invention. In this case, at the time of the index import, i.e., when index data is loaded into the central archive system, a logic address in the external archive system in which the particular document is physically stored is at the same time loaded into the index for the document which is stored on the central archive system. Also, these logic addresses are managed as 1-N relations within the central archive system, i.e., one logic address is assigned to a plurality of real addresses, with one element being marked out as CURRENT. When a list of search results is supplied, the logic address is supplied along with it as part of the index information on a document. What this implies is that at the time when they are run, company-specific applications must make a conversion from the logic address to the real address. This is done on the basis of an address catalogue. An address catalogue provides at all times an overview of the external archiving systems logged on within a central archive system, of these system' defined backup systems and of the primary server which is current at the time. Changes cause a new catalogue to be produced and stored.
Internally, the catalogue is stored in record format for supply with an optimised standard of performance (few central accesses).
FIG. 4 is a schematic view of the process of supplying the address catalogue. When a document request is made, the application takes the logic address, has the front-end server convert it into a real address, and makes a direct connection to the external archiving system. Rather than accessing the front-end server, the application could undertake the conversion itself if the address catalogue were stored internally.
When a new archive system is introduced or the address of an archive system is changed, a new address catalogue is produced. The address catalogue is stored in the central archive system and supplied to the external central archive interface and stored there. In the event of changes to the address catalogue, a new address catalogue is generated, stored in the central archive system and supplied to the external archive system interfaces. The address catalogue can also be loaded directly into the user system on which the application is stored.
The address catalogue is supplied on a time-stamp basis, i.e., the time stamp is compared with the date of generation. If the date of generation is more recent, the catalogue is supplied. The decentralized storage of the address catalogue prevents multiple accesses to the central archive system. When there are changes, the address catalogue is replaced in toto. This prevents inconsistencies and does away with the need for a log to be kept of the individual changes.
In a further embodiment of the present invention, the embodiments shown in FIGS. 3 and 4 can be combined.
When this is the case, the real address plus x backup addresses (when defined) and the address catalogue are supplied by the central archive system to the external central archive interface. When a document is selected from a list of search results, it is the real server address which is used to make the connection to the external archiving system. If the connection cannot be made, either the correct real address or the address of a backup server is asked for from the address catalogue via the front-end server. The document which is wanted is now requested without a diversion through the central archive.
It is to be understood that the embodiments and variations shown and described herein are merely illustrative of the principles of this invention and that various modifications may be implemented by those skilled in the art without departing from the scope and spirit of the invention. | The present invention relates to flexible facilities for supplying documents where the index to the documents is stored in a central archive but the documents themselves are stored in an external archiving system. The solution according to the invention is based on management of the addresses in the external archiving systems which is undertaken at the central archive. The approach adopted supports the specifying of any desired number of backup servers and, by allowing the configurable supply either of the address relation itself and/or of server address information attached to the list of search results, it provides a facility which supports the full range of document supply capabilities available when a central archive system is being used. | 8 |
RELATED APPLICATIONS
[0001] This patent application is a continuation of U.S. Nonprovisional Patent Application Ser. No. 11/103,956, filed on Apr. 12, 2005, which further claimed priority to U.S. Provisional Patent Application Ser. No. 60/561,669 filed on Apr. 13, 2004, both of which are incorporated by reference in their entirety.
TECHNICAL FIELD OF THE INVENTION
[0002] The present invention relates to a chemical composition and the use of the chemical composition to increase oil production and reserves.
BACKGROUND OF THE INVENTION
[0003] When oil is present in subterranean rock formations such as sandstone, carbonate, or shale, the oil can generally be exploited by drilling a borehole into the oil-bearing formation and allowing existing pressure gradients to force the oil up the borehole. This process is known as primary recovery. If and when the pressure gradients are insufficient to produce oil at the desired rate, it is customary to carry out an improved recovery method to recover additional oil. This process is known as secondary recovery. Primary oil recovery followed by secondary oil recovery, such as injection of water or gas to force out additional oil, are able to remove generally around 30 percent of the total oil content of an oil reservoir in many fields.
[0004] In waterflooding, pressurized water is injected into the oil-bearing formation after primary recovery and produced from neighboring hydrocarbon production wells. First hydrocarbon, and subsequently hydrocarbon and water are recovered from the production well.
[0005] Even after secondary recovery such as waterflooding, large amounts of the original oil remain in place. The fraction of unrecoverable hydrocarbon is typically highest for heavy oils, tar, and complex formations. In large oil fields, more than a billion barrels of oil can be left after conventional waterflooding. In addition to waterflooding, carbon-dioxide-miscible flood projects are also used. Tertiary recovery then becomes the focus. It is estimated that current tertiary oil recovery techniques have the ability to remove an additional 5 to 20 percent of the oil remaining in the reservoir. Given the current world dependence on fossil hydrocarbons, the development of effective tertiary oil recovery strategies for higher oil recovery promises to have a significant economic impact. Current methods of tertiary recover are effective, but expensive. Current tertiary methods still leave significant amounts of original oil in place in the field.
[0006] Much of the remaining oil in place after primary and secondary recovery is in micro-traps due to capillary forces or adsorbed onto mineral surfaces through irreducible oil saturation as well as bypassed oil within the rock formation. Encouraging movement of normally immobile residual oil or other hydrocarbon is commonly termed tertiary recovery. It is known to use microorganisms such as bacteria to dislodge the oil in micro-traps or adsorbed onto mineral surfaces to recover additional oil during the waterflooding phase. This typically involves the introduction of a microorganism from outside. These microbes create methane, which is then recovered.
[0007] It is also known that polymers and gelled or crosslinked water-soluble polymers are useful in enhanced oil recovery and other oil field operations. They have been used to alter the permeability of underground formations in order to enhance the effectiveness of water flooding operations. Generally, polymers or polymers along with a gelling agent such as an appropriate crosslinking agent in a liquid are injected into the formation. Both microbe-based and polymer-based enhanced recovery are expensive processes.
[0008] The diagenetic fabrics and porosity types found in various hydrocarbon-bearing rocks can indicate reservoir flow capacity, storage capacity and potential for water or CO2 flooding. The goal is to force oil out of high-storage-capacity but low-recovery units into a higher recovery unit. This allows an increase of recovery of oil over predicted primary depletion recovery such that a higher percentage of the original oil in place is recovered.
[0009] Traditional tertiary recovery operations include injection of the CO2 or water into the well. There is a need for an improved composition for enhanced oil recovery. It would be advantageous to use commercially available traditional injection facilities to reduce capital expenditures.
[0010] To fully capitalize on their national resources, oil-producing countries must enhance domestic petroleum production through the use of advanced-oil recovery technology. Operating companies, typically conservative in stating recoverable reserves, have a need to increase recoverable reserves from proven reserves as opposed to development of unproven reserves. There is a need for cost effective oil recovery techniques to maximize removal of original oil in place per field. There is a need for a cost effective oil recovery technique to reduce development costs by more closely delineating minimum field size and other parameters necessary to successfully recover oil. There is a need for tertiary recovery that can utilize simple or current application procedures.
[0011] U.S. Pat. No. 6,225,263 teaches a method of increasing the recovery of oil and/or gas from an underground formation by injecting into the formation an aqueous solution of a mono alkyl ether of polyethylene glycol.
[0012] U.S. Pat. No. 3,902,557 describes a method of treating the formation surrounding a well by injection of a solvent including a C 4 to C 10 alkyl ether of a polyglycol ether containing a C 4 to C 10 alkyl ether of a polyglycol ether containing 10-22 carbon atoms per molecule. C 4 to C 8 monoalkyl ethers of tri and tetra ethylene glycols are preferred in particular the hexyl ether while the butyl ether is also mentioned. The solvent may be diluted with an organic liquid such as alcohol, e.g. isopropanol.
[0013] FR Patent No 2735524 is directed toward a method of secondary and tertiary recovery through the use of alcohol in an amount of 1 to 5% by weight to solvate asphaltenes.
[0014] A need exists for a cost effective composition and method of use of the composition to improve enhanced oil recovery. There is a need to capitalize on the original oil in place that is unrecovered by primary and/or secondary recovery method.
SUMMARY OF THE INVENTION
[0015] In order to meet one or more of these needs, the present invention advantageously provides a composition and method for tertiary oil recovery. The invention includes a cost effective custom-designed blend of organic chemicals to stimulate oil production. Whether through surfactant or solvent action, this composition mobilizes residual oil trapped in the reservoir.
[0016] The invention includes a chemical composition for use in drilling operations for oil recovery and the method of using the chemical composition. The chemical composition includes an ammonia compound, an alcohol, and aqueous carrier solution. The aqueous carrier solution is of sufficient volume such that it is operable to fully dissolve the ammonia compound and alcohol in the aqueous carrier solution. While heating is not required, slight elevation of the temperature has shown positive effects. The chemical composition exhibits the ammonia compound and the alcohol substantially distributed throughout the carrier fluid.
[0017] In a preferred embodiment, the alcohol useful in the chemical composition of the invention contains from about one to about six carbon atoms. The alcohol is preferably non-aromatic. More particularly, alcohols containing one to four carbons are particularly useful, i.e. methyl, ethyl, propyl, and/or buytl alcohol. Of the propyl alcohols, isopropyl alcohol is particularly preferred. Alcohol is preferred in an amount of approximately 4 to 16 percent by volume of the chemical composition.
[0018] In the chemical composition of the invention, a preferred carrier solution is water. This solution can also be salt water such as produced waters. Aqueous carrier solutions are preferred. In a preferred embodiment, there is only one carrier solution and it is just water. The carrier solution in an amount of approximately 76 to 94 percent by volume of the chemical composition is preferred.
[0019] The ammonia compound of the chemical composition is preferably ammonia or ammonium hydroxide. The ammonia compound present in an amount of approximately 2 to 8 percent by volume of the chemical composition.
[0020] The preferred amounts of the ammonia compound and the alcohol define a range of ratios that are preferred. The preferred ratio of alcohol to ammonia compound is between approximately 1:1 alcohol to ammonia and approximately 3:1 alcohol to ammonia, the ratio being on a volume basis. The ratio of approximately 2:1 alcohol to ammonia is particularly preferred.
[0021] This invention also includes a process for recovering hydrocarbons from a hydrocarbon formation containing hydrocarbon reserves. The process of the invention includes introducing the chemical composition into the hydrocarbon formation in an amount effective to substantially increase the recovery of hydrocarbons from the formation. The subsequent recovery of hydrocarbons from the hydrocarbon formation can be through the same well or through other wells in the field.
[0022] The current invention can be used as secondary and/or tertiary recovery. The composition of the invention is believed to improve the permeability of the formation adjacent to the well bore.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] So that the manner in which the features, advantages and objects of the invention, as well as others that will become apparent, may be understood in more detail, more particular description of the invention briefly summarized above may be had by reference to the embodiment thereof that are illustrated in the appended drawings, which form a part of this specification. It is to be noted, however, that the drawings illustrate only a preferred embodiment of the invention and are therefore not to be considered limiting of the invention's scope as it may admit to other equally effective embodiments.
[0024] FIG. 1 is a simplified flow diagram of injection of the chemical compound of the invention into a reservoir; and
[0025] FIG. 2 is a simplified flow diagram of equipment useful for one embodiment of the invention that includes injecting produced water with the chemical composition of the invention into a well
DETAILED DESCRIPTION
[0026] For simplification of the drawings, figure numbers are the same in FIG. 1 and FIG. 2 for various streams and equipment when the functions are the same, with respect to the streams or equipment, in each of the figures. Like numbers refer to like elements throughout, and prime, double prime, and triple prime notation, where used, generally indicate similar elements in alternative embodiments.
[0027] Alcohols can generally be defined as R—OH where R is a combination of carbon and hydrogen atoms, water being excluded from such definition. The preferred alcohol of the. invention is straight chained, as opposed to an aromatic, with a continuous chain of carbon atoms from 1 to 8 carbons long. Saturated alcohols are generally preferred as they tend to be more stable than unsaturated alcohols. Methyl alcohol, ethyl alcohol, i-propyl alcohol, n-propyl alcohol and butyl alcohol are preferred. Propyl alcohol is particularly preferred. Of the propyl alcohols, isopropyl alcohol is particularly preferred. Mixtures of methyl, ethyl, propyl and/or butyl alcohols to create the alcohol of the invention are also encompassed in this invention. A mixture of ethyl and propyl alcohol is preferred. As the chemistry of the alcohol molecule is dominated by the functional OH group, it is understood by those skilled in the art that other alcohols can be effective alone or in combination. However, the use of only one alcohol having a continuous chain of 1 to 8 carbons or only one alcohol, that alcohol being the mixture of the one to eight carbon alcohols without other alcohols, is effective and preferred.
[0028] Notably, alcohols can also be created in situ, for example, through the reaction of salts with appropriate reagents in the presence of water. Creation of the alcohol in situ is also encompassed in this invention.
[0029] Additionally, surfactants can be added to the chemical composition in order to decrease the water-oil interfacial tension and to improve the efficiency, but the invention provides efficient and cost-effective results through the use of a mixture of only the ammonia compound, the alcohol and the carrier solution.
[0030] Ammonia is added to the chemical composition. Ammonia can be provided in many forms, the preferred forms being anhydrous ammonia and ammonium hydroxide. Ammonia can be produced by reaction or dissociation. Ammonium ions such as dissolved ammonium salts are also encompassed within the invention. Ammonia is quite soluble in water, dissolving to the extent of about 700 volumes in 1 volume of solvent. The dissolving process is accompanied by the reaction NH3+H2O thereby producing NH4++OH—. This is referred to as ammonium hydroxide. Therefore, ammonium hydroxide, which is often produced commercially with significant amounts of ammonia in water, is included in the term ammonia in this invention. Also encompassed are other precursors that form the ammonium ion in situ.
[0031] Isopropyl alcohol, also known as isopropanol, has a formula of C 3 H 8 O and is unsaturated. This is a particularly preferred alcohol of the invention. It is noted that isopropyl alcohol has a boiling point of 82.4 degrees C. and specific gravity: 0.78 at 20 degrees C. The air odor threshold concentration of isopropyl alcohol to be as 22 parts per million (ppm) parts of air. Contact between isopropyl alcohol and air occasionally results in the formation of peroxides, another possible element of the composition, whether added or created in situ. Therefore, an alternate embodiment of the invention includes the addition of peroxide to the ammonia compound and alcohol. Isopropyl alcohol is believed to change the wettability of the strata, particularly at the interface of the fracture and rock matrix. Viscocification is achieved by altering the properties of the reservoir fluid.
EXAMPLE 1
[0032] Anhydrous ammonia is used in this example, Baume 26.
[0000]
isopropyl
anhydrous
alcohol
ammonia
water
volume %
8
4
88
[0033] The resulting composition was diluted five times such that there was 1 part composition of the invention and 4 parts diluent. Water was used as the diluent. Salt water from produced waters can also be used. This was tested on well and substantially increased recovery was observed.
EXAMPLE 2
[0034] Test is identified as test #1300. Following is a chart comparing the chemical composition of the invention to connate water:
[0000]
Surface Viscosity
Density
#1300
mPa · s
g/cm3
pH
Chemical
0.79
0.958
11.635
Connate
0.83
0.985
9.439
water #1
Connate
0.78
0.982
9.362
water #2
[0035] This example was run at concentration of 0% (to mimic connate water), 0.2%, 0.5%, 1.0%, 2.0%, 4.0%, 6.0%, 8.0%, 10%, 15%, 20% and 100%.
[0036] The results of these tests indicate that the solubility of the chemical composition is good in different concentration.
EXAMPLE 3
[0037] Test is identified as test #700. Following is a chart comparing the chemical composition of the invention to connate water:
[0000]
Surface Viscosity
Density
#700
mPa · s
g/cm3
pH
Chemical
0.83
0.964
11.791
Connate
0.83
0.985
9.439
water #1
Connate
0.78
0.982
9.362
water #2
[0038] The chemical can be recovered and recycled to further decrease costs. The chemical composition does not appear to react with oil nor is a significant amount trapped in the formation. Therefore, the chemical composition can be separated from oil/fluid and recycled.
[0039] While the invention has been shown or described in only some of its forms, it should be apparent to those skilled in the art that it is not so limited, but is susceptible to various changes without departing from the scope of the invention.
[0040] For example, while this invention has been described as useful for tertiary recovery, it can be used to stimulate production at any point during the life of the well, including in conjunction with secondary flooding. While traditional injection equipment has been described, the invention includes any method of bringing the chemical composition into contact with the oil producing strata. Various means of forming the chemical composition, including creation in situ, are encompassed in this invention. Uses for the chemical composition related to the properties recognized in the composition are also encompassed within this invention. The method of the invention may be applied to well stimulation treatments such as water blocking, sand consolidation, sandstone acidizing and methods of increasing the recovery of oil such as tertiary oil recovery. The chemical composition can be injected into a producing well or at a distance from a producing well to drive the hydrocarbons to the well. Gelled or viscosified means of delivering this chemical composition are also encompassed in the invention. | The present invention includes a cost effective custom-designed blend of organic chemicals to stimulate oil production. The invention includes a chemical composition for use in drilling operations for oil recovery and the method of using the chemical composition. The chemical composition includes an ammonia compound, an alcohol, and aqueous carrier solution. The aqueous carrier solution is of sufficient volume such that it is operable to fully dissolve the ammonia compound and alcohol in the aqueous carrier solution. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is claiming the benefit of priority to U.S. provisional application Ser. No. 60/365,147 filed on Mar. 14, 2002 of which is incorporated herein by reference in its entirety.
FIELD OF INVENTION
This device is a vehicle for scraping earth from regions containing land mines or munitions. The scraped earth is separated into munitions and earth, the earth is allowed to exit the vehicle's scraper bowl. The munitions and land mines are retained in the scraper bowl. The device is additionally armored in those regions where explosion of the cargo carrying, e.g., land mines, is found. Additionally, the device may be robotically operated.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partial cutaway drawing of a typical elevating scraper.
FIGS. 2 , 3 , 4 , 5 , and 6 A are cutaway drawings of elevator scraper bowls showing suitable placement of separators within the scraper bowls and various conveyors for moving scraped earth to the separators.
FIG. 6B is a view of a grizzley-type screen used in the variation shown in FIG. 6A .
FIGS. 7 , 8 , 9 , and 10 show various separators suitable for use in the bowls shown in FIGS. 2–6A .
FIGS. 11A and 11B show a separator suitable for use in the invention having adjustable, spacing between separator bars.
DESCRIPTION OF THE INVENTION
FIG. 1 shows a partial cutaway drawing of a known elevating scraper vehicle ( 100 ), such as are manufactured by the Caterpillar Co. Typical commercial variations of the vehicle include a tractor assembly ( 102 ) having a pair of drive wheels ( 104 ) and a scraper bowl assembly ( 106 ). The scraper bowl assembly ( 106 ) typically includes a pair of wheels ( 108 ) that are pulled along. The tractor assembly ( 102 ) and the scraper bowl assembly ( 106 ) are articulable with respect to each other around an articulation joint ( 110 ). The articulation joint allows the vehicle ( 100 ) to be driven and steered using only the front wheels ( 108 ) without turning the front wheels ( 108 ), if the designer so elects. The front wheels ( 108 ) may be turned at differing rates to turn the vehicles.
The elevating scraper vehicle ( 100 ) operates in earthmoving operations in the following way: as the vehicle ( 100 ) moves forward, a scraper blade ( 112 ) passes along the surface of the ground ( 114 ). The scraper blade ( 112 ) may be adjusted vertically to take more-or-less of a cut from the earth surface ( 114 ). The then-scraped earth passes into the domain of a conveyor ( 116 ) often having buckets, tabs, or paddles ( 118 ) to assist in pulling earth to a level where it is dumped, in slightly “sized” chunks, into scraper bowl ( 120 ) along the arrow-marked path ( 122 ). A deflector ( 124 ) may be used in cooperation with the conveyor ( 116 ) to center the scraped earth in the bowl ( 120 ) and provide for accommodation of a larger load.
Once the scraper bowl ( 120 ) has been filled to appropriate level, the commercial variation is then able to remove a covering or door from the bottom of the scraper bowl ( 120 ) and allow the scraped earth to fall from the bottom of the bowl onto selected a site. The door is then closed so that the vehicle may then go back to additional earth scraping operations.
My invention is one in which the vehicle is adapted so that it scrapes earth, possibly that has been previously loosened, to pick up the larger sizes of ordnance, munitions, or land mines. In concept, my invention removes a layer of earth, passes it through a separator via a conveyor, where the conveyor is sized in such a way that it retains the sought-after ordnance or land mines on the separator and allows the earth to pass through the separator and out of the bucket. It is best that the separator be shaken as the earth and ordnance or land mines are passed over it, since shaking separates the earth from the ammunition somewhat ,pre efficiently. Also desirable in this variation is the addition of shielding or armor over the various hydraulic and electrical components in the vicinity of the scraper bowl. Finally, because of the inherently dangerous task of performed by this device, the vehicle is preferably operated with robotic controls.
FIGS. 2 and 3 show alternative elevators found in elevating scrapers of various vintages in addition to showing placement of the filter or separator.
FIG. 2 shows a conveyor ( 300 ) that moves to assist scraped dirt into the scraper bowl ( 120 ). In this variation, the separator ( 302 ) is placed above the opening ( 304 ) in the bottom of the scraper bowl ( 120 ). Similar placement is shown in FIG. 3 . Again, the separator ( 302 ) is placed above the opening in the floor of the scraper bowl ( 120 ). In this variation, the elevator or earth conveyor ( 306 ) is helical screw.
FIG. 4 shows still another variation in which the separator ( 320 ) is placed adjacent to the conveyor belt ( 300 ). As was noted above, desirably the separator ( 320 ) is shaken during usage. In this variation, an opening ( 322 ) additional to that found in FIGS. 2 and 3 is maintained in the bottom of the scraper bowl ( 120 ). This variation allows for multiple sites for separation of the ordnance and multiple opening through which the earth may exit the lower side of the separator. In this variation, an additional separator ( 302 ) may optionally be maintained over another opening ( 304 ) in the separator bowl ( 120 ). This variation is quite efficient in separating earth from the desired munitions or land mines. There may be a wall ( 324 ) that maintains the integrity of the open topped volume ( 326 ) in scraper bowl ( 120 ). Wall ( 324 ) also serves to deflect earth passing through separator ( 320 ) down through opening ( 322 ).
FIG. 5 shows a variation in which the conveyor ( 300 ) moves as shown to assist scraped material into the scraper bowl ( 120 ). The separator in this variation is a shaken screen tilted towards a front (preferably armored) compartment ( 321 ) positioned in scraper bowl ( 120 ). This armored compartment ( 321 ) collects ordnance separated by the tilted separator (e.g., a screen) ( 302 ). The ordnance items may be removed from the compartment ( 321 ) by opening the lower door ( 323 ) located in the bottom of that front compartment.( 321 ). Earth picked up by the scraper and conveyor ( 300 ) passes through the screen (( 302 ) often a shaken screen) and drops through opening ( 304 ) to the ground.
FIG. 6A shows another variation in which multiple screens/separators are used to separate ordnance from scraped material or soil. This variation uses a coarse screening stage having a “grizzley” ( 330 ) that separates large stumps, rocks, etc. from the material scraped and dumps them through the open bottom ( 331 ) of the scraper bowl ( 120 ). FIG. 6B shows a top view of a grizzley ( 330 ) with its separator bars ( 336 ) and the coarse screens ( 338 ). The path taken by rejected by rejected stumps is shown at 332 ). Material passing through the grizzley ( 330 ) is then subjected to one or more screens ( 338 , 340 ) that may be of the same screen size or of sequentially finer in screen size. The material that does pass through follows path 342 through the open bottom ( 331 ) of the scraper bowl ( 120 ). Any separated ordnance falls from the screens ( 338 , 340 ) to collector ( 344 ). As is the case with all of the screens, they may be shaken or not, as desired.
FIGS. 7 , 8 , 9 , 10 , 11 A, and 11 B all show variations of separators that are configured to accept scraped earth from the earth lifter or conveyor and allow the so-separated earth to fall through.
FIG. 7 shows first a variation of ( 400 ) having a frame ( 402 ) and a number of rods ( 404 ) which together all form a device that will separate desired ordnance or land mines from the scraped earth. The spacing between adjacent rods ( 404 ) is selected to allow such separation.
FIG. 8 shows another variation of separator ( 406 ) having a somewhat solid separator face ( 408 ) having a large number of open holes ( 410 ). Again, the open holes ( 410 ) are sized in such a way that the sought-after materials stay within the frame ( 412 ).
FIG. 9 shows still another variation of the separator having a frame ( 414 ) separated by wires or rods ( 416 ) passing in two directions within the frame ( 414 ). The variation shown in FIG. 7 had rods or wires running only in a single direction.
FIG. 10 shows a variation of the device ( 418 ) that is frameless but having stiffener rods ( 420 ) supporting the separator rods ( 422 ) from each other in a spaced condition. The variation shown in ( 418 ) shown in FIG. 10 is particularly useful for the FIG. 4 variation of the device. This variation having vertical rods ( 422 ) pass along the path of the conveyor belt is quite sturdy and makes a fine first cut of earth as it passes by in the same direction as the lay of rods ( 422 ).
FIGS. 11A and 11B show one manner in which the spacing between adjacent separating rods or members may be adjusted. FIG. 11A shows an end view of three separator bars ( 430 ) each having a rotational axis ( 432 ) about which the bars may be rotated. The spacing between adjacent bars ( 430 ) in FIG. 11A is at a maximum.
FIG. 11B shows the rotation of separator bars ( 430 ) in such a way that the practical spacing between the bars is made smaller. The trade-off for adjustability is typically complexity. Nevertheless, should an adjustable width be desired, the variation showed in FIGS. 11A and 11B is quite useful.
This vehicle is used in the following fashion: the vehicle having an elevating scraper is pulled over earth containing material selected from ordnance, ammunition, and land mines. The earth contain those materials is scraped into the elevating scraper. This is passed over one or more separators, the separators being sized to remove the offending materials from the earth, and the earth is allowed to pass through the separator openings back to the ground. Additionally, the earth may be broken up in some fashion prior to its entry into the scraper. The separators may be shaken during the step of recovering materials from the scraped earth.
Although preferred embodiments of the invention have been described herein, it will be recognized that a variety of changes and modifications can be made without separating from the spirit of the invention as found in the claims that follow. | This device is a vehicle for scraping earth from regions containing land mines or munitions. The scraped earth is separated into munitions and earth, the earth is allowed to exit the vehicle's scraper bowl. The munitions and land mines are retained in the scraper bowl. The device is additionally armored in those regions where explosion of the cargo carrying, e.g., land mines, is found. Additionally, the device may be robotically operated. | 5 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority of German application No. 10 2006 008 723.2 filed Feb. 24, 2006, which is incorporated by reference herein in its entirety.
FIELD OF THE INVENTION
[0002] The invention relates to a method for sterilizing medical objects in a sterilization facility. The invention also relates to a corresponding sterilization device for sterilizing medical objects and a medical object, with which a corresponding sterilization method can be carried out. The medical objects as referred to in this invention can be any medical accessory, medical tools or instruments, such as catheters, endoscopes, needles, drill bits, etc. for example.
BACKGROUND OF THE INVENTION
[0003] The purpose of sterilization is to render an object into a microorganism-free and therefore non-infectious state by killing off possible pathogenic microorganisms. Sterilization is of major importance here, to prevent dangerous and in some circumstances life-threatening infectious diseases in particular in medical practices and hospitals—particularly after intervention during an operation. There are therefore relatively strict rules governing the manner in which certain medical objects should be sterilized. One generally known sterilization method is that of immersing the medical object in question in a sterilizing solution containing corresponding chemicals or washing the object with such a solution. There is also a plurality of further sterilization methods known to the person skilled in the art, such as steam sterilization, hot-air sterilization, gas sterilization, radiation sterilization and plasma sterilization for example. Some of these sterilization methods can have a very major impact on the medical object involved. For example sterilization processes using strong chemicals, UV radiation, radioactive radiation or by means of heat or hot steam or gas exposure frequently result in a greater level of material fatigue, thereby shortening the life of the medical objects. It is therefore stipulated for some medical objects that they can no longer continue to be used after they have undergone a certain number of sterilization cycles, as there is a greater risk that the object in question will be destroyed or fail during subsequent use. This is particularly important in the case of medical objects such as catheters or endoscopes, which are inserted into the human body. In the case of such instruments it is necessary for example to ensure in a reliable manner that part of the object, for example a tip, does not break off, thereby resulting in the risk of injury or parts of objects unintentionally remaining in the body of the patient in an uncontrolled manner.
[0004] Until now the staff carrying out the sterilization logged which object had already been sterilized and how often either manually or in a computer-aided manner. To this end the objects are generally identified uniquely by means of labels, engravings, etc., so that a corresponding list can be kept of when and where the respective medical object was sterilized using which sterilization process.
[0005] These methods are disadvantageous in that the careful management of corresponding log lists is very time-consuming and there is a risk of incorrect entries, for example if two identical medical objects with similar markings are confused and the entries are therefore not made correctly.
SUMMARY OF THE INVENTION
[0006] One object of the present invention is to provide a method for sterilizing medical objects and a suitable sterilization facility and a corresponding medical object, with which it can be ensured in a less time-consuming yet more reliable manner that a medical object is not sterilized again and further used after exceeding the permitted number of sterilization cycles.
[0007] This object is achieved by a method, a sterilization device, and a medical object according to the claims.
[0008] With an inventive method for sterilizing medical objects in a sterilization device, a read facility of the sterilization device first reads a machine-readable information code by means of electromagnetic waves from an identification element associated with the medical object. Such an identification element is preferably a transponder, in other words a module with an electronic circuit, which is prompted by means of the electromagnetic waves to transmit the information stored in the circuit. A typical example of such a transponder is what is known as an RFID tag (RFID=Radio Frequency Identification). The transponder does not require a power supply for this. The power is simply obtained from the electromagnetic waves of the read facility.
[0009] The information code can hereby allow precise object identification and/or contain information about the type of medical object, for example model, year of manufacture, etc., as well as further details, in particular about the specific sterilization process stipulated for the correct sterilization of the medical object in question. According to the invention this information code is used to determine the number of sterilization cycles, which the medical object in question has undergone. The number of sterilization cycles already undergone is then compared with the maximum number of permitted sterilization cycles that the medical object in question is allowed to undergo. A control facility of the sterilization device then automatically triggers a warning signal and/or restricts the function of the sterilization device, deactivating the sterilization device for example, if the number of sterilization cycles undergone reaches or exceeds the maximum number of permitted sterilization cycles.
[0010] It is thus possible in a fully automatic and reliable manner to prevent a medical object, which is not permitted a further sterilization cycle, incorrectly being resterilized and used once again.
[0011] A suitable sterilization device for sterilizing medical objects requires a read facility on the one hand, to read a machine-readable information code by means of electromagnetic waves from an identification element associated with a medical object. The sterilization device also requires an evaluation unit, to determine the number of sterilization cycles that the medical object in question has undergone based on the information code, and a comparator unit, to compare the number of sterilization cycles already undergone with the maximum number of permitted sterilization cycles the medical object in question is allowed to undergo. The sterilization device must also be fitted with a corresponding control facility, which is configured such that it automatically triggers a warning signal and/or restricts the function of the sterilization facility, if the number or sterilization cycles undergone reaches or exceeds the maximum permitted number of sterilization cycles. The evaluation unit and comparator unit can thereby also be part of the control facility, as can the read facility.
[0012] The dependent claims each contain particularly advantageous embodiments and developments of the invention, it being possible also to develop the dependent claims in particular according to the features of the dependent method claims and vice versa.
[0013] There are essentially a number of different possible ways to determine the number of sterilization cycles already undergone and the number of times a certain medical object can be sterilized as a maximum on the basis of the information code.
[0014] Thus for example, with one variant of the invention, additional information about the medical object to be sterilized can be determined on the basis of the information code from an external data source, to which the sterilization device is linked, for example a central database of a clinic, a practice, etc., or from the Internet. Information about the medical object can also be sent. It is thus possible for example to store the number of sterilization cycles carried out in a central database and retrieve it from there again. Similarly it is possible to store all the information about the medical object in question in such a database, in particular the maximum number of sterilization cycles permitted for said medical object. Data about the sterilization processes stipulated for the respective medical object during sterilization can also be stored here.
[0015] To this end the sterilization device requires a corresponding data interface, for example a link to an intranet bus or to the Internet, in order to be able to retrieve the corresponding information from the required external data source or to send the information.
[0016] In one particularly preferred variant however the information code itself contains a first characteristic value representing the number of sterilization cycles the medical object has undergone to date. This characteristic value can for example be a numeral directly, which states the number of sterilization cycles undergone. It can however also for example be a number of flags set within a binary code, etc. When the medical object in question undergoes further sterilization, the characteristic value is automatically overwritten or adjusted by way of a transmit unit of the sterilization device. The characteristic value or number of sterilization cycles can for example be adjusted in instances where the number of sterilization cycles is encrypted in the form of flags set within the information code. A new additional flag is then set correspondingly. Alternatively the information code can be wholly or partially overwritten, to change at least the part of the information code containing the said characteristic value.
[0017] With this variant the medical object therefore has an identification element, which contains a machine-readable information code, containing information about the number of sterilization cycles the medical object has already undergone. It is therefore no longer necessary to clarify in an external database—for example on the basis of an identifier—which or how many sterilization cycles the medical object in question has already undergone. This makes the overall process more reliable, as the number of sterilization cycles undergone is associated directly with the medical object.
[0018] To achieve maximum reliability, it is also possible to use a combined method. In other words the precise number of sterilization cycles already undergone is stored in each instance directly within the information code in the identification element and can be read from there and updated at any time. This value is then compared with a corresponding value in a central database and a warning signal is output in the event of an incorrect entry.
[0019] In order to change the number of sterilization cycles carried out in the information code, the sterilization device requires a corresponding transmit unit, to link a specific information code to a medical object and/or to change an information code linked to a medical object. The identification element must also be configured correspondingly such that the information code can subsequently be changed by means of electromagnetic waves by way of a transmit unit.
[0020] A combined read/transmit unit, particularly preferably an RFID read and/or write facility, is used as a preferred alternative to separate read facilities and transmit units for this purpose. The identification element therefore preferably comprises an RFID tag. To produce such an RFID tag only 300 μm to 400 μm thin labels for example are fitted with an extremely flat microchip for the data to be stored—in this instance the information code—and an associated miniature antenna made of copper or aluminum film, which is laminated onto a thin PET carrier film. When a spatially remote read facility transmits an electromagnetic high-frequency field, for example at a frequency of 13.56 MHz, which the RFID tag receives, the stored data is sent back to the read facility on the same path. Similarly the RFID tag can also be written with data. The transmission of information between the RFID tag and the read facility functions without visual contact with a range of one to several meters.
[0021] It is quite particularly preferable for the information code also to contain a maximum value, representing the maximum number of permitted sterilization cycles the medical object is allowed to undergo. This maximum value can also be encrypted directly or indirectly in the information code, for example again by means of a simple numeral or a number of flags set in a binary code, etc. This direct storage of the maximum value has the advantage that the sterilization facility or its control facility can immediately verify very simply, by comparing the first characteristic value with the maximum value, whether the maximum value has been reached or exceeded, without requiring access to a database—whether internal or external. As a result the sterilization process can also be carried out according to the invention, if the sterilization device in question has no link to an external central database either temporally or permanently.
[0022] The advantage of this method is that the medical object can be sterilized in different sterilization devices—in larger clinics even in different departments—without said sterilization devices having to be networked. Each of the sterilization devices can determine for itself, based on the data contained in the information code, whether a medical object has already undergone the maximum permitted number of sterilization cycles or whether it can be used again.
[0023] If however there is corresponding networking of the sterilization device with an external data source, for example an intranet or the Internet, the sterilization facility can also send data to or receive data from an inventory control system or similar program. With a particularly preferred variant of the inventive method a corresponding new medical object is ordered automatically, when the medical object to be sterilized has undergone a specific replacement limit number of sterilization cycles. The replacement limit number of sterilization cycles is thereby of course a function of the maximum number of permitted sterilization cycles. Expediently the replacement limit number is also a function of the time period generally required to repurchase an ordered object of this type and the average frequency of the sterilization cycles, in other words the frequency with which the object is required. In this manner it can be ensured that a new medical object is automatically always available locally in a timely manner, when a specific medical object is no longer allowed to be used because it would exceed the maximum number of permitted sterilization cycles. A warning signal is preferably output to the operator additionally or alternatively, so that said operator is also informed that the object can now no longer be used.
[0024] It is obvious that—if an alarm is to be triggered by the control facility—the sterilization device requires a corresponding alarm facility.
[0025] The read facility is preferably disposed and configured on the sterilization device such that it automatically captures the information code of a medical object to be sterilized, when the medical object in question is moved into the sterilization area of the sterilization device. For example the read facility can be located in a door area of a sealable disinfection chamber.
[0026] It is particularly preferable for the sterilization device to have a sealable disinfection chamber and an activation facility, which automatically activates the read and/or transmit facility, when the disinfection chamber is opened.
[0027] The sterilization device advantageously also has a display facility, which is used to display information about a medical object to be sterilized determined on the basis of the information code. This information can be stored directly in the information code or can be retrieved from a database on the basis of the information code. The information displayed can for example include the number of sterilization cycles already undergone and the maximum number of permitted sterilization cycles in addition to details of the type of sterilization process stipulated for the medical object in question (i.e. the operating instructions for sterilizing the medical object in question). Alternatively or additionally the difference between these figures can also be displayed, in other words the number of sterilization cycles the object is still allowed to undergo, so that the operator is always provided with information about the remaining “life” of the medical object in question.
[0028] It is particularly advantageous for the control facility to be configured such that it activates the sterilization device automatically as a function of an information code of a medical object to be sterilized captured by the read facility, such that the medical object located in a sterilization area of the sterilization device undergoes a defined sterilization process. For example the control facility can automatically activate the available sterilization units, such as heater, fan, cooler, gas supply, fluid supply, suction, irradiation device etc. appropriately to carry out the required sterilization process in the sterilization area provided, such that the medical object to be sterilized is treated in a specific predetermined manner for a precisely predetermined time, for example being subjected to a specific temperature or a specific irradiation or gas exposure.
[0029] In a development of this variant it can also be verified on the basis of the machine-readable information code whether a number of medical objects, which have to undergo different sterilization processes, are located in one sterilization area of the sterilization facility. If such a conflict situation exists, a combined sterilization process (in other words a type of compromise sterilization process) is carried out, which is suitable—where possible—for sterilizing all the medical objects. To find such a combined sterilization process, the control facility can for example select a process sequence from a number of predetermined sterilization processes, with which it is ensured that on the one hand all the medical objects undergo the process steps required for each of them, whilst on the other hand ensuring that one of the medical objects does not require a sub-process, for example a specific irradiation, which could damage another medical object.
[0030] Alternatively or additionally a warning signal can also be triggered and/or the function of the sterilization facility is restricted, in other words for example the sterilization facility is taken out of operation completely. When a warning signal is output, the operator can for example remove one of the objects from the sterilization device, thereby resolving the conflict.
[0031] It is particularly preferable for the identification element and the read facility also to be used to determine the sub-area of a sterilization area of the sterilization facility in which a specific medical object is located. It is then possible to carry out a sterilization process specified for the medical object in question or a specific sub-process of said sterilization process, for example specific gas exposure or irradiation, in a preferably specific manner in this sub-area. This sub-process is then not carried out in other sub-areas of the sterilization area for example. Corresponding methods, to carry out a location with suitable identification elements, for example RFID tags, already exist. For example it is possible to measure the electromagnetic signals emitted by the identification element by means of a number of receive units within the sterilization facility and to use the signal propagation times and/or signal strengths to determine the position of the medical object in question.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] The invention is described in more detail below based on exemplary embodiments and with reference to the attached figures, in which:
[0033] FIG. 1 shows a schematic diagram of an exemplary embodiment of an inventive sterilization device in the closed state,
[0034] FIG. 2 shows a schematic diagram of the sterilization device according to FIG. 1 in the opened state with a medical object located therein,
[0035] FIG. 3 shows a detailed schematic diagram of the different functional components of the sterilization device according to FIGS. 1 and 2 ,
[0036] FIG. 4 shows a flow diagram for a possible process sequence during the sterilization of a medical object according to a variant of the present invention, and
[0037] FIG. 5 shows a schematic diagram of a sterilization area of a sterilization facility with a number of sub-areas.
DETAILED DESCRIPTION OF THE INVENTION
[0038] FIG. 1 shows a schematic diagram of a sterilization facility 1 in the form of a sterilization cabinet 1 with a display and control unit 2 disposed outside it, which an operator can use to operate the sterilization facility. A door 5 is located in the front area, which can be used to seal the sterilization chamber 4 within the sterilization cabinet 1 .
[0039] FIG. 2 shows the sterilization cabinet 1 in the opened state. Inside the sterilization chamber 4 are a number of shelf levels 6 or drawers, which divide the sterilization chamber 4 into a number of sub-areas 7 . Inside the sterilization device 1 , in this instance in the upper left corner, is an RFID read/write facility 8 . Next to this is an activation facility 23 , for example a pressure switch, which is used to activate the RFID read/write facility 8 when the door 5 is opened.
[0040] Inside the sterilization facility 1 a medical object to be sterilized O is shown schematically in this instance as a box, to which an RFID tag T is attached. An information code C is stored in this RFID tag, containing different information about the medical object O, such as its product name, serial number, manufacturer, date of manufacture, a recommended sterilization program and the number of sterilization cycles already undergone, as well as the maximum number of sterilization cycles the medical object O is allowed to undergo. This information code C is read, as soon as the medical object O is placed in the sterilization chamber 4 .
[0041] The information code C is then evaluated in a control facility 10 of the sterilization device 1 . A corresponding control facility 10 and further functional components of the sterilization device 1 are shown schematically in FIG. 3 .
[0042] The core element of the control facility 10 in this instance a central unit 11 , for example in the form of a microcontroller, on which different sterilization programs, monitoring programs, etc. can be operated. A further component in the control facility 10 is a time measurement facility 14 , for example a calendar and/or a clock, which is used to comply with specific process times or even—if this can be found on the basis of the information code—to monitor the maximum service life of the medical object.
[0043] The RFID read/write unit 8 is linked to the control facility 10 and is activated automatically by the activation unit 23 . The control facility 10 or central unit 11 can prompt the reading of the information code C from an RFID tag T or the writing of an RFID tag T by way of this RFID read/write unit. To this end the control facility 10 has an evaluation and interface unit 13 . A read information code C is analyzed or evaluated in this evaluation and interface unit 13 and the information contained therein, such as an identifier ID, the number of sterilization cycles already undergone N and the maximum permitted number N max of sterilization cycles is transmitted to the central unit 11 .
[0044] In the exemplary embodiment shown the central unit 11 contains a comparator unit 12 in the form of a program module, which first verifies, before a sterilization process is carried out, whether the number N of sterilization cycles already undergone has exceeded the maximum number N max of permitted sterilization cycles. The precise sequence of this method is described in more detail below with reference to FIG. 4 .
[0045] Additional information about the medical object to be sterilized O can be retrieved from a storage unit 17 for already registered objects. The control facility 10 can also communicate by way of an interface 15 with an external data network 22 or an external central database and obtain additional information 10 about the object O or output information in this manner. The sterilization units 3 , for example a heating facility, a fan facility, an irradiation facility etc., are activated by the control facility by way of a further interface 16 , so that corresponding sterilization processes are carried out within the sterilization chamber 4 or in sub-areas of said sterilization chamber 4 . The necessary sterilization units 3 are only shown schematically here in the form of a block.
[0046] In order to carry out precisely those sterilization processes, which are suitable for the respective medical objects, it is possible to store sterilization programs intended for specific object types in the storage unit 17 and these are then selected by the central unit 11 based on the information contained in the information code, such as object type, identification, serial number, etc.
[0047] The display unit 2 is also linked to the control facility 10 by way of a display interface 20 . This display unit 2 is generally controlled by way of a display processor 21 . Said display unit 2 is also linked by way of the display processor 21 to a control unit 19 , in this instance a touch screen control unit 19 , so that inputs can be activated when the operator presses certain display areas. Alternatively or additionally a standard keyboard can also be used and/or voice operation can be enabled with the aid of a voice recognition facility. An acoustic alarm unit 18 is also linked to the display interface 20 , so that the control facility can send an alarm signal AS to the acoustic alarm unit 18 by way of the display interface 20 , to trigger an alarm, for example if a medical object O placed in the sterilization chamber 4 of the sterilization facility 1 has already exceeded the maximum number N max of sterilization cycles. A corresponding display simultaneously appears on the display unit 2 .
[0048] A preferred process sequence for this purpose is shown in FIG. 4 . In a first step I the RFID read/write unit first automatically reads the information code C from the RFID tag T on the medical object O, as soon as the medical object O is placed in the sterilization facility 1 . In step II the number N of sterilization cycles already undergone, the maximum number N max of permitted sterilization cycles for the medical object O in question and the replacement limit number N or , the function of which is described further below, are then determined from the information code. In step III it is verified whether the number N of sterilization steps undergone is still below the number N max of permitted sterilization cycles. If not, no further sterilization can be carried out but in step IV an alarm is triggered and the process is aborted (step V).
[0049] Otherwise in step VI the desired sterilization is carried out, with the control facility 10 automatically selecting a suitable sterilization program from a database within the storage unit 17 on the basis of the information contained in the information code C. Alternatively information can also be contained directly within the information code C, about the sterilization process that has to be carried out with the medical object in question O, to ensure correct sterilization.
[0050] After sterilization has taken place, the number N of sterilization cycles undergone is increased by one counter in step VII. In step VIII the new value N is written into the RFID tag T on the medical object O. This is done by transmitting the new number N for example from the central unit 11 of the control facility to the evaluation and interface unit 13 and this latter prompting the RFID read/write unit 8 to transmit a corresponding signal to rewrite the RFID tag T on the medical object O (see FIG. 3 ).
[0051] Before the process is terminated in step XI, it is verified again in a process IX, whether the number N of sterilization cycles now undergone is below a replacement limit number N or . If not, in other words if the number N of sterilization cycles undergone has reached said replacement limit number N or , the medical object is automatically reordered in step X. This can be done for example by the central unit 11 automatically sending a corresponding order signal OS by way of the interface 15 to an external network 22 and from there for example to an inventory control system of the clinic or practice where the sterilization device is located. The replacement limit number N or should be selected such that with a normal sequence the new medical object is available locally before the time when the medical object has undergone the maximum number of sterilization cycles, in other words the replacement limit number N or should generally be correspondingly below the maximum number N max of permitted sterilization cycles. If a new medical object is available very quickly, the replacement limit number N or can however in principle also be equal to the maximum number N max of permitted sterilization cycles, in other words the new medical object is only ordered, when it has undergone the last permitted sterilization process.
[0052] FIG. 5 shows an exemplary embodiment of a particularly advantageous extension of this system. The sterilization area 4 here is divided into different sub-areas 7 a , 7 b , 7 c , 7 d at different levels. There are two RFID receiver/transmitters 8 a , 8 b , 8 c , 8 d , 8 a ′, 8 b ′, 8 c ′, 8 d ′ at each of these levels. All the RFID receiver/transmitters 8 a , 8 b , 8 c , 8 d , 8 a ′, 8 b ′, 8 c ′, 8 d ′ are linked to a central RFID control and location unit 9 and together with this form an RFID read and write facility, to read and/or write RFID tags. It is thereby possible to determine, with the aid of the RFID receiver/transmitters 8 a , 8 b , 8 c , 8 d , 8 a ′, 8 b ′, 8 c ′, 8 d ′ positioned at different locations, in which sub-area 7 a , 7 b , 7 c , 7 d a specific medical object O′ is located. This can be done for example by evaluating the signal strengths and/or propagation times of the RFID signals received by the RFID receiver/transmitters 8 a , 8 b , 8 c , 8 d , 8 a ′, 8 b ′, 8 c ′, 8 d′.
[0053] It can thus be determined that a first medical object O with a first RFID tag T is located at the lowest level 7 d , as the RFID receiver/transmitters 8 d , 8 d ′ and 8 c ′ receive the strongest signal in respect of said RFID Tag T and corresponding propagation times are present. At the same time it can be determined that a further medical object O′ is located at the second level 7 b , as the information code C′ from the RFID tag T′ of this medical object O′ is registered to the strongest degree by the RFID receiver/transmitters 8 b , 8 b ′, 8 c ′ and the propagation times correspond thereto.
[0054] As it can be determined precisely which medical objects are at which level 7 a , 7 b , 7 c , 7 d , different sterilization processes can then preferably also be carried out specifically at the different levels 7 a , 7 b , 7 c , 7 d . It is thus possible for example to subject the medical objects O, O′ to be sterilized to specific sub-processes, such as specific irradiation or gas exposure, at specific levels, ensuring that the medical objects at the other levels 7 a , 7 b , 7 c , 7 d are not affected. It is also possible to display by way of a display unit at which level which medical objects are located. This is particularly expedient in larger sterilization devices. Such geographical identification on the display unit means that in the event of an alarm (e.g. when N=N max ) the object triggering the alarm can be easily located and removed from the sterilization chamber.
[0055] To conclude, it should be pointed out once again that the method sequences and sterilization devices described in detail above are exemplary embodiments, which can be modified in many different ways by the person skilled in the art, without departing from the scope of the invention. It is therefore also possible for the control facility to be networked by way of a suitable interface with communication devices other than those mentioned above, for example further PCs, a TV, PDAs, Blackberry devices, mobile telephones, etc. It is thus possible for an operator, who is located at a different station, or even a service technician in the event of a breakdown, to be automatically called to load and unload the sterilization facility. | A method for sterilizing medical objects in a sterilization device is described. A read facility of the sterilization device first reads a machine-readable information code by means of electromagnetic waves from an identification element associated with the medical object. The number of sterilization cycles already undergone by the medical object in question is determined on the basis of the information code. The number of sterilization cycles already undergone is compared with the maximum number of permitted sterilization cycles the medical object in question is allowed to undergo and a warning signal is automatically triggered and/or the function of the sterilization device is restricted, if the number of sterilization cycles undergone reaches or exceeds the maximum number of permitted sterilization cycles. A corresponding sterilization device and a medical object are also described. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to electric lighting elements, light strings and lighted displays, and to methods of manufacturing the same.
2. Description of the Related Art
Smell sometimes can play as large a role as sight and sound typically do in creating and remembering an experience. For example, the smell of food cooking, the ocean, popcorn, or a pine tree often brings back memories of certain events or locations as fast or faster than the associated sights and sounds.
As a consequence, air fresheners and other scented articles, both natural and synthetic, have been developed to help create such an environment or bring back such a memory when the real smell is not available. Typically these devices are designed to be attractive or inconspicuous; for example, non-electric air fresheners may be designed to be adhered to the back or bottom of an article of furniture and electric air fresheners may be flat, small and light colored to blend in with the wall when plugged in.
Most air fresheners have a housing with a cavity in it that retains a scented fluid or gel. The fluid typically is held in a reservoir or absorbed in a porous body, while the gel may have enough structural integrity to be attached or coupled to the housing. When the scented fluid or gel evaporates, the fluid is refilled or the gel replaced to cause the air freshener to function again.
The scented gel or fluid typically is volatile—which is desired for an air freshener in order to generate odor—but, as a result, the scented fluid or gel often dissipates faster than desired. Evaporating too quickly results in too strong a scent being generated in the surrounding area and undesirably frequent replacement or refilling or replacement of the scented fluid or gel. Adjustable openings often are used to prevent too much odor from escaping the air freshener housing; however, this may not solve the problem of frequent refill or replacement.
BRIEF SUMMARY OF THE INVENTION
The present invention is directed toward devices and systems using electric lighting elements, light strings and lighted displays, and other lighted articles used not only to create a desired visual effect, but also to generate a desired scent during use. In particular, the invention is directed toward scented lampholders and to light strings and lighted displays incorporating scented lampholders. For the purpose of this disclosure, the term “lampholder” can be interpreted to include thy lamp base, the socket, and/or the socket base, depending on the construction of the particular lampholder.
In one disclosed embodiment, the invention is directed toward a lampholder having a body configured to be physically coupled to a lighting element and at least one electrical conductor such that the lighting element is operatively electrically coupled to the at least one conductor. At least part of the body is made from a material comprising a compound having a desired scent. The scented compound has an elevated rate of vaporization from the material when the lampholder is in a heated state due to being engaged with an illuminated lighting element. The elevated rate of vaporization is significantly greater than a reduced rate of vaporization of the scented compound from the material occurring when the lampholder is not in the heated state.
In another disclosed embodiment, the material comprises a compound having a desired scent and having a first rate of vaporization from the material when the lampholder is in a heated state due to being engaged with an illuminated lighting element. The first rate of vaporization is great enough that the desired scent can be noticed in the vicinity of the lampholder when the lampholder is operating. The scented compound has a second rate of vaporization from the material when the lampholder is not in the heated state. The second rate of vaporization is low enough that the desired scent is at least substantially unnoticeable in the vicinity of the lampholder when the lampholder is not operating.
The present invention is also directed toward methods of making such devices and systems. In one disclosed embodiment, a method for making a lampholder for a lighting display that generates a desired scent during operation includes the steps of combining a polymeric material and a scented compound to form a scented polymeric material having a desired scent; and forming the scented polymeric material into at least one lampholder part.
In another disclosed embodiment, a method for making a lampholder for a lighting display that generates a desired scent during operation includes the steps of melting a polymeric material to form a liquid polymeric material; adding a scented compound to the liquid polymeric material to form a liquid scented polymeric material having a desired scent; forming the liquid scented polymeric material into the shape of at least one lampholder part; and cooling liquid scented polymeric material until the lampholder part is solid.
The present invention is also directed toward lighting systems incorporating such lampholders.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)
In order to assist understanding of the present invention, embodiments will now be described, purely by way of non-limiting example, with reference to the attached drawings, in which:
FIG. 1 is an isometric view of a lampholder, a lighting element and a portion of a conductor, according to one illustrated embodiment of the present invention.
FIG. 2 is an exploded view of the lampholder, lighting element and portion of conductor of FIG. 1 .
FIG. 3 is an isometric view of a light string according to an illustrated embodiment of the present invention.
FIGS. 4A and 4B are isometric views of a pair of light displays according to an illustrated embodiment of the present invention.
FIG. 5 is a flow chart illustrating a method for making a lampholder according to one disclosed embodiment of the present invention.
FIG. 6 is a flow chart illustrating a method for making a lampholder according to one disclosed embodiment of the present invention.
FIG. 7 is a graph plotting the rate at which scented compound vaporizes from the plastic of the lampholder, as a function of the temperature of the plastic.
DETAILED DESCRIPTION OF THE INVENTION
The present invention is directed toward devices and systems for using electric lights, light strings and lighted displays, or other lighted articles, to generate a desired scent during use, and to methods of making such devices and systems. The following is a detailed description of a few illustrative embodiments. The drawings are provided to clarify the description, and may not be to scale.
FIG. 1 illustrates a light 10 for a light string, lighted display or the like. Atypical light 10 may be made up of a lighting element 12 and a lampholder 14 , which are coupled to a conductor 16 carrying many lights along its length.
As better illustrated in FIG. 2 , the lighting element 12 may be made up of a lamp 18 and a lamp base 20 ; and the lampholder 14 may be made up of a socket 22 and a socket base 24 . A pair of leads 26 on the lighting element 12 can be coupled to one or more wires in the conductor 16 via contacts in the lampholder 14 such that the bulb 18 illuminates when the conductor is energized. The inventor appreciates that some of these details can be modified without deviating from the spirit of the invention, and that an individual of ordinary skill in the art having reviewed this disclosure will appreciate modifications that could be made to the illustrated embodiment.
FIG. 3 illustrates a light string 28 according to one particular embodiment of the present invention. The illustrated light string 28 extends between a pair of electrical connectors 30 , and may contain 150 lighting elements 10 , 300 lighting elements, or any other number desired by the manufacturer. Likewise, the lighting elements 10 can be incandescent bulbs, clear or colored bulbs, flashing bulbs, or any other suitable bulb or lighting element. In addition, the light string 28 can be in the form of a single string, as illustrated; however, the inventor appreciates that swag lights, net lights and other configurations would also work with the present invention.
FIGS. 4A and 4B illustrate two particular lighted displays 32 according to disclosed embodiments of the present invention. The lighted display 32 can have a solid frame or planar substrate giving it a desired shape, such as the illustrated snowman and tree. One or more light strings 28 can be routed about and coupled to the frame or extended through the substrate, or can otherwise be coupled to the lighted display 32 . The lighted display 32 can be left uncovered, or can be covered with a layer of material to create a desired affect when the lighted display is illuminated.
In each of the above-described embodiments, the device or system incorporates a lampholder made from a material that generates a significant amount of a desired scent when the lighting element, light string or lighted display is operating, but does not generate a significant amount of the desired scent when the same is not operating. As reflected in FIG. 7 , the concentration of the scented compound is selected such that the rate the scent is generated “r o ” at operating temperature “t o ” is at or above the concentration sufficient for individuals in the vicinity of the lights to readily appreciate the scent “i.e., >A”, while the rate the scent is generated “r a ” at ambient temperature “t a ” during non-use is below the concentration necessary for individuals in the vicinity of the lights to readily appreciate the scent “i.e., <A”.
The particular scent selected for a particular device or system can complement the design of the lighted display, such as by using a pine scent for the lights on a tree or a peppermint scent for the lights on a candy cane, or can merely be an attractive scent, such as the scent of mulled spices on a Christmas-related display or the scent of pumpkin pie on a Thanksgiving-related display. An individual of ordinary skill in the art having reviewed this disclosure will appreciate the variations that could be made to these examples without deviating from the spirit of the invention.
FIG. 5 illustrates a method for making an article having a desired scent. The illustrated method begins with a polymeric material 34 and a scented compound 36 . The method then involves the step of combining 38 the polymeric material 34 and the scented compound 36 . The compounds may be combined in solid form (e.g. pellet, powder, etc.) or in liquid form, or a combination thereof (e.g. adding a powder to a liquid). The ratio of scented compound 36 to polymeric material 34 is selected to provide a desired amount of scent based on the use envisioned for the finished product (e.g. products for outdoor use may have more scented compound than equivalent products for indoor use).
Finally, the illustrated method involves forming 40 the scented polymeric material into a desired part. The part may be the lamp base 20 , the socket 22 and/or the socket base 24 . Again, an individual of ordinary skill in the art having reviewed this disclosure will appreciate how many parts to form from the scented polymeric material to obtain the desired amount of scent for a particular purpose, as more scented parts will obviously result in a stronger scent.
EXAMPLE 1
The inventor has practiced the present invention in several different ways, and provides herein a representative example of a method used to manufacture a scented device according to the present invention. In this particular example, the inventor used at least the following compounds: a resin, a fragrance diluter, a dispersing agent, a fragrance, a fragrance main agent, and an anti-oxidant. The procedure included the steps of: adding the fragrance to the fragrance diluter and stirring thoroughly; mixing in the dispersing agent, the anti-oxidant and the resin; and melting polypropylene pellets from an injection machine at a temperature between about 80˜120 Celsius. The flame retardant polypropylene and the fragrance main agent mix ratio is between about 8:1˜12:1 (ratio by weight). The pellets are then used to produce product by injection, as is generally understood in the art. An individual of ordinary skill in the art having reviewed this disclosure will appreciate that these compounds, ratios, temperatures and/or steps can be changed or supplemented without deviating from the spirit of the invention.
EXAMPLE 2
The inventor has practiced the present invention in several different ways, and provides herein another representative example of a method used to manufacture a scented device according to the present invention. In this particular example, the inventor mixed the flame retardant polypropylene with 1˜2% fragrance, and then produced the product by injection, as generally understood in the art. As these two non-limiting examples reflect, there are many specific methods that could be used to carry out the present invention, and the inventor intends that this patent cover all such methods, not merely the examples provided. As such, the inventor submits the following claims to reflect the scope of the invention, which should not be limited by the examples provided.
FIG. 6 illustrates a method for making scented lampholder parts according to another disclosed embodiment of the present invention. In this particular embodiment, the method begins by taking a polymeric material 42 and melting 44 the polymeric material. A scented compound 46 is added 48 to the melted polymeric material 42 . The method continues with the step of forming 50 the liquid scented polymeric material into one or more of the parts of the lampholder. Finally, the illustrated method incorporates the step of cooling 52 the scented polymeric material to fix it in the shape of the desired lampholder part. An individual of ordinary skill in the art having reviewed this disclosure will appreciate the details involved in carrying out this method, and will appreciate the additions and modifications that could be made to the method without deviating from the spirit of the invention.
From the foregoing it will be appreciated that, although specific embodiments of the invention have been described herein for purposes of illustration, various modifications may be made without deviating from the spirit and scope of the invention. Accordingly, the invention is not limited except as by the appended claims. | Lampholders formed from materials comprising scented compounds that are more volatile when warm than when at ambient temperature to generate a desired scent during use, along with lighted displays incorporating such lampholders and methods for making such lampholders, are shown and described. | 0 |
TECHNICAL FIELD OF THE INVENTION
The present invention is directed, in general, to wireless communication networks and, more specifically, to a system for providing reliable delivery of medium access control (MAC) messages over the air interface of a wireless communication network.
BACKGROUND OF THE INVENTION
Reliable predictions indicate that there will be over 300 million cellular telephone customers by the year 2000. Within the United States, cellular service is offered not only by dedicated cellular service providers, but also by the regional Bell companies, such as U.S. West, Bell Atlantic and Southwestern Bell, and the national long distance companies, such as AT&T and Sprint. The enhanced competition has driven the price of cellular service down to the point where it is affordable to a large segment of the population. As a result, wireless subscribers use a wide variety of wireless devices, including cellular phones, personal communication services (PCS) devices, and wireless modem-equipped personal computer (PCs), among others.
To maximize usage of the available bandwidth, a number of multiple access technologies have been implemented to allow more than one subscriber to communicate simultaneously in a wireless system. These multiple access technologies include time division multiple access (TDMA), frequency division multiple access (FDMA), and code division multiple access (CDMA). These technologies assign each system subscriber to a specific traffic channel that transmits and receives subscriber voice/data signals via a selected time slot, a selected frequency, a selected unique code, or a combination thereof.
Generally, a multiple access wireless system uses dedicated control channels to establish, to maintain, and to break down a connection between a subscriber's mobile device (also called “mobile unit” or “mobile station”) and the wireless system. The control channel signals transmitted between the base transceiver stations of the wireless system and the mobile units are generally referred to as medium access control (MAC) messages. The MAC layers of the base transceiver stations and the mobile units are the lower half of the data link layer that defines topology dependent access control protocols in a communication network. The MAC layer specifies the message frame formats as well as the conditions for accessing the traffic channels of the wireless network.
MAC messages are transmitted in a forward control channel from a base transceiver station to one or more mobile units and in a reverse control channel from the mobile station to the base transceiver station. At the start of a wireless telephone call or data transmission, the MAC messages establish a connection and assign the subscriber to a selected traffic channel. Once the connection is established, the subscriber and the base transceiver station exchange voice and/or data signals via the selected traffic channel. MAC messages are used to maintain the connection and to handle any hand-offs that are performed between base transceiver stations.
The performance and reliability of a wireless network is at least partially determined by the reliability with which MAC messages are exchanged between mobile units and base transceiver stations in the wireless network. If a MAC,message is lost in transmission or received out-of-sequence due to the loss of another MAC message, the wireless network typically must re-transmit at least one, and usually several, of the MAC messages in order to compensate for the one or more lost MAC messages.
There is therefore a need in the art for wireless networks that provide more reliable communications between mobile units and base transceiver stations in the wireless network. In particular, there is a need in the art for wireless networks that exchange MAC messages in a more reliable manner.
SUMMARY OF THE INVENTION
To address the above-discussed deficiencies of the prior art, it is a primary object of the present invention to provide, for use in a wireless communications device, a medium access control (MAC) message acknowledgment system for acknowledging MAC messages transmitted in an RF control channel between the wireless communications device and a remote communications unit. In one embodiment of the present invention, the MAC message acknowledgment system comprises a control processor capable of receiving an outbound MAC message unit from a MAC layer device in the wireless communications device and attaching a header to the outbound MAC message unit to thereby form an outbound MAC message suitable for transmission to the remote communications unit, the header comprising logic bits identifying the outbound MAC message unit to the remote communications device to thereby enable the remote communications unit to acknowledge receipt of the outbound MAC message.
In another embodiment of the present invention, the MAC message acknowledgment system further comprises a timer coupled to and controllable by the control processor, wherein the timer stores a delay period the MAC message acknowledgment system will wait before re-transmitting the outbound MAC message.
In still another embodiment of the present invention, the MAC message acknowledgment system further comprises a memory coupled to and controllable by the control processor, wherein the control processor stores the outbound MAC message in the memory if a receipt of a previously transmitted MAC message has not been acknowledged by the remote communications unit.
In yet another embodiment of the present invention, the wireless communications device is a mobile device.
In a further embodiment of the present invention, the wireless communications device is a base transceiver station in a wireless network.
In a yet further embodiment of the present invention, the control processor is capable of receiving from a transceiver an inbound MAC message transmitted by the remote communications unit.
In a still further embodiment of the present invention, the control processor detects an embedded header in the received inbound MAC message and uses the embedded header to acknowledge to the remote communications unit a receipt of an embedded MAC message unit in the received inbound MAC message.
In yet another embodiment of the present invention, the control processor modifies a header in a second outbound MAC message in order to acknowledge receipt of the received inbound MAC message.
The foregoing has outlined rather broadly the features and technical advantages of the present invention so that those skilled in the art may better understand the detailed description of the invention that follows. Additional features and advantages of the invention will be described hereinafter that form the subject of the claims of the invention. Those skilled in the art should appreciate that they may readily use the conception and the specific embodiment disclosed as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. Those skilled in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the invention in its broadest form.
Before undertaking the DETAILED DESCRIPTION, it may be advantageous to set forth definitions of certain words and phrases used throughout this patent document: the terms “include” and “comprise,” as well as derivatives thereof, mean inclusion without limitation; the term “or,” is inclusive, meaning and/or; the phrases “associated with” and “associated therewith,” as well as derivatives thereof, may mean to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, or the like; and the term “controller” means any device, system or part thereof that controls at least one operation, such a device may be implemented in hardware, firmware or software, or some combination of at least two of the same. It should be noted that the functionality associated with any particular controller may be centralized or distributed, whether locally or remotely. Definitions for certain words and phrases are provided throughout this patent document, those of ordinary skill in the art should understand that in many, if not most instances, such definitions apply to prior, as well as future uses of such defined words and phrases.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, wherein like numbers designate like objects, and in which:
FIG. 1 illustrates an exemplary wireless network according to one embodiment of the present invention;
FIG. 2 illustrates an exemplary MAC acknowledgment request systems in a base transceiver station and a mobile unit according to one embodiment of the present invention;
FIG. 3 illustrates an exemplary MAC message packet suitable for transmission between a base transceiver station and a mobile unit according to one embodiment of the present invention;
FIG. 4 is a flow diagram illustrating the operation of an exemplary MAC acknowledgment request system according to one embodiment of the present invention; and
FIG. 5 is a flow diagram 500 illustrating the operation of an exemplary MAC acknowledgment request system during receipt of a MAC message packet from another wireless device according to one embodiment of the present invention.
DETAILED DESCRIPTION
FIGS. 1 through 5, discussed below, and the various embodiments used to describe the principles of the present invention in this patent document are by way of illustration only and should not be construed in any way to limit the scope of the invention. Those skilled in the art will understand that the principles of the present invention may be implemented in any suitably arranged communications network.
FIG. 1 illustrates an exemplary wireless network 100 according to one embodiment of the present invention. The wireless telephone network 100 comprises a plurality of cell sites 121 - 123 , each containing one of the base transceiver stations, BTS 101 , BTS 102 , or BTS 103 . In a preferred embodiment of the present invention, the wireless telephone network 100 is a CDMA-based network. Base transceiver stations 101 - 103 are operable to communicate with a plurality of mobile units (M) 111 - 114 . Mobile units 111 - 114 may be any suitable cellular devices, including conventional cellular telephones, PCS handset devices, portable computers, metering devices, and the like.
Dotted lines show the approximate boundaries of the cells sites 121 - 123 in which base transceiver stations 101 - 103 are located. The cell sites are shown approximately circular for the purposes of illustration and explanation only. It should be clearly understood that the cell sites may have other shapes, such as hexagonal, depending on the cell configuration selected and natural and man-made obstructions.
BTS 101 , BTS 102 and BTS 103 transfer voice and data signals between each other and the public telephone system (not shown) via communications line 131 . Communications line 131 may be any suitable connection means, including a T 1 line, a T 3 line, a fiber optic link, a network backbone connection, and the like. In some embodiments, BTS 101 , BTS 102 and BTS 103 may be wirelessly linked to one another and/or the public telephone network by a satellite link.
In the exemplary wireless network 100 , mobile unit 111 is located in cell site 121 and is in communication with BTS 101 , mobile unit 113 is located in cell site 122 and is in communication with BTS 102 , and mobile unit 114 is located in cell site 123 and is in communication with BTS 103 . The mobile unit 112 is located in cell site 121 , close to the edge of cell site 123 . The mobile unit 112 towards cell site 123 . At some point as mobile unit 112 moves into cell site 123 and out of cell site 121 , a “handoff” will occur.
A “handoff” is a well-known process for transferring control of a call from a first cell to a second cell. For example, if mobile unit 112 is in communication with BTS 101 and senses that the signal from BTS 101 is becoming unacceptably weak, mobile 112 may then switch to a BTS that has a stronger signal, such as the signal transmitted by BTS 103 . Mobile unit 112 and BTS 103 establish a new communication link and a signal is sent to BTS 101 and the public telephone network to transfer the on-going voice and/or data signals through the BTS 103 . The call is thereby seamlessly transferred from BTS 101 to BTS 103 .
BTS 101 , BTS 102 , and BTS 103 transmit MAC messages in a forward control channel to the respective ones of mobile units 111 , 112 , 113 or 114 and receive MAC messages in a reverse control channel from the mobile units. The MAC messages are transmitted in MAC control channels and are used to establish, to maintain, and to break down the traffic channel communication links carrying the voice and/or data signals between the base transceiver stations and the mobile units. To ensure the reliability of the transfer of MAC messages between the base transceiver stations and the mobile units, MAC acknowledgment request systems in accordance with the principles of the present invention are implemented in both the base transceiver stations and the mobile units.
FIG. 2 illustrates exemplary MAC acknowledgment request systems 210 and 260 in base transceiver station 101 and mobile unit 112 according to one embodiment of the present invention. FIG. 3 illustrates an exemplary MAC message packet 300 suitable for transmission between base transceiver station 101 and mobile unit 112 according to one embodiment of the present invention. MAC message packet 300 , which may be either an outgoing or an incoming packet, comprises control field 301 , sequence number 302 , and MAC message unit (MMU) 303 , as explained below in greater detail. MAC acknowledgment request system 210 and 260 are responsible for reliably delivering MAC message packets between BTS 101 and mobile unit 112 . MAC messages may originate in MAC layers 201 and 251 of either mobile unit 112 or BTS 101 and are transferred to transceivers 230 and 280 for transmission.
MAC acknowledgment request system 210 in BTS 101 comprises MAC acknowledgment control processor 211 , timer 212 , and memory 213 . Memory 213 contains internal received sequence number (IRSN) 221 , internal sent sequence number (ISSN) 222 , send buffer 223 , and queue 225 . As explained below in greater detail, MAC acknowledgment request system 210 transfers MAC message units between the medium access control (MAC) layer 201 of BTS 101 and the transceiver system 230 of BTS 101 .
Mobile unit 112 is comprised of similar components. MAC acknowledgment request system 260 in mobile unit 112 comprises MAC acknowledgment control processor 261 , timer 262 , and memory 263 . Memory 263 contains internal received sequence number (IRSN) 271 , internal sent sequence number (ISSN) 272 , send buffer 273 , and queue 275 . MAC acknowledgment request system 260 transfers MAC message units between the medium access control (MAC) layer 251 of mobile unit 112 and the transceiver system 280 of mobile unit 112 .
MAC acknowledgment request system 210 and MAC acknowledgment request system 260 perform mirror image functions in BTS 101 and mobile unit 112 , respectively. This being the case, the operations of MAC acknowledgment request system 210 and MAC acknowledgment request system 260 are functionally identical. The operations of both systems can therefore be explained by explaining the operation of only one. For the sake of clarity and simplicity, the present invention will hereafter be explained principally, but not exclusively, in terms of the operation of MAC acknowledgment request system 210 . It will be understood by those skilled in the art, however, that these descriptions also apply to MAC acknowledgment request system 260 .
MAC acknowledgment request system 210 is an acknowledgment (ACK) based system that uses timer 212 to control the retransmission of MAC messages that are not acknowledged. In a preferred embodiment of the present invention, MAC acknowledgment request system 210 allows only one outstanding message (per instance) at any one time.
MAC acknowledgment control processor 211 , which controls the operations of MAC acknowledgment request system 210 , receives outgoing MAC message unit (MMU) 303 from MAC layer 201 . MMU 303 , whether incoming or outgoing, may contain a variable number of bits. MAC acknowledgment request system 210 attaches a header, comprising control field 301 and sequence number 302 , to outgoing MMU 303 , thus creating an outgoing MAC message packet similar to exemplary MAC message packet 300 in FIG. 3 . Outgoing MAC message packet 300 is then sent to transceiver system 230 for transmission to mobile unit 112 .
When MAC acknowledgment request system 210 receives incoming MAC message packet 300 from transceiver system 230 , MAC acknowledgment control processor 211 strips off the header and sends the resulting incoming MAC message unit 303 to MAC layer 201 .
In one embodiment of the present invention, the header consists of three (3) bits: a two-bit control field 301 and a one-bit sequence number 302 . MMU 303 may be a variable number of bits in length, however, in a preferred embodiment of the present invention, MMU 303 is twenty-one (21) bits long. MAC acknowledgment control processor 211 maintains a 1-bit internal received sequence number (IRSN) 221 in memory 213 that holds the sequence number 302 of the last incoming MMU 303 that was sent to MAC layer 201 . When MAC acknowledgment request system 210 receives incoming MAC message packet 300 containing incoming MMU 303 , MAC acknowledgment control processor 211 compares sequence number 302 of new incoming MMU 303 to IRSN 221 . Incoming MMU 303 is sent to MAC layer 201 only if sequence number 302 does not match IRSN 221 . In this manner, if MAC message packet 300 is retransmitted because of a lost acknowledgment message, the same MAC message packet 300 will not be sent twice to MAC layer 201 by receiving MAC acknowledgment request system 210 .
MAC acknowledgment control processor 211 also maintains a 1-bit internal sent sequence number (ISSN) 222 which indicates the sequence number 302 of the last message sent. In a preferred embodiment of the present invention of the present invention in which MAC acknowledgment request system 210 can have only one outstanding MAC message packet 300 at a time, a 1-bit sequence number 302 is sufficient to perform the foregoing operation. In alternate embodiments of the present invention, sequence number 302 may contain more than one bit in order to maintain a count of a larger number of outstanding MAC message packets 300 .
The value in control field 301 determines the meaning of MMU 303 in each MAC message packet 300 . A control field 301 value of “10” (binary) indicates to a receiving device that the current incoming MAC message packet 300 constitutes an acknowledgment from a transmitting device that the transmitting device has successfully received an MMU 303 previously transmitted by the receiving device and also indicates that the current incoming MAC message packet 300 does not contain a new incoming MMU 303 (the rest of MAC message packet 300 is padded with 0's)
A control field 301 value of “01” (binary) indicates to a receiving device that the current incoming MAC message packet 300 contains a new incoming MMU 303 , but does not constitute an acknowledgment of an MMU 303 previously transmitted by the receiving device.
A control field 301 value of “11” (binary) indicates to a receiving device that the current incoming MAC message packet 300 contains a new incoming MMU 303 and also constitutes an acknowledgment from a transmitting device that the transmitting device has successfully received an MMU 303 previously transmitted by the receiving device.
A control field 301 value of “00” (binary) is a reserved value.
In general, MAC acknowledgment request system 210 may send/receive two types of acknowledgments: an acknowledgment may be sent just by itself (a “pure” acknowledgment having control field 301 set to “10”), or it may be “piggybacked” with a new MMU 303 (control field 301 set to “11”). If the acknowledgment is piggybacked on a new MMU 303 , the sequence number 302 of the MAC message packet 300 refers to the sequence number 302 of the new MMU 303 .
Since MAC acknowledgment request system 210 may receive an outgoing MMU 303 from MAC layer 201 while it already has an outgoing MAC message packet 300 outstanding (i.e., waiting for an acknowledgment), MAC acknowledgment control processor 211 uses queue 225 to store each outgoing MMU 303 until it can be serviced. In addition, MAC acknowledgment control processor 211 uses send buffer 223 to store the current outgoing MAC message packet 300 (i.e., a MAC message packet 300 that has not been sent nor acknowledged yet). Finally, MAC acknowledgment request system 210 uses timer 212 to dictate retransmissions of outstanding MAC message packets 300 .
MAC acknowledgment request system 210 has two operating modes: Idle and Packet Outstanding. If MAC acknowledgment request system 210 is in Idle mode and receives an incoming MAC message packet 300 from transceiver 230 , MAC acknowledgment control processor 211 strips the header off the received packet and checks the sequence number 302 . If the sequence number 302 is different than IRSN 221 , the MAC message packet 300 is a new message and the incoming MMU 303 contained therein is sent to MAC layer 201 . IRSN 221 is then updated to be the sequence number 302 of the MAC message packet 300 just received.
If the sequence number 302 of the received MAC message packet 300 matches IRSN 221 , the MAC message packet 300 is a retransmission of a message packet that has already been successfully received in BTS 101 , and the MAC message packet 300 is discarded. The likely cause of the retransmission is the failure of mobile unit 112 to receive an acknowledgment of the first transmission of the message packet. ISSN 222 is not updated in this case.
In either case of the foregoing situations, MAC acknowledgment request system 210 sends a pure acknowledgment message (control field 301 =10) to transceiver 230 for transmission to mobile unit 112 .
If MAC acknowledgment request system 210 is in Idle mode and receives an outgoing MMU 303 from MAC layer 201 , it updates ISSN 222 (flips the bit), and copies this value into the sequence number 302 of the header for the outgoing MAC message packet 300 . Control field 301 of the header is set to “01” (no acknowledgment) After attaching the header to the outgoing MAC message packet 300 , MAC acknowledgment control processor 211 copies the outgoing MAC message packet 300 into send buffer 223 and sends the outgoing MAC message packet 300 to transceiver 230 for transmission. MAC acknowledgment control processor 211 then starts the retransmission timer 212 and transitions to the Packet Outstanding State.
If, while in Packet Outstanding State, MAC acknowledgment request system 210 receives another outgoing MMU 303 from MAC layer 201 , the outgoing MMU 303 is put in queue 225 . If the retransmission timer 212 expires while MAC acknowledgment request system 210 is in the Packet Outstanding State, MAC acknowledgment control processor 211 retrieves the outgoing MAC message packet 300 currently in send buffer 223 and sends it to transceiver 230 for retransmission. In some embodiments of the present invention, whenever timer 212 expires, a counter in memory 213 may be incremented and, if the counter exceeds a pre-determined system value, error recovery procedures are started (reset and initialization).
If MAC acknowledgment request system 210 receives an acknowledgment while in Packet Outstanding State, MAC acknowledgment request system 210 flushes send buffer 223 . Subsequent operations of MAC acknowledgment request system 210 depend on whether or not queue 225 is empty.
If queue 225 is empty, and MAC acknowledgment request system 210 receives a pure acknowledgment (control field 301 =10), MAC acknowledgment request system 210 transitions to the Idle State. If the acknowledgment was piggybacked on a new incoming MMU 303 (control field 301 =11), MAC acknowledgment control processor 211 strips the header off the incoming MAC message packet 300 and compares the sequence number 302 with IRSN 221 . If the sequence numbers do not match, the new incoming MMU 303 is sent to MAC layer 201 and IRSN 221 is updated (the bit is flipped). If the numbers match, the MAC message packet 300 is discarded. In either case, MAC acknowledgment request system 210 then sends a pure acknowledgment message (control field 301 =10) to transceiver 230 . MAC acknowledgment request system 210 then transitions to the Idle State.
If queue 225 is not empty, and MAC acknowledgment request system 210 receives a pure acknowledgment message (control field 301 =10), MAC acknowledgment control processor 211 retrieves the next outgoing MMU 303 from queue 225 . After updating ISSN 222 (flipping the bit), the sequence number 302 in the header is set to the value of ISSN 222 . Control field 301 is set to “01”, the new outgoing MAC message packet 300 is stored in send buffer 223 and sent to transceiver 230 , and timer 212 is reset.
If the acknowledgment was piggybacked on a new incoming MMU (control field 301 =11), MAC acknowledgment control processor 211 first processes the incoming MAC message packet 300 as described above. MAC acknowledgment control processor 211 then retrieves the next outgoing MMU 303 from queue 225 and processes it as above, except that control field 301 is set to “11”. The new outgoing MAC message packet 300 is stored in send buffer 223 and sent to transceiver 230 , and timer 212 is reset. MAC acknowledgment request system 210 remains in the Packet Outstanding State.
If, while in Packet Outstanding State, MAC acknowledgment request system 210 receives an incoming MAC message packet 300 that does not contain an acknowledgment, MAC acknowledgment control processor 211 strips the header from the incoming MAC message packet 300 and sends the incoming MMU 303 to MAC layer 201 (after checking sequence number 302 against IRSN 221 ). A pure MAC acknowledgment message (control field 301 =10) is then sent to transceiver 230 . No further action is taken in this case.
FIG. 4 is a flow diagram 400 illustrating the operation of an exemplary MAC acknowledgment request system 210 during receipt of an incoming MMU from MAC layer 201 according to one embodiment of the present invention. Both Idle mode and Packet Outstanding mode are depicted. While MAC acknowledgment request system 210 is in Idle mode, an MMU 303 is initially received from MAC layer 201 (process step 401 ). MAC acknowledgment request system 210 attaches a header to newly received MMU 303 and sets control field 301 to “01” (process step 402 ). Next, MAC acknowledgment request system 210 stores a copy of the outbound MAC message packet 300 in send buffer 223 (process step 403 ) and also sends the outbound MAC message packet 300 to transceiver 230 (process step 404 ).
MAC acknowledgment request system 210 then sets timer 212 to a predetermined system value that establishes the time period that MAC acknowledgment request system 210 will wait for a response to the outbound MAC message packet 300 (process step 405 ). Once the outbound MAC message packet has been passed to transceiver 230 , MAC acknowledgment request system 210 enters the Packet Outstanding mode.
While MAC acknowledgment request system 210 is in Packet Outstanding mode, an MMU 303 may be received from MAC layer 201 (process step 451 ). Because MAC acknowledgment request system 210 is still waiting to receive an acknowledgment message for the presently outstanding MAC message packet, the newly received MMU 303 is stored in queue 225 (process step 452 ). At this point, MAC acknowledgment request system 210 waits until an acknowledgment message is received from mobile unit 112 .
If an acknowledgment message only is received, MAC acknowledgment request system 210 takes the following actions. MAC acknowledgment request system 210 fetches MMU 303 from queue 225 , attaches a header with control field=“01”, updates ISSN 222 , and sets sequence number 302 equal to ISSN 222 . MAC acknowledgment request system 210 then stores a copy of the outbound MAC message packet 300 in send buffer 223 and sends the outbound MAC message packet 300 to transceiver 230 . Finally, MAC acknowledgment request system 210 sets timer 212 to wait for a response to the outbound MAC message packet 300 (process step 453 ).
If MAC acknowledgment request system 210 receives an acknowledgment message that also contains a new inbound MMU 303 from mobile unit 112 , MAC acknowledgment request system 210 takes the following actions. MAC acknowledgment request system 210 first processes the newly received inbound MMU 303 from mobile unit 112 as in FIG. 5 . Next, MAC acknowledgment request system 210 fetches the outbound MMU 303 from queue 225 and attaches a header with control field=“11”. MAC acknowledgment request system 210 then stores a copy of the outbound MAC message packet 300 in send buffer 223 and also sends the outbound MAC message packet 300 to transceiver 230 . Finally, MAC acknowledgment request system 210 sets timer 212 to establish the waiting period for a response acknowledgment from mobile unit 112 (process step 454 ).
While MAC acknowledgment request system 210 is in Packet Outstanding mode, timer 212 may expire (process step 455 ). MAC acknowledgment request system 210 responds by re-transmitting the outbound MAC message packet 300 in send buffer 223 (process step 456 ). MAC acknowledgment request system 210 then increments the error counter. If the error counter exceeds a maximum allowed value, error procedures are initiated (process step 457 ).
If an incoming MMU 303 is received without an acknowledgment message while MAC acknowledgment request system 210 is in Packet Outstanding mode, MAC acknowledgment request system 210 responds by sending back an acknowledgment message with control field 301 set to “10” and processes the incoming MMU 303 as in FIG. 5 (process step 458 ).
FIG. 5 is a flow diagram 500 illustrating the operation of an exemplary MAC acknowledgment request system 210 during reception of a MAC message packet 300 from mobile unit 112 according to one embodiment of the present invention. Initially, MAC acknowledgment request system 210 is in Idle mode. Idle mode is interrupted when MAC acknowledgment request system. 210 receives a MAC message packet 300 from transceiver 230 (process step 501 ). MAC acknowledgment request system 210 reads the header of the received MAC message packet 300 and compares the sequence number 302 therein to the IRSN 221 in memory 213 (process step 502 ).
If the sequence number 302 and IRSN 221 are different, MAC acknowledgment request system 210 sends the newly received MMU 303 to MAC layer 201 , and updates the value of IRSN 221 . MAC acknowledgment request system 210 then sends an acknowledgment message back to mobile unit 112 via transceiver 230 (process step 503 ). If the sequence number 302 and IRSN 221 are the same, MAC acknowledgment request system 210 discards the redundant MMU 303 and does not update IRSN 221 . MAC acknowledgment request system 210 then sends an acknowledgment message back to mobile unit 112 via transceiver 230 (process step 504 )
Although the present invention has been described in detail, those skilled in the art should understand that they can make various changes, substitutions and alterations herein without departing from the spirit and scope of the invention in its broadest form. | There is disclosed for use in a wireless communications device, a medium access control (MAC) message acknowledgment system for acknowledging MAC messages transmitted in an RF control channel between the wireless communications device and a remote communications unit. The MAC message acknowledgment system comprises a control processor capable of receiving an outbound MAC message unit from a MAC layer device in the wireless communications device and attaching a header to the outbound MAC message unit to thereby form an outbound MAC message suitable for transmission to the remote communications unit, the header comprising logic bits identifying the outbound MAC message unit to the remote communications device to thereby enable the remote communications unit to acknowledge receipt of the outbound MAC message. | 7 |
ORIGIN OF THE INVENTION
The invention described herein was made in the performance of work under a NASA Contract and is subject to the provisions of Section 305 of the National Aeronautics and Space Act of 1958, Public Law 85-568 (72 STAT. 435; 42 U.S.C. 2457).
BACKGROUND OF THE INVENTION
The invention generally relates to solid electrolyte cells and more particularly to an improved solid electrolyte cell having strips of platinum defining electrodes extended along opposite side surfaces of the cell in mutually spaced parallelism and defining therebetween parallel strips of bare substrate surfaces which tend to offer minimal resistance to gas flow, whereby the electrical resistance for the cell is lowered and the gas conductivity thereof enhanced.
DESCRIPTION OF THE PRIOR ART
Use of solid electrolyte cells generally is well known in the separation of oxygen from compounds such as carbon dioxide, and the disassociation of water into oxygen and hydrogen, as well as in fuel cells for production of electricity from a recombination of oxygen and hydrogen.
As is also well known, the operation of a solid electrolyte cell is based on its capabilities for conducting ions when either an electrical potential is applied thereacross, or a difference of partial pressures of oxygen is caused to exist at the two sides of the solid electrolyte. In either case, it is necessary that the opposite surfaces of the solid electrolyte be electrically connected so that an ionic current can be established between the opposite side surfaces, through the body of solid electrolyte.
The ionic current is, of course, made up of oxygen ions which enter the solid electrolyte at the interface of the so-called negative surface and exit at the interface of the so-called positive surface, as determined by the polarity of the applied voltage.
The amount of ionic current that can be caused to flow through a solid electrolyte with a given total voltage drop is a function of the resistance of the electrodes attached to or plated on the opposite surfaces of the body of electrolyte. Electrodes for solid electrolyte cells of the type aforementioned, conventionally have been made of platinum deposited on the surfaces of the body of solid electrolyte as a film and then fired. Heretofore, it has been required that the film be porous sufficiently as to be gas conductive. To insure an existence of the required porosity, the film generally must be applied as a relatively thin film. Unfortunately, the electrical resistance of the electrodes thus is increased. Conversely, where attempts have been made to increase the mass of electrodes, for thereby reducing electrical resistivity, increased resistance to gas flow at the surface interfaces is encountered. Hence, those engaged in the design of electrolyte cells have for a long while been plagued with the attendant design problems arising from these competing design parameters. It is therefore, the general purpose of the instant invention to provide an improved solid electrolyte cell, having enhanced electrical conductivity without an attendant increase in gas-flow resistance.
During the course of a search conducted for the instant invention, the patents discovered are listed on the enclosed "List Of Prior Art Cited By Applicant".
Of the patents listed on the enclosed sheet, it is believed that U.S. Pat. No. 3,115,702 to Scutt probably is the most pertinent reference discovered during the course of the search, aforementioned. This patent discloses an electrolytic process in which water is split into hydrogen and oxygen. Based upon the realization that the electrode in the process does not have to be made entirely of platinum, but that the platinum has to cover only a fraction of the total electrode surface, the patentee suggests the use of a composite electrode consisting of a refractory base metal, such as titanium, niobium or zirconium and an inlaid noble metal such as platinum or a platinum based alloy in which the noble metal was added for cathodic protection of the anode. It is important to note that the platinum is not utilized in forming the electrode but has been added to the base metal electrode for protection. Moreover, the size and configuration of the platinum strips has no effect on electrolytic operation of the cell and no gasses have to cross a solid barrier at the interface. In other words, the teachings of this patent suggest a lowering of the total usage of noble metal cladding by leaving bare base metal surfaces exposed without an attendant deterioration of the base metal.
OBJECTS AND SUMMARY OF THE INVENTION
It is an object of the instant invention to provide an improved solid electrolyte cell.
It is another object to provide an improved solid electrolyte cell having platinum electrodes deposited on opposite side surfaces of a solid electrolyte body in a manner such that enhanced electrical conductivity is facilitated without an attendant reduction in the cell's capability of accommodating gaseous currents of ions through the body.
It is another object to provide in a solid electrolyte cell, a body of electrolyte material having opposed surfaces, each defining a substrate for a plurality of electrodes, said body being characterized by paths for ionic currents extended between the opposed surfaces of the body, a multiplicity of elongated, mutually spaced electrodes deposited on each of said surfaces and having defined therebetween elongated strips of substrate surfaces exposed to the ambient environment for the cell, whereby an increased electrical flow is accommodated without an increased resistance to ionic currents flowing between the electrodes at the opposite surfaces of the body.
These and other objects and advantages are achieved by depositing on the opposite surfaces of a body of electrolyte material a plurality of mutually spaced bar-shaped electrodes arranged in parallelism for defining therebetween strips of substrate exposed to the ambient environment for the cell.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partially sectioned, schematic view of a solid electrolyte cell, seated in a heater utilized for stabilizing the temperature of the cell.
FIG. 2 is a partially sectioned, fragmented view, but on an enlarged scale, of the cell shown in FIG. 1.
FIG. 3 is a cross-sectional view of the cell taken generally along lines 3--3 of FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, with more particularity, wherein like reference characters designate like or corresponding parts throughout the several views, there is shown in FIG. 1, an electrolyte cell, generally designated 10, embodying the principles of the instant invention.
It is here important to appreciate that the invention relates primarily to the construction of electrodes for the cell 10 and that the cell 10 is equally useful in processes in which a separation of oxygen from carbon dioxide, and in the disassociation of water into oxygen and hydrogen, or, for that matter, in a fuel cell for producing electricity through a recombination of oxygen and hydrogen. Therefore, the purpose, particular environment, and/or the particular process in which the solid electrolyte cell 10 of the instant invention is employed forms no particular part of the invention hereinafter more specifically described and claimed.
As shown in the drawings, however, the solid electrolyte cell 10 is formed of an ionized gas-conductive material of a tubular configuration, having one end closed and connected at its opposite end through a suitable fitting 12 to an oxygen-gas receiver, also not shown. Furthermore, as shown, the cell 10 is seated in a clam-shell heater 14, the purpose of which is to control the temperature of the cell. Again, since the particular environment in which the cell 10 is employed is of no particular consequence, a detailed description of the heater 14 is omitted in the interest of brevity.
It therefore suffices to say that the cell 10, as shown, is connected to communicate with a source of oxygen-bearing gas, such as CO 2 , through the fitting 43 and is seated in a conduit 43' mated with a sleeve 16, provided for coupling purposes. It is to be understood that the conduit is suitable for conducting CO 2 to the external surface of the cell 10 and is connected in an hermetically sealed relation therewith. A suitable union 18, also forming no part of the invention hereinafter described and claimed, is provided for connecting the sleeve 16 with the fitting 12.
Referring now for a moment to FIG. 2, it can be seen that the electrolyte cell 10 comprises a body 20 of solid electrolyte having an elongated tubular configuration closed at its end, designated 22. The opposite end of the body 20 is connected in communication with the fitting 12 through a length of tubing 24, formed of a material such as Inconel 600, extended through this union 18 and inserted axially into the body 20. The body 20 is inserted into a length of tubing 26, also formed of Inconel 600, which is in turn hermetically sealed, through the use of hermetic seals 28, within the sleeve 16.
As shown in the drawings, the body 20 includes an external surface 30 and an internal surface 32, both being of a cylindrical configuration and arranged in mutually concentric relation. The material from which the body 20 is formed comprises a ceramic ionized gas-conducting material, such as, for example, eight percent yttria stabilized zirconia, the purpose of which is to accommodate an establishment of a plurality of flow paths for ionic currents extending between the surfaces 30 and 32.
Deposited on the external surface 30 of the body 20 is a plurality of mutually spaced electrodes 34, of bar-like configurations. These electrodes are arranged in parallelism with the longitudinal axis of the body 20, and are commonly connected through contact with the length of tubing 26. As a practical matter, the tubing 26 functions as a common contact or bus bar for the electrodes 34.
Deposited on the internal surface 32 of the body 20, is a plurality of mutually spaced, bar-like electrodes 36. The electrodes resemble the electrodes 34 in size and shape and extend in parallelism with the longitudinal axis of the body 20. As a practical matter, the electrodes 34, as well as the electrodes 36, define therebetween bare strips 38 of substrate surfaces, whereby the body 20 is exposed at its opposite surfaces to ambient environments, both internally and externally.
The particular manner in which the electrodes 34 and 36 are deposited on the surface of the body 20 also forms no part of the instant invention. It suffices to say that the number of bare strips 38 of substrate, or body surface, for the electrodes 34 and 36, and the width thereof is determined by manufacturing limitations. However, the optimum effect is achieved by having the largest numbers of electrodes found possible, under practical constraints, with the smallest widths found possible. Thus, both the electrodes 34 and 36 are arranged to conduct a flow of electron current in parallelism with the longitudinal axis of the body.
As aforementioned, the electrodes 34 are commonly connected with the tubing 26. The electrodes 36, however, are commonly connected with the length of tubing 24. Since the lengths of tubing 24 and 26 are formed of electrical conducting material, such as Inconel 600, these lengths of tubing not only afford structural strength but additionally serve as bus bars for the electrodes extended along the surfaces of the body 20.
In order to establish an electric field across the cross-sections of the body 20, a first lead 40 is connected, by welding, or the like, to the length of tubing 26, while a further lead 42 is connected to the length of tubing 24, also as by welding or the like. The leads 40 and 42 are, preferably, connected to the opposite sides of a voltage source in order to establish an electrostatic field across the electrolyte forming the body 20.
OPERATION
It is believed that in view of the foregoing description, the operation of the device will readily be understood, however it will be briefly reviewed at this point.
With the solid electrolyte cell embodying the principles of the instant invention assembled in the manner hereinbefore described, it is a simple matter to initiate its operation. When connected with a source of gas, such as CO 2 , through the fitting 43, the CO 2 gas is introduced to flow along the exterior surface of the body 20, via the length of tubing 16. With an electrostatic field established across the body of solid electrolyte, the CO 2 is exposed to the bare strips 30 of substrate surfaces, as found to exist between the electrodes 34. These electrodes, as a practical matter, function as cathodes. Thus oxygen crosses the solid barrier at the interface of ambient environment, causing an ionic flow of oxygen to be established along a plurality of paths extending from the electrodes 34 to the electrodes 36. The electrodes 36, of course, function as anodes. Consequently, the CO 2 is broken down as the oxygen ions flow through the body 20 to the internal surface or bare strips 38 existing between the electrodes 36. At this surface, the ions recombine to form O 2 which is, where so desired, conducted away from the solid electrolyte cell 10 via the conduit, connected with the sleeve 24.
In view of the foregoing, it is believed to be readily apparent that the solid electrolyte cell which embodies the principles of the instant invention provides a practical solution to the problems heretofore encountered in attempting to enhance electron flow without an attendant reduction in ionic flow through a solid electrolyte body. | A solid electrolyte cell including a body of solid ionized gas-conductive electrolyte 20 having mutually spaced surfaces 30 and 32 on which is deposited a multiplicity of mutually spaced electrodes 34 and 36, having strips 30 and 32 of bare substances interposed between electrodes, so that currents of ionic gas may be established between the electrodes via the bare strips 30 and 32, whereby electrical resistance for the cells is lowered and the gas conductivity thereof is enhanced. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Patent Application Serial. No. 60/039,430, filed on Feb. 26, 1997, and entitled “Combined DSL/Channel Bank”.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention generally relates to telecommunications and, more particularly, to an apparatus and method for combining POTS and DSL apparatus and function into one device. The combination uses a single highspeed CODEC which samples both the POTS signal and the DSL signal.
2. Description of the Invention
As known in the art, high-speed modems are able to transfer data at high rates over a local loop. In order to accomplish these high data rates, the high-speed digital modems use frequencies which are significantly higher than the voice band frequencies used in the plain old telephone system (“POTS”).
However, such modems require that the central office wire center utilize a POTS splitter device to separate the POTS voice band frequencies, occurring in the frequency spectrum between about 0 Hz and about 4 kHz, from the highspeed digital modem data using the frequency spectrum of between about 20 kHz and about 1 MHz. This setup also requires that there be duplicative hardware to process the POTS voice and digital modem frequencies. The hardware converts the voice data into digital data for transmission over a voice time division multiplexing (TDM) bus, and the digital signal that is processed by analog front end and coder/decoder (CODEC) devices converts the highspeed modem data from the analog frequencies back to digital data. Unfortunately, the manufacture and installation of POTS filters and duplicative coder/decoder and analog front end logic are expensive and their use sometimes requires the rewiring of the central office wire center.
Consequently, it would be desirable to avoid the use of the POTS splitter and duplicative analog front-end and coder/decoder logic, which saves space due to the reduced circuitry and avoids the expense the extra circuitry imposes.
SUMMARY OF THE INVENTION
Certain objects, advantages and novel features of the invention will be set forth in part in the description that follows and in part will become apparent to those skilled in the art upon examination of the following or may be learned with the practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
To achieve the advantages and novel features, the present invention is generally directed to a central office data communications apparatus and method, that allows a combined voice POTS and high speed modem processing functions into one device at the central office. The combination of the signals allows for a single high-speed CODEC which samples both a POTS signal and the high-speed modem signals to be utilized. This eliminates the need for external POTS splitters and costly duplicative circuitry.
One embodiment of the modem apparatus and method for a combined digital subscriber line (DSL) and voice system includes apparatus for processing the voice POTS signals and the speed modem signals through a common analog front end high-speed coder/decoder (CODEC) circuitry. The digital signals from the high-speed CODEC are provided to a DSP logic which provides for support of multiple voice lines. Once connected, voice POTS frequencies are not bursty, and therefore, need to be serviced on an eight kHz sample rate in both directions. The digital signal processor (DSP) provides this processing by filtering between voice and high speed modem data in the DSP itself.
The preferred embodiment includes a sample rate of 192 kHz. However, any sample rate is possible as long as it is a multiple of the eight kHz, because the voice POTS signal is always sampled at an eight kHz rate in order to interface to the public switched telephone network (PSTN) network. Since the conversion and filtering between voice and high speed modem data is not run time extensive, the DSP can service multiple subscriber lines simultaneously without saturation.
The invention can also be viewed as providing a method for allowing combined voice POTS and high speed modem processing functions in one device. In this regard, the method can be broadly summarized by the following steps:
interfacing to a local loop capable of simultaneously carrying both a POTS signal and high speed modem signals;
sampling both said POTS and said high speed modem signals with a single codec; and
processing both said sampled POTS and said sampled modem signals.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings incorporated in and forming a part of the specification illustrate several aspects of the present invention, and together with the description, serve to explain the principles of the invention. In the drawings:
FIG. 1 is a schematic view of the central office (CO) wire centers and user premises layout.
FIG. 2 is a block diagram of the CO POTS interface, the POTS switch analog conversion card and the DSL modem apparatuses of FIG. 1 .
FIG. 3 is a schematic view of the CO wire centers and user premises layout with the modem bank, that combines the central office DSL modem and the POTS switch analog conversion card for voice data signals, apparatus of the present invention.
FIG. 4 is a block diagram of the modem bank of FIG. 3 .
FIG. 5 is a block diagram of the analog front end and subscriber line interface circuit, and the coder/decoder circuit of FIG. 4 .
FIG. 6 is a block diagram of the digital signal processor engine of FIG. 4 .
Reference will now be made in detail to the description of the invention as illustrated in the drawings. While the invention will be described in connection with these drawings, there is no intent to limit it to the embodiment or embodiments disclosed therein. On the contrary, the intent is to cover all alternatives, modifications, and equivalents included within the spirit and scope of the invention as defined by the appended claims.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now in detail to the drawings in which the reference numerals indicate like parts throughout several views, FIG. 1 illustrates the plain old telephone system (POTS) networks including data communication modems ( 16 and 45 ) of the prior art. The POTS network includes numerous user premises 41 , wherein each user premises is connected to a central office wire center 11 , via a subscriber line 27 . Each subscriber line 27 is connected to the user premises 41 , which further connects to a user premises line 47 , for distribution of POTS service throughout the user premises. Usually, there are numerous POTS devices connected to each user premises line 47 , such as telephones 44 , fax machines 42 , PCs 43 , and the like. It is also known, but not shown, that it is possible to have multiple subscriber lines 27 connected to each user premises, thereby creating two separate user premises lines 47 within each user premises.
As noted previously, each user premises is connected via a subscriber line 27 to a central office wire center 11 . The subscriber line 27 is connected to a POTS splitter device 15 that separates the analog POTS signals from data signals. The POTS signals are sent to a POTS switch 14 that is connected to the other central office wire centers, via the public switched telephone network (PSTN) 28 . Modem data signals are separated from the POTS analog signals at POTS splitter 15 , and are connected to modems 16 within the central office wire center 11 . Modems 16 are further connected to digital data networks such as the Internet 29 .
A brief discussion of an example for the signals generated in the applied system environment for the prior art from the user premises and transmitted through the central office wire center, via either the PSTN or Internet networks and back to a user premises will now be detailed.
When a user wishes to place a telephone call on device 44 , the user picks up the receiver and puts the subscriber line 27 in an off-hook condition that is detected at the central office wire center 11 , by closed switch hooks (not shown). The off-hook condition signals the central office wire center 11 , via subscriber line 27 , to accept an outgoing call by allowing a flow of D.C. current and a dial tone of 480 Hz to be sent to device 44 . The outgoing telephone call signals are transmitted, as described before, via subscriber line 27 to POTS splitter 15 . The analog POTS system signals are separated from the modem signals, and the POTS signals are directed towards the POTS switch 14 for transmission, via the PSTN network 28 , to the destination central office wire center 11 of the destination user premises 41 . The signal is further directed towards a POTS splitter 15 within the destination central office wire center 11 . The signal is transmitted, via subscriber line 27 , to the destination user premises 41 . The modem signal enters the destination user premises 41 , via subscriber line 27 , and is connected to the user premises line 47 that distributes the signal to be received throughout the destination user premises 41 . This is the path in which a plain old telephone system (POTS) call is transmitted.
Now, a description of digital signals to/from the user premises will be described. When a user desires to transmit data over a digital network via his personal PC 46 , digital phone 44 , or the like, the digital signals from the digital device, are transformed into analog signals, via modulation by modem 45 . The signals are transmitted over the user premises line 47 to the subscriber line 27 for final delivery to the local central office wire center 11 . The digitally modulated analog signals going into POTS splitter 15 , are separated from the analog POTS signals, and are directed to modems 16 . Modems 16 demodulate the analog signals back to their original digital data signals. The modems 16 transmit the digital data over the Internet 29 . The digital data signals sent via the Internet 29 are received at the destination central office wire center 11 by the modems 16 . The modems 16 modulate the digital signals into analog signals for transmission through the POTS splitter 15 and over destination subscriber line 27 to the destination user premises 41 . The modulated signals are received at the user premises line 47 , for distribution to all equipment connected to the user premises distribution line. The modulated signals are demodulated, within the destination modem 45 , back to a digital signals, which are transmitted to the digital device connected to the modem.
FIG. 2 illustrates the separate central office POTS interface, the POTS Switch analog conversion card, and the DSL modem apparatuses of the prior art.
The POTS splitter device 15 illustrated in FIG. 2 is connected to the subscriber line wire pair 27 which transmits both voice POTS and high-speed modem data into the central wire office 11 . The POTS splitter device separates the low voice POTS frequency spectrum of 0 kHz to 4 kHz and transmits them as described above to POTS switch 14 . The POTS switch 14 contains within it a voice line card 32 , comprising the subscriber line interface circuit 33 and CODEC 34 .
The CODEC 34 converts the analog voice signals into digital signals and transmits them, via the voice TDM bus 21 , across the PSTN network 28 to the destination central office wire center for transmission to the destination user premise 41 , as described above. The high-speed digital modem signals on the subscriber line wire pair 27 are separated from the voice signals and provided to a modem device 16 for processing.
The modem device 16 comprises an analog front end 35 , which transforms the two wire high speed analog data signals, utilizing the frequency spectrum of between about 20 kHz and 1 MHz into four wire loops, and transmits the analog signals over the four wire loops to the CODEC device 36 for conversion from analog signals into digital data. The high-speed digital data is then output from the CODEC 36 into the DSP digital signal processor (DSP) 37 logic for processing and further transmission via the digital data bus ( 22 ). As can be seen by FIG. 2, there is duplicate hardware in both the POTS switch 14 and the modem 16 devices which include the analog front end 35 and subscriber link interface circuit 33 , and the CODEC 34 and 36 devices.
FIG. 3 illustrates the plain old telephone system (POTS) networks including data communication modem and voice bank 60 of the present invention. It is shown that the present invention communication modem bank 60 can be substituted for the POTS splitter 15 and high-speed data modem 16 . The network is otherwise the same.
Referring now to FIG. 4, illustrated is a block diagram of the modem bank 60 that combines the voice POTS and high-speed modem data functionality into one device. The modem and voice bank 60 utilizes a single analog front end/subscriber link interface (AFE/SLIC) circuit 61 to interface to the subscriber link 27 which is connecte d to the user premise 41 . The AFE/SLIC 61 herein defined in further detail with regard to FIG. 5 provides for the hybrid circuits, ring indicator, off/hook detector, and line protection circuitry. The AFE/SLIC 61 , by utilizing the hybrid circuit, provides for a one way analog communication link for a signal in each direction on lines 67 A and 67 B. This a nalog signal is transmitted between the AFE/SLIC 61 and the CODEC 62 . The CODEC 62 herein defined in further detail with regard to FIG. 5 provides the actual coding of digital to analog signals and decoding of analog to digital signals. The digital signals from CODEC 62 are transmitted between the CODEC 62 are the DSP logic 63 across bus 75 . Bus 75 provides a multiplexing of digital signals from one of a plurality of operating CODECs 62 to the DSP logic 63 at any particular time. The DSP logic 63 , herein defined in further detail with regard to FIG. 6, processes the digital data received from line 75 and filters out the voice POTS signals from the digital data signals.
The DSP logic 63 then transmits the voice POTS signals to the POTS switch 14 (FIG. 3) for transmission across the PSTN network 28 to the destination central office wire center 11 POTS switch 14 . The digital data is filtered and transmitted on data bus 25 , and over the Internet 29 to the destination CO wire center 11 . DSP logic 63 is herein defined in further detail with regard to FIG. 6 .
Since it is assumed that DSP sharing is provided, multiple AFE/SLICs 61 and CODECs 62 can share the processing power of the DSP logic 63 which can support numerous simultaneous transmissions through the central office wire center. The DSP sharing includes voice sharing which assumes that the voice has a low peak busy hour rate, probably lower than data due to shorter hold times. Once connected, the voice signal is not bursty, therefore, it needs to be serviced on an eight kHz sample rate in both directions. This can be done because the voice processing, which converts 12 bit linear code into eight bit mu-law code, is done in this DSP logic 63 and is not run time extensive. Filtering between the voice signals and data signals is also done in DSP logic 63 , eliminating the need for a separate POTS filter.
Referring now to FIG. 5, illustrated is shown the AFE/SLIC 61 and the CODEC 62 functional block diagram. The subscriber line 27 is a bidirectional wire pair from the subscriber user premise 41 and is connected to a line protection circuitry 65 . Line protection circuit 65 protects the multi-channel communications device against line surges, lightening strikes and the like. Line protection circuit 65 is then further connected to the impedance and isolation circuit 66 via a communication link. The impedance and isolation circuit 66 contains circuitry for impedance control, isolation, hybrid circuits, ring indicator and off-hook detector (not shown). The AFE/SLIC 61 is then connected via communication link 67 to the CODEC 62 .
With further reference to FIG. 5, CODEC 62 receives analog signals via line 67 A for conversion from analog to digital receiver circuit 72 . Analog to digital receiver 72 is provided timing by timing circuit 71 . Timing circuit 71 provides timing signals to process the analog to digital and digital to analog transformations. The output of the analog to digital receiver 72 is digitized data which is placed on bi-directional bus 75 .
Digital communication link 75 and 25 can be comprised of 8 , 16 , 32 , 64 , 128 or other bit sized digital parallel communication link. Communication link 25 and 75 can also be comprised of a bit serial or other type of chip to chip signal communication links. Communication link 67 B transmits analog signals coded by the digital to analog driver 73 . The digital to analog driver 73 receives digital signals for transmission across digital communication link 75 .
Interface 68 carries the control and status information from the digital signal processor to the impedance control isolation circuitry 66 of AFE/SLIC circuitry 61 .
Referring now to FIG. 6, illustrated is the DSP 63 block diagram of the functionality of the DSP logic 63 . Digital signals are received on communication link 75 and are provided to the data demodulator 81 and to the decimator 82 . For the voice POTS signals, the decimator 82 reduces the voice sample rate to eight kHz. The signal is then sent through a low pass filter 83 which eliminates the high frequency data signals. A linear to mu-law converter 84 converts the voice signals for output onto a voice time division multiplexing (TDM) bus 21 . The voice POTS signal is combined with voice signals from other channels to make up the TDM bus. The digital demodulator 81 receives the high speed digital signals from the CODEC 62 , demodulates these signals, and transmits them across data bus 22 for further transmission over the Internet 29 .
The transmit path through the DSP logic 63 has the data modulator 86 receiving high speed digital data signals from the data bus 22 . The voice TDM bus 21 provides a digitized voice signal to the mu-law to linear converter 85 . The mu-law to linear converter 85 provides for encoding of the digitized voice POTS signal. In an alternative embodiment, A-law encoding may be utilized instead of mu-law encoding. The encoded voice POTS signal is then added to the data signal output from the data modulator 86 in circuitry 87 . The voice POTS signal is summed on an eight kHz sample rate while the combined voice and data signal is outputted to the digital to analog converter on a multiple of eight kHz sample rate.
The preferred embodiment provides for the sample rate to be 192K. The above description provides for operation of a single voice and data channel. Other embodiments include multiple AFE/SLIC 61 and multiple CODEC 62 s (as shown in FIG. 4) and provides the ability to be active at the same time through DSP sharing using statistical properties of data as described in the U.S. Pat. No. 6,084,885 entitled “APPARATUS AND METHOD FOR DSP SHARING USING STATISTICAL PROPERTIES OF DATA”, Ser. No. 09/027,705 herein incorporated by reference.
The foregoing description has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Obvious modifications or variations are possible in light of the above teachings. The embodiment or embodiments discussed were chosen and described to provide the best illustration of the principles of the invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly and legally entitled. | Apparatus and method for a central office data communications apparatus allows for combining the voice POTS and high speed modem data processing functions into one device at the central office. The combination of the signals allows for a single high-speed CODEC which samples both a POTS signal and the high-speed modem signals to be utilized. This eliminates the need for external POTS splitters and costly duplicative circuitry. | 7 |
FIELD OF THE INVENTION
The invention relates to the recovery of natural gas from natural gas wells and more particularly concerns an apparatus for reducing the critical velocity required to unload extended perforated intervals in liquid-loaded gas wells.
BACKGROUND OF THE INVENTION
FIG. 1 illustrates a production tubing string 13 deployed in a cased natural gas wellbore 101 having an extended perforated interval 102 . The production rate of a natural gas well is a function of the pressure differential between the underground reservoir and the well head. This differential is decreased by back pressure against the reservoir pressure. As natural gas and associated liquids are extracted during production, a gradual loss of reservoir pressure occurs in some natural gas wells, thus decreasing the pressure differential. Natural gas wells produce liquids such as water and hydrocarbon. Removal of these produced liquids depends on the velocity of the gas stream produced from the formation. As reservoir pressure and flow potential decrease, there is a corresponding drop in the flow velocity of the natural gas through the production tubing to the well head. Eventually, when the flow velocity becomes insufficient to overcome the “fall back” velocity of the liquids, a column of liquids accumulates in the well bore. This phenomenon referred to as liquid loading decreases the production of the well because the weight of the fluid column above the producing formation causes additional back pressure, which the reservoir must overcome. The critical velocity is the flow velocity or flow rate(mcf/d) required to overcome this pressure differential needed to lift produced fluids to surface.
FIG. 2 illustrates one of the methods that have been used in the art to overcome the problem of liquid loading. Production tubing 13 is extended to include a ported tubing section 17 and a “dead string” 14 . Ported tubing section 17 can be a length of production tubing, for example one joint of production tubing or a smaller length of tubing i.e., a pup joint, having holes 18 drilled therein. The inner diameter (ID) of production tubing section 13 and the ID of dead string 14 are isolated from each other by plug 15 . Alternatively, this design can include a “bull plug” on the bottom of dead string 14 to force the flow up to the ported section 17 . Thus, fluids do not flow through the ID of dead string 14 . Rather, the function of dead string 14 is to decrease the area of the annular space 106 between the dead string and the face of the wellbore (or casing). During operation, gas and formation fluids 11 in perforated interval 102 flow in the annular region 106 around dead string 14 . Dead string 14 typically has a larger outer diameter (OD) than production tubing section 13 , though the dead string 14 can also be the same size as the production tubing 13 . For example, in a well with 4½″ casing having an ID of 4″, the production string might have an OD of 2⅜″ and the dead string might have an OD of 2⅞″. Dead string 14 reduces the flow area in the perforated interval, thereby decreasing the required flow rates (critical velocities) to lift produced liquid in the wellbore to surface and reduce the effects of liquid loading. Formation fluids and gas 11 cross over into the production tubing section 13 via holes 18 in ported tubing section 17 .
Perforated regions of a gas well often produce sand, which can stick to the tubing (i.e., to dead string 14 inside the casing), fill the tubing, or fill the wellbore below the dead string 14 . Several actions that well operators would typically perform to diagnose and correct these sand problems are not possible with the apparatus illustrated in FIG. 2 . and other dead string installations or designs known in the art. For example, plug 15 isolating the dead string from the production string (or a permanent “bull plug” on the bottom of dead string 14 , as mentioned above) prevents an operator from accessing the wellbore below the apparatus. Thus the operator lacks the ability to run a wireline to the bottom of the wellbore to check for sand fill levels below the dead string 14 . Also, when a tubing string becomes stuck in sand or when the bottom of tubing string becomes filled with sand, i.e., “sanded in,” an operator typically tries to establish fluid flow to the bottom of the tubing string and back up through the annular region to disengage the string from the sand. This operation is not possible with the configuration illustrated in FIG. 2 because the holes in 17 can not be isolated and the bull plug would prevents the ability to get circulation fluids to the bottom of the production tubing.
Another deficiency in the configuration illustrated in FIG. 2 is that perforated tubing section 17 limits an operator's ability run fluid down the annular region between the tubing and the casing to the bottom of the wellbore because such fluids would tend to cross over into the ID of the tubing via holes 18 . Thus, the configuration illustrated in FIG. 2 severely limits an operator's ability to access regions of the wellbore below plug 15 , for example, to deliver chemical foamer to the end of the dead string.
SUMMARY OF THE INVENTION
The presently disclosed apparatus provides a dead string for reducing the critical velocity of gas produced in a perforated interval of a gas well while still providing the well operator with the ability to access the well bore below the dead string. The apparatus features a tubing string extending into the gas well and having a ported member co-axially disposed within the tubing string. Typical ported members include sliding sleeve valves or ported flow subs, which are described in more detail below. The ported member will typically be positioned at the top of or in the top third of the perforated interval. The ported member is configured to selectively permit or prevent fluid communication between the interior of the ported member and the annular region between the tubing string and a wall of the well. When the ported member is open, fluids and gasses can enter the tubing string from the annulus via ports in the ported member. Alternatively, the ports can be closed to allow fluids to be run through the ported member to sections of the tubing string below the ported member.
The apparatus includes a retrievable plug disposed within the tubing string below the ported member. Typically, when the plug is in place, fluid flow will be entering the tubing string from the annulus via the ported member and flowing toward the surface in the tubing string. However, should an operator wish to run fluids or equipment (wireline equipment, etc.) down the string below the plug, the operator simply removes the plug to access lower regions of the string because the dead string is open ended below the plug.
The apparatus also includes a dead string co-axially disposed in the tubing string below the retrievable plug. Flow between the dead string and the upper part of the tubing string is blocked by the retrievable plug. Thus, the dead string operates simply to decrease the flow area of the annulus and thereby decrease the critical velocity of gas produced in the perforated interval. However, an operator can access the dead string by removing the retrievable plug.
Embodiments of the apparatus are also configured to deliver reagents such as foamers and/or surfactants to the extended perforated interval. For example, capillary tubing can be attached to tubing string to provide a conduit for such reagents. A valve or inlet such as a gas lift mandrel or injection sub can provide a crossover of the reagents from the capillary tubing to the inside of tubing string. According to one embodiment, the retrievable plug is configured to be moved either above or below the depth where reagent is delivered into the tubing string. Further aspects and advantages of the presently disclosed apparatus will be apparent in view of the figures and description below.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a length of production tubing string deployed in a cased natural gas wellbore having a perforated interval, as is common in the prior art.
FIG. 2 illustrates a prior art configuration of a dead string attached to a production string.
FIG. 3 illustrates a production string having a ported member, a retrievable plug, and a dead string.
FIG. 4 illustrates a ported flow sub having configured to engage an isolation tool.
FIG. 5 illustrates a production string having a ported member, a retrievable plug, and a dead string, exteriorly banded capillary tubing, and a gas lift valve.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 3 illustrates an embodiment of the presently disclosed apparatus. The apparatus 100 can be deployed in a cased wellbore 101 having a perforated interval 102 . Apparatus 100 includes a production tubing section 103 and a dead string 104 . The inner diameter (ID) of production tubing section 103 and the ID of dead string 104 are isolated from each other by retrievable plug 105 . During operation, gas and formation fluids in perforated interval 102 flow in the annular region 106 around dead string 104 . Dead string 104 typically has a larger outer diameter (OD) than production tubing section 103 but could be the same size as the production tubing. For example, in a well with 4½″ casing having an ID of 4″, the production string might have an OD of 2⅜″ and the dead string might have an OD of 2⅞″. Dead string 104 reduces the flow area in the perforated interval, thereby decreasing the critical velocity needed to lift produced liquids in the wellbore reducing the effects of liquid loading. It is often preferable that the couplings used for dead string 104 be configured flush with the profile of the OD of the dead string and not have external collars, etc., which cause accumulation sites for sand and particulate in the wellbore. Such “Ultra Flush Joint” pipe is known in the art. A particularly suitable joint is the ULTRA-FJ, available from Weatherford International, Inc. (Houston, Tex.). Additionally, various sizes of coil tubing are known in the art and can be used.
Fluids and gas flows upward in annular region 106 and cross over into the production tubing section 103 via ported member 107 through ports, which provide fluid communication between the inside and outside of the ported member. According to a one embodiment, ported member 107 is configured such that ports 108 can be closed, i.e., so that fluid communication between the inside and the outside of ported member 107 can be selectively permitted or prevented. Ported member 107 can be, for example, a sliding sleeve valve, as is known in the art. When the sliding sleeve valve is open, formation fluids can enter the ID production tubing via ports in the valve. Likewise, the valve can be closed, thereby isolating the valve.
According to an alternative embodiment, a ported member 107 can be a ported flow sub instead of a sliding sleeve valve. An example of a ported flow sub is schematically illustrated in FIG. 4 . Ported flow sub 201 is configured to integrate into a production stream via threaded ends 202 and 203 and its simplest embodiment is a length of tubing having ports 204 disposed therein. A ported flow sub 201 typically provides greater flow area than is available with a sliding sleeve valve. Flow sub 201 can include an isolation tool 205 for closing off ports 204 . Isolation tool 205 is a tubular member that is configured to fit within the ID of flow sub 201 as depicted by dashed line 206 . Isolation tool 205 can be designed to lockingly engage within flow sub 201 , for example, via locking mechanism 207 , which is configured to engage mating receiver 208 on flow sub 201 . The isolation tool illustrated in FIG. 3 also features a seal ring packing 209 that is configured to seal within a polished bore 210 in flow sub 201 . When isolation tool 205 is inserted in flow sub 201 it effectively isolates ports 204 and provides a flow path through the inner diameter 211 of the isolation tool. Thus, an operator can deliver fluids down the production tube to regions of the production tube below the ported flow sub bypassing ports 204 . A particularly suitable ported member is a Heavy Duty Flow Sub (Weatherford International, Inc., Houston, Tex.), which is compatible with a locking isolation tool as described above.
The presently disclosed apparatus provides an advantage over previous dead string assemblies because plug 105 is a retrievable plug and thus can be removed to provide an operator access to the tubing string below the plug. Retrievable plugs are known in the art. A particularly suitable retrievable plug assembly is a WX Nipple with a retrievable equalizing plug (Weatherford International, Inc., Houston, Tex.).
To check for sand fill in the wellbore below the apparatus illustrated in FIG. 2 , an operator can remove retrievable plug 105 and run a wire line down the tubing. The wire line can exit the bottom of the dead string and continue to the bottom of the well. According to one embodiment, the end of the dead string can include a wire line re-entry guide to assist in pulling the wire line tools back up into the dead string. If sand levels are acceptable, retrievable plug 105 is simply reinstalled and the system is immediately operational.
If dead string 104 is sanded in, an operator can try. to establish circulation down the tubing and back up the annulus while pulling or jarring on the production tubing string. To do this, the operator would typically shut off ports 108 , for example by installing an isolation tool as described above if ported member 107 is a ported flow sub. The operator can then deliver fluid to the bottom of the dead string while attempting to free the dead string.
According to one embodiment, the apparatus can include a safety release mechanism such as a shear-out joint, for example, between the removable plug 105 and the dead string 104 . Such a mechanism provides the operator the option to shear off and pull out the tubing, ported member, and plug assembly, should the previously described correction attempts fail. The operator simply applies adequate tension to tubing string to shear the tubing string at the shear-out joint and removes the string components above the joint. The operator can then recover the component(s) below the shear-out joint (namely, dead string 104 ) via fishing operations known in the art.
Another method commonly used in the art for overcoming liquid loading injection of reagents, such as foamers and/or surfactants into the perforated interval to decrease the surface tension and density of the liquid column. Typically, one would run a small diameter tubing line for delivering the chemical down through the production tubing to the desired depth, for example, out the end of the production tube. However, this method is not possible with the dead string assembly illustrated in FIG. 2 because plug 15 or the bull plug on the end of the dead string essentially isolates the string and well-bore below the plug. The embodiment of the presently disclosed apparatus illustrated in FIG. 5 overcomes this limitation of the prior art. This embodiment includes capillary tubing 301 or a side string banded to the OD of the tubing string and connecting to a gas lift mandrel 302 or injection sub installed in the tubing string below removable plug 105 . This embodiment provides the ability to deliver reagents, such as foamers, surfactants, etc. to the perforated interval 102 (shown in FIG. 1 ). The gas lift mandrel is installed below retrievable plug 105 so that such reagents can be injected into dead string 104 via inlet 303 , rather than being routed back up the production tubing. The reagents will be injected into the top of dead string 104 and can then fall through the ID of the dead string and into perforated interval 102 .
An alternative to banding capillary tubing or a side string to the OD of the tubing string is running the capillary tubing inside the production tubing to a modified nipple where the plug would normally be. This would allow the dead string assembly to be “snubbed” into the hole and still allow an operator the ability to get soap to the bottom of the dead string. This would limit the ability to run plunger lift, as discussed below.
The apparatus can include nipples configured to receive retrievable plug 105 below inlet 303 , rather than above inlet 303 as illustrated in FIG. 5 because in some situations it might be desirable to remove retrievable plug 105 and reinstall it below inlet 303 . For example, if the perforated interval does not generate sufficient gas to generate foam in the annular region around dead string 104 , the operator can reinstall plug 105 below inlet 303 and inject foamer into the production tubing below ported member 107 . Typically, the apparatus will be installed in the wellbore so that ported member 107 is at or near the top third of the perforated interval. There will typically be enough turbulence due to gas entering the production tubing via ported member 107 to generate foam.
According to an additional embodiment, a plunger lift system can be installed in the production tubing above ported member 107 . Plunger lift systems are known in the art and need not be explained in detail here, other than to mention that they are typically implemented in conventional systems, such as illustrated in FIG. 1 , wherein the production tubing terminates at the top of the perforated interval or in roughly the top third of a perforated interval. The effectiveness of plunger lift systems suffers if the tubing terminates too high above or too deep within the perforated interval. In the presently disclosed apparatus, a plunger lift system can be installed in the production tubing above ported member 107 . In such a configuration, ported member 107 is analogous to the terminus of the production tubing in a conventional system and is typically disposed at the top of or within the top third of the perforated interval for optimum plunger lift operation.
It should be understood that the inventive concepts disclosed herein are capable of many modifications. To the extent such modifications fall within the scope of the appended claims and their equivalents, they are intended to be covered by this patent. | Disclosed herein is a system for enhancing the recovery of gas in a perforated interval of a gas well. The system features a tubing string having a dead string attached for reducing the flow area of the annulus in the perforated interval, thereby reducing the critical velocity of the gas, i.e., the velocity required to overcome backpressure due to fluids in the well column. The system includes a ported member for receiving gas from the annulus into the tubing string. The ported member and the dead string are isolated from each other by a retrievable plug. The disclosed system provides access from the surface through the dead string for diagnostic or corrective operations. The system also provides delivery of reagents such as foamers to the perforated region to further reduce the critical velocity. | 4 |
THE FIELD OF THE ART
The present invention relates to saccharide-modified polymers which are useful as carriers capable of migrating into target organs (cells), drug-containing polymers using them and the process for the preparation thereof.
BACKGROUND
The drug delivery systems into the target organs comprising low-molecular drugs bonded to high-molecular compounds as carriers capable of migrating into target organs have been studied in order to obtain the aimed pharmaceutical effect of the drugs on the target organs and to reduce the side effects of the drugs on the other organs.
For example, it is disclosed that drug delivery systems into liver comprising of drugs modified with the compounds obtained by combination of galactose and proteins or high-molecule compounds based on the fact that the receptors specific for galactose exist in liver parenchymal cell in High-Molecule Vol. 46, No. 11, 843-848 (1997).
In addition, it is disclosed that poly-L-glutamic acid derivatives wherein a part of or all of the consisting peptide bonds in the poly-L-glutamic acid of the formula
(wherein, Xa is degree of polymerization of 20˜540, R a is hydrogen, lower alkyl or benzyl.) are replaced with a group of the formula
is useful as a carrier of drugs capable of migrating into liver in the Japanese Patent Application Kokai Hei 7-228688. The drugs have been conjugated to carboxyl group in the said glutamic acid via amide bond, ester bond or ion bond etc. directly. Vitamin K5 is described as an example of drugs in this publication.
Further, it is disclosed that polymers of PGE 1 -containing L-glutamic acid derivative (abbreviated as polymer PA) of the formula
is as high-molecule prodrug of PGE 1 capable of migrating into liver in International. J. Pharmaceutics, 155, 65-74 (1997). The drug (PGE 1 ) is conjugated to L-glutamic acid via amide bond through ethylenediamine (—NH—CH 2 CH 2 —NH—) as a spacer.
In the process for the preparation of the said polymer PA, which comprises amidation by condensation between PGE 1 and ethylenediamine as a spacer (reacting the activated ester of PGE 1 with ethylenediamine using carbodiimide (CDI) etc.), the reaction was carried out in an alkaline condition. Therefore, there is a problem that the drug which is unstable in an alkaline condition (e.g. PGE 1 ) would be decomposed and that the introducing rate of drugs into poly-L-glutamic acid does not increase. In this publication, quantity of drugs (PGE 1 ) introduced into one molecule of polymer (degree of polymerization of L-glutamic acid=101) is 1.6 molecule.
The present inventors have dissolved such a problem by using hydrazine (—NH—NH—) instead of ethylenediamine (—NH—CH 2 CH 2 —NH—) as a spacer in the reaction of drugs (e.g. PGE 1 ) and L-glutamic acid. That is to say, the reaction to introduce the drugs (PGE 1 ) is carried out in a weak acidic condition, so it is possible to introduce the drugs constantly, even if it is unstable in an alkaline condition. Based on this reaction, they have improved the introducing rate of drugs (e.g. PGE 1 ) into poly-L-glutamic acid, and then succeeded in synthesis of drugs-containing polymers showing the superior effect. In addition, it has proved that any compounds can be introduced into the polymer constantly by using this reaction. For example, quantity of drugs (PGE 1 ) introduced into one molecule polymer of the present invention (degree of polymerization of L-glutamic acid=97) is 5 molecule, which means the polymer of the present invention has 3-folds superiority in introducing rate of drug to compare with the polymer of the said publication.
In addition, the polymer using hydrazine of the present invention shows superiority in both accumulation of drugs into liver after administration and effects of drugs (cytoprotective activity of PGE 1 ) to the polymers using ethylelendiamine.
Further, there is a merit that such a reaction between hydrazine and the drug (PGE 1 ) has been carried out by a simple procedure comprising of only stirring them at room temperature.
DISCLOSURE OF THE INVENTION
The present invention relates to
(1) the polymer (abbreviated as Polymer P1.) wherein a part of or all of the consisting peptide bonds in the poly-L-glutamic acid of the formula (A)
(wherein, degree of polymerization d is 20˜500, R is hydrogen, C1˜6 alkyl or benzyl, with the proviso that each multiple R may be same or different.)
are replaced with a group of the formula
wherein
(wherein, G is a modified saccharide capable of conjugating to hydrazine))
as essential substituents with the proviso that when the number of replacement groups of the formula (C) is 2 or more, all of said groups are the same,
(2) the polymer (abbreviated as Polymer P2) wherein a part of or all of the peptide bonds in the poly-L-glutamic acid of the formula (A)
(wherein, all the symbols are defined as hereinbefore)
(wherein,
is defined as hereinbefore,
(wherein, D is a drug))
with the proviso that (1) groups of both the formula (C) and (D) are essential substituents, (2) when the number of replacement groups of the formula (C) or (D) is 2 or more, all of said groups of the formula (C) or (D) are the same and (3) the number of replacement groups of the formula (B) may be 0), and (3) the process for the preparation thereof.
DETAILED DESCRIPTION OF THE INVENTION
Polymer P1 is a carrier polymer capable of migrating into target organs (cells) and Polymer P2 is a drug-containing polymer, which is obtained by utilizing the said carrier polymer, capable of migrating into target organs (cells).
The delivery of the polymer of the present invention into target organs (cells) depends upon the saccharide (represented by G) conjugated to glutamic acid. It is known that various kinds of receptors for saccharides exist in organs (cells) and, new receptors may be found in the future study. It is possible to obtain the drug delivery system into target organs (cells) by choice of saccharide (G) capable of conjugating to the aimed organs (cells) including such known or new receptors.
For example, in case of monosaccharide, galactose receptor, mannose receptor and fucose receptor exist in liver parenchymal cells, liver nonparenchymal cells (endotherial cells and Kupffer cells) and Kupffer cells, respectively, so it is possible to obtain drug delivery system into liver (the said liver cells) by conjugate of galactose, mannose or fucose derivative (corresponds to Polymer P1 and P2 of the present invention in which
is a group of the formula of (G 1 ), (G 2 ) and (G 3 ) described hereinafter.). For example, in case of oligosacchardies such as di, tri or tetrasaccharides etc. or multi-saccharides, the delivery of the polymer of the present invention into target organs (cells) depends upon the terminal saccharide. For example, the terminal saccharide of lactose which is one of disaccharide (corresponds to Polymer P1 and P2 of the present invention in which
is a group of the formula (G 4a ) and (G 5a ).) is galactose, so such a polymer migrates into liver parenchymal cell mainly. As for the aimed saccharide, natural ones or artificial ones which are synthesized may be used.
The symbols and degree of polymerization etc. of Polymer P1 and P2 of the present invention are explained in detail as follows:
The symbol d in the formula (A) in Polymer P1 and P2 of the present invention means the degree of polymerization of L-glutamic acid which is a unit of the polymer of the present invention and it is an integer of 20˜500, preferably 40˜300 and more preferably 50˜150.
The number of replacement of group of the formula (B) in Polymer P1 (corresponds to y 2 described hereinafter.) is 5˜250 and preferably 5˜50.
The number of replacement of group of the formula (C) (corresponds to z 2 described hereinafter.) is 10˜100, and preferably 20˜60.
The number of replacement of group of the formula (B) in Polymer P2 (corresponds to y 3 described hereinafter.) is 0˜250, and preferably 0˜50.
The number of replacement of group of the formula (C) (corresponds to Z 3 described hereinafter.) is 10˜100, and preferably 20˜60. The number of replacement of group of the formula (D) (corresponds to W 3 described hereinafter.) is 1˜20, and preferably 1˜10.
The average of molecule weight of Polymer P1 is 5,000˜150,000. For example, the average of molecule weight of Polymer P1 using monosaccharide
is a group of the formula (G 1 ), (G 2 ) and (G 3 ) described hereinafter.) or disaccharide such as lactose derivative
is a group of the formula (G 4a ) and (G 5a ) described hereinafter.) is 5,000˜100,000 and preferably 10,000˜30,000.
C1-6 alkyl in the formula (A) in Polymer P1 and P2 means methyl, ethyl, propyl, butyl, pentyl or hexyl or its isomer.
Each R is preferably, i) hydrogen or the said C1˜6 alkyl (when multiple R are alkyl, they are the same.), ii) hydrogen or benzyl, or iii) hydrogen only, and more preferably, iii) hydrogen only.
The sacchardie represented by G in the formula (C) in Polymer P1 and P2 may be selected in accordance with the receptors which are know or may be found in the future study exist in the organs (cells), as mentioned before. The modified saccharides represented by G capable of conjugating to hydrazine include, for example, 2-iminoethyl-1-thiosaccharide derivatives and saccharides comprising a group wherein the linkage is cleaved etc.
The said 2-iminoethyl-1-thiosaccharide derivative represented by G include, for example, a group of the formula (if it is represented by
In addition, the said saccharide containing a group, wherein the linkage is cleaved, represented by G include, for example, group of the formula (if it is represented by
(wherein, Q is a saccharide chain containing 1˜10 of saccharide.).
Further, 1˜10 of saccharide represented by Q in the above formula include, for example, the saccharide of the formula
(wherein, each p, q and r is 0 or an integer of 1˜9.), preferably galactose, mannose and fucose (corresponds to a group in which each p, q, r is 0 in the above formula) and more preferably galactose.
is preferably a group of the formula
and more preferably group of the formula (G 1 ), (G 4a ) and (G 5a ).
In Polymer P2, glutamic acid and drugs represented by D is conjugated via various kinds of bonds such as hydorazon bond or amide bond etc. through hydrazino (—NH—NH 2 ) which is introduced to L-glutamic acid in accordance with the structure of drugs.
The drugs represented by D included any drugs, and preferably, the drug which is unstable in an alkaline condition. Such an alkaline condition means pH8˜11 preferably. Of course, it is possible to apply the drugs other than ones which are unstable in an alkaline condition.
Concrete drugs include PGs (e.g. PGEs, PGFs, PGDs), PGIs, naphthyloxyacetic acid derivatives, bicycloalkanoic acid derivatives, guanidinobenzoic acid derivatives, rhodanine acetic acid derivatives, cinnamoic acid derivatives, valproic acid derivatives, Vitamins, anti-allergic agents, anti-vital, anti-cancer agents etc.
PGs include natural PG such as PGE 1 , PGE 2 , PGF 1α , PGF 2α , PGD 1 , PGD 2 etc. and its derivatives.
For example, natural PGE 1 and PGE 2 are the compounds shown by the following structures, respectively:
and PGD 1 and PGD 2 are the compounds shown by the following structures, respectively:
The concrete PGs include the compounds of the following formula
(wherein,
is
R c is hydrogen or various kinds of substituents of carboxyl group such as C1˜12 alkyl, benzyl etc.,
A is C2˜10 alkylene (1) in which optional carbon atom may be replaced with CO and/or (2) may have one or more double bond(s),
B is C1˜10 alkyl, C2˜10 alkenyl or C2˜10 alkynyl may be substituted with phenyl, phenoxy or cycloalkyl (wherein each ring may be substituted with C1˜6 alkyl, C2˜6 alkenyl, C2˜6 alkynyl, C1˜6 alkoxy or halogen etc.),
is ethylene, trans-vinylene or ethynylene.).
PGs include preferably PGEs or PGDs (the compounds of the formula
in the above formula), more preferably PGEs (the compounds of the formula
in the above formula).
Such compounds include
PGE 1 , PGE 2 , 17,20-dimethyl-trans-Δ 2 -PGE 1 , 6-keto-17,20-dimethyl-trans-Δ 2 -PGE 1 methyl ester, 16,16-dimethyl-trans-Δ 2 -PGE 1 methyl ester etc.
PGEs and PGDs may be conjugated to L-glutamic acid via hydorazon bond at the 9th and 11th position carbon, respectively. For example, PGE 1 may be conjugated to L-glutamic acid as shown as following structure:
In addition, PGFs may be conjugated to L-glutamic acid via amide bond between the carboxyl group and amine group of hydrazine which is introduced.
PGIs include natural PGI 2 and its derivatives, for example, the compounds disclosed in Japanese Patent Application Kokai Sho 54-130543 and Sho 55-64541 (corresponding to GBP-2017699). PGls may be conjugated to L-glutamic acid via amide bond.
Naphthyloxyacetic acid derivatives include, for example, the compounds disclosed in Japanese Patent Application Kokai Hei 6-87811 (corresponding to U.S. Pat. No. 5,480,998), for example, [5-[2-[1-phenyl-(3-pyridyl)methylildenaminooxy]ethyl]-7,8-dihydronahthalene-1-yloxy]acetic acid shown by the formula
Such a naphthyloxyacetic acid compound may be conjugated to L-glutamic acid via amide bond at the terminal amino group of hydrazine as shown by the following structure:
Bicycloalkanoic acid derivatives include, for example, the compounds disclosed in Japanese Patent Application Hei 9-140959 (corresponding to Japanese Patent Application Kokai Hei 11-29548).
Guanidinobenzoic acid derivatives include, for example, the compounds disclosed in Japanese Patent Application Kokai Sho 51-138642 (corresponding to U.S. Pat. No. 4,021,472).
Rhodanine acetic acid derivatives include, for example, the compounds disclosed in Japanese Patent Application Kokai Sho 57-40478 (corresponding to U.S. Pat. No. 4,464,382).
Cinnamoic acid derivatives include, for example, the compounds disclosed in 1) Japanese Patent Application Kokai Sho 55-313 (corresponding to U.S. Pat. No. 4,226,878), 2) Japanese Patent Application Kokai Sho 57-131769 (corresponding to U.S. Pat. No. 4,607,046) and 3) WO 98/27053.
Valproic acid derivatives include, for example, the compounds disclosed in Japanese Patent Application Kokai Hei 7-316092 (corresponding to EP-0632008A1).
[The Process for the Preparation of the Polymer of the Present Invention]
The polymer of the present invention may be prepared by the method described hereinafter in Examples, known methods or the method of the following reactions (1)˜(3).
(1) introducing of hydrazine to poly-L-glutamic acid,
(2) introducing of saccharide (corresponds to G),
(3) introducing of drugs (corresponds to D).
In the reaction (1), poly-L-glutamic acid of the formula (A)
(wherein, all the symbols are defined as hereinbefore.)
is reacted with hydrazine shown by the formula NH 2 —NH 2 in an organic solvent such as dimethylformadmide (DMF) etc. or without solvent at room temperature (10˜25° C.) to prepare the polymer of the formula (II)
(wherein, d 1 , x 1 and y 1 are mol (degree of polymerization) of L-glutamic acid connecting COOR 1 (wherein, R 1 is C1˜6 alkyl or benzyl), L-glutamic acid connecting COOH and L-glutamic acid connecting NH 2 , respectively. With the proviso that, (1) sum of d 1 , x 1 and y 1 equals to d, (2) d 1 may be 0, (3) each L-glutamic acid connecting COOR 1 (wherein, R 1 is defined as hereinbefore.), COOH and NH 2 may be bonded at random in order.) (see the method described in J. Appl. Biochem., 2: 25 (1980)).
In the reaction (2), for example, saccharide (G) may be conjugated to hydrazine in the polymer of the formula (II) described hereinafter
(a) by reacting the polymer of the formula (II)
(wherein, all the symbols are defined as hereinbefore.)
and 2-imino-2-methoxyethyl-1-thiosaccharide in a weak alkaline condition (e.g. in borate buffer solution (pH9˜10)) or
(b) by reacting the polymer of the formula (II) and various kinds of saccharides, and then followed by reduction, if optionally.
2-Imino-2-methoxyethyl-1-thiosaccharide which is the starting material in the reaction (a) include, for example, 2-imino-2-methoxyethyl-1-thiogalactoside, 2-imino-2-methoxyethyl-1-thiomanoside or 2-imino-2-methoxyethyl-1-thiofucoside of the formula
2-Imino-2-methoxyethyl-1-thiosaccharide is known compound or may be prepared by reacting cyanomethyl-1-thiosaccharide and sodium methoxide in methanol at room temperature (10˜25° C.). (see the method described in Biochemistry Vol.15, No.18, 3956-3962 (1976)).
The saccharide which is starting material in reaction (b) include, for example, the compound of the formula
(wherein, Q is defined as hereinbefore.).
The polymer of the present invention wherein the formula
(wherein, Q is defined as hereinbefore.)
may be prepared by reacting aldehyde at the reductive terminal group of glucose of the saccharide which is used in the reaction and hydrazine in the polymer of the formula (II). This reaction is carried out in a weak acidic condition (e.g. in citrate buffer solution (pH4˜6)) at room temperature (10˜25° C.).
And then, the polymer of the present invention wherein the formula
(wherein, Q is defined as hereinbefore.)
may be prepared by reduction, if optionally.
This reduction is called as reductive amidation. It may be carried out using reductive agent such as sodium borohydride, sodium cyanoborohydride etc. in a weak alkaline condition (e.g. in borate buffer solution (pH8˜9)), at 30˜50° C. By the same procedure, an ordinal saccharide may be conjugated to hydrazine.
By the known reaction other than the above (a) and (b), saccharide (G) may be conjugated to hydrazine in the polymer of the formula (II).
By the series of the above reactions, the polymer of the present invention (corresponds to the said polymer P1) of the formula (I-1)
(wherein, d 2 , x 2 , y 2 and z 2 are mol (degree of polymerization) of L-glutamic acid connecting COOR 1 (wherein, R 1 is defined as hereinbefore.), L-glutamic acid connecting COOH, L-glutamic acid connecting NH 2 and L-glutamic acid connecting G (saccharide), respectively. With the proviso that (1) sum of d 2 , x 2 , y 2 and z 2 equals to d, (2) d 2 may be 0, (3) each L-glutamic acid connecting COOR 1 (wherein, R 1 is defined as hereinbefore), L-glutamic acid COOH, L-glutamic acid NH 2 and L-glutamic acid G (saccharide) may be connected at random in order.) may be prepared.
In reaction (3), various kinds of reactions will be carried out in accordance with the structure of drugs.
1) Drugs possessing keto group (—CO—) may be conjugated via hydorazon bond which is formed by dehydro-condensation reaction with hydrazine in the polymer of the formula (I-1). This reaction is carried out in a weak acidic condition (e.g. in citrate buffer solution (pH4˜6)), at room temperature (10˜25° C.).
2) Drugs possessing carboxyl group (—COOH) may be conjugated via amide bond which is formed by amidation with amino group at the terminal of hydrazine in the polymer of the formula (I-1). This reaction is well known, it may be carried out, for example,
(1) by the method with using acid halide,
(2) by the method with using mixed acid anhydride,
(3) by the method with using conducing agent (EDC and DCC etc.).
3) Besides the above, drugs may be introduced to poly-L-glutamic acid via various kinds of bonds by known method.
And then, NH 2 in hydrazine in the group may be capped with saccharide by reacting the polymer prepared in reaction (3) and the same saccharide as introduced in the reaction (2) again, if optionally.
The drug-containing polymer of the present invention (corresponds to Polymer P2) of the formula (I-2)
(wherein, d 3 , x 3 , y 3 , z 3 and w 3 are mol (degree of polymerization) of L-glutamic acid connecting COOR 1 (wherein, R 1 is defined as hereinbefore.), L-glutamic acid connecting COOH, L-glutamic acid connecting NH 2 , L-glutamic acid connecting G (saccharide) and L-glutamic acid connecting D(drug). With the proviso that (1) the sum of d 3 , x 3 , y 3 , z 3 and w 3 equals to d, (2) d 3 and y 3 , independently, may be 0, (3) L-glutamic acid connecting COOR 1 (wherein, R 1 is defined as hereinbefore.), COOH, NH 2 , G (saccharide) and D (drug) may be conjugated at random in order.) may be prepared by series of these reactions.
In each reaction in the present specification, obtained products may be purified by conventional techniques. For example, purification may be carried out by distillation at atmospheric or reduced pressure, by high performance liquid chromatography, by thin layer chromatography or by column chromatography using silica gel or magnesium silicate, by washing or by recrystallization. Purification may be carried out after each reaction, or after a series of reactions.
[Starting Materials and Reagents]
The starting materials and reagents in the present invention are known per se or may be prepared by known methods.
Industrial Applicability
It has been confirmed that the polymer of the present invention represented as Polymer P1 possesses capability of migrating into target organs as shown hereinafter in Experiment. It is expected that the said polymer is decomposable in natural condition and that it is safe one, because it is natural high molecule compound. Therefore, the said polymer is useful as a carrier.
In addition, it has been confirmed that the drug-containing polymer of the present invention represented as Polymer P2 also possesses capability of migrating into target organs and superior effect as shown hereinafter in Experiments.
BEST MODE FOR CARRYING OUT THE INVENTION
The following abbreviations in Experiments and Examples mean as follows:
PLGA: poly-L-glutamic acid,
HZ: hydrazine,
ED: ethylenediamine,
[ 3 H]PGE 1 -:
PGE 1 bonded to hydrazine or ethylenediamine wherein the said
PGE 1 is labeled with 3 H partially,
Gal: 1-thiogalactpyranosyl-2-imino-ethyl,
-HZ-Lac (reductive): a group of the formula
DMF: dimethylformamide,
MeOH: methanol,
MeONa: sodium methoxide,
EtOH: ethanol.
Experiment 1: Biodistribution of the Carrier Polymer of the Present Invention (Polymer P1)
PLGA-HZ-Gal (prepared in Example 3) and PLGA-HZ-Lac (prepared in Example 5) were labeled with 111 In and were injected into mouse through its tail vein at dose of 1 mg/kg to analyze biodistribution of them. The results are shown in Tables 1 and 2 (Each value in Tables means the percentage of concentration in 1 ml of plasma, the percentage of amount of accumulation in each organ and the percentage of urinary excretion of the said PLGA derivatives (mean±S.D.), respectively at various times after administration.).
TABLE 1
Biodistribution data of PLGA-HZ-Gal
1 min.
5 min.
10 min.
60 min.
Plasma
47.76 ± 4.87
11.86 ± 4.71
2.41 ± 0.29
0.98 ± 0.16
Kidney
3.38 ± 0.41
1.61 ± 0.47
0.75 ± 0.13
0.53 ± 0.17
Spleen
0.02 ± 0.05
0.20 ± 0.10
0.15 ± 0.04
0.08 ± 0.03
Liver
34.90 ± 0.12
64.80 ± 8.41
75.65 ± 3.12
67.40 ± 3.32
Lung
0.11 ± 0.03
0.12 ± 0.01
0.09 ± 0.01
0.06 ± 0.02
Urine
0.04 ± 0.06
3.06 ± 4.33
10.93 ± 1.14
15.30 ± 1.11
TABLE 2
Biodistribution data of PLGA-HZ-Lac (reductive)
1 min.
5 min.
10 min.
60 min.
Plasma
42.16 ± 0.56
17.11 ± 5.85
1.99 ± 2.10
0.06 ± 0.03
Kidney
4.49 ± 0.40
4.67 ± 1.15
2.30 ± 1.45
1.24 ± 0.15
Spleen
0.10 ± 0.01
0.21 ± 0.02
0.22 ± 0.07
0.19 ± 0.01
Liver
24.53 ± 4.35
44.16 ± 5.47
59.51 ± 4.56
56.47 ± 3.57
Lung
0.53 ± 0.10
0.36 ± 0.05
0.11 ± 0.05
0.03 ± 0.00
Urine
0.16 ± 0.13
5.46 ± 2.89
9.67 ± 3.00
0.91 ± 0.30
About 60% of PLGA-HZ-Gal which was administered was accumulated into liver at 10 min. after administration. The same level of accumulation of it was observed in liver at 60 min.
About 60% of PLGA-HZ-Lac which was administered was accumulated into liver at 10 min. after administration. The same level of accumulation of it was observed in liver at 60 min.
From the mentioned, it has proved that the carrier polymer of the present invention showed high level of accumulation and long-term accumulation of it in liver.
Experiment 2: Biodistribution of the Drug-containing Polymer of the Present Invention (Polymer P2)
Biodistribution of [ 3 H]PGE 1 -HZ-PLGA-HZ-Gal (prepared in Example 4, degree of polymerization=97) and [ 3 H]PGE 1 -ED-PLGA-ED-Gal (Comparison: the polymer described in International J. Pharmaceutics, 155, 65-74 (1997), degree of polymerization=101) was analyzed by the same procedure as described in Experiment 1. The results are shown in Tables 3 (Invention) and 4 (Comparison) (Each value in Tables means the percentage of concentration in 1 ml of plasma, the percentage of amount of accumulation in each organ and the percentage of urinary excretion of the said [ 3 H]PGE 1 derivatives (mean±S.D.), respectively at various times after administration.).
TABLE 3
Biodistribution data of [ 3 H]-PGE 1 -HZ-PLGA-HZ-Gal
1 min.
5 min.
10 min.
60 min.
Plasma
14.33 ± 0.75
1.64 ± 0.51
0.40 ± 0.06
0.26 ± 0.07
Kidney
1.26 ± 0.23
1.23 ± 0.06
0.79 ± 0.14
0.64 ± 0.22
Spleen
1.11 ± 0.14
1.85 ± 0.10
1.24 ± 0.17
1.84 ± 0.16
Liver
54.42 ± 0.79
70.39 ± 3.51
80.54 ± 9.52
85.43 ± 3.78
Lung
1.88 ± 0.46
1.64 ± 0.56
1.00 ± 0.21
0.44 ± 0.18
Urine
0.00 ± 0.00
1.17 ± 1.01
1.79 ± 0.25
1.45 ± 0.83
TABLE 4
Biodistribution data of [ 3 H]-PGE 1 -ED-PLGA-ED-Gal
1 min.
5 min.
10 min.
60 min.
Plasma
36.55 ± 1.63
6.33 ± 0.84
1.99 ± 0.42
0.00 ± 0.00
Kidney
9.58 ± 1.46
28.82 ± 2.82
33.25 ± 5.63
13.16 ± 1.32
Spleen
0.41 ± 0.06
0.37 ± 0.17
0.63 ± 0.27
1.02 ± 0.53
Liver
27.72 ± 3.81
41.16 ± 2.04
47.19 ± 1.03
45.12 ± 8.21
Lung
1.97 ± 0.85
1.40 ± 0.13
0.82 ± 0.33
0.69 ± 0.14
Urine
0.05 ± 0.05
3.77 ± 2.28
2.28 ± 1.61
6.56 ± 3.15
As shown in Table 3, 70% of drug which was administered was accumulated into liver at 5 min. after administration. In addition, 85% and 70% of drug were observed to be accumulated to liver at 1 hour and 24 hours after administration, respectively.
On the other hand, in Comparison (Table 4) group, 40% and 45% of drug which was administered were accumulated to liver at 5 min. and 1 hour after administration, respectively.
Therefore, it has proved that it is possible to deliver the drug at the higher concentration continuously into liver using the drug-containing polymer of the present invention.
Experiment 3: Effect of the Drug (PGE 1 )-containing Polymer of the Present Invention (Polymer P2) on CCl 4 Induced Liver Damage
A solution of 10% (v/v) of CCl 4 in sesame oil at dose of 10 ml/kg was administered into mouse abdominal cavity, and then drug (saline solution (Control), Free-PGE 1 (Comparison), drug (PGE 1 )-containing polymer of the present invention PGE 1 -HZ-PLGA-HZ-Lac (reductive) (prepared in Example 6)) were injected into mouse through its tail vein at the setting dose. After the mouse had been fasted for 18 hours (25° C., water was freely given), blood was collected to assay GPT level (IU/L) in plasma. The results are shown in Table 5.
TABLE 5
n
(No. of animals)
GPT level
Control (saline solution/CCl4 (−))
3
12.68 ± 1.527
Control (saline solution/CCl4 (+))
5
614.56 ± 250.3
Free PGE 1 (0.065 mg/kg)
5
660.89 ± 218.28
PGE 1 -HZ-PLGA-HZ-Lac
4
239.12 ± 77.482
(1 mg/kg)
As shown in Table 5, the drug (PGE 1 )-containing polymer of the present invention showed inhibition effect on increasing GPT level in plasma of CCl 4 induced liver damage significantly to compare with the group consisting of saline solution (Control group). In addition, the inhibition rate of increasing GPT level in the Invention group was three-time superior to that in the group consisting of free PGE 1 at the corresponding dose.
REFERENCE EXAMPLE AND EXAMPLES
The following Reference Examples and Examples are intended to illustrate, but not limit, the present invention. Each number represented as d t , x t , y t (t=1, 2, 3), z u (u=2, 3), w 3 in the column of degree of polymerization means mol of L-glutamic acid connecting COOR 1 (wherein, R 1 is C1˜6 alkyl, benzyl.), L-glutamic acid connecting COOH, L-glutamic acid connecting NH 2 , L-glutamic acid connecting G (galactose form or lactose form) and L-glutamic acid connecting D (PGE 1 ) per 1 mol of polymer.
Reference Example 1
Synthesis of PLGA-HZ (Degree of Polymerization: d 1 =0, x 1 =29, y 1 =50)
To γ-benzyl-poly-L-glutamic acid (MW: 17,300, degree of polymerization=79) (200 mg), solution of hydrazine.monohydrate (10 ml) in DMF (3 ml) was added at a dropwise with stirring. The mixture was reacted for 3 hours at room temperature. The reaction solution was dialyzed with dialysis tube (3,500 molecular weight cut-off) (When the inner solution of tube became to be gel, the solution was recovered to be homogenous condition by addition of an adequate quantity of conc. HCl.). Inner solution of tube was ultrafiltered (10,000 molecular weight cut-off), concentrated and freezed to dry to obtain the title compound having the following physical data.
It was confirmed that each benzyl group, which was a protecting group of glutamic acid, was removed entirely by NMR analysis. In addition, hydrazine residue was assayed by β-naphathoquinon-4-sulphonate method.
MW: 10,900; degree of polymerization: d 1 =0, x 1 =29, y 1 =50.
Example 1
Synthesis of PLGA-HZ-Gal (Degree of Polymerization: d 2 =0, x 2 =29, y 2 =8, z 2 =42)
(1) To cyanomethyl 1-thiogalacoside (150 mg), MeONa/MeOH (3 ml) was added. The mixture was stirred for 24 hours. MeOH was distilled off under reduced pressure from the mixture.
(2) PLGA-HZ (prepared in Reference Example 1) (50 mg) was dissolved in 2N HCl (1 ml). The mixture was neutralized by addition of 2N NaOH. Borate buffer solution (50 mM, pH9.5)(3 ml) was added thereto. The solution was added to the residue obtained in (1). The mixture was stirred for 5 hours at room temperature. The reaction solution was dialyzed, concentrated and freezed to dry to obtain the title compound having the following physical data. In addition, Gal residue was assayed by sulphate-anthron method.
MW: 20,900; degree of polymerization: d 2 =0, x 2 =29, y 2 =8, z 2 =42.
Example 2
Synthesis of [ 3 H]PGE 1 -HZ-PLGA-HZ-Gal (Degree of Polymerization: d 3 =0, x 3 =29, y 3 =7, z 3 =42, w 3 =1)
(1) PLGA-HZ-Gal (prepared in Example 1) (22.5 mg) was dissolved in 0.1M acetate buffer solution (pH5.0) (1 ml).
(2) To a solution of iced PGE 1 (2.5 mg) in EtOH (0° C., 1 ml), a solution of [ 3 H]PGE 1 (EtOH: H 2 O=7:3; 0.5 μCi/ml) (0.1 ml) was added.
(3) Stirring the solution prepared in the above (1) at room temperature, the solution obtained in the above (2) was added at a dropwise thereto. 0.1M acetate buffer solution (pH5.0) (0.5 ml) was added thereto to clarify the solution. The solution was stirred for 24 hours at 4° C. After removing the impurities from the reaction mixture, the solution was dialyzed. The dialyzed solution was ultrafiltered (10,000 molecular weight cut-off, concentrated and freezed to dry to obtain the title compound having the following physical data.
MW: 21,200; degree of polymerization: d 3 =0, x 3 =29, y 3 =7, z 3 =42, w 3 =1.
Example 3
Synthesis of PLGA-HZ-Gal (Degree of Polymerization: d 2 =0, x 2 =29, y 2 =37, z 2 =31)
By the same procedure as Reference Example 1→Example 1, the title compound having the following physical data was obtained using γ-benzyl-poly-L-glutamic acid (degree of polymerization=97).
MW: 20,800; degree of polymerization: d 2 =0, x 2 =29, y 2 =37, z 2 =31.
Example 4
Synthesis of PGE 1 -HZ-PLGA-HZ-Gal and [ 3 H]PGE 1 -HZ-PLGA-HZ-Gal (Degree of Polymerization: d 3 =0, x 3 =29, y 3 =32, z 3 =31, w 3 =5)
PLGA-HZ-Gal (prepared in Example 3) (20 mg) was dissolved in 0.01M acetate buffer solution (pH5.0) (5 ml). Stirring this solution, a solution of PGE 1 (4 mg) in EtOH (0.5 ml) was added at a dropwise thereto. The mixture was stirred over night at room temperature. The reaction solution was dialyzed by saline solution to obtain the title compound (PGE 1 -HZ-PLGA-HZ-Gal) having the following physical data. In addition, by the same procedure, the title compound ([ 3 H]PGE 1 ) having the following same physical data was obtained by addition of [ 3 H]PGE 1 (10 μCi) to the said solution of PGE 1 in EtOH. Both compounds were stored as a solution form.
MW: 23,000; degree of polymerization: d 3 =0, x 3 =29, y 3 =32, z 3 =31, w 3 =5.
Example 5
Synthesis of PLGA-HZ-Lac (Reductive/degree of Polymerization: d 2 =0, x 2 =35, y 2 =40, z 2 =22)
PLGA-HZ (MW: 13,300, degree of polymerization: d 1 =0, x 1 =35, y 1 =62) (50 mg) which was prepared by the same procedure as Reference Example 1 using γ-benzyl-poly-L-glutamic acid (degree of polymerization=97) was dissolved in 5N NaOH and neutralized to about pH7 by addition of 5N HCl. 0.1M borate buffer solution (pH8.5) was added thereto to become to pH8˜9. Lactose (143 mg) and sodium cyanoborohydride (50 mg) was added thereto. The solution was reacted for one day at 37° C. The reaction solution was purified with dialysis and freezed to dry to obtain the title compound having the following physical data.
MW: 20,800; degree of polymerization: d 2 =0, x 2 =35, y 2 =40, z 2 =22.
Example 6
Synthesis of PGE 1 -HZ-PLGA-HZ-Lac (Reductive/degree of Polymerization: d 3 =0, x 3 =35, y 3 =36, z 3 =22, w 3 =4)
By the same procedure as Example 2, the title compound having the following physical data was obtained using PLGA-HZ-Lac (reductive/prepared in Example 5).
MW: 22,800; degree of polymerization: d 3 =0, x 3 =35, y 3 =36, z 3 =22, w 3 =4. | Polymers derived from polymers represented by Formula (A) (d is 20˜500; and Rs, which may be the same or different, represent each H, alkyl or benzyl) by substituting a part or all of the consisting peptide bonds by (1) hydrazino-Glu (Formula B), and saccharide-modified Glu (Formula C) or by (2) hydorazino-Glu (Formula B), and saccharide-modified Glu (Formula C), and drug bonded Glu (Formula D). These polymers, which are carriers optionally bonded to drugs capable of migrating into target organs (cells), are useful as medicines | 2 |
TECHNICAL FIELD OF THE INVENTION
This invention relates in general to underground conduits, and more particularly to a gravel-packed pipeline.
BACKGROUND OF THE INVENTION
Underground conduits are widely used for the transmission of fluids and gases, such as in pipelines and the like, as well as for carrying wires and cables for the transmission of electrical power and electrical communications signals. While the installation of such conduits is time-consuming and costly for locations where the earth can be excavated from the surface, the routing of such conduits becomes more difficult where the surface excavation cannot be done due to the presence of surface obstacles through which the excavation cannot easily proceed. Such surface obstacles include highways and railroads where the installation of a crossing conduit would require the shutdown of traffic during the excavation and installation. Such surface obstacles also include rivers, which present extremely difficult problems for installing a crossing conduit due to their size and difficulty of excavation thereunder.
Prior methods for the installation of conduit have included the use of directional drilling for the formation of an enrouted underground arcuate path extending between two surface locations and under the surface obstacle with the conduit installed along the drilled path. A conventional and useful method for installing such underground conduits is disclosed in U.S. Pat. No. 4,679,637, issued Jul. 14, 1987, assigned to Cherrington Corporation, and U.S. Pat. No. 4,784,230, issued Nov. 15, 1988, assigned to Cherrington Corporation, both of which are incorporated by reference herein.
Several shortcomings of the prior methods are discussed in connection with U. S. application Ser. No. 557,992, filed Jul. 26, 1990, entitled "Improved Method and Apparatus for Enlarging an Underground Path", to Martin Cherrington and assigned to Cherrington Corporation, which is also incorporated by reference herein. A major concern in forming an underground conduit in a near horizontal position is the removal of cuttings resulting from the reaming operation. These cuttings may inhibit the pre-reaming and reaming operations and further inhibit the installation of the pipeline. It is believed that the cuttings, many of which are heavier than the fluid transporting them, will settle towards the bottom of the underground hole and then build up into a circumferential packed mass, especially when the rate of reaming is poor.
One application of horizontal conduits is for removing fluids and gases from a subterranean area. For example, a horizontal well could be drilled to reach an aquifer which would otherwise be unreachable because of a man-made or natural structure above the aquifer. Another application would be the removal of hazardous wastes which have leached into the soil, for example, from a oil tank above the subterranean area. A third application would be the infusion of gases or liquids into a subterranean area from a above-ground station.
In these applications, it is desirable to have a filtering medium, such as gravel, surrounding a slotted, or otherwise porous, pipe. Heretofore, centering a slotted pipe within a horizontal hole and surrounding the pipe with the filtering medium has been problematic. Prior art methods, such as filling the horizontal hole with a gravel and water mix and removing the water through the slotted pipe have proven ineffective in wells having a hole angle of approximately 45°-50° from the vertical. If the slotted pipe is not sufficiently surrounded with the filtering medium, materials from the horizontal hole will clog the slotted pipe and may foul the liquid or gas being removed. Furthermore, the cuttings remain in the hole, the filtering medium may become contaminated, thereby reducing its effectiveness.
Therefore, a need has arisen for a effective method and apparatus for installing a horizontal porous pipe surrounded by a filtering medium.
SUMMARY OF THE INVENTION
In one aspect of the present invention, a porous pipe is placed within a hole using a liner pipe for containing the porous pipe. The liner pipe is removed from the hole while maintaining the porous pipe in a desired position within the hole. A material conveyor pipe coupled to the liner pipe conveys the filtering material to the hole during removal of the liner pipe.
This aspect of the present invention provides the advantage that the filtering material is placed in the hole about the slotted pipe in a manner which thoroughly packs the hole with the filtering material.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:
FIG. 1 illustrates a cross-sectional diagram showing a gravel-packed porous pipeline used in an exemplary embodiment of toxic waste removal;
FIGS. 2a-b illustrate cross-sectional side and front views of apparatus for forming a gravel-packed porous pipeline after a first stage;
FIGS. 3a-b illustrate cross-sectional side and front views of the apparatus of FIGS. 2a-b after a second processing stage;
FIG. 4 is a side view of the preferred embodiment of hole cleaning device of the present invention;
FIGS. 5a-b are cross-sectional side and front views of the hole cleaning device of FIG. 3; and
FIGS. 6a-b are detailed cross-sectional views of the nozzle and throat assemblies.
DETAILED DESCRIPTION OF THE INVENTION
The preferred embodiment of the present invention and its advantages are best understood by referring to FIGS. 1-6 of the drawings, like numerals being used for like and corresponding parts of the various drawings.
FIG. 1 illustrates a cross-sectional view of a gravel-packed pipeline used in an exemplary embodiment to remove toxic waste. While the embodiment shown in FIG. 1 illustrates use of a gravel-packed pipeline for toxic waste removal, it should be noted that the gravel-packed pipeline may be useful in any environment where liquids or gases are to be extracted from or infused to a desired subterranean region.
In FIG. 1, a control subsystem 10 removes toxic waste (shown as a leak from oil tank 12) from a plume 14. The control subsystem 10 is coupled to a pipe 16 which is porous in the area of the plume 14. The porous pipe 16 is surrounded by a filtering material 18 which separates the porous pipe 16 from the walls of hole 20.
In the preferred embodiment, the porous pipe 16 comprises a slotted pipe, such as that sold under the trademark CIRCUMSLOT by Brainard-Kilman. Slotted pipes typically have slots of 0.010 or 0.020 inches, but other slot sizes may be appropriate depending upon the application. A slotted pipe is typically slotted around the entire circumference of the pipe to maximize flow through the pipe; however, in certain applications, another pipe structure may be appropriate.
In operation, the toxic waste from the plume 14 is drawn to the porous pipe 16 responsive to suction created by the control subsystem 10 or by a pump situated within pipe 16. The filtering material 18 (typically comprising gravel or sand) prevents material from the surrounding subterranean area, specifically from the walls of hole 20, from clogging the porous pipes 16. The toxic waste is then processed by the control subsystem 10 or removed offsite to another toxic waste control subsystem.
FIGS. 2a-b illustrates a cross-sectional side view of the apparatus used to place the porous pipe within the hole 20. The porous pipe 16 is placed within a liner pipe 22. A piston seal 24 creates an airtight seal between the end of the porous pipe 16 and an extended portion 26 of the liner pipe 22. A toggle anchor 28 is coupled to the seal 24 and slotted pipe 16, and is held in a contracted position within the extended portion 26 of the liner pipe 22. A conveyor pipe 30 is disposed above and coupled to the liner pipe 22. Stabilizers 32 are coupled to the bottom of the liner pipe 22 to maintain the liner pipe 22 substantially in the center of hole 20. Additional stabilizers 32 could be added for additional support or, in some instances, conveyor pipe 30 may act as a third stabilizer.
In the preferred embodiment, the stabilizer is typically manufactured from steel. The liner pipe 22 is typically a metal drill pipe, such as aluminum, and the conveyor pipe 30 is typically a steel pipe. The anchor 28 is manufactured from metal and is spring-loaded such that when the toggle anchor 28 is removed from the liner pipe 22, its anchor members 28a-b will extend outward to contact the walls of hole 20.
The piston seal 24 is typically a bunyl-rubber material. The liner pipe may be machined in the extended region 26 to provide extra smoothness.
The sizes of the respective liner and porous pipes 22 and 16 will vary depending upon application. The conveyor pipe 30 would typically have an outside diameter of approximately 13/4 inches in order to convey 3/16 inch gravel size.
In operation, the assembly shown in FIG. 2a is pushed into hole 20 from the surface. Formation of the hole 20 is discussed in greater detail below. The assembly of pipes is pushed into the hole 20 until the porous pipe 16 is substantially positioned within the plume 14.
Once positioned, the porous pipe 16 is removed from the liner pipe 22 as illustrated in connection with FIGS. 3a-b.
FIGS. 3a-b illustrate cross-sectional side and front views of the installation of the gravel-packed porous pipe after a second step. The piston seal 24 is pushed out of the liner pipe 22 by exerting air or water pressure within the liner pipe 22. This pressure may be provided from the surface using a mud pump or similar device. Once the toggle anchor 28 has cleared the liner pipe 22, the anchor members 28a-b are forced outward to the walls of the hole 20. The anchor members 28a and 28b have edges which dig into the holes of the wall 20 thereby locking the porous pipe 16 in place. Once the toggle anchor 28 is secure, the liner pipe 22 may be removed, typically by using a drilling machine. During removal, the stabilizers 32 maintain the liner pipe 22 in a desired position such that the porous pipe 16 is substantially centered.
As the liner pipe 22 is removed, the filtering material 18 is expelled from the conveyor pipe 30. The filtering material may be forced through the conveyor pipe 30 using a machine for mixing dry material and compressed air, such as the REED SOVA and SOVE GUNCRETE machines manufactured by Reed Manufacturing of Walnut, Calif. By forcing the filtering material 18 through the conveyor pipe 30 such that it is expelled at the end of the liner pipe 22 as it is withdrawn from the hole, the filtering material will completely fill the hole 20 without pockets of unfilled space which would allow material from the walls of the hole 20 to enter and obstruct the porous pipe 16.
The hole 20 may be formed in a variety of ways; however, the preferred method is to drill a pilot hole (for example, a two-inch hole) which is enlarged using a wash-over pipe (to about four inches). The wash-over pipe has a bit which opens the hole further (to about nine inches). The method is described in detail in U.S. Pat. No. 4,003,440, to Cherrington, which is incorporated by reference herein.
To facilitate insertion and removal of the liner pipe 22 and to remove debris which may contaminate the filtering material 18, it is desirable to remove the cuttings from the hole after hole formation.
FIG. 4 illustrates a cutaway view of a preferred embodiment of a hole cleaning device. In FIG. 4, the hole cleaning device 100 is shown in hole 20 having cuttings 102 remaining in hole 20. The exterior of the hole cleaning device 100 has a tapered front 106 to allow the hole cleaning device 100 to follow the contours of hole 20. Housing 108 has openings 110 to allow the cuttings 102 to pass from the hole 20 to the interior of the hole cleaning device 100.
In operation, the hole cleaning device 100 is rotated within hole 20 by a drilling motor on the surface. A pressure differential is created, as will be described in greater detail in connection with FIGS. 5 and 6, to draw the cuttings 102 through the openings 110. The cuttings 102 will be transported out of the hole 20 for processing by a solids control system (not shown).
FIGS. 5a-b illustrate a cross-sectional side view and a cross-sectional front view, respectively, of the hole cleaning device 100 which uses a jet pump to remove cuttings from the hole. A jet pump uses a stream of fluid (or gas) under controlled conditions to create a low-pressure area to which another material (in this case, cuttings) is drawn and subsequently combined with the fluid. Interior to the housing 108 is an outlet pipe 112. A cleaning substance, typically water or drilling fluid, is forced between the housing 108 and the outlet pipe 112. The fluid is fed through one or more inlet pipes 114 to a chamber 116. From the chamber 116, the fluid is forced through a jet nozzle assembly 118 into a diffuser assembly 120 which is in communication with the outlet pipe 112. The flow of the fluid through the nozzle assembly 118 and the diffuser assembly 120 causes a pressure differential by the Venturi effect. This pressure differential acts as a pump to draw the cuttings 102 through the openings 110 into the suction chamber 122 which is in communication with the diffuser assembly 120. The cuttings 102 in the chamber 122 are further drawn through the diffuser assembly 120 where they are mixed with the fluid and transported to the surface via outlet pipe 112.
FIG. 5b illustrates a cross-sectional front view showing the preferred embodiment of the hole cleaning device 100 of FIG. 4 wherein three inlet pipes 114 are used to transport the fluid from the area between the housing 108 and the outlet pipe 112 to the chamber 116.
In the preferred embodiment, the openings 110 are formed by providing holes through the exterior of the housing 108. During rotation of the housing, the holes will break large cuttings to a size which may be passed into the diffuser assembly 120. Thus, the size of the openings 110 should be determined based on the spacing between the jet nozzle assembly 118 and the diffuser assembly 120. In the illustrated embodiment, a 3/4 inch diameter hole has been found effective. Alternatively, a grate or other structure to size the cuttings could be implemented about the housing 108.
The space between nozzle assembly 118 and the diffuser assembly 120 is important to the operation of the hole cleaning device 100. An optimum length depends upon a number of factors including the composition of the subsurface through which the hole 20 is drilled, the speed of the fluid out of the jet nozzle, and the shape of the diffuser assembly 120. The illustrated embodiment shows an adjustable nozzle (illustrated in greater detail in FIG. 6b) which allow adjustments to provide the maximum cleaning action. The shape of diffuser assembly 120 also affects the efficiency of the hole cleaning operation.
FIG. 6a illustrates a detailed cross-sectional diagram of the nozzle assembly 118 and diffuser assembly 120. The jet nozzle assembly 118 includes an outer sleeve 124 into which an inner sleeve 126 is placed. A nozzle housing 128 is threaded into inner sleeve 126. Threads 130 allow the nozzle housing 128 to be extended or retracted into inner sleeve 126. Lock nut 132 holds the nozzle housing in place. Jet nozzle tip 134 is held by nozzle housing 128. The illustrated embodiment is best suited for experimentation to determine an optimum configuration for a particular application. After determining the optimum configuration, a fixed length jet nozzle would normally be used.
The diffuser assembly 120 includes outer sleeve 136 having diffuser 138 connected thereto. Outer sleeve 136 is coupled to outlet tube 112.
FIG. 6b is a detailed cross-sectional side view of the jet nozzle assembly 118. This view shows a more detailed view of the threads 130 between the nozzle housing 128 and the inner sleeve 126. Also shown are O-rings 140 for maintaining a seal between the assembly subcomponents.
While the present invention is illustrated in connection with the hole cleaner which operates to remove cuttings while being pulled towards surface, cuttings could also be removed as the hole cleaning device is pushed forward through the hole. Other devices for reaming and cleaning the hole are shown in U.S. patent application Nos. 789,356 and 790,223, entitled "Method and Apparatus for Cleaning a Bore Hole" and "Method and Apparatus for Cleaning A Bore Hole Using a Rotary Pump", both to Cherrington, filed contemporaneously herewith, and incorporated by reference herein.
Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims. | A gravel-packed pipeline is formed by inserting a liner pipe having a porous pipe contained therein. A conveyor pipe is attached to the liner pipe for conveying filtering material such as gravel. After positioning the liner pipe, the end of the porous pipe is pushed out and anchored. The liner is removed while the filtering material is conveyed to the hole. | 4 |
[0001] This is a continuation of PCT/HU99/00080.
DESCRIPTION
[0002] Subject of the invention is a flushing device for toilets containing a container with an air vessel, a connection piece for the network, a connecting pipe end for the valve, a connecting pipe end for the flush, a valve housing with a control device and jet tube. The jet tube is connected with the suction device.
[0003] Many devices for the flushing of toilets are known. The traditional flushing devices are in detail described in the book “Water supply, sewerage, gas supply” by Ballai-Marton (Technical Edition, Budapest 1977), page 593-599. Traditional flushing devices are equipped with an open water container with a volume of about 8 l, a water float and a weighted valve. When operated the whole quantity of water must run down from the container and for this reason these devices are economically disadvantageous. A braked, rapid stop cock is also known, which is directly joined in the network and flushes the pan from a height of about 700 mm. A disadvantage of this solution is that it requires a larger water branch (with a diameter of ¾-1″) and thus the effect of flushing mainly depends on the pressure in the water conduct.
[0004] Further on, in case of a pressure drop and a breakdown the sewage may be sucked back.
[0005] Closed containers with an air vessel at flushing also make use of the pressure in the water conduct. Such a solution is described in the patent documents HU 174,527, HU 190,422 and FR 2,122,069. The drawback of this solution is, that the air is continuously escaping from the pressure container. After a certain time the container loses its aircushion and operates as a valve being connected with the water network without a container. That means that compensation of the air cushion requires maintenance.
[0006] The U.S. Pat. No. 5,046,201 discloses a pressure container with a pressure control device where water feeds the injector, which is sucking air into the air vessel. The flush valve is provided with bars. The publication WO 98/39522 discloses a flushing system with a multiple valve under pressure. The U.S. Pat. No. 5,136,732 contains flushing devices with a piston and a needle valve. The patent document JP 6,158,699 discloses a pressure container with a vacuum valve. The patent document HU 205,409 describes a flushing device with an injector and a spring loaded and weight loaded external valve to introduce air. A common disadvantage of these solutions is, that they are relatively complicated, that the different valves and pressure controls are submitted to the forming of scale and choking, that means that they all need maintenances.
[0007] Purpose of the invention is the elimination of the existing disadvantages, development of a flushing device needing no maintenance and no introduction of air by the operator, which is silent, water saving and absolutely reliable in service.
[0008] Base of the idea being subject of the invention is the recognition that if the supply of air during the flushing process is solved through an opening without moving parts und if for the introduction of air the stream of the flushing water is deflected and stabilized, a more advantageous solution can be reached than up to now.
[0009] According to the purpose of the invention the device according to the invention is a flushing device for toilets comprising a container with an air vessel, a connecting pipe end for the network, a flushing pipe end, a valve housing provided with a control device and a jet tube, a suction device being connected with the jet tube in a way that on the housing of the valve beneath the control device an air refill opening is provided whereas above the control device—preferably inserted into the valve housing—an appropriate jet tube is arranged to deflect the flushing water, within the jet tube and/or beside it an air inlet chamber being left free.
[0010] Another characteristic of the invention may be that the suction device in the bottom part of the jet tube is provided at least with one inlet pipe end discharging into the container. The air inlet chamber is surrounded by a vault conducting the air to the air vessel.
[0011] In one embodiment of the invention the part of the jet pipe protruding into the valve housing contains a stabilizing chamber, which determines the direction of the water jet. The injector pipe, the suction device, the jet tube and the flushing pipe end are coaxial.
[0012] In another embodiment a complementary unit is built in between the suction device and the jet tube with a suction throat suitable to increase the yield of water. The complementary unit surrounds the integrating chamber.
[0013] The flushing device for toilets according to the invention has many advantages. It is extraordinarily simple and reliable in service, besides the control device by means of which the user starts and stops flushing it contains no moving parts. The device needs no maintenance and contains no parts subjected to scale or choking. Its functioning is noiseless and water saving. The user can stop flushing at any time. The introduction of air during the flushing process works automatically.
[0014] The application of an air refill opening has the advantage that a valve preventing back suction is not necessary. In case of a trouble the air refill opening cuts the suction effect and prevents the sewage from possible penetration into the water network.
[0015] In the following we present a more detailed description of the invention on the base of the enclosed drawings. The drawings present:
[0016] [0016]FIG. 1: Longitudinal section of the device
[0017] [0017]FIG. 2: Cross-section of the jet tube at 14 in FIG. 1.
[0018] [0018]FIG. 3: Cross-section of the jet tube over the suction device.
[0019] In FIG. 1 the container is shown in vertical position. At the top the connecting pipe end 2 for the network is arranged, the upper part of the container is being the air vessel 17 . The actual water level is marked by a triangle. The container 1 can be made of plastics, of metal or of a combination of both of them. It can be made of one or of more pieces. The injector tube 3 is arranged in the longitudinal axis of the container 1 and can be of a narrow shape or have a diameter according to FIG. 1. The suction device is in the lower part of the injector tube 3 and has two inlet pipe ends 12 discharging into the container 1 . The suction device 4 and the injector tube 3 are coaxial. In some cases the lower part of the injector tube 3 is choked.
[0020] The valve housing 6 is beneath the container 1 and preferably joins with the flushing pipe end 11 . In case of need the valve house is integrated with the container. The control device 10 can be a simple shut-off valve or a valve with remote control. Beneath the control device 10 the air refill opening 7 is arranged. Between the suction device 4 and the control device 10 the jet tube 15 is arranged which is suitable for the deflection of the flushing water. The jet tube 15 surrounds the stabilizing chamber 14 beside him the air flows in the air inlet chamber 5 . The air inlet chamber 5 is at the top surrounded by the guide vault 16 , which directs the air into the pressure vessel 17 . The jet tube 15 and the flush pipe end 11 are preferably coaxial. The complementary unit 8 is inserted between the injector pipe 3 and the jet tube 15 . The complementary unit 8 joins in the container 1 through the suction throat 13 suitable for increasing the water yield. The complementary unit 8 surrounds the collecting chamber 9 .
[0021] [0021]FIG. 2 shows the cross section of the jet tube 15 with the air inlet chamber 5 . FIG. 3 shows the cross section of the injector pipe 3 with the inlet pipe end 12 of the suction device 4 . Another embodiment is also possible in which the injector pipe 3 is connected with the jet tube 15 without the complementary unit 8 . The complementary unit serves for increasing the efficiency of the suction device 4 as a secondary element. The suction device 4 , the injector pipe 3 and the complementary unit 8 , applied according to need, are together named “water jet pump”. Within the framework of the claim hereafter specified the flushing device according to the present invention can also be made in other embodiments, e.g. the suction device 4 can also been arranged beneath the injector pipe 3 .
[0022] Functioning of the flushing device according to the invention:
[0023] In FIG. 1 the path of the water is marked by an arrow, the path of the air by a hatched arrow. The user opens the control device 10 . In the moment of opening the pressure in the air vessel 17 corresponds with the pressure in the water conduct. At the beginning of the flushing the water flows out of the container and the pressure in the air vessel 17 is gradually decreasing. As the pressure is falling the fresh water from the water conduct is flowing into the injector pipe 3 at a gradually increasing pressure. The water streaming into the injector pipe 3 exercises a sucking effect on the suction device 4 and the complementary unit 8 whereby the water in the container 1 through the inlet pipe end 12 and the suction throat 13 joins the main stream and mixes with it in the collecting chamber 9 .
[0024] The decrease of the quantity of water in the container originates a vacuum in the air vessel 17 . As a result of the pressure difference air is streaming into the air vessel 17 through the air refill opening 7 and the air inlet chamber 5 , which automatically compensates the air lost with the flushing water. The water in the container joining the water from the conduct under the effect of the injector in the stabilizing chamber 14 of the jet tube 15 assumes the cross section of the stabilizing chamber and while it flows through the control device 10 it nearly retains it. The rim of the water stream is marked by a dashed line. Owing to the shape of the jet tube 15 the water stream does not entirely fill up the cross section of the control device 10 and the valve housing 6 and thereby promotes the introduction of air in to the air vessel 17 .
[0025] After the flushing process is finished the control device 10 is being closed. Now the water from the network is filling the container 1 through the injector pipe 3 until the pressure in the air vessel 17 is equal to the pressure in the water conduct.
[0026] The flushing device according to the invention is used for water saving and reliable flushing of toilets. | The invention relates to a flush for toilets containing a container with an air vessel, a connection piece for the network, a connection piece for the flush, a valve housing comprising a control device and an injector tube. A suction device is joined to the injector tube. The flush is characterized in that an air-refilling opening ( 7 ) is arranged in the valve housing ( 6 ) underneath the control device ( 10 ) that is suitably accommodated in the valve housing ( 6 ). A jet tube ( 15 ) is arranged above the control device in order to deviate the flushing water. An air-introducing chamber ( 5 ) is arranged in and/or next to the jet tube ( 15 ). | 4 |
FIELD OF THE INVENTION
This invention relates to improvements in industrial process measurement apparatus capable of developing a signal that corresponds to the magnitude of a measurable physical parameter. More particularly, this invention relates to such apparatus employing resonant element sensors with fiber optic means to excite the resonant element and sense the resonant frequency.
BACKGROUND OF THE INVENTION
Instrumentation systems for use in measuring industrial process variables such as flow, pressure, temperature, and liquid level typically employ a sensing element located in a field location adjacent the process which responds directly to the process variable. The output signal of the sensing element is transmitted to a distant central station, e.g., a control room, for further signal conditioning and processing. In the majority of present industrial applications, an electrical measurement signal is produced at the sensor, and a two-wire transmission line provides the interconnection necessary to power the sensor and receive the measurement signal.
One class of measurement instrument for developing such a measurement signal that has been known for many years employs resonant elements as the primary sensing device. More recently an accurate, practical family of instruments of this general type has been devised and successfully marketed by The Foxboro Company as its 800-Series resonant wire sensors. While these devices represent a significant advance as evidenced by the high degree of commercial success which they have obtained, they do possess certain limitations, particularly when operating in severe, highly electrically noisy process environments.
Thus, room for improvement exists in the design and construction of industrial measurement instruments, especially in their accuracy while operating within troublesome process environments, by eliminating or minimizing undesired electrical effects.
SUMMARY OF THE INVENTION
The present invention provides a significant departure from those industrial measurement instruments of the past by providing an optical link between a resonant sensing element adjacent the process and a distant central station containing signal conditioning electronics. Energy necessary to activate the sensing element and induce mechanical vibration is thus supplied optically.
In a preferred embodiment to be described in detail below, a differential pressure measurement instrument of the resonant-wire type is linked to a control room by optical fiber means. One fiber transmits pulsed optical energy to activate the resonant-wire sensor, whose tension and hence resonant frequency varies in accordance with the pressure to be measured, while a second fiber sends an information-bearing signal back to the control room representative of the pressure measurement. The transmitted pulsed optical energy is photovoltaically converted into corresponding pulses of electric current which induce the wire, in the presence of a magnetic field, to vibrate at its resonant frequency. The other fiber senses oscillatory movement of the wire by reflecting transmitted steady-state light, which illuminates the moving wire, back into the fiber, thereby modulating the intensity of the steady-state light at a frequency that corresponds to the resonant frequency of the wire. To maintain the wire in resonance and thus minimize the amount of power required to drive the wire, a feedback network couples this composite reflected light signal to the supply of pulses to provide synchronization at the resonant frequency.
Alternatively, the fiber optic link between the process sensor and the control room may be achieved with a single fiber. This preferably involves the use of wavelength multiplexing onto the single fiber to provide the function of powering the resonant-wire sensor and detecting its frequency of vibration.
Other aspects and advantages of the present invention will become more evident after a review of the following detailed description taken in context with the accompanying drawings illustrating the principles of the invention.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram in block format of a field-located differential pressure measurement device communicating with signal processing elements within a control room constructed in accordance with a preferred embodiment of the invention; and
FIG. 2 is a schematic diagram showing the optical communications network employing a single fiber for transmitting power to and sensing the output of the pressure measurement device of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
As used throughout this written description and in the appended claims, the term "resonant element" is to be construed broadly. That is, it is intended to encompass not only vibrating wires or strings but also any characteristic structure that, when subjected to an external stimulus such as a pressure or force, will vibrate at a frequency which corresponds to the applied stimulus.
Turning now to FIG. 1, there is shown schematically a measuring instrument 10 employing a resonant element sensor 12 arranged to measure the magnitude of an unknown force (or pressure). The instrument is located in a process field 13 and is coupled by a pair of optical fibers 14, 15 to a central control room 16 having signal generating and processing equipment located therein. Although shown schematically as two distinct fiber optic cables, it will be appreciated that for typical process installations where the distance between field instruments and the control room is about one mile, these two fibers may be jacketed in a single cable with appropriate cladding to propagate the light.
The left-hand portion of FIG. 1 shows in block diagram format the mechanical components of the resonant element sensor 12, namely a wire 20 tautly positioned within the gap 21 of a magnetic assembly. This assembly consists of a permanent magnet and suitable pole pieces (collectively indicated by numeral 22) arranged to produce an intense magnetic field perpendicular to the longitudinal axis of the wire.
Although the operation of resonant element sensors is well understood by those of skill in the art, the following discussion represents a brief summary. The wire 20 is anchored at one end to a section of the instrument body indicated by numeral 24, while the other end is operatively coupled to a diaphragm 26 which alters the tension on the wire in response to an applied force. While the exact arrangement of components is not important for an understanding of the principles of the present invention, the pressure measuring instrument for this embodiment is that disclosed in U.S. Pat. No. 4,165,651, whose disclosure is hereby incorporated by reference. The wire is formed of electrically conductive material preferably with a polished reflective surface, and is electrically insulated from the instrument body by a bushing 23. When an alternating electric current is caused to flow through the wire, it is induced to vibrate at its resonant frequency which in turn is a function of the applied pressure. For purposes of illustration, it is assumed that the magnetic field is directed through the wire orthogonally to the plane of the drawing sheet, and thus the wire displacement follows the profile given by the dashed lines. A vibrating cycle is defined as a single excursion of the wire from its at rest or central null position to the left-most displacement back through the null position to its right-most displacement and back to the null position.
As shown the fiber 14 extends through a hole in the magnet assembly 22 to a position proximate the expected maximum deflection of the wire 20. This configuration permits the wire to be irradiated with light while a portion, depending on the instantaneous distance of the wire from the fiber, is reflected back into the fiber for transmission to the control room 16.
In operation, the electro-optical circuitry within the control room 16 provides the system drive energy through a regulated d-c power supply 30 that delivers a voltage input to a light emitting diode (LED) 32 and a feedback network 50 which in turn powers a second LED 33. The LED 32 provides, in conjuction with a pair of microlenses 34, 35 and a beam splitter 40, steady-state light into the fiber 14 for transmission to the wire 20. The use of microlenses at optical interfaces throughout the system to enhance optical energy transfer is well understood by those of skill in the art and such lenses are commercially available from Nippon Sheet Glass Company.
As mentioned, motion of the wire 20 results in a modulated light signal being reflected back to the control room 16 over the same optical fiber 14 where it is received at a photodiode 42 located at the return output 40A of the beam splitter 40. The electrical feedback network 50 coupled between the photodiode 42 and the LED 33 provides, through a microlens 36, light energy for the optical fiber 15 to activate motion of the wire 20. For this embodiment being described, a transformation of light energy into mechanical motion occurs at the field mounted end of the fiber 15 by a photodiode 62 whose electrical output is applied across the primary winding 64 of a transformer 66. The secondary winding 65 is directly connected to the wire 20.
It will be appreciated that this overall arrangement, although involving a mixture of electrical, mechanical and optical components, defines a closed loop oscillator. Moreover, as is well known by those of skill in the art, the system can be designed utilizing appropriate gain and phase shift selection to self-start from the electrical noise present or even from slight mechanical vibrations induced within the resonant-wire sensor 12 such that the loop will be at resonance within a few operating cycles.
Considering in more detail the operation of the system, and assuming that the wire 20 has begun vibrating, an a-c electrical signal will be developed at the photodiode 42 whose frequency is equal to that of the vibrating wire. This a-c signal is then applied to the feedback network 50. This network consists of a low-level a-c amplifier 52 to amplify the signal from the photodiode 42, a phase shift network 54 to compensate for phase differences within the closed loop to sustain oscillation, a pulse shaper 56, and a power amplifier 58. The output of the amplifier 58 becomes the drive voltage for the LED 33 which is thereby caused to emit a series of pulses of light. These light pulses, transmitted via the optical fiber 15 to the photodiode 62, produce (after suitable impedance matching by the transformer 66) corresponding current pulses through the wire that are precisely synchronized with the motion of the wire to produce maximum deflection (and hence a maximum amplitude resonant signal) with each successive pulse. Thus the output of the pulse shaper 56 represents the resonant frequency of vibration and hence the pressure measurement. This frequency signal may be read out directly at an output terminal 70 or alternatively supplied to a frequency to d-c converter 80 to produce a d-c control signal proportional to the pressure measurement.
In similar fashion changes to the resonant frequency of vibration caused by changes in pressure exerted on the diaphragm 26 are detected and automatically adjusted for within the closed loop to produce a new output signal representative of the change in the process parameters. The design details of an appropriate amplifier circuit described above are well within the knowledge of a skilled artisan.
In certain applications it may be desirous to provide a single optical fiber from communication between the process field and the control room. For these purposes, the arrangement of FIG. 2 (which focuses primarily on the optical energy transfer of the present invention) may be particularly advantageous. For simplicity, details of the electronic drive and feedback circuitry have been omitted, suffice it to say their operation will be similar to that already presented in detail above. Here a pair of LED sources 100, 200 of discernibly different wavelength (λ 1 , λ 2 ) are wavelength multiplexed at a dichroic beam splitter 300. The source 100 produces a pulse train of light at a frequency within the operative range (e.g., 1700-3000 Hz) of the resonant sensor 10 while the source 200 provides a steady-state beam of light. These two wavelengths are transported from the control room 16 over a single optical fiber 400 to a field-located dichroic beam splitter 500 which passes substantially all of λ 1 to the photodiode 62 for powering the sensor 10 while blocking λ 2 . In turn, effectively all of the steady-state light (λ.sub. 2) is reflected by the beam splitter 500 so as to illuminate the wire 20, with essentially none of λ 1 being directed along this path.
The return signal reflected from the wire 20 is as before the steady-state beam (λ 2 ) modulated in intensity by an alternating signal corresponding to the motion of the wire. This signal is then detected at a photodiode 600 and fed back through a suitable network 700 to close the loop with the LED source 100 thereby setting the pulse train frequency at the resonant frequency of the wire.
It may also be possible to utilize a single optical communication fiber to both power the sensor and detect its output without employing multiple sources and dichroic beam splitters. In such an arrangement, a pulsed beam of light is transmitted to the field and split in two paths, one to drive the wire, the other to illuminate the moving wire on a periodic basis. Although the waveforms of the reflected signal would be somewhat complicated due to the chopped nature of the incident light, the intensity of light reflected from the resonant wire would still be proportional to the distance between the wire and the adjacent optical fiber, with less light being reflected when the wire is furthest from the fiber and vice-versa. The returned illumination combined with the transmitted light produces a composite waveform representing the total illumination in a given instant of time within the optical fiber, i.e., a pulsed signal with a periodic alternating signal thereon. With suitable adjustments in the electronic design, a compatible oscillator could be built such that at resonance the transmitted light pulses would be synchronized with the motion of the wire. Such source synchronization is arrived at by the feedback arrangement previously discussed in detail above.
Thus numerous advantages of the present invention have been set forth in detail above. An instrumentation system employing a resonant element sensor has been demonstrated that operates by converting light energy into resonant physical motion, while transmitting measurement data in terms of frequency through optical sensing means. By eliminating electrical transmission between control room and field locations over copper wire conductors, problems associated with electromagnetic interferences as in past such systems have been alleviated. Installation of the present optical network within process plants may be simplified by eliminating the need for separate optical fiber conductors for powering and sensing by effectively providing two-way communication over a single optical fiber. Additionally, the feedback technique of the present invention besides sustaining oscillations also allows the largest amplitude of vibration for the lowest possible power input. This arrangement thus is particularly suitable to permit the use of low power LED sources for communicating over the distances involved while still maintaining an effective signal to noise ratio.
Although a preferred embodiment of the invention has been described in detail above, this is solely for the purpose of illustration and is not intended to be limiting. Numerous modifications will become apparent to those of skill in the art. For example, the invention has been described throughout as operating with resonant element sensors that are activated by electro-magnetic energy and hence a conversion from light energy to electrical energy has been shown. It will be understood that other techniques could be devised for applying the supplied light energy to the sensor element to effect resonant physical motion without departing from the scope of the invention as defined in the accompanying claims. | An instrumentation system for use in measuring and processing industrial process variables, such as flow, pressure, or temperature, includes a resonant element sensor whose resonant frequency varies in accordance with changes in the desired process variable communicating through an optical fiber link to a distant control room. The sensor is activated into resonant physical motion by light energy from a source in the control room, while the motion of the wire is sensed optically and retransmitted to the control room to produce an output signal whose frequency is equal to that of the resonating element. A feedback network maintains the sensor in resonance by synchronizing the delivery of light energy to the motion of the resonant element. The powering and sensing aspect may be performed by individual fiber optic cables or alternatively this function may be combined by utilizing a single fiber optic strand. | 6 |
FIELD OF THE INVENTION
[0001] The present invention relates to an irrigation control system, and, more particularly, to a system and method for managing water and other substances in plant root zones.
BACKGROUND OF THE INVENTION
[0002] Irrigation has been practiced for thousands of years and not much has changed in how it is practiced. Irrigation had been limited to water movement by gravity, animal and human power, and then later windmills and steam engines were employed to move water as those technologies developed. The development of the internal combustion engine enabled by the use of steel and large dams having been enabled by the use of concrete has provided the reservoirs and the devices to move stored water great distances to be applied to fields. These technologies also enabled deep wells and pumps to draw water up from the depths of aquifers such as the Ogallala aquifer in the south central United States. Steel pipes carry the water to the ends of the fields for furrow irrigation or above the fields for pivot irrigation. These technologies have been in place since the 1960's. Water movement under human control was supplemented by automatic control in the 1970's and 1980's which is further enabled by developments in microprocessors and sensors which can provide a signal that a measured amount of water has been delivered to a certain point in the field or that a certain amount of water had been applied to the field.
[0003] Water control has evolved into field water management in the 1990's and early 2000's. Point monitoring and control of water became distributed control thanks to the development of wired and wireless networks and global positioning systems (GPS). Field data collection, weather data collection and site specific irrigation control could be performed at different locations.
[0004] What is needed in the art is a new and cost efficient method and apparatus for managing water.
SUMMARY OF THE INVENTION
[0005] The present invention provides a fluid distribution control system that is dependent upon the need of a plant, based on a three-dimensional estimate of needs and for estimating those needs at a future time period.
[0006] The invention comprises, in one form thereof, a method for managing substances in a plant root zone, including the steps of providing a fluid distribution system, controlling the fluid distribution system, modeling the plant root zone, and distributing the substances thereto. The fluid distribution system is associated with an agricultural area. The fluid distribution system is controlled by way of a controller. The plant root zone is modeled for a plurality of locations in the agricultural area. The modeling step incorporates a desired three-dimensional distribution of the substances for each of the plurality of locations for a future time period. Substances are distributed to the plurality of locations by way of the fluid distribution system under control of the controller. The controller is dependent upon the desired three-dimensional distribution and the future time.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a representative irrigation system illustrated in a perspective view thereof utilizing an embodiment of the control method and apparatus of the present invention;
[0008] FIG. 2 illustrates an agricultural area having zones in which the irrigation system of FIG. 1 is utilized; and
[0009] FIG. 3 is a schematic illustration of an embodiment of components of the system and informational inputs used by an embodiment of the method of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0010] Referring now to the drawings, and more particularly to FIGS. 1-3 there is illustrated an irrigation system 10 having a movement system 12 and a distribution system 14 including pipes 16 and nozzles 18 . Although irrigation system 10 is illustrated as a pivot type of system other types of irrigation systems are also contemplated including, for example, drip tape irrigation as well as any other type. Irrigation system 10 moves across agricultural area 20 by way of movement system 12 . Distribution system 14 has water and other substance delivered through pipes 16 and out nozzles 18 under the control of a controller system 50 . As irrigation system 10 moves across various sub-areas 22 and crosses boundaries 24 different portions of irrigation system 10 are activated by activating individual nozzles 18 to respond to the three dimensional needs of the crops growing in agricultural area 20 in the different sub-areas 22 as irrigation system 10 moves in agricultural area 20 . As a nozzle 18 crosses a boundary 24 , control system 50 alters the output of that nozzle 18 to correspond to the particular need in the plant root zones of the particular sub-area.
[0011] Although sub-areas 22 have been shown having boundaries 24 , the representation shown in FIG. 2 is for the ease of illustration and it is to be understood that the location of boundaries 24 may be separately established for both soil model 68 as well as crop model 72 . For example, one sub-area may be used for soil model 68 that corresponds to a particular soil makeup, and a different sub-area shape may be used for crop model 72 that is based on genetic and performance information 74 for the crop. Moisture sensors 64 , which may be located at some of the nodes, represented by the ‘+’ symbol in FIG. 2 , may also contribute to the definition of boundaries 24 for either crop model 72 or soil model 68 since the models are effected by the three dimensional moisture distribution. Sub-areas 22 are fluid in that they are established based on inputs received by controller 52 and result in the selection of the amount of water 58 , the amount of substances 60 , the duration and flow rate delivered to a particular sub-area 22 by irrigation system 10 .
[0012] Control system 50 includes a controller 52 , a user interface 54 and a valve system 56 that receives water from water source 58 and other substances 60 that are then sent by way of valve system 56 to distribution system 14 . Substances 60 may include nutrients, herbicides, pesticides, fungicides, nematicides, salt, minerals, dyes or other fluid borne or dissolved elements or compounds. Controller 52 receives inputs from moisture sensors 64 , evapotranspiration data 66 , soil model 68 , crop model 72 , human observations 76 , remote sensed data 78 , business rules 80 and business information 82 . Soil model 68 receives input from weather data 70 and crop model 72 receives input from genetic and performance information 74 for the particular crops being grown in agricultural area 20 .
[0013] Even though different crops or crops with different genetic traits may be in agricultural area 20 , for ease of understanding, agricultural area 20 will be assumed to be growing a singular crop across all sub-areas 22 . Sub-areas 22 representing different two-dimensional locations within agricultural area 20 . Three dimensional information and models for the different locations in agricultural area 20 provide insight into the needs of the plants in their root zones, which is utilized by controller 52 for the distribution of resources 58 and 60 to meet a need for a future time period.
[0014] The present invention controls the movement of water from water source 58 and other substances 60 through distribution system 14 with a focus on optimizing desired conditions for individual plant root zones in terms of the three-dimensional distribution of water, nutrients and other substances, such as salt. The present invention considers plant genetics, the natural environment and management options with varying outcomes and risks. It utilizes technical advances in computational hardware, crop, weather and soil modeling, water marketing, business risk assessments and global food chain management. The system and method manages substances in the plant root zones that are based upon soil models 68 for separate sub-areas 22 . Soil model 68 includes a ‘Z-direction’ model with predicted future needs at different depths for X-Y locations of the two dimensional view of FIG. 2 . Soil model 68 is correlated with crop model 72 to determine the needs of the particular crop in terms of the depth below the surface of the ground for substances 60 as well as for water 58 .
[0015] Controller 52 may be a single computer, a computer with multiple processors, or a distributed processing system that is spatially distributed and networked together to work on the common task of the present method. Controller 52 can send an actuating signal to a valve system 56 that may include a number of valves controlling the flow through pipes 16 to separate individual nozzles 18 of irrigation system 10 . Valve system 56 may provide a feedback signal to controller 52 to indicate the position of the valve and/or other information such as the instant or accumulative flow through the valve.
[0016] Most prior art irrigation systems have one valve for the entire area being irrigated or a number of valves, each regulating water flow for a portion of the total irrigated area. If there are multiple valves, each one may be controlled individually. Management of a prior art irrigation system is done based on sensed soil moisture from soil moisture sensors, which is compared to a target value by a processor. The difference is used to determine the position of the valve for control purposes. An alternate approaches uses evapotranspiration data to estimate a water deficit. The valve is then controlled to apply water to make up this deficit. Both of these methods suffer from the same deficiencies. One is that due to sensor cost, the spatial resolution of the control inputs, such as soil moisture or evapotranspiration, is typically poor and leads to some areas being under watered and some areas being over watered. Another weakness in the prior art is that such systems are often reactive. They take current and past data into account and maybe a short term weather forecast and then react to it. A third short fall of the prior art methods is that they do not utilize remotely sensed data such as images that indicate crop coverage of soil, crop growth stage, crop biomass, crop leaf area and crop stress due to moisture or nutrient distribution. A fourth short coming is that they do not easily incorporate ground truthing from human observations. A fifth short coming is that they are not integrated with business rules and business information, which should affect application amounts due to the cost of water and the value of the water applied to the crop. If a map is used as in some prior art systems a target volume of water or nutrient is applied to each management area. The processor in such a system uses positional information to locate a given valve and then control is undertaken so that the volume of water or nutrient is applied to that area. The present invention differs from the prior art in that the valve is controlled in a way to achieve a distribution of water, nutrients and other substances, such as salt around the plant root zone, which is a three-dimensional location at a future point in time. In the present invention the use of soil models, such as SIS, crop models, weather data, business rules, business information and even remote sensed data are utilized.
[0017] Soil model 68 and crop model 72 are supplied with other data, which can include evapotranspiration data that enables a high spatial and temporal resolution estimate of current crop water needs. This estimate is three-dimensional in the root zone and includes water availability by depth and also considers soil moisture variability arising from factors within the model including, but not limited to, soil structure, crop growth stage and business rules 80 to implement techniques such as root deficit irrigation (RDI) in which crops are intentionally water stressed for a benefit at a later crop growth stage. The soil model 68 and crop model 72 may be ground truthed by entry of human observations 76 of crop or soil conditions. Controller 52 may also use soil moisture sensors 64 for ground truthing soil model 68 and evapotranspiration data 66 to calculate the amount of water entering the atmosphere from sub-areas 22 .
[0018] Business rules 80 and business information 82 enable water amounts to be adjusted based on crop value of incremental additions or subtractions of the recommended amounts of water 58 and substances 60 . Crop model 72 and soil model 68 run with different irrigation water amounts and application rates such as, for example, 1 inch-acre/hour for two hours versus 2 inch-acre/hour for one hour. The crop value at harvest for a given quality of the crop is part of the business information 82 . The crop value may be a single value, a function of maturity date or a complex probability distribution of value based upon crop and demand forecasts for the produced crop around the world. Models 68 and 72 are utilized along with rules 80 and information 82 to adjust water amounts so that the risk to the crop is reduced by applying more water at an earlier time to reduce a likelihood of a shortage at a critical crop growth phase in the future. Business rules 80 are also utilized by controller 52 to adjust water amounts based on alternate uses of water source 58 and/or substances 60 such as when the heat is so extreme that irrigation system 10 cannot keep up with losses and/or water source 58 and/or substances 60 may have more value being sold to other users in a market system than being consumed by irrigation system 10 .
[0019] User interface 54 displays a variety of audio and visual forms and may include voice synthesis delivered to a user at a remote location to a phone or various electronic displays so that information may be reported to the user by way of user interface 54 . User interface 54 may include an irrigation “dashboard” providing a summary of irrigation system 10 and the status of agricultural area 20 . Information may also be received relative to unauthorized movement of sensors 64 or even the condition of sensors 64 and other elements of mechanisms contained in irrigation system 10 . System 50 provides estimated past, present or future states of soil moisture in agricultural area 20 at various sub-areas 22 . User interface 54 allows the user to override the recommendations of controller 52 or authorize those recommendations. User interface 54 includes authentication software to ensure that only authorized users make changes to system 50 .
[0020] Advantageously the present invention provides for the computation of a three-dimensional soil model of the need for nutrients and/or water at various depths in sub-area portions of agricultural area 20 . Crop model 72 incorporates genetic and performance information 74 to better define the needs of the crop including such things as salt tolerance and moisture needs at various stages of maturity of the crop. Various inputs to controller 52 provide for cross checking of information, such as remotely sensed data 78 , the ground truthing by human observation 76 and/or localized moisture sensors 64 to provide levels of assurance that future needs of the plants will be properly met in the root zones of various sub-areas 22 . Soil model 68 models soil types in various sub-areas 22 or even further divided areas within agricultural area 20 . Soil model 68 incorporates the reactions of soil to current moisture and substances 60 , rates of distribution within the soil and the need for the variable rates of distribution by distribution system 14 to the crops in order to achieve the future transportation of substances 60 with water source 58 to a proper root zone level of a particular sub-area 22 . Advantageously, business rules 80 and 82 incorporate market information for the inputs into irrigation system 10 as well as the marketing value of the crop that is to be output from agricultural area 20 in order to optimize a return on investment or to reduce risk based upon future needs of the crop in agricultural area 20 as well as costs of substances 60 and water 58 .
[0021] Having described the preferred embodiment, it will become apparent that various modifications can be made without departing from the scope of the invention as defined in the accompanying claims. | A method for managing substances in a plant root zone, including the steps of providing a fluid distribution system, controlling the fluid distribution system, modeling the plant root zone, and distributing the substances thereto. The fluid distribution system is associated with an agricultural area. The fluid distribution system is controlled by way of a controller. The plant root zone is modeled for a plurality of locations in the agricultural area. The modeling step incorporates a desired three-dimensional distribution of the substances for each of the plurality of locations for a future time period. Substances are distributed to the plurality of locations by way of the fluid distribution system under control of the controller. The controller is dependent upon the desired three-dimensional distribution and the future time. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is related to the field of integrated circuits and surface mount technology (SMT). More specifically, the present invention is directed to an improved solder paste brick design for reducing voiding caused by volatized flux gases trapped within solder joints formed between ball grid array (BGA) integrated circuit (IC) devices and printed circuit boards (PCBs), chip carriers, or other similar components, during reflow soldering processes.
2. Description of Related Technology
Surface mount technology (SMT) is increasingly being employed as a cost-effective means of mounting IC devices to printed circuit boards. Numerous different techniques for mounting integrated circuit devices to circuit boards, chip carriers, or other components fall within the general category of SMT. Of these techniques, area array (as opposed to perimeter array) technology is often used to mount high I/O density packages with a great degree of reliability and manufacturing efficiency. Area array techniques include the use of pin grid arrays (PGAs), column grid arrays (CGAs), and ball grid arrays (BGAs). The more recent BGA and CGA techniques provide substantial improvements over PGA methods in that higher densities, reliability, and efficiency can be obtained for many types of packages.
Common BGA package configurations include ceramic (CBGA) and plastic (PBGA), as well as micro-BGA (MBGA). Each of these types of packages has its own attributes, which are also well understood in the field of SMT. Package outline specifications are presented in industry standards such as the joint industry council (JEDEC) publication 1995. In addition to individual IC devices, multi-chip modules or chip carriers can also be effectively surface mounted using area array techniques.
As the name implies, ball grid arrays (BGAs) utilize a grid or array of electrical terminals, such as solder bumps or balls arranged on one side of the IC package to effectuate electrical contact with the circuit board. The solder bumps of the array may vary in material, size (height and width) and pitch (i.e., bump-to-bump spacing) based on the individual package. Standard bump heights may range from less than one to several millimeters. Standard pitches in common use are 1.00, 1.27, and 1.50 mm (PBGA) and (CBGA) and 0.5 mm (MBGA). Additionally, the solder bumps may be arranged in a uniform or non-uniform array pattern, with some leads removed in certain areas, which is referred to as “depopulation,” depending on the desired attributes of the package.
Solder bumps or balls are typically attached to the pads of a PCB using a eutectic solder paste which holds the BGA device onto the PCB during the reflow process. The solder paste typically consists of a thick viscous fluid-like substance, called flux, which is mixed with tiny solder particles, or “spheres”, to form the paste. Solder paste “bricks” are formed from the eutectic solder paste and positioned within the perimeter of each pad in order to make contact with the solder ball terminals of the BGA device. The flux, within each solder paste brick has a consistency and “tackiness” similar to that of honey and sticks to the solder ball terminals with which it comes into contact.
After the BGA device is attached to the PCB as described above, the BGA device is mounted to the PCB using reflow solder processing techniques. Reflow solder processes generally use forced convection heating (air or nitrogen) to melt and reflow solder balls and/or paste interposed between the surfaces to be joined. The BGA device and PCB assembly is then exposed to a temperature profile which results in reflow of the solder. Surface tension created in the resulting solder liquid mass during reflow tends to prevent collapse of the solder, causing the joint to eventually solidify in a barrel or truncated sphere shape that is commonly referred to as a Controlled Collapse Chip Connection, or “C-4”. Numerous variations on this general theme exist, including the use of two more different solders with various melting points to produce reflow of various portions of the joint during different processes, or to allow rework.
Attachment of a PBGA device, for example, onto a PCB is typically accomplished by using solder paste bricks which are formed by screen printing eutectic solder paste onto an array of solder pads on the PCB. A typical method of screen printing includes the step of placing a solder paste stencil, having apertures that are of the same shape as the desired solder paste bricks, onto a PCB such that the apertures are aligned with the pads of the PCB. Solder paste is then applied to the unmasked areas, and the stencil is subsequently removed. The PBGA device is then placed on the PCB such that the solder ball leads contact the solder paste bricks on the etched pads. The entire assembly is then passed through a reflow process which applies a predetermined time/temperature profile to the solder paste bricks to liquify the solder paste bricks and the solder balls of the PBGA device, thereby forming solder joints between the BGA device and the pads of the PCB. The fully reflowing solder joints, coupled with the relatively large solder joint pitch (compared to leaded devices) allow the package to self-align during reflow through the equalization of surface tension forces, as described above. The self-alignment feature of the PBGA is largely responsible for the high assembly yields observed with this package in production.
FIG. 1 depicts a typical prior art surface mount of a BGA IC device 101 having solder ball terminals 103 aligned on top of solder paste bricks 105 which are positioned on top of contact pads 107 of a printed circuit board 109 . FIG. 2 is a side view taken along lines 2 — 2 of FIG. 1, of the BGA IC device 101 positioned on top of the PCB 109 such that the solder ball terminals 103 are aligned on top of corresponding solder paste bricks 105 , which are deposited on top of etched pads (not shown) of the PCB 109 .
One of the main disadvantages of the BGA technology from a manufacturing perspective is that the solder joints are hidden under the package instead of being visible along the device perimeter. Another disadvantage is that individual lead touch-up is not possible; the entire device must be removed and reworked if even a single connection is faulty. In addition, the equipment and overhead required to inspect and rework a faulty BGA component is expensive and time-consuming. The penalty to a manufacturer who creates a faulty BGA solder joint is very high; therefore, it is desirable to create an assembly process that has the best chance of avoiding defects.
The formation of solder paste bricks by solder paste screening is one of the most important steps in BGA assembly, and effective control of the paste deposit is a key to high yield manufacturing of BGAs. BGA components depend on solder paste bricks for providing either flux or a combination of flux and solder for attachment of the component to the PCB. However, a serious problem associated with soldering BGA devices onto a PCB with the use of solder paste bricks, is that volatized flux gases are often trapped within the resulting solder joint, causing voiding in the solder joint.
As part of the reflow cycle, the solder paste bricks go through a soaking temperature zone, in which the flux begins to boil and evaporate, but the solder balls of the BGA device and the solder spheres of the solder paste do not melt. It is during this soaking temperature zone that flux gases can migrate out of the solder joint and thus not cause voids. However, all of the volatized flux gases formed during the soaking temperature phase often do not escape the solder paste brick before the solder balls of the BGA and the solder spheres of the solder paste bricks begin to melt and reflow, at which point the volatized flux gases may become trapped in the melted solder joint formed by the solder balls and the solder paste bricks. As the solder joint cools and hardens, these volatized flux gases become permanent voids within the solder joint which can affect the mechanical properties of the joint and deteriorate the strength and the fatigue life of the joint. Voids can also produce spot overheating, hence reducing the reliability of joints. FIG. 3 is a cross-sectional view of a solder joint 111 formed between BGA device 101 and a pad 107 of a PCB 109 . A void 113 caused by entrapped flux gasses, as discussed above, is shown within the solder joint 111 .
The emergence of BGA technology has addressed the need for higher circuitry density and has also provided a more efficient way to solder IC's onto a PCB. However, frequent occurrences of large voids in the BGA assembly pose a great concern about the reliability of soldered joints formed under a BGA device. The presence of voids, as discussed above, cause problems in joint reliability and performance.
In view of the foregoing problems associated with BGA devices in SMT applications, what is needed is an improved method and/or apparatus which reduces the amount of voiding in the solder joints formed during the reflow process.
SUMMARY OF THE INVENTION
The present invention addresses the above and other needs by providing an improved solder paste brick design that reduces the distance volatized flux gases must travel to escape from the volume of the solder paste brick. The improved solder paste brick also performs the function of holding a BGA device in place on a PCB such that the solder balls of the BGA device are in proper alignment with designated pads on the PCB during reflow soldering of the BGA device onto the PCB. Therefore, the improved solder paste brick design significantly reduces the number and size of voids which may be formed in a solder joint, while not sacrificing the desirable property of holding BGA parts in proper alignment with the PCB before and during the reflow process. The BGA device is held in place because of the tackiness of the flux associated with the solder paste brick, which “sticks” to the solder balls that touch it.
In one embodiment of the invention, a method of soldering a ball grid array device onto a circuit board includes: positioning a solder paste brick on top of a pad of the circuit board, said solder paste brick defining an irregularly shaped structure so as to facilitate the escape of volatized flux gases from within the solder paste brick during a reflow soldering process; attaching the ball grid array device onto the circuit board such that a solder ball terminal of the ball grid array device makes contact with the solder paste brick and is substantially aligned on top of the pad; and heating the ball grid array device and the circuit board so as to melt the solder ball terminal and the solder paste brick, thereby forming a solder joint between the ball grid array device and the circuit board.
In another embodiment, a method of soldering a ball grid array device onto a circuit board includes: positioning a solder paste brick on top of a contact pad of the circuit board, said solder past brick defining an irregularly shaped structure such that a majority of a top surface of the solder paste brick is not in contact with the solder ball terminal, wherein volatized flux gases formed during heating escape via the top surface without migrating upwardly into the solder ball terminal; attaching the ball grid array device onto the circuit board such that a solder ball terminal of the ball grid array device makes contact with a portion of an edge of the solder paste brick while remaining substantially aligned with a center of the pad; and heating the ball grid array device and the circuit board so as to melt the solder ball terminal and the solder paste brick, thereby forming a solder joint between the ball grid array device and the circuit board.
In a further embodiment, a method of soldering a ball grid array device onto a circuit board includes: positioning a plurality of solder paste bricks on top of a plurality of contact pads of the circuit board, each solder paste brick defining an irregularly shaped structure such that a majority of a top surface of each solder paste brick is not in contact with a respective solder ball terminal so that volatized flux gases formed during heating escape via the top surface of each brick without migrating upwardly into the solder ball terminals during heating, wherein each brick is positioned on top of a respective pad, and wherein each brick is oriented such that it is rotated a specified number of degrees with respect to a brick located on top of an adjacent pad; attaching the ball grid array device onto the circuit board such that each solder ball terminal of the ball grid array device makes contact with a portion of an edge of a respective brick while remaining substantially aligned with a center portion of a respective pad; and heating the ball grid array device and the circuit board so as to melt each solder ball terminal and each solder paste brick, thereby forming solder joints between the ball grid array device and the circuit board.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a BGA device having solder balls in contact with solder paste bricks which are positioned within pads of a PCB, in accordance with the prior art.
FIG. 2 is a side view of a BGA device, taken along line 2 — 2 of FIG. 1, the BGA device having solder balls in contact with solder paste bricks positioned within pads of a PCB, in accordance with the prior art.
FIG. 3 is a magnified side view of a solder joint, having a void therein, formed by a reflow process in accordance with prior art use of solder paste bricks.
FIG. 4A is a perspective view of one embodiment of a prior art solder paste brick design.
FIG. 4B is a perspective view of another embodiment of a prior art solder paste brick design.
FIG. 5 is a perspective view of one embodiment of a solder paste brick design in accordance with the present invention.
FIGS. 6A-6C are top plan views of the solder paste brick designs of FIGS. 4A-4B and 5 , showing respective contact areas where a solder ball of a BGA device makes contact with the respective solder paste brick.
FIG. 7 is a top view illustrating one embodiment of an arrangement of solder paste bricks within pads of a PCB in accordance with the invention.
FIGS. 8A-8C are top views of various solder paste brick shapes illustrating the relative distances, represented by arrows, that flux gases must travel in order to escape the volume of different types of solder paste bricks.
FIG. 9A is a perspective view of another embodiment of a solder paste brick design in accordance with the invention.
FIG. 9B is a perspective view of another embodiment of a solder paste brick design in accordance with the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The invention is described below with reference to the Figures wherein like numerals refer to like elements throughout.
Referring again to FIG. 1, a typical surface mount of a BGA device 101 onto a PCB 109 , is shown. As depicted in FIG. 1, the BGA component 101 has solder ball terminals 103 arranged in an array pattern on a bottom surface of the BGA component 101 . The solder ball terminals 103 serve as leads of the BGA component 101 and make contact with solder paste bricks 105 which are positioned atop electrical connection pads 107 of the PCB 109 . The BGA IC device 101 is placed on top of the PCB 109 such that the solder ball terminals 103 are aligned with the solder paste bricks 105 . During reflow processing, the solder ball terminals 103 and the paste solder elements melt and form electrical contacts between the BGA device 101 and the pads 107 of the PCB 109 .
As previously described, the solder paste bricks 105 are typically comprised of a mixture of flux and tiny solder particles, or spheres, which give the bricks 105 a paste-like consistency. In one embodiment, the material for the solder ball terminals, as well as the solder spheres of the solder paste is a metal eutectic which includes the following compositions: 63% Sn/37% Pb, 62% Sn/36% Pb/2% Ag, and 62% Sn/36% Pb/2% In, all with a melting point of roughly 180° C. It should be appreciated, however, that other solder compositions with different melting points may be used in accordance with the present invention.
During the reflow process, the PCB 109 , along with the attached BGA component 101 , is subjected to an initial “soaking temperature,” typically in the range of 130°-150° C., for a period of approximately 40-90 seconds. After the PCB/BGA device assembly has undergone the soaking temperature phase of the process, the assembly enters into the reflow phase in which it is heated to a temperature range of 180°-200° C. During this phase, the solder ball terminals 103 as well as the tiny solder spheres of the solder paste bricks will begin to melt and liquify.
It is during the soaking temperature phase that the flux within the solder paste bricks begins to boil and evaporate forming volatile flux gases. These flux gases can migrate out of the solder paste brick 105 during the soaking temperature phase. However, often with the use of prior art solder paste brick designs, all of the volatized flux gases do not escape from the solder paste brick 105 before the PCB/BGA assembly enters the reflow phase and the solder spheres of the brick 105 and the solder ball terminals 103 begin to melt to form solder joints. These flux gases may become trapped within the solder joints formed as the solder ball terminals 103 and the tiny solder spheres of each brick 105 begin to melt and reflow together.
FIG. 3 illustrates a solder joint 111 which contains a void 113 caused by volatized flux gases trapped within the solder joint 111 . Because the flux gases tend to migrate upwardly, any flux gases trapped within the solder joint 111 tend to migrate upwardly toward the bottom surface of the BGA component 101 , thereby becoming trapped and forming a void at the contact point of the solder joint 111 and the BGA component body 101 . As discussed above, such voids cause problems in the reliability, functionality and structural durability of the BGA component 101 .
FIGS. 4A and 4B illustrate two typical prior art designs for solder paste bricks 105 a and 105 b. The shape of the solder paste brick 105 a is that of a square or a rectangle while that of the solder paste brick 105 b is a circular disk. As will be explained in further detail below, these prior art solder paste bricks shapes are not conducive to reducing voiding in the solder joints formed during the reflow soldering process.
FIG. 5 illustrates one embodiment of an improved solder paste brick design in accordance with the invention. This solder paste brick 200 is in the shape of a crescent, similar to that of a quarter moon. This shape is advantageous in that it allows a sufficiently large volume of solder paste to be positioned within a pad of a PCB so as to hold, or attach, a BGA component to the PCB before and during the reflow solder process, while providing a contact point along a portion of an inside edge 213 for making contact with a solder ball terminal of the BGA component. As will be described in further detail below, by providing a contact point along a portion of the inside edge 213 of the solder paste brick 200 , the invention facilitates the escape of volatized flux gases from within the solder paste brick 200 during a reflow soldering process. The improved solder paste brick 200 has a first tapered end 201 and a second tapered end 203 with a middle portion 205 which is integral to the first and second tapered ends, 201 and 203 , and which is positioned therebetween. The solder paste brick 200 also includes a top surface 207 and a bottom surface (not shown) and first and second side surfaces 209 and 211 , respectively. The solder paste brick 200 also includes an edge 213 formed between the top surface 207 and the first side surface 209 .
It is advantageous that the solder ball contacts the solder paste brick 200 along the edge portion 213 rather than having such contact occur across the top surface, because during the soaking temperature phase and the beginning of the reflow phase discussed above, volatized flux gases escape from the top surface 207 as well as the side surfaces 209 and 211 of the brick 200 . As can be appreciated, if a solder ball terminal is directly on top of the top surface 207 of the solder paste brick 200 , as volatized flux gases migrate upwardly, there is a substantial probability that these flux gases will migrate up into the solder ball terminal itself as it begins to melt during the reflow phase of the process. This can cause substantial voiding at the base of the solder joint where it meets the BGA component. Therefore, by placing the solder ball terminal at a position where it only touches the edge 213 of the solder paste brick 200 , such upwardly migrating flux gases have a significantly better chance to escape from the volume of the solder paste brick 200 without migrating into the solder ball terminal as it begins to melt.
Referring to FIGS. 6A-6C, one can see the advantages of the crescent shape solder brick 200 over the prior art solder bricks 105 a and 105 b of FIG. 4 . In particular, it is noted that the shaded regions 115 a, 115 b and 215 represent contact points between the respective solder paste bricks 105 a, 105 b or 200 and a solder ball terminal (not shown) of a BGA device. As can be seen from the various shaded regions on each of the solder paste bricks, the crescent shape of solder brick 200 affords a minimum contact area with the solder ball terminal, at the edge 213 of the solder paste brick 200 , thereby minimizing the area in which volatized flux gases may migrate upwardly into the solder ball terminal as it melts to form a solder joint. Additionally, the crescent shape of the solder paste brick 200 provides an adequate volume of solder paste onto the PCB pad 217 in order to hold the BGA device on the PCB while minimizing the contact surface area between the solder ball terminal and the brick 200 .
It can be seen from FIGS. 6A-6C that in order to minimize the contact surface area between a solder ball terminal and the prior art solder paste bricks 105 a and 105 b, a solder ball terminal would have to be moved a distance A or B, respectively, in order to make contact with an edge of the solder paste brick 105 a or 105 b. The distances A and B may be as long as 15-20 mils. Such a shift in the position of the solder ball terminals would cause misalignment problems between the pads 107 a, 107 b and the solder ball terminals. However, with the use of the crescent-shaped solder paste brick 200 of the present invention, one can see that there is no need to shift the position of a BGA device so as to have a solder ball terminal of the BGA device make contact with only an edge portion 213 of the solder paste brick 200 .
FIG. 7 illustrates one embodiment of a method of arranging multiple solder paste bricks 200 onto the pads 217 of a PCB in order to hold the solder ball terminals (not shown) of a BGA component in proper alignment with the pads 217 . The crescent shaped bricks 200 are arranged such that each brick 200 within an adjacent row or column of pads, is rotated 90 degrees with respect to one another. It is appreciated that by arranging the bricks 200 in this fashion, the solder paste bricks 200 hold a BGA component in alignment with the pads 217 of the PCB such that the BGA component is secured against moving, or sliding, in each of the directions designated as “N,” “S,” “E,” or “W” in FIG. 7 . However, it is understood that adjacent bricks need not be rotated exactly 90 degrees with respect to one another. Other angles of rotation are contemplated by the invention. Depending on the size and shape of the bricks 200 , adjacent bricks may be rotated 180 degrees, for example, with respect to one another.
FIGS. 8A-8C are top views of different solder paste brick shapes which illustrate further advantages of the shape of the solder paste brick 200 when compared to that of the solder paste bricks 105 a and 105 b. The arrows 117 a, 117 b and 217 represent the relative distances that volatized flux gases must travel as they pass in the indicated directions within the bricks in order to escape the side surfaces of the solder paste bricks 105 a, 105 b and 217 , respectively. An average distance that flux gases must travel to escape a side surface of the brick 105 a can be represented by the distance A. Similarly, B and C represents the average distances flux gases must travel to escape a side surface of the bricks 105 b and 200 , respectively. As can be seen from FIGS. 8A-8C, assuming the size of each of the solder paste brick designs are accurately scaled with respect to each other, the average distance C that flux gases must travel in order to escape from side surfaces of the solder paste brick 200 is much shorter than the average distances A and B that flux gases must travel in order to escape from side surfaces of the solder paste bricks 105 A and 105 B, respectively. Consequently, volatized flux gases which are formed during the soaking temperature phase and migrate out of the solder joint area during both the soaking temperature phase and the reflow phase, have a much shorter distance to travel when using the solder paste brick 200 compared to the prior art solder bricks 105 a and 105 b. A shorter distance correlates to a shorter time required for the volatized flux gases to migrate outwardly and therefore allows more of the flux gases to escape during the soaking temperature phase discussed above. Therefore, the improved solder paste brick 200 shown in FIG. 8C, not only promotes the escape of volatized flux gases via the top surface of the solder paste brick 200 , as discussed above with reference to FIGS. 5 and 6 A- 6 C, but also improves the rate at which volatized flux gases may escape via the side surfaces of the solder paste brick 200 , as shown in FIGS. 8A-8C.
FIGS. 9A and 9B show alternate embodiments of the invention. FIG. 9A shows a solder paste brick 300 which is in the shape of a “C”. FIG. 9B shows a solder paste brick 400 which is in the shape of a square or block “C”. The configurations illustrated in FIGS. 9A and 9B offer advantages over the prior art in that they provide for increased escape of volatized flux gases that may escape via the top and side surfaces of the respective solder paste bricks. These irregularly shaped structures are just one of many such structures that can provide the advantage of the invention. As used herein, the term “irregularly shaped structure” refers to any structure that is not circular, square or oblong and which allows a solder ball terminal of a BGA device to make contact with an edge portion of a corresponding solder paste brick having such an irregularly shaped structure, while further allowing proper alignment between the solder ball terminals of the BGA device and the pads of a printed circuit board. One can readily envision modifications of these shapes as well as other shapes for providing the advantages and functionality described herein.
The invention as described above provides an improved solder paste brick which significantly reduces the amount of voiding in solder joints formed between BGA devices and the etched pads of a PCB. By reducing the surface area in which a ball terminal of the BGA device makes contact with a top surface of the solder paste brick, the probability that volatized flux gases will migrate upwardly into the solder ball terminal as it begins to melt is significantly reduced. Furthermore, the shape of the improved solder paste brick reduces the distance that flux gases must travel in order to escape from the side surfaces of the brick, thereby allowing a greater volume of flux gases to escape, consequently reducing the amount of flux gases which may become trapped within the solder joint. The shape of the improved solder paste brick also allows an adequate amount of solder paste to be deposited on each pad in order to hold a BGA device in position atop a PCB before and during reflow processing. Finally, the shape of the improved solder paste brick is configured such that the solder ball terminals may make contact with only an edge of the brick and remain in proper alignment with their corresponding pads.
The invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive and the scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope. | A method of soldering a ball grid array device onto a circuit board which includes: positioning a solder paste brick on top of a contact pad of the circuit board, said solder past brick defining an irregularly shaped structure such that a majority of a top surface of the solder paste brick is not in contact with the solder ball terminal, wherein volatized flux gases formed during heating escape via the top surface without migrating upwardly into the solder ball terminal; attaching the ball grid array device onto the circuit board such that a solder ball terminal of the ball grid array device makes contact with a portion of an edge of the solder paste brick while remaining substantially aligned with a center of the pad; and heating the ball grid array device and the circuit board so as to melt the solder ball terminal and the solder paste brick, thereby forming a solder joint between the ball grid array device and the circuit board. | 8 |
This is a continuation of U.S. patent application Ser. No. 08/074,083, filed Jun. 8, 1993, now U.S. Pat. No. 5,448,760.
BACKGROUND OF THE INVENTION
1. Technical Field
This invention relates to wireless subscriber systems and, more particularly, the use of devices for granting or denying access to the wireless subscriber system.
2. Discussion
Some wireless subscriber systems utilize identification codes which are transmitted by wireless subscriber units along with other data sent to a receiver/transmitter site, base station, or cell. Electronics associated with the receiver/transmitter site can identify the wireless subscriber unit by the identification code. The identification codes can be used for billing the wireless subscriber unit for "air time" on a subscriber system or telephone exchange in addition to a basic monthly rate.
Such identification codes can be intercepted during an authorized user's transmission to the subscriber service or telephone exchange. The identification codes can then be programmed into an unauthorized wireless subscriber unit allowing the fraudulent user to gain access to the telephone exchange. The use of the subscriber service or telephone exchange by the unauthorized user is usually incorrectly billed to the authorized user and, of course, the operators of the subscriber system or telephone exchange are typically unable to collect the basic monthly rate from the unauthorized user.
Other wireless subscriber units do not automatically transmit an identification code during transmission. Identification of these wireless subscriber units is desirable when they are interfering with the transmission of other users, when they are being operated in a clandestine manner, or when they are otherwise being misused.
In an effort to address the above problems, radio fingerprinting was developed in the 1940's and 1950's. Oscilloscope photos or hand drawings of amplitude or frequency-detected turn-on transients, turn-off transients, and a final resting frequency of received radio transmitter signals were prepared. The photos or drawings reflect the damping factor and natural period of the radio transmitter and were visually compared to previous measurements to identify the radio transmitter. However radio fingerprinting became more difficult beginning in the 1960's due to an increasing number of radio transmitters and to manufacturing consistency of modern day radio transmitters. Thus, the turn-on transients, turn-off transients, and final resting frequency of the radio transmitters became far less distinguishable from each other using the radio fingerprinting method.
In U.S. Pat. No. 5,005,210 to Ferrell, a turn-on transient of a frequency demodulated waveform from a transmitter is captured and analyzed. Transmitters are identified by measuring signal phase of the turn-on transient or phase response of the turn-on transient with respect to a predetermined frequency. Commercial devices in accordance with Ferrell have captured the turn-on transient in a microcomputer for visual comparison by a user to subsequent captured turn-on transient. Point-by-point comparison of the digitized turn-on transient by the microcomputer has proven to be very difficult and unreliable because the turn-on transients are not exactly the same for successive turn-ons of the same transmitter. Consequently, visual comparison has been used. The system in Ferrell is simply a computerized version of the radio fingerprinting of the late 40's and 50's and does not meet the needs of modern subscriber systems adequately. Visual comparison is not practical in large subscriber systems due to customer expectations of fast access and due to excessive cost of visual comparison. Additionally, other portions of a transmitter's signal contains information having much greater transmitter discrimination/identification value.
Cellular telephone systems encounter similar problems as those described above. Cellular telephones have an identification code including an electronic serial number (ESN) and a mobile identification number (MIN) assigned to each phone. When the cellular telephone user initiates a call, the telephone transmits the identification code assigned to the phone for billing and call authorization purposes.
Tampering with the phone to alter the MIN or ESN was supposed to result in an inoperable phone. However, fraudulent persons devised ways to obtain the identification code of an authorized cellular telephone and to input the numbers into an unauthorized cellular telephone. The unauthorized cellular telephone could be used for "free" while charges for the calls were billed to the authorized user. The unauthorized users also did not pay the basic monthly rates. Unfortunately, no other provision for user identification was typically built into the cellular telephone system.
Alternate methods proposed were unacceptable irritations to the users or were vulnerable to being defeated by fraudulent persons. For example, one proposed method includes a request for a user personal identification number (PIN) each time a call is made. The PIN could be transmitted on a different frequency. However, some users will be irritated by the PIN request and change to a different carrier who does not require PIN's.
PIN systems also presuppose that the authorized user desires to maintain the PIN number in secrecy. Even if PIN systems are made universal, they are still vulnerable to interception by fraudulent persons.
Other proposed methods include operator interaction with each caller for positive personal identification and per call requests for credit card numbers. However, these methods are economically unfeasible and are still subject to the same problems as the PIN method. Any system which requires identification data to be transmitted from the cellular telephone to the cell sites can be intercepted, copied, and used to gain unauthorized access.
In summary, any proposed solution must allow easy access while still providing protection to the operator of the subscriber service or telephone exchange.
SUMMARY OF THE INVENTION
In a first form of the invention, a transmitter identification device includes a plurality of transmitters each for generating a transmitter signal with internal data traits and external signal traits. A receiver located remote from the transmitters receives the transmitter signal. A characterizing device connected to the receiver characterizes one of the transmitters and generates a plurality of characterizing signals for the one transmitter. The characterizing device generates the plurality of characterizing signals by measuring features of the external signal traits of said one of said transmitters from at least one of a first category including variations of specified parameters of said one of said transmitter, and a second category including variations in non-specified parameters. A converter connected to the characterizing device converts the plurality of characterizing signals into a security pattern. The security pattern is used to identify said one of said transmitters.
In another feature of the invention, a historic security pattern storing device stores historic security patterns for a plurality of transmitters. A first comparator connected to the converter and the historic security pattern storing device compares the security pattern of said one of said transmitters to said plurality of historic security patterns stored in said historic security pattern storing device.
It is still another feature of the invention that the first comparator generates a confidence level indicating a likelihood that one of said transmitters also generated the historic security pattern.
In still another feature of the invention, the confidence level generated by the first comparator indicates a mismatch condition, a possible mismatch condition, and a match condition.
In another embodiment, apparatus for identifying wireless subscriber units and for granting or denying access to a subscriber service includes a plurality of wireless subscriber units each for generating a wireless subscriber signal including internal data traits and external signal traits and for receiving a receiver/transmitter signal. The internal data traits include an identification code. A receiver/transmitter is located remote from the wireless subscriber units. The receiver/transmitter receives the wireless subscriber signal and transmits the transmitter/receiver signal. A characterizing device is connected to the receiver/transmitter and generates a plurality of characterizing signals for one of said wireless subscriber units. The characterizing device generates said plurality of characterizing signals by measuring features of said external signal traits from at least one of a first category inducing variations of specified parameters of said one of said wireless subscriber units, a second category including variations in non-specific parameters, and a third category including variations in reactions or responses to interrogations. A converter connected to the characterizing device converts the characterizing signals to a security pattern. The security pattern and the identification code are used to identify said one of said wireless subscriber units.
The apparatus for identifying wireless subscriber units can further include a device for storing historic security patterns for said one of said wireless subscriber units and a first comparing device connected to the converter and the storing device for comparing the security pattern to the historic security pattern corresponding to the identification code of said one of said wireless subscriber units.
The first comparing device generates a confidence level indicating a likelihood that said one of said wireless subscriber units also generated the historic security pattern.
Another feature of the invention is an access device for granting or denying access to one of said wireless subscriber units to said subscriber system based upon said confidence level.
In another feature of the invention, the confidence level generated by the first comparing device indicates a mismatch condition, a possible mismatch condition, and a match condition.
In still another feature of the invention, a device stores a fraudulent user history for a plurality of fraudulent wireless subscriber units. A second comparing device connected to the first comparing device compares the security pattern of said one of said wireless subscriber units to the fraudulent user history when the first comparing means generates the confidence level indicating the possible mismatch condition. The second comparing device generates a match signal or a mismatch signal.
In yet another feature of the invention, the access device grants access to said one of said wireless subscriber units if the first comparing device generates the confidence level indicating the match condition, or if the first comparing device generates the confidence level indicating the possible mismatch condition and the second comparing device generates the mismatch signal.
In a further feature of the invention, the access device denies access to one of said wireless subscriber units if said first comparing device generates the confidence level indicating the mismatch condition, or if the first comparing device generates the confidence level indicating the possible mismatch condition and the second comparing device generates the match signal. The fraudulent user history storing device is updated with the security pattern of one of said wireless subscriber units when the access device denies access.
BRIEF DESCRIPTION OF THE DRAWINGS
The various advantages of the present invention will become apparent to those skilled in the art after studying the following specification and by reference to the drawings in which:
FIG. 1 is a functional block diagram of a wireless; subscriber system according to the prior art;
FIG. 2 is a functional block diagram of a wireless subscriber system incorporating the present invention;
FIG. 3A is a functional block diagram of a security pattern generation device;
FIG. 3B is a functional block diagram of a security pattern algorithm located in memory associated with the security pattern generation device;
FIG. 4 is a functional block diagram of a RF shift characterizing routine located in the memory of the security pattern generation device;
FIG. 5A is a first waveform output of a first wireless subscriber unit generated by a time align and averaging block in FIG. 4;
FIG. 5B is a first frequency histogram of the first waveform output of FIG. 5A generated by a frequency histogram block of FIG. 4;
FIG. 6A is a second waveform output of a second wireless subscriber unit generated by the time align and averaging block of FIG. 4;
FIG. 6B is a second frequency histogram of the second waveform output of FIG. 6A generated by the frequency histogram block of FIG. 4;
FIG. 7 is a functional block diagram of an alternate RF characterizing routine located in the memory of the security pattern generation device;
FIG. 8A is the first waveform output with straight line segments being fit thereto by a least-means-squared method according to the RF characterizing routine of FIG. 7;
FIG. 8B is the second waveform output with straight line segments being fit thereto by the least-means-squared method according to the RF characterizing routine of FIG. 7;
FIG. 9 is a functional block diagram of a request for power change characterizing routine located in the memory of the security pattern generation device;
FIGS. 10A, 10B and 10C are waveform diagrams of a typical wireless subscriber signal including a pre-carrier portion, a pre-amble portion, a text portion, and a post-carrier portion;
FIG. 11 is a raster scan plot and a plot of a wireless subscriber signal; and
FIG. 12 is functional block diagram of a confidence level generation routine located in a memory of a confidence level generating device.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In FIG. 1, a wireless subscriber system 10 of the prior art is shown. The wireless subscriber system 10 includes multiple wireless subscriber units 14, 16, 18, 20, which can be cellular telephones or other transmitters. Each wireless subscriber unit 14, 16, 18, 20 transmits a wireless subscriber signal and receives a transmitter/receiver signal (both are identified in FIGS. 1 and 2 with reference numbers 24, 26, 28, 30, respectively) to one of a plurality of transmit/receive sites 34 and 36 which generate the transmitter/receiver signal and which can be cell stations for the cellular telephones.
The plurality of transmit/receive sites 34 and 36 are typically spaced throughout a service area. The wireless subscriber signals 24 and 26 from the wireless subscriber units 14 and 16 are transmitted to and received by the transmit/receive site 34 due to proximity thereto. After initial turn-on transients die out, the wireless subscriber signals and the transmitter,receiver signals each include internal data traits and external signal traits. The internal data traits of the wireless subscriber signal can include digitized or analog voice data, video data, subscriber system protocol data, etc. Other types of data will be readily apparent. Similarly, the wireless subscriber signal 28 and 30 from the wireless subscriber units 18 and 20 are transmitted to and received by transmit/receive site 36 due to proximity thereto.
As the wireless subscriber units 14, 16, 18, 20 move about in the service area, an access control and switching device 40 "hands off" the wireless subscriber signals 24, 26, 28 and 30 from one transmit/receive site to another. For example, as the wireless subscriber unit 14 travels away from transmit/receive site 34 towards transmit receive site 36, the access control and switching device 40 transfers transmitting and receiving functions from the transmit/receive site 34 to the transmit/receive site 36.
The internal data traits of the wireless subscriber signals 24, 26, 28 and 30 from the wireless subscriber units 14, 16, 18, 20 can include a n identification code which can include a mobile identification number (MIN), an electronic serial number (ESN), a manufacturer's code (MAN), and a station class mark (SCM). "Identification code" as used herein means information in the wireless subscriber signal sent by a wireless subscriber unit to identify itself. Prior to granting access to a subscriber service or telephone company 46, an authorized user verification device 50 connected to the access control and switching device 40 verifies the identification code to determine if the wireless subscriber unit, for example wireless subscriber unit 14, is an authorized user by comparison with an authorized user list 52.
If the wireless subscriber unit 14 is on the authorized user list 52, the access control and switching device 40 grants access to the subscriber service or telephone company 46. If the wireless subscriber unit is not on the authorized list, the wireless subscriber unit is placed on an unauthorized user list 54. Both the authorized and unauthorized user list 52 and 54 can be stored in memory 58 associated with the authorized user verification device 50.
The access control and switching device 40 can be located at the same location as the subscriber service or telephone company 46 or remote therefrom.
In FIG. 2, a subscriber system 100 according to the present invention is shown. A security pattern generation device 102 is connected to modified transmit/receive sites 104 and 106. Note that an unmodified transmit/receive site 108 without the security pattern generation device 102 may also be connected to the access control and switching device 40. The security pattern generating device 102 measures a plurality of unique features of the external signal traits of the wireless subscriber unit which is currently transmitting and receiving the wireless subscriber signal to and from the transmit/receive site attached to the security pattern generating device 102. The unique features measured by the security pattern generating device 102 identify the wireless subscriber unit from other authorized or unauthorized wireless subscriber units. Such identification of the wireless subscriber unit is hereinafter called "characterizing" (also characterization) and is described further below.
The security pattern generating device 102 converts the characterization into a security pattern which is typically a multi-digit number. The security pattern is combined with the identification code (or parts thereof, for example the MIN or ESN) of the wireless subscriber unit into a combined security code. The combined security code is output to the access control and switching device 40 and then to a modified authorized user verification device 110 which can have a memory 114 associated therewith for storing an authorized user list 163 and an unauthorized user list 118. The modified authorized user verification device 110 can be designed to accept either the identification codes from the unmodified transmit/receive site 108 or the combined security code from the modified transmit/receive sites 104 and 106.
Since the subscriber system is already set up for transmitting the identification code (for example, both the ESN and the MIN which can be ten digit numbers) from each transmit/receive site to the access control and switching device 40 and then to the authorized user verification device 50 (or modified authorized user verification device 110), it is desirable to combine the characterization with the identification code to minimize system changes.
When the modified authorized user verification device 110 receives identification codes from the unmodified transmit/receive sites 108, the modified authorized user verification device 110 looks only for the identification code and performs an identification procedure similar that described above in conjunction with FIG. 1. When the modified authorized user verification device 110 receives the combined security code from the modified transmit/receive sites 104, 106, the modified authorized user verification device 110 transmits either the combined security code or the identification code and the security pattern to a confidence level generation device 120 which can be located locally or remote from the modified authorized user verification device 110. The security pattern and identification code can also be combined into the combined security code for the purpose of sending minimum data through the access control and switching device 40 and the modified authorized user verification device 110.
Alternatively, a separate data link 121 can be provided between the security pattern generating device 102 and the confidence level generating device 120. If the separate data link 121 is provided, the identification code (or parts thereof) need not be combined with the security pattern. The separate data link 121 can transmit the identification code (or parts thereof) and the security pattern to the confidence level generation device 120 separately.
The confidence level generation device 120 is connected to a security pattern history storage device 124 and a fraudulent user history storage device 125 both of which can be located locally or remote from both the modified user verification device 110 and/or the confidence level generation device 120. The confidence level generation device 120 compares the security pattern in the combined security code of the wireless subscriber units 14, 16, 18, 20 to previously recorded security patterns (for each wireless subscriber unit) stored under the identification code, the ESN or the MIN in a security pattern history storage device 124. Depending on the correlation between the recently transmitted security pattern and the historic security patterns, the confidence level generation device 120 generates a confidence level indicating a probability that the wireless subscriber unit generating the security pattern is or is not the same as the wireless subscriber unit which generated the security patterns stored in the security pattern history storage device 124. The modified authorized user verification device 110 determines whether the requesting wireless subscriber unit generating the security pattern is or is not an authorized user based upon the confidence level signal and can grant or deny access to a subscriber service or telephone exchange 46. Alternatively, the confidence level generation device 120 can include access means for granting or denying access to the subscriber service or telephone exchange 46 based upon the confidence level signal.
Access can be denied in many different ways. For example, when either the confidence level generation device 120 or the modified authorized user verification device 110 determines that access should be denied, for example because the wireless subscriber unit is fraudulently using a MIN/ESN of another wireless subscriber unit, the confidence level generation device 120 or the modified authorized user verification device 110 can output (internally or via external connection 126) commands to the transmit/receive site. Typically when a request for service is made (e.g. the fraudulent wireless subscriber requests connection to a second wireless subscriber unit), the transmit/receive site transmits the ESN/MIN used by the requesting wireless subscriber unit on a forward control channel along with a command to change to a specified voice channel assigned to the wireless subscriber unit. The requesting wireless subscriber unit typically dwells in a mode watching the forward control channel for the command to change to the specified voice channel. The transmit/receive site and the confidence level generation device or the modified authorized user verification device automatically follows the wireless subscriber unit to the specified voice channel. A simulated or actual wireless subscriber unit associated with the confidence level generation device and the modified authorized user verification device can issue a service termination command to the transmit/receive site and service is discontinued to the fraudulent wireless subscriber unit. The simulated or actual wireless subscriber unit simulates a command by the fraudulent wireless subscriber unit to hang-up before the transmit/receive site connects the fraudulent wireless subscriber unit to the second wireless subscriber unit.
Alternate methods of denying access will be readily apparent. For example, if a first wireless subscriber unit having a first MIN/ESN is currently using the subscriber service and moments later the wireless subscriber unit having the first MIN/ESN requests service (e.g. call collision), some modified transmit/receive sites are designed to disconnect service to the first wireless subscriber unit. The confidence level generation device 120 or the modified authorized user verification device 110 can deny access to a wireless subscriber unit simply by requesting service at the modified transmit/receive site using the ESN/MIN of the wireless subscriber unit to be denied service.
In FIG. 3A, a block diagram depicts the security pattern generation device 102 which includes an I/O device 127, a microprocessor 128, and memory 130. Alternatively, the security pattern generation device 102 can be a program stored and executed by the transmit/receive site 104. The confidence level generating device 120 can similarly have an I/O device, a microprocessor, and memory.
In FIG. 3B a security pattern algorithm 132 in the memory 130 is shown. In blocks 134-137, a characterizing routine controls measurements on the wireless subscriber signal from first, second and third feature categories described in detail below and generates a security pattern, for example a multi-digit number wherein each digit or group of digits represents a measured feature. Each digit or group of digits could also represent deviation of the measured feature from typical values as described below.
In block 138, the security pattern generation algorithm 132 determines the identification code of the wireless subscriber unit. In block 139, the security pattern generation algorithm 132 combines the security pattern generated by the characterization routine with the identification code generated by the block 138 into the combined security code. The combined security code is then output by the security pattern generation device 102 and/or the transmit/receive site 104 to the access control and switching device 40 as described above.
Alternatively, the security pattern and the identification code (or portions thereof; for example, the MIN and/or the ESN) are sent separately via the separate data link 121 to the confidence level generation device 120. If the separate data link 121 is used, block 139 may be omitted.
CHARACTERIZATION AND SECURITY PATTERN GENERATION
Characterization of a wireless subscriber unit by the characterizing algorithm 132 in the security pattern generation device 102 can be accomplished by measuring features of the external signal traits of the wireless subscriber signal from preferably three feature categories. The first feature category includes natural variations of specified parameters of the wireless subscriber unit within or outside specification tolerances. The specified parameters of the external signal traits of the wireless subscriber signal can be expected to range up to twice the specified tolerance. For example, one specified parameter measured could be bit rate, which typically has a tolerance of ±1 Hz of a nominal value. A second specified parameter could be the transmitting or receiving RF, which typically has a tolerance of ±2 kHz from channel center. A third specified parameter could be RF shift which typically has a tolerance of ±200 Hz of 16 KHz. Other specified parameters will be readily apparent.
The second feature category includes variations in no n-specified parameters.
For example, the non-specified parameter could be slope of mark or space frequencies. Other non-specified parameters will be readily apparent.
The third feature category includes variations in reactions or responses to interrogations by the security pattern generation device 102. For example, the security pattern generation device 102 can request the wireless subscriber unit to make an RF power change. The security pattern generation device 102 can then measure the delay in the wireless subscriber unit's response and/or the change in amplitude of the wireless subscriber unit in relation to the change requested. Other types of interrogations, commands and responses will be readily apparent.
In FIG. 4, a functional block diagram of a RF shift characterizing routine 140 (the first feature category) forming part of the security pattern generating device 102 is shown. A double bit sample capture block 144 captures double bit words (e.g. two 0's (space) followed by two 1's (mark)) from the wireless subscriber signal received by the transmit/receive site 104. Alternatively, the wireless subscriber signal received by the transmit/receive site 104 can be recorded in memory and thereafter retrieved by the double bit sample capture block 144. A time align and averaging block 148 generates a first waveform output 152 (with a channel center at 153) shown in FIG. 5A which includes multiple time aligned and averaged double bit words from the wireless subscriber signal 24.
A frequency histogram block 154 generates a frequency histogram graphically depicted in FIG. 5B. The frequency histogram block 154 includes a predetermined number of discrete frequency divisions 156 and samples the first waveform output 152 from the time align and averaging circuit 148 at a sample frequency T. The frequency histogram block 154 generates a frequency histogram 158 in FIG. 5B which depicts the number of samples at each discrete frequency (captured at each sample frequency T). Peaks 160 in the frequency histogram 158 identify a mark frequency 164 and a space frequency 168.
A mark and space frequency peak locator block 174 determines the frequency of the peaks 160 in the frequency histogram 158 to determine the mark and space frequencies 164, 168. An RF shift determining block 178 subtracts the mark and space frequencies 164, 168 to generate a measured RF shift of the wireless subscriber unit.
A RF shift deviation block 180 compares the measured RF shift with a standard or mean RF shift and generates a number representing deviation. When measuring RF shift of the wireless subscriber unit, expected values of RF shift are typically ±200 Hz of 16 kHz but can range on a scale between 12 kHz and 20 kHz. A RF shift scale for RF shift values is determined. The scale from 12 kHz to 20 Khz can be divided into equal divisions.
For example, the scale 12 Khz to 20 kHz can be divided into 99 equal divisions. Measured RF shift values less than 12 kHz could be assigned the deviation number 01, values greater than 20 kHz could be assigned the deviation number 99, and values around 16 kHz could be assigned the deviation number 50. Values between 12 kHz and 16 kHz and 16 kHz and 20 kHz can be assigned the deviation numbers between 02-49 and 51-98 respectively. If desired (e.g. to provide better differentiation of the RF shift values) the scale from 12 kHz to 20 kHz can be divided into unequal divisions or skewed. Scales from 1-9, 1-F (hexadecimal), 1-999, etc. can also be used. Other methods of assigning numbers to the range of RF shift values are readily apparent.
In FIG. 6A, a second waveform output 188 generated by sampling another wireless subscriber unit does not define mark and space frequencies as distinctly as the first waveform output 152 in FIG. 4A. A frequency histogram smoothing block 192 can be used to further define the mark and space frequencies by generating a modified frequency histogram 194 (see FIG. 6B) incorporating dotted line 196.
In FIGS. 7, 8A and 8B an alternate method of characterizing RF shift (the first feature category) and a method of characterizing RF Mark and space slope (the second feature category) is shown. In FIG. 7, a functional block diagram of alternate RF characterizing routine 210 forming part of the security pattern generation device 102 is shown. The alternate RF characterizing routine 210 utilizes the double bit sample capture block 144 and the time align and averaging block 148 of FIG. 4.
A space frequency portion 214 of waveform 216 in FIG. 8A and a waveform 217 in FIG. 8B is divided into times A, B and C. In block 218 (FIG. 7), a straight line 220 is rotated about a point at time B and fit to the space frequency portion 214 between time A and time C by a least-means-squared method. In block 224, RF space slope is determined (RF space slope approximately 0 in FIG. 8A; RF space slope>0 in FIG. 8B).
A mark frequency portion 230 of the waveform :216 in FIG. 8A and the waveform 217 in FIG. 8B is divided into times D, E, and F. In block 232 (FIG. 7), a straight line 234 is rotated about a point at the time E and fit to the mark frequency portion 230 between the time D and the time F by the least-means-squared method. In block 236, RF mark slope is determined (RF mark slope approximately 0 in FIG. 8A; RF mark slope<0 in FIG. 8B). In blocks 240 and 242, corresponding points time points on lines 220 and 234 are chosen on the waveforms 216 and 217 to determine RF shift. For example, time points B and E on the waveform 216 can be chosen and the frequencies at the time points B and E subtracted to determine the RF shift. Alternatively time points A and D or C and F can be chosen to maximize information and discrimination of the wireless subscriber units. In block 180, the RF shift deviation is determined as described above.
Note that the RF mark and space slopes were determined by the alternate RF characterizing routine 210 at blocks 224 and 226. In block 246, mark and space slope deviation are determined in a manner analogous to the RF shift deviation determination described above.
In FIG. 9, a request for power change characterizing routine 260 (the third feature category) forming part of the security pattern generation device 102 is shown. In block 262, a request for RF power change is transmitted by the transmit/receive site 104 to the wireless subscriber unit. In blocks 264 and 266, delay in the wireless subscriber unit's response is measured and power change response time deviation is determined in a manner analogous to the RF shift deviation described above. In blocks 270 and 272, RF amplitude change of the wireless subscriber signal is measured and power change amplitude deviation is determined in a manner analogous to the RF shift deviation described above.
Additional methods of converting measured features of the external signal traits from the three categories to numerical values will be readily apparent. For example, in FIGS. 4-8 inclusive, single length bits (one "0" or space followed by one "1" or mark) could be used to determine RF shift of the wireless subscriber unit. Alternatively, a frequency histogram could be generated by sampling all bits during a given period. Additionally, RF shift could be inferred from measured intersymbol interference. Intersymbol interference can be determined by measuring time offset between time combs (see description below) fit to all single bit length to double bit length transitions versus all double bit length to single bit length transitions (however, baud bias corrections may be required).
The characterizing routine 134 (FIG. 3B) generates the security pattern by combining the following: the RF shift variation from the RF characterizing routine 140 or from the alternate RF characterizing routine 210 (for example RF shift deviation=78); the RF mark and space slope deviations from the RF characterizing routine 210 (for example mark slope deviation=3, space slope deviation=5), and the RF power change response time and amplitude deviation from the power change characterizing routine 260 (for example power change time deviation=61, power change amplitude deviation=7). The characterizing routine combines the deviations into the security pattern 7335617 with the first two digits representing the RF shift deviation, the third and fourth digits representing the mark and space slope deviations, and the fifth, sixth and seventh digits representing the power change time and amplitude deviations.
The block 138 in the security pattern generation algorithm 132 in FIG. 3B determines the identification code, the MIN or the ESN of the wireless subscriber unit, for example a ten digit code 0001212345. The block 139 in the security pattern generation algorithm 132 combines the ten digit number (corresponding to the identification code, the MIN or the ESN) with the security pattern into the combined security code. For example, the security pattern could be added to the most significant digits of the identification code (or MIN or ESN) (without carry) to generate the ten digit combined security code 7836829345.
Other additional features in the three categories may also be measured (and deviations computed for the features) for incorporation into a security pattern. In FIGS. 10A-C, some of these additional features of the external traits are identified on a typical wireless subscriber signal 300 including a pre-carrier portion 302, a preamble portion 304, a text portion 306 and a post-carrier portion 308. Turn-on transient 310 preceding the pre-carrier portion 302 and turn-off transient 312 (FIG. 10C) following the post-carrier portion 308 are not used as a characterizing features due to limited wireless subscriber unit discrimination information and other considerations described above.
A dotting portion 314 with alternating marks 315 and spaces 316 follows a partially formed mark or space portion 31 7. A sync word 318 and a DCC word 320 follow the dotting portion 314. A first word 324 is repeated several times and follows the DCC word 320. The following are examples of other characterizing features which can be used:
1. PFS (Point of First Sync)--PFS 328 is an adjusted time of a first space to mark transition in the sync word 318. PFS is adjusted based on time of a tooth in TC1 (described below) nearest measured PFS.
2. PFD (Point of First Dot)--PFD 330 is defined as 3.000000 msec before the PFS 328.
3. PTN (Point of Turn-On)--PTN 334 is time of RF rise relative to the PFS 328. PTN 334 is a point of energy rise which occurs during the turn-on transient. PTN 334 is an amplitude/time detected characterizing feature.
4. PFW (Point of First Warning)--PFW 336 is a point of first warning that bits are about to start.
5. FMD (First Mark Dotting)--FMD 340 is the time of the first fully formed mark in the dotting word 308.
6. TMS (Third Mark Sync)--TMS 344 corresponds to a third mark in the sync word 318. Typically located between 0.2 msec after the PFS 328 and 0.3 msec after the PFS 328.
7. FBD (First Bit of Data)--FBD 346 occurs at a time of transition of a first bit of data in the first word 324. The transition typically occurs 1.8000 msec after the PFS 328.
8. LBZ (Last Bit of Data in word Z)--LBX (not shown) is a time of transition of a last bit of data in word Z. Typically occurs at (PFS 328 plus 1.8000 msec plus (Z times 4.8 msec).
9. LBD (Last Bit of Data)--LBD 350 is time of transition of a last bit of data in a last word of the text portion 306. Typically occurs at (PFS 328 plus 1.8000 msec plus (NAWC times 2.4 msec). NAWC is the number of additional words coming. NAWC is protocol typically located in several bits of the first word 324.
10. PTF (Point of Turn-Off)--PTF 352 corresponds to a time of energy drop to off condition.
11. PECL (Pre-Carrier Length)--PECL equals (PFS 328 minus 3.000000 msec minus PTN 334).
12. POCL (Post-Carrier Length)--POCL equals (PFS 328 minus LBD 350).
13. TC1 (Time Comb 1)--TC1 is a time comb fit (see description below) by a least-means-squared method of space to mark transitions without intersymbol interference (e.g. double length bit lengths on both sides (two spaces or 0's followed by two marks or 1's)).
14. TC2 (Time Comb 2)--TC2 is the time comb fit (see description below) by the least-means-squared method of mark to space transitions without intersymbol interference (e.g. double length bit lengths on both sides (two marks o 1's followed by two spaces or 0's)).
15. TTC1 (Time of Time Comb 1)--TTC2 is a time of a tooth in TC1 nearest the PFS 328.
16. TTC2 (Time of Time Comb 2)--TTC2 is a time of a tooth in TC2 nearest the PFS 328.
Security patterns can be generated, for example, by comparing the timing of any of the above events with a standard and by generating a number representing deviation. Other characterizing features will be readily apparent.
A time comb by the least-means-squared method is a fit of uniformly spaced intervals to external signal traits of a wireless subscriber signal to determine phase shift. For example, when the requesting wireless subscriber unit is transmitting the wireless subscriber signal 300, a phase change occurs at line 370 in FIG. 11) between the preamble portion 304 and the text portion 306. One method of performing the time comb is to use a raster scanning device which scans at a fixed rate. Each time a sampled waveform has a zero-crossing, a dot (generally at 372) is plotted at a location of an invisible raster scan at a time of the zero-crossing. If the time between zero-crossings is the same as the raster scanning period, then the dots will continue to be plotted on at in a similar vertical position. When a change in phase occurs, the vertical position also changes (at 374). The time of the phase change can be measured relative to the PFS 328. Time combs can be performed on other signal events, for example see items 13-16. Numerous other time combs can be performed. The above list is meant to be illustrative and not exclusive.
CONFIDENCE LEVEL GENERATION
As described above in conjunction with FIG. 2, the security pattern generation device 104 transmits the combined security code to the modified authorized user verification device 110 which can be located at the access control and switching device 40 location or remote therefrom. The modified authorized user verification device 110 looks for either the identification code from the transmit/receive site 108 (without the security pattern generation device 102) or the combined security code from the transmit/receive sites 104, 106 (with the security pattern generation device 102).
The modified authorized user verification device 110 separates the combined security code into the security pattern and the identification code (or the MIN or the ESN) and transmits each to the confidence level generation device 120. The modified authorized used verification device 110 could also transmit the combined security code to the confidence level generation device 120 for separation.
Alternatively, the security pattern and the identification code (or a portion thereof) can be sent directly from the security pattern generation device 102 to the confidence level generation device 120 via the separate data link 121.
The confidence level generation device 120 compares the security pattern of the requesting wireless subscriber unit to a security pattern stored in the security pattern history storage device 124 under the identification code (the MIN or the ESN) of the requesting wireless subscriber unit. Because the measured features of the same wireless subscriber unit can vary slightly from time to time, the digits in the security pattern representing the characterized features vary slightly. To alleviate this problem, the confidence level generation device 120 generates a confidence factor indicating a likelihood that the wireless subscriber unit generating the security pattern also generated the stored security pattern.
The confidence level generation device 120 outputs the confidence factor to the modified authorized user verification device 110 which decides whether to authorize access to the subscriber service or telephone company 46.
In FIG. 12, a logic diagram 400 to be executed by the confidence level generating device 120 and the security pattern history storage device 124 is shown. In block 402, a wireless subscriber unit requests access to the subscriber service 46. As described above, the security pattern generating device 102 generates the combined security code for the wireless subscriber unit by characterizing features of the external signal traits of the wireless subscriber unit, by generating a security pattern, and by combining the security pattern with the identification code (the MIN or the ESN). Combining the security pattern and the identification code (the MIN or the ESN) need not be done if a separate data link 121 is utilized.
The modified user authentication device 110 is modified to interact with the confidence level generating device 120. However, the modified authentication device 110 can still perform conventional fraud detection such as profiling and/or other conventional techniques, as depicted in block 404. The modified authentication device 110 (or the confidence level generating device 120) separates the combined security code into the security pattern and the identification code (the MIN or the ESN). Note that the security pattern can be obtained from the combined security code simply by subtracting the identification code (the MIN or the ESN). Alternatively, the separate data link 121 can be used.
If the wireless subscriber unit passes the conventional fraud detection performed by the modified user authentication device 110, then the security pattern is compared in block 408 to a security pattern stored in the security pattern history storage device 124 corresponding to the identification code (the MIN or the ESN) of the requesting wireless subscriber unit.
Each digit or digits of the security pattern correspond to characterizing features of the requesting wireless subscriber unit. Variations in each feature may occur between subsequent characterizations of the same wireless subscriber unit.
The first matching algorithm associated with block 408 determines a confidence level for the security pattern of the requesting wireless subscriber unit. The first matching algorithm could initially determine variations between each feature in the historic security pattern and each feature in the security pattern of the requesting wireless subscriber unit. The matching algorithm could then determine if the entire security pattern is a match, a possible mismatch, or a mismatch from the features tested by generating a confidence level representing probability of mismatch.
For example, a match could include confidence levels between 0% and 33%, a possible mismatch could include confidence levels between 34% and 66%, and a mismatch could include confidence levels between 67% and 100%.
In the example given above, the measured power change time deviation was 61. Assume that this value was previously stored as part of the security pattern in the security pattern history storage device 124 under the identification code (the MIN or ESN) of the requesting wireless subscriber unit. As the power change time deviation of the requesting wireless subscriber unit varies from 61 (the stored value), the confidence level percentage for this feature increases.
For example, if the power change time deviation for the requesting wireless subscriber unit was:
56 (or 66)--the feature confidence level for the power change time deviation could be 60%;
57 (or 65)--the feature confidence level for the power change time deviation could be 45%;
58 (or 64)--the feature confidence level for the power change time deviation could be 30%;
59 (or 63)--the feature confidence level for the power change time deviation could be 20%;
60 (or 62)--the feature confidence level for the power change time deviation could be 10%; or
61--the feature confidence level for the power change time deviation could be 0%.
The matching algorithm similarly determines confidence levels for other digits of the security pattern representing other features of the wireless subscriber unit. Finally the confidence levels for each of the features could be averaged or otherwise weighted to determine the confidence level for the security pattern of the requesting wireless subscriber unit. The weighing given to each feature and the confidence level percentage requirements for match, possible mismatch, and mismatch can be varied as desired. In addition, the confidence level generation device 120 could include an adaptive algorithm which automatically changes or customizes as a wireless subscriber unit develops a security pattern history. The security pattern history can be updated periodically to track changes in the external signal traits as the transmitter ages.
If block 408 determines a possible mismatch between the security pattern of the requesting wireless subscriber unit and the security pattern stored under the identification code (the MIN or the ESN) of the requesting wireless subscriber unit, an additional comparison is performed in block 412 between the security pattern of the requesting wireless subscriber unit and a fraudulent user history which contains characterizing codes of past fraudulent users. The security patterns in the fraudulent user history device are not searched by the identification code (the MIN or ESN) of the requesting user since the wireless subscriber unit may be changing the identification code (the MIN or the ESN) to fraudulently obtain access to the subscriber system 46.
A second matching algorithm performs a weighted comparison between the security pattern of the requesting wireless subscriber unit and the security patterns of multiple suspects stored in the fraudulent user history storage device 125. The fraudulent user history storage device contains data organized, for example, in suspect files. In cellular telephone systems, fraudulent users often change the MIN and ESN for their cellular telephone and obtain free access. When the fraudulent user cannot use the subscriber system after being detected for fraudulent use, the fraudulent user simply changes the MIN and ESN of his cellular telephone and obtains free access again.
However, the fraudulent users cannot change the features measured by the security pattern generating device 102. Therefore, the fraudulent user history device stores the security pattern of the fraudulent user when the fraudulent user is first detected.
If sufficient similarity exists between the features of the security pattern of the requesting wireless subscriber unit and the features of a fraudulent user security pattern (for example suspect #28) as determined in block 412, the fraudulent user history (for suspect #28) can be updated with a number called by the wireless subscriber unit, the identification code (the MIN or the ESN), the confidence level, and the security pattern of the requesting wireless subscriber unit (block 416). The requesting wireless subscriber unit is denied access to the subscriber system (block 418).
If insufficient similarity exists between the security pattern of the requesting wireless subscriber unit and the security pattern in the fraudulent user history device 125, the security pattern history stored under either the MIN or ESN is updated with the security pattern, the confidence level and the number called. The requesting wireless subscriber unit is granted access to the subscriber system (block 422). The confidence level is stored in the security pattern history storage device 124 for later use. For example, when an authorized user receives his phone bill and realizes that he/she did not make a call, the subscriber service operator can look up the confidence level. If the confidence level is high (e.g., indicating a higher probability of mismatch), the call can be removed from the bill.
If conventional authentication in block 404 determines that the requesting wireless subscriber unit is fraudulent, the fraudulent user history device is updated (or started if no prior fraudulent user history is recorded) in block 416 and the user is rejected in block 418.
If conventional authentication in block 404 determines that the requesting wireless subscriber unit is a suspected fraudulent user, then the security code of the requesting wireless subscriber unit is compared in block 430 with the characterizing code stored under the MIN or ESN of the requesting wireless subscriber unit.
The confidence level is generated in block 430 in a manner analogous to the confidence level described above. After comparing each feature in the security pattern of the requesting wireless subscriber unit with the security pattern stored in the security pattern history storage under the identification code (the MIN, or the ESN), possible mismatches and matches are sent to block 432. The security pattern is then compared to suspects in the fraudulent user history device 125 in a manner analogous to block 412.
If a match is not found between the security pattern of the requesting wireless subscriber unit and the fraudulent user history in block 432, the security pattern history device 124 is updated and the wireless subscriber unit allowed access to the subscriber service.
If a match is found between the security pattern of the requesting wireless subscriber unit and the fraudulent user history in block 432 or if the confidence level determined in block 430 indicates a mismatch, the fraudulent user history device 125 is updated (or started) in block 416. The requesting wireless subscriber unit is denied access to the subscriber system in block 418.
Another method of detecting fraudulent wireless subscriber units can be incorporated in the present invention. Use of the subscriber service by a wireless subscriber unit can be monitored by a usage profiling device executing on a microprocessor (analogous to FIG. 3A) associated with at least one of the access control and switching device 40, the confidence level generation device 120, the modified authorized user verification device 110, or the subscriber service 46 for various usage parameters. The usage parameter can include the number of times the monitored wireless subscriber unit requests access per day, the number of minutes the monitored wireless subscriber unit uses the subscriber service each day, the number of requests for access per hour, etc. Limits or thresholds for each usage parameter can be stored in memory for each MIN/ESN. Alternatively, a usage history for each MIN/ESN can be stored in the memory. The limits or thresholds can be selected by the subscriber service or the owner of a wireless subscriber unit or alternately programmed limits (e.g. based on past usage) can be used. If the user-selected or the programmed limits or thresholds are exceeded, an excess usage signal can be generated by the profiling routine. The excess usage signal is indicative of fraudulent use. As usage by the monitored wireless subscriber unit varies with time, the programmed limit can be updated, for example, on a monthly basis.
The profiling routine can also monitor additional usage conditions such as wireless subscriber units using multiple MiNs with the same ESIN, or multiple ESNs with the same MIN. The profiling routine can generate a multiple identity signal indicative of fraudulent use by the monitored wireless subscriber unit.
Upon generating the excess usage signal, or the multiple identity signal, the profiling routine can sever further access to the subscriber service in the manner described above. Alternatively, the profiling routine can be run in situations where the confidence level generation device determines the possible mismatch condition.
As can be appreciated, the present invention can be applied in various other circumstances. For example, a plurality of authorized radio transmitters can be operated at a select frequency. The authorized radio transmitters can be characterized and security patterns recorded for each radio transmitter in a security pattern history storage device. A receiver can intercept transmitter signals from both authorized and unauthorized radio transmitters operating at the select frequency. Security patterns generated by the authorized and unauthorized radio transmitters can be compared to the security patterns in the security pattern history storage device. Confidence levels can be generated for each of the authorized and unauthorized radio transmitters indicating a likelihood that a particular radio transmitter is or is not one of the authorized radio transmitters. As such, clandestine operation of the unauthorized radio transmitter may be detected.
The various advantages of the present invention will become apparent to those skilled in the art after a study of the foregoing specification and following claims. | A transmitter identification system to determine if cellular phones in a cellular phone system are authorized as distinguished from cloned phones, operated by fraudulent users, that are unauthorized. Components used in the manufacture of cellular phones vary slightly from one phone to anther so that, when the phones are used, the transmitter signals from each phone have different external signal traits. For each cellular phone call, the transmitter signal is received and characterized using a received set of features resulting from the external signal traits. The received set of features is compared with previously stored sets of Features in a database to determine if the call is authorized or unauthorized and, if unauthorized, the call is stopped and access to the fraudulent user is denied. | 7 |
BACKGROUND OF THE INVENTION
This invention relates to a method of and an apparatus for cleaning the air in clean rooms, clean booths, clean tunnels, clean benches, safety cabinets, aseptic rooms, bath boxes, aseptic air curtains, or clean tubes in the electronics industry, medicines industry, food industry, agricultural and forestry industries, medical facilities and precision machine industries.
Conventional air cleaning methods or apparatus in a room are generally classified into the following:
(1) a mechanical filter type (e.g., a HEPA filter), and
(2) a filtering type which charges fine particles electrically at a high voltage and collecting the particles electrostatically by means of a conductive filter (e.g., a MESA filter).
These types have the following drawbacks:
In the mechanical filter type, it is necessary to use a fine filter to improve the quality (the cleaning class) of the air. In this case, the pressure loss is high, the increase in pressure loss due to clogging is remarkable, the lifetime of the filter is short, and the maintenance, the management and the exchange of the filter are complicated. When the filter is exchanged, it is necessary to stop working during the exchange, and it takes a long time to recover the system which deteriorates the production efficiency.
The number of times for ventilations (the number of times for circulating the air by a fan) is increased to improve the quality, i.e., to raise the cleaning class of the air, but the cost of power increases.
Since the only purpose of the conventional filter method is to remove fine particles, it can be used as an industrial clean room, but as the filter always has pin-holes which leak part of the contaminated air, its use in a biological clean room is limited.
In the type for electrostatically collecting fine particles, a high voltage such as 15 to 70 kV is necessary in a preliminary charger to cause the system to increase in size, and there are safety, maintenance and management drawbacks.
In order to solve the above mentioned drawbacks, the inventor of the present invention has proposed an air cleaning system by irradiation of ultraviolet rays (Japanese Patent Application No. 216293/1984). Such a system is effective for a certain application field and utility, but is insufficient if applied to the purification of air containing ultrafine particles and any special field.
SUMMARY OF THE INVENTION
The present invention is a method of cleaning the air by irradiating the air with ultraviolet rays so as to electrically charge the fine particles therein and thereafter remove the charged fine particles from the air, comprising the steps of irradiating a photo-electron discharge member with ultraviolet rays, electrically charging the fine particles by using the photo-electrons generated due to this irradiation, and removing the fine particles charged by the photo-electrons from the air.
Further, in order to execute the above mentioned method, the present invention discloses an apparatus for cleaning the air comprising an ultraviolet ray irradiation portion, photo-electron discharge portions and a charged fine particle-collecting portion on an air flow passage from an air intake port to an air exhaust port.
As a preferred embodiment, there are provided a method of and an apparatus for charging fine particles in the air by photo-electrons generated due to the irradiation of ultraviolet rays to the photo-electron discharge members in an electric field.
As the photo-electron discharge members, there is preferably selected a substance having small photoelectric work function, a compound or alloy thereof to be used solely or as a composite material with two or more types.
Advantages of the invention include the following:
1. When the ultraviolet rays are irradiated to the photoelectron discharge members in an electric field applied with a relatively high voltage by the irradiation of the ultraviolet rays to the photo-electron discharge portions:
(1) The charging of fine particles in the air can be efficiently performed as compared with the conventional electrostatic filter type;
(2) Since the fine particles are efficiently charged, high quality air, i.e., air of high cleaning class can be provided merely by disposing a collector of suitable charged particles such as an electrostatic filter at the trailing stream side;
(3) Since ultrafine particles are collected by electrically charging, a superclean room can be obtained; and
(4) Since in comparison with the conventional electrostatic ultrafine particle collecting type, a high voltage is not necessary, it is safe and costs less to maintain and manage.
2. When sterilization is provided in the ultraviolet rays;
(1) Sterilized clean air is obtained;
(2) It is particularly effective in a field for affecting the influence of the presence of microorganism, like a biotechnologic field; and
(3) The collection of charged particles may not be so restrictive in a biotechnologicl relation, i.e., small leakage is allowed to provide an inexpensive apparatus.
3. It is easy to attain an ultra-high quality air circusmtances, i.e., cleaning class 1, cleaning class 10, which was not attainable in the conventional technique.
The other features and advantages of the present invention will become fully apparent by the following description when read in conjunction with the best mode for practicing the present invention shown in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of the type with a clean bench in a biological clean room, i.e., the type that a part in a working area is highly cleaned.
FIG. 2 is a schematic view showing an embodiment of an ultraviolet ray irradiating portion and a photoelectron discharge portion.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In a clean room 1, rough particles of atmospheric air fed from a conduit 2 are filtered by a prefilter 3, temperature and moisture are regulated by an air conditioner 6 through a fan 5 together with the air removed from an air intake port 4 of the room 1, fine particles are removed from the air by a HEPA filter 7, and the air is then circulated and supplied so as to be maintained in the cleaning class of approx. 10,000.
Aseptic atmospheric air of a high cleaning class (class 10) is held over a work base 13 in a clean bench 11 provided with a fan and a voltage supply unit 8, an ultraviolet ray irradiation portion 9 and a filter 10 in the room 1.
More particularly, in the clean bench 11, the air of the cleaning class of approx. 10,000 in the room 1 is intaken by the fan and the fan of the voltage supply unit 8, the ultraviolet rays are irradiated by the irradiation portion 9 to electrically charge the fine particles in the air and to sterilize microorganisms such as virus, bacteria, yeast or mold, the charged fine particles are then removed by the filter 10 to maintain the air in a high cleaning class above the work base 13.
The ultraviolet ray irradiation portion and the photo-electron discharge portion are, as schematically shown in FIG. 2, mainly formed of a discharge electrode 20, the metal surface 21 of the photo-electron discharge member, and an ultraviolet ray lamp 22. A voltage is loaded from the fan and the voltage supply unit 8 to between the electrode 20 and the metal surface 21, the ultraviolet rays are irradiated by the lamp 22 to the metal surface 21, and the fine particles in the air 50 are efficiently charged by passing the air 50 between the electrode 20 and the metal surface 21.
The distance between the electrode 20 and the metal surface 21 is generally 2 to 20 cm per unit cell according to the shape of the apparatus, and 5 cm in this embodiment.
The material and the construction of the electrode 20 may be those ordinarily used in a charging device. In the embodiment described above, a tungsten wire is used. In FIG. 2, numeral 23 designates a rough filter, and numeral 24 is an electrostatic filter.
In the embodiment in FIG. 2, to form an electric field, the metal surface 21 and the electrode 20 of the photo-electron discharge portion are formed of separate materials. However, the metal surface 21 of the photo-electron discharge material may be used as the discharge electode. In this case, the electrode 20 is omitted from the example in FIG. 2, and the voltage is applied from the fan and the voltage supply unit 8 to the metal surface 21 of the photo-electron discharge member of material.
Then, the metal surface 21 may be any which generates photo-electrons by the irradiation of the ultraviolet rays, which is more preferable if having smaller photo-electric work function. From the point of view of both advantage and economy, any of Ba, Sr, Ca, Y, Gd, La, Ce, Nd, Th, Pr, Be, Zr, Fe, Ni, Zn, Cu, Ag, Pt, Cd, Pb, Al, C, Mg, Au, In, Bi, Nb, Si, Ta, Ti, Sn and P or compounds or alloys of them are preferable, and may be used solely or in combination of two or more of them. As a composite material, a physical composite material like amalgam may be employed.
For example, oxides, borides, and carbides are suitable compounds. The oxides include BaO, SrO, CaO, Y 2 O 6 , Gd 2 O 3 , Nd 2 O 3 , ThO 2 , ZrO 2 , Fe 2 O 3 , ZnO, CuO, Ag 2 O, PtO, PbO, Al 2 O 3 , MgO, In 2 O 3 , BiO, NbO, and BeO; the borides include YB 6 , GdB 6 , LaB 6 , CeB 6 , PrB 6 , and ZrB 2 ; and the carbides include ZrC, TaC, TiC and NbC.
The alloys include brass, bronze, phosphorus bronze, alloys of Ag and Mg (2-20 wt % of Mg), alloys of Cu and Be (1-10 wt % of Be) and alloys of Ba and Al. The alloys of Ag and Mg, Cu and Be and Ba and Al are preferable. Oxides can be obtained by heating only the metal surface in the air, or oxidizing the metal surface with medicine.
Another method involves heating the metal surface before using so as to form an oxide layer on the surface to obtain a stable oxide layer for a long period. As an example of this, the alloy of Mg and Ag is heatead at 300°-400° C. in steam to form a thin oxide film, thereby stabilizing the thin oxide film for a long period.
Shapes of the material which may be used include a plate shape, a brief shape, or a mesh shape in such a manner that the contacting area with the air and the irradiating surface of ultraviolet rays are preferably larger, and the mesh shape is more preferable from this standpoint.
The applied voltage is 0.1 to 10 kV, preferably 0.1 to 5 kV, and more preferably 0.1 to 1 kV, and the voltage depends upon the shape of the apparatus, the electrodes to be used or the material, the construction or the efficiency of the metal.
The types of the ultraviolet rays may be any of generating photo-electrons from the photo-electron discharge material by the irradiation, and preferably have sterilizing action. This may be suitably determined according to the applying field, working content, utility and economy. For example, in the biological field, far ultraviolet rays may be preferably contained from the standpoint of sterilizing action and high efficiency.
Charged fine particles which contain dead organisms are collected by the electrostatic filter 10. The collector of the charged particles may be any type, such as a dust collecting plate (dust collecting electrode) in an ordinary charging device or electrostatic filter type, and the collector itself of steel wool electrode is effective as the structure for forming the electrodes. The electrostatic filter type may be readily handled and effective at the points of performance and the economy. When the filter is used for a predetermined period, it may clog, and a cartridge structure may be employed as required to stably operate by replacing by the detection of the pressure loss for a long period.
The introduction and the removal of implements and products to the work base 13 in the bench 11 can be performed by a movable shutter 12 provided in the bench 11.
As charging type of fine particles in the air, there has been described the type for discharging photo-electrons by irradiating the ultraviolet rays to the photo-electron discharge metal surface in an electric field applied with relatively high voltage. However, fine particles in the air may be charged by irradiating the ultraviolet rays to the photo-electron discharge material without forming an electric field. In this case, in the embodiments in FIGS. 1 and 2, the construction for forming the electric field may be omitted.
The positional relationship of the fan, ultraviolet ray lamp, electric field, and the photo-electron discharge material in the present invention depends upon the type of air cleaning method, scale of the air cleaning method and air flowing method, and are not limited to the particular embodiments.
There are two types of air cleaning methods. One highly cleans part of a working area; the second highly cleans an entire room. The former is generally more economic.
When the present invention is applied to the field of biotechnology, nitrogen plenty air proposed by the inventor of the present invention is effectively employed. (Refer to Japanese Patent Application No. 216293/1984.) | A method of and an apparatus for cleaning the air by irradiating the air with ultraviolet rays to electrically charge the fine particles therein, and thereafter removing the charged fine particles from the air are disclosed. The cleaning method of the air (50) has the following steps: irradiating a photo-electron discharge member (21) with ultraviolet rays (22), electrically charging the above mentioned fine particles by using the photo-electrons generated due to this irradiation, and removing the fine particles charged by the photo-electrons from the air (50) by electrostatic filters (10, 24). The apparatus for practicing the method has an ultraviolet ray irradiation portion (9), photo-electron discharge portions (21) and a charged fine particle-collecting portion (10) on an air flow passage from an air intake port to an air exhaust port. | 1 |
PRIORITY
[0001] This international, non-provisional application claims priority from a provisional application, U.S. Ser. No. 61/382,159, filed Sep. 13, 2010.
BACKGROUND OF THE INVENTION
[0002] Bed bugs are small parasitic insects that feed exclusively on the blood of warm-blooded animals. While they can be found individually, they often congregate once established. They prefer to remain in areas close to hosts, often in or near beds or couches but also in luggage or furniture. They are generally nocturnal and prefer resting in dark crevices. Females usually lay 2-3 eggs per day and most reach an average of 200-500 eggs in their lifespan. Eggs usually hatch after 10 days but may take as long as 28 days before hatching. Some adults have been known to live without feeding for several months or possibly as much as a year, and nymphs, immature bed bugs, can live for up to four months without a meal. Their lifespan under ideal circumstances is about a year. Because of their habits and the fact that humans serving as hosts usually don't feel a bite, a bed bug infestation may go unnoticed for quite some time.
[0003] Bed bugs were nearly eradicated in the 1970s due to the use of DDT, which is now banned in the United States. Within the past decade or so, however, bed bugs have become a prevalent problem for many businesses and individuals. The hospitality industry has faced the biggest challenge. Hotels cannot do anything to prevent their guests from bringing the pests into their facilities, and sanitation has little to do with the establishment of bed bugs. This is a huge problem since guests may sue for damages and may also harm a business's reputation with negative reviews.
[0004] Several techniques for dealing with bed bugs have been developed over the years. A first attempt to eradicate the pests generally involves a thorough cleaning of the infected areas, including washing and drying any fabrics at high temperatures. Since the eggs are so small and generally hidden, this is often ineffective. Another option is to utilize one of the over 300 chemical treatments registered by the EPA for use against bed bugs. Unfortunately, the use of pesticides is not ideal for a number of reasons. First, chemicals harmful to the pests are likely to be harmful to humans or animals who may be exposed to the treatments. Accordingly, places and items treated with pesticides should be removed from access or service until the opportunity for toxic effects have passed. In the alternative, the safest techniques involve placing the pesticide products where humans and animals will not come into contact with the products. Nothing has yet been discovered to attract bed bugs to such products since they are uninterested in anything except blood, and as already mentioned these pests are generally located only in places conveniently near to their potential hosts. It is, thus, unlikely that the pests will, on their own, find and expose themselves to the products. Second, many populations of bed bugs have become resistant to pesticides. Some products and application methods may even make the problem worse by aiding of the development of immunities within the exposed population of pests or by causing the bed bugs to disperse, thereby spreading the infestation. Accordingly, a non-chemical approach is preferable.
[0005] Fortunately, there are non-chemical approaches available. All insects, including bed bugs, have a temperature range within which they can thrive and survive. For bed bugs, development stops at temperatures above approximately 99 degrees Fahrenheit and below approximately 55 degrees Fahrenheit. Adult bed bugs die when temperatures of at least 113 degrees Fahrenheit are maintained for 90 minutes or below 23 degrees Fahrenheit for several days. Instant death occurs for adults at 118 degrees Fahrenheit and 122 degrees Fahrenheit for eggs. Since it is easier to heat items or rooms to these temperatures for the specified times rather than cool them for several days, the use of heated atmospheric air is perhaps the most preferred method for treating bed bugs. This eliminates or minimizes the use of pesticides. This provides a safer environment for anyone exposed to the room or treated items, allows the rooms and items to be immediately accessed upon treatment, and does not provide the opportunity for pesticide resistance. If the treated area or items can be sealed, this provides an additional advantage since the bed bugs cannot escape and spread the infestation.
[0006] U.S. Pat. No. 6,141,901 discloses a technique for treating pests using heated air. The method requires pumping heated outside air into the area to be treated for a period of time. The outside air is heated to at least 200 degrees Fahrenheit and pumped into the area until the temperature inside the area rises to a lethal temperature.
[0007] U.S. Pat. No. 6,588,140 discloses another technique for treating pests using heated air. This method teaches the placement of articles in an enclosure, which is then sealed with a flexible, heat-resistant material. Hot air is then pumped into the enclosure, killing the pests.
[0008] U.S. Pat. No. 6,327,812 also discloses a method for treating pests using heated air within an enclosure. Hot air produced outside the enclosure is pumped into the enclosure. Temperature-sensing probes are installed within the enclosure to ensure that a lethal temperature is reached.
[0009] U.S. Patent Application No. 2010/0071258 discloses yet another system for using heated air to exterminate pests. The system includes two heaters, at least one of which further comprises a fan; several temperature-sensing probes; and a data recorder to receive and record temperature readings from the probes.
BRIEF DESCRIPTION OF THE INVENTION
[0010] The subject invention relates to a system, method, and kit for exterminating pests by thermal treatment of articles that may host bed bugs or other pests. Specifically, the articles to be treated are placed along with specific equipment in a heat chamber. The equipment in the chamber is used to heat the chamber to a temperature known to be lethal to the pests and monitor the temperature in the chamber to ensure the extermination of the pests.
BRIEF DESCRIPTION OF DRAWINGS
[0011] FIG. 1 is an expanded view of the top, side, and end panels of an exemplary embodiment of the heat chamber.
[0012] FIG. 2 shows a hinged panel assembly used to construct the walls of the heat chamber.
[0013] FIG. 3 shows a portion of a hinged panel assembly used to construct the walls of the heat chamber.
[0014] FIG. 4 shows a truss used to support the top panels of the heat chamber.
[0015] FIG. 5 depicts a completely assembled heat chamber.
[0016] FIGS. 6A and 6B depict a disassembled heat chamber. FIG. 6A shows the disassembled heat chamber before it is packed into bags for transport, and FIG. 6B shows the disassembled heat chamber packed into bags.
[0017] FIG. 7 depicts a partially assembled heat chamber with some equipment and articles to be treated.
DESCRIPTION OF THE INVENTION
[0018] The present invention is directed to a system and method for treating articles that are infested or potentially infested with pests. While this system and method is described with respect to the extermination of bed bugs, the system and method may be used to eliminate other insects or microorganisms.
[0019] FIGS. 1-7 show aspects of the system according to an exemplary embodiment. FIG. 1 shows an exemplary embodiment of a complete heat chamber 1 , not including the floor assembly. The chamber 1 consists of a pair of side panel assemblies 10 , 10 ′; a pair of end panel assemblies 20 , 20 ′; and a top panel assembly 30 . As one skilled in the art will discern, the chamber 1 may be of any shape, such as square, triangular with three sides, round, or even pyramidal with a top formed by the intersection of the sides. Each assembly 10 , 10 ′, 20 , 20 ′, 30 is comprised of one or more panel sections. For example in the exemplary embodiment as shown in FIG. 1 , the side panel assembly 10 is comprised of three panel sections 12 , 14 , 16 . As shown in FIG. 2 , the panel sections 12 , 14 , may be hinged at the seam 21 to allow for folding and ease of transportation, and to make solid seams when the panels 12 , 14 , are unfolded. It is contemplated that the sections of each assembly 10 , 10 ′, 20 , 20 ′, 30 would be manufactured of a durable, impermeable, and somewhat flexible material, such as a vinyl fabric. Such material will, when the chamber 1 is assembled such that the assemblies 10 , 10 ′, 20 , 20 ′, 30 form an enclosure, create a radiant barrier.
[0020] Each panel section, as shown in detail with respect to sections 12 , 14 in FIG. 2 , has an edge 13 , 15 . As shown with respect to section 12 , the edge 13 is comprised of two flaps 23 , 25 , which can be opened to reveal an aperture into which an insulating support 27 may be inserted. The insulating support 27 may be comprised of any material suitable for this application, such as a thick rigid foam board like polystyrene, polyisocyanurate, or polyurethane, having a sufficient R-value so that the section 12 with the insulating support 27 inserted may act as a radiant barrier. The benefit of this design is that insulating support 27 may be removed and replaced if it becomes damaged, providing increased convenience and affordability over chambers without this feature. In certain embodiments, the flaps 23 , 25 are further comprised of one or more fastening devices, such as hook and loop fasteners, snaps, zippers, or buttons. As one skilled in the art should discern, the insertion points for the insulating support 27 may be differently configured than as shown.
[0021] As shown in detail in FIG. 2 with respect to sections 12 , 14 , the sections of side and end panel assemblies 10 , 10 ′, 20 , 20 ′ may have flaps 29 , 31 at the bottom edges of the sections 12 , 13 . These flaps 29 , 31 will help to create a seal to more reduce air loss within the chamber 1 . The flaps 29 , 31 may be made of the same material as the panel assemblies 10 , 10 ′, 20 , 20 ′ or may be made of another appropriate materials, such as that used for door sweeps.
[0022] As shown in FIG. 3 with respect to sections 12 , 14 and top panel assembly 30 , there may be fastening devices, such as hook and loop fasteners, snaps, zippers, or buttons, at the edges of the sections 12 , 14 and the top panel assembly 30 to secure the top panel assembly 30 to the sections 12 , 14 . The fastening devices may comprise a first and second mating component, with the first mating component disposed on a top portion of the panels forming the sides of the chamber. The second mating component may be disposed on a flap connected to an outer edge portion of the panels forming the top of the chamber or may be disposed on an outer edge portion of the panels forming the top of the chamber. In the exemplary embodiment shown, top panel assembly may have flaps 32 , 32 ′ along its outer edges. As shown with respect to the flaps 32 , 32 ′, the flaps 32 , 32 ′ may have fastening devices 33 , 33 ′ on the bottom side so that the top panel assembly 30 may be secured to the panels 12 , 14 by folding down the flaps 32 , 32 ′ and attaching the fastening devices 33 , 33 ′ to the fastening devices 35 , 35 ′ at the top portion of the panels 12 , 14 . This attachment provides structural support for the heat chamber 1 as well as providing for decreased air leakage and thus increased effectiveness of the radiant barrier created by the assemblies 10 , 10 ′, 20 , 20 ′, 30 . As shown with respect to the flaps 32 , 32 ′, the flaps 32 , 32 ′ may have fastening devices 34 , 34 ′ on the top side so that the flaps 32 , 32 ′ may be tucked away for storage by attaching the fastening devices 34 , 34 ′ to fastening devices 36 , 36 ′ on the top panel assembly 30 .
[0023] FIG. 4 shows a truss 40 . When the heat chamber 1 is assembled, one or more trusses 40 may be used to prevent the top panel assembly 30 from sagging, allowing for a more airtight seal of the top panel assembly 30 to the side and end panel assemblies 10 , 10 ′, 20 , 20 ′. The exemplary truss 40 is comprised of a bar 42 . The bar 42 has two end clamps 44 , 44 ′, one at each proximal end. In the exemplary embodiment, the end clamps 44 , 44 ′ are fixed and identically situated for such that the surfaces to be clamped will be parallel to each other. In the middle section of the bar 42 in the exemplary embodiment, there are two supports 46 , 46 ′. When used to assemble the heat chamber 1 , the bar 42 stretches the width of the chamber 1 , with supports 46 , 46 ′, supporting the top panel assembly, and end clamps 44 , 44 ′ securing the truss 40 to the chamber 1 by clamping to the top edges of the side panel assemblies 10 , 10 ′.
[0024] FIG. 5 shows the heat chamber 1 completely assembled. The top panel assembly 30 is secured to the side and end panel assemblies 10 , 10 ′, 20 , 20 ′ ( 10 ′ and 20 ′ not shown). As called out with respect to section 12 , a flap 32 attached to the top panel assembly has been folded down and attached to section 12 such that the fastening device 33 (not shown) on the underside of the flap 32 is connected to the fastening device 35 (not shown) at the top portion of the panel 12 . When fully assembled as depicted, the heat chamber 1 is sealed sufficiently for the interior to maintain a temperature lethal to bed bugs.
[0025] FIGS. 6A and 6B depict the heat chamber 1 completely disassembled. In FIG. 6A , each of the assemblies 10 , 10 ′, 20 , 20 ′, 30 has been broken down, folded, and stacked into two piles on top of unassembled carrying cases 100 , 100 ′. As called out with respect to case 100 ′, the case 100 ′ is comprised of several sections 110 , 120 , 130 , 140 , portions of which are edged with fastening devices 112 , 114 , 122 , 132 , 142 . The sections 110 , 120 , 130 , 140 , may be folded and secured with the 112 , 114 , 122 , 132 , 142 , to envelop the assemblies 10 , 10 ′, 20 , 20 ′, 30 . FIG. 6B depicts the assembled carrying cases 100 , 100 ′, which may be equipped with handles 150 , 152 , 154 . These carrying cases 100 , 100 ′ provide an easy way to transport the heat chamber 1 .
[0026] FIG. 7 depicts an assembled but unsealed heat chamber 1 . The assemblies 10 , 10 ′, 20 , 20 ′ rest on a floor assembly 70 , which is sized to match the footprint of the assembled side and end panel assemblies 10 , 10 ′, 20 , 20 ′. The floor assembly 70 may be comprised of any number of heat-reflective materials designed to act as thermal insulation. In an exemplary embodiment, the floor assembly 70 is comprised of rigid insulated foam panels with an aluminum foil backing glued to masonite board. The masonite board prevents items being placed on the assembly 70 from puncturing the foam panels. The inclusion of the floor assembly 70 as part of the heat chamber 1 provides additional support and avoids the possibility of structural damage to the building within which the treatment is being done. The assembly 70 also serves to reflect and contain heat, making easier the maintenance of a particular temperature within the chamber 1 .
[0027] Inside the heat chamber 1 , a user may place one or more heaters 72 , 74 , one or more fans 76 , 78 , 80 , and one or more temperature monitoring devices 82 , 84 , 86 . The heaters 72 , 74 may be of any type, though electric heaters are likely to be more convenient. The fans 76 , 78 , 80 may also be of any type. In the exemplary embodiment, two fans 76 , 78 are box fans and one fan 80 is an oscillating fan. Any number and type of temperature monitoring devices may be used. In the exemplary embodiment, the temperature monitoring devices are three digital thermometers 82 , 84 , 86 , each having the capability of transmitting their temperature readings to a user outside the chamber 1 . This allows for temperature readings to be quickly obtained and monitored in three different areas within the chamber 1 .
[0028] Convection is a major benefit to the inventive system and method in that it facilitates heat transfer to infested items in an efficient manner. To maximize the convection effect, items, such as a mattress 88 and boxspring 90 , may be placed in the heat chamber 1 and stacked in such a manner as to allow for maximum airflow. To increase the convective effect, the fans 76 , 78 , 80 circulate the heat output by the heaters 72 , 74 . In the exemplary embodiment, three digital thermometers 82 , 84 , 86 are placed throughout the chamber 1 —one 82 in the upper portion of the chamber 1 , one 84 in the lower portion, and one 86 within or on the densest item, such as the mattress 88 .
[0029] Once the items are arranged within the chamber 1 , the heaters 72 , 74 and fans 76 , 78 , 80 are turned on. A user may set the fan speed to the lowest setting to minimize cooling. Once all three thermometers 82 , 84 , 86 read at least the desired temperature, a user may turn off the heaters 72 , 74 . The insulation provided by the top, side, and end assemblies 10 , 10 ′, 20 , 20 ′, 30 should be sufficient to maintain the internal temperature at or above the desired temperature for some time. Though adult bed bugs die at temperatures greater than 113 degrees Fahrenheit in 90 minutes and instantly at temperatures greater than 118 degrees Fahrenheit, it may be preferable to obtain a higher temperature to account for any variances in the temperature sensing devices and/or to ensure that the eggs as well as the adult bugs have been killed. For example, the chamber 1 may be heated to at least 120 degrees Fahrenheit and maintained at this level for 60 minutes, which will kill the adult bugs as well as the eggs. After this time, the heat chamber 1 may be disassembled since heat exposure for that length of time will be sufficient to kill the bugs and their eggs.
[0030] While certain specific relationships, materials and other parameters have been detailed in the above description of preferred embodiments, those can be varied, where suitable, with similar results. Other applications, variations, and ramifications of the present invention will be obvious to those skilled in the art upon reading the present disclosure. Those are intended to be included within the scope of this invention as defined in the claims. | Described herein are a system and method for treating bed bugs or other pests within an enclosure. The system comprises at least one heater, at least one fan, at least one temperature monitoring device, and a heat chamber. The method for use comprises sealing at least one heater, at least one fan, at least one temperature monitoring device, and articles for treatment into a heat chamber and heating the chamber to a temperature known to be lethal to the pests for an appropriate length of time. | 0 |
CROSS REFERENCE TO RELATED APPLICATIONS
Applicant claims priority under 35 U.S.C. §119(e) to U.S. provisional application No. 60/152,823 filed Sep. 7, 1999, the disclosure of which is incorporated herein by reference.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
N/A
BACKGROUND OF THE INVENTION
The trend in power generation gas turbine technology for several decades has been to build turbines of increasing size. The application of these large units in combined cycles lead to 500 MW plants (60 Hz) of two 130 MW gas turbines plus a condensing steam turbine with the associated heat recovery steam generators. The permitting and erection time of these plants is much shorter than those of the usual 2×1000 MW coal fired steam plants (let alone the time required to build a nuclear plant). Nevertheless, with respect to gas turbine unit size, governmental action and economic conditions have created a new situation during the last few years. Under the federal PURPA Law, producers of electricity may sell power back to the utility network when a local surplus of power occurs. This possibility, in principle, extends down to unit sizes characteristic of the needs of individual households (15 kW or less), but these units will be disregarded as subjects of the present invention, for two reasons. First, producing such small units economically in large quantities would necessitate large investments into the setting up of large production facilities similar to automobile engines, which is an industry different from the present gas turbine industry. Second, one of the main advantages of the present invention is extremely low NO x emission, but there are no NO x regulations for such small units. This situation removes the main incentive to apply the present invention to household units. Therefore, the present invention is focused on the mid-sized units in the 1-4 MW range. Such units would be of interest to hospitals, shopping centers, military bases, etc., where heat and electricity can be economically generated in “retail” quantities by the consumer itself, the heat energy being a low cost by-product of power generation. Using the backsale provision of PURPA, the small energy producer can pick the most economical combination of heat and power generation, in accordance with his own changing requirements.
In addition to the opportunities created by the backsale provision of the PURPA law, the ongoing deregulation of electric energy prices is expected to create even greater opportunities for small generating units due to the influence of competition in an emerging free market.
SUMMARY OF THE INVENTION
Under the above-described conditions, a competitive, middle range (1-4 MW) gas turbine system is provided that addresses several characteristics. The system achieves low emissions, especially of NO x , due to the residential environment. NO x reductions in the single digits are possible with an appropriate combustor or burner. The system is also highly efficient to be price competitive with the network. The system may also be used with the least expensive fuel, namely coal. Also, the system may reduce or eliminate the most influential contributor to global warming, the emission of CO 2 .
In particular, the system provides an ambient pressure gas-turbine (APG). The system includes a combustor that burns a gaseous, liquid, or solid fuel in air or another working fluid at ambient pressure. A first heat exchanger upstream of the combustor heats the working fluid to the combustor inlet temperature. A turbine downstream from the combustor expands the combustion gases from the combustor. The combustion gases are directed to the first heat exchanger for heat exchange with the working fluid and then to a compressor operative to compress the combustion gases. A second heat exchanger between the first heat exchanger and the compressor further cools the combustion gases to the compressor inlet temperature.
DESCRIPTION OF THE DRAWINGS
The invention will be more fully understood from the following detailed description taken in conjunction with the accompanying drawings, in which:
FIG. 1 illustrates a prior art regenerative gas turbine cycle;
FIG. 2 illustrates the ambient pressure gas turbine combustor system of the present invention;
FIG. 3 illustrates a multiannular swirl burner for liquid fuels for use with the system of the present invention;
FIG. 4 illustrates the ambient pressure gas turbine combustor system of the present invention incorporating flue gas recirculation;
FIG. 5 is a graph of NO x emissions vs. percentage of flue gas recirculated, illustrating the effect of burner flue gas recirculation and steam injection on NO x emission (steam/fuel ratio=0.12 kg/kg, O 2 at exit=3%); and
FIG. 6 illustrated the ambient pressure gas turbine combustor system of the present invention incorporating a coal gas fuel source.
DETAILED DESCRIPTION OF THE INVENTION
A first embodiment of an ambient pressure gas-turbine combustor (APG) system according to the present invention is shown in FIG. 2. A working fluid enters a first heat exchanger 12 (HEX 1 ) at approximately ambient, atmospheric pressure (station 1 ) at a rate of, for example, 8.2 lb/sec. The working fluid is generally air, although pure oxygen or oxygen enriched air may be used, as described further below. The first heat exchanger 12 heats the air to approximately 660° F. The air then enters a combustor 14 (station 2 ). Fuel from a fuel source 16 is supplied to the combustor 14 through, for example, a suitable fuel injector. The hot combustion products from the combustor 14 are directed to a turbine 18 at approximately atmospheric pressure (station 3 ). Upon exiting the turbine, the pressure has been substantially reduced to below atmospheric pressure. The hot combustion products are directed to the first heat exchanger 12 for heating the incoming working fluid (station 4 ).
The combustion products are also directed to a second heat exchanger 20 (station 5 ) to extract further heat to cool the gas to a desired compressor inlet temperature before being directed to a compressor 22 (station 6 ) on a common shaft with the turbine 18 . Because of thermodynamic reasons (cycle efficiency), the compressor inlet temperature must be kept as low as possible, such as 159° F. The extracted heat, however, cannot be completely utilized in preheating the combustion air in the first heat exchanger 12 (HEX 1 ) because the combustor inlet temperature has to be kept at the conventional 660° F. (otherwise the NO x would rapidly increase). Therefore, the second heat exchanger 20 (HEX 2 ) is provided. The exhaust from the second heat exchanger may be mixed with the compressor exhaust and utilized elsewhere in the plant (not shown), or HEX 2 may be a steam generator, feed water heater, space air heater, etc., depending on the local conditions. The compressor exhaust may also be directed to an exhaust stack 24 .
As an example for a 1.1 MW turbine, the temperature and pressure at the various stations are as follows:
Pressure
Temperature
Station
psia
° F.
1
14.7
59
2
14.3
660
3
13.8
2200
4
1.3
1034
5
1.2
440
6
1.2
159
7
14.7
860
For comparison, a conventional, regenerative cycle is also shown in FIG. 1 . The example is based on a 1.1 MW (electrical) turbine, such as that described in “TG 15 Alternative Fuels Combustor Development,” G. Vermes, Textron-Lycoming Report MO 071390GV1, Jul. 17, 1990. In the conventional cycle, the working fluid is compressed in the compressor, thereby raising its pressure to the operating pressure of the combustor, for example, 12 atm in the 1.1 MW turbine example. As an example for a prior art 1.1 MW turbine, the temperature and pressure at the various states are as follows:
Pressure
Temperature
Station
psia
° F.
1
14.7
59
2
20.0
750
3
19.5
930
4
19.0
2080
5
16.0
1050
6
14.7
900
As is apparent by reference to the above discussion and FIG. 2, the usual sequence of the machinery components of the gas turbine cycle is altered to accommodate the ambient pressure combustor in the present invention. Referring FIG. 2, the working fluid enters the expander first (station 3 ) and the compressor second (station 6 ). In this way, the combustion process takes place at approximately ambient pressure as opposed to the conventional gas turbine (see FIG. 1 ), where the combustor operates at 12 atm (in the example chosen). Other combustor parameters being equal, the reduced pressure results in an approximately (12) ½ =3.46 times reduction of the thermal NO x output of the gas turbine.
A low-NO x burner that is suitable for use in the cycle of the present invention is, for example, the Multi-Annular Swirl Burner (MASB) that has been described in “Low NO x and Fuel Flexible Gas Turbine Combustors,” H. G. Lew et al., Journal of Eng. for Power, vol. 104, April 1982. See also U.S. Pat. No. 4,845,940. This burner produced 80-90 ppm NO x on diesel fuel (DF-2) under APG conditions except for the pressure. Using natural gas as the fuel and at 1 atm pressure, this NO x level would be:
0.55(3.46) −1 85=13.5 ppm(v),
thus satisfying the low NO x criterion. As discussed further below, this burner may also be modified to achieve single digit NO x levels.
The small size of the 1 MW machine would result in blade paths of small dimensions for a conventional turbine. Such small dimensions have a deleterious effect on component efficiency. The conventional cycle used as a basis for comparison has only 84% polytropic (stage) compression efficiency (on average; the last stage must be made centrifugal), resulting in 78% adiabatic efficiency for the compression stage. The turbine (expander) overall efficiency is 87%. In the APG of the present invention, the 10-12 times larger specific volume results in dimensions that are approximately three times larger. This larger machinery size makes it possible to count on better adiabatic efficiency; 94% and 89% were assumed for the turbine (expander) and the compressor, respectively.
The low pressure level of the APG also has an important consequence on the mechanical design of the component machinery. Casings of conventional turbines and compressors have to be designed to withstand a 10-12 atm pressure differential, whereas the APG machinery is designed for a 1 atm pressure differential. Considering that failure in the conventional machine results in an explosion whereas failure in the APG machinery causes an implosion, the reduced pressure and the reduced risk in the APG should result in physically larger but less material-sensitive design.
An important additional inherent advantage of the APG relates to blade cooling. In the conventional turbine, the cooling air is available at the compressor exit temperature (in the cited example, this is 670° F). The amount of cooling air depends on the temperature difference between the desired metal temperature, about 1500° F. and the 670° F. air temperature i.e., 830° F. In the APG turbine, the cooling air is at 60° F., resulting in 1500° F.−60° F.=1440° F. temperature difference, thereby reducing significantly the necessary cooling air flow.
It should be pointed out, to the best of the inventors' knowledge, a 13 ppm NO x level could be achieved so far only with combustors that have unconventional features, such as careful premix, catalytic surfaces, complicated controls, etc. For a small, unattended turbine in a prior art cycle, these features present much greater disadvantages than for large plants. In contrast, the Multi-Annular Swirl Burner (MASB) has none of these drawbacks. Rather, control of the turbine is completely conventional; the diffusion flame and the aerodynamic features of the MASB have been shown to provide excellent stability and an unusually large turn-down ratio; and the availability of practically 100% of the airflow for wall cooling purposes provides for a simple wall structure resulting in low manufacturing costs, etc.
In a further embodiment of the invention, a combustor is provided capable of achieving single-digit NO x levels. The recent (second half of the 1990s) regulatory trend indicates that so-called “single digit” NO x (≦9 ppm(v)) will become a necessity for small (<10 MW) gas turbines used for the generation of electricity in residential areas. Prior art gas turbines available on the market offer NO x levels of 15-20 ppm, using premixed gas and air, or catalytic burners. Both types of burners have difficulties of operation (e.g. turn-down, necessity of pilot burner, danger of flash-back). To restrict the NO x reliably to the single digit level, exhaust cleanup systems are applied which use ammonia to break up the NO x , resulting in additional costs of operation (besides other drawbacks). If the MASB could be improved to have a NO x level of 9 ppm(v) instead of 13 ppm(v), all the above cited difficulties could be avoided.
The multi-annular swirl burner 30 (MASB) mentioned above is shown in FIG. 3 . The figure shows a version with a rich-quench-lean design and a central fuel injector 32 surrounded by annuli through which the working fluid enters. In this design, air flow from the first two annuli 34 , 36 establishes a fuel rich zone. Air flow from the third annulus 38 quenches the high temperature combustion gases of the first two annuli. The unburned fuel completes the combustion with the air of the fourth and fifth annuli 40 , 42 in a fuel lean zone, i.e., relatively low flame temperature reaction mode. Theoretically, such an arrangement should result in single digit NO x (using oil fuel) from the first two annuli, no NO x from the third annulus and negligible NO x from the fourth annulus. Thus, the 80-90 ppm(v) NO x achieved using diesel fuel, mentioned above, though only about 50% of the NO x level from a conventional turbine burner, was much higher than could have been expected.
Analysis of the quoted test results concluded that the rich and the lean burner sections performed as expected: the excess NO x came from the quench section. While the quench flow from the third annulus started to reduce the temperature of the exhaust from the rich section, combustion reactions were triggered by the quench air at stoichiometric temperatures. By the time the mixing process in the quench section established the low temperature lean region necessary to conclude the combustion reactions, there was a 75-80 ppm(v) NO x created during the quench process. It follows that increasing the efficiency of the mixing process in the quench section will reduce the NO x production there, though it may not eliminate it completely.
Projecting the above conclusions (obtained from the analysis of the oil burning MASB results) to the proposed 13.5 ppm(v) NO x atmospheric gas burner case, i.e., reduction of the quench NO x by, say, one-third, the APG turbine system with the improved MASB would obtain single-digital NO x .
During the research program mentioned here, an experimental rich-quench-lean burner was also investigated (not a MASB) where the three sections had independent air supplies. This burner had similar NO x level as the MASB (about 70 ppm(v)). It could be shown experimentally that by changing the quench airflow, reduced residence time in the quench section (i.e., reduced time available for combustion reactions to start there) indeed reduced the NO x emission from the burner. It follows that similar results can be expected from the rich-quench-lean MASB by improving the mixing process in the third annulus.
The aerodynamic design of the MASB discussed here is such that the subsequent annuli (starting from the inside) have decreasing amounts of swirl, set by vanes 44 , 46 , 48 , 50 , 52 in the annuli. The innermost annulus has 60° vanes; the outermost annulus has 20° vanes. All the annuli swirl in the same direction, for example, clockwise. This arrangement provided a so-called “free vortex” arrangement, resulting in a minimum amount of pressure drop across the burner: about 1-2% of the total pressure in the combustion chamber. As the combustor pressure drop in a conventional, diffusion flame gas turbine burner is on the order of 3.5%, a MASB in an APG gas turbine system can afford an additional 1-2% pressure drop without hurting the cycle efficiency, if the increased pressure drop can be put to good use.
In the present invention, it is proposed that the MASB be modified such that the third annulus 38 should have its swirl in an opposite sense to the second and the fourth annulus, for example, counterclockwise. This arrangement would do away with the “free vortex” concept, resulting in a higher pressure drop. A single digit NO x level would, however, be an adequate compensation.
A still further embodiment of the invention incorporates flue gas recirculation to further reduce NO x levels, illustrated in FIG. 4 . Flue gas recirculation through piping 60 from the compressor outlet to the combustor is possible because the combustor operates at near atmospheric pressure. The parameters of the flue gas recirculated from the exhaust of the compressor are 860° F. and 14.7 psi with an approximate O 2 concentration of 16%. By admixing a fraction of the flue gas with the combustion air, the oxygen concentration of the latter becomes depleted, which is instrumental in reducing further the NO x formed during combustion. The effect of flue gas recirculation upon NO x emission from an atmospheric pressure burner of natural gas and air is shown in FIG. 5 . (See “Low NO x Emission from Radially Stratified Natural Gas-Air Turbulent Diffusion Flames,” M. A. Toqan et al., 24 th Symposium (International) on Combustion, The Combustion Institute, Pittsburgh, Pa., 1992.) The fraction of the flue gas recirculated is limited by flame stability considerations but is in the range of 30%.
Due to the slightly higher pressure of the flue gas compared to that of the preheated air entering the combustor the two fluids can be conveniently mixed through the entrainment of the air by flue gas jet(s). Alternatively, the MASB design permits the admission of the recirculated flue gas through one of the annuli at some radial distance from the fuel jet to reduce any detrimental effect on flame stability.
The combination of flue gas recirculation (FGR) with the enrichment of the oxygen content in the O 2 /N 2 /CO 2 oxidizing mixture or even using an O 2 /CO 2 oxidizer, opens new vistas to the APG. In addition to the enhanced cycle efficiency and extremely low NO x level explained above, the enrichment of the O 2 content has the side effect of an increased CO 2 concentration in the exhaust. It was recently shown that increased CO 2 content improves the economics of CO 2 sequestration, which, in turn, mitigates global warming. See “Enriched Oxygen Fired Combustion,” Kelly V. Thambimuthu and Eric Croiset, Report, Natural Resources Canada, 1 Haanel Dr., Nepean, Ontario K1A 1M1, Canada.
As further explanation, the rich-quench-lean sequencing of the combustion process is a known method to reduce NO x emission from combustion turbines. This method is based on the notion that in high temperature, fuel-rich combustion, all nitrogen compounds, NO x , N 2 O, cyanogens, amines, and heterocyclic nitrogen compounds, may be converted to molecular nitrogen, N 2 . N 2 is innocuous for NO x formation. Following the fuel-rich zone, however, more oxidant (air) has to be injected to bring the combustion process to completion and also to reduce the temperature of the combustion products to a level acceptable to the structural elements of the gas turbine, say 1623 K. The quench stage serves for the fast reduction of the gas temperature to below, say 1800 K, reducing thereby NO x formation rates to a negligible level. In this combustion stage, there is a race between the rapid cooling of the products of the fuel rich stage, and the reaction between molecular nitrogen and atomic oxygen to form NO x . In the conventional case, the quenching medium is air and the high O 2 concentration in the air makes it more difficult to avoid the formation of NO x during the quench process. Because of the availability of O 2 deficient flue gas, however, the above-mentioned race can be tilted in favor of the cooling by using recirculated flue gas as the quenching medium. The fast admixing of the relatively cold, say 673 K, flue gas will result in the rapid cooling of the combustion products by dilution, while NO x formation is suppressed owing to the O 2 deficiency. Completion of the combustion process is then achieved by the injection of more air downstream of the quench stage. In this, the lean stage, the fuel burnout is increased to above 99.9% at temperatures and O 2 concentrations close to the values at the combustor exit.
An additional perspective of the combination of the APG and the use of oxygen relates to coal as a gas turbine fuel. When using so called “clean fuels” (natural gas, No. 2 distillate), no flue gas cleanup is envisaged. For coal, however, hot gas cleanup is necessary before the combustion products enter the blade path of the expander. In this case, the coal undergoes gasification in an O 2 blown gasifier 72 , followed by cleaning of the product gas in a cleaner 74 . The syngas so produced is then burned with more of the O 2 /CO 2 mixture in the combustor. Temperature control of the combustor would be as before, by flue gas recirculation.
The arrangement of the turbine components of the present invention thus makes possible flue gas recirculation at ambient pressure. Flue gas recirculation makes application of the system to a low emission gas turbine cycle favorable for CO 2 sequestration.
Cleaning of the hot gases has to be very thorough due to the sensitivity of the aerodynamic surfaces of the turbine blades to the erosive effect of solid particles at the high velocities prevailing in the blade passages. In fact, repeated attempts to introduce into industrial practice the direct coal fired gas turbine proved unsuccessful during the last fifty years, due to the lack of acceptable and affordable cleaning equipment at high temperature and high pressure. Transferring the cleaning process from high pressure to ambient, as in the present invention, may make the existing cleaning technology practical.
The invention is not to be limited by what has been particularly shown and described, except as indicated by the appended claims. | An ambient pressure gas turbine system is provided for mid-range power plants (for example, 1-4 MW) while achieving low NO x emission levels. The system includes a combustor that burns a hydrocarbon fuel at ambient pressure. A first heat exchanger upstream of the combustor heats the working fluid. A turbine downstream from the combustor expands combustion gases. The combustion gases are directed to the first heat exchanger for heat exchange with the working fluid and then to a compressor operative to compress the combustion gases. A second heat exchanger between the first heat exchanger and the compressor further cools the combustion gases to the compressor inlet temperature. | 5 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a division of patent application Ser. No. 09/431,888, and claims the benefit of U.S. Provisional Application No. 60/106,689, filed Nov. 2, 1998; and U.S. Provisional Application No. 60/106,800, filed Nov. 3, 1998.
FIELD OF THE INVENTION
[0002] This invention relates to viral vascular endothelial growth factor-like proteins which binds and activates the mammalian VEGF receptor-2 to induce vascular permeability of endothelial cells, and in particular to pharmaceutical and diagnostic compositions and methods utilizing or derived from the factor.
BACKGROUND OF THE INVENTION
[0003] In the developing embryo, the primary vascular network is established by in situ differentiation of mesodermal cells in a process called vasculogenesis. It is believed that all subsequent processes involving the generation of new vessels in the embryo and neovascularization in adults, are governed by the sprouting or splitting of new capillaries from the pre-existing vasculature in a process called angiogenesis (Pepper et al., Enzyme & Protein, 1996 49 138-162; Breier et al., Dev. Dyn. 1995 204 228-239; Risau, Nature, 1997 386 671-674). Angiogenesis is not only involved in embryonic development and normal tissue growth, repair, and regeneration, but is also involved in the female reproductive cycle, establishment and maintenance of pregnancy, and in repair of wounds and fractures. In addition to angiogenesis which takes place in the normal individual, angiogenic events are involved in a number of pathological processes, notably tumor growth and metastasis, and other conditions in which blood vessel proliferation, especially of the microvascular system, is increased, such as diabetic retinopathy, psoriasis and arthropathies. Inhibition of angiogenesis is useful in preventing or alleviating these pathological processes.
[0004] On the other hand, promotion of angiogenesis is desirable in situations where vascularization is to be established or extended, for example after tissue or organ transplantation, or to stimulate establishment of collateral circulation in tissue infarction or arterial stenosis, such as in coronary heart disease and thromboangitis obliterans.
[0005] The angiogenic process is highly complex and involves the maintenance of the endothelial cells in the cell cycle, degradation of the extracellular matrix, migration and invasion of the surrounding tissue and finally, tube formation. The molecular mechanisms underlying the complex angiogenic processes are far from being understood.
[0006] Because of the crucial role of angiogenesis in so many physiological and pathological processes, factors involved in the control of angiogenesis have been intensively investigated. A number of growth factors have been shown to be involved in the regulation of angiogenesis; these include fibroblast growth factors (FGFs), platelet-derived growth factor (PDGF), transforming growth factor alpha (TGFα), and hepatocyte growth factor (HGF). See for example Folkman et al., J. Biol. Chem., 1992 267 10931-10934 for a review.
[0007] It has been suggested that a particular family of endothelial cell-specific growth factors, the vascular endothelial growth factors (VEGFs), and their corresponding receptors is primarily responsible for stimulation of endothelial cell growth and differentiation, and for certain functions of the differentiated cells. These factors are members of the PDGF family, and appear to act primarily via endothelial receptor tyrosine kinases (RTKs).
[0008] Nine different proteins have been identified in the PDGF family, namely two PDGFs (A and B), VEGF and six members that are closely related to VEGF. The six members closely related to VEGF are: VEGF-B, described in International Patent Application PCT/US96/02957 (WO 96/26736) and in U.S. Pat. Nos. 5,840,693 and 5,607,918 by Ludwig Institute for Cancer Research and The University of Helsinki; VEGF-C, described in Joukov et al., EMBO J., 1996 15 290-298 and Lee et al., Proc. Natl. Acad. Sci. USA, 1996 93 1988-1992; VEGF-D, described in International Patent Application No. PCT/US97/14696 (WO 98/07832), and Achen et al., Proc. Natl. Acad. Sci. USA, 1998 95 548-553; the placenta growth factor (PlGF), described in Maglione et al., Proc. Natl. Acad. Sci. USA, 1991 88 9267-9271; VEGF2, described in International Patent Application No. PCT/US94/05291 (WO 95/24473) by Human Genome Sciences, Inc; and VEGF3, described in International Patent Application No. PCT/US95/07283 (WO 96/39421) by Human Genome Sciences, Inc. Each VEGF family member has between 30% and 45% amino acid sequence identity with VEGF. The VEGF family members share a VEGF homology domain which contains the six cysteine residues which form the cysteine knot motif. Functional characteristics of the VEGF family include varying degrees of mitogenicity for endothelial cells, induction of vascular permeability and angiogenic and lymphangiogenic properties.
[0009] Vascular endothelial growth factor (VEGF) is a homodimeric glycoprotein that has been isolated from several sources. VEGF shows highly specific mitogenic activity for endothelial cells. VEGF has important regulatory functions in the formation of new blood vessels during embryonic vasculogenesis and in angiogenesis during adult life (Carmeliet et al., Nature, 1996 380 435-439; Ferrara et al., Nature, 1996 380 439-442; reviewed in Ferrara and Davis-Smyth, Endocrine Rev., 1997 18 425). The significance of the role played by VEGF has been demonstrated in studies showing that inactivation of a single VEGF allele results in embryonic lethality due to failed development of the vasculature (Carmeliet et al., Nature, 1996 380 435-439; Ferrara et al., Nature, 1996 380 439-442). In addition VEGF has strong chemoattractant activity towards monocytes, can induce the plasminogen activator and the plasminogen activator inhibitor in endothelial cells, and can also induce microvascular permeability. Because of the latter activity, it is sometimes referred to as vascular permeability factor (VPF). The isolation and properties of VEGF have been reviewed; see Ferrara et al., J. Cellular Biochem., 1991 47 211-218 and Connolly, J. Cellular Biochem., 1991 47 219-223. Alterative mRNA splicing of a single VEGF gene gives rise to five isoforms of VEGF.
[0010] VEGF-B has similar angiogenic and other properties to those of VEGF, but is distributed and expressed in tissues differently from VEGF. In particular, VEGF-B is very strongly expressed in heart, and only weakly in lung, whereas the reverse is the case for VEGF. This suggests that VEGF and VEGF-B, despite the fact that they are co-expressed in many tissues, may have functional differences.
[0011] VEGF-B was isolated using a yeast co-hybrid interaction trap screening technique by screening for cellular proteins which might interact with cellular resinoid acid-binding protein type I (CRABP-I). Its isolation and characteristics are described in detail in PCT/US96/02957 and in Olofsson et al., Proc. Natl. Acad. Sci. USA, 1996 93 2576-2581.
[0012] VEGF-C was isolated from conditioned media of the PC-3 prostate adenocarcinoma cell line (CRL1435) by screening for ability of the medium to produce tyrosine phosphorylation of the endothelial cell-specific receptor tyrosine kinase VEGFR-3 (Flt4), using cells transfected to express VEGFR-3. VEGF-C was purified using affinity chromatography with recombinant VEGFR-3, and was cloned from a PC-3 cDNA library. Its isolation and characteristics are described in detail in Joukov et al., EMBO J., 1996 15 290-298.
[0013] VEGF-D was isolated from a human breast cDNA library, commercially available from Clontech, by screening with an expressed sequence tag obtained from a human cDNA library designated “Soares Breast 3NbHBst” as a hybridization probe (Achen et al., Proc. Natl. Acad. Sci. USA, 1998 95 548-553). Its isolation and characteristics are described in detail in International Patent Application No. PCT/US97/14696 (WO98/07832).
[0014] The VEGF-D gene is broadly expressed in the adult human, but is certainly not ubiquitously expressed. VEGF-D is strongly expressed in heart, lung and skeletal muscle. Intermediate levels of VEGF-D are expressed in spleen, ovary, small intestine and colon, and a lower expression occurs in kidney, pancreas, thymus, prostate and testis. No VEGF-D mRNA was detected in RNA from brain, placenta, liver or peripheral blood leukocytes.
[0015] PlGF was isolated from a term placenta cDNA library. Its isolation and characteristics are described in detail in Maglione et al., Proc. Natl. Acad. Sci. USA, 1991 88 9267-9271. Presently its biological function is not well understood.
[0016] VEGF2 was isolated from a highly tumorgenic, oestrogen-independent human breast cancer cell line. While this molecule is stated to have about 22% homology to PDGF and 30% homology to VEGF, the method of isolation of the gene encoding VEGF2 is unclear, and no characterization of the biological activity is disclosed.
[0017] VEGF3 was isolated from a cDNA library derived from colon tissue. VEGF3 is stated to have about 36% identity and 66% similarity to VEGF. The method of isolation of the gene encoding VEGF3 is unclear and no characterization of the biological activity is disclosed.
[0018] Similarity between two proteins is determined by comparing the amino acid sequence and conserved amino acid substitutions of one of the proteins to the sequence of the second protein, whereas identity is determined without including the conserved amino acid substitutions.
[0019] PDGF/VEGF family members act primarily by binding to receptor tyrosine kinases. Five endothelial cell-specific receptor tyrosine kinases have been identified, namely VEGFR-1 (Flt-1), VEGFR-2 (KDR/Flk-1), VEGFR-3 (Flt4), Tie and Tek/Tie-2. All of these have the intrinsic tyrosine kinase activity which is necessary for signal transduction. The essential, specific role in vasculogenesis and angiogenesis of VEGFR-1, VEGFR-2, VEGFR-3, Tie and Tek/Tie-2 has been demonstrated by targeted mutations inactivating these receptors in mouse embryos.
[0020] The only receptor tyrosine kinases known to bind VEGFs are VEGFR-1, VEGFR-2 and VEGFR-3. VEGFR-1 and VEGFR-2 bind VEGF with high affinity, and VEGFR-1 also binds VEGF-B and PlGF. VEGF-C has been shown to be the ligand for VEGFR-3, and it also activates VEGFR-2 (Joukov et al., The EMBO Journal, 1996 15 290-298). VEGF-D binds to both VEGFR-2 and VEGFR-3. A ligand for Tek/Tie-2 has been described in International Patent Application No. PCT/US95/12935 (WO 96/11269) by Regeneron Pharmaceuticals, Inc. The ligand for Tie has not yet been identified.
[0021] Recently, a novel 130-135 kDa VEGF isoform specific receptor has been purified and cloned (Soker et al., Cell, 1998 92 735-745). The VEGF receptor was found to specifically bind the VEGF 165 isoform via the exon 7 encoded sequence, which shows weak affinity for heparin (Soker et al., Cell, 1998 92 735-745). Surprisingly, the receptor was shown to be identical to human neuropilin-1 (NP-1), a receptor involved in early stage neuromorphogenesis. PlGF-2 also appears to interact with NP-1 (Migdal et al., J. Biol. Chem., 1998 273 22272-22278).
[0022] VEGFR-1, VEGFR-2 and VEGFR-3 are expressed differently by endothelial cells. Both VEGFR-1 and VEGFR-2 are expressed in blood vessel endothelia (Oelrichs et al., Oncogene, 1992 8 11-18; Kaipainen et al., J. Exp. Med., 1993 178 2077-2088; Dumont et al., Dev. Dyn., 1995 203 80-92; Fong et al., Dev. Dyn., 1996 207 1-10) and VEGFR-3 is mostly expressed in the lymphatic endothelium of adult tissues (Kaipainen et al., Proc. Natl. Acad. Sci. USA, 1995 9 3566-3570). VEGFR-3 is also expressed in the blood vasculature surrounding tumors.
[0023] Disruption of the VEGFR genes results in aberrant development of the vasculature leading to embryonic lethality around midgestation. Analysis of embryos carrying a completely inactivated VEGFR-1 gene suggests that this receptor is required for functional organization of the endothelium (Fong et al., Nature, 1995 376 66-70). However, deletion of the intracellular tyrosine kinase domain of VEGFR-1 generates viable mice with a normal vasculature (Hiratsuka et al., Proc. Natl. Acad. Sci. USA 1998 95 9349-9354). The reasons underlying these differences remain to be explained but suggest that receptor signalling via the tyrosine kinase is not required for the proper function of VEGFR-1. Analysis of homozygous mice with inactivated alleles of VEGFR-2 suggests that this receptor is required for endothelial cell proliferation, hematopoesis and vasculogenesis (Shalaby et al., Nature, 1995 376 62-66; Shalaby et al., Cell, 1997 89 981-990). Inactivation of VEGFR-3 results in cardiovascular failure due to abnormal organization of the large vessels (Dumont et al. Science, 1998 282 946-949).
[0024] Although VEGFR-1 is mainly expressed in endothelial cells during development, it can also be found in hematopoetic precursor cells during early stages of embryogenesis (Fong et al., Nature, 1995 376 66-70). In adults, monocytes and macrophages also express this receptor (Barleon et al., Blood, 1996 87 3336-3343). In embryos, VEGFR-1 is expressed by most, if not all, vessels (Breier et al., Dev. Dyn., 1995 204 228-239; Fong et al., Dev. Dyn., 1996 207 1-10).
[0025] The receptor VEGFR-3 is widely expressed on endothelial cells during early embryonic development but as embryogenesis proceeds becomes restricted to venous endothelium and then to the lymphatic endothelium (Kaipainen et al., Cancer Res., 1994 54 6571-6577; Kaipainen et al., Proc. Natl. Acad. Sci. USA, 1995 92 3566-3570). VEGFR-3 is expressed on lymphatic endothelial cells in adult tissues. This receptor is essential for vascular development during embryogenesis. Targeted inactivation of both copies of the VEGFR-3 gene in mice resulted in defective blood vessel formation characterized by abnormally organized large vessels with defective lumens, leading to fluid accumulation in the pericardial cavity and cardiovascular failure at post-coital day 9.5. On the basis of these findings it has been proposed that VEGFR-3 is required for the maturation of primary vascular networks into larger blood vessels. However, the role of VEGFR-3 in the development of the lymphatic vasculature could not be studied in these mice because the embryos died before the lymphatic system emerged. Nevertheless it is assumed that VEGFR-3 plays a role in development of the lymphatic vasculature and lymphangiogenesis given its specific expression in lymphatic endothelial cells during embryogenesis and adult life. This is supported by the finding that ectopic expression of VEGF-C, a ligand for VEGFR-3, in the skin of transgenic mice, resulted in lymphatic endothelial cell proliferation and vessel enlargement in the dermis. Furthermore this suggests that VEGF-C may have a primary function in lymphatic endothelium, and a secondary function in angiogenesis and permeability regulation which is shared with VEGF (Joukov et al., EMBO J., 1996 15 290-298).
[0026] Some inhibitors of the VEGF/VEGF-receptor system have been shown to prevent tumor growth via an anti-angiogenic mechanism; see Kim et al., Nature, 1993 362 841-844 and Saleh et al., Cancer Res., 1996 56 393-401.
[0027] In addition, VEGF-like proteins have been identified which are encoded by four different strains of the orf virus. This is the first virus reported to encode a VEGF-like protein. The first two strains are NZ2 and NZ7, and are described in Lyttle et al., J. Virol., 1994 68 84-92. A third is D1701 and is described in Meyer et al., The EMBO Journal, 1999 18 363-374. The fourth strain is NZ10 and is described herein. These proteins show amino acid sequence similarity to VEGF and to each other.
[0028] The orf virus is a type of species of the parapoxvirus genus which causes a highly contagious pustular dermatitis in sheep and goats and is readily transmittable to humans. The pustular dermatitis induced by orf virus infection is characterized by dilation of blood vessels, swelling of the local area and marked proliferation of endothelial cells lining the blood vessels. These features are seen in all species infected by orf and can result in the formation of a tumor-like growth or nodule due to viral replication in epidermal cells. Generally orf virus infections resolve in a few weeks but severe infections that fail to resolve without surgical intervention are seen in immune impaired individuals. The finding that the orf virus strains NZ2 and NZ7 encode molecules with VEGF-like sequences raises the important question of whether these proteins are capable of binding to mammalian VEGF receptors and inducing characteristic VEGF-like effects such as mitogenesis of endothelial cells and vascular permeability.
SUMMARY OF THE INVENTION
[0029] The invention is based on the discovery that a viral VEGF-like protein from the orf virus strains NZ2 (herein after referred to as ORFV2-VEGF or NZ2)and NZ10 are capable of binding to the extracellular domain of the VEGF receptor-2 to form bioactive complexes which mediate useful cellular responses and/or antagonize undesired biological activities. In addition, ORFV2-VEGF is capable of binding NP1. The invention generally provides for methods which stimulate or inhibit these biological activities, methods for therapeutic applications and finding antagonists of ORFV2-VEGF or NZ10.
[0030] According to a first aspect, the invention provides an isolated and purified nucleic acid molecule which comprises a polynucleotide sequence having at least 85% identity, more preferably at least 90%, and most preferably at least 95% identity to at least the sequence set out in FIG. 10 (SEQ ID NO:10) and that encodes a novel polypeptide, designated ORFV10-VEGF (hereinafter NZ10), which is structurally homologous to VEGF and NZ2. This aspect of the invention also encompasses DNA molecules having a sequence such that they hybridize under stringent conditions with at least nucleotides of the sequence set out in FIG. 10 (SEQ ID NO:10) or fragments thereof.
[0031] According to a second aspect, the polypeptide of the invention has the ability to stimulate proliferation of endothelial cells and comprises a sequence of amino acids substantially corresponding to the amino acid sequence set out in FIG. 11 (SEQ ID NO:11), or a fragment or analog thereof which has the ability to stimulate one or more of endothelial cell proliferation, differentiation, migration or survival. Preferably the polypeptides have at least 85% identity, more preferably at least 90%, and most preferably at least 95% identity to the amino acid sequence of FIG. 11 (SEQ ID NO11), or a fragment or analog thereof having the biological activity of NZ10.
[0032] According to another aspect, the invention provides for a method for stimulating one or more of endothelial cell proliferation, differentiation, migration or survival by exposing them to ORFV2-VEGF or NZ10 or a fragment or analog thereof which has the ability.
[0033] According to a further aspect, the invention provides a method for activation of VEGF receptor-2 which comprises the step of exposing cells bearing said receptor to an effective receptor activating dose of ORFV2-VEGF or NZ10 or a fragment or analog thereof which has the ability.
[0034] Since both ORFV2-VEGF and NZ10 specifically activate the VEGF receptor-2, ORFV2-VEGF can be used to stimulate endothelial cell proliferation in a situation where VEGF receptor 1 is not activated. Accordingly, the invention provides for a method for specific activation of VEGF receptor 2 and VEGF receptor 1 is not activated.
[0035] These abilities are referred to herein as “biological activities of ORFV2-VEGF or NZ10” and can readily be tested by methods known in the art, such as the mitogenic assay described in Example 5. In particular, ORFV2-VEGF and NZ10 have the ability to stimulate endothelial cell proliferation or differentiation, including, but not limited to, proliferation or differentiation of vascular endothelial cells and/or lymphatic endothelial cells.
[0036] More preferably ORFV2-VEGF has the amino acid sequence set out in FIG. 9 (SEQ ID NO:2), while NZ10 has the amino acid sequence set out in FIG. 10 (SEQ ID NO:11).
[0037] In another preferred aspect, the invention provides a polypeptides possessing the characteristic amino acid sequence:
[0038] Pro-Xaa-Cys-Xaa-Xaa-Xaa-Xaa-Arg-Cys-Xaa-Gly-Cys-Cys (SEQ ID NOs:9 and 11), which is characteristic of members of the PDGFIVEGF family of growth factors.
[0039] Polypeptides comprising conservative substitutions, insertions, or deletions, but which still retain the biological activity of ORFV2-VEGF or NZ10, are clearly to be understood to be within the scope of the invention. Persons skilled in the art will be well aware of methods which can readily be used to generate such polypeptides, for example the use of site-directed mutagenesis, or specific enzymatic cleavage and ligation. The skilled person will also be aware that peptidomimetic compounds or compounds in which one or more amino acid residues are replaced by a non-naturally occurring amino acid or an amino acid analogue may retain the required aspects of the biological activity of ORFV2-VEGF. Such compounds can readily be made and tested by methods known in the art, and are also within the scope of the invention.
[0040] In addition, variant forms of the ORFV2-VEGF or NZ10 polypeptide which result naturally-occurring allelic variants of the nucleic acid sequence encoding ORFV2-VEGF or ORFV10-VEGF are encompassed within the scope of the invention. Allelic variants are well known in the art, and represent alternative forms or a nucleic acid sequence which comprise substitution, deletion or addition of one or more nucleotides, but which do not result in any substantial functional alteration of the encoded polypeptide.
[0041] As used herein, the term “ORFV2-VEGF” collectively refers to the polypeptide having the amino acid sequence set forth in FIG. 9 (SEQ ID NO:2) and fragments or analogues thereof and other variants, for example, from natural isolates of the orf virus which have the biological activity of ORFV2-VEGF as herein defined. Those skilled in the art will recognize that there is considerable latitude in amino acid sequence charges which can occur naturally or be engineered without affecting biological activity of the polypeptide. It is preferred that the variant polypeptides be at least 80%, more preferably be at least 90%, and most preferably at least 95% identical to the amino acid sequence of FIG. 9 (SEQ ID NO:2). Percent sequence identity is determined by conventional methods. See, for example, Altschul et al, Bull. Math. Bio., 1986 48 603-616 and Henikoff and Henikoff, Proc. Natl. Acad. Sci. USA, 1992 89 10915-10919.
[0042] As used herein, the term “NZ10” collectively refers to the polypeptide having the amino acid sequence set forth in FIG. 11 (SEQ ID NO:11) and fragments or analogs thereof and other variants, for example, from natural isolates of the orf virus which have the biological activity of NZ10 as herein defined. Those skilled in the art will recognize that there is considerable latitude in amino acid sequence charges which can occur naturally or be engineered without affecting biological activity of the polypeptide. It is preferred that the variant polypeptides be at least 80%, more preferably be at least 90%, and most preferably at least 95% identical to the amino acid sequence of FIG. 11 (SEQ ID NO:11). Percent sequence identity is determined by conventional methods. See, for example, Altschul et al, Bull. Math. Bio., 1986 48 603-616 and Henikoff and Henikoff, Proc. Natl. Acad. Sci. USA, 1992 89 10915-10919.
[0043] Such variant forms of ORFV2-VEGF or NZ10 can be prepared by targeting non-essential regions of the ORFV2-VEGF or NZ10 polypeptide for modification. Other variant forms may be naturally made from related orf virus strains. These non-essential regions are expected to fall outside the strongly-conserved regions indicated in FIG. 1. In particular, the growth factors of the PDGF family, including VEGF, are dimeric, and VEGF, VEGF-B, VEGF-C, VEGFD, ORFV2-VEGF, PlGF, PDGF-A and PDGF-B show complete conservation of eight cysteine residues in the N-terminal domains, ie. the PDGF-like domains (Olofsson et al, 1996; Joukov et al, 1996). These cysteines are thought to be involved in intra- and inter-molecular disulfide bonding. In addition there are further strongly, but not completely, conserved cysteine residues in the C-terminal domains. Loops 1, 2 and 3 of each subunit, which are formed by intra-molecular disulfide bonding, are involved in binding to the receptors for the PDGF/VEGF family of growth factors (Andersson et al: Growth Factors, 1995 12 159-164). As noted above, the cysteines conserved in previously known members of the VEGF family are also conserved in ORFV2-VEGF.
[0044] Persons skilled in the art thus are well aware that these cysteine residues should be preserved in any proposed variant form, and that the active sites present in loops 1, 2 and 3 also should be preserved. However, other regions of the molecule can be expected to be of lesser importance for biological function, and therefore offer suitable targets for modification. Modified polypeptides can readily be tested for their ability to show the biological activity of ORFV2-VEGF by routine activity assay procedures such as cell proliferation tests.
[0045] It is contemplated that some modified ORFV2-VEGF or NZ10 polypeptides will have the ability to bind to endothelial cells, e.g. to VEGF receptor-2, but will be unable to stimulate endothelial cell proliferation, differentiation, migration or survival. These modified polypeptides are expected to be able to act as competitive or non-competitive inhibitors of the ORFV2-VEGF or NZ10 polypeptides and growth factors of the PDGF/VEGF family, and to be useful in situations where prevention or reduction of the ORFV2-VEGF or NZ10 polypeptide or PDGF/VEGF family growth factor action is desirable. Thus such receptor-binding but non-mitogenic, non-differentiation inducing, non-migration inducing, non-motility inducing, non-survival promoting, non-connective tissue development promoting, non-wound healing or non-vascular proliferation inducing variants of the ORFV2-VEGF or NZ10 polypeptide are also within the scope of the invention, and are referred to herein as “receptor-binding but otherwise inactive variant”. Because ORFV2-VEGF or NZ10 forms a dimer in order to activate its only known receptor, it is contemplated that one monomer comprises the receptor-binding but otherwise inactive variant modified ORFV2-VEGF or NZ10 polypeptide and a second monomer comprises a wild-type ORFV2-VEGF or NZ10 or a wild-type growth factor of the PDGF/VEGF family. These dimers can bind to its corresponding receptor but cannot induce downstream signaling.
[0046] It is also contemplated that there are other modified ORFV2-VEGF or NZ10 polypeptides that can prevent binding of a wild-type ORFV2-VEGF or NZ10 or a wild-type growth factor of the PDGF/VEGF family to its corresponding receptor on endothelial cells. Thus these dimers will be unable to stimulate endothelial cell proliferation, differentiation, migration or survival. These modified polypeptides are expected to be able to act as competitive or non-competitive inhibitors of the ORFV2-VEGF or NZ10 polypeptide or a growth factor of the PDGF/VEGF family, and to be useful in situations where prevention or reduction of the ORFV2-VEGF or NZ10 polypeptide or PDGF/VEGF family growth factor action is desirable. Such situations include the tissue remodeling that takes place during invasion of tumor cells into a normal cell population by primary or metastatic tumor formation. Thus such the ORFV2-VEGF or NZ10 or PDGF/VEGF family growth factor-binding but non-mitogenic, non-differentiation inducing, non-migration inducing, non-motility inducing, non-survival promoting, non-connective tissue promoting, non-wound healing or non-vascular proliferation inducing variants of the ORFV2-VEGF or NZ10 polypeptide are also within the scope of the invention, and are referred to herein as “the ORFV2-VEGF or NZ10 polypeptide-dimer forming but otherwise inactive or interfering variants”.
[0047] Thus, another aspect of the invention is a ORFV2-VEGF or NZ10 antagonist, wherein the antagonist is an isolated polypeptide which comprises a sequence of amino acids substantially corresponding to the amino acid sequence of FIG. 9 (SEQ ID NO:2) or FIG. 11 (SEQ ID NO:11), repsectively and has the ability to bind to ORFV2-VEGF or NZ10 and to prevent biological activity of ORFV2-VEGF or NZ10.
[0048] As noted above, the orf virus is known to cause a pustular dermatitis in sheep, goats and humans. The lesions induced after infection with orf virus show extensive proliferation of vascular endothelial cells, dilation of blood vessels and dermal swelling. Expression of an orf virus gene able to stimulate angiogenesis may provide an explanation for these histological observations.
[0049] Accordingly, a further aspect of the invention provides a method for treatment of pustular dermatitis and of fluid accumulation caused by viral infection which comprises the step of administering a therapeutically effective amount of an antagonist to ORFV2-VEGF or NZ10 or to the VEGF receptor 2.
[0050] Where ORFV2-VEGF, NZ10 or a ORFV2-VEGF antagonist or NZ10 antagonist is to be used for therapeutic purposes, the dose and route of application will depend upon the condition to be treated, and will be at the discretion of the attending physician or veterinarian. Suitable routes include subcutaneous, intramuscular, intraperitoneal or intravenous injection, topical application, implants etc. Topical application of ORFV2-VEGF or NZ10 may be used in a manner analogous to VEGF.
[0051] Another aspect of the invention provides expression vectors comprising the DNA of the invention or a nucleic acid molecule of the invention, and host cells transformed or transfected with nucleic acids molecules or vectors of the invention. Vectors also comprises a nucleic acid sequence which hybridize under stringent conditions with the sequence of FIG. 8 or FIG. 10. These cells are particularly suitable for expression of the polypeptide of the invention, and include insect cells such as Sf9 cells, obtainable from the American Type Culture Collection (ATCC SRL-171), transformed with a baculovirus vector, and the human embryo kidney cell line 293 EBNA transfected by a suitable expression plasmid. Preferred vectors of the invention are expression vectors in which a nucleic acid according to the invention is operatively connected to one or more appropriate promoters and/or other control sequences, such that appropriate host cells transformed or transfected with the vectors are capable of expressing the polypeptide of the invention. Other preferred vectors are those suitable for transfection of mammalian cells, or for gene therapy, such as adenoviral-, vaccinia- or retroviral-based vectors or liposomes. A variety of such vectors is known in the art.
[0052] The invention also provides a method of making a vector capable of expressing a polypeptide encoded by a nucleic acid according to the invention, comprising the steps of operatively connecting the nucleic acid to one or more appropriate promoters and/or other control sequences, as described above.
[0053] The invention further provides a method of making a polypeptide according to the invention, comprising the steps of expressing a nucleic acid or vector according to the invention in a host cell, and isolating the polypeptide from the host cell or from the host cell's growth medium.
[0054] In yet a further aspect, the invention provides an antibody specifically reactive with ORFV2-VEGF or NZ10. This aspect of the invention includes antibodies specific for the variant forms, fragments and analogues of ORFV2-VEGF or NZ10 referred to above. The term “analog” or “functional analog” refers to a modified form of ORFV2-VEGF or NZ10 in which at least one amino acid substitution has been made such that said analog retains substantially the same biological activity as the unmodified ORFV2-VEGF and/or NZ10 in vivo and or in vitro. Such antibodies are useful as inhibitors or agonists of ORFV2-VEGF or NZ10 and as diagnostic agents for detecting and quantifying ORFV2-VEGF and/or NZ10. Polyclonal or monoclonal antibodies may be used. Monoclonal and polyclonal antibodies can be raised against polypeptides of the invention using standard methods in the art. For some purposes, for example where a monoclonal antibody is to be used to inhibit effects of ORFV2-VEGF and/or NZ10 in a clinical situation, it may be desirable to use humanized or chimeric monoclonal antibodies. In addition the polypeptide can be linked to an epitope tag, such as the FLAG® octapeptide (Sigma, St. Louis, Mo.), to assist in affinity purification. For some purposes, for example where a monoclonal antibody is to be used to inhibit effects of PDGF-C in a clinical situation, it may be desirable to use humanized or chimeric monoclonal antibodies. Such antibodies may be further modified by addition of cytotoxic or cytostatic drugs. Methods for producing these, including recombinant DNA methods, are also well known in the art.
[0055] This aspect of the invention also includes an antibody which recognizes ORFV2-VEGF and which is suitably labeled.
[0056] Polypeptides or antibodies according to the invention may be labeled with a detectable label, and utilized for diagnostic purposes. Similarly, the thus-labeled polypeptide of the invention may be used to identify its corresponding receptor in situ. The polypeptide or antibody may be covalently or non-covalently coupled to a suitable supermagnetic, paramagnetic, electron dense, ecogenic or radioactive agent for imaging. For use in diagnostic assays, radioactive or non-radioactive labels may be used. Examples of radioactive labels include a radioactive atom or group, such as 125 I or 32 p. Examples of non-radioactive labels include enzymatic labels, such as horseradish peroxidase or fluorimetric labels, such as fluorescein-5-isothiocyanate (FITC). Labeling may be direct or indirect, covalent or non-covalent.
[0057] Clinical applications of the invention include diagnostic applications, acceleration of angiogenesis in wound healing, tissue or organ transplantation, or to establish collateral circulation in tissue infarction or arterial stenosis, such as coronary artery disease, and inhibition of angiogenesis in the treatment of cancer or of diabetic retinopathy.
[0058] Conversely, ORFV2-VEGF and/or NZ10 antagonists (e.g. antibodies and/or inhibitors) could be used to treat conditions, such as congestive heart failure, involving accumulations of fluid in, for example, the lung resulting from increases in vascular permeability, by exerting an offsetting effect on vascular permeability in order to counteract the fluid accumulation. Administrations of ORFV2-VEGF could be used to treat malabsorptive syndromes in the intestinal tract as a result of its blood circulation increasing and vascular permeability increasing activities.
[0059] Thus the invention provides a method of stimulation of angiogenesis and/or neovascularization in a mammal in need of such treatment, comprising the step of administering an effective dose of ORFV2-VEGF or NZ10, or a fragment or analog thereof which has the ability to stimulate endothelial cell proliferation, to the mammal.
[0060] Optionally ORFV2-VEGF may be administered together with, or in conjunction with, one or more of VEGF, VEGF-B, VEGF-C, VEGF-D, PlGF, PDGF, FGF and/or heparin.
[0061] Conversely the invention provides a method of inhibiting angiogenesis and/or neovascularization in a mammal in need of such treatment, comprising the step of administering an effective amount of an antagonist of ORFV2-VEGF to the mammal. The antagonist may be any agent that prevents the action of ORFV2-VEGF and/or NZ10, either by preventing the binding of ORFV2-VEGF and/or NZ10 to its corresponding receptor or the target cell, or by preventing activation of the transducer of the signal from the receptor to its cellular site of action. Suitable antagonists include, but are not limited to, antibodies directed against ORFV2-VEGF and/or NZ10; competitive or non-competitive inhibitors of binding of ORFV2-VEGF/NZ10 to the ORFV2-VEGF/NZ10 receptor, such as the receptor-binding but non-mitogenic ORFV2-VEGF or NZ10 variants referred to above; and anti-sense nucleotide sequences complementary to at least a part of the DNA sequence encoding ORFV2-VEGF and/or NZ10.
[0062] The invention also provides a method of detecting ORFV2-VEGF and/or NZ10 in a biological sample, comprising the step of contacting the sample with a reagent capable of binding ORFV2-VEGF, and detecting the binding. Preferably the reagent capable of binding ORFV2-VEGF and/or NZ10 is an antibody directed against ORFV2-VEGF and/or NZ10, particularly preferably a monoclonal antibody. In a preferred embodiment the binding and/or extent of binding is detected by means of a detectable label; suitable labels are discussed above.
[0063] According to yet a further aspect, the invention provides diagnostic means typically in the form of test kits. For example, in one embodiment of the invention there is provided a diagnostic test kit comprising an antibody to ORFV2-VEGF and/or NZ10 and means for detecting, and more preferably evaluating, binding between the antibody and ORFV2-VEGF or NZ10. In one preferred embodiment of the diagnostic means according to the invention, either the antibody or the ORFV2-VEGF or NZ10 is labelled with a detectable label, and either the antibody or the ORFV2-VEGF or NZ10 is substrate-bound, such that the ORFV2-VEGF/ or NZ10/antibody interaction can be established by determining the amount of label attached to the substrate following binding between the antibody and the ORFV2-VEGF and/or NZ10. In a particularly preferred embodiment of the invention, the diagnostic means may be provided as a conventional ELISA kit.
[0064] A method is provided for determining agents that bind to ORFV2-VEGF and/or NZ10. The method comprises contacting ORFV2-VEGF or NZ10 with a test agent and monitoring binding by any suitable means. Agents can include both compounds and other proteins.
[0065] The invention provides a screening system for discovering agents that bind ORFV2-VEGF and/or NZ10. The screening system comprises preparing ORFV2-VEGF or NZ10, exposing ORFV2-VEGF or NZ10 to a test agent, and quantifying the binding of said agent to ORFV2-VEGF or NZ10 by any suitable means.
[0066] Use of this screen system provides a means to determine compounds that may alter the biological function of ORFV2-VEGF or NZ10. This screening method may be adapted to large-scale, automated procedures such as a PANDEX® (Baxter-Dade Diagnostics) system, allowing for efficient high-volume screening of potential therapeutic agents.
[0067] For this screening system, ORFV2-VEGF or NZ10 is prepared as described herein, preferably using recombinant DNA technology. A test agent, e.g. a compound or protein, is introduced into a reaction vessel containing ORFV2-VEGF or NZ10. Binding of the test agent to ORFV2-VEGF or NZ10 is determined by any suitable means which include, but is not limited to, radioactively- or chemically-labeling the test agent. Binding of ORFV2-VEGF or NZ10 may also be carried out by a method disclosed in U.S. Pat. No. 5,585,277, which is incorporated by reference. In this method, binding of the test agent to ORFV2-VEGF or NZ10 is assessed by monitoring the ratio of folded protein to unfolded protein. Examples of this monitoring can include, but are not limited to, amenability to binding of the protein by a specific antibody against the folded state of the protein.
[0068] Those of skill in the art will recognize that IC 50 values are dependent on the selectivity of the agent tested. For example, an agent with an IC 50 which is less than 10 nM is generally considered an excellent candidate for drug therapy. However, an agent which has a lower affinity, but is selective for a particular target, may be an even better candidate. Those skilled in the art will recognize that any information regarding the binding potential, inhibitory activity or selectivity of a particular agent is useful toward the development of pharmaceutical products.
[0069] Where a ORFV2-VEGF or NZ10 or a ORFV2-VEGF antagonist or a NZ10 antagonist is to be used for therapeutic purposes, the dose(s) and route of administration will depend upon the nature of the patient and condition to be treated, and will be at the discretion of the attending physician or veterinarian. Suitable routes include oral, subcutaneous, intramuscular, intraperitoneal or intravenous injection, parenteral, topical application, implants etc. Topical application of ORFV2-VEGF or NZ10 may be used in a manner analogous to VEGF. For example, where used for wound healing or other use in which enhanced angiogenesis is advantageous, an effective amount of ORFV2-VEGF or NZ10 is administered to an organism in need thereof in a dose between about 0.1 and 1000 g/kg body weight.
[0070] The ORFV2-VEGF or NZ10 or a ORFV2-VEGF antagonist or a NZ10 antagonist may be employed in combination with a suitable pharmaceutical carrier. The resulting compositions comprise a therapeutically effective amount of ORFV2-VEGF or NZ10 or a ORFV2-VEGF antagonist or a NZ10 antagonist, and a pharmaceutically acceptable non-toxic salt thereof, and a pharmaceutically acceptable solid or liquid carrier or adjuvant. Examples of such a carrier or adjuvant include, but are not limited to, saline, buffered saline, Ringer's solution, mineral oil, talc, corn starch, gelatin, lactose, sucrose, microcrystalline cellulose, kaolin, mannitol, dicalcium phosphate, sodium chloride, alginic acid, dextrose, water, glycerol, ethanol, thickeners, stabilizers, suspending agents and combinations thereof. Such compositions may be in the form of solutions, suspensions, tablets, capsules, creams, salves, elixirs, syrups, wafers, ointments or other conventional forms. The formulation to suit the mode of administration. Compositions which comprise ORFV2-VEGF or NZ10 may optionally further comprise one or more of PDGF-A, PDGF-B, VEGF, VEGF-B, VEGF-C, VEGF-D, PlGF and/or heparin. Compositions comprising ORFV2-VEGF or NZ10 will contain from about 0.1% to 90% by weight of the active compound(s), and most generally from about 10% to 30%.
[0071] For intramuscular preparations, a sterile formulation, preferably a suitable soluble salt form of ORFV2-VEGF or NZ10, such as hydrochloride salt, can be dissolved and administered in a pharmaceutical diluent such as pyrogen-free water (distilled), physiological saline or 5% glucose solution. A suitable insoluble form of the compound may be prepared and administered as a suspension in an aqueous base or a pharmaceutically acceptable oil base, e.g. an ester of a long chain fatty acid such as ethyl oleate.
[0072] Another aspect of the invention concerns the provision of a pharmaceutical composition comprising either ORFV2-VEGF or NZ10 or a fragment or analog thereof which promotes proliferation of endothelial cells, or an antagonist such as antibody thereto. Compositions which comprise ORFV2-VEGF or NZ10 may optionally further comprise one or more of VEGF, VEGF-B, VEGF-C, VEGF-D and/or heparin.
[0073] In another aspect, the invention relates to a protein dimer comprising ORFV2-VEGF or NZ10, particularly a disulfide-linked dimer. The protein dimers of the invention include both homodimers of ORFV2-VEGF or NZ10 and heterodimers of ORFV2-VEGF or NZ10 and VEGF, VEGF-B, VEGF-C, VEGF-D, PlGF or PDGF, or heterodimers of ORFV2-VEGF and NZ10.
[0074] According to a yet further aspect of the invention there is provided a ORFV2-VEGF and/or NZ10 antagonist which can be an anti-sense nucleotide sequence which is complementary to at least a part of a DNA sequence which encodes ORFV2-VEGF, NZ10 or a fragment or analog thereof which may be used to inhibit, or at least mitigate, ORFV2-VEGF and/or NZ10 expression. In addition an anti-sense nucleotide sequence can be to the promoter region of the ORVF2-VEGF or ORFV10-VEGF gene or other non-coding region of the gene which may be used to inhibit, or at least mitigate, ORFV2-VEGF and/or NZ10 expression. The use of an antagonist of this type to inhibit ORFV2-VEGF expression is favored in instances where ORFV2-VEGF expression is associated with a disease, for example pustular dermatitis. Transformation of such cells with a vector containing an anti-sense nucleotide sequence would suppress or retard angiogenesis, and so would inhibit or retard growth of lesions.
[0075] A still further aspect the invention relates to an isolated ORFV2-VEGF or NZ10 and VEGFR-2 complex. Isolation and purification of complexes could be effected by conventional procedures such as immunoaffinity purification using monoclonal antibodies according to techniques described in standard reference work such as Harlow et al, “Antibodies, a Laboratory Manual”, Cold Spring Harbor Laboratory Press, 1988 and/or Marshak et al, “Strategies for Protein Purification and Characterization”, Cold Spring Harbor Laboratory Press, 1986.
[0076] Polynucleotides of the invention such as those described above, fragments of those polynucleotides, and variants of those polynucleotides with sufficient similarity to the non-coding strand of those polynucleotides to hybridize thereto under stringent conditions all are useful for identifying, purifying, and isolating polynucleotides encoding other, viral forms of VEGF-like polypeptides. Thus, such polynucleotide fragments and variants are intended as aspects of the invention. Exemplary stringent hybridization conditions are as follows: hybridization at 42° C. in 5×SSC, 20 mM NaPO 4 , pH 6.8, 50% formamide; and washing at 42° C. in 0.2×SSC. Those skilled in the art understand that it is desirable to vary these conditions empirically based on the length and the GC nucleotide base content of the sequences to be hybridized, and that formulas for determining such variation exist. See for example Sambrook et al, “Molecular Cloning: A Laboratory Manual”, Second Edition, pages 9.47-9.51, Cold Spring Harbor, N.Y.: Cold Spring Harbor Laboratory (1989).
[0077] It will be clearly understood that nucleic acids and polypeptides of the invention may be prepared by synthetic means or by recombinant means, or may be purified from natural sources.
[0078] It will be clearly understood that for the purposes of this specification the word “comprising” means “included but not limited to”. The corresponding meaning applies to the word “comprises”.
BRIEF DESCRIPTION OF THE DRAWINGS
[0079] [0079]FIG. 1 shows a comparative sequence alignment of the amino acid sequences of ORFV2-VEGF with other members of the VEGF family of growth factors. The deduced amino acid sequence of ORFV2-VEGF was aligned with the sequences of VEGF 121 (SEQ ID NO:3), VEGF 165 (SEQ ID NO:4), PlGF (SEQ ID NO:5), VEGF-B 167 (SEQ ID NO:6), and truncated sequences of VEGF-C (SEQ ID NO:7) and VEGF-D (SEQ ID NO:8). The residues which show identity with ORFV2-VEGF (SEQ ID NO:2) are boxed. The conserved cysteine residues of the cystine knot motif are indicated with an asterisk. The signal sequence as determined by N-terminal sequencing is indicated by the line above the sequence. The potential sites of N- and O-linked glycosylation are indicated by a bracket and dashed line respectively. The VEGF homology domain is indicated by arrows.
[0080] [0080]FIG. 2 shows the analysis and purification of expressed ORFV2-VEGF polypeptides.
[0081] (A) FLAG-tagged ORFV2-VEGF was expressed in COS cells by transient transfection. Cells were biosynthetically labeled with 35 S-cysteine/methionine for 4 hours. Conditioned medium from these cells was immunoprecipitated with either M2-gel or control beads and the washed beads eluted with SDS-PAGE sample buffer under reducing (2% β-mercaptoethanol) or non-reducing conditions. The single arrow indicates the non-reduced form of ORFV2-VEGF and the double arrows the two species of the reduced form.
[0082] (B) Conditioned medium from COS cells transfected with FLAG-tagged ORFV2-VEGF DNA was purified on M2-gel and eluted with free FLAG peptide. The fractions (1: void; 2,3 and 4: purified protein) eluted from the M2-gel were collected, combined with 2×SDS-PAGE sample buffer (reducing), boiled and resolved by SDS-PAGE (4-20% gradient). Proteins were identified by silver staining. Molecular weight markers are indicated. Purified proteins are indicated by arrows.
[0083] [0083]FIG. 3 shows the results of analysis of ORFV2-VEGF protein using the VEGFR2 bioassay. Purified ORFV2-VEGF was tested for its ability to induce proliferation of Ba/F3 cells expressing a chimeric VEGFR-2. Bioassay cells were washed to remove IL-3 and then resuspended in dilutions of the ORFV2-VEGF, purified mouse VEGF 164 or medium alone for 48 hours at 37° C. in a humidified atmosphere of 10% CO 2 . DNA synthesis was quantified by the addition of 1 μCi of 3 H-thymidine and counting the amount incorporated over a period of 4 hours. Values are expressed as mean±standard deviations and are representative of 4 experiments.
[0084] [0084]FIG. 4 shows the VEGFR binding specificity of ORFV2-VEGF. Soluble fusion proteins consisting of the extracellular domain of VEGFRs and the Fc portion of human IgG1 were used to assess the receptor binding specificity of ORFV2-VEGF. Biosynthetically labeled conditioned medium derived from 293EBNA cells transfected with ORFV2-VEGF, mouse VEGF 164 , human VEGF 165 , human VEGFDΔNΔC, human VEGF-CΔNΔC or vector alone were immunoprecipitated with protein A bound to the VEGFR-1-Ig, VEGFR-2-Ig, VEGFR-3-Ig or Neuropilin-1-Ig were eluted from washed beads with SDS-PAGE sample buffer and resolved by SDS-PAGE (4-20%). Only the ORFV2-VEGF and VEGF-DΔNΔC were FLAG-tagged. Dried gels were visualized using phosphorimager analysis. The fusion protein used for each precipitation is listed above each panel.
[0085] [0085]FIG. 5 shows autophosphorylation of the VEGFRs receptor after stimulation by recombinant ORFV2-VEGF. NIH3T3 cells expressing either VEGFR-2 or VEGFR-3 were made quiescent by starvation overnight in Dulbecco's Modified Eagle Medium(DMEM) containing 0.2% Bovine serum albumin. The cells were stimulated with either ORVF2-VEGF (100 ng/ml), VEGF 165 (50 ng/ml), human VEGF-CΔNΔC (100 ng/ml) or mock medium, lysed and immunoprecipitated using receptor-specific antibodies. The immunoprecipates were analyzed by phosphotyrosine immunoblotting. The apparent molecular weights of the tyrosyl phosphorylated VEGFR-2 and VEGFR-3 polypeptides are shown. An asterisk (*) marks a 200 kDa intracelluar form of VEGFR-2, which is not phosphorylated in response to receptor stimulation.
[0086] [0086]FIG. 6 shows the mitogenic effect of purified ORFV2-VEGF on human umbilical vein endothelial cells (HUVECs). HUVECs were exposed to purified ORFV2-VEGF, mouse VEGF 164 or human VEGF-DΔNΔC for 3 days. After 72 hours the amount of cellular proliferation was quantified by a 3-(4,5-dimethylthiazol-2-yl)2,5-diphenyltetrazolium bromide (MTT, Sigma) assay measuring the conversion of a MTT substrate. The dotted line indicates the levels of stimulation achieved with medium alone. Values are expressed as a mean±standard deviations and are representative of 3 experiments.
[0087] [0087]FIG. 7 shows the vascular permeability activity of purified ORFV2-VEGF in the Miles assay. Anesthetized guinea pigs were given intra-cardiac injections of Evans Blue dye. Purified ORFV2-VEGF, mouse VEGF 164 and appropriate controls were diluted in medium and 150 μl were injected intra-dermally into the shaved areas on the back of the animal. After 30 minutes, the animals were sacrificed and the skin excised (FIG. 7A) and then eluted in formamide and (FIG. 7B) the absorbance reading at 620 nm recorded. Values are expressed as mean±standard deviations and are representative of 3 experiments.
[0088] [0088]FIG. 8 shows the nucleotide sequence encoding ORFV2-VEGF (SEQ ID NO:1).
[0089] [0089]FIG. 9 shows the amino acid sequence encoded by the nucleotide sequence of FIG. 8 (SEQ ID NO:2).
[0090] [0090]FIG. 10 shows the nucleotide sequence encoding ORFV10-VEGF (SEQ ID NO:10).
[0091] [0091]FIG. 11 shows the amino acid sequence (SEQ ID NO:11) encoded by the nucleotide sequence of FIG. 10.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0092] [0092]FIG. 1 shows a comparative sequence alignment of the amino acid sequences of ORFV2-VEGF with other members of the VEGF family of growth factors. The deduced amino acid sequence of ORFV2-VEGF was aligned with the sequences of VEGF 121 (SEQ ID NO:3), VEGF 165 (SEQ ID NO:4), PlGF (SEQ ID NO:5), VEGF-B 167 (SEQ ID NO:6), and truncated sequences of VEGF-C (SEQ ID NO:7) and VEGF-D (SEQ ID NO:8). Alignment of the predicted amino acid sequence of ORFV2-VEGF (SEQ ID NO:2) with members of the VEGF family demonstrates that ORFV2-VEGF has a high degree of sequence homology with the VEGF homology domain (VHD) of this family of proteins. ORFV2-VEGF contains all six cysteine residues of the cystine-knot motif which are absolutely conserved among family members. The conserved cysteine residues of the cystine knot motif are indicated with an asterisk (*). Several other invariant or highly conserved amino acids are indicated. ORFV2-VEGF does not contain the extended N- and C-terminal regions seen in VEGF-C and VEGF-D. Overall, ORFV2-VEGF is 43.3%, 34.3%, 25.4%, 26.9% and 33.6% identical to human VEGF 165 (SEQ ID NO:4), VEGFB (SEQ ID NO:6), VEGF-C (SEQ ID NO:7), VEGF-D (SEQ ID NO:8) and PlGF (SEQ ID NO:5), respectively. The amino acid sequence of ORFV2-VEGF is 87% identical to NZ10. This sequence similarity of ORFV2-VEGF and NZ10 to the mammalian VEGFs raises the question of whether the structural relatedness extends to receptor binding and biological function.
[0093] The level of relatedness of ORFV2-VEGF/NZ10 to VEGF 165 suggests the possibility that ORFV2-VEGF/NZ10 is derived from the VEGF 165 gene but that sequence divergence may result in the changes which would affect receptor binding and hence biological function. However, it is also possible that ORFV2-VEGF/NZ10 is derived from another, yet unidentified, mammalian VEGF family member since another orf virus gene (a homolog of IL-10) shows 80% amino acid sequence identity to its mammalian counterpart. These predictions are complicated by the presence of a variant form of the viral VEGF in the NZ7 strain of the orf virus. Stain NZ7 encodes a protein which has only 23% amino acid identity with human VEGF, 43% identity with ORFV2-VEGF, and 40% identity with NZ10.
EXAMPLE 1
Expression and Purification of ORFV2-VEGF and NZ10
[0094] A DNA fragment containing nucleotides 4 to 401 of the sequence shown in FIG. 8 (SEQ ID NO: 1) of the VEGF-like gene of the orf virus strain NZ2, was prepared by polymerase chain reaction (PCR)using pVU89 as a template (Lyttle et al, J. Virol. 1994 68 84-92). This fragment was inserted into the PEFBOS-I-FLAG expression vector immediately upstream from the DNA sequence encoding the FLAG octapeptide. In addition, the cDNA encoding NZ10 (SEQ ID NO:10) was linked at its C-terminal with the sequence encoding the FLAG octapeptide. Protein synthesis gives rise to VEGF-like polypeptides that are tagged with the FLAG octapeptide at its C-terminus. These proteins were designated FLAG-tagged ORFV2-VEGF or FLAG-tagged NZ10. The FLAG-tagged NZ10 construct was subcloned into the pAPEX-3 expression vector and then transiently expressed in 293EBNA-1 cells using Fugene mediated transfection. After 24-72 hours the conditioned medium was collected and the FLAG-tagged proteins were purified using the M2-gel as described below. With respect to the vector including FLAG-tagged ORFV2-VEGF, it was transiently transfected into COS cells using the DEAE-Dextran method as described Aruffo and Seed, Proc. Natl. Acad. Sci. USA, 1987 84 8573-8577 and biosynthetically labeled with 35 S-cysteine/methionine for 4 hours. After 3 days incubation, a portion of the transfected COS cells were metabolically labeled as described by Joukov et al, EMBO Journal 1996 15 290-298. The remaining culture was incubated for a total of 7 days. Conditioned cell culture was collected and clarified by centrifugation before the FLAG-tagged proteins were recovered by immunoprecipitation with either M2-gel (anti-FLAG) or control beads. The conditioned media was tested in the bioassay as described below, and the results demonstrated that the COS cells did in fact express and secrete biologically-active ORFV2-VEGF.
[0095] SDS-PAGE and Immunoblotting
[0096] Purified proteins or washed immunoprecipitates were combined with SDS-PAGE sample buffer under reducing (2% β-mercaptoethanol) or non-reducing conditions, boiled and resolved by SDS-PAGE. When required, proteins were transferred to nitrocellulose and blotted with M2 antibody. Under non-reducing conditions a band exhibiting a M r of approximately 44-48 kDa was observed, while under reducing conditions a faster migrating band exhibiting a M r of approximately 23-26 kDa was seen (see FIG. 2A). The bands detected are consistent with ORFV2-VEGF being a disulfide-linked homodimer with a monomeric M r of approximately 25 kDa. This is larger than the predicted size of 13,456 Da for ORFV2-VEGF and suggests modification by glycosylation. Examination of the ORFV2-VEGF sequence reveals one potential N-linked glycosylation site (Asn85-Thr87) and two potential O-linked glycosylation sites (Thr121-Thr125). N-glycanase treatment reduced the size of the ORFV2-VEGF monomer by about 5 kDa (not shown). The remaining size difference is believed due to O-linked glycosylation, the consensus sequences for which are present in the threonine/proline-rich C-terminus of ORFV2-VEGF. In FIG. 2A, the single arrow indicates the non-reduced form of ORFV2-VEGF and the double arrows the two species of reduced form.
[0097] Unlabeled FLAG-tagged ORFV2-VEGF was enriched from the conditioned medium of transfected COS cells by affinity chromatography with M2 resin followed by elution with FLAG peptide. Analysis of this material by SDS-PAGE and silver staining (FIG. 2B) or Western blotting with anti-FLAG monoclonal antibodies (not shown) demonstrated species of the same M r as that seen following biosynthetic labeling. N-terminal sequencing of the secreted purified protein demonstrated a single sequence, and this was identical with the deduced amino acid sequence from residue 21 to 43 of FIG. 9 (SEQ ID NO:2) and confirmed the prediction that ORFV2-VEGF is a protein with a signal sequence of 20 amino acids.
[0098] For NZ10, the purified VEGF-like polypeptides also were found to be disulfide-linked homodimers (not shown). Under reducing conditions the monomers of NZ10 migrate at M r approximately 30K (not shown).
EXAMPLE 2
Bioassay for ORFV2-VEGF/NZ10 to Binding to VEGF Receptor-2
[0099] ORFV2-VEGF and NZ10 were tested in a bioassay which detects ligands for VEGFR-2. FIG. 3 shows the results of analysis of ORFV2-VEGF protein using the VEGFR2 bioassay. Results with NZ10 are not shown. The bioassay was performed using Ba/F3 cells which express a chimeric receptor consisting of the extracellular domain of mouse VEGFR-2 and the transmembrane and cytoplasmic domains of the mouse erythropoitin receptor (EpoR). The cells were maintained in Dulbecco's Modified Eagle Medium(DMEM) containing 10% fetal bovine serum (FBS), 50 mM L-glutamine, 50 μg/ml gentamicin and 10% of the Walter and Eliza Hall Institute of Medical Research (WEHI)-3D-conditioned medium as a source of interleukin-3 (IL-3). Cells expressing the VEGFR-2-EpoR chimeric receptor were washed 3 times in phosphate buffered saline (PBS), and once in complete medium lacking IL-3. Cells (10 4 ) were aliquoted into 96-well microtiter plates containing dilutions of the test reagent or medium alone. Cells were incubated for 48 hours at 37° C. in a humidified atmosphere of 5% CO 2 . Cell proliferation was quantified by the addition of 1 μCi of 3 H-thymidine for 4 hours prior to harvesting. Incorporation of 3 H-thymidine was determined using a cell harvester and β-counting.
[0100] Activation of the chimeric receptor rescues the cells from their dependence on IL-3 and causes the cells to proliferate in the absence of IL-3. VEGF, VEGF-CΔNΔC (the VEGF homology domain of VEGF-C) and VEGF-DΔNΔC (the VEGF homology domain of VEGF-D) which are all ligands for VEGFR-2, stimulate growth of this cell line in a specific and dose-dependent fashion (Achen et al, Proc. Natl. Acad. Sci. USA 1998 95 548-553). Purified ORFV2-VEGF was able to induce detectable DNA synthesis in the bioassay cell line at a concentration of 25 ng/ml. By comparison, VEGF was able to induce DNA synthesis in the bioassay cell line from a concentration of 5 ng/ml. Overall ORFV2-VEGF was about four-fold less potent in the bioassay compared to mouse VEGF. These results clearly demonstrate that ORFV2-VEGF can bind to and cross-link the extracellular domain of VEGFR-2 and induce a proliferation response. Similar results were found with NZ-2.
EXAMPLE 3
ORFV2-VEGF Binding to Soluble VEGF Receptor-2 Extracellular Domains
[0101] To further assess the interactions between ORFV2-VEGF and the VEGFRs, ORFV2-VEGF was tested for its capacity to bind to soluble Ig-fusion proteins containing the extracellular domains of human VEGFR-1, VEGFR-2 and VEGFR-3. The fusion proteins, designated VEGFR-1-Ig, VEGFR-2-Ig and VEGFR3-Ig, were transiently expressed in 293 EBNA cells. All Ig fusion proteins were human VEGFRs. Cells were incubated for 24 hours after transfection, washed with DMEM containing 0.2% bovine serum albumin and starved for 24 hours. The fusion proteins were then precipitated from the clarified conditioned medium using protein A-Sepharose beads. The beads were combined with 100 μl of 10× binding buffer (5% bovine serum albumin, 0.2% Tween 20 and 10 μg/ml heparin) and 900 μl of conditioned medium from 293 cells that had been transfected with expression plasmids encoding VEGF, VEGF-DΔNΔC, ORFV2-VEGF or control vector, then metabolically labeled with 35 S-cysteine/methionine for 4 to 16 hours. After 2.5 hours, at room temperature, the Sepharose beads were washed 3 times with binding buffer at 4° C., once with phosphate buffered saline and boiled in SDS-PAGE buffer. Labeled proteins that were bound to the Ig-fusion proteins were analyzed by SDS-PAGE under reducing conditions. Radiolabeled proteins were detected using a phosphorimager analyzer.
[0102] As seen in FIG. 4A, polypeptides corresponding to the size of ORFV2-VEGF were precipitated by VEGFR-2-Ig from the medium of cells expressing ORFV2-VEGF. In contrast, VEGFR-1-Ig or VEGFR-3-Ig precipitated no proteins from this medium. As expected a polypeptide of approximately 24 kDa was precipitated by VEGFR-1-Ig and VEGFR-2-Ig from the medium of cells expressing mouse VEGF 164 but was not precipitated by VEGFR-3-Ig. Also, as expected, a polypeptide of approximately 22 kDa was precipitated by VEGFR-2-Ig and VEGFR3-Ig from the medium of cells expressing VEGF-DΔNΔC but was not precipitated by VEGFR-1-Ig. No labeled polypeptides were precipitated by the three fusion proteins from the medium of cells transfected with the expression vector lacking sequences encoding VEGF's. ORFV2-VEGF was also tested for its ability to bind the neuropilin-1 receptor, a recently reported ligand for VEGF (FIG. 4B). The neuropilin-1-Ig fusion protein was able to precipitate VEGF 164 but not ORFV2-VEGF. In total these data indicate that the ORFV2-VEGF can bind to VEGFR-2 but not to VEGFR-1, VEGFR-3 or neuropilin-1. NZ10 was also found not to bind VEGFR-1. This receptor-binding specificity of ORFV2-VEGF and NZ10 is unique among the VEGF family of growth factors. Recent structural analyses of human VEGF identified residues thought to be important in binding to VEGFR-1 and VEGFR-2. In light of the receptor binding properties of ORFV2-VEGF, it is intriguing that the VEGF residues implicated as being critical in binding to VEGFR-1 are partially conserved in ORFV2-VEGF, while those involved in VEGFR-2 binding are not. Experiments which have determined the crystal structure of VEGF and predicted the residues critical for binding VEGFR-2 are Phe17, Ile46, Glu64, Gln79 and Ile83 and for binding VEGFR-1 are Asp63 and Glu64. The mechanism whereby ORFV2-VEGF binds to VEGFR-2 is clearly of interest; the lack of conservation of key residues suggests that the binding site for ORFV2-VEGF is different from that of VEGF.
EXAMPLE 4
ORFV2-VEGF Activates VEGFR-2
[0103] The ability of ORFV2-VEGF to induce tyrosine phosphorylation of human VEGFR-2 and human VEGFR-3 was examined. ORFV2-VEGF, VEGF 165 and VEGF-CΔNΔC were diluted in DMEM containing 0.2% bovine serum albumin and used to stimulate NIH3T3 cells expressing VEGFR-2 or VEGFR-3. After stimulation, cells were lysed and VEGFR-2 or VEGFR-3 were immunoprecipitated and analyzed by Western blot analysis with phosphotyrosine-specific monoclonal antibodies. As shown in FIG. 5, ORFV2-VEGF stimulated tyrosine kinase phosphorylation of VEGFR-2 but not VEGFR-3. As expected, the positive control proteins VEGF 165 and VEGF-CΔNΔC were able to induce phosphorylation of VEGFR-2 and VEGFR-3, respectively. These data demonstrate that ORFV2-VEGF can specifically induce phosphorylation of VEGFR-2.
EXAMPLE 5
Mitogenicity of ORFV2-VEGF for Endothetial Cells
[0104] Members of the VEGF family of proteins show variable degrees of mitogenicity for endothelial cells. The mitogenic capacity of ORFV2-VEGF was tested using human umbilical vein endothelial cells (HUVECs). Cells grown in endothelial cell basal medium-2 (EBM-2, Clonetics) containing SingleQuots plus growth factor supplements and serum were removed with trypsin, washed and aliquoted at 10 3 cells per well in a 96-well plate. Cells were allowed to adhere for 6 to 16 hours at 37° C. in EBM-2 medium plus serum without growth factors before samples of growth factor, diluted in the same medium was added. HUVECs were exposed to purified ORFV2-VEGF, mouse VEGF 164 or human VEGF-DΔNΔC for 3 days at 37° C. and then the cells were dissociated with trysin and counted. The amount of cellular proliferation was quantified by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay measuring the conversion of a MTT substrate. As seen in FIG. 6, ORFV2-VEGF (0.5-100 ng/ml) was able to stimulate an increase in the number of cells after 3 days compared to medium that did not contain added growth factor. Control proteins VEGF 164 and VEGF-CΔNΔC also stimulated the endothelial cells. The proliferative capacity of HUVECs exposed to ORFV2-VEGF was comparable to those grown with mouse VEGF164.
EXAMPLE 6
Vascular Permeability Assay
[0105] As orf virus lesions are characterized by swelling and fluid accumulation, the purified ORFV2-VEGF was tested for its ability to induce vascular permeability in a Miles Assay. Anesthetized guinea pigs were given intra-cardiac injections of 500 μl of 0.5% Evans Blue dye in phosphate buffered saline to introduce the dye into the bloodstream. Purified ORFV2-VEGF, mouse VEGF 164 and appropriate controls were diluted in medium and 150 l were injected intra-dermally into the shaved areas on the back of the animal. After 30 minutes, the animals were sacrificed and the skin excised (FIG. 7A) and then eluted in formamide and (FIG. 7B) the absorbance reading at 620 nm recorded. The aliquots of ORFV2-VEGF contained 8 to 66 ng of factor. In comparison to medium alone there was detectable and dose-dependent permeability induced by the ORFV2-VEGF. ORFV2-VEGF is approximately five-fold less potent as a vascular permeability factor than mouse VEGF 164 .
[0106] [0106]FIG. 8 shows the nucleotide sequence encoding ORFV2-VEGF (SEQ ID NO: 1).
[0107] [0107]FIG. 9 shows the amino acid sequence encoded by the nucleotide sequence of FIG. 8 (SEQ ID NO:2).
[0108] The Examples above strongly suggest that ORFV2-VEGF is capable of inducing activation of the VEGFR-2 signaling pathway analogous to VEGF stimulation. ORFV2-VEGF is also capable of inducing the proliferation of endothelial cells. VEGFR-2 appears to be a major mediator of such activity. The ability of ORFV2-VEGF to induce vascular permeability, combined with its restricted receptor binding specificity, indicates that VEGFR-2 can mediate vascular permeability in the VEGFR family, as has been previously suggested by analysis of VEGF-C mutants. However, the presence of a novel receptor mediating permeability cannot be formally excluded.
[0109] Bioassays to Determine the Function of ORFV2-VEGF
[0110] Other assays are conducted to evaluate whether ORFV2-VEGF or NZ10 has similar activities to VEGF, VEGF-C and/or VEGF-D in relation to endothelial cell function, angiogenesis and wound healing.
[0111] I. Assays of Endothelial Cell Function
[0112] a) Endothelial Cell Proliferation
[0113] Endothelial cell growth assays are performed by methods well known in the art, eg. those of Ferrara & Henzel, Nature, 1989 380 439-443, Gospodarowicz et al Proc. Natl. Acad. Sci. USA, 1989 86 7311-7315, and/or Claffey et al, Biochim. Biophys. Acta, 1995 1246 1-9.
[0114] b) Cell Adhesion Assay
[0115] The effect of ORFV2-VEGF or NZ10 on adhesion of polmorphonuclear granulocytes to endothelial cells is tested.
[0116] c) Chemotaxis
[0117] The standard Boyden chamber chemotaxis assay is used to test the effect of ORFV2-VEGF or NZ10 on chemotaxis.
[0118] d) Plasminogen Activator Assay
[0119] Endothelial cells are tested for the effect of ORFV2-VEGF or NZ10 on plasminogen activator and plasminogen activator inhibitor production, using the method of Pepper et al, Biochem. Biophys. Res. Commun., 1991 181 902-906.
[0120] e) Endothelial Cell Migration Assay
[0121] The ability of ORFV2-VEGF or NZ10 to stimulate endothelial cells to migrate and form tubes is assayed as described in Montesano et al, Proc. Natl. Acad. Sci. USA, 1986 83 7297-7301. Alternatively, the three-dimensional collagen gel assay described by Joukov et al (1996) or a gelatinized membrane in a modified Boyden chamber (Glaser et al, Nature, 1980 288 483-484) may be used.
[0122] II Angiogenesis Assay
[0123] The ability of ORFV2-VEGF or NZ10 to induce an angiogenic response in chick chorioallantoic membrane is tested as described in Leung et al, Science, 1989 246 1306-1309. Alternatively the rat cornea assay of Rastinejad et al, Cell, 1989 56 345-355 may be used; this is an accepted method for assay of in vivo angiogenesis, and the results are readily transferrable to other in vivo systems.
[0124] III Wound Healing
[0125] The ability of ORFV2-VEGF or NZ10 to stimulate wound healing is tested in the most clinically relevant model available, as described in Schilling et al, Surgery, 1959 46 702-710 and utilized by Hunt et al, Surgery, 1967 114 302-307.
[0126] IV The Haemopoietic System
[0127] A variety of in vitro and in vivo assays using specific cell populations of the haemopoietic system are known in the art, and are outlined below. In particular a variety of in vitro murine stem cell assays using fluorescence-activated cell sorter purified cells are particularly convenient:
[0128] a) Repopulating Stem Cells
[0129] These are cells capable of repopulating the bone marrow of lethally irradiated mice, and have the Lin − , Rh h1 , Ly-6A/E + , c-kit + phenotype. ORFV2-VEGF or NZ10 is tested on these cells either alone, or by co-incubation with other factors, followed by measurement of cellular proliferation by 3 H-thymidine incorporation.
[0130] b) Late Stage Stem Cells
[0131] These are cells that have comparatively little bone marrow repopulating ability, but can generate D13 CFU-S. These cells have the Lin − , Rh h1 , Ly-6A/E + , c-kit + phenotype. VEGF-D is incubated with these cells for a period of time, injected into lethally irradiated recipients, and the number of D13 spleen colonies enumerated.
[0132] c) Progenitor-Enriched Cells
[0133] These are cells that respond in vitro to single growth factors and have the Lin − , Rh h1 , Ly-6A/E + , c-kit + phenotype. This assay will show if ORFV2-VEGF or NZ10 can act directly on haemopoietic progenitor cells. ORFV2-VEGF or NZ10 is incubated with these cells in agar cultures, and the number of colonies present after 7-14 days is counted.
[0134] V Atherosclerosis
[0135] Smooth muscle cells play a crucial role in the development or initiation of atherosclerosis, requiring a change of their phenotype from a contractile to a senescent state. Macrophages, endothelial cells, T lymphocytes and platelets all play a role in the development of atherosclerotic plaques by influencing the growth and phenotypic modulations of smooth muscle cell. An in vitro assay using a modified Rose chamber in which different cell types are seeded on to opposite coverslips measures the proliferative rate and phenotypic modulations of smooth muscle cells in a multicellular environment, and is used to assess the effect of ORFV2-VEGF or NZ10 on smooth muscle cells.
[0136] VI Metastasis
[0137] The ability of ORFV2-VEGF or NZ10 to inhibit metastasis is assayed using the Lewis lung carcinoma model, for example using the method of Cao et al, J. Exp. Med., 1995 182 2069-2077.
[0138] VII ORFV2-VEGF or NZ10 in Other Cell Types
[0139] The effects of ORFV2-VEGF or NZ10 on proliferation, differentiation and function of other cell types, such as liver cells, cardiac muscle and other cells, endocrine cells and osteoblasts can readily be assayed by methods known in the art, such as 3 H-thymidine uptake by in vitro cultures.
[0140] VIII Construction of ORFV2-VEGF or NZ10 Variants and Analogs
[0141] ORFV2-VEGF and NZ10 are members of the VEGF family of growth factors which exhibits a high degree of homology to the other members of the VEGF family. Both ORFV2-VEGF and NZ10 contain eight conserved cysteine residues which are characteristic of this family of growth factors. These conserved cysteine residues form intra-chain disulfide bonds which produce the cysteine knot structure, and inter-chain disulfide bonds that form the protein dimers which are characteristic of members of the PDGF family of growth factors. ORFV2-VEGF and NZ10 will interact with protein tyrosine kinase growth factor receptors, and may also interact with other non-tyrosine kinase receptors.
[0142] In contrast to proteins where little or nothing is known about the protein structure and active sites needed for receptor binding and consequent activity, the design of active mutants of ORFV2-VEGF or NZ10 is greatly facilitated by the fact that a great deal is known about the active sites and important amino acids of the members of the PDGF family of growth factors.
[0143] Published articles elucidating the structure/activity relationships of members of the PDGF family of growth factors include for PDGF: Oestman et al, J. Biol. Chem., 1991 266 10073-10077; Andersson et al, J. Biol. Chem., 1992 267 11260-1266; Oefner et al, EMBO J., 1992 11 3921-3926; Flemming et al, Molecular and Cell Biol., 1993 13 4066-4076 and Andersson et al, Growth Factors, 1995 12 159-164; and for VEGF: Kim et al, Growth Factors, 1992 7 53-64; Pötgens et al, J. Biol. Chem., 1994 269 32879-32885 and Claffey et al, Biochem. Biophys. Acta, 1995 1246 1-9. From these publications it is apparent that because of the eight conserved cysteine residues, the members of the PDGF family of growth factors exhibit a characteristic knotted folding structure and dimerization, which result in formation of three exposed loop regions at each end of the dimerized molecule, at which the active receptor binding sites can be expected to be located.
[0144] Based on this information, a person skilled in the biotechnology arts can design ORFV2-VEGF or NZ10 mutants with a very high probability of retaining ORFV2-VEGF or NZ10 activity by conserving the eight cysteine residues responsible for the knotted folding arrangement and for dimerization, and also by conserving, or making only conservative amino acid substitutions in the likely receptor sequences in the loop 1, loop 2 and loop 3 region of the protein structure.
[0145] The formation of desired mutations at specifically targeted sites in a protein structure is considered to be a standard technique in the arsenal of the protein chemist (Kunkel et al, Methods in Enzymol., 1987 154 367-382). Examples of such site-directed mutagenesis with VEGF can be found in Pötgens et al, J. Biol. Chem., 1994 269 32879-32885 and Claffey et al, Biochim. Biophys. Acta, 1995 1246 1-9. Indeed, site-directed mutagenesis is so common that kits are commercially available to facilitate such procedures (eg. Promega 1994-1995 Catalog., Pages 142-145).
[0146] The endothelial cell proliferating activity of ORFV2-VEGF or NZ10 mutants can be readily confirmed by well established screening procedures. For example, a procedure analogous to the endothelial cell mitotic assay described by Claffey et al, (Biochim. Biophys. Acta., 1995 1246 1-9) can be used. Similarly the effects of ORFV2-VEGF or NZ10 on proliferation of other cell types, on cellular differentiation and on human metastasis can be tested using methods which are well known in the art.
[0147] ORFV2-VEGF or NZ10 Contribution to Viral Lesions
[0148] It seems likely that the biological activities of ORFV2-VEGF or NZ10 contribute to the proliferative and highly vascular nature of orf viral lesions. This is supported by recent analysis of a recombinant orf virus in which the gene encoding ORFV2-VEGF has been deleted. Comparisons of lesions resulting from infection of sheep by wild type and recombinant ORFV2-VEGF-deficient orf virus indicate that in the absence of ORFV2-VEGF, skin lesions are significantly less vascularized.
[0149] The identification of a viral VEGF protein that is capable of subverting mammalian VEGF receptors to aid in its viral infection also raises the possibility that other viruses may act in a similar fashion.
[0150] The foregoing description and examples have been set forth merely to illustrate the invention and are not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed broadly to include all variations falling within the scope of the appended claims and equivalents thereof. | The invention is based on the discovery that a viral VEGF-like protein from the orf virus strain NZ2 and from the orf virus strain NZ10 is capable of binding to the extracellular domain of the VEGF receptor-2 to form bioactive complexes which mediate useful cellular responses and/or antagonize undesired biological activities. Disclosed are methods which stimulate or inhibit these biological activities, methods for therapeutic applications and antagonists of ORFV2-VEGF and/or NZ10. | 2 |
BACKGROUND OF THE INVENTION
The invention relates to an apparatus for the controlled moving of a warp thread. It also refers to a weaving machine with an apparatus of this kind and to uses of the apparatus.
Leno apparatuses are used for the formation of selvedges: An eyed needle, which guides a warp thread in an eye, and a follower needle form a leno weave in interaction with a weft thread (see e.g. EP-A 0 737 764). The needles are moved by drive units which, in known weaving machines, comprise cable runs, control cams, rollers and levers. These mechanical components are expensive and prone to wear. When operating parameters (among others, heald stroke, shed geometry) are changed, time-consuming adjustments must be made by hand.
It is also known to use linear motors as drive units. An electronic processor, which is already used for the control of the weaving machine, can also be used for the control of the linear motors. In this it is however disadvantageous that control loops with special position sensors are required for the setting of warp thread layers using means which act point-wise—for example eyed needles (cf. WO 96/38608)
SUMMARY OF THE INVENTION
The object of the invention is to provide a further apparatus by means of which warp threads—in particular for the formation of cloth edges—are controlledly movable by means of a punctuate compulsory guidance (i.e. with means acting point-wise) and in which the named disadvantages are absent.
This apparatus, controlled by means of a punctuate compulsory guidance, moves a warp thread between three positions, namely a middle position, an upper position and a lower position. It comprises a pendulum which is pivotal about an axis and into which an electrical coil is integrated as well as stationary permanent magnets. The named positions are given by equilibrium positions of the pendulum, with forces which act on the pendulum in these positions in each case being in equilibrium. The equilibrium positions for the upper and the lower positions respectively can be produced by means of forces between the permanent magnets and the current carrying coil; the equilibrium position for the middle position is given by the pendulum with a current-less coil.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an apparatus in accordance with the invention,
FIG. 2 shows a variant of this apparatus,
FIG. 3 shows a plurality of apparatuses which are arranged in parallel (for a Jacquard shed forming apparatus),
FIGS. 4-6 illustrate details of a further variant of the apparatus in accordance with the invention,
FIGS. 7, 8 illustrate two particular possibilities of connecting displaceable elements to a pendulum of the apparatus in accordance with the invention,
FIG. 9 shows a rotator apparatus;
FIG. 10 illustrates a half rotator apparatus in the rotator apparatus of FIG. 9 .
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows an apparatus 1 for the controlled moving of a warp thread 9 which comprises the following components: a pendulum 2 which is pivotal about an axis 20 into which a coil 3 which is arranged on a non-ferromagnetic sheet metal members 21 or between two such sheet metal member 21 respectively is integrated; permanent magnets 4 on a spatially fixed carrier plate 7 ; vertically displaceable elements 5 and 5 ′ which are in active contact with a bow 22 of the pendulum 2 via flexible bands 6 and 6 ′; and springs 65 . The bands 6 and 6 ′, which serve as draw means, can also be designed as cables.
A warp thread 9 , which is drawn in into an eye 50 of the element 5 and is compulsorily guided by the latter, can be punctuately moved between three positions, namely between a middle, an upper as well as a lower position. These positions are given by equilibrium positions of the pendulum 2 which set in as a result of the forces acting on the pendulum 2 . The middle position is given on the one hand by gravitational forces and on the other hand by draw forces of the springs 65 . The one coil 3 , which carries direct current, produces together with the permanent magnets 4 additional magnetic forces, through which the equilibrium position is displaced to the upper right or left respectively. Through a polarity reversal of the current in the coil 3 the pendulum 2 changes from the one to the other of these two equilibrium positions. The band 6 , which can partially lie in contact on the lower side 23 of the bow 22 , which is laterally secured with a screw 62 at the pendulum 2 and which is deflected via a roller 61 into the vertical direction, converts the pendulum movement into a linear movement of the element 5 . The equilibrium positions of the pendulum 2 are thus transferred to three stable positions of the eye 50 , through which the three named positions of the warp thread 9 are given. Sensors are not necessary for a regulation of these positions.
The strip-like or groove-like support surface 23 for the draw means 6 advantageously lies on a curve which is at least approximately a circle about the pendulum axis 20 . In particular the pendulum axis 20 can stand on the center of this circle. In this case the stroke of the eye 50 , i.e. the distance between its middle and upper (or lower) position, is proportional to the radius of the named circle. The stroke is in addition proportional to the pivotal angle of the pendulum 2 , which is determined by the location and shape of the magnets.
The current-less state of the coil 3 and thereby the middle position of the eye 50 is advantageously associated with the shed closure position of a shed which is formed by warp threads 9 .
Two elements 5 and 5 ′ for the moving of two warp threads 9 can be provided, with the movement taking place in a counter-similar manner or anti-symmetrical shape: when the coil 3 carries a current the one warp thread 9 is in the upper, the other in the lower position; when the coil 3 is current-less the two warp threads are in the middle position at the same time. When the polarity of the coil 3 is reversed the two warp threads move in opposite directions.
In contrast to linear motors, the weight of the movable part, namely the pendulum 2 , does not have to be taken up by electromagnetic forces in the apparatus in accordance with the invention.
In the variant of the apparatus 1 in accordance with the invention shown in FIG. 2 the pendulum 2 is a segment plate of a non-ferromagnetic material in which the coil 3 (with connection wires 30 ) is embedded. The deflection rollers 61 , 61 ′ have horizontally displaceable axes. A second roller pair 63 have axes with fixed positions.
A plurality of apparatuses in accordance with the invention, by means of which a plurality of warp threads can be moved at the same time, can be space-savingly arranged in parallel, as is schematically illustrated in FIG. 3 .
A side view of a pendulum 2 , as is contained in the apparatus 1 of FIG. 1, is shown in FIG. 4. A configuration of permanent magnets 4 , 4 a for this pendulum 2 which are arranged on the carrier plate 7 is illustrated in FIG. 5; and a horizontal cross-section through this pendulum 2 is shown in FIG. 6 with the permanent magnets 4 , 4 a which are arranged on both sides.
The electrical coil 3 is designed as a flat ring. The magnetic field which can be produced with the coil 3 is oriented at least approximately parallel to the pendulum axis 20 at the center of the ring. The permanent magnets 4 , 4 a are designed in disc shape and are arranged parallel to the coil 3 . The magnetizations of the permanent magnets 4 , 4 a are oriented the same as the named magnetic field of the coil or opposite to the latter respectively. The permanent magnets 4 , 4 a are advantageously arranged on both sides of the pendulum on ferromagnetic carrier plates 7 and form in each case a similar configuration. In FIG. 6 the magnetizations of the permanent magnets 4 , 4 a are given by arrows 41 , 42 . Arrows 47 represent a magnetization of the ferromagnetic carrier plates 7 . The two adjacent permanent magnets 4 and 4 a are arranged in the reversal region of the pendulum 2 ; they have magnetizations which are oriented oppositely to one another. The smaller partner 4 a of this permanent magnet pair serves as a brake magnet for the pendulum 2 . With this a situation is achieved in which the pendulum 2 comes to rest rapidly in the upper equilibrium position as a result of a damping action. In addition, the permanent magnet pair 4 and 4 a ensure a more precise reversal or end position of the pendulum 2 .
In order that the transition between the three equilibrium positions can take place without disturbing transient oscillations, the sheet metal laminae 21 are manufactured of a material which is a good electrical conductor but is not ferromagnetic. Aluminum can for example be chosen as a material. Eddy currents which are induced in these sheet metal laminae 21 during the movement of the permanent magnets 4 , 4 a in the magnetic field damp the movement of the pendulum 2 . A gap 24 is provided in the sheet metal laminae 21 —see FIG. 4 —in order that a ring current does not form through induction during the switching on or over of the coil current, which would represent an unnecessary dissipation of energy.
With the apparatus 1 illustrated in FIG. 7 a heald 5 is controlled which contains the eye 50 , and at both ends of which the bands 6 , 6 ′ grip on. The band 6 ′ is deflected via rollers by 180°. In the apparatus 1 of FIG. 8 the non-illustrated warp thread (or group of warp threads) is moved with an element 51 , the weight of which must be taken into account when setting the middle position. The springs 65 and 65 ′ can be chosen and set in such a manner that when the coil 3 carries no current the pendulum 2 is in an equilibrium position in which for example the center of gravity of the pendulum is located vertically beneath the axis 20 .
FIG. 9 shows the use of apparatuses 1 , 1 ′ in accordance with the invention in half rotator apparatuses 8 and 8 ′: By means of a first apparatus 1 the warp thread 9 ′ is moved with an eyed needle 5 . A hooked needle 5 b (with a double hook 51 ), which cooperates in a known manner with the eyed needle 5 , is actuated by a second apparatus 1 ′. With this second apparatus 1 ′ elements 5 a and 5 a , which carry auxiliary edge heald frames 55 , 55 ′, are simultaneously moved up and down in a counter-similar manner. The pendulum 2 ′ of the apparatus 1 ′ comprises two segment plates 2 a , 2 b with different radii. The hooked needle 5 b is in connection with the segment plate 2 b with the larger radius. Accordingly, a greater stroke results than for the auxiliary edge heald frames 55 , 55 ′. Such different strokes are preferred for the production of a leno edge. A plate 80 which is fixed in space—see also the oblique view in FIG. 10 —is arranged between the half-cross leno elements 8 and 8 ′. Required deflections of the warp threads 9 , 9 a result through edges of this plate 80 in a known manner.
An apparatus for the formation of a leno selvedge is also known which comprises two lifter healds, which are to be moved counter-similarly, and a half heald (DE-A 40 00 035). This apparatus can be actuated with only one apparatus in accordance with the invention.
The equilibrium position with current-less coil can be influenced with additional permanent magnets. In this at least one magnet must be arranged on the pendulum: for example in the inner region of the ring-shaped coil (no figure).
In the examples described the warp threads are moved individually. They can also be moved combined together group-wise, such as for example is known for Jacquard shed formation apparatuses. The elements for the moving of warp threads are replaced in this by members by means of which in each case a group of warp threads can be moved at the same time.
Weaving machines can be equipped with a plurality of apparatuses in accordance with the invention. This is particularly advantageous when the weaving machine is operated by means of an electronic and programmable control system. A processor for a control system of this kind can also be used for the control of the apparatuses in accordance with the invention. The currents of the coils can thus be programmed so as to be automatically settable, and indeed in such a manner that they assume values which are correspondingly predetermined for the warp thread types. | An apparatus moves a warp thread in a controlled manner by a punctuate compulsory guidance between three positions, namely a middle, an upper and a lower position. It comprises a pendulum which is pivotal about an axis and into which an electrical coil is integrated and stationary permanent magnets. The named positions are given by equilibrium positions of the pendulum, with forces which act on the pendulum in these positions being in each case in an equilibrium. The equilibrium positions for the upper or the lower position respectively can be produced by forces between the permanent magnets and the currently carrying coil; the equilibrium position for the middle position is given by the pendulum with a current-less coil. | 3 |
FIELD OF THE INVENTION
This invention significantly increases the efficiency of structural composite systems applied to building construction. The construction of floors or roofs of composite structure for buildings requires the combination, by means of connectors, of steel beams and reinforced concrete slabs; for the construction of shear walls, which have to resist the horizontal forces applied to the composite structure of a building, the system requires to combine steel columns with reinforced concrete diaphragms.
DESCRIPTION OF THE PRIOR ART
U.S. Pat. No. 4,592,184 considers a vertical plate connector with protrusions but without holes so the horizontal longitudinal shear of the composite beam is taken only by sliding friction and bond; the welded wire fabric has the objective of controlling the cracks that could appear along the plate-connector but it is not meant to take the slab negative bending nor to work as plate-connector of the composite steel-beam-reinforced-concrete-slab system. The same happens with U.S. Pat. No. 5,544,464 where the beam's “s” shaped plate-connector lacks of holes and the welded wire fabric is not there to take the slab's negative flexural bending.
U.S. Pat. No. 4,527,372 does not use a plate-connector: it uses the conventional stud connectors; also, it does not use wire fabric or any other type of reinforcement to solve the negative flexural bending of the slab; it only modifies the steel deck edges to avoid leaking during concrete pouring.
In U.S. Pat. No. 6,112,482, steel deck is supported at the bottom flange of the beam and, instead of using shear connectors, it uses grooves on the top flange and simple bond on the beam's web in order to solve the horizontal longitudinal shear and there are no holes nor longitudinal plate-connector, so the system limits itself to beams of minor spans because the deck's depth limits the beam's span.
Patent EP1227198A2 considers an inverted T profile with two types of holes in the web of the T: closed holes and open holes; the closed holes are useful for generating the “perfobond effect” which generates “concrete dowels” which helps in taking the horizontal longitudinal shear of the composite beam, shear strength based exclusively on the shear strength of concrete. “U” shaped holes facilitates the installation of the welded wire fabric from above; these welded wire fabric's transverse rebars take the negative flexural bending of the slab and for this reason the inventor splices them with the rebars of the prefabricated reinforced concrete planks but in no case he considers these transverse rebars, nor could do so, as the beam's horizontal connectors; for this reason this composite system can only be used for small spans and loads because longitudinal shear capacity is limited by the strength due to the sliding friction or bond between the steel of the beam and the concrete, which are numerically similar, and concrete's longitudinal shear strength. Even though this composite system has holes in its plate-connector, this system does not use rebars as connectors since it uses the welded wire fabric, so the bearing concept on the holes can not he applied because the diameter of the rebars of the wire fabric is much smaller than the holes' diameter. “U” holes are constructively attractive because they allow to place the wire fabric from above which also makes the shear strength of reinforced concrete to be incremented by the wire fabric rebars' shear strength, but these rebars do not work as connectors.
U.S. Pat. No. 3,596,421 uses an omega profile mounted on the web of an inverted T profile. The omega profile's flanges support, at each side, the steel deck; over the edge of the omega profile a wave shaped rebar is welded; this rebar will take the horizontal longitudinal shear of the composite beam, but they are not intended to take the slab's flexural bending and here is the difference with the proposed system.
Finally, none of these patents has a device for leveling the slab or the diaphragm thickness; neither have they fixed the position of the welded wire fabric.
There is still room for improvement in the art.
SUMMARY OF INVENTION
Composite structural system for floors or roofs comprising steel beams and reinforced concrete slab or shear walls comprising steel columns and reinforced concrete diaphragms. In both cases a steel plate with holes crossed with rebars is welded to the steel beam or to the steel column which performs the integral combination of the concrete, the structural element and the rebars.
BRIEF DESCRIPTION OF DRAWINGS
Without restricting the full scope of this invention, the preferred form of this invention is illustrated in the following drawings:
FIG. 1 . It is a perspective of two parallel simply supported steel “I” beams with its plate-connectors welded to the top flanges; the long and short rebars are seen as they cross the holes of the plate-connector; all rebar-connectors are tied up with wires to the longitudinal rebars which are supported by “chairs” sitting on top of the steel deck's ridges transverse reinforcement for temperature can also be seen; reinforced concrete of the slab can also be seen with the edge of the plate-connector at the same finish level of the slab. Steel deck and its support on the beams can also be seen.
FIG. 2 . It is a general perspective of the composite structural system since there are beams that frame to a column and there is a secondary beam being supported by a main beam. It can also be seen the long and short longitudinal rebar-connectors that take the negative flexural bending of the beam which perform at the same time as the rebar-connectors of the transverse beam. All the elements described in FIG. 1 can also be seen.
FIG. 3 . It is a perspective of the connection between the steel composite column and the reinforced concrete diaphragm. The vertical rebars and the rebar-connectors that also perform as spacers for the formwork can be seen.
FIG. 4 . It is a perspective that shows how the end extension of the plate-connector provides support to the secondary beam during erection by bearing these end extensions on the top flange of the main beam while keeping the finish level of the slab which is the same level of the top edge of the plate-connectors with holes.
FIG. 5 . It is a perspective of the connection of a steel column with the frame beams which take the negative flexure. The plate-connector with two levels of holes and the weld of the moment resistant connection that join the flanges of the beam to the faces of the columns can be seen.
FIG. 6 . Shows A-A cross section of the connection of the frame beams with the steel column. The rebar-connectors that take the negative bending of the slab using the lower level of holes and the cross section of the transverse rebar-connectors can be seen. The support “chairs” for the rebar-connectors and the steel deck can also be seen.
FIG. 7 . It is a perspective of how the support “chairs” of the rebar-connector look, and how they ring them around and how they bear on the steel deck.
DETAILED DESCRIPTION
The following description is demonstrative in nature and is not intended to limit the scope of the invention or its application of uses.
There are a number of significant design features and improvements incorporated within the invention.
In simply supported beams ( 14 ) the plate-connector ( 1 , 22 ) with holes ( 2 and 3 ) is welded to the top flange of the beam ( 14 ) and in combination with the rebars ( 4 and 5 ) which go across the holes of the plate-connector it performs the following structural and constructive functions:
The bottom half of the plate-connector ( 1 , 22 ), in all its length, which equals the span of the beam and on its two faces, takes the compression due to the slab ( 7 ) negative flexural bending whose maximum value is located precisely in the vertical plane which coincides with the plane of the plate-connector ( 1 , 22 ). The plate-connector ( 1 , 22 ) takes in all its length and on its two faces, through sliding friction with the slab's concrete, the longitudinal horizontal and vertical shear stresses of the composite beam up to the allowable limits of these stresses. The plate-connector ( 1 , 22 ) should have the required thickness to resist all the vertical and horizontal longitudinal shear of the composite beam. The plate-connector ( 1 , 22 ) must have the required thickness to resist the bearing stress on the holes ( 2 and 3 ) which is caused by the rebar connectors as they work as complementary elements of the composite system resisting the excess of the longitudinal horizontal and vertical shear, not covered by bond and sliding friction between the reinforced concrete of the slab ( 7 ) and the plate-connector ( 1 , 22 ). The fillet welds ( 15 ) that join the plate-connector ( 1 ) to the beam's ( 14 ) top flange must have the required section to resist the total longitudinal horizontal shear and all the composite beam's ( 14 ) vertical transverse shear. The plate-connector ( 1 , 22 ) and the top flange can be cut in one piece from an I beam profile or it can be a steel plate of rectangular cross section welded edgewise to a beam's top flange of a steel I beam or to the top flange of a plate girder with equal or unequal flanges. The plate-connector ( 1 , 22 ) can be welded to the beam's ( 14 ) top flange with one fillet weld at each side or only one fillet weld at one side, according to design and constructive facility. The plate-connector ( 1 , 22 ) cantilevers out slightly at its ends ( 17 ) so these extensions can perform as beam supports during its erection: This support system allows to keep a constant level for all the concrete slab. The holes ( 2 , 3 ) of the plate-connector ( 1 , 2 ) hold in its correct position and level all the rebar-connectors ( 4 , 5 ) during the concrete pouring of the slab ( 7 ) and this guarantees that the calculated negative flexural bending strength of the slab ( 7 ) becomes a reality because its flexural arm will be exactly in the design position and complying with code cover-over-bars requirements; this structural and constructive system eliminates the typical cracks which appear in slabs along the beam's ( 14 ) longitudinal axis in regular composite systems; these cracks are the result of the difficulty in maintaining the reinforcing wire fabric at its design horizontal position during the concrete pouring, in spite of the use of “chairs”, and this is due to the great flexibility of the welded wire fabric, also product of the small diameters of its rebars. The rebar-connectors ( 4 , 5 ) which go across the holes of the plate-connector ( 1 , 22 ) take: In first place the tension caused by the transverse negative flexural bending of the slab ( 7 ) whose maximum is located precisely at the beam's axis ( 11 ); secondly the tension caused by shrinkage and creep in the concrete of the slab ( 7 ); in the third place the shear, the bearing and bond caused by the horizontal longitudinal shear stress in the composite beam ( 11 ) and in fourth place the bending, shear and bond caused by the vertical shear in the composite beam ( 11 ) which tries to separate it from the slab ( 7 ). The rebar connectors crossing the holes of the plate-connector ( 4 ) do not allow the separation of the plate-connector and the reinforced concrete, which can be the result of the simultaneous action of the slab's reinforced concrete flexural bending, the slab's drying shrinkage and creep, or the beam's longitudinal horizontal and vertical shear; the separation of the slab and the plate-connector, would eliminate bond and sliding friction which will produce the destruction of the integral composite system. The plate-connector ( 1 , 22 ) may have only one level of holes ( 2 ) in the mid third of the span of the beam where rebar-connectors ( 4 , 5 ) do not cross with other transverse rebar-connectors. Frame beams ( 11 and 12 ) with moment connections to columns ( 13 ), mostly in orthogonal directions, have a negative bending at the support, so the plate-connector ( 1 , 22 ) with holes, welded to the top flange of the beams in combination with the rebars of the slab ( 16 ) which go across the plate-connector in two levels, meet the following objectives: The rebar-connectors ( 4 , 5 ) take the tension caused by the beam's ( 11 ) longitudinal negative flexure and, at the same time, by means of the plate-connector ( 1 , 22 ), the shear, bond and bearing, product of the transverse beam ( 12 ) horizontal shear and vice versa: the maximum tension in rebar connectors ( 4 ) is limited to one half of the usual shear strength when only tension is involved. The rebar-connectors ( 4 ) take the tension caused by shrinkage, creep and temperature changes in the slab in all directions. The rebar-connectors take the flexure, shear and bond caused by the vertical shear of the beam ( 11 and 12 ) which tries to separate it from the slab. The holes ( 2 , 3 ) of the plate-connector secure that each layer of rebar-connectors ( 16 ) will be placed in its exact level, keeping the mechanical arm fixed and therefore, the maximum calculated flexural bending capacity for each beam ( 11 and 12 ) and the code concrete cover. The rebar-connectors ( 16 ) control the slab ( 7 ) cracking due to flexural bending or to diagonal tension in its plane caused by shear stress in both directions. The rebar-connectors ( 16 ) can have different lengths which depends on the variation of the magnitude of the negative bending of the composite system along the axis of the beam.
The rebars ( 8 ) parallel to the beam's axis should be tied with steel wire to the rebar-connectors ( 4 and 5 ) and the rebars of the bottom ( 8 ) should be supported by “chairs” ( 10 ); the system performs with the following functions:
To keep all of the rebar-connectors ( 4 and 5 ) with a proper parallelism and angle in relation to the beam's axis. To supply support and horizontal stability to rebar-connectors ( 3 and 4 ) during the pouring of the slab, the “chairs” ( 10 ) hold together these rebars ( 8 ) and give them support and spacing; the “chairs” should be placed on the top of the ridges of the steel deck ( 6 ). To supply the slab ( 7 ) with the required reinforcement ( 8 and 9 ) in order to take the stresses caused by temperature changes. To create a rebar mesh ( 8 and 9 ) with the transverse rebars ( 9 ) that go on top of the steel deck ( 6 ) but with those ( 9 ) that are not rebar-connectors ( 14 ) and go across the top layer of holes of the plate-connector and ( 2 and 3 ) cover the central portion of the span of the slab along all its length ( 7 ): it is important to keep the splice of these transverse rebars ( 10 ), across the width of the slab's transformed section ( 7 ), in order to keep there the same longitudinal horizontal shear strength. To distribute the stresses caused by point loads on the slab ( 9 ) thus avoiding cracking and disintegration in the reinforced concrete of the slab.
The plate-connector ( 1 , 22 ) with holes crossed by rebar-connectors ( 21 ) and joined to a steel column profile ( 13 ) has the following structural functions:
The set plate-connector ( 1 , 22 ) with its rebar-connectors across its holes solve all of the following forces: longitudinal shear, transverse shear, drying shrinkage and creep of the reinforced concrete diaphragm. The rebar-connectors which go across the holes ( 2 and 3 ) of the plate-connector ( 1 , 22 ) take in shear and bearing strength the longitudinal and transverse shear of the diaphragm ( 18 ) as well as the stresses caused by drying shrinkage and creep of the reinforced concrete ( 18 ) of the diaphragm. The rebar-connectors across the plate-connector ( 1 , 22 ) with their length define the diaphragm thickness ( 18 ) since they act like limits to the formwork. The rebar-connectors ( 21 ) maintain the reinforced concrete bonded to the plate-connector ( 1 , 22 ) preserving its sliding friction and bond. The holes ( 2 and 3 ) of the plate-connector ( 1 , 22 ) must have a minimal web diameter that would make possible the tightest rebar connectors manual fitting ( 21 ) to maintain the concept of bearing connector valid.
Although the present invention has been described in considerable detail with reference to certain preferred versions thereof, other versions are possible. Therefore, the point and scope of the appended claims should not be limited to the description of the preferred versions contained herein.
As to a further discussion of the manner of usage and operation of the present invention, the same should be apparent from the above description. Accordingly, no further discussion relating to the manner of usage and operation will be provided.
Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. | Composite structural system for floors or roofs comprising steel beams and reinforced concrete slab or shear walls comprising steel columns and reinforced concrete diaphragms. In both cases a steel plate with holes crossed with rebars is welded to the steel beam or to the steel column which performs the integral combination of the concrete, the structural element and the rebars. | 4 |
BACKGROUND OF THE INVENTION
The problems of cleaning marine growth from vessels, and the general type of hull scrubbing device to which the present invention is directed, are illustrated and described in U.S. Pat. Nos. to Campbell, 3,227,124 and Locati, 3,561,391. The Campbell and Locati devices are effective for small craft, but their practical utility is limited to vessels having an 8 to 12 foot beam.
Devices intended for use to clean larger craft are frequently quite elaborate, such, for example as the devices of Romano et al, U.S. Pat. No. 3,859,948, Seiple, U.S. Pat. No. 3,752,109, McLane, U.S. Pat. No. 630,260, Laney, U.S. Pat. No. 3,709,184, and Holland, U.S. Pat. No. 593,298.
One of the objects of this invention is to provide a boat bottom scrubbing device which is simple, but capable of accommodating larger vessels than the device of the Campbell patent, and small vessels as well.
Other objects will become apparent to those skilled in the art in the light of the following description and accompanying drawings.
SUMMARY OF THE INVENTION
In accordance with this invention, generally stated, in a marine vessel bottom cleaning device wherein a floating platform has spaced ways between which a vessel to be cleaned passes lengthwise thereof, and scrubbing means are supported on the platform, at least two elongate scrubbing means are provided spaced from one another lengthwise of the ways, extending in a direction generally athwart the ways and toward one another and in at least one position overlapping one another along the lengthwise path of the vessel, and means are provided for moving the scrubbing means relative to one another from the position at which they overlap one another along the lengthwise path of the vessel in a direction outboard of the vessel and away from one another. In the preferred embodiment, means are provided for translating the entire scrubbing means heightwise of the platform, to accommodate vessels of different draft and also to permit scrubbing of a large area in two passes of the vessel. In the illustrative embodiment described, the means for accomplishing the translation of the scrubbing means toward and away from one another and for the elevation of the scrubbing means include an outside frame, an inside frame which is mounted to move up and down within the outside frame, and a brush support movable transversely on the inside frame.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings, FIG. 1 is a top plan view of one illustrative embodiment of vessel scrubbing device of this invention;
FIG. 2 is a view in side elevation of the device shown in FIG. 1;
FIG. 3 is a sectional view taken along the line 3--3 of FIG. 2; and
FIG. 4 is a sectional view taken along the line 4--4 of FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings for one illustrative embodiment of marine vessel bottom cleaning device of this invention, reference numeral 1 indicates a platform, which includes ways 2, an outside frame 3, an inside frame assembly 4, elongated cylindrical brushes 5 and 6, and auxiliary brushes 7 and 8.
Buoying means, which, in the illustrative embodiment shown, are blocks or sheets of styrofoam 20, are connected to the outside frame 3, to cause the platform to float with the ways 2 above the water level.
In the device shown, the outside frame is in the form of a skeletal box 21 with a substantially horizontal top frame angle 22, outboard vertical rails 23, stanchions 25 and diagonal braces 26. The lower end of each of the diagonal braces 26 is preferably welded both to a vertical rail and to a superstructure connecting beam 30. The connecting beam 30, in this embodiment, is a box beam extending from one outboard edge of the outside frame to the opposite outboard edge of the outside frame, transversely of the platform. Sill beams 31, are welded or otherwise secured between the connecting beams 30, immediately below the stanchions 25, extending fore and aft of the platform.
The stanchions 25 are shown as being substantially square box shapes, and extend vertically, perpendicularly to the connecting beams 30 to which they are secured.
The inside frame assembly 4 includes an inside frame mounted for vertical movement within the confines of the stanchions 25 and above the connecting beams 30 of the outside frame. In this embodiment, one of the members of the inside frame is a brush support 38, which as viewed in FIG. 2 is at the left side of the frame. At the right side of the frame is a sliding inside frame member 60, with an upper cross beam 61, a lower cross beam 62, guide angles 64, which also constitute vertical frame members, and suitable cross bracing to provide the necessary rigidity to the sliding inside frame 60. The inside frame assembly 4 also includes a second, traversing brush support 39.
Both of the brush supports 38 and 39 have an upper cross member 40, a sill beam 41, and vertical rails 42, 43, 44 and 45 extending between, secured to, and spaced along the sill beam 41 and upper cross member 40.
The brush support 38 also includes guide angles 46, which, like the guide angles 64 of the sliding inside frame member 60, have bearing plates 47 and 48 extending the full height of the brush support 38 and sliding frame member respectively.
Inside frame connecting beams 49 extend between the sill beam of the brush support 38 and the sill beam of the sliding inside frame member 60. Suitable gussets or other bracing can be used to add strength to the inside frame structure, but these are conventional and are omitted for clarity.
The traversing brush support 39 has posts 50 defining the outside vertical edges of the brush support. At the foot of the posts 50, the traversing brush support 39 has a carriage 51 secured to it. The carriage 51 extends parallel to the connecting beams 49, and inboard of them. The carriage 51 has revolvably mounted on stub axles projecting outboardly, upper wheels 52 and lower wheels 53. The upper wheels 52 ride on tracks 54 mounted on spacers 55 which are secured to an inside vertical face of connecting beam 49, as shown particularly in FIGS. 1 and 4. The wheels 54 are either in engagement with or closely adjacent the lower edge of the track, to prevent rocking of the carriage. The traversing brush support 39 is accordingly mounted for movement back and forth in a direction athwart the platform and ways.
In this embodiment, the scrubbing means to which the invention is addressed are the brushes 5 and 6. Each of the brushes 5 and 6 has bristles 70 mounted on and for rotation with a shaft 71. The shaft 71 is journalled in bearings trunion mounted between rails 44 and 45. In this embodiment, the shafts 71 are driven by hydraulic motors 74. In the drawings, counterweights 75 are shown as gravity biasing the brushes about a trunion 73. However, this is intended to be somewhat diagrammatic, as indicating any suitable biasing means, which may even take the form of buoyant bristles or a float secured at the end of the bristles most remote from the trunion, for example.
The auxiliary brushes 7 and 8 also include bristles 76, mounted for rotation by shaft 77 driven by a hydraulic motor 78. A counterweight 79, diagrammatically indicated in FIG. 2, serves to bias the brushes about a trunion 80 mounted between rails 42 and 43.
As shown particularly in FIG. 3, pulley blocks or sheaves 92 and 93 are mounted on a top surface of the sill beam 41 of the brush support 38. Similar sheaves are mounted on the sill beam or lower cross beam 62 of the sliding inside frame member. Sheaves 90 and 91 vertically aligned with sheaves 92 and 93 respectively are mounted on the ways 2.
Winches 106, 107, 108 and 109, driven by hydraulic motors, are mounted on the ways. A cable 84 is attached at one end to the drum of the winch 106, passes over the sheave 90, thence around the sheave 92, and is connected at its other end to a sill beam 41 of the brush support 39. A cable 87 is connected at one end to the winch 109, passes over a sheave 90 and around a sheave 92, and is connected to the other side of the sill beam 41 of the brush support 39.
A cable 85 is connected at one end to the winch 107, passes over the sheave 91, around the sheave 93, and is connected at its upper end to an outside frame cross bar between the upper ends of the diagonal braces 26. Similarly, a cable 86 is connected at one end to the winch 108, passes over the sheave 91 around the sheave 93 and is connected at its upper end to an outside frame cross bar between the upper ends of the diagonal braces 26.
A hydraulic pump 81 supplies hydraulic fluid, which it obtains from a hydraulic fluid tank 110, to the hydraulic motors for the winches and the hydraulic motors 74 and 78 which drive the brushes, through suitable piping and flexible conduit.
In the embodiment shown, a pusher sling 115, which consists, in its simplest form, of a cable, is, in the embodiment shown, operated by capstans 116.
In the operation of the device, the sling 115 can be brought around the stern of the vessel, and the vessel pushed to the place at which the bow is adjacent or immediately above the brushes 5 and 6. The inside frame may then be raised until the brushes are in the desired engagement with the bottom of the vessel. The brush support 39 is moved toward or away from the brush support 38 to accommodate the beam of the vessel, this being determined in the embodiment shown, by the bearing of the auxiliary brushes 7 and 8 on the hull. If the position of the auxiliary brushes 7 and 8 is disregarded, it can be seen that for cleaning in a single pass, if the brushes 5 and 6 are ten feet long, a vessel of any beam from one or two feet to twenty feet can be cleaned in one pass, from its center line to a point ten feet outboard of the center line. However, there is little practical limit to the length of the brushes 5 and 6, because, by the use of buoyant bristles or auxiliary floats, as described heretofore, the problem of supporting the brushes is not a difficult one, and by using hydraulic motors to drive them, an extremely high torque can be obtained.
Numerous variations in the construction of the device of this invention within the scope of the appended claims will occur to those skilled in the art in the light of the foregoing disclosure. Merely by way of example, the bearing plates of the guide angles 46 and 64 can be replaced by rollers or bearings, although the bearing plate construction has much to recommend it, in providing a long bearing surface, preventing cocking, and in providing a simple but effective guiding and stabilizing arrangement, kept free from binding by the slight constant movement which is likely to take place when the device is afloat, relative to the stanchions 25 on which they move. The plates do not require as much of an extension, if any, of the fixed frame post, as an arrangement of wheels is likely to require. It will be observed that in the embodiment shown there is no connecting superstructure, so that vessels can be pushed straight through the device. In the case of large vessels, the platform can be pulled through the length of the vessel, rather than having the vessel pushed through the length of the platform, the relative motion being the same. It will be seen that in the diagrammatic representation of the winch and sling system, in order to simplify the portrayal of the scrubbing mechanism, the capstans 116 are shown as being positioned on the entering side of the device. In fact, the capstans will preferably be positioned on the leaving side, so that the sling can push the vessel entirely past the scrubbing brushes.
Other means can be provided for moving the vessel and platform relative to one another. Such devices are suggested by some of the prior art patents to which reference has been made.
Other means for moving the carriage 51 back and forth, and for raising and lowering the inside frame can also be provided, such as a hydraulic piston, or a rack and pinion arrangement.
The scrubbing means are preferably of the revolving brush type but could be of the continuous belt variety such as is suggested by Laney, U.S. Pat. No. 3,709,184, but in any event, the scrubbing means of this invention are staggered, not aligned athwartships.
The buoying means by which the platform is supported can be any suitable means, including air tanks, although the foamed polystyrene blocks have many advantages.
The various beams, bars and posts can be differently constructed. Connecting beam 30, for example, can be a bar-joist type or other trussed member.
The auxiliary brushes can be of other types also, as a "sun flower" type in which the bristles are roughly parallel with the axis of the shaft rather than perpendicular to it. These variations are merely illustrative. | In a marine vessel bottom cleaning device wherein a floating platform has spaced ways between which a vessel to be cleaned passes lengthwise and scrubbing devices are supported on the platform, at least two, elongate scrubbing devices, spaced from one another lengthwise of the ways, extending in a direction generally athwart the ways and toward one another, and in at least one position overlapping one another across the lengthwise path of the vessel, the scrubbing devices being selectively movable relative to one another from the position at which they overlap one another along the lengthwise path of the vessel in a direction outboard of the vessel and away from one another. The entire scrubbing device can be raised and lowered with respect to the platform. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to support devices for securely holding concrete reinforcing rods and wire in a fixed position.
2. Description of the Related Art
In the past support devices for holding reinforcing rods at a particular height in concrete have had several drawbacks. One of the drawbacks has been the inability of the support devices to hold the reinforcing bar at a precise position without it coming out of the support device as forces are placed on the reinforcing bar. It is desired to have a reinforcing bar support device, which can securely hold the reinforcing bar in the support device without it coming out or wiggling around in the support device. The support device should also be stable such that it will not tip over and should have a small footprint at the base.
SUMMARY OF THE INVENTION
The rebar spacer has a rebar holding clip for securely engaging and supporting a rebar and a base portion for supporting the rebar holding clip at a desired height in the concrete form.
The rebar holding clip has a “U” shaped rebar holding portion where the base of the rebar holding portion fits the size and shape of the rebar to securely hold it in place. The clip has arms which will admit the rebar to the clip by bending back out of the way as the rebar is forced downward into the base portion. The arms will then snap back into their normal position to hold the rebar securely in place then the rebar is nested in the “U” shaped base portion of the clip. In this manner the rebar is secured in the clip and cannot be removed by forces placed on the rebar.
The base portion holds the clip at a desired height such that the rebar is placed in the concrete at a known fixed position to maximize its effectiveness in reinforcing the concrete. The base portion may have many different configurations including having a flat base with a large surface area to support the rebar spacer or legs with feet for contacting the ground or walls in which the rebar supports rest. The legs offer a lower footprint at the surface of the concrete for a stronger concrete wall at the surface.
The base portion may have a flat base or legs which should be spread over a large enough area to prevent the rebar spacer from tipping over when holding the rebar, thereby providing a reliable positioning of the rebars.
The height of the base will vary depending on the desired placement of the rebar in the concrete. The higher the base portion the more material and supporting structure there will be and the larger the base will have to be.
The clips may be made for different size rebars and the supporting structure of the base will also be different for the different size loads it is expected to support.
OBJECTS OF THE INVENTION
It is an object of the invention to provide a rebar spacer for holding rebars and wire securely so that they will not come out of the rebar spacer.
It is an object of the invention to provide a rebar spacer for holding rebars and wire at a fixed distance from the base of a concrete form.
It is an object of the invention to provide a rebar spacer with a wide stance so that it will not tip over when holding the rebar.
It is an object of the invention to provide a rebar spacer for quickly and easily securing rebars and wire in the rebar spacer.
It is an object of the invention to provide a rebar spacer with a small footprint.
It is an object of the invention to vary the size of the clips for different size rebars.
It is an object of the invention to vary the height of the clips for different heights of the rebars in a concrete mold.
Other objects, advantages and novel features of the present invention will become apparent from the following description of the preferred embodiments when considered in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front view of the rebar holding clip portion of the rebar spacer.
FIG. 2 is a perspective view of the rebar holding clip portion mounted on a first style base portion of a first height.
FIG. 3 is a top view of the rebar holding clip portion mounted on a first style base portion of a first height.
FIG. 4 is a perspective view of the rebar holding clip portion mounted on a first style base portion of a second height.
FIG. 5 is a top view of the rebar holding clip portion mounted on a first style base portion of a second height.
FIG. 6 is a perspective view of the rebar holding clip portion mounted on a second style base portion.
FIG. 7 is a perspective view of the rebar holding clip portion mounted on a third style base portion of a first height.
FIG. 8 is a top view of the rebar holding clip portion mounted on a third style base portion of a first height.
FIG. 9 is a perspective view of the rebar holding clip portion mounted on a third style base portion of a second height.
FIG. 10 is a front view of the rebar holding clip portion mounted on a third style base portion of a second height.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The rebar holding clip 10 is shown in detail in FIG. 1 . It has a rebar engaging portion 11 which is “U” shaped and has a “U” shaped clip base portion 12 . The rebar holding clip 10 also has two arm supporting columns 13 one on either side of the “U” shaped clip base portion 12 . Each arm supporting columns 13 has a cross member portion 14 for connecting the arm supporting columns 13 to an arm portion 15 angling inward from the arm supporting columns 13 toward the open end of the “U” shaped clip base portion 12 near the center of rebar holding clip 10 .
The arm end 16 of arm portion 15 can traverse angle 19 such that the arm end 16 is opposite plane 17 on the rebar engaging portion 11 . As can be understood from FIG. 1 when rebar 20 is pushed downward between the arm portions 15 , the arm portions 15 are spread apart over angle 19 , allowing the arm to be substantially recessed over the plane 17 , until rebar 20 is admitted into “U” shaped clip base portion 12 . Then arms 15 rebound such that arm ends 16 oppose the top of the rebar 20 locking it inside of the rebar engaging portion 11 of the rebar holding clip 10 .
The arms 15 are designed to have their ends 16 engage the rebar 20 at angles such that the rebar 20 is held snugly in the recess of the clip base portion 12 with the ends of the arms 16 blocking the escape of the rebars 20 by engaging the rebar's circumference.
The plane 17 is angled as shown by angle 18 such that the arm end 16 of arm portions 15 is parallel to the plane 17 when the arm end is opposite the plane 17 .
The rebar holding clip 10 is supported at a fixed height within a concrete form by resting on a base portion. The base portions may be of different styles. In a first embodiment the rebar holding clip 10 is attached to a base portion 30 as shown in FIG. 2 . The base portion 30 has a base 32 , right support wall 34 , a left support wall 36 , and a central support wall 35 for supporting the rebar holding clip 10 a fixed distance above the base 32 . As shown in FIGS. 2 and 3 the right support wall 34 and left support wall 36 and angled inward from the edge of the base 32 to the ends of the rebar holding clip 10 . The central support wall 35 extends vertically from the base 32 to the bottom of the center part of the rebar holding clip 10 .
In a second embodiment as shown in FIG. 4 the rebar holding clip 10 is attached to a base portion 40 as shown in FIG. 4 . The base portion 40 has a base 42 , right support wall 44 , a left support wall 46 , a central support wall 45 and a cross support wall 47 extending between the left wall 46 and the central wall 45 and between the central wall 45 and the right wall 44 , for supporting the rebar holding clip 10 a fixed distance above the base 42 . As shown in FIGS. 4 and 5 the right support wall 44 and left support wall 46 and angled inward from the edge of the base 42 to the ends of the rebar holding clip 10 . The central support wall 45 and the cross support wall 47 extend vertically from the base 42 to the bottom of the center part of the rebar holding clip 10 .
In the second embodiment as shown in FIG. 4 the rebar holding clip 10 is held at a higher position than in the first embodiment as shown in FIG. 2 . The second embodiment therefore may have the cross support wall 47 to hold the rebar 20 without the rebar holding clip 10 bending or twisting on the base portion 40 .
In a third embodiment as shown in FIG. 6 the rebar holding clip 10 is held in place by base portion 60 . Base portion 60 has right angled leg 64 , left angled leg 66 and a vertical central wall 65 . A support beam 67 runs from the left angled leg 66 to the vertical central wall 65 and from the vertical central wall 65 to the right angled leg 64 . The feet 68 on the vertical central wall 65 , the feet 69 on the right and left angled legs 64 , 66 determine the bottom of the base portion 60 without having the large footprint such as the bases 32 and 42 of the embodiments as shown in FIGS. 2 , 3 , 4 and 5 . Having a smaller footprint is advantages for lessening the amount of surface area of the concrete with the base extending therefrom. In some applications the base of the base portion will weaken the surface of the concrete.
In a fourth embodiment as shown in FIGS. 7 and 8 the rebar holding clip 10 is supported by a base portion 70 having feet 71 which may be cone shaped to limit the footprint at the bottom of the base portion 70 . The feet 71 support a base 72 having a left wall 73 and a right wall 74 with a cross wall 77 therebetween resting on the base 72 and connecting the left wall 73 and a right wall 74 to the rebar holding clip 10 which is also resting on the base 72 . The base 72 may have a cut out section 75 to reduce the amount of material used in the base portion 70 and to increase the amount of contiguous concrete for greater strength of the concrete.
The base portion 70 may have four feet 71 one in each corner, or five feet with a central foot 71 directly beneath the center of the base portion under the rebar holding clip 10 to prevent it from sagging in the middle and therefore not supporting the rebar 20 at the proper position.
In a fifth embodiment as shown in FIGS. 9 and 10 the rebar holding clip 10 is supported by the base as shown in FIGS. 7 and 8 but at a higher position. Here the base portion 90 has feet 91 , which may be cone shaped to limit the footprint at the bottom of the base portion 90 . The feet 91 support a base 92 having a left wall 93 and a right wall 94 . The cross wall 97 rests on the base 92 and connects to the rebar holding clip 10 which is supported some distance above base 92 . There may be an opening 98 between the walls 97 and the between the base 92 and the rebar holding clip 10 to reduce the amount of material used in the base portion 90 and to increase the amount of contiguous concrete for greater strength of the concrete. Alternatively the volume shown by opening 98 may be filled by the extension of walls 97 beneath the holding clip portion 10 . The base 92 may have a cut out section 95 to reduce the amount of material used in the base portion 90 and to increase the amount of contiguous concrete for greater strength of the concrete.
In general the rebar holding clip 10 is supported stably at a fixed distance above the base of a concrete form for holding the rebar at a know position such that when the concrete is pored into the mold the rebar will be fixed in place and will not be dislodged from the rebar holding clip. The base portions can be any of a variety of styles of which the above embodiments are a sample.
The rebar spacers may be made from plastics such as polyvinyl chlorides which can be molded in one piece, are strong, light weigh, resilient and low cost.
The bases 32 and 42 in FIGS. 2 and 4 may have legs such as 71 and 91 shown in FIGS. 7 and 9 or other style legs to provide a smaller footprint of the base at the surface of the concrete.
The bases 32 , 42 , 72 , 92 and the feet 71 , 91 or the legs 64 and feet 68 of the rebar spacer should be placed wide enough apart to provide stability such that the rebar spacer will not tip over when a rebar is installed therein.
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. | A rebar spacer having a clip for securely holding a rebar centered in the clip such that the rebar cannot be dislodged from the clip once the clip engages the rebar. The clip is held at a desired height by a base, which will not easily tip over do to a wide stance of the base of the rebar spacer. The rebar spacer will quickly and easily accept the rebar in the clip. The rebar spacers can have a large or small footprint at the surface of the concrete. The rebar spacer can be made of lightweight, durable plastic. The rebar spacer can be molded as one inexpensive piece. The rebar spacer can have a variety of heights and accept a variety of rebar sizes. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a sewing machine having a thread cutting device for severing the free end of the needle thread at the beginning of a sewing operation.
2. Description of the Prior Art
In a conventional sewing machine having a thread cutting device a needle thread and a bobbin thread are severed simultaneously below the throat plate upon completion of a sewing operation. Subsequent to the severing operation the needle and presser foot are both raised to their uppermost positions allowing the workpiece to be withdrawn. The withdrawal of the workpiece will place the free end of the needle thread which extends through the needle eye upon the upper surface of the throat plate.
If the sewing machine is not equipped with a suitable wiper device the free end of the needle thread will be disposed on the upper surface of a subsequent workpiece which is positioned beneath the presser foot and needle and will be held in place thereon during a subsequent sewing operation by means of the presser foot. Thus the free end of the needle thread will be flexibly extended from the upper surface of the workpiece upon completion of a subsequent sewing operation. On the other hand, if the sewing machine is equipped with a wiper device, the free end of the needle thread will be moved aside so as to be offset relative to the presser foot and will be drawn downwardly through the workpiece during the first penetration of the needle in a succeeding sewing operation. The free end of the needle thread below the throat plate is apt to become entangled during the succeeding sewing operation so that the reverse side of the workpiece will be unsightly upon withdrawal of the workpiece after completion of the sewing operation. In order to obviate the foregoing difficulties with the free end of the needle thread it has been necessary to cut off the free end of the needle thread manually so that the workpiece will be neat and attractive.
SUMMARY OF THE INVENTION
It is therefore one of the objects of the present invention to provide a sewing machine having a thread cutting device which will operate automatically to obviate the aforementioned difficulties.
It is another object of the present invention to provide a sewing machine having a thread cutting device for automatically cutting off the free end of the needle thread at the beginning of a subsequent sewing operation.
It is still another object of the present invention to provide a sewing machine having a thread cutting device comprised of a cutter element mounted on the presser bar of the sewing machine and having an offset leg portion extending transversely across the presser foot behind the needle of the sewing machine, cutting means on the side of said offset leg portion remote from said needle and means for oscillating said cutter element upon raising and lowering of said presser bar for shifting the free end of a needle thread extending through the needle eye from a position between said offset leg portion and said needle to a position adjacent said cutting surface.
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.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front elevation view, partly in section, of a first embodiment of the present invention.
FIG. 2 is an enlarged front elevation view of the portion in FIG. 1 within the circle A.
FIG. 3 is an enlarged side elevation view of the sewing machine as shown in FIG. 1 taken in the direction of the arrow B.
FIG. 4 is a rear elevation view of a sewing machine shown in FIG. 3 as viewed in the direction of the arrow C.
FIGS. 5 and 6 are rear views similar to FIG. 4 showing the presser foot in raised position when raised by lever 35 and linkage 23, respectively.
FIGS. 7 and 8 are enlarged perspective views of the presser foot and cutter element showing the different positions of the cutter element relative to the presser foot.
FIG. 9 is a partial side elevation view of a second embodiment of the present invention.
FIG. 10 is a partial front elevation view of the sewing machine of FIG. 9 as seen in the direction of the arrow D.
FIG. 11 is a cross-sectional view taken along the line XI--XI of FIG. 10.
FIG. 12 is a partial side elevation view of a sewing machine according to a third embodiment of the present invention.
FIG. 13 is a partial front view of the sewing machine of FIG. 12 as viewed in the direction of the arrow E.
FIGS. 14, 15, 16 and 17 are detailed perspective views of the presser foot and cutter element showing the operation of the sewing machine according to the third embodiment in sequential views.
FIG. 18 is a cross-sectional view taken along the line XIV--XIV of FIG. 14.
DETAILED DESCRIPTION OF THE INVENTION
Referring first to the embodiment of FIGS. 1-8, a sewing machine 10 is shown in FIG. 1 comprised of a bed 15 including a throat plate 16 and an overhanging arm 17 terminating in a head 18 disposed in spaced relation above the bed 15. A presser foot 21 is secured to the lower end of a presser bar 20 which may be raised and lowered by means of the mechanism 22 which is controlled by the knee operated linkage 23. The needle bar, needle and associated operating mechanism have not been illustrated in FIG. 1 for the sake of clarity. The thread cutting device 11 according to the present invention is located within the circle A and is shown in greater detail in FIGS. 2-8.
As shown in FIG. 2, a needle bar 19 is mounted for vertical recipricatory movement within the head 18 and a needle 14 having an eye 13 is secured to the lower end thereof. The presser bar 20 is located rearwardly of the needle bar 19 and the needle is operable within the forwardly open slot in the presser foot 21. The presser foot 21 may be raised and lowered by means of a mechanism 22, 23 shown in FIG. 1 or by the lever 35 shown in FIGS. 4 and 5. The details of the arrangement for raising and lowering the presser foot are old and well known in the art and a detailed explanation thereof is not deemed necessary.
With respect to the needle thread cutting device according to the present invention a bracket 24 is secured to the presser bar 20 by means of a screw 25. The bracket 24 supports a tubular sleeve portion 26, the axis of which is parallel to the feed direction of the sewing machine. A shaft 27 is rotatably disposed within the sleeve portion 26 and is provided with an enlarged portion 28 at one end thereof. The enlarged portion 28 of the shaft 27 is disposed in abutment with one end of the sleeve portion 26. The shaft 27 extends through a collar 29 and a lower slot 30 in the guide plate 31 and the shaft 36 upon which lever 35 is mounted extends through an upper slot 37 to movably support plate 31 on the head 18. The collar 29 is secured to the shaft 27 by means of screw 32 and a snap ring 33 is secured in a groove at the other end of the shaft 27 on the opposite side of the guide plate 31 from the collar 29. Thus the shaft 27 is prevented from axial movement within the sleeve 26 while the left hand of the shaft 27 as viewed in FIG. 3 is disposed in sliding engagement with a lower slot 30 of the guide plate 31.
A stop tab 34 is located in the middle portion of the guide plate 31 and is formed by cutting and bending the piece of the guide plate out of the plane thereof. The stop tab 34 is located in closely spaced relationship to the free end of the presser bar control lever 35 when the lever 35 and the guide plate 31 are disposed in the position shown in FIG. 4. A pair of closely spaced pins 40 and 41 are secured to the guide plate below and forwardly of the stop tab 34 and protrude from the guide plate 31 in the opposite direction from the stop tab 34. An actuator member 42 formed of stiff wire is provided for imparting a rotational movement to the shaft 27. One end of the actuator member is slidably disposed between the pins 40 and 41 and is provided with two oppositely directed bends which will act as a cam follower portion. The other end portion 42b of the actuator member 42 is secured in a secant hole 43 in the collar 29 by means of a set screw 44. The middle portion 42c of the wire actuator member 42 is provided with a single loop to impart a resilient flexibility to the member.
A cutter element 45 of stiff wire has one end thereof secured in an aperture in the enlarged portion 28 of the shaft 27 by means of a set screw 60. The other end of the cutter element 45 is bent to form a hook 46 having an end edge 47 and a curved middle portion formed with a blade for a sharp edge 49 at the rear portion thereof facing toward the presser foot bar. The hooked portion 46 is normally disposed immediately above the presser foot to the rear and to one side of the needle 14 as best seen in FIGS. 2 and 3.
A conventional thread cutting device 50 (FIG. 1) is located below the throat plate 16 to cut the needle thread 12 and a bobbin thread (not shown) simultaneously on completion of a sewing operation. Such cutting devices are old and well known in the art and the construction and operation need not be described in the present application. In the operation of the needle thread cutting device 11 according to the present invention the needle 14 is raised to its uppermost position upon completion of the sewing operation and the subsequent severing of the needle thread and bobbin thread below the throat plate by the cutting device 50. The presser foot 21 is then moved upwardly by actuation of the presser foot lifter linkage 23 prior to the withdrawal of the workpiece W while the presser bar control lever 35 is left in the position shown in FIG. 4. The lifting of the presser bar 20 along with the presser foot 21 causes the shaft 27 to move upwardly in the slot 30 in the guide plate 31 since the guide plate 31 will be maintained in its lowest position by means of the stop tab 34 engaging the free end of the lever 35 as seen in FIG. 6. Since the guide plate 31 is held stationary the pins 40 and 41 will also remain stationary so that upward movement of the shaft 27 and the collar 29 will cause the bent portion 42a of the actuator member to move upwardly between the pins 40 and 41. The cam function created by the bends in the member 42 will cause the member 42 to rotate the shaft 27 and thereby swing the thread cutting device 45 from the position shown in FIG. 4 to the position shown in FIG. 6. During this movement of the thread cutting device 45 the needle thread 12 is momentarily displaced in the forward direction by the end edge 47 of the hook portion 46 as the hook portion moves from the solid line position to the phantom position shown in FIG. 7. Thereafter when the workpiece is drawn away from the stitch forming area the free end of the needle thread 12 will be drawn up through the needle hole to rest upon the upper surface of the thread plate 16.
When a new workpiece is inserted between the throat plate 16 and the presser foot 21 prior to initiating a new sewing operation the free end of the needle thread 12 will then rest upon the upper surface of the new workpiece. Upon lowering of the presser bar 20 the new workpiece and the needle thread 12 will be clamped against the throat plate 16. The downward movement of the presser bar 20 also lowers the member 42 and the thread cutting device 45 will be returned to its original position as shown in FIG. 8 with the needle thread 12 disposed in engagement with the cutting edge 49. As soon as the new sewing operation is commenced the free end of the needle thread will be cut off by the cutting device 49 since the free end of the needle thread 12 is being held by the presser foot 21 while the needle thread is tensioned by the stitch forming operation. Thus the severed end of the needle thread 12 will not become entangled by being drawn below the throat plate 16 during subsequent stitching operations. Also since the needle thread is cut fairly close to the workpiece a long flexible length of needle thread will not protrude from the upper surface of the finished work product.
When it is not necessary or desirable to cut off the free end of the needle thread the presser bar 20 may be lifted by the control lever 35 in lieu of the linkage 23. A pin 39 extends from the guide plate 31 on the same side as the stop tab 34 and is located above and to one side of the upper slot 37 in the guide plate 31. Thus when the control lever 35 is moved from the position shown in FIG. 4 to the position shown in FIG. 5 the lever will engage the pin 39 and since the free end of the lever 35 is no longer disposed adjacent the stop tab 34 the entire guide plate 31 will be raised along with the presser bar 20. Thus the member 42 will not move between the guide pins 40 and 41 to produce any camming action and therefore the thread cutter 45 will not be oscillated.
In the embodiment of FIGS. 9-11, the thread cutter 145 is formed of sheet metal instead of wire and the upper end of the thread cutter is secured in a vertical slot in the end of the enlarged portion 128 of shaft 127 by means of a set screw 160. The lower end portion of the thread cutter 145 is formed into a hooked portion 146 having an end edge 147 and a middle portion 148. The middle portion 148 is disposed at right angles to the feeding direction and is located rearwardly of the needle 114. The end edge 147 is forwardly inclined so as to engage and momentarily displace the needle thread 112 forwardly as the thread cutter 145 moves to the right as viewed in FIG. 11. A V-shaped cutting blade 149 is provided in the rear edge of the middle portion 146 so that upon return of the thread cutter arm 145 the needle thread will be moved rearwardly by the portion 145 into the V-shaped blade portion for subsequent severing upon the initiation of a new stitch forming operation. The oscillation of the thread cutter arm 145 is accomplished in the same manner as discussed in the previous embodiment.
In the embodiment shown in FIGS. 12-18, the sewing machine 210 is provided with a head 216 having a needle bar 219 and a presser bar 220 mounted therein for vertical reciprocation. A needle 214 is secured to the end of the needle bar 219 and a presser foot 221 is pivotally mounted on the end of the presser bar 220. The presser bar 220 may be raised and lowered by means of a hand lever 235 as is well known in the art. The details of the needle bar drive and the connection for raising and lowering the presser bar are not shown since they are also considered to be old and well known in the art.
A bracket 224 is secured by means of a screw 225 to the presser bar 220. The bracket 224 is provided with a tubular sleeve portion 226 the axis of which is disposed parallel to the feeding direction of the fabric beneath the presser foot 221. A shaft 227 having an enlarged end portion 228 is rotatably disposed within the sleeve portion 226. The enlarged portion 228 is disposed in abutment with one end of the sleeve 226. The hub portion 251 of a lever 252 is secured to the opposite end of the shaft 227 by means of a set screw 255 in spaced relation to the sleeve portion 226. A torsion spring 259 is disposed about the shaft 227 and is connected at opposite ends to the hub portion 251 of the lever 252 and the sleeve portion 226 in a manner to normally bias the lever 252 in the clockwise direction as viewed in FIG. 13.
A rotary solenoid 255 is secured to the rear side of the head 216 by means of a bracket 254. The rotary solenoid 255 has an axle 256 which is designed to be rotated clockwise as viewed in FIG. 13 upon energization of the rotary solenoid 255 and which is free to return to its original position upon de-energization of the rotary solenoid 255. One end of a lever 257 is secured to the end of the solenoid axle by means of a set screw 258. The other end portion of the lever 257 is disposed approximately at right angles to the throat plate 216 in engagement with the free end portion of the lever 252. Thus upon energization of the solenoid 255 the clockwise movement of the lever 257 will rotate the shaft 227 in the counter-clockwise direction due to engagement with the lever 252. When the solenoid is de-energized the torsion spring 259 will return the levers 252 and 257 to the positions shown in FIG. 13. One end of the thread cutter 245 extends through an opening in the enlarged shaft portion 228 and is secured therein by means of a set screw 260. The other end portion of the cutter 245 is formed into a hook 246 having an end edge 247 and a middle portion 248 having a blade edge 249 provided on the rear edge thereof. The hook portion 246 of the cutter 245 is located between the presser foot 221 and the needle 214 with the middle portion being disposed at approximately right angles to the direction of feed of the sewing machine. The end edge 247 of the hook portion 246 is so formed that the needle thread 212 depending from the needle eye 213 of the needle 214 may be momentarily displaced forwardly by the edge 247 in the course of movement of the thread cutter to the right as viewed in FIG. 14 and will be caught by the hooked portion 246 during movement to the left as viewed in FIG. 15. In other words, the needle thread 12 is displaced from the front of the hooked portion 246 to the rear of the hooked portion 246 during the oscillatory movement of the thread cutter 245.
As in the previous embodiment a thread cutting device 250 is installed below the throat plate 216 so as to cut the needle thread 212 and a bobbin thread (not shown) simultaneously upon completion of a sewing operation. Thereafter the needle 214 is moved upwardly to its fully raised position and the rotary solenoid 255 is energized to turn. As a result of the energization of the rotary solenoid 255 the lever 257 is rotated clockwise as viewed in FIG. 13 to rotate the lever 252 counter-clockwise against the force of the torsion spring 259. Therefore, the thread cutter 245 will be moved from the solid line position to the phantom line position as shown in FIG. 14. As mentioned above, this movement of the thread cutter device 245 will cause the needle thread 212 to be momentarily displaced in the forward direction by the end edge 247 but the thread 212 will be returned to the original position as soon as the thread cutter device 245 reaches the phantom line position of FIG. 14. Thereafter in the course of the return movement of the thread cutter device 245 to the original position as shown shown in FIG. 15 upon de-energization of the rotary solenoid the thread 212 will be captured by the hook portion 246. After the presser foot 221 is raised by actuation of the lever 235 the workpiece can be withdrawn and the free end of the needle thread will then rest upon the upper surface of the thread plate 216. Thereafter when a new workpiece is inserted between the throat plate 216 and the presser foot 221 the free end of the needle thread 212 will then rest on the new workpiece. Upon lowering of the presser foot 221 the free end of the needle thread and the new workpiece will be held against the throat plate 216 as shown in FIG. 16. Upon starting of the sewing operation the free end of the needle thread 212 will be cut off by the blade 249 since the needle thread 212 will be tensioned between the presser foot 221 and the stitch forming mechanism as shown in FIG. 17. Thus the free end of the needle thread will not be drawn beneath the throat plate during succeeding sewing operations nor will the elongated flexible thread end protrude from the upper surface of the workpiece to spoil the appearance thereof.
Although the cutting blade has been provided on the rear side of the middle portion in each of the embodiments it is also possible to locate the cutting blade on the forward side of the middle portion as long as the thread cutting device is maintained in proper adjustment relative to the needle so that the needle thread will not be cut during a sewing operation.
While the invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those in the art that the foregoing and other changes in form and details may be made therein without departing from the spirit and scope of the invention. | A sewing machine is provided with a needle thread cutting device for severing the free end of the needle thread extending through the eye of the needle at the beginning of a sewing operation to prevent entanglement of the free end with the stitches being formed. A cutter element is mounted for oscillating movement in conjunction with the raising and lowering of the presser foot. The lower end of the cutter element is provided with a transverse leg extending across the upper surface of the presser foot in close proximity thereto rearwardly of the needle. The transverse leg portion is provided with a cutting edge on the side thereof remote from the needle. Subsequent to a previous sewing operation the raising and lowering of the presser foot will oscillate the cutter element to move the leg portion from a position behind the needle thread to a position in front of the needle thread so that upon initiation of a new stitching operation the free end of the needle thread will be severed relatively close to the first stitch. | 3 |
BACKGROUND OF THE DISCLOSURE
a. Field of Invention
This invention relates to a process for the optical resolution of the racemic organic bases, (±)-(4a,13b-trans)-(3-hydroxy,13b-trans)-3-isopropyl-2,3,4,4a,8,9,13b,14-octahydro-1H-benzo[6,7]cyclohepta[1,2,3-de]-pyrido[2,1-a]isoquinolin-3-ol and (±)-(4a,13b-trans)-(3-hydroxy,13b-trans)-3-tert-butyl-2,3,4,4a,8,9,13b,14-octahydro-1H-benzo[6,7]cyclohepta[1,2,3-de]pyrido[2,1-a]isoquinolin-3-ol into their corresponding (+)-enantiomers.
B. Prior Art
For convenience, (4a,13b-trans)-(3-hydroxy,13b-trans)-3-isopropyl-2,3,4,4a,8,9,13b,14-octahydro-1H-benzo[6,7]cyclohepta[1,2,3-de]-pyrido[2,1-a]isoquinolin-3-ol is hereafter designated as Compound I and (4a,13b-trans)-(3-hydroxy,13b-trans)-3-tert-butyl-2,3,4,4a,8,9,13b,14-octahydro-1H-benzo[6,7]cyclohepta[1,2,3-de]pyrido[2,1-a]isoquinolin-3-ol is hereafter designated as Compound II.
Compounds I and II are neuroleptic agents with essentially all the activity residing in the (+)-optically active enantiomer. The racemic form of Compound II is known generically as "butaclamol", see L. G. Humber and F. Bruderlein, Abstracts of Papers of the 167th Am. Chem. Soc. Meeting, Los Angeles, California, Division of Medicinal Chemistry, Paper No. 5; Apr. 1-5, 1974; and K. Voith, ibid (Paper No. 6). The (+)-form of Compound I is known generically as "dexclamol". The preparation of the racemic mixture of Compounds I and II is described in U.S. Pat. No. 3,914,305, issued Oct. 21, 1975 and U.S. Pat. No. 3,852,452 issued Dec. 3, 1974; see also Belgian Pat. No. 762,595, issued Aug. 5, 1971. In these Patents Compounds I and II are recited as 5-isopropyl-and 5-tert-butyl-1,4,5,6,6a,10,11,15-b-octahydro-3H-benzo[6,7]cyclohepta[1,2,3-de]pyrido[2,1-a]isoquinolin-5-ol (Isomer A), respectively. Compounds I and II are described in U.S. patent application U.S. No. 518,853, filed Oct. 29, 1974, now U.S. Pat. No. 3,985,751.
Prior to the present disclosure the resolution of racemic organic bases was usually performed by procedures requiring several steps of multiple recrystallizations. Because of time and expense required for such procedures, the need for an efficient resolution of the above noted racemic organic bases, Compounds I and II, is highly desirable.
Accordingly, a process is described here which avoids multiple recrystallizations and resolves the above noted bases in a commercially feasible operation and in high yield.
DESCRIPTION OF THE INVENTION
The process for resolving racemic Compound I and Compound II comprises: dissolving one part by weight of a racemic mixture of the Compound I or Compound II and 1.0 to 1.3 parts by weight of L-(+)-tartaric acid in 4 to 6 parts by volume of methanol at 20° to 40° C: diluting the solution with 1 to 3 parts by volume of acetone or ether at 15° to 25° C to crystallize the corresponding L-(+)-tartrate of the (+) enantiomer of the compound; dissolving one part by weight of the L-(+)-tartrate in a mixture of 5 to 8 parts by volume of water and 5 to 8 parts by volume of a water-immiscible organic solvent containing 5 to 10 parts by weight of alkali; separating the water-immiscible solvent from the aqueous phase; isolating the corresponding (+)-enantiomer free base from the water immiscible solvent; and if desired converting said (+)-enantiomer free base into its corresponding pharmaceutically acceptable salt.
Preferred water-immiscible organic solvents for the process include toluene and benzene.
Respecting the alkali, any alkali may be used for the present process provided that it will render basic the aqueous phase and cleave the L-(+)-tartrate of the (+)-enantiomer and cause the (+)-enantiomer free base to go into the water-immiscible solvent. Preferred alkalies for this purpose include ammonium hydroxide, the alkali metal hydroxides, for example, sodium or potassium hydroxide, the alkaline earth hydroxides, for example, calcium or magnesium hydroxide, or sodium or potassium carbonate.
Noteworthy about the present process is that fact that the L-(+)-tartrate of the (+)-enantiomer of the compound of formula I is obtained pure by direct crystallization from the first step of this process and that further purification of this salt by recrystallization is not required. Furthermore, if the (+)-enantiomer free base is converted to a pharmaceutically acceptable salt, preferably the hydrochloride, one recrystallization of the latter salt is sufficient to obtain the pure, pharmaceutically acceptable salt of the (+)-enantiomer. All these features avoid the expensive and tedious operations of purification procedure usually required for resolution and serve to promote the efficiency of the present process.
The following example illustrates further this invention.
EXAMPLE I
a. Resolution
Racemic Compound I hydrochloride (2890 g., 7.52 mole) is suspended in toluene (14.5 l., 5 parts) and converted to its corresponding free base by stirring with concentrated ammonium hydroxide (1170 ml., 1.2 equivalents) and water (585 ml.). The clear aqueous phase is discarded. The toluene layer is washed with water (1170 ml.), dried over sodium sulfate and concentrated under reduced pressure to give the free base of racemic Compound I as a thick oil. The oil is dissolved in methanol (11.6 l., 4 parts) at 40° C, solid L-(+)-tartaric acid (1.13 kg., 7.52 mole) is added and the mixture is stirred until a solution is obtained. The solution is diluted with acetone (2890 ml., 1 part) and allowed to crystallize for 1 hour. More acetone (2890 ml., 1 part) is added. The mixture is cooled to 20° C and stirred for another hour. The crystals are collected by filtration and washed with methanol-acetone 50/50 (2 × 2.17 l.) and then with acetone (2.17 1.). The L-(+)-tartrate of the (+)-enantiomer of Compound I thus obtained forms pale straw coarse crystals, 870 g. air-dried (crop A, 46.4% of the theoretical amount of the (+)-enantiomer tartrate), m.p. 180° -187° C (decompn.), [α] D 25 = +200° (c = 1% in methanol). The mother liquor from the crystallization is processed as described in section (b) hereinafter.
b. Recycling of material recovered from the mother liquor
The mother liquor from section (a) is concentrated to a small volume. Toluene (16.1) is added and the tartrate salt is converted to the free base by stirring with concentrated ammonium hydroxide (2 l.) and water (2 l.). The clear aqueous phase is discarded. The toluene layer is washed with water (2 l.), dried over sodium sulfate and evaporated under reduced pressure. The residual oil (about 3.7 kg., containing theoretically 2.04 kg. of base) is dissolved in isopropanol (5 parts, 10 l.), heated to 50° C and concentrated hydrochloric acid (560 ml.) is added in one portion. The crystals of racemic Compound I hydrochloride separate almost immediately. The mixture is stirred for 30 minutes at 55° C. Acetone (2 parts, 4.0 l.) is added and the mixture cooled to 20° C over a period of 90 minutes, the crystals are collected by filtration, washed with isopropanol-acetone (5:2. 2.0 1.) and sucked as dry as possible. The wet cake is removed from the filter, slurried in the latter solvent mixture (3.7 l.), filtered and washed with acetone (1.86 l.). The acetone-wet cake of the racemic Compound I hydrochloride (wet weight 2.4 kg.) is used without drying for subsequent resolution as described above. Dry weight estimated by drying of an aliquot is 1240 g., [α] D 25 = -2°, (c = 1% in methanol), m.p. 266.5° -268° C (decomp.).
The mother liquor which contains the (-)-enantiomer is discarded. The racemic hydrochloride, obtained above, is converted to its free base and subjected to the resolution procedure as described in section (a). From 1240 g. of the (±)-hydrochloride 385 g. of the L-(+)-tartrate of the (+)-enantiomer are obtained, called crop B, (m.p. 179°-187° C decomp.), [α] D 25 = +199° (c = 1% in methanol).
The mother liquor from the preceding recycling procedure is subjected to a further recycling. Thus crop C (161 g.) of the L-(+)-tartrate of the (+)-enantiomer is obtained m.p. 178 -183.5° C (decompn.) [α] D 25 = +203° (c = 1% in methanol).
The mother liquor from the second recycling procedure is subjected to a further recycling procedure giving crop D (64 g.) of the L-(+)-tartrate of the (+)-enantiomer, m.p. 179.5°-185° C (decompn.) [α] D 25 = +202° (c = 1% in methanol).
Total yield of the L-(+)-tartrate of the (+)-enantiomer of Compound I (crops A+B+C+D) is 1480 g. (870 g. + 385 g. + 161 g. + 64 g. respectively), which is 93% of the theoretical yield. The four crops are combined and converted directly without further purification to the (+)-hydrochloride as follows.
c. Conversion of the L-(+)-tartrate of the (+)-enantiomer of Compound I to the corresponding (+)-enantiomer hydrochloride
The combined L-(+)-tartrate fractions of the (+)-enantiomer (1480 g., 1.75 mole) are suspended in toluene (6 parts, 8.9 l.) and converted to the corresponding free base by stirring with concentrated ammonium hydroxide (910 ml., 7 mole) and water (910 ml.). The clear aqueous phase is discarded. The toluene solution is washed with water (910 ml.), dried over sodium sulfate and evaporated under reduced pressure to dryness. The residual oil is dissolved in methylene chloride (3 parts, 4.5 l.) and hydrogen chloride is passed into the stirred solution until the solution has pH2. The solvent is evaporated under reduced pressure removing in part excess hydrogen chloride. The residual oil is redissolved in methylene chloride (3 parts, 4.5 l.) and the solution is diluted at reflux temperature with ethyl acetate (3 parts, 4.5 l.). Methylene chloride (2.25 l., 1.5 parts) is removed by distillation at atmospheric pressure (bath temperature, 67°-70° C). The mixture is cooled to room temperature, stirred for an additional hour and crystals are collected by filtration. The cake is washed with 30% methylene chloride in ethyl acetate (2 × 740 ml.) and with ethyl acetate (740 ml.). The (+)-enantiomer hydrochloride obtained weighs 1180 g. (air-dried, 87.5%) m.p. 241°-241.5° C (decompn.), [α] D 25 = +213° (c = 1% in methanol).
d. Final purification of Compound I (+)-enantiomer hydrochloride
The (+)-enantiomer hydrochloride, obtained above (1180 g.), is dissolved in 2.5 parts methylene chloride (2.95 1.) and charcoal (Nuchar) (60 g., 5%) is added to the solution. The mixture is stirred for 10 minutes and filtered through diatomaceous earth (Celite). The filter pad of diatomaceous earth is washed with methylene chloride (590 ml.). The filtrate is heated to reflux and ethyl acetate (2.36 l.) is added slowly in such a way that it mixes with methylene chloride returning from a condenser of the reflux system in order to prevent precipitation of oily product (30 minutes). The solution is seeded and about 1200 ml. of methylene chloride is removed by distillation at atmospheric pressure while the product crystallizes. The mixture is cooled to room temperature and stirred for an additional hour. The crystals are collected by filtration, washed with 30% methylene chloride in ethyl acetate (2 × 590 ml.) and with ethyl acetate (590 ml.). The pure (+)-enantiomer hydrochloride of compound I is dried for 5 hours at 60° C in a vacuum oven. Yield: 1070 g. (90.6% for the purification), m.p. 241° C (decompn.), [α] D 25 = +215° (c = 1% in methanol).
In the same manner Compound II is resolved into its corresponding (+)-enantiomer, the corresponding hydrochloride of the (+)-enantiomer having m.p. 288°-291° C, [α] D 25 = +218.5° (c = 1% in methanol). | An efficient, commercially feasible process for the resolution of the organic bases, (±)-(4a,13b-trans)-(3-hydroxy,13b-trans)-3-isopropyl-2,3,4,4a,8,9,13b,14-octahydro-1H-benzo[6,7]cyclohepta[1,2,-3-de)pyrido[2,1-a]isoquinolin-3-ol and (±)-(4a,13b-trans)-(3-hydroxy,13b-trans)-3-tert-butyl-2,3,4,4a,8,9,13b,14-octahydro-1H-benzo[6,7]cyclohepta[1,2,3-de]pyrido[2,1-a]isoquinolin-3-ol, known neuroleptic agents, is disclosed. The process comprises resolving the racemic organic bases with L-(+)-tartaric acid to obtain directly the pure L-(+) tartrate of the (+)-enantiomer and converting the latter salt to the corresponding (+)-enantiomer free base. | 2 |
STATEMENT OF GOVERNMENT INTEREST
This invention was made with Government support under Contract No.: HR0011-09-C-0002 (Defense Advanced Research Projects Agency (DARPA)). The Government has certain rights in this invention.
BACKGROUND OF THE INVENTION
This invention generally relates to integrated circuits having charge-recycling stacked voltage domains. More specifically, the invention relates to calibration schemes for such stacked voltage domains.
In the design and operation of integrated circuits, power consumption is a major concern. As a result of the devices on the circuits becoming smaller and of the higher performance requirements for the circuits, the circuits, or chips, are consuming more power, and the voltage levels supplied to the circuits are being reduced. This leads to a significant growth in the currents needed to operate the devices on the circuits.
In on-chip and inter-chip data communication systems where high data bandwidth is required, power dissipation and I/O area are very crucial. For instance, in modern multi-core microprocessors, processor cores and caches are connected by data buses having thousands of bits. In high-performance servers, the inter-chip links from processors to network switches or off-chip cache also require I/O buses hundreds of bits wide running at multiple Gb/s per lane data rates. Compact and low-power I/O schemes are needed for these high-performance systems. Among various circuit blocks in an I/O system, the signaling power dissipated on the channel consumes a big part of the overall I/O power. Since the signaling power is proportional to the square of the voltage swing transmitted on the channel, it is well known that reducing the signal swing will lower the signaling power.
Charge-recycling techniques have been presented to achieve reduced signal swing by stacking circuits with regular and predictable data switching activities, such as logic circuits [S. Rajapandian et al., “High-Voltage Power Delivery Through Charge Recycling”, JSSC, pp. 1400-1410, June 2006] or clocking circuits [R. Inti et al., “Intergraded Regulation for Energy-Efficient Digital Circuits”, ISSCC, pp. 152-153, February 2011]. Charge-recycling stacked low-swing I/O is also disclosed in U.S. Patent Application Publication No. 2011/0298440, the disclosure of which is hereby incorporated herein by reference. In charge-recycling stacked logic domains, two groups of drivers are logically stacked between the supply voltage and ground.
Since the voltage regulator provides regulation function only when there is current mismatch between the top and bottom driver groups, the on-chip voltage regulator can be very compact and highly efficient. Due to its high area and power efficiency, the charge-recycling stacked I/O scheme can be well suited for a variety of applications, including on-chip signaling, across-chip signaling in 3D chip stack and local chip-to-chip signaling through silicon carrier or other benign channels.
However, the I/O performance can be adversely affected due to chip process variations, supply voltage fluctuations and temperature deviations along the I/O bus. The charge-recycling stacked I/O should be robust against PVT variations, i.e., process, voltage and temperature variations. Appropriate calibration approaches are needed to achieve this robust I/O performance over different operating conditions.
BRIEF SUMMARY
Embodiments of the invention provide a method and system for calibrating a mid-voltage node in an integrated circuit including an input-output circuit having charge-recycling stacked voltage domains including at least first and second voltage domains. In one embodiment, the method comprises transmitting data through the input-output circuit, including transmitting a first portion of the data across the first voltage domain, and transmitting a second portion of the data across the second voltage domain. The method further comprises measuring a specified characteristic of the data transmitted through the input-output circuit; and based on the measured specified characteristic, adjusting a voltage of said mid-voltage node to a defined value.
In an embodiment, the input-output circuit includes a plurality of receivers; each of the voltage domains includes a plurality of transmit drivers; and in each of the voltage domains, each of the transmit drivers of the voltage domain transmits data to one of the receivers of the input-output circuit. The specified characteristic of the data is measured by measuring a specified performance characteristic of the data transmitted by one of the transmit drivers or of the data received by one of the receivers.
In one embodiment, the transmit drivers of the first voltage domain have variable strengths, and the voltage of said mid-voltage node is adjusted by adjusting the strength of at least one of the transmit drivers of the first voltage domain.
In an embodiment, the transmit drivers of the first voltage domain transmit data to a first group of the receivers, and the specified characteristic of the data is measured by monitoring an accuracy at which the first group of the receivers receive the data from the transmit drivers of the first voltage domain. The voltage of the mid-voltage node is adjusted by adjusting the strengths of the drivers of the first voltage domain, based on the monitored accuracy at which the first group of the receivers receive the data from the transmit drivers of the first voltage domain, to adjust the voltage of the mid-voltage node.
In one embodiment, the accuracy at which the first group of the receivers receive the data from the transmit drivers of the first voltage domain is monitored by detecting a size of a specified data eye for the first group of the receivers, in which the first group of the receivers accurately receive the data transmitted to the first group of the receivers from the transmit drivers of the first voltage domain. The strengths of the transmit drivers of the first voltage domain are adjusted by adjusting the strengths of the drivers of the first voltage domain based on the size of the specified data eye.
In an embodiment, procedure for adjusting the strengths of the drivers of the first voltage domain includes determining a size of a specified data eye for the first group of the receivers using predetermined values for specified parameters of the input-output circuit, and comparing the size of the detected data eye and the size of the determined data eye. When the size of the detected data eye is larger than the size of the determined data eye, the strengths of the drivers of the first voltage domain is reduced; and when the size of the detected data eye is smaller than the size of the determined data eye, the strengths of the drivers of the first voltage domain is increased.
In one embodiment, the specified characteristic is a given performance characteristic of both the first and second voltage domains, and the voltage of the mid-voltage node is adjusted until this given performance characteristic of both the first and second voltage domains are equal.
In an embodiment, each of the first and second voltage domains includes a plurality of drivers, the input-output circuit includes a plurality of receivers, the transmit drivers of the first voltage domain transmit data to a first group of the receivers, and the transmit drivers of the second voltage domain transmit data to a second group of the receivers. In an embodiment, the given performance characteristic of both the first and second voltage domains is measured by measuring a given performance characteristic of the first and second groups of the receivers, and the voltage of the mid-voltage node is adjusted until the given performance characteristic of the first and second groups of the receivers are equal.
In one embodiment, the drivers of the first voltage domain have variable strengths, and the voltage of the mid-voltage node is adjusted by adjusting the strengths of the drivers of the first voltage domain until the given performance characteristic of the first and second groups of the receivers are equal.
In one embodiment, the integrated circuit further include a supply voltage and a lower voltage for the first and second voltage domains, the first and second voltage domains are located electrically in series between said supply voltage and said lower voltage, and
the mid-voltage node is located electrically in series between the first and second voltage domains.
In one embodiment, the method comprises transmitting data across the first and second voltage domains, and adjusting a voltage of said mid-voltage node to a defined value to obtain voltage drops across the first and second voltage domains. In an embodiment, each of the voltage domains includes a plurality of transmit drivers having variable strengths, and the voltage of the mid-voltage node is adjusted by adjusting the strength of at least one of the transit drivers of one of the voltage domains to adjust the voltage of the mid-voltage node to said defined value.
In an embodiment, each of the transmit drivers includes a plurality of transistors having on and off states, and the strength of at least one of the transmit drivers is adjusted by switching one or more of the transistors of said at least one of the transmit drivers between the off state and the on state.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 illustrates a charge-recycling stacked voltage domain.
FIG. 2 is a circuit diagram showing a calibration scheme, in accordance with an embodiment of the invention, for the charge-recycling stacked voltage domain of FIG. 1 .
FIG. 3 depicts an open-loop calibration scheme for the charge-recycling stacked voltage domains, in accordance with an embodiment of the invention.
FIG. 4 shows a further, load-aware calibration scheme for the charge-recycling stacked logic domain, in accordance with an embodiment of the invention.
FIG. 5 illustrates a receiver-aware driver calibration scheme, in accordance with an embodiment of the invention.
DETAILED DESCRIPTION
Disclosed herein is a low voltage signaling technique for integrated circuit systems that substantially reduces I/O power through the use of charge recycling stacked voltage domains.
FIG. 1 shows an input-output circuit having a charge-recycling stacked I/O scheme. FIG. 1 shows, more particularly, a two stack circuit 100 comprising domains 102 and 104 , with a mid supply node 106 between the two domains. Two groups of drivers are stacked between the supply voltage VDD and ground: M drivers 110 on the top domain 102 and M drivers 112 on the bottom domain 104 for a 2M-bit data bus. When the average current from the top drivers is equal to the average current from the bottom drivers, the mid-supply node VREG 106 is equal to 0.5 VDD, leading to a 0.5 VDD signal swing for both the top and bottom I/O domains 102 and 104 .
In the operation of circuit 100 , as the potential of the electrons decrease from VDD to VREG, that energy is used to perform logic in domain 102 . The electrons are re-used from VREG 106 to perform logic in domain 104 , thus resulting in a recycling of the current. Since the current from the top drivers 110 is reused by the bottom drivers 112 , the power efficiency of the drivers is significantly improved over the low-swing I/O with linear regulator or current-mode logic (CML) drivers. The receivers 114 and 116 recover the low-swing signals (0.5 VDD) to full-swing signals (VDD). Receivers 114 and 116 , it may be noted, may be in the voltage domain of VDD and ground. In an alternate embodiment, receiver 114 may be in voltage domain 102 and receiver 116 may be in voltage domain 104 .
In the stacked drivers, when the current from the top drivers 110 does not match the current from the bottom drivers 112 , the mid-supply node VREG deviates from 0.5 VDD, which reduces the voltage swing of either the top data bus or the bottom data bus. This deteriorates the overall I/O performance. Therefore, a voltage regulator 120 is added to stabilize the mid-supply node 106 . Since most of the time, the two currents match, the voltage regulator does not need to consume a lot of power or area. Thus, the overhead of the power and area of the voltage regulator is very low, and the overall power and area efficiency of the charge-recycling stacked I/O circuit 100 is very high.
FIG. 2 illustrates a calibration scheme 200 in accordance with an embodiment of the invention, for the charge-recycling stacked I/O scheme. With the circuit in FIG. 2 , a transmitter calibration block 202 and a receiver calibration block 204 have been added to the circuit 100 of FIG. 1 . The transmitter calibration block 202 and the receiver calibration block 204 sense the transmitter and receiver performance, respectively, and adjust the control codes 206 , 210 to the transmitter drivers 110 , 112 . A dedicated channel 212 connects the two calibration blocks 202 , 204 and sends control signals between them. The data rate of this channel can be very slow, so it does not require much power and area. On the transmitter side, the transmitter calibration block 202 gets the information from the mid-supply node VREG 106 and the receivers 114 and 116 and adjusts the control signals CTXTOP and CTXBOT. CTXTOP and CTXBOT control the driver strength of the drivers on the top and bottom domains 102 , 104 , respectively. On the receiver side, the receiver calibration block gets the information from the receiver data output and sends the information back to the transmitter calibration block 204 through the dedicated channel 212 .
Any suitable procedure may be used to measure or monitor the performances of the transmitters, the receivers, or the two domains 102 and 104 , or of the data transmitted through the input-output circuit. For example, as discussed in more detail below, calibration scheme 200 may be based on measuring or detecting errors, or the rate of errors, in the data sent from the transmitters in each of the voltage domains 102 and 104 .
FIG. 3 shows a calibration approach: open-loop calibration. This calibration approach, in embodiments of the invention, maintains the mid-supply node VREG at 0.5 VDD in different operating conditions. A voltage comparator 302 compares VREG 106 with a reference voltage 304 0.5 VDD that can be generated from a simple resistor divider or a complex band-gap voltage generator. The comparator output is sent to a control logic unit 306 (CLU). The CLU determines how to adjust the drivers 110 , 112 to pull VREG back to 0.5 VDD: if VREG <0.5 VDD, the top drivers 110 will be adjusted to be stronger; if VREG >0.5 VDD, the bottom drivers 112 will be adjusted to be stronger.
For example, as illustrated at 310 and 312 in a voltage-mode driver, each driver can have multiple transistors 314 , 316 . By turning on more transistors, the driver becomes stronger and the equivalent resistance is smaller; by turning off more transistors, the driver becomes weaker and the equivalent resistance is larger. In this way, VREG 106 can be adjusted toward 0.5 VDD. This calibration procedure, in embodiments of the invention, may be done with balanced data pattern to remove the effect of unbalanced data transition density. Therefore, a 0101 data pattern for example, may be chosen when this calibration is performed.
FIG. 4 shows another calibration scheme: load-aware driver calibration. This calibration approach, in embodiments of the invention, may be used to find an optimum operating balance for the transmitter between high performance and low power. As a general rule, for channels that are not very long and that do not have much channel loss, the greater the transmitter driver strength, the better the I/O performance. However, a larger transmitter driver strength normally means a higher transmitter power. Therefore, a tradeoff must be made between power and performance. In the calibration approach of FIG. 4 , a 0101 data pattern is sent through the transmitter to the channel. The transmitter is initially set to maximum driver strength, which means the signal swing is at its maximum value. On the receiver side, a data monitor 402 measures the receiver output. The receiver CLU 404 adjusts the input receiver threshold voltage. The receiver threshold voltage is slowly adjusted until the data monitor detects a data error (that is, a pattern that is not the 0101 pattern).
In this way, the CLU 404 detects the receiver vertical data eye. Also, based on the system specifications and operating conditions, a preset receiver vertical data eye threshold voltage is determined. When the receiver vertical data eye is larger than the preset eye threshold voltage, the I/O can function with acceptable performance over various operating conditions. The receiver CLU 404 compares the detected receiver vertical data eye and the preset eye threshold. If the detected receiver vertical data eye is larger than the preset eye threshold, the receiver CLU 404 sends a request signal to the transmitter to reduce the driver strength. If the detected receiver vertical data eye is smaller than the preset eye threshold voltage, the receiver CLU 404 sends a request signal to the transmitter to increase the driver strength. This procedure is repeated until the detected receiver data eye is reduced to the preset receiver eye threshold.
Similarly, the calibration scheme presented in FIG. 4 can also be performed with a horizontal data eye. The horizontal data eye can be measured by adjusting the receiver clock phase. The measured horizontal eye is compared with a preset horizontal eye threshold. The transmitter drivers are adjusted until the measured horizontal eye is near the preset horizontal eye threshold.
In FIG. 4 , all the drivers in the top and bottom driver groups are adjusted together to increase or decrease the driver strength. The calibration schemes in FIG. 3 and FIG. 4 are independent of each other; and in embodiments of the invention, a circuit may be provided with both calibration approaches, and the two approaches can be separately performed.
Due to process variations in the manufacture of the integrated circuit, the performance of the top drivers 110 and bottom drivers 112 may be different and the performance of the top receivers 114 and the bottom receivers 116 may also be different. Therefore, the optimum mid-supply voltage VREG 106 , may not necessarily be 0.5 VDD. The calibration scheme in FIG. 5 handles this issue and tries to set VREG at an optimum voltage level, Vopt. This calibration scheme operates in a way similar as that of the calibration scheme in FIG. 4 . VREG is adjusted based on the performance of the top and bottom receivers 114 and 116 . A receiver data monitor 502 is provided to monitor the performance of the top receivers 114 and the bottom receivers 116 , and if the top receivers have better performance than the bottom receivers, i.e., larger input receiver data eye, VREG will be increased. If the bottom receivers 116 have better performance than the top receivers 114 , VREG will be decreased. This is repeated until the top and bottom receivers have the same performance.
Different from the calibration schemes shown in FIG. 3 and FIG. 4 , the calibration scheme shown in FIG. 5 does not make VREG equal to 0.5 VDD (the voltage comparator shown in FIG. 3 and FIG. 4 is not shown in FIG. 5 ). From the feedback from the receiver CLU 504 , the transmitter CLU 506 directly changes the transmitter driver strength in one of the two driver groups 110 , 112 until the top and bottom receivers 114 and 116 have, for example, the same receiver vertical data eye. Other parameters may be used to measure the performance of the top and bottom receivers.
The description of the present invention has been presented for purposes of illustration and description, and is not intended to be exhaustive or to limit the invention in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope of the invention. The embodiments were chosen and described in order to explain the principles and application of the invention, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use contemplated. | A method and system are disclosed for calibrating a mid-voltage node in an integrated circuit including an input-output circuit having charge-recycling stacked voltage domains including at least first and second voltage domains. In one embodiment, the method comprises transmitting data through the input-output circuit, including transmitting a first portion of the data across the first voltage domain, and transmitting a second portion of the data across the second voltage domain. The method further comprises measuring a specified characteristic of the data transmitted through the input-output circuit; and based on the measured specified characteristic, adjusting a voltage of said mid-voltage node to a defined value. The voltage of the mid-voltage node may be adjusted to accomplish a number of objectives, for example, to achieve a desired trade-off between power and performance, or so that the two voltage domains have the same performance. | 7 |
FIELD OF THE INVENTION
[0001] The invention relates to the field of the identification of individual beverage containers.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to the differentiating of beverage containers in order to differentiate users' drinks. Many social situations involve the serving of beverages in glasses, cups, bottles, cans, boxes or pouches. Typically the glasses, bottles, cans, boxes or pouches in a set will be of the same pattern, making it difficult for different users to determine which drink is theirs once the containers are set down.
[0003] This can lead to negative consequences, for instance, the spread of disease when someone drinks from the container that a sick person has been using. Another negative consequence can be an allergic reaction in a person who unwittingly consumes a drink containing a substance to which they're allergic. In a setting where people are gathered and alcohol is served, some patrons may argue or physically fight over a perceived theft of their drink. In an event with children involved, not only are there typically many germs to be spread, but children may get very angry and act inappropriately if another child takes their drink. Additionally, many people are just queasy about sharing germs with anyone. There are attempts to remedy this situation in the prior art, which are listed below.
[0004] U.S. Pat. No. 5,927,524 teaches a safety blanket for a baby bottle formed from two very thin flat layers of a liquid impervious material. The two layers of material are sealed around the periphery with the central body portion not attached so as to form a dead air space there between. The two layers are in the general shape of a rectangle with the shorter surface sufficiently sized to reach from top bottom of the bottle height, and the longer dimension sufficient to surround the circumference of the bottle reservoir. A fastening method for attaching the safety blanket around the bottle is provided as is an envelope associated with the fastening method for inserting a substrate with indica thereon.
[0005] U.S. Pat. No. 6,412,632 and U.S. Pat. No. 6,508,361 teach a personal identification method and system for improving personal hygiene in which provision is made for identifying a beverage, food product, or the like, with a particular person so that another person does not inadvertently access the identified item unintentionally. Identifying indicia such as numbers or alphabetical letters are selectable and conditioned by the user to be prominently displayed on the item so as to identify it with the individual involved. For necked beverage containers, in one embodiment, a re-usable snap-on display device, or assembly, is configured to snap onto the neck of the container; in another embodiment, the existing conventional cap-attaching ring is modified to include alpha-numeric indicia and/or to receive a cooperating indicia-indicating display element. For beverage cans, a wand-like element portraying selectable alpha-numeric indicia is attached to the conventional snap ring opener; and for boxed beverages, a plurality of selectable identifying apertures are provided so that the user can personally distinguish his or her beverage from those of others.
[0006] U.S. Pat. No. 7,243,795 teaches an identification system that distinguishes among a set of individual containers. The identification system has an identifier member associated with each of the containers in the set for facilitating visual discrimination of each of the containers from the others of the set. The identifier member of each container in the set has distinct and visibly different printed identifying indicia positioned over a surface portion of the container, and an opaque covering material covering the printed identifying indicia. The opaque covering material is removable to selectively expose a preselected one of the printed identifying indicia so that during consumption of the contents of the container a user may readily distinguish his container from the other containers in the set by visual inspection of the exposed printed identifying indicia.
[0007] U.S. Patent App. No. 2007/0068944 teaches a method of personalizing a beverage bottle which comprises providing a bottle assembly with a side wall having an exterior surface. An array of selectable sleeve wraps are provided, each configured to fit on the side wall of the bottle assembly. Each sleeve wrap has at least one characteristic that is visibly different from the other sleeve wraps of the array. One of the sleeve wraps is selected from the array and attached on the side wall of the bottle assembly.
[0008] U.S. Patent App. No. 2005/0223642 teaches a sleeve comprising a lower portion preferably having a base portion and a skirt portion for packaging a floral grouping or plant. The sleeve may have an upper portion which can be detached from the lower portion of the sleeve once the function of the upper portion has been completed. The sleeve has a plurality of horizontally and diagonally positioned expansion elements.
[0009] U.S. Patent App. No. 2006/0186129 teaches a storable, reusable-insulating sleeve for a beverage container that provides insulation to the user from hot or cold beverages. The improved sleeve maintains insulation of hot temperatures approximately five and ten degrees higher for a thirty-minute interval, than, for example, cardboard counterpart sleeves. The improved sleeve comprises an integral storage-securing mechanism for storing the sleeve in a compact form. The compact form can easily fit into a pocket, purse, car glove compartment or desk drawer. The sleeve is made of various fabrics and is therefore reusable. Further, a pocket contained in the sleeve will accommodate a prepaid card or a key, for storage, transport and gift giving.
[0010] U.S. Patent App. No. 2006/0207132 teaches a system for identifying a specific beverage container among a group of beverage containers. The system can include an elastic band sized for elastically engaging an outer surface of an individual beverage container, and a tag secured to the elastic band. The tag can be removably secured to the elastic band by a clip. The tag can include at least one surface for displaying identifying indicia thereon in such a way as to permit the identifying indicia to be repeatedly changed or altered by a user.
[0011] U.S. Patent App. No. 2004/0195254 teaches a flexible composite band to identify an individual drinking container with at least two layers of material and method of manufacture and use are disclosed. The first layer is a flexible layer generally constructed from elastic. The second layer is a decorative layer that can be customized to suit one's tastes and is attached directly to the elastic layer. Once this composite flexible identification band is formed it can be placed around drinking containers of various sizes and shapes and allow for easy identification of a drinking container due to the unique decorative layer.
[0012] Co pending U.S. Ser. No. ______ by the current inventors teaches a method of identifying a beverage utilizing either differentiated stirrers or a unique band, however, this application does not teach the article of the present invention.
[0013] The present invention has advantages that the prior art lacks. The prior art cites inventions which are more difficult to make and subsequently increase the cost to the consumer. Many of the prior art inventions are specific to a type of container and cannot be used on a variety of different containers. Many of the prior art inventions are meant to be re-usable, whereas the present invention is meant to be disposable, although it can be re-used if desired. The prior art also does not address printing on the band as used for a beverage container identifying device. In the case of patent application 2004/0195254, for instance, the band is manufactured with a design and is not differentiated by printing or writing. U.S. Patent App. No. 2006/0207132 addresses a plastic tag which can be written on with a specific type of pen and then attached to a band on a beverage container, the tag being re-usable. It does not address a printed or band with writing on it. In addition, some inventions cited have uses other than drink differentiation.
[0014] One possible solution outside of the present invention and prior art would be to write on the outside of the beverage containers, but this is not generally feasible. In the case of a cocktail party a hostess would not want her glasses defaced, nor would the bar or club owner in their establishment. In the case of disposable containers, many beverage cans and pouches are made from metal or foil, which is difficult to write on. Plastic bottles may weep and erase writing or be difficult to write on initially, and their labels are difficult to write on either because of the material from which they are made or because they are so covered in color and writing that it is difficult to find a place where the writing will show. Glass bottles are difficult to write on as well, and individual beverage boxes are coated with a wax. Finding a writing utensil that may work on any of these surfaces is not always possible, and may not be desirable if young children can access it and write on other surfaces, such as sofas or walls. Writing utensils also are easily misplaced at a party and may be difficult to find, especially in a social situation.
[0015] The present invention is quick, easy to use, and relatively inexpensive. It can also add to the festivity of a party in a number of ways, a few of which are listed here. Upon arriving at an event where the device is available, attendees could pick a pattern of their choice, or patterns could be tailored to their professions or other attributes and presented to them at the party. The device could also be identified with a photo that has some meaning to an attendee. The invention could be personalized, so that each person at an event would feel welcomed by finding devices with their name or other meaningful identifier. The invention could contain a joke, so strangers at a gathering could use it as an icebreaker when wishing to speak to someone. A company desiring to host an event and promote its services could use the invention to advertise in a subtle manner. The invention could be used in a game, such that the person with the device containing a certain pattern wins a prize.
[0016] The present invention has uses in many different types of social situations. One venue in which the invention is particularly useful is at cookouts, cocktail or other parties, where people are drinking alcoholic beverages (many times out of glasses or bottles) and may need a reminder which drink is theirs, especially if they set it down next to other drinks. Another situation that would benefit from the invention is a crowded bar or club, where people may put their bottles or glasses down in order to dance or mingle, and would not want to pick up the wrong bottle or glass.
[0017] Another venue that would profit from the current invention would be any gathering of children, particularly a play group or birthday party. Children forget about their drinks in the excitement of play, then want them again when they get thirsty. The invention would help hosts or care givers determine which drink belongs to which child. Caregivers at a daycare could easily identify a child's bottle, sippy cup or beverage by the band including having the child's name or identifying insignia on the band. School children could easily identify their own bottle of water or beverage by using the band.
[0018] Other venues include sporting events and practices, where the athletes are repeatedly setting down and retrieving their drinks. This is particularly true for younger players in community or school leagues who have to supply their own drinks and often do so in disposable beverage containers. People exercising at a gym could easily identify their own bottle of water or beverage by having placed their preferred band on their beverage. Children participating in sports or recreation such as baseball, karate or ballet could easily identify their own beverage.
[0019] A family who buys beverages and has members who don't finish an entire drink could benefit as well, by using the device to label the beverage to save for later use. This would save money and shopping trips. The family could also use the device when going on trips, to keep drinks from being confused in the car or on the train or plane, and to try to avoid arguments during the trip.
[0020] Preferred embodiments of this invention are illustrated in the accompanying drawings and will be described in more detail herein below.
SUMMARY OF THE INVENTION
[0021] The invention is an article of manufacture comprising a unique identifying device capable of identifying a user's beverage container, in particular, a band having at least one first portion and at least one second portion, the first portion or portions having first and second ends, and the second portion or portions also having first and second ends, wherein the first end of each first portion is connected to the first end of a second portion, and the second end of each second portion is connected to a second end of a second portion.
[0022] The invention solves the problem of users' being unable to distinguish their beverage from other users' beverages in a situation where more than one person is or has been present, or where opened beverages are stored for later use. The invention consists of unique bands for use on the outside of glasses, cups, cans, bottles, boxes, cartons or other beverage containers. The uniqueness of the bands is obtained either by manufacturing them with different patterns or writing, including one of each unique pattern or writing per set of devices sold to the consumer, or making them in a set of varying colors, including one of each unique color per set of devices. The band can also be rendered unique by writing on it by hand. The preferred band composition is a stretchable material alternating with another material to form a band, the other material preferably being a material which will accept printing or writing, and most preferably the material is ribbon.
[0023] It is an object of the invention to differentiate otherwise identical or similar beverage containers.
[0024] It is an object of the invention to promote better health by aiding the prevention of the spreading of germs and diseases through inadvertently shared beverages.
[0025] It is an object of the invention to provide an easy, quick, and inexpensive method of differentiating beverage containers.
[0026] It is an object of the invention to add a festive atmosphere to a social situation by providing designs for beverage containers.
[0027] It is an object of the invention to be able to personalize and/or accessorize beverage containers.
[0028] It is an object of the invention to promote sponsorship and advertising by allowing the placement of a logo, advertisement, photo or other promotional item on a band on the outside of a beverage container or on a stirrer to be used in a beverage container.
[0029] It is an object of the invention to allow later identification after storage of partially consumed beverages in their original containers.
[0030] It is an object of the invention to help a parent or caregiver differentiate their child's juice or beverage box, pouch, bottle or sippy cup from those of other children in any setting where children are grouped together, such as a party, play group or daycare.
[0031] It is an object of the invention to avoid quarrels over ownership of a beverage, particularly in situations with children, or with adults who have been consuming alcohol.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] FIG. 1 is a perspective view of a preferred embodiment of the invention, showing a band that is composed of a portion of stretchable material and a portion of printable material.
[0033] FIG. 2 is a perspective view of a preferred embodiment of the invention, showing a unique band with a stretchable material portion and a printable material portion on a beverage bottle.
[0034] FIG. 3 is a perspective view of a preferred embodiment of the invention, showing a set of unique bands, each with its own design on the printable portions and each with two stretchable portions alternating with two printable portions.
[0035] FIG. 4 is a perspective view of a preferred embodiment of the invention showing a band with two stretchable portions alternating with two printable portions.
[0036] FIG. 5 is a perspective view of a preferred embodiment of the invention showing a band with three stretchable portions alternating with three printable portions.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0037] The preferred embodiments of the present invention will now be described with reference to FIGS. 1-5 of the drawings. Identical elements in the various figures are identified with the same reference numerals.
[0038] The invention includes identifiers for both re-usable containers such as glasses and cups, and disposable containers such as bottles, cans, cartons, boxes and pouches. Containers are differentiated with an identifying component that is added to the container at the time of use and, in the case of disposable containers, may be disposed of with the container. The identifying component can be retained or disposed of when used with re-usable containers, depending on the user's desire. More specifically, multiple uniquely designed bands are used for differentiating between multiple disposable containers.
[0039] The embodiments shown in FIGS. 1-5 employ a device which is an addition to a beverage container and that allows for differentiation of containers which otherwise would be identical to each other. FIG. 2 demonstrates how the invention can be applied to beverage containers such as bottles. The invention can similarly be applied to cans, boxes or pouches.
[0040] The stretchable portions of the band, or the first portions, allow for the band to be stretched for placement on a beverage container, and the second portion or portions are made from other material, preferably material that accepts writing or printing.
[0041] A preferred embodiment of this configuration is seen in FIG. 1 . The band is composed of alternating portions of stretchable materials and another material. The other material comprising the second portion can be any suitable material, including but not limited to elastic, paper, plastic, spandex, rubber, vinyl, cellophane, cloth, animal skin, cardstock, cardboard, wood, metal, wax, foil, or food. One highly preferred material is ribbon, since it is inexpensive and can be printed or written onto easily.
[0042] Thus, the configuration of the embodiment described generally in FIG. 1 can comprise multiple configurations. For example, the band could have one portion of stretchable material attached to a single portion of the other material. Or, as seen in FIGS. 3 , 4 and 5 , the band could comprise 2 or more separate portions of stretchable material and 2 or more portions of the other material. Moreover, if a band is made with more than one stretchable portion, the stretchable portions can be the same or different stretchable material, and portions made from other material can be the same or different materials. For example, a ribbon connected to elastic which is connected to cardboard, or ribbon connected to cardboard connected to elastic connected to other material, and so on.
[0043] The dimensions of the embodiment seen in FIG. 1 can be any size or width as appropriate, with preferred dimensions for the ribbon/other material being two 3½″ by 1″ pieces connected by two 1½″ by 1″ pieces of elastic/stretchable material. Both the ribbon/material and the elastic/stretchable material can have variable lengths and widths. Thus, for example, the first portion or portions can be flush with the second portion or portions, or they can independently be of differing widths. The same is true with the lengths, with each portion having the same or independently different lengths.
[0044] The first and second portion or portions can be attached together using any suitable method, including but not limited to, gluing, sewing or stapling, or one or more fasteners using mechanical fasteners, such as snaps, rivets, buttons, etc.
[0045] The band may be any width or length, with a preferred width of 1 inch and a preferred length of 7 inches, and may wrap around the bottle any number of times or any fraction of one time. It is preferred to be constructed to slip over the bottle as one continuous loop or to be wrapped around and fastened to itself or to the bottle by an adhesive or other closure method. It may also be of any geometrical shape, including a rectangular strip as shown, rectangular with the top or bottom or both edges serrated, or any geometric shape including but not limited to a triangle, star, square, polygon, circle or combination thereof, including multiple repeats of shapes. The band may be disposable or re-useable.
[0046] The placement of designs, wherein the term “designs” means patterns, photos, personalizations, logos, jokes, or any writing, on the band may employ, but is not limited to, the following methods: having designs printed on the band, having bands made with the designs as an integral part of the manufacture process, hand-drawing designs on the band, having the designs cut out of the band by die-cutting or other cutting methods, or having design stickers placed on the band. The designs may be placed on any fraction of the band or on the entire band. In a preferred embodiment, the designs may be placed on the outside of the band. Also, designs may be placed on the inside of the band, either alternatively or in conjunction with designs on the outside of the band. For instance, in the case of a joke or trivia question, the question may be printed on the outside of the band and the answer on the inside of the band.
[0047] The preferred band materials are one stretchable material, such as the elastane, material and one material that can be printed on rigid material, such as ribbon, but it may be made of any suitable material, including but not limited to elastic, paper, plastic, spandex, elastane, rubber, vinyl, cellophane, cloth, animal skin, cardstock, cardboard, wood, metal, wax, foil, or food. The band may be one continuous material or may be made of one or more portions of a stretchable material, such as an elastane, alternating with the aforementioned materials.
[0048] The bands may be differentiated from each other by using different patterns, logos, photos, jokes, personalizations or writings in a set of bands, or by using different colors for otherwise identical bands in a set. Especially preferred are designs promoting or advertising products or companies.
[0049] FIG. 1 illustrates a unique identifying device that is a band 100 with an optional pattern 112 . The band has a top edge 130 , a bottom edge 140 , an outside surface 150 , an inside surface 160 , a stretchable material section 165 , a second portion that may or may not be stretchable but is capable of receiving writing 170 , band end one 180 , and band end two 190 . FIG. 1 also illustrates a stretchable portion first end 163 , a stretchable portion second end 167 , a second portion first end 168 , and a second portion second end 172 .
[0050] FIG. 2 illustrates another embodiment of the invention, the unique identifying device that is a band 100 on a beverage bottle 105 . FIG. 2 shows a band that has a logo 120 which can be customized to allow differentiation of multiple bottles or used to advertise or promote a product or service. The band has a top edge 130 , a bottom edge 140 , and an outside surface 150 . The band has a stretchable material portion 165 and a second portion 170 engineered to receive writing, printing or an adhesive, including but not limited to a pattern, logo, photo, joke, or any kind of personalization or adhesive sticker. FIG. 2 also illustrates a stretchable portion first end 163 , a stretchable portion second end 167 , a second portion first end 168 , and a second portion second end 172 . The portion 170 can encompass the entire band or any part or parts of the band. A set of bands may contain the same writing or printing but be differentiated by band color.
[0051] FIG. 3 illustrates a unique identifying device that is a set of bands 120 , each with a different pattern. One band has a line pattern 112 , one has a geometric shapes pattern 114 , and one has a heart pattern 116 . The bands have a top edge 130 , a bottom edge 140 , an outside surface 150 , an inside surface 160 , two stretchable material portions 165 , two second portions capable of receiving writing, printing, or an adhesive, such as a pattern, logo, photo, joke, personalization or adhesive sticker 170 , band end one 180 , and band end two 190 . FIG. 3 also illustrates two stretchable portion first ends 163 , two stretchable portion second ends 167 , two second portion first ends 168 , and two second portion second ends 172 . The band ends may be overlapped any number of times and adhered to each other, or the band ends may be adhered to the container directly. The entire band may also be adhered to the beverage container directly.
[0052] FIG. 4 illustrates a unique identifying device that is a band 100 , with an optional pattern 112 . The band has a top edge 130 , a bottom edge 140 , an outside surface 150 , an inside surface 160 , two stretchable material portions 165 , two second portions capable of receiving writing, printing, or an adhesive, such as a pattern, logo, photo, joke, personalization or adhesive sticker 170 , band end one 180 , and band end two 190 . FIG. 4 also illustrates two stretchable portion first ends 163 , two stretchable portion second ends 167 , two second portion first ends 168 , and two second portion second ends 172 . The band ends may be overlapped any number of times and adhered to each other, or the band ends may be adhered to the container directly. The entire band may also be adhered to the beverage container directly.
[0053] FIG. 5 illustrates a unique identifying device that is a band 100 , with an optional pattern 112 . The band has a top edge 130 , a bottom edge 140 , an outside surface 150 , an inside surface 160 , three stretchable material portions 165 , three second portions capable of receiving writing, printing, or an adhesive, such as a pattern, logo, photo, joke, personalization or adhesive sticker 170 , band end one 180 , and band end two 190 . FIG. 4 also illustrates three stretchable portion first ends 163 , three stretchable portion second ends 167 , three second portion first ends 168 , and three second portion second ends 172 . The band ends may be overlapped any number of times and adhered to each other, or the band ends may be adhered to the container directly. The entire band may also be adhered to the beverage container directly.
[0054] Although this invention has been described with a certain degree of particularity, it is to be understood that the present disclosure has been made only by way of illustration and that numerous changes in the details of construction and arrangement of parts may be resorted to without departing from the spirit and the scope of the invention. | The invention provides a unique identifying device that differentiates identical or similar beverage containers. In the case of cans, bottles, boxes, or pouches, a highly preferred band composition is elastic alternated with other material, preferably ribbon that will accept printing or writing. The invention is further a set of such bands, each with its own design, placed around the outside of individual containers to enable users to distinguish their beverage from others that are in the same type of container.
The invention has the advantage of being quick and easy to use, and is inexpensive enough to be disposable. It is an object of the invention to identify individual beverage containers using a unique identifying device. | 6 |
BACKGROUND OF INVENTION
The present invention relates generally to ultrasonic metal welding and, more specifically, to an ultrasonic welding apparatus that reduces sonotrode adhesion during the ultrasonic welding process.
Ultrasonic welding of various materials is known. The process involves vibrating overlapping or adjacent workpieces clamped between a sonotrode and an anvil. Frictional forces occurring between the vibrating workpieces create a bond or weld that occurs at the interface between the workpieces, effectively joining them to one another. Accordingly, various sonotrode and anvil surface configurations, i.e., the surface that contacts the workpieces, are known and used to transfer energy from the sonotrode to the aforementioned interface. Such configurations attempt to reduce the energy loss at the sonotrode/workpiece interface or the anvil/workpiece interface thereby increasing the energy to the workpiece/workpiece interface and increasing the overall efficiency of the ultrasonic welding apparatus.
Further, it is known that when using an ultrasonic welding apparatus to weld light metals, specifically aluminum, the sonotrode or more specifically, the sonotrode adheres to the workpiece being welded. The adhesion can be so severe as to (i) damage the weld when detaching the sonotrode from the joined workpieces, (ii) cause significant and unacceptable distortion of the work piece surface, and (iii) render the sonotrode unusable for subsequent welds. Sticking or adhesion to the workpiece generally results from the sonotrode sliding on the workpiece. When the sonotrode slides, it causes galling or a buildup of material on the sonotrode.
With many of the current sonotrode designs and surface configurations, each time the sonotrode performs a weld, a small amount of aluminum is transferred unto the sonotrode. Continued welding operations cause the aluminum to build up on the sonotrode surface. The built up aluminum on the sonotrode bonds with the material of the workpiece. When this occurs, the sonotrode sticks to, or in short, becomes welded or bonded to the workpiece. Forces of up to 5kN may be required to detach the bonded sonotrode from the workpiece material. Additionally, as aluminum builds up on the sonotrode, it clogs the gripping surface of the sonotrode and reduces the efficiency of the ultrasonic welding apparatus because the energy transferred to the workpiece to perform the weld is reduced.
When the sonotrode becomes clogged, the useful life thereof is reduced. The practical consequence of this is that the sonotrode needs to be cleaned after each weld. Moreover, the surface of the welded material may be severely damaged and will require costly craftsmanship work before it will meet surface finish specifications.
Therefore, there is a need in the art to provide an ultrasonic welding apparatus designed such that it reduces aluminum/sonotrode adhesion during the ultrasonic welding process while improving the productivity, manufacturing speed and reducing equipment downtime by reducing the sticking phenomenon that is common when ultrasonically welding materials.
SUMMARY OF INVENTION
Accordingly, the present invention is an ultrasonic welding apparatus and method that reduces adhesion between the welding sonotrode and the workpiece during the welding process.
In one embodiment, a fluid is deposited on a contact surface of the sonotrode before the welding process. The fluid may be deposited in several ways all of which are within the scope of the invention. For instance, in one embodiment, the fluid travels through a passageway in the sonotrode to an aperture located on the contact surface of the sonotrode. The fluid is held within the passageway by capillary action. The contact surface may also include at least one groove thereon to aid in distributing the fluid on the contact surface.
In accordance with an additional embodiment, a cooling medium engages the sonotrode and cools the sonotrode below the dew point of the surrounding atmosphere, causing moisture to condense or form on the contact surface of the sonotrode. The cooling medium may be externally blown across the sonotrode or it may travel through various passageways located within the sonotrode.
A further embodiment utilizes the use of cooling fins connected to the sonotrode to cool the sonotrode to a lower temperature, one at which the sonotrode is less likely to stick to the workpiece.
Further, the present invention provides a method for reducing sonotrode adhesion. The method includes several steps operating alone or in combination, including the step of depositing a liquid on the contact surface of the sonotrode. This can be accomplished by using a passageway through the sonotrode to transfer liquid to the contact surface. In addition, the sonotrode and corresponding contact surface can be cooled via a cooling medium, to below the dew point of the surrounding atmosphere thereby causing moisture to condense on the sonotrode.
In addition, cooling the sonotrode before performing the welding process further prevents sonotrode adhesion. Various steps can be taken in to cool the sonotrode including the use of internal cooling passageways in the sonotrode.
Other features and advantages of the present invention will be readily appreciated, as the same becomes better understood after reading the subsequent description taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a schematic view of an ultrasonic welding apparatus utilizing a sonotrode in accordance with the present invention.
FIG. 2 is a side view of a sonotrode according to the present invention for use with an ultrasonic welding apparatus.
FIG. 3 is a bottom view of the sonotrode of FIG. 2 according to the present invention.
FIG. 4 is a side view of an alternative embodiment of a sonotrode according to the present invention for use with an ultrasonic welding apparatus.
FIG. 5 is a bottom view of the sonotrode of FIG. 4 according to the present invention.
FIG. 6 is a side view of a further alternative embodiment of a sonotrode according to the present invention for use with an ultrasonic welding apparatus.
FIG. 7 is a bottom view of the sonotrode of FIG. 5 according to the present invention.
FIG. 8 is a bottom view of a further alternative embodiment of a sonotrode according to the present invention for use with an ultrasonic welding apparatus.
FIG. 9 is a side view of the sonotrode of FIG. 8 according to the present invention.
DETAILED DESCRIPTION
FIG. 1 shows a wedge-reed ultrasonic welding apparatus, seen generally at 10 , according to the present invention. The ultrasonic welding apparatus 10 includes a reed 12 , connected to sonotrode 14 , mounted for movement in a side-to-side or horizontal direction of vibration, shown by the arrow 16 . The reed 12 also moves in a vertical manner, shown by the arrow 18 , and in cooperation with an anvil 20 clamps the first 22 and second 24 workpieces in position. Once the workpieces 22 , 24 are clamped, a transducer 15 , connected to the reed via the wedge 11 , vibrates the sonotrode 14 at a high frequency (typically 15 to 40 kHz) to impart energy to the first 22 and second 24 workpieces at a location between the sonotrode 14 and the anvil 20 to create a bond or weld at the interface or adjacent surfaces 26 of the workpieces 22 , 24 in accordance with known ultrasonic welding processes. As used herein the term sonotrode generally refers to the tool attached to the reed 12 . In many cases, the sonotrode also includes a replaceable sonotrode tip. Accordingly, the sonotrode is the gripping tool attached to the end of the reed 12 .
As shown in FIG. 2, a sonotrode 14 is inserted into the body 29 of the reed 12 . Applying a liquid, such as water, in a small amount to the contact area located between the contact surface 28 of the sonotrode 14 and the workpiece 22 prior to welding the overlapping workpieces 22 and 24 helps to prevent the sonotrode 14 from sticking to the workpiece 22 . One method for depositing a fluid on the contact surface 28 of the sonotrode 14 is by feeding a liquid through an aperture 34 at that contact surface 28 of the sonotrodel 4 . One way of feeding the liquid is to provide the sonotrode 14 with an inner cavity 30 . The inner cavity 30 forms a reservoir that stores a liquid. The liquid passes from the inner cavity 30 or reservoir through a capillary feed tube or passageway 32 to the contact surface 28 of the sonotrode 14 . As known in the art, the contact surface 28 is the surface that contacts the workpiece 22 to impart energy to the workpieces 22 , 24 to perform the weld. The capillary feed tube 32 terminates at an aperture 34 in the contact surface 28 of the sonotrode 14 .
A supply hose 36 extends through the body 29 of the reed 12 and into the inner cavity 30 . An O-ring 38 seals the supply hose 36 within the inner cavity 30 . Accordingly, as fluid exits the inner cavity or reservoir 30 through the capillary feed tube 32 , the supply is replenished via the supply hose 36 . As shown in FIG. 2, the liquid is supplied by gravity and capillary action. The capillary feed tube 32 is small enough to allow capillary forces to stop free-flowing of the liquid when the sonotrode 14 is not in contact with the workpiece 22 . In the preferred embodiment, the holes are large enough and preferably have an angular opening 34 that will not easily the clogged by small particles picked up or located on the workpiece 22 . The preferred embodiment utilizes a capillary feed tube having a diameter of about 1-1.5 mm; at about 2 mm the capillary forces are no longer active to the same extent. It should be understood that the capillary forces and correspondingly diameter of the capillary feed tube 32 will vary depending upon the type of liquid used.
In addition, the liquid may also be supplied by a low-pressure micro pump located either in the reed 12 or separate from it, wherein the supply hose 36 extends down through the reed 12 . Further, the sonotrode 14 may include a plurality of apertures 34 in the contact surface 28 to aid in distribution of the liquid. If necessary, to further aid in distribution of the liquid to the entire contact surface 28 , one or more grooves 40 can be formed in the sonotrode 14 . In many instances, the contact surface 28 may have a knurled pattern thereon to aid in gripping the workpiece. Preferably, the grooves 40 are made slightly deeper then the knurled or gripping pattern formed on the sonotrode 14 to allow the grooves 40 to remain open during the initial stages of the ultrasonic welding process. It should be understood that the contact pressure between the contact surface 28 and the workpiece 22 stops the liquid from flowing once the welding process has started.
The means for depositing a fluid may also include an apparatus that applies a cooling medium, such as nitrogen or carbon dioxide, to the sonotrode 14 . The medium would cool the contact surface 28 of the sonotrode 14 to a temperature below the dew point of the surrounding atmosphere, whereby water vapor would condense on the surface of the sonotrode 14 . The moisture would affect no other part of the ultrasonic welding apparatus. The damp or wet surface would then have the non-stick properties set forth previously.
Other means for depositing moisture or fluid on the contact surface are also contemplated, including using a spray head to apply moisture to either the contact surface of the sonotrode 14 or the workpiece 22 . Moisture may also be applied by dripping, brushing or pressing a wet sponge on the sonotrode 14 or workpiece 22 .
Shown in FIGS. 4-8 are further embodiments of a sonotrode 14 according to the present invention including structure for cooling the sonotrode 14 . FIGS. 4-5 show a sonotrode 14 having radially extending fins 50 for external airflow cooling of the sonotrode 14 . The fins 50 are formed out of material that readily conducts heat away from the sonotrode 14 . In addition, a separate or nearby supply of air, or some other suitable medium, may be forced through or by the fins 50 to further increase the cooling effect thereof. As shown in the additional embodiments, air or some other cooling medium may pass internally through the sonotrode 14 and exit in an area adjacent the fins 50 to further cool the sonotrode 14 .
Turning now to FIGS. 6-7, there is shown a further embodiment of the present invention utilizing internal cooling passages. As shown in FIGS. 6-7, a passage 60 extends longitudinally through the center of the sonotrode 14 . The passage 60 connects with a plurality of radially extending exhaust passageways 62 ending at exhaust ports 64 . Preferably, the cooling fluid is an air or some other gas that is supplied via a supply hose to the passageway 60 . The supply of cooling fluid may be continuous or may be supplied in short bursts that coincide with or are immediately after the welding cycle is complete. As set forth above, such cooling passages may be combined with the cooling fins 50 of the previous embodiment wherein the cooling medium flows passed the fans 50 .
FIGS. 8-9, show a further embodiment of a sonotrode 14 having an internal cooling circuit 70 . The internal cooling circuit 70 includes an inflow passage 72 and an outflow passage 74 connected by a transverse passage 76 . As shown, the transverse passage extends inwardly from a side surface 78 of the sonotrode 14 . This is for ease of manufacturing, as it provides a simple way to connect the inflow 72 and outflow 74 passages. A plug 80 seals the opening at the side surface 78 . In use, the cooling medium, typically a liquid cooling fluid, flows in the inflow passage 72 in the direction shown by arrow 82 , across the transverse passage 76 and out the outflow passage 74 in the direction shown by arrow 84 . In this manner, fluid flowing through the sonotrode 14 acts to cool the sonotrode 14 . Depending upon the cooling medium used, such and internal cooling circuit 70 may be used to cool a sonotrode 14 to a temperature below the dew point. While shown here with a single inflow 72 and outflow 74 passages, multiple passages may be used to further increase the flow of coolant through the sonotrode 14 . The internal cooling circuit 70 may also be used in combination with the cooling fins 50 of the previous embodiment.
In addition, the various cooling embodiments may be combined with the fluid application embodiment such that the combination thereof further reduces the likelihood that the sonotrode 14 will stick to the workpiece 24 . For instance, it is contemplated that the internal and extra cooling embodiments of FIGS. 4-9 may be used in connection with the means for depositing a fluid disclosed herein. While we do not seek to be held for rigorous scientific exactitude, we postulate that the dropletization and/or evaporation of the liquid (both of which are visible during the practice of this invention), trapped between sonotrode 14 and material 22 , produce enough pressure surge to cause their separation, thus preventing sticking.
Although the wedge-reed configuration is used to describe the various embodiments of this invention, it is to be understood that the terminology that has been used is intended to be in the nature of words of description rather than of limitation.
Many modifications and variations of the present invention are possible in light of the above teachings. Therefore, within the scope of the appended claims, the present invention may be practiced other than as specifically described. | An apparatus and method for ultrasonically welding workpieces that reduces sonotrode adhesion during the ultrasonic welding process. The sonotrode includes a contact surface wherein a fluid is deposited on the contact surface prior to the welding process. The fluid may be applied in different ways, including providing an aperture in the contact surface of the sonotrode. In addition, the sonotrode may be cooled below the dew point of the surrounding atmosphere thus causing moisture to form on the contact surface of the sonotrode. Cooling the sonotrode to a temperature above the dew point also reduces sonotrode adhesion during the ultrasonic welding process. | 1 |
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS
This application is a U.S. National Phase application under 35 U.S.C. §371 of International Patent Application No. PCT/CN2012/075418, filed May 13, 2012, and claims the benefit of Chinese Patent Applications No. 201110129366.5, filed on May 18, 2011 and No. 201110304298.1, filed Oct. 2, 2011, all of which are incorporated by reference in their entirety herein. The International Application was published on Nov. 22, 2012 as International Publication No. WO/2012/155816 under PCT Article 21(2).
FIELD OF THE INVENTION
The present invention relates to a dustproof and waterproof multipurpose LED-light power source assembly, further to a dustproof and waterproof LED light.
BACKGROUND OF THE INVENTION
With advantages such as high luminous efficiency, energy saving and long service life, light emitting diode, or LED, has been widely applied. For daily lighting, an LED lamp usually integrates a plurality of power LEDs in order to meet the illumination requirement, and heat dissipation of the LEDs turns out to be an important factor affecting use status and service life of an LED lamp. Consequently, the cooling problem becomes a technological bottleneck impeding extensive application of high-power LED lamps. LED lamps in the prior art are passively cooled down by devices like heat dissipation plates of a heat sink, and the only way to improve the cooling efficiency is to maximize the cooling area. Accordingly, LED lamps in the prior art generally have a large size because of a complicated cooling structure, and yet the cooling efficiency is unsatisfactory. The applicant of the present invention has developed an LED lamp with combined active and passive heat dissipation by integrating a cooling fan with a heat sink, which exhibits excellent cooling efficiency with effectively improved stability and extended service life. However, lamps of very high power such as high bay lights require even better cooling efficiency and therefore usually adopt an open type structure that results in poor waterproof and dustproof effect, impeding their application under outdoor and special environment.
In addition, a thermal silicone grease with a thermal conductivity of 3 W/(m·K)-4 W/(m·K) and a thermal insulating cloth with a thermal conductivity of 2 W(m·K)-3 W/(m·K) are currently used between a light source board and a heat sink for insulation and thermal conduction, both having a rather low thermal conductivity and thus exhibiting rather poor conductive efficiency. A thermal silicone grease is a fluid paste hard to apply evenly, and this will not only lower its thermal conductivity, but also impair the insulation performance between the light source board and the heat sink, or even cause a short circuit between the two. A thermal insulting cloth is also hard to apply evenly as it may be easily deformed, and is not efficient to use as it is hard to place it between the light source board and the heat sink.
SUMMARY OF THE INVENTION
The present invention intends to overcome deficiencies of the prior art and provide a dustproof and waterproof multipurpose LED-light power source assembly that is easy to install and has a high production efficiency as well as great dustproof and waterproof effects.
This invention also provides a dustproof and waterproof LED light with great cooling, waterproof and dustproof effects.
A dustproof and waterproof multipurpose LED-light power source assembly according to the present invention employs the following technical solutions. The dustproof and waterproof multipurpose LED-light power source assembly according to the present invention comprises a heat sink, a cooling fan, a driving circuit board module, an LED light source module, a power supply box top cover, a power supply box bottom cover, and a waterproof bolt assembly. The LED light source module comprises a plurality of LED chips and an LED heat dissipation substrate. The cooling fan is dustproof and waterproof. The heat sink comprises a base plate with which the LED heat dissipation substrate is fixedly connected to conduct heat for dissipation. The base plate has a flat bottom surface and a top surface with a heat dissipation portion of which the central top is provided with a space area for accommodating the cooling fan. The power supply box bottom cover is above the cooling fan and is fixedly connected with the heat sink. The power supply box top cover is sealedly connected with the power supply box bottom cover to enclose the driving circuit board module. The waterproof bolt assembly is connected to the top of the power supply box top cover.
The heat sink has a circular outer contour, the heat dissipation portion comprises a plurality of outer heat dissipation members at the top margin of the base plate and a plurality of inner heat dissipation members at the top center of the base plate, the outer heat dissipation members are sheet-like and are radially arranged along the base plate, air passages are formed between adjacent outer heat dissipation members, and the inner heat dissipation members are needle-like.
A synthetic mica sheet is placed between the LED heat dissipation substrate and the base plate, with an edge exceeding that of the LED heat dissipation substrate by 1-10 mm.
The LED heat dissipation substrate and the base plate are fixed together by a plurality of first screws, and insulating rubber particles are provided where the first screws are used to fix the connection so as to insulate the LED heat dissipation substrate from the first screws and the base plate.
The dustproof and waterproof multipurpose LED-light power source assembly further comprises an insulating annular panel in a space sealedly formed by the power supply box top cover and the power supply box bottom cover, and the driving circuit board module is positioned within the insulating annular panel.
The dustproof and waterproof multipurpose LED-light power source assembly further comprises a lens and a decorative ring, both fixedly connected to the bottom of the heat sink by second screws, and a silicone waterproof gasket is provided where the lens is connected to the bottom of the heat sink.
The inlet and outlet of the cooling fan are respectively provided with a fan net, and a plurality of third screws successively pass through the fan net above the cooling fan, the cooling fan, and the fan net below the cooling fan to get fixedly connected to the heat sink.
The power supply box top cover and the power supply box bottom cover are both round, and a waterproof sealant is applied to the seam between the two.
At least two support columns protruding from the heat dissipation portion are provided on the back of the heat sink to support the power supply box bottom cover, a plurality of bolts having internal threads in the leading end and external threads in the trailing end pass through the power supply box bottom cover to get fixedly connected to the support columns, a plurality of fifth screws pass through the driving circuit board module to get fixedly connected to the internal threads in the leading ends of the bolts, the support column is 10-50 mm higher than the upper surface of the cooling fan, and the leading end of the bolt with internal threads has a height of 5-10 mm.
The dustproof and waterproof LED light according to the present invention employs the following technical solutions. The dustproof and waterproof LED light according to the present invention comprises a dustproof and waterproof multipurpose LED-light power source assembly as well as an air guide housing, a top cover and a power line. The dustproof and waterproof multipurpose LED-light power source assembly comprises a heat sink, a cooling fan, a driving circuit board module, an LED light source module, a power supply box top cover, a power supply box bottom cover, and a waterproof bolt assembly. The LED light source module comprises a plurality of LED chips and an LED heat dissipation substrate. The cooling fan is dustproof and waterproof. The heat sink comprises a base plate with which the LED heat dissipation substrate is fixedly connected to conduct heat for dissipation. The base plate has a flat bottom surface and a top surface with a heat dissipation portion of which the central top is provided with a space area for accommodating the cooling fan. The power supply box bottom cover is above the cooling fan and is fixedly connected with the heat sink. The power supply box top cover is sealedly connected with the power supply box bottom cover to enclose the driving circuit board module. The waterproof bolt assembly is connected to the top of the power supply box top cover. The air guide housing is fixedly connected to the heat sink to enclose in its cavity the cooling fan, the power supply box top cover, the power supply box bottom cover, and the space above the heat sink. The air guide housing is provided with a plurality of air guide apertures on the upper sidewall. The top cover is fixedly connected to the air guide housing to laterally enclose the air guide apertures that communicates with the outside air through an opening around the bottom of the top cover. The power line successively passes through the top cover, the air guide housing and the power supply box top cover to get electrically connected to the driving circuit board module and then passes through the power supply box bottom cover to get electrically connected to the cooling fan and the LED light source module. A waterproof bolt assembly sealedly fixes where the power line passes through the power supply box top cover. A waterproof sealant sealedly fixes where the power line passes through the power supply box bottom cover.
The heat sink has a circular outer contour, the heat dissipation portion comprises a plurality of outer heat dissipation members at the top margin of the base plate and a plurality of inner heat dissipation members at the top center of the base plate, the outer heat dissipation members are sheet-like and are radially arranged along the base plate, air passages are formed between adjacent outer heat dissipation members, and the inner heat dissipation members are needle-like.
A synthetic mica sheet is placed between the LED heat dissipation substrate and the base plate, with an edge exceeding that of the LED heat dissipation substrate by 1-10 mm.
The LED heat dissipation substrate and the base plate are fixed together by a plurality of first screws, and insulating rubber particles are provided where the first screws are used to fix the connection so as to insulate the LED heat dissipation substrate from the first screws and the base plate.
The dustproof and waterproof multipurpose LED-light power source assembly further comprises an insulating annular panel in a space sealedly formed by the power supply box top cover and the power supply box bottom cover, and the driving circuit board module is positioned within the insulating annular panel.
The dustproof and waterproof multipurpose LED-light power source assembly further comprises a lens and a decorative ring, both fixedly connected to the bottom of the heat sink by second screws, and a silicone waterproof gasket is provided where the lens is connected to the bottom of the heat sink.
The inlet and outlet of the cooling fan are respectively provided with a fan net, and a plurality of third screws successively pass through the fan net above the cooling fan, the cooling fan, and the fan net below the cooling fan to get fixedly connected to the heat sink.
The power supply box top cover and the power supply box bottom cover are both round, and a waterproof sealant is applied to the seam between the two.
At least two support columns protruding from the heat dissipation portion are provided on the back of the heat sink to support the power supply box bottom cover, a plurality of bolts having internal threads in the leading end and external threads in the trailing end pass through the power supply box bottom cover to get fixedly connected to the support columns, a plurality of fifth screws pass through the driving circuit board module to get fixedly connected to the internal threads in the leading ends of the bolts, the support column is 10-50 mm higher than the upper surface of the cooling fan, and the leading end of the bolt with internal threads has a height of 5-10 mm.
The dustproof and waterproof LED light further comprises a transparent protective casing and a lampshade, both of which are fixedly connected to the bottom of the heat sink to enclose the LED light source module. The skirt of the bottom of the transparent protective casing caps the margin of the bottom of the lampshade so that the transparent protective casing and the lampshade can be connected to the heat sink by bolts. A waterproof sealant is applied to the seam between the skirt of the bottom of the transparent protective casing and the heat sink.
The present invention has advantageous effects as below. The dustproof and waterproof multipurpose LED-light power source assembly according to this invention comprises a heat sink, a cooling fan, a driving circuit board module, an LED light source module, a power supply box top cover, a power supply box bottom cover and a waterproof bolt assembly, the LED light source module comprising a plurality of LED chips and an LED heat dissipation substrate, the cooling fan being dustproof and waterproof, the heat sink comprising a base plate with which the LED heat dissipation substrate is fixedly connected to conduct heat for dissipation, the base plate having a flat bottom surface and a top surface with a heat dissipation portion, of which the central top is provided with a space area for accommodating the cooling fan, the power supply box bottom cover being above the cooling fan and being fixedly connected with the heat sink, the power supply box top cover being sealedly connected with the power supply box bottom cover to enclose the driving circuit board module, and the waterproof bolt assembly being connected to the top of the power supply box top cover. On account of the above, a power supply portion insulated from dust and water is obtained in the present invention by means of sealedly connecting the power supply box top cover with the power supply box bottom cover to enclose the driving circuit board module, connecting a waterproof bolt assembly to the top of the power supply box top cover, and sealing the power line with the waterproof bolt assembly, and a fan portion insulated from dust and water is also obtained by using a cooling fan that is dustproof and waterproof, thereby sealing and insulating the whole light power supply assembly from water and dust. The light power supply assembly rid of risks such as insects entering the power supply portion can be used as a primary element in street lamps, ceiling lamps, downlights, or high bay lights for outdoor lighting or locations like dusty workshops and plants. Heat dissipation of the lamp is combined with active and passive cooling by integrating the cooling fan with the heat sink, which is highly efficient and helps to effectively improve stability of the lamp and extend service life of the lamp. To sum up, the present invention is easy to install and has a high production efficiency as well as great dustproof and waterproof effects, and thus can be used in many ways.
A synthetic mica sheet is placed between the LED heat dissipation substrate and the base plate, with an edge exceeding that of the LED heat dissipation substrate by 1-10 mm. The synthetic mica sheet is a sheet-like insulating material produced by pressing mica papers made of mica raw materials together with adhesives under high temperature and high pressure. The synthetic mica sheet is excellent in thermal conductivity, flame resistance and electric insulation with advantages such as uniform thickness, adjustable area, and great flexibility and workability. It has a thermal conductivity of 5 W/(m·K)-24 W/(m·K), which is higher than that of a thermal silicone grease or a thermal insulating cloth. Besides, the mica sheet has a fixed shape and a high average uniformity, so it contacts with the LED heat dissipation substrate and the base plate in a tighter and more uniform way, and has a better thermal conductivity and a better insulativity. Further, the mica sheet is easy to install and has a high production efficiency. With the edge of the mica sheet exceeding the edge of the LED heat dissipation substrate by 1-10 mm, the requirement for creepage distance between LED heat dissipation substrate and the heat sink is met for safety. In conclusion, this invention has great thermal conductivity and insulativity.
For the same reasons, the dustproof and waterproof LED light according to the present invention has great cooling, waterproof and dustproof effects.
BRIEF DESCRIPTION OF DRAWINGS
These and other features and advantages of the present invention will become more readily appreciated when considered in connection with the following detailed description and appended drawings, wherein like designations denote like elements in the various views, and wherein:
FIG. 1 is a three-dimensional structure diagram of a dustproof and waterproof multipurpose LED-light power source assembly implementing the present invention;
FIG. 2 is an exploded diagram of the dustproof and waterproof multipurpose LED-light power source assembly;
FIG. 3 is a cross-section diagram of the dustproof and waterproof multipurpose LED-light power source assembly;
FIG. 4 is a cross-section diagram of the heat sink and light source portion of the dustproof and waterproof multipurpose LED-light power source assembly;
FIG. 5 is a partially enlarged diagram of I shown in FIG. 4 ;
FIG. 6 is a partially enlarged diagram of II shown in FIG. 4 ;
FIG. 7 is a three-dimensional structure diagram of a dustproof and waterproof LED light implementing the present invention;
FIG. 8 is an exploded diagram of the dustproof and waterproof LED light;
FIG. 9 is a cross-section diagram of the dustproof and waterproof LED light;
FIG. 10 is a three-dimensional structure diagram of the heat sink of the dustproof and waterproof LED light; and
FIG. 11 is a three-dimensional structure diagram of the heat sink shown in FIG. 10 at a different angle.
DETAILED DESCRIPTION OF THE INVENTION
As shown in FIG. 1 to FIG. 6 , the dustproof and waterproof multipurpose LED-light power source assembly according to the embodiment comprises a heat sink 1 , a cooling fan 2 , a driving circuit board module 3 , an LED light source module 4 , an insulating annular panel 30 , a power supply box top cover 31 , a power supply box bottom cover 32 , a lens 5 , a decorative ring 6 , a synthetic mica sheet ( 8 ), and a waterproof bolt assembly 34 , wherein the LED light source module 4 comprises a plurality of LED chips and an LED heat dissipation substrate; the cooling fan 2 is dustproof and waterproof; the heat sink 1 has a circular outer contour, and comprises a base plate 101 with a round flat bottom surface and a top surface having a heat dissipation portion of which the central top is provided with a space area for accommodating the cooling fan 2 ; the heat dissipation portion comprises a plurality of outer heat dissipation members 102 in the top margin of the base plate 101 and a plurality of inner heat dissipation members 103 in the top center of the base plate 101 , the outer heat dissipation members 102 being sheet-like and being radially arranged along the base plate 101 with air passages formed between adjacent outer heat dissipation members 102 while the inner heat dissipation members ( 103 ) being needle-like to increase cooling channels and improve heat dissipation; the inlet and outlet of the cooling fan 2 are respectively provided with a fan net 21 to proof the fan, in a specific connection mode where four third screws 93 successively pass through the fan net 21 above the cooling fan 2 , the cooling fan 2 , and the fan net 21 below the cooling fan 2 to get fixedly connected to the heat sink 1 ; the power supply box top cover 31 and the power supply box bottom cover 32 are both round in accordance with the outer contour of the heat sink 1 ; the power supply box top cover 31 is sealedly connected to the power supply box bottom cover 32 to enclose the driving circuit board module 3 , and a waterproof sealant is applied to the seam between the power supply box top cover 31 and the power supply box bottom cover 32 which are connected specifically by four fourth screws 94 and four nuts 97 ; the insulating annular panel 30 is positioned in a space sealedly formed by the power supply box top cover 31 and the power supply box bottom cover 32 , and the driving circuit board module 3 is positioned within the insulating annular panel 30 , so that the power driving portion is insulated from the power supply box top cover 31 and the power supply box bottom cover 32 in a better way; the waterproof bolt assembly 34 is connected to the top of the power supply box top cover 31 ; the power supply box bottom cover 32 is positioned above the cooling fan 2 and is fixedly connected to the heat sink 1 , four support columns 105 protruding from the heat dissipation portion are provided on the back of the heat sink 1 to support the power supply box bottom cover 32 , the support column 105 is 10-50 mm higher than the upper surface of the cooling fan 2 so that the power supply box bottom cover 32 is spaced from the cooling fan 2 , and air circulation at the input and output of the fan is enhance in a specific connection mode where four bolts 96 having internal threads in the leading end and external threads in the trailing end pass through the power supply box bottom cover 32 to get fixedly connected to the support columns 105 , four fifth screws 95 pass through the driving circuit board module 3 to get fixedly connected to the internal threads in the leading ends of the bolts 96 , an insulation treatment is conducted where the fifth screw 95 passes through the driving circuit board module 3 , and the leading end of the bolt 96 with internal threads has a height of 5-10 mm to meet the requirements for insulation and creepage distance between the driving circuit board module 3 and the power supply box bottom cover 32 ; the LED heat dissipation substrate is fixedly connected with the base plate 101 to conduct heat for dissipation, in a specific way that the LED heat dissipation substrate and the base plate 101 are fixed together by four first screws 91 , insulating rubber particles 7 are provided where the first screws 91 are used to fix the connection to insulate the LED heat dissipation substrate from the first screws 91 and the base plate 101 so that the insulation is enhanced and the creepage distance is increased for safety requirements, and a synthetic mica sheet 8 is placed between the LED heat dissipation substrate and the base plate 101 , with an edge exceeding that of the LED heat dissipation substrate by 1-10 mm; and the decorative ring 6 and the lens are fixedly connected to the bottom of the heat sink 1 specifically by second screws 92 with a silicone waterproof gasket 9 provided where the lens 5 is connected to the bottom of the heat sink 1 , so as to further improve waterproof performance of the light source portion.
In the dustproof and waterproof multipurpose LED-light power source assembly according to the present invention, the power supply box top cover 31 is sealedly connected with the power supply box bottom cover 32 to enclose the driving circuit board module 3 , and the waterproof bolt assembly 34 is connected to the top of the power supply box top cover 31 , therefore the power line can be sealed by the waterproof bolt assembly 34 to proof the power supply portion against dust and water; in addition, the fan portion is insulated from dust and water as the cooling fan is dustproof and waterproof; the light source portion is also dustproof and water proof by fixedly connecting the decorative ring and the lens to the bottom of the heat sink; thereby the dustproof and waterproof multipurpose LED-light power source assembly, as a whole, is insulated from water and dust, and can be used as a primary element in street lamps, ceiling lamps, downlights, or high bay lights for outdoor lighting or locations like dusty workshops and plants. Heat dissipation of the lamp is combined with active and passive cooling by integrating the cooling fan 2 with the heat sink 1 , which is highly efficient and helps to effectively improve stability of the lamp and extend service life of the lamp. The synthetic mica sheet is placed between the LED heat dissipation substrate and the base plate 101 , which is a sheet-like insulating material produced by pressing mica papers made of mica raw materials together with adhesives under high temperature and high pressure. The synthetic mica sheet is excellent in thermal conductivity, flame resistance and electric insulation with advantages such as uniform thickness, adjustable area, and great flexibility and workability. It has a thermal conductivity of 5 W/(m·K)-24 W/(m·K), which is higher than that of a thermal silicone grease or a thermal insulating cloth. Besides, the mica sheet has a fixed shape and a high average uniformity, and contacts with the LED heat dissipation substrate and the base plate 101 in a tighter and more uniform way, so it has a better thermal conductivity and a better insulativity, and is easy to install with a high production efficiency. With the edge of the mica sheet 8 exceeding the edge of the LED heat dissipation substrate by 1-10 mm, the requirement for creepage distance between the LED heat dissipation substrate and the heat sink 1 is met for safety. To sum up, the dustproof and waterproof multipurpose LED-light power source assembly according to the present invention is easy to install and has a high production efficiency, great thermal conductivity and insulativity as well as excellent dustproof and waterproof effects, and thus can be used in many ways.
When the dustproof and waterproof multipurpose LED-light power source assembly according to the present invention works for lighting, the cooling fan 2 works simultaneously, the heat generated from the radiant LED chips is conducted to the heat sink 1 through the LED heat dissipation substrate and the synthetic mica sheet 8 , the heat sink 1 dissipates part of the heat into the air in the same way that a heat sink of the prior art is passively cooled, and at the same time, the cooling fan 2 functions to force the ambient air to flow through the heat sink 1 and carry off the heat. Heat dissipation in such a way has an excellent effect, by which the LED chips are prevented from operating at high temperatures in favor of longer service lives. Existence of forced cooling allows the heat sink 1 to have a reduced size and weight, and makes the lamp more applicable.
As FIG. 7 to FIG. 11 shows, the dustproof and waterproof LED light according to the embodiment comprises an LED light source module 4 , a driving circuit board module 3 , a heat sink 1 , a cooling fan 2 , an air guide housing 40 , a power supply box top cover 31 , a power supply box bottom cover 32 , a top cover 45 , a transparent protective casing 47 , a reflector 48 , a lampshade 49 , and a power line 33 ; the LED light source module 4 comprises a plurality of LED chips and an LED heat dissipation substrate; the reflector 48 is positioned in front of the light emitting part of the LED light source module 4 and comprises a plurality of reflective surfaces corresponding to the LED chips; the LED heat dissipation substrate contacts with the heat sink 1 and conducts heat for dissipation; the power supply box bottom cover 32 is positioned above the cooling fan 2 and is fixedly connected to the heat sink 1 ; the power supply box top cover 31 and the power supply box bottom cover 32 are both round in accordance with the outer contour of the heat sink 1 ; the power supply box top cover 31 is sealedly connected with the power supply box bottom cover 32 to enclose the driving circuit board module 3 with a waterproof sealant applied to the seam between the two; the air guide housing 40 is fixedly connected to the heat sink 1 to enclose in its cavity the cooling fan 3 , the power supply box top cover 31 , the power supply box bottom cover 32 and the space above the heat sink 1 ; the air guide housing 40 is provided with a plurality of air guide apertures 41 on the upper sidewall, the top cover 45 is fixedly connected to the air guide housing 40 to laterally enclose the air guide apertures 41 that communicates with the outside air through an opening around the bottom of the top cover 45 , so that the air flow is guided, flow passages are increased and heat dissipation is improved; the power line 33 successively passes through the top cover 45 , the air guide housing 40 and the power supply box top cover 31 to get electrically connected to the driving circuit board module 3 and then passes through the power supply box bottom cover 32 to get electrically connected to the cooling fan 2 and the LED light source module 4 ; a waterproof bolt assembly 34 sealedly fixes where the power line 33 passes through the power supply box top cover 31 ; a waterproof sealant sealedly fixes where the power line 33 passes through the power supply box bottom cover 32 ; the cooling fan 2 is dustproof and waterproof; the transparent protective casing 47 and the lampshade 49 are fixedly connected to the bottom of the heat sink 1 to enclose the LED light source module 4 ; a waterproof sealant is applied to the seam between the skirt of the bottom of the transparent protective casing 47 and the heat sink 1 to proof the LED light source module 4 in the transparent protective casing 47 against water and dust; the skirt of the bottom of the transparent protective casing 47 caps the margin of the bottom of the lampshade 49 , and the transparent protective casing 47 and the lampshade 49 is connected to the heat sink 1 by bolts; the heat sink 1 has a circular outer contour, and comprises a base plate 101 with a round flat bottom surface and a top surface having a heat dissipation portion of which the central top is provided with a space area for accommodating the cooling fan 2 , the heat dissipation portion comprising a plurality of outer heat dissipation members 102 in the top margin of the base plate 101 and a plurality of inner heat dissipation members 103 in the top center of the base plate 101 , the outer heat dissipation members 102 being sheet-like and being radially arranged along the base plate 101 with air passages formed between adjacent ones while the inner heat dissipation members ( 103 ) being needle-like with crisscrossing air flow channels formed among them in favor of great heat dissipation; a plurality of first connecting posts 105 and second connecting posts 104 are provided on the base plate 101 of the heat sink 1 ; the driving circuit board module 3 and the power supply box bottom cover 32 are successively connected to the first connecting posts 105 by bolts; the air guide housing 40 is connected to the second connecting posts 104 by bolts; and the power supply box top cover 31 is connected to the power supply box bottom cover 32 by bolts, the same way as the top cover 45 is connected to the air guide housing 40 .
In the dustproof and waterproof LED light according to this invention, the power supply box top cover 31 is sealedly connected with the power supply box bottom cover 32 to enclose the driving circuit board module 3 , the waterproof bolt assembly 34 sealedly fixes where the power line 33 passes through the power supply box top cover 31 , and a waterproof sealant sealedly fixes where the power line 33 passes through the power supply box bottom cover 32 , so that the driving circuit board module 3 is sealed by the power supply box top cover 31 and the power supply box bottom cover 32 so as to become waterproof and dustproof; moreover, the cooling fan 2 is waterproof; thereby the power supply portion of the whole lamp is sealed and insulated from water and dust, and is rid of risks such as entering of insects; and thus the lamp can be used outdoors or for locations like dusty workshops and plants. Heat dissipation of the lamp is combined with active and passive cooling by integrating the cooling fan 2 with the heat sink 1 , which is highly efficient and helps to effectively improve stability of the lamp and extend service life of the lamp. In a word, the present invention has great cooling and waterproof effects and can be applied for indoor or outdoor high bay lights.
When the dustproof and waterproof LED light according to the present invention works for lighting, the cooling fan 2 works simultaneously, the heat generated from the radiant LED chips is conducted to the heat sink 1 through the LED heat dissipation substrate, and the heat sink 1 conducts part of the heat to the lampshade 49 and directly or indirectly dissipates the heat into the air in the same way that a heat sink of the prior art is passively cooled. In the meantime, by the action of the cooling fan 2 , ambient air enters the cavity of the air guide housing 40 via the air guide apertures 41 , flows from the inner heat dissipation members 103 to the outer heat dissipation members 102 , and flows outside through the gap at the bottom of the heat sink 1 . The heat of the heat sink 1 is taken away thanks to the air circulation forced by the cooling fan 2 , and heat dissipation in such a way has an excellent effect, by which the LED chips are prevented from operating at high temperatures in favor of longer service lives. Existence of forced cooling allows the heat sink 1 to have a reduced size and weight, and makes the lamp more applicable.
This invention can be widely used in the field of LED lighting. | A dustproof and waterproof multipurpose LED-light power source assembly comprises a heat sink, a heat-dispersal fan, a circuit board driver module, an LED light source module, a power-source casing top cover and a power-source casing bottom cover. The LED light source module comprises plural LED chips and an LED heat-dispersing substrate. The heat-dispersal fan is a dustproof and waterproof fan. The heat sink comprises a baseboard to which the LED heat-dispersing substrate is fixedly connected and conducts dispersed heat. At the center of the top of a heat-dispersal member, a space is provided to accommodate the heat-dispersal fan. The power-source casing bottom cover is positioned above the heat-dispersal fan and is fixedly connected to the heat sink. The power-source casing top cover and the power-source casing bottom cover are hermetically connected one to the other. A waterproof bolt assembly is connected to the top of the power-source casing top cover. | 5 |
CROSS-REFERENCE INFORMATION
Cross Reference to Related Application
[0001] This application is a Continuation of U.S. patent application Ser. No. 12/827,555, filed Jun. 30, 2010, which is a Continuation of U.S. patent application Ser. No. 12/349,373, filed Jan. 6, 2009, now U.S. Pat. No. 7,751,036, which is a Continuation of U.S. patent application Ser. No. 11/488,622, filed Jul. 19, 2006, now U.S. Pat. No. 7,474,394, which claims priority from Japanese Patent Application No. 2005-209384, filed in Japan on Jul. 20, 2005, the contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to defect inspection apparatus and a defect inspection method which are used in a manufacturing line of a semiconductor device, liquid crystal device, magnetic head or the like, and particularly relates to a calculation technique of size of a detected defect.
[0003] Inspection of a semiconductor wafer is described as an example.
[0004] In a semiconductor manufacturing process in the related art, foreign substances on a semiconductor substrate (wafer) may cause inferiority such as imperfect insulation or a short circuit. When a fine foreign substance exists in a semiconductor substrate of a semiconductor element which is significantly miniaturized, the foreign substance may cause imperfect insulation of a capacitor or breakdown of a gate oxide film. The foreign substances may be contaminated in various ways due to various reasons, such as contamination from a movable portion of a carrier device, contamination from a human body, contamination from reaction of a process gas in treatment equipment, and previous contamination in chemicals or materials. Similarly, in a manufacturing process of a liquid crystal display device, contamination of a foreign substance on a pattern, or formation of some defects disables the device as a display device. The same situation occurs in a manufacturing process of a printed circuit board, that is, contamination of the foreign substance leads to a short circuit of a pattern or imperfect connection.
[0005] It is now increasingly important to detect a defect such as foreign substance causing inferior products and take the measure for causes of the defect and thus keep a certain yield of products for stably producing a semiconductor element or a flat display device represented by the liquid crystal display device, which are expected to be further miniaturized even more in the future.
[0006] To keep the yield of products, it is necessary to determine whether a detected defect such as foreign substance has influence on the yield or not, and it is important to obtain information of a position where the defect such as foreign substance was detected, and information of size of the detected defect.
[0007] As a technique for calculating size of a defect detected by defect inspection apparatus, as described in JP-A-5-273110, a method is disclosed, in which a laser beam is irradiated to an object, and then scattering light from a particle on the object or a crystal defect therein is received and then subjected to image processing, thereby size of the particle or the crystal defect is measured. In “Yield Monitoring and Analysis in Semiconductor Manufacturing” mentioned in digest of ULSI technical seminar, pp 4-42 to 4-47 in SEMIKON Kansai in 1997, a yield analysis method using a defect by a foreign substance detected on a semiconductor wafer is disclosed.
SUMMARY OF THE INVENTION
[0008] As described above, inspection apparatus in the related art for various fine patterns including a pattern in a semiconductor device is now hard to satisfy detection accuracy of defect size required for detection of a defect on an increasingly miniaturized pattern. Therefore, it is desirable to accurately calculate size of a detected defect.
[0009] Defect inspection apparatus according to embodiments of the invention includes a unit for classifying defects into a plurality of classes based on feature quantity of the defects at detection, and modifying a size calculation method of a defect for each of classes.
[0010] That is, in embodiments of the invention, defect detection apparatus for detecting a defect of an object is configured to have an illumination unit for illuminating light to the object; a detection unit for detecting scattering light from the object; a defect detection unit for detecting the defect by processing a detection signal of the scattering light detected by the detection unit; a size measuring unit for calculating size of the defect detected by the defect detection unit; a size correction unit for correcting the size of the defect detected by the size measuring unit depending on separately obtained information of feature quantity or a type of the defect; a data processing unit for processing a result corrected by the size correction unit; and a display unit for displaying information of a result processed by the data processing unit.
[0011] According to embodiments of the invention, size of a detected defect can be accurately calculated, and for example, only defects having a size larger than a size to be managed can be extracted in semiconductor manufacturing. Thus, since a defect having higher influence on a production yield can be preferentially managed, productivity is improved in semiconductor manufacturing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] These 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.
[0013] FIG. 1 is a block diagram showing a schematic configuration of defect inspection apparatus according to embodiments of the invention;
[0014] FIGS. 2A to 2B are graphs showing examples of defect detection signals, wherein FIG. 2A shows a case of large signal intensity, and FIG. 2B shows a case of small signal intensity;
[0015] FIGS. 3A to 3B are views showing processing for each region, wherein FIG. 3A shows an example of dividing the inside of a die (chip), and FIG. 3B shows an example of dividing a front face of a wafer;
[0016] FIGS. 4A to 4B are scatter diagrams of defect size, wherein FIG. 4A shows an example of large dispersion, and FIG. 4B shows an example of small dispersion;
[0017] FIGS. 5A to 5B are views showing examples of representative values of defect size, wherein FIG. 5A shows an example of X or Y size, and FIG. 5B shows an example of L size;
[0018] FIG. 6 is a flowchart of setting a correction factor of size calculation;
[0019] FIG. 7 is a flowchart of inspection and output;
[0020] FIGS. 8A to 8C are views showing examples of size correction using defects of which the size is known, wherein FIG. 8A shows a condition that the defects of which the size is known are disposed on a wafer, FIG. 8B shows a condition that size measured by SEM does not comparatively correspond to size detected and calculated by the defect inspection apparatus in a scatter diagram of defect size, and FIG. 8C shows a condition that the calculated size comparatively corresponds to the size measured by SEM by changing a slope of a graph by changing a factor when size of a defect detected by the defect inspection apparatus is calculated, in the scatter diagram of defect size;
[0021] FIG. 9 is a flowchart of calculating a correction factor of size;
[0022] FIGS. 10A to 10C are views showing correction examples when a defect signal is saturated, wherein FIG. 10A is a graph showing a condition that the defect signal is not saturated, FIG. 10B is a graph showing a condition that the defect signal is saturated, and FIG. 10C is a view showing a method of predicting a peak value of a signal when a detection signal is saturated;
[0023] FIGS. 11A to 11B are scatter diagrams of defect size, wherein FIG. 11A shows a condition that size measured by SEM does not comparatively correspond to size detected and calculated by the defect inspection apparatus, and FIG. 11B shows a condition that size, which was calculated with performing correction to a defect detected by the defect inspection apparatus based on feature quantity of the defect, comparatively corresponds to the value measured by SEM;
[0024] FIG. 12 is a block diagram showing a relationship between a manufacturing process and inspection apparatus;
[0025] FIG. 13 is a graph showing a relationship between yield and the number of detected defects;
[0026] FIGS. 14A to 14B are graphs showing examples of a method of extracting a defect signal and feature quantity, wherein FIG. 14A shows a case of using a threshold obtained by a normal threshold setting method, and FIG. 14B shows a case of setting a threshold lower than a normal threshold;
[0027] FIG. 15 is a front view of a display screen showing a screen display example of the defect inspection apparatus; and
[0028] FIGS. 16A to 16B are view of an example of an illumination optical system, wherein FIG. 16A is a front view, and FIG. 16B is a side view.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0029] FIG. 1 shows an example of a configuration of inspection apparatus according to embodiments of the invention (hereinafter, mentioned as defect inspection apparatus).
[0030] The defect inspection apparatus is configured to have an illumination system 100 , a stage system 200 , a detection system 300 , a Fourier transform surface observation system 500 , a signal processing section 400 , an observation optical system 600 , and a control section 2 .
[0031] Defect detection using the defect inspection apparatus shown in FIG. 1 is performed according to the following procedure. The illumination system 100 illuminates a wafer 1 set in the stage system 200 , and the detection system 300 acquires an image of the illuminated wafer 1 . The illumination system 100 adjusts output of a light source 101 by an illumination controller 103 according to an instruction value of the control section 2 . As the light source 101 , a laser light source is used, which emits laser in an ultraviolet region having a wavelength of 400 nm or less. The illumination system 100 includes a unit (not shown) for reducing coherency of the laser emitted from the laser light source. Illumination light is shaped into an appropriate form on the wafer 1 by an optical system 102 . The stage system 200 includes a rotation stage 201 , a Z stage 202 , an X stage 203 , and a Y stage 204 , and moves with respect to the detection system 300 so that the detection system 300 can scan the whole surface of the wafer 1 .
[0032] The detection system 300 includes a Fourier transform lens 301 , spatial filter 302 , focusing lens 303 , and sensor 304 . Here, the spatial filter 302 is to shield a diffraction light pattern caused by diffraction light from a repetitive pattern on the wafer 1 , and set on the Fourier transform surface of the Fourier transform lens 301 . A light shielding pattern of the spatial filter 302 is set such that a diffraction pattern of the wafer 1 is shielded, the diffraction pattern being observed by the Fourier transform surface observation system 500 having a structure that can be inserted and removed into/from an optical path of the detection system 300 . That is, the system 500 is inserted into an optical path of the detection system 300 while removing the spatial filter 302 , and then the optical path is branched by a beam splitter 501 , and an image on the Fourier transform surface of the Fourier transform lens 301 is taken by a camera 503 via a lens 502 and observed. The light shielding pattern of the spatial filter 302 can be set for each type of an object or each of steps. The light shielding pattern of the spatial filter 302 may be fixed during wafer scan, or may be changed in real time depending on a region under scanning.
[0033] An image acquired by the detection system 300 is subjected to AD conversion and then transferred to the signal processing section 400 , wherein the image is processed to detect a defect. The defect inspection apparatus further includes CPU 2 , a display device 3 , an input unit 4 , and a storage device 5 , thereby it can set any optional condition for inspection, and can store and display an inspection result or an inspection condition. Moreover, the defect inspection apparatus can be connected to a network 6 , thereby the inspection result, layout information of the wafer 1 , a lot number, the inspection condition, or an image of a defect observed by an observation device or data of a defect type can be shared over the network 6 . Moreover, the defect inspection apparatus includes the wafer observation system 600 in order to allow observation of the detected defect or an alignment mark integrally formed on the wafer 1 for alignment of a pattern formed on the wafer 1 . Furthermore, while not shown, it includes an automatic focusing unit, so that a region where an image is taken in using a sensor when the wafer is scanned on the stage system 200 is within the depth of focus of the detection system 300 .
[0034] FIGS. 2A to 2B show three-dimensional display of examples of signal detection of two types of defects A and B respectively. FIGS. 2A to 2B exemplify defects having different signal intensity detected by the defect inspection apparatus while having the same size. A vertical direction represents signal intensity, showing intensity for each pixel. Even if defects (foreign substances) have the same size in SEM (scanning electron microscope) observation, detection signals in the defect inspection apparatus may be varied depending on a defect type, defect position, and surface pattern or surface material of the wafer 1 . Thus, size of defects obtained through detection by the defect inspection apparatus according to embodiments of the invention are corrected based on information of the defect type, defect position, and surface pattern or surface material of the wafer 1 , thereby size calculation accuracy of defects can be improved.
[0035] Moreover, to improve the size calculation accuracy of a defect, it is important to modify a detection condition depending on a position of the defect. Thus, in the defect inspection apparatus according to embodiments of the invention, grouping is carried out depending on fineness of a pattern in a detection portion of the wafer 1 or each of many dies (chips) formed on the wafer 1 , so that a detection condition of the defect can be modified.
[0036] FIGS. 3A to 3B show examples of grouping for each of regions in the wafer or die (chip). FIG. 3A shows an example of grouping the inside of the die depending on a type of a circuit pattern. A reference 3001 shows a region where a wiring pattern is random in the die, and a reference 3002 shows a region where the wiring pattern is repeated at a constant pitch. FIG. 3B shows an example of grouping of the whole surface of the wafer 1 . A reference 3003 indicates a central portion of the wafer 1 , and a reference 3004 indicates the outer circumferential portion of the wafer. A reference 3005 indicates a die. In the case of a fine pattern, interference of illumination light may occur due to a pattern near a defect and the defect, and thus a detection signal of a defect may be different from that in the case of detecting a defect near a coarse pattern, and therefore grouping is carried out depending on regions. Moreover, when thickness is uneven in a wafer surface due to deposition, etching, or polishing, since a detection signal of a defect may be varied due to interference of light as well, grouping is carried out.
[0037] FIGS. 4A to 4B show an evaluation method of dimension accuracy of a defect. A graph is displayed on a screen, in which measured values of size by defect observation apparatus such as SEM are plotted as a horizontal axis, and calculated values of size by the defect inspection apparatus are plotted as a vertical axis, which allows visual expression of calculation accuracy of defect size. FIG. 4A shows an example of large dispersion of defect distribution, that is, low dimension accuracy. FIG. 4B shows an example of small dispersion of defect distribution compared with the example of FIG. 4A , that is, high dimension accuracy.
[0038] FIGS. 5A to 5B are views for illustrating a way of defining a measured value when defect size is measured by the defect observation device such as SEM. X and Y are coordinate axes used in observation of a defect by SEM. In a way of expressing the defect size, projected length in an X-axis direction (X size), projected length in an Y-axis direction (Y size), diameter of a circumscribed circle of a defect (L; major axis size), √(X+Y), or √(X 2 +Y 2 ) can be used as a representative value. In yield management, one of the diameter of the circumscribed circle of the defect (L; major axis size), √(X+Y), and √(X 2 +Y 2 ), or a combination of them is used.
[0039] FIG. 6 shows a condition setting flow for correcting size of a defect detected by the defect inspection apparatus. In embodiments of the invention, a correction factor that was determined and stored according to the flow of FIG. 6 is used, and size of a defect on the wafer, which was inspected and detected by the defect inspection apparatus according to a flow shown in FIG. 7 , is calculated, and then inspection data added with size is registered into a defect management server.
[0040] A flow of FIG. 6 is described below. Inspection is performed using the defect inspection apparatus in S 601 , and defects to be observed by the defect observation apparatus such as SEM are selected from defects detected using the defect inspection apparatus in S 602 . When the number of defects is small, for example, about 100, the whole number of them may be selected. When the number of defects is large, while they may be randomly extracted, if defects to be observed are extracted using SSA (Spatial Signature Analysis) based on a distribution condition in a wafer plane, several types of defects in a wafer can be evenly extracted. After defects as objects are selected in S 602 , size or a type (convex defect, concave defect, planar defect or the like) of the defect as object selected by the defect observation apparatus such as SEM is obtained in S 603 . After that, based on information of the size or type of the defect, a size calculation result of the defect inspection apparatus is compared with a measurement result of the defect observation apparatus such as SEM to create a scatter diagram as shown in FIG. 4 in S 604 , then a correction factor is determined depending on the size or type of the defects in S 605 , and then stored in S 606 .
[0041] Comparison between the size calculation result of the defect inspection apparatus and the measurement result of the defect observation apparatus such as SEM in S 604 can be carried out by the defect inspection apparatus, SEM, a separated personal computer or the like. Since creation of the scatter diagram in S 604 is intended to be for reference when a user adjusts a condition, in the case that the correction factor is automatically calculated, it need not always be shown diagrammatically. In correction in S 605 , linear correction (y=ax+b): (x is defect size calculated by the defect inspection apparatus, y is size after correction, a is a correction factor, and b is an offset value) may be used, or a higher-order transformation equation may be used for the correction. Regarding a way of determining the correction factor a or the offset value b, one of a value previously registered into the defect inspection apparatus, a value adapted for each treatment step in wafer manufacturing, and a value corresponding to a defect type or feature quantity of a defect, or a combination of them may be used.
[0042] After the correction factor has been calculated in S 605 , the correction factor is stored in S 606 , consequently condition setting for size calculation is completed.
[0043] FIG. 7 shows a flow of inspection and output. A wafer is inspected (S 701 ), then classification of defects is performed based on a defect type or feature quantity of a defect (S 702 ). Defect size is calculated in S 703 , and then size is corrected for each defect class using the correction factor previously set according to the flow described using FIG. 6 in S 704 . A size calculation result S 705 after correction is added to the defect detection result, then data of them are transferred to a defect management server (S 706 ).
[0044] FIGS. 8A to 8C show a method of size calibration using a defect having known size. FIG. 8A shows a standard wafer in which the defects having known size are integrally formed, or a product wafer, dummy wafer, or mirror wafer on which standard particles are scattered, wherein defects 901 (size A (nm)), 902 (size B (nm)), and 903 (size C (nm)) having known size are integrally formed.
[0045] FIG. 8B shows an aspect that the size detected and calculated by the defect detection apparatus is different from the size measured by SEM depending on a surface condition or surface material of a wafer due to an adjustment condition of the defect detection apparatus or difference in machine, indicating a relationship between actual size of the defects 901 , 902 and 903 having known size, which were measured using SEM, and size of the defects detected and calculated by the defect detection apparatus. A reference 904 indicates an approximate curve. Based on the approximate curve of 904 , a factor in size calculation is changed so that a slope of a graph is corrected to be approximately 45 degrees ( FIG. 8C ), thereby a value of the defect size detected and calculated by the defect detection apparatus can be calibrated.
[0046] FIG. 9 shows a flow of obtaining a factor for correcting size. First, a wafer is inspected to detect a defect using the defect inspection apparatus according to embodiments of the invention (S 901 ), then a sum signal of detection signals in the whole region of the detected defect is calculated (S 902 ). Since part of the detected defects may be beyond a dynamic range of the sensor 304 , saturating signal correction (S 903 ) is performed, and size is temporarily calculated (S 904 ). In this time point, since the calculated size may be different from actual size measured by SEM, an approximate formula is then calculated (S 905 ), and then a correction factor is calculated according to the approximate formula (S 906 ). For correction, linear correction (y=ax+b): (x is defect size calculated by the defect inspection apparatus, y is size after correction, a is a correction factor, and b is an offset value) may be used, or a higher-order transformation equation may be used.
[0047] FIGS. 10A to 10C show a specific example of the saturating signal correction of the step S 903 in FIG. 9 . FIG. 10A shows an example of a defect of which the signal is not saturated, wherein d 01 indicates a signal peak. FIG. 10B shows signal intensity (d 02 ) of a defect of which the signal is partially beyond a dynamic range of a sensor during detection of a defect signal and thus saturated. As shown in FIG. 100 , a portion where a defect signal is lacked because of saturation is approximated by an appropriate function, so that a signal of a lacked portion is estimated, thereby a saturating signal can be corrected. For example, when a defect signal is approximated by Gaussian curve, a value of the number of saturated pixels (d 03 ) and broadening of Gaussian distribution (standard deviation) are supposed, thereby a peak (d 04 ) of the defect signal can be estimated.
[0048] FIGS. 11A to 11B show correction based on feature quantity of a defect. A correction factor is obtained according to a procedure shown in FIG. 6 for each defect type (convex defect, concave defect, planar defect or the like), then a correction factor of defect size is modified based on feature quantity of a defect according to a procedure of FIG. 7 , thereby dimension accuracy can be improved. FIG. 11A is a scatter diagram of defect size, showing a condition that size measured by SEM does not comparatively correspond to size detected and calculated by the defect inspection apparatus. On the contrary, FIG. 11B is a scatter diagram of defect size in a condition that size, which was calculated with performing correction based on feature quantity of a defect (for example, defect size) to a defect defected by the defect inspection apparatus, comparatively corresponds to size measured by SEM. Size may be calculated by obtaining the correction factor for each defect type (convex defect, concave defect, planar defect or the like), rather than the feature quantity of a defect.
[0049] While a procedure of temporarily obtaining size before correction is shown here, size may be calculated at a time during size calculation using information such as feature quantity of a defect or the defect type. For this purpose, information on defects such as feature quantity of a defect or a defect type can be treated as a variable in a size calculation formula in size calculation.
[0050] FIG. 12 shows a relationship between the defect inspection apparatus according to embodiments of the invention and a semiconductor manufacturing process. A wafer after passing through a particular step is inspected by the defect inspection apparatus according to embodiments of the invention. In a manufacturing process 810 , for example, inspection is carried out after a photolithography step ( 810 ). After the inspection, a defect is observed by review apparatus 1001 or 1002 , so that a cause of the defect is estimated from a type, size, or a shape of the defect to find a step where the defect is caused, thereby a manufacturing device in the relevant step is managed. When the cause of the defect is not found only by defect observation, element analysis by an analyzer 1003 or observation of a section profile of the defect is performed for further detailed investigation to search the cause of the defect. As described above, a yield of the semiconductor device is improved by repeating inspection and measures, consequently reliable semiconductor device can be manufactured.
[0051] FIG. 13 shows a relation between the number of defects and a yield of a semiconductor product. A reference 906 indicates transition of the yield of the semiconductor product, a reference 907 indicates transition of total detection number of defects in a particular step. A reference 908 indicates transition of the number of a particular type of defects (in this case, short-circuit defect). While the yield 906 is significantly decreased in a hatched period in FIG. 13 , the total detection number 907 is increased only slightly. When the detected defects are classified, and the number of short-circuit defects is noticed, it is known that the short-circuit defects are increased in the period where the yield is decreased. In addition to the total number of defects, defects are classified, and the number is monitored for each defect type, thereby information in correlation with the yield of the semiconductor product can be obtained. The number of defects of which the size is at least management size may be noticed and managed by using a defect size calculation value rather than the defect type. The management size is determined based on a wiring rule in an inspection step. While not shown, criticality of the defect may be calculated from the defect size, defect type, and wiring rule to monitor the number of defects having at least a certain value of criticality.
[0052] FIGS. 14A to 14B are conceptual diagrams of defect detection thresholds T 01 , T 02 and a feature-quantity extraction threshold T 03 . FIG. 14A shows an example where the defect detection threshold T 01 is equal to the feature-quantity extraction threshold T 03 . In inspection of a semiconductor wafer, the defect detection threshold T 01 is normally set high to suppress false detection of a normal portion. Therefore, in FIG. 14A , only a part of defect signals can be used. Thus, as shown in FIG. 14B , the feature quantity is extracted with a threshold (T 04 ) lower than the defect detection threshold T 02 , thereby more effective extraction of the feature quantity can be performed.
[0053] FIG. 15 shows a display example of a defect detection result. A reference 801 indicates an example of a display screen. In a defect map ( 802 ), display is classified depending on whether defect size is at least a defect management size determined at setting of inspection conditions or not, thereby trouble occurrence and a level of influence on the yield can be instinctively determined. Moreover, defect display is clicked by a mouse, thereby defect ID, size (calculation value of the defect inspection apparatus), a defect type and the like can be shown ( 803 ).
[0054] Moreover, a graph showing frequency of defect occurrence is displayed for each defect size ( 807 ), thereby the trouble occurrence and the level of influence on the yield can be also instinctively determined.
[0055] On the screen, a region 804 for displaying the total number of detected defects or the number of the defects for each size, a region 805 for displaying an operational panel, a region 806 for setting a inspection condition, a region 808 for displaying a defect list are also provided. The display regions may be displayed on one screen at the same time, or may be displayed on separated screens respectively, or several regions of them may be displayed in a combined manner.
[0056] FIG. 16 shows an example of the illumination optical system 102 in the configuration of the defect inspection apparatus shown in FIG. 1 . Here, an example where the light source 101 is a laser light source is shown. Laser 1011 emitted from the laser light source 101 is diverged at a certain divergence angle, and made into parallel light by a lens 1021 , and then shaped to be one-sided condensing illumination by a cylindrical lens 1022 and then irradiated to a wafer surface. An illumination pattern is linear on the wafer surface, and used in a combined manner with scan of the stage, thereby a certain area of the wafer surface can be collectively detected. In this case, for the sensor 304 , a linear sensor corresponding to the illumination area or a TDI sensor (Time Delay Integration Sensor) is preferably used. When the TDI sensor is used for the sensor 304 , a signal detected by the TDI sensor is outputted in parallel from a plurality of taps of the TDI sensor, and the signals outputted in parallel are subjected to signal processing in parallel in the signal processing section 400 , thereby defect detection speed can be improved. When the illumination pattern is a dot-like pattern, AOM, AOD, a galvanometer mirror or the like is used in the illumination optical system to allow scan by the dot-like illumination, and movement of the stage is combined therewith, thereby the whole surface of the wafer can be inspected.
[0057] The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiment is therefore 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 therefore intended to be embraced therein. | When size of a defect on an increasingly miniaturized pattern is obtained by defect inspection apparatus in the related art, a value is inconveniently given, which is different from a measured value of the same defect by SEM. Thus, a dimension value of a defect detected by defect inspection apparatus needs to be accurately calculated to be approximated to a value measured by SEM. To this end, size of the defect detected by the defect inspection apparatus is corrected depending on feature quantity or type of the defect, thereby defect size can be accurately calculated. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The field of the invention relates to data processing and in particular to storage of data in memory arrays.
[0003] 2. Description of the Prior Art
[0004] In the field of data storage microelectronic storage devices such as memories are being designed to store increasing amounts of data in ever smaller devices. This has led to faults within the devices becoming more common. Memories such as SRAM memories are therefore now being designed with some redundancy. This redundancy may be in the form of additional redundant rows and/or columns in each array. During testing of the array, errors can be detected and the redundant rows and/or columns can be used to replace the rows and/or columns having the errors within them. This means that the memories are repairable and provides a way of dealing with the increasing number of errors in such devices.
[0005] As each storage element within such an array is located within both a column and a row, the repair of a faulty element can be done using either a redundant row or column. Depending on the arrangement of other faulty locations in the memory it may be more efficient to repair an error with either a redundant row or a column. In order to correct the most number of errors present using the redundant rows and columns that are available various schemes for analysing the array have been devised. In one scheme a map of the whole array is made and a covering algorithm is then generated to arrange the redundant rows and columns to cover the maximum number of errors possible. This provides the best solution but is expensive in area to perform.
[0006] A simpler scheme for determining the best way of using the available redundant row and columns to cover the highest number of errors is described in “A Built-In Self-Repair Analyzer (CRESTA) for Embedded DRAMs” by Kawagoe et al, ITC International Test Conference 2000 pages 567-574. In this paper an array having two redundant rows and two redundant columns is considered, and the best repair solution is found deterministically by trying the spare rows and columns in different orders in real time RRCC, RCRC, RCCR, CRRC, CRCR, CCRR and finding the solution which covers most or all of the errors. This solution is then used to repair the memory.
[0007] A drawback of the “CRESTA” scheme is that the area required to provide the logic to implement the scheme is still considerable. Furthermore, with two redundant rows and columns the number of potential solutions is only six, however with an increasing number of redundant rows and columns this will increase dramatically. An increase in the potential number of solutions will make the “CRESTA” scheme more and more expensive in area.
SUMMARY OF THE INVENTION
[0008] A first aspect of the present invention provides a memory array comprising a plurality of rows and a plurality of columns, each row comprising at least one addressable word, said memory array comprising at least one redundant row and at least one redundant column; error detection circuitry for analysing said memory array, by addressing words within said memory array and detecting errors within said addressed words; error repair circuitry for selecting for a detected error either a redundant row or a redundant column to replace one of said row or column containing said error; wherein said error repair circuitry is configured to determine for said detected error whether said error is a single error bit in said addressed word or whether it is one of a plurality of error bits within said word, and if said error is said one of said plurality of errors, said error repair circuitry is configured to preferentially select a redundant row rather than a redundant column to repair said error.
[0009] The present invention recognizes that a simple analysis of the word being addressed may provide a very good indication as to whether a row or column would be the preferred repair option for that error. Two errors within the word would indicate that a row would be a good option as it would repair both errors using a single redundant resource, while if there is only one error then this may not be the preferred solution. The present invention uses the fact that as the conventional access scheme to a memory involves addressing a word that lies in a row, then it is a simple matter to analyse that word to discover if it has one or multiple errors in it. If multiple errors are discovered then repairing these errors with a row replacement will result in all of the multiple errors within that word being repaired by this single replacement. Thus, this simple analysis can provide, in some cases, a dramatic improvement in allocation of repair resource and leads to a repair solution that is inexpensive in area but still very successful. It is not necessarily the best solution but it is a good solution that can be provided with few additional resources.
[0010] In some embodiments each row comprises a plurality of addressable words; and said error repair circuitry is adapted to group together at least some addressed words from a same row and to determine for an error detected within said same row whether said error comprises a single error within said grouped words or whether it comprises one of a plurality of errors within said grouped words, said error repair circuitry being configured to preferentially select a redundant row rather than a redundant column to repair said error if said error is one of said plurality of errors, and if said error is said single error said error repair circuitry is configured to preferentially select a redundant column to repair said error.
[0011] The simplest case is to analyse an addressed word, however, the scheme can be improved further, without much additional logic by analysing several of the words in a row. As rows are repaired as a complete entity by replacing them with a redundant row then clearly it is advantageous when determining the preferable repair scheme to analyse more than one of the words in a row to determine if the error is a single error or one of multiple errors in that row. If it is a single error then the preferred repair scheme may be to use a redundant column while if there are multiple errors a redundant row is preferable.
[0012] In some embodiments said error repair circuitry is configured to group together all words from a same row.
[0013] Analysing all the words in the row provides a good scheme for discovering multiple errors in a single row and this information can be used to decide if a redundant row is the preferred repair mechanism.
[0014] In some embodiments, in response to detecting that said detected error is a single error bit in said addressed word, said error repair circuitry is configured to preferentially select a redundant column rather than a redundant row to repair said error.
[0015] Generally if the error is a single error then the preferred solution is a redundant column rather than a row. The analysis of rows to find if there are multiple errors within them is straightforward given the way that memories are addressed, thus, it is this that is analysed and thus, if there is only a single error in the row a column can be used to repair it, which leaves the redundant rows to be used to repair multiple errors where possible. Clearly if there are no spare redundant columns then a redundant row could be used.
[0016] In some embodiments, said error repair circuitry is responsive to detecting no available redundant row or column corresponding to said preferential selection, to select an alternative available redundant column or row instead of said preferential selection to repair said error, and in response to detecting no available redundant rows or columns to issue a repair failed signal.
[0017] Where no redundant row or column is detected then the fault cannot be repaired and a repair fail signal is issued.
[0018] In some embodiments, said error detection circuitry is configured to analyse said memory by addressing said words within said memory array in at least one predetermined order.
[0019] The location of the errors can be detected by addressing the words in the memory array in one or more predetermined orders. The order of addressing can be selected so that the location of the errors are found efficiently. The order used will depend upon how data words are stored in the array and thus, will vary between embodiments.
[0020] Although the memory array may only have one redundant row and column, in some embodiments said memory array comprises a plurality of redundant rows and columns.
[0021] A further aspect of the present invention provides a method of repairing a memory array comprising at least one redundant row and at least one redundant column comprising the steps of: analysing said memory array, by addressing words within said memory array and detecting errors within said addressed words; selecting for a detected error either a redundant row or a redundant column to replace one of said row or column containing said error; wherein said step of selecting a redundant row or column comprises determining for said detected error whether said error is a single error in said addressed word or whether it is one of a plurality of errors within said word, and if said error is said one of said plurality of errors preferentially selecting a redundant row rather than a redundant column to repair said error.
[0022] A yet further aspect of the present invention provides a means for storing data comprising a plurality of rows and a plurality of columns, each row comprising at least one addressable word, said means for storing data comprising at least one redundant row and at least one redundant column; error detecting means for analysing said memory array, by addressing words within said memory array and detecting errors within said addressed words; error repairing means for selecting for a detected error either a redundant row or a redundant column to replace one of said row or column containing said error; wherein said error repairing means is configured to determine for said detected error whether said error is a single error bit in said addressed word or whether it is one of a plurality of error bits within said word, and if said error is said one of said plurality of errors, said error repair means is configured to preferentially select a redundant row rather than a redundant column to repair said error.
[0023] The above, and other objects, features and advantages of this invention will be apparent from the following detailed description of illustrative embodiments which is to be read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] FIG. 1 a shows a memory to be repaired according to an embodiment of the present invention;
[0025] FIG. 1 b shows a memory and associated test and repair circuitry according to an embodiment of the present invention;
[0026] FIG. 2 a shows memory repair circuitry according to an embodiment of the present invention;
[0027] FIG. 2 b shows a flow diagram illustrating steps in a method for repairing a memory using the repair circuitry of FIG. 2 a;
[0028] FIG. 3 shows steps performed in repairing a memory according to an embodiment of the present invention;
[0029] FIG. 4 a shows a two bank memory to be repaired according to an embodiment of the present invention;
[0030] FIG. 4 b shows a flow diagram illustrating steps in a method for repairing the memory of FIG. 4 a;
[0031] FIG. 5 shows a flow diagram illustrating steps in a method for repairing a memory where the redundant rows may themselves be faulty;
[0032] FIG. 6 a shows a two bank memory with two sections to be repaired according to an embodiment of the present invention; and
[0033] FIG. 6 b shows a flow diagram illustrating steps in a method for repairing the memory of FIG. 6 a.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0034] FIG. 1 a schematically shows a repairable memory array 10 having redundant columns C 1 and C 2 and redundant rows R 1 and R 2 . The memory array comprises a plurality of rows and columns, a data element lying within a particular column and row. The data elements are in this embodiment addressed as words, a word lying in a row across several columns.
[0035] FIG. 1 b shows the memory array 10 and associated test and repair circuitry. There is test circuitry 15 that is associated with the array that tests the array by writing predetermined patterns of data to the memory array and reading them out and comparing them with expected values. The way that data is stored in the array determines the data patterns required to completely test the array.
[0036] There is also error repair circuitry 50 that is associated with the array and that in response to detecting errors from the test data, such as those shown in row 12 , or row 14 of FIG. 1 a, determines if they are a single error such as is the case for row 14 or one of multiple errors in the addressed word as is the case for row 12 . In the case of multiple errors, the row, in this case row 12 is replaced with a redundant row R 1 , so that addressing of row 12 when the memory is in use will result in row R 1 being accessed. In the case of a single error as in row 14 , the column that this error lies in, in this case column 16 , is replaced by redundant column C 1 in future addressing of the memory.
[0037] FIG. 2 a shows the error repair circuitry 50 for performing repair of memory 10 of FIG. 1 in more detail. Memory 10 is tested using a built in self test function and the output from this testing procedure is compared with the expected output from a memory without errors. An exclusive OR of the two signals is then made to generate an error bus signal error [n−1:0] that is input to this repair circuit 50 . This signal is input to AND gate 52 where it is ANDed with an error mask which is data that is generated from already repaired memory locations. If the new error does not correspond to any previously repaired locations then the error is captured in the error accumulation register 60 .
[0038] Analysis of how the repair can be performed is then made. First it is determined whether all redundant rows and columns have already been used. If they have then an irrepair flag is generated indicating that no further repairs can be made. If all the redundancies have not been used then an analysis is performed to determine how many bits have failed within this addressed word and where they are located. The position of the failed bits are then stored. If there is one faulty bit then the redundant columns are checked to see if one is available. If a redundant column is available the column location of the error is checked and a repair position is determined and entered into a pair of registers 80 , 84 or 82 , 86 . That is, if C 1 is the column that is to repair the error then the column address to be repaired is input into register 82 and the bit position of the error is input into register 86 . Similarly if C 2 is the redundant column to be used then the column address is input into register 80 and the bit position into register 84 .
[0039] If there is more than one failed bit or if no redundant column is available then a check is made to see if any redundant rows are available. If a redundant row is available then the row to be repaired is inserted into the repair row registers 70 or 72 corresponding to this redundant row. This faulty row is thereby replaced with the available redundant row.
[0040] The logic analysing the error data and the availability of redundant rows and columns is logic 90 . Control signals to the repair circuitry are received and output via input/output circuit 95 .
[0041] FIG. 2 b shows a flow diagram illustrating schematically the steps performed during the repair of an error by the circuit of FIG. 2 a. In response to detecting an error the AMRA logic 90 is enabled and this determines if the error count is 2 or more. If it is not then it is determined if redundant column C 1 is available. There is a flag associated with the column that is set to 1 to indicate it is not available. Thus, if C 1 =0 this column is used to repair the error by replacing the faulty column with C 1 , the flag associated with C 1 is then set to 1. If redundant column C 1 is not available the flag associated with C 2 is checked. If it is available then C 2 is used to repair the faulty column and the flag C 2 is set to 1, if not then the redundant rows are considered.
[0042] If the error count is 2 or more or if there are no available columns then the redundant rows are considered. First the flag associated with R 1 is looked at. If it is 0 then R 1 is used to replace the faulty row, the flag associated with R 1 is set to 1 and the address of the row to be repaired is input to the row repair register for R 1 . If R 1 is already used then R 2 is checked and a similar process performed. If no redundant rows are available then an irrepair flag is generated that tells the testing circuit that it cannot repair the memory.
[0043] FIG. 3 shows a flow diagram illustrating steps performed to repair errors during testing of a memory. These steps are performed during testing of a memory when an error has been found and it has been determined that the error in the memory may be repairable. Initially a check is made to see if all the redundant rows and columns for the memory have already been used. If they have then the error that has been detected is not repairable and an error is generated. If they have not all been used then memory testing is paused and the number of failed bits for an address is counted and the failed bit position is stored. It is then determined whether two or more bits have failed. It should be noted that although in this embodiment the number of failed bits for an addressed word is counted, in other embodiments the number of failed bits in the whole row being addressed may be counted and the method performed in the same way. In that case the decision to preferentially use redundant rows or columns is made in dependence on the number of errors in the whole row rather than the number in the addressed word.
[0044] If only one error has been detected then it is determined if all column redundancies have been used. If they have then the method looks at row redundancies as is set out below. If they have not all been used then the column repair value is captured in the respective column repair register and this redundant column is used to repair the error. The memory testing can then be resumed.
[0045] If there are two or more errors or if there is only one but all redundant columns have been used then a check is made to see if all the row redundancies have been used. If they have not been used then the row repair value in the respective row repair register is captured and this redundant row is used to repair the faulty row. Memory testing is then resumed. If all row redundancies have been used then an indication is given that the memory cannot be repaired and an error is generated.
[0046] FIG. 4 a shows a memory 10 having two banks, a bank 11 for the lower half bits LHB and a bank 13 for the upper half bits UHB. Each bank has a redundant column, C 1 or C 2 and four redundant rows R 1 to R 4 .
[0047] FIG. 4 b shows a flow diagram of a method for repairing a memory such as that illustrated in FIG. 4 a. In this embodiment, the memory being repaired is a two bank memory with the lower bits being in the left hand bank and the upper bits being in the right hand bank. In this arrangement, there are 4 redundant rows, in larger memories more redundant rows may be provided.
[0048] In this embodiment, the number of errors are counted for each bank thus, if there is more than one error in either bank 11 or 13 then row redundancy is given priority. If there is only one in either bank 11 or 13 then column redundancy is given higher priority. This is shown in FIG. 4 b.
[0049] In FIG. 4 b an error is detected and then it is determined if there are two or more errors in either the upper half or the lower half bits. If there are, then the redundant rows R 1 -R 4 are analysed to see if any are available and if not then an irrepair signal is generated. If one of them is available then the address of the faulty row is written into the corresponding repair register and the flag associated with the redundant row is set to 1 to show that it is no longer available for repair.
[0050] If there are less than two errors in a single half i.e. one in either or both of the upper half or the lower half then it is determined first of all if it is the upper half or the lower half that requires correction. If it is the upper half then C 2 is used for the repair provided it is available and if it is the lower half then C 1 is provided for repair provided it is available. If there is an error in both then they are both used for repair provided they are both still available. If any of the required redundant columns are not available for repair then the row redundancies are looked at to see if a redundant row can be used to repair the error.
[0051] FIG. 5 shows a similar embodiment which additionally shows what occurs if following replacement of a faulty row with a redundant row, the memory test procedure detects an error in the redundant replacement row. In such a case the repair register for the faulty redundant row is set to indicate irrepair, and the address of the row to be replaced is then input to a further available redundant row. Thus, if a faulty row was replaced by redundant row R 1 and this was later seen to be faulty, it would be marked as such using an irrepair value stored in the repair register for R 1 , and the location of the original faulty row would be input to the repair register for R 2 , such that row R 2 would replace this row.
[0052] FIG. 6 a shows a memory 10 divided into two banks 15 and 17 for storing lower half and upper half bits respectively. The two banks are each themselves divided into two sections or banks at lines 15 a and 17 a respectively, one half having redundant rows R 1 to R 4 and the other half having redundant rows R 5 to R 8 .
[0053] FIG. 6 b shows a flow diagram of a method for repairing the memory of FIG. 6 a. This is very similar to the flow diagram of FIG. 4 b, only in this case when a row repair is to be done, it is first determined if it is a row in the top half of the bank or the lower half Depending where it is located either one of rows R 1 to R 4 or one of rows R 5 to R 8 are used if available. This dividing of the memory into different portions or banks is done where the memory is large and although in this embodiment it is shown as being divided into two portions or banks, it should be clear that it could be divided into more portions.
[0054] Although illustrative embodiments of the invention have been described in detail herein with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments, and that various changes and modifications can be effected therein by one skilled in the art without departing from the scope and spirit of the invention as defined by the appended claims. | A memory array comprising a plurality of rows and a plurality of columns, each row comprising at least one addressable word, said memory array comprising at least one redundant row and at least one redundant column; error detection circuitry for analysing said memory array, by addressing words within said memory array and detecting errors within said addressed words; error repair circuitry for selecting for a detected error either a redundant row or a redundant column to replace one of said row or column containing said error; wherein said error repair circuitry is configured to determine for said detected error whether said error is a single error bit in said addressed word or whether it is one of a plurality of error bits within said word, and if said error is said one of said plurality of errors, said error repair circuitry is configured to preferentially select a redundant row rather than a redundant column to repair said error. | 6 |
This application is a continuation application of U.S. patent application Ser. No. 12/452,466, filed May 20, 2010, which is a national stage of PCT/N2008/000158 filed Jul. 3, 2008, and published in English, which has a priority of New Zealand No. 556329 filed Jul. 3, 2007, and New Zealand No. 565118 filed Jan. 15, 2008, hereby incorporated by reference.
FIELD OF THE INVENTION
The present invention relates to a panel mount for mounting a panel such as a glass pane.
BACKGROUND
Glass panes are used in buildings for many purposes. Glass panes can offer partitions within offices, showers, as a guard rail around an edge with a drop off, as fencing for a pool and the like.
Such glass panes are normally of a reinforced glass that has substantial impact or break resistance. Post production workability of such glass can be difficult.
Mounting of such glass panes can be cumbersome. The glass panes are heavy. They are inflexible. They can be difficult and time consuming to drill.
Means for mounting glass panes are known. By way of example U.S. Pat. No. 6,434,905, U.S. Pat. No. 4,837,993 illustrate ways in which a glass pane may be mounted. However these means for mounting do not readily lend themselves to the mounting of glass panes that may not necessarily align with the slot that is provided for receiving the glass pane. Alignment of the slot with the glass pane and/or vice versa can be a time consuming exercise. Particularly where for example such glass panes are mounted from a fixed structure of a building to which the brackets themselves need to be secured. The brackets themselves, secured to a fixed structure may not present the slot in the desired orientation to receive and hold the glass pane in its desired position.
WO03/091516 illustrates a device for supporting a glass pane. Such a device may be used in combination with other like devices that are for example mounted in concrete or to concrete to support the glass pane along its edge. Where multiple devices are used, alignment of each device with the glass pane as well as with each other becomes important. Use of the invention of WO03/091516 requires the glass to be drilled. This means that both slot alignment between multiple devices and spacing between devices is necessary to secure a glass pane.
Accordingly it is an object of present invention to provide a panel mount to provide improvements to known means for mounting a panel and/or that has the capacity to accommodate with slight misalignment relative to the desired position of glass to be held and/or that will at least provide the public with a useful choice.
BRIEF DESCRIPTION OF THE INVENTION
In a first aspect the present invention consists in a panel mount for non penetrative fastening of a panel (such as a glass pane), said panel mount comprising:
clamp jaws defining an elongate slot in which an edge of a panel can be received,
a foot for mounting and fastening said clamp jaws to a structure,
at least one of said clamp jaws holding at least two spaced apart threaded fasteners that can be actuated by a user,
at least one clamp member located intermediate of said threaded fasteners and one side of said panel (when received in said slot),
at least one base member of a configuration to be contiguous an edge of the panel when located in said slot, to operatively act as a partial extension of the panel and positioned such that at least one of said threaded fasteners can act thereon (directly or indirectly),
the threaded fasteners, in cooperation with the clamp jaws, capable of operatively clamping said panel to hold it in said slot.
Preferably the base member is of the same width (being in a direction in which the same as force of clamping acts) as the thickness of the panel.
Preferably the foot and the clamp jaws are integrally formed.
Preferably the foot is engaged to the clamping jaws.
In a second aspect the present invention consists in a panel mount for non penetrative fastening of a panel (such as a glass pane), said panel mount comprising.
a housing that includes a slot to receive the edge of a panel, the housing defining a cavity that include at least one opening on at least one side of the slot and at the base of the slot,
a base member positioned in a location to act as an extension of and to be contiguous with the panel at an edge of the panel within said cavity,
an elongate clamp member located in said cavity in a manner to allow it to move in a direction normal to the panel and, via said at least one opening, can effect a clamping force onto the panel in conjunction with resistance to movement of the panel offered by the housing from the other side of the slot,
the clamping force being effected by at least two fasteners carried by the housing, a first fastener that acts to apply a force in a direction normal to the panel onto the elongate clamp member and a second fastener that acts to apply a force in a direction normal to the panel and onto the base member.
Preferably there are two clamp members that each extend on a separate side of the panel (when located in the slot) and that each extend on a separate side of the base member.
Preferably there are two pairs of fasteners each having one fastener on each side of the panel and each fastener of a said pair located to act in opposite directions.
Preferably the panel is retained between the two clamp members upon a tightening of the fasteners.
Preferably a first of the pair of fasteners is located to apply a force acting through the base member.
Preferably a second of the pair of fasteners is located to apply a force acting through the panel and adjacent the edge of the panel when located in the slot.
Preferably a second of the pair of fasteners is located to apply a force onto said clamp members and acting through and normal to the panel and adjacent the edge of the panel when located in the slot.
Preferably a third pair of fasteners is provided that is located to act on the clamp members at a location proximate to the mouth of the slot.
Preferably the cavity includes an opening at the base of the housing to allow the at least one clamp member and base member to be inserted in to the housing.
Preferably said at least one opening of the cavity is an elongate slot.
Preferably said at least one opening of the cavity is at least one hole.
Preferably there is one of said at least one openings for each of the clamping members.
Preferably the base member is substantially of the same thickness as the panel.
Preferably a packer is located between each clamp member and the panel.
Preferably the packer is also located between each clamp member and the base member.
Preferably the fasteners are threaded fasteners.
Preferably the housing includes apertures to receive the fasteners the apertures including an opening to the cavity to allow the fasteners to act (directly or indirectly) onto a respective the clamp member and said base member.
Preferably the slot is a U-shaped slot.
In a further aspect the present invention consists in a panel mount for non penetrative fastening of a panel (such as a glass pane), said panel mount comprising.
a housing that includes a slot to receive the edge of a panel, the housing also including at least one cavity defining an elongate opening to and on each side of the slot,
for each side of the panel, an elongate clamp member located at least in part within said cavity in a manner to allow it to operatively move in a direction parallel to the normal to the panel to effect a clamping force in conjunction with resistance to movement of the panel offered from the other side of the slot by the other elongate clamp member onto the panel
a base member located between the two clamp members and adjacent an edge of the panel and of a configuration to allow the clamp members to also effect a clamping force onto the base member,
the clamping force being effected by at least two pairs of fasteners carried by the housing, each fastener of a pair to apply a clamping force in opposite directions, the first of a pair of fasteners acting to apply a clamping force passing through the base member and a second of a pair of fasteners to apply a clamping force passing through the panel adjacent an edge of the panel when located within the slot.
In still a further aspect the present invention consists in a panel mount for non penetrative fastening of a panel (such as a glass pane), said panel mount comprising:
clamp jaws defining an elongate slot in which an edge of a panel can be received, a foot for mounting and fastening said clamp jaws to a structure, at least one of said clamp jaws carrying at least one threaded fastener that can be actuated by a user, including when said foot is fastened to said structure, the threaded fastener(s) of said at least one clamp jaw, in cooperation with the other clamping jaw, capable of operatively clamping said panel to hold it in said slot, irrespective of any non-parallel disposition of the plane of said panel to the elongate direction of said slot.
Preferably each clamp jaw carries at least one threaded fastener that can be actuated by a user, including when said foot is fastened to said structure, the threaded fastener(s) of each clamping jaw, in cooperation with the or each other threaded fastener, capable of operatively clamping said panel to hold it in said slot, irrespective of any non-parallel disposition of the plane of said panel to the elongate direction of said slot.
Preferably said foot includes a means to fasten, to fasten to or with said structure.
Preferably there is at least one pair of clamp jaws.
Preferably each clamp jaw defines an elongate rectilinear slot.
Preferably a mouth opening is defined by the distal ends of each slot and through which part of said panel can enter said slot.
Preferably said clamp jaws are, at their proximal end, engaged to said foot.
Preferably said foot is a foot plate positioned so that the elongate slot extends in a direction normal to the plane of said foot plate.
Preferably said threaded fasteners are engaged to said clamp jaws to move in a direction lateral to the elongate direction of said slot (and preferably normal to the plane of the panel).
Preferably said threaded fasteners can extend into said slot.
Preferably an intermediate member is located between a or all said threaded fasteners and, when in situ, said panel.
Preferably said intermediate member is a protective member that prevents direct contact of said threaded fasteners with said panel.
Preferably said intermediate member is a planar member or elongate member that extends parallel to the elongate direction of the slot.
Preferably a said intermediate member is located at each side of said slot, each intermediate member to be reacted on by a or the threaded fasteners held by one of the clamp jaws.
Preferably each said intermediate member extends from said distal end of each said clamp jaw to or towards the opposite end of said slot.
Preferably each said threaded fastener is located in a threaded hole passing through a respective clamp jaw.
Preferably the slot defined by said clamp jaws terminates short of the foot at a slot base.
Preferably said base is able to engage with an edge of said panel.
Preferably said threaded fasteners can be actuated by a user when the panel mount is fastened to the fixed structure.
Preferably the panel mount is one that is used as part of a glass pane incorporating balustrade system.
Preferably the panel mount is one that is used as part of a glass pane defined wall.
Preferably said slots are open sided.
In a further aspect the present invention consists in a method of mounting a panel (such as a glass pane) relative a fixed structure, comprising:
securing, in a spaced apart configuration to a fixed structure, at least two panel mounts as claimed in any one of the preceding claims in a condition wherein their slots are substantially in alignment,
inserting a panel into the slot of each panel mount,
holding the panel in the desired position,
adjusting the threaded fasteners to clamp said panel in place in said desired position.
In a further aspect the present invention consists in a panel defined wall, partition or fence or panel including balustrade system wherein a panel is edge supported by at least one panel mount as herein before described.
In still a further aspect the present invention consists in a panel mount as herein described with reference to any one of the drawings.
Preferably the means to fasten is an aperture passing through said foot to allow a fastener to pass there through and secure said panel mount to said structure.
Preferably the means to fasten is a fastener that projects in a direction away from said elongate body to pass into an aperture of said structure and secure said panel mount to said structure.
Preferably the structure is a floor, beam, bearer or pad.
To those skilled in the art to which the invention relates, many changes in construction and widely differing embodiments and applications of the invention will suggest themselves without departing from the scope of the invention as defined in the appended claims. The disclosures and the descriptions herein are purely illustrative and are not intended to be in any sense limiting.
This invention may also be said broadly to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, and any or all combinations of any two or more of said parts, elements and features, and where specific integers are mentioned herein which have known equivalents in the art to which this invention relates, such known equivalents are deemed to be incorporated herein as if individually set forth.
As used herein the term “and/or” means “and” or “or”, or both.
As used herein “(s)” following a noun means the plural and/or singular forms of the noun.
The term “comprising” as used in this specification means “consisting at least in part of”. When interpreting statements in this specification which include that term, the features, prefaced by that term in each statement, all need to be present but other features can also be present. Related terms such as “comprise” and “comprised” are to be interpreted in the same manner.
BRIEF DESCRIPTION OF THE DRAWINGS
A preferred form of the present invention will now be described with reference to the figures in which:
FIG. 1 illustrates a panel mount,
FIG. 2 illustrates a front view of the panel mount that also includes the shroud,
FIG. 3 is a front view of the clamping jaws,
FIG. 4 is a front view of the shroud,
FIG. 5 is a plan view of the foot,
FIG. 6 is a front view of the packing,
FIG. 7 is a side view of FIG. 4 ,
FIG. 8 is a front view of part of a panel mount illustrating a panel in situe,
FIG. 9 is a front view of a pane supported by a plurality of panel mounts,
FIG. 10 shows a variation of the foot shape of the mount,
FIG. 11 shows a cross-sectional view of the panel mount with the housing and the clamping members,
FIG. 12 shows a front view of the panel mount illustrating the movement of the clamping members into the opening of the housing,
FIG. 13 illustrates the panel mount of the present invention,
FIG. 14 illustrates the clamping members and the base members,
FIG. 15 shows the front view of the panel mount together with the bracket,
FIG. 16 illustrates the bracket mounted on a fixed structure and FIGS. 17 a - d show other variations.
DETAILED DESCRIPTION OF THE INVENTION
With reference to FIG. 1 there is shown a first version of a panel mount 1 . It is shown partially exploded, and absent of a shroud that may be used. With reference to FIG. 2 the preferred shroud 2 is shown.
With reference to FIG. 1 , the panel mount 1 includes clamping jaws 3 , 4 . The clamping jaws define a slot 6 therebetween. The slot 6 is an elongate slot that in the preferred mode of use extends vertically. The slot, at the distal ends 8 , 9 of the clamp jaws 3 , 4 presents a mouth opening 10 into and through which an edge of a glass pane can be received.
Whilst in this form the panel mount as herein described is designed for use with a glass pane, it will be appreciated by a person skilled in the art that other forms of building panels may be used in combination with panel mounts of the present invention. The present invention lends itself particularly suitable for use with a glass pane since the invention does not require for holes to be drilled through the glass pane for the purposes of mounting of the glass pane by the panel mount.
The slot receives the glass pane by passing the pane through the mouth 10 . However the slot also includes side openings to allow sliding location of the glass pane therethrough. The slot from its mouth 10 to its base 11 is preferably of a length that stops short from the foot 12 .
The foot 12 can mount the panel mount to a fixed structure. The clamp jaws 3 , 4 are preferably directly engaged and supported by the foot 12 . The panel mount may be made as a unitary member or alternatively may be fabricated from several members. Where it is fabricated, the jaws 3 , 4 may for example be welded to the foot 12 .
The clamp jaws 3 , 4 are preferably of a unitary body as for example shown with reference to FIG. 3 . The unitary body 13 includes a base portion at where the clamp jaws 3 , 4 are affixed to or from which the foot 12 extends. As can be seen the base 11 of the slot does not extend to the proximal end 14 at where the foot 12 is fixed. The distance D defines the separation of the bottom edge of a glass pane, to the floor where for example the foot 12 is to be mounted.
The foot 12 includes means 16 , for fastening the foot to a fixed structure of a building. The means 16 in the preferred form are apertures through which a penetrative fastener can extend for securing the foot to the fixed structure. Such penetrative fasteners may be screws, dyna bolts, or other, selected for suitable use with the materials of the fixed structure to which the panel mount is to be mounted.
Alternative means to fasten the foot 12 to the fixed structure may be provided. The foot 12 may include rods to be cast into a suitable material such as concrete or resin. The foot may be a stud or footing as shown in FIG. 10 to be set into concrete or resin.
One and preferably each of the clamp jaws 3 , 4 includes at least one aperture 20 to receive a threaded fastener 21 . As can be seen in FIG. 1 , each clamp jaw includes 2 apertures to each receive a threaded fastener. In the preferred form apertures are provided for each clamp jaw 3 , 4 . The threaded fasteners may be otherwise disposed to, or from the jaws.
Each threaded fastener can be actuated by a user by for example using a tool such as a screw driver or allen key. In the most preferred form the threaded fasteners are grub screws. The fasteners may extend into the slot to operatively engage with a pane that is received in the slot. Alternatively the threaded fasteners may actuate an intermediate member that engages directly against the pane. However it may be that the threaded fasteners may make direct contact with the pane, or each may have a shoe to contact the panel.
In FIG. 1 , intermediate members 30 are shown. The intermediate members 30 are for example packers or spacers that are positioned intermediate of a pane in the slot and each of the threaded fasteners. They may be strips of a material such as a metal or plastic that is provided at each of the sides of the slot as shown in FIG. 1 . They may be flexible so as to deflect when the threaded fasteners are moved to engage thereon. The packers may be of a material (or include a material) that has a high coefficient of friction with the material of the panel.
With reference to FIG. 8 , there is illustrated part of the panel mount of the present invention. The width “W” of the slot is greater than the thickness “T” of the pane 33 . The width “W” is sufficient to allow for at least some misalignment of the pane 33 to occur with the elongated direction of the slot 6 . When affixed to a fixed structure the slot may not be presented in a position that perfectly aligns with the position that the pane 33 is desired to be in. Misalignment can be accommodated by the slot 6 due to the size of the slot being larger than the thickness of the pane. With the use of the threaded fasteners the pane, despite not being perfectly aligned within the slot, can still be clamped through the cooperation of the threaded fasteners with each other.
In use, the panel mount is firstly mounted to a fixed structure in a position that is, as best as possible, provided to present the slot in alignment with the desired position of the pane 33 . A pane is then inserted into the slot 6 and held in its desired position. A person can then actuate the threaded fasteners 21 so as to clamp the pane 33 and hold it in the slot.
Once the pane is secured, a shroud 2 may be positioned over the clamp jaws 3 , 4 so as to obscure these from sight. The shroud 2 preferably also includes a slot that may be of a size smaller than the slot 6 . The slot of the shroud 2 may be of a width “W-2” that is smaller than the width “W” of the slot 6 . The slot of the shroud may be of a flexible nature so that it can be at least to some extent compliant to a misaligned positioning of the panel 33 in the slot 6 . The shroud 2 may also cover the foot or part of the foot 12 .
The shroud may include apertures therethrough to allow for a tool to reach the threaded fasteners that are carried by the clamp jaws 3 , 4 . The shroud may be permanently affixed to the clamping jaws and/or the foot. The construction can improve the strength of the mount.
Alternatively the shroud may not include such apertures.
With reference to FIG. 9 there is shown a pane 33 supported by 3 panel mounts relative to a fixed structure 36 .
The mount can more conveniently receive and secure panels and can also allow for subsequent adjustment to occur without needing to remove the mount from the structure. It also does not require the panel to be machined, such as by drilling, to become secured.
FIGS. 11-14 show another form of a panel mount. The panel mount comprises a housing 50 which is or can be affixed to a fixed structure such as a deck in similar(s) as described above.
The housing 50 is preferably of a unitary construction and includes a slot 71 between two clamp jaws 100 and 101 , to receive a pane 33 . When a pane 33 is inserted into the slot 71 , the edge of the pane may rest on the base of the slot 70 . As shown in FIG. 11 , the slot may not extend to the base end of the housing. The housing 50 includes a cavity 65 extending from the underside of the housing 50 to or towards the top of the housing 50 . The cavity is of a shape to receive intermediate members 30 . The housing is preferably made of stainless steel. Alternatively, other metals with similar mechanical properties may be used.
The intermediate members preferably comprise two side clamp members 60 , 61 and a base member 62 in between the side clamp members 60 , 61 . The height of the base member 62 may be smaller than the clamp members 60 , 61 . When inserted in the cavity 65 of the housing, it may be contiguous the underside of the base of the slot 70 of the housing. The thickness of the base member “X” is preferably equal to the thickness of the pane “T”. This is to ensure that the side clamp members 60 , 61 will provide an even distribution of clamping force on the pane 33 prior to being set. The side clamp members can move laterally relative the pane 33 within the cavity 65 .
The width “W” of the slot of the housing is preferably greater than the thickness “X” of the base member to accommodate panes of various thickness.
The side clamp members 60 , 61 are preferably equal in size and dimensions, although different dimensions may be used. The side clamp members 60 , 61 should preferably fit the cavity 65 with a sufficient allowance that enables the side clamp members 60 , 61 to move laterally in the direction towards and away from the pane 33 .
Since the side clamping members are separate members, this allows panes of various nominal thickness (but limited by the width “W” of the slot) to be accommodated by simply varying (for example by substitution) the thickness “X” of the base member without changing the dimensions of the side clamp members to, 61 .
The side clamp members 60 , 61 , and base member 62 are instrumental in providing the clamping forces on the pane.
The two side clamp members 60 , 61 , and base member 62 are preferably made of stainless steel. Alternatively, other types of metal for example aluminium or other materials providing a similar amount of strength may be used. They are substantially rigid.
The housing 50 includes apertures to receive threaded fasteners. Each of the apertures is threaded to receive a threaded fastener. The apertures extend substantially through the side walls (e.g. the clamp jaws 100 and 101 ) of the housing to the cavity of the housing. In the most preferred embodiment, the housing includes three pairs of apertures, each pair of aperture on the opposite sides of the housing. In the most preferred embodiment, one pair of apertures located to allow fasteners to act at the base member 62 , one pair just above and acting on the side clamp members 60 , 61 , and preferably one pair at or towards the upper end of the housing also acting on the side clamp member 60 , 61 . Each pair of apertures are preferably aligned to evenly distribute the clamping force provided by the threaded fasteners on the intermediate members. More than 3 pairs of apertures may be used to provide more rigidity.
The threaded fasteners are actuated by a user for example using a tool such as a screwdriver or allen key and provide the clamping force required to clamp the panel. The threaded fasteners are preferably grub screws, but other fastening devices may alternatively be employed.
As shown in FIG. 11 , packers 30 , are preferably interposed between the intermediate members 60 , 61 , 62 and the panel. The packers may be inserted between the opposite sides of the base member 62 adjacent to the side clamp members 60 , 61 . The packer 30 serves to adequately grip the panel 33 and provides protection for the hard or abrasive side clamp members. Preferably, packers may be made of cork-rubber composite, neoprene, synthetic based rubber of polypropylene. They may be made of material which has a high coefficient of friction with the material of the panel to adequately grip the panel. They are preferably elastic to accommodate any warping and uneven surfaces of the panel. Alternatively, no packer may be interposed.
The mechanics of clamping of the panel will now be explained. As shown in FIG. 11 , the slot of the housing 50 receives the panel by passing the pane through the mouth of the slot 71 to eventually rest on the upper side of the base of the slot 70 of the housing (or on the base member 62 ). The side clamp members 60 , 61 , and base member 62 , preferably inserted into the cavity 65 from the underside of the housing can be manually put and/or kept in place. The side clamp members 60 , 61 may abut against the top end of the cavity wall and the base member 62 may abut the underside of the base of the slot 70 of the housing.
Clamping forces on the panel are generated by the tightening of the threaded fasteners. The ends of the fasteners cause the side clamp members 60 , 61 to move laterally (as shown in the direction of the arrow in FIG. 11 ) in the direction of the panel thereby making direct or indirect contact with the panel. This is shown in FIG. 11 where the threaded fasteners are screwed in the direction of the arrow shown. The clamp members 60 , 61 also enable the panel to be easily aligned to a desired position by adjusting of the threaded fasteners. Alternatively, the side clamp members 60 , 61 can be moved comply with the position of the panel.
Preferably, the width “W” of the slot of the housing 50 is greater than the thickness “X” of the base member 62 (which corresponds to the thickness of the panel). This can then allow for misalignment of the panel with the elongated direction of the slot 70 of the housing to be accommodated. This also allows the panel to be adjusted or aligned to a desired position. It also allows panels of various nominal thickness to be used by simply changing the thickness of the base member 62 .
In a preferred form, the positioning of the apertures allows the lower two pairs of threaded fasteners, when tightened, to provide most of the clamping forces on the panel. This allows the upper pair of threaded fasteners to be tightened less than the lower two pairs of threaded fasteners or alternatively to be sufficiently tightened without the use of a tool. Since the upper pair of threaded fasteners provides less clamping forces on the panel, the lateral stresses on the panel near the mouth of the slot of the housing are reduced. Also, the lateral stress on the housing at its upper region is reduced meaning that less deformation of the housing will occur.
The panel mount may also be mounted on a bracket 80 . This is shown in FIGS. 15 and 16 . The housing 50 may be affixed to the bracket 80 by directly engaging the underside of the housing 50 with one end of bracket 80 . Conventional means for affixing the housing 50 to the bracket 80 may be used such as for example a threaded fastener. The bracket 80 may be mounted on a fixed structure 75 for example a deck.
The bracket 80 includes at least an opening 81 to receive at least one fastener 84 to enable the bracket 80 to be mounted to a fixed structure 75 . Preferably, the opening 81 is an elongate slot to receive fasteners to secure the bracket to the structure in a direction perpendicular to the panel. Alternatively, the opening 81 may be at least one aperture to receive a fastener FIGS. 17 a - d show other variations. | This invention is a panel mount for non penetrative fastening of a panel (such as a glass pane). The panel mount has clamp jaws defining an elongate slot in which an edge of a panel can be received. A foot is provided for mounting and fastening the clamp jaws to a structure. At least one of the clamp jaws carries at least one threaded fastener that can be actuated by a user, including when the foot is fastened to the structure. The threaded fastener(s) of the at least one clamp jaw, in cooperation with the other clamping jaw, is capable of operatively clamping the panel to hold it in the slot, irrespective of any non-parallel disposition of the plane of the panel to the elongate direction of the slot. | 4 |
FIELD
[0001] This present invention relates to electrical connectors, and more particularly to a positive safety latch for making and unmaking a power connection.
BACKGROUND
[0002] In many electrical power environments, components and conductors are typically provided and installed in a modular manner, such that the various parts must eventually be mated, or electrically connected, with suitable connectors. In high-power or critical applications, it is important that the connectors be positive and reliable, while also allowing for a connection to be unmade if necessary.
[0003] By way of example, connectors used in the solar industry to connect photovoltaic (PV) modules in series utilize a latching system that require a tool to separate the mated connectors. This safety requirement is typical for single pole DC Solar connectors; however there is a need for a multi-pole AC Solar system that requires a tool for disconnection. This is especially true, for example, in applications involving micro-inverters.
[0004] The latching system must be rugged to withstand the harsh environment of solar applications, provide high durability for many mating cycles, be cost effective, and be easy for installers to make and unmake connectors.
[0005] Thus, it is an object underlying certain implementations of the described principles to provide a system for efficiently and effectively avoiding the above-noted problems where applicable. However, while this is an object underlying certain implementations of the invention, it will be appreciated that the invention is not limited to systems that solve the problems noted herein. Moreover, the inventors have created the above body of information for the convenience of the reader and expressly disclaim all of the foregoing as prior art; the foregoing is a discussion of problems discovered and/or appreciated by the inventors, and is not an attempt to review or catalog the prior art.
SUMMARY
[0006] In an embodiment of the invention, a multi-pole AC Solar system latch system is provided that provides safety via an internally hidden latch that requires a special tool or correctly sized pin to open. The described system is positive, in that it provides a “deadbolt” style latching. Pull out force is perpendicular to direction of opening the latch, and latching occurs on both sides of the locking post.
[0007] While unlatching the connection is made secure, the system is still very user friendly in that mating the two connectors does not require any tools. Mating is achieved with a simple straight forward insertion of the mating connector. The latch is captured inside the plastic unit housing, and a stamped sheet metal spring provides high cycle life. In an embodiment of the invention the lead-in construction provides a smooth surface for inserting the mating connector. Finally, the device is configurable, in that the spring thickness and width can be modified to optimize spring force in a given application.
[0008] Although various embodiments of the invention are applicable to multi-pole AC Solar system connections, other objects and advantages of the invention will become apparent upon reading the following detailed description and upon reference to the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is an external perspective view of a latch and its usage environment according to an embodiment of the invention, including a mating connector or cable assembly, connector body, and unlocking pins;
[0010] FIG. 2 is a schematic front elevation of the connector body;
[0011] FIGS. 3A-3D are enlarged images of a section of FIG. 2 showing the latch during use in an embodiment of the invention;
[0012] FIGS. 4A-4C are perspective views of the connector assembly during use in an embodiment of the invention;
[0013] FIG. 5 is a perspective view of the latched assembly of FIG. 4C with an unlocking tool inserted into matching guide holes in the connector body;
[0014] FIG. 6 is a perspective view of the latching spring according to an embodiment of the invention;
[0015] FIG. 7 shows a cross-sectional side view of the connector assembly according to an embodiment of the invention;
[0016] FIG. 8 is a perspective view of a latch spring according to an embodiment of the invention; and
[0017] FIG. 9 is an end view of the latch spring of FIG. 8 .
DETAILED DESCRIPTION
[0018] As noted above, in an embodiment of the invention, a latch system is provided that operates via an internally hidden latch that gives a “deadbolt” type latching, wherein the pull out force is perpendicular to direction of opening the latch, and latching occurs on both sides of a locking post. Other features will be appreciated from the following detailed description and figures. In an embodiment, the referenced connectors are specifically configured for a multi-pole AC Solar system, and the type and number of connections and conductors in such systems will be familiar to those of skill in the art.
[0019] Referring now to FIG. 1 , this figure shows an external perspective view of the latch in its usage environment. As shown, a mating connector or cable assembly 100 latches into a connector body 101 . In a further embodiment, unlocking pins 102 are provided within the connector body 101 .
[0020] FIG. 2 is a schematic front elevation of the connector body 101 ( 201 ). The connector body 201 includes internal locking springs 202 for latching onto locking pins of the mating connector assembly 100 ( FIG. 1 ). The connector body 201 also includes guides 203 for the locking pins, as well as guides 204 for the disconnect pins or tool, which requires access to the locking springs 202 to open them.
[0021] FIGS. 3A-3D are enlarged images of section 205 of FIG. 2 . Renumbered 305 , the enlarged section shows the internal locking spring 302 at rest ( FIG. 3A ), being spread open upon insertion of a locking pin 301 of the mating connector assembly 100 ( FIG. 3B ), latched around the barb end of the latching pins 301 ( FIG. 3C ), and being forced open by unlocking pins 304 ( FIG. 3D ).
[0022] FIGS. 4A-4C show the connector assembly 400 including locking pins 402 being inserted into the connector body (not shown except for locking springs 403 ). In FIG. 4A , the locking pins 402 are not yet in contact with the locking springs 403 . In FIG. 4B , the locking pins 402 are in contact with and are spreading open the locking springs 403 . Finally, in FIG. 4C , the barb portions 404 of the locking pins 402 have passed through the locking springs 403 , and the locking springs 403 have reclosed behind the barb portions 404 .
[0023] FIG. 5 shows the latched assembly of FIG. 4C with the unlocking tool 500 being inserted into the matching guide holes in the connector body 101 (not shown in FIG. 5 ). As can be seen, the pins 501 of the tool 500 are inserted to spread the latching springs 502 , so that they release the barb portions 503 of the latching pins. This allows the connector assembly 504 to be removed from the connector body.
[0024] FIG. 6 is a perspective view of the latching spring 600 . The latching spring 600 in the illustrated embodiment includes a formed lip 601 on both top and bottom to ease insertion of the locking pins of the mating connector (not shown), and to simplify insertion of the unlocking tool (not shown). A second formed lip 602 on top and bottom of the opposite side of spring 600 allows for easy insertion of the unlocking tool from this side alternatively. The flat bearing surface of the spring 600 interface with the locking pins of a mated connector (not shown).
[0025] FIG. 7 shows a cross-sectional side view of the connector assembly 100 , renumbered 700 . The cross-section is taken vertically through one of the latch pins. The connector assembly 700 includes a main body portion 701 and a pin portion 702 . The pin portion 703 further includes a barb portion 703 for interfering with and being locked by the prongs 704 of the locking springs.
[0026] FIGS. 8 and 9 show optional features that may be implemented within various embodiments of the invention. In particular, FIG. 8 is a perspective view of a latch spring 800 including rounded lead-ins 801 - 802 in place of all lips 601 - 602 , to avoid gouging of the connector housing wall. The perspective view of latch spring 800 also shows an optional cut-out 803 , configured to engage with a key, e.g., a molded plastic key, in the connector housing to ensure that the spring 800 will not rotate inside housing. FIG. 9 shows the same structure as FIG. 8 , albeit in an end view taken along direction A of FIG. 8 . FIG. 9 also shows the connector housing walls 804 .
[0027] Although the foregoing examples illustrate locking springs and pins at opposite sides of the assembly, it will be appreciated that the pair of locking elements may instead be located above and below the assembly, and/or that a single such locking element (latch spring and pin with barb) may be used, or that three or more such elements may be used. Although not specifically reiterated above, it will be appreciated that the described connection system is used to lock connector body and connector assembly together such that conductors in each are fixed into contact with one another. There may be one or more such conductors within each of the connector body and connector assembly, and each such conductor may carry power, signal, or both.
[0028] While the springs are preferably a metallic or other flexible material, the connector assembly and conductor body may be made of any suitable material having sufficient rigidity, moldability or formability and, if required by the application, sufficient insulating properties. Example materials for constructing these elements include plastic, e.g., thermo set or other plastic, resin, fiber-reinforced resins and plastics, and similar materials.
[0029] It will be appreciated that the foregoing description provides examples of a connection structure that is secure and user friendly, while maintaining a high cycle life and customizability through the size and strength of the included spring elements. However, it will be appreciated that other implementations of the disclosure may differ in detail from the foregoing examples. As such, all references to the disclosure or examples thereof are intended to reference the particular example being discussed at that point and are not intended to imply any limitation as to the scope of the disclosure more generally. All language of distinction and disparagement with respect to certain features is intended to indicate a lack of preference for those features, but not to exclude such from the scope of the disclosure entirely unless otherwise indicated.
[0030] Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context.
[0031] Accordingly, this disclosure includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the disclosure unless otherwise indicated herein or otherwise clearly contradicted by context. | An electronic connector latch system provides safety via an internally hidden latch that requires a correctly sized pin to open. The described system is positive, in that it provides a “deadbolt” style latching wherein the pull out force is perpendicular to direction of opening the latch, and latching occurs on both sides of the locking post. The system is still user friendly in that mating the two connectors together can be accomplished without any tools. Mating is achieved with a simple insertion of the mating connector. The latch is captured inside the plastic unit housing, and a stamped sheet metal spring provides high cycle life. | 7 |
This application is the national stage of International Application no. PCT/SE94/01183, filed Dec. 8, 1994.
The present invention relates to a new peptide, to a new diagnostic antigen comprising said peptide and a method of in vitro diagnosing an active infection caused by hepatitis C virus (HCV) which makes use of a diagnostic antigen according to the invention.
BACKGROUND
The hepatitis C virus is one of the most recently identified human pathogenic viruses, first described in 1989 (Choo Q-L, et al., Science 244:359-362 (1989); Kuo G, et al., Science 244:362-364 (1989)). HCV is one of the first of the viruses termed non-A, non-B viruses to be identified. HCV seems to have been the major cause for post transfusional hepatitis since the introduction of HBV screening at blood banks (Kuo, et al., ibid). The world wide spread of HCV has been shown to be similar to that of HBV. Several routs for parenteral infections have been shown, such as needlestick injuries, intravenous drug use, and through immune globulin preparations (Cariani E, et al., Lancet 337:850 (1991); Chamot E, Aquired Immuno Deficiency Syndrome 6:430-431 (1992); Horst H. A., N Engl J Med 325:132-3 (1991)).
HCV has a size of 30-38 nm and is a member of the flaviviridae with a RNA coded genome of approximately 9.5 kilo bases. Based on the homology, the HCV genome has been proposed to code for two or three structural proteins, core and envelope, and perhaps also a matrix protein (Takamizawa A, et al., Journal of Virology 65:1105-13 (1991)).
The structure of the HCV is yet unknown, it can only be assumed by the proposed homology with the other members of the flaviviridae. Proteins related to HCV have only been produced as recombinant constructs, and no complete HCV virion has been observed. The proteins are estimated to be translated at the following sizes: core 192 amino acids; possibly the 70 carboxy terminal of these is the matrix protein, which is based on the homology with members of the flaviviridae (Takamizawa, et al., ibid); the E1 192 amino acids, the E2-NS1 344 amino acids, the NS2 278 amino acids, the NS3 609 amino acids, the NS4 398 amino acids, and the NS5 998 amino acids.
The most variable regions of the HCV genome have been shown to reside within the probable envelope genes, whereas the 5' end and the core regions of the HCV genome seem to be highly conserved.
The main assays, so far, for studying the immunology of HCV has both in Europe and USA been the enzyme immuno assay (EIA) with the recombinant C-100 construct which covers parts of the NS4 protein (Kuo, et al., ibid). More recently assays containing either long synthetic peptides or recombinant peptides which cover both structural and non-structural HCV products, have been introduced (Hosein B, et al., Proc Natl Acad Sci USA 88:3647-51 (1991); Mimms L, et al., Lancet 336:1590-1 (1990)). The problems with the early, first generation, assays were both unsatisfactory sensitivity and specificity (Dawson G. J., et al., Journal of Clinical Microbiology 29:551-556 (1991)), though the second generation assays do seem to have improved the serology according to these problems (Chaudhary R. K., et al., J Clin Lab Anal 7:164-7 (1993); Chaudhary R. K., et al., Journal of Clinical Microbiology 29:2329-2330 (1991); Marcellin P, et al., Lancet 337:551-2 (1991)).
What is known about the immune response to HCV has mainly been obtained by using these assays. Most persons infected by HCV develop antibodies to one or more of the proteins, mainly the core and NS3/NS4 (Nasoff M. S., et al., Proc Natl Acad Sci USA 88:5462-6 (1991); Okamoto H, et al., Virology 188:331-341 (1992); Okamoto H, et al., Japanese Journal of Experimental Medicine 60:223-33 (1990); Sallberg M, et al., Immunology Letters 33:27-34 (1992); Sallberg M, et al., Journal of Clinical Microbiology 30:1989-1994 (1992)). Recombinant constructs covering these regions are termed c22 (core; Chiba J, et al., Proc Natl Acad Sci 88:4641-4645 (1991); Harada S, Journal of Virology 65:3015-21 (1991)), c33 (part of NS3), and C-100 (parts of NS3/NS4), and the C5-1-1 (a part of the C100-3 protein). The immune response to c22 and c33 have shortened the serodiagnosis of HCV in acute infections (Mattson L, et al., Scandinavian Journal of Gastroenterology 26:1257-1262 (1992)). No marker has been found to correlate to chronic infection, and IgM to different proteins have so far not been fully successful to be differentiating between acute and chronic infection. Only the persistant detection of HCV RNA by polymerase chain reaction (Garson J, et al., Lancet 335:1419-1422 (1990); Okamoto H, et al., Japanese Journal of Experimental Medicine 60:215-22 (1990); Weiner A. J., et al., Proceedings of the National Academy of Sciences USA 89:3468-3472 (1992)) has proven to be diagnostic for differentiating the acute from chronic carriers. One observation making HCV serology difficult is that seropositive individuals may loose their antibodies to HCV, or seronegative individuals may have HCV RNA. Immunity after HCV infection seems to be rather weak.
DESCRIPTION OF THE INVENTION
The present invention provides a new peptide of the formula ##STR1## wherein there is a disulfide bridge between the two cysteine residues (SEQ ID NO: 1).
This synthetic peptide (HCV-15) has been chemically synthesized and the amino acid sequence thereof is similar to the N-terminal amino acids 1-28 of the amino acid sequence disclosed by Takeuchi, K et al., in Nucleic Acid Research 18:4626 (1990). However, the peptide of the invention, HCV-15, has two cysteine residues at positions 8 and 20, respectively, instead of Gln, and has further a disulphide bridge between said two cysteine residues formed by a chemical oxidation step.
The invention is further directed to a diagnostic antigen in carrier-bound form comprising the peptide according to the invention, HCV-15. The carrier may be coupled to the peptide by any suitable technique known in the art. The term "carrier" should be interpreted broadly, and it may be a surface, such as microtiter plate, glass or plastic beads, an amino acid residue, a peptide or a protein, such as keyhole limpet hemocyanine, bovine serum albumin, poly-L-lysine or a combination of such carriers as long as the carrier does not destroy the ability of the peptide of the invention to bind to HCV antibodies.
The diagnostic antigen of the invention does not only detect antibodies directed to HCV in a sample of body fluid, such as blood, salive or urine, but makes it also possible to differentiate between past and ongoing infection.
Thus, the invention is also directed to a method of in vitro diagnosing an active infection caused by hepatitis C virus which comprises subjecting a sample of body fluid from an individual to be diagnosed to an immunoassay making use of a diagnostic antigen according to the invention followed by evaluation of the level of reactivity obtained, low levels indicating past infection and high levels indicating active infection.
There are several known immunoassay techniques which can be used, such as radioimmunoassay (RIA), enzyme immunoassay (EIA), blot assays, such as Western blot, and agglutination assays, such as latex, particle and hemagglutinin. The detection methods are different in the different types of techniques, making use of certain types of markers as appropriate, but all immunoassay techniques are based on antibody-antigen reactivity, i.e. the amount of such complexes formed in relation to a standard or negative sample.
The diagnostic antigen according to the invention has been found to detect antibodies to the HCV core protein in more than 94% of persons with antibodies to the HCV (see Table 1). When compared to an anti-HCV core reactivity detected by a commercial assay containing a recombinant HCV core protein, the sensitivity of the HCV-15 EIA assay was found to be 89%-95% (see Tables 1 and 2).
When the method of in vitro diagnosing an active infection caused by hepatitis C virus of the invention was used, it was possible to discriminate between active and past infection by determination of the level of reactivity. When testing 134 samples, out of which 129 were reactive in different commercial anti-HCV EIAs, 84 were found to be positive for HCV RNA by PCR. Out of these 84 sera, 75 were reactive in the HCV-15 assay. The reactivity to the HCV-15 peptide of the invention was found to be significantly related to the presence of HCV RNA, as determined by PCR (p<0.01; see Table 3).
Further, the mean level of reactivity in the HCV-15 assay was found to be significantly higher in samples containing HCV RNA detected by the polymerase chain reaction (see Table 4). Thus, a high level of reactivity to the HCV-15 peptide is a sign of ongoing HCV infection.
Due to the high predictive value for the presence of HCV RNA when using the diagnostic antigen of the invention in an immunoassay, the method of diagnosing an active infection caused by HCV according to the invention may function as a rapid surrogate diagnosis for determining ongoing infection (see Tables 3 and 4).
It should be mentioned that the diagnostic antigen of the invention, which is a single cyclized synthetic peptide, has a specificity which is comparable to the presently available anti-HCV assays using multiple peptides or multiple recombinant antigens (see Tables 3-5).
Synthesis of the peptide of the Invention
The peptide of the invention is first synthesized in linear form making use of a suitable method commonly known in the art, such as genetic engineering, or coupling of one amino acid residue to the next or coupling of shorter sequenses in proper order, whereby peptide bonds are formed between residues, until the whole linear peptide is built-up, either in liquid medium or on a solid support (so-called solid phase synthesis). Then the linear peptide is subjected to a chemical oxidation step for ring-closure between the two cystein residues, whereby a disulfide bond is formed.
The solid phase technique was used for the synthesis of the peptide of the invention in accordance with the following referenses:
Merrifield, R. B. (1963) J. Am. Chem. Soc. 85:2149
Merrifield, R. B. (1964) Biochem. 3:1385
Konig, W. & Geiger, R. (1970) Chem. Ber. 103:788
Sheppard, R. C. (1973) In Nesvadba, H. (ed) Peptides 1971, North Holland, Amsterdam p. 111
Atherton, E., Gait, M. J., Sheppard, R. C. & Williams, B. J. (1979) Bioorg. Chem. 8:351
Sheppard, R. C. (1986) Science Tools 33:9-16
Atherton, E. & Sheppard, R. C. (1981) In Eberle, A., Geiger, R. & Wieland, T. (eds) Perspectives in Peptide Chemistry, Karger, Basel p. 101.
In addition to established three-letter codes for the amino acids, the following abbreviations are used:
______________________________________Boc tert-butoxycarbonylDIPCDI diisopropyl carbodiimideDMF dimethylformamideEDT ethanedithiolFAB-MS fast atom bombardment mass spectrometryFmoc 9-fluorenylmethoxycarbonylHOBt 1-hydroxybenzotriazoleOtBu tert-butoxyPmc pentamethylchromansulfonylPOE polyoxyethylenetBu tert-butylTFA trifluoroacetic acidTrt triphenylmethyl______________________________________
All the amino acids used during the synthesis were protected by a Fmoc-group on the alpha-amino function. The following amino acids were protected in the side chain:
Thr(tBu), Ser(tBu), Asn(Trt), Cys(Trt), Lys(Boc), Asp(OtBu) and Arg(Pmc).
The Amino acid derivatives were purchased from CalBiochem NovoBiochem GmbH, Badsoden, Germany.
The peptide of the invention having the formula SEQ ID NO: 1: ##STR2## wherein there is a disulfide bridge between the two cysteine residues, was synthesized in accordance with the solid phase technique under continuous flow on a Milligen 9050 Peptide Synthesizer (Millipore Corp., Mass., USA) (Atherton, E., Sheppard, R. C. (1989) Solid Phase Synthesis A Practical Approach. Oxford, Oxford University Press.)
The resin used was of POE type with Rink-linker and a theoretical load of 0.23 meq/g (Rapp Polymer, Tubingen, Germany). The amino acids were activated with DIPCDI/HOBt in DMF and the N(alpha)-Fmoc group was removed by 20% piperidine in DMF. The product of the synthesis was dried in vacuum overnight. The peptide was then cleaved from the resin by treatment with TFA in the presence of EDT and phenol as scavengers (TFA:phenol:EDT 95:2.5:2.5). The TFA mixture and the peptide were precipitated by diethyl ether (100 ml) and filtrated. The precipitate was washed on the filter with additional diethyl ether (3×30 ml) and the cleaved-off peptide was extracted with water (100 ml). The extract was immediately diluted to a volume of 1 dm 3 with 20% acetic acid in methanol and was treated with a 0.1 mole/1 solution of iodine in methanol until a faint yellow colour persisted.
Dowex 1×8 ion exchanger in acetate form (3 g) (Biorad, Richmond, Calif., USA) was then added, and the mixure was filtrated. The filtrate was subjected to evaporation and the residue was lyophilized from water.
The product was isolated by liquid chromatography (reversed phase). The stationary phase in the column consisted of Kromasil, 100 Å, C 8 , 5 μ (EKA Nobel, Sweden; Hichrome Ltd, Reading, Berkshire, England), and the mobile phase was acetonitrile/water containing 0.1% of TFA. The samples collected from the coulmn were analyzed by an analytical HPLC (Varian 5500, Sunnyvale, Calif., USA) which was equipped with an analytical column having the same stationary phase as the above described one. Those fractions containing pure substance (HPLC analysis) were pooled and the solvent was evaporated. The product was lyophilized from water.
The final HPLC analysis was made on ready product. Purity (HPLC): 99.9%
The structure was confirmed by FAB-MS. M+H! + =3145 (M-Scan Ltd, Sunninghill, Ascot, Berkshire, England), and by amino acid analysis (AAA) (Malmo Allmanna Sjukhus, Institutionen for Klinisk Kemi, Malmo, Sweden).
______________________________________AAA:AA obtained calculated______________________________________Asp,Asn 3.93 4Arg 3.95 4Cystine 0.67 1Gly 3.16 3Lys 4.13 4Met 0.99 1Phe 1.01 1Pro 3.89 4Thr,Ser 3.84 4Val 1.00 1______________________________________
Detection of antibodies to HCV-15 by enzyme immunoassays (EIAs)
One-hundered μl of HCV-15 peptide was passively adsorbed overnight, at room temperature, to polystyrene microtiter plates (Nunc Maxisorb 96F Certificate, Nunc, Roskilde, Denmark) at a concentration of 10 μg peptide per mililiter of 0.05M sodium carbonate buffer, pH 9.6. Prior to addition of 100 μl human serum diluted 1:100 in phosphate buffered saline (PBS) containing 1% bovine serum albumin (BSA), 2% goat serum (Sigma Chemicals, St. Louis, Mo.), and 0.05% Tween 20 (dilution buffer), the plates were washed four times with PBS containing 0.05% Tween 20. The diluted human serum samples were incubated on the microtiter plate for 45 minutes at ±37° C. After additional washing to remove unbound material, 100 μl of alkaline phosphatase conjugated goat anti-human IgG diluted (A-3150, Sigma Chemicals) 1:1500 in dilution buffer, was added and incubated on the plate for 30 minutes at ±37° C. The plate was again washed to remove excess material, and 100 μl of dinitrophenylenediamine (1 mg/ml) was added to each well, followed by incubation on the plate for 30 minutes at room temperature (20°-22° C.). The enzyme reaction was then terminated by addition of 100 μl 1M NaOH to each well, and the absorbances were read at 405 nm using a double beam spectrophotometer. Absorbances exceeding the mean OD at 405 nm of at least 10 anti-HCV negative human sera by more than three times their standard devation were regarded as containing antibodies to the HCV-15 peptide.
TABLE 1______________________________________Relation between presence of antibodies to HCV in 2:nd generationAbbott EIA (Abbott, Chicago, Ill.) and presence of antibodies to HCV-15in 88 Italian sera (kindly provided by Dr. Armando Gabrielli, Ancona) No. of sera reac- tive in AbbottNo. of sera reac- anti-HCV EIAtive to HCV-15 + - total______________________________________+ 70 0 70- 4 14 18total 74 14 88______________________________________ p < 0.01, Fisher's exact test. Note: Sensitivity: 95% Specificity: 100%
TABLE 2______________________________________Relation between antibody reactivity detected by theHCV-15 peptide EIA and Abbott Supplemental assay in96 human sera provided by SBL, Stockholm. No. of sera reactive in Abbott Supplemental AssayNo. of sera reac- Positive Indeterminat Negativetive to HCV-15 S+/NS+ S+/NS- S-/NS+ S/NS- Total______________________________________+ 41 9 1 1 52- 1 4 4 35 44Total 42 13 5 36 96______________________________________ Sensitivity 98% 69% 20% 97% (Specificity) Abbreviations: S = bead coated with recombinant HCV core protein NS = bead coated with recombinant HCV NS3 and NS4 proteins Total sensitivity 85%
TABLE 3______________________________________Relation between the presence of HCV RNA and meansample to cut-off ratio (S/CO) in HCV peptide EIAs ofpositive reactions using human sera. No. sera MeanPeptide HCV positive S/CO P-valueEIA RNA in EIA ratio SD (Whitney-Mann)______________________________________HCV-15 + 75 6,17 2,29 0,0352 - 15 4,73 2,22______________________________________ Note: S/CO = the absorbance at 405 nm of the sample divided by the mean of the negative sera plus three times their standard deviation.
TABLE 4______________________________________Relation between presence of HCV RNA by PCR andantibodies to HCV-15 in 134 Swedish sera (kindlyprovided by Dr. Anders Sonnerborg, SMCL, Stockholm).HCV HCV-15RNA + - Total______________________________________+ 75 9 84- 15 35 50Total 90 44 134______________________________________ p < 0.01, Fisher's exact test. Note: Sensitivity: 89% Specificity: 80%
TABLE 5______________________________________Relation between Abbott Supplemental and Organon 2 in96 human sera obtained from SBL, Stockholm. No. of sera reactive inNo. of sera reac- Abbott Supplemental Assaytive in Organon 2 Positive Indeterminat NegativeEIA S+/NS+ S+/NS- S-/NS+ S-/NS- Total______________________________________+ 41 7 4 0 52- 1 6 1 36 44Total 42 13 5 36 96______________________________________ Sensitivity 98% 54% 80% 100% (Specificity) Total sensitivity: 87%
TABLE 6______________________________________Relation between HCV-15 and Organon 2 in 96 humansera obtained from SBL, Stockholm. No. of sera reactive in Organon 2No. of sera reac- anti-HCV EIAtive to HCV-15 + - total______________________________________+ 48 4 52- 4 40 44total 52 44 96______________________________________ Note: Sensitivity: 94% Specificity: 91%
__________________________________________________________________________SEQUENCE LISTING(1) GENERAL INFORMATION:(iii) NUMBER OF SEQUENCES: 1(2) INFORMATION FOR SEQ ID NO:1:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH: 28 amino acids(B) TYPE: amino acid(C) STRANDEDNESS: single(D) TOPOLOGY: both(ii) MOLECULE TYPE: peptide(ix) FEATURE:(A) NAME/KEY: Binding-site(B) LOCATION: 8..20(D) OTHER INFORMATION: /note="DISULFIDE BRIDGE BETWEENCYS IN POSITION 8 AND CYS IN POSITION 20"(xi) SEQUENCE DESCRIPTION: SEQ ID NO:1:MetSerThrAsnProLysProCysArgLysThrLysArgAsnThrAsn151015ArgArgProCysAspValLysPheProGlyGlyGly2025__________________________________________________________________________ | A peptide of the formula (SEQ ID NO:1) Met Ser Thr Ash Pro Lys Pro Cys Arg Lys Thr Lys Arg Asn Thr Asn Arg Arg Pro Cys Asp Val Lys Phe Pro Gly Gly, Gly wherein there is a disulfide bridge between the two cysteine residues, is described. Further, a diagnostic antigen in carrier-bound form comprising said peptide is disclosed. Said peptide may be used in a method of in vitro diagnosing an active infection caused by hepatitis C virus. | 2 |
BACKGROUND OF THE INVENTION
This invention relates generally to treatment of photographic film, and more particularly concerns removal of dust from film slide surfaces as well as elimination of static on such surfaces, so as to remove dust from film.
In the past, devices have been constructed which employe nuclear pellets to ionize air which is blasted over film. The cost of such equipment is objectionable, in view of the need for frequent replacement of the nuclear pellets, which are individually expensive.
SUMMARY OF THE INVENTION
It is a major object of the present invention to provide apparatus and method to overcome the above problems and heavy expense. Basically, the apparatus comprises:
(a) first means forming a cleaning zone to receive film passed through said zone,
(b) second means for passing streams of gas flowing toward opposite sides of the film as it passes in said zone,
(c) and third means for supplying ions of opposite polarity to said gas streams and in cyclically reversing polarity relation.
As will be seen, the third means includes circuitry for cyclically reversing the polarity of ions supplied to each of two gas streams, one gas stream flowing toward one side of the film and another gas stream flowing toward the opposite side of the film; the polarity of ions supplied to said one stream is positive when the polarity of ions supplied to the other stream is negative, and vice versa; fine wire clusters are provided to have ion dispensing tips at upper and lower sides of the cleansing zone; and a succession of half cycle voltages are applied to the tips exposed to each of said streams, and characterized in that the half cycles are alternately positive and negative to said tips.
In addition, means is provided for initiating said supply of ions when film is introduced into the cleansing zone; such means provides electromagnetic beams passing crosswise through said zone to be interrupted by the film in that zone, and effecting said initiation in response to said interruption; and typically four of the beams are passed through said zone, and causing the gas to flow into said zone to pass through two of said beams at one side of said zone and to pass through another two of said beams at the opposite side of said zone. Further, the third means may advantageously include cables in bars connected to opposite end taps of a transformer secondary coil which is center tapped to ground, and cable branches have ion dispensing terminal fine wire clusters exposed to the cleaning zone at upper and lower sides thereof.
As a result, much lower voltage is needed to effect the same degree of cleaning of film as in prior apparatus (i.e. about±1,400 VAC, as compared with prior then required voltage±4,000 VAC); and the apparatus is simpler, more rugged and more reliable, ensuring dust free, static free film negatives for printing and/or duplicating, without use of brushes or wipers.
These and other objects and advantages of the invention, as well as the details of an illustrative embodiment, will be more fully understood from the following specification and drawings, which:
DRAWING DESCRIPTION
FIG. 1 is a perspective view showing apparatus in accordance with the invention;
FIG. 2 is a side elevation, taken in section through the FIG. 1 apparatus;
FIG. 2a is an end elevation taken on lines 2a--2a of FIG. 2;
FIG. 3 is a vertical section taken on lines 3--3 of FIG. 2;
FIG. 4 is a plan view, looking downwardly, taken on lines 4--4 of FIG. 2a;
FIG. 5 is a section on lines 5--5 of FIG. 2a;
FIG. 6 is an enlarged fragmentary view taken in elevation on lines 6--6 of FIG. 4;
FIG. 7 is a section on lines 7--7 of FIG. 6;
FIG. 8 is a circuit diagram; and
FIG. 9 is a voltage polarity timing diagram, as applied to upper and lower ion dispensing tips.
DETAILED DESCRIPTION
In FIGS. 1-7, the apparatus 10 for treating photographic film 11 (which may include microfiche) includes a support 12 and means associated with the support defining a film treatment zone 13 in the shape of a recess having a front opening 13a and opposite side openings 13b. The latter are spaced apart laterally to pass the film through the zone 13 which typically has venturi shape as seen in FIG. 1. Such means may comprise upper and lower curved surfaces 14 and 15. Surface 14 is downwardly convex in end elevation as seen in FIG. 2a. Surface 15 is upwardly convex in elevation as seen in FIG. 2a. A support or body wall 16 closes the rear side of recess 13.
Means is also provided to supply streams of pressurized gas such as air or nitrogren to zone 13, and closely adjacent opposite faces of film 11 passing laterally through the treatment zone. See in this regard the travel direction indicated by arrows 20 in FIG. 1. Such means may include the upper duct 21 in the support body above zone 13, the lower duct 24 in the body below zone 13, and supply duct 22 in wall 23. A compressed air supply is indicated at 27, with lines 28 and 29 leading to ducts 22, 23 and 24 as indicated. Outlets from the branch ducts 21 and 24 appear at 21a and 24a facing a throat portion of zone 13. Accordingly, dust is swept off the upper and lower sides of the film as it passes through the zone 13. The gaseous streams tend to flow laterally beyond the recess ends 13b in FIG. 2a as indicated by arrows 30.
FIG. 2a shows two photoelectric beams 35 passing from generators 37 to detectors 36, at opposite sides of the throat region. Beams 35 pass through openings 25a in curved wall 25 and openings 26a in a curved wall 26 An additional and redundant pair of beams 35' is provided between generators 36' and detectors 37'. Upon interruption of either beam, as by entry of the film into recess or zone 13, an air supply motor 27a is activated, to drive the air supply pump (for example) whereby air is automatically supplied to zone 13 only when the film is in zone 13. An electrical connection from detectors 37 to the motor 27a is indicated at 38.
Also provided is apparatus to supply ions of opposite polarity to the gas streams flowing toward opposite sides of the film and in cyclically reversing polarity relation. Such means includes ion dispensing tips 40 and 41 exposed to the zone 13 and the air or gas streams in such zones. Downward facing tips 40 are supplied with high voltage as by main cable 42 and cable branches 43 extending downwardly through duct 21, and upward facing and projecting tips 41 are supplied with high voltage as by main cable 44 and cable branches 45 extending upwardly through duct 22. See FIG. 7 shows synthetic resinous and insulative, elongated bars 46 and 47 of rectangular outline that form ducts 21 and 22 and carry the cables, branches and tips located at the branch terminals. Multiple tips in the form of clusters of fine wires (platinum, for example) are formed to yield best results in terms of flooding the zone 13 with ions, and redundancy of tips to assure workability enhanced ion production.
Tips 40 extend in recesses 48 in bar 46, and tips 41 extend in recesses 49 in bar 47, those recesses formed between groups of the outlets 21a and 24a, as is clear from FIG. 6. Other recesses 50 and 51 in the bars receive the main cables 42 and 44, about which insulations resinous material 53 is filled in or potted, as seen in FIG. 7. If desired, small ports 57 and 58 may be formed in bars 46 and 47 to pass air about branches 43 and 45 to recesses 48 and 49, to sweep ions off the fine wire tips, and toward the opposite sides of the film.
Further, the ion supply means typically includes circuitry 70 (see FIG. 8, for example) for cyclically reversing the polarity of ions supplied to each of two of the gas streams, one stream or streams flowing toward one side of the film, and the other stream or streams flowing toward the opposite side of the film. Reference to FIG. 9 shows that high positive voltage 72 is supplied to the tips at the upper bar to peak at 72a, and then to the tips at the lower bar to peak at 72b, etc. in cyclic relation; and that high negative voltage 73 is supplied to the tips at the upper bar to peak at 73b, and then again to the tips at the lower bar to peak again at 73a, etc. Positive peaks 72a are opposite peaks 73a (i.e. occur simultaneously); and peaks 73b are opposite peaks 72b. Also, see cyclic nodes 72c and 73c occurring simultaneously, between the peaks. It is therefore seen that each side of the film, at the throat of the venturi where gas velocity streams are greatest, is successively and rapidly (60 Hertz for example) subject to oscillation of high voltage between positive and negative peaks, so that dust particles are subjected to optimized electrostatic field differentials. A succession of half cycle high voltages, alternately positive and negative DC, i.e. alternating DC pulses, are applied to the tips. This is important when it is considered that the film passes randomly closer to or further from one or the other of the two surfaces 14 and 15, near throat openings in the surfaces to pass the ions and air streams applied at 14e and 15e.
Circuitry to develop the high voltage wave forms 72 and 73 is shown in FIG. 8. It includes a transformer 80 having primary and secondary coils 81 and 82. The secondary 82 is center-tapped to ground, at 83. The end terminals 84 and 85 of the coil 82 are respectively connected at 42 and 44, and via resistors 88 and 89 to the emitters or tips, indicated at 40 and 41, and as described previously. The end terminals of the primary coil are connected, as indicated at 90 and 91, across the 60 cycle 120 volt line 92, switch 93 (relay for example) connected in line 91.
Supply circuitry for the phototransistors, described previously at 36 and 37, is indicated as including transformer 104, rectifier bridge 105, operational amplifier 106, and four lines 107 leading via resistors 108 and 109 to the beam generators 36 and 36' and the detectors (phototransistors) 37 and 37'. When any of the beams is interrupted by film passage, amplifier 106 causes flow of current in line 110, i.e. across lines 11 and 111, energizing the relay coil 113 and closing switch 93. This in turn effects ion transmission by emitters 40 and 41, as described.
A circuit board 120 is mounted at 121; and an ON/OFF switch appears at 122. | A method of cleaning film includes:
(a) providing a cleaning zone and passing film laterally through that zone,
(b) providing streams of gas flowing toward opposite sides of the film as it passes in said zone, and
(c) supplying ions of opposite polarity to the air streams and in cyclically reversing polarity relation. | 7 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to German Patent Application No. 202010006995.5, filed May 19, 2010, which is incorporated herein by reference in its entirety.
TECHNICAL FIELD
[0002] The technical field relates to a door locking system and a method for locking, in particular for emergency locking of motor vehicle doors, especially doors which are situated in the rear of the motor vehicle.
BACKGROUND
[0003] Motor vehicles, in particular passenger automobiles, typically have a central locking system, via which all vehicle doors are coupled to one another for simultaneous closing and opening. Sometimes, door locking systems for motor vehicles have automatic locking, which independently locks all vehicle doors of the vehicle as a function of the vehicle velocity, for example, typically above approximately 4 km/h. An open, or incorrectly closed or locked motor vehicle door is typically indicated to the driver of the vehicle in the dashboard via the onboard electronics. Displays of this type typically also provide an indication of which of the vehicle doors coming into consideration is incorrectly closed.
[0004] A system of this type is known, for example, from DE 10 2007 041 701 A1. This motor vehicle is equipped with central locking and with a display screen in the vehicle interior, the locking state of the central locking being able to be displayed using the display screen. Furthermore, a warning message can be output via the display screen, for example, if a door or hatch is not correctly locked or a window is not completely closed or another malfunction or a defect of the motor vehicle has occurred.
[0005] For motor vehicles, in the case of which rear doors are attached at the rear, therefore on the C column, it is further required that the rear doors may not be opened when the motor vehicle is in motion. Otherwise, a door which is only slightly open would be engaged by the travel wind and flung into its maximum open position. Therefore, special requirements are to be placed on the security of the closing and locking systems of such rear doors which are attached to the rear in the travel direction. Although known door locking systems function extremely safely and reliably, sufficient safety of the occupants is to be ensured for the rare case of a malfunction or a system failure of the locking system or the vehicle electronics.
[0006] In view of the foregoing, at least one object is to provide a door locking system having a failsafe or a redundant or additional opening safety catch, in particular for the rear doors of the motor vehicle. The door locking system, which is to be implemented as error-redundant, is to be able to be implemented with the least possible effort and costs. In addition, other objects, desirable features and characteristics will become apparent from the subsequent summary and detailed description, and the appended claims, taken in conjunction with the accompanying drawings and this background.
SUMMARY
[0007] The door locking system provided according to an embodiment is provided for a motor vehicle, in particular for a passenger automobile. It has a warning unit, which is implemented for generating a first warning signal as a result of a detection of a malfunction of the vehicle locking. The warning signal is only to be generated in this case if an error or a malfunction is detected in the predominantly electrically activated closing and locking system. For example, if those sensors assigned to the locking system, which are to detect the open or closed state of the particular vehicle door, do not function properly and transmit corresponding error signals to a control unit of the vehicle or the locking system.
[0008] The warning signal is to be generated at least if it can no longer be established with sufficient reliability whether the door locking system operates safely and reliably. The warning signal is to be implemented with respect to intensity and configuration in such a manner that it indicates the potential safety risks which could originate from the locking system particularly urgently to the driver of the motor vehicle. The warning signal is preferably penetrating and unpleasant enough that it keeps the driver from driving further. As a result, the driver will attempt to suppress the warning signal. The door locking system has a mechanism for this purpose, which is implemented to suppress the first warning signal, but makes this a function of the condition that at least one door opening safety catch of at least one motor vehicle door is manually activated.
[0009] The warning unit of the door locking system is therefore implemented for the purpose of announcing a malfunction or disturbance of the locking system by generating the first warning signal, which is to cause the vehicle occupants to manually activate a door opening safety catch. The warning unit is further implemented in this case for the purpose of suppressing the actual warning signal to be generated and/or deactivating its generation as a result of manual activation of a mechanical door opening safety catch. For this purpose, the door locking system preferably has a separate sensor system for ascertaining the status of the door opening safety catch. The sensor system or the control mechanism assigned thereto is to be implemented as independent and autonomous of the actual door locking system and/or independent of the vehicle onboard electronics for this purpose, so that in particular in the event of a malfunction of the door locking system, this redundantly provided warning mechanism can still function error-free.
[0010] According to another embodiment, it is provided that the first warning signal is implemented as an acoustically perceptible signal. The warning signal therefore preferably comprises a warning tone, which can sound as a periodically repeating warning tone and/or also as a continuous tone according to a further embodiment. It can also be provided for this purpose that a continuous tone to be generated immediately upon detection of the malfunction merges after a predetermined time into a signal which only repeats periodically.
[0011] According to a further embodiment, it is provided that the warning unit is further implemented to generate a second visually perceptible warning signal. The second warning signal can contain information about the type of the occurring malfunction, for example. For example, it can indicate that a malfunction is present in the door locking system. Furthermore, in certain circumstances, the second warning signal can specify in greater detail where and what precisely the detected malfunction consists of.
[0012] According to a further embodiment, it is further provided that the second warning signal is visually displayed in the dashboard of the motor vehicle.
[0013] In the case of a further embodiment, it is further provided that even after suppression of the first warning signal, the second warning signal remains activated, which preferably continuously signals to the driver that the door locking system is to be checked and possibly subjected to a repair in a workshop.
[0014] According to another embodiment, it is further provided that the door opening safety catch is implemented as a child safety catch, and all child safety catches of the motor vehicle are to be activated to suppress the first warning signal. A child safety catch which is provided in the rear doors of the motor vehicle anyway preferably functions as a door opening safety catch, which prevents opening of the particular vehicle door from the inside. Depending on the precision of the error acquisition, for example, if the warning unit is to be capable of specifying more precisely the door at which a malfunction has occurred, it can also be sufficient for the suppression of the first warning signal if only the door opening safety catch assigned to the affected door is activated.
[0015] According to a further embodiment, it is further provided that the vehicle doors equipped with a mechanical door opening safety catch have a display unit, which indicates an inactive door opening safety catch with generation of the first warning signal. This display unit is particularly attached on the interior and visibly on the motor vehicle interior trim. It can be implemented as a lighted or blinking LED, for example. In this manner, it is immediately and directly indicated to the driver of the vehicle upon occurrence of a system error which of the rear doors can currently still be opened from the inside and requires activation of its door opening safety catch or child safety catch.
[0016] According to another embodiment, it is further provided in this case that this door-specific display unit visually indicates the status of the door opening safety catch, and extinguishes this signal with activation of the mechanical door opening safety catch
[0017] According to a further embodiment, a method is provided for activating a door opening safety catch, comprising the steps of generating a first warning signal as a result of the detection of a malfunction of a motor vehicle door lock and manual activation of all mechanical door opening safety catches provided in the motor vehicle—if these are not yet to be activated—to suppress the first warning signal In addition thereto, it is provided that a second, preferably visually perceptible warning signal is generated with the first warning signal, which indicates that a malfunction of the door locking system exists. However, the second warning signal remains permanently activated with suppression of the first warning signal as a result of the activation of the door opening safety catch, until the disturbance in the door locking system is professionally remedied.
[0018] According to another embodiment, it is further provided in this case that an inactive door opening safety catch is visually indicated on the vehicle doors equipped with a mechanical door opening safety catch with generation of the first warning signal.
[0019] In a further embodiment, a motor vehicle is provided having an above-described door locking system. In a preferred embodiment, the motor vehicle has rear doors for this purpose which, viewed in the travel direction, are attached at the rear on the motor vehicle body and have a closing and locking mechanism which cooperates with the B column of the motor vehicle. The doors are linked on the vehicle body so they are pivotable in this case and are to be opened by a pivot movement to the rear directed opposite to the travel direction of the vehicle.
[0020] Although the locking system according to the embodiments is preferably used for rear doors of passenger automobiles which are linked so they are pivotable on the C column of the vehicle body, the use of the locking system is not solely restricted to those door configurations, but rather can be used universally in all motor vehicles having greatly varying vehicle doors.
BRIEF DESCRIPTION OF THE FIGURES
[0021] The present invention will hereinafter be described in conjunction with the following drawing figures, wherein like numerals denote like elements, and:
[0022] FIG. 1 shows five different states of the door locking system upon occurrence of a malfunction;
[0023] FIG. 2 shows a flowchart for the activation of the door opening safety catch; and
[0024] FIG. 3 shows a block diagram which illustrates the components of the door locking system and their interaction with one another.
DETAILED DESCRIPTION
[0025] The following detailed description is merely exemplary in nature and is not intended to limit application and uses. Furthermore, there is no intention to be bound by any theory presented in the preceding background or summary or the following detailed description.
[0026] The sequence of a typical method for activating the door opening safety catch or child safety catch is schematically illustrated in FIG. 2 . In first step 100 , as soon as the vehicle electronics detect a malfunction of the door locking system or for the case in which the door locking system sends an error code to the onboard electronics, a warning tone is generated by a control unit in following step 102 . Optionally, display units provided on the rear doors of the motor vehicle, such as LEDs, which signal the prevailing state of a child safety catch of the particular vehicle door, may be activated separately with generation of this warning tone.
[0027] An activation of an LED provided on the door internal trim, for example, is performed in step 104 . The generation of the warning tone 102 and the activation of a signal which further specifies the error in step 104 can be performed in sequence and also essentially simultaneously. The warning tone is preferably sufficiently unpleasant to the driver of the vehicle that he refrains from continuing driving and deals as soon as possible with the suppression of the warning tone. For this purpose, a mechanical opening safety catch, in particular a mechanical child safety catch, which is provided at least on the rear doors must be manually activated 106 . The required activation is detected in this case by a separate sensor system, which transmits a corresponding acknowledgment to the warning unit, as a result of which at least the warning tone is suppressed or deactivated in step 108 and the driver can continue driving extensively without impairment.
[0028] By engaging the child safety catch in step 106 it is ensured in any case that the rear doors may not be opened from the inside, so that opening of the door during travel, which is sometimes hazardous to the occupants, can be prevented. The generation of the warning tone can also be accompanied by generation of a visual warning signal, which is preferably indicated to the driver in the dashboard. This second warning signal symbolizes, for example, that a malfunction exists in the door locking system. The second warning signal remains active after suppression of the first warning signal implemented as a warning tone, however, and continuously reminds the driver of the vehicle that a professional workshop is absolutely to be sought out to remedy the malfunction of the locking system.
[0029] The tabular diagram according to FIG. 1 illustrates the typical sequence of a provided activation of the door opening safety catch on the basis of the states of individual units which generate warning signals. The five states A through E, which occur in chronological sequence, are listed in the first column. The second column illustrates the configuration of the vehicle doors, the warning signals and indicators 12 , 14 specified in the dashboard are listed in column 3 . The fourth column illustrates the display units 16 , 18 , which are provided on the rear doors and are preferably implemented as LEDs. Finally, the fifth column symbolizes the acoustically perceptible first warning signal 20 .
[0030] As soon as a malfunction of the door locking system of a motor vehicle is detected, the warning unit activates a second warning signal 12 and also a first warning signal 20 . While the second warning signal 12 is preferably represented in the dashboard in the form of a door symbol together with a warning notice, the first warning signal 12 is implemented as a continuous tone or as a repeating signal noise. The first warning signal 20 causes the driver to interrupt the travel immediately, to bring the vehicle to a standstill, and possibly to turn off the engine and the ignition.
[0031] In following step “B”, which is shown in the second line of the diagram according to FIG. 1 , the driver of the car opens the driver door provided on the front left. As a result, the door symbol 14 in the dashboard lights up. In addition, individual LEDs 16 , 18 on the rear doors are activated at latest in step “B”, which are to indicate a currently inactive child safety catch. The warning tone 20 still sounds in this case.
[0032] In a further embodiment, the LEDs may also be implemented independently and decoupled from the warning unit 32 , in that they only indicate an unlocked door and thus signal to the vehicle occupants, for example, that the door can be manually opened, for example, because of a vehicle velocity below a predefined limiting velocity of 4 km/h, for example.
[0033] In following step “C”, the vehicle occupant or the driver opens one of the rear doors and manually activates the mechanical child safety catch, as a result of which the LED 16 assigned to the rear left door is extinguished. In the present example, however, the child safety catch of the right door is still to be activated, because of which the warning tone 20 still sounds in step “C”.
[0034] In following step “D”, which corresponds to step 106 according to FIG. 2 , the further child safety catch provided on the right rear door is also activated. As a result thereof, the LED 18 assigned to the right rear door and also the warning tone 20 are extinguished.
[0035] In step “E”, the travel of the vehicle can now be continued, however, the second warning signal 12 remaining continuously activated and signaling to the driver that a malfunction exists in the door locking system. In any case, through the generation of a separate warning tone 20 , the activation of the child safety catch and a corresponding intervention of the driver of the vehicle would be caused, so that opening of the rear doors from the interior can be prevented for safety reasons for the travel, which is now to be continued.
[0036] A possible implementation of the door locking system is schematically shown in FIG. 3 . The door locking system has a control unit 32 , which is electrically coupled to an internal vehicle communication system 30 , such as a CAN bus or a similar onboard electrical system. The control unit 30 can electrically activate and deactivate a locking unit 38 provided in the vehicle door 36 in a direct manner. Additionally or alternatively thereto, it is conceivable that the activation of the locking unit 38 is performed by the control unit 32 indirectly via the onboard electrical system 30 .
[0037] However, if the control unit 32 establishes a system failure or an error code is transmitted thereto which indicates a disturbance of the door locking system, the control unit 32 functions as a warning unit and activates the generation of the warning tone via a loudspeaker 34 which is situated in the vehicle interior. The generation of the warning tone is triggered by the control unit 32 . The activation of the loudspeaker 34 is performed in this case via the onboard electrical system 30 , however, to which the loudspeaker, having an upstream communication module, such as a car radio, is connected. As an alteration thereof, it would further be conceivable to couple the communication module or its loudspeaker directly to the control unit 32 .
[0038] Independently and autonomously of the remaining vehicle electronics 30 , the vehicle door 36 has a mechanical door opening safety catch 40 , for example, in the form of a child safety catch, whose state is relayed to the control unit 32 using suitable electrical and/or mechanical sensors, for example. As soon as all child safety catches 40 of the vehicle doors 36 are activated and in this manner the rear doors of the motor vehicle are locked, the signal tone is suppressed or deactivated.
[0039] Furthermore, to identify the state of the door opening safety catch, a display unit 16 , 18 , for example, in the form of an LED, is provided locally on each vehicle door, which indicates the unlocked or locked state of the particular motor vehicle door to the vehicle occupants, for example, in normal and trouble-free vehicle operation. For the emergency locking system according to the invention, deviating there from, this LED 16 , 18 can function for indicating an active or inactive child safety catch.
[0040] No or only slight constructive adaptations of the door locking are required for the implementation of the door locking system. The generation of the first warning signal, which characterizes a potential safety-hazard malfunction of the door locking system, can be implemented in particular solely with software support.
[0041] The illustrated embodiment solely shows possible designs of the invention, for which numerous further variants are conceivable and in the scope of the invention. The exemplary embodiments shown for exemplary purposes are in no way to be understood as restrictive with respect to the scope, the applicability, or the configuration possibilities of the invention. The present description only indicates a possible implementation of an exemplary embodiment according to the invention to a person skilled in the art. Thus, greatly manifold modifications may be performed on the function and configuration of described elements, without leaving the protective scope defined by the following claims or its equivalents in this case. Moreover, while at least one exemplary embodiment has been presented in the foregoing summary and detailed description, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration in any way. Rather, the foregoing summary and detailed description will provide those skilled in the art with a convenient road map for implementing an exemplary embodiment, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope as set forth in the appended claims and their legal equivalents. | A door locking system is provided for a motor vehicle. The door locking system includes, but is not limited to a mechanical door opening safety catch and a warning unit configured to generate a first warning signal that is exclusively suppressed by a manual activation of the mechanical door opening safety catch. A motor vehicle is provided that includes, but is not limited to a vehicle body, a rear vehicle door that is linked on the vehicle body and facing away from a vehicle travel direction, the rear vehicle door configured to pivot, a door opening safety catch configured to be mechanically activate upon the pivot of the rear vehicle door, and a warning unit configured to generate a first warning signal that is exclusively suppressed by the mechanical activation of the door opening safety catch. | 4 |
FIELD OF THE INVENTION
This Invention relates to the construction trades in the fields of tile and masonry installations. More specifically, this invention relates to the preparation of an underlying substrate for the installation of tiled coverings.
BACKGROUND OF THE INVENTION
Many of the surfaces found in a modern building, are covered by tiled coverings such as ceramic tiles, slate tiles, decorative glass or mirror tiles or decorative mosaic tiles. The surfaces include floors, ceilings and walls inside the building, as well as floors, walkways, walls, pools and other similar surfaces outside the building. The installation of tiled coverings requires that the underlying substrate be prepared to provide a smooth, level and water-impermeable surface. The proper preparation of the underlying substrate requires significant skill and expertise. The current methods for preparation of the underlying substrate is very time consuming and laborious, increasing the time and cost associated with such installations.
In recent years there has been a significant trend towards homeowners performing maintenance, and even undertaking expansion projects, on their own without employing a professional. Numerous national and regional companies and stores cater to the owner-builders by providing products specifically designed for non-professionals. One area of home maintenance and construction that has largely remained the purview of professionals is the installation of tiled coverings, particularly on vertical surfaces. This is mainly due to the complexity of the traditional methods of installing tiled coverings.
In the current methods of installing tiled coverings, a substrate must be created to support the tiled coverings. There are two principal methods for creating the substrate: building up the underlying substrate or covering the underlying substrate with sheets of structural drywall.
When employing the first method, the preparation of the substrate begins by creating a moisture barrier by lining the area with lightweight building paper or similar material. Next, a combination of wire mesh, leveling sticks, and mortar is laid down over the moisture barrier. The wire mesh is cut into strips of proper size first and then nailed into place over the moisture barrier with special nails that incorporate a paper spacer. The result is that the mesh is stretched taught and spaced away from the moisture barrier. Wet mortar is then applied over the mesh. The mortar must be leveled and uniformly distributed over the entire surface. To assist in this process, one or more wooden strips are temporarily fastened to the surface. These wooden strips act as reference points for leveling the mortar to a uniform thickness. Once the mortar has been leveled, the wooden strips must then be removed and the resulting voids filled in. The final step is to attach the tiled coverings to the wet mortar and leveling the tiles individually to achieve a uniform and level appearance.
The use of structural drywall is an alternative to the procedure described above. Drywall is not as structurally sound as the method previously described, but may be acceptable depending on the type of installation. Water-resistant structural dry wall is generally available in rectangular sheets approximately 4'×8' feet in size. To be used as a substrate for installing tiled coverings, structural dry wall is first cut into strips of needed size and shape. The dry wall strips are then fastened to the underlying substrate with fasteners such as nails or screws. The tiled coverings are then attached to the dry wall strips. The main disadvantage of the use of dry wall as substrate is the lack of a moisture barrier. When exposed to moisture, dry wall material will decompose and lose structural integrity, leading to the failure of the installation.
In an attempt to reduce the susceptibility of the dry wall substrate installation to moisture, a concrete-type material has been substituted for the dry wall material using the dry wall installation method previously described. The main disadvantages of the concrete-type material for this type of installation are the high weight and the brittle nature of the material. The high weight of the concrete-type material makes it too heavy for certain applications such as prefabricated housing, mobile homes or marine applications. The brittle nature of the concrete-type material makes it difficult to cut or shape into proper-sized strips.
The installation of tiled coverings that are curved, or of irregular shape, creates significant challenges in the preparation of a substrate. For example, Radius tiles, tiles with a curved upper edge, are commonly used to create a decorative border at the base of a wall. When installing radius tiles, the substrate must be built up sufficiently to accommodate the curved edge of the tile. If the substrate is built up too much, a gap is created between the tile and the underlying substrate below the tile. If, the substrate is not sufficiently built up, the tile will not "sit" properly and the installation will be uneven and unsightly. Similar challenges exist for the installation of curved or irregularly shaped tiles.
The traditional methods for preparing an underlying substrate for the installation of tiled coverings require significant skill to execute properly. They are also time, and labor, intensive and unsuitable for non-professionals.
The difficulty inherent in the preparation of a suitable substrate for installation of tiled coverings has inspired attempts at facilitating certain aspects of the procedure. One such attempt is U.S. Pat. No. 2,852,932 issued in 1958 to S. J. Cable. The Cable '932 patent shows a tile and grouting assembly in which a frame or lattice is provided for retaining ceramic tiles in place. However, the Cable '932 assembly does not eliminate the need for extensive preparation of the substrate but merely eliminates the requirement for grouting between the tiles.
Another attempt in simplification of the installation of tiled coverings is seen in U.S. Pat. No. 3,521,418 issued in 1970 to Bartoloni. The Bartoloni '418 patent shows a pre-finished decorative rigid panel in which tiles are set on a fibrous backing that is impregnated by a plastic resin to bond the tiles to the backing support. However, while the Bartoloni '418 patented panel shows fixing of the tiles in a desired pattern, it may not adequately eliminate the need for preparation of an underlying substrate, especially if the panel is to be installed above a relatively flexible wooden floor and thereafter subjected to localized loading stresses. Also, the Bartoloni '418 patented tile panels do not include means for interlinking adjacent panels or absorbing stresses between adjacent panels.
Another approach can be found in U.S. Pat. No. 4,551,870 issued in 1985 to Presti, Jr. The Presti '870 patent shows a modular form used as a base for building shower stall thresholds. The form is constructed from two opposed former sections formed of light plastic material and adapted to have mortar poured in the space between the former sections. Tiles are attached to the outside of the former section by adhering them to mortar exposed through openings in the former sections. The approach of the Presti '870 patent is limited to constructing shower stall thresholds and the use of pairs of opposed former sections makes the approach unsuitable for direct installation of tiled coverings on flat surfaces. There is also no provision for attaching the former sections directly to the underlying substrate, making the use of mortar a necessary step of each installation.
A further approach to simplifying the installation of tiled coverings appears in U.S. Pat. No. 5,438,809 issued in 1995 to Gernot Ehlrich. The Ehrlich '809 patent teaches a modular flooring system consisting of units comprised of tiles affixed to a backing material and surrounded by a frame. Adjacent units are joined together by elongate strips. This approach, however is limited to installing tiles on horizontal surfaces, such as the floor. This approach relies on the existence of a frame to provide additional support to the tiles and is therefore unsuitable for trim tile installations which consist of one or two rows of tiles installed at the intersection of a wall and the floor or the coping of a swimming pool. Finally, the Ehlrich '809 patent does not address the installation of radius tiles.
Neither the traditional approaches, nor the approaches disclosed by the patents discussed above provide a general purpose product, or method, that can be used for the installation of tiled coverings directly on an unprepared surface.
Furthermore, the traditional approach of using sticks as leveling guides for leveling mortar applied to an underlying substrate is also time consuming and requires great skill to execute. The filling of voids and re-leveling of the mortar after the sticks are removed is a difficult and skill-intensive procedure unsuitable for non-professionals.
Therefore, the need exists for a product that facilitates the preparation of an underlying substrate for the installation of tiled coverings in a manner which reduces the time, labor and expense associated with the installation of tiled coverings and makes it possible for the homeowners who are not professional builders to successful complete tiled covering installation projects.
A further need exists for a product that provides a permanent, embedded leveling guide for wet mortar applied to a surface, which will eliminate the need for the use of temporary guides made from wooden strips.
SUMMARY OF THE INVENTION
It is an object of this invention to provide a product that may be used as a base for installing tiled coverings on an underlying substrate more easily and more efficiently than existing techniques.
It is a separate object of this invention to provide, in a preferred embodiment of this invention, a product that may be used as a base for installing curved-edge or "radius" tiled coverings more easily and more efficiently than existing techniques.
It is a separate object of this invention to provide, in a preferred embodiment of this invention, a method for installing tiled coverings, using the base easily and quickly.
This invention provides a way to install tiled coverings over a substrate quickly and easily using a base that is attached to the substrate and upon which the tiles are laid.
In one embodiment of this invention a base is provided, the base having a front and a back surface, one or more openings between the upper and lower surfaces, one or more fastening points to permit the attachment of the base to the underlying substrate, and one or more spacers on the lower surface of the base.
In a separate embodiment of this invention, the base includes one or more curved edges designed to cooperate with the curved edges of curved, or "radius", tiled covering.
In a separate embodiment of this invention, the base includes one or more interlocking connectors on one or more edges. The interlocking connectors of adjacent bases provide a positive connection between the adjacent bases enabling each base to provide mutual lateral support to its adjacent counterpart thereby increasing the lateral rigidity and stability of the overall installation.
In a separate embodiment of this invention, one or more bases are attached to the underlying substrate by mechanical fasteners, such as nails, screws or bolts. Mortar is then packed into the space between the base and the underlying substrate and permitted to extend through the openings to the front surface of the base. Tiled coverings are then attached to the mortar extending through the openings by pressing the tiled covering against the upper surface of the base.
In a separate embodiment of this invention, the base is attached to the underlying substrate by mechanical fasteners, and the tiled coverings are attached to the upper surface of the base using a mastic or adhesive compound. Using this method, no mortar is required for the installation of tiled covering.
It is a separate object of this invention to provide, in a preferred embodiment of this invention, a product that may be used as a permanently embedded leveling guide for wet mortar being applied to a surface, which leveling guide eliminates the need for using temporary guides during the leveling process.
In a separate embodiment of this invention, the base includes a ledge built on the front surface of the base to support the tiled coverings, or to provide a leveling guide for mortar.
In a separate embodiment of this invention, one or more bases incorporating a ledge are attached to the underlying substrate using mechanical fasteners. Mortar is then applied to the underlying substrate and the ledge of the base, or bases, attached to the underlying substrate is used as guide to level the surface of the mortar.
The invention and its particular features and advantages will become more apparent from the following detailed description considered in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the preferred embodiment for the base illustrating the front surface, the openings, the fastening points and the interlocking segments.
FIG. 2 is a perspective view of an alternative preferred embodiment of the base additionally featuring a curved edge.
FIG. 3 is a perspective view of an alternative preferred embodiment of the base, additionally featuring two curved edges.
FIG. 4 is a perspective view of an alternative preferred embodiment of the base, additionally featuring a ledge.
FIG. 5 is a perspective view of the back surface of the preferred embodiments, illustrating the spacers attached to the back surface of the base.
FIG. 6 is a planar view of an alternative embodiment of the base, featuring an adjustable spacer.
DETAILED DESCRIPTION OF THE INVENTION
This invention provides a base for the installation of tiled coverings on an underlying substrate, such a wall, floor, or a ceiling inside or outside a building, without the need for extensive preparation of the underlying substrate. Tiled coverings are any type of covering material that may be divided up into tiles and installed on a surface by placing the tiles adjacent to one another. Examples of tiled coverings include ceramic tiles, slate tiles, natural or artificial stone tiles, mirror tiles or decorative mosaic tiles.
The base comprises a backing that is generally rectangular in shape and provides the attachment point for the tiled coverings. The backing has a front surface (1) and a back surface (2). The tiled coverings are attached to the front surface of the backing, therefore the front surface of the backing is shaped to cooperate with the shape of the tiled coverings to be supported by the base. Flat tiles, for example would generally be placed on a flat front surface, while curved tiles would be best supported by a curved front surface. The back surface is usually shaped, in conjunction with the spacers described below, to cooperate with the underlying substrate. The backing is a portion of the base, therefore the front surface of the backing is also the front surface of the base and the back surface of the backing is also the back surface of the base.
The base is generally made from a material that is sufficiently rigid to support the weight of the tiled coverings without significant distortion, yet sufficiently light that the base may be easily transported and installed. Injection-molded plastic is typically used for manufacturing the base, however other strong and lightweight material, such as ceramics or composites or similar material may also be used.
The degree of rigidity of the base may vary based on whether mortar is used to install the tiled coverings. In an installation where mortar is used, when the mortar hardens, it imparts rigidity to the base and therefore the base may be made flexible to facilitate installation. If no mortar is used, the base itself must be sufficiently rigid to support the weight of the tiled covering without substantial deformation. The shape of the base and the distance between the front and back surfaces of the base may vary to cooperate with the shape, texture and weight of the tiled covering to be supported by the base as well as the material and contour of the underlying substrate. The color of the material from which the base is made may also be varied as required.
The two surfaces of the base are usually substantially parallel to one another. There are openings (3) between the two surfaces to permit the introduction of mortar and to reduce the weight of the base. The size of the openings should be large enough to permit easy introduction of mortar and small enough to retain the mortar packed between the back surface of the base and underlying substrate. The size of the opening, or openings, is also limited by their effect on the structural integrity of the base. The size and shape of the openings may be either uniform or varied.
One or more of the openings between the front and back surfaces of the base may be used as fastening points (4). Mechanical type fasteners such as nails, screws or bolts (10) may engage the underlying substrate through the fastening point and attach the base to the underlying substrate. The fastening points may be of the same shape and size as the openings between the front and back surfaces of the base, or they may be of a different size and shape. For economy of design and construction, the base may be manufactured such that substantially all openings between the front and back surface of the base may be used as fastening points.
The fastening points may be placed at intervals that correspond to the intervals of structural features in the underlying substrate which can support the base and the tiled coverings. Such features include studs and load bearing columns, and the interval between such features is generally regulated by local building codes or state or national regulations. The interval between the fastening points on the base, between adjacent bases, is keyed to the applicable codes and regulations regulating the placement of the structural features described above.
The spacers (8) are part of the back surface, projecting out from the back surface in the direction of the underlying substrate. When the base is attached to the underlying substrate the spacers contact the underlying substrate and maintain a gap between the back surface of the base and the underlying substrate. Generally, the spacers are uniform is size and distribution, although both the size and distribution of the spacers may be varied to permit the base to cooperate with the underlying substrate to align the upper surface of the base with the desired plane for the installation of the tiled coverings.
As shown in FIG. 6, the spacers may also consist of mechanical fasteners such as nails or screws attached to the underlying substrate and each having a top which supports the back surface of the base (9). The top of the mechanical fasteners forming the spacers in this embodiment may be sufficiently exposed through an opening in the base to permit the distance between the base and the underlying substrate to be adjusted during and after installation such that the front surface of the base may be placed in a desired plane irrespective of the contour of the underlying substrate.
During installation, the base is attached to the underlying substrate through attachment points built into the base. In one preferred embodiment, mortar may be introduced into the space between the base and the underlying substrate and the tiled coverings may be attached to the mortar presented at the openings on the base. The mortar fills the gap between the base and the underlying substrate and attaches to the tiled covering placed on the base. The mortar comes into contact with the tiled covering through the openings in the base. When the mortar hardens it creates a firm bond between the underlying substrate, the base and the tiled coverings. Although the use of mortar is not required in all installations, it may be employed when deemed advantageous.
In an alternative embodiment, after the base is attached to the underlying substrate, the tiled coverings may be attached to the base using a mastic or adhesive and the installation accomplished without mortar.
The tiled coverings adhere to the mortar that fills the space between the base and the underlying substrate and which is presented through the openings in the base. Alternatively a mastic can be used to adhere the tiled coverings directly to the front surface of the base, thus eliminating the need for mortar. Generally, however, any bonding agent, such as mastic, adhesive or mortar may be used to attach tiled coverings to the front surface of the base.
Bases can be placed adjacent to one another to cover a large surface. The bases can be manufactured in different shapes and sizes to accommodate various types of installations. The bases may be made from material of different color to match the tiled covering or mortar that is used in the installation.
The front surface of the base provides a clean surface, shaped to cooperate with the shape of the tiled coverings used. Flat tiles, for example would typically use a flat base for installation, while curved tiles would best be supported by a curved base.
The use of a base attached to the underlying substrate using mechanical fasteners eliminates the time consuming preparation of the underlying substrate required by the earlier methods. It permits relatively inexperienced individuals to install tiled coverings perfectly. In some installations, it eliminates the need to apply mortar to the surface. The elimination of mortar leads to a lighter, faster, easier and consequently more inexpensive installation.
Certain tiled coverings have a curved or `radius` edge or edges. For example, the tiles used to create a decorative border at the base of a wall have a curved upper edge. For the proper installation of radius tiles, both the flat body and the curved edge, or edges, of the tile must be adequately supported by the underlying substrate, or the base of this invention.
One embodiment of the base would include one or more curved edges designed to cooperate with the curved edge or edges of a radius tile. The curvature of a single edge makes this embodiment of the base, when viewed from the side, resemble the body of the letter "j". The curved edge may be manufactured to be integral to this embodiment of the base, or it can be manufactured as a separate section having the desired curvature that is attached to a base prior to, or during installation. The separate curved edge may also be installed separately on the underlying substrate without being attached to a base. When the curved edge or edges are manufactured as integral parts of the base, a weakened section may be provided to facilitate the separation of the curved edge from the base, if desired.
This alternative embodiment of this invention, (FIGS. 2 and 3) provides a base having one or more curved edges (6) to support the curved edges of radius tiled covering. The curvature of the curved edge, or edges, is designed to cooperate with the curved edge or edges of the tiled coverings installed on the base. Different curvatures are possible depending on the requirements of the tiled coverings being installed. Each curved edge of the alternative embodiment provides support for the corresponding curved edge of the tiled covering. The use of this embodiment eliminates the need to build up the underlying substrate to conform to the shape of the radius tiled covering, which is a far more complex and error-prone task than the preparation of the substrate for the installation of flat tiled coverings.
When a base of this invention includes a radius edge, all the advantages of the principal invention can benefit the installation of curved or radius-edged tiled coverings. The use of the base with a radius edge eliminates the need to prepare and build up the underlying substrate for the specific shape of the radius-edged tiled coverings. The use of this alternative embodiment permits installation of radius tiled coverings by relatively inexperienced individuals and achieving results hitherto obtained by experienced professionals only. The use of this alternative embodiment by a professional can significantly reduce the time and expense associated with the installation of radius tiled coverings.
An alternative embodiment of this invention includes a ledge (FIG. 4). The ledge (7) is part of the front surface of the base that is built up to a selected distance from the front surface. The ledge is generally built up to a right angle from the front surface of the base, although any other angle may be selected if desired. The ledge serves two discrete functions: it may be used to cooperate with the bottom edge of tiles attached to the base, or it may be used as a guide for leveling mortar. The ledge is generally made from the same material as the base itself, but if needed, it can be made from a different material to achieve a different degree of rigidity, different color or other unique properties required by the particular tiled covering or installation.
The use of a ledge to support the bottom edge of tiled coverings provides for a more convenient installation. When the tiled covering is attached to the base in substantially vertical orientation, the tiles are preferably supported while the mortar, or mastic, is drying. If the consistency of the mortar is not precisely controlled during the traditional installation techniques, the tiled coverings may simply fall off the wall before the mortar is dry. A support ledge prevents the tiled coverings from falling and gives the mortar or mastic a chance to adhere to the tiled coverings. In effect, the use of the base with the ledge makes the installation process more forgiving to errors, thus making it possible for individuals with relatively little experience to achieve professional-like results.
The preferred embodiment featuring a ledge may also be used as a leveling guide for wet mortar. In this application, the base is attached to the underlying substrate with mechanical fasteners such as nails, bolts or screws with the back surface facing the underlying substrate. The mortar is then applied to the underlying substrate, such as a wall or floor in sufficient depth to cover the base and the ledge. The tip of the narrow edge of the ledge can then be used as a guide to level the mortar using a straight edge, 2-by-4 plank or other suitable tool.
An alternative embodiment of the base includes interlocking segments along the edge of the base that permit each base to be securely connected to one or more adjacent bases. The typical interlocking mechanism is a tongue and groove connector, although other types of interlocking mechanisms may also be used. The interconnection of adjacent bases creates a more rigid overall surface for the installation of tiled coverings. The base of this invention may be manufactured in standard sizes and shapes. Preferably, the interlocking segments are standardized and would permit bases of different shapes and sizes to be attached to one another. The ability to attach adjacent bases of same or different shapes and sizes together allows great variety in the size, shape and contour of the area to be covered by tiled coverings. The use of interlocking segments preserves sufficient flexibility in the overall base surface to accommodate the normal flexing of the underlying substrate and the tiled covering while providing enhanced overall rigidity to the installation.
The features of various alternative embodiments of this invention may be combined in numerous variations to create bases for particular installations and requirements. For example, one such combination may consist of a base with curved upper edge and a ledge but no interlocking segments. Other variations are also possible combining the features described to form specific base configurations.
Although the invention has been described with reference to a particular arrangement of parts, features, steps and the like, these are not intended to exhaust all possible arrangements or features. Many other modifications and variations will be ascertainable to those skilled in the art. | A base is provided for the installation of tiled coverings on unprepared underlying substrates and a method for using the base. The base has two substantially parallel surfaces, openings to permit the introduction of mortar between the base and the underlying substrate, fastening points for the use of mechanical fasteners to attach the base to the underlying substrate, and fixed or adjustable spacers to keep the base in proper alignment with the underlying substrate. One or more curved edges may be added to accommodate curved-edged tiled coverings, interlocking segments may be added to provide additional lateral support and a ledge may be added to assist in supporting the tiled coverings or for leveling purposes. Mortar may be introduced into the space between the lower surface of the base and the underlying substrate through openings in the base and the tiled coverings are attached to the mortar presented at the openings. Alternatively, the tiled coverings may be attached to the base using a mastic or adhesive and the installation accomplished without mortar. | 4 |
BACKGROUND AND SUMMARY
The present invention relates to a method and an internal combustion engine system for keeping an exhaust gas aftertreatment system (“EATS”) within its working temperature range during an idle or motoring engine operation mode of an internal combustion engine, wherein the internal combustion engine is connected to the exhaust gas aftertreatment system and comprises a gas intake side and an exhaust gas outlet side, wherein the exhaust gas outlet side of the internal combustion engine is connected with the exhaust gas aftertreatment system via an exhaust gas duct and with the gas intake side via a connecting duct, the connecting duct providing a gas recirculation of the exhaust gas to the gas intake side of the internal combustion engine, and at least one valve controlling the recirculation of the exhaust gas. The present invention further relates to a computer program product related to said method above.
The present invention further relates to a retrofitting kit and a retrofitting method for retrofitting a vehicle having an internal combustion engine without any exhaust gas recirculation (EGR) possibility, namely a so called “non-EGR engine”, with a temperature control system for controlling the temperature in an exhaust gas aftertreatment system connected to the exhaust gas outlet side of the non-EGR engine, as well as a computer program product related to said method above.
At current and future emission levels for internal combustion engines in vehicles, particularly for heavy duty diesel engines, aftertreatment of the exhaust gas has increased in importance for both emissions and overall fuel consumption. Also drivability and dependability of the vehicles are affected by the different methods used to fulfill these emission standards.
One of the known methods is the use of a so called exhaust gas aftertreatment system usually in form of a catalyst or particle filter. These catalytic aftertreatment systems are operated within a suitable temperature range, for example 250° C.-450° C., which is easily maintained during normal driving conditions of a vehicle.
However, under certain operating conditions of an internal combustion engine the actual exhaust gas temperature is too low for said temperature range to be able to be maintained. These operating conditions are hereinafter referred to in the description and the claims as “idle or motoring engine operation modes” and are described more in detail in the following paragraphs.
The “idle engine operation condition” describes all engine operation modes, where the engine is running at idle speed. Idle speed is the rotational speed the engine runs on when the engine is decoupled from the drivetrain and the accelerator of the internal combustion engine is released. Usually, the rotational speed is measured in revolutions per minute, or rpm, of the crankshaft of the engine. At idle speed, the engine generates enough power to run reasonably smoothly and operate its ancillary equipment (water pump, alternator, and, if equipped, other accessories such as power steering), but usually not enough to perform heavy work, such as moving the vehicle. For vehicles such as trucks or cars, idle speed is customarily between 600 rpm and 1,000 rpm. Even if the accelerator is released, a certain amount of fuel is injected into the internal combustion engine in order to keep the engine running.
If the engine is operating a large number of accessories, particularly air conditioning, the idle speed must be raised to ensure that the engine generates enough power to run smoothly and operate the accessories. Therefore most engines have an automatic adjustment feature in the carburetor or fuel injection system that raises the idle speed when more power is required.
The “motoring engine operation mode” is defined as an engine operation mode, where the engine is running above a certain rotational speed (rpm), but no fuel is injected into the engine. One example of a motoring engine operation mode is when the engine is dragging, i.e. when a vehicle—which is normally driven by the engine—is coasting down a hill. During that mode the accelerator is also released, but the engine remains coupled to the drivetrain and the engine is kept running by the drive force of the gearbox main shaft.
During the above described idle or motoring engine operation modes, the engine is in principle pumping fresh air at ambient temperature to the exhaust system, whereby, disadvantageously, the exhaust gas aftertreatment system is “air cooled” in an uncontrolled (and unwanted) manner.
This in turn means that the temperature in the catalytic exhaust gas aftertreatment system drops rapidly below 250° C., so that an effective exhaust gas aftertreatment cannot be provided any more. It has therefore been suggested in the state of the art, to supply hydrocarbons (i.e. fuel) to an oxidation catalyst arranged in the exhaust gas stream for increasing the temperature of the exhaust gas, in order to maintain the temperature in the exhaust gas aftertreatment system. For that it is necessary to raise the average temperature of the oxidation catalyst during normal driving. This means that the hydrocarbons have to be injected into the oxidation catalyst while the temperature of the oxidation catalyst is higher than 250° C. to compensate for periods when the engine is in an idle or motoring engine operation mode. Therefore, this method causes an increase in fuel consumption and, consequently, an increase in fuel consumption costs.
Additionally, if the temperature of the exhaust gas stream is too low, more hydrocarbons (i.e. fuel) are needed in order to maintain the temperature in the exhaust gas aftertreatment system. Increased emission control requirements have therefore often resulted in a loss of efficiency of the internal combustion engine. It is therefore important to provide methods which allow effective exhaust emission control without adversely affecting the efficiency of the engine and the overall fuel consumption of the vehicle.
Beside the use of exhaust gas aftertreatment systems, a further possibility to reduce the emission of the combustion engine, particularly the quantity of nitrogen oxide in the exhaust gases, is a recirculation of exhaust gases, so-called EGR (Exhaust Gas Recirculation). Thereby, a part of the total exhaust gas flow of the internal combustion engine is recirculated. Internal combustion engines equipped with such EGR systems are also called “EGR engines”. The recirculated sub-flow of exhaust gas is cooled before fed into the gas intake side of the EGR engine, where it is mixed with incoming air before the mixture is introduced into the cylinders of the EGR engine. Cooling of the recirculated exhaust gas is a prerequisite for the EGR engines as recirculating hot exhaust gas would increase the temperature of the gas at the gas intake side of the EGR engine to a level which could damage the EGR engine. Moreover, recirculation of exhaust gas amounts in the range of 15-30% of the total mass flow through the EGR engine is required for yielding a sufficient NOx reduction.
In WO2007/032714, it has been suggested to use in an EGR engine, i.e. in an internal combustion engine system equipped with an EGR-system, the recirculated exhaust gas stream to maintain the temperature in the exhaust gas aftertreatment system. Since, as described above, maintaining the temperature is mainly a problem occurring during idle or motoring engine operation modes, it has been suggested to first detect that neither the braking system nor the throttle control mechanism of the vehicle is activated and that the vehicle is being driven at a speed in excess of a predetermined speed limit. Provided such conditions are detected, in the known system the exhaust gas flow through the EGR recirculation duct is then regulated with the help of an EGR valve arranged in the EGR recirculation duct in such a way that the main exhaust gas flow to the exhaust gas aftertreatment system is reduced to a level which is substantially less than 50% of said main exhaust gas flow to the exhaust aftertreatment system when the EGR valve in the EGR recirculation duct is closed. Due to the significant reduction of exhaust gas streaming through the exhaust gas aftertreatment system during these motoring engine operation modes, heat losses in the exhaust aftertreatment system are prevented.
Disadvantageously, the described method cannot be used for “normal” internal combustion engines having no exhaust gas recirculation means, i.e. so called “non-EGR” engines. These engines are widely used for vehicles having emission levels less than required for instance by the EURO 5 standard. A further drawback is that EGR systems comprise a plurality of elements, e.g. valves, sensors, exhaust gas cooler etc. which control the operation of the EGR engine and the amount of recirculated exhaust gas. These control systems are rather complex in their structure and operation already without such further control mechanism described in WO2007/032714. The implementation of such an additional control mechanism would increase the malfunction probability of the complete system of an EGR engine and also the overall cost of said system.
It is desirable to provide a simple and cost-effective temperature control method and system for use with a non-EGR engine which provides a possibility to keep the exhaust gas aftertreatment system within its working temperature range without increasing the fuel consumption and deteriorating the engine's efficiency.
The present invention, according to an aspect thereof, is based on the idea to connect an exhaust gas outlet side of a non-EGR engine with a gas intake side of the engine by means of a connection duct for recirculating exhaust gas from the exhaust gas outlet side of the engine to the gas intake side of the engine only during idle or motoring engine operation modes, and to control the recirculation of the exhaust gas only in dependence of a temperature of the gas sensed at the gas intake side of the engine and/or of the exhaust gas during idle or motoring engine operation modes of the engine. The advantage of this solution is that the internal combustion engine does not only pump fresh air at ambient temperature to the exhaust gas aftertreatment system, but a mixture of air and recirculated hot exhaust gas. Consequently, the unwanted forced cooling effect due to the fresh air in the exhaust gas mixture entering the exhaust gas aftertreatment system is considerably reduced and the exhaust gas aftertreatment system is kept within its working temperature range during the periods wherein the internal combustion engine is in an idle or motoring engine operation mode.
In contrast to the design and operation of known EGR engines, in the present invention the connection duct provides a recirculation of exhaust gases during idle or motoring engine operation modes only. Of course, due to the design of the inventive internal combustion engine system, one could think of recirculating a certain amount of exhaust gas even during “normal” engine operation modes of said engine, i.e. during engine operation modes other than idle or motoring engine operation modes, but this kind of recirculation is not sufficiently controlled for qualifying as emission control by means of an EGR engine.
As soon as the accelerator of the vehicle (for instance the gas pedal) in the present invention is activated, the recirculation of exhaust gases of the non-EGR engine is terminated, that means in particularly that the connection duct is closed so that exhaust gas cannot be recirculated anymore. This in turn means that a NOx reduction due to EGR—as provided with EGR engines—is not intended with the present invention and may only occur accidentally. Further, a sophisticated cooling and controlling of the amount of recirculated exhaust gas, which is necessary for the NOx reduction reactions taking place in EGR engines during normal engine operation modes, is not possible with the present invention.
NOx reduction can only be performed at relatively low temperatures. The higher the combustion temperature is the higher is the NOx amount. The recirculation of exhaust gas reduces the oxygen amount which in turn decreases the combustion temperature. However, recirculation of uncooled exhaust gas (as used in the present invention) increases the temperature in the engine and therefore contradicts the desired NOx reduction process used in EGR engines. Consequently, this has to be avoided for the known EGR engines. Additionally, in the present invention exhaust gas is recirculated only during idle or motoring engine operation modes and not during “normal” engine operation modes, i.e. during engine operation modes other than idle or motoring engine operation modes, so that a NOx reduction cannot be achieved.
As mentioned above, in the present invention, exhaust gas recirculation is performed solely during idle or motoring engine operation modes. This in turn means that neither a cooler in the connection duct nor a sophisticated control of the exhaust gas recirculation is required. Consequently, the recirculated exhaust gas is not cooled as required for EGR engines, but simply recirculated “as it is”. In one of the simplest embodiments of an aspect of the invention, the connection duct can be equipped with a simple on/off valve which opens the connecting duct during idle or motoring engine operation modes and closes in all other engine operation modes. For not damaging the internal combustion engine due to too high temperatures, the temperature of the gas at the gas intake side of the combustion engine and/or of the exhaust gas is sensed, and in case the sensed gas temperature exceeds a predetermined temperature threshold, the connection duct is closed, even if the combustion engine is still running in idle or motoring engine operation mode.
According to a further preferred embodiment, the exhaust gas duct is additionally equipped with a pressure control valve, which is controlled to at least partly close if the engine is in an idle or motoring engine operation mode. In this embodiment, the pressure control valve has at least two functions:
i. It reduces the total amount of exhaust gas flowing into the exhaust gas aftertreatment system, whereby an inflow of “cooling” exhaust gas into the exhaust gas aftertreatment is reduced, and ii. The pressure increase generated upstream of the pressure control valve by at least partly closing the valve propels the recirculation of the exhaust gas and preferably determines the amount of the exhaust gas that is supposed to be recirculated to the gas inlet side of the combustion engine.
According to a further preferred embodiment, in order to measure the gas temperature use is made of a temperature sensor which can be arranged for instance at gas intake side of the engine for sensing the gas temperature at the intake manifold of the engine and for controlling the recirculation of the exhaust gas.
As indicated above, keeping the aftertreatment system within its working temperature range during idle or motoring engine operation modes is achieved by two main concepts or, in a further development, by the combination of them:
i. Due to the recirculation of the uncooled exhaust gas, the operating temperature of the engine and thereby the overall temperature of the exhaust gas is increased, whereby the—unwanted—air cooling effect of the exhaust gas aftertreatment system during idle or motoring engine operation modes of the engine is reduced. ii. Due to the at least partly closed pressure control valve arranged in the exhaust gas duct, the amount of exhaust gas flowing through the aftertreatment system during idle or motoring engine operation modes of the engine is reduced and the amount of recirculated exhaust gas to the engine may be controlled, which in turn also reduces the—unwanted—air cooling effect of the aftertreatment system during idle or motoring engine operation modes of the engine.
In contrast to known EGR engines, the inventive method and system can also be used for retrofitting existing non-EGR engines, since it does not influence the “normal” operation of the engine. This can be done by simply connecting the exhaust gas duct with an induction duct arranged at the gas intake side of the internal combustion engine by a connecting duct and arranging a gas recirculation valve, preferably in form of an on/off valve, in the connecting duct and, preferably, also arranging a pressure control valve in the exhaust gas duct. Vehicles that are equipped with non-EGR engines and that are capable of being retrofitted with a system according to an aspect of the invention usually comprise already a temperature sensor and a controller for controlling valves in dependence of the gas temperature and the engine operation mode which can be directly used for the inventive method and system.
It should be noted that since uncooled exhaust gas is fed to the gas intake side of the engine, the temperature of the gas at the gas intake side of the engine and consequently the temperature inside the internal combustion engine also increases. In order to not damage the engine, supply of uncooled exhaust gas is controlled in dependence on the sensed temperature of the gas at the gas intake side of the internal combustion engine and/or of the exhaust gas. As soon as the temperature of the gas at the gas intake side and/or the exhaust gas exceeds a certain predetermined maximum temperature, supply of the exhaust gas is stopped or at least reduced until the sensed temperature of the gas at the gas intake side and/or the exhaust gas is again below the predetermined maximum temperature. This reduction or stop of the flow of recirculated exhaust gas may be achieved in that (i) the pressure control valve is opened completely or at least more than before the temperature of the gas at the intake side and/or the exhaust gas has reached its maximum temperature and/or (ii) the gas recirculation valve is at least partly closed or completely closed for certain time periods or time intervals, even if the engine is still in the idle or motoring engine operation mode. This in turn means that in such specific situations—where, due to the temperature of the hot recirculated exhaust gas, the actual temperature of the engine increases and gradually approaches, or even starts to exceed, the allowable maximum temperature of the engine—more of the exhaust gas or, in the extreme case, all of the exhaust gas will be forwarded to the EATS, which in turn may temporarily cool down the EATS to lower temperatures—in the worst case even to a temperature below its working temperature range. However, since the temperature of the internal combustion engine is relatively hot compared with the working temperature range of the EATS even in these specific situations, also the exhaust gas of the engine is expected to remain sufficiently hot. Consequently, even in situations where the recirculation of the exhaust gas has to be temporarily stopped or reduced during idle or motoring engine operation modes, an excessive cooling down of the EATS is rather unlikely to happen. As soon as the temperature of the internal combustion engine returns to its predetermined working temperature range, and provided the engine is still in the idle or motoring engine operation mode, the process of recirculating exhaust gas is restored.
As mentioned above, the recirculated exhaust gas flow is controlled by an appropriate control of the at least one valve, preferably the gas recirculation valve and the pressure control valve in dependence on the sensed temperature. Preferably, the gas recirculation valve may remain open during idle or motoring engine operation modes and the amount of exhaust gas recirculation and thereby the temperature of the gas at the gas intake side of the engine and/or of the exhaust gas may be controlled by the opening or closing degree of the pressure control valve. This type of feed back control of a valve or flow is often called “closed loop control”.
According to a preferred embodiment of an aspect of the invention, the gas recirculation valve is a simple on/off valve, which is either open or closed. The advantage is that a simple on/off valve is easy to control, cheap in use, and robust. Thereby the malfunction probability of the system is decreased.
Additionally, since the amount of exhaust gas flow recirculated to the engine does not need to be controlled as in normal EGR systems, a simple on/off valve that is normally closed is sufficient.
However, it goes without saying that, instead of a simple on-off valve, also a controllable valve could be used, the opening of which is continuously adjustable between completely closed and completely open.
According to a further preferred embodiment, the predetermined maximum temperature of the intake manifold at the gas intake side of the engine is approximately between 100° Celsius and 150° Celsius, particularly approximately between 110° Celsius and 130° Celsius, and preferably approximately 120° Celsius. Thereby, it is ensured that the internal combustion engine is not damaged.
According to a further preferred embodiment of an aspect of the invention, the pressure control valve arranged at the exhaust gas duct is adapted to reduce the gas flow to the exhaust gas aftertreatment system by circa 20% to 70%, preferably circa 30% to 60%, and most preferred circa 40% to 50%. Due to this reduction of total gas flow through the aftertreatment system, the “air cooling” effect of the aftertreatment system is reduced.
How much the gas flow to the exhaust gas aftertreatment system is reduced is preferably dependent on the engine speed and the sensed gas temperature at the intake manifold at the gas intake side of the engine and/or the exhaust gas. In general, the aim is to maximize the exhaust gas flow recirculated to the engine without exceeding the maximum temperature of approximately 120° C. at the gas intake side of the engine. Then, the flow to the exhaust gas aftertreatment system is minimized and the exhaust gas temperature is maximized. To do this, the above described “closed loop control” is used, preferably in form of software, to control the amount of recirculated exhaust gas by means of the pressure control valve in such a way that the gas at the gas intake side of the internal combustion engine reaches—but does not exceed—the permitted maximum temperature (here: for instance approximately 120° C.).
Preferably, the gas recirculation valve is closed as soon as an accelerator of the vehicle (for instance the gas pedal) is activated, and it is opened as soon as the accelerator is released. The control of the gas recirculation valve in dependence of the activation of the accelerator is a simple and effective control mechanism covering both the idle engine operation mode and the motoring engine operation mode. Preferably, at low idle speeds, e.g. around 600 rpm, and no accelerator demand, in addition to the recirculated exhaust gas, fuel is injected into the combustion engine for keeping the engine running.
According to a further aspect of the present invention, vehicles having non-EGR engines can be easily retrofitted with the inventive system for maintaining the temperature in the exhaust gas aftertreatment system. Thereby, an already existing exhaust gas aftertreatment system or a retrofitted exhaust gas aftertreatment system can be used. For retrofitting the non-EGR engine a retrofitting kit can be provided which may comprise a system for keeping the exhaust gas aftertreatment system within its working temperature range, comprising at least a connection duct for the recirculation of the exhaust gas which can be connected to the exhaust gas outlet side of the internal combustion engine (for instance to an exhaust gas duct arranged at the exhaust gas outlet side of the engine) and the gas intake side of the engine (for instance an induction duct arranged at the gas intake side of the engine), wherein a gas recirculation valve is arranged at the connection duct, and a controller for controlling the valve in the above described manner. Further, the controller can also be in form of a computer program which is intended to run on a vehicle's on-board computer.
Additionally, a pressure control valve may be provided for being arranged at the exhaust gas outlet side of the engine (for instance at the exhaust gas duct arranged at the exhaust gas outlet side of the engine). Further, a controller may be provided which is adapted to control the gas recirculation valve to open and the pressure control valve to at least partly close in such a way that—if the combustion engine is running in either an idle or the motoring engine operation mode—the temperature of the gas at the intake side of the engine and/or of the exhaust gas is kept or maintained within a predetermined temperature range.
In case the vehicle is not equipped with a temperature sensor, the retrofitting kit may also comprise a temperature sensor for sensing the temperature of the gas at the gas intake side of the engine and/or of the exhaust gas.
According to a further embodiment of an aspect of the invention, the controller of the retrofitting kit can be an already existing central processing unit (CPU) or electronic control unit (ECU) in the vehicle, particularly an onboard computer which is programmable to control the valves according to the above described way. A “CPU” is the portion of a computer system that carries out the instructions of a computer program. Particularly, in automotive electronics the term “ECU” is used as a generic term for any embedded system that controls one or more of the electrical systems or subsystems in a vehicle.
According to a further aspect of the invention, a computer program product is provided, which comprises a software code to be implemented on a computer, preferably on an on-board computer of the vehicle, so that the computer is adapted to perform the above described method steps. Preferably, the computer program product can be part of the retrofitting kit.
Further advantages and preferred embodiments are defined by the attached claims, the description and the Figures.
BRIEF DESCRIPTION OF THE DRAWINGS
In the following preferred embodiments of the system according to the invention will be discussed with the help of the attached Figures. The description of the Figures is considered as simplification of the principles of the invention and is not intended to limit the scope of the claims.
The Figures show:
FIG. 1 : a schematic illustration of a first preferred embodiment of the inventive system;
FIG. 2 : a schematic illustration of a second preferred embodiment of the inventive system; and
FIG. 3 : a diagram showing the temperature the exhaust gas aftertreatment system during an emission level test cycle with and without application of the inventive method.
In the following same elements or similarly functioning elements are indicated with the same reference numerals.
DETAILED DESCRIPTION
In the schematic representation of FIG. 1 an internal combustion engine system 100 is shown which is used in a vehicle (not shown), for example in a truck or bus, or in any other vehicle comprising an internal combustion engine. The engine system 100 comprises an internal combustion engine 1 with an engine block 2 having e.g. six piston cylinders 4 . Further, the internal combustion engine 1 has a gas intake side 5 with an intake manifold 6 and an exhaust gas outlet side 7 with an exhaust manifold 8 . The exhaust gases are led to a turbine 10 and onward through an exhaust duct 12 to an exhaust gas aftertreatment system 14 .
The exhaust gas aftertreatment system 14 can be e.g. a particle trap or a catalyst, as for example an SCR unit (Selective Catalytic Reduction unit). A SCR unit is a means for converting nitrogen oxides by means of a catalyst into nitrogen and water. An optimal temperature range for these reactions is typically between approximately 250° Celsius and approximately 450° Celsius. This optimal operating temperature can be easily kept during normal (driving) operation modes of the engine.
However, during idle or motoring engine operation modes of the engine 1 , the temperature of the exhaust gas drops. The reason for that is that air provided by a compressor 16 and cooled by a charge air cooler 17 , which re-cools the air after the compression process of the compressor 16 , is fed to the intake manifold 6 of the engine block 2 by an induction duct 18 , even if combustion is reduced considerably (as in the idle engine operation mode) or no combustion takes place at all (as in the motoring engine operation mode). This in turn means that the engine 1 is simply pumping fresh and cool air into the exhaust duct 12 and onward into the exhaust gas aftertreatment system 14 . This cool air causes the exhaust gas aftertreatment system 14 to cool down rapidly below its optimal operating temperature, which in turn results in poor or no exhaust gas purification, so that the required emission levels cannot be achieved.
According to an aspect of the invention, the preferred embodiment shown in FIG. 1 has a connection duct 20 which connects the exhaust gas duct 12 and the induction duct 18 . In this embodiment the connection duct 20 is branched off from the exhaust duct 12 downstream of turbine 10 .
However, the connecting duct 20 can also be branched off at the exhaust manifold 8 upstream of turbine 10 as shown in the second preferred embodiment of FIG. 2 . Regardless, where the connecting duct 20 is branched off, the operation of both embodiments shown in FIGS. 1 and 2 is the same.
It should be noted that it is also possible that in the internal combustion engine systems 100 shown in FIGS. 1 and 2 the turbine 10 can be omitted.
As can be further seen in FIG. 1 and FIG. 2 , a gas recirculation valve 22 is arranged at the connection duct 20 , which is preferably a simple on/off valve that is normally closed. Additionally, at the exhaust duct 12 a pressure control valve 24 is arranged, which is normally open and which is adapted to reduce the total exhaust gas stream to the exhaust gas aftertreatment system 14 and propels the exhaust gas recirculation through connecting duct 20 .
The reduced total exhaust gas flow through the pressure control valve 24 has two effects. Firstly, the amount of cooling air streaming through the exhaust gas aftertreatment system is reduced. Secondly, the reduced flow rate results in a pressure increase upstream of the pressure control valve 24 , which in turn is beneficial for propelling the recirculation of the exhaust gas through the connecting duct 20 to the induction duct 18 .
The inventive system as illustrated in the preferred embodiments of FIGS. 1 and 2 operates as follows: as soon as the accelerator pedal of the vehicle (for instance the gas pedal) is released and/or the fuel injection to the engine block 2 stops the gas recirculation valve 22 is controlled by a control 200 to open and the pressure control valve 24 is controlled to at least partly close so that part of the exhaust gas streams through connecting duct 20 into induction duct 18 . In contrast to known EGR engine systems, the inventive non-EGR engine does not comprise an exhaust gas cooler in the connecting duct 20 , so that hot exhaust gas is fed into induction duct 18 .
By feeding hot or uncooled exhaust gas into the induction duct 18 and therefore also into the engine block 2 , the air streaming through engine block 2 during idle or motoring engine operation modes is warmed up, which in turn reduces the cooling effect to the exhaust gas aftertreatment system 14 .
Additionally, as described above, mainly due to the (at least) partly closed pressure control valve 24 , the overall mass flow of exhaust gas to the exhaust gas aftertreatment system 4 is reduced or even (temporarily) stopped, which also decreases the air cooling effect of the exhaust gas aftertreatment system 14 during idle or motoring engine operation modes.
In order to not damage the engine block 2 by exhaust gases which are too hot, a temperature sensor 26 is arranged in the intake manifold 6 of the engine block 2 . The temperature sensor 26 also influences the control of the pressure control valve 24 so that the pressure control valve 24 opens more, if the temperature in the intake manifold is above a predetermined temperature range. In this case, the part of the exhaust gas streaming to the exhaust gas aftertreatment system 14 is increased and less amounts of hot exhaust gas is recirculated. This maximum temperature of the engine 1 is typically within a range between substantially 100° Celsius and substantially 150° Celsius, particularly within a range between substantially 110° Celsius and substantially 130° Celsius, preferably approximately around 120° Celsius.
As soon as the temperature control system detects that the gas temperature in the intake manifold 6 exceeds the predetermined maximum temperature, the amount of recirculated exhaust gas is either reduced or the recirculation of the exhaust gas is (temporarily) stopped completely. This can be achieved by increasing the opening degree of the pressure control valve 24 or by opening the pressure control valve 24 completely. Alternatively, the recirculation of the exhaust gas can also be stopped by controlling the gas recirculation valve 22 to close so that only fresh air (provided by the compressor 16 ) is led through engine block 2 . As soon as the temperature at the intake manifold 6 has decreased again and is below said predetermined maximum temperature, the valves 22 , 24 may return to their, e.g. previous, exhaust gas recirculation position, provided, of course, the engine 1 is still in the idle or motoring engine operation mode. In cases where a pressure control valve 24 is not provided valve 22 is to be used alone to control the recirculation of the exhaust gas.
As already mentioned in the discussion about the differences between the present invention and usual EGR-engines, a measurement or control of the mass flow of the exhaust gas into the induction duct 18 is not intended to be performed with the inventive method and system. This in turn means that the inventive system is not suited for a controlled NOx reduction as required from, or provided by, usual EGR engines. Moreover, recirculation of exhaust gases is only performed during idle or motoring engine operation modes so that an emission control would not take place during operation modes of the engine other than idle or motoring engine operation modes.
Also in contrast to the known temperature maintenance system, described in document WO 2007/032714, where the temperature in the exhaust gas aftertreatment system is maintained by significantly reducing the exhaust gas flow through the exhaust gas aftertreatment system, the inventive system controls the temperature in the exhaust gas aftertreatment system by inducing warm exhaust gas into the exhaust gas aftertreatment system during idle or motoring engine operation modes (only). Since the known EGR engines comprise an exhaust gas cooler, which is necessary for the NOx reduction provided by the EGR engine, the recirculated exhaust gas of the EGR engine cannot be used for providing a heated exhaust gas during idle or motoring engine operation modes.
An advantage of the inventive system and method is that existing non-EGR engines can be easily equipped or retrofitted with the inventive system. For that in the existing exhaust duct 12 of the engine 1 a connecting duct 20 is mounted as a branch for connecting the existing exhaust duct 12 with the existing induction duct 18 . This can be done, e.g. by welding. Additionally, a simple on/off valve 22 is arranged in the connection duct 20 , preferably near the outlet to the induction duct 18 , and a pressure control valve 24 is arranged in the exhaust gas duct 12 downstream the branching off of the connecting duct 20 .
It goes without saying that instead of two separate valves 22 , 24 a single valve providing the features of both the air recirculation valve 22 and the features of the pressure control valve 24 may be used.
Both valves can be controlled by a controller, preferably a central processing unit (CPU) or electronic control unit (ECU) already existing in the vehicle, which controls the valves 22 , 24 based on the temperature values (sensed by the preferably already existing temperature sensor 26 ) and the fuel injection. In case such a temperature sensor 26 is not provided, it is easily retrofitted. The controller can be e.g. an onboard computer system to which the valves are connected.
Since the valves are controlled by a controller, the inventive method is preferably stored as software code on a computer program product. This computer program product can also be part of the retrofitting kit.
It should be noted that the rather low number of necessary components and the simplicity of its operation make the inventive system more robust in its operation compared with (rather complex) EGR engines so that the probability that an operation failure occur in the inventive system is much lower, and the engine reliability is much higher, compared with the corresponding values of a typical EGR engine. Additionally, in a preferred embodiment, where the gas recirculation valve 22 is designed as a normally closed valve and/or the pressure control valve 24 is designed as a normally open valve, the engine 1 and the exhaust gas aftertreatment system 14 are still working, even if the control of the valves 22 , 24 fails. The engine 1 is only affected in so far that the exhaust gas recirculation during idle or motoring engine operation modes of the vehicle is not working any more.
Advantageously, by using the inventive method and system it is feasible to reach emission levels according to the EURO 6 standard also with non-EGR engines. This can e.g. be shown by running the standard emission test cycles, such as the world harmonized emission level test procedure which comprises two tests: The World Harmonized Transient Cycle (WHTC) test, which is run on cold and hot start conditions, and the World Harmonized Steady-State Cycle (WHSC) test. The WHTC test comprises a transient test of 1800 seconds duration with several motoring engine operation mode segments. Both test cycles are well known and described e.g. by the Commission of the European Community Enterprise Directorate General, in its pamphlet “Heavy duty engine validation of world harmonized duty cycle”, which can be downloaded from the internet at http://ec.europa.eu/enterprise/sectors/automotivelfiles/projects/report_whdc_en.pdf.
In FIG. 3 , the exhaust gas temperature measurement results during the WHTC test for hot start conditions are illustrated. Thereby two measurements—one according to the inventive method and one according to a standard method—are compared. In FIG. 3 , graph 30 shows the WHTC test using the inventive method and graph 32 shows the WHTC test running the engine in the standard way, i.e. without using the inventive method. On the x-axis the time is indicated (in units of seconds) and on the y-axis the temperature of the exhaust gas before the exhaust gas aftertreatment system (here: a SCR system) is indicated (in units of Celsius degrees).
As can be seen from FIG. 3 , the temperature differences of the exhaust gases measured for both methods before the SCR unit varies between approximately 10° Celsius and approximately 50° Celsius whereby the temperature values of the standard method (graph 32 ) are always lower than the temperature values of the inventive method (graph 30 ) (or equal at best). This measured temperature difference is sufficient for the inventive method to keep the SCR unit on operating temperatures so that, without any additional fuel introduction, emission levels according to EURO 6 standard can be reached even with standard EURO 4 and EURO 5 non-EGR engines.
As described above, the method and system provides a simple, cost-effective and robust possibility to provide a non-EGR engine having EURO 6 properties. This also means that well-established, well-known and proven non-EGR engines can be easily adapted to comply with the EURO 6 standard. Also, an easy retrofitting possibility for EURO 4 and EURO 5 vehicles is provided.
REFERENCE LIST
100 internal combustion engine system
1 internal combustion engine
2 engine block
4 piston cylinder
5 gas intake side of the engine block 2
6 intake manifold
7 exhaust gas outlet side of the engine block 2
8 exhaust manifold
10 turbine
12 exhaust gas duct
14 exhaust gas aftertreatment system
16 compressor
17 charge air cooler
18 induction duct
20 connecting duct
22 gas recirculation valve
4 pressure control valve
6 temperature sensor
30 graph indicating temperature vs time with inventive method
32 graph indicating temperature vs time without inventive method | A method and internal combustion engine system are provided for keeping an exhaust gas aftertreatment system within its working temperature range during an idle or motoring engine operation mode of an internal combustion engine. The method includes sensing the temperature of the gas at the gas intake side of the internal combustion engine and/or of the exhaust gas; determining whether or not the sensed temperature value is in a predetermined temperature interval or below a predetermined temperature threshold; determining whether the internal combustion engine is in idle or motoring engine operation mode; in case the internal combustion engine is determined to be in an idle or motoring engine operation mode, controlling the temperature of the gas at the gas intake side of the internal combustion engine to be within the predetermined temperature range or below the predetermined temperature threshold by recirculating exhaust gas through a connecting duct by controlling at least one valve. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a turbomolecular pump, and more particularly to a turbomolecular pump having improved stator blades.
2. Description of the Related Art
A turbomolecular pump is widely used as a vacuum apparatus for a semiconductor manufacturing equipment.
The turbomolecular pump has stator blades and rotor blades which are disposed on a stator portion and a rotor portion, respectively, in a multistage arrangement in an axial direction, and the rotor portion is rotated with a motor at high speed so that a vacuum (exhaust) action is performed.
FIGS. 11 ( a ) to 11 ( c ) show the structures of the rotor blade and the stator blade of the turbomolecular pump described above. FIG. 11 ( a ) shows an arrangement between the rotor blade and the stator blade, FIG. 11 ( b ) is a sectional perspective view showing a rotor that is cut along upper and lower planes of the rotor blade, and FIG. 11 ( c ) is a perspective view showing a part of the stator blade.
As shown in FIG. 11 ( a ), the turbomolecular pump is composed of a rotor 60 and a stator 70 that are fixedly disposed to rotor axes rotating at high speed.
The rotor 60 is composed of a rotor body 61 that accommodates a motor and magnetic bearings inside thereof, a rotor ring portion 64 arranged at an outer circumference of the rotor body 61 , and a plurality of blades 63 provided to the rotor ring portion 64 radially in a radial direction and tilted at a predetermined angle with respect to the rotational axis.
On the other hand, the stator 70 is composed of a spacer 71 and a stator blade 72 that are arranged between rotor blades 62 at the respective stages, while being supported its outer circumferential side between the spacers 71 and 71 .
The spacer 71 is a cylindrical shape having stepped portions, and the length of each stepped portion in an axial direction, located inside thereof, is varied in accordance with the intervals between the respective stages of the rotor blades 62 .
The stator blade 72 is composed of an outer ring portion 73 , part of outer circumferential portion of which is sandwiched by the spacers 71 in circumference direction, an inner ring portion 74 , and a plurality of blades 75 both ends of which are supported radially with a predetermined angle by the outer ring portion 73 and the inner ring portion 74 . The inner diameter of the inner ring portion 74 is formed to have a larger size than the outer diameter of the rotor body 61 so that an inner circumferential surface 77 of the inner ring portion 74 and an outer circumferential surface 65 of the rotor body 61 do not contact with each other.
In order to arrange the stator blade 72 between the rotor blades 62 at the respective stages, each stator blade 72 is divided into two parts in circumference. The stator blade 72 is made from a thin plate such as a stainless or aluminum thin plate that is divided into two. An outer portion having a semi-ring profile and portions for blades 75 of the stator blade 72 are cut out by means of etching from the thin plate, and the portions for blades 75 are folded by means of press machining to have a predetermined angle. Thus, the shape shown in FIG. 11 ( c ) is obtained.
In the thus formed turbomolecular pump, the rotor 60 is designed to be rotated with a motor at several tens of thousands r.p.m., so that an exhaust action is effected from the upstream side to the downstream side of FIG. 11 ( a )
In such conventional turbomolecular pump, since the support of the stator blades 72 by a spacer 71 is carried out with a cantilever configuration and the stator blades 72 are divided into two parts in circumference, large deflection would occur in the case that excess loads were applied to the stator blades 72 . In particular, in the stator blades 72 formed by means of press machining, since the thickness of the plate is thin, there have been cases where the open end on the center side was largely deflected at the portion divided into two parts.
For that reason, in the case where a large fluctuation occurred in a load of gas due to malfunction, etc. of valves attached to a vacuum chamber, the stator blades were caused to largely deflect with the result that, in the worst case, blades 75 of the stator blades were brought into contact with blades 63 of the rotor blades were damaged.
Further, in the case where such a structure was employed that a magnetic bearing was used for the rotor axis, there also occurred the case in which the stator blades 72 and the rotor blades 62 broken when brought into contact with each other due to vibration generated at the time of a trouble with the magnetic bearing device or of a touch-down of a touch down bearing upon a power failure.
SUMMARY OF THE INVENTION
The present invention has been made to solve the above-mentioned problems inherent in the conventional turbomolecular pump, and therefore has a primary object of the present invention to provide a turbomolecular pump with stator blades having a structure in which deflections are not relatively occurred.
Further, a secondary object of the present invention is to provide a turbomolecular pump with stator blades having a structure in which deflections are not relatively occurred.
Further, a secondary object of the present invention is to provide a turbomolecular pump with stator blades having a structure in which breakage of the stator blades are hardly occurred even if the stator blades are brought into contact with rotor blades due to deflections.
In order to attain the primary object of the present invention, according to the present invention, a reinforcement portion is arranged to the inner ring portion of each stator blade.
Further, according to the present invention, the reinforcement portion is constructed of a rib structure formed in the inner ring portion of the stator blade.
Still further, according to the present invention, said reinforcement portion is constructed of engagement means formed at end portions of the divided inner ring portion of the stator blade for engaging one end portion of the divided inner ring portion of said stator blade and the other end portion of the divided inner ring portion facing thereto.
In order to attain the secondary object of the present invention, according to the present invention, the blades of the stator blades at the respective stages comprise a multi-layer of plural pairs of blades overlapped with each other, and the phases of the divided positions at the respective layers are shifted with each other.
Further, according to the present invention, the blades of the rotor blades at the respective stages are provided to the rotor ring portion that is disposed to the rotor corresponding with the stage; and an outer diameter of the inner ring portion of the blades of the stator blades is smaller than an outer diameter of the rotor ring portion.
Further, according to the present invention, steps are formed at the outer ring portion so that the blades of the stator blades are allowed to contact with the outer ring portion.
BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawings:
FIG. 1 is a cross-sectional view showing the entire structure of a turbomolecular pump according to an embodiment of the present invention;
FIG. 2 shows the structure of a stator blade according to a first embodiment of the present invention, in which FIG. 2 ( a ) is a partially perspective view of the stator blade, and FIG. 2 ( b ) to 2 ( e ) show rib structure portions of the stator blade in which various shapes are employed;
FIG. 3 shows the structure of a stator blade according to a second embodiment of the present invention, in which FIG. 3 ( a ) is a perspective view showing both end portions of inner ring portions facing to each other; and FIG. 3 ( b ) is a cross-sectional view showing the engagement state of FIG. 3 ( a );
FIG. 4 shows the structure of the stator blade according to a first modification example of the second embodiment of the present invention, in which FIG. 4 ( a ) is a perspective view showing both end portions of the inner ring portions facing to each other; and FIG. 4 ( b ) is a cross-sectional view showing the engagement state of FIG. 4 ( a );
FIG. 5 is a perspective view showing both end portions of the inner ring portions of the stator blade facing to each other according to a second modification example of the second embodiment of the present invention;
FIG. 6 are conceptual views showing arrangements of a stator blade according to a third embodiment of the present invention, in which FIG. 6 ( a ) shows two pairs of the stator blades each consisting of two-divided stator blades to be overlapped so that coupling positions are shifted by 90° to each other, and FIGS. 6 ( b ) to 6 ( d ) show examples of the overlapping state of the pairs of stator blades;
FIG. 7 is a cross-sectional view showing a stator blade and a rotor blade of a turbomolecular pump according to a fourth embodiment of the present invention;
FIG. 8 is a cross-sectional view showing a stator blade and a rotor blade of a turbomolecular pump according to a first modification example of the fourth embodiment of the present invention;
FIG. 9 is a cross-sectional view showing a stator blade and a rotor blade of a turbomolecular pump according to a second modification example of the fourth embodiment of the present invention;
FIG. 10 is a cross-sectional view showing a stator blade and a rotor blade of a turbomolecular pump according to a third modification example of the fourth embodiment of the present invention; and
FIG. 11 shows the structures of a rotor blade and a stator blade of the conventional turbomolecular pump, in which FIG. 11 ( a ) shows an arrangement between the rotor blade and the stator blade, FIG. 11 ( b ) is a sectional perspective view showing a rotor that is cut along upper and lower planes of the rotor blade, and FIG. 11 ( c ) is a perspective view showing a part of the stator blade.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hereinafter, detailed descriptions will be made of the preferred embodiments of the present invention with reference to FIG. 1 to FIG. 10 .
(1) Outline of Embodiments
According to a first embodiment of the present invention, a rib structure is employed to an inner ring portion 74 of a stator blade 72 . As a specific rib structure, a variety of shapes such as a semicircular-shape, a semiellipse-shape, a U-shape, or reversed V-shape in cross-section in a radial direction may be employed. Those shapes may be formed by means of a press machining, or by attaching with welding, etc.
According to a second embodiment of the present invention, claws are formed by means of folding or welding, etc., at the connecting portions of two-divided stator blades 72 . As a result, rigidity is enhanced at the two-divided portion where the stator blades 72 are faced to each other, which hardly causes deflection of the blades.
According to a third embodiment of the present invention, the pair of the stator blades 72 each consisting of two-divided stator blades are overlapped to form a two-layer structure. Further, phases of the two-divided positions of the stator blades in the respective layers are shifted by 90° to each other,
According to a fourth embodiment of the present invention, there is employed a structure in which even in the case where the stator blades 72 and the rotor blades 62 are brought into contact with each other, blades 75 of the stator blades (hereinafter simply referred to as “blades S”) and blades 63 of the rotor blades (hereinafter simply referred to as “blades R”), which form planes of discontinuity and are the weakest portions in the structure, are prevented from contacting with each other. Specifically, the length of the blades S 75 in a radial direction is lengthened (extend) inwardly, so that in the case where the stator blades 72 are deflected, the top end portions 76 of the blades S 75 on the center side is brought into contact with a rotor ring portion 64 which is a plane of continuity of the rotor blades 62 , thereby preventing the blades S 75 from contacting with the blades R 63 . Further, an abutting portion (leg portion) is provided to the inner ring portion 74 of each stator blade 72 , with the result that even in the case where the stator blades 72 are largely deflected, the leg portion is allowed to contact with the rotor ring portion 64 . With taking a structure described above, it can be prevented both planes of discontinuity (blades S 75 and blades R 63 ) from directly contacting with each other, with the result that the stator blades 72 and the rotor blades 62 are hardly damaged.
(2) Details of Embodiments
Detailed descriptions of preferred embodiments of the present invention will be made hereinafter with reference to FIG. 1 to FIG. 10 . It is to be noted that, in the present embodiments, the same reference numerals are used to explain the same components in the conventional turbomolecular pump shown in FIG. 11, and the descriptions thereof are appropriately omitted. Only different portions between the conventional structure and the present embodiments are described.
FIG. 1 is a cross-sectional view showing the entire structure of a turbomolecular pump according to an embodiment of the present invention.
A turbomolecular pump 1 above is installed, for example, in semiconductor manufacturing equipment for exhausting a process gas from a chamber, etc. In this example, a flange 11 is formed at the top end portion of a casing 10 , and is allowed to join the semiconductor manufacturing equipment, etc., with bolts.
As shown in FIG. 1, the turbomolecular pump 1 is provided with a rotor shaft 18 that is substantially cylindrical and is arranged at the center portion of the casing 10 . Arranged to the outer periphery of the rotor shaft 18 is a rotor body 61 having a substantially inverted U-shaped in cross-section to be attached to the top portion of the rotor shaft 18 with bolts 19 . Around the outer periphery of the rotor body 61 , the rotor ring portions 64 are arranged in multistage manner, and the rotor blades 62 are arranged to the respective rotor ring portions 64 . The rotor blades 62 at the respective stages include a plurality of the blades 63 with an open end.
Further, the turbomolecular pump 1 is provided with the rotor 60 and the stator 70 .
The stator 70 is constructed of the plurality of stator blades 72 and the cylindrical spacers 71 having stepped portions. The stator blades at the respective stages are divided into two as described later, and are inserted between the rotor blades 62 at the respective stages outwardly to be assembled. The stator blades 72 at the respective stages are sandwiched in a circumferential direction at the outer ring portion 73 between the spacers 71 and 71 , respectively, thereby being retained between the rotor blades 62 .
The stator 70 is fixedly disposed to the inner periphery of the casing 10 .
The rotor blades 62 and the stator blades 72 according to the present embodiment serve as an exhaust stage, an intermediate stage, and a compression stage from the upstream thereof. It should be noted that the present invention is not limited to a three-stage structure consisting of the exhaust, intermediate, and compression stages, and a variety of structures may be employed such as a two-stage structure consisting of the exhaust stage and the compression stage, a two-stage structure in which each stage plays another function, and a structure with no limitation in the function of each stage.
The turbomolecular pump 1 further includes a magnetic bearing 20 for supporting the rotor shaft 18 with magnetic force, and a motor 30 for generating torque to the rotor shaft 18 .
The magnetic bearing 20 includes radial electromagnets 21 and 24 for generating a magnetic force in a radial direction to the rotor shaft 18 , radial sensors 22 and 26 for detecting the position of the rotor shaft 18 in a radial direction, axial electromagnets 32 and 34 for generating a magnetic force in an axial direction to the rotor shaft 18 , a metal disk 31 to which force generated by the axial electromagnets 32 and 34 is acted, and an axial sensor 36 for detecting the position of the rotor shaft 18 in an axial direction.
The radial electromagnet 21 is composed of two pairs of electromagnets that are disposed so as to be orthogonal with each other. The respective pairs of electromagnets are disposed at an upper position than the motor 30 of the rotor shaft 18 , while sandwiching the rotor shaft 18 therebetween.
Provided between the radial electromagnet 21 and the motor 30 are two pairs of radial sensors 22 facing with each other and sandwiching the rotor shaft 18 therebetween, and being adjacent to the radial electromagnet 21 side. The two pairs of radial sensors 22 are disposed so as to cross at right angles with each other in correspondent with two pairs of radial electromagnets 21 .
Furthermore, two pairs of electromagnets 24 are similarly disposed at a lower position than the motor 30 of the rotor shaft 18 so as to be orthogonal with each other.
Between the radial electromagnet 24 and the motor 30 , two pairs of radial sensors 26 are similarly provided so as to be adjacent to the radial electromagnet 24 .
By supplying excitation current to these radial electromagnets 21 and 24 , the rotor shaft 18 is magnetically levitated. This excitation current is controlled bin correspondence with the position detection signals from the radial sensors 22 and 26 upon the magnetic levitation. As a result, the rotor shaft 18 is secured at the prescribed position in the radial direction.
Onto the lower portion of the rotor shaft 18 , a discoid metal disk 31 formed of the magnetic substance is fixed. Each one pair of axial electromagnets 32 and 34 facing with each other are disposed while sandwiching this metal disk 31 therebetween. Further, the axial sensors 36 are disposed facing with each other at the lower end portion of the rotor shaft 18 .
The excitation current of the axial electromagnets 32 and 34 is controlled in correspondent with the position detection signal from the axial sensor 36 . As a result, the rotor shaft 18 is secured at the prescribed position in the axial direction.
The magnetic bearing 20 includes a magnetic bearing controlling section disposed within a controller 45 for magnetically levitating the rotor shaft 18 by feedback controlling the excitation current of the radial electromagnets 21 and 24 and the axial electromagnets 32 and 34 , respectively, on the basis of the detection signals of these radial sensors 22 and 26 and the axial sensor 36 .
The touch down bearings 38 and 39 are disposed at the upper and lower sides of the rotor shaft 18 .
In general, the rotor portion consisting of the rotor shaft 18 and respective portions attached thereto is axially supported in a non-contact state by the magnetic bearing 20 during its rotation with the motor 30 . The touch down bearings 38 and 39 play a part for protecting the entire device by axially supporting the rotor portion in place of the magnetic bearing 20 when the touch down occurs.
Therefore, the touch down bearings 38 and 39 are arranged so that the inner race of the bearings 38 and 39 are in the non-contact state against the rotor shaft 18 .
The motor 30 is disposed between the radial sensor 22 and the radial sensor 26 inside the casing 10 substantially at the center position of the rotor shaft 18 in the axial direction. The rotor shaft 18 , the rotor 60 and the rotor blades 62 fixed thereto are allowed to rotate by applying a current to the motor 30 .
An exhaust port 52 for exhausting the processed gas or the like from the semiconductor manufacturing equipment is disposed at the lower portion of the casing 10 of the turbomolecular pump 1 .
Also, the turbomolecular pump is connected to the controller 45 through the connector 44 and the cable.
FIGS. 2 ( a ) to 2 ( e ) show the structure of the stator blade 72 according to the first embodiment of the present invention.
As shown in FIG. 2 ( a ), the stator blade 72 is constructed of an outer ring portion 73 part of the outer circumference side of which is sandwiched in the circumferential direction by the spacers 71 , the inner ring portion 74 , and a plurality of blades 75 both ends of which are radially supported with a predetermined angle by the outer ring portion 73 and the inner ring portion 74 . The inner diameter of the inner ring portion 74 is formed larger than the outer diameter of the rotor body 61 , so that the inner circumferential plane 77 of the inner ring portion 74 , and the outer circumferential plane 65 of the rotor body 61 do not contact with each other (refer to FIG. 11 ( a )).
A rib structure portion 80 that functions as the reinforcement member is formed at the inner ring portion 74 . This rib structure portion 80 is formed in the circumferential direction from an end face 78 of the two-divided inner ring portion 74 to the end face 78 on the other side. The rigidity with respect to the deflection of the inner ring portion 74 can be enhanced by the provision of the rib structure portion 80 .
The stator blade 72 is made from a thin plate such as a stainless or aluminum thin plate. An outer portion having a semi-ring profile and portions for blades 75 of the stator blade 72 are cut out by means of etching from the thin plate, and the portions for blades 75 are folded by means of press machining to have a predetermined angle. Then, the rib structure portion 80 is press-machined, and to thereby form the stator blades 72 shown in FIG. 2 ( a ) is obtained.
As the specific shape (sectional shape in a radial direction) of the rib structure portion 80 , though it is optional, it is possible to employ a variety of shapes such as a semicircular-shape with a radius R (FIG. 2 ( b )), a semiellipse-shape having a plane portion with the length of b in the radial direction and being chamfered with the radius R (FIG. 2 ( c )), a U-shape with the length of b and the height of h in the radial direction (FIG. 2 ( d )), or a reversed V-shape with the height of h and the width of b (FIG. 2 ( e )) and the like.
Further, in FIGS. 2 ( b ) to 2 ( e ), as the rib structure portion 80 , the shapes that are press-machined so as to protrude in the upward direction of the drawings are shown. However, the press machining may be conducted so that the rib structure portion protrudes in the downward direction of the drawings.
In the stator blades 72 of the first embodiment of the present invention, the description was made of the case in which in order to decrease the amount of deflection of the blades in an axial direction, the rib structure portion 80 was formed by press machining as reinforcement portion in the inner ring portion 74 . However, other structure may be employed as the reinforcement portion.
For example, the reinforcement member may be a separate structure which can be fixed to the inner ring portion 74 in a circumferential direction by welding or the like from one end face 78 of the two-divided inner ring portion 74 to the end face 78 on the other side. As the shape of the reinforcement member in cross-section in a direction that is orthogonal to the longitudinal direction of the reinforcement member, a variety of shapes such as square, triangle, semicircular, or semiellipse may be employed.
FIGS. 3 ( a ) and 3 ( b ) shows the structure of the stator blade 72 according to a second embodiment of the present invention, in which both end portions of inner ring portions facing to each other are shown.
In FIGS. 3 ( a ) and 3 ( b ), one end out of a pair of two-divided inner ring portions 74 is denoted by reference symbol 74 a, and the other end is denoted by reference symbol 74 b. Further, if a right side end portion of the both inner ring portions 74 a and 74 b viewed from the rotor axis 18 side is assumed as one end portion, and a left side end portion is assumed as the other end portion, the shapes of the one end portion and the other end portion of the inner ring portion 74 a are formed identical to that of the inner ring portion 74 b. FIG. 3 ( a ) shows the one end portion of the inner ring portion 74 a and the other end portion of the inner ring portion 74 b.
Note that the relationship between the one end portion and the other end portion of the inner ring portions 74 a and 74 b is the same as in modification examples shown in FIGS. 4 ( a ) and 4 ( b ) and FIG. 5 .
As shown in FIGS. 3 ( a ) and 3 ( b ), in order to enhance the rigidity of the two-divided stator blades 72 , reinforcing means comprised of engagement claws 81 a and 81 b are provided as engagement members to one of the two-divided end faces 78 a of the inner ring portion 74 . Also, provided to the two-divided end face 78 b on the other side of the inner ring portion 74 is another engagement member in the form of an engagement claw 81 c.
Although the dimensions of widths b 1 , b 2 , and b 3 of the respective engagement claws 81 a, 81 b, and 81 c in a radial direction are optional, the total value of b 1 +b 2 +b 3 must be equal to or smaller than the width of the inner ring portion 74 in the radial direction. Also, the distance between the engagement claw 81 a and the engagement claw 81 b is required to be equal or larger than the width b 2 of the engagement claw 81 c. Furthermore, the lengths 11 of the engagement claws 81 a and 81 b and the length 12 of the engagement claw 81 c are also optional. The above-mentioned relationships are the same as in the respective modification examples shown in FIGS. 4 ( a ) and 4 ( b ) and FIG. 5 .
As shown in FIG. 3 ( a ), in the engagement claws 81 a and 81 b, the joining portion to the inner ring portion 74 a are curved upwardly as much of the thickness of the inner ring portion 74 . Similarly, in the engagement claw 81 c, the joining portion to the inner ring portion 74 b is curved upwardly as much of the thickness of the inner ring portion 74 .
The engagement claws 81 a , 81 b, and 81 c in accordance with the present embodiment are machined by folding the engagement claw portions integrally formed. However, the curved engagement claws 81 may be separate members which are fixed to the inner ring portion 74 by welding. It is to be noted that in the case of welding or the like of the engagement claws, it may take a structure in which the engagement claws 81 are overlapped on the inner ring portion 74 and then welded. The methods of provision of the engagement claws described above are the same as in the modification examples shown in FIGS. 4 ( a ) and 4 ( b ) and FIG. 5 .
FIG. 3 ( b ) shows an engagement state of the inner ring portions 74 a and 74 b when a pair of the two-divided stator blades 72 is coupled.
As shown in the figure, the pair of the two-divided inner ring portions 74 a and 74 b are engaged with the engagement claws 81 , and the rigidity against the deflection from the upper side to the down side of the drawing is improved.
It is to be noted that if it is designed such that the engagement claws are disposed to the lower side of the inner ring portion 74 , the rigidity against the deflection from the lower side to the upper side of the drawing may also be improved.
FIG. 4 shows the abutting portion of the inner ring portions according to a first modification example of the second embodiment of the present invention.
In this modification example, as shown in FIG. 4 ( a ), engagement claws 82 a and 82 c curved downwardly at the joining portion as much of the thickness of the inner ring portion 74 are provided to one end portion of the inner ring portion 74 a, and an engagement claw 82 b curved upwardly at the joining portion as much of the thickness of the inner ring portion 74 is provided therebetween.
Further, the other end of the inner ring portion 74 b is a flat plate with no engagement claw, and as shown in FIG. 4 ( b ), the engagement claws 82 a and 82 c are engaged with the lower side of the inner ring portion 74 b and the engagement claw 82 b is engaged with the upper side thereof.
According to the first modification example, one end portion of the pair of inner ring portions 74 a and 74 b are engaged with both upper and lower surfaces of the other end portion thereof through the engagement claws 82 a, 82 b, and 82 c. As a result, the rigidity against the deflections from both the upper side and the lower side of the drawing may be improved.
FIG. 5 shows the abutting portion of the inner ring portions according to a second modification example of the second embodiment of the present invention.
In this modification example, as shown in FIG. 5, a sandwiching claw 83 a is provided to one end portion of the inner ring portion 74 a, and an engagement claw 83 b curved upwardly at the joining portion as much of the thickness of the inner ring portion 74 is provided to the outer end of the inner ring portion 74 b.
The sandwiching claw 83 a is formed of a member having an L-shape in cross-section, and is configured such that an open end side of a lower horizontal bar portion of the L is attached to a face 77 a facing to the rotor of inner ring portion 74 a, and the lower horizontal bar portion is extended upwardly in an axial direction as much of the thickness of the inner ring portion 74 , and in addition, a vertical bar portion of the L is extended in a radial direction.
In this modification example, the engagement claw 83 b is sandwiched by the inner ring portion 74 a and the sandwiching claw 83 a. As a result, the rigidity against the deflections from both the upper side and the lower side of the drawing may be improved.
The sandwiching claw 83 a is formed by cutting out a rectangular portion integrally with the inner ring portion 74 a, and folding this rectangular portion by means of press machining in an axial direction and in an opposite direction to the axial center direction.
It should be noted that the shape of the sandwiching claw 83 a in cross-section is not limited to L-shape, and a U-shape in cross-section may be employed. The sandwiching claw in this case has such a profile that the length 11 of the L-shape vertical bar portion of the sandwiching claw 83 a, shown in FIG. 5, is longer than the width b 2 of the engagement claw 83 b, and the tip end thereof is further folded toward the inner ring portion 74 a.
In addition, the sandwiching claw 83 a may be formed separately from the inner ring portion 74 a to fixed to the inner ring portion 74 by welding. In the case where the sandwiching claw is to be welded to the inner ring portion 74 a by welding, the sandwiching claw may be welded not only on the face 77 a facing to the rotor but also on the surface facing to the rotor blades 62 . In this case, depending upon the welding position of the sandwiching claw 82 , the position at which the engagement claw 83 b is arranged, may be adjusted. In this way, provision of the sandwiching claw 83 on the surface facing to the rotor blades may prevent the interval between the outer periphery of the rotor body 61 from narrowing.
FIG. 6 is a conceptual view showing arrangements of a stator blade 72 according to a third embodiment of the present invention.
In the third embodiment, two-divided stator blades 72 a and 72 b and two-divided stator blades 72 c and 72 d are overlapped to constituted the stator blades 72 at the respective stages.
As shown in FIG. 6 ( a ), the phase of the two-divided position of a pair of the stator blades 72 a and 72 b and that of the other pair of the stator blades 72 c and 72 d are shifted by 90° to each other to be then overlapped. It should be noted that if the phases of the divided positions of the respective pairs do not coincide with each other, the shift thereof is not limited to 90°, for example, arbitrary angle such as 30°, 45°, or 60° may be shifted.
FIGS. 6 ( b ) to 6 ( d ) show examples of the overlapping methods of the two pairs of the stator blades 72 according to the third embodiment of the present invention.
As a first method, as shown in FIG. 6 ( b ), there is employed a case in which the upper side stator blades 72 a and 72 b and the lower side stator blades 72 c and 72 d are abutted at the outer ring portions 73 and the inner ring portions 74 to each other. As a result, the blades 75 a and 75 and the blades 75 c and 75 d are disposed at the upper and lower sides, respectively.
As a second method, as shown in FIG. 6 ( c ), it is configured such that the upper stator blades 72 a and 72 b and the lower stator blades 75 a and 75 b are disposed with predetermined intervals so that the blades 75 a and 75 b and the blades 75 c and 75 d are opposedly disposed to each other. It is to be noted that the given interval between the upper and lower stator blades 72 is set on the basis of a spacer disposed between the outer ring portion 73 and the inner ring portion 74 of the stator blades 72 .
As a third method, as shown in FIG. 6 ( d ), the conventional stator blades shown in FIG. 11 ( a ) are used for the upper side stator blades 72 a and 72 b. Note that the lower stator blades 72 c and 72 d have no blades 75 , and ventilation holes are formed by punching out the portions for the blades 75 .
It should be noted that, in the first and second methods shown in FIGS. 6 ( b ) and 6 ( c ), the blades 75 a, 75 b, 75 c and 75 d having a length of a half of the conventional ones are used so that the length covering the upper and lower layers is identical with that of the conventional ones.
As described above, according to the first to third embodiments and the modification examples thereof, the rigidity of the stator blades can be improved. For that reason, the distance between the stator blades 72 and the rotor blades 62 can be made shorter than the conventional ones, thereby being capable of enhancing the down-sizing of the apparatus and the exhaust performances.
FIG. 7 is a cross-sectional view showing the stator blades and the rotor blades of a turbomolecular pump according to a fourth embodiment of the present invention.
In this embodiment, there is employed a structure in which the blades S 75 and the blades 63 that are planes of discontinuity and are the weakest portions in structure, are prevented from contacting with each other, thereby preventing damage to the the stator blades 72 and the rotor blades 62 .
Specifically, the length of the blades S 75 in a radial direction extends in an axial center direction so that the top end portions 76 of the blades S 75 on the center side are arranged between the rotor ring portions 64 and 64 .
As described above, with the top end portions 76 of the blades S 75 on the center side being arranged between the rotor ring portions 64 and 64 , even if the stator blades 72 are largely deflected, the top end portions 76 of the blades S 75 on the center side are brought into contact with a rotor ring portion 64 which is a plane of continuity of the rotor blades 62 , thereby preventing damage to the blades S 75 .
FIG. 8 is a cross-sectional view showing a stator blade and a rotor blade of a turbomolecular pump according to a first modification example of the fourth embodiment of the present invention.
In this modification example, an abutting portion 85 is provided to the inner ring portion 74 of each stator blade 72 , thereby preventing the blade S 75 and blades R 63 from contacting with each other.
As shown in FIG. 8, the abutting portion 85 has a substantially U-shape in cross-section, and has such a structure that the abutting portion is folded back in an opposite direction to the axial center.
Further, the abutting portion 85 is configured to satisfy the relation of δ1≦δ2≦x, where the distance between the upper most top end face 85 a in the axial direction of the abutting portion 85 and its upper facing rotor ring portion 64 is prescribed as “δ2,” and the distance between the top end face of the blades S 75 and the lower end face of the blade R 63 is prescribed as “δ1.”
In this case, “X” means the distance between the upper most top end face 85 a in the axial direction of the abutting portion 85 and it supper facing rotor ring portion 64 in the case where the upper most top end face 85 a in the axial direction of the abutting portion 85 and the top end face 76 on the center side of the blades S 75 are simultaneously brought into contact with the rotor blades 62 , when the stator blades were deflected.
In the first modification example of the fourth embodiment of the present invention, as shown in FIG. 8, the abutting portion 85 is folded back against the axial direction to have a U-shape in cross-section. As a result, the abutting portion 85 functions as a spring, thereby being capable of absorbing the impact at the time when the upper most top end face 85 is brought into contact with the rotor ring portion 64 .
FIG. 9 is a cross-sectional view showing a stator blade and a rotor blade of a turbomolecular pump according to a second modification example of the fourth embodiment of the present invention.
In this modification example, similar to the first modification example, the abutting portion that abuts against the rotor ring portion 64 is provided to the inner ring portion 74 of the stator blades 72 . However, in the second modification example, an abutting portion 86 having a rectangular shape is provided to the inner ring portion 74 of the stator blades 72 .
The condition relating to the distance δ2 between the top end face 86 a of the abutting portion 86 and its upper facing rotor ring portion 64 is similar to that of the first modification example of the fourth embodiment of the present invention.
FIG. 10 is a cross-sectional view showing a stator blade and a rotor blade of a turbomolecular pump according to a third modification example of the fourth embodiment of the present invention.
In this third modification example, the abutting portion 86 according to the second modification example of the fourth embodiment of the present invention is disposed to the inner ring portion 74 . Also, the distance between the end portion of the blades S 75 and the spacers 71 side in a radial direction and the spacers 71 is configured to be wider than the distance between the distal end of the blades R 63 a and 63 b and the spacers 71 so that the length of blades S 75 in a radial direction become shorter than the length of the blades R 63 a and 63 b.
Further, the outer ring portion 73 of the stator blade 72 is configured to have a stepped portion between a first ring portion 87 a on the side being sandwiched by the spacers 71 and a second ring portion 87 b for supporting blades S 75 . The stepped portion is provided to the whole outer ring portion 73 of the stator blade 72 in a circumferential direction thereof. The length of the first ring portion 87 a in the axial direction is set to the length so that the top face thereof is positioned between the blades R 63 a and 63 b.
It should be noted that since the position of the first ring portion 87 a held by the spacers 71 in the axial direction is moved to the upper than the conventional ones, the length of the spacers 71 is adjusted based on the shape of the outer ring portion 73 of the blade S 75 .
The outer ring portion 73 is configured so as to satisfy the relation of 0<δ3<P, where the distance between the top face of the first ring portion 87 a and the blades R 63 a is prescribed as s 3 . In this case, value “P” means the distance between the first ring portion 87 a and the blades R 63 a in the case where blades R 63 a are brought into contact with the first ring portion 87 a and the blades S 75 , simultaneously, when the rotor blades 62 were deflected downwardly.
According to the thus configured third modification example of the fourth embodiment of the present invention, when the stator blades 72 were deflected, the abutting portion 86 is brought into contact with the rotor ring portion 64 , thereby preventing the damage of the blades S 75 .
On the other hand, in the case where the rotor blades 62 are largely downwardly deflected, the blades R 63 a positioned at the upper portion of the outer ring portion 73 of stator blades 72 are brought into contact with the first ring portion 87 a of the outer ring portion 73 . In the case where the blades R 63 a and 63 b are largely upwardly deflected, the blades R 63 b are brought into contact with the second ring portion 87 b. Since the first and second ring portions 87 a and 87 b form the plane of continuity in a circumferential direction, even if the blades R 63 are brought into contact therewith, the damage of the blades R 63 a and 63 b can be prevented.
It should be noted that the abutting portions 85 and 86 , according to the first, second, and third modification examples of the fourth embodiment of the present invention, are provided to the whole inner ring portion 74 in a circumferential direction from one end portion to the other end portion.
Alternatively, the abutting portion 85 or 86 may be provided to both one end portion and the other end portion of the inner ring portion 74 . In the latter case, at least one abutting portion 85 or 86 may further be provided between one end portion and the other end portion.
As described above, descriptions have been made of the respective embodiments and their modification examples. However, the present invention is not limited thereto, various modifications may be adopted if such modifications fall within the scope of claim described in each claim.
For example, among the respective stator blades 72 described in the first, second and third embodiments of the present invention, the stator blades may be configured by a combination at least two structures. For example, the combination of the first and second embodiments allow the provisions of the rib structure (enhancement portion (reinforcement member) as well as the engagement claws for engaging one end with the other end, to the inner ring portion 74 of the stator blades 72 .
Further, as another modification example of the second embodiment of the present invention, such a configuration may be employed in which a concave portion in a radial direction is formed at one end face 78 a of the two-divided inner ring portion 74 a, and a convex portion to be fitted to the concave portion is provide to the other end face 78 b of the two divided inner ring portion 74 b.
As described above, according to the first to third embodiments of the present invention, even if a large fluctuation occurred in a load of gas, since the rigidity of the stator blades 72 is improved, the deflection of the stator blades 72 is restrained. As a result, the stator blades 72 are hardly brought into contact with the rotor blades 62 .
Furthermore, according to the fourth embodiment of the present invention, even if the stator blades 72 and the rotor blades 62 are brought into contact with each other, before the portions that are weak in structure (the blades S 75 and the blades 63 ) are brought into contact with each other, other portions are allowed to contact with each other, thereby being capable of preventing the fatal damages of the stator blades 72 and the rotor blades 62 .
Even in the case where the magnetic bearing is subjected to touch down against the touch down bearing, if the structures according to the first to third embodiments of the present invention is employed, the deflection the stator blades can be prevented. If the structure according to the fourth embodiment of the present invention is used, contact between the blades can also be prevented.
As described above, according to the present invention, it is possible to provide the turbomolecular pump with stator blades having a structure in which deflections are not relatively occurred. The stator blades are hardly deflected, thereby being capable of narrowing the distance between the stator blades and the rotor blade. As a result, the downsizing of the turbomolecular pump may be realized and exhaust performances may be improved.
Further, according to the present invention, it is possible to provide a turbomolecular pump with stator blades having a structure in which even if the deflection of the stator blades occurred, since the contacts between the blades S and the blades R can be prevented, breakage of the stator blades hardly occurrs. | A turbomolecular pump comprises a casing, a rotor having a rotor blades arranged in multiple stages in the casing axially thereof, and a stator having stator blades arranged in multiple stages and alternately located between the rotor blades. Each of the stator blades has an inner ring portion, an outer ring portion spaced-apart from the inner ring portion, and blades connected between the inner and outer ring portions along a circumferential direction thereof. Each of the blades has a first end connected to an outer peripheral edge of the inner ring portion and a second end opposite the first end connected to an inner peripheral edge of the outer ring portion. A reinforcement member is disposed on the inner ring portion of each of the stator blades along the entire circumference of the inner ring portion for reinforcing the stator blade. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a technique for starting PDA (Personal Digital Assistant) OS (Operating System) and its utilities in a portable PC (Personal Computer), such as a notebook PC or equivalent electronic device. More specifically, in a notebook PC in which multiple PDA OS's are installed, a method and system is proposed to provide an OS menu for the user to select one of the PDA OS's and to start the PDA OS (including the OS's of hand held PC's, pocket PC's and other equivalent small electronic devices).
2. Related Art
With the increase in computer popularity, people often need to use computers to solve problems either at work or at home. In general, two major methods of obtaining information are: (1) from books, newspapers, journals, CD-ROM's, etc; and (2) from the network. However, both of these methods have drawbacks. The information obtained using the first method will become outdated as time progresses. Rapid exchange of information greatly shortens the life cycle of the information. However, such information recorded in media like books cannot be easily updated. The information obtained using the second method, however, continuously changes along with the development of the world, also resulting in some troubles for users. One can see the problems from the following points:
1. Existing personal computer OS's (Operating Systems), such as Windows 98, Windows 2000, Windows XP, Linux, and so on, are complicated despite (or because of) their powerful functions and designs. Moreover, the user operation designs are not intuitive and simple enough. This situation scares people without any computer background because of the obstacles they meet while using these systems. 2. Users who do not understand the network structure do not know where to start their searches. In this case, the user often chooses to use a familiar OS or to install several different OS's in the computer hardware platform. This type of systems is called a dual-OS or a multi-OS. However, this method cannot solve the above problems because a utility is needed to switch between the OS's. 3. PDA's are becoming more popular nowadays. They have properties complementary to the desktop Windows OS, e.g. smaller volume, faster power on, more compact functions, and more convenient to use. Therefore, a method of supporting multiple PDA systems on a notebook PC is an important subject being studiedhe user is then able to enjoy the functions of different PDA systems on the same notebook PC.
SUMMARY OF THE INVENTION
An object of the invention is to provide a technique that can arbitrarily assign and start an OS in a notebook PC on which multiple PDA OS's and the normal OS (such as the Windows OS) are installed.
The disclosed method mainly applies to a notebook PC on which multiple OS's are installed. These OS's include at least one PDA OS (including the OS's of hand held PC's, pocket PC's and other small electronic devices, all of which are hereinafter referred as PDA) and a basic OS. By modifying the BIOS (Basic Input Output System) booting procedure, the OS information installed in the notebook PC is read from the MBR (Master Boot Record) immediately after the power is turned on. The multiple OS information installed in the notebook PC is obtained and listed in a menu on a display. The user can then directly start any OS through this menu.
The disclosed system is mainly built upon a notebook PC on which multiple OS's are installed. Aside from the basic OS (such as the Windows OS) pre-loaded into the notebook PC, the starting procedure of the basic OS, and the power on button for starting the notebook PC, the system further includes:
a PDA OS stored in a storage device of the notebook PC; a PDA starting procedure, which is pre-loaded into the BIOS of the notebook PC for starting the PDA OS and opening PDA utilities; an OS detecting procedure, which is pre-loaded into the BIOS of the notebook PC for the notebook PC to detect installed multiple OS's and to list the OS's in a menu on a display, whereby the user can select and start any one of the OS's using input devices; and a quick hardware diagnostic procedure, which is pre-loaded into the BIOS of the notebook PC to perform hardware diagnoses for the input devices that support such menu manipulations, skipping complicated hardware diagnosis steps in the normal starting procedure of the notebook PC, so as to accelerate the speed of starting the notebook PC.
Further scope of the applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein:
FIG. 1 is a flowchart showing the steps for implementing the invention;
FIG. 2 shows a hardware structure of the invention;
FIG. 3 shows a system structure of the invention;
FIG. 4 is a flowchart showing the operation procedure of the BIOS chip 11 after the power is turned on;
FIG. 5 is a flowchart showing the steps of starting the basic OS and its utilities;
FIG. 6 is a flowchart showing the steps of starting the PDA OS and its utilities;
FIG. 7 is a flowchart of another embodiment showing the steps of staring a PDA OS and its utilities using a hot key; and
FIG. 8 is the hardware structure of another embodiment, showing the structure of adding a PDA hot key.
DETAILED DESCRIPTION OF THE INVENTION
With reference to FIG. 1 , the disclosed method mainly applies to a notebook PC on which multiple OS's are installed, including at least one PDA OS and a basic OS pre-loaded into the notebook PC (such as the Windows OS). The following steps are taken to achieve the goal of starting an OS from a menu with multiple OS's:
1. The BIOS contents of the notebook PC, particularly the contents in the booting block, are modified to implement the following functions: (1) skipping some hardware device diagnosis steps in order to speed up the notebook PC system power on; and (2) detecting multiple OS's installed on the notebook PC. 2. The detected multiple OS's are listed in a menu on an output device such as a display or other equivalent device. 3. The system obtains information about the OS selected by the user from the menu (e.g. the PDA OS). The user can assign any OS in the menu to be started using input devices such as a mouse, keyboard, touch-control monitor, or other equivalent device. 4. The OS selected by the user is then started.
As shown in FIG. 2 , the hardware structure using the disclosed technique is mainly based upon the basic hardware devices of current notebook PC's. The hardware structure includes at least: a CPU (Central Processing Unit) 10 , a BIOS (Basic Input Output System) chip 11 , main memory 12 , a storage device 13 (e.g. HD, CD-ROM, memory or other recording media), a power on button 20 , an output device 14 (e.g. display, touch-control monitor or other equivalent device), and an input device 15 (e.g. mouse, keyboard, touch-control monitor or other equivalent device).
With reference to FIG. 3 , the system of the invention includes: a basic OS (e.g. Windows OS) 31 pre-loaded into the notebook PC, a basic OS booting procedure 32 , utilities 33 for the basic OS 31 , and a drivers 34 for the basic OS 31 . In addition, the system also includes:
a PDA OS 40 stored in the storage device 13 of the notebook PC 13 ; utilities 41 for the PDA OS; a PDA booting procedure 42 pre-loaded into the BIOS chip 11 of the notebook PC for starting the PDA OS 40 and its utilities 41 ; drivers 43 for the PDA OS 41 ; and a booting procedure module 44 pre-loaded into the BIOS chip 11 of the notebook PC, which includes: a quick hardware diagnostic procedure 441 to speed up the notebook PC power on by skipping some hardware device diagnostic steps, and an OS detecting procedure 442 for detecting multiple OS's already installed in the notebook PC (e.g. the pre-loaded Windows OS 31 and the PDA OS 40 ) and showing them in a menu on the output device 14 .
The basic OS-related software, including the utilities 33 and the drivers 34 , and the PDA OS-related software, including the utilities 43 and the drivers 44 , are separately stored in the storage device 13 of the notebook PC. It is preferable to store them in different HD partitions 131 and 132 of the HD. The PDA booting procedure 42 and the booting procedure 32 of the basic OS 31 are stored together in the BIOS chip 11 of the notebook PC.
FIG. 4 shows a notebook PC in which the disclosed techniques are implemented. After the power is turned on, the operations performed by the BIOS chip 11 includes the steps of:
A. running partial hardware diagnosis, which, through the quick hardware diagnostic procedure, only performs hardware diagnosis for a few input devices 15 that support menu operations (e.g. mouse, keyboard, touch-control monitor, etc) in order to accelerate the power on speed of the notebook PC by skipping complicated hardware diagnosis in normal booting procedures of the notebook PC; B. detecting OS's already installed in the notebook PC (e.g. the pre-loaded Windows OS 31 and the PDA OS 40 ) through the OS detecting procedure 442 and listing them in a menu on an output device 14 ; C. obtaining the selection information about the OS (e.g. a PDA OS) selected by the user from the menu; and D. starting the OS selected by the user.
The OS detecting procedure 442 obtains information of all the OS's installed in the storage device 13 of the notebook PC by reading the OS partition messages stored in the MBR (Master Boot Record).
According to the selection result in step C, the BIOS chip 11 runs the PDA booting procedure 42 or the basic OS booting procedure 32 to start the PDA OS 40 and its utilities 41 or the basic OS 31 and its utilities 33 , depending on whether the user selects the PDA OS or the basic OS 31 from the menu.
The booting procedure 32 of the basic OS 31 is executed differently from the booting procedure 42 of the PDA OS 40 . As shown in FIG. 5 , the booting procedure of the basic OS 31 includes the steps of:
(a) performing a POST (Power On Self Test) procedure; (b) loading the pre-loaded basic OS 31 into the main memory 12 ; and (c) starting the basic OS 31 and running its utilities 33 .
As shown in FIG. 6 , the booting procedure of the PDA OS includes the steps of:
(A) loading the pre-loaded PDA OS 40 into the main memory 12 ; and (B) starting the PDA OS 40 and running its utilities 41 .
From the above description, one sees that complicated hardware diagnostic steps are performed at the beginning of starting the basic OS 31 . This is the so-called POST. It mainly tests the size of the memory, the defects in the memory, the keyboard functions, the display interface card type, the types and models of the hard drive and floppy disk drive, and the functions of the interrupt controller and timer. If there is any conflict between the interface card settings and the host, a warning message will be displayed or the system cannot be loaded. For printers, the tests include whether the print head is movable, if any paper is jammed inside, and whether the printer is connected to a computer. On the other hand, if the PDA OS 40 is started through the PDA booting procedure 42 , these complicated hardware diagnostic steps are skipped, and the PDA system 40 pre-loaded into the storage device 13 (e.g. HD) of the notebook PC is directly started. The PDA utilities 41 are also loaded to quickly enter the PDA operating environment.
FIG. 7 shows a flowchart of another embodiment of the invention, which is based upon the procedure in FIG. 4 . It further provides PDA hot keys 16 for directly starting a specific PDA OS 40 after turning on the power (see FIG. 8 ). The number of PDA hot keys 16 is determined by the number of OS's installed in the notebook PC. Each PDA hot key 16 has a unique ID, which is stored in a hot key table 17 in the BIOS chip 11 . When the user presses any of the PDA hot keys 16 , the BIOS identifies the PDA OS from the hot key table 17 according to the PDA hot key 16 being pressed. The assigned PDA OS is then started. The detailed procedure includes the steps of:
B1. reading the information of all the OS's installed in the storage device 13 of the notebook PC from the MBR. B2. determining whether there are multiple OS partitions and continuing to the next step if there are, or otherwise running the booting procedure 32 of the basic OS 31 to start the basic OS; B3. detecting the PDA OS's 40 in the multiple OS partitions; B4. detecting any PDA hot key 16 being pressed, identifying the PDA OS from the hot key table 17 accordingly, and starting the assigned PDA OS and its utilities 41 ; otherwise continuing to the next step directly; B5. displaying the detected multiple OS's in a menu on an output device 14 for the user to select the OS to be started through an input device 15 ; and B6. starting the OS selected by the user.
While the invention has been described by way of example and in terms of the preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments. On the contrary, it is intended to cover various modifications and similar arrangements as would be apparent to those skilled in the art. Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements. | A method and system for starting a multiple PDA OS through a menu is disclosed. The invention mainly modifies the BIOS booting procedure in a notebook PC installed with multiple OS's. After the notebook PC is turned on, the multiple OS's are detected. These multiple OS's, including a PDA OS and a normal notebook PC basic OS (such as the Windows OS), are displayed on a menu. By ignoring some hardware diagnostic steps during the BIOS booting procedure and only performing hardware diagnoses for those input devices that support menu manipulations, the starting speed of the laptop can be accelerated. The user can thus start any OS by clicking the desired item in the OS menu. | 6 |
REFERENCE TO RELATED INVENTION
The present invention is a continuation-in-part of U.S. patent application Ser. No. 08/042,985, filed Apr. 5, 1993, now U.S. Pat. No. 5,386,817, which is a continuation-in-part of U.S. patent application Ser. No. 07/713,178, filed Jun. 10, 1991, now U.S. Pat. No. 5,201,908, both in the name of Jeffrey S. Jones, and incorporates those disclosures herein.
FIELD OF THE INVENTION
The present invention is directed to medical instruments in general and more particularly to the field of conventional endoscopes. The present invention is specifically directed to a collapsible access channel system for use with a conventional endoscope. The access channel provides a passageway for certain functions such as providing for suction, biopsy, air and water to be communicated to a patient's body cavity.
DESCRIPTION OF THE PRIOR ART
For purposes of the present invention, the term "endoscope" is intended to refer to a conventional endoscope, which includes an elongated substantially cylindrical portion, which portion is designed to enter a body cavity for examination and surgical purposes. All conventional endoscopes currently used in the market today include an elongated substantially cylindrical portion. One reason for this is to allow the distal end of the elongated portion to freely articulate in flexible endoscopes. Any shape other than a substantially cylindrical shape would hinder the required flexibility of the distal end. There are also rigid endoscopes which are substantially cylindrical but do not have an articulating distal end.
Endoscopes allow a physician to observe a body cavity and to insert medical instruments into the cavity for a variety of purposes. Medical instruments may take the form of many types of devices, for example, a biopsy device, an air tube, an irrigation tube and a suction tube.
Conventional endoscopes may also be fitted with a protective covering. Sanitary disposable protective coverings are used with endoscopes to shield the endoscope from a patient's body which may carry bacteria or viruses. These devices are known to the prior art. For example, reference is made to U.S. Pat. No. 5,201,908 to Jones which is incorporated herein by reference and is directed to a protective covering for a medical instrument, such as an endoscope. The covering includes an elongated hollow sheath having a wall of flexible material. The sheath includes auxiliary access tubes, providing a variety of functions, such as instrument manipulation and fluid removal.
In all endoscopy the main feature is to gain access to the body cavity being examined using the smallest diameter endoscope possible. With the present state of the art, this means that the size of the access channels and the subsequent instruments introduced is severly limited. All present scopes have the access channels built within the cylindrical confines of the scope. This limits the size of the instrument that can be introduced into the body cavity at any one time.
SUMMARY OF THE INVENTION
The present invention is designed to overcome the deficiencies of the prior art by providing a channel system for use with both flexible and rigid conventional endoscopes. The present invention will allow a smaller scope to gain access to a body cavity. Once access has been gained it is usually a simple procedure to dilate the cavity or orifice to allow entry of larger instruments or devices. The endoscope includes an elongated, substantially cylindrical portion having a first distal end and a second proximal end. The channel system comprises a collapsible channel with a first distal end and a second proximal end and is adapted to extend alongside and exterior to the cylindrical portion of the endoscope. The collapsible channel is provided with an access means communicating between the first end and the second end of the collapsible channel. The system also includes a means to attach the collapsible channel to the endoscope.
The invention is further directed to a channel system in combination with a conventional endoscope having an elongated, substantially cylindrical portion with a first distal end and a second proximal end. The channel system includes an endcap designed to fit over the first distal end of the of the endoscope. A collapsible channel is provided which is integral with the endcap. The collapsible channel is adapted to extend alongside and exterior to the elongated, substantially cylindrical portion of the endoscope. The system further provides for a passageway between the first and second ends of the collapsible channel.
An advantage of the collapsible access channel system is that it provides an auxilliary channel attachment for a standard endoscope. Thus, prior art endoscopes can be provided with a channel system allowing a passageway for instruments into a body cavity.
Further, the collapsible access channel of the present invention provides a means to allow more and/or larger instruments to be placed in a body cavity. An endoscope with the attached access channel in collapsed form is first inserted into the body orifice. After insertion an instrument, generally in the form of a tube or a biopsy mechanism, may be inserted into the access channel. As the instrument is moved along the access channel, the elasticity of the channel enables the channel to enlarge and conform to and fit the instrument. The body orifice also naturally dilates to conform to the enlarged access channel. The collapsible channel, therefore, provides a variable sized entrance into the body orifice depending upon the medical procedures that are required.
Additionally, more than one access channel may be attached to the endoscope. With several access channels, a variety of functional tubes and medical instruments may be inserted into the body cavity at one time to perform different functions. The body orifice or cavity will be dilated by the passage of additional devices through accessory channels. When the additional devices are inserted, the endoscope with an access channel attached will have a larger cross section than a naked endoscope. In the prior art, the access channels are rigid, necessitating a large initial endoscope cross-section which may hamper the insertion of the endoscope into the desired location.
Further objects, features and advantages of the invention will be apparent from the following detailed description when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view illustrating the collapsed channel with adhesive before attachment to an endoscope.
FIG. 2 is an elevated end view of the collapsed channel of FIG. 1 adhesively attached to an endoscope.
FIG. 3 is a perspective partial cutaway view of an alternative embodiment of the present invention showing an endcap with a collapsed access channel attached thereto placed on the distal end of an endoscope.
FIG. 4 is a side elevated view of embodiment illustrated in FIG. 3.
FIG. 5 is a cross-sectional elevated view along lines 5--5 of the collapsed channel shown in FIG. 4.
FIG. 6 is a perspective view of another embodiment of the present invention illustrated a now-expanded access channel integral with a protective sheath covering an endoscope.
FIG. 7 is a side elevated partial cutaway view of the embodiment illustrated in FIG. 6.
FIG. 8 is an end elevated view of the embodiment of FIG. 6.
DETAILED DESCRIPTION OF THE INVENTION
The present invention is generally directed for use with any medical instrument having an elongated tubular portion. The present invention is particularly applicable to a conventional endoscope having a substantially cylindrical or tubular portion. Depending upon the use of the endoscope, the endoscope tubular portion can vary in length from approximately 1-6 feet and is designed to enter a body cavity for examination and surgical purposes.
Specifically, the present invention is directed to an auxilliary channel system which may be applied to a variety of conventional endoscopes for examining the body. A collapsible access channel can be used with any flexible gastrointestinal scope or rigid instrument. Such examples include cytoscopes, upper endoscopes for the examination of the esophagus, stomach and duodenum, colonoscopes for examining the colon, angioscopes for examining blood vessels, bronchoscopes for examining the bronchi, laparoscopes for examining the peritoneal cavity, and arthroscopes for examining joint spaces.
Reference is now made to the figures where the same reference numerals refer to like features. FIG. 1 illustrates a channel system 5 with a collapsible channel 20 designed for attachment to a conventional, flexible basic endoscope 10 commonly used in the medical field. The construction of the endoscope 10 is well-known to the art and does not form a part of this invention. Reference is made to U.S. Pat. No. 4,809,678 to Klein, U.S. Pat. No. 4,825,850 to Opie et al., and U.S. Pat. No. 4,852,551 also to Opie et al. for a variety of descriptions for endoscopes. The endoscope 10 includes a first distal end 12 and a substantially cylindrical elongated flexible portion 14. The remainder of the endoscope is not illustrated.
In one of the preferred embodiments, the access channel 20, as shown in FIG. 1, is collapsed upon itself. The collapsible channel 20 has a first distal end 21, a second end 23, an inner wall surface 27, an outer wall surface 28. The access channel is made from a flexible, or more specifically ductile, material which may be elastomeric in the preferred embodiment. The component materials may be made from elastomeric material including polymeric resinous materials such as natural and synthetic rubbers, thermoplastic polymeric materials such as polyethylene, polypropylene, polyurethane, and combinations of natural or synthetic rubbers with thermoplastic polymeric materials such as rubber, modified polyethylene, rubber-modified polystyrene and the like. The length of the collapsible channel 20 is adjustable, but preferably similar in length to the length of the endoscope 10.
The access channel 20 is preferably adhered to the endoscope 10 by an adhesive material 22 as shown in FIGS. 1 and 2. Adhesive materials are known to the art and, by themselves, do not form a part of the invention. The adhesive material 22 is designed to be applied to the outer surface 28 of the collapsible channel 20. In alternate embodiments, the adhesive material 22 may be applied to the collapsible channel 20 as well as to the endoscope 10 or to the endoscope 10 only, where the collapsible channel 20 is to be attached. In the preferred embodiment, the adhesive material 22 applied to the outer surface 28 is attached to the endoscope 10 near the first distal end 12 between points 25 and 26. The collapsible channel 20 may also be attached to the endoscope 10 near the first distal end 12 between other points by any conventional means known to the art such as velcro, welding, or an attachment band.
In a preferred embodiment, the adhesive material 22 is a temporary connection to the endoscope 10 and the attachment may be released by pulling the collapsible channel 20 away from the endoscope 10 after it has been used. The adhesive material 22 positions the first end 21 of the collapsible access channel 20 near the first end 12 of the endoscope 10 such that the remaining unattached portion of the collapsible channel 20 is freely dissociated from the remaining portion of the endoscope 10. However, when the endoscope 10 is inserted into a body cavity, the collapsible access channel first end 21 which is attached to the endoscope first end 12 is inserted concurrently, trailing the remaining portion of the collapsible channel 20 which enters the body orifice adjacent and along with the endoscope 10. The collapsible channel 20 may be positioned within the orifice protruding into the body cavity a distance as far as required by the surgeon and as far as the endoscope 10 to perform the medical function required.
A significant feature of the collapsible channel 20, as shown in FIGS. 1 and 2, is its ability to collapse upon itself and then be inserted into a body orifice entering a body cavity in a flattened form. Once positioned inside the body cavity, an instrument or instruments may be inserted into the flattened collapsible channel 20. Upon insertion of such instrument at the second end 23, the collapsible channel 20 will expand around the instrument, to size, fitting tightly adjacent and conforming to the instrument through the body orifice. The expanded collapsible channel 20 adapts the body orifice, enlarging it and conforming it around the expanded collapsible channel 20. An advantage of this procedure is that the collapsible channel 20 allows large instruments to be placed within the collapsible channel 20 adjacent the inner wall 27 which provides a passageway 64, shown in FIG. 8, at the second end 23 communicating to a body cavity at the first end 21, when inserted. This is possible because a body orifice will enlarge slowly, not abruptly. Since the channel system 5 allows instruments to be inserted one at a time, a slow orifice dilation can occur, without tissue tearing.
In an alternate embodiment, an endoscope endcap 30 may also be provided, as illustrated in FIGS. 3-5, to fit over the first distal end 12 of the endoscope 10 and provide a means to releasibly attach the access channel 20 to the endoscope 10. In this embodiment, the endcap 30 only covers the distal end 12 of the endoscope 10. The endcap 30 has a first distal end 31, a second proximal end 32, an inner wall 33 and an outer wall 34. The distal end 31 of the endcap 30 may be provided with a window (not shown) covering the distal end 12 of the endoscope or a fitting ridge 31a which prevents the endcap 30 from sliding along the length of the endoscope 10.
The endcap 30 can be made of a number of materials known to the art. For example, the endcap may be formed from elastomeric materials which are flexible, such as, polyethylene, polypropylene, polyurethane and combinations of natural or synthetic rubbers with thermoplastic polymeric materials similar to materials used for the collapsible channel 20. The endcap 30 may also be constructed of semi-rigid or rigid plastic or rubber material, to form some structural integrity over the end of the endoscope 10. Preferred examples of materials include styrene, plexiglass and polyvinyl chloride.
As illustrated in FIG. 5, the endcap 30 surrounds the distal end 12 of the endoscope 10. The endoscope is illustrated with conventional parts including a main endoscope viewing channel 40 and at least one and preferably three access tubes 42 which are part of the endoscope.
In operation, the access channel 20 adhesively adheres to the endcap 30 as described above with respect to FIGS. 1-2. The endcap 30 is slidably placed over the distal end 12 of the endoscope 10. The endoscope 10 with the attached access channel 20 is now ready for use.
In another embodiment, shown in FIGS. 6-8, substantially all of the endoscope 10 is covered with a covering or sheath 50 as described in U.S. Pat. No. 5,201,908 to Jones, which is incorporated herein by reference. The sheath 50, is a flexible, loose-fitting covering designed to be placed over the endoscope 10. Substantially impervious to gas and water, the sheath 50 protects the endoscope 10 from the invasion of contaminants. The sheath 50 material can be elastomeric made from similar materials as described earlier for the collapsible channel 20.
The sheath 50 has a wall 52 including an inner wall surface 54 and an outer wall surface 56 and is integral with the collapsible access channel 20. The collapsible access channel 20 extends in axial fashion along the wall 52 of the sheath 50 from the first end 51 to a second end 60, shown in FIG. 7. The sheath 50 is also provided with an endcap 70 over the first end 12 of the endoscope 10. The endcap 70 provides structural integrity and protection for the end of the endoscope 10.
The access channel 20, shown in FIG. 7, is integral with the sheath 50 along the entire length of the sheath 50 but extends further than the sheath 50 from the first end 21 to the second end 23. The word integral, in this context, means that the outer wall 28 of the access channel 20 is identical to the sheath inner wall surface 54 and that the channel inner wall surface 27 is identical to the sheath outer wall surface 56, as shown in FIG. 7 within the broken section. The broken section also shows that the sheath wall 52 is located adjacent an endoscope wall 53. The second end 23 provides an opening 60 sized to receive a device such as a funnel 62 to provide an access means, or passageway 64, as shown in FIGS. 6 and 8, for a variety of tubes 66 such as suction tubes, water tubes or air tubes, or instruments to be inserted into the opening 60 and the access channel 20. Since the collapsible channel 20 may be dimensioned with a passageway 64 diameter larger than the endoscope 10 diameter, there are many devices available to a physician that could be placed within the collapsible channel 20 for access into a body cavity.
The channel system 5 may comprise, in alternate embodiments, a plurality of collapsible access channels 20. The plurality of access channels 20 may be separate tubular collapsible channels extending axially along the endoscope 10 to allow more than one instrument or fluid tube to be used concurrently. The access channel 20 may extend alongside the endoscope 10 preventing contamination of the air, water, suction, and biopsy tubes, avoiding the necessity of cleaning and sterilizing the instruments.
A method of using the collapsible channel 20 will now be described. In the illustrated embodiments, a collapsible access channel 20 is depicted with an endoscope 10. Many of the newer endoscopes are small, for instance, 4-5 mm. in circumference. These tiny scopes will allow a collapsed, flexible access channel 20 with a diameter that is larger than the endoscope 10 diameter to be attached to the scope and inserted into a body cavity with the endoscope 10. The access channel 20, in its collapsed, compact form, (shown in FIGS. 1-5), is inserted into a body cavity attached to an endoscope 10. Instruments, such as biopsy tools, fluid tubes and suction tubes, etc. are then inserted into the funnel 62 and eased along the passageway 64 one at a time toward the first end 21. As the instrument, or tube 66, passes the cavity orifice, the collapsible channel 20 conformably expands, as shown in FIGS. 6-8, to receive the instrument. The orifice dilates to allow the collapsible channel 20 to expand around the inserted tube 66. The collapsible channel 20 and the body orifice both conform to the increased circumference without tearing. In this manner, the inserted instrument or tube 66 may be manipulated by a surgeon to perform a medical task, such as a biopsy, or regulating fluid flow.
It is understood that the invention is not confined to the particular construction and arrangement herein illustrated and described, but embraces such modified forms thereof as come within the scope of the following claims. | A channel system for use with a conventional endoscope is provided. The system comprises a collapsible access channel that is connected to a first distal end of the endoscope. The collapsible channel includes an access opening communicating between the two ends of the collapsible channel. The endoscope may be provided with a protective sheath and/or an endcap that is integral with the collapsible channel. The collapsible access channel allows a physician to insert functional instruments such as a biopsy device or tubes for supplying air, water, suction and irrigation. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Not Applicable
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable
REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISC APPENDIX
[0003] Not Applicable
BACKGROUND OF THE INVENTION
[0004] The present invention relates in general to heat engines that utilize an external heat source such as solar, geothermal, combustion, waste heat etc., to produce work for driving generators or producing electricity otherwise, driving pumps, driving shafts etc., and for producing heating and cooling. This field of energy production has become more attractive with ever-rising fuel prices and concerns for emissions and global warming. However, these engines are still not attractive enough an option to be taken seriously as a replacement for the internal combustion engine in just about all applications. This is due to the fact that all but the most expensive, exotic designs waste a tremendous amount of heat since it is very difficult for these types of engines to efficiently utilize a heat source. These heat engines require a very large ΔT between their heat sources and their heat sinks to run efficiently, requiring exotic materials and complex designing, rendering them more of a novelty of design, rather than engines of practical use. In addition, they require massive heat exchangers to transfer heat necessary for efficient operation, making them cumbersome, heavy, and expensive. If a heat engine could be developed that could solve one or more of these disadvantages or lessen the extent thereof, then it could be much more competitive in today's market.
BRIEF SUMMARY OF THE INVENTION
[0005] The present invention overcomes these limitations by being relatively inexpensive to build and maintain using conventional readily-available components, that can efficiently utilize not only large ΔT's between its heat source and heat sink, but also minor ones, and that doesn't require the massive expensive heat exchangers of conventional heat engines, to make it a much more attractive alternative to internal combustion engines, as well as an excellent choice for eco-fuel and solar energy production.
[0006] The present invention is a high performance modular heat engine that utilizes a highly pressurized working gas (defined as gas over 100 psi prior to engine startup) and hydraulic fluid within a pipeline, tube or flow circuit to produce power hydraulically or otherwise. It does this by adding heat to the high pressure working gas from a heat source via a control loop, isolated from the working gas and hydraulic fluid, to increase the working gas' pressure and impart movement to the hydraulic fluid, acting as a piston. This propels the piston down through the pipe or tube, further compressing the already highly pressurized working gas ahead of it and generating high compressive temperatures as a result. This is the first half of the engine's operation cycle, during which, heat is extracted from compressing the gas (its heat of compression or HOC) and temporarily stored in the control loop for use in the coming second half of the engine's cycle. This extraction of the working gas' HOC allows for isothermal compression of the working gas. When the piston reaches the end of the piston pipe or tube, the heat source once again adds heat to the isothermally compressed working gas via the control loop, as well as the stored HOC to raise the working gas' pressure and propel the piston back the opposite direction. Heat is continually supplied by the control loop to the working gas behind the piston during its expansion so that it remains isothermal, while simultaneously extracting the HOC ahead of the piston within the pipe or tube so that its compression remains isothermal. Once again, when the piston reaches the end of the pipe or tube, heat from the heat source and the prior cycle's HOC is added to the isothermally compressed working gas just the same as described in the previous cycle, to propel the piston back again in the initial direction. This cycle repeats back an forth through the piston pipe or tube forming the continuous operation of the engine. The control loop's role in all of this is that it is an independent liquid flow loop, out of direct contact with the engine's working gas, that controls the operation of the engine's cycle. It connects fluid-filled heat exchangers within each end of the piston's pipe or tube to similar heat exchangers for both the heat source and the heat sink, so that heat may be transported from the heat source to the piston's pipe or tube, or from the piston's pipe or tube to the heat sink, simply by circulating liquid flow from one to the other. The control loop resides outside the piston's tube and may be an open or closed system. Closed systems have the advantage of being able to operate at any pressure, while open systems (open to the environment) can easily accommodate very large systems. The control loop also controls the extraction and re-addition of HOC to and from the piston's pipe or tube during compression and expansion to maintain isothermal conditions. The advantage of having a highly pressurized working gas within the piston's pipe or tube (up to tens of thousands of psi) is that even relatively small temperature rises in a highly pressurized gas produces significant rises in pressure. Inversely, even relatively minor compression ratios in such highly pressurized gas produces significant rises in temperature. Combine the two and you have the ability in the present invention to utilize even minimal heat sources to impart significant useful energy into the engine's piston to convert high or low temperature working gas propelling the piston on one side, into much higher temperature working gas being generated on the other. This high temperature working gas created is very useful in heat engines and can greatly boost the present invention's efficiency and power output over conventional heat engines. The present invention uses this ability to produce large amounts of usable energy within its working gas from not only the hard to produce large ΔT's (hundreds to thousands of degrees) between its heat source and heat sink that conventional heat engines need to operate efficiently, but also minor ones (tens of degrees) that are readily available anywhere such as solar, or even ambient air. An advantage of the present invention over conventional heat engines in its ability to extract and return the HOC produced during the engine's operation is that this is heat normally discarded as waste by conventional heat engines but is a very important source of heat for the present invention that not only boosts its efficiency, but allows the conversion of normally useless low-grade heat to very useful high grade heat. HOC temperatures can rise very high, even above those of a heat engine's high temperature heat source, producing an artificial “peak” operating temperature. For example, the present invention has the ability to utilize a heat source and heat sink having a low ΔT in that by using the available energy within a low ΔT heat source to initially propel its piston, it can ultimately produce through its HOC, high temperatures and a resultant high ΔT engine operating cycle.
[0007] To understand all this better, let's take a quick look at the example provided in the drawings. At quick glance the engine looks like a industrial piping system, and rightfully so since this is just one way the engine can be built, having the same simplicity and flexibility of being able to route the flow paths of its working gas and hydraulic piston, as well as its control loop fluid in virtually any direction to follow a designer's preferred layout. The engine example as it is presented in the diagrams, utilizes water and air as its hydraulic fluid piston and high pressure working gas respectively, and is provided for conveying the general concept of the engine only, since numerous designs are possible, ranging from applications for utility power generation whereby the high-pressure piping may span several hundred yards, to that of powering laptop computers whereby the high-pressure piping is replaced by a micro-sized hydraulic circuit. This engine example illustrated here is made up of a long length of high-pressure pipe, having an air-filled pressure vessel on each end. Water that will act as the engine's piston, and twin hydraulic motors for extracting work, and check valves lie inbetween the two ends of the piping. The hydraulic motors and check valves can be replaced with any variety of commercial or otherwise hydraulic power take-off scenarios. A low pressure liquid-filled “control loop” is made up of a coiled tubing-style heat exchanger positioned within each air-filled pressure vessel, a heater coil tubing-style heat exchanger/heat source combination, and a cooling coil tubing-style heat exchanger/cooling fan “heat sink” combination. Also part of the control loop is a circulation pump connected to, and positioned between the twin heat exchangers, to control the input and output of heat through the air within the high-pressure piping. The section of the control loop spanning between the top of each heat exchanger within the pressure vessels and the heat source represents the regenerator of the engine (not to scale) and serves to extract heat from, and return heat to, the working gas within the pressure vessel during engine operation. A high-pressure hydraulic priming pump exists along the high pressure piping and serves to initially pressurize the working gas (for this example “Air”) hydraulically to very high pressure (several thousand psi) prior to its startup by pumping hydraulic fluid (for this example “water”) into the high pressure piping, compressing it. This is practical for large systems such as those used in utility power generation, although small engines can use a permanently sealed high-pressure gas. So now the working gas is pre-pressurized via the priming pump to several thousand psi. After this is done, heat from the heat source (a high temperature solar collector for this example) is applied to the heating coils of the control loop while a fan blows over the cooling coils of the control loop on the opposite side to maintain a low temperature there. Once the circulation pump is turned on the hot liquid from the control loop heating coils is circulated through the heat exchanger within the first pressure vessel, heating up the working gas and raising its pressure, while the cool liquid from the cooling coils is circulated through the heat exchanger within the second pressure vessel maintaining the working gas there at a minimum temperature and pressure. The flow of liquid through the control loop oscillates back and forth through its own tubing and that of the heat exchangers but never completely around, so that the cool liquid always remains on the cool side of the control loop and the hot liquid always remains on the hot side of the control loop. The high pressure working gas of the first pressure vessel seeks to travel to the relatively low pressure working gas of the second pressure vessel, moving all of the hydraulic fluid (the piston) existing between them along the way as it does. As this happens, the working gas of the second pressure vessel is compressed while its heat of compression is extracted by the cool liquid of the control loop. This extracted heat is not wasted and will be later returned to the working gas for performing work. This movement of hydraulic fluid operates one of the hydraulic motors (a single motor may be used in lieu of the twin presented here) within the flow path, performing work on an external generator. This is the engine's initial power stroke. When the maximum compression is reached within the second pressure vessel's working gas, the circulation motor is reversed, causing the flow within the control loop to travel in the opposite direction. This now circulates the hot liquid of the heating coils through the heat exchanger of the second pressure vessel, heating up the working gas and raising its pressure, while circulating the cool liquid of the cooling coils through the heat exchanger of the first pressure vessel, maintaining the working gas there at a minimum temperature and pressure. Once again, the high pressure working gas tries to seek a path to the relatively low pressure working gas, this time in the direction from the second pressure vessel to the first, pushing the hydraulic liquid between them in the opposite direction and operating the second hydraulic motor within its flow path, and also performing work on the external generator. This is the engine's return power stroke. Like with the engine's initial power stroke, when the maximum compression is reached within the first pressure vessel's working gas, the control loop's circulation motor is reversed, causing the flow within the control loop to travel in the opposite direction with the hot liquid going to the first pressure vessel's working gas and the cool liquid going to the second pressure vessel's gas, and the cycle then repeats itself continuously as the operation cycle of the engine.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0008] FIG. 1 is a diagram of one embodiment of the present invention using solar heat as its heat source, in a shut down ambient state.
[0009] FIG. 2 is a diagram of the same embodiment prior to startup where its working gas is being hydraulically pressurized.
[0010] FIG. 3 is a diagram of the same embodiment during its initial power stroke.
[0011] FIG. 4 is a diagram of the same embodiment whereby the liquid flow within the engine's control loop is reversed prior to the start of its return power stroke.
[0012] FIG. 5 is a diagram of the same embodiment during its return power stroke.
DETAILED DESCRIPTION OF THE INVENTION
[0013] This example utilizes solar heat to generate power although any heat source such as combustion, nuclear, waste heat etc. may be substituted in its place and its piping layout may take virtually any form from vertical to horizontal, from smaller than an inch to several hundred yards or more. All of its other parameters such as working gas and hydraulic fluid may also be varied to suit a given application.
[0014] Referring to FIG. 1 , with the engine shut down water rests within the bottom high-pressure piping 18 and hydraulic motors 21 & 24 . Air fills the upper portion of the high pressure piping as well as both pressure vessels 10 & 11 . Oil completely fills the low pressure control loop made up of the heating coil 13 heated via a solar collector 12 , cooling coils 19 cooled via a fan 16 , a fractional hp circulation pump 20 , heat exchangers 14 & 15 and low pressure piping 17 connecting them all together. The entire engine system is unpressurized at ambient temperature.
[0015] Referring to FIG. 2 , the pressurizing pump 25 is turned on which pumps external water into the high pressure piping 18 , raising its level and compressing the air above it. The pump 25 continues until reaching the engine's operating pressure of several thousand psi. The pump 25 is turned off and will not be used again until the engine will need to be started up again in the future. At the control loop, solar energy is continually focused on the heating coils 13 , heating the oil inside while the battery-operated fan 16 is switched and left on, cooling the oil inside the cooling coils 19 .
[0016] Referring to FIG. 3 , when the heating coils 13 reach the desired temperature a thermocouple switches on the battery-operated circulation pump 20 causing the oil within the control loop to flow clockwise. As this happens the hot oil from the heating coils 13 flows through the coils of heat exchanger 15 while the cool oil from the cooling coils 19 flows through the coils of heat exchanger 14 . The hot oil entering heat exchanger 15 heats the high pressure air within the surrounding pressure vessel 11 raising the air's pressure while the cool oil entering heat exchanger 14 cools the high pressure air within its surrounding pressure vessel 10 keeping temperature and pressure to a minimum. The flow of oil from the control loop never travels past the opposite end of the heat exchangers 14 & 15 so that the hot oil never reaches the cooling coils 19 and the cool oil never reaches the heating coils 13 . The rising air pressure in pressure vessel 11 pushes against the water piston in the high pressure piping 18 below it, forcing it clockwise through the piping as it seeks the lower pressure air of the pressure vessel 10 , creating the engine's initial power stroke. The water piston flows through the upper hydraulic motor 21 which can be of any variety (piston, rotary, turbine etc.) that in-turn, turns a generator for recharging the control loop battery and providing external power, but is prevented from passing through the lower motor 24 due to the one-way check valve 23 in front of it. A single hydraulic motor equipped with a directional switching valve could replace the twin motors 21 & 24 presented here. The water continues to flow towards pressure vessel 10 , compressing further its already highly pre-pressurized air while it is simultaneously cooled via the cool oil circulating through heat exchanger 14 from the cooling coils 19 of the control loop so that its compression is isothermal. Heat of compression developed within the air is removed via the heat exchanger 14 and serves to pre-heat oil that will be later return to the same air of pressure vessel 10 during the engine's return power stroke. This HOC is temporarily stored within the control loop piping existing between the heat exchanger 14 and the heating coils 13 .
[0017] Referring to FIG. 4 , when the water level rises to its maximum height within the high pressure piping 18 below pressure vessel 10 that coincides with the maximum pressure attained within the pressure vessel 10 (the water level never reaches as high as the heat exchanger 14 ), either a water level switch or a pressure switch within the high pressure piping 18 below pressure vessel 10 is activated. This switches the direction of the control loop's circulation motor 20 and in-turn switches the direction of flow through the control loop to counter-clockwise. The reversal of flow within the control loop causes the extremely hot oil within the heating coils 13 to flow to the coils of the heat exchanger 14 , preceded by the hot oil possessing the heat of compression given off by the air as it was being isothermally compressed during the first power stroke, that had just left the upper coils of the heat exchanger 14 and was stored between it and the heating coils 13 when the flow through the control loop was clockwise. The hot oil entering the heat exchanger 14 from the top pushes the existing cooler oil within the heat exchanger (since it has given up heat to the air), out through its bottom and back to the cooling coils 19 of the control loop where any remaining heat can be removed so that once fully cooled, it can be used in the next power stroke. This remaining heat is “waste heat” and may be used for a variety of purposes such as pre-heating oil leaving the top coils of the heat exchanger 15 on its way to the heating coils 13 that will be used in the next heating cycle, providing heat to the air as it expands isothermally through the high pressure piping 18 by allowing it to flow through coaxial piping surrounding it as it follows the expanding air through it, or for external use such as heating, refrigeration or powering secondary heat engines. To repeat what was just said earlier, the preceding volume of hot oil entering the heat exchanger 14 gives up its heat (the heat of compression absorbed during the first power stroke's isothermal compression of the air within pressure vessel 10 ) back to the same now highly compressed cooler air, immediately raising its pressure. This preceding volume of hot oil is followed by the extremely hot oil of the control loop's heating coils 13 that heats and raises the air's pressure to its maximum. In the mean-time the reversal of flow within the control loop has also caused the cool oil that had been sitting within the cooling coils 19 to flow to the coils of the heat exchanger 15 , pushing the existing still warm oil out through the top of the heat exchanger and back to the heating coils 13 where it will be further heated for use in the next power stroke. The cool oil entering the heat exchanger 15 cools the hot air within the pressure vessel 11 and reduces its pressure.
[0018] Referring to FIG. 5 , now with high pressure hot air in pressure vessel 10 and minimal pressure cool air in pressure vessel 11 , the air in pressure vessel 10 pushes against the water in the high pressure piping 18 below it, forcing it counter-clockwise through the piping as it seeks the lower pressure air of the pressure vessel 11 , creating the engine's return power stroke. This power stroke is identical to that of the first, just in the opposite direction. The water flows through the lower hydraulic motor 24 turning either a second generator or the same generator as that of the upper hydraulic motor 21 , but is prevented from passing through the upper motor 21 due to the one-way check valve 22 in front of it. The water meanwhile compresses the air in pressure vessel 11 isothermally while the cool water of the flow loop passing through heat exchanger 15 absorbs its heat of compression just as in the initial power stroke with pressure vessel 10 . Once again, when the maximum air pressure is reached, the control loop is switched via a water level or pressure switch and the cycle repeats itself with the hot oil of the control loop's heating coils 13 flowing back into the heat exchanger 15 of pressure vessel 11 preceded by the heat of compression oil, while the cool oil of the control loop's cooling coils 19 flows back into the 14 heat exchanger of pressure vessel 10 .
[0019] Considering all other things equal, the longer the length of the initial and return power strokes of the engine, the higher the efficiency of the engine. This is true since much more of the heat inputted into the heating coils is utilized for expanding the working gas and performing work before being lost during the switching of the control loop's direction, whereby thermal losses occur each time cool oil replaces hot oil in the heat exchangers and vice-versa, and heat is added and removed from the working gas.
[0020] It would not be uncommon to have a municipal power station having its high-pressure piping extending several hundred yards, permitting the hydraulic fluid to travel over the span of several minutes through the hydraulic motor(s) between each initial and return power stroke. Obviously there are practical limits to how long a pipeline can extend before factors such as losses due to internal friction become overwhelming. In addition, the momentum of the water column within the high pressure piping plays an important factor in the level to which the working gas within the pressure vessels can be compressed. For example, a column of water traveling through the high pressure piping at a fast speed will impart more energy into the air within the pressure vessels than the same column of water traveling at a slow speed, and a long column of water will impart more energy than a short one of the same speed. The advantage of using long columns is that such columns can carry great momentum with them that can hit the working gas very hard, spiking its temperatures and pressure. This is especially true of what would be envisioned as the most efficient design of this type of engine whereby liquid metal is used as both the liquid within the control loop and the hydraulic fluid within the high-pressure piping. This serves two advantages. The liquid metal can accommodate extremely high temperatures and carries a very high mass capable of delivering a maximum compression and temperature “spike” on the working gas limited only be the materials capabilities of the high-pressure pipeline and the pressure vessel. Such high temperatures in the thousands of degrees can disassociate a working gas, for example steam into H2 and O2 and then recombine to steam, releasing heat and driving the temperature and pressure of the working gas up even higher, producing the maximum efficiency attainable from the engine, to the point whereby the heat inputted to the heating coils from a heat source can be reduced, while maintaining the cycle. A free-piston made up of a long solid column of ceramic, alloy or steel can be substituted for the liquid metal within the high-pressure piping to perform the duty of compressing the working gas, in which case, power would be extracted from the system via the working gas or via electrical generation between a conductive/magnetic design between the high-pressure piping and the piston.
[0021] The high pressure piping of the present invention can exist anywhere between an upright vertical position to a horizontal position just so long as it maintains the working gas within the pressure vessels and the hydraulic piston's integrity.
[0022] The heat exchangers/pressure vessels of the engine are very similar to shell in tube-type heat exchangers and may be substituted, as well as any suitable heat exchanging/vessel combination that allows the same type of heat transfer between a control loop and a pressurized working gas while having the working gas in communication with a hydraulic fluid for purposes of pumping the fluid.
[0023] The pressurizing pump needs to be able to seal against backflow after its has hydraulically pressurized the working gas. If a particular type of pump cannot fulfill this then a check valve, shut off valve or other means must be employed within the line to do so.
[0024] The solar collector represents just one means for heating the heating coils and any other heat source such as solar panels, nuclear, geothermal, combustion, process waste heat, warm bodies of water, waste heat from fuel cells, transformers, electric motors and combustion engines may also be used.
[0025] Heating and cooling coils are just one way of constructing a means whereby heat may be added or taken away from the control loop fluid. Other means such as passing the fluid through a porous thermally conductive media or using many of the various commercial heat exchangers may also be used.
[0026] The fan represents just one means for removing heat from the cooling coils and any other means such as refrigeration coils, evaporative cooling, natural air convection, household or city water, bodies of water, burying underground etc. may be used.
[0027] Oil was used as the fluid within the control loop although any liquid, gas, solid, slurry or combination thereof may be substituted as long as it is able to transport heat to and from the working gas of the engine for the purposes of sustaining the engine's operation.
[0028] Water and air were used in the pressure vessel and high pressure piping although any suitable combination of liquid/compressible gaseous media may be used, including the use of slurries or suspended solids within the liquid.
[0029] A barrier such as a bladder, bellow seal, diaphragm, free-piston, secondary liquid etc. may exist between the working gas and the hydraulic fluid of the high pressure piping to seal between them where contamination or incompatibility may be a concern.
[0030] A logic controller may be employed to create specialized thermal engine cycles by regulating the flow of fluid within the control loop to provide isothermal, adiabatic or other conditions for the working gas, or for creating unique power curves during the engine's power strokes in real-time. As well, the control loop may possess any necessary devices such as switches, sensors, valves, external fluid sources, heat input or output means, individual controllers for the heating and cooling coils etc. for accomplishing a particular job of managing the operation of the overall engine.
[0031] It would be preferred to have the inner walls of the pressure vessels and regenerator areas of the control loop lined with a thermally non-conductive material such as ceramic etc. so that thermal losses are minimized.
[0032] The present invention can exist on its own or as an integrated part of a larger system.
[0033] A metering pump can be used instead of a circulation pump within the control loop to provide for more accurate flow.
[0034] Instead of having twin motors on a common main line the high pressure piping may be divided right at the base of the pressure vessels into two or more separate lines to feed the hydraulic motors or other devices and/or processes individually. A single hydraulic motor may exist combined with directional flow switching valves to maintain a common directional flow through the motor regardless of the direction of flow through the high-pressure piping.
[0035] The high-pressure piping can be thermally insulated to prevent the input or loss of heat from it depending on what is advantageous for a particular application. Without insulation, a simple means to provide cooling of its high-pressure piping can be done using natural convection or conduction etc., especially on long pipe runs.
[0036] If it is desired to utilize part of the engine's heat for external use such as heating, low grade heat can be extracted at the cooling coils and high temperature heat can be extracted at the regenerator, providing enough regenerative heat is still available to sustain engine operation.
[0037] The following are several ways for carrying out refrigeration and cooling cycles within the engine:
[0038] Heat rejected from the control loop can be used to power an absorption-type refrigeration system.
[0039] During normal operation of the engine the column of hydraulic fluid moves back and forth within the high pressure piping, compressing the working gas within the pressure vessels and the heat of compression is removed each compression stroke by the heat exchangers. Each cycle we are left with relatively cool high pressure working gas alternating in each of the pressure vessels. Now during each cycle, before the control loop circulates the hot liquid from its regenerator and heating coils to the highly compressed working gas of the pressure vessels to initiate their power strokes, a portion of that working gas can be bled off for refrigeration purposes. Refrigeration piping made up of a valve, an expansion nozzle and a heat exchanger can exist straight across and mid-way between the pressure vessels. Since at the end of each power stroke we always have one pressure vessel at a higher pressure than the other we can use the lower pressure of the opposing pressure vessel as a target to exhaust the gas of the higher-pressure vessel, creating the cooling effect desired. A second nozzle and heat exchanger can exist between the pressure vessels going the opposite direction for the return power stroke, or a common nozzle and heat exchanger may be shared between the two through valve switching. This refrigeration cycle would continue back and forth between the two pressure vessels as long as the engine operates, but can be switched on or off simply by allowing or not allowing the refrigeration valves to operate. The exhausted gas within the lower pressure vessel is then simply compressed during the opposing pressure vessel's power stroke. The engine can be dedicated to the refrigeration cycle so that all of its working gas over that amount necessary to maintain operation of the engine is used for refrigeration, in which case, hydraulic motors would not be needed in the engine, or only part of it may be bled in cases where it is desired to still extract work from the hydraulic motors. The amount of working gas bled for refrigeration purposes can be up to that amount over what is needed to sustain operation of the engine, whether for supporting the refrigeration cycle only or for driving motors as well.
[0040] A second type of refrigeration cycle operates similar to the one just described, except that now we will use the liquid of the hydraulic piston to produce cooling. In this case the hydraulic fluid used for the piston must be of one suitable for refrigeration purposes such as ammonia, commercial refrigerants, butane etc., just to name a few. While at or near the end of its power stroke the hydraulic piston is under great pressure. It is here that part of it can be bled away in liquid form so that it can be expanded through an expansion nozzle and heat exchanger like in the first example, or evaporated over a heat exchanger surface and then transported over to the pressure vessel for re-introduction into the system preferably at a point of least pressure during the engine's cycle.
[0041] The heat absorbed by the working gas or hydraulic piston during these refrigeration cycles can be added to the working gas on the expansion side of the piston during engine operation to assist in providing energy to it for driving the piston or may be used externally for heating purposes etc.
[0042] One may also use a secondary liquid or gas other than that of the hydraulic piston or working gas for refrigeration purposes that can be externally introduced into the pressure vessels preferably at points of lowest operating pressure for purposes of utilizing the hydraulic piston to pressurize them for refrigeration use external to the engine such as to cool the engine heat sink or use elsewhere.
[0043] By driving the hydraulic motor(s) via an external motor drive that moves the hydraulic fluid back and forth within the high-pressure piping, compressing the working gas within the pressure vessels, the engine, now becoming a heat pump that can may produce the same refrigeration and heat-producing cycles previously mentioned. The hydraulic motors however, should be of a type such as piston, that make good pumps while operating in reverse (being driven instead of driving). If the system is dedicated as a heat pump and will never run as an engine then pumps ideally suited for this type of application can be chosen.
[0044] Up till now it has been shown how the engine can drive a generator and produce refrigeration and heating. The engine can also perform all of these functions simultaneously for tri-generation purposes.
[0045] The engine can be designed using a common media for both the hydraulic fluid of the high-pressure piping and the working gas such as liquid propane/propane gas. In this type of design, not only can the working gas be bled off to supply the high pressure/highly heated combustion fuel for providing heat to the heating coils, but provides a good refrigeration media, and makes a convenient system for residential or commercial use whereby existing propoane storage tanks can be utilized for not only providing heating, but for refrigeration, air conditioning, and electrical generating needs as well.
[0046] The engine can create specific areas of lowered pressure within its high pressure piping by having an ejector type venturi device in the line that would accelerate the hydraulic fluid or working gas, creating an area of low pressure at its nozzle, for supporting any of the forementioned processes as well as any others a designer may wish to create.
[0047] The engine can compress its working gas for external storage and future use by introducing additional compressed gas from an external source into the pressure vessel(s) preferably at the point when the working gas' pressure during its power stroke is at a minimum. By producing a rapidly moving column of hydraulic fluid within the high-pressure piping, the column of hydraulic fluid possesses momentum that will continue to compress the working gas at one pressure vessel even though the hot expanding gas at the other pressure vessel has lost much of its pressure. It is at this time that external gas may be pumped through a valve into the lower pressure vessel. When the next power stroke sends the water column back to the pressure vessel that external gas was added to, it can pump the extra added gas from that pressure vessel at a point when its pressure is at its maximum, as determined by a valve setting, through a valve for external use at a much higher pressure than when it went in. The external gas' heat of compression can be utilized by the engine for performing work just as it does for its working gas. If it is desired to use the externally pumped gas for refrigeration, then it can be expanded for such a purpose.
[0048] In a similar manner to the compressor mentioned above, the engine can be designed to pump liquids as well for purposes of propulsion, powering external hydraulic systems, providing pressurized water for reverse osmosis systems or for transporting liquids. For example, external pressurized water existing at a pressure higher than that of the working gas at its minimum power stroke pressure can be pumped during operation into the area of the engine's high pressure piping behind the water column within, preferably at the point in the engine's power stroke when the pressure vessel at that end has its pressure at a minimum. On the return stroke of the engine, prior to the water column reaching the top of the high pressure piping and being at its maximum pressure, a valve is opened along the piping allowing the volume of water originally added during a state of lower pressure, to be extracted at a much higher pressure for use such as for filling a water tower, hydraulic propulsion, utility water supply etc. An in-line flow meter can regulate the amount of water extracted before the valve is closed until the next cycle.
[0049] It is the control loop that determines the pressure, flow rate, timing etc. of the working gas and hydraulic fluid within the pressure vessels and high-pressure piping. This control loop can be designed to be variable during operation to modulate the output of the engine by having variable heat input and heat removal as well as by having the ability to speed up, slow down, or halt the flow of fluid through it at any time. For the control loop to control the engine as described in FIGS. 1-5 the volume of flow within the control loop piping from and including the heating coils to the top of either heat exchanger essentially equals the volume of flow from the top of either heat exchanger to its bottom. Likewise, the flow within the control loop piping from and including the cooling coils to the bottom of either heat exchanger essentially equals the volume of flow from the bottom of either heat exchanger to its top. This provides so that the cool water of the cooling coils never passes up into the heating coils and vice-versa during operation so that heat from the heating coils is not wasted.
[0050] However, it is up to the designer to determine the particular operation of the engine and one may decide to have half the flow volume within the control loop as that of the heat exchangers.
[0051] The engine can use a fluid exchange pump (U.S. Pat. No. 4,818,187) existing as part of the high pressure piping whereby a section of piping moves in and out of flow alignment with the hydraulic fluid flow for the purposes of introducing and removing external fluids from the piping. For example, when the power strokes minimum pressure is reached within the pressure vessels, the section of high pressure piping experiencing the minimum pressure gas can be rotated out of the pipeline and replaced with an equal volume of liquid or higher pressure gas, for the purposes of pumping the liquid or higher pressure gas from the pipeline at a higher pressure than when the return power stroke occurs.
[0052] A free piston or multiple free pistons may exist within the engine having a straight high pressure pipeline so hat the hydraulic fluid moving back and forth between the pressure vessels on each end carries the piston(s) with it. Free pistons can exist at the mid-point through the high pressure piping, at each end of the hydraulic fluid column, or can exist in large numbers throughout, just so long as they do not collide with motors, themselves or other components of the pipeline. There may be numerous small pistons or a single large piston. These pistons can have spacers in-between them so that they maintain their distance between each other. They can be provided with seals between them and the piping walls to better catch the flowing fluid or ride on bearing surfaces to reduce friction and pipe wall wear. They may be elliptical riding within an elliptical cross-sectional pipe to increase bearing surface area. They can be made of any suitable material and offer the advantage of providing added momentum to the engine's power stroke when heavy materials are used. They also can produce electricity by making them out of copper or some other conductive material while lining the pipeline with electro or permanent magnets or vice-versa, with electrical leads connected to the piping to transfer the AC or DC externally. In a reverse fashion, current can be applied to the electro-magnets to impart movement in the pistons for pumping purposes. The spacing of multiple pistons can produce a particular frequency as they flow through the high-pressure piping, dependent on their spacing and velocity.
[0053] The present invention may be utilized in the magneto hydraulic production of electricity whereby a conductive liquid such as liquid metal, seawater etc. is passed through a MHD generator within the high-pressure pipeline, while electrical leads are connected to the generator to extract current for external use.
[0054] The engine may incorporate a double-acting piston connected to a flywheel and external shaft on a single straight length of high pressure piping to replace both hydraulic motors, valves and split piping mid-point through the high pressure hydraulic piping of FIGS. 1-5 , so that the top of the piston is exposed to the hydraulic fluid of pressure vessel # 1 and the bottom of the piston is exposed to the hydraulic fluid of pressure vessel # 2 . When higher pressure exists in pressure vessel # 1 and lower pressure exists in pressure vessel # 2 , the higher pressure pushes against the top of the piston, driving it to the right, and when the higher pressure exists in pressure vessel # 2 and lower pressure exists in pressure vessel # 1 , the higher pressure pushes against the bottom of the piston, driving it to the left. This force is in-turn translated to the flywheel to smooth out operation and then outputted to the external shaft for use. The volume flow of hydraulic fluid through the high-pressure piping of the engine is limited to the volume of each stroke of the piston. The piston in this example can be replaced with any number of conventional or innovative hydraulic motor arrangements sand is an attractive design for small engines that cannot accommodate long hydraulic piping circuits.
[0055] By controlling the speed of water column in the high pressure piping, the HOC temperature can be controlled so that an optimum delta T can be maintained between the working gas and the surrounding control loop heat transfer media designed to absorb it.
[0056] The engine can operate using only a moderate temperature heat source, in which case the engine's HOC' temperature may exceed that of the heat source's in which case, after the working gas is compressed within the pressure vessels, the control loop will circulate to enable the heat from the heat source to flow through the heat exchangers of the pressure vessels prior to the regenerative heat.
[0057] The control loop can use evaporative cooling or its heat to operate an absorption refrigeration system to further cool its heat sink temperature. By using a liquid suitable for refrigeration within the control loop, evaporative cooling can be used for removing heat from the working gas by passing the liquid refrigerant over a heat exchanging surface, causing evaporation to occur and the removal of heat.
[0058] The HOC removed from one pressure vessel's working gas during its compression can be added to the already expanding working of the other pressure vessel to provide additional heat. This can be done by providing that the control loop directs the flow of HOC removed from the first pressure vessel to the second during this part of the cycle. On the return, the opposite can occur as the HOC from the second pressure vessel is directed to the first during its expansion.
[0059] An advantage of the control loop having its heat transfer media in indirect contact with working fluid is that the control loop pressure can remain at low pressure and large inexpensive heat exchangers can be used made of plastic, inexpensive steel, rubber hose etc.
[0060] The engine's versatility allows it to take on may forms including using the tubular frames of vehicles and equipment or flexible hose to function as the high pressure piping and control loops of the engine.
[0061] As mentioned earlier, since the present invention can produce high grade heat from low grade heat using the working gas' HOC generated, and the overal engine efficiency rises as one increases the difference in temperatures between the engine highest and lowest temperatures, then in situations when only a moderate temperature heat source is available we can utilize the high temperatures produced by the engine cycle's HOC to become our max system temperature instead of the lower temperature heat source. This allows us to discard heat at high temperature differentials to the engine's heat sink. The moderate temperature heat from the heat source can then be utilized for providing that heat back to the high pressure working gas that was originally removed in order for it to expand and perform work to sustain the continued operation of the engine. If no work is extracted from the engine and it is simply allowed to rise in temperature and pressure to its maximum operating capabilities, then this would become its maximum operating efficiency. The control loop of the engine can modulate the performance of the engine so that the engine can deliver what is needed at a particular time such as running for peak work output, or running for peak efficiency, or somewhere inbetween.
[0062] Depending on the power stroke of a particular motor used such as piston, rotary etc., will determine whether heat is inputted during expansion all initially or spread out over the course of the expansion so that it is either carnot (isothermal/adiabatic), isothermal, or even something custom such as high initial power output with tapering power at end of stroke.
[0063] One advantage to having a closed system control loop is that it allows the loop to run at high pressure, equal to that of the high pressure working gas enabling thin-walled heat exchangers to be used, facilitating quick and easy heat transfer. A high pressure control loop also suppresses the vaporization of liquid thermal transfer medias that may be used within the loop.
[0064] The high pressure working gas within the high pressure piping helps to suppress the vaporization of the hydraulic piston during operation, even at high temperatures well above their ambient boiling points.
[0065] The high pressure piping can be pre-pressurize with chemical reactions, hydraulic head etc.
[0066] The control loop's thermal transfer media may include a steel ring that can be heated on one side and cooled on the other that as it rotates, moves in an out of heat exchanging contact with the high pressure working gas of the pressure vessels. Similarly, using a metal chain or similar flexible solid rolling through the pressure vessels can also function as a thermal transfer media. Ball bearings flowing down through heat exchanger coils is still another possibility.
[0067] As mentioned earlier using the engine's HOC to increase the operating temperature of the engine to its maximum performance capabilities, during this ramp-up time, no heat is needed to be rejected simply because for short running duration, it is not necessary to have heat dissipation due to the fact that there will temporarily exist a temperature differential between the high pressure working gas of the two pressure vessels allowing cycling to occur between them until their temperatures balance, at which time the engine will no longer cycle.
[0068] The modulation of the engine must be managed by logic controllers as commonly used by HVAC systems.
[0069] The temp rise of the gas being compressed depends on several factors such as gas density (initial pressure), piston speed, heat sink temp, density & capacity, set temp of heat extraction etc. as is well know to those versed in thermodynamics.
[0070] Some of the factors a designer must consider in the design of the engine's control loop depending on its application are as follows: The space available; whether the primary use of the engine is for hydraulic work, heating, cooling or as a heat source for another engine; the pressure and temperature capabilities of the materials used; the heat sink available; what the waste heat will be used for; the distance between the pressure vessels; the type of heat source; the cycle rate desired; the power output/performance desired.
[0071] The engine's temperature control system would have to sense the temperature within the working gas and thermal transfer media within the control loop to then regulate the volume flow of thermal transfer media within the control loop to maintain the temperature of the working gas by opening or closing a valve until the set temperature is maintained.
[0072] Another factor a designer must take into consideration when designing the present invention is the thermal transfer rate of the heat exchangers when timing the cycling of the engine.
[0073] The flow of the hot and cool liquid within the control loop and heat exchangers that subsequently controls the input and removal of heat to the working gas is fully regulated in both directions via the circulation pump, enabling it to speed up, slow down or dwell. This allows for real-time modulation of the engine's compression and power stroke to create an isothermal, adiabatic, or any other condition within the gas, producing any desired power curve or cycle, including the Carnot cycle.
[0074] The embodiment depicted in this application is shown only for the purposes of illustrating the operation of the engine as it pertains to producing power. As with any technology, different applications and varying requirements can cause the engine to take on many different forms and functions and although it would be impossible to capture all of the present and future design options necessary to meet these various applications and requirements, a partial list was provided here for reference. Obviously those skilled and knowledgeable in the art of heat engines, HVAC systems and controls and hydraulics will already have a good foundation for its design. | A high performance modular heat engine is presented that uses a highly pressurized working gas and hydraulic fluid within a pipeline or flow circuit to produce power hydraulically. It does this by adding heat to the working gas via a control loop, isolated from the power producing working gas and hydraulic fluid, to increase its pressure and impart movement to said hydraulic fluid. The heat engine can utilizes its working gas' heat of compression to improve its performance by removing it during compression and returning it to the working gas during expansion. The engine can use momentum developed internally to convert low temperature heat into high temperature heat to boost its efficiency and performance by creating an artificial high ΔT between its heat source and heat sink. | 5 |
BACKGROUND OF THE INVENTION
This invention relates to a color television camera in which the color component signals representing the first and second colors of a color image are reproduced utilizing the difference of modulation phase relationships of the color component signals, at least one of which changes in successive scan lines.
A color television camera of the type employing a single pick-up tube for producing a color video signal by processing successive line signals produced by line scans is shown, for instance, in the U.S. Pat. No. 3,647,943 or Japanese Published Pat. No. 45-8699. In those cameras, the first color of the color image, such as red, is spatially modulated by a first striped color filter so as to have a first phase relationship, such as an in phase relationship, in successive scan lines, and the second color of the color image, such as blue, is spatially modulated by a second striped color filter so as to have a second phase relationship, such as an opposite phase relationship, in successive scan lines. As well known in the art, such a first striped filter may be a W-Ye striped filter disposed perpendicular to the direction of horizontal scanning and containing a plurality of striped filter element pairs, W-elements which are transparent, and Ye-elements which pass red and green light. The second filter may be a W-Cy striped filter disposed at a different angle from the W-Ye striped filter and containing a plurality of striped filter elements, W-elements, and Cy-elements which pass blue and green light.
A modulated component of the composite signal produced by line scans of the pick-up tube is provided to a comb-filter comprising a delay line (1H-delay line) which has a delay time of one horizontal scanning period, an adder and a subtractor, such as shown in FIG. 1, to recover the first and second color component signals. Then the color component signals are combined with a luminance signal derived from the composite signal to produce color difference signals.
In such a color television camera, when the video pattern of the color image has no relationship or even a partial relationship, such as a bar pattern including the vertical edge portions therein, in successive lines of scan, such as shown in FIG. 2A, color errors take place at the edge portions in the reproduced color image on the picture screen of the color television reproducing apparatus. The color error is especially conspicuous when the optical image includes black and white patterns.
Supposing that the n-th horizontal line scan occurs on a block area with a reflectivity of 10% and the (n+1)-th horizontal line scan on a white area with a reflectivity of 90%, the modulated component signals derived from the pick-up tube are expressed by the following equations:
Fn=0.1·{R·sin ωt+B·sin (ωt+φ)}(1)
Fn+1=0.9·{R·sin ωt+B sin (ωt+π+φ)}(2)
where R and B denote the red and blue components respectively, and φdenotes a phase constant determined by the position of the line scans. These signals which appear at the input terminal and the output terminal, respectively, of the delay line (1H-delay line) are added to and substracted from each other in the comb-filter, to produce red component signal Fr and blue component signal F b , respectively, as follows:
Fr=0.5·R·sin ωt-0.4·B·sin (ωt+φ)
Fb=-0.4·R·sin ωt+0.5·B·sin (ωt+φ)
where each coefficient of R or B is converted so that it becomes unity when the video patterns scanned in the successive line scans are correlated to each other.
Therefore, if the ratio R:B equals 1:1, the amplitude of the detected color component signals R(t) and B(t) changes stepwise at such an edge portion, such as shown in FIG. 3. This change in level occurs because the color television camera employed in this system must combine the signals from two successive scans in order to produce the color component signals R(t) and B(t). The average level of the edge portion is half that of the correlated pattern. In contrast, in the luminance signal derived from a low pass filter from the output signal of the pick-up tube, such a change of the level does not occur even at the edge portion. This is because the luminance signal is derived from individual scans without requiring a combination of successive scans. In the television camera employed in this system the color difference signals are produced from the color component signals R(t) and B(t) and the luminance signal Y(t). When two successive scans are uncorrelated or only partially correlated the color component signals R(t) and B(t) produced from those successive scans are based on an artificially averaged video pattern of the two successive scans differing from the real video pattern of either of the two successive scans. As the result, a color error component is carried into the color difference signals at the edge portion of the optical image pattern.
There has been proposed an apparatus for suppressing such color errors in U.S. Pat. No. 4,104,679 issued to Kitamura, one of whose joint inventors is a joint inventor of the present invention. According to the apparatus proposed in U.S. Pat. No. 4,109,679, edge portions are detected by processing the luminance signal, and the detection signal is utilized to control the wave shape of the luminance signal used to reproduce the color signals, the wave shapes of the color component signals derived by the comb-filter, or both. This apparatus is effective when the signal ration R:B is about 1:1 and φ is nearly constant. However, the ratio is not always 1:1, but varies with the color temperature of the light source, the characteristics of each pick-up tube and also with the kind of pick-up tube. Moreover it is difficult to maintain φ constant due to scanning distortion of the vertical deflection device.
SUMMARY OF THE INVENTION
An object of the invention, therefore, is to provide a color television camera in which color error components are suppressed in a process for deriving color component signals from the output signal of a pick-up device.
According to this invention, edge portions in an optical image pattern are detected by processing the unmodulated signal such as the luminance signal to generate a color error correction signal, and the correction signal is utilized to control the amplitude of the modulated component signal so that the color error components are not carried into color component signals.
The above and other objects, features and advantages will become readily apparent from the following description of some practical embodiments of the invention.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a block diagram showing a comb-filter of a color television camera according to the prior art;
FIG. 2A and FIG. 2B are schematic diagrams showing examples of optical image patterns;
FIG. 3 is a set of diagrams of reproduced color component signals and the luminance signal in the color television camera shown in FIG. 1 when the image pattern shown in FIG. 2A is scanned;
FIG. 4 is a block diagram showing the construction of an embodiment of a color television camera according to the invention;
FIG. 5A, FIG. 5B and FIG. 5C are diagrams of the modulated component signals produced in the television camera of FIG. 4 when the optical image pattern of FIG. 2B is scanned;
FIG. 6 is a schematic diagram showing the characteristics of the non-linear circuit 6 of FIG. 4;
FIG. 7 is a circuit diagram showing the construction of the non-linear circuit 6 of FIG. 4;
FIG. 8 is a circuit diagram showing the construction of a gain control circuit of an embodiment of the invention;
FIG. 9 is a schematic diagram showing the characteristics of the gain control circuit of FIG. 8;
FIG. 10 is a block diagram showing the construction of a color correction signal generating circuitry of the another embodiment of the invention;
FIG. 11 is a circuit diagram showing the construction of the non-linear circuit 100 of the embodiment of FIG. 10;
FIG. 12 is a diagram showing the characteristics of the non-linear circuit 10 of FIG. 11.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the embodiment of the invention, shown in FIG. 4, the optical color image is spatially modulated by the W-Ye striped filter and the W-Cy striped filter built into the pick-up tube 1, so that the pick-up tube 1 produces an output signal including the modulated component signal and the unmodulated component signal in the same manner as the abovedescribed color television camera. The output signal from the pick-up tube 1 is amplified by a pre-amplifier 2 then supplied to a low-pass filter 3 which removes the modulated component to produce the luminance signal Y(t). The output signal from the pre-amplifier 2 is also supplied to a band-pass filter 4 which derives the modulated component signal from the output signal, and to a trap circuit 5 which removes the modulated component signal in the same manner as the low-pass filter 3. The output of the trap circuit 5, which represents the luminance of the color image, is supplied to color correction signal generating circuitry 40 which detects the portions in which the image has no correlation in successive scan lines and generates a color error correction signal by operating upon adjacent lines of signals. In this embodiment the circuitry 40 consists of a non-linear circuit 6 having a logarithmic input-to-output characteristic, a delay line 7 delaying the output of the non-linear circuit 6 by one horizontal scanning period, and a subtract circuit 8 subtracting the output of the delay line 7 from the output of the non-linear circuit 6 to generate the color error correction signal.
The modulated component signal from the band-pass filter 4 is delayed by one horizontal scanning period by a delay line 9 then supplied through a gain control circuit 10 to an add circuit 11 and a subtract circuit 12, both of which are also supplied with the output of bass-pass filter 4. The delay line 9, the add circuit 11 and the subtract circuit 12 constitute a comb-filter such as shown in FIG. 1. Color component signals R(t) and B(t) are derived from detectors 13 and 14 by detecting the outputs from the add circuit 11 and the subtract circuit 12, respectively.
The gain control circuit 10 controls the amplitude of the delayed modulated component signal in accordance with the color error correction signal, so that the color error components are suppressed in the outputs of the add circuit 11 and the subtract circuit 12. In this case the gain control circuit has exponential characteristics with respect to the color correction signal.
For instance, if the modulated component signal is given by the equations (1) and (2) in successive scan lines the gain control circuit amplifies the delayed signal by nine times so that the output thereof is expressed as:
F.sub.n =0.9·{R·sin ωt+B·sin (ωt+φ)}.
Since F n and F n+1 are operated upon in the add circuit 11 and the subtract circuit 12, the modulated color component signals Fr and Fb can be expressed by following equations, in which the color error components are cancelled.
Fr=0.9·R·sin ωt
Fb=0.9·B·sin (ωt+φ)
The detected color component signals R(t) and B(t) from the detectors 13 and 14 are provided to an encoder 15 along with the luminance signal Y(t) from the low-pass filter 3 to produce a color video signal, such as the NTSC signal.
When the n-th horizontal line scan occurs on an area in which the reflectivity of the image changes in the sequence 10%-50%-90% in the horizontal direction, and (n+1)-th horizontal scan occurs on an area in which the reflectivity is 90%, such as shown in FIG. 2B, the amplitudes of the modulated component signals F n and F n+ 1 are such as shown in FIG. 5A. As is obvious from these figures the modulated component signal F n includes a first portion I, a second portion II and third portion III with a reflectivity of 10%, 50% and 90%, respectively. In this case the modulated component signal F n from the delay line 9 requires amplification by gain control circuit 10 by nine times during the first portion and nine fifth times during the second portion in order to prevent color error components both in the add circuit 11 and the subtract circuit 12. Similarly, when the reflectivity during the (n+1)-th horizontal line scan is 50%, the signal Fn requires amplification by five times during the first portion and attenuation to five ninths thereof during the third portion in order to prevent color error components in the color component signals, such as shown in FIG. 5B. When the reflectivity during the (n+1)-th horizontal line scan is 10% the signal F n requires attenuation to one fifth thereof during the second portion and one ninth thereof during the third portion, such as shown in FIG. 5C. Such amplification and attenuation are accomplished by the gain control circuit 10 in accordance with the color error correction signal produced by the subtract circuit 8.
FIG. 6 indicates the characteristics of the non-linear circuit 6 and FIG. 7 illustrates the circuit diagram thereof. In FIG. 7, numerals 70, 74, 75 and 76 represent resistances, 71, 72 and 73 represent diodes and E 1 , E 2 and E 3 represent d-c voltage sources. In accordance with the logarithmic characteristics of FIG. 6, the unmodulated component signal from the trap circuit 5 is attenuated in proportion to the increase in amplitude. The output C from the subtract circuit 8, therefore the color error correction signal, is expressed as:
C=log Y.sub.n+1 -log Y.sub.n
=log Y.sub.n+1 /Y.sub.n
where Y n+1 and Y n represent the unmodulated component signals which are derived from the trap circuit 5 by the (n+1)-th and n-th horizontal line scans, respectively.
If the image is black and white or of similar color content, the ratio Y n+ 1 :Y n equals or nearly equals the ratio |F n+1 |:|F n |. Since the gain of the gain control circuit 10 changes in accordance with the exponential characteristic thereof with respect to the color error correction signal, the amplitude of the modulated component signal from the delay line 9 must be multiplied by |F n+1 |/|F n | to be equal to that of the undelayed modulated component signal from the band-pass filter 4. As the result, no color error components appear in the outputs of the add circuit 11 and the subtract circuit 12. By removing the color errors which may occur more conspicuously in the black and white pattern and the color constant patterns, the quality of the reproduced image on the picture screen is greatly improved.
FIG. 8 illustrates the circuit diagram of the gain control circuit 10 according to this embodiment of the invention, which consists essentially of a differential amplifier. In FIG. 8 the modulated component signal from the delay line 10 is provided through an input terminal 80 to the base electrode of a transistor 83 the collector electrode of which is connected to the common emitter electrodes of transistors 84 and 85. An output terminal 82 is connected to the junction point of a load resistance 86 and the collector electrode of the transistor 85 through a band-pass filter 87.
As is known, the gain of such a differential amplifier is controlled by a control signal which is supplied to the base electrode of the transistor 84 through a control terminal 81. The characteristics of the differential amplifier is shown in FIG. 9. The control signal, in this case, is the color error correction signal from the color correction signal generating circuitry and the operating point of the differential amplifier is set by the bias resistances 88 to make full use of the controllable range of the gain control circuit. It is obvious from FIG. 9, that the gain of circuit changes linearly in proportion to the control signal. Therefore the amplitude of the color error correction signal should be different in the amplification mode and than in the attenuation mode of the amplifier even if ratios of amplification and the attenuation are the same.
The color correction signal generating circuitry required for this embodiment, therefore, further comprises a non-linear circuit 100 coupled between the subtract circuit 8 and the gain control circuit 10, such as shown in FIG. 10. The construction and the input-to-output characteristics thereof are illustrated in FIG. 11 and FIG. 12, respectively. In FIG. 11, the output signal from the subtract circuit 8 the quiescent level of which signal is clamped at a reference voltage such as zero volts is supplied to germanium diodes 101 and 102 and a silicon diode 103. The negative portion of the signal is attenuated by the germanium diode 101 and a pre-set variable resistance 104 with respect to the positive portion. The gradient and the shape of the curve representing the characteristics of FIG. 12 are adjusted by the pre-set resistance 104, a fixed resistance 105 and the diodes 101, 102 and 103. If necessary an additional non-linear circuit having an exponential input-to-output characteristic is connected between the subtract circuit 8 and the gain control circuit 10 in series with the non-linear circuit 100.
Though in the above described embodiment the gain control circuit is coupled between the delay line 9 and the operating circuits 11 and 12, it may be connected between the band-pass filter 4 and the delay line 9. It is also possible to connect the gain control circuit between the band-pass filter 4 and the operating circuits 11 and 12 in parallel with the delay line 9. In the latter case the gain control circuit must control the amplitude of the modulated component signal F n+1 to be equal to that of the modulated component signal F n .
Although this invention has been particularly shown and described, it is contemplated that various changes and modifications may be made without departing in any way from the scope of the invention as set forth in the following claims. | The present invention is a color television camera employing a single pick-up tube and producing color component signals utilizing a difference of phase relationships of the modulated color signals, at least one of which changes in successive horizontal scan lines. In such a color television camera, the amplitude of a modulated component signal is controlled by a color error correction signal which is produced from the unmodulated component signals derived from adjacent horizontal line scans, so that color error components are not carried into the color component signals. | 7 |
This application is a continuation of U.S. patent application Ser. No. 14/623,730, filed Feb. 17, 2015, now U.S. Pat. No. 9,228,327, which is a continuation of U.S. patent application Ser. No. 13/048,445, filed Mar. 15, 2011, now U.S. Pat. No. 8,474,476, which claims the benefit of U.S. Provisional Patent Application Ser. No. 61/313,902, filed Mar. 15, 2010, and U.S. Provisional Patent Application Ser. No. 61/313,918, filed Mar. 15, 2010, the entire disclosures of which are incorporated by reference herein.
This application is also related to U.S. Pat. No. 8,042,565, U.S. Pat. No. 7,472,718, and U.S. Pat. No. 7,730,901, the entire disclosures of which are incorporated by reference herein.
FIELD OF THE INVENTION
Embodiments of the present invention are generally related to contamination proof hydrants that employ a venturi that facilitates transfer of fluid from a self-contained water storage reservoir.
BACKGROUND OF THE INVENTION
Hydrants typically comprise a head interconnected to a water source by way of a vertically oriented standpipe that is buried in the ground or interconnected to a fixed structure, such as a roof. To be considered “freeze proof” hydrant water previously flowing through the standpipe must be directed away from the hydrant after shut off. Thus many ground hydrants 2 currently in use allow water to escape from the standpipe 6 from a drain port 10 located below the “frost line” 14 as shown in FIG. 1 .
Hydrants are commonly used to supply water to livestock that will urinate and defecate in areas adjacent to the hydrant. It follows that the animal waste will leach into the ground. Thus a concern with freeze proof hydrants is that they may allow contaminated ground water to penetrate the hydrant through the drain port when the hydrant is shut off. More specifically, if a vacuum, i.e., negative pressure, is present in the water supply, contaminated ground water could be drawn into the standpipe and the associated water supply line. Contaminants could also enter the system if pressure of the ground water increases. To address the potential contamination issue, “sanitary” yard hydrants have been developed that employ a reservoir that receives water from the standpipe after hydrant shut off.
There is a balance between providing a freeze proof hydrant and a sanitary hydrant that is often difficult to address. More specifically, the water stored in the reservoir of a sanitary hydrant could freeze which can result in hydrant damage or malfunction. To address this issue, attempts have been made to ensure that the reservoir is positioned below the frost line or located in an area that is not susceptible to freezing. These measures do not address the freezing issue when water is not completely evacuated from the standpipe. That is, if the reservoir is not adequately evacuated when the hydrant is turned on, the water remaining in the reservoir will effectively prevent standpipe water evacuation when the hydrant is shut off, which will leave water above the frost line.
To help ensure that all water is evacuated from the reservoir, some hydrants employ a venturi system. A venturi comprises a nozzle and a decreased diameter throat. When fluid flows through the venturi a pressure drop occurs at the throat that is used to suction water from the reservoir. That is, the venturi is used to create an area of low pressure in the fluid inlet line of the hydrant that pulls the fluid from the reservoir when fluid flow is initiated. Sanitary hydrants that employ venturis must comply with ASSE-1057, ASSE-0100, and ASSE-0152 that require that a vacuum breaker or a backflow preventer be associated with the hydrant outlet to counteract negative pressure in the hydrant that may occur when the water supply pressure drops from time-to-time which could draw potentially contaminated fluid into the hydrant after shut off. Internal flow obstructions associated with the vacuum breakers and backflow preventers will create a back pressure that will affect fluid flow through the hydrant. More specifically, common vacuum breakers and backflow preventers employ at least one spring-biased check valve. When the hydrant is turned on spring forces are counteracted and the valve is opened by the pressure of the fluid supply, which negatively influences fluid flow through the hydrant. In addition an elongated standpipe will affect fluid flow. These sources of back pressure influence flow through the venturi to such a degree that a pressure drop sufficient to remove the stored water from the reservoir will not be created. Thus to provide fluid flow at a velocity required for proper functioning of the venturi, fluid diverters or selectively detachable backflow preventers, i.e., those having a quick disconnect capability, have been used to avoid the back pressure associated with the vacuum breakers of backflow preventers. In operation, as shown in FIG. 2 , the diverter is used initially for about 45 seconds to ensure reservoir evacuation. Then, the diverter is disengaged so that the water will flow through the backflow preventer or vacuum breaker. The obvious drawback of this solution is that the diverter must be manually actuated and the user must allow water to flow for a given amount of time, which is wasteful.
Further, as the standpipe gets longer it will create more backpressure, i.e., head pressure, that reduces the flow of water through the venturi, and at some point a venturi of any design will be unable to evacuate the water in the reservoir. That is, the amount of time it takes for a hydrant to evacuate the water into the reservoir depends on the height/length of the standpipe as well as the water pressure. The evacuation time of roof hydrants of embodiments of the present invention, which has a 42″ standpipe, is 5 seconds at 60 psi. The evacuation time will increase with a lower supply pressure or increased standpipe length or diameter. Currently existing hydrants have evacuation times in the 30 second range.
Another way to address the fluid flow problem caused by vacuum breakers is to provide a reservoir with a “pressure system” that is capable of holding a pressure vacuum that is used to suction water from the standpipe after hydrant shut off. During normal use the venturi will evacuate at least a portion of the fluid from the reservoir. Supply water is also allowed to enter the reservoir which will pressurize any air in the reservoir that entered the reservoir when the reservoir was at least partially evacuated. When flow through the hydrant is stopped, the supply pressure is cut off and the air in the reservoir expands to created a pressure drop that suctions water from the standpipe into the reservoir. If the vacuum produced is insufficient, which would be attributed to incomplete evacuation of the reservoir, water from the standpipe will not drain into the reservoir and water will be left above the frost line.
Other hydrants employ a series of check valves to prevent water from entering the reservoir during normal operations. Hydrants that employ a “check system” uses a check valve to allow water into or out of the reservoir. When the hydrant is turned on, the check valve opens to allow the water to be suctioned from the reservoir. The check also prevents supply water from flowing into the reservoir during normal operations, which occurs during the operation of the pressure vacuum system. When the hydrant is shut off, the check valve opens to allow the standpipe water to drain into the reservoir. One disadvantage of a check system is that it requires a large diameter reservoir to accommodate the check valve. Thus a roof hydrant would require a larger roof penetration and a larger hydrant mounting system, which may not be desirable.
Another issue associated with both the pressure vacuum and check systems is that there must be a passageway or vent that allows air into the reservoir so that when a hydrant is turned on, the water stored in the reservoir can be evacuated. If the reservoir was not exposed to atmosphere, the venturi would not create sufficient suction to overcome the vacuum that is created in the reservoir.
SUMMARY OF THE INVENTION
It is one aspect of embodiments of the present invention to provide a sanitary and freeze proof hydrant that employs a venturi for suctioning fluid from a fluid storage reservoir. As one of skill in the art will appreciate, the amount of suction produced by the venturi is a function of geometry. More specifically, the contemplated venturi is comprised of a nozzle with an associated throat. Water traveling through the nozzle creates an area of low pressure at or near the throat that is in fluid communication with the reservoir. In one embodiment, the configuration of the nozzle and throat differs from existing products. That is, the contemplated nozzle is configured such that the venturi will operate in conjunction with a vacuum breaker, a double check backflow preventer, or a double check backflow prevention device as disclosed in U.S. Patent Application Publication No. 2009/0288722, which is incorporated by reference in its entirety herein, without the need for a diverter. Preferably, embodiments of the present invention are used in conjunction with the double check backflow prevention device of the '722 publication as it is less disruptive to fluid flow than the backflow preventers and vacuum breakers of the prior art.
While the use of a venturi is not new to the sanitary yard hydrant industry, the design features of the venturi employed by embodiments of the present invention are unique in the way freeze protection is provided. More specifically, current hydrants employ a system that allows water to bypass a required vacuum breaker. For example, the Hoeptner Freeze Flow Hydrant employs a detachable vacuum breaker and the Woodford Model S3 employs a diverter. Again, fluid diversion is needed so that sufficient fluid flow is achieved for proper venturi functions. The venturi design of sanitary hydrants of the present invention is unique in that the venturi will function properly when water flows through the vacuum breaker or double check backflow preventer—no fluid diversion at the hydrant head is required. This allows the hydrant to work in a way that is far more user friendly, because the hydrant is able to maintain its freeze resistant functionality without requiring the user to open a diverter, for example. Embodiments of the present invention are also environmentally friendly as resources are conserved by avoiding flowing water out of a diverter.
It is another aspect of the embodiments of the invention is to provide a hydrant that operates at pressures from about 20 psi to 125 psi and achieves a mass flow rate above 3 gallons per minute (GPM) at 25 psi, which is required by code. One difficult part of optimizing the flow characteristics to achieve these results is determining the nozzle diameter. It was found that a throat diameter change of about 0.040 inches would increase the mass flow rate by 2 GPM. That same change, however, affects the operation of the venturi. For example, hydrants with a nozzle diameter of 0.125 inches will provide acceptable reservoir evacuation but would not have the desired mass flow rate. A 0.147 inch diameter nozzle will provide an acceptable mass flow rate, but reservoir evacuation time was sacrificed. In one embodiment of the present invention a venturi having a nozzle diameter of about 0.160 inches is employed.
It is another aspect of the present invention to provide a nozzle having an exit angle that facilitates fluid flow through the venturi. More specifically, the nozzle exit of one embodiment possesses a gradual angle so that fluid flowing through the venturi maintains fluid contact with the surface of the nozzle and laminar flow is generally achieved. In one embodiment the exit angle is between about 4 to about 5.6 degrees. For example, nozzle exit having very gradual surface angle, e.g. 1-2 degrees, will evacuate the reservoir more quickly, but would require an elongated venturi. Thus, an elongated venturi may be used to reduce back pressure associated with the venturi, but doing so will add cost. The nozzle inlet may have an angle that is distinct from that of the exit to facilitate construction of the venturi by improving the machining process.
It is thus one aspect of the present invention to provide a sanitary hydrant, comprising: a standpipe having a first end and a second end; a head for delivering fluid interconnected to said first end of said standpipe; a fluid reservoir associated with said second end of said standpipe; a venturi positioned within said reservoir and interconnected to said second end of said standpipe, said venturi comprised of a first end, which is interconnected to said standpipe, and a second end associated with a fluid inlet valve with a throat between said first end and said second end of said venturi; a bypass tube having a first end interconnected to a location adjacent to said first end of said venturi and a second end interconnected to a bypass valve, said bypass valve also associated with said second end of said venturi, wherein when said bypass valve is opened, fluid flows from said inlet valve, through said bypass tube, through said standpipe, and out said hydrant head; and wherein when said bypass valve is closed, fluid flows through said venturi, thereby creating a pressure drop adjacent to said throat that communicates with said reservoir to draw fluid therefrom.
It is another aspect to provide a method of evacuating a sanitary hydrant, comprising: providing a standpipe having a first end and a second end; providing a head for delivering fluid interconnected to said first end of said standpipe; providing a fluid reservoir associated with said second end of said standpipe; providing a venturi positioned within said reservoir and interconnected to said second end of said standpipe, said venturi comprised of a first end, which is interconnected to said standpipe, and a second end associated with a fluid inlet valve with a throat between said first end and said second end of said venturi; providing a bypass tube having a first end interconnected to a location adjacent to said first end of said venturi and a second end interconnected to a bypass valve, said bypass valve also associated with said second end of said venturi, wherein when said bypass valve is opened, fluid flows from said inlet valve, through said bypass tube, through said standpipe, and out said hydrant head; and wherein when said bypass valve is closed, fluid flows through said venturi, thereby creating a pressure drop adjacent to said throat that communicates with said reservoir to draw fluid therefrom initiating fluid flow through said head by actuating a handle associated therewith; actuating a bypass button that opens the bypass valve such that fluid is precluded from entering said venturi; actuating said bypass button to close said bypass valve; flowing fluid through said venturi; evacuating said reservoir; ceasing fluid flow through said hydrant; and draining fluid into said reservoir.
The Summary of the Invention is neither intended nor should it be construed as being representative of the full extent and scope of the present invention. Moreover, references made herein to “the present invention” or aspects thereof should be understood to mean certain embodiments of the present invention and should not necessarily be construed as limiting all embodiments to a particular description. The present invention is set forth in various levels of detail in the Summary of the Invention as well as in the attached drawings and the Detailed Description of the Invention and no limitation as to the scope of the present invention is intended by either the inclusion or non-inclusion of elements, components, etc. in this Summary of the Invention. Additional aspects of the present invention will become more readily apparent from the Detail Description, particularly when taken together with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and together with the general description of the invention given above and the detailed description of the drawings given below, serve to explain the principles of these inventions.
FIGS. 1A-1C are a depiction of the operation of a hydrant of the prior art;
FIGS. 2A-2C are a series of figures depicting the use of a flow diverter of the prior art;
FIG. 3 is a cross section of a venturi of the prior art;
FIG. 4 is a perspective view of a venturi system employed by the prior art;
FIG. 5 is a perspective view of one embodiment of the present invention;
FIG. 6 is a detailed view of the venturi system of the embodiment of FIG. 5 ;
FIG. 7 is a perspective view similar to that of FIG. 6 wherein the reservoir has been omitted for clarity;
FIG. 8 is a cross sectional view of a venturi system that employs a bypass tube of one embodiment of the present invention;
FIG. 9 is a cross sectional view of a bypass valve used in conjunction with the embodiment of FIG. 5 shown in an open position;
FIG. 10 shows the bypass valve of FIG. 9 in a closed position;
FIG. 11 is a top perspective view of one embodiment of the present invention showing a bypass button and an electronic reservoir evacuation button;
FIG. 12 is a graph showing sanitary hydrant comparisons;
FIG. 13 is a perspective view of a venturi system of another embodiment of the present invention;
FIG. 14 is a detailed cross sectional view of FIG. 13 showing the check valve in a closed position when the hydrant is on;
FIG. 15 is a detailed cross sectional view of FIG. 13 showing the check valve in an open position when the hydrant is off;
FIG. 16 is a cross sectional view showing a hydrant of another embodiment of the present invention;
FIG. 17 is a detail view of FIG. 16 ;
FIG. 18 is a detail view of FIG. 17
FIG. 19 is a cross section of another embodiment of the present invention; and
FIG. 20 is a table showing a comparison of various hydrant assemblies and the operation cycle of each.
It should be understood that the drawings are not necessarily to scale, but that relative dimensions nevertheless can be determined thereby. In certain instances, details that are not necessary for an understanding of the invention or that render other details difficult to perceive may have been omitted. It should be understood, of course, that the invention is not necessarily limited to the particular embodiments illustrated herein.
To assist in the understanding of one embodiment of the present invention the following list of components and associated numbering found in the drawings is provided herein:
#
Component
2
Hydrant
4
Head
5
Handle
6
Standpipe
10
Drain port
14
Frost line
18
Venturi
22
Diverter
26
Vacuum breaker
30
Siphon tube
34
Check valve
36
Outlet
37
Venturi vacuum inlet and drain port
38
Hydrant inlet valve
42
Bypass
46
Bypass button
50
Casing cover
54
Piston
56
Bypass valve
57
Control rod
58
Secondary spring operated piston
59
Bottom surface
60
EFR button
64
LED
68
Screen piston
72
Reservoir
76
Check valve piston
80
Vent
DETAILED DESCRIPTION
The venturi 18 and related components used in the hydrants of the prior art is shown in FIGS. 3 and 4 and functions when the hydrant issued in conjunction with a vacuum breaker and a diverter. The diverter is needed to allow the venturi to work properly in light of the flow obstructions associated with the vacuum breaker. A typical on/off cycle for this hydrant (see also FIG. 2 ) requires that the user open the hydrant to cause water to exit the diverter 22 and not the vacuum breaker 26 . As the water flows out of the diverter 22 , a vacuum is created that draws water through a siphon tube 30 and check valve 34 , which evacuates the reservoir (not shown). Flowing water through the diverter 22 for about 30 to 45 seconds will generally evacuate the reservoir. Next, as shown in FIG. 2 , the diverter 22 is pulled down to redirect the water out of the vacuum breaker 26 . The vacuum breaker 26 allows the hydrant 2 to be used with an attached hose and/or a spray nozzle as the vacuum breaker 26 will evacuate the head when the hydrant 2 is shut off, thereby making it frost proof. When the water is flowing out of the vacuum breaker 26 the venturi 18 will stop working and the one-way check valve 34 will prevent water from entering the reservoir. Once the hydrant is shut off, the water in the standpipe 6 will drain through a venturi vacuum inlet and drain port 37 that is in fluid communication with the reservoir similar to that disclosed in U.S. Pat. No. 5,246,028 to Vandepas, which is incorporated by reference herein. The check valve 34 is also pressurized when the hydrant is turned off because the shut off valve 38 is located above the check valve 34 .
A venturi assembly used in other hydrants that employ a pressurized reservoir also provides a vacuum only when water flows through a diverter. A typical on/off cycle for a hydrant that uses this venturi configuration is similar to that described above, the exception being that a check valve that prevents water from entering the reservoir is not used. When the diverter is transitioned so water flows through the vacuum breaker, the backpressure created thereby will cause water to fill and pressurize the reservoir, which prevents water ingress after hydrant shut off. As the reservoir is at least partially filled with water during normal use, the user needs to evacuate the hydrant after shut off by removing any interconnected hose and diverting fluid for about 30 seconds, which will allow the venturi to evacuate the water from the reservoir.
A hydrant of embodiments of the present invention shown in FIGS. 5-11 which may employ a venturi with an about ⅛″ diameter nozzle. To account for the decrease in mass flow and associated back pressure that affects the functionality of the venturi described above, a bypass 42 is employed. More specifically, the bypass 42 maintains the flow rate out of the hydrant head 4 and allows for water to be expelled from the head 4 at the expected velocity. Fluid bypass is triggered by actuating a button 46 located on the casing cover 50 as shown in FIG. 11 . When the hydrant is turned on the user pushes the bypass button 46 that will in turn move a bypass piston 54 of a bypass valve 56 into the open position as shown in FIG. 9 . This will allow water to bypass the venturi 2 and re-enter the standpipe above the restriction caused by the venturi. The increased flow rate is greater than could be achieved with a venturi alone, even if the diameter of the venturi nozzle was increased.
While the bypass allows the mass flow rate to increase greatly, it also causes the venturi to stop creating a vacuum that is needed to evacuate the reservoir. Before normal use, the bypass piston 54 is closed as shown in FIG. 10 . Similar to the system described in FIG. 16 below, the venturi 18 and associated bypass 42 are associated with a control rod 57 that is associated with the hydrant handle 5 . Opening of the hydrant transitions the control rod 57 upwardly, which pulls the venturi 18 and associated bypass 42 upwardly and opens the hydrant inlet valve 38 to initiate fluid flow. Conversely, transitioning the hydrant handle 5 to a closed position will move the venturi 18 and associated bypass 42 downwardly such that a secondary spring operated piston 58 of the bypass valve 56 well contact a bottom surface 59 of the reservoir. As the secondary spring piston 58 contacts the bottom surface 59 , the bypass valve 54 moves to a closed position as shown in FIG. 10 . Moving the handle 5 to an open position to initiate fluid flow through the hydrant head will separate the secondary spring operated piston 58 from the bottom surface 59 of the reservoir which allows the bypass piston 54 to move to an open position as shown in FIG. 9 when the bypass button 46 is actuated. When the bypass 42 is in the closed position, water is forced to flow through the venturi causing a vacuum to occur, thereby causing the reservoir to be evacuated each time the hydrant is used. After water flows from the vacuum breaker for a predetermined time, the user will actuate the bypass button 46 which opens the bypass valve 56 to divert fluid around the venturi 2 . The secondary spring operated piston 58 , which is designed to account for tolerances making assembly of the hydrant easier. The secondary spring operated piston 58 also makes sure the hydrant will operate properly if there are any rocks or debris present in the hydrant reservoir.
The venturi 18 of this embodiment can be operated in a 7′ bury hydrant with a minimum operating pressure of 25 psi. The other major exception is the addition of the aforementioned bypass valve 56 that allows the hydrant to achieve higher flow rates.
In operation with a hose, initially the hose is attached to the backflow preventer 26 or the bypass button is pushed to that the venturi will not operate correctly and the one way check valve 34 will be pressurized in such a way to prevent flow of fluid from the reservoir. After the hydrant is shut off, the hose is removed from vacuum breaker 26 . Next the hydrant 2 is turned on and water flows through the vacuum breaker 26 for about 30 seconds. When there is no hose attached, and the bypass has not been activated, the venturi 18 will create a vacuum that suctions water from the reservoir 72 and making the hydrant frost proof. Thus when the hydrant is later shut off, the check valve piston will move up and force open the one way check valve 37 to allow water in the hydrant to drain into the reservoir. This operation will also reset the bypass valve 56 into the closed position.
Some embodiments of the present invention will also be equipped with an Electronic Freeze Recognition (EFR) device as shown in FIG. 11 . The EFR includes a button 60 that allows the user to ascertain if the water has been evacuated from the standpipe 6 properly and if the hydrant is ready for freezing weather. The device uses a circuit board in concert with a dual color LED 64 as shown in FIG. 11 to warn the operator of a potential freezing problem. When the EFR button 60 is pushed and the LED 64 glows red it indicates that the hydrant has not been evacuated properly. This informs the operator that the water in the reservoir is above the frost line, and the hydrant needs to be evacuated by the method described above. A green LED 64 indicates the hydrant has been operated properly and the hydrant is ready for freezing weather.
Flow rates for hydrants of embodiments of the present invention compare favorably with existing sanitary hydrants on the market, see FIG. 12 . The prior art models are compared with hydrants that use a vacuum breaker and hydrants that use a double check backflow preventer. The venturi and related bypass system will meet ASSE 1057 specifications.
Another embodiment of the present invention is shown in FIGS. 13-15 that does not employ a bypass. Variations of this embodiment employ an about 0.147 to an about 0.160 diameter nozzle, which allows for a flow rate of 3 gallons per minute at 25 psi and evacuation of the reservoir at 20 psi. As this configuration meets the desired mass flow characteristics, a bypass is not required to obtain the mass flow rate, and therefore this hydrant can be produced at a lower cost. This embodiment also employs a dual-use check valve. The check valve is closed by a spring when the hydrant is turned on as shown in FIG. 14 to prevent water from filling the reservoir. Again, when water is flowing through the double check backflow preventer a suction can still be produced to pull water from the reservoir through this check valve. When the hydrant is turned off, a screen piston 68 moves up when it contacts the bottom surface 59 of the reservoir which forces the check valve 34 into the open position as shown in FIG. 15 . This allows the water in the hydrant to drain into the reservoir, thereby making the hydrant freeze resistant. Other embodiments of the present invention employ a venturi to evacuate a reservoir, but do not need a diverter to operate correctly. More specifically, a venturi is provided that will evacuate a reservoir through a double check backflow preventer.
FIGS. 16-18 show a hydrant of another embodiment of the present invention that is simpler and more user friendly than sanitary hydrants currently in use. This hydrant is limited to a 5′ bury depth and a minimum working pressure of about 40 psi, which maximizes the venturi flow rate potential, while still being able to evacuate the reservoir as water flows through a double check. A one-way check valve 34 is provided that is forced open when the hydrant is shut off as shown in FIG. 17 .
In operation, this venturi system operates similar to those described above with respect to FIGS. 5-11 . More specifically, the venturi is interconnected to a movable control rod 57 that is located within the standpipe 6 . The handle 5 of the hydrant is thus ultimately interconnected to the venturi 18 and by way of the control rod 57 . To turn on the hydrant, the user moves the handle 5 to an open position, which pulls the control rod 57 upwardly and opens the inlet valve 38 such that water can enter the venturi 18 . Pulling the venturi upward also removes the check valve 34 upwardly such that the screen piston 68 moves away from the bottom surface 59 of the hydrant 2 . To turn the hydrant off, the handle 5 is moved to a closed position which moves the control rod 57 downwardly to move the venturi 18 downwardly to close the inlet valve 38 . Moving the venturi downwardly also transitions the screen piston 68 which opens the check valve 34 . To allow for evacuation reservoir a vent 80 may be provided on an upper surface of the hydrant.
Generally, this hydrant functions when a hose is attached to the backflow preventer. When the hose is attached, the venturi will not operate correctly and the pressure acting on the one way check valve 34 will prevent water ingress into the reservoir 72 . After the hydrant is shut off, the hose is removed from vacuum breaker, the hydrant must be turned on so that the water can flow through the double check vacuum preventer for about 15 seconds. That is, when there is no hose attached, the venturi will create a vacuum sufficient enough to suction water from the reservoir 72 , and making the hydrant frost proof. When the hydrant is later shut off, the check valve piston 26 will move up and force the one way check valve to an open position which allows the water in the hydrant to drain into the reservoir 72 .
FIG. 19 shows yet another hydrant of embodiments of the present invention that is designed specifically for mild climate use (under 2′ bury) and roof hydrants. The outer pipe of the roof hydrant is a smaller 1½ diameter PVC, instead of the 3″ used in some of the embodiments described above. This hydrant uses a venturi without a check valve in concert with a pressurized reservoir, a diverter is not used. The operation is the same as described above with respect to hydrant with a pressurized reservoir, with the evacuation of the reservoir being completed after the user detaches the hose.
FIG. 20 is a table comparing the embodiments of the present invention, which employ an improved venturi of that employ a bypass system, with hydrants of the prior art manufactured by the Assignee of the instant application. The embodiment shown in FIG. 7 , for example, provides an increased flow rate, has an increased bury depth, and can operate at lower fluid inlet pressures. The evacuation time is discussed over the prior art.
While various embodiments of the present invention have been described in detail, it is apparent that modifications and alterations of those embodiments will occur to those skilled in the art. However, it is to be expressly understood that such modifications and alterations are within the scope and spirit of the present invention, as set forth in the following claims. Further, the invention(s) described herein is capable of other embodiments and of being practiced or of being carried out in various ways. In addition, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. For example, aspects of inventions disclosed in U.S. Pat. Nos. 5,632,303, 5,590,679, 7,100,637, 5,813,428, and 20060196561, all of which are incorporated herein by this reference, which generally concern backflow prevention, may be incorporated into embodiments of the present invention. Aspects of inventions disclosed in U.S. Pat. Nos. 5,701,925 and 5,246,028, all of which are incorporated herein by this reference, which generally concern sanitary hydrants, may be incorporated into embodiments of the present invention. Aspects of inventions disclosed in U.S. Pat. Nos. 6,532,986, 6,805,154, 6,135,359, 6,769,446, 6,830,063, RE39235, 6,206,039, 6,883,534, 6,857,442 and 6,142,172, all of which are incorporated herein by this reference, which generally concern freeze-proof hydrants, may be incorporated into embodiments of the present invention. Aspects of inventions disclosed in U.S. Patent and Published Patent Application Nos. D521113, D470915, 7,234,732, 7,059,937, 6,679,473, 6,431,204, 7,111,875, D482431, 6,631,623, 6,948,518, 6,948,509, 20070044840, 20070044838, 20070039649, 20060254647 and 20060108804, all of which are incorporated herein by this reference, which generally concern general hydrant technology, may be incorporated into embodiments of the present invention. | A freeze resistant sanitary hydrant is provided that employs a reservoir for storage of fluid under the frost line or in an area not prone to freezing. To evacuate this reservoir, a means for altering pressure is provided that is able to function in hydrant systems that employ a vacuum breaker. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a control system for controlling the rotational speeds of wheels in automotive vehicles and, more particularly, to the control system such as, for example, anti-lock controllers and traction controllers designed to control braking forces or driving forces applied to wheels that avoid excessive increases in the absolute value of the difference between the wheel rotational speeds and the vehicle running speed, or the appropriately inferred or representative value thereof.
2. Background Information
The prior art wheel speed control system, which is employed, for example, in an anti-lock controller or a traction controller, generally makes two decisions: a decision to determine if the absolute value of the degree of acceleration of the wheel rotational speeds has exceeded a certain limit; and a decision to determine if the absolute value of the difference between the wheel rotational speeds and the vehicle running speed has exceeded a certain limit.
According to the prior art wheel speed control system, when a slightly excessive braking force or a slightly excessive driving force is applied continuously while driving on a road, the frictional force between the wheel tires and the road surface is excessively small, such as when driving on a slippery road due to the presence of, for example, ice. During this time, the absolute value of the difference between the wheel rotational speeds and the vehicle running speed increases only moderately, resulting in a delay of the detection of slip or skid.
More specifically, where the absolute value of the wheel acceleration is zero or very small, the slip or skid cannot be detected unless the absolute value of the difference exceeds a threshold value. When noise components contained in the wheel rotational speeds are taken into consideration, the above-mentioned threshold value cannot be reduced.
Although this problem would bring about relatively little harm in practice in the case of the anti-lock controller because the slightly excessive braking force will not be applied continuously for a prolonged time, this problem cannot be neglected in the case of the traction controller.
SUMMARY OF THE INVENTION
The present invention, in addition to the conventionally employed criterion for decision which uses a first control means previously described, uses an integrating element or a second control means for detecting a moderate increase of the absolute value of the difference between the wheel rotational speeds and the vehicle running speed.
The integrating element uses an index representative of, for example, the absolute value of the difference increasing over a predetermined threshold value for a time greater than a predetermined time, or representative of, for example, the situation in which the balance between the time during which the absolute value of the difference exceeds the threshold value and the time during which it does not exceed prolongs a predetermined time.
The integrating element for the detection of the moderate variation is applicable in any field of technology of the wheel speed control system. It can be used in the field of anti-lock control for relieving the braking force to suppress excessive braking forces and in the field of traction control when applying braking forces to suppress excessive driving forces or relieving the driving force of a prime mover. The integrating element can bring about outstanding effects particularly when applied to traction control, specifically to the control for applying the braking force to the driven wheels if integrating detection is made to the difference between the non-driven wheel speeds and the inferred vehicle running speed of each driven wheel speed.
Because the driven wheels are coupled with each other through a differential gear mechanism, when a moderate increase of the difference takes place, the difference associated with one of the driven wheels increases and the difference associated with the other of the driven wheels decreases.
Since the difference between the actually generated deference and an ideal difference providing a target to be controlled may be positive for one wheel and negative for the other, the behavior of the wheels exhibiting the increased difference can be detected with a sensitivity of a factor of about 2 when the difference of the differences is taken into consideration so that an appropriate braking force can be applied to the wheels exhibiting the increased difference.
Also, when the automotive vehicle is cornering, the mere detection of the difference in speed between the driven wheels and the non-driven wheels would be difficult. Even though the rotational speeds of wheels on the same side are compared, the difference in speed occurring between the driven wheels and the non-driven wheels is not great. Accordingly, particularly where the automotive vehicle is of a front wheel drive type, the positive difference generated between the driven wheels and the non-driven wheels is small. However, when the difference in speed between the non-driven wheels is subtracted from the difference in speed between the driven wheels, any possible influence brought about by the difference between the front and rear wheels during the cornering of the automotive vehicle is negligible. Therefore, the actual excessive increase of the driving force can be detected. This means that the difference of the differences, i.e., the difference between the left-hand driven and non-driven wheels subtracted by the difference between the right-hand driven and non-driven wheels can be used as a target to be controlled by the second control means.
Furthermore, when the difference between the drive and non-driven wheels on the same sides is generated, is negative and is reduced to zero, external disturbance recognition is enhanced.
A combination of the detection of a large difference itself for each wheel, that is, for each driven wheel and the detection of a large differential value of the difference reduces possible influence brought by a cornering of an automotive vehicle to negligible amount by properly providing an excess detection threshold value.
When the present invention is used to suppress the driving force of the prime mover during traction control, the average value of the differences between the left-hand and right-hand driven and non-driven wheels or the difference generated from the wheel side exhibiting a smaller value is used as a target to be controlled. The former value is based on the finding that the output of the prime mover can be expressed in terms of the average value of the rotational speeds of the left-hand and right-hand driven wheels through the differential gear mechanism. The latter value is based on the finding that traction control is generally accomplished by simultaneously suppressing the output of the prime mover and controlling the braking force. The control of the difference between the left-hand and right-hand wheels is performed by the braking force control, which has a quick response.
When differences in the coefficient of friction of the road surface between the left-hand and right-hand wheels are taken into consideration, the greatest difference is in the driven wheels on the slippery road surface. Therefore, the braking force is appropriately applied so that the difference may reach a value corresponding to that generated when the driven wheels are on the less slippery road surface. Therefore, the control of the suppression of the output of the prime mover should be directed to the driven wheels on the less slippery road surface.
If the integrating element of the present invention is applied subject to the average value of the differences between the left-hand wheels and between the right-hand wheels or one of the differences which is smaller than the other of the differences, the prolongation for a long time of excessive output of the prime mover can be avoided thereby leading to improvement in steerability and stability. However, since this does not make it possible to distinguish the condition in which the automotive vehicle is cornering, the difference, which is a target to be controlled, or the threshold value has to be corrected with the difference in speed between the left-hand and right-hand non-driven wheels.
Since the threshold value of the difference related to the integrating element requires a smaller value than the difference (not the differential value) related to normal control, it is preferred to effectuate cornering correction. (In this respect, the difference of the differences used in the braking force control of the previously mentioned traction control is somewhat automatically corrected for the cornering and is, therefore, advantageous).
The application of the present invention during the anti-lock control will be discussed.
The target of anti-lock control is based on the difference between the rotational speeds of the wheels and the inferred vehicle running speed. It is usual to add the degree of acceleration of the wheels to the target of anti-lock control.
In anti-lock control, there are many uncertain elements including the preciseness of the inference of the vehicle running speed, as compared with traction control. Thus, the absolute value of the threshold value must take a great value.
Yet, since the braking force is applied to all four wheels and the wheels exhibit a complicated behavior in view of the frictional retaining force of the road surface on which each of these wheels is held, a numerical value that can be used as reference for the cornering correction can hardly be obtained. (What may be termed left-hand and right-hand non-braked wheels that possibly corresponds to the left-hand and right-hand non-driven wheels in the case of the traction controller does not exist).
Accordingly, in anti-lock control it is difficult for the cornering correction to have a sufficiently practical value with information of wheel rotational speeds and, therefore, it must be omitted (unless the use is made of a lateral accelerometer or a steering angle measuring instrument).
Thus, emphasis is placed on the degree of acceleration decision, and the absolute value of the threshold value applicable to the difference between the wheels of interest and the inferred vehicle running speed is very important.
Because of the foregoing, it is usual that the detection to be performed when the absolute value of the difference increases moderately while the degree of acceleration is small tends to be delayed considerably.
Accordingly, the presence of the integrating element can reduce the absolute value of the threshold value that is applied to the difference that occurs when the absolute value of the degree of acceleration during normal control is small. Therefore, the integrating element of the present invention becomes effective.
Corrections based on the vehicle running speed are preferably applied to either the differences or the threshold values, all which have been discussed in the foregoing. However, examples of these corrections are well known to those skilled in the art and will not, therefore, be discussed in detail.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will become more clearly understood from the detailed description thereof taken in conjunction with preferred embodiments with reference to the accompanying drawings, in which:
FIG. 1 is a circuit block diagram according to one embodiment of the present invention applied to a braking force control portion of the traction control system;
FIG. 2 is a flow chart showing an operation of the embodiment shown in FIG. 1;
FIGS. 3 and 4 are graphs showing waveforms obtained from the system of FIG. 1 according to Example (1);
FIG. 5 is a graph showing waveforms obtained from the system of FIG. 1 according to Example (2);
FIG. 6 is a flow chart showing an operation of Example (2);
FIG. 7 is a circuit block diagram according to another embodiment of the present invention which is applied to a traction control system having both the braking force control and the driving force control; and
FIG. 8 is a circuit block diagram according to a further embodiment of the present invention which is applied to an anti-lock control system.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, there is illustrated a circuit block diagram showing the present invention applied to a braking force control portion of a traction control apparatus, wherein the difference is represented by a spin. It is to be noted that, in the drawings, numeral "1" or "2" affixed to each of the reference characters used therein indicates one of the opposite sides of an automotive vehicle, for example, the right-hand side or the left-hand side.
Reference character VD represents a speed sensor for detecting the speed of the respective driven wheel, reference character VN represents a speed sensor for detecting the speed of the respective non-driven wheel, and reference character S represents a spin amount output unit for outputting a signal indicative of an amount of spin occurring in the driven wheels. The spin amount output unit may be comprised of, for example, a subtractor capable of calculating a difference between the output from the driven wheel speed sensor VD and the output from the non-driven wheel speed sensor VN. It is, however, to be noted that, although the amount of the wheel spin can be indicated by the difference between the speed of rotation of each of the driven wheels and the vehicle speed, it is desirable to effect a correction to the amount of wheel spin particularly during the cornering of the automotive vehicle. To this end, the difference in speed of rotation between the left-hand and right-hand non-driven wheels, or between the right-hand driven wheels and the right-hand non-driven wheels, may be used as a parameter representative of the amount of cornering error. A method of effectuating such a correction during the cornering of the automotive vehicle is disclosed in, for example, Japanese Patent Application No. 60-201233, filed on Sep. 11, 1985, by the same assignee of the present invention.
However, since the cornering correction is necessitated particularly for counteracting with the moderate increase of difference, the cornering correction can be omitted when the second control means of the present invention is used, so far as the braking force control of the traction control is concerned.
It is also to be noted that, it is desirable to render the output from the spin amount output unit S to be zero in the case where the spin amount output unit S takes a negative plus.
Reference character D represents a spin increase rate output unit which may be comprised of, for example, a differentiator capable of differentiating the output from the spin amount output unit S. Reference character SV represents a spin difference output unit for outputting a difference between the amounts of spin occurring on the respective sides of the automotive vehicle.
Reference character BC represents a first control means for controlling a braking force under the normal control. This controller BC is operable to calculate a control variable, expressed by the following equation, with the use of the signals obtained from the spin amount output unit S and the spin increase rate output unit D, and then to effect the normal control, which is disclosed, for example, in a Japanese Patent Application, entitled "Wheel Spin Control Apparatus" and filed Dec. 2, 1986, in the name of the same assignee of the present invention, the filing number of which has not yet been allocated:
FUNC=K.sub.2 ·(SPIN+K.sub.1 ·DSPIN)
wherein K 1 and K 2 represent predetermined constants, respectively, SPIN represents the output from the spin amount output unit S, and DSPIN represents the output from the spin increase rate output unit D.
Reference character BC' represents a second control means for controlling a braking force under the integrating control which is operable to carry out the integrating control, as will be described later, with the use of a signal obtained from a let-hand and right-hand spin difference output unit SV. It is to be noted that the braking force controllers BC1' and BC2' operate when S1>S2 and S1<S2, respectively.
Reference character BA represents a brake actuator operable in response to a command from the braking force controllers BC and BC' to apply or release, or decrease or increase, the braking force, and reference character B represents a brake. Although not shown for the purpose of simplicity, various values, such as coefficients and thresholds used in the braking force controllers BC and BC' can be adjusted based on the vehicle running velocity ##EQU1## and its differential value.
The foregoing embodiment described in connection with FIG. 1 can be constructed with a microcomputer, the sequence of operation of which will now be described with reference to a flow chart shown in FIG. 2.
At step #1, a spin amount calculating block S calculates a difference in rotational speed between the driven and non-driven wheels, representing the amount of spin expressed by the following equation:
SPIN=VD-VN
When this value should take a negative value, it is rendered zero. A spin increase rate calculating block D outputs a differential of the spin amount (VD-VN), that is, the degree of spin acceleration expressed by the following equation: ##EQU2## A left- and right-hand spin difference calculating block SV calculates a difference in spin between the left-hand and right-hand sides that is expressed by the following equation:
S1-S2
At step #2, the braking force controller BC receives the spin (SPIN) and the spin acceleration degree (DSPIN) and then calculates a control variable FUNC expressed by the following equation:
FUNC=K.sub.2 ·(SPIN+K.sub.1 ·DSPIN)
wherein K 1 and K 2 represent predetermined constants, respectively.
Assuming that the amount of spin on the left-hand side and that on the right-hand side have changed as shown by respective curves S 1 and S 2 in FIG. 3(a), the spin differential value, dS 1 /dt, will be as shown in the graph of FIG. 3(b) and, at the same time, the control variable FUNC1 will be as shown in the graph of FIG. 3(d). Also, the left-hand and right-hand spin difference SV will be as shown in the graph of FIG. 3(c). Since the control variable FUNC contains a term representing a differential of the spin, a change in spin can be quickly detected.
In addition, since the control variable FUNC has a term representing a spin amount, the differentiated term ##EQU3## is raised up by the spin amount.
At subsequent steps #3 to #8, based on the control variable FUNC, the behavior of the wheels is detected to carry out the normal control. More specifically, at step #3, a decision is made to determine if the control variable FUNC is equal to or greater than a positive threshold value H 1 . If the control variable FUNC is equal to or greater than the positive threshold value H 1 , step #4 takes place at which it is compared with a stored maximum value FPEAK of the control variable FUNC, which FPEAK has been stored in the previous cycle. If the newly obtained control variable FUNC is equal to or greater than the stored FPEAK, the newly obtained control variable FUNC is written in FPEAK at step #5. Accordingly, when the program flow proceeds from step #3 to step #5 by way of step #4, it means that the control variable FUNC is increasing in a positive direction above the threshold value H 1 . In other words, it means that the excessive spin has occurred and is increasing. Under such a circumstance, at step #13, a quick increase command for quickly increasing the braking force is generated. Accordingly, a signal for the abrupt application of pressure is applied to the brake actuator BA to apply a brake thereby to suppress the excessive spin.
On the other hand, if the result of decision at step #4 has indicated that the newly obtained control variable FUNC is smaller than FPEAK, that is, when the control variable FUNC is above the threshold value H 1 but is decreasing, the program flow proceeds to a calculating block step #12 corresponding to the braking force controller BC', to effect the integrating control.
In the event that the result of decision at step #3 has indicated that the newly obtained control variable FUNC is smaller than the positive threshold value H 1 , the program flow proceeds to step #6 at which a decision is made to determine if the control variable FUNC is equal to or smaller than a negative threshold value H 2 . If the control variable FUNC is equal to or smaller than the negative threshold value H 2 , step #7 takes place at which it is compared with a stored minimum value FPEAK of the control variable FUNC which has been stored in the previous cycle. In the event that the newly obtained control variable FUNC is equal to or smaller than the minimum value FPEAK (that is, if it is greater than the minimum value FPEAK in a negative direction), the newly obtained control variable FUNC is written in FPEAK at step #8. Accordingly, when the program flow proceeds from step #3 to step #8 by ay of steps #6 and #7, it means that the control variable FUNC is decreasing below the threshold value H 2 . In other words, it means that the excessive spin is being suppressed. Under such a circumstance, at step #16, a quick decrease command for quickly decreasing the braking force is generated so that the brake can be weakened. If, however, the result of decision at step #6 has indicated that the control variable FUNC is equal to or greater than the negative threshold value H 2 , that is, when the control variable FUNC takes a value between the threshold values H 1 and H 2 , the program flow proceeds to step #9 to render FPEAK to be ∫0", followed by step #12. Thus, when the control variable FUNC is less than a previously obtained positive peak point, or when it is greater than a previously obtained negative peak point, or when the control variable FUNC takes a value between the threshold values H 1 and H 2 , the program flow proceeds to step #12.
The foregoing illustrates an example of the normal control used to control the braking force during the traction control, and step #12 which will be described in detail hereinbelow constitutes the second control means, that is, the integrating control forming the essence of the present invention.
At step #12, a decision is made to determine if there is a tendency of the difference being moderately increased. If the result of decision at step #12 indicates "YES", a moderate increase command for moderately increasing the braking force is generated at step #14 so that a signal for the moderate application of pressure can be outputted to the brake actuator BA thereby to apply the braking force slowly. But if the result of such decision at step #12 indicates "NO", a moderate decrease command for moderately decreasing the braking force is generated at step #15 so that a signal for moderately decreasing the pressure can be outputted to the brake actuator BA thereby to release the braking force slowly. It is to be noted that both of the signal for the abrupt application of pressure and the signal for the moderate application of pressure can be prepared by varying the level of voltage or current applied to a control valve for changing the hydraulic braking pressure. Alternatively, by intermittently outputting the same voltage level signal to a solenoid actuated valve, the ratio between the outputting time and the non-outputting time can be changed. (This is a so-called pulse width modulation control). Other methods can also be employed. The reducing signal for reducing the pressure can be prepared in a manner similar to that described hereinabove.
Three specific examples of the decision made at step #12 forming the essence of the present invention will now be described.
EXAMPLE (1)
As shown in FIG. 4, when the spin difference SV exceeds the positive threshold value Δ, a timer starts its counting operation, and if the count exceeds To, the moderate increase command is outputted. The outputting of the moderate increase command is ended when the spin difference SV attains a value smaller than the positive threshold value Δ. When the moderate increase command ends, the counter is reset.
Where the spin difference SV takes a negative value, the braking force controller BC1' merely monitors the spin difference SV with no actual operation performed. The braking force controller BC2' operates in a manner similar to the braking force controller BC1'.
However, it may be arranged such that the braking force controllers BC1' and BC2' can be formed as a unitary braking force controller BC'. In such a case, the timer starts counting when the spin difference SV exceeds the negative threshold value Δ in the negative direction. When the timer has counted to To, the moderate increase command is outputted to the brake actuator BA 2 . Thereafter, the outputting of such a moderate increase command is ended when the spin difference SV becomes closer to zero than the negative threshold value Δ. When the moderate increase command ends, the counter is reset. Also, it may be arranged that, instead of immediately resetting the counter, it may be counted backwards when the spin difference SV becomes smaller than the threshold value Δ and ends its count-down operation when it is counted to zero.
EXAMPLE (2)
As shown in FIG. 5, the spin difference SV and the threshold value Δ are compared with each other, and the times T 1 , T 2 and T 3 , during which the spin difference SV has exceeded the threshold value Δ, are added up to obtain a count value ΣTi. While in the meantime, the times T 1 ', T 2 ' and T 3 ', during which the spin difference SV takes a value below the threshold value Δ are separately added to determine a count value ΣTi'. The count values ΣTi and ΣTi' are then compared with each other. If the difference, ΣTi-ΣTi', of these count values is greater than a predetermined difference To, the moderate increase command is generated for a period of time in which the spin difference SV exceeds the threshold value Δ. Then, in the even that the spin difference SV does not exceed the threshold value Δ for a period longer than the predetermined period To', the count values ΣTi and ΣTi' are reset to permit the counting from the beginning.
The above can be expressed by the following equations. First, it is detected that,
To<T.sub.1 +T.sub.2 +. . . -(T.sub.1 '+T.sub.2 '+. . . ) (1)
When the term 2(T 1 '+T 2 '+. . . ) is added to both sides terms of the above equation, the following equation can be obtained:
To+2(T.sub.1 '+T.sub.2' +. . . )<T.sub.1 '+T.sub.2' +. . . +T.sub.1 '+T.sub.2'
Assuming that:
T=T.sub.1 +T.sub.2 +. . . +T.sub.1 '+T.sub.2' +. . . ,
T represents a total length of time from the setting of either one of the times. If this equation is inserted in the above equation, the following equation is obtained, and therefore, equation (1) can be expressed using ΣTi' and T:
To+2(T.sub.1 '+T.sub.2' +. . . )<T
The program steps #12-1 to #12-11 shown in the flow chart of FIG. 6 illustrate the decision made in this Example (2). Referring now to the flow chart of FIG. 6, Ta stands for a time count difference between the time during which the spin difference SV exceeds the threshold value Δ and the time during which it is not in excess of the threshold value Δ, and Tb stands for a time count during which the spin difference SV is lower than the threshold value Δ, and it is used for resetting the timer for counting Ta. It is to be noted that, when the timer count Ta attains a maximum value, for example, 255 counts, it retains the maximum counts until it is reset. This equally applies to the timer count Tb. Hereinafter, the program steps #12-1 to #12-11 for the decision made in this Example (2) will be sequentially described.
At step #12-1, a decision is made to determine if the spin difference SV is greater than the threshold value Δ. If the spin difference SV is greater than the threshold value Δ, the count Tb is rendered to be zero at step #12-2, but if it is smaller than the threshold value Δ, the count Tb is incremented by one at step #12-3. Thereafter, a decision is made at step #12-4 to determine if the count Tb is greater than the predetermined value To'. If the count Tb is found greater than the predetermined value To', the program flow proceeds to step #12-5 to make the count Ta equal to zero and further to step #12-6, but if the count Tb is found smaller than the predetermined value To', the program flow directly proceeds to step #12-6.
At step #12-6, a decision is made again to determine if the spin difference SV is greater than the threshold value Δ. If the spin difference SV is greater than the threshold value Δ, the program flow proceeds to step #12-9 at which the count Ta is incremented by one, and then to step #12-10, but if it is smaller than the threshold value the program flow proceeds to step #12-7. At step #12-7, if it is detected that the count Ta is zero, the program flow proceeds immediately to step #12-10, but if it is detected that the count Ta is not zero, the program flow proceeds to step #12-10 after the count Ta has been decremented by one at step #12-8.
At step #12-10, the count Ta and the predetermined value To are compared with each other, and, if the count Ta is found to be smaller than the predetermined value To, the program flow proceeds to step #15 to generate the moderate decrease command, but if it is greater than the predetermined value To, the program flow proceeds to step #12-11 at which a decision is made to determine if the spin difference SV is greater than the threshold value Δ. If the spin difference SV is found to be greater than the threshold value Δ at step #12-11, the moderate increase command is generated at step #14, but if it is found to be smaller than the threshold value Δ, the moderate decrease command is generated at step #15.
The foregoing is the operation carried out in braking force controller BC1', and the operation carried out in braking force controller BC2' is similar to that described above except the sign for SV being reversed.
EXAMPLE (3)
While in Example (2), the control has been described as carried out on the basis of the aggregated time during which the spin difference SV has exceeded the threshold value Δ and the aggregated time during which the spin difference SV has been reduced below the threshold value Δ, the following Example (3) is carried out with the use of an integrated value of the spin difference SV with respect to the threshold value Δ taken as a center axis. More specifically, ##EQU4## is determined, and the moderate increase command is generated during a period in which the above equation is satisfied and, at the same time, the spin difference SV exceeds the threshold value Δ.
The time at which the integration terminates, that is, the time at which the resetting takes place, is when the period in which the spin difference does not exceed the threshold value has continued for a length of time greater than the predetermined period To', and the time at which the integration starts is when the spin difference has exceeded the threshold value for the first time subsequent to the resetting.
In each of Examples (1), (2) and (3), the threshold value Δ is preferably selected. For example, if DSPIN in the equation of the control variable FUNC is rendered to be zero, that is,
FUNC=K.sub.2 ·SPIN
the threshold value Δ may take a value smaller than the SPIN value which would cause the control variable FUNC to exceed the positive threshold value H 1 . In other words, the threshold value Δ is selected to be smaller than H 1 /K 2 .
Also, the threshold value Δ, as well as the threshold values H 1 and H 2 , is preferably so selected as to be of a value approaching a predetermined value when the vehicle running speed is relatively low, but as to progressively increased so as to approach a predetermined value relative to the vehicle running speed when the vehicle running speed is relatively high.
FIG. 7 illustrates an example in which the second control means of the present invention is applied also to the driving force suppressing control of the traction control. It is to be noted that the upper half of the drawing of FIG. 7 pertains to the braking force control, reference to which has already been made.
Reference character EC represents a normal control portion of the driving force suppressing control. While numerous methods can be contemplated for the normal control, the example is herein illustrated in which a control substantially similar to the normal control portion of the braking force control is carried out in relation to an average difference SA with a differential component added, if necessary. An inference of the level of the braking force is carried out by a block GP with reference to an output value of the braking force control BC. A smaller one of the two inferred braking force levels obtained from the left and right sides of the automotive vehicle is selected at block L, thereby to effectuate the driving force control through the engine.
The essence of the present embodiment lies in the integrating control EC'. Since this is similar to BC' in the braking force control, except that the spin difference in this example is the average spin difference SA, it is obvious that the integrating control system discussed in connection with any one of the Examples (1), (2) and (3) can be equally applicable without being altered.
FIG. 8 illustrates an example in which the present invention is applied to the anti-lock control. According to the anti-lock control, the vehicle running speed Vv is inferred from the behavior of each of the wheels, an a difference between the inferred speed Vv and the rotational speed of each of the wheels is taken as a target to be controlled. It is, however, to be noted that, although only one channel is illustrated in FIG. 8, what is shown therein is in practice required in a number equal to the number of control channels. The number of the channels may be one, two, three or four and, in any event, it is well known in the art.
The anti-lock control is carried out during deceleration of the vehicle, while the previously described traction control is carried out during the acceleration of the vehicle, and therefore, care must be paid to the sign of each of the variables. However, the same idea can be basically applicable to both of them. In other words, based on the difference between the vehicle running speed and the rotations speeds of the wheels and its differential value, the normal control BC is carried out.
BA is employed in the form of a pressure reducing actuator in place of a pressurizing actuator used in the traction control. While the second control means BC' according to the present invention is provided in combination with the normal control BC, the constitution thereof may be identical with that described in connection with any one of Examples (1), (2) and (3), provided that the sign receives thoughtful consideration.
As hereinbefore fully described, since according to the present invention the integrating control (such as in any one of Examples (1), (2) and (3)) is carried out, the moderate generation of the difference which cannot be detectable only with the normal control can be quickly and assuredly detected.
Although the present invention has been described in connection with the preferred embodiments thereof with reference to the accompanying drawings, it is to be noted that various changes and modifications are apparent to those skilled in the art. By way of example, in the foregoing description of the present invention made with reference to the entire drawings, the target of the differentiating operation D has been shown as the difference S. However, since the vehicle running speed providing the criterion for the difference, that is, the differential value of any of the rotational speed of the non-driven wheels and the inferred vehicle running speed is small, the target of the differentiating operation may be directed to the rotational speeds of the driven wheels, not to the difference, and also to the rotational speed of each of the wheels in the case of the anti-lock. In any event, whichever is convenient for the calculation can be employed.
Also, although as a representative example of the normal control a system has been illustrated wherein the difference component and the differential component are compounded into a single function for the comparison with the threshold value, the normal control may not be always limited to such system, but may be a system wherein a combination of results obtained by coordinating the threshold values with the difference and differential components, respectively.
Accordingly, such changes and modifications are to be understood as included within the scope of the present invention as defined by the appended claims, unless they depart therefrom. | A wheel speed control apparatus for controlling a braking force and/or a driving force transmitted to wheels maintains the difference between the peripheral speed of each of the wheels and the vehicle running speed or an inferred value thereof at a value approximating the optimum value. The apparatus includes a normal control that detects and controls the increase or incipient increase of the difference over the absolute value using a differential value of the difference and difference or the rotational speed of the wheels. An integrating control detects and controls the continuation for a certain period of slightly excessive tendency of the absolute value of the difference, by comparing with a predetermined threshold value one of values which is smaller than the value with which, when the differential value is zero, the normal control would determines the excessive different only with the absolute value. | 1 |
BACKGROUND
[0001] This invention relates to a memory device. In addition, the invention relates to a method of forming a corresponding memory device. Semiconductor memory devices include arrays of memory cells that are arranged in rows and columns. The gate electrodes of rows of memory cell transistors are connected by word lines, by which the memory cells are addressed. The word lines usually are formed by patterning a conductive layer stack so as to form single word lines which are arranged in parallel. The word lines are electrically insulated from one another laterally by a dielectric material. The lateral distance between two word lines and the width of a word line sum to the pitch of the array of word lines. The pitch is the dimension of the periodicity of a periodic pattern arrangement. The word lines succeed one another in a completely periodic fashion, in order to reduce the necessary device area as much as possible. Likewise, the bit lines are formed by patterning a conductive layer so as to form the single bit lines which are electrically insulated from one another by a dielectric material.
[0002] An example of a non-volatile memory device is based on the NROM (nitride read-only memory) technology. FIG. 1A illustrates a cross-sectional view of an NROM cell between I and I as is illustrated in FIG. 1B . In one embodiment, the NROM cell is an n-channel MOSFET device, wherein the gate dielectric is replaced with a storage layer stack 46 . As is illustrated in FIG. 1A , the storage layer stack 46 is disposed above the channel 43 and under the gate electrode 44 . The storage layer stack 46 includes a silicon nitride layer 202 , which stores the charge, and two insulating silicon dioxide layers 201 , 203 , which sandwich the silicon nitride layer 202 . The silicon dioxide layers 201 , 203 have a thickness larger than 5 nm to avoid any direct tunnelling. In the NROM cell illustrated in FIG. 1A two charges are stored at each of the edges adjacent to the n source/drain regions 41 , 42 .
[0003] The NROM cell is programmed by channel hot electron injection (CHE), for example, whereas erasing is accomplished by hot hole enhanced tunnelling (HHET), by applying appropriate voltages to the corresponding bit lines and word lines, respectively.
[0004] FIG. 1B illustrates a plan view of an exemplary memory device including an array 100 of a NROM cells. To be more specific, the memory cell array 100 includes word lines 2 extending in a first direction as well as bit lines extending in a second direction. Memory cells 45 are disposed between adjacent bit lines at each point of intersection of a substrate portion with a corresponding word line 2 . The first and second source/drain regions 41 , 42 form part of corresponding bit lines. The gate electrodes 44 form part of a corresponding word line. At a point of intersection of the word lines and bit lines, the bit lines and the word lines are insulated from each other by a thick silicon dioxide layer (not shown). In order to minimize the area required for the memory cell array 100 , it is desirable to reduce the width of the word lines as much as possible. Nevertheless, for contacting the single word lines landing pads 111 having a minimum area are required. Usually, these landing pads 111 are disposed in a fan-out region 110 adjacent to the memory cell array 100 . In order to achieve a contact having an appropriate contact resistance, the area of each of the landing pads 111 must have a minimum value. In the peripheral portion 120 , the transistors for controlling the action of the memory cell array are disposed. In one embodiment, word line drivers, sense amplifiers and other transistors are disposed in the peripheral portion 120 . Usually, the peripheral portion 120 is formed in the CMOS technology. Due to the special programming method for injecting a charge into the memory cells, the transistors disposed in the peripheral portion 120 have to withstand higher voltages than the transistors disposed in the array portion. As a consequence, the channel length of the corresponding transistors in the peripheral portion amount to approximately 0.5 μm and higher. In one embodiment, this channel length cannot be reduced in order to achieve a reduced area of the peripheral portion 120 and, thus, the memory device.
[0005] As is illustrated in FIG. 1B , the word lines 2 have a minimum width wmin and a minimum distance dmin from each other. In order to increase the package density of such a memory cell array, the width and the distance of the word lines could be reduced. However, a reduced width of the word lines will result in an increased sheet resistance resulting in an increased access time and, thus, causing an inferior device performance. In addition, when shrinking the width of the word lines 2 , a minimum contact area in the fan-out region 110 should be maintained. Alternatively, it is possible to further shrink the distance between adjacent word lines. However, if the word line array is patterned by using a photolithography technique that is usually employed, the lateral dimensions of the word lines as well as the distance between neighbouring word lines is limited by the minimal structural feature size which is obtainable by the technology used. A special problem arises if the landing pads and the array of conductive lines are to be patterned by one single lithographic step. In more detail, the area of the landing pads should be large, whereas the distance of the conductive lines should be small. However, a lithographic step for simultaneously image different ground rules is very difficult to implement. Hence, a patterning method is sought by which it is possible to simultaneously pattern structures having a different ground rule.
SUMMARY
[0006] According to one aspect of the present invention, an improved memory device includes a semiconductor substrate having a surface, a plurality of first conductive lines running along a first direction. Each of the first conductive lines have a line width wb and two neighboring ones of the first conductive lines have a distance bs from each other. The line width and the distance is measured perpendicularly with respect to the first direction, respectively, a plurality of second conductive lines running along a second direction, the second direction intersecting the first direction, each of the second conductive lines having a line width wl and two neighboring ones of the second conductive lines having a distance ws from each other, the line width and the distance being measured perpendicularly with respect to the second direction, respectively, a plurality of memory cells, each memory cell being accessible by addressing a corresponding one of said first and second conductive lines, and a plurality of landing pads made of a conductive material, each of the landing pads being connected with a corresponding one of said second conductive lines, wherein each of said landing pads has a width wp and length lp, the width wp being measured perpendicularly with respect to the second direction, the length lp being measured along the second direction, wherein the line width wl of each of the second conductive lines is larger than the distance ws and the width wp of each of the landing pads is larger than the line width wl and the length lp of each of the landing pads is larger than the line width wl.
[0007] Accordingly, one embodiment of the present invention provides a memory device including second conductive lines having a width which is larger than the distance between adjacent lines. As a result, the sheet resistance is reduced with respect to conductive lines that are formed with the same ground rule, the conductive lines having a width which is equal to the distance between adjacent conductive lines. Moreover, since the landing pads have a width and a length which both are larger than the width of the conductive lines, contact pads having an increased area can be accomplished. As a consequence, the contact resistance of the contacts is reduced and a proper alignment of the contacts is ensured.
[0008] In one case, the lines have a pitch of less than 300 nm, in one embodiment, less than 200 nm.
[0009] In the memory device according to one embodiment of the present invention, the first conductive lines can correspond to bit lines and the second conductive lines can correspond to word lines of the memory device, the word lines being disposed above the bit lines, each of the memory cells being able to be accessed by addressing a single bitline or a pair of bitlines and a corresponding word line. Nevertheless, it is also possible that the second conductive lines correspond to the bit lines and the first conductive lines correspond to the word lines.
[0010] In one embodiment, the landing pads are arranged in a staggered fashion with respect to the second direction. Thereby, the device area can further be reduced. In one embodiment, the landing pads can be arranged with an increasing distance with respect to a reference position of the memory device, the distance being measured along the second direction.
[0011] According to one embodiment of the invention, each of the landing pads has a boundary line which is not parallel to any of the first and second directions, the boundary line intersecting the second direction at an angle α. Thereby, a high packaging density of the landing pads can be obtained, while the overlay requirements of the patterning process are less severe. In addition, landing pads having a large area can be obtained. In one embodiment, the following relation holds: tan α=(wl+ws)/(lp+ws).
[0012] In one embodiment, the plurality of landing pads includes a first and a second subset of landing pads, wherein a point of reference of each of the landing pads of one subset can be connected by a straight line, the straight line intersecting the second direction at an angle β. Thereby, also an increased density of the landing pads can be obtained. In one embodiment, the following relation holds: tan β=(wl+ws)/(lp+ws).
[0013] According to one embodiment, the line width wl is larger than the double of the distance ws (wl>2×ws). Thereby, the sheet resistance of the conductive lines can further be reduced.
[0014] According to one embodiment of the present invention, an improved method of forming a memory device includes providing a semiconductor substrate having a surface, providing a plurality of first conductive lines running along a first direction, each of the first conductive lines having a line width wb and two neighboring ones of the first conductive lines having a distance bs from each other, the line width and the distance being measured perpendicularly with respect to the first direction, respectively, providing a plurality of second conductive lines running along a second direction, the second direction intersecting the first direction, each of the second conductive lines having a line width wl and two neighboring ones of the second conductive lines having a distance ws from each other, the line width and the distance being measured perpendicularly with respect to the second direction, respectively, providing a plurality of memory cells, each memory cell being accessible by addressing corresponding ones of said first and second conductive lines, and providing a plurality of landing pads made of a conductive material, each of the landing pads being connected with a corresponding one of said second conductive lines, wherein each of said landing pads has a width wp and length lp, the width wp being measured perpendicularly with respect to the second direction, the length lp being measured along the second direction, wherein the line width wl of each of the second conductive lines is larger than the distance ws and the width wp of each of the landing pads is larger than the line width wl and the length lp of each of the landing pads is larger than the line width wl.
[0015] According to one embodiment, providing the plurality of first or second conductive lines includes the steps of providing a layer stack including at least one conductive layer, providing a hard mask layer and patterning the hard mask layer so as to form hard mask lines, the hard mask lines having a width wl 1 and a distance ws 1 , the hard mask lines having sidewalls, conformally depositing a sacrificial layer, so that the deposited sacrificial layer has horizontal and vertical portions, removing the horizontal portions of the sacrificial layer so as to form spacers on the sidewalls of the hard mask lines, depositing a further layer of the hard mask material, planarizing the surface so that an upper portion of the spacers is uncovered, removing the spacers so as to uncover portions of the layer stack, and etching the uncovered portions of the layer stack thereby forming single conductive lines. Optionally, thereafter, the hard mask material is removed. Nevertheless, the hard mask material can as well be automatically removed by the previous etching steps, or it can be maintained, for example, serving as an insulating layer.
[0016] Thereby, it is possible to form the conductive lines having the defined width and distance from each other in a simple manner. In one embodiment, due to the special steps as listed above, it is possible to form the conductive lines having a distance from each other which is beyond the scope of the current lithography tools. To be more specific, the distance between adjacent conductive lines is smaller than the ground rule F of the technology employed.
[0017] The materials of the hard mask layer and the sacrificial layer can be arbitrarily selected. Nevertheless, the hard mask layer and the sacrificial must be able to be selectively etched with respect to each other and with respect to the material of the top most layer of the layer stack. Examples for the hard mask material include amorphous silicon and a carbon layer as is commonly used. In one embodiment, such a carbon layer is made of elemental carbon, that is, carbon that is not contained in a chemical compound, optionally including additives such as hydrogen. Examples of the sacrificial layer include silicon oxide and others. The step of patterning the hard mask lines may in one embodiment include an isotropic etching step for reducing the line width of the hard mask lines. In addition, the step of patterning the hard mask layer may incluse a photolithographic step for patterning a photoresist layer. In one case, this lithographic step may include an overexposure step. Thereby, the line width of the hard mask lines is further reduced.
[0018] In one embodiment, by the step of patterning the hard mask layer also hard mask pads are formed, the hard mask pads being arranged at an edge region of the array portion defined by the plurality of first and second lines, each of said hard mask pads being connected with a corresponding one of said hard mask lines, by the step of forming spacers also spacers on the sidewalls of the hard mask pads are formed, by the step of depositing a further layer of the hard mask layer, the spaces between adjacent ones of the hard mask pads are filled, by the step of removing the spacers also the spacers on the sidewalls of the hard mask pads are removed, and by the step of etching the uncovered portions of the layer stack also single landing pads are formed, each of the landing pads being connected with a corresponding one of the second conductive lines.
[0019] Accordingly, it is possible to form the conductive lines as well as the landing pads during one patterning step. In one embodiment, since according to the invention, the conductive lines and the landing pads have different dimensions, due to the special combination of the steps of patterning the layer stack as defined above and the patterning of the landing pads, it becomes possible to obtain structures having different dimensions by performing one single lithographic step.
[0020] In one embodiment, the first conductive lines correspond to bit lines and the second conductive lines correspond to word lines of the memory device, the word lines being disposed above the bit lines, each of the memory cells being able to be accessed by addressing a corresponding word line. Nevertheless, as is clearly to be understood, the first conductive lines can as well correspond to the word lines, whereas the second conductive lines correspond to the bit lines.
[0021] According to a further embodiment of the invention, the method further includes depositing a photoresist material covering the hard mask layer, patterning the photoresist material so that finally the portions of the hard mask layer which are located at a position which is not disposed between adjacent hard mask pads are uncovered, etching the hard mask material at those positions which are not covered with the photoresist material so as to uncover portions of the layer stack also at a position which is not disposed between adjacent hard mask pads, so that during the step of etching the uncovered portions of the layer stack also the layer stack is etched at a position which is not disposed between adjacent hard mask pads. Thereby, the additional advantage is achieved that a second set of hard mask pads can be defined in a simple manner. In one embodiment, the second set of hard mask pads will function as a mask for patterning additional landing pads.
[0022] According to a further embodiment, during the step of patterning the photoresist material also the hard mask layer is removed from a selected one of said word lines. As a result it is possible to correspondingly pattern the hard mask layer in one single process step, so as to define the portions at which a word line is to be removed and so as to define a second set of landing pads.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] The accompanying drawings are included to provide a further understanding of the present invention and are incorporated in and constitute a part of this specification. The drawings illustrate the embodiments of the present invention and together with the description serve to explain the principles of the invention. Other embodiments of the present invention and many of the intended advantages of the present invention will be readily appreciated as they become better understood by reference to the following detailed description. The elements of the drawings are not necessarily to scale relative to each other. Like reference numerals designate corresponding similar parts.
[0024] FIG. 1A illustrates a cross-sectional view of a NROM cell.
[0025] FIG. 1B illustrates a plan view on a memory device including NROM cells.
[0026] FIG. 2 illustrates a cross-sectional view of a substrate after patterning a photoresist layer.
[0027] FIG. 3A illustrates the substrate after patterning a hard mask layer.
[0028] FIG. 3B illustrates a plan view on the resulting memory device.
[0029] FIG. 4 illustrates a cross-sectional view of the substrate after depositing a sacrificial layer.
[0030] FIG. 5 illustrates a cross-sectional view of the substrate after etching a spacer.
[0031] FIG. 6 illustrates a cross-sectional view of the substrate after depositing a hard mask material layer.
[0032] FIG. 7 illustrates a cross-sectional view after performing a planarizing step.
[0033] FIG. 8 illustrates a cross-sectional after removing the sacrificial layer.
[0034] FIG. 9A illustrates a cross-sectional view after patterning a photoresist layer.
[0035] FIG. 9B illustrates a plan view on the memory device after patterning the photoresist layer.
[0036] FIG. 10A illustrates a cross-sectional view after partially removing the hard mask layer.
[0037] FIG. 10B illustrates a plan view on the memory device after partially removing the hard mask layer.
[0038] FIG. 11 illustrates a cross-sectional view after patterning the cap nitride layer disposed on of the word line layer stack.
[0039] FIG. 12A illustrates a cross-sectional view of the substrate after patterning the complete word line layer stack.
[0040] FIG. 12B illustrates a plan view on the memory device after completely patterning the word line layer stack.
[0041] FIG. 13 illustrates a plan view of a memory device according to one embodiment of the present invention.
[0042] FIG. 14A illustrates a layout of the fan-out according to a further embodiment of the present invention.
[0043] FIG. 14B illustrates a further possible layout of the fan-out according to one embodiment of the present invention.
DETAILED DESCRIPTION
[0044] The accompanying drawings are included to provide a further understanding of the present invention and are incorporated in and constitute a part of this specification. The drawings illustrate the embodiments of the present invention and together with the description serve to explain the principles of the invention. Other embodiments of the present invention and many of the intended advantages of the present invention will be readily appreciated, as they become better understood by reference to the following detailed description. The elements of the drawings are not necessarily to scale relative to each other. Like reference numerals designate corresponding similar parts.
[0045] In the following cross-sectional views, the left-hand portion illustrates the cross-sectional view of the array portion 100 , whereas the right-hand portion illustrates the cross-sectional view of the peripheral portion 120 . In one embodiment, the left-hand portion is taken between II and II, whereas the right-hand portion is taken between III and III as is also illustrated in FIG. 3B .
[0046] Starting point for performing the method of one embodiment of the present invention is a semiconductor substrate, in one embodiment, a silicon substrate, which in one case is p-doped. In the substrate portion in which the peripheral portion of the memory device is to be formed, a gate oxide layer 50 is grown by thermal oxidation. In the array portion, after depositing a storage layer stack comprising a first SiO 2 layer having a thickness of 1.5 to 10 nm, a Si 3 N 4 layer having a thickness of 2 to 15 nm followed by a second SiO 2 layer having a thickness of 5 to 15 nm, the storage layer stack is patterned so as to form lines. After covering the lines with a protective layer and forming spacers adjacent to the sidewalls of the lines of the layer stack, an implantation step is performed so as to define the source/drain regions in the exposed portions.
[0047] A bit line oxide is provided by performing a deposition step, followed by a step of depositing a word line layer stack. These steps are well known to the person skilled in the art of NROM devices, and a detailed description thereof is omitted.
[0048] As is illustrated in FIG. 2A , as a result, on the surface 10 of the semiconductor substrate 1 in one embodiment, a p-doped semiconductor substrate, in the array portion 100 , the storage layer stack 46 , a word line layer stack 20 , a silicon nitride cap layer 21 and a first hard mask layer 22 are disposed. The word line layer stack 20 usually includes segments of a first polysilicon layer and a second polysilicon layer having a total thickness of approximately 70 to 110 nm, followed by a titanium layer (not shown), a tungsten nitride layer having a thickness of approximately 5 to 20 nm and a tungsten layer having a thickness of approximately 50 to 70 nm. On top of the tungsten layer, a silicon nitride layer 21 having a thickness of approximately 120 to 180 nm is disposed. In the present embodiment, the hard mask layer 22 is made of amorphous silicon. The hardmask layer 22 can have a thickness of approximately 30 to 50 nm.
[0049] In the peripheral portion 120 the same layer stack is disposed on the silicon substrate 1 , with the peripheral gate oxide layer 50 being disposed instead of the storage layer stack 46 . In one embodiment, the thickness of the peripheral gate oxide layer 50 can be different from the thickness of the storage layer stack 46 in the array portion. A photoresist layer is deposited on the resulting surface and patterned so as to form single lines which are disposed in a periodic manner. The resulting structure is illustrated in FIG. 2 , wherein a patterned photoresist layer 23 is illustrated. In one embodiment, the photoresist layer 23 is patterned in a lines/spaces pattern, wherein, in one case, an overexposure is made so as to get the lines smaller than the spaces between adjacent lines. The pitch of the lines/spaces pattern should be at least the twofold of the line width to be achieved.
[0050] As is commonly used, an antireflective coating (ARC) layer may be disposed on top of the hard mask layer, for example, a hard mask layer which is made of carbon. In one embodiment, if carbon is taken as the hard mask material, it is necessary to deposit an SiON layer on top of the carbon layer in order to enable the resist strip. In addition, the ARC layer can be disposed beneath the photoresist layer.
[0051] In the next step, the photoresist pattern is transferred to the hard mask layer 22 . In one embodiment, an etching step is performed, taking the photoresist mask as an etching mask. After removing the photoresist material 23 , the structure illustrated in FIG. 3A is obtained, wherein single lines 221 of the hard mask material 22 are formed. In one embodiment, the width wl 1 of each of the lines should be smaller than the width, ws 1 of the spaces between adjacent lines.
[0052] FIG. 3B illustrates a plan view of the resulting structure. As can be seen, lines 221 of the hard mask material are formed. The lines 221 are connected with hard mask pads 114 which are disposed in the fan-out portion 110 of the memory device. As can be seen from FIG. 4 , lines 221 as well as hard mask pads 114 are formed, whereas the remaining part of the surface is covered with the silicon nitride layer 21 .
[0053] In the next step, a sacrificial layer 24 is deposited on the resulting surface. In one embodiment, the sacrificial layer can be made of silicon dioxide. The sacrificial layer 24 has a thickness which is determined so as to provide a desired line width of the resulting word lines. In one embodiment, the sacrificial layer can have a thickness of 10 to 40 nm, in one embodiment, 20 to 35 nm, depending on the minimal structural feature size F of the technology employed. As can be seen from FIG. 4 , the sacrificial layer 24 is conformally deposited so as to cover the lines 221 in the array portion while forming a planar layer in the peripheral portion 120 .
[0054] The material of the sacrificial layer as well as of the hard mask layer can be arbitrarily selected. However, it is necessary to select a hard mask material which can be etched selectively with respect to the material of the sacrificial layer and the material of the word line cap layer 21 . In addition, it is essential, that the sacrificial layer 24 can be etched selectively with respect to the material of the hard mask layer as well as to the material of the word line cap layer 21 .
[0055] In the next step, a spacer etching step is performed so as to remove the horizontal portions of the sacrificial layer 24 , thereby forming sidewall spacers 241 on the sidewalls of each of the lines 221 . In addition, the sacrificial layer 24 is completely removed from the peripheral portion. Nevertheless, a spacer is also formed adjacent to the hard mask pads 114 which are illustrated in FIG. 3B . A cross-sectional view of the resulting structure is illustrated in FIG. 5 .
[0056] In the next step, a further layer of a hard mask material is deposited. In the present embodiment, accordingly, a further layer of amorphous silicon 25 is deposited, so as to fill the spaces between adjacent lines 221 . As a result, the spaces between adjacent spacers 241 of the sacrificial layer are filled with the hard mask material 22 , 25 . By this step, also the spaces between adjacent hard mask pads 114 are filled. Moreover, the fan-out region 110 as well as the peripheral portion 120 of the memory device are covered with the further layer of the hard mask material. According to one embodiment of the present invention, the further layer of the hard mask material is made of the same material as the hard mask material constituting the lines 221 and hard mask pads 114 . Nevertheless, also a different material could be chosen for the further layer.
[0057] Thereafter, a planarizing step, for example a chemical mechanical polishing (CMP) step or a recess etch is performed, so as to remove the upper portion of the deposited layer 25 . The position, at which the deposited amorphous silicon layer 25 will be removed from the resulting surface is indicated by broken lines in FIG. 6 . As can be seen from FIG. 6 , in the array portion, the amorphous silicon layer 25 is laid over the array of lines 221 made of amorphous silicon, whereas in the peripheral portion 120 a layer of amorphous silicon 25 is formed.
[0058] As is illustrated in FIG. 7 , as a result, lines 221 made of amorphous silicon are formed, which are spaced apart from each other by the silicon dioxide spacer 241 in the array portion 100 . As can further be seen from FIG. 7 , the distance between adjacent lines 221 is reduced to the width of each of the spacers 241 . In the peripheral portion 120 , an unpatterned amorphous silicon layer 25 is formed. In the fan-out portion 110 , hard mask pads 114 are formed, the spaces between the hard mask pads being filled with the hard mask material, with a silicon dioxide spacer 241 being interposed.
[0059] In the next step, an etching step is performed so as to remove the spacer material from adjacent lines 221 of amorphous silicon. The resulting structure is illustrated in FIG. 8 . In one embodiment, in the memory cell array portion 100 , now, single lines 221 of amorphous silicon are formed, whereas in the peripheral portion 120 the amorphous silicon layer 25 is unpatterned.
[0060] In the next step, a further photoresist layer 26 is applied and patterned in accordance with the requirements of the memory device. In one embodiment, in the memory cell array portion 100 , an array opening 261 may be formed, in which selected word lines will be removed in a later process step. In one embodiment, in commonly used NROM layouts, word lines are partially removed. In a later process step, at the location of the removed word lines, bit line contacts for contacting the bit lines can be disposed. In addition, the peripheral gate electrodes and peripheral circuitry can be patterned by the present patterning step. Moreover the fan-out region is patterned so as to form landing pads 111 for contacting the word lines. To be more specific, in the array portion, the photoresist layer forms a blocking mask having boundary line which is not parallel to the first nor to the second direction. Accordingly, the fan-out portion is partially covered by the photoresist material, the boundary between the covered and the uncovered portions being defined by an oblique straight line. Nevertheless, as will be discussed later with reference to FIGS. 14A and 14B , the boundary may as well have a shape which is different from a straight line.
[0061] In addition, in the peripheral portion, the photoresist layer 26 is patterned so as to form peripheral openings 262 and leaving peripheral photoresist portions 263 in accordance with the circuitry to be formed. The resulting structure after patterning the photoresist layer is illustrated in FIG. 9A .
[0062] In the cross-sectional view of FIG. 9A , the left-hand portion is taken between II and II, whereas the right-hand portion is taken between III and III as is also illustrated in FIG. 9B .
[0063] FIG. 9B illustrates a plan view of the resulting memory device. In one embodiment, as can be seen, in the array portion single lines 221 of amorphous silicon are formed, which are spaced apart by portions of the silicon nitride layer 21 . In the fan-out region, the landing pads 111 are partially covered with a photoresist layer 26 . In addition, the spaces between adjacent patterned landing pads 111 are as well partially covered with a photoresist layer 26 . In the peripheral portion, the surface is covered with the layer of the hard mask material, in one embodiment, with the amorphous silicon layer 25 at those portions, which are not covered by the photoresist material, in one embodiment, the patterned photoresist material 263 .
[0064] As can further be seen from FIG. 9B , in the array portion 100 part of the word lines are not covered with the photoresist layer 26 , at those portions corresponding to the array opening 261 . In one embodiment, the exact positioning of the opening 261 is overlay critical whereas the correct position of the peripheral opening 262 at which the surface of the landing pads 111 is covered can be performed less overlay critical. Differently stated, in the array portion the lines 221 of amorphous silicon are protected by the photoresist mask 26 , except at those portions corresponding to the array opening 261 . In addition, the peripheral photoresist portion 263 is patterned in accordance with the peripheral circuitry to be formed. During the next steps, the peripheral portion as well as the fan-out portion are patterned in accordance with the photoresist mask patterned.
[0065] After performing an etching step for removing the amorphous silicon layer, the structure illustrated in FIG. 1O A is obtained. As can be seen, in the word line removal portion 3 the lines 221 of amorphous silicon are removed. Moreover, in the peripheral portion 120 the amorphous silicon layer is etched at those portions which have been uncovered due to the patterning of the photoresist layer.
[0066] FIG. 10B illustrates a plan view on the resulting memory device. In one embodiment, after removing the photoresist layer 26 , now each of the lines 221 of amorphous silicon is connected with a hard mask pad 114 made of amorphous silicon. The fan-out region 110 is insulated from the patterned peripheral portion 121 by the silicon nitride layer 21 . In addition, in the word line removal region, the lines of amorphous silicon are completely removed. Due to the special structure of the photoresist pattern 26 as is illustrated in FIG. 9B , for example, by the step of etching the hard mask layer, a second set 114 b of hard mask pads is formed, in addition to the first set 114 a of hard mask pads.
[0067] In the next step, the silicon nitride layer is etched in the exposed portions taking the patterned hard mask material as an etching mask. As a consequence, lines made of a layer stack comprising the silicon nitride layer as well as the amorphous silicon layer are formed in the array portion as well as in the peripheral portion 120 . The resulting structure is illustrated in FIG. 11 .
[0068] In the next step, a further etching step for etching the word line layer stack 20 is performed so that, as a consequence, single word lines 2 are formed in the array portion 100 , whereas a peripheral gate electrode 51 is formed in the peripheral portion 120 . Thereby, in the present example, the hard mask material is removed. As a consequence, as can be seen from FIG. 12A , the word lines 2 now include the word line layer stack as well as the cap nitride layer 21 . In addition, in the peripheral portion, the peripheral gate electrode 51 is insulated from the substrate material I by the peripheral gate oxide 50 .
[0069] FIG. 12A illustrates a cross-sectional view of the resulting structure.
[0070] In addition, FIG. 12B illustrates a plan view of the resulting structure. As can be seen, now, single word lines 2 are formed which are connected with landing pads 111 . On each of the landing pads 111 , a contact 112 can be formed. The fan-out region 110 is isolated from the peripheral portion 121 by the silicon dioxide material 51 . The contact pads 112 can be connected with a corresponding metal wiring in a following process step.
[0071] As can be seen from the structure illustrated in FIG. 12B , word lines 2 having a minimum distance to each other are accomplished, each of the word lines being connected with a landing pad 111 having a larger area. In one embodiment, the landing pads 111 have a larger width than the word lines. Accordingly, contacts 112 can be disposed on each of the landing pads 111 , a contact resistance of the contact 112 being reduced due to their increased area.
[0072] Starting from the cross-sectional view illustrated in FIG. 12A , the memory device is completed in a manner as is known to the person skilled in the art. In one embodiment, the peripheral portion of the memory device is completed. In addition, in the array portion, insulating layer including BPSG and SiO 2 layers are deposited, followed by the definition of bit line contacts at the positions at which the word lines have been removed. In the MO wiring layer conductive lines supporting the bit lines are provided, so that finally a completed memory device is obtained.
[0073] FIG. 13 illustrates a plan view of a memory device according to one embodiment of the present invention. As can be seen, the word lines have a width wl which is larger than the distance ws between adjacent word lines. Accordingly, the area of the memory cell array can be effectively utilized for providing word lines having a decreased sheet resistance due to their enlarged width. Moreover, since a distance between adjacent word lines is remarkably reduced in the resulting memory cell array, the stray fields of neighbouring word lines will suppress a parasitic transistor which could be formed between adjacent memory cells.
[0074] In more detail, in conventional layouts, such a parasitic transistor has been avoided by performing a so-called anti-punch implant. However, if the distance between neighbouring word lines is reduced, the stray fields will suppress such a parasitic transistor, whereby the process complexity is further reduced while achieving the suppression of the parasitic transistor. In one case, such a stray field has a range of 10 to 20 nm, so that with a reduced distance between the word lines this range is sufficient in order to suppress the parasitic transistor.
[0075] For example, the width wl of the word lines can be at least 60 nm, whereas the distance of word lines can be 20 to 40 nm, for example 36 nm or less. In one embodiment, the following relation may hold: wl>1.5×ws.
[0076] As can further be seen from FIG. 13 , in the fan-out region 110 the landing pads 111 have a width wp and a length lp which both are larger than the width wl of the word lines. As a consequence, the contact resistance of a contact is not increased even though the width of the word lines is decreased.
[0077] Each of the landing pads 111 illustrated in FIG. 13 has a boundary line 62 which is not parallel to any of the first and second directions. In one embodiment, each of the boundary lines 62 intersects the second direction at an angle α. As can be gathered from FIG. 13 , in one embodiment the following relation holds: tan α=(wl+ws)/(lp+ws).
[0078] As has been described above, by the method of the present invention, it is possible, to pattern the word lines and the landing pads 111 which have completely different dimensions in one lithographic step which has been difficult to implement by conventional methods.
[0079] By using a different photolithographic mask for patterning the photoresist layer covering the array portion during the step of defining the landing pads 111 , arbitrary arrangements of landing pads 111 can be implemented. For example, FIGS. 14A and 14B illustrate exemplary patterns of the photoresist material in the step which has been described with reference to FIG. 9B , respectively. As is illustrated, the edge of the photolithographic mask can be different from a straight line so that—as a result—a higher packaging density of the landing pads can be achieved. In one embodiment, in FIGS. 14A and 14B the second set 114 b of hard mask pads 114 are not disposed between the first set 114 a of hard mask pads 114 but they are located outside a region defined by the first set 114 a of hard mask pads 114 .
[0080] As a result, after etching the hard mask material so as to define the landing pads, a first and a second subset of landing pads will be formed. In addition, a point of reference 60 of each of the landing pads of one subset can be connected by a straight line 61 wherein the straight line 61 intersects the second direction at an angle β. In one embodiment, the following relation holds: tan β=(w 1 +ws)/(lp+ws).
[0081] Accordingly, the packaging density of the landing pads can be further increased.
[0082] Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and/or equivalent implementations may be substituted for the specific embodiments shown and described without departing from the scope of the present invention. This application is intended to cover any adaptations or variations of the specific embodiments discussed herein. Therefore, it is intended that this invention be limited only by the claims and the equivalents thereof. | A memory device includes a semiconductor substrate having a surface, a plurality of first and second conductive lines, a plurality of memory cells, and a plurality of landing pads. Each of the first conductive lines has a line width wb and two neighboring ones of the first conductive lines having a distance bs from each other. Each of the second conductive lines has a line width wl and two neighboring ones of the second conductive lines having a distance ws from each other. Each memory cell is accessible by addressing corresponding ones of said first and second conductive lines. Each of the landing pads are made of a conductive material and are connected with a corresponding one of said second conductive lines. Each of said landing pads has a width wp and length lp and the line width wl of each of the second conductive lines is larger than the distance ws and the width wp of each of the landing pads is larger than the line width wl and the length lp of each of the landing pads is larger than the line width wl. | 7 |
FIELD OF THE INVENTION
[0001] This invention relates to the field of characterizing the existence of a disease state; particularly to the utilization of mass spectrometry to elucidate particular biopolymer markers indicative or predictive of a particular disease state, and most particularly to specific biopolymer markers whose up-regulation, down-regulation, or relative presence in disease vs. normal states has been determined to be useful in disease state assessment and therapeutic target recognition, development and validation.
BACKGROUND OF THE INVENTION
[0002] Methods utilizing mass spectrometry for the analysis of a target polypeptide have been taught wherein the polypeptide is first solubilized in an appropriate solution or reagent system. The type of solution or reagent system, e.g., comprising an organic or inorganic solvent, will depend on the properties of the polypeptide and the type of mass spectrometry performed and are well-known in the art (see, e.g., Vorm et al. (1994) Anal. Chem. 66:3281 (for MALDI) and Valaskovic et al. (1995) Anal. Chem. 67:3802 (for ESI). Mass spectrometry of peptides is further disclosed, e.g., in WO 93/24834 by Chait et al.
[0003] In one prior art embodiment, the solvent is chosen so that the risk that the molecules may be decomposed by the energy introduced for the vaporization process is considerably reduced, or even fully excluded. This can be achieved by embedding the sample in a matrix, which can be an organic compound, e.g., sugar, in particular pentose or hexose, but also polysaccharides such as cellulose. These compounds are decomposed thermolytically into CO 2 and H 2 O so that no residues are formed which might lead to chemical reactions. The matrix can also be an inorganic compound, e.g., nitrate of ammonium which is decomposed practically without leaving any residues. Use of these and other solvents are further disclosed in U.S. Pat. No. 5,062,935 by Schlag et al.
[0004] Prior art mass spectrometer formats for use in analyzing the translation products include ionization (I) techniques, including but not limited to matrix assisted laser desorption (MALDI), continuous or pulsed electrospray (ESI) and related methods (e.g., IONSPRAY or THERMOSPRAY), or massive cluster impact (MCI); these ion sources can be matched with detection formats including linear or non-linear reflection time-off-light (TOF), single or multiple quadropole, single or magnetic sector, Fourier Transform ion cyclotron resonance (FTICR), ion trap, and combinations thereof (e.g., ion-trap/time-of-flight). For ionization, numerous matrix/wavelength combinations (MALDI) or solvent combinations (ESI) can be employed. Subattomole levels of protein have been detected, for example, using ESI (Valaskovic, G. A. et al., (1996) Science 273:1199-1202) or MALDI (Li, L. et al., (1996) J. Am. Chem. Soc. 118:1662-1663) mass spectrometry.
[0005] ES mass spectrometry has been introduced by Fenn et al. (J. Phys. Chem. 88, 4451-59 (1984); PCT Application No. WO 90/14148) and current applications are summarized in recent review articles (R. D. Smith et al., Anal. Chem. 62, 882-89 (1990) and B. Ardrey, Electrospray Mass Spectrometry, Spectroscopy Europe, 4, 10-18 (1992)). MALDI-TOF mass spectrometry has been introduced by Hillenkamp et al. (“Matrix Assisted UV-Laser Desorption/Ionization: A New Approach to Mass Spectrometry of Large Biomolecules,” Biological Mass Spectrometry (Burlingame and McCloskey, editors), Elsevier Science Publishers, Amsterdam, pp. 49-60, 1990). With ESI, the determination of molecular weights in femtomole amounts of sample is very accurate due to the presence of multiple ion peaks which all could be used for the mass calculation.
[0006] The mass of the target polypeptide determined by mass spectrometry is then compared to the mass of a reference polypeptide of known identity. In one embodiment, the target polypeptide is a polypeptide containing a number of repeated amino acids directly correlated to the number of trinucleotide repeats transcribed/translated from DNA; from its mass alone the number of repeated trinucleotide repeats in the original DNA which coded it, may be deduced.
[0007] U.S. Pat. No. 6,020,208 utilizes a general category of probe elements (i.e., sample presenting means) with Surfaces Enhanced for Laser Desorption/Ionization (SELDI), within which there are three (3) separate subcategories. The SELDI process is directed toward a sample presenting means (i.e., probe element surface) with surface-associated (or surface-bound) molecules to promote the attachment (tethering or anchoring) and subsequent detachment of tethered analyte molecules in a light-dependent manner, wherein the said surface molecule(s) are selected from the group consisting of photoactive (photolabile) molecules that participate in the binding (docking, tethering, or crosslinking) of the analyte molecules to the sample presenting means (by covalent attachment mechanisms or otherwise).
[0008] PCT/EP/04396 teaches a process for determining the status of an organism by peptide measurement. The reference teaches the measurement of peptides in a sample of the organism which contains both high and low molecular weight peptides and acts as an indicator of the organism's status. The reference concentrates on the measurement of low molecular weight peptides, i.e. below 30,000 Daltons, whose distribution serves as a representative cross-section of defined controls. Contrary to the methodology of the instant invention, the '396 patent strives to determine the status of a healthy organism, i.e. a “normal” and then use this as a reference to differentiate disease states. The present inventors do not attempt to develop a reference “normal”, but rather strive to specify particular markers whose presence, absence or relative strength/concentration in disease vs. normal is diagnostic of at least one specific disease state or whose up-regulation or down-regulation is predictive of at least one specific disease state, whereby the presence of said marker serves as a positive indicator useful in distinguishing disease state. This leads to a simple method of analysis which can easily be performed by an untrained individual, since there is a positive correlation of data. On the contrary, the '396 patent requires a complicated analysis by a highly trained individual to determine disease state versus the perception of non-disease or normal physiology.
[0009] Richter et al, Journal of Chromatography B, 726(1999) 25-35, refer to a database established from human hemofiltrate comprised of a mass database and a sequence database. The goal of Richter et al was to analyze the composition of the peptide fraction in human blood. Using MALDI-TOF, over 20,000 molecular masses were detected representing an estimated 5,000 different peptides. The conclusion of the study was that the hemofiltrate (HF) represented the peptide composition of plasma. No correlation of peptides with relation to normal and/or disease states is made.
[0010] As used herein, “analyte” refers to any atom and/or molecule; including their complexes and fragment ions. The term may refer to a single component or a set of components. In the case of biological molecules/macromolecules or “biopolymers”, such analytes include but are not limited to: polypeptides, polynucleotides, proteins, peptides, antibodies, DNA, RNA, carbohydrates, steroids, and lipids, and any detectable moiety thereof, e.g. immunologically detectable fragments. Note that most important biomolecules under investigation for their involvement in the structure or regulation of life processes are quite large (typically several thousand times larger than H 2 O).
[0011] As used herein, the term “molecular ions” refers to molecules in the charged or ionized state, typically by the addition or loss of one or more protons (H + ).
[0012] As used herein, the term “molecular fragmentation” or “fragment ions” refers to breakdown products of analyte molecules caused, for example, during laser-induced desorption (especially in the absence of added matrix).
[0013] As used herein, the term “solid phase” refers to the condition of being in the solid state, for example, on the probe element surface.
[0014] As used herein, “gas” or “vapor phase” refers to molecules in the gaseous state (i.e., in vacuo for mass spectrometry).
[0015] As used herein, the term “analyte desorption/ionization” refers to the transition of analytes from the solid phase to the gas phase as ions. Note that the successful desorption/ionization of large, intact molecular ions by laser desorption is relatively recent (circa 1988)—the big breakthrough was the chance discovery of an appropriate matrix (nicotinic acid).
[0016] As used herein, the term “gas phase molecular ions” refers to those ions that enter into the gas phase. Note that large molecular mass ions such as proteins (typical mass=60,000 to 70,000 times the mass of a single proton) are typically not volatile (i.e., they do not normally enter into the gas or vapor phase). However, in the procedure of the present invention, large molecular mass ions such as proteins do enter the gas or vapor phase.
[0017] As used herein in the case of MALDI, the term “matrix” refers to any one of several small, acidic, light absorbing chemicals (e.g., CHCA (alpha-cyano-4-hydroxy-cinnamic acid), nicotinic or sinapinic acid) that is mixed in solution with the analyte in such a manner so that, upon drying on the probe element, the crystalline matrix-embedded analyte molecules are successfully desorbed (by laser irradiation) and ionized from the solid phase (crystals) into the gaseous or vapor phase and accelerated as intact molecular ions. For the MALDI process to be successful, analyte is mixed with a freshly prepared solution of the chemical matrix (e.g., 10,000:1 matrix:analyte) and placed on the inert probe element surface to air dry just before the mass spectrometric analysis. The large fold molar excess of matrix, present at concentrations near saturation, facilitates crystal formation and entrapment of analyte.
[0018] As used herein, “energy absorbing molecules (EAM)” refers to any one of several small, light absorbing chemicals that, when presented on the surface of a probe, facilitate the neat desorption of molecules from the solid phase (i.e., surface) into the gaseous or vapor phase for subsequent acceleration as intact molecular ions. The term EAM is preferred, especially in reference to SELDI. Note that analyte desorption by the SELDI process is defined as a surface-dependent process (i.e., neat analyte may be placed on a surface composed of bound EAM or EAM and analyte may be mixed prior to placement on a surface). In contrast, MALDI is presently thought to facilitate analyte desorption by a volcanic eruption-type process that “throws” the entire surface into the gas phase. Furthermore, note that some EAM when used as free chemicals to embed analyte molecules as described for the MALDI process will not work (i.e., they do not promote molecular desorption, thus they are not suitable matrix molecules).
[0019] As used herein, “probe element” or “sample presenting device” refers to an element having the following properties: it is inert (for example, typically stainless steel) and active (probe elements with surfaces enhanced to contain EAM and/or molecular capture devices).
[0020] As used herein, “MALDI” refers to Matrix-Assisted Laser Desorption/Ionization.
[0021] As used herein, “TOF” stands for Time-of-Flight.
[0022] As used herein, “MS” refers to Mass Spectrometry.
[0023] As used herein, “MS/MS” refers to multiple sequential mass spectrometry.
[0024] As used herein “MALDI-TOF MS” refers to Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.
[0025] As used herein, “ESI” is an abbreviation for electrospray ionization.
[0026] As used herein, “chemical bonds” is used simply as an attempt to distinguish a rational, deliberate, and knowledgeable manipulation of known classes of chemical interactions from the poorly defined kind of general adherence observed when one chemical substance (e.g., matrix) is placed on another substance (e.g., an inert probe element surface). Types of defined chemical bonds include electrostatic or ionic (+/−) bonds (e.g., between a positively and negatively charged groups on a protein surface), covalent bonds (very strong or “permanent” bonds resulting from true electron sharing), coordinate covalent bonds (e.g., between electron donor groups in proteins and transition metal ions such as copper or iron), and hydrophobic interactions (such as between two noncharged groups), weak dipole and London force or induced dipole interactions.
[0027] As used herein, “electron donor groups” refers to the case of biochemistry, where atoms in biomolecules (e.g, N, S, O) “donate” or share electrons with electron poor groups (e.g., Cu ions and other transition metal ions).
[0028] As used herein, the term “biopolymer markers indicative or predictive of a disease state” is interpreted to mean that a biopolymer marker which is strongly present in a normal individual, but is down-regulated in disease is predictive of said disease; while alternatively, a biopolymer marker which is strongly present in a disease state, but is down-regulated in normal individuals, is indicative of said disease state. Biopolymer markers which are present in both disease and normal states are indicative/predictive based upon their relative strengths in disease vs. normal, along with the observation regarding when their signal strengthens/weakens relative to disease manifestation or progression.
[0029] As used herein, the term “disease state assessment” is interpreted to mean quantitative or qualitative determination of the presence/absence of the disease, with or without an ability to determine severity, rapidity of onset, or resolution of the disease state, e.g. a return to a normal physiological state.
[0030] As used herein, the term “therapeutic target recognition, development, and validation” refers to any concept or method which enables an artisan to recognize, develop, or validate the efficacy of a therapeutic moiety which is effected in conjunction with a chemical or physical interaction with one or more of the biopolymer markers of the instant invention.
[0031] As used herein, the term “polypeptide” is interpreted to mean a polymer composed of amino acid residues, related naturally occurring structural variants, and synthetic non-naturally occurring analogs thereof linked via peptide bonds, related naturally occurring structural variants, and synthetic non-naturally occurring analogs thereof. Synthetic polypeptides can be synthesized, for example, using an automated polypeptide synthesizer. The term “protein” typically refers to large polypeptides. The term “peptide” typically refers to short polypeptides. “Polypeptide(s)” refers to any peptide or protein comprising two or more amino acids joined to each other by peptide bonds or modified peptide bonds. “Polypeptide(s)” refers to both short chains, commonly referred to as peptides, oligopeptides and oligomers and to longer chains generally referred to as proteins. Polypeptides may contain amino acids other than the 20 gene encoded amino acids. “Polypeptide(s)” include those modified either by natural processes, such as processing and other post-translational modifications, but also by chemical modification techniques. Such modifications are well described in basic texts and in more detailed monographs, as well as in a voluminous research literature, and they are well-known to those of skill in the art. It will be appreciated that the same type of modification may be present in the same or varying degree at several sites in a given polypeptide. Also, a given polypeptide may contain many types of modifications. Modifications can occur anywhere in a polypeptide, including the peptide backbone, the amino acid side-chains, and the amino or carboxyl termini. Modifications include, for example, acetylation, acylation, ADPribosylation, amidation, covalent attachment of flavin, covalent attachment of a heme moiety, covalent attachment of a nucleotide or nucleotide derivative, covalent attachment of a lipid or lipid derivative, covalent attachment of phosphotidylinositol, cross-linking, cyclization, disulfide bond formation, demethylation, formation of covalent cross-link formation of cysteine, formation of pyroglutamate, formylation, gamma-carboxylation, glycosylation, GPI anchor formation, hydroxylation, iodination, methylation, myristoylation, oxidation, proteolytic processing, phosphorylation, prenylation, racemization, glycosylation, lipid attachment, sulfation, gamma-carboxylation of glutamic acid residues, hydroxylation and ADP-ribosylation, selenoylation, sulfation, transfer-RNA mediated addition of amino acids to proteins, such as arginylation, and ubiquitination. See, for instance, PROTEINS—STRUCTURE AND MOLECULAR PROPERTIES, 2nd Ed., T. E. Creighton, W. H. Freeman and Company, New York (1993) and Wold, F., Posttranslational Protein Modifications: Perspectives and Prospects, pgs. 1-12 in POSTTRANSLATIONAL COVALENT MODIFICATION OF PROTEINS, B. C. Johnson, Ed., Academic Press, New York (1983); Seifter et al., Meth. Enzymol. 182:626-646 (1990) and Rattan et al., Protein Synthesis: Posttranslational Modifications and Aging, Ann. N.Y. Acad. Sci. 663: 48-62 (1992). Polypeptides may be branched or cyclic, with or without branching. Cyclic, branched and branched circular polypeptides may result from post-translational natural processes and may be made by entirely synthetic methods, as well.
[0032] As used herein, the term “polynucleotide” is interpreted to mean a polymer composed of nucleotide units. Polynucleotides include naturally occurring nucleic acids, such as deoxyribonucleic acid (“DNA”) and ribonucleic acid (“RNA”) as well as nucleic acid analogs. Nucleic acid analogs include those which include non-naturally occurring bases, nucleotides that engage in linkages with other nucleotides other than the naturally occurring phosphodiester bond or which include bases attached through linkages other than phosphodiester bonds. Thus, nucleotide analogs include, for example and without limitation, phosphorothioates, phosphorodithioates, phosphorotriesters, phosphoramidates, boranophosphates, methylphosphonates, chiral-methyl phosphonates, 2-O-methyl ribonucleotides, peptide-nucleic acids (PNAs), and the like. Such polynucleotides can be synthesized, for example, using an automated DNA synthesizer. The term “nucleic acid” typically refers to large polynucleotides. The term “oligonucleotide” typically refers to short polynucleotides, generally no greater than about 50 nucleotides. It will be understood that when a nucleotide sequence is represented by a DNA sequence (i.e., A, T, G, C), this also includes an RNA sequence (i.e., A, U, G, C) in which “U” replaces T.
[0033] As used herein, the term “detectable moiety” or a “label” refers to a composition detectable by spectroscopic, photochemical, biochemical, immunochemical, or chemical means. For example, useful labels include 32 P, 35 S, fluorescent dyes, electron-dense reagents, enzymes (e.g., as commonly used in an ELISA), biotin-streptavadin, dioxigenin, haptens and proteins for which antisera or monoclonal antibodies are available, or nucleic acid molecules with a sequence complementary to a target. The detectable moiety often generates a measurable signal, such as a radioactive, chromogenic, or fluorescent signal, that can be used to quantitate the amount of bound detectable moiety in a sample. The detectable moiety can be incorporated in or attached to a primer or probe either covalently, or through ionic, van der Waals or hydrogen bonds, e.g., incorporation of radioactive nucleotides, or biotinylated nucleotides that are recognized by streptavadin. The detectable moiety may be directly or indirectly detectable. Indirect detection can involve the binding of a second directly or indirectly detectable moiety to the detectable moiety. For example, the detectable moiety can be the ligand of a binding partner, such as biotin, which is a binding partner for streptavadin, or a nucleotide sequence, which is the binding partner for a complementary sequence, to which it can specifically hybridize. The binding partner may itself be directly detectable, for example, an antibody may be itself labeled with a fluorescent molecule. The binding partner also may be indirectly detectable, for example, a nucleic acid having a complementary nucleotide sequence can be a part of a branched DNA molecule that is in turn detectable through hybridization with other labeled nucleic acid molecules. (See, e.g., P. D. Fahrlander and A. Klausner, Bio/Technology (1988) 6:1165.) Quantitation of the signal is achieved by, e.g., scintillation counting, densitometry, or flow cytometry.
[0034] As used herein, the term “antibody or antibodies” includes polyclonal and monoclonal antibodies of any isotype (IgA, IgG, IgE, IgD, IgM), or an antigen-binding portion thereof, including but not limited to F(ab) and Fv fragments, single chain antibodies, chimeric antibodies, humanized antibodies, and a Fab expression library. “Antibody” refers to a polypeptide ligand substantially encoded by an immunoglobulin gene or immunoglobulin genes, or fragments thereof, which specifically binds and recognizes an epitope (e.g., an antigen). The recognized immunoglobulin—genes include the kappa and lambda light chain constant region genes, the alpha, gamma, delta, epsilon and mu heavy chain constant region genes, and the myriad immunoglobulin variable region genes. Antibodies exist, e.g., as intact immunoglobulins or as a number of well characterized fragments produced by digestion with various peptidases. This includes, e.g., Fab′ and F(ab)′ 2 fragments. The term “antibody,” as used herein, also includes antibody fragments either produced by the modification of whole antibodies or those synthesized de novo using recombinant DNA methodologies. It also includes polyclonal antibodies, monoclonal antibodies, chimeric antibodies and humanized antibodies. “Fc” portion of an antibody refers to that portion of an immunoglobulin heavy chain that comprises one or more heavy chain constant region domains, CH, CH 2 and CH 3 , but does not include the heavy chain variable region.
[0035] As used herein, the term “moieties” refers to an indefinite portion of a sample.
[0036] A “ligand” is a compound that specifically binds to a target molecule.
[0037] A “receptor” is a compound or portion of a structure that specifically binds to a ligand.
[0038] A ligand or a receptor (e.g., an antibody) “specifically binds to” or “is specifically immunoreactive with” a compound analyte when the ligand or receptor functions in a binding reaction which is determinative of the presence of the analyte in a sample of heterogeneous compounds. Thus, under designated assay (e.g., immunoassay) conditions, the ligand or receptor binds preferentially to a particular analyte and does not bind in a significant amount to other compounds present in the sample. For example, a polynucleotide specifically binds under hybridization conditions to an analyte polynucleotide comprising a complementary sequence; an antibody specifically binds under immunoassay conditions to an antigen analyte bearing an epitope against which the antibody was raised; and an adsorbent specifically binds to an analyte under proper elution conditions.
[0039] As used herein, the term “pharmaceutically effective carrier” refers to any solid or liquid material which may be used in creating formulations that further include active ingredients of the instant invention, e.g. biopolymer markers or therapeutics, for administration to a patient.
[0040] As used herein, the term “agent” is interpreted to mean a chemical compound, a mixture of chemical compounds, a sample of undetermined composition, a combinatorial small molecule array, a biological macromolecule, a bacteriophage peptide display library, a bacteriophage antibody (e.g., scFv) display library, a polysome peptide display library, or an extract made from biological materials such as bacteria, plants, fungi, or animal cells or tissues. Suitable techniques involve selection of libraries of recombinant antibodies in phage or similar vectors. See, Huse et al. (1989) Science 246: 1275-1281; and Ward et al. (1989) Nature 341: 544-546. The protocol described by Huse is rendered more efficient in combination with phage display technology. See, e.g., Dower et al., WO 91/17271 and McCafferty et al., WO 92/01047.
[0041] As used herein, the term “isolated” is interpreted to mean altered “by the hand of man” from its natural state, i.e., if it occurs in nature, it has been changed or removed from its original environment, or both. For example, a polynucleotide or a polypeptide naturally present in a living organism is not “isolated,” but the same polynucleotide or polypeptide separated from the coexisting materials of its natural state is “isolated”, as the term is employed herein.
[0042] As used herein, the term “variant” is interpreted to mean a polynucleotide or polypeptide that differs from a reference polynucleotide or polypeptide respectively, but retains essential properties. A typical variant of a polynucleotide differs in nucleotide sequence from another, reference polynucleotide. Changes in the nucleotide sequence of the variant may or may not alter the amino acid sequence of a polypeptide encoded by the reference polynucleotide. Nucleotide changes may result in amino acid substitutions, additions, deletions, fusions and truncations in the polypeptide encoded by the reference sequence, as discussed below. A typical variant of a polypeptide differs in amino acid sequence from another, reference polypeptide. Generally, differences are limited so that the sequences of the reference polypeptide and the variant are closely similar overall and, in many regions, identical. A variant and reference polypeptide may differ in amino acid sequence by one or more substitutions, additions, deletions in any combination. A substituted or inserted amino acid residue may or may not be one encoded by the genetic code. A variant of a polynucleotide or polypeptide may be a naturally occurring such as an allelic variant, or it may be a variant that is not known to occur naturally. Non-naturally occurring variants of polynucleotides and polypeptides may be made by mutagenesis techniques, by direct synthesis, and by other recombinant methods known to skilled artisans.
[0043] As used herein, the term “biopolymer marker” refers to a polymer of biological origin, e.g. polypeptides, polynucleotides, polysaccharides or polyglycerides (e.g., dior tri-glycerides), and may include any fragment, e.g. immunologically reactive fragments, variants or moieties thereof.
[0044] As used herein, the term “fragment” refers to the products of the chemical, enzymatic, or physical breakdown of an analyte. Fragments may be in a neutral or ionic state.
[0045] As used herein, the term “therapeutic avenues” is interpreted to mean any agents, modalities, synthesized compounds, etc., which interact with a biopolymer marker in any manner that facilitates a therapeutic benefit, including immunotherapeutic intervention, e.g. modalities such as administration of an immunologically reactive moiety capable of altering the course, progression and/or manifestation of the disease, as a result of interfering with the disease manifestation process, for example, at the early stages focused upon by the identification of the disease, such as by supplying a moiety capable of modifying the pathogenicity of lymphocytes specific for the biopolymer marker or related components.
[0046] As used herein, the term “interacting with a biopolymer marker” includes any process by which a biopolymer marker may physically or chemically relate with an organism, particularly when this interaction results in the development of therapeutic avenues or in modulation of the disease state.
[0047] As used herein, the term “therapeutic targets” may thus be defined as those analytes which are capable of exerting a modulating force, wherein “modulation” is defined as an alteration in function inclusive of activity, synthesis, production, and circulating levels. Thus, modulation effects the level or physiological activity of at least one particular disease related biopolymer marker or any compound or biomolecule whose presence, level or activity is linked either directly or indirectly, to an alteration of the presence, level, activity or generic function of the biopolymer marker, and may include pharmaceutical agents, biomolecules that bind to the biopolymer markers, or biomolecules or complexes to which the biopolymer markers bind. The binding of the biopolymer markers and the therapeutic moiety may result in activation (agonist), inhibition (antagonist), or an increase or decrease in activity or production (modulator) of the biopolymer markers or the bound moiety. Examples of such therapeutic moieties include, but are not limited to, antibodies, oligonucleotides, proteins (e.g., receptors), RNA, DNA, enzymes, peptides or small molecules. With regard to immunotherapeutic moieties, such a moiety may be defined as an effective analog for a major epitope peptide which has the ability to reduce the pathogenicity of key lymphocytes which are specific for the native epitope. An analog is defined as having structural similarity but not identity in peptide sequencing able to be recognized by T-cells spontaneously arising and targeting the endogeneous self epitope. A critical function of this analog is an altered T-cell activation which leads to T-cell anergy or death.
[0048] With the advent of mass spectrometric methods such as MALDI and SELDI and ESI, researchers have begun to utilize a tool that holds the promise of uncovering countless biopolymers which result from translation, transcription and post-translational transcription of proteins from the entire genome.
[0049] Operating upon the principles of retentate chromatography, SELDI MS involves the adsorption of proteins, based upon their physico-chemical properties at a given pH and salt concentration, followed by selectively desorbing proteins from the surface by varying pH, salt, or organic solvent concentration. After selective desorption, the proteins retained on the SELDI surface, the “chip”, can be analyzed using the CIPHERGEN protein detection system, or an equivalent thereof. Retentate chromatography is limited, however, by the fact that if unfractionated body fluids, e.g. blood, blood products, urine, saliva, cerebrospinal fluid, luymph and the like, along with tissue samples, are applied to the adsorbent surfaces, the biopolymers present in the greatest abundance will compete for all the available binding sites and thereby prevent or preclude less abundant biopolymers from interacting with them, thereby reducing or eliminating the diversity of biopolymers which are readily ascertainable.
[0050] If a process could be devised for maximizing the diversity of biopolymers discernable from a sample, the ability of researchers to accurately determine the relevance of such biopolymers with relation to one or more disease states would be immeasurably enhanced.
SUMMARY OF THE INVENTION
[0051] The instant invention is characterized by the use of a combination of preparatory steps, e.g. chromatography and 1-D tricine polyacrylamide gel electrophoresis. Subsequent to which the gel is stained, e.g. with Coomasie blue, silver or rubidium. Next, bands are selected from the gels for further study. Tryptic digestion of each band follows, concluding with the extraction of tryptic peptides from the digest. This extraction may be accomplished utilizing C18 ZIPTIPs, or organic extract and dry technique followed by MALDI Qq TOF (Maldi Quadrupole Quadrupole Time of Flight) processing.
[0052] Additional methodologies may include SELDI MS, 2-D gel technology, MALDI MS/MS and time-of-flight detection procedures to maximize the diversity of biopolymers which are verifiable within a particular sample. The cohort of biopolymers verified within a sample is then compared to develop data indicating their presence, absence or relative strength/concentration in disease vs normal controls, and further studied to determine whether the up-regulation or down-regulation of a single biopolymer or group of biopolymers is indicative of a disease state or predictive of the development of said disease state. Additionally, biopolymers recognized as being indicative or predictive of a disease state in accordance with the instant invention are useful in therapeutic intervention, e.g. as therapeutic modalities in their own right, in the course of therapeutic target recognition, in the development and validation of efficacious therapeutic modalities, e.g when interrogating or developing phage display libraries, and as ligands or receptors for use in conjunction with therapeutic intervention.
[0053] Although all manner of biomarkers related to all disease conditions are deemed to be within the purview of the instant invention and methodology, particular significance was given to those markers and diseases associated with the complement system, cognitive diseases, e.g. Alzheimer's disease and Syndrome X and diseases related thereto.
[0054] The complement system is an important part of non-clonal or innate immunity that collaborates with acquired immunity to destroy invading pathogens and to facilitate the clearance of immune complexes from the system. This system is the major effector of the humoral branch of the immune system, consisting of nearly 30 serum and membrane proteins. The proteins and glycoproteins composing the complement system are synthesized largely by liver hepatocytes. Activation of the complement system involves a sequential enzyme cascade in which the proenzyme product of one step becomes the enzyme catalyst of the next step. Complement activation can occur via two pathways: the classical and the alternative. The classical pathway is commonly initiated by the formation of soluble antigen-antibody complexes or by the binding of antibody to antigen on a suitable target, such as a bacterial cell. The alternative pathway is generally initiated by various cell-surface constituents that are foreign to the host. Each complement component is designated by numerals (C1-C9), by letter symbols, or by trivial names. After a component is activated, the peptide fragments are denoted by small letters. The complement fragments interact with one another to form functional complexes. Ultimately, foreign cells are destroyed through the process of a membrane-attack complex mediated lysis.
[0055] The C4 component of the complement system is involved in the classical activation pathway. It is a glycoprotein containing three polypeptide chains (α, β, and γ). C4 is a substrate of component C1s and is activated when C1s hydrolyzes a small fragment (C4a) from the amino terminus of the α chain, exposing a binding site on the larger fragment (C4b).
[0056] The native C3 component consists of two polypeptide chains, α and β. As a serum protein, C3 is involved in the alternative pathway. Serum C3, which contains an unstable thioester bond, is subject to slow spontaneous hydrolysis into C3a and C3b. The C3f component is involved in the regulation required of the complement system which confines the reaction to designated targets. During the regulation process, C3b is cleaved into two parts: C3bi and C3f. C3bi is a membrane-bound intermediate wherein C3f is a free diffusible (soluble) component.
[0057] Complement components have been implicated in the pathogenesis of several disease conditions. C3 deficiencies have the most severe clinical manifestations, such as recurrent bacterial infections and immune-complex diseases, reflecting the central role of C3. The rapid profusion of C3f moieties and resultant “accidental” lysis of normal cells mediated thereby gives rise to a host of auto-immune reactions. The ability to understand and control these mechanisms, along with their attendant consequences, will enable practitioners to develop both diagnostic and therapeutic avenues by which to thwart these maladies.
[0058] In the course of defining a plurality of disease specific marker sequences, special significance was given to markers which were evidentiary of a particular disease state or with conditions associated with Syndrome-X. Syndrome-X is a multifaceted syndrome, which occurs frequently in the general population. A large segment of the adult population of industrialized countries develops this metabolic syndrome, produced by genetic, hormonal and lifestyle factors such as obesity, physical inactivity and certain nutrient excesses. This disease is characterized by the clustering of insulin resistance and hyperinsulinemia, and is often associated with dyslipidemia (atherogenic plasma lipid profile), essential hypertension, abdominal (visceral) obesity, glucose intolerance or noninsulin-dependent diabetes mellitus and an increased risk of cardiovascular events. Abnormalities of blood coagulation (higher plasminogen activator inhibitor type I and fibrinogen levels), hyperuricemia and microalbuminuria have also been found in metabolic syndrome-X.
[0059] The instant inventors view the Syndrome X continuum in its cardiovascular light, while acknowledging its important metabolic component. The first stage of Syndrome X consists of insulin resistance, abnormal blood lipids (cholesterol, triglycerides and free fatty acids), obesity, and high blood pressure (hypertension). Any one of these four first stage conditions signals the start of Syndrome X.
[0060] Each first stage Syndrome X condition risks leading to another. For example, increased insulin production is associated with high blood fat levels, high blood pressure, and obesity. Furthermore, the effects of the first stage conditions are additive; an increase in the number of conditions causes an increase in the risk of developing more serious diseases on the Syndrome X continuum.
[0061] A patient who begins the Syndrome X continuum risks spiraling into a maze of increasingly deadly diseases. The next stages of the Syndrome X continuum lead to overt diabetes, kidney failure, and heart failure, with the possibility of stroke and heart attack at any time. Syndrome X is a dangerous continuum, and preventative medicine is the best defense. Diseases are currently most easily diagnosed in their later stages, but controlling them at a late stage is extremely difficult. Disease prevention is much more effective at an earlier stage.
[0062] In a further contemplated embodiment of the invention, samples may be taken from a patient at one point in time, as a single sample or as multiple samples, or at different points in time such that analysis is carried out on multiple samples for ongoing analysis. Typically, a first sample is taken from a patient upon presentation with possible symptoms of a disease and analyzed according to the invention. Subsequently, some period of time after presentation, for example, about 3-6 months after the first presentation, a second sample is taken and analyzed according to the invention. The data can be used, by way of example, to diagnose or monitor a disease state, determine risk assessment, identify therapeutic avenues, or determine the therapeutic value of an agent such as a pharmaceutical.
[0063] Subsequent to the isolation of particular disease state marker sequences as taught by the instant invention, the promulgation of various forms of risk assessment tests are contemplated which will allow physicians to identify asymptomatic patients before they suffer an irreversible event such as diabetes, kidney failure, and heart failure, and enable effective disease management and preventative medicine. Additionally, the specific diagnostic tests which evolve from this methodology provide a tool for rapidly and accurately diagnosing acute Syndrome X events such as heart attack and stroke, and facilitate treatment.
[0064] More particularly, biopolymer markers elucidated via methodologies of the instant invention find utility related to broad areas of disease therapeutics. Such therapeutic avenues include, but are not limited to:
[0065] 1) utilization and recognition of said biopolymer markers, variants or moieties thereof as direct therapeutic modalities, either alone or in conjunction with an effective amount of a pharmaceutically effective carrier;
[0066] 2) validation of therapeutic modalities or disease preventative agents as a function of biopolymer marker presence or concentration;
[0067] 3) treatment or prevention of a disease state by formation of disease intervention modalities; e.g. formation of biopolymer/ligand conjugates which intervene at receptor sites to prevent, delay or reverse a disease process;
[0068] 4) use of biopolymer markers or moieties thereof as a means of elucidating therapeutically viable agents, e.g. from a bacteriophage peptide display library, a bacteriophage antibody library or the like;
[0069] 5) instigation of a therapeutic immunological response; and
[0070] 6) synthesis of molecular structures related to said biopolymer markers, moieties or variants thereof which are constructed and arranged to therapeutically intervene in the disease process.
[0071] A process for identifying or developing therapeutic avenues related to a disease state utilizing any of the above examples may follow results obtained from conducting an analysis inclusive of interacting with a biopolymer including the sequence of the particular disease specific marker or at least one analyte thereof of the present invention. Such treatment or prevention of a disease state by formation of disease intervention modalities may be by the formation of biopolymer/ligand conjugates which intervene at receptor sites to prevent, delay, or reverse a disease process. In addition, a means of elucidating therapeutically viable agents may include the use of a bacteriophage peptide display library or a bacteriophage antibody library. The therapeutic avenues may regulate the presence or absence of the biopolymer including the sequence of the particular disease specific marker or at least one analyte thereof in the present invention.
[0072] Accordingly, it is an objective of the instant invention to define a disease specific biopolymer marker sequence which is useful in evidencing and categorizing at least one particular disease state.
[0073] It is an additional objective of the instant invention to develop methods and means of disease therapy, including but not limited to:
[0074] 1) utilization and recognition of said biopolymer markers, variants or moieties thereof as direct therapeutic modalities, either alone or in conjunction with an effective amount of a pharmaceutically effective carrier;
[0075] 2) validation of therapeutic modalities or disease preventative agents as a function of biopolymer marker presence or concentration;
[0076] 3) treatment or prevention of a disease state by formation of disease intervention modalities; e.g. formation of biopolymer/ligand conjugates which intervene at receptor sites to prevent, delay or reverse a disease process;
[0077] 4) use of biopolymer markers or moieties thereof as a means of elucidating therapeutically viable agents, e.g. from a bacteriophage peptide display library, a bacteriophage antibody library or the like;
[0078] 5) instigation of a therapeutic immunological response; and
[0079] 6) synthesis of molecular structures related to said biopolymer markers, moieties or variants thereof which are constructed and arranged to therapeutically intervene in the disease process, e.g. by directly determining the three-dimensional structure of said biopolymer marker directly from an amino acid sequence thereof.
[0080] It is another objective of the instant invention to evaluate samples containing a plurality of biopolymers for the presence of disease specific biopolymer marker sequences (disease specific markers) which evidence a link to at least one specific disease state.
[0081] It is a further objective of the instant invention to elucidate essentially all biopolymeric markers, moieties or variants thereof contained within said samples, whereby particularly significant moieties may be identified.
[0082] It is a further objective of the instant invention provide at least one purified antibody which is specific to said disease specific marker sequence.
[0083] It is yet another objective of the instant invention to teach a monoclonal antibody which is specific to said disease specific marker sequence.
[0084] It is a still further objective of the invention to teach polyclonal antibodies raised against said disease specific marker.
[0085] It is yet an additional objective of the instant invention to teach a diagnostic kit for determining the presence, concentration, or relative strength/concentration of said disease specific marker.
[0086] It is a still further objective of the instant invention to teach methods for characterizing disease state based upon the identification of said disease specific marker.
[0087] Other objects and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this invention. The drawings constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof.
BRIEF DESCRIPTION OF THE FIGURES
[0088] [0088]FIG. 1 is a photograph of a tricine gel DEAE 2 (Elution) comparing Insulin Resistance versus Normal;
[0089] [0089]FIG. 2 is a trypsin digested spectra graph depicting the ion 1301;
[0090] [0090]FIG. 3 is a trypsin digested spectra graph depicting the ion 1187.
DETAILED DESCRIPTION OF THE INVENTION
[0091] In earlier work, for example in U.S. patent application Ser. No. 09/846330 filed Apr. 30, 2000, the contents of which is herein incorporated by reference, raw sera was obtained and mixed with formic acid and extracted the peptides with C18 reversed phase ZIPTIPs.
[0092] In the instantly disclosed invention, we deal with proteins generally having a molecular weight of about 20 kD or more. In general, proteins of greater than 20 kD can reliably be fragmented by trypsin or other enzymes. The instant technology incorporates sufficient sensitivity to deal with even the low production of peptides from proteins less than 20 kD clipped from gel.
[0093] Proteins differ from peptides in that they cannot be effectively resolved by time of flight MS and they are too large (>3 kD) to be effectively fragmented by collision with gases. The most commonly used solution to these problems is to resolve the proteins by polyacrylamide gel electrophoresis followed by staining with silver, or coomasie brilliant blue or rubidium dyes or counter staining with Zinc-SDS complexes. Once the proteins have been resolved and visualized with stains the proteins that differ between disease states can then be excised from the gel and the protein purified in the 1-D gel band or 2-D gel spot can be cleaved into fragments less that 3 kD by proteolytic enzymes. Once protein has been resolved by gel and cleaved by enzymes, the protein is considered in the form of peptides and therefore can be dealt with as per earlier work (09/846330). The peptide is either collected and purified with C18 reversed phase chromatography or by some other form of chromatography prior to reversed phase separation. The peptide can also be collected in ammonium carbonate buffer that is subsequently evolved by reaction with acid or by removal in organic solvents.
[0094] Once the peptides are collected they can be sequenced, e.g. with a MALDI-Qq-TOF but also with a TOF-TOF, and ESI-Q-TOF or an ION-TRAP. Other types of MS analysis which may be employed are SELDI MS and MS/MS. The peptides are fragments of the original protein. The peptides are sequenced by fragmentation to produced a spectrum composed of the parts of the peptide. The peptide fragments can be produced by a strong ionization energy with a laser, temperature, electron capture, collision between the peptides themselves or with other objects such as gas molecules. The spacing in terms of mass between the parts of the peptides is a fragmentation pattern. The fragmentation pattern of each peptide from the starting mass to the last remaining amino acid (from either end) is unique.
[0095] The human genome contains the genes that encode all proteins. The proteolytic cut sites within all these proteins can be predicted from the translated amino acid sequence. The mass of the peptides that result from the predicting cut sites can be calculated. Similarly, the fragmentation pattern from each hypothetical peptide can be predicted. Thus, we can conceptually digest the proteins within the human proteome and fragment them.
[0096] When a peptide has been “sequenced” it is understood that the peptide fragment has been purified by one of the methods above, i.e. Time of flight (TOF) or by chromatography, before fragmenting it with gas to produce the peptide fragments. The original peptide mass and fragmentation pattern obtained is then fit to those from the theoretical digestion and fragmentation of the genome. The peptide that best matches the theoretical peptides and fragments and is biologically possible, i.e. a potential human blood-borne protein, is thus identified. It is possible to identify plural targets in this fashion.
[0097] Following are exemplary, but non-limiting examples of preparatory protocols useful in the process of the instant invention.
[0098] Preparatory Protocols:
[0099] Any of these protocols may be selected from a column flow-through stream, a column elution stream, or a column scrub stream.
[0100] Hi Q is a strong anion exchanger made of methyl acrylate co-polymer with the functional group: —N + (CH 3 ) 2 ;
[0101] Hi S is a strong cation exchanger made of methyl acrylate co-polymer with the functional group: —SO 3 − ;
[0102] DEAE is diethylaminoethyl which is a weak cation exchanger made of methyl acrylate co-polymer with the functional group —N + (C 2 H 5 ) 2 ;
[0103] PS is phenyl sepharose;
[0104] BS is butyl sepharose.
[0105] Note that the supports, i.e. methyl acrylate and sepharose are different, but non-limiting examples, as the same functional group on different supports will function, albeit possibly with different effects.
[0106] DEAE Column Protocol:
[0107] 1)Cast 200 μl of 50% slurry;
[0108] 2)Equilibrate column in 5 bed volumes of 50 mM tricine pH 8.8 (binding buffer);
[0109] 3)Dissolve 25 μl of sera in 475 μl of binding buffer;
[0110] 4)Wash column in 5 bed volumes of binding buffer;
[0111] 5)Elute column in 120 μl of 0.4 M Phosphate buffer (PB) pH 6.1;
[0112] 6)Elute column in 120 μl of 50 mM citrate buffer pH 4.2;
[0113] 7)Scrub column with 120 μl sequentially with each of 0.1% triton, 1.0% triton and 2% SDS in 62.5 mM Tris pH 6.8.
[0114] Butyl Sepharose Column Protocol:
[0115] 1)Cast 150 μl bed volume column;
[0116] 2)Equilibrate column in 5 bed volumes of 1.7 M (NH 4 ) 2 SO 4 in 50 mM PB pH 7.0 (binding buffer);
[0117] 3)Dissolve 35 μl of sera in 465 μl of binding buffer and apply;
[0118] 4)Wash column in 5 bed volumes of binding buffer;
[0119] 5)Elute column in 120 μl of 0.4 M (NH 4 ) 2 SO 4 in 50 mM PB pH 7.0;
[0120] 6)Elute column in 120 μl of 50 mM PB pH 7.0;
[0121] 7)Scrub column with 120 μl sequentially with each of 0.1% triton, 1.0% triton and 2% SDS in 62.5 mM Tris pH 6.8.
[0122] Phenyl Sepharose Column Protocol:
[0123] 1)Cast 150 μl bed volume column;
[0124] 2)Equilibrate column in 5 bed volumes of 1.7 M (NH 4 ) 2 SO 4 in 50 mM PB pH 7.0 (binding buffer);
[0125] 3)Dissolve 35 μl of sera in 465 μl of binding buffer and apply;
[0126] 4)Wash column in 5 bed volumes of binding buffer;
[0127] 5)Elute column in 120 μl of 0.2 M (NH 4 ) 2 SO 4 in 50 mM PB pH 7.0;
[0128] 6)Elute column in 120 μl of 50 mM PB pH 7.0;
[0129] 7)Scrub column with 120 μl sequentially with each of 0.1% triton, 1.0% triton and 2% SDS in 62.5 mM Tris pH 6.8.
[0130] HiO Anion Exchange Mini Column Protocol:
[0131] 1)Dilute sera in sample/running buffer;
[0132] 2)Add HiQ resin to column and remove any air bubbles;
[0133] 3)Add ultrafiltered (UF) water to aid in column packing;
[0134] 4)Add sample/running buffer to equilibrate column;
[0135] 5)Add diluted sera;
[0136] 6)Collect all the flow-through fraction in Eppendorf tubes until level is at resin;
[0137] 7)Add sample/running buffer to wash column;
[0138] 8)Add elution buffer and collect elution in Eppendorf tubes.
[0139] HiS Cation Exchange Mini Column Protocol:
[0140] 1)Dilute sera in sample/running buffer;
[0141] 2)Add HiS resin to column and remove any air bubbles;
[0142] 3)Add UF water to aid in column packing;
[0143] 4)Add sample/running buffer to equilibrate column for sample loading;
[0144] 5)Add diluted sera to column;
[0145] 6)Collect all flow through fractions in Eppendorf tubes until level is at resin;
[0146] 7)Add sample/running buffer to wash column;
[0147] 8)Add elution buffer and collect elution in Eppendorf tubes.
[0148] Illustrative of the various buffering compositions useful in this technique are:
[0149] Sample/Running buffers: including but not limited to Bicine buffers of various molarities, pH's, NaCl content, Bis-Tris buffers of various molarities, pH's, NaCl content, Diethanolamine of various molarities, pH's, NaCl content, Diethylamine of various molarities, pH's, NaCl content, Imidazole of various molarities, pH's, NaCl content, Tricine of various molarities, pH's, NaCl content, Triethanolamine of various molarities, pH's, NaCl content, Tris of various molarities, pH's, NaCl content. Elution Buffer: Acetic acid of various molarities, pH's, NaCl content, Citric acid of various molarities, pH's, NaCl content, HEPES of various molarities, pH's, NaCl content, MES of various molarities, pH's, NaCl content, MOPS of various molarities, pH's, NaCl content, PIPES of various molarities, pH's, NaCl content, Lactic acid of various molarities, pH's, NaCl content, Phosphate of various molarities, pH's, NaCl content, Tricine of various molarities pH's, NaCl content.
[0150] Following tryptic digestion, additional processing may be carried out, for example:
[0151] Utilizing a type of micro-chromatographic column called a C18-ZIPTIP available from the Millipore company, the following preparatory steps were conducted.
[0152] 1. Dilute sera in sample buffer
[0153] 2. Aspirate and dispense ZIPTIP in 50% Acetonitrile
[0154] 3. Aspirate and dispense ZIPTIP in Equilibration solution
[0155] 4. Aspirate and dispense in serum sample
[0156] 5. Aspirate and dispense ZIPTIP in Wash solution
[0157] 6. Aspirate and dispense ZIPTIP in Elution Solution
[0158] Illustrative of the various buffering compositions useful in the present invention are:
[0159] Sample Buffers (various low pH's): Hydrochloric acid (HCl), Formic acid, Trifluoroacetic acid (TFA), Equilibration Buffers (various low pH's): HCl, Formic acid, TFA;
[0160] Wash Buffers (various low pH's): HCl, Formic acid, TFA; Elution Solutions (various low pH's and % Solvents): HCl, Formic acid, TFA;
[0161] Solvents: Ethanol, Methanol, Acetonitrile.
[0162] Spotting was then performed, for example upon a Gold Chip in the following manner:
[0163] 1. Spot 2 ul of sample onto each spot
[0164] 2. Let sample partially dry
[0165] As a result of these procedures, the disease specific markers namely proapo-A-I-protein having a molecular weight of about 1301.61 daltons and a sequence of THLAPYSDELR, apolipoprotein A-I precursor having a molecular weight of about 1188.58 daltons and a sequence of NLEKETEGLR, prealbumin/transthyrtin pre-albumin amyloidosis type I having a molecular weight of about 1366.7595 and a sequence of (R)GSPAINVAVHVFR(K) and a molecular weight of about 2450 and a sequence of ALGISPFHEHAEVVFTANDSGPR, fibrinogen gamma chain having a molecular weight of about 1683 daltons and a sequence of IHLISTQSAIPYALR, related to insulin resistance was found.
[0166] [0166]FIG. 1 is a photograph of a gel which is indicative of the presence/absence of the marker in disease vs. control and, in cases where the marker is always present, the relative strength, e.g. the up or down regulation of the marker relative to categorization of disease state is deduced.
[0167] A method for evidencing and categorizing at least one disease state is disclosed. The steps taken include obtaining a sample from a patient, preferably human, and conducting MS analysis on the sample. As a result, at least one biopolymer marker sequence or analyte thereof is isolated from the sample which undergoes evidencing and categorizing and is compared to the biopolymer marker sequence as disclosed in the present invention. The step of evidencing and categorizing is particularly directed to biopolymer markers or analytes thereof linked to at least one risk of disease development of the patient or related to the existence of a particular disease state.
[0168] In addition, various kits are contemplated for use by the present invention. One such kit provides for determining the presence of the disease specific biopolymer marker. At least one biochemical material is incorporated which is capable of specifically binding with a biomolecule which includes at least the disease specific biopolymer marker or analyte thereof, and a means for determining binding between the biochemical material and the biomolecule. The biochemical material for any of the contemplated kits, by way of example an antibody or at least one monoclonal antibody specific therefore, or biomolecule may be immobilized on a solid support and include at least one labeled biochemical material which is preferably an antibody. The sample utilized for any of the kits may be a fractionated or unfractionated body fluid or a tissue sample. Non-limiting examples of such fluids are blood, blood products, urine, saliva, cerebrospinal fluid, and lymph.
[0169] Further contemplated is a kit for diagnosing, determining risk-assessment, and identifying therapeutic avenues related to a disease state. This kit includes at least one biochemical material which is capable of specifically binding with a biomolecule which includes at least one biopolymer marker including the sequence of the particular disease specific biopolymer marker or an analyte thereof related to the disease state. Also included is a means for determining binding between the biochemical material and the biomolecule, whereby at least one analysis to determine a presence of a marker, analyte thereof, or a biochemical material specific thereto, is carried out on a sample. As previously described, analysis may be carried out on a single sample or multiple samples.
[0170] In accordance with various stated objectives of the invention, the skilled artisan, in possession of the specific disease specific marker as instantly disclosed, would readily carry out known techniques in order to raise purified biochemical materials, e.g. monoclonal and/or polyclonal antibodies, which are useful in the production of methods and devices useful as point-of-care rapid assay diagnostic or risk assessment devices as are known in the art.
[0171] The specific disease markers which are analyzed according to the method of the invention are released into the circulation and may be present in the blood or in any blood product, for example plasma, serum, cytolyzed blood, e.g. by treatment with hypotonic buffer or detergents and dilutions and preparations thereof, and other body fluids, e.g. CSF, saliva, urine, lymph, and the like. The presence of each marker is determined using antibodies specific for each of the markers and detecting specific binding of each antibody to its respective marker. Any suitable direct or indirect assay method may be used to determine the level of each of the specific markers measured according to the invention. The assays may be competitive assays, sandwich assays, and the label may be selected from the group of well-known labels such as radioimmunoassay, fluorescent or chemiluminescence immunoassay, or immunoPCR technology. Extensive discussion of the known immunoassay techniques is not required here since these are known to those of skilled in the art. See Takahashi et al. (Clin Chem 1999;45(8):1307) for a detailed example of an assay.
[0172] A monoclonal antibody specific against the disease marker sequence isolated by the present invention may be produced, for example, by the polyethylene glycol (PEG) mediated cell fusion method, in a manner well-known in the art.
[0173] Traditionally, monoclonal antibodies have been made according to fundamental principles laid down by Kohler and Milstein. Mice are immunized with antigens, with or without, adjuvants. The splenocytes are harvested from the spleen for fusion with immortalized hybridoma partners. These are seeded into microtiter plates where they can secrete antibodies into the supernatant that is used for cell culture. To select from the hybridomas that have been plated for the ones that produce antibodies of interest, the hybridoma supernatants are usually tested for antibody binding to antigens in an ELISA (enzyme linked immunosorbent assay) assay. The idea is that the wells that contain the hybridoma of interest will contain antibodies that will bind most avidly to the test antigen, usually the immunizing antigen. These wells are then subcloned in limiting dilution fashion to produce monoclonal hybridomas. The selection for the clones of interest is repeated using an ELISA assay to test for antibody binding. Therefore, the principle that has been propagated is that in the production of monoclonal antibodies the hybridomas that produce the most avidly binding antibodies are the ones that are selected from among all the hybridomas that were initially produced. That is to say, the preferred antibody is the one with highest affinity for the antigen of interest.
[0174] There have been many modifications of this procedure such as using whole cells for immunization. In this method, instead of using purified antigens, entire cells are used for immunization. Another modification is the use of cellular ELISA for screening. In this method instead of using purified antigens as the target in the ELISA, fixed cells are used. In addition to ELISA tests, complement mediated cytotoxicity assays have also been used in the screening process. However, antibody-binding assays were used in conjunction with cytotoxicity tests. Thus, despite many modifications, the process of producing monoclonal antibodies relies on antibody binding to the test antigen as an endpoint.
[0175] The purified monoclonal antibody is utilized for immunochemical studies.
[0176] Polyclonal antibody production and purification utilizing one or more animal hosts in a manner well-known in the art can be performed by a skilled artisan.
[0177] Another objective of the present invention is to provide reagents for use in diagnostic assays for the detection of the particularly isolated disease specific marker sequences of the present invention.
[0178] In one mode of this embodiment, the marker sequences of the present invention may be used as antigens in immunoassays for the detection of those individuals suffering from the disease known to be evidenced by said marker sequence. Such assays may include but are not limited to: radioimmunoassay, enzyme-linked immunosorbent assay (ELISA), “sandwich” assays, precipitin reactions, gel diffusion immunodiffusion assay, agglutination assay, fluorescent immunoassays, protein A or G immunoassays and immunoelectrophoresis assays.
[0179] According to the present invention, monoclonal or polyclonal antibodies produced against the disease specific marker sequence of the instant invention are useful in an immunoassay on samples of blood or blood products such as serum, plasma or the like, cerebrospinal fluid or other body fluid, e.g. saliva, urine, lymph, and the like, to diagnose patients with the characteristic disease state linked to said marker sequence. The antibodies can be used in any type of immunoassay. This includes both the two-site sandwich assay and the single site immunoassay of the non-competitive type, as well as in traditional competitive binding assays.
[0180] Particularly preferred, for ease and simplicity of detection, and its quantitative nature, is the sandwich or double antibody assay of which a number of variations exist, all of which are contemplated by the present invention. For example, in a typical sandwich assay, unlabeled antibody is immobilized on a solid phase, e.g. microtiter plate, and the sample to be tested is added. After a certain period of incubation to allow formation of an antibody-antigen complex, a second antibody, labeled with a reporter molecule capable of inducing a detectable signal, is added and incubation is continued to allow sufficient time for binding with the antigen at a different site, resulting with a formation of a complex of antibody-antigen-labeled antibody. The presence of the antigen is determined by observation of a signal which may be quantitated by comparison with control samples containing known amounts of antigen.
[0181] Antibodies may also be utilized against the disease specific markers, as haptens, to create an antibody response against the protein to which it binds, thereby identifying targets for treatment of the disease or a sub-class thereof.
[0182] Lastly, the markers and associated antibodies provide a tool for monitoring the progress of a patient during a therapeutic treatment, so as to determine the usefulness of a novel therapeutic agent.
[0183] All patents and publications mentioned in this specification are indicative of the levels of those skilled in the art to which the invention pertains. All patents and publications are herein incorporated by reference to the same extent as if each individual publication was specifically and individually indicated to be incorporated by reference.
[0184] It is to be understood that while a certain form of the invention is illustrated, it is not to be limited to the specific form or arrangement herein described and shown. It will be apparent to those skilled in the art that various changes may be made without departing from the scope of the invention and the invention is not to be considered limited to what is shown and described in the specification and drawings/figures.
[0185] One skilled in the art will readily appreciate that the present invention is well adapted to carry out the objectives and obtain the ends and advantages mentioned, as well as those inherent therein. The oligonucleotides, peptides, polypeptides, biologically related compounds, methods, procedures and techniques described herein are presently representative of the preferred embodiments, are intended to be exemplary and are not intended as limitations on the scope. Changes therein and other uses will occur to those skilled in the art which are encompassed within the spirit of the invention and are defined by the scope of the appended claims. Although the invention has been described in connection with specific preferred embodiments, it should be understood that the invention as claimed should not be unduly limited to such specific embodiments. Indeed, various modifications of the described modes for carrying out the invention which are obvious to those skilled in the art are intended to be within the scope of the following claims. | The instant invention involves the use of a combination of preparatory steps in conjunction with mass spectroscopy and time-of-flight detection procedures to maximize the diversity of biopolymers which are verifiable within a particular sample. The cohort of biopolymers verified within such a sample is then viewed with reference to their ability to evidence at least one particular disease state; thereby enabling a diagnostician to gain the ability to characterize either the presence or absence of said at least one disease state relative to recognition of the presence and/or the absence of said biopolymer, predict disease risk assessment, and develop therapeutic avenues against said disease. | 8 |
BACKGROUND OF THE INVENTION
This invention relates to plant supports. In particular, the present invention relates to a plant support having a helically coiled support member rigidly fastened to a plurality of legs.
Agricultural production of some species of flora (tomatoes, grapes, cucumbers, etc.) can be increased when the plants are provided with a support structure. In particular, plants that yield heavy fruitation but tend to have relatively weak stems and branches are prone to breakage in high winds and heavy rains. In some species, such as tomatoes, even if breakage does not occur, heavy yield losses can occur when branches bend and place the fruit in contact with the ground where it spoils.
Plant support structures can further improve yields by guiding plant growth upwards and reducing spreading, thus allowing more plants to be grown in a given area. This is particularly true of vines such as grapes and cucumbers.
Thus, plant supports can serve both to guide plant growth in a desired direction and help prevent losses due to breakage and spoiling. Smith U.S. Pat. No. 2,577,373 has also noted that the base of a plant support can improve yields by delineating a boundary and preventing overly close cultivation and irrigation furrowing which results in root damage.
The prior art includes Bork U.S. Pat. No. 4,860,489, which discloses a cylindrically-shaped plant support composed of two stakes to which a helical spring can be adjustably mounted. However, the Bork reference discloses a relatively expensive device composed of seven individually manufactured subcomponents. The competitive nature of agricultural production precludes overly costly support structures such as the one disclosed in the Bork reference.
Other examples of prior art include Smith U.S. Pat. No. 2,577,373 and Rinker U.S. Pat. No. 2,083,526. Both Smith and Rinker disclose plant supports, the body of which consists solely of helically wound springs. While inexpensive to manufacture, these configurations suffer from excessive flexibility. The lack of rigidity disclosed in both the Smith and Rinker references can result in plant breakage under high wind load conditions.
Finally, Binyon U.S. Pat. No. 3,239,171, Balousek U.S. Pat. No. 2,000,911 and Richards U.S. Pat. No. 417,838 all disclose plant supports composed of a single central stake to which bent wires and some variant of a spiral or helical shape have been attached. One problem with this configuration is that wind induced oscillations can easily cause the stake to work loose from the ground, eventually offering the plant little or no support. Another problem with the central stake is that its insertion can cause root damage (a problem also inherent in the Rinker reference).
SUMMARY OF THE INVENTION
The present invention is a plant support comprised of a plurality of legs around which a helically coiled member is wrapped. One end of the helically coiled member is shaped into a lower ring and welded to each leg. The other end of the coiled member is formed into an upper ring and also welded to each leg. Finally, the coiled member is welded to each leg at each coil-to-leg contact point between the lower ring end and the upper ring end. Each leg projects below the lower ring for insertion into the ground.
In addition to having good structural integrity, the present invention can be easily manufactured using automatic machinery. The simplicity of design which allows this automatic manufacture offers a significant cost saving over the prior art. Finally, when the lower ring is smaller than the upper ring, the resulting conical shape allows nesting of multiple plant supports into one another for space savings during transport and storage.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a first preferred embodiment of the present invention.
FIG. 2 is a perspective view of a second preferred embodiment of the present invention.
FIG. 3 is a perspective view of a third preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 illustrates a first embodiment of plant support 10, which includes lower section 12 and upper section 14. A plurality of substantially straight legs 16 are positioned equidistantly about the periphery of the generally conically-shaped structure of plant support 10. Straight legs 16 extend from the top of the upper section 14 to lower section 12, where they project out and provide means for anchoring the plant support into the ground.
Upper section 14 incorporates helically coiled member 18 welded to straight legs 16. The lower end of helically coiled member 18 is formed into smaller lower ring 20. The upper end of helically coiled member 18 is formed into larger upper ring 22.
Straight legs 16 are welded to both lower ring end 20 and upper ring end 22 of helically coiled member 18. Straight legs 16 can also be welded to the central portion of helically coiled member 18 between lower ring end 20 and upper ring 22 at each point of leg-to-coil contact.
Plant support 10 is formed from steel coil stock ranging in diameter from, for example, 0.120 inches to 0.148 inches (11 gauge to 9 gauge). The coil stock is purchased from a steel mill and comes as a continuous length of wire wrapped around a tube or wood frame called a "stem."
Plant support 10 is particularly suited for manufacture using automatic machinery. During production, three or more legs are fed to a suitable fixture either from one coil, or all at once from several coils.
After the legs are fed into the fixture and secured, they are cut to length automatically. The helically coiled member 18 is then wrapped around straight legs 16 and simultaneously welded as it is wrapped. Wrapping and welding of the helically coiled member 18 can be undertaken either from the smaller lower ring 20 end to the larger upper ring 22 end or vice versa.
The legs 16 secured in the fixture are rotated to facilitate wrapping and welding of the helically coiled member 18. The spacing of the helically coiled member's coils is controlled either by indexing of the legs and holding the spiral feed in place, or by indexing the spiral feed and holding the legs in place as they rotate.
Automatic production of plant support 10 also preferably entails automatic removal of the completed plant support structure from the production fixture and insertion of plant supports into one another, forming a bundle of, for example, twenty-five supports. Finally, the bundles are tied and labelled automatically.
Plant support 10 made in accordance with the second preferred embodiment of the present invention is shown in FIG. 2. The embodiment shown in FIG. 2 is essentially similar to the embodiment shown in FIG. 1, except for the addition of bends 24 in legs 16. Similar reference numerals are used to designate similar elements. Bends 24 act to enhance anchoring of plant support 10 in the ground when the portions of legs 16 comprising lower section 12 are inserted into the ground.
Plant support 10 made in accordance with the third preferred embodiment of the present invention is shown in FIG. 3. The embodiment shown in FIG. 3 is essentially similar to the embodiment shown in FIG. 1, except that legs 16 project beyond upper ring 22 of helically coiled member 18. The projections 26 can be straight or bent (as shown) to provide additional tying space for the upper portions of a tall plant or for decorative purposes.
The additional features shown in the embodiments of FIGS. 2 and 3 can be combined in the same plant support. The plant support need not be conical but can, for example, be cylindrical or hour-glass shaped. If conical, the plant support taper towards the top rather than narrowing toward the bottom, as shown in FIGS. 1-3. Finally, the plant support of the present invention can have less or more than the three legs shown in the preferred embodiments of the present invention.
Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention. | A plant support comprising a plurality of substantially straight legs surrounded by and welded to a helically coiled support member is disclosed. The plant support of the present invention offers the advantages of good structural rigidity combined with simplicity of design well suited for low-cost automated manufacturing methods. | 0 |
BACKGROUND OF THE INVENTION
1. Field Of The Invention
The present invention relates generally to the joint between articulated slats of the type which might be used in a retractable awning to conceal the awning and protect the same from environmental elements and more particularly to a system for sealing the joints between adjacent slats to prevent the leakage of water therethrough.
2. Description of the Prior Art
Retractable awnings have been utilized for many years, particularly as awnings for windows or entry doors of building structures. The awnings are typically rolled out during daylight hours to block undesired sun rays and rolled in at night when the sun has gone down. Such awnings normally include a roll bar which is mounted in a movable manner along an outer edge of the awning sheet so as to roll away from and back to the building as the awning is extended and retracted respectively.
More recently, retractable awning have also been mounted on the sides of mobile homes, recreational vehicles, travel trailers or the like. These newer versions of the retractable awning normally include support posts for supporting the outer edge of the awning sheet either by forming a brace from a side wall of the vehicle or by forming a ground support.
A concern with all retractable awnings relates to deterioration of the awnings such as is caused by adverse weather elements or prolonged exposure to the sun. Accordingly, when the awnings are retracted into a nonuse position, it is not uncommon to provide a strip of weather retardant fabric or rubberized material adjacent the inner edge of the awning sheet so that when the awning sheet is completely rolled into its retracted position, the weather retardant material will surround the remaining portion of the awning sheet thereby protecting the awning sheet from adverse environmental elements and ultraviolet radiation from the sun. Some retractable awnings of the type mounted on recreational vehicles and the like have even been mounted in metallic boxes so that the box can be closed to seal the awning therein when not in use.
A more recent development adapted to protect an awning from environmental elements when the awning is not in use utilizes a plurality of elongated slats, usually of aluminum, which are pivotally connected together along their length in an articulated manner so as to envelope or encapsulate the awning when it is rolled into its retracted position. The articulated slats take the place of the weather-retardant fabric materials which have been used previously, but one problem with the articulated slats is that the joints between adjacent slats are not water tight. Accordingly, rain water and the like will typically seep between adjacent slats and leak underneath the awning in an undesired manner.
One system which addresses the problem of seepage is disclosed in U.S. Pat. No. 4,634,172 issued to Henry J. Duda on Jan. 6, 1987, and entitled FLEXIBLE HINGE RAIN SEALING MECHANISM. This mechanism is only useful in connecting the innermost slat to the side of the vehicle and does so by utilizing a connection strap made of a flexible material which is seated in opposing C-shaped grooves provided in a mounting rail on the vehicle wall and the innermost slat. The flexible strap cooperates with the metal material on the mounting rail and the slat to effect a water-tight seal when a stress is placed on the joint. Such a system for making a joint water tight is not useful between adjacent articulated slats but is only useful at the juncture of one of those slats with the mounting rail on the vehicle wall.
Accordingly, it is a primary object of the present invention to provide a system for establishing a water-tight seal between adjacent articulated members.
It is another object of the present invention to provide a water-tight seal between elongated metallic slats which are pivotally innerconnected by a tongue-in-groove type connection.
It is a further object of the present invention to provide a system for establishing a water-tight seal between articulated slats that are utilized along one edge of a retractable awning to conceal the awning by encapsulating such when it is moved into its retracted position.
SUMMARY OF THE INVENTION
The present invention in general concerns a water-tight sealing system for use with pivotally connected or articulated members and more particularly to the use of such a sealing system with the articulated slats which are used to encase a retractable awning when the awning is in its retracted or nonuse position.
When retractable awnings are not in use, they are usually rolled up adjacent a surface upon which they are supported. To prevent the awning fabric from deteriorating as a result of exposure to adverse environmental conditions or the sun, some such awnings are encapsulated in their retracted position in a metal sleeve composed of a plurality of pivotally interconnected slats. Such slats form a generally cylindrical body in which the awning canopy can be retained and protected in a rolled up condition. The slats are typically made of a rigid material, such as aluminum, with each slat having a male connection element on one longitudinal edge and a mating female connection element along the opposite longitudinal edge so that the male element of one slat can be pivotally received in the female element of an adjacent slat. With the slats so interconnected, they can be wrapped around the roll bar and canopy of the retractable awning. Normally the pivotally connected or articulated slats form an extension or connector between the supporting surface for the retractable awning and the canopy or awning sheet itself. In other words, one of the articulated slats is operably connected to the supporting surface while the most distant articulated slat is connected to the awning sheet whereby subsequent to the awning sheet being wrapped around the roll bar, the articulated slats will wrap around the roll bar and awning sheet as the roll bar and sheet approach the supporting surface.
The present invention for establishing a water-tight seal along the joint between adjacent slats utilizes a resilient sealing strip to bridge the space existing between the male and female elements of joined articulated slats. The sealing system establishes a water-tight barrier along the joint to prevent water from seeping through the joint in an undesired manner. In the preferred embodiment described hereinafter, the male and female elements define channels of generally C-shaped transverse cross-section whereby the male element can receive and retain the resilient strip in a manner such that it protrudes away therefrom into compressive, sliding engagement with the female element to establish the desired water-tight seal.
Other aspects, features and details of the present invention can be more completely understood by reference to the following detailed description of a preferred embodiment, taken in conjunction with the drawings, and from the appended claims.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a fragmentary perspective view of a retractable awning in its extended position utilizing the sealing system of the present invention.
FIG. 2 is a fragmentary perspective view similar to FIG. 1 with the awning shown in a retracted position.
FIG. 3 is an enlarged section taken along line 3--3 of FIG. 2.
FIG. 4 is an enlarged fragmentary section taken along line 4--4 of FIG. 1.
FIG. 5 is a further enlarged transverse section taken through a joint between adjacent articulated slats forming a part of the retractable awning of FIG. 1.
FIG. 6 is an enlarged fragmentary perspective view of the resilient sealing strip utilized in the sealing system of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring first to FIGS. 1 and 2, a retractable awning 10 incorporating the sealing system of the present invention is illustrated and includes a pair of support arms 12 (only one being seen), a pair of brace members 14 (only one being seen), a roll bar 16 rotatably mounted on the distal ends of the support arms 12, an awning sheet or canopy 18 connected along an outer edge 20 to the roll bar 16 and having its inner edge 22 operably connected to the side of a support surface 24 through a plurality of articulated slats 26.
The support arms 12 have a lower end pivotally connected to lower support brackets 28 mounted on the support surface 24, while the brace members 14 have upper ends pivotally connected to upper brackets 30 on the support surface. The opposite or lower end 32 of each brace member is slidably received in an associated support arm for movement along the length thereof. With this arrangement, the awning can be moved between the extended position of FIG. 1 and the retracted position of FIG. 2.
The awning sheet 18 is attached to the roll bar 16 in any conventional manner but in the disclosed embodiment of the awning, the roll bar is of elongated cylindrical configuration having a plurality of grooves 34 of C-shaped cross-section formed in the surface thereof. The outer edge 20 of the awning sheet is hemmed to define a sleeve 36 which is inserted into one of the C-shaped grooves 34 in the roll bar and it is retained therein by inserting a rod or other tubular member 38 through the sleeve. The rod 38 has a diameter of sufficient size to be retained in the C-shaped groove. Similarly, a valence 40 might be attached to the roll bar in an identical manner as is illustrated in FIGS. 1 and 3.
The articulated slats 26 which form an extension from the support surface 24 and a means for connecting the awning sheet to the support surface are best illustrated in FIGS. 3 and 4. Each slat is identical and may be made of a fairly rigid material such as aluminum. The slats are elongated and of a length equal to the width of the awning sheet 18 and are slightly arcuate in transverse cross-section. Each slat has a bead or male connection element 42 along one edge and a mating female connection element 44 along the opposite edge so that the male connection element of one slat can be inserted into the female connection element of an adjacent slat to form an articulated tongue-in-groove type joint between the slats.
As best illustrated in FIG. 5, the male connection element 42 projects substantially perpendicularly away from the concave side of the slat and has a groove 46 of generally C-shaped cross-section extending along its length. The groove 46 defines a relatively narrow slot 48 along the length of the male element with the slot 48 opening away from the concave side of the slat. The female element 44 which extends along the opposite edge of the slat also extends away from the concave side of the slat and has a groove 50 of C-shaped cross-section formed therein. The C-shaped groove 50, however, opens through a slot 52 that faces the opposite direction from the slot 48 in the male element.
The male element 42 has a larger diameter than the width of the slot 52 in the female element 44 so that the male element can be pivotally received and retained in the groove 50 of the female element of an adjacent slat. Of course, the male element is inserted into the female element longitudinally for purposes of connecting adjacent slats.
A sealing strip 54, which is best illustrated in FIGS. 5 and 6, is fabricated from a resilient material such as rubber and includes a cylindrical main body portion 56 having a leg 58 of generally rectangular transverse cross-section forming a radial projection from the main body. The diameter of the main body 56 is slightly smaller than the diameter of the C-shaped groove 46 in the male element 42 but is larger than the slotted opening 48 in the male element so that the resilient strip can be retained in the male element with the rectangular leg 58 projecting away therefrom toward the confronting inner surface 60 of the C-shaped groove 50 in the female element. The length of the leg 58 is such that it will engage the inner surface 60 of the female element and form a water-tight seal therewith when adjacent interconnected slats are fully articulated in one direction or another but will not engage the surfaced 60 at an intermediate position of the two slats. In other words, when adjacent slats are fully articulated in one direction as when the awning is fully extended, the leg 58 engages the surface 60 and when adjacent slats are fully articulated in the opposite direction as when the awning is fully retracted, the leg 58 engages the surface 60. However, at an intermediate position between the extended and retracted positions of the awning, the leg 58 does not engage the surface 60 to facilitate assembly of a joint between articulated slats. At the intermediate position, since there is no engagement between the sealing strip and the female element, the strip can be easily inserted longitudinally into a male element, or if previously inserted into the male element, the male element will easily slide into the female element so that assemblage of adjacent slats is accomplished in a simple and efficient manner.
As will be appreciated and as illustrated in FIG. 4, the outermost edge of the outermost slat 26 utilized in the awning has a female element 44 therealong and the inner edge 22 of the awing sheet is connected thereto. The connection of the awning sheet to the outermost slat 26 is made by inserting a hem along the inner edge of the awning sheet into the C-shaped groove 50 of the female element and thereafter inserting a rod or other tubular member 62 through the hem to retain the inner edge of the awning sheet in the female element of the outermost slat.
Similarly, the innermost edge of the innermost slat 26 utilized in the awning has a male element 42 extending therealong which is connected to a mounting rail 64 affixed to the supporting surface 24 by a joinder member 66. The mounting rail is an elongated rigid element that is affixed to the supporting surface in any suitable manner and has a downwardly and outwardly opening groove 68 of generally C-shaped cross-section. The joinder member 66 is an elongated bar of either rigid or flexible material that has a channel-shaped male member 70 along one edge and a channel-shaped female member 72 along the opposite edge. The channels 70 and 72 are of generally C-shaped cross-section with the male member 70 being adapted to fit within and be retained in the groove 68 provided on the mounting rail and the female member 72 adapted to receive and retain the male element 42 of the innermost slat 26. In order to establish a water-tight seal at this juncture, a resilient strip of the type disclosed in FIG. 6 can be inserted into the male element 42 of the innermost slat 26 and into the male member 70 of the joinder member 66.
In operating the awning, it will be appreciated in the extended position illustrated in FIG. 1 that the articulated slats 26 form an extension from the support surface 24 which is substantially coplanar with the awning sheet 18 itself. Each joint between articulated slats, of course, is sealed by the system disclosed herein so that water will not leak through the joints between adjacent articulated slats. The awning is moved to its retracted position of FIG. 2 by allowing the outermost end of the brace members 14 to slide inwardly along the length of the associated support arm 12 until the support arm is moved into a vertical orientation. As this occurs, the awning sheet 18 is wrapped around the roll bar 16 until the roll bar reaches the inner edge 22 of the awning sheet and thereafter, the roll bar along with the wrapped awning sheet are incapsulated by the articulated slats 26 which collapse and form a cylindrical protective case therearound. Of course, when the awning is again extended, the cylindrical case formed by the articulated slats opens up and extends away from the support surface. It should also be appreciated, however, that even when the awning is retracted, the sealing system of the present invention prevents water from passing through the joints between the articulated slats thereby avoiding possible water damage to the awning sheet which is encased therein.
Although the present invention has been described with a certain degree of particularity, it is understood that the present disclosure has been made by way of example, and changes in detail or structure may be made without departing from the spirit of the invention, as defined in the appended claims. | A system for establishing a water-tight seal along a joint between articulated slats of the type which might be used along the inner edge of a retractable awning includes the use of male and female connection elements along opposite edges of the slats and a resilient strip of material bridging the space between connected male and female elements to prevent the passage of water through the joint. | 4 |
FIELD OF THE INVENTION
[0001] The present disclosure relates to the field of diving equipment and devices which may be used as a signaling device.
BACKGROUND OF THE INVENTION
[0002] Scuba (Self-Contained, Underwater Breathing Apparatus) diving is very popular, and the number of scuba divers is ever-increasing in a wide variety of fields: military, commercial, and recreational. A scuba system allows a diver to reach significant depths and remain underwater for extended periods of time, offering a major advantage over breath-holding divers. While a scuba diver's ability to reach lower depths for extended periods of time is an advantage, it also engenders a host of challenges. For example, a scuba diver may encounter obstacles in a body of water or on the floor of a body of water that he or she would not have encountered in a breath-holding dive. Further, most scuba gear does not allow a diver to communicate with another diver using his or her voice. In addition, illumination from both natural light and artificial light is obscured as a diver descends deeper in the water. As a result, a member of a group of divers may easily become lost and separated from the group.
[0003] The diving industry has attempted to provide some basic solutions to some of these challenges. Some scuba divers may customarily carry a knife which could free a diver if he or she is caught in an obstacle. However, not all scuba divers carry a knife, and some obstacles may be too tough for a scuba diver to cut through. Likewise, scuba divers may communicate with each other using hand signals to overcome the lack of voice communication. However, scuba divers may not always be able to see each other due to poor visibility or not being in the same line of sight.
[0004] Beyond knives and hand signals, the diving industry has attempted to develop more sophisticated signaling devices. For example, a device known as the Scuba-Alert uses sound waves to signal other divers. The Scuba-Alert uses small pulses of compressed air to vibrate a steel disk and generate a “quacking” sound. However, devices like the Scuba-Alert rely on the inflator hose of a scuba system and draw air from the scuba diver's primary source of air in order to operate. This is but one deficiency with the Scuba-Alert and other products like it, which create further hazard because a diver may be in the most peril when his or her air supply is dangerously low.
[0005] Another signaling device is known as the Buddy Call. The Buddy Call is battery powered and uses electronics to generate a signal to other divers. However, the Buddy Call's performance is lacking in many respects. For example, since the Buddy Call is electronic, it has a signal range of only 100 feet and a working depth of up to 110 feet, yet scuba divers may reach depths beyond 110 feet and easily become stranded more than 100 feet from their partner or the nearest rescue source. Also, the Buddy Call is bulky and may not be conveniently located on a diver's suit or other equipment to be easily accessed in the event of an emergency. Finally, the Buddy Call also presents the hazard of not operating due to loss of battery power, which is often undetectable until the device is needed.
SUMMARY OF THE INVENTION
[0006] Therefore, it would be advantageous to have a more sophisticated signaling device which is independent of a scuba system, has a signal range beyond 100 feet, and a working depth of up to 250 feet. Other advantages over the prior art will become known upon review of the Summary of the Invention and Detailed Description and the appended claims.
[0007] In one embodiment of the present disclosure, an underwater signaling device uses its own independent source of pressurized gas to generate sound waves and gain the attention of other divers. The device may have a metal container for a body, and within the container a vessel may store pressurized gas as an independent source of pressurized gas. Because the pressurized gas is stored in a discrete vessel, the underwater signaling device does not tap into the regulator hose of a scuba system and draw air from a scuba diver's primary source of air. Therefore, unlike prior gas-operated signaling devices, the present disclosure operates regardless of the status of the scuba diver's regular air supply.
[0008] Further, the present disclosure generates sound waves which can be heard beyond 100 feet, and the present disclosure may operate to a working depth of up to 250 feet. In one embodiment, a puncture pin is located above the pressurized vessel, and a diver may activate a trigger mechanism to puncture the pressurized vessel, releasing the pressurized gas. In one embodiment of the present disclosure, a diver may activate the trigger mechanism by depressing a button located on top of the container such that the diver's own energy is pushing the puncture pin into the vessel. Once the vessel has been punctured, the pressurized gas flows upward and out of a tube which may extend laterally from the body of the container. Within this tube is a sounding device, such as a metal disk, which generates sound waves. The metal disk vibrates when the pressured vessel is punctured and generates sound waves as air moves past it. Beyond the tube, a frusto-conical element may be provided to amplify the sound waves so they may be heard by another diver who is over 100 feet away.
[0009] An embodiment of the present disclosure which uses metal materials may operate at increased depths. The container, vessel, and trigger mechanism may be constructed from a variety of metals. Therefore, the present disclosure could be operable to depths of up to 250 feet. This is a marked improvement in performance over electronic signal devices like the Buddy Call, which can only operate to a depth of up to 110 feet.
[0010] In a further embodiment, a light strobe or LED or other illumination source may be attached to the exterior of the container of the underwater signaling device. The same trigger mechanism which releases the pressurized gas from the vessel may also activate a light strobe to generate a light signal which complements the sound signal by way of a limit switch, presence sensor or other known input device. The light strobe may be useful in unexpected situations when the sound signal alone is insufficient to direct a second diver to the location of a distressed diver. For example, a second diver may not be able to easily locate a distressed diver if they are not in the same line of sight or there is poor visibility or if the sound signal is bouncing off rocks or coral in the vicinity of the diver, thereby creating an echo effect. The sound signal may alert the second diver and provide the second diver with a general direction where he or she may find the distressed diver. As the second diver travels toward the sound signal, the light strobe may help the second diver by providing a more precise location of the distressed diver.
[0011] In a similar vein, a GPS device may be used alone or with any embodiments of the present disclosure described herein, to provide an additional signal for other divers or a dive master or emergency personnel to find a distressed diver. The GPS device may provide a beacon which may be received by a divemaster located on a boat or land, as well as any other receiver which may received a GPS beacon such as a smart phone device. The receiver of such a signal may deploy a boat over the GPS beacon and deploy a diver.
[0012] In another embodiment of the disclosure, a diver may pull a rip cord to activate the trigger mechanism. In this embodiment, the trigger mechanism and puncture pin do not derive the energy to puncture the pressurized vessel from the user. Instead, a coiled spring rests behind the puncture pin. When a diver pulls the rip cord, the coiled spring is allowed to release, driving the puncture pin into the pressurized vessel and releasing the contents of the vessel.
[0013] Generally, the present disclosure may be attached to a diver in a variety of fashions. In one embodiment, an eyelet may be interconnected to the exterior wall of the container. A half-ring or any other connection component may be partially interconnected to the eyelet such that the ring or component may rotate freely. This eyelet-ring combination allows a diver to attach the present disclosure anywhere on a diver's buoyancy compensator.
[0014] Beyond eyelets, the present disclosure may be attached to a diver by other techniques, e.g. straps. A diver's gear may already provide straps such as the waist strap of the buoyancy compensator. Or the present disclosure may include straps which are independent of a diver's existing gear.
[0015] A person who is skilled in the art may appreciate techniques to attach the present disclosure to a diver beyond eyelets and straps. For example, the present disclosure may be integrated into a diver's suit. The present disclosure could be woven into a waist pouch.
[0016] In another embodiment of the present disclosure, the signaling device may interface with a device on a diver's arm such as a wrist clip, diving computer, amulet, diving watch, or any other component which may activate or send a communiqué to the present disclosure. In this embodiment, a diver may activate the signaling device using the same hand that has an additional device attached. Therefore, if a diver has one arm which is entangled or otherwise encumbered, then the diver may activate the present disclosure using his or her free arm which has a wrist clip, diving computer, amulet, diving watch, or any other component which may activate or send a communiqué to the present disclosure.
[0017] The Summary of the Invention is neither intended nor should it be construed as being representative of the full extent and scope of the present disclosure. The present disclosure is set forth in various levels of detail in the Summary of the Invention as well as in the attached drawings and the Detailed Description of the Invention and no limitation as to the scope of the present disclosure is intended by either the inclusion or non-inclusion of elements, components, etc. in this Summary of the Invention. Additional aspects of the present disclosure will become more readily apparent from the Detailed Description, particularly when taken together with the drawings.
[0018] The above-described benefits, embodiments, and/or characterizations are not necessarily complete or exhaustive, and in particular, as to the patentable subject matter disclosed herein. Other benefits, embodiments, and/or characterizations of the present disclosure are possible utilizing, alone or in combination, as set forth above and/or described in the accompanying figures and/or in the description herein below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the disclosure and together with the general description of the disclosure given above and the detailed description of the drawings given below, serve to explain the principles of the disclosures.
[0020] It should be understood that the drawings are not necessarily to scale. In certain instances, details that are not necessary for an understanding of the disclosure or that render other details difficult to perceive may have been omitted. It should be understood, of course, that the disclosure is not necessarily limited to the particular embodiments illustrated herein.
[0021] In the drawings:
[0022] FIG. 1 shows a side view of one embodiment of the present disclosure where the trigger mechanism is a depressible button.
[0023] FIG. 2 shows a side view of one embodiment of the present disclosure where the trigger mechanism is a rip cord selectively interconnected to a spring-loaded vertical component.
[0024] FIG. 3 is an isometric view of one embodiment of the present disclosure.
[0025] FIG. 4 is a side view of one embodiment of the present disclosure which demonstrates the generation of sound waves.
DETAILED DESCRIPTION
[0026] The subject of the present disclosure relates to an underwater signaling device which has advantages over gas-operated devices and electronic devices. In one embodiment of the present disclosure, the component materials are made of metal, which allows for greater resistance to water pressure as the depth of operation increases. However, a person who is skilled in the art may identify another material, or materials, which is advantageous for operation depth or other parameters.
[0027] As described in detail below, various embodiments of the present disclosure comprise a novel valve, further comprising an inlet connection and an outlet connection, each connection further comprising a horizontal and vertical adjustment means, and/or other features.
[0028] FIG. 1 is a side view of one embodiment of the present disclosure. The bottom side of the underwater signaling device 101 may begin with a substantially planar bottom wall 102 . A person who is skilled in the art may determine that it would be advantageous to have the bottom wall 102 be detachable in order to create a reusable underwater signaling device 101 .
[0029] The bottom wall 102 interconnects or selectively interconnects with at least one upwardly-extending lower wall 103 . Within a portion of this wall 103 is a vessel 110 which contains pressurized gas. This vessel 110 is advantageous because the source of air for the underwater signaling device 101 is independent of the diver's air supply. Further, the vessel 110 may be configured or designed to be punctured, releasing the pressurized gas.
[0030] Continuing upward, one particular embodiment of the present disclosure has an upwardly-extending, frusto-conical wall 104 interconnected to the at least one upwardly-extending lower wall 110 . The frusto-conical wall 104 tapers to a smaller diameter. At least one upwardly-extending upper wall 105 is interconnected with the frusto-conical wall 104 . Finally, a substantially planar top wall 106 is interconnected with the at least one upwardly-extending upper wall 105 .
[0031] The aforementioned elements of this particular embodiment of the present disclosure form a basic container of the underwater signaling device 101 which contains a vessel 110 for holding and selectively releasing a pressurized gas.
[0032] Various embodiments of the present disclosure may puncture the vessel 110 in order to release its pressurized gas. The trigger mechanism 115 with a puncture pin 118 is substantially positioned inside of the container and above the vessel 110 . A portion of the trigger mechanism 115 extends upward through an opening 107 in the top wall 106 such that a user may depress this extended portion to activate the trigger mechanism 115 . A guide plate 114 may keep the trigger mechanism substantially vertical, and the guide plate 114 provides a surface for the spring 116 to compress against. The spring 116 presents an upward force against the trigger mechanism 115 to keep the puncture pin 118 away from the vessel 110 before the trigger mechanism 115 is activated. When a user depresses the trigger mechanism 115 , the puncture pin 118 punctures the vessel 110 and releases the pressurized gas.
[0033] A laterally extending tube 111 is interconnected to at least one upwardly-extending upper wall 105 such that the tube 111 communicates with the interior of the underwater signaling device 101 . Within the tube 111 is a metal disk 113 or similar device which vibrates as pressurized gas rushes over it. When the pressurized gas is released from the vessel 110 , it rushes out of the laterally extending tube 111 . The vibrating metal disk 113 generates sound waves which travel out of the laterally extending tube 111 . A second, frusto-conical wall 112 may be interconnected to the laterally extending tube 111 . This frusto-conical wall 112 may amplify the sound waves generated by the vibrating metal disk 113 .
[0034] Various embodiments of the present disclosure may attach to a user's body or gear. An eyelet may be interconnected to the at least one upwardly-extending lower wall 103 . In this particular embodiment, a half ring 109 is partially interconnected with the eyelet 108 such that the half-ring may freely rotate. This half ring 109 may attach to the user or diver via a carabiner on the diver's gear.
[0035] In a further embodiment, a person who is skilled in the art may appreciate additional components to the underwater signaling device 101 which enhance or complement the devices' audible signal. For example, an embodiment of the present disclosure may have a light strobe which is interconnected to the at least one upwardly-extending lower wall 103 . A light strobe may be an advantageous complement to the audible signal since a second diver may not be able to immediately locate the distressed diver with the audible signal. A light strobe component would help a second diver precisely locate a distressed diver.
[0036] In yet another embodiment of the present disclosure, a GPS device may be used alone, or with any embodiments of the present disclosure provided herein, to provide an additional signal for other divers to find a distressed diver. The GPS device may be interconnected to the first upwardly-extending wall 103 of the underwater signaling device 101 . The GPS device may provide a beacon which may be received by a divemaster located on a boat or land, as well as any other receiver which may received a GPS beacon such as a smart phone device. The receiver of such a signal may deploy a boat over the GPS beacon and deploy a diver.
[0037] FIG. 2 shows a side view of a further embodiment of the present disclosure. Here, a user activates the trigger mechanism 115 by pulling a rip cord 117 , not depressing a button. The trigger mechanism 115 has a portion extending through the opening 107 in the top wall 106 . A rip cord 117 secures this extended portion of the trigger mechanism 115 in place. In this static position a spring 116 is coiled inside of the underwater signaling device 101 between the top wall 106 and a lateral portion of the trigger mechanism 115 . When a user pulls the rip cord 117 , the spring 116 is allowed to drive the trigger mechanism 115 and its puncture pin 118 into the vessel 110 , releasing pressurized gas.
[0038] FIG. 3 shows an isometric view of one embodiment of the present disclosure. In this embodiment the trigger mechanism 115 is a depressible button. FIG. 4 shows a side view of one embodiment of the present disclosure where the trigger mechanism 115 is a depressible button. This figure demonstrates how the present disclosure projects sound waves.
[0039] The foregoing description of the present disclosure has been presented for illustration and description purposes. However, the description is not intended to limit the invention to only the forms disclosed herein. In the foregoing Detailed Description for example, various features are grouped together in one or more embodiments for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the following claims are hereby incorporated into this Detailed Description, with each claim standing on its own as a separate preferred embodiment of the invention.
[0040] As used herein, “at least one,” “one or more,” and “and/or” are open-ended expressions that are both conjunctive and disjunctive in operation. For example, each of the expressions “at least one of A, B and C,” “at least one of A, B, or C,” “one or more of A, B, and C,” “one or more of A, B, or C” and “A, B, and/or C” means A alone, B alone, C alone, A and B together, A and C together, B and C together, or A, B and C together.
[0041] Consequently, variations and modifications commensurate with the above teachings and skill and knowledge of the relevant art are within the scope of the present invention. The embodiments described herein above are further intended to explain best modes of practicing the invention and to enable others skilled in the art to utilize the invention in such a manner, or include other embodiments with various modifications as required by the particular application(s) or use(s) of the present invention. Thus, it is intended that the claims be construed to include alternative embodiments to the extent permitted by the prior art. | An underwater signaling device which has an independent source of pressurized gas can operate regardless of the status of a scuba diver's air source. The underwater signaling device produces a sound signal which may be heard beyond 100 feet, and the present disclosure may operate to depths of up to 250 feet. Further, the present disclosure may be supplemented by light strobe and/or GPS devices, which allow another diver to precisely locate a distressed diver. A diver may activate the present disclosure by depressing a button or by pulling a rip cord or other methods. In one embodiment, the present disclosure allows replacement of the independent source of pressurized gas, making the present disclosure reusable. | 6 |
This is a division of Ser. No. 312,153, filed 2/21/89.
BACKGROUND OF THE INVENTION
The present invention relates to novel substituted quinolinecarboxylic acid derivatives having antibacterial activity.
Since the introduction of nalidixic acid in 1963, a considerable number of patents and scientific papers have been published on compounds having a 1-substituted-1,4 dihydro-4-oxopyridine-3-carboxylic moiety, collectively known as quinolone. Many of these compounds have been shown to have significant antibacterial activity. The structure - activity relationship of quinolone compounds has been reviewed by Schentaget al., Res. Clin. Forums, 7, (2), 9(1985).
At one time it Was believed that substitution at the C-2 position of a substituted quinoline carboxylic acid led to inactive compounds, Metscher et al., J. Med. Chem. 21, 485(1978). However, U.S. Pat. No. 4,426,381 to Matsumura et al., discloses a compound having a thiazoline moiety connecting the C-2 substituent to the N-1 position. This compound Was shown to have good antibacterial activity. Additionally, Chu et al., J. Heterocyclic Chem., 24, 1537(1987) discloses compounds where the C-2 and N-1 positions are bridged by an alkylene chain. The compounds of the present invention comprise novel improvements in which the C-2 and N-1 positions are bridged by an aromatic substituent.
SUMMARY OF THE INVENTION
The present invention relates to new compounds represented by formula I: ##STR2## wherein R 1 is hydrogen, alkali metal, alkaline earth metal or lower alkyl; R 2 is hydrogen, benzyl or alkyl(C 1 -C 3 ); X is hydrogen or fluoro; and when R 1 is hydrogen, the pharmacologically acceptable salts thereof.
Furthermore this invention is concerned with novel compounds represented by the formula II useful for the preparation of compounds of formula I above: ##STR3## wherein R 1 and X are as defined hereinabove.
In addition, this invention is concerned with novel compounds of formula III. ##STR4## wherein R 1 and X are as defined hereinabove.
DESCRIPTION OF THE INVENTION
The compounds of the present invention may be prepared according to the following reaction scheme.
SCHEME ##STR5##
According to the foregoing scheme, ethyl 2-pyridyl aoetate 1 is reacted with lithium bis(trimethylsilyl)amide in tetrahydrofuran at -5° C. The mixture is added to acid chloride 2 wherein X is as described above, at -5° C. giving ethyl ester 3. Intermediate 3 is reacted With a substituted piperazine wherein R 2 is as described above in N,N dimethylformamide, pyridine or 1-methyl-2-pyrrolidinone at 110° C. giving compound 4. Compound 4 is hydrolyzed with alkali base or acid giving carboxylic acid 5. Also, compound 4 is catalytically reduced with hydrogen using 10% palladium-on-carbon in trifluoroacetic acid giving derivative 6. Ethyl ester 3, wherein X is as described above, is also catalytically reduced with hydrogen using 10% palladium-on-carbon in trifluoroacetic acid giving derivative 7.
The compounds of the present invention are active antibacterial agents as established in the following in vitro tests. As such they are effective in treating bacterial infections in warm-blooded animals.
The in vitro antimicrobial spectrum of the compounds of the invention were determined by the agar plate dilution method with Mueller-Hinton agar and an inoculum of each test organism of approximately 10 4 colony forming units delivered by the steers replicating device. The minimal inhibitory concentration (MIC) in mcg/ml is defined as the lowest concentration of test compound that inhibited visible growth after 18 hours incubation at 35° C. Results with the test compound described in Example 6 are given in Table I.
TABLE 1______________________________________In vitro Antibacterial Spectrum Compound Described In Example No. 6Organism and No. MIC (mcg/ml)______________________________________Escherichia coli MOR 84-20 2Escherichia coli VGH 84-19 4Escherichia coli CMC 84-50 2Klebsiella oneumoniae CMC 84-31 8Klebsiella nneumoniae MOR 84-24 8Klebsiella nneumoniae IO 83-5 8Enterobacter cloacae VGH 84-39 2Enterobacter cloacae K 84-10 2Enterobacter cloacae MOR 84-30 16Serratia marcescens MOR 84-41 2Serratia marcescens CMC 83-74 >16Serratia marcescens IO 83-63 4Morganella morganii VGH 84-12 4Morganella morganii CMC 84-38 0.5Moroanella morganii MOR 84-45 0.5Proteus rettgeri IO 83-21 1Providencia stuartii CMC 83-3 >16Citrobacter diversus K 82-24 4Pseudomonas aeruginosa K 84-16 >16Pseudomonas aeruginosa VGH 84-3 >16Pseudomonas aeruginosa CMC 83-20 >16Staphylococcus aureus VGH 84-47 >16Staphylococcus aureus K 82-26 >16Staphylococcus aureus CMC 83-131 >16Staphylococcus aureus ATCC 25913 >16Streptococcus faecalis VCI 85-30 >16Streptococcus faecalis VGH 84-69 >16Streptococcus faecalis CMC 83-120 >16Escherichia coli ATCC 25922 4Escherichia coli D 21 4Escherichia coli D 22 2______________________________________
When the compounds are employed for the above utility, they may be combined with one or more pharmaceutically acceptable carriers, for example solvents, diluents and the like, and may be administered orally in such forms as tablets, capsules, dispersible powders, granules, or suspensions containing, for example, from about 0.05 to 5% of suspending agent, syrups containing, for example, from about 10 to 50% of sugar, and elixirs containing, for example, from about 20 to 50% ethanol, and the like, or parenterally in the form of sterile injectable solutions or suspensions containing from about 0.05 to 5% suspending agent in an isotonic medium. Such pharmaceutical preparations may contain, for example, from about 0.05 up to about 90% of the active ingredient in combination with the carrier, more usually between about 5% and 60% by weight.
The effective dosage of active ingredient employed may vary depending on the particular compound employed, the mode of administration and the severity of the condition being treated. However, in general, satisfactory results are obtained when the compounds of the invention are administered at a daily dosage of from about 2 to about 100 mg/kg of animal body weight, preferably given in divided doses two to four times a day, or in sustained release form. For most large mammals the total daily dosage is from about 100 to 750 mg, preferably from about 100 to 500 mg. Dosage forms suitable for internal use comprise from about 100 to 750 mg of the active compound in intimate admixture with a solid or liquid pharmaceutically acceptable carrier. This dosage regimen may be adjusted to provide the optimal therapeutic response. For example, several divided doses may be administered daily or the dose may be proportionally reduced as indicated by the exigencies of the therapeutic situation.
A decided practical advantage is that these active compounds may be administered orally as well as by intravenous, intramuscular, or subcutaneous routes. Solid carriers include starch, lactose, dicalcium phosphate, microcrystalline cellulose, sucrose and kaolin, while liquid carriers include sterile water, polyethylene glycols, non-ionic surfactants and edible oils such as corn, peanut and sesame oils, as are appropriate to the nature of the active ingredient and the partioular form of administration desired. Adjuvants customarily employed in the preparation of pharmaceutical compositions may be advantageously included, such as flavoring agents, coloring agents, preserving agents, and antioxidants, for example, vitamin E, ascorbic acid, BHT and BHA.
The preferred pharmaceutioal compositions from the stand-point of ease of preparation and administration are solid compositions, particularly tablets and hard-filled or liquid-filled capsules. Oral administration of the compounds is preferred.
These active compounds may also be administered parenterally or intraperitoneally. Solutions or suspensions of these active compounds as a free base or pharmacologically acceptable salt can be prepared in water suitably mixed with a surfactant such as hydroxypropylcellulose. Dispersions can also be prepared in glycerol, liquid polyethYlene glycols and mixtures thereof in oils. Under ordinary conditions of storage and use, these preparations contain a preservative to prevent the growth of microorganisms.
The pharmaceutical forms suitable for injectable use include sterile aqueous solutions or dispersions and sterile powders for the extemporaneous preparation of sterile injectable solutions or dispersions. In all cases, the form must be sterile and must be fluid to the extent that easy syringability exists. It must be stable under the conditions of manufacture and storage and must be preserved against the contaminating action of microorganisms such as bacteria and fungi. The carrier can be a solvent or dispersion medium containing, for example, water, ethanol, polyol (e.g. glycerol, propylene glycol and liquid polyethylene glycol), suitable mixtures thereof, and vegetable oils.
The invention will be more fully described in conjunction with the following specific examples which are not to be construed as limiting the scope of the invention.
EXAMPLE 1
2,4,5-Trifluorobenzoio Acid
To a stirred suspension, under argon, of 9 g to magnesium chips in 150 ml of tetrahydrofuran containing a crystal of iodine and cooled to 0° C. was added a solution of 60 g of 2,4,5-trifluorophenyl bromide in 80 ml of tetrahydrofuran dropwise over 1.5 hours. The temperature was kept below 35° C. during the addition and kept at 35° C. for an additional hour then cooled to 0° C. A gentle stream of carbon dioxide was bubbled through the reaction mixture for one hour at 0° C., one hour at room temperature and one hour at reflux. The reaction mixture was cooled to 0° C. and poured into a beaker containing 300 ml of 2N hydrochloric acid and 200 ml of ice water. The aqueous mixture was filtered and the filtrate extracted with 3×335 ml of methylene chloride. The combined organic extracts were dried and the volatiles removed in vacuo to give 49.4 g of the desired compound. Crystallization from hexanes gave the desired product as light yellow crystals, mp 92°-95° C.
EXAMPLE 2
2,4,5-Trifluorobenzoyl chloride
To a solution of 5.24 g of 2,4,5-trifluorobenzoic acid in 50 ml of ether containing two drops of N,N-dimethylformamide was added, under argon, oxalyl chloride dropwise over 30 minutes. Stirring was continued for an additional 30 minutes when gas evolution ceased. The ether was removed in vacuo and the residue vacuum distilled to give 5.07 g of the desired compound, bp 26°-27° C./0.75 mm.
EXAMPLE 3
Ethyl 8,9-difluoro-6-oxo-6H-benzo[c]quinolizine-5-carboxylate
To a solution of 3.3 g of ethyl 2-pyridyl acetate in 50 ml of dry tetrahydrofuran at -5° C., under argon, was added 25 ml of lithium bis(trimethylsilyl)-amide in hexanes dropwise over 30 minutes. Stirring was continued for an additional 2 hours at -5° C. This mixture was added dropwise, under argon to a -5° C. solution of 3.9 g of 2,4,5 trifluorobenzoyl chloride in 50 ml of dry tetrahydrofuran over one hour. Following an additional hour of stirring the mixture was allowed to slowly reach room temperature. Water ice was added, the resulting solids collected, washed with cold water and dried giving 1.5 g of the desired compound, mp 200°-203° C.
EXAMPLE 4
Ethyl 7,8,9,10-tetrafluoro-6=oxo-6H=benzo[c]-quinolizine-5-carboxylate
A solution of 3.3 g of ethyl 2-pyridyl acetate in 50 ml of dry tetrahydrofuran was cooled to -5° C. and 25 ml of lithium bis(trimethylsilyl)amide in hexanes added dropwise over 30 minutes. Stirring was continued for an additional one hour at -5° C. This mixture was added dropwise under argon to a -5° C. solution of 4.6 g of pentafluorobenzoyl chloride in 50 ml of dry tetrahydrofuran over one hour. Following an additional 3 hours of stirring the mixture was allowed to slowly reach room temperature followed by stirring for 18 hours. The mixture was poured into ice water and extracted with dichloromethane. The separated organic layer was dried and the volatiles removed under vacuum to give a red semisolid which was stirred with acetone, the resulting solid collected, and dried giving 1.28 g of the desired product, mp 198°-200° C.
EXAMPLE 5
Ethyl 8-fluoro-9-(4-methyl-1-piperazinyl)-6-oxo-6H-benzo[c]quinolizine-5-carboxylate
A mixture of 2.0 g of ethyl 8,9-difluoro-6-oxo-6H-benzo[c]quinolizine-5-carboxylate and 3.3 g of N-methylpiperazine was heated at 110° C. for 2 hours. The solvent was evaporated and the residue partitioned between water and dichloromethane. The organic layer was dried and the solvent removed giving 2.0 g of the desired product, mp 167°-170° C.
EXAMPLE 6
8-Fluoro-9-(4-methyl-1-piperazinyl)-6-oxo-6H-benzo[c]quinolizine-5-carboxylic acid
A mixture of 0.38 g of ethyl 8-fluoro-9-(4-methyl-1-piperazinyl)-6-oxo-6H-benzo[c]quinolizine, 25 ml of 0.1N sodium hydroxide and 5 ml of ethyl alcohol was refluxed for 18 hours. The mixture was cooled to room temperature and the pH adjusted to 6 with acetic acid. Most of the volatiles were removed under vacuum to give 0.31 g of water washed and dried desired product, mp 264°-266° C.
EXAMPLE 7
Ethyl 8-fluoro-2,3,4,6-tetrahydro-9-(4-methyl-1-piperazinyl)-6-oxo-1H-benzo[c]quinolizine-5-carboxylate
A mixture of 0.35 g of ethyl 8-fluoro-9-(4-methyl-1-piperazinyl)-6-oxo-6H-benzo[c]quinolizine-5-carboxylate and 0.47 g of 10% palladium-on-carbon in 50 ml of trifluoroacetic acid was shaken under 40 lb. of hydrogen in a Parr apparatus for 18 hours. The mixture was filtered and the solvent evaporated. The concentrate was partitioned between aqueous potassium carbonate and dichloromethane. The organic layer was dried and the solvent removed giving 0.32 g of the desired compound, mp 163°-165° C.
EXAMPLE 8
Ethyl 8,9-difluoro-1,2,3,4-tetrahydro-6-oxo-6H-benzo[c]quinolizine-5-carboxylate
A mixture of 0.5 g of ethyl 8,9-difluoro-6-oxo-6H-benzo[c]quinolizine-5-carboxylate and 0.5 g of 10% palladium-on-carbon in 50 ml of trifluoroacetic acid was shaken under 40 lb. of hydrogen in a Parr apparatus for 2 hours. The mixture was filtered and the solvent evaporated. The concentrate was partitioned between aqueous sodium bicarbonate and dichloromethane. The organic layer was dried followed by adding hexanes to give 0.45 g of the desired product, mp 166°-168° C. | Novel substituted quinolinecarboxylic acid derivatives of the formula: ##STR1## wherein R 1 is hydrogen, alkali metal, alkaline earth metal or lower alkyl; R 2 is hydrogen, benzyl or alkyl (C 1 -C 3 ); X is hydrogen or fluoro; which have antibacterial activity, intermediates useful in the preparation of the compounds, methods of producing and using the compounds to treat bacterial infections in animals. | 2 |
RELATED APPLICATION
The present application claims the benefit of priority under 35 U.S.C. §119 (e) of Provisional application Ser. No. 60/007,075, filed Oct. 25, 1995.
BACKGROUND OF THE INVENTION
This invention relates to pulp refining apparatus and methods, and more particularly to an apparatus and method of employing generally low consistency pulp refining apparatus to produce pulp having properties comparable to pulp produced using high consistency refining techniques.
High consistency pulp refining is used to produce high strength paper such as is typically used in cement sacks and grocery bags. High consistency pulp however, is difficult to handle in that special pumping methods and other specially adapted equipment must be used to cause the pulp to flow through conduits of the refining system and to facilitate refining. The use of such specialized equipment requires a considerable investment in equipment which generally can only be used for one purpose--namely high consistency refining.
Low consistency pulp refining is much easier and less costly to do as conventional pump technology and relatively non-specialized equipment may be used to propel the pulp through conduits of the system and to effect refining. However, refined low consistency pulp does not have the same strength characteristics as high consistency pulp and therefore cannot be used in applications such as cement sacks and grocery bags.
Careful investigation of the process of refining has revealed that high consistency refining is achieved where there is a relatively high concentration of pulp fibres in a refining zone between oppositely facing refiner bars of either a conical or plate refiner. With high consistency pulp refining equipment, this high concentration of pulp is achieved due to the high concentration of pulp fibres in the pulp solution entering the refiner. As stated above, this requires specialized equipment.
What is desired therefore is a way of producing a low consistency refined pulp solution wherein the pulp has a strength comparable to that produced by high consistency refining methods, from a low consistency pulp solution. This is addressed by the present invention.
SUMMARY OF THE INVENTION
In accordance with one aspect of the invention, there is provided a refiner apparatus for exerting mechanical forces on pulp fibres. The apparatus includes a member having a pulp side and a drainage side, the pulp side having a plurality of spaced apart raised bar portions thereon. A plurality of drainage conduits are formed in the member, the conduits extending between the pulp side and the drainage side of the member, each drainage conduit having inlet and outlet openings respectively. The inlet openings are disposed on the pulp side of the member and the outlet openings are disposed on the drainage side of the member such that water expelled from pulp fibres forced against the pulp side is received in the inlet openings and is conducted through the drainage conduits to the drainage side of the member.
Preferably, each of the inlet openings has a diameter of approximately one-half of the average pulp fibre length of the pulp intended to be processed by the refiner apparatus and each of the inlet openings is spaced apart from an adjacent opening by a distance greater than the average pulp fibre length intended to be processed by the refiner apparatus.
Preferably, each of the drainage conduits has a length generally equal to the diameter of its corresponding inlet opening.
The member may include a generally disk-shaped plate operable to be rotated in a disk refiner, the drainage side being separated from the pulp side by the disk-shaped plate. Preferably, the disk-shaped plate has a drainage surface on the drainage side and a plurality of spacers for spacing the drainage surface from a mounting surface associated with the disk refiner such that water flowing from the outlet openings is operable to flow radially of the disk-shaped plate, between the drainage surface and the mounting surface for collection at an exhaust port of the disk refiner.
Preferably, the spacers include a plurality of generally radially extending wall portions projecting from and disposed on the drainage surface, the radially extending wall portions being operable to direct water to flow radially outwardly from the outlet openings when the disk-shaped plate is rotated.
The plate may have a plurality of collection conduits, each of the collection conduits being in communication with a plurality of outlet openings and being operable to channel water from respective outlet openings of the drainage conduits to the drainage side of the disk-shaped plate. Preferably, approximately seven outlet openings are in communication with one respective collection conduit.
In accordance with another aspect of the invention, there is provided an apparatus for refining pulp, the apparatus including first and second sets of facing refiner bars having opposing pulp sides, at least one of the sets being moveable relative to the other, and the first and second sets being positioned relative to each other such that mechanical pressure is applied to pulp fibres between opposing pulp sides of the refiner bars when the at least one of the sets is rotated. At least one of the sets of refiner bars has a drainage side separated from the pulp face side and has a plurality of drainage conduits for draining water from pulp fibres between the opposing face sides of the refiner bars.
Preferably, each of the drainage conduits has inlet and outlet openings respectively, the inlet openings being disposed on the pulp face sides of the bars of one of the sets and the outlet openings are disposed on the drainage sides of the bars such that water expelled from pulp fibres forced against the pulp side is received in the inlet openings and is conducted through the drainage conduits to the drainage side.
Preferably, each of the inlet openings has a diameter of approximately one-half of the average pulp fibre length of the pulp intended to be processed by the refiner apparatus and each of the inlet openings is spaced apart from an adjacent opening by a distance greater than the average pulp fibre length intended to be processed by the refiner apparatus.
Preferably, each of the drainage conduits has a length generally equal to the diameter of its corresponding inlet opening.
In accordance with another aspect of the invention, there is provided a method of refining pulp between facing refiner members of a pulp refiner in which at least one of the facing refiner members is movable relative to the other, the method including the step of draining water from pulp fibres squeezed between the facing refiner members, through at least one drainage conduit in at least one of the refiner members.
Preferably, the method includes the step of receiving water expelled from the pulp fibres squeezed between the facing refiner members, in a drainage opening disposed in a pulp side of the at least one of the refiner members the drainage opening being in communication with the at least one drainage conduit.
Also preferably, the method includes the step of conducting water received at the at least one drainage opening to a drainage area separated from the pulp side.
Further preferably, the method includes the step of dispersing water from the drainage area for collection at an exhaust port of the refiner.
Further preferably, the method includes the step of recombining refined pulp fibres with water collected at the exhaust port.
According to another aspect of the invention, there is provided a solution of refined pulp produced in accordance with the method above.
Effectively, the present invention drains water from the refining zone which creates a localized area of high consistency pulp solution therein. This allows low consistency pulp solution to be pumped into the refiner, allows the pulp to refined in a high consistency pulp solution and recombines the refined pulp so produced with the drained water to form a refined pulp in a low consistency solution which can be easily handled using conventional, non-specialized, low cost handling equipment. Thus, generally low-cost low consistency refining equipment and pulp handling technology can be used to produce a low consistency solution of refined pulp comparable in strength to that of high consistency refined pulp. Hence, pulp having increased strength can be economically produced.
BRIEF DESCRIPTION OF THE DRAWINGS
In drawings which illustrate embodiments of the invention,
FIG. 1 is a cross-sectional view of an apparatus according to a first embodiment of the invention;
FIG. 2 is a plan view of a pulp side of a disk-shaped refiner plate according to the first embodiment;
FIG. 3 is a fragmented, cross-sectional view of a bar portion and adjacent valley portions of the refiner plate shown in FIG. 2;
FIG. 4 is a bottom plan view of a drainage side of the refiner plate shown in FIG. 2; and
FIG. 5 is a schematic diagram illustrating a plurality of steps involved in a method of refining pulp, according to the invention.
DETAILED DESCRIPTION
Referring to FIG. 1, a pulp refining apparatus according to a first embodiment of the invention is shown generally at 10. Generally, the pulp refining apparatus shown is similar to conventional low consistency pulp refiners, with the exception of the refiner plates which are a key aspect of the present invention as described below.
Conventional, prior art components of the pulp refining apparatus shown in FIG. 1 include first and second housing portions 12 and 14. The first housing portion 12 includes an inlet conduit 16 for receiving pulp having a consistency of approximately 2% to 4%. The second housing portion 14 has a shaft 18 driven in rotation by a motor (not shown). The first and second housing portions are connected together in such a manner that a generally circular disk-shaped area 20 is defined between the first and second housing portions 12 and 14.
Within the circular disk shaped area, the inlet conduit 16 is terminated in a first stationary mounting plate 22 secured to the first housing portion 12. Also within this space, an end portion 24 of the shaft 18 is connected to a second mounting plate 26 which rotates with the shaft 18.
Non-conventional first and second disk-shaped refiner plates 28 and 30 according to the first embodiment of the invention, are connected to the conventional first and second mounting plates 22 and 26 such that the first refiner plate 28 is stationary and the second refiner 30 plate is rotated with the second mounting plate 26. Thus, the first and second refiner plates 28 and 30 are moveable relative to each other.
The first and second refiner plates 28 and 30 each have respective pulp sides 32 and 34 and drainage sides 36 and 38 disposed on opposite sides of each refiner plate 28 and 30, thus the pulp sides 32 and 34 and drainage sides 36 and 38 are separated from each other by the plates 22 and 26 themselves. The pulp sides 32 and 34 of respective plates face each other and define a refining zone 40 therebetween. The drainage sides 36 and 38 of each refiner plate 28 and 30 face their respective mounting plates 22 and 26. Generally, the pulp sides 32 and 34 are operable to receive pulp therebetween and the drainage sides facilitate dispersement of water.
Referring to FIG. 2, the first refiner plate is shown generally at 28 and has an annular disk-shape with a central relatively large circular opening 44 through which pulp may pass to enter the refining zone 40 shown in FIG. 1, when the apparatus is in use. The pulp side is shown generally at 32 and has a plurality of generally rectangular-parallelepiped shaped raised bar portions 46 formed therein. The bar portions 46 are spaced apart by respective rectangularly shaped valleys 48 having a width slightly larger than the width of the bar portions 46. In the embodiment shown, the width of the bar portions 46 is approximately 0.157 inches and the distance between centres of adjacent bar portions 46 is approximately 0.394 inches.
Generally, the entire pulp side 32 of the refiner plate 28 has a plurality of generally circular inlet openings 49 formed therein, with the exception of marginal portions 50 and 52 at the outer circumference of the plate 28 and surrounding the relatively large circular opening 44 respectively. The inlet openings 49 are located in the raised bar portions 46 and in the valleys 48 at an overall density of approximately 250-300 inlet openings per square inch. Referring to FIG. 3, the inlet openings 49 define associated respective drainage conduits 54 extending through the refiner plate 28, from the pulp side 32 to the drainage side 36, extending generally parallel to the axis 56 of the refiner plate 28 (the axis being shown in FIG. 2).
In this embodiment, the openings 49 and drainage conduits 54 each have a diameter of approximately 1mm. The diameter of the inlet openings 49 and drainage conduits 54 is desirably less than one-half of the average length of fibre intended to be refined by the apparatus as diameters greater than one-half the average length of the fibres tend to promote clogging of the openings 49 by the fibres. Diameters far less than one-half of the average fibre length will restrict the capacity to drain water from the fibres as will be described below. In this embodiment, the average length of fibres to be refined is approximately 2.4 mm. Generally, for most refining applications the average length of pulp fibre is between 1 mm and 4 mm and therefore the diameter of the inlet openings 49 may be between 0.5 and 2.0 mm.
Referring back to FIG. 2, to facilitate self-clearing of the drainage conduits 54, the drainage conduits 54 are arranged in clusters 57 of seven, including six drainage conduits 54 formed in a hexagonal shape about a central conduit. The distance between any two inlet openings of respective drainage conduits in each cluster is preferably no less than the average length of the fibres to be refined by the apparatus, to minimize bridging of fibres between adjacent inlet openings 49 and possible clogging of the openings.
Referring to FIGS. 3 and 4, to further facilitate self-clearing of the drainage conduits 54, a plurality of approximately 5 mm diameter collection conduits 58 are formed in the drainage side 36 of the refiner plate The drainage conduits are formed such that each cluster 57 of seven drainage conduits 54 terminates in a respective outlet opening 62, draining into an associated collection conduit 58. Hence, each collection conduit 58 is in communication with a plurality of outlet openings 62 and is operable to channel water from respective outlet openings 62 to the drainage side 36 of the refiner plate 28. The forming of the collection conduits 58 decreases the depths of the drainage conduits 54, to reduce clogging of the drainage conduits 54 by the pulp fibres, while still preserving the structural integrity of the refiner plate 28. In the embodiment shown, the collection conduits 58 are formed such that the depth of the drainage conduits having inlet openings 49 in the valleys 48 is approximately 1.5 mm. The bar portions 46, of course, will have drainage conduits 54 of greater depth, depending upon the amount by which they are raised from the valleys 48.
Referring to FIG. 4, the drainage side 36 has a drainage surface 64 in which is formed outlet openings 66 of respective collection conduits 58. Also formed in the drainage surface 64 is a generally annular wall portion 68 extending about the relatively large circular opening 44. From the annular wall portion there is a plurality of generally radially extending wall portions 70 extending therefrom, which act as a plurality of spacers for spacing the drainage surface 64 from a mounting surface 72 of the first mounting plate 22 shown in FIG. 1. Referring to FIG. 1, water flowing from the outlet openings 66 of the collection conduits 58 is operable to flow radially of the refiner plate 28, between the drainage surface 64 and the mounting surface 72. Referring back to FIG. 4, the radially extending wall portions 70 each have respective mounting openings 74 through which conventional fasteners (not shown) are inserted to secure the refiner plate 28 to the mounting plate 22, shown in FIG. 1.
Generally, the second refiner plate 30 is similar to the first plate 28 with the exception that the second plate has no central relatively large opening, but rather has a true disk shape. It does however, have bar portions, valleys and drainage conduits etc. like the first refiner plate 28.
Operation
Referring to FIG. 1, a conventional solution of low consistency pulp solution 76 is pumped through the inlet conduit 16 and into the refining zone 40, using conventional, low cost pump technology (not shown).
Referring to FIG. 5, sub-figures a-e depict activity occurring in the refining zone 40 shown in FIG. 1. Each sub-figure shows left-hand and right-hand bar portions 78 and 80, the left-hand bar portions 78 being associated with the first refiner plate 28 and the right-hand bar portions 80 being associated with the second refiner plate 30. In each sub-figure case the left-hand bar portions 78 are stationary while the right-hand bar portions 78 are moving upwardly, in the direction indicated by the arrow 82.
Referring to FIG. 5a, pulp fibres 84 are gathered in wads 85 on a leading edge 88 of the moving bar portion 80 as it moves in the refining zone 40. As the pulp fibres 84 are gathered by the leading edge 88, impact of the bar portion 80 with the pulp fibres 84 causes preliminary, localized dewatering of the pulp fibres 84. At least some of this water drains through inlet openings 49 in the valleys 48 between the bar portions 78 and 80.
Referring to FIG. 5b, as the right-hand bar portions 78 approach the left-hand bar portions 78, mechanical pressure is exerted on the pulp fibres 84 causing them to further expel water, which drains into the inlet openings 49 in the valleys 48 and in the bar portions 78 and 80.
Referring to FIG. 5c, as the bar portions pass each other, the pulp fibres 84 are fully compressed and any water in the area between adjacent faces of the bar portions is forced through the inlet openings 49. Hence, water is drained from pulp fibres 84 squeezed between facing refiner bar portions, through at least one drainage conduit 54 in at least one of the refiner bar portions 78 and 80. The pulp fibres 84 slide under pressure between opposing faces of the bar portions 78 and 80 however, the fibres generally do not enter the inlet openings 49 as they are generally longer than the diameter of the inlet openings 49 and are oriented diametrically across the inlet openings 49.
Referring to FIG. 5d, as the right-hand bar portion 80 moves past the left-hand bar portion 78, the mechanical pressure on the pulp fibres 84 is released.
FIG. 5e illustrates dispersion of the refined pulp fibres 84 after the right-hand bar portion has past the left hand bar portion 78.
Referring back to FIG. 1, generally, the drainage of water from the refining zone 40 via the drainage conduits 54 reduces the ratio of water to pulp fibre 84 in that area, effectively increasing the consistency of the pulp solution in the refining zone 40. Hence, the pulp solution is of localized high consistency in the refining zone 40 and the benefits of high consistency refining are realized. Such benefits include good beating response due to increased fibre-to-fibre contact and less cutting action.
Water flowing into the inlet openings 49 during the above process drains through the drainage conduits 54 in the bar portions 78 and 80 and in the valleys 48, into respective collection conduits 58 and to the drainage sides 36 and 38 of the plates 28 and 30, between the drainage surfaces 64 and the associated mounting surfaces 72 and 73. With the first refiner plate 28, which is stationary, the water simply drains radially downwardly by gravity into an exhaust port 86 of the apparatus. With the second refiner plate 30, water from the collection conduits 58 flows radially outwardly, between the drainage surface 64 and the mounting surface 73 and strikes the annular housing 89 where it runs downwardly under the influence of gravity and collects at the exhaust port 86 of the apparatus. Eventually, the refined fibres 90 also reach the exhaust port 86 where they recombine with water 92 expelled earlier in the process, generally re-forming a low consistency solution of pulp 94 which is easy to handle using conventional, low cost pumping equipment methods.
In general, low consistency pulp solution is fed into the apparatus and low consistency, refined pulp solution is produced by the apparatus, however, inside the apparatus, in the refining zone 40, water is drained from the pulp solution making it a locally high consistency solution and therefore, the pulp is refined as a high consistency solution and enjoys the attendant benefits of high consistency refining. Since the pulp fed into the apparatus and the refined pulp produced by the apparatus is of low consistency, conventional low consistency pulp handing technology may be employed outside of the apparatus. This reduces the cost of producing high consistency refined pulp. By employing the present invention low consistency equipment may be used with the plates described in connection with FIGS. 1-4 to achieve generally the same results as attainable with high consistency refining equipment.
While specific embodiments of the invention have been described and illustrated, such embodiments should be considered illustrative of the invention only and not as limiting the invention as construed in accordance with the accompanying claims. | A refiner-apparatus and method for producing refined pulp by exerting mechanical forces on pulp fibres. The apparatus includes a member having a pulp side and a drainage side, the pulp side having a plurality of spaced apart raised bar portions thereon. A plurality of drainage conduits are formed in the member, the conduits extending between the pulp side and the drainage side of the member, each drainage conduit having inlet and outlet openings respectively. The inlet openings are disposed on the pulp side of the member and the outlet openings are disposed on the drainage side of the member such that water expelled from pulp fibres forced against the pulp side is received in the inlet openings and is conducted through the drainage conduits to the drainage side of the member. Generally, the method involves draining water from pulp fibres squeezed between facing refiner members, through at least one drainage conduit in at least one of the refiner members. Use of the method produces a low consistency pulp solution of refined pulp having properties comparable to high consistency refined pulp. | 3 |
[0001] This application is a continuation of U.S. patent application Ser. No. 09/422,131 which was filed on Oct. 20, 1999.
TECHNICAL FIELD
[0002] This invention relates to an ordering method and apparatus for broadcast radio programs used by a person in motion.
BACKGROUND ART
[0003] Many people spend significant amounts of time traveling on a regular basis. Commuters using automobiles and mass transport fill the streets and transportation depots of many metropolitan areas several times a day for many hours. Others using bicycles and other wheeled vehicles are seen not only at rush hours, but also at other times throughout the week and on holidays. Still others prefer to long distance running and walking. All of these people have the opportunity to purchase radio receivers which enable them to enjoy broadcast radio programs of a wide variety, including entertainment such as music, dramatic productions, comedies, interviews, story telling sessions, as well as news and other factual radio programs including investment shows as well as advertisements and/or commercials.
[0004] [0004]FIG. 1 depicts typical prior art vehicular radio receivers and cellular telephones. The basic receiver 10 of today often possesses an indicator 2 visually presenting some status information, such as whether the FM receiver is active, and if so, its tuner frequency. There is often a door 4 permitting loading and unloading of audio recording media, such as cassette tapes or CD's. Other alternatives include downloaded audio files on nonvolatile memory components. There is usually an array of push buttons 6 , which may be arranged in a variety of configurations, which may or may not form a regular pattern. Sometimes there are dials 8 . This basic receiver 10 is usually able to receive both AM and FM broadcasts as well as often play recorded material such as cassette tapes or CDs. Audio output is often achieved in automobiles using speakers 12 and 14 coupled to the receiver 10 by wires 16 and 18 , respectively.
[0005] Other kinds of commuters and travelers usually cannot afford the space of separately detached speakers. Another solution includes a headset 20 including left and right speakers 22 and 24 sometimes with all the electronics for broadcast radio reception being resident in the headset 20 , sometimes with an antenna 30 . Volume and tuning controls 26 are often mounted on the earphone-speaker sections such as 22 . Batteries 28 are often mounted in the headset 20 as shown. A further progression includes an addition of microphone 34 attached by a mount 32 to the headset. Still further refinements include cabling 40 to a unit 42 , which is often mounted on a belt.
[0006] This belt-mounted unit 42 often contains the active electronic components of the basic receiver 10 discussed above. Belt-mounted unit 42 often further contains an indicator 44 visually presenting some status information, a door 46 permitting loading and unloading of audio recording media and an array of push buttons 48 . Such units 42 usually receive both AM and FM broadcasts as well as often play recorded material such as cassette tapes or CDs. Some performing artists use versions of devices resembling these units 20 - 40 - 42 in place of hand held microphones and headsets. In such circumstances, the units act as transceivers, similar to cellular telephones, although with higher fidelity than standard cellular telephones. Additionally, cellular telephones 50 possessing a microphone 52 and earphone 54 , a push button array 56 and sometimes an antenna 58 have become common throughout much of the world.
[0007] [0007]FIG. 2 depicts a simplified block diagram of a typical, prior art broadcast radio receiver. FM antenna 100 is coupled 102 to FM Tuner 104 . FM Tuner 104 is coupled 106 to FM Intermediate Frequency Processor (IF) 110 , from which the stereo audio signals 110 are presented to Analog Multiplexer/Switch 150 . AM antenna 120 is coupled 122 to AM Tuner 124 . AM Tuner 124 presents the audio signal 126 to Analog Multiplexer/Switch 150 . Tape drive 140 is coupled 142 to Tape Preamp 144 . Tape Preamp 144 presents the stereo audio signals 146 to Analog Multiplexer/Switch 150 .
[0008] Analog Multiplexer/Switch 150 is usually manually controlled to select from a collection of inputs such as discussed above. It generates one or more audio signals 162 which are presented to Tone and Volume Control 160 , which generates audio signals 166 which are presented to one or more power amplifiers 164 . Power amplifiers 164 generate one or more audio signals presented 170 to Audio Speaker System 168 . The Audio Speaker System 168 involves one or more speakers, which may reside in a headset, rigidly mounted on the sides of an enclosure such as a boom box, or distributed some distance from each other, as in an automobile. Often the mechanism of presentation 170 to the audio speaker system is through a wire-based physical transport layer, but in certain situations, it may be through a wireless physical transport layer. These systems have been a staple of the consumer electronics market for a quarter of a century, remaining virtually unchanged in that time. However, there are some frustrations associated with such systems and the above mentioned cellular telephones.
[0009] There is a subsidiary FM signal protocol known as RDS in the United States (and often referred to as RDBS in Europe), which has been adopted and deployed in a number of radio markets within the United States. RDS specifies a sub-band within the channel bandwidth of a standard FM broadcast station, which does not interfere with the audio sub-band of the FM transmission. The sub-band is currently used to broadcast digital information such as standard identification information of the standard broadcast station. From certain perspectives, this sub-band can be viewed as a sub-carrier used for additional analog and/or digital information.
[0010] [0010]FIG. 3 depicts an exemplary prior art mobile computer 200 capable of being installed in an automobile. Computer 200 typically is designed to mount on or near the dashboard of an automobile, but could conceptually be mounted on the handle bars of a bicycle. Assembly 202 - 204 - 206 acts as a selection device similar in some ways to a mouse or joy stick. Push plate 204 , when depressed away from its center, selects a region such as 206 . Region 202 in certain situations contains a number of designations useful in selecting specific common options. Display 210 portrays the state of the computer, providing the main user output. Buttons 212 , 214 and 216 provide a further array of user tactile inputs.
[0011] Systems such as this have recently come onto the market here in the United States. Many of these systems run handheld computer operating systems and often feature menu driven control systems further accessing one or more nonvolatile memory systems, such as CDs, disk drives or nonvolatile semiconductor memories. However, even with such new systems, there are some frustrations associated with this kind of device and the above mentioned radio receivers and cellular telephones. Consider the situation where there is an interest in buying a copy of the radio program either being heard or having just been heard. How is this to be done? Today one faces an inherently frustrating situation. One approach is to somehow note what was played. One might call some distributor on the telephone to order the radio program. This is often at least distracting, if not dangerous, for motorists, whose life and health, as well as the lives and health of those around them, depends upon them staying focused on driving. For other most people in motion, simultaneously dealing with a cellular telephone and a broadcast radio receiver would be quite inconvenient, if not again distracting and potentially dangerous.
[0012] One might wait to visit a store selling such merchandise. This requires that somehow one remember what was played and who performed it at the least. In almost all the situations described above, this is again inconvenient, distracting and potentially dangerous.
[0013] An alternative would be to note the radio program, channel and broadcast time and use this information to order the radio program. Such a system has been recently granted a patent (U.S. Pat. No. 5,539,635). Characteristic of such systems is the following description of the user's actions to order a radio program taken from the Summary of the Invention (column 2, lines 18-21 ). “A customer uses her telephone to call into the system and gives the date, time, and broadcaster of when she heard each requested program broadcasted.” This would again be inconvenient, distracting and in many circumstances for people in motion, dangerous.
[0014] An additional problem confronts the user in motion: financial information disclosure. Cellular telephones can often be overheard electronically. In mass transports, people in the vicinity of a user may well overhear critical identifying information such as credit card or subscriber numbers. Similar situations often occur for individuals on bicycles and on foot.
[0015] What is needed is a method of ordering radio programs which is convenient, extremely easy to perform while in motion and simultaneously capable of being secure. What is also needed is a class of radio devices supporting such methods of ordering. What is also needed is a method of controlling such radio devices so users may order radio programs in the manners discussed hereinafter.
DISCLOSURE OF THE INVENTION
[0016] The present invention answers all of these needs. The method of use presents an extremely efficient manner of ordering a radio program occurring at approximately the time presented, minimizing the need to remember any details. The method is embodied in a range of tactile and voice controls which people in motion need to have. Security options include voice signatures, button sequences and fingerprint identification. User feedback is embodied in both audio and visual display formats.
[0017] The radio device supports an IF signal source containing essential information on the radio program, an embedded controller, user interface as well as a radio transceiver by which the ordering transaction is carried out. The IF signal source may be digital or analog. The embedded controller contains a writeable nonvolatile memory supporting the control program and security signatures. The user interface supports push buttons, audio input and output to the user, as well as visual output to the user and a fingerprint scanner. The radio transceiver may be embodied as a cellular telephone or bi-directional pager.
[0018] The method of controlling the radio supports the basic actions of placing an order, querying the ordering system for additional information, initializing a user's identifying signature, initializing a session by identifying a user, blocking access to ordering if the user is not identified, and in certain embodiments, calling the police. In certain embodiments, the user's identifying signature may include one or more of button sequences, voice signature and fingerprint. These and other advantages of the present invention will become apparent upon reading the following detailed descriptions and studying the various figures of the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] [0019]FIG. 1 depicts typical prior art vehicular radio receivers;
[0020] [0020]FIG. 2 depicts a simplified block diagram of a typical, prior art broadcast radio receiver;
[0021] [0021]FIG. 3 depicts an exemplary prior art mobile computer capable of being installed in an automobile;
[0022] [0022]FIG. 4 depicts a flowchart of using a vehicular radio-based program selection and ordering system in accordance with an embodiment;
[0023] [0023]FIG. 5 depicts a detail flowchart of operation 1008 of FIG. 4, which selects the radio program near the time of the radio program presentation in accordance with certain embodiments;
[0024] [0024]FIG. 6 depicts a detail flowchart of operation 1008 of FIG. 4, which selects the radio program near the time of the radio program presentation in accordance with certain embodiments;
[0025] [0025]FIG. 7 depicts a detail flowchart of operation 1012 of FIG. 4, which perceives the radio program selection confirmation in accordance with certain embodiments;
[0026] [0026]FIG. 8 depicts a detail flowchart of operation 1012 of FIG. 4, which perceives the radio program selection confirmation in accordance with certain embodiments;
[0027] [0027]FIG. 9 depicts a flowchart of additional operation 1120 of identifying a vehicle owner to operation 1000 of FIG. 4 in accordance to certain embodiments;
[0028] [0028]FIG. 10 depicts a detail flowchart of operation 1016 of FIG. 4 responding to radio program selection confirmation in accordance to certain embodiments;
[0029] [0029]FIG. 11 depicts a detail flowchart of operation 1124 of FIG. 9 identifying said vehicle owner in accordance to certain embodiments;
[0030] [0030]FIG. 12 depicts a flowchart of additional operation 1190 of initializing the owner identifying signature sequence to operation 1120 of FIG. 9 in accordance to certain embodiments;
[0031] [0031]FIG. 13 depicts a detail flowchart of operation 1124 of FIG. 9 identifying said vehicle owner in accordance to certain embodiments;
[0032] [0032]FIG. 14 depicts a flowchart of additional operation 1190 of initializing the owner identifying button sequence to operation 1120 of FIG. 9 in accordance to certain embodiments;
[0033] [0033]FIG. 15 depicts a detail flowchart of operation 1124 of FIG. 9 identifying said vehicle owner in accordance to certain embodiments;
[0034] [0034]FIG. 16 depicts a flowchart of additional operation 1270 of initially pressing the fingerprint scanner to operation 1120 of FIG. 9 in accordance to certain embodiments;
[0035] [0035]FIG. 17 depicts a detail flowchart of operation 1142 of ordering the radio program selection FIG. 10 in accordance to certain embodiments;
[0036] [0036]FIG. 18 depicts a flowchart controlling a vehicular radio-based program selection and ordering system;
[0037] [0037]FIG. 19 depicts a detail flowchart of operation 1404 of FIG. 18 receiving a coded radio program data channel in accordance to certain embodiments;
[0038] [0038]FIG. 20 depicts a detail flowchart of operation 1412 of FIG. 18 sensing the radio program in accordance to certain embodiments;
[0039] [0039]FIG. 21 depicts a detail flowchart of operation 1416 of FIG. 18 displaying the radio program confirmation in accordance to certain embodiments;
[0040] [0040]FIG. 22 depicts a detail flowchart of operation 1420 of FIG. 18 sensing the response to the displayed radio program confirmation in accordance to certain embodiments;
[0041] [0041]FIG. 23 depicts a detail flowchart of operation 1532 of FIG. 22 ordering the radio program in accordance to certain embodiments;
[0042] [0042]FIG. 24 depicts another flowchart of operations controlling a vehicular radio-based program selection and ordering system in accordance with certain embodiments;
[0043] [0043]FIG. 25 depicts a detail flowchart of operation 1412 of FIG. 18 determining selection of the sensed radio program in accordance to certain embodiments;
[0044] [0044]FIG. 26 depicts a detail flowchart of operation 1562 of FIG. 22 determining to order the selected radio program in accordance to certain embodiments;
[0045] [0045]FIG. 27 depicts a detail flowchart of operation 1416 of FIG. 18 displaying the radio program confirmation text in accordance to certain embodiments;
[0046] [0046]FIG. 28 depicts a detail flowchart of operation 1416 of FIG. 18 displaying the radio program confirmation text in accordance to certain embodiments;
[0047] [0047]FIG. 29 depicts a detail flowchart of operation 1416 of FIG. 18 displaying the radio program confirmation text in accordance to certain embodiments;
[0048] [0048]FIG. 30 depicts another flowchart of operations controlling a vehicular radio-based program selection and ordering system in accordance with certain embodiments;
[0049] [0049]FIG. 31 depicts a detail flowchart of operation 1762 of FIG. 30 initializing a usage session for a first user utilizing the signature for the specific user in accordance to certain embodiments;
[0050] [0050]FIG. 32 depicts a detail flowchart of operation 1790 of FIG. 31 blocking access by the first user whenever the comparison is non-matching in accordance to certain embodiments;
[0051] [0051]FIG. 33 depicts a high level system block diagram showing a computer with several forms of memory which in different embodiments provide residence for programs implementing the disclosed and claimed methods of controlling a vehicular radio;
[0052] [0052]FIG. 34 depicts a summary flowchart of using a vehicular radio-based program selection and ordering system in accordance with an embodiment;
[0053] [0053]FIG. 35 depicts a summary flowchart of operations controlling a vehicular radio-based program selection and ordering system in accordance with certain embodiments;
[0054] [0054]FIG. 36 depicts a system block diagram of a radio for receiving a radio program data channel, and conducting transactions in accordance with certain embodiments;
[0055] [0055]FIG. 37 depicts a detail system block diagram system block 2002 , a receiver of the radio program data channel as shown in FIG. 36 in accordance with certain further embodiments;
[0056] [0056]FIG. 38 depicts a detail system block diagram of radio program data channel isolator 2030 as shown in FIG. 37 in accordance with certain further embodiments wherein the external IF signal input port supports an analog signal protocol;
[0057] [0057]FIG. 39 depicts a detail system block diagram of analog isolation circuit 2050 as shown in FIG. 38 in accordance with certain further embodiments wherein the external IF signal input port supports an analog signal protocol;
[0058] [0058]FIG. 40 depicts a detail system block diagram of user interface 2020 as shown in FIG. 36 in accordance with certain embodiments supporting a user interface audio output interface providing audio output of the user output data;
[0059] [0059]FIG. 41 depicts a detail system block diagram of user interface 2020 as shown in FIG. 36 in accordance with certain embodiments supporting a user interface audio input sensor providing an user audio input data stream;
[0060] [0060]FIG. 42 depicts a detail system block diagram of user interface 2020 as shown in FIG. 36 in accordance with certain embodiments supporting a visual output device providing visual output of the user output data;
[0061] [0061]FIG. 43 depicts a detail system block diagram of user interface 2020 as shown in FIG. 36 in accordance with certain embodiments supporting a user interface tactile input sensor providing an user tactile input data stream;
[0062] [0062]FIG. 44 depicts a detail system block diagram of user interface tactile input sensor 2140 as shown in FIG. 43 in accordance with certain embodiments supporting a user interface tactile input sensor including a button sensor;
[0063] [0063]FIG. 45 depicts a detail system block diagram of user interface tactile input sensor 2140 as shown in FIG. 43 in accordance with certain embodiments supporting a user interface tactile input sensor including a fingerprint scanner;
[0064] [0064]FIG. 46 depicts a detail system block diagram of radio transceiver 2010 as shown in FIG. 36 in accordance with certain embodiments supporting the radio transceiver including a cellular telephone; and
[0065] [0065]FIG. 47 depicts a detail system block diagram of radio transceiver 2010 as shown in FIG. 36 in accordance with certain embodiments supporting the radio transceiver including a bi-directional pager.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0066] [0066]FIGS. 1, 2 and 3 refer to prior art and were previously discussed in the Background of the Invention.
[0067] Discussion of Primary Terms as used herein:
[0068] Radio-based programs refer to recognizable programming entities available upon a wireless broadcast physical transport. Radio-based programs include but are not limited to presentations of entertainment, education, news and commentary. Such presentations include but are not limited to copyrighted music, dramatic productions, storytelling, comedies, interviews and news stories. Such presentations also include but are not limited to stock market analyses and reports as well as advertisements and commercials.
[0069] Vehicular radio refers to radio systems supporting reception of broadcast radio-based programs in venues where the listener is either in motion, such as a bicycle, running, roller blading, skateboarding, or driving an automobile, truck, van or motorcycle.
[0070] Vehicle button array refers to one or more buttons which the vehicular radio user may touch or press and which affects the operation of the vehicular radio.
[0071] Embedded controller refers to a digital control system, including but not limited to, a computer coupled to a computer readable memory. Readable memory may include more than one kind of computer memory, such as CD ROMs, disk drives, RAM, nonvolatile semiconductor memory and removable storage devices coupled to the embedded controller by a removable storage interface. Removable storage devices include but are not limited to floppy disks, CD's, and semiconductor disks. Writeable non-volatile memory refers to non-volatile memory including at least one accessible word which may be purposefully altered. Non-volatility memory will retain its contents when power is no longer supplied to the memory.
[0072] [0072]FIG. 4 depicts a flowchart of using a vehicular radio-based program selection and ordering system in accordance with an embodiment of the present invention. Operation 1000 starts the operations of this flowchart. Arrow 1002 directs the use from operation 1000 to operation 1004 . Operation 1004 performs perceiving a radio program presentation. Arrow 1006 directs the usage from operation 1004 to operation 1008 . Operation 1008 performs selecting the radio program near the time of the radio program presentation. Arrow 1010 directs the usage from operation 1008 to operation 1012 . Operation 1012 performs perceiving the radio program selection confirmation. Arrow 1014 directs the usage from operation 1012 to operation 1016 . Operation 1016 performs responding to the radio program selection confirmation. Arrow 1018 directs the usage from operation 1016 to operation 1020 . Operation 1020 terminates the operations of this flowchart.
[0073] [0073]FIG. 5 depicts a detail flowchart of operation 1008 of FIG. 4, which selects the radio program near the time of the radio program presentation in accordance with certain embodiments. Arrow 1040 directs the use from starting operation 1008 to operation 1042 . Operation 1042 performs acoustic signaling selecting of said radio program. Arrow 1044 directs the usage from operation 1042 to operation 1046 . Operation 1046 terminates the operations of this flowchart.
[0074] [0074]FIG. 6 depicts a detail flowchart of operation 1008 of FIG. 4, which selects the radio program near the time of the radio program presentation in accordance with certain embodiments. Arrow 1060 directs the use from starting operation 1008 to operation 1062 . Operation 1062 performs pushing at least one button to signal selecting of said radio program. Arrow 1064 directs the usage from operation 1062 to operation 1066 . Operation 1066 terminates the operations of this flowchart.
[0075] [0075]FIG. 7 depicts a detail flowchart of operation 1012 of FIG. 4, which perceives the radio program selection confirmation in accordance with certain embodiments. Arrow 1080 directs the use from starting operation 1010 to operation 1082 . Operation 1082 performs hearing a radio program selection description. Arrow 1084 directs the usage from operation 1082 to operation 1086 . Operation 1086 terminates the operations of this flowchart.
[0076] [0076]FIG. 8 depicts a detail flowchart of operation 1012 of FIG. 4, which perceives the radio program selection confirmation in accordance with certain embodiments. Arrow 1100 directs the use from starting operation 1010 to operation 1102 . Operation 1102 performs reading a radio program selection description. Arrow 1104 directs the usage from operation 1102 to operation 1106 . Operation 1106 terminates the operations of this flowchart.
[0077] [0077]FIG. 9 depicts a flowchart of additional operation 1120 of identifying a vehicle owner to operation 1000 of FIG. 4 in accordance to certain embodiments. Operation 1120 starts the operations of this flowchart. Arrow 1122 directs the use from operation 1120 to operation 1124 . Operation 1124 performs identifying a vehicle owner. Arrow 1126 directs the usage from operation 1124 to operation 1128 . Operation 1128 terminates the operations of this flowchart.
[0078] [0078]FIG. 10 depicts a detail flowchart of operation 1016 of responding to the radio program selection confirmation in accordance to certain embodiments. Arrow 1140 directs the use from starting operation 1016 to operation 1142 . Operation 1142 performs ordering the radio program selection. Arrow 1144 directs the usage from operation 1142 to operation 1146 . Operation 1146 terminates the operations of this flowchart. Arrow 1150 directs the use from starting operation 1016 to operation 1152 . Operation 1152 performs canceling the radio program selection. Arrow 1154 directs the usage from operation 1152 to operation 1146 . Operation 1146 terminates the operations of this flowchart.
[0079] Note that usage may either perform ordering the radio program selection or canceling the radio program selection. Cancellation may be automatic in certain embodiments after a certain predetermined time interval has elapsed.
[0080] [0080]FIG. 11 depicts a detail flowchart of operation 1124 of FIG. 9 identifying said vehicle owner in accordance to certain embodiments. Arrow 1170 directs the use from starting operation 1124 to operation 1172 . Operation 1172 performs speaking an owner identifying signature sequence. Arrow 1174 directs the usage from operation 1172 to operation 1176 . Operation 1176 terminates the operations of this flowchart.
[0081] Note that in certain embodiments, operation 1172 may be performed only once during a radio program session. In certain further embodiments, such a radio program session may be terminated if there is no user response within a predetermined time interval.
[0082] [0082]FIG. 12 depicts a flowchart of additional operation 1190 of initializing the owner identifying signature sequence to operation 1120 of FIG. 9 in accordance to certain embodiments. Operation 1190 starts the operations of this flowchart. Arrow 1192 directs the use from operation 1190 to operation 1194 . Operation 1194 performs initializing the owner identifying signature sequence. Arrow 1196 directs the usage from operation 1194 to operation 1198 . Operation 1198 terminates the operations of this flowchart.
[0083] Note that in certain embodiments, operation 1190 may be performed once upon purchasing the device being used. In certain further embodiments, more than one owner identifying signature sequence may be initialized. In certain alternative embodiments, operation 1190 may be performed after purchasing the device being used.
[0084] [0084]FIG. 13 depicts a detail flowchart of operation 1124 of FIG. 9 identifying said vehicle owner in accordance to certain embodiments. Arrow 1210 directs the use from starting operation 1124 to operation 1212 . Operation 1212 performs pushing an owner identifying button sequence. Arrow 1214 directs the usage from operation 1212 to operation 1216 . Operation 1216 terminates the operations of this flowchart. Note that in certain embodiments, operation 1212 may be performed only once during a radio program session. In certain further embodiments, such a radio program session may be terminated if there is no user response within a predetermined time interval.
[0085] [0085]FIG. 14 depicts a flowchart of additional operation 1190 of initializing the owner identifying button sequence to operation 1120 of FIG. 9 in accordance to certain embodiments. Operation 1230 starts the operations of this flowchart. Arrow 1232 directs the use from operation 1230 to operation 1234 . Operation 1234 performs initializing the owner identifying button sequence. Arrow 1236 directs the usage from operation 1234 to operation 1238 . Operation 1238 terminates the operations of this flowchart.
[0086] Note that in certain embodiments, operation 1230 may be performed once upon purchasing the device being used. In certain further embodiments, more than one owner identifying button sequence may be initialized. In certain alternative embodiments, operation 1230 may be performed after purchasing the device being used.
[0087] [0087]FIG. 15 depicts a detail flowchart of operation 1124 of FIG. 9 identifying said vehicle owner in accordance to certain embodiments. Arrow 1250 directs the use from starting operation 1124 to operation 1252 . Operation 1252 performs pressing a fingerprint scanner. Arrow 1254 directs the usage from operation 1252 to operation 1256 . Operation 1256 terminates the operations of this flowchart.
[0088] Note that in certain embodiments, operation 1252 may be performed only once during a radio program session. In certain further embodiments, such a radio program session may be terminated if there is no user response within a predetermined time interval.
[0089] [0089]FIG. 16 depicts a flowchart of additional operation 1270 of initially pressing the fingerprint scanner to operation 1120 of FIG. 9 in accordance to certain embodiments. Operation 1270 starts the operations of this flowchart. Arrow 1272 directs the use from operation 1270 to operation 1274 . Operation 1274 performs initially pressing the fingerprint scanner. Arrow 1276 directs the usage from operation 1274 to operation 1278 . Operation 1278 terminates the operations of this flowchart.
[0090] Note that in certain embodiments, operation 1274 may be performed once upon purchasing the device being used. In certain further embodiments, more than one owner fingerprint scan may be initialized. In certain alternative embodiments, operation 1274 may be performed after purchasing the device being used.
[0091] [0091]FIG. 17 depicts a detail flowchart of operation 1142 of ordering the radio program selection FIG. 10 in accordance to certain embodiments. Arrow 1290 directs the use from starting operation 1142 to operation 1292 . Operation 1292 performs pressing the fingerprint scanner. Arrow 1294 directs the usage from operation 1292 to operation 1296 . Operation 1296 terminates the operations of this flowchart.
[0092] [0092]FIG. 18 depicts a flowchart controlling a vehicular radio-based program selection and ordering system. Operation 1400 starts the operations of this flowchart. Arrow 1402 directs the flow of execution from operation 1400 to operation 1404 . Operation 1404 performs receiving a coded radio program data channel. Arrow 1406 directs execution from operation 1404 to operation 1408 . Operation 1408 performs sensing a radio program. Arrow 1410 directs execution from operation 1408 to operation 1412 . Operation 1412 performs determining selection of said sensed radio program. Arrow 1414 directs execution from operation 1412 to operation 1416 . Operation 1416 performs displaying the radio program confirmation from the received coded radio program data channel whenever the radio program is sensed. Arrow 1418 directs execution from operation 1416 to operation 1420 . Operation 1420 performs sensing a response to the displayed radio program confirmation and said selection of said sensed radio program. Arrow 1422 directs execution from operation 1420 to operation 1424 . Operation 1424 terminates the operations of this flowchart.
[0093] [0093]FIG. 19 depicts a detail flowchart of operation 1404 of FIG. 18 receiving a coded radio program data channel in accordance to certain embodiments. Arrow 1440 directs the flow of execution from starting operation 1404 to operation 1442 . Operation 1442 performs sensing an internal radio program data channel. Arrow 1444 directs execution from operation 1442 to operation 1446 . Operation 1446 performs processing the sensed internal radio program data channel to create a radio program data descriptor stream. Arrow 1448 directs execution from operation 1446 to operation 1450 . Operation 1450 terminates the operations of this flowchart.
[0094] [0094]FIG. 20 depicts a detail flowchart of operation 1412 of FIG. 18 sensing the radio program in accordance to certain embodiments. Arrow 1470 directs the flow of execution from starting operation 1412 to operation 1472 . Operation 1472 performs sensing a radio program channel number to create a sensed radio channel number. Arrow 1474 directs execution from operation 1472 to operation 1476 . Operation 1476 performs decoding the radio program data descriptor stream based upon the sensed radio channel number to create a radio program data descriptor for the sensed radio program. Arrow 1478 directs execution from operation 1476 to operation 1480 . Operation 1480 terminates the operations of this flowchart. FIG. 21 depicts a detail flowchart of operation 1416 of FIG. 18 displaying the radio program confirmation in accordance to certain embodiments. Arrow 1500 directs the flow of execution from starting operation 1416 to operation 1502 . Operation 1502 performs generating a radio program confirmation text. Arrow 1504 directs execution from operation 1502 to operation 1506 . Operation 1506 performs displaying the radio program confirmation text. Arrow 1508 directs execution from operation 1506 to operation 1510 . Operation 1510 terminates the operations of this flowchart.
[0095] [0095]FIG. 22 depicts a detail flowchart of operation 1420 of FIG. 18 sensing the response to the displayed radio program confirmation in accordance to certain embodiments. Arrow 1530 directs the flow of execution from starting operation 1420 to operation 1532 . Operation 1532 performs ordering the selected radio program. Arrow 1534 directs execution from operation 1532 to operation 1536 . Operation 1536 terminates the operations of this flowchart.
[0096] Arrow 1540 directs the flow of execution from starting operation 1420 to operation 1542 . Operation 1542 performs determining to cancel the selected radio program. Arrow 1544 directs execution from operation 1542 to operation 1536 . Operation 1536 terminates the operations of this flowchart.
[0097] [0097]FIG. 23 depicts a detail flowchart of operation 1532 of FIG. 22 ordering the radio program in accordance to certain embodiments. Arrow 1560 directs the flow of execution from starting operation 1532 to operation 1562 . Operation 1562 performs determining to order the selected radio program. Arrow 1564 directs execution from operation 1562 to operation 1566 , whenever operation 1562 is asserted (Yes). Operation 1566 performs sending a radio program buy message for the selected radio program. Arrow 1568 directs execution from operation 1566 to operation 1570 . Operation 1570 terminates the operations of this flowchart. Arrow 1572 directs execution from operation 1562 to operation 1570 , whenever operation 1562 is not asserted (No).
[0098] [0098]FIG. 24 depicts another flowchart of operations controlling a vehicular radio-based program selection and ordering system in accordance with certain embodiments. Operation 1590 starts the operations of this flowchart. Arrow 1592 directs the flow of execution from operation 1590 to operation 1594 . Operation 1594 performs sensing a vehicle internal audio feedback channel to create a sensed vehicle audio feedback stream. Arrow 1596 directs execution from operation 1594 to operation 1598 . Operation 1598 performs processing the sensed vehicle audio feedback to create a processed vehicle audio feedback. Arrow 1500 directs execution from operation 1598 to operation 1502 . Operation 1502 terminates the operations of this flowchart.
[0099] [0099]FIG. 25 depicts a detail flowchart of operation 1412 of FIG. 18 determining selection of the sensed radio program in accordance to certain embodiments. Arrow 1620 directs the flow of execution from starting operation 1412 to operation 1622 . Operation 1622 performs determining the processed vehicle audio feedback to create the determined selection of the sensed radio program. Arrow 1624 directs execution from operation 1622 to operation 1626 . Operation 1626 terminates the operations of this flowchart.
[0100] [0100]FIG. 26 depicts a detail flowchart of operation 1562 of FIG. 22 determining to order the selected radio program in accordance to certain embodiments. Arrow 1640 directs the flow of execution from starting operation 1562 to operation 1642 . Operation 1642 performs determining the processed vehicle audio feedback to create the determined ordering of the selected radio program. Arrow 1644 directs execution from operation 1642 to operation 1646 . Operation 1646 terminates the operations of this flowchart.
[0101] [0101]FIG. 27 depicts a detail flowchart of operation 1416 of FIG. 18 displaying the radio program confirmation text in accordance to certain embodiments. Arrow 1670 directs the flow of execution from starting operation 1416 to operation 1672 . Operation 1672 performs audio processing the radio program confirmation text to create an audio radio program confirmation script. Arrow 1674 directs execution from operation 1672 to operation 1676 . Operation 1676 performs sending the audio radio program confirmation script to an audio output device. Arrow 1678 directs execution from operation 1676 to operation 1680 . Operation 1680 terminates the operations of this flowchart.
[0102] [0102]FIG. 28 depicts a detail flowchart of operation 1416 of FIG. 18 displaying the radio program confirmation text in accordance to certain embodiments. Arrow 1700 directs the flow of execution from starting operation 1416 to operation 1702 . Operation 1702 performs sending a buy query for the selected radio program. Arrow 1704 directs execution from operation 1702 to operation 1706 . Operation 1706 performs receiving a response to the selected radio program buy query. Arrow 1708 directs execution from operation 1706 to operation 1710 . Operation 1710 performs generating the radio program confirmation text from the selected radio program buy query response. Arrow 1712 directs execution from operation 1710 to operation 1714 . Operation 1714 terminates the operations of this flowchart.
[0103] [0103]FIG. 29 depicts a detail flowchart of operation 1416 of FIG. 18 displaying the radio program confirmation text in accordance to certain embodiments. Arrow 1730 directs the flow of execution from starting operation 1416 to operation 1732 . Operation 1732 performs presenting said radio program confirmation text to a visual output device. Arrow 1734 directs execution from operation 1732 to operation 1736 . Operation 1736 terminates the operations of this flowchart.
[0104] [0104]FIG. 30 depicts another flowchart of operations controlling a vehicular radio-based program selection and ordering system in accordance with certain embodiments. Operation 1750 starts the operations of this flowchart. Arrow 1752 directs the flow of execution from operation 1750 to operation 1754 . Operation 1754 performs initializing use for a specific user to create a signature for the specific user. Arrow 1756 directs execution from operation 1754 to operation 1758 . Operation 1758 terminates the operations of this flowchart. Arrow 1760 directs the flow of execution from starting operation 1750 to operation 1762 . Operation 1762 performs initializing a usage session for a first user utilizing the signature for the specific user. Arrow 1764 directs execution from operation 1762 to operation 1758 . Operation 1758 terminates the operations of this flowchart.
[0105] Note that operations 1754 and 1762 may be selected through a number of different mechanisms, including but not limited to pushing buttons.
[0106] [0106]FIG. 31 depicts a detail flowchart of operation 1762 of FIG. 30 initializing a usage session for a first user utilizing the signature for the specific user in accordance to certain embodiments. Operation 1780 starts the operations of this flowchart. Arrow 1782 directs the flow of execution from operation 1780 to operation 1784 . Operation 1784 performs sampling the first user response to create a first user signature. Arrow 1786 directs execution from operation 1784 to operation 1788 . Operation 1788 performs comparing the first user signature with the signature of the specific user to create a signature comparison. Arrow 1790 directs execution from operation 1788 to operation 1792 . Operation 1792 performs blocking access by the first user whenever the comparison is non-matching. Arrow 1794 directs execution from operation 1792 to operation 1796 . Operation 1796 terminates the operations of this flowchart.
[0107] [0107]FIG. 32 depicts a detail flowchart of operation 1790 of FIG. 31 blocking access by the first user whenever the comparison is non-matching in accordance to certain embodiments. Arrow 1810 directs the flow of execution from starting operation 1790 to operation 1812 . Operation 1812 performs sending a stolen device report based upon the first user signature. Arrow 1814 directs execution from operation 1812 to operation 1816 . Operation 1816 terminates the operations of this flowchart.
[0108] [0108]FIG. 33 depicts a high level system block diagram showing a computer with several forms of memory which in different embodiments provide residence for programs implementing the disclosed and claimed methods of controlling a vehicular radio. Computer 1830 is coupled to Computer Readable Memory 1840 by read access operations as indicated by arrow 1842 . At least one program implementing the method according to the present invention of controlling a vehicular radio may reside in this memory 1842 in accordance with certain embodiments. In certain further embodiments, at least one program implementing the method according to the present invention may reside in a first non-volatile memory 1846 , contained within the memory domain of computer readable memory 1840 . Some or all of this first non-volatile memory 1846 , as well as some or all of the computer readable memory 1840 may be successfully accessed by write operations as indicated by the arrow 1844 from computer 1830 . Certain preferred embodiments of the above memory system include but are not limited to RAM, battery backed up RAM, nonvolatile semiconductor memory, combinations of RAM and nonvolatile semiconductor memory, as well as RAM and disk memory of various kinds. Nonvolatile memory includes but is not limited to one or more devices embodying ROM, EPROM, EEPROM or Flash EEPROM memory technology as well as disk memory including both electromagnetic and optical recording media.
[0109] The coupling access operations 1842 and 1844 may be carried out using a variety of mechanisms including but not limited to computer busses and addressable port communication schemes. Computer busses include but are not limited to multiplexed address and data busses, demultiplexed address and data busses, as well as encoded multiplexed address data busses. Multiplexed computer busses share bus resources for the address and data signals so that most operations involve separate bus states to transfer address and data signals. A number of solid-state disk busses are examples of multiplexed address and data bus. Demultiplexed address and data busses do not share bus resources for the address and data signals allowing for address and data signals to be transferred in a single bus state. PCI bus is an example of such a demultiplexed address and data bus. Encoded multiplexed address and data buses encode these address and data signals so that several bus states are required to transfer at least some of the address or data signals. USB (Universal Serial Bus) is an example of an encoded multiplexed address and data bus. Computer 1830 is further coupled to a second nonvolatile memory 1850 in a fashion supporting read operations as indicated by arrow 1852 . This second nonvolatile memory 1850 may provide the residence of at least one program implementing the disclosed and claimed methods of controlling a vehicular radio. In certain further embodiments, the second nonvolatile memory 1850 may be written as indicated by arrow 1854 from computer 1830 .
[0110] A removable storage device 1860 engaged 1864 with removable storage interface 1862 and readably coupled 1866 to computer 1830 provides a residence for at least one program implementing the disclosed methods of controlling a vehicular radio in accordance with certain embodiments.
[0111] [0111]FIG. 34 depicts a summary flowchart of using a vehicular radio-based program selection and ordering system in accordance with an embodiment. Operation 1900 starts the operations of this flowchart. Arrow 1902 directs the usage from operation 1900 to operation 1000 . Operation 1000 performs operations discussed with regards to FIG. 4 above. Arrow 1904 directs the usage from operation 1000 to operation 1906 . Operation 1906 terminates the operations of this flowchart.
[0112] Arrow 1910 directs the usage from starting operation 1900 to operation 1120 . Operation 1120 performs operations discussed regarding FIG. 9. Arrow 1912 directs the usage from operation 1120 to operation 1906 . Operation 1906 terminates the operations of this flowchart.
[0113] Arrow 1920 directs the usage from starting operation 1900 to operation 1190 . Operation 1190 performs operations discussed regarding FIG. 12. Arrow 1922 directs the usage from operation 1190 to operation 1906 . Operation 1906 terminates the operations of this flowchart.
[0114] Arrow 1930 directs the usage from starting operation 1900 to operation 1230 . Operation 1230 performs operations discussed regarding FIG. 14. Arrow 1932 directs the usage from operation 1230 to operation 1906 . Operation 1906 20 terminates the operations of this flowchart.
[0115] Arrow 1940 directs the usage from starting operation 1900 to operation 1270 . Operation 1270 performs operations discussed regarding FIG. 16. Arrow 1942 directs the usage from operation 1270 to operation 1906 . Operation 1906 terminates the operations of this flowchart. FIG. 35 depicts a summary flowchart of operations controlling a vehicular radio-based program selection and ordering system in accordance with certain embodiments. Operation 1950 starts the operations of this flowchart. Arrow 1952 directs the flow of execution from operation 1950 to operation 1400 . Operation 1400 performs operations discussed regarding FIG. 18. Arrow 1954 directs execution from operation 1400 to operation 1956 . Operation 1956 terminates the operations of this flowchart.
[0116] Arrow 1960 directs the flow of execution from starting operation 1950 to operation 1590 . Operation 1590 performs operations discussed regarding FIG. 24. Arrow 1962 directs execution from operation 1590 to operation 1956 . Operation 1956 terminates the operations of this flowchart.
[0117] Arrow 1970 directs the flow of execution from starting operation 1950 to operation 1750 . Operation 1750 performs operations discussed regarding FIG. 30. Arrow 1972 directs execution from operation 1750 to operation 1956 . Operation 1956 terminates the operations of this flowchart.
[0118] Note that direction of execution to these operations may be achieved by a variety of mechanisms, including but not limited to the pushing of buttons and selection of menu options, possibly as part of an event processing mechanism within an application running on an event driven real-time operating system.
[0119] [0119]FIG. 36 depicts a system block diagram of a radio for receiving a radio program data channel, and conducting transactions in accordance with certain embodiments. An embedded controller 2000 is shown including a computer readable memory 1840 containing a writeable non-volatile memory component 1846 . A receiver 2002 of said radio program data channel is coupled 2004 to the embedded controller 2000 generating a radio program data channel stream readably accessible by the embedded controller.
[0120] A radio transceiver 2010 is coupled to the embedded controller 2012 receiving from the embedded controller transaction output messages. The radio transceiver 2010 generates a transaction input stream 2014 readably accessible by the embedded controller 2000 .
[0121] A user interface circuit 2020 is coupled to said embedded controller 2000 generating user selection data readably accessible 2024 by said embedded controller. The user interface circuit 2020 receives 2022 from said embedded controller 2000 user output data.
[0122] [0122]FIG. 37 depicts a detail system block diagram system block 2002 , a receiver of the radio program data channel as shown in FIG. 36 in accordance with certain further embodiments. The radio further includes an external IF signal input port 2034 . The radio program data channel receiver 2002 includes a radio program data channel 15 isolator 2030 containing an input port 2038 coupled 2032 to said external IF input signal port 2034 . The radio program data channel isolator 2030 further contains a digital output port 2038 coupled 2004 to the embedded controller 2000 providing the radio program data channel stream.
[0123] In certain embodiments the external IF signal input port 2034 may be derived from the output 110 of FM IF stage 108 , as required for reception of the RDBS sub-band. In certain alternative embodiments, the external IF signal input port 2034 may be derived from a different signal protocol transmitted independently of standard FM broadcasts. Such alternative embodiments include but are not limited to other applications AM, FM, Frequency Division Multiple Access (FDMA), Time Division Multiple Access (TDMA), Wavelet Division Multiple Access, various spread spectrum techniques including but not limited to direct sequence (CDMA), Wideband CDMA employing both spreading and scrambling codes, frequency hopping and time hopping.
[0124] [0124]FIG. 38 depicts a detail system block diagram of radio program data channel isolator 2030 as shown in FIG. 37 in accordance with certain further embodiments wherein the external IF signal input port supports an analog signal protocol. The radio program data channel isolator 2032 includes an analog isolation circuit 2050 . The analog isolation circuit 2050 includes a first analog input port coupled 2044 to the external IF input port 2036 and a first digital output port coupled 2048 to the radio program data channel isolator digital output. The analog isolation circuit 2050 further includes an A/D converter 2040 further comprising a second analog input port 2042 coupled 2044 to the first analog input port and a second digital output port 2046 coupled 2048 to the first digital output port.
[0125] [0125]FIG. 39 depicts a detail system block diagram of analog isolation circuit 2050 as shown in FIG. 38 in accordance with certain further embodiments wherein the external IF signal input port supports an analog signal protocol. The analog isolation circuit 2050 includes bandpass filter 2060 containing an input port 2062 coupled 2064 to the external IF input signal 2036 and further containing a output port 2066 coupled 2068 to the A/D converter input port 2042 .
[0126] [0126]FIG. 40 depicts a detail system block diagram of user interface 2020 as shown in FIG. 36 in accordance with certain embodiments supporting a user interface audio output interface 2080 providing 2082 , 2084 audio output 2086 of the user output data. Note that in certain embodiments, user interface audio output interface 2080 can provide a digital interface. In certain alternative embodiments, user interface audio output interface 2080 can provide an analog interface. In certain embodiments, user interface audio output interface 2080 can provide feed 2084 a mixer. In certain embodiments, user interface audio output interface 2080 can provide feed 2084 a multiplexer.
[0127] [0127]FIG. 41 depicts a detail system block diagram of user interface 2020 as shown in FIG. 36 in accordance with certain embodiments supporting a user interface audio input sensor 2100 providing 2024 an user audio input data stream to the embedded controller 2000 . Note that in certain embodiments, audio input sensor 2100 may include an A/D converter coupling audio input 2102 to output coupling 2024 . In certain further embodiments, audio input sensor 2100 may further include an amplifier coupled between the A/D converter and audio input 2102 . In certain further embodiments, audio input sensor 2100 may further include a filter coupled between the A/D converter and the audio amplifier.
[0128] [0128]FIG. 42 depicts a detail system block diagram of user interface 2020 as shown in FIG. 36 in accordance with certain embodiments supporting a visual output device 2100 providing visual output 2122 of the user output data 2022 . The visual output device 2100 in certain embodiments includes but is not limited to a Light Emitting Diode Device (LED), which may further include a multiplicity of Light Emitting Diode components. The visual output device 2100 in certain embodiments may include but is not limited to a flat panel display device such as found in a variety of calculators, handheld computers and notebook computers.
[0129] [0129]FIG. 43 depicts a detail system block diagram of user interface 2020 as shown in FIG. 36 in accordance with certain embodiments supporting a user interface tactile input sensor 2140 providing an user tactile input data stream 2024 . FIGS. 44 and 46 demonstrate two embodiments of devices included in user interface tactile input sensor 2140 providing tactile input support. Such figures are not meant to limit the scope of user tactile input, but rather to provide examples advantageous in certain applications. Other examples include but are not limited to touch pads and proximity sensors.
[0130] [0130]FIG. 44 depicts a detail system block diagram of user interface tactile input sensor 2140 as shown in FIG. 43 in accordance with certain embodiments supporting a user interface tactile input sensor 2140 including a button sensor 2160 . Button sensor 2160 includes a button input port 2166 coupled 2164 to button input 2162 . In certain embodiments, button input 2162 includes multiple buttons and an interface circuit. In certain embodiments, button input 2162 included button debounce circuitry. In certain embodiments, button input 2162 provides a binary state value related to pushing or not pushing the related button. In certain embodiments, button input 2162 further provides more detailed motion related information, such as key acceleration and release.
[0131] [0131]FIG. 45 depicts a detail system block diagram of user interface tactile input sensor 2140 as shown in FIG. 43 in accordance with certain embodiments supporting a user interface tactile input sensor 2140 including a fingerprint scanner 2180 . The coupling 2184 of user finger 2182 to input port 2186 of fingerprint scanner 2180 may include a CCD array in certain embodiments. In certain further embodiments, inut coupling 2184 may further include a pressure sensor to indicate when user finger 2182 is positioned for a fingerprint scan. In certain alternative embodiments, input port 2186 may include a CCD array.
[0132] [0132]FIG. 46 depicts a detail system block diagram of radio transceiver 2010 as shown in FIG. 36 in accordance with certain embodiments supporting the radio transceiver 2010 including a cellular telephone 2200 . Cellular telephone 2202 is coupled 2204 to | A method of use provides an extremely efficient manner of ordering a radio program occurring at approximately the time presented, minimizing the need to remember any details: The method is embodied in a range of tactile and voice controls which people in motion need to have. Security options include voice signatures, button sequences and fingerprint identification. User feedback is embodied in both audio and visual display formats. A method of controlling a radio is claimed which provides for placing an order, querying the ordering system for additional information, initializing a user's identifying signature, initializing a session by identifying a user, if the user is not properly identified, blocking access to ordering, and in certain embodiments, calling the police. A radio device is claimed supporting an IF signal source containing essential information on the radio program, an embedded controller, user interface as well as a radio transceiver by which the ordering transaction is carried out. | 7 |
CROSS-REFERENCE
This application is a divisional of U.S. application Ser. No. 13/482,244, filed May 29, 2012, and claims the benefit of U.S. Provisional Application Ser. No. 61/492,110, filed Jun. 1, 2011, the entirety of which is hereby incorporated by reference.
TECHNICAL FIELD
The present disclosure relates to a method of converting a gas burner from an open top arrangement to an infrared radiant burner system, and the resulting apparatus.
BACKGROUND
Gas fired cooking ranges have achieved wide acceptance in both residential and commercial kitchens. A known design for gas fired cook tops in ranges includes separate burner assemblies for each cooking location, with each burner assembly including a venturi and a burner head having gas-emitting orifices. A grate or other surface is often positioned above the burner head and venturi to provide a surface for pots, pans, other cooking vessels, or food products.
Factors such as flame intensity and efficiency, burner assembly cleanability, and fuel consumption efficiency are important to both residential and commercial installations. The time required for completing a food course, including initial preparation time for heating and actual cooking time, can be reduced by efficient burner performance and heat transfer to the cooking vessel atop the burner.
This arrangement is traditionally considered inefficient as the system heats the air around the grate, eventually transferring heat to the pot, pan, or food product placed thereon. A more efficient system is that described in U.S. Pat. No. 7,726,967, that describes a gas-fed infrared burner. Gas-fed infrared burners are more efficient than similar open-top gas-fired burners, and therefore their use reduces energy consumption while improving cooking times.
An infrared radiant burner stovetop assembly is an expensive replacement for an open-top gas burner and may require substantial modification of the kitchen, stovetop, and cooking arrangement.
Therefore, there is a need in the art for an improved method and apparatus for replacing an open-top gas burner arrangement with an infrared radiant burner arrangement.
SUMMARY
Described herein is a method for modifying an open-top burner system to a radiant burner system. This modification is achieved by providing a stovetop having an open top burner system that includes a grate, burner head, and a venturi burner. The venturi burner includes an open top annular channel about a central opening. Further provided are a central hole plug, an emitter, and a radiant burner head assembly. To modify the stovetop, the grate and burner head are removed from the stovetop and the central plug is used to block (substantially or entirely) airflow through the central opening of the venturi burner. The radiant burner head assembly is next positioned over the venturi burner and the emitter is positioned over the radiant burner head assembly. This series of steps converts the assembly from a traditional open-top burner system to a radiant burner system.
According to various further embodiments, the radiant burner head assembly may include a plenum and a perforated member. The radiant burner head assembly may further include a spacer for separating two or more perforated members. According to another embodiment, the stovetop may include a support for supporting the grate that is used to support the emitter.
Also disclosed is an apparatus or kit for converting a traditional open top burner system to a radiant burner system. The traditional open top burner system generally includes a venturi burner with a central opening, a burner head, and a grate. The apparatus or kit includes a plug for blocking secondary air flow through the central opening, a radiant burner head assembly that is sized to rest on the venturi burner, and an emitter that replaces the grate.
According to various further embodiments, the radiant head assembly may include a plenum with an opening for fitting over the venturi burner. The radiant head assembly may also include one or more perforated members and one or more support members. The support members may be positioned between adjacent perforated members. According to yet another embodiment, the radiant burner assembly may include baffle and burner assemblies.
The details of one or more embodiments are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will be apparent from the description and drawings, and from the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of one embodiment of a gas cooking range;
FIG. 2 is a perspective view of one embodiment of a duel burner head unit;
FIG. 3 is an exploded partial view of one embodiment of an open top burner system;
FIG. 4 is an exploded partial view of one embodiment of a radiant burner system;
FIG. 5 is a side cutaway or cross-section of one embodiment of the assembled radiant burner system;
FIG. 6 is an exploded view of one embodiment of the radiant burner head assembly;
FIG. 7 is a side cutaway or cross-section of one embodiment of the radiant burner head assembly and an open top burner assembly in a dual burner head unit.
DETAILED DESCRIPTION
Referring to FIG. 1 , numeral 100 designates a gas cooking range having a cooktop 102 with multiple cooking locations 104 (e.g., six in the illustrated embodiment, 3 front and 3 back) with associated burner heads. In one embodiment, pairs of burner heads are formed by burner head assemblies 106 (see FIG. 2 ), but each burner head could be formed and fed with gas on an individual basis. Range 100 further includes an oven chamber 118 beneath the cooktop area. The range 100 may be a commercial range or a residential range, taking on a variety of configurations, of which FIG. 1 is merely exemplary.
Range 100 includes a gas circuit for supplying combustible gas to each burner head and to an oven burner assembly (not shown). The gas circuit includes a plurality of flow control valves 110 provided for initiating, terminating, and controlling the rate of gas flow to cooking locations 104 on cook top 102 . Various valve configurations and gas flow circuits could be used. Illustrated range 100 is supported on casters 112 , by which range 100 can be moved a short distance to clean the area around the range. However, embodiments without casters are contemplated.
Exemplary burner head assembly 106 includes a first burner head 120 and a second burner head 122 at which combustion of gaseous fuel occurs. A single piece, monolithic casting 124 forms a first venturi 126 associated with or feeding a first burner head base 128 and a second venturi 130 associated with or feeding a second burner head base 132 . The burner head base 128 , 132 may be alternatively referred to as a venturi burner. First venturi 126 and second venturi 130 provide a flow of gas and primary combustion air for combustion at first and second burner heads 120 , 122 , respectively, in front and back locations, respectively, on cook top 102 . First and second gas receivers 134 , 136 , are provided on first venturi 126 and second venturi 130 , respectively. Each receiver 134 , 136 is aligned and/or connected with a different control valve 110 to receive gas therefrom when the control valve 110 is opened to allow gas to flow therethrough. Receivers 134 , 136 also admit a flow of ambient air to mix with the combustible gas in first venturi 126 and second venturi 130 to provide a combustible mixture to burner heads 106 , 122 .
FIG. 2 illustrates burner head assembly 106 in a partial state of disassembly. Each burner head base 128 , 132 may be a substantially annular body defining an open top annular channel 138 between an inner wall 140 and an outer wall 142 . Annular channel 138 of burner head base 128 is visible in FIG. 2 . Prior to conversion, burner head cover 144 may be provided on each burner head base 128 , 132 , with cover 144 on burner head base 132 being shown in FIG. 2 . Each cover 144 has a plurality of gas-emitting orifices 146 therein through which a mixture of combustible gas and primary combustion air is emitted. The inner wall 140 further surrounds a central opening 141 that provides an upward secondary air flow to the combustion space. This central opening 141 may include a restrictor plate (shown as 143 for head 122 ) that meters or regulates air flow.
FIG. 3 illustrates an exploded view of cooking locations 104 on cook top 102 . Positioned above each burner head assembly 106 is a grate 148 that allows for placement of a cooking apparatus (not shown) above the burner assembly 106 . The cooking apparatus may be a pot, pan, rotisserie, or other apparatus useful in the cooking of food products (not shown). Alternatively, food may be positioned directly on or above the grate 148 , foregoing the use of cooking apparatus. As further shown in FIG. 3 , the grate 148 may be positioned on supports 150 , 152 sized to support grate 148 over the burner assembly 106 . As shown in FIG. 2 , burner head cover 144 is positioned on burner head base 132 to evenly distribute a flame for cooking on grate 148 . In order to convert a given open top burner to a radiant burner system, the grate 148 and burner head cover 144 are removed from the applicable cooking location 104 .
Conversion of the burner system is further illustrated in FIG. 4 . As shown, the grate 148 and burner head cover 144 have been removed. Any regulating restrictor plate over the central opening 141 is also preferably removed, along with any associated igniter that is secured to the restrictor plate. The central opening 141 is plugged with a center hole plug 154 that prevents or severely restricts the ability of secondary air to flow upward through the opening 141 . Next, a radiant burner head assembly 156 is positioned on the burner head base 132 so that gas flow is directed upward into and through the radiant burner head assembly 156 . Finally, an emitter 158 is positioned on the supports 150 , 152 , overlapping or covering the radiant burner head assembly 156 .
FIG. 5 illustrates a side cutaway of the completed radiant burner assembly. As shown in this figure, the center hole plug 154 covers the central opening 141 of the burner head base 132 , preventing or limiting airflow therethrough. In the illustrated embodiment, the center hold plug includes a cylindrical wall portion 155 having a bottom edge that rests upon an inner annular supporting ledge 153 of the burner head base, but other configurations are possible. The plug may be sized for a friction tight fit within the central opening 141 . The radiant burner head assembly 156 is positioned on the burner head base 132 so that gas flow through the burner head base 132 enters the radiant burner head assembly 156 . Finally, the emitter 158 has been positioned on the supports 150 , 152 and surrounds the radiant burner head assembly 156 so that heat is transferred directly to the emitter 158 .
FIG. 6 illustrates an exploded view of the radiant burner head assembly 156 . The radiant burner head assembly 156 generally includes a plenum housing 160 , one or more perforated members 162 and one or more support members 164 (e.g., mounting members). As described in U.S. Pat. No. 7,726,967 to Best, herein incorporated by reference in its entirety, the perforated 162 and support members 164 may be stacked in alternating layers to dissipate heat to the emitter 158 ( FIG. 5 ). In accordance with the exemplary embodiment, each of the perforated members 162 may be fabricated from a nonwoven plate of high temperature metal alloy so that it defines a multiplicity of holes or perforations 56 that extend completely therethrough.
The plenum housing 160 generally consists of a base 166 including a burner opening 168 , which in the illustrated embodiment is sized and adapted to fit over and rest upon an outer annular supporting ledge 151 of the burner head base 132 ( FIG. 5 ). However, other configurations for supporting the plenum housing in relation to the burner head base could be used (e.g., feet that extend downward from the housing base and into the annular channel of the burner head base, or supports that extend radially outward from the plenum housing and engage some structure on the range top). In the illustrated embodiment, the plenum housing base 166 is surrounded by upward and outward sloping walls 170 defining a volume of the plenum. As further detailed in the Best '967 patent, combustible gas and air are supplied into the plenum 160 and pass through one or more of the perforated members 162 before being combusted. This combustion serves to heat the emitter 158 ( FIG. 5 ) which in turn is used in cooking food items.
According to one embodiment, the perforated members 162 and support members 164 are connected to the plenum 160 to form a single piece radiant burner assembly 156 . This single unit provides a single piece for assembly and makes conversion easier. Alternatively, the perforated members 162 and support members 164 may be secured to one another and constitute a single sheaf that may be easily inserted into the plenum housing 160 during assembly and replaced if necessary during the life of the radiant burner system. It is also contemplated that in another embodiment the plug 154 could be supported within the plenum housing 160 (e.g., via connection to the housing 160 ) so as to automatically seal the opening 141 when the plenum housing 160 is placed upon the burner head base and/or support the plenum housing in relation the burner head base. In addition, the radiant burner head assembly may, for example, include an associated igniter mounted thereon (e.g., connected to an external surface of the housing 160 ) with associated wiring to be connected to the existing range wiring, or the radiant burner head assembly may simply include an igniter mount adapted to receive the pre-existing igniter of the open-top burner head assembly to properly position the igniter to ignite gases leaving the top of the radiant burner head assembly.
FIG. 7 illustrates a side cutaway of a cooktop 102 including a traditional open top burner system and a radiant burner system. As shown in this view, in converting the traditional system to a radiant system the burner head cover 144 and grate 148 have been removed. A center hole plug 154 has been placed in the central opening 141 of the burner head base 132 and a radiant burner head assembly 156 has been positioned over the burner head base 132 . Finally, an emitter 158 has replaced the grate 148 .
Variations and modifications of the described apparatus will be appreciated by those having skill in the art. For example, the radiant burner head 156 may vary in size or design according to the size, shape, and location of the burner head base 132 in the cooktop 102 . The emitter 158 may also vary in size, shape, or design according to the position of supports 150 , 152 . The emitter 158 is preferably designed to engage the supports 150 , 152 in the same manner as the grate 148 of the traditional open top burner system, therefore allowing for easy conversion between a traditional open top burner system and the preferred radiant burner system. Further, as described in Best '967, the materials for the perforated members 162 , support members 164 , plenum 160 , and emitter 158 may vary according to demand.
It is to be clearly understood that the above description is intended by way of illustration and example only, is not intended to be taken by way of limitation, and that other changes and modifications are possible. | A method for modifying an open-top burner system to a radiant burner system involves providing a stovetop having an open top burner system which includes a grate, burner head, and a venturi burner. The venturi burner includes an open top annular channel about a central opening. Further provided are a central hole plug, an emitter, and a radiant burner head assembly. To modify the stovetop, the grate and burner head are removed from the stovetop and the central plug is used to block airflow through the central opening. The radiant burner head assembly is next positioned over the venturi burner and the emitter is positioned over the radiant burner head assembly. This series of steps thereby converts the assembly from a traditional open-top burner system to a radiant burner system. A kit may be provided to facilitate the process. | 5 |
TECHNICAL FIELD
[0001] This invention relates to heat exchangers, such as vehicle engine cooling radiators, and to a flow control valves therefore control valve that is integrated into the inlet of a U flow type radiator in a simple and non flow restrictive fashion.
BACKGROUND OF THE INVENTION
[0002] Flow control in vehicle engine cooling radiators has historically consisted of just a passively acting thermostat which, reacting to coolant temperature, blocks flow into the radiator to a greater or lesser degree, by passing the remainder of the flow through an by pass path external to the radiator. When wide open at the highest coolant temperature, all flow goes through the radiator. This standard system does not offer a high degree of control, generally using a thermally expandable wax material. Other systems attempt to add an extra degree of control by deliberately and externally heating the wax material to expand it, generally electrically heating it. There has been a recent trend, at least in published patents, toward active, electronically controlled flow control valves. An example may be seen in U.S. Pat. No. 6,314,920. The system shown there requires an electronically controlled coolant pump, and the valve is also external to the radiator, requiring an external by pass circuit around the radiator.
[0003] Other patents show control valves internal to the header tanks of the radiator, either passively or actively operated. One example is U.S. Pat. No. 5,305,826 shows a plunger operated double valve, either actively or passively controlled, that simultaneously blocks or opens both the inlet into a radiator of the two pass type, as well as blocking or opening a by pass passage between the two passes. As disclosed, the valve, being just downstream of the inlet, would represent a severe flow restriction within the header tank, in addition to the pressure drop that inherently happens as flow enters a header tank inlet and makes a ninety degree turn. Likewise, U.S. Pat. No. 4,432,410 shows a passively acting by pass valve located within the header tank, just downstream of the inlet. This, also, would represent a significant additional flow restriction and pressure drop. Coolant flow induced pressure drop through the inlet, outlet and header tank of a radiator is a serious issue, and features that add significantly to it are not preferred, despite the desirability of having an internal flow control valve, as opposed to an external flow control valve.
SUMMARY OF THE INVENTION
[0004] The invention provides an actively controllable radiator flow control valve that is internal to the radiator header tank, but which is integrated therewith in such a way as to not add a large pressure drop.
[0005] In the embodiment disclosed, the radiator is a U flow design, with two rows of flow tubes, in which one header tank is split between inlet and outlet portions by a dividing wall, with the inlet on one side and the outlet/pump inlet on the other side. The other header tank would act only to return the flow from the inlet to outlet portion of the first header tank. The physical coolant inlet to the first header tank is a cylindrical barrel that extends not only outside of the tank, as a conventional inlet fitting would, but also through the dividing wall and across the whole width of the interior of the tank. The exterior, outer end of the barrel provides the coolant inlet to the tank, while the inner surface provides a stationary outer housing and guide for the movable inner member of the control valve. Windows in the barrel allow open into the inlet and outlet side of the first header tank, one on either side of the dividing wall. The movable portion of the valve is a hollow cylindrical sleeve, closely and rotatably mounted within the outer barrel. One end of the sleeve opposite the inlet end of the outer barrel, can be turned back and forth about its central axis by a motor or similar actuator. Cut outs in the inner sleeve register with the windows in outer barrel, either completely or partially, or not at all, depending on the relative turned position of the inner sleeve.
[0006] Coolant flow entering the exterior end of the outer barrel then flows inside the close fitting inner sleeve, essentially just as it would with a conventional radiator tank inlet, and with no significant additional pressure loss. Depending on the relative registration of the inner sleeve and outer barrel cut outs and widows, flow exits the inner sleeve, and flows into either just the outlet side of the header tank, for a complete by pass of the radiator, or just the inlet side of header tank, forcing all flow through the radiator, or a mixed flow. Mixed flow can constitute the normal radiator operation, as determined by sensed engine or coolant temperature and consequent cooling demand, rather than the conventional operation of total flow through the radiator at all times other than initial warm up. This is feasible since a U flow radiator is inherently more efficient and the valve adds little additional pressure drop. Operating the radiator normally with some degree of by pass saves pump work and energy, regardless of how the pump is driven. Total radiator flow can then be reserved for severe engine cooling requirements.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] [0007]FIG. 1 is perspective view of a radiator incorporating the flow control valve of the invention;
[0008] [0008]FIG. 2 is a perspective view of the inside of just the inlet/outlet or first header tank;
[0009] [0009]FIG. 3 is a disassembled view of the control valve and its actuator;
[0010] [0010]FIG. 4 is a perspective view of the inside of the upper end of the inlet/outlet tank, showing the flow control valve in a full by pass mode;
[0011] [0011]FIG. 5 shows the flow control valve in a mixed flow mode;
[0012] [0012]FIG. 6 shows the flow control valve in a full radiator flow mode.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0013] Referring first to FIGS. 1 and 2, a heat exchanger of the U flow type, in this case a vehicle engine cooling radiator, designated generally at 10 , is the U flow type, with a first, vertically oriented, inlet/outlet header tank, designated generally at 12 , a second or return tank 14 , and regularly spaced pairs of flow tubes, two of which are shown at 16 . The pairs of flow tubes are separated by conventional, corrugated, air cooling fins 17 , brazed in place. External air flow across the outside of the tubes 16 is in the direction shown by the wavy arrow, while the internal coolant flow that is not by passed, as described below, flows in a U pattern from tank 12 , to 14 , and back. As seen in FIG. 2, the coolant flow pattern is determined by a dividing wall 18 that runs the length of the inside of first tank 12 , mating in sealed fashion to the inside of a header plate 20 to divide tank 12 into a front, coolant inlet side I and a rear, coolant outlet side O. Thus, the rear “half” of radiator 10 (the rear set of tubes 16 ) sees the hottest coolant as well as the hottest air flow (air which has already flowed over the front “half” of radiator 10 ) while the front “half” of radiator 10 (the front set of tubes 16 ), in which the coolant flow has already been partially cooled sees the coolest air flow. This provides the most thermally efficient pattern of air-coolant temperature differentials, and is inherently more efficient than a single flow radiator. The invention works in conjunction with this internal structure of header tank 12 to provide an improved flow control valve, so as to take even more advantage of the inherent thermal efficiency advantage of the U flow pattern.
[0014] Still referring to FIGS. 2 and 3, the coolant inlet fitting for the first tank 12 is, to all external appearances, a conventional, hollow cylindrical stub pipe 22 to which a coolant hose would be clamped. Normally, such a stub pipe 22 would do nothing but open through the outer wall of tank 12 , at about ninety degrees thereto, and open only into the inlet side I of tank 12 . Given the ninety degree turn that the coolant flow makes at and through the tank wall, a significant pressure drop is inevitable. In the embodiment of the invention disclosed, however, the sub pipe 22 is, in effect, the exterior protrusion of a hollow cylindrical barrel, indicated generally at 24 , that extends through one side wall of tank 12 , across and through the entire width of the header tank 12 , protruding slightly at the opposed side wall (as best seen in FIG. 3), but which is open to the exterior of tank 12 only at the stub pipe portion 22 . Barrel 24 , in and of itself, being essentially just an extension of the hollow cylindrical stub pipe 22 , would not add any additional pressure drop, but, in the absence of other provisions, would also not allow any coolant inflow. However, additional structural features, described below, allow the barrel to provide both an inlet and part of a coolant flow control valve. Further down on first tank 12 , well below inlet 22 , is a pump housing 25 , which is open only to the outlet side O of tank 12 . As shown, housing 25 would contain a non illustrated electric pump, but the invention here is not limited to use of an electric pump only. The pump powers coolant flow so that, as coolant is pumped out of the outlet side I of first header tank 12 and into the non illustrated engine cooling jacket, coolant is pulled out of the cooling jacket and into pipe 22 , where its flow path within radiator 10 , prior to reaching the pump again is determined by additional structure described next.
[0015] Still referring to FIGS. 2 and 3, barrel 24 has two windows or cut outs 26 and 28 , each generally rectangular in a planar, projected view, and one located on either side of the dividing wall 18 , so as to open to the interior of the first header tank 12 in its inlet and outlet sides I and O respectively. Closely received inside of barrel 24 is a hollow cylindrical sleeve, indicated generally at 30 , with an open end 32 , a closed end 34 , and relatively thin wall through which a pair of axially spaced, diametrically opposed windows 36 and 38 are cut, also generally “rectangular”. The windows 36 and 38 are located near the open end 32 and closed end 34 respectively. Sleeve 30 is inserted into barrel 24 until its closed end 34 abuts with the protruding end of barrel 24 and its open end 32 faces and is concentric to inlet pipe 22 . Sleeve 30 's outer surface fits closely and turnably within the inner surface of barrel 24 , and would be maintained co extensive and co axial with barrel 24 if it were either rotated or moved axially back and forth. The thin wall of sleeve 30 reduces the inner diameter of barrel 24 only slightly, and it becomes, in effect, almost an extension of the inlet pipe 22 inserted within barrel 24 . At the opposed outer wall of tank 12 , a rotary type actuator 40 is mounted, which has an electric motor that turns a splined shaft 42 . Shaft 42 enters a through hole 44 in the back of barrel 24 and is inserted non turnably into a closed ended hole 46 in the closed end 34 of sleeve 30 . A suitable seal would surround shaft 42 so as to prevent any leakage out of barrel 24 . Sleeve 30 , turned within barrel 24 by actuator 40 , provides an improved coolant flow within radiator 10 , as described next.
[0016] Referring next to FIG. 4, during engine warm up, actuator 40 , based on a temperature signal or other indication of the warm up condition, would turn sleeve 30 within barrel 24 to the point shown, where the barrel cut out 26 is completely blocked by the wall of sleeve 30 , while the sleeve window 38 and barrel cut out 28 are fully registered and aligned. As a consequence, all coolant entering stub pipe 22 flows directly within sleeve 30 , with very little restriction or pressure drop, due to the coaxial orientation of sleeve 30 to both pipe 22 and barrel 24 , and its relatively thin wall. Coolant flows out of sleeve 30 only through window 38 into the outlet side O of first header tank 12 . From there, it would be pulled down and out of pump housing 25 , without ever flowing through the radiator tubes 16 . As such, the engine would be able to warm up quickly, with no need for a by pass flow path external to radiator 10 . Coolant flowing inside of sleeve 30 , and then turning 90 degrees to enter the tank outlet side O, would not undergo significantly more pressure drop than it would by just flowing through stub pipe 22 and into the interior of a regular tank. Thus, the sleeve 30 uniquely cooperates with barrel 24 (which is effectively an extension of pipe 22 ) to create the valving action at essentially no cost to performance. Benefits not only include the more rapid engine warm-up, but also a pre warming of the header tank 12 to reduce thermal stress later. As disclosed, the inlet side I becomes fully blocked only as the outlet side O becomes fully opened. However, the shape and orientation of window 38 could be changed so that cut out 24 remained blocked by sleeve 30 as window 38 registered progressively more or less with cutout 28 , so as to meter and regulate the degree of by pass flow.
[0017] Referring next to FIG. 5, as the engine warms up and some external heat rejection becomes necessary, actuator 40 turns sleeve 30 within barrel 24 until each sleeve window 36 and 38 is registered partially with a respective barrel cut out 26 and 38 . This allows some coolant flow into tank inlet side I, and some directly into outlet side O. That coolant flowing into inlet side I will flow through one row of tubes 16 , into return tank 14 and back through the other row of tubes 16 and into tank outlet side O, rejecting heat to the air flow in the process. During normal operation, post engine warm up, but not under extreme conditions, it is contemplated that there would always be some by pass flow directly into the tank inlet side O. As such, relatively more of the sleeve window 38 , and relatively less of the sleeve widow 36 , would be open than is shown in FIG. 5. Again, this could be provided by how far actuator 40 turned sleeve 30 within barrel 24 , as based on coolant temperature or other sensed parameters. The inherent efficiency of the U flow radiator design shown is such that some radiator cooling capacity could normally be held “in reserve” for extreme conditions. This, as opposed to the normal radiator flow pattern where all coolant flow fully through the radiator once engine warm up is completed.
[0018] Referring finally to FIG. 6, in the case of extreme conditions where more than normal cooling capacity was needed, then sleeve 30 would be turned so as to fully block the barrel cut out 28 in the tank outlet side O, and to fully register the sleeve window 36 with the barrel cut out 26 in the tank inlet side I. Now, all flow runs through the radiator tubes 16 and back, and none is by passed, for maximum cooling capacity. Again, it is not contemplated that this would be the normal radiator flow path, as in a conventional radiator.
[0019] Variations in the disclosed embodiment could be made within the spirit of the invention. A downflow design with top and bottom tanks, rather than vertical tanks, could be used. The radiator could be divided up into a U flow pattern in a side to side, rather than the back to front, design shown. That is, the divider wall 18 could run across the center width of the tank 12 , rather than lengthwise. A similar sleeve turning within a similar barrel that opened into both the inlet and outlet sides of the tank would provide the same controlled flow advantages. Other shapes could be provided for the barrel cut outs and sleeve windows, other than the rectangular (in projection) shape disclosed, such as triangular, trapezoidal, etc, which would provide even more control of the flow rates as the sleeve turned to progressively register and align the two. Since one of the main advantages is the close fit of the sleeve within the barrel, coaxial to both the barrel and the inlet pipe, with the attendant low pressure drop, it would be theoretically possible to move a similarly close fitting sleeve axially back and forth within the barrel so as to align and misalign, block and un block, matching windows and cut outs. This could create a similar flow pattern. However, the rotary action shown is convenient and compact, and there are existing rotary actuators that would serve that purpose well. Potentially, a combination of both axial plunging and rotary turning could be used, since both motions would be well guided by the close fit of hollow cylindrical sleeve within cylindrical barrel. | A U flow radiator 10 with a header tank 12 split into inlet and outlet sides I and O by a lengthwise divider wall 18 has a coolant inlet consisting of a cylindrical pipe 22 . A hollow cylindrical barrel 24 co extensive and coaxial with pipe 22 and extending across divider wall 18 , with cut outs 26 and 28 opening respectively into both sides I and O. A thin walled, hollow cylindrical sleeve 30 turns within barrel 24 with windows 36 and 38 that alternately block or open the cut outs 26 and 28 , or open both partially. A rotary actuator 40 turns sleeve 30 within barrel 24 . Coolant can be selectively routed all to the tank outlet side O, by passing the radiator 10 for quick warm up. After warm up, coolant can be routed to I or O in desired proportions to increase or decrease cooling capacity. With high engine cooling demand, all coolant is routed to the inlet side I and all coolant passes through radiator 10. | 8 |
BACKGROUND
[0001] The invention generally relates to a system and method for obtaining and analyzing well data. In particular, the invention relates to a system and method for obtaining permanent gauge data from a well and analyzing such data in order to determine trends of the reservoir that is linked to the well.
[0002] It is now becoming common to deploy sensors within oil and gas wells in order to obtain relevant data from the wells, such as temperature, pressure, and flow rate (to name a few). Once retrieved, the data is analyzed to diagnose the well.
[0003] To date, prior art systems have either performed only the retrieval of the data or only the analysis of the retrieved data. No prior art system exists which both retrieves the data from the well and also automatically analyzes such data to diagnose the well and to indicate trends in the relevant reservoir and well.
[0004] Moreover, prior art systems called “well test analysis tools” exist which characterize a wellbore or a reservoir thereby providing relevant information and parameters of such wellbore or reservoir to a user. These well test analysis tools are very robust and typically take a substantial amount of time to conduct and complete the analysis of one wellbore or reservoir. It is often difficult to determine which wellbores and reservoirs should be subjected to a well test analysis. In order to save money and time, it would be beneficial to be able to quickly screen which wellbores or reservoirs should be subjected to the time consuming well test analysis.
[0005] Thus, there exists a continuing need for an arrangement and/or technique that addresses one or more of the problems that are stated above.
SUMMARY
[0006] According to a first aspect, the present invention consists of a method to retrieve and analyze data from a wellbore, comprising: locating at least one sensor in the wellbore or in communication with fluids produced from the wellbore; measuring at least one parameter of interest with the at least one sensor; retrieving data that is indicative of the at least one parameter of interest from the at least one sensor; loading the data into a computer system; and analyzing the data with the computer system to indicate trends in the wellbore.
[0007] According to a second aspect, the present invention consists of a method to screen wellbores in order to determine which wellbores should be subjected to a well test analysis tool, comprising: locating at least one sensor in the wellbore or in communication with fluids produced from the wellbore; obtaining data from the at least one sensor that is indicative of at least one parameter of interest; conducting a quick screening analysis of the data; and determining whether to subject the data to a well test analysis tool depending on the outcome of the conducting step.
[0008] According to a third aspect, the present invention consists of a system to retrieve and analyze data from a wellbore, comprising: at least one sensor located in the wellbore or in communication with fluids produced from the wellbore, the at least one sensor measuring at least one parameter of interest; a computer system adapted to retrieve data that is indicative of the at least one parameter of interest from the at least one sensor; and the computer system adapted to analyze the data to indicate trends in the wellbore.#
[0009] According to a fourth aspect, the present invention consists of a system to retrieve and analyze data from a wellbore, comprising: at least one central processing unit (CPU); at least one memory in communication with the CPU; the at least one CPU adapted to load data from a wellbore, the data indicative of at least one parameter of interest; and the at least one CPU adapted to analyze the data by using routines stored in the at least one memory in order to indicate trends in the wellbore.
[0010] According to a fifth aspect, the present invention consists of a method to screen wellbores in order to determine which wellbores should be subjected to a well test analysis tool, comprising: using a central processing unit (CPU) to load data, the data indicative of at least one parameter of interest in a wellbore; conducting a quick screening analysis of the data with the CPU; restricting the analysis with certain rules and assumptions to ensure the analysis is not a characterization tool; and determining whether to subject the data to a well test analysis tool depending on the outcome of the conducting step.
[0011] Advantages and other features of the invention will become apparent from the following description, drawing and claims.
BRIEF DESCRIPTION OF THE DRAWING
[0012] FIG. 1 is a well schematic including the sensors and computer system of the invention and overall system.
[0013] FIG. 2 is a schematic of the method performed by the overall system.
[0014] FIG. 3 is a more detailed illustration of the load raw data step of the method of FIG. 2 .
[0015] FIG. 4 is a more detailed illustration of the validate data step of the method of FIG. 2 .
[0016] FIG. 5 is a more detailed illustration of the condition data step of the method of FIG. 2 .
[0017] FIG. 6 a more detailed illustration of the perform analysis step of the method of FIG. 2 .
[0018] FIG. 7 is a more detailed illustration of the isolated events step shown in FIG. 6 .
[0019] FIG. 8 is a more detailed illustration of the long-term trend step shown in FIG. 6 .
[0020] FIG. 9 is a more detailed illustration of the screening analysis step shown in FIG. 7 .
[0021] FIG. 10 is a more detailed illustration of the build up and drawdown steps shown in FIG. 9 .
[0022] FIG. 11 is a more detailed illustration of the steady-state analysis step shown in FIG. 9 .
[0023] FIG. 12 is a more detailed illustration of the select type of analysis step shown in FIG. 2 .
[0024] FIG. 13 illustrates, in block form, a computer system.
[0025] FIG. 14 illustrates, in block form, a computer network/computer system.
DETAILED DESCRIPTION
[0026] FIG. 1 shows a typical hydrocarbon wellbore 10 that extends from the ground surface 12 . Wellbore 10 intersects a hydrocarbon formation 14 . A tubular string 16 is typically deployed within the wellbore 10 . The string 16 also normally carries various completion equipment, such as a packer 18 and a flow control valve 20 (to name a few). Hydrocarbons from the formation 14 flow into the wellbore 10 , into the tubing string 16 (such as through flow control valve 20 ), and then to the surface. In an alternative embodiment, the hydrocarbons are diverted into the annulus 22 of the wellbore 10 above the packer 18 and flow to the surface therein. In another alternative embodiment, a downhole pump (not shown) may be used to assist in conveying the hydrocarbons to the surface. In yet another embodiment, the wellbore 10 is an injection well in which fluids are injected from the tubing 16 into the formation 14 .
[0027] Tubing string 16 may be production tubing, coiled tubing, or drill pipe (to name a few). Wellbore 10 can be a land-based or a subsea well.
[0028] Sensors are deployed at various locations 24 in the wellbore 10 and production process in order to obtain relevant data regarding the wellbore 10 , formation 14 , and hydrocarbons. Sensors 26 may be deployed on the surface in communication with the pipeline that receives the hydrocarbons flowing from the wellbore 10 . Sensors 28 may be deployed in the annulus 22 above the packer 18 . Sensors 30 may be deployed within the tubing string 16 . And, sensors 32 may be deployed in the annulus 22 below the packer 18 . In another embodiment (not shown), sensors are deployed behind the casing of the wellbore 10 . Each sensor 26 , 28 , 30 , 32 may comprise a flow rate sensor (single or multi-phase), a temperature sensor, a distributed temperature sensor, a pressure sensor, an acoustic energy sensor, an electric current sensor, a magnetic field sensor, an electric field sensor, a chemical property sensor, or a fluid sampling sensor. Accordingly, each sensor 26 - 32 may obtain flow data, temperature data, pressure data, acoustic data, current data, magnetic data, electric data, chemical data, or fluid data (among others). In addition, each sensor location 24 may include more than one type of sensor or each sensor may sense more than one type of data. Each sensor 26 - 32 obtains its relevant data either continuously or at different time intervals, depending on the type of sensor, power parameters, and requirements of the operator. Each sensor 26 - 32 may also be an electrical or a fiber optic sensor, among others. The data from the sensors 26 - 32 is transmitted to a computer system 36 on the surface 12 .
[0029] There are different ways to transmit the data to the surface 12 . For instance, a data line 34 may connect each sensor 26 - 32 to the computer system 36 . The data line may 34 be an electrical, high capacity data transmission line, or it may be a fiber optic line. In one embodiment, each sensor 26 - 32 is connected to an independent data line 34 . In another embodiment, each sensor 26 - 32 is connected to the same data line 34 . Data from the sensors 26 - 32 may also be transmitted to the surface 12 by way of acoustic, pressure pulse, or electromagnetic telemetry, as these telemetry alternatives are known in the field.
[0030] Computer system 36 may be a portable computer, as shown in FIG. 1 , that can be removably attached from the sensors 26 - 32 . In this embodiment, a data storage unit 38 , which receives data from the sensors 26 - 32 , may be directly attached to the data lines 34 , and the portable computer system 36 is then removably attached to the data storage unit 38 . With the use of a portable computer system 36 , a user may provide a diagnosis and analysis of various wellbores while using a single computer system. Computer system 36 may be a personal computer or other computer.
[0031] In other embodiments, the data from sensors 26 - 32 is transmitted, either on a continuous or a time lapse basis, to a remote location such as the offices of the user. Remote transmission can be performed, for instance, by transmitting the data to a satellite which relays it onto the remote location, transmitting the data through a communication cable to the remote location, or transmitting the data through the internet to a web based location which can be accessed by the user perhaps on a password protected basis. These types of transmission enable the real-time monitoring of the data and wellbore, and also allow a user to take immediate corrective action based on the data received or analysis performed.
[0032] FIG. 13 illustrates in block diagram form an embodiment of hardware that may be used as the computer system 36 and to operate the representative embodiment of the present invention. The computer system 36 comprises a central processing unit (“CPU”) 210 coupled to a memory 212 , an input device 214 (i.e., a user interface unit), and an output device 216 (i.e., a visual interface unit). The input device 214 may be a keyboard, mouse, voice recognition unit, or any other device capable of receiving instructions. It is through the input device 214 that the user may make a selection or request as stipulated herein. The output device 216 may be a device that is capable of displaying or presenting data and/or diagrams to a user, such as a monitor. The memory 212 may be a primary memory, such as RAM, a secondary memory, such as a disk drive, a combination of those, as well as other types of memory. Note that the present invention may be implemented in a computer network 220 , using the Internet, or other methods of interconnecting computers. An example of a network of computers 222 is shown in block diagram form in FIG. 14 . Therefore, the memory 212 may be an independent memory 212 accessed by the network, or a memory 212 associated with on or more of the computers. Likewise, the input device 214 and output device 216 may be associated with any one or more of the computers of the network. Similarly, the system may utilize the capabilities of any one or more of the computers and a central network controller 224 . Therefore, a reference to the components of the system herein may utilize any of the individual components in a network of devices. Any other type of computer system may be used. Therefore, when reference is made to “the CPU,” “the memory,” “the input device,” and “the output device,” the relevant device could be any one in the system of computers or network.
[0033] With the data obtained from the sensors 26 - 32 , computer system 36 may perform the general method 100 of the present invention as schematically illustrated in FIG. 2 . The general method 100 (and its steps) may be embedded as software routines in memory 212 with the CPU 210 performing the required operations based on the data in the memory 212 . Alternatively, the general method 100 may be embedded as hardware logic circuits.
[0034] In the first step 110 of the general method 100 , computer system 36 , at the user's request, loads the raw data from the sensors 26 - 32 , either directly from the data lines 34 or from the data storage unit 38 , to the memory 212 . In the second step 112 , the raw data is validated by the computer system 36 . In the third step 113 , a user selects the type of analysis that is to be performed on the data. In the fourth step 116 , the raw data is then conditioned by the computer system 36 . In the fifth step 118 , an analysis, as selected by the user, is performed by the computer system 36 on the relevant conditioned data. In the sixth step 120 , an output of the selected analysis is provided to the user.
[0035] The load raw data step 110 is shown in FIG. 3 in more detail. In the load raw data step 110 , at the user's request, the CPU 210 loads the data collected from the sensors 26 - 32 into the memory 212 of the computer system 36 and may then also perform some preliminary work on the data. A project or file is first created by the CPU 210 at step 150 as requested by the user. Next, the CPU 210 loads the raw data onto the computer system 36 in step 152 and saves the data in memory 212 . Depending on the sensors 26 - 32 and accompanying software used for the sensors, the raw data for specific sensors may already be in certain formats, such as Unitest CD
[0036] (ASCII format), Excel Spreadsheet, Data Historian (including P 1 and IP 21 ), and relational databases (such as Oracle). In step 152 , computer system 36 is able to load the data from the sensors 26 - 32 in any format that is presented to the computer system 36 . Also in step 152 , if necessary, a user is able to select the channels (in the case of Data Historian formats) and columns (in the case of Excel Spreadsheet) that should be used by the computer system 36 in later steps for each data stream obtained from a sensor. If the user wishes, the raw data (or parts thereof) may be plotted versus time or versus other parameters in step 156 by the CPU 210 . Output plots may be printed or visually displayed by the user on the output device 216 .
[0037] Typically, the data representative of one physical parameter measured by a sensor is loaded into one “channel” in the memory 212 . The data of that channel can then be manipulated and plotted by the user via the CPU 210 at any point in time. Manipulation may include performing statistical analysis, including min-max, average, and standardization.
[0038] In one embodiment, the user will only have to select the appropriate channels and columns once for a given data source. The CPU 210 then stores a template in memory 212 for loading data from the relevant data source based on the original choices made by the user. The template is then made available by the CPU 210 to the user to load the next batch of data arriving from the same data source.
[0039] It is noted that in performing the load raw data step 110 , a user may choose to load the data obtained during specific time periods. For instance, a user may choose to load the data obtained for the past year, or only for one month. Or, of course, a user may choose to load the data obtained during the entire life of the well. Furthermore, the newly loaded data may be appended to previously loaded data to provide a specifically required or comprehensive set of data for the well.
[0040] The validate data step 112 is shown in FIG. 4 in more detail. In the validate data step 112 , the data is generally transformed into a cleaner set of data using various techniques. In step 200 , the relevant data from each of the sensors 26 - 32 is synchronized with respect to timing differences (such as clock difference, starting time difference, or known wrongly entered time).
[0041] It is noted that each data sample should have an associated time stamp. In step 202 , the data is then synchronized with respect to units so that data points from the same type of sensors are standardized to the same unit. In this step, units are also assigned to data that is missing units or whose units are not obvious. In step 204 , overlap resolution is next performed on data, if there are data streams for the same type of data (downhole pressure, for example) from different sources in time with a period or periods of overlap. If the user wishes, the validated data may be plotted versus time or versus other parameters in step 206 by the CPU 210 . Output plots may be printed or visually displayed by the user on the output device 216 . Steps 200 - 206 may be performed manually by the user or automatically by the CPU 210 through an appropriate subroutine stored in memory 212 . Moreover, the data may be saved by the CPU 210 on the memory 212 after each step 200 - 206 .
[0042] The select type of analysis step 113 is shown in FIG. 12 in more detail. By use of the input device 214 , a user may select to perform two types of analysis on the data: a long-term trend 115 and an isolated event 117 . The user may elect to conduct one or both of the analysis types. In the long-term trend analysis 115 , the data is analyzed to determine any long-term trends of the wellbore 10 and formation 14 . Diagnostic plots may be generated based on simple mathematical transformations of the measured data, such as plots of cumulative rate versus time, ratio of gas to oil production rates versus time, and productivity index. In the isolated event analysis 117 , data from specific events during the life of a well, such as build-ups, drawn-downs, or shut-ins, is isolated and analyzed to determine parameters of interest. Key reservoir and well parameters (such as skin, near-wellbore damage, permeability-thickness product, or other specific measures of well and reservoir performance) are determined or estimated using different well test analysis techniques.
[0043] The condition data step 116 is shown in FIG. 5 in more detail. In the condition data step 116 , the data is conditioned to enable a better analysis. In step 250 , a user may confirm or change the sampling rate used in the remainder of the analysis for each of the data sets. Data frequency may be reduced by a variety of methods, such as selecting the n th value of the data or using a moving average of the data. It is noted that different parts of the same data set (from one sensor) may have different sampling rates in order to focus or not on specific time periods. In addition, data sets from different sensors may also have different sampling rates. The data is next filtered in step 252 in order to provide a “clean” version of the data for further analysis. Various filtering techniques may be used, including means and median filtering. Filtering removes outliers and “noise” from the data And, in step 254 , a user may input any missing data points via the input device 214 . The missing data points may be inputted manually by the user, or the user may elect to allow the CPU 210 to interpolate or extrapolate any missing data points such as by the use of linear, cubic spline, or exponential interpolation and extrapolation methods or by using the data from another channel. If the user wishes, the conditioned data may be plotted versus time or versus other parameters in step 256 by the CPU 210 . Output plots may be printed or visually displayed by the user on the output device 216 . Steps 250 - 256 may be performed manually by the user or automatically by the CPU 210 through an appropriate subroutine stored in memory 212 . Moreover, the data may be saved by the CPU 210 on the memory 212 after each step 250 - 256 .
[0044] The type or types of conditioning performed on data (under condition data step 116 ) depend on the type or types of analysis to be performed on the data in perform analysis step 118 . For instance, the isolated event analysis 302 will normally require a higher data frequency than the long-term trend analysis 300 , therefore changing the sampling rate used (step 250 ) may not be performed for the isolated event analysis 302 . Alternatively, inputting missing data points (step 254 ) may need to be used for the isolated event analysis 302 but not for the long-term trend analysis 300 .
[0045] In the perform analysis step 118 as shown in FIG. 6 , the types of analysis chosen by the user, long-term trend 300 and/or isolated events 302 , are performed as discussed below.
[0046] The long-term trend analysis 300 is further illustrated in FIG. 8 . In step 350 , a user may select the plots or trends he/she wishes the CPU 210 to generate. Many different plots may be developed by the CPU 210 using the data obtained from the sensors 26 - 32 and the routines stored in memory 212 . For instance, the data obtained from the sensors 26 - 32 (such as surface pressure, downhole pressure, temperature, total flow rate, oil flow rate, water flow rate, and gas flow rate) may be directly plotted against time. Or, additional parameters, as will be discussed in relation to step 354 , may be calculated using the data obtained from the sensors 26 - 32 . Next, in step 352 , a user selects the time period for which he/she wishes to develop the plot. In step 354 , any parameters that must be calculated based on the user's selections in step 350 are calculated.
[0047] Examples of these parameters and known equations used to derive such parameters are:
[0000]
P
I
(
productivity
index
)
=
q
o
p
_
r
-
p
wf
,
[0000] where q o is the oil flow rate, p r is the reservoir i
pressure, and p wf is the pressure while flowing;
[0000]
G
O
R
(
gas
-
oil
ratio
)
=
q
g
q
o
,
[0000] where q g is the gas flow rate and q o is the oil flow rate; and
[0000]
W
O
R
(
water
-
oil
ratio
)
=
q
w
q
o
,
[0000] where q w is the water flow rate and q o is the oil flow rate.
Other parameters may of course be selected, such as wellhead pressure, pressure drop from the bottomhole to the wellhead, pressure drop between the reservoir and the completion, the ratio of the pressure drop between the reservoir and the completion and the oil flow rate, the gas flow rate, the liquid phase flow rate, and the water flow rate. In one embodiment, the user is offered the choice by the CPU 210 to select the parameters to be calculated from a list of parameters stored in memory 212 . In another embodiment, the user may define the parameter to be calculated (and then plotted in step 356 ) by manipulating the listed parameters and/or data. Manipulation can include any mathematical operation. For instance, if one data stream is flow at point A and another data stream is flow at point B, then a user may define a new parameter to be plotted which can be the difference between the flows at points A and B. In step 356 , the relevant plots are then developed by the CPU 210 and illustrated for the user on the output device 216 . The user can then analyze these long-term plots and observe any long-term trends of the reservoir 14 and wellbore 10 .
[0049] The isolated event analysis 302 is further illustrated in FIG. 7 . For isolated event analysis 302 , a user has a choice via the input device 214 to select either a quick screening analysis 320 or a robust analysis 322 . The robust analysis 322 itself is not the subject of this invention, although it is incorporated into the overall method 100 and system. There are currently various software packages available in the market that provide the robust theoretical analysis necessary to determine the relevant parameters and to characterize the wellbore or reservoir. These software packages include Schlumberger's Welltest 2000 and Procade. If a user selects the robust analysis 322 option, the CPU 210 exports the data from the sensors 26 - 32 to the relevant robust analysis programs (which programs may also be stored in memory 212 and driven by the CPU 210 ). The screening analysis 320 is meant to be a screening tool rather than a wellbore or reservoir characterization tool. The screening analysis 320 provides a user a quick way to screen or select which wellbores or reservoirs the user should subject to the much more time-consuming robust analysis 322 .
[0050] In order to ensure that the screening analysis 320 is a screening tool and not a more time-consuming characterization tool, certain assumptions and rules may be made in conducting the screening analysis 320 . These rules and assumptions may be stored in memory 212 or may be inputted or modified by the user via the input device 214 . First, a simple reservoir and wellbore model is assumed and no attempt is made to identify the “true” standard well test model. As is known, each standard model will produce a characteristic “signature” response on plots. Not identifying the true standard model compromises the quality of the model parameters, but since this is a screening and not a characterization tool, this is not a major concern. Also, in order to effectively analyze a build up or a drawdown period, such build up or drawdown period should be preceded by a stable rate period. Since the data from the sensors 26 - 32 is not from a planned well test, it must therefore be ensured that there is a reasonably stable rate period prior to any build up or drawdown period to be analyzed. In this regard, rate superposition for changing rates may be performed in order to generate an “equivalent” stabilized rate. In addition, characterization tools are typically based on single-phase flow; however, the data from sensors 26 - 32 may and likely will include multiphase data. For the screening analysis 320 , a single-phase analysis is performed on the multiphase data to solve for the effective permeability to the particular phase being considered (and not the absolute permeability one would obtain using single phase data). Moreover, with respect to skin calculations, the same single phase equations can be used to calculate a total skin (including due to multiphase flow).
[0051] The screening analysis 320 is further illustrated in FIG. 9 and is driven by the CPU 210 . A user can select three types of screening analysis via the input device 214 : a build up analysis ( 400 ), a drawdown analysis ( 402 ), or a steady-state analysis ( 404 ). As is known in the art, a “build up” typically refers to when the well is shut-in or closed and the bottomhole pressure is allowed to build up within the wellbore. A “drawdown” refers to when the well is then opened releasing the built up pressure in the wellbore. A “steady state” refers to when the wellbore and reservoir are operating and producing without substantial change. Once the user selects the desired type of analysis, the user is then (in step 406 ) prompted to select the time period for which he/she would like the analysis performed. In one embodiment, the computer system 36 automatically selects the relevant time periods that are relevant for each type of analysis and presents them to the user. For this computer-guided embodiment, a user may define the sensitivity or features that guide the CPU 210 in its automatic selection of the relevant time periods. This computer-guided embodiment is specially useful when the data is representative of a long time period. Next, in step 408 , the user is prompted to enter any variables that are required, in addition to the data obtained from the sensors 26 - 32 , to conduct the chosen analysis. Relevant variables may include a fluid model and property (such as a fully compositional PVTi), a well description (such as pressure drop from completion to gauge), basic reservoir properties (such as porosity), total compressibility, reservoir geometry (such as thickness), initial reservoir pressure, fluid viscosities, and borehole radius. In another embodiment, these variables are automatically incorporated from other programs or saved memory 212 accessible to the computer system 36 .
[0052] FIG. 10 illustrates the additional steps for the build-up analysis ( 400 ) and the drawdown analysis ( 402 ) steps. In step 450 , the log-log and semi-log plots are developed by the CPU 210 . These plots, which are known in the prior art and are stored in memory 212 , typically plot some function of pressure versus some function of time. For example, in semi-log build-up Horner analysis, a plot is made by the CPU 210 of bottomhole pressure versus the log of Horner time
[0000]
(
t
p
+
Δ
t
Δ
t
,
[0000] where t p is the producing time prior to shut-in and Δt is the shut-in time). Next, in step 452 , the CPU 210 fits a straight line along the relevant portion of the semi-log and log-log plots to represent the transient of interest. It is noted that in one embodiment type curve matching, which is normally used by true characterization tools to attempt the identification of the reservoir and wellbore model, is not used in the screening analysis 322 . And, in step 454 , using the relevant data from the sensors 26 - 32 , the variables entered in step 408 , the straight line developed in step 452 , and relevant equations known in the prior art and stored in memory 212 , the relevant reservoir and wellbore variables, including permeability (k), extrapolated pressure (p*), pressure at 1 hour (p 1hr ), productivity index (PI), and skin (s), are computed by the CPU 210 from the slope of the straight line.
[0053] FIG. 11 illustrates the additional step for the steady-state analysis 404 . In this step 456 , the relevant reservoir and wellbore variables (and specially the productivity index) are computed by the CPU 210 using the relevant data from the sensors 26 - 32 , the variables entered in step 408 , and relevant equations known in the prior art and stored in memory 212 .
[0054] Turning back to FIG. 2 , the output step 120 is conducted after the perform analysis step 118 . In the output step 120 , the CPU 210 displays relevant parameters computed in steps 454 and 456 to the user, and a standardized report with the relevant data, variables, computations, and plots may be printed out by the user via the output device 216 . The report may include the calculations and determinations from any characterization tool used in robust analysis step 322 , if applicable. Such output may be saved by the user in the memory 212 for use at a later date. Moreover, the data obtained from the sensors 26 - 32 , the shift during any alignment conducted in synchronization step 200 , the conditioned data resulting from condition data step 116 , and the variables entered in step 408 may be saved by the user in the memory 212 for use at a later date.
[0055] As shown by line 122 in FIG. 2 , a user may also at any time perform a different analysis on the same data set. Or, as shown by dotted line 124 , the user may restart the process with a new data set.
[0056] Any plots developed by the computer system 36 may be saved in various file formats, such as jpeg, bmp, and gif on memory 212 . Further, any plots developed by the computer system 36 may be exported by the CPU 210 to other software programs, such as Microsoft PowerPoint and Word.
[0057] The user may then review and analyze the report and any plots produced during the method 100 to determine whether any action should be taken for the relevant wellbore or reservoir. In an alternative embodiment, computer system 36 may automatically advise the user, such as by an alarm or indicator, that certain wellbore or reservoir parameters are out of pre-determined expected ranges and that corrective action is therefore recommended. By way of example, corrective action can involve closing or opening a flow control valve, injecting a fluid into the well, perforating another portion of the wellbore, stimulating the formation, or actuating devices in the wellbore (such as a packer, perforating gun, etc.). Some of the corrective actions could also be automatically performed by the computer system 36 in that the computer system 36 can send the relevant commands to the appropriate devices in the wellbore by way of known telemetry techniques (such as pressure pulse, acoustic, electromagnetic, fiber optic, or electric cable).
[0058] As previously described, instructions of the various routines discussed herein (such as the method 10 performed by the computer system 36 and subparts thereof including equations and plots) may comprise software routines that are stored on memory 212 and loaded for execution on the CPU 210 . Data and instructions (relating to the various routines and inputted data) are stored in the memory 212 . The memory 212 may include semiconductor memory devices such as dynamic or static random access memories (DRAMs or SRAMs), erasable and programmable read-only memories (EPROMs), electrically erasable and programmable read-only memories (EEPROMs) and flash memories; magnetic disks such as fixed, floppy and removable disks; other magnetic media including tape; and optical media such as compact disks (CDs) or digital video disks (DVDs).
[0059] While the invention has been disclosed with respect to a limited number of embodiments, those skilled in the art, having the benefit of this disclosure, will appreciate numerous modifications and variations therefrom. It is intended that the appended claims cover all such modifications and variations as fall within the true spirit and scope of the invention. | A system and method including a sensors deployed in a wellbore, the sensors measuring various downhole parameters. The system retrieves the relevant data from the sensors, validates the data, conditions the data, and analyzes the data to diagnose the wellbore and the reservoir to indicate trends therein. The system has the capability of enabling the characterization of the wellbore and reservoir by being linked to well test analysis tools. The system also has a screening analysis that is much less time consuming than well test analysis tools and that indicates to a user which wellbore and/or reservoirs should be subjected to the more robust and time consuming well test analysis tool. | 4 |
FIELD OF THE INVENTION
The present invention relates to thermotropic di-s-triazinic derivatives.
BACKGROUND OF THE INVENTION
The chemistry of triazines is a very widely investigated field, because the triazinic derivatives are considerably interesting products. They are widely described in the technical literature because they have many uses, such as, in the agrochemical sector as herbicides, in the field of polymers as additives (for flame-proofing, light-stabilizer purposes, etc.), as monomers for thermoplastic polymers and thermosetting resins, in the field of dyes (reactive dyes for cellulosic fibers), and so forth.
In European patent application No. 53,775, for example, light stabilizers for polyolefins, or for acrylic polymers are disclosed. These are obtained by polycondensation of a diamine with a di-s-triazinic derivative.
This latter product is constituted by two triazinic rings bonded by a diamine and substituted in their 2-position with a halogen and in their 4-position with a group selected from a halogen, or from phenyl, alkoxy, aminic, and so forth radicals.
The present applicant has found now that di-s-triazinic derivatives containing two triazinic rings substituted in their 2- or 4-positions with particular alkoxy groups are optically anisotropic in the molten state, and have liquid crystalline properties.
It is known that the compounds endowed with such properties have in the molten state, and within a well-defined temperature range, an ordered arrangement of molecules. This gives to liquid phase an isotropic properties, which is very interesting.
All the preceding references are hereby incorporated by reference.
SUMMARY OF THE INVENTION
Therefore, an object of the present invention is thermotropic di-s-triazinic derivatives comprising the general formula: ##STR2## wherein:
m is zero or an integer of from 1 to 5,
n is an integer of from 5 to 30, preferably of from 5 to 12, and
X is a halogen, such as chlorine or a CH 3 (CH 2 ) m O-- group.
DETAILED DESCRIPTION OF THE INVENTION
The di-s-triazinic derivatives of the present invention have never been before described in technical literature as compounds having liquid-crystalline properties in the molten state. These products in fact originate an anisotropic molten phase, viz., a mesophase, and have melting temperatures within the range of 50° to 250° C.
The liquid-crystalline organization can be evidenced by means of analyses on Differential Scanning Calorimeter (DSC), analyses on optical microscope under polarized light, and X-ray diffraction.
The thermotropic, or liquid-crystalline, behavior of the di-s-triazinic derivatives of the present invention is not foreseeable on the basis of the teaching of the prior art. See "Electro Optic-Principles and Applications", vol. 38, page 23 (1973); "Applications of Liquid Crystals", Meier (1975).
In fact, the compounds of the present application do not involve any structures of rigid or discoidal shape, or any of the other structure types which are generally assumed as necessary for constituting a mesophase of thermotropic type.
The products having the general formula (I) can be obtained by reacting 2,4-dichloro-6-alkoxy-1,3,5-triazine with an alkylidene-diamine according to the reaction scheme: ##STR3##
2,4-dichloro-6-alkoxy-1,3,5-triazine can be obtained by known process, and, in particular, according to the process as disclosed in Journal of American Chemical Society 73, 2986 1951), hereby incorporated by reference.
The reaction is carried out under atmospheric pressure at temperatures within the range of 40° to 100° C. The reaction is preferably, in a solvent having a boiling temperature compatible with the reaction temperature, and having a good solvating power for both the reactants and the products.
Suitable solvents are the polar, aprotic solvents as tetrahydrofuran, dioxane, acetone, methylethylketone, and so forth.
The hydrogen chloride which is formed is neutralized using an organic base in solution or using an inorganic base in suspension. Such bases can be tertiary amines, lutidines, or akali metal hydroxydes, alkali-metal carbonates or bicarbonates wherein the alkali-metal may be sodium, potassium, and so forth.
The reaction product can be recovered from the solution using known methods, such as, by evaporating the solvent, or by precpitating it using a non-solvent, and subsequent filtration to obtain a microcrystalline powder.
Illustrative examples of substituted triazines having the general formula (II), which can be used in the synthesis of the di-s-triazinic derivatives of the present invention, are: 2,4-dichloro-6-methoxy-1,3,5-triazine, 2,4-dichloro-6-ethoxy-1,2,5-triazine, 2,4-dichloro-6-n-propoxy-1,3,5-triazine, and so forth.
Any diamines having the general formula (III) can be used in the synthesis of the di-s-triazines of the present invention. Illustrative examples are: 1,6-diamino-hexane, 1,8-diamino-octane, 1,10-diamino-decane, 1,12-diamino-dodecane, and so forth.
The thermotropic di-s-triazinic derivatives of the present invention can be used as components for optical memory devices. The crystal-liquid crystal and the liquid crystalisotropic melt transistions, even of thermodynamically reversible, can be cinetically controlled by thermal freezing.
This permits the cohexistance and the stability of such phases at room temperature. It is, therefore, possible to easily obtain a thin film with the compound, object of the present invention, in its mesomorphic state and to generate in it, by local heating with a laser beaam isotropic-transparent microzones which are still stable at room temperature. Other uses are as component for opto-electronic displays, as components for nonlinear optics, as additives for thermoplastic polymers, and so forth.
EXAMPLES
For the purpose of better understanding the present invention and to better practicing it, some illustrative nonlimitative examples are reported.
EXAMPLE 1
The preparation is disclosed of N,N'-bis[2-chloro-4-methoxy-1,3,5-triazinyl]-hexamethylene-diamine having the formula: ##STR4##
To a flask of 250 ml oaf capacity are charged, 18 g of 2,4-dichloro-6-methoxy-1,3,5-triazine, 6 g of anhydrous sodium carbonate and 80 ml of dioxane. To a dropping funnel are charged, 5.8 g of hexamethylenediamine, 60 ml of dioxane, 20 ml of distilled water.
The diamine-containing solution is added dropwise to the triazine-containing solution. This latter solution is stirred at room temperature. The reaction is continued, always with stirring, at 80° C. for 2 hours.
The solution is then poured into 400 ml of distilled water.
A precipitate is formed which is filtered off, washed with distilled water, and vacuum dried at 60° C.
The product is recrystallized from chloroform.
In this way, after drying at 60° C. under vacuum, 11.22 g (yield: 68%) of product in the form of a white microcrystalline powder is obtained.
The product is identified:
Elemental analysis:
Theoretical: C %: 41.70; H %: 4.96; N %: 27.80; Cl %: 17.60 Found : C %: 41.98; H %: 4.62; N %: 27.88; Cl %: 17.40
Mass Soectrophotometry: M + : 402; 229 187; 173.
The purity of the product is determined by HPLC (High Performance Liquid Chromatrography), and is higher than 95%.
Observations on optical microscope under polarized light evidences the formation of an anisotropic mesophase within the temperature range of from 146° to 150° C.
EXAMPLE 2
The preparation is disclosed of N,N'-bis[2-chloro-4-methoxy-1,3,5-triazinyl]-1,10-diamino-decane having the formula: ##STR5##
The process is carried out according to the same modalities as in Example 1. However, hexamethylenediamine is replaced by 8.6 g of 1,10-diamino-decane.
After crystallization in chloroform, 14.7 g (yield: 64%) of product in the form of a white microcrystalline powder is obtained.
The product is identified:
Elemental analysis:
Theoretical: C %: 47.07; H %: 6.10; N % : 24.41; Cl %: 15.45 Found: C % :47.39; H %: 6.62; N %: 24.30; Cl %: 14.98
Mass Spectrophotometry: M + ; 458; 386; 285; 229; 187; 173.
The purity of the product is determined by HPLC, and is higher than 98%.
Observations on optical microscope under polarized light evidences the formation of an anisotropic mesophase within the temperature range of from 112° to 140° C.
EXAMPLES 3-6
By operating with the same modalities as disclosed in Example 1, compounds of general formula (I) are prepared by starting from 2,4-dichloro-6-methoxy-1,3,5-triazine, and from diamines respectively having 7, 8, 9 and 12 carbon atoms.
For such compounds, the following temperature ranges of existence of mesophase (as determined on microscope under polarized light) are observed:
______________________________________No. of Diamine Temperature Range of Meso-Carbon Atoms phase Existence (°C.)______________________________________7 132-1368 113-1169 91-10012 81-91______________________________________
EXAMPLE 7
The preparation is disclosed of N,N'-bis[2-chloro-4-methoxy-1,3,5-triazinyl]-1,12-diamino-dodecane having the formula: ##STR6##
To a flask of 250 ml of capacity are charged, 10 g of diamino-dodecane, 6 g of anhydrous sodium carbonate and 80 ml of dioxane.
To a dropping funnel are charged, 20.8 g of 2,4-dichloro-6ethoxy-1,3,5-triazine and 50 ml of dioxane.
The triazine-containing solution is slowly added dropwise to the diamine-containing solution. This latter solution is kept stirred at room temperature. The reaction is continued, always with stirring, at 50° C. for 1 hour. The solution is then poured into 400 ml of distilled water.
A precipitate is formed which is filtered off, washed with distilled water, dissolved in chloroform, dried with potassium carbonate, filtered, evaporated under vacuum, recrystallized in hexane.
After drying this recrystallized precipitate at 60° C. under vacuum, 14.9 g (yield: 58%) of product in the form of a white microcrystalline powder is obtained. The product is analyzed by:
Elemental analysis:
Theoretical: C %: 51.27; H %: 6.99; N %: 21.75; Cl %: 13.77 Found : C %: 51.11; H %: 7.33; N %: 21.56; Cl %: 13.47
Mass Spectrophotometrv: M + : 514; 187; 173.
The observations on optical microscope under polarized light evidence the formation of an anisotropic mesophase within the temperature range o from 79° to 99° C.
Although the invention has been described in conjunction with specific embodiment, it is evident that many alternatives and variations will be apparent to those skilled in the art in light of the foregoing description. Accordingly, the invention is intended to embrace all of the alternatives and variations that fall within the spirit and scope of the appended claims. | Thermotropic di-s-triazinic derivatives are taught having the general formula: ##STR1## wherein: m is zero or an integer of from 1 to 5,
n is an integer of from 5 to 30, and
X is a halogen, such as chlorine, or a CH 3 (CH 2 ) m O-- group. | 2 |
FIELD OF INVENTION
The invention relates to a method for absorbing sound in a clean-room environment and the apparatus, sound-absorbing panel, for carrying out that method; and more particularly relates to a sound-absorbing panel that is lightweight, washable and an effective sound absorber of acoustical energy in a selected range of frequencies.
BACKGROUND OF INVENTION
Noise generated in a clean-room environment, a room for use as for example in food processing, needs to be attenuated in order to allow for minimizing the background noise to at least within the limits specified by the Occupational Safety and Health Administration (OSHA). Numerous devices have been developed to effectively absorb sound, acoustical tile and other perforated sound absorbing material are examples. The problem of absorbing sound in a clean-room environment requires that the sound absorbing panel preferably have few areas in which organic growth can be supported and must be easily cleanable. While solutions to this problem have been found, U.S. Pat. No. 4,301,890 to Zalas is illustrative, such honeycomb diaphragm type panels are inherently expensive and still have the problem of puncture, since the membrane is simply stretched over the honeycomb area as a drumhead would be stretched over a drum body.
Heretofore, many different other methods have been utilized in an effort to make porous material suitable as sound absorber for clean-room, sanitary enrironments. These methods include inter alia the covering of traditional porous type acoustical ceiling tile with washable plastic surfaces. Of course these methods were unsuccessful since the acoustical attenuation features of the tile were seriously degraded by the coating process.
Therefore, there is a need for an inexpensive acoustical absorption panel suitable for clean-room environment in that it be washable and preferably hermetically sealed against the environment while still retaining full acoustical absorption characteristics within the specific acoustical frequency range to be absorbed.
SUMMARY OF THE INVENTION
I have developed a sound-absorbing panel for use in a clean-room environment which comprises a fiberglass core of specific thickness that is hermetically sealed within a continuous membrane, the membrane being preferably waterproof and substantially smooth to allow washing, the membrane being attached to at least one of the broad surfaces of the fiberglass core by means of an adhesive disposed in a continuous pattern of closed geometric figures, the places of attachment of the membrane to the fiberglass core defining the edges of said geometric figures. In this way, the membrane occupying the central portion of each of the geometric figures is free to act as a small independent diaphragm, the entire surface of the panel comprising a series of such independent diaphragms. Further, the size of the geometric figures is controlled in order that the resulting diaphragms will have lower order natural frequencies of vibration which correspond to the frequency range of the sound wave energy to be absorbed.
Another aspect of the present invention resides in the provision of a method for absorbing sound within a clean room environment comprising the steps of disposing on at least one interior surface of said clean room a sound absorbing panel, said panel having a fiberglass core of specific thickness, the core being hermetically sealed within a continuous membrane, the membrane being washable, non-porous, and substantially smooth to allow washability, the membrane being attached to at least one of the broad surfaces of the fiberglass core in a continuous pattern of closed, planar geometric figures, the places of attachment of the membrane to the fiberglass core defining the edges of said geometric figures. In this way, the membrane occupying the central portion of each of the geometric figures is free to act as a small, independent diaphragm, the entire surface of the panel comprising a series of such independent diaphragms. Further, the size of the geometric figures is controlled in order that the resulting diaphragms will have lower order natural frequencies of vibration which correspond to the frequency range on the sound wave energy to be absorbed. The sound absorbing panel is disposed in such a way on the interior surface of the room that the side having the continuous pattern of closed geometric figures faces the interior of the room.
An additional aspect of the present invention resides in modifying the sound-absorbing panel above described by the disposition of a perforated planar material between the membrane and the fiberglass core, the perforated material providing the site at which the membrane is attached, the perforated planar material in turn being attached preferably by means of an adhesive to the surface of the fiberglass core. The perforations in the perforated planar material correspond to the geometric figures sought to be produced and are specifically controlled in size for the above described reasons.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a prospective view of a sound-absorbing panel according to the present invention.
FIG. 2 is an enlarged corner detail plan view of the sound-absorbing panel of FIG. 1.
FIG. 3 is an elevational sectional view taken along line 3--3 of FIG. 2.
FIG. 4 is an enlarged corner detail plan view of an alternative embodiment of an acoustical panel according to the present invention.
FIG. 5 is an elevational sectional view along line 5--5 of FIG. 4.
FIG. 6 is a graph, the Random Incidence Absorption Coefficient versus Sound Wave Frequency, for a sound-absorbing panel according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
It was discovered by Zalas, U.S. Pat. No. 4,301,890, that a suitable sound-abosorbing panel could be fabricated by placing a membrane in contact with a honeycomb core material. The primary feature of that particular panel was that the sizing of the honeycomb compartments in conjunction with the material properties of the membrane, produced a flexible diaphragm at each honeycomb chamber in which the lower order natural frequencies of vibration of the diaphragm were substantially similar to both (1) the natural low order frequencies of vibration of the diaphragm in combination with the cavity in the honeycomb core and (2) the lower order standing wave frequency of sound in the cavity itself. In this way, the acoustical absorption properties of the panel were due to the hysteretic damping associated with the flexing of the membrane rather than simply the absorption of the sound in a fibrous material. Lower order frequencies of both the natural frequency and standing wave natural frequency type include the fundamental frequency and about the first ten harmonies of the fundamental frequency. Thus, the membrane, and more particularly, each of the individual diaphragms associated with the individual honeycomb chambers acted together as the primary sound-absorbing elements. The present invention provides a fibrous material core with a membrane stretched over that core, the membrane being attached to the core itself, or indirectly to the core via an intermediary perforated planar material, in such a way that only portions of the membrane are actually attached to the core, and those points of attachment define the edges of a continuous pattern of closed, planar geometric figures. The central portion of each of these geometric figures is not attached to the core or to any intermediate material and is free to act as an individual, independent diaphragm. The presence of the fibrous material, preferably a fiberglass core, immediately adjacent to each of the vibrating diaphragms does not interfere with the free vibration of the diaphragm, and therefore, it was discovered that by selectively attaching the membrane to the fiberglass core utilizing a purposefully sized geometric pattern, that properties similar to those derived from a membrane/honeycomb sound absorbing panel could be achieved in a much more inexpensive manner.
The sizing of the geometric figures, be they hexagons, circles, or other similar closed geometric figures, may be sized in order to "tune" the panel to selectively absorb sound waves in the range of acoustical or sound wave energy that is sought to be absorbed. The sizing of these geometric figures requires that the sound band to be absorbed or attenuated be known and also the fundamental properties of the membrane material must be well known. Additionally, it has been found that the thickness of the fiberglass core material plays a significant part in the overall effectiveness of the acoustical panel. In this way, the low order natural frequencies of the diaphragms in the membrane and the low order natural frequencies of the membrane/material thickness and also the low order standing wave natural frequencies of sound in that material thickness must be substantially similar, and lie within the sound wave energy range to be absorbed. The equations for computing these various frequencies are similar to those previously described by Zalas. The membrane natural frequency is given by:
f.sub.m =β(0.46a.sup.-2 t)(E/ρ(1-σ.sup.2)).sup.1/2 Hz.(1)
The combination of membrane/material thickness natural frequency is given by:
f.sub.c =60(Md).sup.-1/2 Hz. (2)
The material thickness standing wave natural frequency is given by:
f.sub.s ≃340/3d (3)
Where:
f m =the membrane natural frequency in Hertz;
t=membrane thickness in meters;
β=1.02, 1.47, 1.88, 2.01, . . . factors as determined for a circular plate of fixed perimeter
a=membrane radius in meters (the radius of a circle having an area equal to the cross-sectional area of a diaphragm within the membrane);
E=elastic modulus of the membrane in Newtons per square meter;
ρ=membrane density in kilograms per cubic meter;
σ=Poisson's ratio of membrane;
f e =combination membrane/material thickness natural frequency in Hertz;
M=equivalent surface mass of membrane in kilograms per square meter;
M=M.sub.1 M.sub.2 /(M.sub.1 +M.sub.2) (4)
M 1 ,M 2 =surface masses, respectively, of the two membranes in kilograms per square meter;
d=material thickness in meters (fiberglass core thickness); and
f s =frequency between first quarter wave and first half-wave standing wave resonance of sound in the material thickness in Hertz.
The figures are best understood by reference to FIGS. 1,2, and 3 which depict a perspective view of a sound-absorbing panel in accordance with the present invention details and sections of the same. A fibrous material 10, preferably fiberglass with a density of 3.5 to 4 lbs. per cubic foot (56 to 64 kilograms per cubic meter), is enclosed by the combination of membrane 12 on its upper extensive surface and a similar membrane 14 along its lower extensive surface, membranes 12 and 14 being sealed together by a seal 16 which is preferably hermetic sufficient to prevent the intrusion of air, water or foreign material into the fiberglass core area. It will be apprciated that membranes 12 and 14 may be a single, continuous membrane that is disposed to fully enclose the core. Enclose means to fully surround the core in a three-dimensional way. The membrane material is preferably 1.5 to 2.0 mil (0.38 to 0.51 centimeter) thick polyurethane as for example, the material marketed by Norwood Industries under the name Korel (a registered trademark of Norwood Industries). The specified polyurethane material has an elastic modulus of 1×10 9 Newtons per square meter, a density of 1.24×10 3 killograms per cubic meter, and a Poisson's ratio of 0.4. Therefore, to estimate the size of the closed geometric figure to produce a diaphragm capable of absorbing wide sound wave energy range centering on 1000 Hz. to about 2000 Hz., the usual sound range audible to the human ear and often caused by equipment operating in food processing area, that diameter should be approximately 1/2 inch (12.7 mm.). The membrane 12 on the upper extensive surface of the fiberglass core is attached at the edges of the geometric figures to be formed preferably by means of an adhesive. Reference to FIG. 2 will show the attachment areas 20 and the open diaphragm areas 22. An adhesive may be applied either to the fiberglass surface as by means of a stencil or other such means or to the reverse side of the membrane 12 again in the appropriate pattern allowing for the closed diaphragms to be appropriately formed. FIG. 2 indicates the geometric shape as being closed independent hexagon shapes, while reference to FIG. 4 shows a circular pattern in which closed, independent circular shaped diaphragms 46 are formed while the intermediate area 44 is the attachment area.
Reference to FIGS. 4 and 5 together will describe an alternative embodiment of the sound-absorbing panel. A fiberglass core 30 is sealed within a membrane 32 across the upper extensive surface of said fiberglass core and a membrane 34 over the lower extensive surface of the fiberglass core, the two membranes 38 and 34 being sealed together at seal 36 to prevent the intrusion of air, water and dirt. A perforated planar material 38 has been inserted between membrane 32 and fiberglass core 30. The perforated planar material has been perforated in this case with circles the size of the desired diaphragms 46. The remaining material in the perforated planar material provides the surface areas for gluing at 44. An adhesive 40 has been applied to the upper surface of the perforated material 38 that it may adhere to the membrane 32 producing the diaphragms 46 while a similar adhesive 42 has been applied to the opposite face of perforated material 38 so that the perforated material may adhere to the upper extensive surface of the fiberglass core 30.
It will be appreciated that the membrane may be attached to both the upper extensive surface and to the lower extensive surface of the fiberglass core either by directly applying the membrane to the fiberglass core material as described in FIGS. 1-3 or by utilization of an intermediate perforated material as illustrated by FIGS. 4 and 5. The utilization of both sides of the fiberglass core material would allow for acoustical interception on either face of the sound absorbing panel. The presence of the membrane along the lower extensive surface, whether it be adhered in a geometric pattern, or loosely applied and maintained in position by means of the hermetic seal, provides a backup mass to the panel which is necessary in order to allow the fiberglass core to participate in the sound absorption by the panel. The primary sound absorbing element remains the diaphragms on the upper extensive surface of the panel.
Turning now to FIG. 6 which is a graph of the Random Incidence Absorption Coefficient, a quantification well known in the art, versus Sound Wave Frequency for a panel utilizing a continuous pattern of closed geometric figure diaphragms according to the present invention wherein the average diameter of the diaphragms measured either as the diaphragm of a circle or as the circular equivalent of a polygonal figure is approximately 1/2 inch (12.7 mm.). It can be seen that the graph centers on approximately 1000 Hz. to 2000 Hz., retaining relatively high absorption over a wide range of sound wave energy frequencies, (250 Hz. to 8000 Hz.). This confirms the results of the previous calculations.
It will be appreciated that the fibrous core material of such an acoustical panel need not be fiberglass but may be of other fibrous materials of various densities. Fiberglass was chosen to illustrate the various embodiments of this invention since it is readily available and relatively light weight for easy handleability. It will also be appreciated that various other membrane materials may be utilized provided they have the features of washability, nonporosity and being relatively smooth so as not to hide organic growth in a clean room environment. Additionally, it will be appreciated that other diaphragm diameters may be utilized depending upon the target range of sound energy sought to be absorbed, or attenuated.
It will be appreciated that numerous changes and modifications may be made in the above described embodiments of the invention without departing from the scope thereof. Accordingly, the foregoing description is to be construed in an illustrative and not in a limitative sense, the scope of the invention being defined solely by the appended claims. | A method of absorbing sound generated within a clean-room environment and the sound-absorbing panel for carrying out that method, wherein said sound absorbing panel comprises a fibrous core material enclosed in a non-porous membrane, said membrane being attached to at least one of the extensive surfaces of said fiberglass core in a series of closed geometric figures. The membrane occupying the central portion of each of said geometric figures defines a diaphragm, the dimensions of the diaphragm being configured such that the lower order natural frequencies of vibration of each of the independent diaphragms correspond substantially to the frequency range of sound to be absorbed. | 1 |
FIELD OF THE INVENTION
The present invention relates to a chip crushing device more particularly the present invention relates to surface designs for cooperating working surfaces adapted to squeeze wood chips there between and modify the structure of the chip to make it more uniformly receptive to impregnating chemicals.
BACKGROUND TO THE INVENTION
In the manufacture of pulp and paper wood is usually chipped into wood particles using a chipper. Many types of chippers available, however the conventional chipper cuts across the wood at an angle to the grain to define the length of the chip and the thickness is determined by splitting along the grain. Therefore, despite the fact that major investigations have been made on cutting angles of the knives etc., the thickness of the chips produced by such conventional chippers is not accurately controlled.
Wafer chippers have also been used to produce chips for pulping, such chippers or waferizers as they are sometimes called cut generally along (parallel to) and across the grain with the main cutting edge parallel to the grain to produce chips that have a uniform thickness and therefore a more uniform impregnation characteristic. However, the benefits derived from wafer chips can only be obtained if only wafer chips are used to charge the digester. However, since it is normal practice to purchase chips from a variety of different suppliers and not all suppliers have the same type of wafer chipper the uniformity in thickness obviously is not obtained and therefore neither would the benefits. Furthermore the wafer chipper is much more expensive to maintain since it generally requires the use of a plurality of discrete knives, each of which cuts a single chip.
It has been proposed to treat chips produced by a conventional chipper to render them more uniformly impregatable for example by shredding of conventional chips to reduce them to smaller particles which may be more quickly and more uniformly impregnated, however, such shredding generally increases the number of fines which cause problems during digestion that to a degree defeat the purpose of the shredding operation.
It is also proposed to crush chips using a chip crusher such as the crusher shown in Canadian patent No. 825,416 issued Oct. 29, 1969 to Kutchers et al which utilizes a pair of rolls to crush the chips and fissure them to render them more easily and more uniformly penetrable by cooking liquor in the pulping process.
In the said Kutchera et al patent a specific surface design is proposed wherein each of the rolls are provided with ribs spaced 0.375 to 0.91 inch and have uniform heights between about 0.007 and 0.13 inch, and surfaces or land areas of 0.12 inch to 0.2 inch with the rib height ratio of the two rolls never exceeding about 4 to 1.
The device of the Kutchera et al patent has been tried but it is believed it is no longer in operation, part of the problem being the limited capacity of the equipment.
U.S. Pat. No. 3,962,966 issued June 15, 1976 to Lapointe describes an improved arrangement for increasing the throughput through the crusher. In this device the chips are fed axially onto a rotating disc which flings them out radially in a substantially one chip thickness layer, that passes between a roll and a working surface of the disc to squeeze chips of greater than a certain thickness.
BRIEF DESCRIPTION OF THE INVENTION
It is an object of the present invention to provide a new surface design of the working surfaces of a crusher such as those shown in the said Canadian patent of Kutchera et al or in the Lapointe type crusher shown in U.S. Pat. No. 3,962,966.
Broadly the present invention relates to a chip crusher composed of a pair of co-operating surfaces defining a pressing nip, said surfaces being mounted to move in substantially the same direction through said nip, one of said surfaces being provided with a plurality of land areas separated by valleys, said land areas being substantially continuous and extending substantially in said direction of movement as said one surface passes through said nip, each of said land areas being between about 0.1 to 0.04 inch in width in the direction perpendicular to said direction of movement and being spaced centre to centre of said land areas by 0.2 to 0.6 inch said valley having a depth of at least 0.03 inch and having sloping side walls extending no greater than 160° and preferrably between 135° and 160° to said land areas, the other of said surfaces forming the periphery of a roll being provided with a plurality of teeth with the crown of each said looth defining a line preferably extending substantially perpendicular to said direction of movement through said nip and having a tooth depth of between about 0.05 inch and 0.1 inch and having their crowns spaced between about 0.1 and 0.6 inch.
BRIEF DESCRIPTION OF THE DRAWINGS
Further features, objects and advantages will be evident in 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 section through a plate or roll illustrating the surface configuration of one of the surfaces.
FIG. 2 is an end view of a roll incorporating the co-operating or mating surface.
FIG. 3 is a cross section of the preferred embodiment of a device employing the mating crushing surfaces of the present invention.
FIG. 4 is a plan view of the two discs used in the embodiment of FIG. 3.
FIG. 5 is an alternative embodiment incorporating the present invention in a chip crusher of the type described in the said Kutchera et al patent.
FIG. 6 is a plan view schematically illustrating the pressure pattern applied to a chip passing through a nip formed between a pair of surfaces incorporating the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The configurations of the two mating surfaces are depicted in FIGS. 1 and 2.
The surface 10 of FIG. 1 is composed of a plurality of spaced land areas designated at 12. Each being positioned in the same plane and having a width W and spaced from the adjacent land areas 12 by a distance centre to centre as indicated at S. The valleys 14 between each of the land areas 12 are formed by a pair of sloping sidewalls 16 and 18 extending between the surfaces or land areas 12 and the planer bottom sections 20 of the valleys. The sections 20 are substantially parallel to the areas 12. These sidewalls 16 and 18 extend at an angle θ to the sections 20 at the bottom of the valleys 14 and thus to the land areas 12. The sections 20 each have a width generally indicated at Z in FIG. 1.
The land areas 12 and thus the valley 14 there between extend generally in the direction of relative movement between the surface 10 and the co-operating surface 22 shown in FIG. 2. If the surface 10 is incorporated on the disc as shown in FIG. 4 the land areas 12 form concentric rings spaced by the valleys 14 or if the surface 10 is provided on a roll such as that indicated schematically in FIG. 5 the land areas 12 will extend circumferentially on the roll and form a plurality of spaced ring pressure members each on substantially the same radius extending circumferentially around the roll as right circular rings.
It has been found by experiment that the width of the land areas 12 as indicated by the letter W must be within certain limits as must the spacing S between the land areas 12 if proper fissuring of the chips is to be obtained. These dimensions may vary depending on the thickness and or length of the chip to be treated using the device however they will generally lie within the following ranges W=0.1 to 0.04 inch, S=0.2 to 0.6 inch and θ should never be less than about 20°, i.e. the angle between the land area and the side wall should not exceed 160°, it being important that the depth d i.e. the total depth of the valleys between the land areas 12 and the bottom surfaces 14 be at least 0.03 inch, obviously the dimension Z will depend on the angle θ spacing S and width W as well as the depth d for any given configuration. The spacing S should be such that the nominal chip length to be treated will substantially always contact at least two land areas.
The mating surface 22 adapted to cooperate with the surface 10 is provided on a roll such as the roll indicated at 24 in FIG. 2 since at least one of the surfaces 22 or 10 will be the surface of a roll to form a nip. The peripheral surface 22 of the roll 24 is formed by plurality of uniformly spaced teeth having their apex ends or crowns 26 extending in lines substantially longitudinal of the axis of rotation of the roll (see FIGS. 2 and 3). Each of these teeth has its crown 26 formed by the extention of a front face 28 and a trailing face 30 which form a saw tooth like configuration. These faces 28 and 30 preferably meet at 90° generally between about 60° and 120° and the faces 30 will preferably be at an angle α to a tangent to the surface of the roll 24. The angle α will be between about 5 and 45 degrees, preferably about 15°. The circumferencial spacing C between a pair of adjacent crowns 26 will generally be about equal about 0.1 to 0.6 inch so that 2 teeth will normally engage a chip and the depth of these teeth i.e. the height of the walls 28 as indicated by D will be at least 0.03 inch and generally will not exceed 0.1 inch.
The radius of the roll 24 i.e. of the crowns 26 of the teeth determines the angle of attack of the teeth to the chip thus when the roll diameter changes it may be desirable to modify the size and shape of the teeth. The diameter of the roll should be chosen to ensure the chips will be drawn into the nips by the action of the two surfaces 10 and 22. The diameter of the roll for use in a roll and disc combination as illustrated in FIGS. 3 and 4 should be between about 3 and 12 inches preferably between 5 and 8 inches. The height of gap or clearence G (see FIG. 5) of the nip for either the disc and roll combination or the pair of rolls embodiments will depend on the maximum tickness chip to be fed to the nip and the thickness of the treated chips or spacing between fissures in the treated chips. Generally the nips will have gaps G of 0.04 to 0.1 inch. In one design a roll having a diameter of about 5 3/4 inches, with the angle α=15°, depth D=0.06 inch and the spacing C=0.4 inch, the height or gap G was set at 0.06 inch for treating chips having a maximum thickness of slightly over 0.25 inch using a disc with W=0.06 inch, S=0.3 inch, Z=0.06 inch and d=0.055.
As above indicated mating surfaces extend such that the ridges or crowns 26 are substantially perpendicular to the longitudinal axis of the land areas 12 in the nip formed between the surfaces 10 and 22.
In the embodiment illustrated in FIG. 3 and 4 the roll 24 is mounted on a fixed housing in a device somewhat similar to that described in the above referred to Lapointe patent. The chips enter each nip 32 formed between the surface 10 on the rotating disc 34 and the surface 22 on the mating rotating roll 24. The disc 34 as illustrated in FIG. 4 is provided with the spaced land areas 12 in the form of concentric rings extending around the axis of rotation of the disc 34 as shown for example in FIG. 4 with the valleys 14 as formed by the walls 16, 18 and the bottom wall 20 there between.
The preferred crusher arrangement uses the disc 34 and roll 24 in combination similar to that disclosed in the said Lapointe U.S. Pat. No. 3,962,966 modified to use the orienting mechanism described in copending Lapointe application 360,827 filed March 23, 1982. The chips enter through the inlet 36 and are flung by flingers or orienting bars 38 up an inclined orienting surface 40 wherein the chips are laid on their larger area face and the oversized material acted on to reduce it to a certain predetermined thickness to pass out through the outlet passage 42 formed by a pair of substantially parallel walls one on the disc 46 and the other on the housing 44, for further details see the said copending Lapointe application. Chips that pass through outlet 42 are flung from the disc 46 onto the disc 34 for movement through the nip 32 between the disc 34 and the roll 24. A plurality of rolls 24 will be spaced around the circumference of the disc 34 to provide a plurality of spaced apart nips 32 through which chips may pass. The disc 46 preferably is driven by a drive belt 48 at a speed higher than the speed of rotation of the disc 34 which is driven via a belt 50 i.e. the angular velocity of the disc 46 is higher than that of the annular ring formed by the disc 34. The rolls 24 may also be driven via a suitable motor such as that indicated at 52 through suitable belt drives such as that schematically illustrated at 54 in FIG. 3. The roll surface 22 preferably will travel at about the same speed and in substantially the same direction as the surface of the disc through the nip 32. (Obviously the surface 22 of roll 24 at any one time has the same tangential velocity in the direction of movement through the nip while the tangential velocity of the disc varies with the radius and thus provision must be made for the drive for the roll 24 to permit some slippage. Usually the surface 22 will be driven by drive 52 at a velocity substantially equal to the velocity of the surface 10 at the mid point of the nip and obviously if the roll 24 is driven by the surface 10 through a chip the velocity of the roll will vary depending on the radial location of the chip relative to the surface 10.
The surface of the disc 46 preferably will be slightly lower than the wall of the outlet 42 formed by the disc 46 so that the chips pass from the disc 46 and at least part way across the surface 10 in free flight.
If desired the present invention may also be applied to a pair of mating compression rolls such as those indicated at 56 and 58 in FIG. 5, the roll 56 may be provided with a working surface equivalent to the surface 10 as illustrated in FIG. 1 and the roll 58 with a surface configuration such as the surface configuration 22 used on the roll 24. In any event the nip 60 formed between these rolls will function in a manner quite similar to the nip 32 formed between the roll 24 and the annular disc 34. However, the radius of the two rolls may be larger than 12 inches for this embodiment provided the approach angle between the two rolls will accept the chips to be fed thereto.
In any embodiment employing the present invention the concept is to have a pressure applied to the chips at spaced locations longitudinally and transversly of the chips. These spaced locations as indicated by the blackened areas 62 are formed where the land area mates with the apexes 26 of the teeth on the roll 24 as shown in FIG. 6 as the apex 26 of one of the teeth comes down and approaches the surface 10 of say the disc 34, pressure points are developed between the land areas 12 and the adjacent points or crowns 26. The first tooth 26 shown in FIG. 6 provides a first line of areas 62 extending across the chip generally indicated at 64 by a dot dash line, press the chip between the surfaces 10 and 22 at points 62, this pressing tends to force the chip into the valleys between the land areas 12 and thereby deflect the chip beyond the elastic limit while simultanously compressing the chip (depending on the chip thickness) so that internal cracking and fissuring occurs either longitudinally of the chip or transversly of the chip depending on the orientation of the chip relative to the teeth 26 and to the land areas 12 but substantially always along fibre boundries. These pressure points 62 are repeated further along the chip 64 as indicated by the areas 62' as defined by the second tooth 26' the spacing between the pressure points 62 and 62' being determined by the spacing between the tips 26 of the teeth and the rate of rotation of the surface 22 relative to the movement of the chip 64. Obviously the illustration is schematic and the pressure points 62 will take place in the same vertical plane as the pressure points 62' in spaced locations along the surfaces 10 and 22.
In operation the surfaces 10 and 22 cooperate in the nip to apply forces as above described to compress thick chips with localized spaced high pressure points or with thinner chips to apply local spaced compression points without substantially densifying the surface at the chip to resist impregnation yet with sufficient force to fissure and crack oversize chips to render them more easily impregnated and facilitate more uniform impregnation of the chips.
Having described the invention, modifications will be evident to those skilled in the art without departing from the spirit of the invention as defined in the appended claims. | The cooperating surfaces defining a pressing nip in a chip crusher are formed with specific patterns to treat the chips by fissuring to facilitate penetration by cooking chemical for the making of pulp for papermaking and the like. One of the surfaces is provided with a plurality of land areas separated by valleys, the land areas being substantially continuous and extending in the direction of movement of the surface as it passes through the crushing nip. The surface cooperates with the surface of a roll which defines the other side of the nip, the roll surface is provided with a plurality of teeth with the crown of each tooth defining a line preferably extending substantially perpendicular to the direction of movement of the roll surface through the nip. | 3 |
BACKGROUND OF THE INVENTION
The present invention relates to an improved synthesis of both enantiomers of ipsenol and ipsdienol in high optical purity and in good yields, as well as an improved method for the isoprenylation of aldehydes and novel intermediates therefor.
Bark beetles of the Ips genus are major pests in conifer forests and are responsible for mass attacks in pine forests. These beetles signal aggregation and colonization by phermonal communication which involves three terpene alcohols, ipsenol (2-methyl-6-methylene-2,7-octadien-4-ol), ipsdienol (2-methyl-6-methylene-7-octen-4-ol) and cis-verbenol. The absolute configurations of the terpene alcohols identified as the principal components of these attractants have been determined as (S)-(-)-ipsenol, (S)-(+)-ipsdienol and (1S, 4S, 5S)-cis-verbenol. Their antipodes are biologically inactive. See for example J. Vite et al. Nature, Vol. 272, pp. 817-818 (27 Apr. 25, 1978); R. Silverstein et al., Science, Vol. 54, pp 509-510 (28 Oct. 1966).
The five-spined engraver beetle, Ips grandicollis, aggregates only in response to (S)-ipsenol, both ipsenol and ipsdienol constitute aggregation pheromones of the spruce-infesting bark beetle, Ips typographus and ipsdienol is present in the population attractant of Ips sexdentatus.
Because these compounds are important as lures for attracting and trapping these pests on a large scale, various investigators have attempted to develop satisfactory processes for the production of the biologically active isomers.
Many syntheses of racemic ipsenol and ipsdienol are available in the literature. See for example, Bubnov, Yu et al., Tetrahedron Lett. 1987, 26, 2797; Silverstein, R. M. et al., Science, 1966, 154, 509; Karlsen, S. et al., Acta chem. Scan. B, 1970, 30, 664; Cazes B. et al., J. Organometal Chem. 1979, 177, 67; A. Hosomi et al., Tetrahedron Leters, 1979, 429; Y. Masaki et al., J. Chem. Soc. Perkin Trans.I, 1984, 1289; and Klusener, P. A. A. et al., J Org. Chem. 1987, 52, 5261.
Mori first synthesized both of these pheromones in optically active form and assigned their configurations. Mori's initial synthesis of ipsenol, starting from leucine, was both lengthy and cumbersome and resulted in low chemical ( about 5%) and optical yields (80%). K. Mori: Tetrahedron Lett. 1975, 2187; K. Mori: Tetrahedron 1976, 32, 1101. Later, Mori modified his procedure to obtain optically pure ipsenol (≧99%) but the overall yield still remained low. Ipsdienol starting from (R)-malic acid gave 90% ee for the pheromone. K. Mori: Tetrahedron Lett. 1976, 1609; K. Mori et al., Tetrahedron 1979, 35, 933.
Additional enantioselective syntheses have since been reported. Ohloff et al. prepared ipsdienol in 91% ee (R) and 80% ee (S) from the enantiomers of verbenone via the corresponding β-pinene-4-ols, G. Ohloff et al.: Helv. Chim Acta. 1977, 60, 1496. Norin prepared racemic ipsdienol via sensitized photooxidation of commercially available myrcene followed by acid catalyzed rearrangement, P. Baeckstrom et al.: Acta Chem. Scand. B. 1983, 37, 1. Oxidation of the tertiary alcohol obtained from photooxidation to myrcenone, followed by asymmetric reduction of the carbonyl moiety using Noyori's Binal-H (J. Am. Chem. Soc., 1984, 106, 6709, 6717) provided both enantiomers of ipsdienol in 63% ee. Modified Binal-H provided ipsdienol of even lower optical purity. P. Baeckstrom et al, supra. H. Yamamoto's condensation of isovaleraldehyde with the tartrate ester of allenyl boronic acid provided the corresponding homopropargylic alcohol which was further elaborated to the 2-brominated alcohol. Protection of the alcohol as the tetrahydropyranyl ether followed by treatment with the vinyl Grignard reagent and deprotection furnished (-) ipsenol in ≧99% ee. See N. Ikeda et al., J. Am. Chem. Soc. 1986, 108, 143.
Despite the substantial efforts of numerous investigators, prior art procedures are generally expensive, multistepped processes that produce the desired opticals in low yields and/or low optical purity. The present invention provides an elegant process for producing these important pheromones in high optical purity and excellent yields compared with the prior art.
SUMMARY OF THE INVENTION
The present invention provides a one-pot reaction sequence for the facile synthesis of either enantiomer of ipsenol or ipsdienol. The process is equally applicable to the isoprenylation of other aldehydes of varying steric and electronic environments.
Generally speaking, the process of this invention for synthesizing either enantiomer of ipsenol or ipsdienol in ≧96% ee comprises treating (reacting) isovaleraldehyde or β,β-dimethylacrolein, respectively with d Ipc 2 B(2'-isoprenyl) and l Ipc 2 B(2'-isoprenyl), depending upon the desired end product. The process is represented by the following reaction scheme: ##STR1##
Generally speaking, B-2'-isoprenyldiisopinocampheyl boranes, d or l Ipc 2 BIpn, respectively, are synthesized by the reaction of2'-isoprenylpotassiumwith B-methoxydiisopinocampheyl borane ( d or l Ipc 2 BOMe) followed by treatment with BF 3 .EE according to the following reaction scheme: ##STR2## Condensation of the B-2'-isoprenyldiisopinocampheylborane with aldehydes provides the corresponding chiral homoallylic alcohols as illustrated in the examples which follow.
Generally speaking, the above general method was applied to the preparation of both enantiomers of the pheromones ipsenol and ipsdienol by reacting the stereoisomers of B-2'-isoprenyldiisopinocampheylborane with isovaleraldehyde and β,β-dimethylacrolein, respectively. In this case, the product alcohols were isolated by a non-oxidative workup, i.e. addition of acetaldehyde to the reaction mixture, converting the borinate intermediate to the corresponding boronate, with simultaneous displacement of α-pinene. Addition of diethanolamine precipitated the boron components and the products were isolated from the filtrate by distillation.
In another embodiment, the present invention provides a general process for the synthesis of diterpenyl-(2'-isoprenyl)borane, R' 2 B(2'-isoprenyl), wherein R' is isopinocampheyl, 2-isocaranyl and 4-isocaranyl and comprising metallating isoprene to form H 2 C═C(CH 2 K)--CH═CH 2 and attaching the 2'-isoprenyl group to the boron of a (terpenyl) 2 BX derivative, wherein X is selected from the group comprising OR, OMe, F, Cl, Br or I, wherein R is alkyl. The terpene may be selected from the group consisting of α-pinene, 3-carene and 2-carene.
The process of this invention may be employed for the chiral isoprenylation of aldehydes by reacting the desired aldehyde with a compound of the formula R' 2 B(2'-isoprenyl) wherein R' is isopinocampheyl, 2-isocaranyl and 4-isocaranyl.
The intermediates R' 2 B(2'-isoprenyl) are novel compounds.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Techniques for handling air-sensitive compounds, as described by H. C. Brown et al., Organic Synthesis via Boranes, Wiley Interscience: New York, 1975, Chapter 9, incorporated by reference herein, were followed. Spectroscopic measurements ( 1 H and 11 B NMR and IR) were made with standard instruments. GC analyses were done on a Varian Aerograph Series 1200 gas chromatograph having a flame ionization detector and integrated with a Hewlett-Packard 3380 S integrator. GC columns, 1/8"×12', were packed with 10% SP-2100 (Supelco, Inc.) on Chromosorb W (Supelco, Inc.,(80-100 mesh) or 5% Carbowax 1540 (Supelco, Inc.) on Chromosorb W (80-100 mesh). Analyses of the MTPA esters or MCF derivatives were performed on a Hewlett- Packard 5890A gas chromatograph using a Supelcowax glass capillary column (15 m), methylsilicone capillary column (50 m) or a SPB-5 capillary column (30 m) at appropriate temperatures and integrated using a Hewlett-Packard 3390A integrator.
THF was distilled from sodium benzophenone ketyl and stored under nitrogen in an ampule. BMS, 9-BBN, α-pinene, 2,2,5,5-tetramethylpiperidine (TMP), n-butyllithium, t-BuOK, BF 3 .EE, acetaldehyde, 2-methylpropionaldehyde, benzaldehyde, isovaleraldehyde, β,β-dimethylacrolein (3-methyl-2-butenal), α-methoxy-α-trifluoromethylphenylacetic acid (MTPA), and menthyl chloroformate (MCF) were all obtained from Aldrich Chemical Company, Milwaukee, Wis. MTPA was converted to the acid chloride using the literature procedure.
In the examples, the ee value was established either by capillary GC examination of diastereomeric α-methoxy-α-trifluoromethylphenylacetates (MTPA) or (-)menthylchloroformate (MCF) derivatives or by comparison of the observed optical rotation with those reported in the literature.
EXAMPLE 1
B-Isoprenyl-9-BBN
2,2,5,5-Tetramethylpiperidine (TMP)(3.5 g, 4.2 mL, 25 mmol) was added at 0° C. to a solution of n-butyllithium (10.8 mL of 2.3M solution in hexane, 25 mmol) in a mixture of THF (5.5 mL) and hexane (2.5 mL) contained in a 200 mL round-bottomed flask fitted with a side-arm and connecting tube as usual (H. C. Brown et al., Organic Synthesis via Boranes, Wiley Interscience: New York, 1975, Chapter 9). After 15 minutes, the solution of LiTMP was cooled to -78° C. and a solution of t-BuOK (2.8 g, 25 mmol in 15 mL THF) was added slowly to provide a clear yellow solution of the potassium salt of TMP. Subsequently, isoprene (3.7 mL, 37 mmol) was added slowly to the reaction mixture over a period of five minutes while keeping the temperature of the now red solution between -78° to -60° C. After completion of the addition, the dry ice-acetone bath was replaced by a CHCl 3 /liquid nitrogen bath (-60° C.) and stirred for an additional 15 minutes to ensure complete metallation. The potassium salt of isoprene was recooled to -78° C. and 25 mL of a 1M solution of B-methoxy-9-BBN in THF was added slowly over a period of 5 minutes. The 11 B NMR spectrum of the mixture showed a singlet at δ2.5 corresponding to an `ate` complex which was treated with 1.33 equiv of BF 3 .EE (4 mL, 33 mmol) at -78° C. (5 min) to provide the isoprenylborane as a thick slurry. ( 11 B NMR: δ78 ppm). This intermediate was used as such for isoprenylation of aldehydes.
EXAMPLE 2
(±)-2-Methyl-6-methylene-7-octen-4-ol, Racemic Ipsenol
Isovaleraldehyde (2.15 g, 2.68 mL, 25 mmol) in ether (6 mL) was added dropwise to a rapidly stirred solution of B-isoprenyl-9-BBN (Example 1), maintained at -78° C. Stirring was continued for 1 h, when the 11 B NMR spectrum of an aliquot showed a peak at δ52 ppm corresponding to a borinate indicating completion of the reaction. The reaction mixture was warmed to room temperature, quenched with methanol and oxidized with alkaline H 2 O 2 . Work up as described by H. C. Brown, Organic Synthesis via Boranes, Wiley Interscience, New York, 1975, Chapter 9, followed by distillation (bp 92°-94° C./19 mm Hg) provided the title compound. Yield: 2.5 g, 65%.
EXAMPLE 3
(±)-4-Methylene-5-hexen-2-ol
Following the method of Example 2, the title compound was prepared from acetaldehyde in 65% yield. bp 67°-68° C./19 mm Hg. 1 H NMR: (CDCl 3 ), δ: 1.2 (3H, d, J=6Hz), 2.3 (2H, m), 3.9 (1H, m), 4.8-5.3(4H, m), 6.3 (1H, dd, J=12 Hz). 13 C NMR: (CDCl 3 ), δ: 22.94, 41.69, 65.96, 114.0, 118.09, 138.59, 143.25.
EXAMPLE 4
2-Methyl-5-methylene-6-hepten-3-ol
Following the method of Example 2, the title compound was prepared from 2-methylpropionaldehyde in 65% yield. bp 90°-93° C./25 mm Hg. 1 H NMR: (CDCl 3 ), δ: 0.96 (6H, d, J=6 Hz), 1.6-2.5 (3H, m), 3.65 (1H, m), 4.9-5.3 (4H, m), 6.3 (1H, dd, J=12 Hz). 13 C NMR: (CDCl 3 ), δ: 17.58, 18.67, 33.51, 36.8, 74.03, 114.13, 118.21, 138.54, 143.67.
EXAMPLE 5
3-Methylene-1-phenyl-4-penten-1-ol
Following the method of Example 2, the title compound was prepared from benzaldehyde in 60% yield. bp 70° C./1.0 mm Hg. 1 H NMR: (CDCl 3 ), δ: 2.8 (2H, m), 4.8 (1H, br t), 5.0-5.4 (4H, m), 6.4 (1H, dd, J=12 Hz), 7.3 (5H, s).
EXAMPLE 6
2-Methyl-6-methylene-7-octen-4-ol (ipsenol)
Following the method of Example 2, the title compound was prepared at 0° C. from isovaleraldehyde in 65% yield. bp 92°-94° C./19 mm Hg. 1 H NMR: (CDCl 3 ), δ0.88 (3H, d, J=6 Hz), 0.92 (3H, d, J=6 Hz), 1.2 (2H, m), 1.8 (2H, m), 3.72 (1H, m), 5.0-5.3 (4H, m), 6.3 (1H, dd, J=12 Hz). 13 C NMR: (CDCl 3 ), δ: 22.26, 23.63, 24.87, 40.79, 46.69, 67.88, 114.59, 118.86, 139.05, 143.7.
EXAMPLE 7
2-Methyl-6-methylene-2,7-octadien-4-ol (ipsdienol)
Following the method of Example 2, the title compound was prepared from β,β-dimethylacrolein in 60% yield, bp 51°-54° C./1.5 mm Hg. 1 H NMR: (CDCl 3 ), δ: 1.66 (3H, d, J=6 Hz), 1.72 (3H, d, J=6 Hz), 2.39 (2H, d, J=7 Hz), 4.46 (1 H, m), 4.95-5.36 (5H, m), 6.32 (1H, dd, J=12 Hz). 13 C NMR: (CDCl 3 ), δ: 18.52, 25.96, 40.4, 67.05, 114.4, 119.08, 128.18, 135.58, 139.24, 149.3.
EXAMPLE 8
B-Isoprenyldiisopinocampheylborane ( d Ipc 2 BIpn)
This intermediate was prepared following the method for the preparation of the achiral agent of Example 1. Isoprenylpotassium, prepared by the method of L. Brandsma et al., J. Chem. Soc. Chem. Commun. 1985, 1677, (25 mmol) was treated with B-methoxydiisopinocampheylborane, prepared from (+)-α-pinene (25 mmol) in THF at -78° C. 11 B NMR showed a singlet at δ2 ppm corresponding to the `ate` complex. This `ate` complex was treated with 1.33 equiv of BF 3 .EE (4 mL, 33 mmol) at -78° C. (5 min) to provide the title compound as a thick slurry. This was used as such for the asymmetric isoprenylation of aldehydes.
EXAMPLE 9
(R)-(+)-2-Methyl-6-methylene-7-octen-4-ol, (+)-Ipsenol
Isovaleraldehyde (2.15 g, 2.68 mL, 25 mmol) in ether (6 mL) was added dropwise to a rapidly stirred solution of B-isoprenyldiisopinocampheylborane, d Ipc 2 BIpn, maintained at -78° C. Stirring was continued for 1 h, when the 11 B NMR spectrum of an aliquot showed a peak at δ52 ppm corresponding to a borinate indicating completion of the reaction. The reaction mixture was warmed to 0° C. and acetaldehyde (2.1 mL, 37.5 mmol) was added when one equiv of α-pinene was eliminated. 11 B NMR showed a peak at δ32 ppm corresponding to a boronate. THF was substituted with EE and 1.1 equiv. of diethanolamine (2.6 mL, 27.5 mmol) was added and stirred for 2 h. The precipitated boron components were filtered and the filtrate was concentrated and distilled (92°-94° C./19 mm Hg) to yield 2.3 g (60%) of (+)-ipsenol. [α] D =+17.3° (c 1, MeOH) which corresponds to 93.7% ee. The spectral properties were identical to the racemic mixture of Example 6.
EXAMPLE 10
(S)-(+)-2-Methyl-6-methylene-2,7-octadien-4-ol, (+)-Ipsdienol
β,β-Dimethylacrolein (2.15 g, 2.68 mL, 25 mmol) in ether (6 mL) was added dropwise to a rapidly stirred solution of B-isoprenyldiisopinocampheylborane, maintained at -78° C. Stirring was continued for 1 h, when the 11 B NMR spectrum of an aliquot showed a peak at δ52 ppm corresponding to a borinate indicating completion of the reaction. The reaction mixture was warmed to 0° C. and acetaldehyde (2.1 mL, 37.5 mmol) was added when one equiv of α-pinene was eliminated. 11 B NMR showed a peak at δ32 ppm corresponding to a boronate. THF was substituted with EE and 1.1 equiv of diethanolamine (2.6 mL, 27.5 mmol) was added and stirred for 2 h. The precipitated boron components were filtered and the filtrate was concentrated and distilled (51°-54° C./1.5 mm Hg) to yield 2.3 g (60%) of (+)-ipsdienol. [α] D =+13.18° (c 1, MeOH) which corresponds to 96% ee. The spectral properties of (+)-ipsdienol were identical to that of the racemic mixture.
EXAMPLE 11
B-Isoprenyldiisopinocampheylborane ( l Ipc 2 BIpn)
This intermediate was prepared following the method of Example 8. B-methoxydiisopinocampheylborane, prepared from (-)-α-pinene was used instead of the methoxy derivative prepared from (+)-α-pinene and the same reaction sequence followed to obtain the title compound as a thick slurry. This was used as such for the asymmetric isoprenylation of aldehydes.
EXAMPLE 12
(S)-(-)-2-Methyl-6-methylene-7-octen-4-ol, (-)-Ipsenol
Isovaleraldehyde (2.15 g, 2.68 mL, 25 mmol) in ether (6 mL) was added dropwise to a rapidly stirred solution of B-isoprenyldiisopinocampheylborane, l Ipc 2 BIpn, maintained at -78° C. Stirring was continued for 1 h, when the 11 B NMR spectrum of an aliquot showed a peak at δ52 ppm corresponding to a borinate indicating completion of the reaction. The reaction mixture was warmed to 0° C. and acetaldehyde (2.1 mL, 37.5 mmol) was added when one equiv of α-pinene was eliminated. 11 B NMR showed a peak at δ32 ppm corresponding to a boronate. THF was substituted with EE and 1.1 equiv. of diethanolamine (2.6 mL), 27.5 mmol) was added and stirred for 2 h. The precipitated boron components were filtered and the filtrate was concentrated and distilled (92°-94° C./19 mm Hg) to yield 2.5 g (65%) of (-)-ipsenol. [α] D =-17.67 ° (c 1, MeOH) which corresponds to 96% ee. The spectral properties were identical to the racemic mixture of Example 6.
EXAMPLE 13
(R)-(-)-2-Methyl-6-methylene-2,7-octadien-4-ol, (-)-Ipsdienol
β,β-Dimethylacrolein (2.15 g, 2.68 mL, 25 mmol) in ether (6 mL) was added dropwise to a rapidly stirred solution of B-isoprenyldiisopinocampheylborane (Example 11), maintained at -78° C. Stirring was continued for 1 h, when the 11 B NMR spectrum of an aliquot showed a peak at δ52 ppm corresponding to a borinate indicating completion of the reaction. The reaction mixture was warmed to 0° C. and acetaldehyde (2.1 mL, 37.5 mmol) was added when one equiv of α-pinene was eliminated. 11 B NMR showed a peak at δ32 ppm corresponding to a boronate. THF was substituted with EE and 1.1 equiv of diethanolamine (2.6 mL, 27.5 mmol) was added and stirred for 2 h. The precipitated boron components were filtered and the filtrate was concentrated and distilled (51°-54° C./1.5 mm Hg) to yield 2.3 g (60%) of (-)-ipsdienol. [α] D =- 13.11° (c 1, MeOH) which corresponds to 96% ee. The spectral properties of (-)-ipsdienol were identical to that of the racemic mixture.
EXAMPLE 14
B-Isoprenylbis(2-isocaranyl)borane (2-Icr 2 BIpn)
This intermediate was prepared following the method for the preparation of the isopinocampheyl reagent (example 8), B-methoxybis(2-isocaranyl)borane, prepared from (+)-2-carene. (H. C. Brown et. al. J. Am. Chem. Soc. 1990, 112, 2389) was used instead of the methoxy derivative from (+)-α-pinene and the same sequence followed to obtain the title compound. This was used for the asymmetric isoprenylation of aldehydes.
EXAMPLE 15
B-Isoprenylbis(4-isocaranyl)borane (4-Icr 2 BIpn)
This intermediate was prepared following the method of Example 14. B-Methoxybis(4-isocaranyl)borane, prepared from (+)-3-carene was used instead of the methoxy derivative from (+)-2carene and the same sequence followed to obtain the title compound. This was used as such for the asymmetric isoprenylation of aldehydes.
EXAMPLE 16
(R)-(+)-2-Methyl-6-methylene-7-octen-4-ol, (+)-Ipsenol
Isovaleraldehyde (2.15 g, 2.68 mL, 25 mmol) in ether (6 mL) was added dropwise to a rapidly stirred solution of B-Isoprenyldiisopinocampheylborane, d Ipc 2 BIpn, maintained in THF/EE (1:2) at -100° C. Stirring was continued for 6 h, when the 11 B NMR spectrum of an aliquot showed a peak at δ52 ppm, corresponding to a borinate indicating completion of the reaction. The reaction mixture was warmed to 0° C. and acetaldehyde (2.1 mL, 37.5 mmol) was added when one equiv of α-pinene was eliminated. 11 B NMR showed a peak at δ32 ppm corresponding to a boronate. The solvents were removed in vacuo and EE (20 mL) was added, followed by 1.1 equiv. of diethanolamine (2.6 mL, 27.5 mmol). Stirring was continued for 2 h and the precipitated boron components were filtered and the filtrate concentrated. Distillation (92°-94° C./19 mm Hg) provided 2.3 g (60 %) of (+)-ipsenol, [α] D =+18.5° which corresponds to 100% ee. The spectral properties were identical to the sample obtained from example 9.
EXAMPLE 17
(S)-2-Methyl-6-methylene-2,7-octadien-4-ol, (+)-Ipsdienol
The title compound was prepared using d Ipc 2 BIpn (example 8) following the method for the preparation of Ipsenol (example 16). β,β-dimethylacrolein was used instead of isovaleraldehyde in example 16, and the same sequence followed to obtain 2.5 g (65%) of (+)-ipsdienol: bp 51°-54° C./1.5 mm Hg. [α] D =13.7° (c 1, MeOH) which corresponds to 100% ee.
EXAMPLE 18
(S)-(-)-2-Methyl-6-methylene-7-octen-4-ol, (-) Ipsenol
The title compound was prepared using a procedure similar to Example 16. B-Isoprenyldiisopinocampheylborane, prepared from (-)-α-pinene (example 11) was used instead of the one prepared from (+)-α-pinene (example 8) and the same reaction sequence in example 16 followed to obtain 2.5 g (65%) of the title compound [α] D =-18.5° which corresponds to 100% ee.
EXAMPLE 19
(R)-(-)-2-Methyl-6-methylene-2,7-octadien-4-ol, (-)-Ipsdienol
The title compound was prepared following the method for the preparation of (+)-Ipsdienol (example 18). The reagent l Ipc 2 BIpn from example 11 was used and the same reaction sequence as described in example 17 followed to obtain 2.5 g (65%) of (-)-ipsdienol: bp 51°-54° C./1.5 mm Hg. [α] D =-13.7° (c 1, MeOH) which corresponds to 100% ee.
EXAMPLE 20
(S)-(-)-2-Methyl-6-methylene-7-octen-4-ol, (-)-Ipsenol
Isovaleraldehyde (2.15 g, 2.68 mL, 25 mmol) in ether (6 mL) was added dropwise to a rapidly stirred solution of B-Isoprenylbis(2-isocaranyl)borane, 2-Icr 2 BIpn (example 14) maintained in THF at -78° C. Stirring was continued for 1 h, when the 11 B NMR spectrum of an aliquot showed a peak at δ52 ppm corresponding to a borinate indicating completion of the reaction. The reaction mixture was warmed to 0° C. and acetaldehyde (2.1 mL, 37.5 mmol) was added when one equiv of 2-carene was eliminated. 11 B NMR showed a peak at δ32 ppm corresponding to a boronate. The solvents were removed in vacuo and EE (20 mL) was added, followed by 1.1 equiv of diethanolamine (2.6 mL, 27.5 mmol). Stirring was continued for 2 h and the precipitated boron components were filtered and the filtrate concentrated. Distillation (92°-94° C./19 mm Hg) provided 2.3 g (60%) of (-)-ipsenol, [α] D =-18.1° which corresponds to 98% ee. The spectral properties were identical to the sample obtained from example 9.
EXAMPLE 21
(R)-(+)-2-Methyl-6-methylene-7-octen-4-ol, (+)-Ipsenol
The title compound was prepared by using the reagent 4-Icr 2 BIpn (example 15) and isovaleraldehyde as in Example 19 but using -100° C. for the reaction (conditions in example 17). (+)-Ipsenol (2.5 g, 65%) was obtained after work up. [α] D =+18.5° which corresponded to 100% ee.
EXAMPLE 22
(S)-2-Methyl-6-methylene-2,7-octadien-4-ol, (+)-Ipsdienol
The title compound was prepared using 2-Icr 2 BIpn (example 14) following the method for the preparation of Ipsdienol (example 19). β,β-dimethylacrolein was used instead of isovaleraldehyde in example 21 and the same sequence followed to obtain 2.5 g (65%) of (+)-ipsdienol: bp 51°-54° C./1.5 mm Hg. [α] D =+13.7° (c 1, MeOH) which corresponds to 100% ee.
EXAMPLE 23
(S)-2-Methyl-6-methylene-2,7-octadien-4-ol, (+)-Ipsdienol
The title compound was prepared using 4-Icr 2 BIpn (example 15) following the method for the preparation of Ipsdienol (example 21). The reaction was carried out at -100° C. and the same sequence followed to obtain 2.5 g (65%) of (+)-ipsdienol: ipsdienol: bp 51°-54° C./1.5 mm Hg. [α] D =+13.7° (c 1, MeOH) which corresponds to 100% ee.
Generally speaking, the processes of this invention can be run from room temperature to -100° C., but enantioselectivities improve with lower reaction temperatures. Hence, low reaction temperatures are preferred. Especially preferred are reaction temperatures from -78° to -100° C. | An improved process for preparing either optically pure enantiomer of the bark beetle pheromones ipsenol and ipsdienol is provided. The process is also applicable to the condensation of aldehydes of widely varying properties to the corresponding chiral alcohol. This invention also concerns novel intermediates R' 2 B(2'-isoprenyl) wherein R' is isopinocampheyl, 2-isocaranyl and 4-isocaranyl. | 2 |
FIELD OF THE INVENTION
[0001] The present invention relates generally to video games, and more specifically to special effects used in video games.
BACKGROUND OF THE INVENTION
[0002] The fun and excitement associated with many video games is increased when audio and visual effects are similar to real-life sounds and images. This is especially true with action combat games involving shooting and other weapons. Sounds may be related to an environmental activity or an impact activity.
[0003] Environmental activity refers to activity surrounding the video game characters, such as flies buzzing, water running in a river, footsteps of a character running, a car engine running, etc. The sounds associated with environmental activities are typically not reactive, but rather are static in that they exist to enhance the presence of the object or person (“object” is used hereafter to refer to a physical object, person, or other living creature). Impact activity refers to “direct hits” on an object, such as a car blowing up from an explosive, a window shattering from a bullet, an alien or bad guy being shot, etc. The sounds associated with impact activities are typically due to the “direct hit.”
[0004] In real life, objects may also react to secondary effects of an environmental or impact activity. For example, if a bomb explodes, a nearby fence may rattle in response to the resulting shockwave. Thus, the overall video game experience could be enhanced if the effect associated with an environmental and/or impact activity includes an output asset (e.g., audio, visual, audio-visual effect) triggered by a force other than a direct hit, to create a more real-life sensation during video game play. In other words, the asset is output in response to a secondary effect of the activity, such as the shockwave of an explosion. This adds to the player's envelopment in the virtual play space.
SUMMARY OF THE INVENTION
[0005] The output of an object in a video game includes an asset triggered by a secondary force, i.e., a force other than a direct hit on the object. Typically the force will be a secondary force from an environmental activity or an impact activity. The trigger is accomplished by a “reactive emitter,” which is a property associated with the object that is programmed into the video game to react to the secondary force.
[0006] In preferred embodiments of the present invention, a method includes assigning a coverage zone to an activity in the video game, assigning a detection zone to an object in the video game, determining the coverage zone intersects with the detection zone, and causing the object to emit the asset based on the intersection of the coverage zone and the detection zone. The coverage zone is the area affected by a secondary effect of the activity. The detection zone is an area in the vicinity of the object.
[0007] The asset may be an audio asset, a video asset, or an audio-video asset. The coverage zone and detection zone are typically substantially spherical, defined by a coverage radius and detection radius respectively. The activity is typically an explosion, and the secondary effect is a shockwave of the explosion.
[0008] The output asset may vary in size/intensity based on the magnitude of intersection of the coverage zone and the detection zone. The output asset may also vary based on the type of object and/or the type of activity. If the output asset includes an audio component, the properties affected by these parameters may be pitch, volume, duration, and frequency.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a flowchart of a method of the present invention.
[0010] FIG. 2 is a geometric diagram showing intersections of various two-dimensional coverage zones and detection zones.
[0011] FIG. 3 illustrates various 3 -dimensional coverage zones and detection zones.
[0012] FIG. 4 shows a partial scene of a video game illustrating the coverage zone of an explosion intersecting with detection zones of various objects.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0013] Preferred embodiments of the present invention will now be described with reference to the above-described drawings. Beginning with FIG. 4 , a partial scene 400 from within a video game is shown, in which an explosion 430 is occurring. The scene 400 includes a building wall 410 , a car 415 , a barrel 420 , and a fence 425 . Also shown in FIG. 4 are dotted lines representing coverage zone 435 of the explosion 430 , and detection zones 440 , 445 , 450 , and 455 , of the wall 410 , car 415 , barrel 420 , and fence 425 respectively. The dotted lines are for illustration purposes only, and would not be visible during video game play as part of the scene 400 or otherwise.
[0014] Coverage zone 435 is shown as substantially circular, as are detection zones 445 , 450 , and 455 . These zones could be any shape, including three-dimensional shapes such as substantially spherical. Detection zone 440 of wall 410 is shown as three-dimensional, specifically in the shape of a rectangular prism corresponding to the shape of the wall. Coverage zone 435 of explosion 430 represents the area affected by the shockwave of the explosion. In FIG. 4 , coverage zone 435 extends radially outward from the point of origin of explosion 430 , and intersects with each of detection zones 410 , 415 , 420 , and 425 . Thus, in accordance with preferred embodiments of the present invention, the shockwave of explosion 430 in scene 400 would cause each of objects 410 , 415 , 420 , and 425 to emit one or more assets. For example, as further described herein: wall 410 might shake, creak, and/or wobble etc.; car 415 might roll, tilt, spin, become airborne, have an airbag go off, have an alarm go off, and/or have the horn honk, etc.; barrel 420 might crack, split, roll, spin, become airborne, and/or discharge some or all of its contents, etc.; and fence 425 might rattle, buckle, and/or bend, etc. Various real-life sounds could be associated with the aforementioned.
[0015] Turning now to FIG. 1 , a method to output an asset in a video game in accordance with the present invention is illustrated in a flowchart. The method begins at Step 100 . At Step 105 , a coverage zone is assigned to a secondary effect of an activity in the video game. The activity may be any activity generating a shockwave, pressure wave, or other secondary force. For example, the activity may be an explosion (as illustrated in FIG. 4 ) from a bomb, grenade, rocket, missile, or any other type of explosive. The activity may be a weather event or natural phenomenon such as an earthquake, lightning strike, hurricane, tornado, tsunami, volcanic eruption, etc. The activity may be a sonic boom from an aircraft, or a force wave from a supernatural power. The activity may be recoil or reverberation from firing a weapon, or a shockwave from a large building falling or an aircraft crashing.
[0016] The coverage zone represents the area affected by the secondary effect of the activity. Typically the coverage zone is substantially spherical, and thus is defined by a coverage radius. When the activity is an explosion, the coverage radius is a blast radius. However, the coverage zone may be any geometric shape or irregular area, and may even be three-dimensional. Various three-dimensional coverage zones are shown, e.g., in FIG. 3 . Specifically: a cylindrical zone 305 is shown for an activity centered at 320 ; a conical zone 310 is shown for an activity centered at 325 ; and a spherical zone 315 is shown for an activity centered at 330 .
[0017] The coverage zone is programmed into the video game by associating the zone with the activity. The coverage zone may be constant for the activity, or may vary depending on other parameters. For example, a certain type of explosion may always have a blast radius of 15 feet, or that type of explosion may have a blast radius varying from 5 feet to 25 feet, depending on parameters such as which character triggered the explosion, the weather conditions, whether the weapon causing the explosion has been enhanced, etc. Or the range may be randomly generated. Multiple activities may have corresponding coverage zones assigned to their corresponding secondary effects at Step 105 . The coverage zones may be assigned as part of the video game development, or dynamically during video game play.
[0018] At Step 110 , a detection zone is assigned to an object in the video game. Objects may be fences, barrels, walls, windows, cars or other vehicles, boxes, poles, trees, bushes, dirt, leaves, rocks, water, structures, or anything else. Multiple objects may be assigned corresponding detection zones at Step 110 . Assignment of detection zones to objects may occur before, after, or simultaneously with assigning coverage zones to the secondary effects of activities at Step 105 . The detection zones may be assigned as part of the video game development, or dynamically during video game play. Various detection zones 440 , 445 , 450 , and 455 are shown in FIG. 4 . Typically detection zones are substantially spherical, and thus are defined by a detection radius.
[0019] During video game play, when an activity occurs having a coverage zone, if the coverage zone intersects with the detection zone of an object, the object will emit an asset based on the intersection. Determination of the intersection occurs at Step 115 , and is discussed in more detail herein with reference to FIGS. 2 and 3 . The object emits the asset at Step 120 . The asset may be audio, visual, audio-visual, or even another sensory asset such as a smell, flavor, or tactile output. The asset may have properties associated therewith, and the values of those properties are referred to herein as the asset's payload. For example, a sound asset may have properties of pitch, volume, duration, frequency, etc., each assigned a value. A video asset may have properties of direction, speed, condition, color, axis of rotation, discharge, deformation, etc., each assigned a value.
[0020] As an example, if an explosion occurs generating a shockwave with a coverage zone intersecting the detection zone of a barrel, the barrel may shake, roll, break, and discharge its contents, all with accompanying lifelike sounds. Similarly, if the coverage zone intersects the detection zone of a car, the car may spin, become airborne, and have its hood pop off when it lands, all with accompanying lifelike sounds. If the coverage zone intersects the detection zone of a fence, the fence may rattle, buckle, or dislodge, all with accompanying lifelike sounds. If the coverage zone intersects the detection zone of a wall or building, the wall or building may shake, crumble, crack, or have portions dislodged, all with accompanying lifelike sounds.
[0021] The scope and extent of the asset or assets emitted may be determined by various factors. For example, an object may have fixed assets associated therewith. In such a case, the object would emit the same asset(s) whenever its detection zone intersected a coverage zone. Or an object may have various fixed assets associated therewith corresponding to various known activities. In such a case, the asset(s) emitted would depend on the activity associated with the coverage zone intersecting the object's detection zone. Various objects may have various assets assigned thereto depending on the type of the object. Objects may be classified into different types such as human, inanimate, extraterrestrial, etc., and may be further classified into sub-types such as by size, stability, foundation, material composition, etc. Such classifications may be determined at the programming level (as may classifications of activities).
[0022] Further, the payload of an asset may depend on various factors. For example, the payload may vary as the magnitude of the intersection between the coverage zone and the detection zone varies. In other words, if an object's detection zone barely intersects an activity's coverage zone, the payload may be minimal, whereas if the object's detection zone significantly intersects an activity's coverage zone, the payload may be more significant. The payload may also vary depending on the type of object (as previously described) and/or the type of activity. Activities may be classified into different types such as weather, explosion, structural, supernatural, etc. Or each activity may have its own unique payload associated therewith. An activity with a short duration and high frequency may cause the object to emit a short more “pingy” payload as compared to a longer low-frequency activity.
[0023] Turning now to FIG. 2 , intersections of various two-dimensional coverage zones ( 205 , 210 , 220 , and 225 ) and detection zones ( 215 and 230 ) are shown in a geometric diagram. The coverage zones 205 , 210 , 220 , and 225 represent areas affected by secondary effects of various activities centered at 235 , 240 , 250 , and 255 respectively. The zones are all circular, and thus have coverage radii 265 , 270 , 280 , and 285 respectively. The activities may occur substantially simultaneously or at different times during the video game. The detection zones 215 and 230 represent areas in the vicinities of objects centered at 245 and 260 respectively, and are also circular and thus have detection radii 275 and 290 respectively.
[0024] As can be seen, not all of the coverage zones 205 , 210 , 220 , and 225 intersect both of the detection zones 215 (for object centered at 245 ) and 225 (for object centered at 260 ). Starting with coverage zone 205 of activity centered at 235 , this zone does not intersect with either of detection zones 215 or 230 . Thus, occurrence of this activity would not cause either of those objects to emit an asset. Coverage zones 210 and 220 intersect detection zone 215 , but does not intersect detection zone 230 . Thus, occurrence of the activities centered at 240 and 250 would cause the object centered at 245 to emit an asset, but would not cause the object centered at 260 to emit an asset. And coverage zone 225 intersects detection zone 230 , but does not intersect detection zone 215 . Thus, occurrence of the activity centered at 255 would cause the object centered at 260 to emit an asset, but would not cause the object centered at 245 to emit an asset.
[0025] As already mentioned, the output asset may vary in intensity based on a determination of the magnitude of intersection of the coverage zone and the detection zone. For example, the asset's payload may increase as the magnitude of the intersection between the coverage zone and the detection zone increases. Determination of the size/intensity of the payload may be based on a percent of intersection of the coverage zone and detection zone, and/or some other linear or exponential function dependent on proximity of the activity to the object, intervening obstacles, etc. In FIG. 2 , for example, coverage zones 210 and 220 intersect with detection zone 215 at 295 and 297 respectively. Those intersections are small compared to intersection 299 of coverage zone 225 and detection zone 230 . Thus, if a payload is directly proportional to the magnitude of intersection, the payload of the object centered at 260 based on the activity centered at 255 would be greater than the payload of the object centered at 245 based on either of the activities centered at 240 or 250 .
[0026] As an example of modifying assets based on the magnitude of intersection of the applicable coverage zone and detection zone, a barrel at 245 might react to activity at 240 or 250 by slightly wobbling or tilting over, with a low volume corresponding sound. On the other hand, a barrel at 260 might react to activity at 255 by being ejected into the air and breaking apart, with loud thuds as the pieces land. Any or all of audio properties of pitch, volume, duration, and frequency, may be adjusted accordingly based on the magnitude of intersection.
[0027] Also as already mentioned, the output asset may vary based on the type of object and/or the type of activity. For example, all metal objects may have specific sounds associated with them, whereas all liquid objects may have other specific sounds associated with them. Objects may be classified as broadly or narrowly as is desired. Likewise, activities may be classified as broadly or narrowly as desired. An object's output asset(s) may depend on the type of activity associated with the coverage zone. Such assets for any object or type/class of objects may be mapped to any activity or class/type of activity as desired.
[0028] Additionally, detection areas may vary for an object, depending on the type of activity. For example, a barrel might have one detection zone for weather-related activities, and a different detection zone for explosions. Or the barrel might have one detection zone for earthquakes, and a different detection zone for lightning strikes. Detection zones may also be randomly generated.
[0029] Although particular embodiments have been shown and described, the above description is not intended to limit the scope of these embodiments. While embodiments and variations of the many aspects of the invention have been disclosed and described herein, such disclosure is provided for purposes of explanation and illustration only. Thus, various changes and modifications may be made without departing from the scope of the claims. Accordingly, embodiments are intended to exemplify alternatives, modifications, and equivalents that may fall within the scope of the claims. The invention, therefore, should not be limited, except to the following claims, and their equivalents. | A reactive emitter associated with an object in a video game emits an asset in response to a secondary effect of an activity that occurs in the video game within a vicinity of the object. | 0 |
This invention relates to perforating devices adapted for use in oil and gas wells; and more particularly relates to a novel and improved modular through-tubing casing gun for use in perforating cased well bores beneath a tubing string.
BACKGROUND AND FIELD OF THE INVENTION
In oil and gas perforating operations, much greater penetration is achieved in casing gun assemblies than the through-tubing units. In particular, the through-tubing units presently in use may contain the same amount of charge as casing guns but have not been able to penetrate as deeply into the formation owing to their wider cone angle and limitations in overall size imposed by the inner concentric tubing strings through which they are deployed. The through-tubing devices are principally employed where high pressure and well conditions are such that perforating with casing gun assemblies is not practical. Typical of the casing gun types of perforating assemblies are those disclosed in prior U.S. Pat. No. 4,253,523 and prior pending patent application, U.S. Ser. No. 299,479, filed Sept. 4, 1981, now U.S. Pat. No. 4,467,878 for SHAPED CHARGE AND CARRIER ASSEMBLY THEREFOR.
It is now proposed to provide a through-tubing perforating assembly capable of achieving much greater penetration and specifically in such a way as to be able to employ standard casing gun charges possessing the desired penetrating configuration while withstanding high pressure conditions; yet can be passed through relatively small diameter tubing to the desired zone or formation to be perforated.
Representative U.S. Letter Patents disclosing through-tubing perforating apparatus are U.S. Pat. Nos. 2,746,828 to H. H. Rachford, Jr.; 3,207,072 to J. R. Holden; 3,234,875 to E. O. Tolson; 3,238,872 to L. Zernow et al; 3,244,101 and 3,268,016 to W. T. Bell; 3,259,064 to N. G. Owens; 3,302,567 to A. A. Venghiattis; 3,419,070 to E. A. Ernst; 3,517,745 to G. O. Suman, Jr.; and 3,627,045 to M. P. Lebourg.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide for a novel and improved perforating assembly adaptable for use in perforating subsurface oil and gas subsurface formations which is versatile and of simplified construction.
It is another object to provide for a novel and improved form of perforating assembly which is capable of perforating either through casing or tubing and which is capable of using shaped charges normally employed in casing guns.
Another object of the present invention is to provide for a through-tubing perforating assembly which employs casing gun charges to achieve narrow cone angles with much greater penetration than heretofore possible and permits disposition in phase or out of phase through an adjustable length carrier containing the desired number of charges.
It is a still further object of the present invention to provide for a through-tubing perforating assembly which can be made up of the desired number of casing gun charges disposed either in centered or off-center relationship within a casing and capable of withstanding extremely high pressures at the bottom of a well.
It is an additional object of the present invention to provide in a perforating assembly for novel and improved modular high-strength sections for mounting and support of a series of shaped charges either in phase or in out of phase relation to one another.
In accordance with the present invention, there has been devised a novel and improved form of through-tubing perforating assembly conformable for use in various types of cased well bores but having particular application in those in which a tubing string is positioned within the cased well bore and where extremely high pressures are encountered at the bottom of the well. In the preferred form of assembly, a plurality of shaped charges of the casing gun type are mounted in a modular carrier wherein the carrier comprises a plurality of generally tubular members interconnected in end-to-end relation to one another, each tubular member having an internal cavity defining a horizontally directed seating portion for supporting one of the shaped charges therein. An end cap is disposed at the lower end of the modular carrier, and a blasting cord extends continuously through the tubular members across one end of the shaped charges for detonating the charges when positioned opposite to that part of the formation to be perforated. Each of the tubular members is characterized in particular by the mounting and disposition of the shaped charges such that they can be cradled or supported within the tubular member and anchored in place by interconnection of each next tubular member in succession without the use of separate fastening elements. The desired number of charges and tubular members can be interconnected in end-to-end relation with the blasting cord extending through grooved portions passing across slotted ends of each of the shaped charges so that when the tubular members are made up together the shaped charge in each tubular member is caused to bear firmly against the blasting cord at its slotted end to assure detonation of the charge when the blasting cord is ignited. The tubular members are such that they can be aligned with their respective charges extending either in phase or in 180° out of phase relation to one another and suspended downwardly through an inner tubing string to the desired depth. The charges may be placed either in centered relation to the cased wall bore or in off-center relation and may be suspended by various well-known means, such as, a wireline tool.
Other objects, advantages and features of the present invention will become more readily appreciated and understood when taken together with the following detailed description in conjunction with the accompanying drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a view partially in section illustrating the disposition of a preferred form of perforating assembly in off-center relation to a casing opposite to the zone in a subsurface formation to be penetrated;
FIG. 2 is an end view of one of the modules comprising the preferred form of perforating assembly of the present invention;
FIG. 3 is a cross-sectional view taken about lines 3--3 of FIG. 2;
FIG. 4 is a cross-sectional view taken about lines 4--4 of FIG. 3;
FIG. 5 is a cross-sectional view taken about lines 5--5 of FIG. 2; and
FIG. 6 is a vertical section view of the preferred form of perforating assembly aligned for use in centered relation to a casing in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
A preferred form of perforating assembly 10 is comprised of a plurality of tubular modules 12 interconnected in end-to-end relation to one another and terminating at their lower end in a nose cone 14 and at their upper end in a tubing support connector 16. The tubular modules 12 as well as nose cone 14 have upwardly directed socket ends, for example, as illustrated at 18 in FIG. 3 with diametrically opposed internal locking dogs or teeth 19 adapted to interengage with external locking dogs or teeth 20 at the lower end of each module 12 as well as the lower end of the upper support connector 16. Thus, each lower complementary end 22, as shown in FIGS. 3, 4 and 5, is of a reduced external diameter slightly less than the diameter of the internal wall surface of the upper socket ends 18 and is provided with diametrically opposed dogs 20 which are advanced past the diametrically opposed internal locking dogs 19 then rotated into locking engagement behind the dogs as shown in FIG. 3. A circumferential groove 24 is spaced above the locking dogs 20 to accommodate an O-ring seal 25 which effects sealed engagement between the reduced lower end 22 and upper socket end 18 of each of the modules when interconnected in end-to-end relation to one another.
Each of the tubular modules 12 is provided intermediately of its upper and lower ends with an internal cavity defining a horizontally disposed cradle or support 26 for horizontal disposition of a shaped charge C, as illustrated in FIGS. 5 and 6. A Prima cord 30 is passed downwardly through the entire assembly of modules from the upper support connector 16 and through vertically extending slots 31 disposed at the ends of the supports 26 in the modules so as to position the Prima cord at the nose end of the shaped charges C positioned therein. The lower extreme end of the Prima cord 30 is inserted into an arcuate groove 32 located internally of the lower extremity of the nose cone 14. As shown in FIG. 1, the upper end of the Prima cord 30 is secured to a blasting cap 34 in a conventional manner, the cap 34 having leads 35 passing upwardly through a central passage 36 in the upper support connector 16 for connection to a wireline tool in a manner hereinafter described. In this relation, the Prima cord 30 is preferably of rectangular cross-section.
Considering in more detail the construction of each modular tubing section 12, each is correspondingly formed with a thin-walled socket end 18 having an inner wall surface 40 of a diameter to permit insertion of the external wall surface 42 of the male end of the next module. As described, the external diameter of the male end is reduced by an amount corresponding to the thickness of the socket end 18 and is relatively thick-walled with an inner wall surface 44 forming a central passage in communication with the socket end 18. The cradle support 26 is formed at the upper end of the passage 44 by arcuate recessed portions 46 in diametrically opposed sides of the inner wall surface and which together form a generally semi-cylindrical, horizontal support for the lower half of the shaped charge C.
As seen from FIG. 6, an upper tubing adaptor module 12' is comprised of a hollow cylindrical body 52 having a lower end 20 corresponding to the male end 20 of modular sections 12 together with an oppositely directed male end 20' which corresponds to the male end 20 but is provided with one or more circumferential grooves 24' to facilitate interlocking sealed connection to lower socket end 54 on the tubing support connector 16. The support connector 16 also is of tubular construction having a lower socket end 18' provided with diametrically opposed internal locking dogs 19'. The support connector tapers rearwardly as at 58 into a threaded end portion 59 to facilitate interconnection to a wireline tool, not shown, in a well-known manner. A central passage 62 extends through the support connector 16 into communication with the socket end 18' to permit extension of the connecting wires or leads from the wireline tool. Preferably, the support connector 16 is composed of a high strength metal which will not be damaged when the charges C are detonated so that the connector can be retrieved along with the wireline tool. However, the modules 12 are preferably composed of a ceramic material of sufficiently high strength to withstand substantial pressures downhole but which will be completely disintegrated by the detonation of the charges.
In practice, the modules 12 are assembled first by positioning the lower end of the Prima cord 30 in the slot 32 formed in the interior of the end cap 14, followed by interconnection of the first module 12 to the end cap 14. The Prima cord 30 is passed upwardly through the module 12 and inserted into the slot 31 prior to placement of a shaped charge C on the cradle 26 within the module. A slotted end C' of the charge C is aligned with the slot 31 so as to sandwich the Prima cord 30 therebetween. A second module 12 is then interlocked as described with the first module, the lower edge of the second module bearing lightly against the upper surface of the charge C so as to securely retain the charge in position within the first module. A series of modules 12 are successively assembled in the manner described with respect to the first and second modules in accordance with the number of charges C to be employed. For the purpose of illustration, the number of charges may vary over a wide range with each charge containing from 6 grams to 22 grams of explosive. The specific makeup of the charges, as such, forms no part of the present invention. However, of particular importance is the fact that the modular carrier is so constructed as to permit use of casing gun charges, such as, those of the type disclosed in my hereinbefore referred to U.S. Pat. No. 4,253,523 and pending patent application.
Alignment markings or arrows 50 on the external surfaces of the modules 12 will assure exact alignment of the charges C within the modules so that the charges can be directed precisely in the same direction or with adjacent charge positioned at 180° to one another throughout the assembly; i.e., the charges can be disposed either in phase or in out of phase relation to one another depending upon the specific application of the assembly. In FIG. 1, assembly 10 is shown suspended in off-center relation to a casing S which is cemented in a well bore. The tubing string T is sealed off at its lower end by a packer P above the section of the casing to be perforated, but imposes definite limitations on the size or diameter of the assembly 10, since it must be lowered through the tubing string. In the application shown in FIG. 6, where it is desired to maintain the assembly 10 in centered relation to a casing, suitable centralizers are employed between the assembly 10 and the wireline which will expand into engagement with the casing and maintain the assembly 10 in the center of the casing. In such applications, it is desirable to position the charges C in out-of-phase relation to one another in order to penetrate through diametrically opposed sides of the casing and into the formation.
From the foregoing, it will be readily appreciated by those skilled in the art that the through-tubing perforating assembly of the present invention offers the ability to enhance production capabilities on new and old wells. For instance, in deep wells where high pressure and temperature can complicate completion, the present invention offers the ability to maximize perforation performance for operations of up to 25,000 psi at 650° F.; or, where formation characteristics dictate multiple zone completion, it offers maximized perforation performance. Moreover, where perforation characteristics dictate massive interval completion, the present invention offers the ability to perforate at whatever shot density is desired and over the desired interval by making repeated runs. A modular perforating assembly of the type described further eliminates downhole obstruction below the tubing, which in some cases eliminates the possibility and avoids the necessity of workover procedures, such as, zone isolation. In large diameter holes completed through-tubing, the modular perforating assembly of the present invention offers the ability to use the same charges with the same perforation performance as normally would be expected using a hollow steel carrier gun in casing applications.
Accordingly, the present invention offers a total expendible, acid-resistant ceramic carrier for use with powdered metal-shaped charges for debris-free completion. As a result, it is readily conformable for use with any superior shaped-charge technology with the added advantage of offering maximum perforation performance unaffected by high pressure and temperature conditions.
Thus, while there has been described a preferred embodiment of the present invention, it is to be understood that various modifications and changes may be made as will be apparent to those skilled in the art without departing from the spirit and scope of the present invention as defined by the appended claims. | A novel and improved form of through-tubing perforating assembly conformable for use in various types of cased well bores having particular application in those in which a tubing string is positioned within the cased well bore and where extremely high pressures are encountered at the bottom of the well. A plurality of shaped charges are mounted in a modular carrier comprised of a plurality of generally tubular members interconnected in end-to-end relation to one another, each tubular member having an internal cavity defining a horizontally directed seating portion for supporting one of the shaped charges therein. An end cap is disposed at the lower end of the modular carrier, and a blasting cord extends continuously through the tubular members across one end of the shaped charges for detonating the charges when positioned opposite to that part of the formation to be perforated. | 4 |
This application claims priority to U.S. Provisional Application Ser. No. 60/523,329 which was filed on Nov. 19, 2003.
BACKGROUND OF THE INVENTION
This invention generally relates to an illuminated pointer for an instrument panel. More particularly, this invention relates to an illuminated pointer that provides independent pointing on two scales.
Instrument panels for a vehicle include several gauges for displaying and conveying information to a driver. The instrument panel typically includes a speedometer along with other gauges such as a tachometer, battery level indicator, and oil pressure gauge. Typically a pointer is mounted to move relative to the fixed graphical image on each gauge.
The pointer is typically one of two basic types, either a non-active pointer or an active pointer. A non-active pointer is illuminated by a light source mounted to a circuit board positioned behind a light transparent output shaft. Light is reflected into the pointer and scattered to illuminate the pointer. An active pointer includes a light source secured to the moving pointer.
In each configuration, the pointer includes a body portion that extends from a first end coupled to a motor and a second end that moves relative to the graphical image. The body portion is typically painted to block and direct light to provide consistent illumination throughout visible portions of the pointer. In many instances, the speedometer will include both an English scale in miles per hour (MPH) and a Metric scale in Kilometers per hour (Km/h). The English scale is usually placed radially about an axis of rotation of the pointer. The Metric scale is then placed in a smaller radial arrangement within the English scale. A single pointer is utilized to read each scale. Such single pointers typically extend to the larger English scale and block the corresponding reading on the Metric scale. The blocked and covered reading is the reading that relates to the actual reading provided by the pointer. Accordingly, such pointers make it difficult to accurately read the Metric or secondary scale.
It is known to provide a pointer with a hollowed out center section. The center section provides for viewing of the smaller Metric scale, however, the accuracy is limited due to the absence of a true pointer as is provided for the larger English or primary scale. Further, the hollowed out center section of the pointer creates challenges to illuminating the tip of the pointer by conventional methods.
Accordingly, it is desirable to develop and design an illuminated pointer that provides accurate visual indication on two scales simultaneously.
SUMMARY OF THE INVENTION
An example illuminated pointer includes a first pointer for indicating on a primary scale and a second pointer for indicating on a secondary scale. The pointer includes three light reflecting surfaces for illuminating the outer pointer and the inner pointer.
The illuminated pointer includes a first pointer and a second pointer. The first pointer points to a numerical value on a primary scale and the second pointer points to a numerical value on a secondary scale. The first pointer is generally elliptically shaped with an opening. The opening provides for clear viewing of the secondary scale. The second pointer extends partially into the opening to point to a numeric value on the secondary scale. The combination of the opening and the second pointer provides an accurate and readable visual reference of vehicle speed as indicated on the secondary scale.
The pointer assembly is illuminated in both the first pointer and the second pointer. The first pointer and the second pointer are substantially evenly illuminated utilizing a single light source. Light from the light source propagates into the pointer assembly and is scattered on a bottom surface. The base includes three inclined reflective surfaces, each of which reflects a portion of light emitted from the light source along and through first and second legs of the first pointer and through the second pointer. The inclined reflective surfaces include angles relative to an axis that decreases the amount of light that passes through the reflective surfaces. This results in an increase in light that is reflected within the pointer assembly, resulting in a desirable increase in overall brightness of the pointer assembly.
Accordingly, the pointer assembly of this invention provides an illuminated pointer that provides an accurate visual indication on two scales simultaneously.
These and other features of the present invention can be best understood from the following specification and drawings, the following of which is a brief description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plane view of a speedometer including two scales and an illuminated pointer according to this invention.
FIG. 2 is a perspective view of an illuminated pointer according to this invention.
FIG. 3 is a cross-sectional view of an illuminated pointer with a light source.
FIG. 4 is an enlarged view of the illuminated pointer including light reflecting surfaces.
FIG. 5 is a cross-sectional view through a section of the illuminated pointer.
FIG. 6 is a view of a bottom side of the illuminated pointer.
FIG. 7 is a perspective view of another illuminated pointer according to this invention.
FIG. 8 is a perspective view of still another illuminated pointer according to this invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows an instrument panel 10 including a speedometer 11 . The speedometer 11 includes a primary scale 12 and a secondary scale 14 . The scales are represented on a graphical display 16 . The example illustrated includes the primary scale 12 in English units indicating a speed of a vehicle in miles per hour (MPH) and the secondary scale 14 in Metric units indicating a vehicle speed in Kilometers per hour (KM/h). As appreciated the units on the primary and secondary scales 12 and 14 can be of known scale or reversed as desired for a specific application.
A pointer assembly 18 includes a first pointer 20 and a second pointer 22 . The first pointer 20 points to a numerical value on the primary scale 12 and the second pointer points to a numerical value on the secondary scale 14 . The first pointer 20 is a generally elliptical shape with an opening 28 . The opening 28 provides for clear viewing of the secondary scale 14 . The second pointer 22 extends partially into the opening 28 to point to a numeric value on the secondary scale 14 . The combination of the opening 28 and the second pointer 22 provides an accurate and readable visual reference of vehicle speed as indicated on the secondary scale.
Referring to FIG. 2 , the pointer assembly 18 includes a base 30 that is supported atop a shaft 32 . A first leg 24 and a second leg 26 extend from the base and project radially outward. Each of the first leg 24 and the second leg 26 terminate at a tip 34 . The tip 34 provides the visual reference pointer to the numeric value reading on the graphical display 16 . The second pointer 22 also extends from the base between both the first and second legs 24 , 26 into the opening 28 . The second pointer 22 terminates at a tip 36 disposed within the opening and along a common axis 35 with the tip 34 of the first pointer 20 . The overall length of the first pointer 20 from the base 30 to the tip 34 corresponds with the radius of the primary scale 12 . Further the length of the second pointer 22 from the base 30 to the tip 36 corresponds with the radius of the secondary scale 14 .
Referring to FIG. 3 , the pointer assembly 18 is illuminated in both the first pointer 20 and the second pointer 22 . The first pointer 20 and the second pointer 22 are substantially evenly illuminated utilizing a single light source 42 . In the example embodiment the light source 42 is mounted to a printed circuit board (PCB) 40 . The shaft 32 is hollow and serves as a light guide for light emitted from the light source 42 . The base of the pointer assembly 18 includes three surfaces that provide total internal reflection. Reflected light from the light source 42 propagates into the pointer assembly 18 and is scattered on a bottom surface. The base 30 includes the light reflecting surfaces, one of which is indicated at 52 .
Referring to FIG. 4 , the base 30 includes the three inclined reflective surfaces 52 , 54 and 56 . Each of the inclined reflective surfaces 52 , 54 , and 56 reflect a portion of light emitted from the light source 42 along and through the first and second legs 24 , 26 of the first pointer 20 and through the second pointer 24 . The length shape and angle of each inclined reflecting surface is determined to direct light along a desired path through the different portion of the pointer assembly. A worker versed in the art with the benefit of this disclosure would understand how to configure a light-reflecting surface to direct light along a desired path.
Further, the inclined reflective surfaces 52 , 54 , 56 include angles relative to the axis 64 and light emitted through the shaft 32 that decrease the portion of light that passes through the reflective surfaces. This results in an increase in light that is reflected within the pointer assembly, resulting in a desirable increase in light that is delivered to the lower scattering surface of the pointer assembly 18 . This results in an increase in overall brightness of the pointer assembly 18 .
Referring to FIG. 5 , the second pointer 22 is shown in cross-section and includes a bottom surface 48 a top surface 46 and sides 50 . The cross-section is substantially rectangular with the bottom surface 48 having a width 62 that is smaller than a width 60 of the top surface 46 . The bottom surface 48 provides for scattering of light that then passes to the upper surface 46 and is visible to a vehicle operator. The change in height, and width of the surfaces of the pointer 22 provide for adjustment to illumination characteristics of the pointer assembly 18 . Such adjustments provide for the even and uniform illumination of the pointer 22 . As appreciated, although a cross-section of the second pointer 22 is shown, the cross-sections for the first and second legs 24 , 26 of the first pointer 20 are similar and may also be adjusted to provide desired illumination characteristics.
Referring to FIG. 6 , the lower surface 48 of the pointer assembly 18 is covered with a reflective white layer 44 . The reflective white layer 44 is applied to the pointer assembly 18 to prevent illumination from leaking through the bottom surface 48 . Light is reflected off the reflective white layer 44 back toward the top surface 46 . The use of the reflective white layer 44 improves light efficiencies. A worker versed in the art with the benefit of this disclosure would understand that any material known in the art may be utilized for the reflective white layer 44 .
Referring to FIG. 7 , another pointer assembly 70 includes the first pointer 20 and the second pointer 22 . The pointer assembly 70 includes three inclined reflective surfaces 72 , 74 , and 76 that are offset from the axis 64 and shaft 32 . The inclined reflective surfaces 72 , 74 , and 76 are positioned on a side opposite the first pointer 20 and the second pointer 22 to reflect light from a light source disposed in a non-axial position with the shaft 32 . The three inclined reflective surfaces 72 , 74 , and 76 receive and reflect light from a light source 42 that is positioned on an opposite side of the axis 64 from the first and second pointers 20 , 22 .
Referring to FIG. 8 , another pointer assembly 80 includes inclined reflective surfaces 82 , 84 , and 86 on a side of the axis 64 common to the first pointer 24 and the second pointer 22 . In the example pointer assembly 80 a light source 42 is provided on a common side of the axis 64 , and the position of the inclined reflective surfaces 82 , 84 , and 86 . As appreciated, in some application it is desirable to utilize a non-axially positioned light source and still provide substantially even illumination throughout the pointer assembly.
Although a preferred embodiment of this invention has been disclosed, a worker of ordinary skill in this art would recognize that certain modifications would come within the scope of this invention. For that reason, the following claims should be studied to determine the true scope and content of this invention. | An illuminated pointer includes an outer pointer that surrounds an inner pointer. The outer pointer extends from a base and is generally elliptical. The inner pointer extends from the base into the void of the outer pointer. The illuminated pointer utilizes a single light source for illuminating both the outer and inner pointer. The inner pointer provides easier reading of a dual scale gauge such as with a speedometer having both English and Metric speed scales. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to optical fiber and optical sensors and, more particularly, to a unique combination of wavelength modulated optical sensors coupled to a spectrograph detector and an optical fiber transmission link.
2. The Prior Art (The citations are expanded below)
Conventional oceanographic instruments make use of electrical sensors and electrical wires and use a time consuming measurement process. With research vessel time becoming more expensive and difficult to get, the necessity for accurate expendable oceanographic sensors and probes is becoming more apparent. Present expendable technology makes use of electromagnetically active wires and sensors and are produced primarily by Sippican Corporation of Marion, Mass., Magnavox Inc., and Sparton Inc.; the latter two are involved in the manufacture of expendable acoustic hydrophones called sonobuoys. Sippican Corporation has manufactured the expendable bathythermograph since 1965; this is called an XBT and measures the temperature and time as the device falls through the ocean. Time is theoretically related to depth and the information from the thermistor is relayed back to the surface vessel through a thin wire that unreels from the probe vehicle as it falls. This wire breaks when it is unreeled and the measurement is complete; the probe vehicle and sensor then descend to the bottom of the ocean. Sippican also manufactures expendable sound velocimeters (XSV, 1979) that measure the speed of sound and time, expendable current profilers (XCP, 1983) that measure the magnetic field and time, and expendable air launched bathythermographs (AXBT, 1984) that are dropped from aircraft into the ocean; an expendable conductivity, temperature, and depth probe (XCTD, 1985) is now being developed to measure conductivity, temperature, and time. The expendable current profiler was originally developed in a non-expendable form by Sandford and Drever in 1978 at the Woods Hole Oceanographic Institution; also other versions of the expendable air launched bathythermographs are manufactured by Magnavox Inc., and Hermes Inc.
Electrical expendable probes, transmission links, and sensors suffer from the following problems:
1. Depth sensing is intractable,
2. Conductivity, and therefore, salinity measurement is difficult and unreliable,
3. Failure rate is high due to electrical insulation leaks,
4. The thermal sensor time constant is large, and
5. Wire transmission link data rate is low.
The simple design and rugged and electromagnetically passive nature of optical fibers and optical sensors offers solutions in these areas. The present electrical expendable instruments measure time and, assuming a constant free-fall velocity, relate it to depth; this method has an average error of 31/2% with an even greater error for the deeper probes. Optical pressure sensors used to measure depth have accuracies generally at 0.4%. Optical index of refraction sensors do not have the drift and instabilities created by the films and polarization encountered in electrical conductivity probes. Also, this electrically passive nature eliminates the failures caused by electrical insulation breaks and the radio frequency pick-up in the probe and transmission link of conventional expendables. The ocean is also an electrical conductor. In the past data from expendable instruments has not been fully trusted by oceanographers except, perhaps, for survey work. Noncatastrophic wire insulation leaks result in signal errors that are not immediately apparent and require elaborate screening procedures for the data to be believed. In regards to the thermal time constant, the absence of electrical insulation covering the thermal sensor offers an improved time response potential over the electrical thermistor. Finally, the optical fiber transmission link is capable of passing 200 megabits/sec of data, enough for a hundred or more sensors, as opposed to the two or three limit imposed by thin electrical wire.
In the past the cost of optical fiber has been prohibitive for its use in expendable probes. Seven years ago its cost was $1.50 per meter; today the retail quote is $0.15/m with wholesale discounts beyond this, and the prospect is for the price to continue to decrease. The manufacturers, such as Corning Glass Works, have stated that the long term goal is to make glass fiber equivalent to copper wire in price.
In addition to the above oceanographic and underwater sensing applications, remote optical sensing has application in industrial process control, cryogenic environments, and in fiber optic data- and tele-communications. Evanescent wave spectroscopy and liquid chromotography are two industrial applications of fiber optic refraction sensors as described by Lew, et. al. (1984) and David et. al. (1976) respectively. The use of optical pressure, temperature, and refraction sensors to avoid electrical hazard in explosive environments is discussed by Sharma and Brooks (1980). Finally, local area data and tele-communication networks are increasingly using optical fibers, and optical pressure, temperature, and liquid level refraction sensors are a needed addition for such purposes as building security as discussed by Harmer (1983).
In surveying the specific optical sensing techniques presently in use, we find that those sensors that use amplitude modulation are not sensitive enough and have drift and calibration problems, whereas other optical sensors that use phase modulation are sensitive to too many factors, particularly in remote applications. Christensen (1979) has developed a band edge semiconductor temperature sensor that is amplitude modulated; the drift is only partly compensated for by using a reference signal, and the instrument must be recalibrated every few hours. Also, Spillman and McMahon (1982) have developed a birefringent pressure sensor which is also amplitude modulated, and Mahrt, et. al. (1982) has developed an in-situ critical angle refractometer that has a wire link return and is not expendable. In regards to phase modulation the Naval Research Laboratory in Washington, D.C. has developed interferometers for optical acoustic pressure sensing in the oceans; they have been able to attain very high sensitivities, but with concomitant environmental noise. This work is reviewed by Giallorenzi, et. al. (1982).
The use of optical fiber as a transmission link in underwater sensing is relatively new, but has had several successful applications. Gregg, et. al. in 1982 made use of the high data rate capability of optical fiber to service six electrical sensors in a free-fall microstructure profiler; Lund beginning in 1983 uses optical fiber for in-situ algae mapping by stimulating and detecting fluorescent emissions; and the Naval Ocean systems Center established the feasibility of using optical fibers for expendable communications links in 1982. A caution to this, however, was added by S. Hanish in 1981 at the Naval Post Graduate School in Monterey; he found that thermal and mechanical stresses produced by the ocean environment created a moderate to severe effect on phase sensing. Remote oceanic interferometric sensing techniques are not currently practical.
Each of the foregoing prior art devices are useful in particular applications. However, it would be an advancement in the art to provide a combination of temperature, pressure, and index of refraction sensors that were accurate and free from drift, that could be used to make measurements in remote and inaccessible locations such as the oceans, and that could even be expendable. Such a unique combination of sensors, detector, and transmission link is disclosed and claimed herein.
REFERENCES CITED ABOVE
I. Expendable Electrical Ocean Sensors
(a) Sippican Ocean Systems, Marion, Mass. Expendable Bathythermograph (XBT, 1965); Expendable Sound Velocimeter (XSV, 1979); Expendable Current Profiler (SCP, 1983); Air Launched Expendable Bathythermographs (AXBT, 1984); Expendable Conductivity, Temperature, and Depth (SCTD, 1985). Also "Expendable Air Probe," 1971, Pat. No. 3,569,512 and "Bathythermograph System," 1965 (Buzzards Bay Corp.), Pat. No. 3,221,556.
(b) Interstate Electronics Corporation, Anaheim, Calif. Disposable Underway Bathythermometer (DUBAT, 1965). Contract No. bsr-93315. Final Engineering Report U.S. Navy Bureau of Ships, May 1966.
(c) Sandford, T. and R. Drever, Woods Hole Oceanographic Institution. Deep Sea Research, Vol. 25, 1978 pp 183-210. Expendable Electromagnetic Velocity Profiler (XEMVP, 1982).
(d) Magnavox Inc. Expendable Hydrophones (Sonobouys). Expendable Air Launched Bathythermographs (AXBT, 1984).
(e) Hazeltine Inc., Commack, N.Y. Expendable Hydrophones (Sonobuoys).
(f) Hermes, Inc., Expendable Air Launched Bathythermographs (AXBT, 1984).
(g) Spartan, Inc. Expendable Hydrophones (Sonobuoys).
II. Optical Ocean Sensors
(a) Mahrt, K-H., H. C. Waldmann, and W. Kroebel, 1982. "A Remote Index of Refraction Probe". Proceedings of the Oceans '82 Conference, IEEE/MTS, Washington, D.C.
(b) Christensen, D. 1979: "Semiconductor Temperature Sensor". U.S. Pat. No. 4,136,566.
(c) Spillman, W. and D. McMahon, 1982: "Multimode Fiber-Optic Hydrophone based on the Photoclastic Effect". Applied Optics, Vol. 21, No. 19, p. 3511-3514.
(d) Giallorenzi, R., J. Bucaro, A. Dandridge, G. Sigel, J. Cole, S. Rashleigh, and R. Priest, 1982:"Optical Fiber Sensor Technology". IEEE Journal of Quantum Electronics, Vol. QE-18, No. 4, p. 626-665.
III. Optical Industrial Sensors
(a) Lew, A., C. Depeursinge, F. Cochet, H. Berthou, and O. Parriaux, 1984: "Single-Mode Fiber Evanesent Wave Spectroscopy". Proceedings of the Second International Conference on Optical Fiber Sensors, VDE-Verlag GmbH Berlin, FRG, September 1984, p. 71.
(b) David, D., D. Shaw, and H. Tucker, 1976: "Design, Development, and Performance of a Fiber Optics Refractometer: Application to HPLC". Review of Scientific Instruments, Vol. 47, No. 9, p. 989.
(c) Sharma, M. and R. Brooks, 1980: "Fiber-optic Sensing in Cryogenic Environments". SPIE Vol. 224, p. 46.
(d) Harmer, A., 1983: "Optical Fiber Sensor Markets". Proceedings of the First International Conference on Optical Fiber Sensors, IEE, London, p. 53.
IV. Optical Fiber Transmission Links for Ocean Sensors
(a) Gregg, M., W. Nodlund, E. Aagaard, and D. Hirt, 1982: "Use of a Fiber-Optic Cable with a Free-Fall Microstructure Profiler". Proceedings of the Oceans '82 Conference, IEEE/MTS, 1982.
(b) Lund, T., 1983: "A Fiber Optics Fluorimeter for Algae detection and Mapping". Proceedings of the First International Conference on Optical Fiber Sensors. IEE, Savoy Place, London, England and OSA, Washington, D.C. April 1983.
BRIEF SUMMARY AND OBJECTS OF THE INVENTION
This invention relates to a unique combination of optical sensors, an optical fiber transmission link, and a spectrograph detector. The instrument relies upon the wavelength shift of the band edges of various optical and infrared filters with changes in the temperature, pressure, and index of refraction of the environment. The signals are wavelength multiplexed in a single optical fiber to be read at a remote location. The specific techniques that are used here are the change in wavelength of the absorption/transmission band edge of such materials as selenium with temperature, the change in the wavelength of the multiple transmission band edges of such birefringent materials as quartz with pressure, and the change in wavelength of the reflection/refraction band edge of such prismatic materials as glass with the index of refraction. The three band edge signals are in different parts of the visible-infrared region of the spectrum and are wavelength multiplexed in a single optical fiber that can be several kilometers long. The signals are then detected with a spectrum analyzer and related to the temperature, pressure, and index of refraction at the measurement site. The light sources for the sensors and the optical fiber are located in a probe vehicle or distributed along the detector return fiber and are inexpensive enough to be expendable.
It is, therefore, a primary object of this invention to provide improvements in the optical sensing of temperature, pressure, and index of refraction wherein the operation is drift free.
Another object of this invention is to provide an improved method for sensing temperature, pressure, and the index of refraction in inaccessible locations and at small scales, wherein the sensors are expendable.
Another object of this invention is to provide an improved method for sensing temperature, pressure, and the index of refraction in an electrically conducting fluid or in the presence of an electromagnetic field.
These and other objects and features of the present invention will become more fully apparent from the following description and appended claims taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic plan view of one presently preferred wavelength multiplexed embodiment of the multiple sensor instrument of this invention,
FIG. 2 is a graphical comparison between the 10 spectral intensities and the wavelength for three light sources and the spectrograph detector output of FIG. 4,
FIG. 3 is a schematic plan view of a second preferred time multiplexed embodiment of the multiple sensor instrument of this invention, and
FIG. 4 is a schematic plan view of one presently preferred expendable embodiment of the probe and spectrograph of this invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
This invention is best understood by reference to the drawings wherein like parts are designated with like numerals throughout.
In order to avoid the drift associated with present optical sensors it is desirable to have the sensed quantity modulate the wavelength of an optical signal rather than its amplitude; a wavelength resolving detector also allows the wavelength multiplexing of many signals into a single optical fiber. Such a combination is presented in FIG. 1, wherein is shown a schematic of one preferred embodiment of this invention. Individual broad band radiant energy sources 5, 6, and 7 have band widths that are separate from each other and are particularly chosen for the sensors 21, 22, and 23 they are coupled to. The radiant energy path means consists of first optical fiber waveguides 9, 10, and 11 coupling each radiant energy source to each sensor. The first optical fiber waveguide may be a single mode fiber, as for instance in the case of a refraction sensor. The second optical fiber waveguides 15, 16, and 17 couple the sensors to the wavelength division multiplexer 27, and a third optical fiber waveguide means 29 couples the wavelength division multiplexer 27 and all of the sensor signals to the spectrograph detector 30.
The sensing means are radiant energy filters whose band edges occur at different wavelengths from each other and are functions of many parameters, such as the temperature, pressure, and index of refraction external to the sensor. The sensors provide a direct or reflective path from said first waveguide means, through said sensing means, to said second waveguide means. The radiant energy sources and their emission bandwidth are particularly chosen to cover the expected range of variation of the sensor band edge over its sensed parameter range. An illustrative example of this is presented in FIG. 2, wherein the dotted lines represent the spectral intensities of the radiation sources and the solid lines are for the band edge sensors. Finally, the detecting means 30 is optically coupled to the third optical fiber waveguide means 29; with a dispersing prism and/or a diffraction grating the signal is dispersed by the detector in an angular manner in space according to wavelength, said spectral intensities then being detected with suitable photodetectors, such as charge-coupled devices or charge-injection devices. The detector microprocessor then correlates the spectral intensities, and the resulting wavelength of the band edges, with the parameters each band edge is intended to measure. With the present detector technology, wavelengths from 400 nanometers (nm) to 1100 nm can be measured. This would be adequate for a temperature, pressure, and index of refraction sensor combination or for six or more individual temperature sensors using different materials such as Selenium, Gallium Arsenide, and Indium Phosphide.
In the general case, to combine more than three sensors into the instrument described herein the technique of time division multiplexing must be used in place of or in addition to wavelength division multiplexing. With the detector remote from the sensors the third waveguide means coupling them is alternately used by the various sensors; with optical fiber the switching between the various sensors can be done very quickly permitting the use of 300 sensors instead of the usual two or three for thin electrical wire. Referring to FIG. 3, wherein this technique is best shown, we see that a single broad-band radiant energy source 8 is used, said source having a band width sufficient to cover 15 the range of the band edges of sensors 21-26. Radiant energy source 8 is optically coupled by the first optical fiber waveguides 9-14 to the sensing means 21-26 and thence to the time division multiplexer 28 via second optical fiber waveguides 15-20. The time division multiplexer alternately couples the sensing means 21 through 26 to the spectrograph detector 31 via the third optical fiber waveguide means 29. The first optical fiber waveguide means 9-14 can be single mode fiber, as for instance with a refraction sensor, and the sensing means can be distributed over an area or distance and in this embodiment can be comprised of many temperature sensors of the same material and band edges. Further, as the sensors are generally composed of a small 45° -90° -45° prismatic material just big enough to sit upon two optical fibers, the outer dimension of each sensor is that of two optical fibers, or 0.6 mm, and can be used in very restricted regions.
The limitation on the number of sensors in the wavelength division multiplexed method of FIG. 1 is imposed by the spectral characteristics of the silicon photodetectors. Use of the newly developed Indium Antinimide (InSb) charge-injection devices or the Platinum Silicide (PtSi) charge-coupled devices will extend the wavelength range out to 3,000 nm and allow many more than three sensors in the embodiment of FIG. 1.
As was mentioned before, the present electrical expendable oceanographic sensors and transmission lines are subject to shorting out in sea water and have a very limited data rate and, therefore, a limited number and type of sensing capabilities and sampling rates. Optical sensors and transmission lines avoid this problem as can be shown by considering FIGS. 1 and 2. We contain the sensing means 21-26 within a probe vehicle; the long third optical fiber waveguide means 29 is also contained within said probe vehicle on a reel. Said third optical fiber waveguide means is further capable of being unreeled during a moving measurement process and then severed upon completion of that mesurement process. Such an application could be from an oceanographic research vessel in which said probe vehicle is dropped over the side of said vessel thereby measuring many parameters during its descent. The optical fiber waveguide 29 upon being fully unreeled is severed simply by the motion of said probe vehicle. The radiant energy sources, the first, second, and third optical fiber waveguide means and multiplexer, and the sensing means are thereby expended along with the probe vehicle.
Up until recently, the cost of optical fiber has prevented its use in expendable instruments; it is presently five to six times the cost of expendable wire. However, optical fiber expendables will become cost competitive and then cheaper than electrical expendables due to three emerging factors: the cost of optical fiber has diminished by a factor of 10 in the last 8 years and Corning Glass Works has stated that it desires to make fiber equivalent to wire in price; the volume usage if optical fiber replaces wire in expendable oceanographic instruments would double the present total annual optical fiber production in the U.S.; and the strength, bandwidth and attenuation requirements of expendable fiber are significantly less than those for telecommunications optical fiber.
An oceanographic configuration of immediate use for the first preferred embodiment of this invention is best shown in FIG. 4. We have a probe vehicle containing temperature, pressure, and index of refraction sensors coupled to optical fiber reeled upon a drum and then connected to a remote spectrograph detector. The probe vehicle 35 has a weighted Zinc forebody 37, plastic afterbody 38, and a stabilizing ring 39. A 3/8" flushing hole 36 extends from the nose along the center line to the tail, within which is located the temperature sensor 22 and the index of refraction pressure sensor and diaphram 21 is located in at the skin of the probe vehicle between afterbody where the radius of curvature zero. The light emitting diodes (LEDs) light sources and batteries 5-7 are coupled to the sensors 21-23 by the first optical fiber waveguide means 9-11, and the sensors are coupled to the wavelength multiplexer 27 by the second optical fiber waveguide means 15-17. The third optical fiber waveguide means 29 couples the wavelength multiplexer with the spectrograph detector 30 and is coiled around reel 40 in the probe vehicle and reel 41 near the spectrograph detector 30. The detector 30 is located remotely, as for example on board an oceanographic vessel, and is comprised of a glass or rutile dispersing prism 32, a line scan photo detector camera 33, and a microprocessor 34. The diameter of the probe vehicle is approximately 3/4" and its length is required to be greater than 11" to avoid resonant instabilities during its free-fall.
The temperature sensor 22 is a selenium prism whose absorption/transmission band edge goes from 725 nm to 755 nm as the temperature goes from 0° C. to 30° C.; this requires red LEDs as light source 6. The pressure sensor 21 is a birefringent crystal or other photoelastic material, such as quartz or glass, whose output displays maximums and minimums in intensity as function of the wavelength of radiation and the applied pressure. The wavelength shift of the maximum/minimum band edge is about 60 nm as the pressure goes from atmospheric to that at 1000 meters depth in the ocean; this requires LEDs of the Gallium Aluminum Arsenide class in the 900 nm to 1100 nm emission range. The index of refraction sensor 23 is a glass retroreflecting prism whose sensing face forms an interface between the glass prism and the seawater. The sensing face is at the nominal critical angle for the incident radiant energy; the wavelength of the reflection/transmission band edge is measured and is a function of the seawater index of refraction. See my co-filed patent application, Seaver "REFRACTION SENSOR", filed on Apr. 3, 1985, Ser. No. 719,399 (U.S. Pat. No 4,699,511. As the radiant energy incident to the sensing face must be collimated, the light source 7 is coupled to the sensor 23 with a single mode fiber 11. A seawater index of refraction change of 0.0096 represents a shift in the reflection band edge from 400 nm to 700 nm and requires green-blue LEDs. FIG. 2 shows the spectral intensity outputs for the above described light sources (dotted lines) and sensors (solid lines).
The method for measuring the temperature, pressure, and index of refraction of a vertical section of the ocean with the above described instrument is to first deploy the probe into the ocean, as from a vessel on or in it. The gravity induced free-fall begins to unreel the optical fiber waveguide 29 contained with the probe vehicle, the sensed signal is conveyed back to the spectrograph detector, and the measurement begins. Values of pressure (which can be readily converted to depth,) temperature, and index of refraction are continuously recorded as the probe vehicle descends through the ocean. When the optical fiber waveguide 29 is completely unreeled from drum 40, the weight and motion of the probe nose 37 causes the optical fiber waveguide 29 to sever and the measurement is complete. Motion of the surface vessel is compensated for by also unreeling optical fiber waveguide 29 from drum 41 on board the ship during the measurement. Customarily the total time and depth of the measurement is 70 to 300 seconds and 500 meters to 2000 meters, respectively.
It is obvious that minor changes may be made in the form and construction of the afore described invention without departing from the material spirit thereof. It is not, however, desired to confine the invention to the exact form herein shown and described, but it is desired to include all such as properly come within the scope claimed. | Present electrical expendable oceanographic instruments are vulnerable to insulation leaks and electromagnetic interference; they are also unable to measure pressure and the index of refraction. In response to these difficulties a unique combination of optical temperature, pressure, and index of refraction sensors have been developed. These sensors are coupled to an optical fiber transmission link which is contained initially within a probe vehicle and is designed to be unreeled. The remote sensing feature of this combination and technique makes the instrument also suitable for industrial and data - and tele-communications use. The principle of the three sensors is that of optical filters, whose band edges are functions of temperature, pressure, and the index of refraction; this wavelength modulation technique avoids drift and allows the signals from the sensors to be wavelength multiplexed in a single optical fiber, and to be read remotely by a single detector. | 6 |
This application is a continuation of application Ser. No. 08/241,926, filed May 12, 1994, now abandoned which is a continuation of Ser. No. 08/066,454 filed May 24, 1993 now abandoned.
BACKGROUND OF THE INVENTION
This invention relates to the use of modified polyisocyanates as crosslinking agents for binders used in textile printing pastes.
Non-self-crosslinking film-forming binders, for example, those based on polyacrylates or butadiene/acrylonitrile copolymers, are widely used in the textile printing industry. The mixtures of binder and pigment normality contain additionally reactive compounds which, after printing, crosslink the binder at a relatively high temperature and are thus able to fix the print. It is only this fixing that leads to the required water resistance that is important, for example, in washing the printed textiles. (The term "pigments" in the context of the invention also includes dyes.)
In practice, melamine/formaldehyde condensates which enter into crosslinking reactions only at temperatures above about 120° C. are most commonly used as crosslinking agents for the binders used in textile printing pastes. According to W. Berlenbach in Ullmanns Encyklop adie der technischen Chemie, 4th Edition, Vol. 22, page 629, Verlag Chemie, Weinheim 1982, crosslinking is catalyzed by acids via N-methylol groups in the binder. The print is best fixed by exposure to dry hot air, for example, for 5 to 10 minutes at 140° C. or for 30 to 60 seconds at 175° C.
German Offenlegungsschrift 3,529,530 proposes textile printing pastes that contain separately crosslinkable binders dispersed in water or in organic solvents and "deactivated" (i.e. partly blocked) polyisocyanates as crosslinking agents.
German Offenlegungsschrift 3,109,978 describes water-based textile printing pastes that contain film-forming separately crosslinkable polymers as binders and isocyanate prepolymers as crosslinking agents. By comparison with low molecular weight polyisocyanates, these prepolymers apparently provide the printing pastes with a longer pot life by virtue of their higher molecular weights and their lower content of reactive groups.
German Offenlegungsschrift 3,836,030 describes coating compositions that are suitable for the preparation of coatings permeable to water vapor on leather and textiles by the method of evaporation coagulation. In addition to thickeners, these coating compositions contain carboxylate- and/or sulfonate- and/or polyethylene oxide-modified (and hence "hydrophilicized") polyurethanes in aqueous dispersion, high-boiling organic solvents as "non-solvents" for the polyurethanes dispersed in water, NCO-free crosslinking agents, and hydrophilic polyisocyanates to promote coupling with the substrate and as crosslinking agents for the dispersed polyurethanes. During the evaporation process, the non-solvent leaves micropores in the polyurethane film remaining behind and thus guarantees the desired permeability of the coating to water vapor.
German Offenlegungsschrift 3,512,918 relates to hydrophilic isocyanate derivatives containing carbodiimide groups and to their use as crosslinking agents for polymers present in aqueous solution or dispersion that are said to be suitable inter alia for the coating of textiles. Printing pastes are not mentioned.
British Patent 962,109 discloses coating compositions based on special copolymers that are crosslinked with diepoxides. The disclosed compositions may also be used for the preparation of printing pastes. However, the printing pastes in question are not entirely satisfactory in regard to the reactivity and fastness values of prints produced using them.
The disclosed textile printing pastes of the prior art are attended by various disadvantages. Either formaldehyde is given off during the crosslinking reaction and also subsequently in the use of the printed textiles, which is particularly undesirable, or the number of reactive groups available for the crosslinking reaction is difficult to control or the crosslinking agent can be dispersed only with some effort. In addition, known printing pastes generally do not give satisfactory fastness values when heat-treated at temperatures below 100° C. Accordingly, the problem addressed by the present invention was to provide textile printing pastes which would not have any of these disadvantages.
It has now surprisingly been found that this problem can be solved by the use of special mixtures of hydrophilicized polyisocyanates, which give prints having excellent fastness values.
SUMMARY OF THE INVENTION
Accordingly, the present invention relates to a textile printing paste comprising a pigment, a binder, and a crosslinking agent, wherein said crosslinking agent is
I) a polyisocyanate mixture prepared by reaction at an NCO:OH equivalent ratio of at least 2:1 of (A) a polyisocyanate component having an (average) NCO functionality of 2.1 to 4.4 in which at least one polyisocyanate of said polyisocyanate component contains only (cyclo)aliphatically bound isocyanate groups with (B) a polyalkylene oxide polyether alcohol containing a statistical average of 5 to 70 ethylene oxide units, wherein said polyisocyanate mixture (I) has
(i) an average NCO functionality of 1.8 to 4.2,
(ii) a content of (cyclo)aliphatically bound isocyanate groups (expressed as NCO, molecular weight 42) in the range from 12.0 to 21.5% by weight, and
(iii) a content of ethylene oxide units (expressed as C 2 H 4 O, molecular weight 44) arranged within polyether
chains of 2 to 20% by weight; or
II) an isocyanate derivative prepared from an organic polyisocyanate having an (average) NCO functionality of 2.0 to 2.5 or a mixture of organic poly- and monoisocyanates having an average NCO functionality of 1.3 to 2.5 and, optionally, compounds containing isocyanate-reactive groups, wherein said isocyanate derivative contains
(i) 2 to 30% by weight (preferably 5 to 15% by weight) of carbodiimide groups --N═C═N--, with the statistical average being 0.8 to 30 (preferably 1 to 25 and more preferably 1.2 to 20) --N═C═N-- groups per molecule,
(ii) 5 to 200 (preferably 5 to 150 and more preferably 5 to 120) milliequivalents of chemically incorporated sulfonate groups per 100 g of isocyanate derivatives (II), and
(iii) optionally (and preferably), 0 to 25% by weight (preferably 0 to 20% by weight and more preferably 0 to 15% by weight), based on isocyanate derivatives (II), of chemically incorporated ethylene oxide units --CH 2 --CH 2 --O-- positioned within polyether chains; or
III) bisglycidyl-2,2-diphenylpropane or a polyepoxide containing at least three epoxide groups per molecule.
The present invention further relates to a method comprising printing a textile with said textile printing paste.
DETAILED DESCRIPTION OF THE INVENTION
The polyisocyanate mixtures (I) to be used in accordance with the invention generally have a viscosity of 50 to 10,000 mPa•s at 23° C. These polyisocyanate mixtures can be prepared in known manner by reaction of a polyisocyanate component (A) having an (average) NCO functionality of 2.1 to 4.4 (preferably 2.3 to 4.3) and comprising at least one polyisocyanate containing only (cyclo)aliphatically bound isocyanate groups with a monohydric or polyhydric polyalkylene oxide polyether alcohol (B) containing a statistical average of 5 to 70 ethylene oxide units, an NCO:OH equivalent ratio of at least 2:1 (generally 4:1 to approximately 100:1) being maintained during the reaction and the type and quantities of the starting components mentioned being selected so that the resulting reaction products correspond to the conditions mentioned above under (I)(i) to (I)(iii).
Polyisocyanate component (A) encompasses uretdione, isocyanurate, urethane allophanate, biuret, and/or oxadiazine polyisocyanates produced by modification of simple (cyclo)aliphatic diisocyanates, such as are described, for example, in German Offenlegungsschriften 1,670,666, 3,700,209, and 3,900,053 or in European Patent Applications 336,205 and 39,396. Polyisocyanate components (A) containing less than 1% by weight (preferably less than 0.5% by weight) monomeric isocyanate are particularly preferred.
Suitable diisocyanates for the preparation of these polyisocyanates (A) are, basically, those having a molecular weight in the range from 140 to 400 and containing (cyclo)aliphatically bound isocyanate groups, such as 1,4-diisocyanatobutane, 1,6-diisocyanatohexane, 1,5-diisocyanato-2,2-dimethylpentane, 2,2,4- and 2,4,4-trimethyl-1,6-diisocyanatohexane, 1,10-diisocyanatodecane, 1,3- and 1,4-diisocyanatocyclohexane, 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane (i.e., isophorone diisocyanate) and 4,4'-diisocyanatodicyclohexylmethane or mixtures of these diisocyanates.
The polyisocyanate component (A) is preferably an isocyanurate-modified and, optionally, uretdione-modified polyisocyanate mixture consisting essentially of trimeric 1,6-diisocyanatohexane and, optionally, dimeric 1,6-diisocyanatohexane with an NCO content of 19 to 24% by weight. In a particularly preferred embodiment, component (A) is selected from the corresponding isocyanurate-modified polyisocyanates with the same NCO content, but substantially free from uretdione groups, that are obtained in known manner by catalytic trimerization of 1,6-diisocyanatohexane with isocyanurate formation and which preferably have an (average) NCO functionality of 3.2 to 4.2.
Component (B) is selected from monohydric or polyhydric polyalkylene oxide polyether alcohols which, on a statistical average, contain 5 to 70 (preferably 6 to 60) ethylene oxide units per molecule and which can be obtained in known manner by alkoxylation of suitable starter molecules. The starter molecules used for the preparation of the polyether alcohols (B) may be any monohydric or polyhydric alcohols having a molecular weight in the range from 32 to 150, the use of which is described, for example, in European Patent Application 205,059. Preferred starter molecules are mono-functional aliphatic alcohols containing 1 to 4 carbon atoms, with methanol, ethanol, propanol, and butanol being particularly preferred. Alkylene oxides suitable for the alkoxylation reaction are preferably ethylene oxide and propylene oxide, which may be used in any order or even in admixture in the alkoxylation reaction.
The polyalkylene oxide polyether alcohols (B) are either pure polyethylene oxide polyethers or mixed polyalkylene oxide polyethers that contain at least one polyether chain containing at least 5 (generally 5 to 70, preferably 6 to 60 and, more preferably, 7 to 20) ethylene oxide units and in which at least 60 mol-% (preferably at least 70 mol-%) of the alkylene oxide units are ethylene oxide units.
Preferred polyether alcohols (B) for the preparation of the polyisocyanate mixtures to be used in accordance with the invention are monofunctional polyalkylene oxide polyethers containing a statistical average of 6 to 60 ethylene oxide units that have been initiated with an aliphatic alcohol containing from I to 4 carbon atoms. Particularly preferred polyether alcohols (B) are pure polyethylene glycol monomethyl ether alcohols containing a statistical average of 7 to 20 ethylene oxide units.
Instead of the preferably nonionically/hydrophilically modified polyisocyanates described above, unmodified polyisocyanates of the type mentioned above by way of example as component (A) may also be used as the source of all or part of the (cyclo)aliphatically bound isocyanate groups described in (I)(ii), with the proviso that the polyisocyanates are used in combination with suitable emulsifiers, for example, those described, European Patent Application 13,112 for the hydrophilicization of aromatic polyisocyanates.
Suitable binders which may be crosslinked with the polyisocyanate mixtures to be used in accordance with the invention include, for example, polymers such as polymers based on natural or synthetic rubber, styrene/butadiene copolymers, polymers of 2-chlorobutadiene, styrene/acrylonitrile copolymers, polyethylene, chlorosulfonated or chlorinated polyethylene, butadiene/acrylonitrile copolymers, butadiene/methacrylate copolymers, polyacrylates, PVC or optionally partly saponified ethylene/vinyl acetate copolymers, or polyaddition compounds, such as those based on polyurethanes, that is, products of the type described, for example, in Ullmanns Encyklop aidie der technischen Chemie, 4th Edition, Vol. 16, Verlag Chemie, Weinheim/New York 1978, pages 159 et seq. and the literature references cited therein or in German Offenlegungsschriften 1,953,345, 1,953,348, or 1,953,349 or in U.S. Pat. No. 2,939,013.
The crosslinking agent to be used in accordance with the invention is generally used in a quantity of 1 to 25 parts by weight (preferably 2.5 to 12.5 parts by weight) per 100 parts by weight of binder. This selection of the quantity of crosslinking agent presupposes that the binder contains at least the number of NCO-reactive groups (preferably hydroxyl groups) necessary to allow the isocyanate groups of the crosslinking agent (I) to react completely at the latest during fixing.
Because NCO-functional crosslinking agents are capable of reacting with every possible Zerewitinoff-active hydrogen atom (not just hydroxyl groups), the polymers on which the binders are based need not contain hydroxyl groups. Carboxyl, urethane, urea, amine, amide groups, and the like (see Saunders and Frisch, Polyurethanes, Part 1, Interscience Publishers, New York 1962, pages 63 et seq.) are also accessible to a crosslinking reaction. In the crosslinking reaction, it is generally not necessary--and in many cases not even desirable--to allow all the crosslinkable groups to react with isocyanates. In general, the crosslinking effect is merely phenomenologically determined. A certain resistance to water, abrasion, and the like are generally achieved with the above-mentioned 1 to 25 parts by weight of crosslinking agent per 100 parts by weight of binder without any significantly adverse affect on the elastic properties.
The binders to be used for the printing pastes are preferably free from perfluoroalkyl groups.
The crosslinking agents (II) to be used in accordance with the invention are known, for example, from German Offenlegungsschrift 3,512,918. Starting materials for the preparation of crosslinking agents (II) are (a) organic polyisocyanates having an (average) NCO functionality of 2.0 to 2.5 or mixtures of organic poly- and monoisocyanates having an average NCO functionality of 1.3 to 2.5 and, optionally, (b) compounds containing isocyanate-reactive groups and having a functionality of 1 or more in the context of the isocyanate addition reaction. Either or both of starting materials (a) and (b) can be compounds containing the sulfonate groups.
The synthesis components (a) include aliphatic, cycloaliphatic, araliphatic, aromatic or heterocyclic polyisocyanates (a1) of the type described, for example, by W. Siefken in Justus Liebigs Annalen der Chemie, 562, pages 75 to 136. Preferred polyisocyanates al) of this type include, for example, the commercially readily obtainable diisocyanates, such as hexamethylene diisocyanate, 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane and, preferably, aromatic diisocyanates, such as 2,4- and, optionally, 2,6-diisocyanatotoluene or 4,4'- and, optionally, 2,4'-diisocyanatodiphenylmethane, 3,4'-diisocyanato-4-methyldiphenylmethane, or 3,2'-diisocyanato-4-methyldiphenylmethane, and isomers thereof or mixtures of these diisocyanates. However, particularly preferred diisocyanates are phenylene diisocyanates sterically hindered by alkyl substituents, such as 1-methyl-3,5-diethyl-2,4-diisocyanatobenzene, 1-methyl-3,5-diethyl-2,6-diisocyanatobenzene, and mixtures of these two diisocyanates, 1,3,5-triisopropyl-2,4-diisocyanatobenzene or alkyl-substituted phenylene diisocyanates of the type described by way of example in U.S. Pat. No. 3,05,845 or German Offenlegungsschrift 3,317,649.
Other starting materials (a) include, for example, hydrophilically modified polyisocyanates (a2). Suitable such polyisocyanates include both polyisocyanates containing sulfonate groups or groups convertible into sulfonate groups by a neutralization reaction, for example, of the type described in U.S. Pat. No. 3,959,329, and mono- or diisocyanates containing ethylene oxide units positioned within polyether chains of the type described in German OffenlegungsSchrtften 2,314,512, 2,314,513, 2,551,094, and 2 651 506, and U.S. Pat. Nos. 3,920,598 and 3,905,929. A sulfonated diisocyanate obtained by reaction of 2,4-diisocyanatotoluene with equimolar quantities of chlorosulfonic acid at room temperature in the presence of solvents such as 1,2-dichloroethane is also suitable as a compound containing groups convertible into sulfonate groups by reaction with neutralizing agents, such as triethylamine. Where compounds such as these are used as component (a2), neutralization is carried out after the reaction.
However, particularly preferred hydrophilically modified polyisocyanates are NCO prepolymers obtained by reaction of excess quantities of the diisocyanates mentioned by way of example under (a1) (especially the particularly preferred sterically hindered phenylene diisocyanates) with diols containing sulfonate groups. In the preparation of these NCO prepolymers, the starting materials are generally reacted at 20° to 150° C. in an NCO:OH equivalent ratio of 1.2:1 to 10:1. Diols containing sulfonate groups suitable for the preparation of the NCO prepolymers are preferably those corresponding to the following general formula: ##STR1## in which A and B independently represent difunctional aliphatic hydrocarbon groups containing 1 to 6 carbon atoms,
R represents hydrogen, an aliphatic hydrocarbon group containing 1 to 4 carbon atoms, or a phenyl group,
M + represents an alkali metal cation or an optionally substituted ammonium group,
n and m independently represent numbers of from 0 to 30,
o and p independently have a value of 0 or 1, and
q is an integer of from 0 to 2.
The preparation of these sulfonate diols is described, for example, in German Auslegeschrift 2,446,440 and U.S. Pat. No. 4,108,814. Particularly preferred sulfonate diols are those in which m and n may be the same or different and represent numbers of from 0 to 3.
Further starting materials (a) include, for example, organic monoisocyanates (a3), such as hexyl isocyanate, phenyl isocyanate, or p-toluene isocyanate. As mentioned above, however, these monoisocyanates are used in admixture with organic polyisocyanates of the type mentioned above by way of example, with the mixture having an average NCO functionality of 1.3 to 2.5 (preferably 1.3 to 2).
In addition, component (a) may also contain other modified polyisocyanates, such as reaction products of excess quantities of organic diisocyanates of the type mentioned by way of example under (a1) with di- or trihydroxyalkanes having a molecular weight below 400 (such as ethylene glycol, propylene glycol, tetramethylenediol, hexamethylenediol, trimethylol propane, and/or glycerol).
The optional synthesis components (b) for the preparation of crosslinking agents (II) include, for example, polyhydric (preferably dihydric) alcohols (b1) having a molecular weight below 400, such as ethylene glycol, propylene glycol, tetramethylenediol, hexamethylenediol, octamethylenediol, neopentyl glycol, 2-methyl-1,3-dihydroxypropane, glycerol, trimethylol propane, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycols having molecular weights in the range mentioned above, dipropylene glycol, tripropylene glycol, or mixtures of these polyhydric alcohols.
Other optional synthesis components (b) include, for example, polyfunctional (preferably difunctional) amines (b2) having a molecular weight below 400 and containing at least two primary and/or secondary amino groups, such as 1,2-diaminoethane, hexamethylenediamine, piperazine, 1-amino-3-amino-methyl -3,5,5-trimethylcyclohexane, 4,4'-diaminodicyclohexyl methane, or mixtures of these amines. The use of amines such as these is, however, less preferred than hydroxyfunctional components (b).
Other optional synthesis components (b) include, for example, hydrophilically modified monohydric or dihydric alcohols (b3), such as the sulfonate diols mentioned by way of example above under (a2) or even compounds containing ethylene oxide units corresponding to the following general formula ##STR2## in which R is a difunctional substituent of the type obtained by formal removal of the isocyanate groups from a diisocyanate R(NCO) 2 of the type mentioned above under (a1),
R' represents hydrogen or a monofunctional hydrocarbon group containing 1 to 8 carbon atoms (preferably hydrogen or methyl),
R" is a monofunctional hydrocarbon group containing 1 to 12 carbon atoms (preferably an unsubstituted alkyl group containing 1 to 4 carbon atoms),
X is a polyalkylene oxide chain containing 5 to 90 (preferably 20 to 70) chain segments, of which at least 40% (preferably at least 65%) consist of ethylene oxide units and which, in addition to ethylene oxide units, may also contain propylene oxide, butylene oxide, or styrene oxide units (preferably propylene oxide units), and
Y and Z independently represent oxygen or --NR'"--, where R'" has the same definition as R".
The crosslinking agent (II) corresponding to the above formulas can be prepared by the methods described in German Offenlegungsschriften 2,314,512 and 2,314,513. In addition to the disclosures of those documents, it is also possible to use, instead of the monofunctional polyether alcohols mentioned therein as starting material, monofunctional polyether alcohols in which the polyether segment may also contain up to 60% by weight, based on polyether segment, of propylene oxide, butylene oxide, or styrene oxide units (preferably propylene oxide units) in addition to ethylene oxide units. The presence of "mixed polyether segments" such as these can sometimes afford specific advantages.
The hydrophilic monohydric alcohols suitable for use in accordance with the invention include, for example, compounds corresponding to the following formula:
H--X--Y--R"
in which X, Y and R" have the definitions given above under (b3). These monohydric, hydrophilically modified alcohols can be prepared by the methods described in U.S. Pat. Nos. 3,905,929 or 3,920,538, for example, by alkoxylation of suitable starter molecules (such as butanol, for example) with ethylene oxide and, optionally, other alkylene oxides (such as propylene oxide, for example).
Other optional synthesis components (b) include, for example, aminosulfonates (b4), preferably diaminosulfonates of the type described in Canadian Patent 928,323, such as, preferably, the sodium salt of N-(2-aminoethyl)-2-aminoethanesulfonic acid.
Other optional starting components (b) include, for example, monohydric alcohols or monofunctional primary or secondary amines (b5) having a molecular weight below 400, including, for example, methanol, ethanol, butanol, i-butanol, octanol, or dodecanol and methyl amine, ethyl amine, hexyl amine, or aniline. These monohydric components are often used as chain-extending agents.
Other optional synthesis components (b) include hydrazine, hydrazine hydrate, or hydrazine derivatives, such as carboxylic acid hydrazides or semicarbazides. Ammonia may also be used as synthesis component (b) and acts as a particularly suitable chain terminator.
Preferred polyepoxides (III) are polyepoxides, such as bisglycidyl-2,2-diphenylpropane, triglycidyl urazole, and the like. The most preferred polyepoxide (III) is triglycidyl isocyanurate.
The foregoing observations in respect of the ratio of crosslinker (I) to binder also apply to the ratio of crosslinker (II) or crosslinker (III) to binder.
Crosslinking agents (I) are most particularly preferred.
The pigments suitable for the textile printing pastes are virtually free from limitations and can be inorganic or organic. Suitable organic pigments include, for example, those of the azo, anthraquinone, azoporphine, thioindigo, dioxazine, naphthalene tetracarboxylic acid, or perylene tetracarboxylic acid series, and lacquered dyes, such as calcium, magnesium, or aluminum lacquers of dyes containing sulfonic acid and/or carboxylic acid groups, of which a large number are known, for example, from Colour Index, 2nd Edition. Suitable inorganic pigments include, for example, zinc sulfides, titanium dioxides, ultramarines, iron oxides, nickel and chromium compounds, carbon blacks, silicon dioxides, and aluminum oxides.
The quantity of pigment used in the textile printing pastes is generally from 0.5 to 50% by weight (preferably from 5 to 35% by weight), based on the sum of binder, crosslinker, and pigment.
The binders and crosslinking agents can be dispersed as usual in water, optionally using organic solvents, for example, as in the so-called "petrol emulsion process", in which oil-in-water emulsions are formed. For reasons of ecological compatibility, however, it is preferred to use petrol-free printing pastes. In establishing the formulation, it is best to leave out components containing reactive groups that could interfere with the reaction between binder and crosslinking agent.
Other auxiliaries, such as emulsifiers, thickeners, evaporation inhibitors, catalysts, feel-promoting agents, antifoam agents, can, of course, be used in the preparation of the printing pastes.
The textile printing pastes can be processed by conventional printing techniques. See, for example, Ullmanns Encyklopadie der technischen Chemie, 4th Edition, Vol. 22, pages 565 et seq., "Textildruck", Verlag Chemie, Weinheim 1982.
The applied printings may be crosslinked at elevated temperatures. The crosslinking agents to be used in accordance with the invention enable relatively low temperatures (for example, in the range from 80° to 100° C.) to be applied, although higher temperatures of up to 170° C. are not harmful. In most cases, however, excellent results can be obtained using curing conditions of 80° to 100° C. for 1 to 10 minutes. Ultimate strength can also be achieved by drying for prolonged periods (e.g., 1 to 3 days) at room temperature.
In a particular embodiment of the invention these crosslinking agents can also be used together with binders and pigments for the dyeing of textiles in aqueous media. The wet and dry rub resistance is also improved by the use of the hydrophilicized isocyanates as crosslinking agents.
The following examples further illustrate details for this invention. The invention, which is set forth in the foregoing disclosure, is not to be limited either in spirit or scope by these example. Those skilled in the art will readily understand that known variations of the conditions of the following procedures can be used. Unless otherwise noted, all temperatures are degrees Celsius and all parts and percentages are parts by weight and percentages by weight, respectively.
EXAMPLES
The following components were used in the examples:
Acrylate binder:
40% aqueous dispersion of an acrylonitrile/butyl acrylate/styrene/acrylic acid emulsion copolymer (4:83:8:3 parts)
Polyurethane binder:
40% aqueous dispersion of a polyurethane (a sulfonate groups containing polyester polyurethane based on hexamethylene diisocyanate; Acramin® PUD, Bayer AG, Germany)
Thickener solution:
4% aqueous solution of a cellulose derivative (Natrosol® MR, Hercules Powder)
Emulsifier L:
42% aqueous emulsifier solution (Emulgator L, Bayer AG, Germany)
Emulsifier VA:
46% aqueous emulsifier solution (F, mulgator VA, Bayer AG, Germany)
Emulsifier WN:
90% aqueous solution of an ethylene oxide polyether initiated with a phenolic component and having an average molecular weight of the order of 900 (F, mulgator WN, Bayer AG, Germany)
Acrylic acid/acrylamide copolymer dispersion:
29% dispersion of the ammonium salt of a weakly crosslinked hydrocarbon (Acraconz® BN, Bayer AG, Germany)
Acramin Navyblue FBC:
aqueous pigment formulation based on copper phthalocyanine (Acramin® Marineblau FBC, Bayer AG, Germany) Solvesso 100: aromatic hydrocarbon mixture (bp 163°-181° C.) (Esso Chemie, Cologne, Germany)
Melamine/formaldehyde condensate: Acrafix® MF (Bayer AG, Germany)
Polyisocyanate 1
40 g of a 3-ethyl-3-hydroxymethyloxetane-initiated monofunctional ethylene oxide polyether (molecular weight 1210) were added with stirring to 500 g of a 1,6-diisocyanatohexane trimer consisting essentially of tris(6-isocyanatohexyl)isocyanurate and higher homologs thereof (NCO content 21.6%, average NCO functionality 3.3, monomeric diisocyanate content below 0.3%, viscosity mPa.s/23° C.). After the mixture was stirred for 2 hours at 100° C., a polyisocyanurate preparation having an NCO content of 19.7% by weight and a viscosity of 3200 mPa.s/23° C. was obtained. This preparation corresponds to the composition of Example 3 of European Patent Application 206,059.
Polyisocyanate 2
80.8 g of a butanol-initiated monofunctional ethylene oxide polyether (molecular weight 1145) heated to 50° C. were added with stirring to 1000 g of a 1,6-diisocyanatohexane trimer consisting essentially of tris(6-isocyanatohexyl)isocyanurate and higher homologs thereof (NCO content 21.6%, average functionality 3.3, monomeric diisocyanate content below 0.3%, viscosity 1700 mPa.s/23° C.). After the mixture was stirred for 2.5 hours at 110° C., a clear resin having an NCO content of 18.4% and a viscosity of 2500 mPa.s/23° C. is obtained.
Polyisocyanate 3
0.08 val (mol OH) of a methanol-initiated monofunctional ethylene oxide polyether (average molecular weight 350) were added with stirring at room temperature to 1.0 val (mol NCO) of an isocyanurate-modified polyisocyanate based on 1,6-diisocyanatohexane having an NCO content of 1.5%, an average NCO functionality of approximately 3.8 and a viscosity of 3000 mPa.s (23° C.), followed by heating for 3 hours to 100° C. A substantially colorless clear polyisocyanate mixture was obtained after cooling to room temperature and had an NCO content of 17.3%, a content of ethylene oxide units of 11.3%, and a viscosity of 3050 mPa.s (23° C.).
Polyisocyanate 4
1000 g of the isocyanurate of isophorone diisocyanate in the form of a 50% solution in a solvent mixture (methoxypropyl acetate/Solvesso 100 at a ratio of 1.6:1 parts by weight) were reacted with 50 g of 3-ethyl-2hydroxymethyloxetane polyglycol ether (molecular weight 1210) in the same way as for Polyisocyanate 1 to form a hydrophilicized isocyanate having an isocyanate content of 6.1%.
Comparison 1: Oil-in-water emulsion print
An emulsion was prepared from 225 g of water, 40 g of thickener solution, 25 g of a 33% aqueous solution of diammonium phosphate, 10 g of Emulsifier L, and 700 g of white spirit. 120 g acrylate binder, 30 g of Acramin Navyblue FBC, and 10 g of reelamine/formaldehyde condensate were then added to 840 g of the emulsion. A cotton fabric and a cotton/polyester fabric were then printed with the printing paste obtained (flat-bed printing). The print was fixed for 2 minutes at 80° C.
Internal testing method
Brush-washing test
Fixation of ACRAMIN dyeings can be checked by the brush-washing test, since there is not really any other way of determining the degree of crosslinking of the binder.
Take a specimen (approx. 10×20 cm) of the dyed fabric after curing and impregnate it with a solution of
______________________________________2.5 g/l Marseille soap2 g/l soda ash calc.2 g/l sequestering agent______________________________________
at 80° C. for approx. 10 minutes, stretch out and brush with a hard Perlon hand brush at constant pressure (1 kg). 50 double strokes are normally used.
Then rinse and dry the specimen. Compare the pigment abrasion of the brushed specimen with the fixed original dyeing. If no pigment abrasion is observed, crosslinking is complete.
EXAMPLE 1
The procedure of Comparison 1 was repeated except that 8 g of Polyisocyanate 1 was used instead of the melamine/formaldehyde condensate. Printing and fixing were carried out in the same way as in Comparison 1.
The prints of Comparison 1 and Example 1 were tested by the brush-washing test with the following results:
______________________________________Comparison I Example 1______________________________________Serious damage on Very slight, barely noticeableboth substrates damage on both substrates______________________________________
EXAMPLE 2
Printing from aqueous dispersion
Binder/thickener mixture: 5 g of Emulsifier VA, 4 g of Emulsifier WN, 25 g of acrylic acid/acrylamide copolymer (in the form of a 29% dispersion), 114 g of acrylate binder, and 50 g of carbon black were introduced into 802 g of water. The mixture was processed to colored pastes using three different quantities of each of the crosslinking agents (A)-(D) as listed in the following table:
______________________________________ 1 2 3______________________________________Binder/thickener mixture 995 g 990 g 985 g(as described above)(A) Melamine/formaldehyde 5 g 10 g 15 gcondensate(B) Polyisocyanate 2 5 g 10 g 15 g(C) Polyisocyanate 3, 5 g 10 g 15 g80% in propylene glycoldiacetate(D) Polyisocyanate 4 5 g 10 g 15 g______________________________________
The printing pastes were applied to mercerized cotton cloth and also to bleached cotton cloth. The prints were fixed (i) in air (i.e., simply left to dry), (ii) for 5 minutes at 80° C., and (iii) for 5 minutes at 80° C. and then for another 5 minutes at 150° C. To determine the fastness values, the brush-washing test (50 times) was carried out immediately after fixing, 3 days later and then 1 week later. To evaluate the stability of the printing pastes, printing tests were carried out with the same printing pastes 1 day after preparation of the pastes and 3 days after preparing of the pastes. The testing method is described above.
Where the prints were only "fixed" in air by evaporation of the water, the polyisocyanate used for test (C) was the most favorable insofar as the fastness values of the prints are concerned. However, after storage for 24 hours, the prints could no longer be fixed with these favorable fastness values. However, if new crosslinking agents were added, the original fastness values were again obtained. Test (D) provided equally good results only after 2 days' drying in air. However, drying at 80° C. brought this crosslinking agent to the high fastness level as quickly as (C). The polyisocyanate used for test (A) was not effective as a crosslinking agent up to 80° C. and showed the favorable fastness values only at 150° C.
The quantities of 10 and 15 g of crosslinking agent did not produce a significant increase in the fastness level. A quantity of only 5 g of crosslinking agent was sufficient for the fastness level achieved.
EXAMPLE 3
The printing pastes of Example 2 (A)-(C) were applied to woven and knitted cotton fabrics by rotary printing machine. The prints were fixed in the same way as in Example 2. Prints having good performance properties and good feel were obtained. The fixing conditions became apparent in the same way as in Example 2.
EXAMPLE 4
Example 2 was repeated except that 120 g of polyurethane binder were used instead of the acrylate binder and no pigment was used. 10 g of Polyisocyanate 1 was added as crosslinking agent to 990 g of this binder mixture. A light high-quality cotton was printed with this printing paste and the resultant printed textile was tested in a Fade-O-Meter. Resistance to yellowing and fastness to wet brush-washing were satisfactory.
EXAMPLE 5
The procedure of Example 3 was repeated except that the formaldehyde donor was replaced by 16 g of a 50% solution of triglycidyl urazole in diacetone alcohol.
Fixing after storage for 2 weeks at room temperature and after 5 minutes at 80° C. resulted, after the brush-washing test, in no sign of abrasion of the printing of the textile.
EXAMPLE 6
The procedure of Example 5 was repeated using 16 g of a 50% solution of 4,4'-diglycidyl-2,2-propane in diacetone alcohol. An improvement in brush-washing was again achieved by fixing at 80° C.
EXAMPLES 7 AND 8
Colored pastes were produced as in Example 1 using the binder/thickener mixture of Example 1.
______________________________________Example No. 1 2 3______________________________________Binder/thickener mixture 995 g 990 g 985 g(as described in Example 1)7) Polycarbodiimide according to 5 g 10 g 15 gExample 1 of U.S. Pat.No.4,977,219 with 9.8% carbo-diimide groups in methoxy-propyl acetate8) Triglycidyl isocyanurate in 5 g 10 g 15 gthe fom of a 30% dispersionin diacetone alcohol______________________________________
The printing pastes were applied as in Example 1 to mercerized cotton and to bleached cotton fabrics. The prints were fixed for 5 minutes at 80° C. and also for 5 minutes at 80° C. and then for another 5 minutes at 150° C. To determine the fastness values, brush-washing 50 times) was carried out immediately after fixing and also one week later.
Test Examples 7 and 8 give good results only at 80° C.; at 150° C., Examples 7 and 8 give slightly poorer fastness values than Example 1. In Example 8, the 10 g and 15 g quantities of crosslinking agent provided better results than 5 g. | The present invention relates to textile printing pastes containing modified polyisocyanates, modified polycarbodiimides, or trifunctional polyepoxides as crosslinking agents for the binders present therein. | 3 |
This is a continuation of application Ser. No. 560,068, filed Dec. 9, 1983 now abandoned.
BACKGROUND OF THE INVENTION
This invention relates to a method and apparatus for remote metering particularly suited for metering electrical energy.
Because of the drastic increase in energy costs in the past ten years, it has become increasingly more desirable to make efficient use of available energy and the plant that is used to produce it. Individual accountability for energy consumption has proven to be a powerful incentive to energy conservation, leading to increasing demands for individual metering of the energy consumption of each individual entity where some form of master metering might previously have been used. Thus, instead of accepting a percentage share of the electric bill derived from a master meter in an office building or condominium, tenants are increasingly demanding individual metering of their own electrical energy usage. Individual metering rewards those tenants who practice conservation by allocating to them only their actual energy costs. It is advantageous to the landlord because it transfers to the tenant resonsibility for costs that tend to rise faster than the rent and over which the landlord has no control. Perhaps most important, to the electric utility and the community, individual metering means more efficient use of existing generating capacity and therefore at least some respite in the struggle over where to locate and how to finance additional capacity.
While there are substantial incentives for individual metering, the conventional electromechanical meters are not an adequate solution. These devices must be read manually, requiring a large labor force and imposing a difficult problem in where to locate them. As will be appreciated, the location problem is particularly acute when individual meters are to be retrofitted in a building that was formerly master metered. Electromechanical meters also have several inherent problems. They are not very accurate, typically being designed for accuracies of +0.5% under ideal conditions and +2% of a specified range; they slow down with age and at low currents produce low readings; they are position and magnetic field sensitive; and their accuracy in monitoring electrical energy consumption by some modern appliances or under transient conditions may be very poor.
Another shortcoming of conventional electromechanical meters is their inability to provide at reasonable expense time-of-day metering so that power companies could charge for power as a function of load factors. Such capability has become increasingly more desirable as a means of distributing load and therefore diminishing the need for more generating capacity.
Numerous techniques have been devised for remote metering. See, for example, U.S. Pat. Nos. 3,153,780, 3,747,068, 3,818,481, 4,004,097, 4,139,735, 4,161,720 and 4,239,940. While numerous techniques have been devised, there are many problems with them. Some techniques require the use of separate communication lines for the meters, while those which use current carrier systems are subject to severe noise problems. Few, if any, take full advantage of the size reductions, accuracy and economy available from digital computer circuitry.
SUMMARY OF THE INVENTION
We have devised a method and apparatus for remote metering that relies on carrier current signalling and makes full use of digital signal processing to improve the accuracy of the metering. In accordance with our invention, the apparatus has three levels of intelligence comprising a central billing computer, one or more communications interface processors (CIP) connected through the phone system to the central billing computer, and one or more remote sensing modules (RSM) located at each site where measurements are to be made. Communications between the RSMs and CIP are by transmission over the AC power lines to which they are connected. Information flows bi-directionally through these three levels of intelligence.
The Central Billing Computer is remotely located from the metering site(s) and is the ultimate point within the system for data processing and back-up storage. It is the point from which individual customer billing is generated. Illustratively, the billing computer consists of a microprocessor with RAM, support circuitry, a floppy disk drive for mass storage, and a modem for telephone-line communications to the multiple CIPs. The interface from microcomputer to modem is standard RS-232, and Frequency Shift Keying (FSK) is used for data communications. At present, a Signalman modem, with a baud rate of 300, is implemented.
The individual CIPs are likewise interfaced to their telephone-line modems by standard RS-232. The CIP consists of a microprocessor with RAM and support circuitry. Its memory is battery-powered to protect against data loss. Through its power line interface, the CIP communicates with, and supervises the functions of, from one to 4096 individual RSMs. For such communications, the CIP uses a 60 baud FSK modem which transmits and receives the signals required for communication over local AC power lines. Six possible channels are available for data communication, each of which carries the same data.
The RSM is a metering device placed within the dwelling or business of the individual customer. Like the CIP and the billing computer, the RSM is a stand-alone microcomputer system. It is capable of full operation and data retention even in the event its CIP supervisor should fail. The RSM is capable of gathering various kinds of data regarding electrical energy, gas usage, and other information input through contact closures or electrical pulses, and of storing this information within its own non-volatile memory.
In normal operation, the RSM is constantly scanned by its CIP supervisor approximately once every 2N seconds where N is the number of RSM's under control of a particular CIP supervisor and two seconds is the approximate time to scan one RSM. The CIP condenses and analyzes data received from its RSM network and stores it in battery-powered CMOS RAM. This data includes bit-error rate, energy demand, and time-of-day information. In the event of RSM failure, the data the CIP has previously gathered is available, in condensed form, to the central billing computer. RSM failure or malfunction is recognized by the CIP within one scanning interval. Worst-case data loss, therefore, is determined by the speed of RSM replacement.
The CIP's data store is accessed once daily by the central billing computer, which then replicates the metering information into its own back-up archives. In the event of a CIP and an RSM failing in tandem, the Central Computer can be no more than one day behind in its collection of system data, but the techniques of multiple redundant storage outlined above significantly limit data loss and the corresponding loss of revenue involved in metering operations.
The RSM comprises sensors for reading parameters such as current and voltage which are used in measuring energy transmission, sampling means for sampling these parameters and digitizing them, means for calculating energy transmission from the sampled values, an accumulator for accumulating the calculated value and a communication system for transmitting the accumulated values to the CIP.
The RSM is an individual microcomputer-driven, electronic meter having the capability of standard KWH reading as well as time of day metering.
The meter is a "stand-alone," independent unit with full data processing and data retention capability. In the event of power failure, data presently being accumulated is stored in a non-volatile memory, thus preserving data integrity and guarding against data and revenue loss. The meter has full capability for data communications to the CIP by means of frequency-shift keying (FSK)/power-line carrier (PLC) techniques. Data communications are further enhanced by multi-channel communication techniques, whereby the meter receives the same signals over six distinct channels, uses a valid data check to test the received signals to locate an interference free channel and transmits data back to the CIP over the first such channel it locates. This provision guards against errors caused by both random interference common to AC power lines as well as any intentional interference.
The metering itself is accomplished through a special sampled system, where hardware and software error correction features interact to produce high-precision readings (less than 1% errors). Preferably, this sampling system involves separate voltage and current signals being sampled at a given rate and then multiplied and summed to yield power and energy readings. Any system offset present is minimized by dynamic offset-cancelling.
The design of the meter also provides safeguards against a number of problems inherent in such technology.
1. Random transient malfunction, resulting in program "derailment" is a characteristic of microprocessors. To protect against this contingency, special circuitry is resident in the meter which monitors the stability of the meter's central processing unit and resets it should instability be detected. In this way, meter processing continues uninterrupted, and no manual reset of the unit is required.
2. The meter also has the capability of detecting power failure in its incipient stage and storing its data in non-volatile memory before full power loss is experienced. When power is restored, recall of the stored data is automatic and the meter resumes operation immediately.
3. Access to data being stored in RAM is guarded by special gating circuitry which prevents data loss due to transient malfunction.
4. Current inputs tapped from building power lines are stepped-down and isolated by special transformers. The nominal error of the transformer type is compensated for through the meter firmware. If required, the actual characteristics of the individual transformer used may be compensated for through software.
A BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects, features and advantages of our invention will be more readily apparent from the following detailed description of a preferred embodiment of the invention in which:
FIG. 1 is a block diagram of the remote metering system of our invention;
FIG. 2 is a block diagram of an illustrative embodiment of a remote sensing module (RSM) of our invention;
FIG. 3 is a block diagram of a meter circuit of the RSM of FIG. 2;
FIG. 4 is a block diagram of an illustrative embodiment of a data communication circuit of the RSM of FIG. 2;
FIG. 5 is a block diagram of a memory protection section of the RSM of FIG. 2;
FIGS. 6 and 7 are schematic diagrams of portions of an AC line interface for the RSM unit;
FIG. 8 is a schematic diagram of a power supply for the RSM unit;
FIG. 9 is a schematic diagram of a clock generator of the RSM unit;
FIG. 10 is a schematic diagram of voltage and current sampling circuits of the RSM unit;
FIG. 11 is a schematic diagram of an analog-to-digital converter and reference voltage generator portions of the RSM unit;
FIGS. 12, 13 and 14 are schematic diagrams of portions of the communications section of the RSM unit;
FIG. 15 is a schematic diagram of an illustrative embodiment of a data protection circuit of the RSM unit;
FIGS. 16A, B are schematic diagrams of a central processing unit of the RSM unit;
FIGS. 17A, B are schematic diagrams of an illustrative embodiment of two programmable Input/Output interfaces for the RSM unit;
FIG. 18 is a schematic diagram of a meter display section for the RSM unit.
FIG. 19 is a block diagram of the Communications Interface Processor (CIP).
FIG. 20 is a block diagram of the Central Processing Unit of the Communications Interface Processor (CIP-CPU).
FIG. 21 is a block diagram of the Power Line Carrier unit of the Communications Interface Processor.
FIG. 22 is a schematic diagram of the Master CPU and Clock of the Communications Interface Processor.
FIG. 23 is a schematic diagram of the Decoding Circuitry of the Communications Interface Processor.
FIG. 24 is a schematic diagram of the Buffer Address Lines to LOC of the Communications Interface Processor.
FIGS. 25A, B are schematic diagrams of the Parallel Input/Output (I/O) of the Communications Interface Processor.
FIG. 26 is a schematic diagram of the Insane and Power Fail circuits of the Communications Interface Processor.
FIGS. 27, 28 are schematic diagrams of the buffer circuitry of the Communications Interface Processor.
FIG. 29 is a schematic diagram of the Clock Back Up Circuit of the Communications Interface Processor.
FIGS. 30A, B are schematic diagrams of the Serial Interface Ports and RS232 Buffers of the Communications Interface Processor.
FIGS. 31A, B are schematic diagrams of the Input/Output (I/O), Random Access Memory (RAM) and Read Only Memory (ROM) and Data Bus circuitry of the Communications Interface Processor.
FIG. 32 is a schematic diagram of the Master Address Bus of the Communications Interface Processor.
FIG. 33 is a schematic diagram of the Master Status circuitry of the Communications Interface Processor.
FIG. 34 is a schematic diagram of the Disk Controller circuits of the Communications Interface Processor.
FIG. 35 is a schematic diagram of the Master Control and Utility circuitry of the Communications Interface Processor.
DESCRIPTION OF PREFERRED EMBODIMENT
As shown in the system block digram of FIG. 1, a preferred embodiment of our invention comprises a central billing computer 20, a plurality of communication interface processors (CIP) 25, and a plurality of remote sensing modules (RSM) 30 connected to each CIP.
In the preferred embodiment of the invention, the system is used to measure electric power consumption on a customer's premises. Accordingly, each RSM is typically located on the customer's premises and the CIP to which it is connected is relatively close by, for example, in the same building.
The central billing computer is connected to each of the CIP's by a conventional data communication system using ordinary telephone lines 22 and readily available modems (not shown). The individual CIP's are connected to the RSM's they service by a carrier current communications system using the electrical power line 27 between the CIP and its RSMs.
A block diagram illustrating the major components of an RSM is set forth in FIG. 2. As shown therein, the RSM comprises a central processing unit (CPU) 32, a random access memory (RAM) 34, a read only memory (ROM) 36, and a memory protection circuit 38. The RSM further comprises a power line interface and step-down transformer 42, a power supply 44 and a clock generator 46. For communication with the CIP, the RSM further comprises a data transmission power line interface 52, a data transmission transmitter and receiver 54, and an inuut/output (I/O) interface circuit 56. For performance of its metering function, the RSM unit comprises a voltage and current interface 62, metering circuitry 64, and an I/O interface 66. A LED display 68 is also connected to the CPU through I/O interface 66.
The CPU illustratively is an Intel 8085 CMOS microprocessor, RAM 34 is a XD2210 non-volatile random access memory manufactured by Xicor Corp. of Milpitas, Calif., and ROM 36 is an MM2732 read only memory. I/O interfaces 56, 66 illustratively are an 81C55 and an 82C55 respectively.
Throughout the specification, integrated circuits and devices of the LM-, CD- and LF-type are generally available from National Semiconductor. Similarly, LS-type devices are generally available from Fairchild.
A more detailed block diagram of the metering circuitry is shown in FIG. 3. As indicated therein, inputs to the metering circuit include three inputs, V1, V2, V3 which are representative of the voltage on each of the three lines of a three phase power line, and three inputs I1, I2, I3 which are representative of the current on the corresponding three power lines. These inputs and ground are applied to an analog multiplexer 72 along with control signals phase 1, phase 2 from the CPU. The inputs representative of voltage are applied by the analog multiplexer to a voltage sample/hold circuit 74 where they are sampled and the sampled values are applied to a voltage/current multiplexer 76. The inputs representative of current are applied by the analog multiplexer to a variable gain amplifier 82, the output of which is applied to a current sample/hold circuit 84. Sampled values of the current are also applied to the voltage current multiplexer.
In general, it is preferred that sampling be carried out at a frequency which does not exceed twice the highest harmonic frequency present in the parameter being sampled which the meter is capable of sensing. In sampling AC voltage and current, the sampling frequency preferably has the following characteristics: (1) the sampling frequency is not equal to the frequency of the alternating current, (2) the harmonics of the sampling frequency are not equal to any harmonic below the fifth harmonic of the frequency of the alternating current, and (3) the sampling frequency is no more than three and one-half times the frequency of the alternating current.
The output of the voltage/current multiplexer is applied through a level shifter 78 to an analog to digital converter (ADC) 90; and the output of the ADC is made available to the CPU on a bidirectional data bus 40. The range of the variable gain amplifier can be selected by a coded signal from the CPU on three input lines range 1, range 2, range 3, and the amplifier can be zeroed under control of the microprocessor by application of the signal AZ to an auto-zero circuit 86. Operation of the voltage and current sample and hold circuits 74, 84 is controlled by the CPU by the signals VSH and ISH, respectively. Operation of the voltage/current multiplexer is controlled by the CPU by the signal VIMUX. A reference generator 88 supplies a voltage reference signal VREF to the ADC and the CPU controls the analog to digital conversion process by the signals CS1, RD and WR. The ADC indicates that it is ready to begin a conversion by providing the signal ADC RDY to the CPU. Further details concerning the metering section are set forth in FIGS. 10 and 11 below.
A more detailed block diagram of the data receiver/transmitter 54 is set forth in FIG. 4. As shown therein, a received signal from AC line interface 52 is applied through switch 102 and isolating transformer 104 to a 30-50 kHz filter 106. The output of the filter is applied to a receiver mixer 108 which mixes the received signal with the output of a switched frequency source comprising a 2 MHz clock 110 and a programmable divider 112. The output of the mixer is applied to a band pass filter 114, a limiter 116 and a phase locked loop demodulator 118A. The demodulated signal is then applied through a receive switch 120 to a filter comparator 122 and a receiver latch 126. The output of the latch is the received data RDAT which is made available through I/O interface 56 to the CPU (FIG. 2).
Data to be transmitted, XDAT, is provided to a transmit latch 130 and is converted to an analog signal by a transmitter digital to analog converter (DAC) 132. The analog signals from the DAC are applied through the receive switch 120 to a voltage controlled oscillator 118B which converts the analog signals to signals of differing frequencies depending on the data to be transmitted. Such a variable frequency signal is applied through a transmitter control 134 to a transmitter mixer 136 where it is mixed with radio frequency signal from the local oscillator. The output of the mixer is applied through a level translator 138 and a low pass filter 140 to a power amplifier 142. The amplifier output is applied through a switch 144 and isolating transformer 104 to the AC line interface 52 for transmission over the power line to the CIP. Further details concerning the RSM transmitter and receiver are set forth in FIGS. 12, 13 and 14 below.
A more extensive block diagram of memory protection circuit 38 is set forth in FIG. 5. As shown therein, the circuit comprises an "insane" circuit 92 for protecting against CPU failure, and a power failure detector 94 for identifying incipient power failure. A security gating circuit 96 prevents inadvertent operation of reset circuitry and a protective flip-flop 98 determines when meter data is to be stored in non-volatile memory in the event of power failure. One-shot 100 provides for recall of data upon recovering from power failure.
A.C. Line Interface (FIGS. 2, 6 and 7)
FIGS. 6 and 7 are schematic drawings of the AC line interface. As indicated in FIG. 6, a terminal block 200 is provided for connecting the RSM circuitry to the AC power lines 210, 220, 230 and the neutral line 240. As shown, each of the power lines is connected directly to one of the inputs phi 1, phi 2, phi 3 on terminal block 200 and the neutral line is connected to input N. These connections are used to generate signals representative of the voltage in each of the power lines, to derive a power supply and 60 Hz clock signal, and to provide for carrier current signalling. In addition, current information is derived from each of the power lines by a current transformer 212, 222, 232 coupled to each power line and connected to one of the pairs of inputs N1, I1; N2, I2; N3, I3; respectively, of terminal block 200. Protection against transients and high current levels is provided by the pairs of oppositely-poled diodes D1-D12. Protection against excessive current levels on the voltage lines is provided by fuses F1-F5. The voltage signals are connected through connector TB-1 of FIGS. 6 and 7 to the circuitry of FIG. 7. In similar fashion, the signals representative of current are connected through connector TB-2 of FIGS. 6 and 7 to the circuitry of FIG. 7.
As shown in FIG. 7, signals representative of the voltage on each of the power lines are applied to voltage dividing networks R4-R18 where they are divided down to produce signals V1, V2, V3 which are voltage signals having a range of approximately 1.3-2.0 Vrms proportional to the voltage in power lines 210, 220, 230. Signals for the power supply and clock generator are applied to a center tapped transformer T1, the output of which is made available on leads S1, S2, CT. Data signals are applied to an AC line interface comprising a luf capacitor C509, Transorb 7.5 volt transient suppressor D404, and resistor R506. The interface output is provided on leads CCL, CCN. The capacitor blocks the 60 Hz signal of the power line but allows the frequencies of interest (30-50 kHz) to pass. The resistor protects the transient suppressor in the event of inadvertent opening of the input lines.
The signals representative of current levels in power lines 210, 220, 230 are converted to proportional voltage levels by three resistive networks R44-R52 which shunt the current transformers. The outputs of these circuits are leads I1, I2, I3.
Power Supply (FIG. 8)
The RSM power supply (FIG. 8) is a single, center-tapped, full-wave bridge rectifier D405-408 providing inputs to three linear voltage regulators U401-403. Regulators U401 and U402 provide positive outputs of 8 and 5 volts respectively. Both U401 and U402 tap their inputs from the same positive, unregulated line. To guard against regulator drop-out, an LM-2930-8 integrated circuit is used for the 8 volt line. This component is characterized by a maximum drop-out voltage of 0.6 VDC. The 5 Volt output is provided by an LM7805 Standard regulator.
Regulator U403 provides the supply's single negative voltage. Three IN4148 signal diodes D401-403 are placed in series with a ground terminal of an LM7905 regulator in order to boost the regulated output to -7 VDC. Output capacitors C429, C663, and C664 are added to improve transient response and noise rejection.
In addition to the standard filtering functions required on the regulator input side, a 10,000 uF capacitor, C660, is connected across the positive inputs to provide a system hold-up time of at least 10 ms in the event of power failure. This aspect of the RSM circuitry is included to ensure data integrity. Further information on data protection features is set forth in conjunction with FIG. 15 below.
Raw Clock Generator (FIG. 9)
Several on-board components of the RSM unit require a 60 Hz clock for proper device operation. As shown in FIG. 9, this clock is derived by a clock generator from the 115 Vac 60 Hz signal present on the local power lines feeding the RSM power supply.
The inputs of the clock generator are taken from the secondary terminals of power transformer T1 (FIG. 7) in parallel with the inputs to the bridge rectifier described in FIG. 8. The signals present are approximately 30 volt peak-to-peak, 60 Hz sine waves, which are input to an LM339 differential comparator U40A through two identical voltage divider circuits. The four divider circuit components R200-R203 are 11K ohm, 1% tolerance precision resistors. An oppositely-poled dual-diode clamping circuit D28, D29 is connected across the comparator to insure that the differential inputs remain within a specified range.
Although the comparator output is a 60 Hz wave, signal jitter and impulse noise present make it unacceptable for clock applications. Accordingly, the signal is low-pass filtered through an RC circuit formed by R205 and C202. This filter integrates the square wave, producing a triangular wave output with some degree of phase shift. The filter output is presented to an LM339 comparator U40B, configured as a Schmitt trigger, which converts the triangular input to a 60 Hz square wave output without spurious edges. This output is the "raw" clock used in the timing of circuitry described in connection with FIGS. 14 and 15 below. The output of the clock generator, described hereinabove, is used to clock switch U42, which obtains its pins 5 and 3 inputs from the I/O part of 81C55 (U17) in FIG. 17B. One of these two inputs is a one and the other is a zero. As U42 is clocked its output switches between the two inputs, generating a 60 Hz clock output. If the two input levels are swapped by the microprocessor, the generated 60 Hz clock is inverted.
Advantageously, the clock generator uses precision resistors and capacitors to implement a clearly defined time-delay between the transformers' secondary input signals and the Schmitt trigger clock output.
Meter Section (FIGS. 3, 10 and 11)
The RSM meter section is a microcomputer-controlled system in which simultaneously-sampled voltage and current values of a given phase are presented sequentially to an analog-to-digital converter (ADC). The ADC, in turn, provides digital values to the RSM CPU, which performs the calculations necessary to derive meaningful energy-usage data.
As indicated in the discussion of FIG. 6, six inputs, three of current and three of voltage corresponding to the three phases of the local power system, are tapped from the power lines serving the individual energy user. The six metering inputs are referenced to the circuit ground which is tied in common with power line neutral. Advantageously, care should be taken to avoid ground loops and to protect from noise from the power lines.
The three-phase inputs are switched into the metering circuitry by a CD4052 analog multiplexer U1 (FIG. 10). Current and voltage inputs of a given phase are switched through simultaneously to be sampled and processed together by the RSM circuitry.
The voltage signal, which has a relatively narrow and clearly defined range between 1.3 and 2.0 Vrms, is routed directly to an LF 398 sample-and-hold circuit U6. The voltage samples are held on a 0.022 uF polypropylene capacitor C2 having the low dielectric loss necessary for accurate sampling.
The voltage sample is then switched through a voltage-current multiplexer V-I MUX 76 (FIG. 3) into an analog-to-digital converter ADC 0803 U9 manufactured by Intersil (FIG. 11).
The three current inputs which are expressed in terms of voltage have a wide dynamic range of approximately 200-to-1. For this reason, a two-stage variable-gain amplifier with computer-controlled auto-zero and auto-ranging support circuitry is inserted between the input multiplexer U1 and an LF398 current sample-and-hold circuit U5. The current samples are held on capacitor C1 which is identical to C2.
Two amplifier stages U2A, U2B are required because the gain-band width product available at either single stage is not sufficient to provide the desired gain along with the low distortion and phase-error necessary for proper meter operation.
Because the two amplifier - gain stage has large gain, offsets at its input would become large at its output. To minimize this potential problem an auto-zero integrator U11 is inserted around U2B. The auto-zero circuit has two positions, zero and hold. When U7A connects the output of U2B to R32, the integrator zeros the output of U2B, compensating for any offset at its input. When U7A connects R32 to ground U11 holds its output and allows any additional signal input to pass through. In order to assure that only offsets are present at the input of U2B, when the zero position is selected an additional position is provided on U1 p11 to ground the overall input of U2A. After zeroing the output of U2B with U4 selected for maximum gain and U1 selected to ground the input, all other positions of U4 will also have been zeroed. This design advantageously allows for one integrator capacitor to correct all possible gain positions of switch U4.
Resistors R31, R34 and R35 are inserted for circuit protection of switches U7A, U7B at input pins 3, 12 and 13. Sample-and-hold circuits U2 and U5 operate with an 8 volt positive supply and would otherwise be capable of supplying damaging inputs into the 5 volt supplied switches U7A, U7B.
The current and voltage sample outputs from V-I MUX vary within a range of +2.5 volts. The ADC require inputs within a 0-5 volt range. As shown in FIG. 11, the voltage level from the V-I MUX is buffered and level shifted by U8. Resistor R40 and diodes D18 and D17 protect the input of the ADC from overload.
The ADC, U8B and U40D (FIG. 15) require an input reference voltage which is supplied by the reference generator circuit. This circuit operates from the unregulated voltage tapped from the positive side of the bridge rectifier. Generation of the reference voltage requires a relatively constant current supply. In addition, the power-fail detection circuit discussed in conjunction with FIG. 15 below requires that the reference voltage remain constant while the power supply voltages rise and fall. For these reasons, resistor R42, 5.6V Zener diode D16 and resistor R43 supply current to the LM336Z-2.5 reference diode. The reference diode is configured in the temperature compensating mode and is adjusted for 2.40 volts for minimum temperature coefficient. The voltage is then buffered by an LF411 op-amp. The buffer is required to drive the circuits connected to the voltage reference line (VREF).
Upon receiving a write command from the processor, the ADC begins the conversion process. When digital information is ready for the CPU, the ADC informs the processor with an ADC ready signal and the information is read out over the system data bus. As indicated above, each output value from the ADC is then corrected for circuit offsets by use of the correction factors stored in the memory of the microprocessor.
Communications Section (FIGS. 4, 12, 13 and 14)
The communications section is that portion of the RSM unit dedicated to data communications between the RSM processor and its CIP supervisor. Information between the two modules is transmitted over six, 100 Hz bandwidth, 60 baud, FSK channels, spaced apart in the band between 30 and 50 kHz. The system is half-duplex send/receive, i.e. either the CIP or the RSM is transmitting at any given time. The same data is replicated on all six channels and transmitted simultaneously from the CIP to the RSM. The RSM receives on a single channel and transmits back to the CIP on the particular channel it received on.
The location of the bit centers in the 60 baud data stream is defined by the 60 Hz clock generator; and synchronization between the transmitter/receiver of the CIP and that of the RSM is maintained by deriving the clock signal for both the CIP and RSM transmitter/receivers from the same 60 Hz power line. Despite group delays in the receiver filters and phase delays in the raw clock generators, there is a clearly defined time delay between the CIP and the RSM which is compensated for by the computer program in the CIP.
Component-by-component discussion of the communications section is presented first from the standpoint of data reception from the CIP, through the receiver circuitry to the RSM processor, followed by discussion of the transmit mode.
Data enters the RSM through the CCL and CCN terminals shown in FIG. 7. An AC line interface comprises a luf capacitor C509, a Transorb 7.5 Volt transient suppressor D404, and a resistor R506. The capacitor blocks the 60 Hz signal of the power line but allows the frequencies of interest (30-50 KHz) to pass. The resistor protects the transient suppressor in the event of a circuit failure which opens circuitry subsequent to the transorb.
The received signal is processed by the circuitry of FIGS. 12-14 configured as a classic superheterodyne PLL receiver.
In the receive mode, a central processor-driven relay switch KIA is open. This places a 39 ohm resistor R505 in the signal path. This resistance, added to the average impedance of the line, provides a 50 ohm input impedance required by the initial filter stage of the receiver.
As discussed above in conjunction with the meter section, circuit ground is referenced to the neutral of the local power lines. Because the carrier current line may not have the same neutral as the power lines connected to the meter inputs, the incoming data signals are transformer-isolated via transformer L1. The signals are then presented to a 3-pole, LC, bandpass filter is input to transformer L3 having configured in a pi-type section. The filter has an output impedance of 50 ohms, and a center-tapped output providing differential signals for the following stage.
The filter output RRF is applied to a receiver mixer of FIG. 13. The mixer is a CD4053 analog switch which takes the differential output of the preceding filter, selects either side of it, and multiplies by ±1 to provide the intermediate frequency. The mixer obtains its local oscillator input from a central processor-controlled, counter/frequency-divider block (FIG. 13).
The counter comprises a 74LS169 programmable 4-bit counter U31 that divides the 2 MHz clock output of the CPU by integral values ranging from 11 to 16. Each of these values is then further divided by a factor of four by two serially-connected CD4013 D-flip-flops U32A, U32B. This yields six values of frequency in the range between 30 and 50 kHz corresponding to the six FSK communications channels.
The signal input to the mixer is six channels each of which contains an RF signal carrier and shifting values of 225 and 275 Hz which are FSK signals representing the mark and space (Binary 0 and 1) elements of the data being communicated. The data being communicated in each channel is the same. The RSM microprocessor uses a parity check to determine if the data recieved on a first channel is good. As long as the data is good the microprocessor continues to monitor the data received on that channel and uses the same channel to transmit data to the CIP. If, however, the received data fails the parity check, the microprocessor tests the other data channels, in turn, until it finds a good channel and then uses that channel for data communication. The microprocessor switches from one channel to another by modifying the number it presents to the counter U31 that is used to divide the 2 MHz clock signal.
This approach of multi-channel communication, with six widely separated channels available where only one is necessary for communication, and a very narrow bandwidth for communication on each channel, allows for a high degree of protection against deliberate and non-deliberate signal interference.
The mixer output is connected to a 250 Hz filter/limiter 167 in a double side-band receiver configuration. (Because the CIP transmits single side band, one side band is received as a noise channel.) The filter (FIG. 14) is a four-pole Butterworth active filter using an LF347 operational amplifier U34 with four multiple feedback, single-pole bandpass filters. The filter has a gain of approximately 10. The limiter provides further amplification and clips the signal. The limiter output is fed through a 1000K ohm protection resistor R357 to the input of U36, CD4046 single-pole filter-demodulator. The voltage controlled oscillator (VCO) frequency is 200 Hz for input at the negative rail and 300 Hz for the positive. This places the mark and space frequencies of 225 and 275 Hz at 1/4 and 3/4 of the rail to rail values respectively. The VCO control line of the PLL passes through central processor controlled receive/transmit switch U42A and enters a two-pole data filter/comparator 168, depicted in more detail in FIG. 14 and comprising U35C, D.
The filter section, with a rolloff at 70 Hz, eliminates the 250 Hz IF signal and its harmonics. The comparator squares up the signal and yields the 60 Baud data. The now fully demodulated signal enters a receiver latch U37A (pins 1-6), which is clocked by the 60 Hz line-derived clock discussed in conjunction with FIG. 9. When freed from its immediate tasks, the central processor reads in the data from the latch.
Data to be transmitted is provided by the CPU to a transmitter latch U37B (pins 7-12), along with the 60 Hz clock from FIG. 9. The latch output is presented to a transmitter digital-to-analog converter (DAC) U42B. The DAC is a two-position analog switch, with an external voltage divider circuit which selects either 1/4 or 3/4 of the ±5 to -7 rail-to-rail voltage swing. These voltages are presented to the VCO of the CD4046 PLL demodulator U36 through U42A. The VCO is adjusted during manufacture to produce either of the two frequencies, 225 Hz Mark, 275 Hz Space, depending on the position of the DAC switch. The VCO output signal is connected through a 100K ohm protection resistor R510 to a pin 5 input to U38 of a CD4001 mute transmit circuitry. In the PLC receive mode, the RX control signal disables data transmission to the CIP. In the transmit mode, the 4001 NOR gate passes the transmitter output from the VCO and local oscillator frequencies from the counter into inputs to a CD4053 transmitter mixer U33C.
The local oscillator frequencies are the same six values available to the receiver. The particular frequency selected by the microprocessor is mixed with the mark and space values to produce a frequency shift keyed (FSK) signal in which the frequency of the signal depends on whether a mark or a space is present at pin 10 of the transmitter mixer.
The mixed digital signal is then presented as the select input of a transmitter level translator U33B. The switch inputs of the translator are configured such that the XRF output is proportional to the positive unregulated voltage tapped from the RSM power supply. This is to provide the maximum possible amplitude for the data output and avoid clipping during low-voltage operation. The translator presents a 470 ohm output impedance to the following stage which is a 60 KHz low pass filter (FIG. 12). An input capacitor C513 blocks the DC offset from the previous stage. The filter eliminates any objectionable harmonics generated in the mixing process and presents its output to a linear power amplifier U41. The amplifier provides the voltage and current gain required to transmit directly onto the AC line.
It is necessary that the amplifier output be switched in by relay switch K1B. Without provision of the relay, the output impedance of the amplifier will load down the line and attenuate the received signal to unacceptable levels. It should be noted that the transmit signal is turned off before switching of the relay; and the relay is closed prior to enabling transmit. This allows switching under no-load conditions and increases relay life by a factor of about 100.
Protection Section (FIGS. 5 and 15)
Data integrity takes on special significance in the RSM system. Because the data gathered and processed by the RSM computer is directly related to revenue, loss of data is, in many cases, equatable with loss of revenue. For this reason, there are a number of design features built into the RSM for the purpose of decreasing the likelihood of data loss. Transient malfunction, for whatever reason, can cause the RSM CPU to "jump its program" and require a manual reset to restart it. For the period of downtime involved, data will be lost and irrecoverable to the unit. For this reason, the RSM hardware, in effect, monitors CPU stability and resets the processor if malfunction is detected. This portion of the RSM circuitry is called the "insane circuit". The initial input to the insane circuit is the 60 Hz clock discussed above in conjunction with FIG. 9. The 60 Hz clock is routed from the output of the raw clock generator to a CLK2 input at pin 3 of D-type flip-flop U39A. U39A is a CD4013 dual D flip-flop with its pin 5 input tied permanently to +5 volts. On the rising edge of the 60 Hz clock, the Q output of flip-flop U39A goes high and Q goes low. The Q high "flag" output alerts the processor, through its 8IC55 port, that a reset of the CPU will take place in 8.33 ms (1/2 the cycle of the 60 Hz clock), unless the processor disables this process by pulsing the pin 4 input of the flip-flop through the 8IC55 "RST FL" signal. The internal loop of the CPU is completed within approximately 4.8 ms and, therefore, if the processor is functioning properly, it has sufficient time to respond to the flag test. If the CPU is not responding properly, the Q output from flip-flop U39A will remain low for more than 8.33 ms at which time the 60 Hz clock will also go low, causing both inputs at pins 12 and 13 of a NOR-gate U38A to be low. These inputs, in turn, provide a high input to pin 9 of U38B which is sufficient to send its pin 10 output low and reset the CPU.
The AC coupling to pin 4 prevents clearing of the flip-flop due to DC levels. Were this precaution not taken, the CPU could conceivably "jump its program" and at the same time assert RSTFL, defeating the purpose of the insane circuit. It is much less likely that the processor could "jump its program" and still continue to pulse RSTFL. The CPU RST out signal clears the insane flip-flop upon reinitialization.
A second feature of RSM data protection is provided by a "protect" flip-flop U39B, which directly affects the data integrity of a non-volatile memory U19 (FIG. 16B). The XD 2210 non-volatile memory U19 comprises a conventional static RAM overlaid bit-for-bit with a non-volatile E2 PROM. At any time, data can be transferred between these two sections of memory by the use of the Store and Recall signals. An inadvertent Store is protected against by making such an operation dependent on two separate 8IC55-generated control signals, NOVST and NOVCL. NOVST provides a low input to the D input of protect flip-flop U39B, and NOVCL provides the clock whose rising edge triggers the NOVRAM store function. The store is generated by providing a digital low on the store line output from the Q terminal of flip-flop U39B. By routing the RST FL line to the set input at pin 8 of U39B, store functions are prevented during CPU reinitialization. Further protection is provided for U19 by NOVRAM access control gating (FIG. 16) comprising three 74LS00 NAND gates U23A,B,C. The legitimacy of NOVRAM chip select is insured by gating the read, write and chip select signals generated by the CPU and a NOVTOG signal from the 8IC55 of FIG. 17B.
As its name implies, the Power-Fail detector circuit (FIG. 15) recognizes when the RSM unit is losing power and alerts the CPU to implement the NOVRAM store function. This is accomplished by comparator U40C configured as a Schmitt trigger. As the inverting input at pin 4 of amplifier U40 falls below the reference value applied to pin 5, the pin 2 output snaps high. This interrupts the CPU through the PWRF line. During the time the NOVRAM store operation is being performed, the reset disable signal RDIS is low, clamping pin 8 of NOR gate U38B to an approximately ground level potential and preventing CPU reset. When the store operation is completed, RDIS goes high and the processor is held in reset until power on.
Because the CPU cannot distinguish between a restart caused by an insane circuit reset and a power on reset, the NOVRAM recall function must be implemented by hardware. An insane circuit reset does not produce a RAM store operation beforehand; in other words, after insane reset the CPU will continue its operations where it left off without data loss. During a power-fail cycle, however, a necessary store operation has been performed and recall is necessary upon repowering the system. Recall is accomplished by comparator U40D configured as a one-shot. When pin 2 output of amplifier U40C goes high, the one-shot is initialized; and when the unregulated supply voltage rises past the reference voltage on power-up, the one-shot is triggered, thereby pulsing the recall signal from the pin 1 output of amplifier U40D.
Except for the tamper switch input, external inputs are filtered and protected by resistors R117 to R124, diodes D20 to D27 and capacitors C100 to C103 (FIG. 17B).
Display Section (FIG. 18)
The RSM display section (FIG. 18) comprises an 8-digit, 7-segment China Semiconductor CS-247C display U25, U26, a CD4511 7-segment latch, and driver U14, a 74LS138 decoder U13 and eight transistor buffers Q7-Q14. Multiplexing operations for the display are performed by software. Segment selection is input to the 4511 from the 82C55 output port of FIG. 17A. A 4-bit binary coded decimal number is converted by U14 to a 7-segment positive-logic output code. For example, to display the number 6, the C, D, E, F and G outputs of latch U14 are high. There are no tails on the six and nine digits, and the one digit is right-justified. There are 100 Ohm current-limiting resistors between the output of U14 and the display inputs.
Digit selection is input to decoder U13 from the 82C55 with a 3-bit select code. The 74L5138 outputs are buffered by eight 1802, common collector pnp transistors Q7-Q14. This provides a single-digit current-sinking ability of 98 ma (14 ma per segment×7). The decimal point is driven directly from the 82C55, with the drive signal buffered by a 1402 NPN follower transistor Q15.
RSM Firmware
The purpose of the meter firmware is to control the meter hardware and to accumulate energy consumption which can be read by either the built in display or by power line carrier communication. Broadly, the program is divided into two parts, the energy meter and the power line carrier communications. Appendix I is a source listing of this program.
Energy Meter
The energy meter firmware performs two basic functions--sequencing the hardware and calculating the energy.
Referring to FIG. 10, the sequencing of the meter is as follows. This sequence of operations is performed for each voltage and current "phase-pair" that is switched through into the metering circuitry. Referring back to FIG. 10, first the non-inverting input of amplifier U2A is zeroed by central processor-controlled switching of multiplexer U1 to its grounded pin 11 input. U2B is then set to maximum gain when the microprocessor switches U4 to the lowest resistor of an eight-resistor voltage divider circuit R19-R26 that provides U4 with its inputs. The maximum gain setting provides maximum offset voltage and the resulting output is switched through pin 3 of switch U7A into an auto-zero circuit, built around integrator U11. The output of U11 is summed into input pin 3 of U2B through a divider composed of R33 and R30. While U7 is switched to its pin 3 input the integrator loop drives the output of U2B toward the input offset voltage of the integrator. When U7 is switched to its pin 5 (grounded) input at the end of the zeroing the integrator holds its output voltage. In this way, the auto-zero integrator compensates for the U2 amplifier offset over several zeroing cycles.
With the zeroing functions complete, the processor selects the phase and the appropriate gain for the current input. This setting is based on the history of current input for the given phase and is retained and updated in RAM.
After allowing for amplifier settling time, the current signal is held in capacitor C1 of sample-and-hold circuit U5 and then routed sequentially with the voltage sample through the V-I MUX into the ADC circuit.
The next phase of inputs is then selected, and the preceding sequence of operations is repeated.
The calculation of the energy is as follows. The sequencing of the metering circuit produces a pair of 8 bit readings per phase. These numbers correspond to the physical quantities of current and voltage. The relation of the number produced by the ADC to the physical units depend upon the signal path from source to ADC. For the voltage there are three paths corresponding to the three different phases. For current there are 24 paths corresponing to 8 ranges for each of 3 phases. The ADC produces a number from 0 to 255. The relationship between the magnitude of the number measured by the ADC and physical units is the scale factor. The scale factor is different for each of the signal paths. The number corresponding to zero volts or amps is the offset.
The scale factors for current depends on the current transformer, C.T., the range of the adjustable gain amp U2,the tolerance of the gain determining resistors used in the meter circuit and the ADC. The scale factor for voltage depends only on resistor values and on the gain of the ADC. Because the final measured quantity is energy, the scale factor of each sampled energy unit is the product of the scale factors of the voltage and current and the sampling time interval.
The samples of voltage and current are multiplied, corrected for offset, and accumulated in a 16 bit multiplicaton - accumulation register. There are 24 multiplication registers, one for each range and phase. An overflow from any of these accumulation registers represents a quantity of energy.
This amount of energy is different for each phase and range.
A 24 entry table of 6 digit BCD numbers called the calibration constants records the energy in kilowatt hours corresponding to an overflow from the corresponding 24 multiplication accumulation registers. These constants are programmed into the ROM of the RSM at the time of manufacture by comparison of the RSM under test to a standard Watt-hour meter on each phase and range for a period of time. These constants represent the actual scale factor of the RSM on that phase and range corrected for any errors in the resistors, current transformers, ADC reference, or sampling time interval. By calibrating the meter in this way, relatively imprecise components can be used and yet produce a precise instrument. In practice the calibration constants for any phase or range vary by up to 10%, yet the calibrated meter is better than 1% accurate. This ten-fold increase in accuracy would be expensive to achieve by the conventional means of using more accurate components.
Every time there is an overflow from any of the 24 multiplication accumulation registers, the program adds the appropriate 6 digit calibration constant to the total energy register. The total energy register is a 14 digit kilowatt hour register. The top 8 digits of the energy accumulator register are stored in the NOVRAM and can assume the values from 00000.000 to 99999.999 kilowatt hours.
The offset correction is done at the time of each multiplication, yet the offset used is not the nominal value of 128 but a value calculated by the meter program. This method achieves very good meter "balance" or insusceptibility to accumulating energy in the absence of applied power. For the purpose of the offset calculation the samples are divided into groups of 32768. For the first group of 32768 samples the nominal offset is used. During this time, the average current and voltage are calculated. Because the average current and voltage measured over 32768 samples should be zero (128 on the ADC), this average is equal to the offset. During each subsequent group of 32768 samples the program uses the calculated offset of the previous 32768 samples.
The preferred program calculates the sampled power as
P=VI-O.sub.V O.sub.I
Where
O V is the offset of the voltage and
O I is the offset of the current, instead of
P=(V-O.sub.V) (I-O.sub.I).
The preferred formula yields the energy corrected for offset when the power increments calculated in this manner are summed up. Effectively, in the preferred formula the VI term is total power and the O V O I is offset power.
The current transformers have time delays which are large enough to cause inaccuracy if not corrected. The meter corrects for the time delay of a nominal C.T. by sampling the current slightly ahead of the voltage. C.T.s have different time delays depending on the magnitude of the primary flowing current. To account for this, the meter delays a different amount depending upon the range.
When selecting the range for a particular phase the meter uses the history of the current. The microprocessor software implements "fast-attack, slow decay" AGC circuit. The meter changes to a lower gain setting immediately upon recognizing an out of range current. However, the meter does not select a higher gain unless too little current has been flowing for 43 consecutive samples. The meter stays on a particular range as long as the peak current value is within particular limits. During a time when a constant load current is flowing some individual samples would necessarily be close to zero in magnitude because the input waveform is AC. The meter uses the "fast-attack, slow-decay" AGC method because ranging for individual samples would upset the time delay compensation mentioned above.
This concludes the important features of the meter energy calculation firmware.
Communications Firmware
The communications firmware controls the power line carrier hardware, sends and receives data to and from the CIP, and counts and/or latches, external pulses and/or contact closures.
The alarm and tamper inputs, described hereinabove, are read and stored in NOVRAM. Any alarm condition is latched and stored in the status word, also in NOVRAM.
"Gasmeter" input negative edges are counted in BCD and stored in NOVRAM.
Receive Functions
The serial data output of the carrier current receiver, derived as described hereinabove, is tested for an 8 bit edgeword. Once an edgeword is identified, the processor tests for a valid command. If an edgeword and valid command are not identified in 256 bits (the longest command is 36 bits including edgeword), the microprocessor switches channels by changing the divide code of U31 in FIG. 13 as described hereinabove. Thus, channels with data destroying interference are skipped. When there are no CIP transmissions, i.e., there is no valid data on the line, the RSM will channel scan continuously.
When the RSM changes channels, or is restarted from an "insane" or power up Reset, or there is a power failure as described hereinabove, the program increments one of three 4-bit counters in the NOVRAM status word, to record the fact that one of those three events occurred.
There are eight valid numerical commands that may be sent from the CIP to the RSM (0-7). If the command is "0", "2"or "3"the RSM will unconditionally perform the functions required by the command. If the zero command is received, the 12 bit address sent by the CIP is stored in RAM. When either a "1", "4", "5", "6"or "7"command is received, the above address is compared with the RSM's own address which is permanently stored in EPROM and unique in a given system. If the comparison fails, the command is ignored and the microprocessor restarts the 256 bit count, as above, without changing channels. If the addresses match, the RSM will perform the functions required by the command.
If a command requires a reply, the RSM will turn on the transmitter as described hereinabove and disable the display for the duration of the transmission, thereby reducing peak drain from the power supply.
The "4" command has a 4 bit argument which can specify a variety of actions. The "4 - 1" command causes the RSM to select the current kilowatt hour reading for future transmission. The "4 - 2" command similarly causes the RSM to select the external (Gasmeter) count and the "4 - 7" command similarly causes the RSM to select the NOVRAM area containing the status word, display flag, data clock buffer, and the calibrate/meter/install flag buffer. When restarted from reset, the microprocessor examines the latter flag buffer and chooses to run the calibrate program (used only for factory calibration) or the meter program. If the install flag is set and a "3" command is received, the RSM will send its address. If the install flag is not set, the "3" command is ignored. The install flag can be set at the factory. To set it in the field, all the external inputs accessable on TB3 must be shorted to ground while a "4 - 5" command is received. The "4 - 3" command resets the install flag regardless of the state of the above inputs. The "4 - 4" command resets the status word. The "4 - 0" command disables the display button and the "4 - C" enables it. When it is enabled, pushing the display button results in a 10-second display of the kilowatt hour data. The display button must be released and pushed after timeout to obtain another ten seconds of display. The "4 - E" command sets the data clock to normal phase and the "4 - F" command inverts it. This feature allows the CIP to maximize the number of RSMs on a single polling data clock as is set forth hereinbelow.
The "2" command causes all RSMs to format for transmission the data selected by the "4" command as hereinabove described and stores it in an output buffer. The "6" command causes the currently addressed RSM to transmit the contents of the abovementioned output buffer.
The "1" command causes all RSMs to increment by one the address received and stored in the "0" command described hereinabove. The RSM with an address match responds as in command "6", above.
The "5" command causes the currently addressed RSM to transmit the contents of the status word which is described hereinabove.
The "7" command works as described in the "5" command except that both the RSM's own address and the status word are sent.
This concludes the important features of the communications firmware.
COMMUNICATION INTERFACE PROCESSOR (CIP)
Refering to FIG. 19 there is shown a block diagram of the Communications Interface Processor of the remote metering system. The basic elements of the CIP are a standard telephone modem 1010, a Central Processing Unit CIP-CPU 1020, a Power Line Carrier PLC unit 1040 and a Phase Coupling Module PCM 1060. The standard telephone modem 1010 is used for communiaations between the CIP and the central billing computer and may be for example a Signalman Mark VII standard 300 baud modem from Anchor Automation Inc. Van Nuys, Calif. The CIP - CPU 1020 is the stored program microprocessor based master control unit of the CIP which under program - control transmits and receives information to and from the RSMs through the PLC unit 1040; transmits and receives information to and from the central billing computer through the telephone modem 1010; stores information; and stores the date and time of day. The Power Line Carrier 1040 employs a unique interference resistant transmitting and receiving system for communications over the a.c. power lines between the CIP - CPU and the RSMIS. The Phase Coupling Module 1060 of the illustrative embodiment is inductive/capacitive coupled to the a.c. power line and is capable of coupling the data transmission from and to the RSM over any phase of the a.c. power line. A detailed description of the PCM is given in the AC line interface section of the RSM description hereinabove. The CIP of the illustrative embodiment is capable of reading, storing data from, and monitoring 4096 RSM units.
Referring to FIG. 20 there is shown a block diagram of the CIP - CPU. Microprocessor 1021 is clocked by clock 1027 and executes program instructions stored in ROM 1025. In the illustrative embodiment the microprocessor is a standard 8 bit unit such as the Model 8085 manufactured by Intel Corporation Santa Clara, Calif. Microprocessor 1021 has a data bus 1026 over which data is exchanged among Time of Day unit 1022, RAM 1028, Parallel I/O port 1024 and Serial I/O port 1023. Program instructions from ROM 1025 are also passed to microprocessor 1021 on data bus 1026. A listing of the program instructions for controlling the CIP-CPU of the illustrative embodiment is given in Appendix II. This program controls the microprocessor in such a manner that the functions of CIP are performed. The program has two major functional divisions, a communications function and a monitor/housekeeping function. These functions are identified in as the XMIT Routine Version 2.0 and CIPMON Version 2.6 respectively.
The XMIT Program is called by CIPMON and directs the microprocessor control of communications with the RSMs on the CIP network. In the illustrative embodiment the central billing computer directs the execution of CIPMON by commuication with the microprocessor through the telephone modem 1010 and the serial I/O port 1023. The specific communication is determined by one of seven numbered commands and a `0` command which are selected and delivered over data bus 1026 to parallel I/O port 1024 and transmitted to the RSMs by PLC 1040.
The `0` command sends a 12 bit current address selected at the central computer site to all of the RSMs. As is more fully explained hereinabove, each RSM is assigned and permanently stores its own unique 12 bit address code. When the RSM receives the 12 bit address transmitted by the `0` command that address is stored. When either a `1`, `4`, `5`, `6` or `7` command is received that address is compared with the RSMs unique address. If they are the same, the RSM transmits the indicated response over the noise free channel selected in accordance with the description hereinabove.
The `1` command causes all of the RSMs to increment by `1` the address received and stored upon receipt of the `0` command. The RSM with the 12 bit address corresponding to this incremented address then responds with its address and the kilowatt hour reading stored in its output buffer.
The `2` command causes all of the RSMs to store in their output buffer the current value of the measured quantity as selected by the "4" command, described hereinabove, which had been previously stored in its memory in the manner described hereinabove.
The `3` command is used during initial installation of RSMs for tests which ensure that the system has been properly installed.
The `4` command is a set status command. This command has a four bit argument that causes the RSM to either select kilowatt hour meter data; or select setable switch or pulse input data; or reset the install flag; conditionally set install flag; or reset the status register; or disable the display; or enable the display; or read flags from a register; or set data clock phase.
The `5` command is a read status command. This command causes the currently addressed RSM to respond with the contents of its status register. This register contains the status of the currently addressed RSM which was either set by a `4` command or set in accordance with the description herein above.
The `6` command causes the currently addressed RSM to transmit the contents of its output buffer.
The `7` command causes the currently addressed RSM to transmit its status and address.
The foregoing is a brief description of command and data communication functions performed by the microprocessor 1021 under direction of the XMIT Routine.
The CIPMON routine is the monitor or executive program of the CIP. This routine directs microprocessor 1021 to execute all of the tasks performed by the CIP that are not performed by the XMIT program. For example, CIPMON controls all access to RAM 1028; obtains the date and time from Time of Day device 1022; and supervises communications through I/O ports 1023, 1024.
Referring to FIG. 21 there is shown a block diagram of CIP - PLC unit 1040. The CIP - PLC is a single channel, single sideband version of the RSM - PLC shown in FIG. 4 and described hereinabove. In this version, one channel of data to be transmitted to the RSMs is sent by CIP - CPU 1020 to the CIP - PLC through parallel I/O port 1024. This data stream is input to six identical Frequency Shift Keying transmitters 1051 - 1056. The output of these transmitters is summed in summer 1048 and the summed signal is transmitted over the a.c. power lines through PCM 1060. A transmit enable relay 1058 is provided so that data is transmitted only when CIP - CPU 1020 applies the appropriate signal to the XMIT/REC control line 1050. The transmitters 1051-1056 of the illustrative embodiment are designated channels 1-6 and transmit mark (`1`) and space (`0`) at the frequencies shown in TABLE I. Because all data transmissions are encoded in a manner recognized by the RSM, it will be seen that the transmission of the identical data over all six channels enables the RSM to identify a particular channel that is not subject to interference as is described in more detail hereinabove.
Raw clock generator 1059 provides a 60 hz data clock for synchonization of transmitted and received data. This generator is essentially the same as that described hereinabove and shown in FIG. 9.
The inputs of Frequency Shift Keying Receivers 1041-1046 are connected to a 30-50 khz Bandpass filter which in turn is connected to PCM 1060. The outputs of these receivers are connected to the parallel I/O port 1024 of the CIP-CPU 1020. Thus, no matter which channel is chosen by the RSM the received data is transferred to the CIP - CPU 1020.
TABLE I______________________________________CHANNEL MARK FREQ SPACE FREQ______________________________________1 31475 315252 33558 336083 35939 359894 38687 387375 41892 419426 45680 45730______________________________________
FIGS. 22-35 are detailed schematic diagrams of the circuits of the Communication Interface Processor of the illustrative embodiment.
Referring to FIG. 22, there is depicted the Master CPU and clock of the CIP. Clock generator U79 supplies an 8 MHz clock to CPU U1, illustratively an NSC 800 type device manufactured by National Semiconductor.
The decoding circuitry of the CIP (FIG. 23) provides decoding for the CIP. Address lines A13, A14 and A15 are each inverted by inverters U18 and input to NAND gate U19 to provide memory control signal ROMCS. Memory read, ROM read and I/O read signals are produced by three NAND gates U17. Memory write signal MWRT is produced by OR gate U25 and inverter U18 and 1/0 write signal IOWR is produced by OR gate U25.
Referring to FIG. 24, the buffer address lines to LOC of the CIP are depicted. Buffering is accomplished through U80 and U81, each of which comprises eight buffers. The output lines of buffers U80, U81 are input to RAM/IO.
The parallel I/O circuitry of the CIP (FIGS. 25A, 25B) comprises three I/O chips U62, U63 and U73, each an 8255 type device. Control signals RD and WR of U62, U63 and U73 provide for reading from memory and writing to memory while the data is applied to eight-bit line D0-D7 of U62, U63 and U73.
FIG. 26 depicts the insane and power fail circuits of the CIP. Operation of the insane and power fail circuits of the CIP are depicted in FIG. 26 corresponds to operation of the insane and power fail circuits of the RSM depicted in FIGS. 5 and 15 and the accompanying descriptions. The insane circuit protects against CPU failure while the power fail circuit identifies incipient power failure.
Additional buffer circuitry of the CIp is shown in FIGS. 27, 28. These buffers are used for the data passed through the parallel I/O circuitry of FIGS. 25A, 25B. Buffers U27, U26, U5 and U4 are Fairchild 74LS244 line driver/buffer type devices.
Referring to FIG. 29, there is depicted a schematic diagram of the clock back up circuit of the CIP.
FIGS. 30A, 30B is a schematic diagram of the serial interface ports and RS232 buffers of the CIP. I/O devices U64, U65, and U66 are each 8250 type devices manufactured by National Semiconductor and are connected to address and data lines of memory to provide for input and output of data.
The input/output, random access memory, read only memory and data bus circuitry of the CIP is depicted in the schematic of FIGS. 31A, 31B. ROM device U28 is illustratively an Intel 2764 type device which has its data lines D0-D7 tied to data lines D0-D7 of RAM U291. Similarly, address lines A0-A10 of U28 are tied to address lines A0-A10 of U291. Signals RD and WR of RAM 291 provide for reading and writing of data. Decoder/demultiplier U20 is a 74HS138 type device while decoders/demultiplexers U21, U22 and U23 are HC138 type devices.
Referring to FIG. 32, the master address bus of the CIP comprises eight-bit, D-type, transparent latch U3 of the 74LS373 type manufactured by Fairchild which is enabled via signal ALE on latch enable pin 11 and bus driver/buffer U2 of the 74LS244 type.
FIG. 33 depicts the master status circuitry of the CIP comprising decoder U6 and inverting line driver/buffer U7. Decoder U6 supplies control signals INP, OUT, HALT, MI, MEMRD and MEMWR to buffer 240 which outputs the corresponding inverted control signals.
The disc controller circuit of the CIP is shown in FIG. 34 and comprises disc controller U74 which is illustratively a 1770 type device manufactured by SGS Semiconductor, inverting line driver/buffer U76 and line driver/buffer U73. Header 34 is supplied with control signals from U73, U74 and U76 and outputs these signals to a disc drive (not shown).
Referring to FIG. 35, there is shown the master control and utility circuitry of the CIP, comprising inverting bus driver/buffer U9 illustratively type LS240, bus driver/buffer U10 illustratively type LS244, Schmitt trigger U11 illustratively type LS14 and two D-type flip flops U13 illustratively type LS74, all manufactured by Fairchild.
While the invention has been described with reference to a specific illustrative embodiment, it will be apparent to those skilled in the art that variations and substitutions may be made which are within the scope of the appended claims. | A method and apparatus are disclosed for sensing, sampling and performing calculations on a parameter of a physical quantity at a plurality of remote locations comprising a plurality of remote sensing units and at least one processing unit linked to said plurality of remote sensing units via a two way communication link. Parameters of a physical quantity are sensed and sampled, calculations are performed and accumulated and transmitted, on demand, provided to the processing unit using a plurality of frequency bands one of which is identified as having valid data. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an improved wall tie for a veneer anchoring system for use in conjunction with a wall structure having an inner wythe and an outer wythe, and, more particularly, to construction techniques for embedding low profile wire formatives in the bed joints of the inner and outer wythes having an interlocking arrangement between the wall tie and an inner wythe anchor. One aspect of the invention is to provide the anchoring of an outer wythe of brick or masonry veneer to an inner wythe of masonry block or drywall construction.
2. Description of the Prior Act
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. On the other hand, contractors find that heavy-wire anchors, with greater diameters, frequently result in misalignment and look towards substituting thinner gage wire formatives. Such substitution thereby facilitating alignment of courses.
In the past, there have been investigations relating to the effects of various forces, particularly lateral forces, upon brick veneer construction having wire formative anchors embedded in the mortar joint of anchored veneer walls. The seismic aspect of these investigations were referenced in the first-named inventor's prior patent, namely U.S. Pat. Nos. 4,875,319 and 5,408,798. Besides earthquake protection, the failure of several high-rise buildings to withstand wind and other lateral forces has resulted in the incorporation of a requirement for continuous wire reinforcement in the Uniform Building Code provisions. The first-named inventor's related Seismiclip R and DW-10-X R products (manufactured by Hohmann & Barnard, Inc., Hauppauge, N.Y. 11788) have become widely accepted in the industry. The use of a wire formative anchors in masonry veneer walls has also demonstrated protectiveness against problems arising from thermal expansion and contraction and has improved the uniformity of the distribution of lateral forces in a structure. However, these investigations do not address the mortar layer thickness vs. the wire diameter of the wire formative or technical problems arising therefrom.
The following patents are believed to be relevant and are disclosed as being known to the inventor hereof:
Patent
Inventor
Issue Date
3,377,764
Storch
04/16/1968
4,021,990
Schwalberg
05/10/1977
4,373,314
Allan
02/15/1983
4,473,984
Lopez
10/02/1984
4,869,038
Catani
09/26/1989
4,875,319
Hohmann
10/24/1989
It is noted that 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 interior and/or exterior wythe. Several of the prior art items are of the pintle and eyelet/loop variety.
U.S. Pat. No. 3,377,764—D. Storch—Issued Apr. 16, 1968
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.
U.S. Pat. No. 4,021,990—B. J. Schwalberg—Issued May 10, 1977
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.
U.S. Pat. No. 4,373,314—J. A. Allan—Issued Feb. 15, 1983
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.
U.S. Pat. No. 4.473.984—Lopez—Issued Oct. 2, 1984
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.
U.S. Pat. No. 4,869,038—M. J. Catani—Issued Sep. 26, 1989
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.
U.S. Pat. No. 4,879,319—R. Hohmann—Issued Oct. 24, 1989
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.
None of the above provide the masonry construction system for an inner masonry wythe and an outer facing wythe with low-profile wire formative wall ties as described hereinbelow.
SUMMARY
In general terms, the invention disclosed hereby includes a veneer anchoring system incorporating a low-profile wall tie for use in the construction of a wall having an inner wythe and an outer facing wythe. The wythes are in a spaced apart relationship and form a cavity therebetween. In the first two embodiements disclosed, a unique combination of a wall anchor and a low-profile wall tie member is provided. The invention contemplates that the primary components of the system are reinforcing wire and wire formatives, such as truss reinforcement or ladder mesh reinforcements, providing wire-to-wire connections therebetween.
In third embodiment, the invention disclosed hereby includes a veneer anchoring system incorporating a low-profile wall tie for use in the construction of a wall having an inner dry-wall wythe and an outer facing wythe. The wythes are in a spaced apart relationship and form a cavity therebetween. In this embodiment, a unique combination of a wall anchor and, a low-profile wall tie member is provided. The invention contemplates that the primary components of the system are veneer anchors, as described in U.S. Pat. Nos. 4,021,990 and 4,598,518 and wire formative wall ties providing a positive interlocking connection therebetween.
In the mode of practicing the invention, wherein the inner wythe is constructed from a masonry block material, the masonry anchor has, for example, a truss portion with eye wire extensions welded thereto. The eye wires extend into the cavity between the wythes. Each eye wires accommodates the threading thereonto of a wire wall tie through the open end of the wall tie. The wall tie is then positioned so that the open end is utilizable as part of the facing wall tie. The masonry anchor is embedded in a bed joint of the interior wythe. The facing wythe is anchored by mounting in bed joints of the exterior wythe the open end of the low-profile wire formative wall tie. The low-profile permits the mortar of the bed joint to flow over and about the insertion end of the wall tie and secure the tie to the outer wythe. Because the eye wires have sealed eyelets and the open ends of the wall ties are sealed in the joints of the exterior wythes, a positive interengagement results.
In the mode of practicing the invention, wherein the inner wythe is a dry wall construct, a dry wall anchor, which is a stamped metal unit, is attached by sheetmetal screws to the metal vertical channel members of the wall. Each wall anchor accommodates in an opening therethrough the threading of a low-profile wire formative wall tie. As in the case of the masonry inner wythe, the open end of the wall tie is then positioned so that the open end is utilizable as part of the insertion end of the facing wall tie. The facing wall tie has a compressibly reduced in height and is mounted along the exterior wythe to receive the open end of wire wall tie with each leg thereof being placed adjacent one side of reinforcement wire. The low-profile of the facing wall tie is embedded in a bed joint of the exterior wythe. Because the dry wall anchor opening is a closed loop and the open ends of the wall ties are sealed in the joints of the exterior wythes, a positive interengagement results.
OBJECTS AND FEATURES OF THE INVENTION
It is an object of the present invention to provide in a wall structure having a facing wythe and a inner wythe, a veneer anchor system which employs a low-profile wire formative in the mortar joint of the facing wythe and is positively interconnected with a wall anchor attached to the inner wythe.
It is another object of the present invention to provide labor-saving devices to aid in the installation of brick and stone veneer and the securement thereof to an inner wythe.
It is yet another object of the present invention to provide a low-profile anchor system which ties to the continuous wire reinforcement of the inner wythe in a manner such that the mortar layer thickness in the facing wythe is readily maintainable.
It is a further object of the present invention to provide a low-profile anchor system comprising a limited number of component parts that are economical of manufacture resulting in a relatively low unit cost.
It is yet another object of the present invention to provide a veneer anchor system which is easy to install and is highly resistant to being pulled out of the mortar layer.
It is a feature of the present invention that the portion of the wall tie embedded in the joint of the facing wythe has a pattern impressed thereon.
It is another feature of the present invention that the wall tie is dimensioned with a sufficiently low profile so that, when inserted into the mortar layer, the mortar thereof can flow around and into the low-profile wall tie.
Other objects and features of the invention will become apparent upon review of the drawings and the detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
In the following drawings, the same parts in the various views are afforded the same reference designators.
FIG. 1 is a perspective view of a first embodiment of a low-profile, wall tie of this invention and shows a wall with an interior wythe of masonry block and an exterior wythe of brick, with selected aligned bed joints and utilizing aforesaid wall tie;
FIG. 2 is a partial perspective view of FIG. 1 showing the wall anchor and the low-profile, wall tie;
FIG. 3 is a partial perspective view of the wall tie of FIG. 2 showing the corrugated pattern thereof;
FIG. 4 is a perspective view of a second embodiment of a low-profile wall tie, similar to FIG. 1, but employing a ladder-type reinforcement in the interior wythe and a low-profile, rectangular pintle wall tie in the exterior wythe without aligned bed joints;
FIG. 5 is a partial perspective view of FIG. 4 showing a portion of the wall anchor and the low-profile wall tie;
FIG. 6 is a partial perspective view of the wall tie of FIG. 5 showing the cellular pattern thereof;
FIG. 7 is a perspective view of a third embodiment of a low-profile wall tie, similar to FIG. 1, but employing a dry wall anchor in the interior wythe and a low-profile, V-type wall tie;
FIG. 8 is a partial perspective view of the wall tie of FIG. 7 showing the dry wall anchor and a low-profile, V-type wall tie; and,
FIG. 9 is a partial perspective view of FIG. 8 showing the raised diamond non-slip pattern thereof.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to FIGS. 1 to 3 , the first embodiment of a low-profile wall tie device of this invention is shown and is referred to generally by the numeral 10 . In this embodiment, a wall structure 12 is shown having an interior wythe 14 of masonry blocks 16 and an exterior wythe 18 of facing brick 20 . Between the interior wythe 14 and the exterior wythe 18 , a cavity 22 is formed. In the first embodiment, successive bed joints 24 and 26 are formed between courses of blocks 16 and the joints are substantially planar and horizontally disposed. Also, successive bed joints 28 and 30 are formed between courses of bricks 20 and the joints are substantially planar and horizontally disposed. For each structure, the bed joints 24 , 26 , 28 and 30 are specified as to the height or thickness of the mortar layer and such thickness specification is rigorously adhered to so as to provide the uniformity inherent in quality construction. Selected bed joint 24 and bed joint 28 are constructed to align, that is to be substantially coplanar, the one with the other. For purposes of discussion, the exterior surface 32 of the interior 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 also passes through the coordinate origin formed by the intersecting x- and y-axes. In the discussion which follows, it will be seen that the various anchor structures are constructed to restrict movement interfacially—wythe vs. wythe—along the z-axis and, in this embodiment, along the y-axis. The system 10 includes a masonry anchor 40 constructed for embedment in bed joint 24 and a facing anchor 42 constructed for embedment in bed joint 28 , including a low-profile, wire formative wall tie member 44 .
The masonry anchor 40 is shown in FIG. 1 as being emplaced on a course of blocks 16 in preparation for embedment in the mortar of bed joint 24 . In the best mode of practicing the invention, a truss or reinforcement wire portion 46 is constructed of a wire formative with two parallel continuous straight wire members 48 and 50 spaced so as, upon installation, to each be centered along the outer walls of the masonry blocks 16 . An intermediate wire body or wire 52 is interposed therebetween and connects wire members 48 and 50 forming chord-like portions of the truss 46 . At intervals along the truss 46 , spaced pairs of transverse wire members 54 are attached thereto and are attached to each other by a rear leg 56 therebetween. These pairs of wire members 54 extend into the cavity 22 . As will become clear by the description which follows, the spacing therebetween is constructed to limit the x-axis movement of the construct. Each transverse wire member 54 has at the end opposite the attachment end an eye wire portion 58 formed continuous therewith. A sheetmetal loop is an alternative construction in lieu of eye wires shown in the best mode; however, the wire formative has been found to be structurally superior. Upon installation, the eye 60 of eye wire portion 58 is constructed to be within a substantially vertical plane normal to exterior surface 32 . The eye 60 is dimensioned to accept a wall tie threadedly therethrough and is thus slightly larger than the diameter of the tie. This relationship minimizes the y- and z-axis movement of the construct. For positive engagement, the eye 60 of eye wire portion 58 is sealed forming a closed loop.
The wall tie 44 is generally rectangular in shape and is dimensioned to be accommodated by a pair of eye wires 58 previously described. The wall tie 44 has a rear leg portion 62 , two parallel side leg portions 64 and 66 , and two front leg portions 68 and 70 . The front leg portions 68 and 70 are spaced apart at least by the diameter of the wire member 54 . An insertion portion 72 of wall tie 44 , upon installation, extends beyond cavity 22 into bed joint 28 , which portion includes front leg portions 68 and 70 and part of side leg portions 64 and 66 adjacent to front leg portions 68 and 70 . The longitudinal axes of leg portions 62 , 64 , 66 , 68 and 70 are substantially coplanar. The side leg portions 64 and 66 are structured to function cooperatively with the spacing of transverse wire members 54 to limit the x-axis movement of the construct.
The insertion portion 72 is considerably compressed and, while maintaining the same mass of material per linear unit as the adjacent wire formative, the vertical height 74 is reduced. The insertion end of the facing wall tie is a wire formative formed from a wire having a diameter substantially equal to the predetermined height of the mortar joint. Upon compressible reduction in height, the insertion end of the facing wall tie is mounted upon the exterior wythe positioned to receive mortar thereabout. The insertion end of the facing wall tie, usually the open end of wire wall tie, retains the mass and substantially the tensile strength as prior to deformation. The vertical height 74 of insertion portion 72 is reduced so that, upon installation, mortar of bed joint 28 flows around the insertion portion 72 . Upon compression, a pattern or corrugation 76 is impressed on insertion portion 72 and, upon the mortar of bed joint 28 flowing around the insertion portion, the mortar flows into the corrugations 76 . For enhanced holding, the corrugations 76 are, upon installation, substantially parallel to x-axis 34 . In this embodiment, the pattern 76 is shown impressed on only one side thereof; however, it is within the contemplation of this disclosure that corrugations or other patterning could be impressed on other surfaces of the insertion portion 72 . With wall tie 44 constructed as described, the wall tie is characterized by maintaining substantially all the tensile strength as prior to compression while acquiring a desired low profile.
The description which follows is of a second embodiment of the low-profile wall tie device. For ease of comprehension, where similar parts are used reference designators “100”, units higher are employed. Thus, the wall tie 144 of the second embodiment is analogous to the wall tie 44 of the first embodiment. Referring now to FIGS. 4 to 6 , the second embodiment of a masonry construction system of this invention is shown and is referred to generally by the numeral 110 . As in the first embodiment, a wall structure 112 is shown having an interior wythe 114 of masonry blocks 116 and an exterior wythe 118 of facing brick 120 . Between the interior wythe 114 and the exterior wythe 118 , a cavity 122 is formed. Successive bed joints 124 and 126 are formed between courses of blocks 116 and the joints are substantially planar and horizontally disposed. Also, successive bed joints 128 and 130 are formed between courses of bricks 120 and the joints are substantially planar and horizontally disposed. Selected bed joint 124 and bed joint 128 are constructed to be interconnected utilizing the construct hereof; however, the joints 124 and 128 are unaligned. For purposes of discussion, the exterior surface 132 of the interior 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 also passes through the coordinate origin formed by the intersecting x- and y-axes. The system 110 includes a masonry anchor 140 constructed for embedment in bed joint 124 and, a facing anchor 142 constructed for embedment in bed joint 128 , including a low-profile wall tie member 144 .
The masonry anchor 140 is shown in FIG. 4 as being emplaced on a course of blocks 116 in preparation for embedment in the mortar of bed joint 124 . In this embodiment, a ladder type reinforcement wire portion 146 is constructed of a wire formative with two parallel continuous straight wire members 148 and 150 spaced so as, upon installation, to each be centered along the outer walls of the masonry blocks 116 . An intermediate wire body or a plurality of wires 152 are interposed therebetween and connect wire members 148 and 150 forming rung-like portions of the ladder-type reinforcement 146 . At intervals along the ladder-type reinforcement 146 , spaced pairs of transverse wire members 154 are attached thereto and are attached to each other by a rear leg 156 therebetween. These pairs of wire members 154 extend into the cavity 122 . The spacing therebetween limits the x-axis movement of the construct. Each transverse wire member 154 has at the end opposite the attachment end an eye wire portion 158 formed continuous therewith. Upon installation, the eyes 160 of eye wire portion 158 are constructed to be within a substantially horizontal plane normal to exterior surface 132 . The eyes 160 are horizontally aligned to accept the pintles of a wall tie threaded therethrough from the unaligned bed joint. The eyes 160 are slightly larger than the diameter of the pintles, which dimensional relationships minimize the x- and z-axis movement of the construct. For ensuring engagement, the pintles of wall tie member 144 are available in a variety of lengths.
The low-profile wall tie or wire formative wall tie 144 is, when viewed from a top or bottom elevation, generally U-shaped and is, when viewed from right or left side elevation, is generally L-shaped. The low-profile wall tie 144 is dimensioned to be accommodated by a pair of eye wire portions 158 described, supra. The wall tie 144 has two rear leg portions or pintles 162 and 164 , two parallel side leg portions 166 and 168 , which are substantially at right angles and attached to the rear leg portions 162 and 164 , respectively, and a front leg portion 170 . An insertion portion 172 of wall tie 144 , upon installation extends beyond the cavity 122 into bed joint 128 , which portion includes front leg portion 170 and part of side leg portions 166 and 168 . The longitudinal axes of side leg portions 166 and 168 and the longitudinal axis of the contiguous portions of the front leg portion 170 are substantially coplanar. An insertion portion 172 of wall tie 144 , upon installation extends beyond the cavity 122 into bed joint 128 , which portion includes front leg portion 170 and part of side leg portions 166 and 168 .
The insertion portion 172 is considerably compressed and, while maintaining the same mass of material per linear unit as the adjacent wire formative, the vertical height 174 is reduced. The vertical height 174 of insertion portion 172 is reduced so that, upon installation, mortar of bed joint 128 flows around the insertion portion 172 . Upon compression, a pattern or waffle-like, cellular structure 176 is impressed on insertion portion 172 and, upon the mortar of bed joint 128 flowing around the insertion portion, the mortar flows into the cells 176 . For enhanced holding, the cells 176 are impressed on both sides of the insertion portion 172 ; however, it is within the contemplation of this disclosure that cells or other patterning could be impressed on only one surface of the insertion portion 172 . With wall tie 144 constructed as described, the wall tie is characterized by maintaining substantially all the tensile strength as prior to compression while acquiring a desired low profile.
The description which follows is of a third embodiment of the masonry construction system. For ease of comprehension, where similar parts are used reference designators “200” units higher are employed. Thus, the wall tie 244 of the third embodiment is analogous to the wall tie 44 of the first embodiment.
Referring now to FIGS. 7 to 9 , the third embodiment of the low-profile wall tie device is shown and is referred to generally by the numeral 210 . The veneer anchoring system 210 employs the pronged veneer anchor construction first described in U.S. Pat. No. 4,598,518 and marketed by Hohmann and Barnard, Inc., Hauppauge, N.Y. 11788 under the trademark “DW-10-X”. The dry wall structure 212 is shown having an interior wythe 214 with a wallboard 216 as the interior and exterior facings thereof. An exterior wythe 218 of facing brick 220 is attached to dry wall structure 212 and a cavity 222 is formed therebetween. The dry wall structure 212 is constructed to include, besides the wallboard facings 216 , vertical channels 224 with insulation layer 226 disposed between adjacent channel members 224 . The insulation layer 226 may optionally be mounted on the exterior surface of dry wall structure 212 . Selected bed joints 228 and 230 are constructed to be in cooperative functional relationship with the wall anchor described in more detail below. For purposes of discussion, the exterior surface 232 of the interior 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 also passes through the coordinate origin formed by the intersecting x- and y-axes. The system 210 includes a dry wall anchor 240 constructed for attachment to vertical channel members 224 and, a wall tie member 244 .
Reference is now directed to the construction of the wall anchor or pronged veneer anchor 240 comprising a backing plate member 246 and a projecting bar portion 248 . The projecting bar portion 248 is punched-out from the central portion of the stock plate member 246 so as to result in a centrally disposed aperture and, when viewed from the side elevation, a wall-tie-receiving slot 250 . The aperture is substantially rectangular configuration and is formed in the plate member 246 . The projecting bar portion 248 is thus disposed in substantially parallel relationship with respect to the plate member 246 ; however, the upper and lower ends of the projecting bar portion 248 are slightly angled to permit the full projection of the bar portion 248 with respect to the plate member 246 . Secured to the upper and lower ends of the plate member 246 in a substantially perpendicular relationship are pronged end members 252 which are bifurcated to form prong portions or prongs 254 . It is within the present invention to have the end members 252 formed with a single prong; however, for structural purposes of the bifurcated construction is preferred. The plate member 246 is also provided with bores 256 at the upper and lower ends thereof, the purpose and function of which will be discussed in more detail hereinbelow. As is best seen in FIG. 8, the projecting bar portion 248 is sufficiently spaced from the plate member 246 so as to form a slot 250 therebetween which is adapted to receive the wall tie 244 therewithin. In the fabrication of the dry wall as the inner wythe of this construction system 210 , the channel members 224 are initially secured in place. In this regard, the channel members 224 may also comprise the standard framing members of a building. Sheets of exterior wallboard 216 , which may be of an exterior grade gypsum board, are positioned in abutting relationship with the forward flange 258 of the channel member 224 . While the insulating layer has herein been described as comprising a gypsum board, it is to be noted that any similarly suited rigid or flexible insulating material may be used herein with substantially equal efficacy. After the initial placement of the flexible insulation layer 226 and the wallboard 216 , the veneer anchors 240 are secured to the surface of the wallboard 216 in front of channel members 224 by forcing the prongs 254 therein until the prongs 254 abuttingly engage the front flange 258 of the channel members 224 . Thereafter, sheetmetal screws 260 are inserted into the bores 256 to fasten the anchor 240 to the flange 258 and to channel member 224 .
The wall tie 244 is substantially a truncated triangularly shaped member and is dimensioned to be accommodated within slot 250 previously described. The wall tie 244 has a rear leg portion 262 , two divergent side leg portions 264 and 266 , and two parallel front leg portions 268 and 270 . To facilitate installation, the front leg portions 268 and 270 are spaced apart at least by the thickness of the projecting bar portion 248 . The longitudinal axes of leg portions 262 , 264 , 266 , 268 and 270 are substantially coplanar. The side leg portions 264 and 266 are structured to function cooperatively with the width of the projecting bar portion 248 to limit the x- and z-axis movement of the construct. An insertion portion 272 of wall tie 244 , upon installation, extends beyond the cavity 222 into bed joint 228 , which portion includes the front leg portions 268 and 270 and part of side leg portions 264 and 266 .
The insertion portion 272 is considerably compressed and, while maintaining the same mass of material per linear unit as the adjacent wire formative, the vertical height 274 is reduced. The vertical height 274 of insertion portion 272 is reduced so that, upon installation, mortar of bed joint 228 flows around the insertion portion 272 . Upon compression, a raised diamond, non-slip pattern 276 is impressed on insertion portion 272 and, upon the mortar of bed joint 228 flowing around the insertion portion, the mortar flows into the interstices diamond pattern 176 between the raised diamonds of the pattern 276 . For enhanced holding, the raised diamond pattern is shown on both sides thereof; however, it is within the contemplation of this disclosure that other patterning could be fashioned into the surfaces of the insertion portion 272 . With wall tie 244 constructed as described, the wall tie is characterized by maintaining substantially all the tensile strength as prior to compression while acquiring a desired low profile.
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. | A veneer anchoring system discloses a low-profile wall tie for use in a wall having an inner wythe and an outer facing wythe. The wythes are in a spaced apart relationship and form a cavity therebetween. A combination of a wall anchor and a low-profile wall tie member is provided. The veneer anchoring systems hereof incorporate low-profile wall ties adapted for use with a dry-wall inner wythe and for use with a masonry block inner wythe. The masonry anchor has a truss portion with eye wire extensions welded thereto. The eye wires extend into the cavity between the wythes. Each eye wires accommodates the threading thereonto of a wire wall tie through the open end of the wall tie. The wall tie is then positioned so that the open end is utilizable as part of the facing wall tie. The masonry anchor is embedded in a bed joint of the interior wythe. The facing wythe is anchored by mounting in bed joints of the exterior wythe the open end of the low-profile wire formative wall tie. The low-profile permits the mortar of the bed joint to flow over and about the insertion end of the wall tie and secure the tie to the outer wythe. Where the inner wythe is a dry wall construct, a dry wall anchor, which is a stamped metal unit, is attached by sheetmetal screws to the metal vertical channel members of the wall. | 4 |
This application is a National Stage completion of PCT/EP2012/054355 filed Mar. 13, 2012, which claims priority from German patent application serial no. 10 2011 007 390.6 filed Apr. 14, 2011.
FIELD OF THE INVENTION
The invention concerns a vehicle component having at least two connection points and a structural component that extends between the connection points and connects them rigidly to one another, which component comprises at least one insert made of a ductile material and at least two connection zones that support or form the connection points, at least one of the zones being made of plastic.
BACKGROUND OF THE INVENTION
DE 101 53 799 A1 discloses a positive-force connection strut of a chassis of a passenger vehicle or a utility vehicle for forming a connection between a chassis and a wheel carrier, which has an elongated basic body and at least two end-positioned bearing mountings for transmitting forces in and out, such that the basic body consists of at least one flat metallic insert and a plastic structure that forms the rest of the contour, which is formed by at least partial injection molding around the metallic insert. For a better connecting action between the metal and the plastic, perforations are provided in the metallic insert. Furthermore, the metallic insert can be completely surrounded by plastic.
This positive connection strut enables a weight reduction compared with purely metallic positive connection struts and also ensures that damaging the plastic body does not lead to a total loss of functionality. The metallic insert also serves to reinforce the structure in relation to service life and buckling load. Yet, the metallic insert accounts for a considerable fraction of the total weight of the positive connection strut.
SUMMARY OF THE INVENTION
Starting from there the purpose of the present invention is to enable the weight of a chassis component as discussed below.
That objective is achieved according to the invention by a chassis Component as described below.
The chassis component according to the invention, in particular one for a motor vehicle, comprises at least two connection points and a structural component that extends between the connection points and connects them rigidly to one another, the component comprises at least one insert made of a ductile material (ductile insert) and at least two connection zones that support or form the connection points, each or at least one of which consists of plastic, such that the structural component comprises at least one intermediate section that connects the connection zones rigidly to one another and that contains or is formed by the insert, the section being designed to be more ductile than each or at least one of the connection zones and, in relation to mechanical overloading of the structural component, forming a locally delimited weak-point.
The invention is based on the provision of a “locally delimited weak-point” in the structural component and thus on a different approach from that of DE 101 53 799 A1, according to which the metallic insert serves to “reinforce” the basic body and therefore extends over the full length of the same in all the embodiments shown therein. In particular the chassis component according to the present invention fulfills the requirements for use in the vehicle according to specification even without a metallic reinforcing insert in the connection zone or zones that consist of plastic. The at least one connection zone or zones of the structural component that consist(s) of plastic is/are of such dimensions that the operating forces and torques occurring during normal operation of the vehicle can be transferred without a metallic reinforcing insert. The intermediate section and/or the ductile insert are in particular only deformed when out-of-the-ordinary mechanical loads and/or torques occur (mechanical overloading), which do not yet lead to a destruction of the at least one connection zone or zones that consist of plastic. Thus, compared with the metallic insert according to DE 101 53 799 A1, the ductile insert can be made relatively short or locally delimited. Preferably, the ductile insert only extends over part of the structural component, the length of the ductile insert preferably being shorter or substantially shorter than the overall length of the structural component. In this way the weight of the chassis component can be kept relatively low. The at least one connection zone or zones that consist of plastic is/are preferably free or largely clear of the ductile insert and/or from any other metallic reinforcing insert, so that there is greater freedom in the design of the structural component. In particular, the intermediate section is located between the connection zones. Advantageously, the connection zones form end sections of the structural component. The connection points are preferably connection points at the ends of the chassis component.
Since the plastic used for the at least one connection zone or zones that consist of plastic shows brittle fracture behavior or fracture behavior with no residual deformation, a mechanical overload of the connection zone or zones would result in fracture and thus to a complete failure of the function of the chassis component. The intermediate section is, in particular, designed so that in the event of a mechanical overload of the structural component, the ductile insert deforms before a fracture of the at least one plastic connection zone or zones can take place. Preferably, the intermediate section and/or the insert is/are (mechanically) more yielding than the at least one plastic connection zone or zones.
In particular, the insert is arranged a distance away from the connection points. Preferably, the insert is positioned between the connection points. Preferably, the connection zones are connected to the intermediate section and/or the insert a distance away from the connection points.
In special cases, for example when structural space is restricted and/or the size of the chassis component is small, it can be advantageous to integrate one or other of the connection zones in the intermediate section so that this connection zone comprises the ductile material or consists of that material. In particular, the intermediate section forms the other connection zone.
Preferably, at least one or both of the connection zones is/are substantially clear of the ductile insert. The connecting section, in which each of the connection zones is combined with the intermediate section and/or the ductile insert, is preferably smaller than the remainder of the respective connection zone, particularly in a direction that passes through the two connection points. Preferably, the connection zones are also free or substantially free from other ductile and/or metallic inserts.
The structural component forms, for example, a strut. In particular the structural component is of elongated shape. In a first variant the structural component is straight or substantially so. In a second variant the structural component is curved.
The insert is in particular straight or substantially so. Preferably, the insert is elongated. Preferably, the structural component and/or the insert extend in a longitudinal direction.
In a further development of the invention the structural component is of triangular, or else Y-shaped or U-shaped form. In this case the chassis component forms a three-point control arm. For example, the chassis component forms a wishbone or a U-shaped control arm. Wishbones are used in particular on the front axle, in the lower plane. Frequent applications for them are McPherson axles. U-shaped control arms are often used in the upper plane, for example in multiple control arm or double transverse control arm axles.
The ductile insert forms, for example, a weak-point in relation to compression loads acting in the longitudinal direction of the structural component. As a supplement or alternative, the ductile insert can form a weak-point in relation to loads acting transversely to the longitudinal direction of the structural component.
Mechanical overloading of the structural component preferably results in plastic deformation of the intermediate section. Furthermore, if the structural component is mechanically overloaded the connection zones are preferably deformed elastically, in particular exclusively elastically. For example, if the structural component is mechanically overloaded the connection zones are deformed exclusively elastically, until the position of the connection points, in particular the position of the connection points relative to one another, has changed due to a plastic deformation of the intermediate section by a predetermined permanent amount which, in accordance with a tried and tested design, is for example at least 10 mm. Advantageously, if the structural component is mechanically overloaded the plastic deformation of the intermediate section takes place earlier than a deformation of the connection zones.
In one design of the invention the plastic deformation of the intermediate section can result in a position change of the connection points relative to one another, of more than 2 mm before a permanent deformation, a crack or a fracture at a point of the structural component outside the intermediate section occurs. If the chassis component has more than two connection points, the aforesaid position change preferably takes place at least between two of the connection points before a permanent deformation, a crack or a fracture occurs at a point of the structural component that lies outside the intermediate section. If the chassis component has a plurality of intermediate sections, the sum of the plastic deformations of the intermediate sections at least in one direction can result in a position change of the connection points relative to one another, for example of more than 2 mm, before a permanent deformation, crack or fracture occurs at a point of the structural component lying outside the intermediate sections.
The ductile insert forms in particular a separate component, which is optimally adapted to its function as a weak-point. Thus, it is possible for the ductile insert to withstand plastic deformations and/or strains of more than 5%. Strains of more than 10% or more than 50% are even possible for the ductile insert before it breaks. Thus, after a mechanical overload of the structural component the chassis component remains functional to a limited extent. Moreover, owing to its severe deformation the chassis component changes the driving behavior of the vehicle to a perceptible extent so that the driver can be made aware that the chassis component has been damaged.
In a design of the invention, at least at one of its ends the insert is imbedded by injection molding in the plastic of the at least one connection zone that consists of plastic. Preferably, however, at least in its end areas the insert is injection molded into the plastic of the connection zones that consist of plastic. In particular, the ends are axial ends of the insert. If the insert is partially free, then it is preferably provided with corrosion protection. Furthermore, the insert can be completely imbedded in the plastic. In that case the intermediate section together with the at least one connection zone or the zones that consist of plastic form a uniform plastic body in which the ductile insert is imbedded in the intermediate section. The plastic can then serve to protect the ductile insert against corrosion, so that no additional corrosion protection is needed.
In a design of the invention the ductile insert is connected in an interlocking manner with the connection zones or with at least one of them which, for example, is formed by the at least one connection zone consisting of plastic. For example, the ductile insert and/or the connection zones or at least one of them have geometries that form an undercut, so that the interlock is produced by one or more undercuts. In particular, in the ductile insert one or more through-holes are provided, through which the plastic material of the at least one connection zone or zones consisting of plastic penetrates.
In the case of an interlocking connection of the ductile insert with the connection zone, it is advantageous for the weak-points to be outside the interlocking connection area, so that a deformation of the ductile insert has no, or only a slight negative effect on the durability of the interlocking connection. Preferably therefore, the weak-point is not located in the interlock area.
The circumferential contour of the ductile insert can be circular. Preferably however, the circumferential contour of the ductile insert deviates from a circular shape. In that way, due to the geometry of the insert alone the connection zones can be connected to one another with interlock in a rotationally fixed manner. For example the ductile insert can be formed by a closed or open hollow profile. Preferably, the ductile insert is formed by a U-section, which can be obtained particularly inexpensively.
The ductile insert can be formed in one piece. In a further development of the invention the ductile insert is formed with more than one part. As components of the insert, for example simple stamped parts can be used, which can be obtained particularly inexpensively. Furthermore, in that case an injected plastic can serve as a spacer between the parts of the ductile insert, for example in order to increase the buckling load.
The ductile insert preferably consists of metal. In particular the ductile insert consists of steel or aluminum. Many metals are entirely suitable for the ductile insert.
The plastic of which the at least one connection zone or zones that consist(s) of plastic is/are made, is preferably filled with fibers. The fibers serve in particular to reinforce the plastic and can therefore also be termed reinforcing fibers. For example, the plastic is filled with endless fibers. As the fibers, for example glass fibers and/or carbon fibers can be used. In particular, the plastic is a thermoplastic or a thermosetting plastic. Advantageously, the plastic is a polyamide or an epoxide resin.
The at least one connection zone or zones consisting of plastic are made in particular by the injection molding process. Preferably, during the production of the at least one connection zone or zones consisting of plastic, the plastic material is injected around the ductile insert. Each of the connection zones can be made separately. However, it is preferable for the connection zones to be produced in a combined injection molding process.
The connection points are in particular provided at the ends of the connection zones that face away from the ductile insert. Preferably, each of the connection points is formed integrally with its respective connection zone. In this way each of the connection points can be made together with its respective connection zone. In particular, the connection points together with the connection zones can be produced by an injection molding process. However, the connection points can also be made separately and subsequently joined to the connection zones.
In a design of the invention, in at least one or in each of the connection points a perforation is provided, which in particular is circular and preferably through-going. For example, at least one or each of the connection points can be in the form of a ring, a hollow cylinder or a pot. In particular, each of the connection points is in the form of a ring or cylinder. Preferably, a joint is held or formed by at least one, or by each of the connection points, which is for example in the form of a ball joint or a rubber mounting. In particular, each or at least one of the connection points forms a joint holder.
The chassis component is preferably connected at one or more of its connection points to one or more other chassis components, in particular with interposition of the, or of the respective, associated joint(s). Advantageously, the chassis component is connected at one or more other connection points, in particular with interposition of the, or of the respective associated joints, to a vehicle body structure of the motor vehicle.
In a further development of the invention a detection device is provided, by means of which a mechanical overload of the structural component can be detected. The detection device preferably comprises one or at least one electric conductor which, for example, is positioned along the ductile insert. The electric conductor is advantageously embedded in the plastic and is thus protected against impacts by stones and other environmental influences. Furthermore, the electric conductor is connected to an evaluation device of the detection device. If the ductile insert is deformed due to a mechanical overload, the electric conductor breaks or is deformed, and this can be detected by the evaluation device. A detected mechanical overload of the structural component is signaled by the detection device, preferably to one or more other devices and/or to the driver.
As a supplement or alternative, the detection device can detect a mechanical overload of the structural component by a change, attributable to deformation of the ductile insert, of the electrical properties of the ductile insert itself, particularly when the insert consists of a metal. Thus, by means of the detection device preferably at least one electrical property of the insert can be detected, which changes when the insert is deformed. In particular the detection device is electrically connected to the insert.
As a supplement or alternatively, the fibers embedded in the plastic can be used to detect a mechanical overload of the structural component, for example by making use of the optical properties of the fibers (for example in the case of glass fibers) and/or the electrical properties of the fibers (for example in the case of carbon fibers). The detection device preferably comprises fibers embedded in the plastic, whose optical and/or electrical properties are changed by mechanical loading, in particular by a mechanical overload of the structural component. The fibers used for detecting a mechanical overload of the structural component are preferably endless fibers.
If the ductile insert is made of more than one part, its parts are advantageously electrically insulated from one another. Preferably, the parts of the ductile insert are made electrically conducting. In particular, the parts of the ductile insert are connected electrically to the detection device. For example, a mechanical overload of the structural component can be detected by measuring the electric capacitance between the parts of the ductile insert. Due to a deformation of the ductile insert the distance between the parts changes and so too therefore does the capacitance change, which can preferably be detected by the detection device which, in such a case, comprises in particular a capacitance measuring device. Furthermore a mechanical overload of the structural component can be detected by monitoring the parts of the insert for electrical contact. Due to a deformation of the ductile insert its parts can come into electrical contact with one another, and this can preferably be detected by the detection device which, in such a case, contains in particular a current-measuring or resistance-measuring device.
In a further development of the invention the structural component comprises two, at least two or more than two ductile material inserts, which form weak-points in relation to mechanical overload of the structural component in different loading directions. This further development is advantageously implemented in the case of structural components having a triangular, Y-shaped or U-shaped design. The different loading directions are for example the longitudinal direction and the transverse direction of the vehicle.
The number of connection zones is preferably equal to the number of connection points. Furthermore, the number of intermediate sections is preferably smaller than the number of connection points or equal to it less one. The number of ductile inserts too is preferably smaller than the number of connection points or equal to it less one, bearing in mind that each of the ductile inserts can be made in one or more than one part.
In a design of the invention the chassis component according to the invention comprises at least three connection points, so that the structural component comprises at least two inserts of ductile material (ductile inserts) and at least three connection zones that support or form the connection points, of which some, all or at least one consists of plastic. Furthermore the structural component comprises at least two intermediate sections, such that the connection zones are connected rigidly to one another in pairs, in each case by one of the intermediate sections. Each of the intermediate sections comprises one, or at least one of the inserts and is more ductile than each, or at least one of the connection zones connected to it, so that in relation to mechanical overload of the structural component each intermediate section constitutes a locally delimited weak-point. In this design the structural component is for example triangular, Y-shaped or U-shaped.
The chassis component is for example a steering track rod or wheel guide rod. In particular the chassis component forms a transverse control arm. In a first alternative the chassis component is in the form of a two-point control arm and has two connection points. In a second alternative the chassis component is in the form of a three-point control arm and has three connection points.
BRIEF DESCRIPTION OF THE DRAWINGS
Below, the invention is described with reference to preferred embodiments illustrated in the drawing, which shows:
FIG. 1 : A very schematic side view of a chassis component according to a first embodiment of the invention,
FIG. 2 : A section through the chassis component, taken along the section line 2 - 2 shown in FIG. 1 ,
FIG. 3 : A section through the chassis component, taken along the section line 3 - 3 in FIG. 1 ,
FIG. 4 : A schematic plan view of the chassis component according to the first embodiment, with joints inserted,
FIG. 5 : A schematic plan view of a chassis component according to a second embodiment of the invention,
FIG. 6 a -6 i : Sections through the chassis component according to the second embodiment, taken along the section line 6 - 6 in FIG. 5 , wherein nine different variants of the ductile insert are shown, and
FIG. 7 : A schematic plan view of a chassis component according to a third embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIGS. 1 to 3 show different views of a chassis component 1 according to a first embodiment of the invention, in which two connection points 2 and 3 , each forming a joint holder, are connected rigidly to one another by means of a structural component 4 in the form of a strut. The structural component 4 of elongated form has a central longitudinal axis 5 and the structural component 4 is divided along its central longitudinal axis 5 into three zones. A connection zone 6 of the structural component 4 is formed in one piece with the connection point 2 , which latter forms a free end of the connection zone 6 . In addition a connection zone 7 of the structural component 4 is formed in one piece with the connection point 3 , which latter forms a free end of the connection zone 7 . Thus, the connection zones 6 and 7 form end areas of the structural component 4 . A distance away from the connection points 2 and 3 , the connection zones 6 and 7 are connected rigidly to one another by means of an insert 8 , which defines an intermediate section 9 of the structural component 4 .
The insert 8 is formed by a U-profile and provided at each axial end with respective through-holes 10 . Moreover, the insert 8 consists of a ductile material, in particular a metal. The connection zones 6 and 7 consist of plastic and the axial ends of the insert 8 have the plastic of the connection zones 6 and 7 injection molded around them, so that the plastic extends through the through-holes 10 . Thus, by means of the insert 8 the connection zones 6 and 7 are connected with one another in an interlocked manner, in relation both to displacement in the direction of the central longitudinal axis 5 and also to rotation about that axis.
The connection point 2 consists of the same plastic as the connection zone 6 and is made together with it by an injection molding process during which, at the same time, the plastic of the connection zone 6 is injection molded around the insert 8 . Moreover, the connection point 3 consists of the same plastic as the connection zone 7 and is made together with it by an injection molding process during which, at the same time, the plastic of the connection zone 7 is injection molded around the insert 8 .
Each connection point 2 , 3 has a recess 11 which forms a through-going hole of circular shape. Into each of these recesses 11 is inserted a joint, for example in the form of a ball joint or a rubber mounting, after which the chassis component 1 is fitted into the vehicle by means of the joints. In addition recesses 12 are formed in the connection zones 6 and 7 , which serve to reduce the weight.
FIG. 4 shows a schematic plan view of the chassis component 1 with joints 13 and 14 inserted, these in this case being in the form of rubber mountings. The inner parts 15 and 16 of the joints 13 and 14 are fixed onto schematically indicated vehicle components 17 and 18 , such that the vehicle component 17 is for example a wheel carrier and the vehicle component 18 is for example part of the vehicle body or an auxiliary frame.
Schematically, FIG. 4 also shows a detection device 25 , which comprises an electrical conductor 26 that extends along the insert 8 in the form of a closed conductor loop and is fixed within the plastic material of the connection zones. If the insert 8 is deformed, the electrical conductor 26 breaks and this can be detected by the detection device 25 .
FIG. 5 shows schematically a plan view of a chassis component 1 according to a second embodiment of the invention; in the figure, features identical or similar to those of the first embodiment are provided with the same indexes as in the first embodiment. The difference from the first embodiment is that the chassis component 1 is in the form of a three-point control arm and has three connection points 2 , 3 and 19 , which are located at the corners of a triangle and which form in each case a joint holder. The connection points 2 , 3 and 19 are connected rigidly to one another by means of a structural component 4 which has two limbs 20 and 21 that extend obliquely relative to one another and is divided into five zones. A connection zone 6 of the structural component 4 is formed integrally with the connection point 2 , which latter forms a free end of the connection zone 6 . Furthermore, a connection zone 7 of the structural component 4 is formed integrally with the connection point 3 , which forms a free end of the connection zone 7 . In addition a connection zone 22 of the structural component 4 is formed integrally with the connection point 19 , which forms a free end of the connection zone 22 . Thus, the connection zones 6 , 7 and 22 form end areas of the structural component 4 . A distance away from the connection points 2 and 3 , the connection zones 6 and 7 are connected rigidly to one another by means of an insert 8 , which defines an intermediate section 9 of the structural component 4 . Furthermore, a distance away from the connection points 3 and 19 , the connection zones 7 and 22 are connected rigidly to one another by means of an insert 23 , which defines an intermediate section 24 of the structural component 4 .
The limb 20 comprises the connection zones 6 and 7 and also the intermediate section 9 , while the limb 21 comprises the connection zones 7 and 22 and also the intermediate section 24 . Since the inserts 8 and 23 , as also the limbs 20 and 21 , extend obliquely relative to one another, the intermediate sections 9 and 24 are orientated for loads acting from different directions.
The insert 8 is formed by one of the profiles shown in FIGS. 6 a -6 i and is provided at its ends in each case with through-going holes 10 . Moreover, the insert 8 consists of a ductile material, in particular a metal. The connection zones 6 and 7 consist of plastic and the ends of the insert 8 have the plastic material of the connection zones 6 and 7 injection molded around them, so that the plastic extends through the through-going holes 10 . Thus, the connection zones 6 and 7 are connected to one another in an interlocked manner by means of the inert 8 .
The insert 23 is also formed by one of the profiles shown in FIGS. 6 a -6 i and is provided at its ends in each case with through-going holes 10 . Moreover, the insert 23 consists of a ductile material, in particular a metal. The connection zones 7 and 22 consist of plastic and the ends of the insert 23 have the plastic material of the connection zones 7 and 22 injection molded around them, so that the plastic extends through the through-going holes 10 . Thus, the connection zones 7 and 22 are connected to one another in an interlocked manner by means of the inert 23 .
The connection point 2 consists of the same plastic as the connection zone 6 and is made together with it by an injection molding process during which, at the same time, the plastic of the connection zone 6 is injection molded around the insert 8 . Moreover, the connection point 3 consists of the same plastic as the connection zone 7 and is made together with it by an injection molding process during which, at the same time, the plastic of the connection zone 7 is injection molded around the inserts 8 and 23 . In addition, the connection point 19 consists of the same plastic as the connection zone 22 and is made together with it by an injection molding process during which, at the same time, the plastic of the connection zone 22 is injection molded around the insert 23 .
Each connection point 2 , 3 , 19 has a recess 11 in the form of a through-going hole of circular shape. Into each of these recesses 11 is inserted a joint, for example in the form of a ball joint or a rubber mounting, after which the chassis component 1 is fitted into the vehicle by means of the joints. In the second embodiment the recess 11 of the connection point 3 extends transversely to the recess 11 of the connection points 2 and 19 .
FIGS. 6 a -6 i shows sections through the insert 8 taken along the section line 6 - 6 in FIG. 5 , wherein nine different variants are shown for the ductile insert 8 . Any of these variants can be chosen for the inserts 8 and 23 . It is also possible to choose different variants for the inserts 8 and 23 .
Variant of FIG. 6 a shows a two-part design of the insert 8 , whose parts are in each case connected by electric conductors 26 and 27 to a detection device 25 . If the insert 8 is deformed the distance between the two parts changes, which results in a change of the electrical capacitance of the condenser formed by the two parts which is indicated schematically by a symbolic condenser symbol C. The capacitance change can be measured by the detection device 25 , which can accordingly detect deformation of the insert 8 .
Variant of FIG. 6 g also shows a two-part design of the insert 8 , whose parts are each connected by respective electric conductors 26 and 27 to a detection device 25 . If the insert 8 is deformed, the distance between the two parts changes so that they can come into electrical contact with one another; this can be measured by the detection device 25 , which can therefore detect deformation of the insert 8 .
Obviously, it is also possible to monitor a deformation of the insert 23 by means of the detection device or another detection device.
FIG. 7 shows a schematic plan view of a chassis component 1 according to the third embodiment of the invention; in the figure, features identical or similar to those of the previous embodiments are provided with the same indexes as for the previous embodiments. The third embodiment is a three-point control arm and is designed similarly to the second embodiment. However, the difference from the second embodiment is that the structural component 4 is U-shaped, so that the inserts 8 and 23 extend parallel to one another. Moreover, in the third embodiment the recesses 11 of the connection points 3 and 19 extend transversely to the recess 11 of the connection point 2 . For the further description of the third embodiment reference should be made to the description of the second embodiment.
INDEXES
1 Chassis component
2 Connection point
3 Connection point
4 Structural component
5 Longitudinal central axis of the structural component
6 Connection zone of the structural component
7 Connection zone of the structural component
8 Ductile insert
9 Intermediate section of the structural component
10 Through-going hole in the insert
11 Recess in the connection point
12 Recess in the connection zone
13 Joint
14 Joint
15 Inner part of joint
16 Inner part of joint
17 Vehicle component
18 Vehicle component
19 Connection point
20 Limb of the structural component
21 Limb of the structural component
22 Connection zone of the structural component
23 Ductile insert
24 Intermediate section of the structural component
25 Detection device
26 Electrical lead
27 Electrical lead | A vehicle component with at least two connection points, a structural component that extends between the connection points and rigidly connects them with one another. The structural component comprises at least one insert made of a ductile material and at least two connection zones that support or form the two connection points, at least one of the zones comprises plastic. The structural component comprises at least one intermediate section that connects the two connection zones rigidly to one another and comprises the insert or is formed by the insert, this section is more ductile than at least one of the two connection zones and, in relation to a mechanical overload of the structural component, forms a locally delimited weak-point or region. | 5 |
RELATED APPLICATIONS
[0001] The present application is related to Republic of Croatia Patent Application Number P20040907A, filed on Jul. 28, 2004, and makes claim to priority there pursuant to 35 U.S.C. § 119.
TECHNICAL FIELD OF THE INVENTION
[0002] The present invention broadly relates to the art of automated sports contains. More specifically it relates to a novel air pump/pressure switch module unit that has utility in an automated sports contain environment as well as other environments such as hand spayers and misters.
BACKGROUND OF THE INVENTION
[0003] Most energy consuming activities such a various sports activities often require the expendature of physical activity for extended periods of time. Exemplary, but not exclusive of such activities are: running, bicycling, wind surfing, rock climbing, car racing, motorcycling, in-line skating, auto racing and jogging. During such strenuous activity the human body naturally loses bodily fluids through perspiration. Depending on the physical conditions, intensity of activity and climate conditions, the human body can lose as much as one (1) liter of bodily fluids per hour. If these fluids are not replenished during these times of activity, at best a marked decline in the performance of the activity, or at worst more serious consequences, e.g., heat stroke, can result. Specifically, in the case of sports activities, an athlete's competitive edge will be lost. Thus, the efficient and effective replenishment of lost fluid during such activities has presented a problems to the practitioners of the prior art. Moreover, problems exist among handicap individuals who do not have manual dexterity sufficient to quench themselves.
[0004] The prior art has attempted to solve these problems in various ways, as exemplified by the following patents:
[0005] U.S. Pat. No. 5,607,087, to Wery, et al., issued Mar. 4, 1997, discloses A pressurized fluid dispensing device for storing and dispensing pressurized fluid, such as water, to individuals during the performance of their particular activity. The pressurized fluid dispensing device may be mounted on a bicycle frame, wheel chair frame, car dash, or may even be worn on the body by mounting the device to what is commonly known as a water bottle or fanny pack located on the waist of the individual. The device includes a fluid vessel, support cage (optional), male coupling member, a vessel cap with a female coupling member with a check valve incorporated within, tubing, actuateable valve, and a pressure adapter with a check valve. The fluid vessel is pressurized by slidingly inserting the pressure adapter and charging the system with a common air pressurizing system. The vessel now acts as a pre-charged cassette and may be sealingly engaged with the male coupling member which activates the one way valve and allows the contents to flow through the tubing to the actuate-able valve. The valve is actuated by deforming the hollow member by activities such as biting with the mouth or pinching with the fingers.
[0006] U.S. Pat. No. 5,326,124, to Allemang, issued Jul. 5, 1994, discloses an improved water delivery apparatus which may be adapted to be mounted for use on a bicycle in which water may be delivered to be sprayingly discharged through the sprayer or to a mouthpiece which may be placed in a bicycle rider's mouth to permit water to be discharged directly therein. This apparatus operates with an existing standard water bottle for a bicycle and alleviates the possibility of having a stream of water misdirected, distracting the rider, nor will a rider be caught off-guard receiving a stream of water in the face when a spray was anticipated
[0007] U.S. Pat. No. 5,645,404, to Zelenak, issued Jul. 8, 1997, discloses a personal fluid delivery device that includes an electronic pump system and may also include a fluid reservoir system. The fluid reservoir system includes a fluid reservoir and a delivery tube disposed in communication therewith. The electronic pump system includes a pump operable for delivering fluid from the fluid reservoir, an electrical power supply for supplying power to the pump, a dispensing tube operable for providing a passageway for dispensing fluid from the fluid reservoir and an actuating device operable for selectively actuating the pump
[0008] U.S. Pat. No. 5,215,231, to Paczonay, issued Jun. 1, 1993, discloses and apparatus for dispensing liquid into the mouth of a bicyclist. The apparatus includes a container with a flexible wall, an adjustable holder for holding the container on a bicycle, a liquid delivery tube extending from the container, and at least one compressor arm that can be actuated by the bicyclist for compressing the container wall and forcing liquid into the liquid delivery tube. Valves connected to the liquid delivery tube prevent back flow of liquid in the direction of the container.
[0009] U.S. Pat. No. 5,062,591, to Runkel, issued Nov. 5, 1991, discloses a drinking system for a rider of a bicycle characterized by inflatable upper portion with suitable conduit and valves for conveying the potable beverage stored in the inflatable upper portion to the drinker on the bicycle so the bicycle rider can drink a potable beverage without having to stop the bicycle.
[0010] U.S. Pat. No. 4,815,635, to Porter, issued Mar. 28, 1989, discloses a water supply apparatus that can be utilized in conjunction with a bicycle to enable a rider to receive either a spray of cooling water or a stream for drinking purposes. A diaphragm-type pump supplies the water. Plural reservoirs enable a plurality of liquids to be transported and utilized, such as water for cooling the rider and a sucrose solution for energy.
[0011] U.S. Pat. No. 4,911,339, to Cushing, issued Mar. 27, 1990, discloses a liquid dispensing apparatus, suitable for mounting on a bicycle safely that provides the rider of the bicycle a way to refresh himself without having to stop and dismount the bicycle. In a preferred embodiment, the apparatus generally includes a cylindrical housing containing a supply of liquid. The liquid is dispensed through an unrestricted length of flexible tubing, leading from the housing to a nozzle which is disposed on the handle bars of the bicycle. A pleated bellows is disposed at the bottom of the housing and forms a chamber for holding compressed air. Each inward stroke of the bellows forces air into the chamber so as to hold the contents under pressure. Adjacent the nozzle, and integrally connected thereto is a hand operated valve which, in its normal state is closed. Depressing the valve forces the liquid out of the container, through the tubing and nozzle, to the rider.
[0012] U.S. Pat. No. 6,722,679, to Englert, issued Apr. 20, 2004, discloses a liquid dispensing apparatus, suitable for mounting on a bicycle safely provides the rider of the bicycle a way to refresh himself without having to stop and dismount the bicycle. In a preferred embodiment, the apparatus generally includes a cylindrical housing containing a supply of liquid. The liquid is dispensed through an unrestricted length of flexible tubing, leading from the housing to a nozzle which is disposed on the handle bars of the bicycle. A pleated bellows is disposed at the bottom of the housing and forms a chamber for holding compressed air. Each inward stroke of the bellows forces air into the chamber so as to hold the contents under pressure. Adjacent the nozzle, and integrally connected thereto is a hand operated valve which, in its normal state is closed. Depressing the valve forces the liquid out of the container, through the tubing and nozzle, to the rider.
[0013] U.S. Pat. No. 5,735,440, to Regalbuto, issued Apr. 7, 1998, discloses a fluid dispensing apparatus is mounted to and supported by any of numerous sizes and styles of bicycles. The fluid dispensing apparatus has a means for storing water, a means for pressurizing stored water, a means for controlling the release of pressurized water in the form of a plurality of high velocity water jets, a means for independently aiming said water jets, a means for conducting fluid between components, and a means for mounting components to the frame of a bicycle. One embodiment of the invention incorporates one or a plurality of serially connected pressurized water reservoir assemblies, a dual piston-in-cylinder water pump assembly, a manually operated water pump lever assembly, an assembly of multiple independent, manually-activated triggers, and multiple independently aimable nozzles. The reservoir, pump, and trigger assemblies are mounted to and supported by frame members of the bicycle. The nozzles are mounted to the trigger assembly, a point on the frame, or to the helmet or body parts of the rider.
[0014] U.S. Pat. No. 5,158,218, to Wery, issued Oct. 27, 1992, discloses a pressurized fluid dispensing device for storing and dispensing pressurized fluid, such as water, to athletes during the performance of their particular activity, particularly endurance events such as a bicycle tour, biathlon, triathlon and the like. The pressurized fluid dispensing device may be mounted to the frame of a bicycle between the vertical and diagonal supports above the center bracket or crank assembly to provide as low as possible center of gravity. The device includes a support cage, fluid vessel, tubing and an actuateable valve. The fluid vessel may be pressurized and slidingly inserted into the support cage to supply fluid through the tubing to the valve. A check valve extends from the bottom of the vessel which is sealingly engageable with a recess formed in the bottom of the support cage through which the fluid may flow. The actuateable valve is actuated to dispense fluid by being bitten. In addition, the actuateable valve may be actuated by hand to spray fluid therefrom to refresh the rider.
[0015] U.S. Pat. No. 5,301,860, to Paczonay, issued Apr. 12, 1994, discloses an apparatus for dispensing liquid into the mouth of a bicyclist, the apparatus including a container with a flexible wall, an adjustable holder for holding the container on a bicycle, a liquid delivery tube extending from the container, and at least one compressor arm actuatable by the bicyclist for compressing the container wall and forcing liquid into the liquid delivery tube. Valves connected to the liquid delivery tube prevent back flow of liquid in the direction of the container.
[0016] U.S. Pat. No. 5,201,442, to Bakalian, issued Apr. 13, 1993, discloses a remotely actuated apparatus is provided for delivering a liquid to a desired location, particularly for use with a bicycle. The invention includes a reservoir, a pump adapted to receive liquid from the reservoir regardless of the orientation of the reservoir, a delivery tube for delivering liquid from the pump to a desired location, and a remote actuator for remotely actuating the pump. Also included in a preferred embodiment is a manifold which receives liquid from the pump. The manifold has a plurality of outlet ports to facilitate attachment of the delivery tube thereto regardless of the orientation of the apparatus. The actuator is disposed remotely from the reservoir and sends a signal which is received by a receiver means which actuates the pump to dispense refreshment liquid through the manifold to a delivery tube and then to a dispensing tube which is in close proximity to the mouth of the bicycle rider.
[0017] Typically, the sports bottles of the prior art include a short straw on the top lid and and a plug on the other end. In order to accomplish hydration, one has to reach out for the bottle, press with their teeth on the plug on the other side of the short straw, tilt their head into an unnatural backward movement, drink by active sucking movements, place the plug back and then return the bottle to the initial placement. In order to complete this complex action, the athlete loses their concentration and disrupts their pattern of breathing, and the action is time consuming.
[0018] The majority of the prior art sports bottle designs dispense liquids by suction produced by the mouth of the user. Typically these designs are directed toward polymeric liquid containers that can be placed in a backpack. A straw extends from the backpack, to near the user's mouth. This permits comfort of drinking and may be a suitable solution for some users of the bottle such as joggers and walkers, and the like.
[0019] However, from a practical prospective, these designs embody certain drawbacks for the competative athlete. An athelete is in effect, a highly complex system. A highly complex system is subject to drawbacks. These drawbacks can best be illustrated by reference to the “butterfly effect.” Simply stated, when a butterfly flaps its wings in China, it can ultimately effect the weather in New York. The analogy to competitive sports is manifest: the slightest distraction from the athelete's focus, or althelete's slightest waste of energy, can result in a profound effect in performance. As applied to the art of sports bottles, with the typical sports bottle on the market today, the athlete is required to waste valuable energy to produce sufficient oral suction to withdraw the liquid from it. This twofold problem, e.g., (1) the waste of energy; and, (2) distraction from focus on the objective (e.g., winning a competition), although arguably slight, could be sufficient to disrupt the athelete's patterns of breathing; thereby profoundly impairing the athelete's competative edge (e.g., causing the athelte to lose the competition).
[0020] Various of the prior art patents (e.g., those cited above) solves the energy waste aspect of the problem through the employment of liquid pumps to force feed the liquid from the sports bottle. However, these inventions have had only met with limited success.
[0021] Of those prior art patents cited above, only two (2) employ an electrical switch in a sports bottle environment. These are Zelenak '404 and Bakalian '442.
[0022] The mercury switch of Zelenak '404 is preferably operable to selectively actuate the pump based on its orientation. When the Zelenak mercury switch is positioned near the dispensing end of a dispensing tube, this arrangement provides the advantage of making the pump of Zelenak, selectively actuatable based on the manipulation of the dispensing end of the dispensing tube. This arrangement is preferred because it reduces the need for manual dexterity in operating the pump. When the dispensing end of the dispensing tube is oriented in a downward vertical direction, the mercury switch does not permit the electrical circuit with the pump to be completed, so that the pump does not run. Alternatively, when the dispensing end of the dispensing tube is raised in an upwardly vertical direction, the mercury switch permits the electrical connection with the pump to be completed, thereby actuating the pump and causing the pump to remain in operation until the dispensing tube is returned to a downward vertical position, thereby discontinuing the electrical connection with the pump.
[0023] Bakalian '442, on the other hand, teaches a pump drive actuating means for actuating the pump drive that typically includes a solenoid switch connected to a radio receiver. Also included in the actuating means is an antenna. A relay is connected between the radio receiver and to a battery, to enable a signal from the remote actuating means to be received by the pump actuator antenna and then to be relayed through the pump drive actuating means to cause the pump drive to drive the pump for a predetermined interval to dispense a specific quantity of liquid into the outer concentric manifold and then into the delivery tube.
[0024] Although the Zelenak '404 and Bakalian '442 inventions arguably have some limited success in addressing the waste aspect of the problem, they have little or no impact on the distraction aspect of the problem which is crucial to maintaining a competitive edge in highly competitive sports activities.
[0025] In contrast to Zelenak '404 and Bakalian '442, the present invention employs an automated air pump unit having application in a sports bottle environment for providing a substantially constant, predictable on-demand flow of liquid by merely biting down on the dispensing tube of the present invention. As will be described in further detail below, with respect to two (2) of its embodiments, the automated air pump unit is designed to be detachably, attachable in a sports bottle environment. As will be described in further detail below, in a third embodiment, the automated air pump unit is permanently integrated into the sports bottle environment. By providing these alternate embodiments, the present invention solves the problems of energy waste and distraction that have been recognized by the prior art, in any of the attachably, detachable or integrated embodiments reference above.
[0026] Thus, it is an object of the invention to provide an new and improved air pump and pressure switch combination module unit that that has particular utility in a sports bottle environment.
[0027] It is an object of the invention to provide an new and improved air pump and pressure switch combination module unit that that has broader application in environments other than sports bottle environments, such as a spray bottle or mister environments.
[0028] It is a further object of the invention to provide a new and improved sports bottle that employs a new and improved means for providing predictable, substantially constant on-demand flow of thirst quenching liquid to a user.
SUMMARY OF THE INVENTION
[0029] The primary object of the present invention is to provide ready, predictable and substantially constant, on-demand, thirst quenching of participants in physical activities such as sports, wherein the human body is prone to rapid dehydration. A further object of this invention is to provide a device that includes structure enabling it to be mounted a diversity of environments: including but not limited to, exercise equipment, e.g., stairmasters, tread mills, and the like; belt systems adapted, e.g., to be worn around the waiste of the user; and car dash-board mounts, and the like. These expedients are designed to permit hands-free use of the device in these inviroments. The device comprises a container, such as, a bottle or a polymeric bag, either of which is designed with a (typically female) plug connector for enabling detachable, attachment of an elongated flexible despensing tube extending from the bottom of the container. The free end of the dispensing tube is preferably provided with a valve that may, preferably, be acutated by the teeth and/or mouth of the user. As a further refinement, a clip may be mounted on the valve for enabling it to be clipped onto the clothing of the user at a site excessible to the user's mouth (e.g., the lepal or breast pocket). The clip may be similar in design to that of the clip of a pen.
[0030] The invention comprises three (3) basic embodiments. The first embodiment is an article of manufacture in the form of an automated air pump/pressure switch module unit for use with a sports bottle. Sports bottles are typically used dispensing a liquid to an individual who is engaged in a physical activity whereby bodily fluids are lost at an accelerated rate though the process of perspiration. The typical sports bottle (or, polymer sports bag, as the case may be) embodies a substantially fluid tight container having an interior for containing both the liquid and an airspace above the liquid. The bottle typically includes a conduit having a valve mounted in it at one end, and structure for fixing the other end. The article of manufacture is a compact module unit that includes a support that has a twofold function. The first function of the support is to securingly integrate the other individual elements of the article. The other function of the support is enable the other elements of article to be sealingly, detachably attached to the bottle as a single unit. The other elements of the module unit include: an air pump having an air intake and an air discharge; a holder for securing a power source for driving the air pump (typically batteries); a pressure switch operatively connected to the air pump that preferably includes high and low pressure sensors; and, structure for enabling the air discharge of the air pump to be detachably attached to the container sufficient to enable the module unit to pump air into the the interior of the container. Optionally, the module unit may include an on/off switch designed to override the automated pressure switch.
[0031] The second embodiment of the invention, differs from the first embodiment only in respect to the dispensing tube. In the case of the second embodiment the dispensing is integrated into the unit. As noted above, In the case of the first embodiment, it is not integrated into the unit.
[0032] The third embodiment of the invention comprises the all of the elements of the novel automated unit combined with all of the elements of the typical sports bottle system.
[0033] The units of the first and second embodiments may be marketed separately from the device; with or without batteries. Alternatively, as in the case of the third embodiment of the invention, the unit can be marketed in combination the device; with or without batteries.
BRIEF DESCRIPTION OF THE DRAWINGS
[0034] FIG. 1 shows a isometric view of the most preferred embodiment of the invention.
[0035] FIG. 2 shows a cross-sectional elevation view of an alternate preferred embodiment of the invention having double liquid dispensing conduits.
[0036] FIG. 3 shows a cross-sectional elevation view of yet another alternate preferred embodiment of the invention which includes a reserve bottle for increasing liquid volume.
[0037] FIG. 4 shows a longitudinal cross-sectional elevation view of the preferred embodiment of the invention depicted in FIG. 1 .
[0038] FIG. 4A shows the preferred embodiment of FIG. 1 mounted on a bicycle wherein the dispensing conduit is disposed in a non-drinking orientation.
[0039] FIG. 4B shows the first preferred embodiment of FIG. 1 mounted on a bicycle wherein the dispensing conduit is disposed in a drinking orientation.
[0040] FIG. 5 shows a phantom prospective view of an alternate preferred embodiment of the invention that includes a polymeric bag-type container.
[0041] FIG. 5A shows a side cross-sectional elevation view of FIG. 5 , depicting the polymeric bag-type container in a filled condition.
[0042] FIG. 5B shows a side cross-sectional elevation view of FIG. 5 , depicting the polymeric bag-type container in a partially filled condition.
[0043] FIG. 6 shows a longitudinal, cross-sectional, fragmentary, detail view of the hands-free valve of the invention, situate at the free end of the flexible dispensing conduit.
[0044] FIG. 7 shows a cross-sectional elevation view of an alternative of FIG. 1 that includes a bottom situated, attachably, detachable air pump/pressure switch module unit.
[0045] FIG. 7A shows a fragmented cross-sectional elevation view of the alternative of FIG. 1 wherein the bottom portion in its attached condition.
[0046] FIG. 7B shows a fragmented cross-sectional elevation view of the alternative of the most preferred embodiment of FIG. 1 wherein the bottom portion is in its detached condition.
[0047] FIG. 8A shows a cross-sectional elevation view of an alternate preferred embodiment of the invention depicting a polymeric bag-type container having the detachable novel air pump assembly/pressure switch module unit in its detached condition.
[0048] FIG. 8B shows a cross-sectional elevation view of an alternate preferred embodiment of the invention depicting a polymeric bag-type container having the novel detachable air pump assembly/pressure switch module unit assembly in its attached condition.
[0049] FIG. 9 shows a cross-sectional elevation view of the invention depicting yet another preferred embodiment with integrated dispensing tube 3 in its attached condition.
[0050] FIG. 10 shows a cross-sectional elevation view of the invention depicting the second preferred embodiment with integrated dispensing tube 3 in its detached condition.
[0051] FIG. 11 shows a preferred embodiment of the invention secured to a bicycle.
[0052] FIG. 11A shows a plan view of the means securing the preferred embodiment of FIG. 11 .
DETAILED DESCRIPTION OF THE INVENTION
[0053] The individual automated liquid dispensing system of the present invention includes a polymeric bottle or a polymeric bag-type container, sealingly secured; either permenantly; or, attachably, detachable; to the novel automated air pump/pressure switch module unit structure.
[0054] FIG. 1 depicts the basic embodiment of the individual automated liquid dispensing system that includes a bottle 1 , having a plug 2 , with a flexible conduit 3 , and a valve 4 . A lower part of the bottle 1 includes the novel powered, pressure switch/air pump assembly module unit (not specifically shown). Plugs 2 may be removed to enable bottle 1 to be re-filled with any suitable liquid, such as water or any sports drink containing electrolytes, such as gatorade™.
[0055] FIG. 2 depicts the individual automated liquid dispensing system bottle 1 used with top plug with a double straw 23 so the same bottle system can be used by two individuals. As in the case in all embodiments of the invention, pressure developed by air pump/pressure switch module unit assembly at the bottom portion bottle 1 forces the liquid contained within 13 through the flexible conduit 24 that branches into two straws ( 25 , 26 ). Each branch of the flexible conduit has a valve ( 27 , 28 ). This embodiment of the invention has a preferred application for long automobile or double motorcycling trips wherein a plurality of users is contemplated.
[0056] Referring now to FIG. 3 ; the figure depicts a two bottle dispensing system. Both bottles ( 18 , 19 ) as a sealed system unit. The bottle 18 of the system contains liquid within its interior 21 . That liquid is caused to flow through the flexible conduit 17 into the reserve bottle 19 thereby doubling the liquid capacity of the system. The common pressure of the system operates to force the liquid 22 from the reserve bottle 19 through the flexible conduit 20 . When valve 4 (see, e.g., FIG. 1 ) is caused to be opened, the liquid will be caused to flow through flexible conduit 20 . The automated air pump/pressure switch system, as will described in greater detail, infra, functions to maintain sufficient pressure within the system so as to force liquid from bottle 18 and 19 through conduit 20 when the valve is activated.
[0057] When bottle 18 is emptied, the system will continue pumping the air into a reserve bottle 19 through the flexible conduit 17 until the reservoir of the reserve bottle 17 is emptied as well. The air pump will continue to operate until the maximum set pressure of the high pressure sensor is reached. When the maximum pressure value is reached, air pump 8 will be deactivated by pressure switch 10 as more specifically depicted in FIG. 4 , infra.
[0058] FIG. 4 depicts bottle 1 , divided into two zones; air/liquid reservoir 6 ; and, the inventive, air pump/pressure switch module unit 7 . The module unit 7 contains: an air pump 8 with an air tube 9 ; a pressure switch 10 that includes a pressure sensors to sense pressure within the interior of the system 6 ; and, batteries 11 . Optionally, pressure switch 10 may include an on/off switch (not shown) for overriding the pressure sensors (this expedient is applicable to all embodiments of the invention). When the on/off switch is toggled to the “on” position, pressure switch 10 will be activated thus will be controlled by the pressure sensors. When pressure switch 10 is toggled to the “off” position, pressure switch 10 will be deactivated, thus inactivating the pressure sensors. Thus in this mode, the air pump 8 will be activated by a low pressure sensor and deactivated by a high pressure sensor embodied in pressure switch.
[0059] As is the case in other of the embodiments of the present invention, top plug 2 secures flexible conduit 3 to the top portion of bottle 1 . Flexible conduit 3 sealingly extends through top plug 2 to about the bottom of the liquid contained within bottle 1 . The other end of flexible conduit 3 includes valve 4 . Valve 4 optionally includes a pen like clip (not shown) for securing that end to, e.g., the clothing, and the like, of the user. Air pump 8 is an integral part of unit 7 and communicates with the liquid volume contained within bottle 1 by air tube 9 . The bottle 1 is filled with liquid indicate as indicated at about 13 . Pressure switch 10 is typically activated during the entire period of liquid demand, e.g., the time period during physical activity. Activation of pressure switch 10 , causes air pump 8 to force air into the bottle reservoir 6 through the air tube 9 . Deactivation of valve 4 causes the pressure to rise within the bottle to the predetermined high pressure switch set point which in turn causes pressure switch 10 to deactivate pump 8 .
[0060] When valve 4 is opened by the mouth and/or teeth of the athlete/user, the liquid will flow through the flexible conduit 3 , forced by the pressure within bottle 1 . The automated air pump/pressure switch unit 7 will maintain sufficient pressure within bottle 1 to accommodate liquid demand in response to the activation of mouth activated valve 4 . Stated otherwise, so long as the valve 4 is activated by the mouth and/or teeth of the athelete/user, the minimum set point pressure will be tend to be maintained within the bottle 1 by unit 7 and air pump 8 will continue to be activated. Conversely, when valve 4 is de-activated, the pressure within the bottle 1 will rise to and/or above the predetermined high pressure set point and the air pump will be deactivated.
[0061] FIGS. 4A and 4B show the dispensing system 1 of FIG. 4 mounted on a bicycle. FIG. 4A shows flexible conduit 28 positioned in the non-drinking position, while FIG. 4B shows flexible conduit 28 positioned in the drinking position.
[0062] Preferrably, conduit 28 is constructed of a substantially rigid, flexible material and designed to enable it to be temporarily deformed. Although any suitable plastic material know to the prior art can be used to construct conduit 28 , the preferred materials of contruction are polyethylene or polypropylene. Preferrably the bending joint of conduit 28 is typically formed in a well-known accordian-type construction which enables the conduit to be readily deformed into to either the drinking/non-drinking configurations.
[0063] FIG. 5 shows an individual automated liquid dispensing system including a plastic, polymeric container 31 .
[0064] FIGS. 5A and 5B show the automated liquid dispensing system installed at the top of plastic, polymeric container 31 . FIG. 5A specifically shows air pump/pressure switch module unit 7 in its sealingly attached mode; while FIG. 5B specifically shows air pump/pressure switch module unit 7 in its detached mode. As described elsewhere herein with respect to the operation of basic system, when valve 4 is closed, the pressure raises until the upper limit pressure sensor de-activates the air pump (it should be noted that this automated system can be over-ridden with an optional on/off switch as described elsewhere herein). This embodiment is contemplated for runners, bicyclists, car racers, and for use during long distance travel. The application of this embodiment also contemplates use by handicapped individuals limited in mobility and hand dexterity.
[0065] FIG. 6 shows the hands-free valve 36 located at the free end of flexible conduit 37 . Hands-free valve 36 is designed to enable forced flow of the liquid stream to the user's mouth merely througth the pressure of the user's teeth and/or lips. The valve includes in a ball member 38 normally sealingly positioned in a seat indicated below about element 39 . The ball is typically constructed of substantially any suitable hard, substantially non-deformable material, e.g., glass, metal, hard plastic, and the like. Of these materials, hard plastic is preferred. On the other hand, the seat and body indicated generally at 36 is constructed of a suitable, comparatively soft, deformable material of construction, such as, surgical rubber, silicone rubber, and the like. Of these materials, surgical rubber is preferred. In its de-activated mode, pressure within the automated dispensing system forces the ball against the seat portion of the valve thus impeding flow of the liquid through the dispensing tube. The valve is activated when the seat portion is deformed through the action of the mouth and/or teeth of the user. This deformation of the seat causes a liquid channel[s] to be formed between the interior of the depensing system and the mouth of the user, whereby pressurized liquid is caused to flow through the dispensing tube into the mouth of the user, until the pressure by the mouth and/or teeth of the user on the valve seat is relaxed.
[0066] FIG. 7 shows the novel air pump/pressure switch unit as a detachably-attachable module unit 41 . In this embodiment the module unit 41 includes in integrated construction: the air pump 8 with air intake (depicted as slots) and air discharge conduit 9 ; and, the pressure switch 10 with pressure sensors. The module unit 41 and bottle 1 are both threaded in such a manner that the module unit 41 can be screwed to the bottle to enable sealed communication; and conversely, unscrewed for removal from the bottle. As in the cases above, operation of this embodiment is essentially the same as describe above with respect to the generic embodiment of the present invention. As previously noted above, automated operation of all embodiments of the present invention can be over-ridden by an on/off switch.
[0067] FIG. 7A shows the embodiment of FIG. 7 , wherein the module unit 41 is screwed to the bottle 1 for sealed communication between the module unit and the bottle in its integrated, attached condition.
[0068] FIG. 7B shows the embodiment of FIG. 7 , wherein the module unit is un-screwed from the bottle 1 in its un-screwed, detached condition.
[0069] FIGS. 8A and 8B shows the module unit concept depicted in FIGS. 7, 7A and 7 B adapted to a bag container 31 . FIG. 8A shows the module unit 41 as it is un-screwed from the bag container 31 in its un-screwed, detached condition.
[0070] FIG. 8B shows the module unit 41 as it is sealingly screwed to the bag container 31 in its attached condition. Operation of this embodiment is essentially the same as describe above with respect to the generic embodiment of the present invention. As previously noted above, automated operation of all embodiments of the present invention can be over-ridden by an on/off switch.
[0071] FIG. 9 show essentially all features of the embodiment[s] of FIGS. 7, 7A and 7 B, save for the following refinements. First, the inventive module unit of the invention (indicated in FIG. 9 as element 44 ) is adapted to the form of a lid that is sealingly snapped to the top of bottle 47 . Secondly, the dispensing conduit 3 has been integrated into the module unit 44 . Otherwise, FIG. 9 shows module unit 44 in its sealingly attached condition.
[0072] FIG. 10 shows the embodiment of FIG. 9 wherein module unit 44 is depicted in its detached mode. As in the cases above, operation of this embodiment is essentially the same as describe above with respect to the generic embodiment of the present invention. Again, as previously noted above, automated operation of all embodiments of the present invention can be over-ridden by an on/off switch.
[0073] FIG. 11 shows the generic embodiment of the present invention 47 as mounted on a cross-member support of a bicycle 52 .
[0074] FIG. 11A shows a plan view of the structure securing the preferred embodiment of FIG. 11 . Specifically depicted are: clamp 45 a and securing bolts 53 . As in the cases above, operation of this embodiment is essentially the same as describe above with respect to the generic embodiment of the present invention. As previously noted above, automated operation of all embodiments of the present invention can be over-ridden by an on/off switch.
DEFINITIONS
[0075] The symbol “™” as used herein refers to a trademark.
[0076] The term “polymeric” as used herein, refers to any suitable material of construction that the bottle or bag of the present invention may be constructed. Any suitable plastic presently know by the prior art is contemplated by the present invention. Particularly preferred are any species of polypropylene or polyelthylene and/or mixtures thereof.
[0077] Although the invention has been described with reference to certain preferred embodiments, it will be appreciated that many variations and modifications may be made within the scope of the broad principles of the invention. Hence, it is intended that the preferred embodiments and all of such variations and modifications be included within the scope and spirit of the invention, as defined by the following claims. | The present invention provides the art of sports bottles with a new and improved air pump, air passage, switch, and optional dispensing tube combination that has particular utility in sports bottle environments as well as other enviroments such as the art of spray bottles, misters, and the like. The present invention further provides a new and improved sports bottle that embodies the new and improved air pump, air passage and switch combination. In operation, the switch activates the pump when the pressure within a liquid reservoir falls below a predetermined pressure thus causing the liquid to flow at a predictable, substantially contant on-demand flow through a conduit operatively connected to the reservoir when a valve disposed in the conduit is actuated by pressure of a user's mouth and/or teeth. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to DE Application No. 10 2015 214 702.9 filed Jul. 31, 2015, the contents of which are hereby incorporated by reference in their entirety.
TECHNICAL FIELD
[0002] The disclosure relates to internal combustion engines in general, and teaches various methods and apparatus for operating engines with an exhaust-gas turbocharger.
BACKGROUND
[0003] Combustion machines having an internal combustion engine may include an exhaust-gas turbocharger. An associated operating mode is so-called scavenging. In this case, an inlet valve and an outlet valve of the combustion machine are actuated such that the opening times partially overlap. As a result, a part of the drawn-in fresh gas passes through the cylinder into the exhaust tract (it is scavenged). Said fresh gas in the exhaust tract increases the mass flow for the operation of the turbocharger.
[0004] It is desirable to specify a method for operating a combustion machine, which method permits reliable operation even during scavenging operation. It is also desirable to specify an apparatus which is designed to carry out the method.
SUMMARY
[0005] In some embodiments, a method for operating a combustion machine ( 100 ) having an internal combustion engine ( 101 ), having a fresh-gas tract ( 102 ) for the supply of fresh gas ( 103 ) to a cylinder ( 104 ), and having an exhaust tract ( 105 ) for the discharge of exhaust gas ( 106 ), may include: determining a value of a state of a catalytic converter ( 114 ) which is arranged in the exhaust tract ( 105 ), determining, as a function of the determined value, a first value for a maximum admissible scavenged-over quantity of fresh gas ( 103 ) into the exhaust tract ( 105 ) during scavenging operation, setting the maximum admissible scavenged-over quantity to a second value which is lower than the first value if a predefined value of a further state of the catalytic converter ( 114 ) has been determined.
[0006] In some embodiments, the determination of the value of the state of the catalytic converter ( 114 ) comprises modeling the value of the state.
[0007] In some embodiments, the determination of the value of the state of the catalytic converter ( 114 ) comprises at least one of the following: determining a value of a temperature gradient of the catalytic converter ( 114 ), determining a value of an absolute temperature of the catalytic converter ( 114 ), determining a value of a quantity of hydrocarbons in the catalytic converter ( 114 ), determining a value of an oxygen storage capacity of the catalytic converter ( 114 ), and determining an operating age of the catalytic converter ( 114 ).
[0008] In some embodiments, the determination of the predefined value of the further state of the catalytic converter ( 114 ) comprises at least one of the following: comparing an actual value of a temperature gradient of the catalytic converter ( 114 ) with a predefined value for the temperature gradient, comparing an actual value of an absolute temperature of the catalytic converter ( 114 ) with a predefined value for the absolute temperature, comparing an actual value of a quantity of hydrocarbons in the catalytic converter ( 114 ) with a predefined value for the quantity of hydrocarbons, comparing an actual value of an oxygen storage capacity of the catalytic converter ( 114 ) with a predefined value for oxygen storage capacity, and comparing an actual value of an operating age of the catalytic converter ( 114 ) with a predefined value for the operating age.
[0009] In some embodiments, an inlet valve ( 107 ) for controlling the supply of the fresh gas ( 103 ) is arranged in the fresh-gas tract ( 102 ), and an outlet valve ( 108 ) for controlling the discharge of the exhaust gas ( 106 ) is arranged in the exhaust tract ( 105 ), comprising: determining an opening time period for the inlet valve ( 107 ), determining an opening time period for the outlet valve ( 108 ), determining an overlap period, in which the two opening time periods at least partially overlap, as a function of the maximum admissible scavenged-over quantity.
[0010] Some embodiments include regulating the scavenged-over quantity as a function of a temperature of the catalytic converter ( 114 ) if the predefined value of the further state of the catalytic converter ( 114 ) has been determined.
[0011] Some embodiments include an apparatus for operating a combustion machine ( 100 ), designed to carry out a method as described above.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] Advantages, features, and refinements will emerge from the following examples, which will be discussed in conjunction with the figures, in which:
[0013] FIG. 1 is a schematic illustration of an embodiment of a combustion machine,
[0014] FIG. 2 shows a flow diagram of an embodiment of a method for operating a combustion machine.
DETAILED DESCRIPTION
[0015] In some embodiments of teachings of the present disclosure, the combustion machine has an internal combustion engine, a fresh-gas tract for the supply of fresh gas to a cylinder, and an exhaust tract for the discharge of exhaust gas. A value of a state of a catalytic converter is determined. The catalytic converter is arranged in the exhaust tract. A first value for a maximum admissible scavenged-over quantity of fresh gas into the exhaust tract during scavenging operation is determined as a function of the determined value. The maximum admissible scavenged-over quantity is set to a second value which is lower than the first value if a predefined value of a further state of the catalytic converter has been determined.
[0016] The quantity of fresh gas that is scavenged from the fresh-gas tract through the cylinder into the exhaust tract during scavenging operation is determined as a function of at least a state of the catalytic converter. It is thus possible to realize a desired high mass flow in the exhaust tract and to simultaneously prevent a malfunction in the catalytic converter. The fresh gas that is scavenged through may result in a lean exhaust-gas mixture in the exhaust tract. This may lead to adverse operating conditions for the catalytic converter.
[0017] For example, a deficiency of hydrocarbons in the exhaust gas may have the effect that NOx (nitrogen oxides) can no longer be reduced as intended. The NOx emissions can thus increase. Through the determination of the value for the maximum admissible scavenged-over quantity as a function of the catalytic converter, fresh gas is conducted to the catalytic converter only in such an amount as the catalytic converter can cope with in order to realize adequate reduction of pollutants such as NOx. Here, it is possible to operate at the upper limit of the load capacity of the catalytic converter and thus permit a high enough mass flow for reliable operation.
[0018] In some embodiments, the value of the state of the catalytic convertor and/or the value of the further state are/is measured by way of one or more sensors. Alternatively or in addition, the value of the state and/or the value of the further state are/is determined by way of a predefined model. Costs can be saved in this way.
[0019] In some embodiments, the determination of the value of the state of the catalytic converter comprises at least one of the following:
determining a value of a temperature gradient of the catalytic converter, determining a value of an absolute temperature of the catalytic converter, determining a value of a quantity of hydrocarbons in the catalytic converter, determining a value of an oxygen storage capacity of the catalytic converter, and determining an operating age of the catalytic converter.
[0025] It is thus possible for the maximum admissible scavenged-over quantity to be determined as a function of the temperature of the catalytic convertor and/or of the hydrocarbon saturation of the catalytic convertor and/or of a degree of aging of the catalytic converter. In this way, adequate pollutant reduction by the catalytic converter is possible. In exemplary embodiments, further values of further states of the catalytic converter are alternatively or additionally determined.
[0026] In some embodiments, the determination of the predefined value of the further state of the catalytic converter comprises at least one of the following:
comparing an actual value of a temperature gradient of the catalytic converter with a predefined value for the temperature gradient, comparing an actual value of an absolute temperature of the catalytic converter with a predefined value for the absolute temperature, comparing an actual value of a quantity of hydrocarbons in the catalytic converter with a predefined value for the quantity of hydrocarbons, comparing an actual value of an oxygen storage capacity of the catalytic converter with a predefined value for oxygen storage capacity, and comparing an actual value of an operating age of the catalytic converter with a predefined value for the operating age.
[0032] The determination of the predefined value of the further state corresponds to a determination of a termination condition for the permission of the scavenged-over quantity up to the first value for the maximum admissible scavenged-over quantity. If at least one of the predefined values of at least one of the further states is determined, there is the risk of too much fresh gas being present in the exhaust tract, such that the catalytic converter can no longer adequately reduce pollutants. Thus, the maximum admissible scavenged-over quantity is set to the lower, second value, and thus the amount of fresh gas in the exhaust tract is reduced. In this way, reliable operation of the catalytic converter is made possible.
[0033] In some embodiments, an inlet valve for controlling the supply of the fresh gas is arranged in the fresh-gas tract, and an outlet valve for controlling the discharge of the exhaust gas is arranged in the exhaust tract. An opening time period for the inlet valve is determined. An opening time period for the outlet valve is determined. An overlap period is determined as a function of the maximum admissible scavenged-over quantity. In the overlap period, the two opening time periods at least partially overlap. During the overlap of the two opening time periods, fresh gas is scavenged through the cylinder into the exhaust tract. For example, the maximum admissible scavenged-over quantity is implemented in a characteristic map-based manner by way of corresponding camshaft setpoint values. The camshaft setpoint values predefine the respective opening time periods for the inlet valve and the outlet valve.
[0034] In some embodiments, the scavenged-over quantity is regulated as a function of a temperature of the catalytic converter if the predefined value of the further state of the catalytic converter has been determined. Thus, reliable operation of the catalytic converter is possible even with the second, lower value of the scavenged-over quantity.
[0035] FIG. 1 shows an embodiment of a combustion machine 100 . The combustion machine 100 comprises an internal combustion engine 101 with at least one cylinder 104 and one inlet valve 107 for regulating the fresh gas 103 flowing into the cylinder 104 . The fresh gas 103 flows through a fresh-gas tract 102 to the cylinder 104 . The fresh gas 103 may be in particular air. After the combustion of the fuel in the cylinder 104 , exhaust gas 106 passes via an exhaust tract 105 to a catalytic converter 114 . The catalytic converter may be in particular designed to reduce nitrogen oxides in the exhaust gas 106 .
[0036] The combustion machine furthermore has a supercharging unit 111 , in particular a turbocharger, also referred to as exhaust-gas turbocharger. The turbocharger 111 has a turbine 112 and a compressor 113 . The turbine 112 , which is driven by the gas flow in the exhaust tract 105 , drives the compressor 113 . In this way, the fresh gas 103 conducted through the compressor 113 is compressed before being conducted into the cylinder 104 . It is thus possible for the engine efficiency to be increased, or, for smaller swept volumes, to be kept the same.
[0037] In particular at the low-load operating point of the internal combustion engine 101 , it has hitherto been the case that the exhaust-gas mass flow at the turbine 112 of the turbocharger 111 is possibly not sufficient to be able to set the demanded charge pressure for the operating point of relatively high engine load. The power of the turbocharger 111 increases only gradually in a manner dependent on the continuously rising exhaust-gas mass flow.
[0038] To increase the mass flow in the exhaust tract 105 , so-called scavenging may be performed. Here, fresh gas 103 is scavenged through the cylinder 104 into the exhaust tract 105 without undergoing a combustion process. Thus, for an identical torque output, the mass flow in the exhaust tract 105 is increased. In this way, it is made possible to realize greater power at the turbine 112 . During the scavenging, fresh gas 103 is scavenged via the cylinder 104 into the exhaust tract 105 during a valve overlap of the inlet valve 107 and of an outlet valve 108 . Said fresh gas 103 increases the mass flow and shifts the operating point of the turbocharger 111 into a desired range.
[0039] Said fresh gas 103 passes to the catalytic converter 114 , and passes through the catalytic converter 114 . This results in a lean exhaust-gas mixture, and the catalytic converter no longer operates in its predefined optimum conversion window.
[0040] If certain boundary conditions or states of the catalytic converter exist during the scavenging operation, it is nevertheless possible for emissions to be adequately reduced, in particular for the nitrogen oxide emissions to be reduced.
[0041] This will be discussed in more detail below on the basis of the flow diagram illustrated in FIG. 2 .
[0042] In particular, the combustion machine 100 has an apparatus 120 ( FIG. 1 ) which is designed to carry out the method. For this purpose, the apparatus 120 is for example connected to the inlet valve 107 and/or to the outlet valve 108 in order to open and/or close these. Furthermore, in exemplary embodiments, the apparatus 120 is coupled to the catalytic converter 114 in order to measure or model at least one value of at least one state of the catalytic converter 114 .
[0043] In a method step 201 , it is checked whether a termination condition for the scavenging-over is present. For this purpose, at least one value of a state of the catalytic converter is determined and compared with a predefined value for the state. For example, an actual value of the temperature gradient of the catalytic converter is compared with a predefined value for the temperature gradient. Alternatively or in addition, an actual value of an absolute temperature of the catalytic converter 114 is compared with a predefined value for the absolute temperature. Alternatively or in addition, an actual value of a quantity of hydrocarbons in the catalytic converter 114 is compared with a predefined value for the quantity of hydrocarbons. Alternatively or in addition, an actual value of an oxygen storage capacity of the catalytic converter 114 is compared with a predefined value for the oxygen capacity. Alternatively or in addition, an actual value of an operating age of the catalytic converter 114 is compared with a predefined value for the operating age.
[0044] The predefined values for the states may be predefined such that reliable operation of the catalytic converter 114 is ensured. The predefined reduction of emissions by the catalytic converter 114 is realized in the presence of the predefined values of the states. It is thus possible for actually present values, for example of the temperature or of the quantity of hydrocarbons in the catalytic converter 114 , to be used for permitting reliable operation.
[0045] If all determined values of the states are lower than the respectively associated predefined values, the method proceeds to step 202 . In step 202 , at least one value of at least one state of the catalytic converter 114 is determined. The state or the states used in step 202 may, in part or entirely, be the same states as those taken into consideration in step 201 . The states in step 201 and in step 202 may also differ entirely. For example, in step 202 , a value of a temperature gradient of the catalytic converter 114 is determined. Alternatively or in addition, a value of an absolute temperature of the catalytic converter 114 is determined. Alternatively or in addition, a value of a quantity of hydrocarbons in the catalytic converter 114 is determined. Alternatively or in addition, a value of an oxygen storage capacity of the catalytic converter 114 is determined. Alternatively or in addition, an operating age of the catalytic converter 114 is determined.
[0046] In step 203 , it is subsequently determined how much fresh gas 103 the catalytic converter 114 can presently cope with, at a maximum, in order to operate reliably and reduce the required quantity of pollutants. For this purpose, the maximum admissible scavenged-over quantity of fresh gas 103 is specified as a function of the value or of the values that have been determined in step 202 . It is thus possible for the mass flow in the exhaust tract 105 during the scavenging operation to be increased as desired. The mass flow is however increased only to such an extent that the catalytic converter 114 continues to operate reliably.
[0047] If it is detected in step 201 that a termination condition is present, that is to say that at least one actual value of the states inspected in step 201 corresponds to or exceeds a predefined value, the maximum admissible scavenged-over quantity is, in method step 204 , set to a second value. The second value is set to be so low that the catalytic converter 114 receives only such a quantity of fresh gas 103 that adequate pollutant emission can be realized.
[0048] By way of these teachings, it is possible to avoid a situation in which the exhaust gas 106 in the exhaust tract 105 has an excessively low fraction of hydrocarbons and nitrogen oxides can no longer be adequately reduced. The maximum admissible scavenged-over quantity is always limited such that nitrogen oxide emissions can be adequately reduced or an increase in nitrogen oxide emissions can be avoided.
[0049] The limit for the admissible scavenged-over quantity (also referred to as scavenged-over mass) is determined from the admissible values of the states of the catalytic converter 114 , for example from the admissible exothermic energy in the catalytic converter 114 . It is thus possible for the maximum admissible scavenged-over quantity to be calculated from the permitted values of the states, in particular from the permitted exothermic energy, in an operating point-dependent manner. For example, the maximum admissible scavenged-over quantity is implemented in a characteristic map-based manner by way of corresponding camshaft setpoint values. For example, the inlet valve and outlet valve are opened such that their opening time periods overlap. It is thus possible for fresh gas 103 to pass through the cylinder 104 into the exhaust tract 105 without undergoing a combustion stroke.
[0050] Owing to the determination of the value of the state of the catalytic converter 114 in the step 202 , it is possible, depending on the state of the catalytic converter, for the scavenged-over quantity to be increased; in particular, said increase is possible for a short time. Said higher scavenged-over quantities may be realized with stoichiometric exhaust gas with a high temperature gradient, or with lean exhaust gas with the risk of deterioration of emissions as a result of a breakthrough through the catalytic converter 114 . The breakthrough is prevented because, in step 201 , monitoring is performed to ensure that no termination condition is infringed. In the case of at least one of the predefined termination conditions being satisfied, the maximum admissible scavenged-over quantity is reduced, and is subsequently regulated for example by way of the temperature in the catalytic converter 114 .
[0051] In some embodiments, the values of the maximum admissible scavenged-over quantity are specified as direct setpoint values. In further embodiments, the values of the maximum admissible scavenged-over quantity are specified as limitations and represent the upper limit of a range. A mixture is also possible, such that the values are, in part, specified as direct setpoint values and are, in part, specified as limitations.
[0052] In some embodiments, the values of the states of the catalytic converter, for example the temperature in the catalytic converter 114 , are measured by way of sensors. In further embodiments, the values are modeled. A mixture is also possible, such that the values are, in part, measured by way of sensors and are, in part, modeled.
[0053] By way of these teachings, it is possible for the scavenged-over quantity to be optimized in a manner dependent on a desired mass flow and desired operation of the catalytic converter. The scavenged-over quantity is actively regulated.
LIST OF REFERENCE DESIGNATIONS
[0000]
100 Combustion machine
101 Internal combustion engine
102 Fresh-gas tract
103 Fresh gas
104 Cylinder
105 Exhaust tract
106 Exhaust gas
107 Inlet valve
108 Outlet valve
109 Catalytic converter
111 Supercharging unit
112 Turbine
113 Compressor
114 Catalytic converter
120 Apparatus
201 - 204 Method steps | The disclosure relates to internal combustion engines in general, and teaches various methods and apparatus for operating engines with an exhaust-gas turbocharger. Some embodiments include a method for operating an internal combustion engine having a fresh-gas tract for the supply of fresh gas to a cylinder, and an exhaust tract for the discharge of exhaust gas. They may include determining a value of a first operating condition of a catalytic converter arranged in the exhaust tract; determining a value of a second operating condition of the catalytic converter; calculating, as a function of the determined value, a first value for a maximum admissible scavenged-over quantity of fresh gas into the exhaust tract during scavenging operation; and setting the maximum admissible scavenged-over quantity to a second value lower than the first value if the value of the second operating condition reaches a predefined value. | 8 |
FIELD OF THE INVENTION
The present invention relates to communication network, especially to wireless MEMO communication network.
BACKGROUND OF THE INVENTION
In IMT-advanced (International Mobile Telecommunications-Advanced), the collaborative MIMO (Multiple-Input-Multiple-Output) solution becomes an efficient method to improve the system coverage and spectral efficiency by using a plurality of eNBs (evolved Node B, hereinafter referred to as eNB) to provides one or more mobile stations (MS) with data service via cooperation among the plurality of eNBs to reduce the ICI (Inter-Cell Interference). To implement the collaborative MIMO transmission, same resource needs to be allocated for a plurality of eNBs performing, collaborative MIMO, that is, resource synchronization.
The so-called collaborative MIMO means that both eNB and MS have a plurality of antennas, at least a plurality of eNBs communicate with one MS, one eNB may communicate with one or more MSs. In collaborative MIMO, the serving eNB of one MS requests the neighboring cell eNB to participate in the collaborative MIMO transmission and indicates the resource allocated for this collaboration MEMO to the neighboring cell eNB requested to participate in the collaborative MIMO. If there is no conflict between the resource allocated for the neighboring cell eNB by the serving eNB and the resource of the neighboring cell eNB, then the collaborative MIMO transmission for this MS may be established. Referring to FIG. 1 , FIG. 1 shows a schematic diagram of topology of traditional cellular cell, taking traditional hexagonal cell model as an example for illustration. Each MS has only one serving eNB, the serving eNB of MS is determined during the initial access of MS, MS may handover from original source serving eNB to a new object eNB with the movement of MS. MS 2 a may be taken as a example to illustrate. The serving eNB of MS 2 a is eNB 1 a , since network model is of hexagonal structure, one serving eNB at most has two neighboring cells which may participate in the collaborative MIMO with the serving eNB, the neighboring cell eNB performing the collaborative MIMO with the serving eNB and the serving eNB constitute one collaborative cell cluster. Certainly, in actual network, the serving eNB may have a plurality of neighboring eNBs (hereinafter referred to as neighboring cell eNB). As shown in FIG. 1 , the dot oval frame denotes a collaborative cell cluster performing collaborative MIMO service for MS 2 a , constituted by the serving eNB 1 a , neighboring cell eNBs 1 b and 1 c . In this collaborative cell cluster, the serving eNB 1 a determines resource allocation for this collaborative MIMO transmission.
neighboring cell eNB 1 b shown in FIG. 1 may also be taken as a serving eNB in one collaborative cell cluster and determine MS (not shown in Fig) dominated by it, in this collaborative cell cluster. When each serving eNB allocates resource respectively, it is easy to cause resource conflict and result in CO-MIMO failure.
An existing resource allocation manner for CO-MIMO is shown in FIG. 2 , the shadow with slash lines denotes the resource which may be used for CO-MIMO by eNB 1 a as serving eNB, the blank area denotes the resource which may be used for CO-MIMO by eNB 1 b as serving eNB, the shadow with vertical lines denotes the resource which may be used for CO-MIMO by eNB 1 c as serving eNB, that is, each eNB reserves a part of fixed resource as resource area which may be allocated for collaborative MIMO while it acts as a serving eNB, and the reserved resource areas allocated for each serving eNB to be used for collaborative MIMO with other eNBs are all orthogonal to each other, that is, there is no overlapping part between any two resource areas, so as to guarantee there is no conflict of resources for collaborative MIMO. However, the efficiency of the resource allocation manner, which defining the resource allocation of serving eNB and collaborative eNB in a cell cluster for collaborative MIMO in a predetermined area, is very low. Its disadvantages are as follows:
the reserved resource will be waste, If there is no MS or few MSs desiring collaborative MIMO communication. if there are too many MSs desiring collaborative MIMO in one cell dominated by serving eNB, the reserved resource for this serving eNB will not meet the requirement of collaborative MIMO, so as to cause collaborative MIMO failure. furthermore, that how to define the initial reserved resource area effectively in this predetermined fixed scheme is a problem.
SUMMARY OF THE INVENTION
In order to solve the aforesaid problems in the prior art, the present invention proposes: firstly, the serving eNB determines, in the one or more other eNBs, at least one candidate eNB recommended to cooperate with the serving eNB; then, obtains resource related information of the at least one candidate eNB; and then determines one or more collaborative eNBs from the at least one candidate eNB according to the resource related information, and allocates corresponding communication resources for the serving eNB and the one or more collaborative eNBs.
According to the first aspect of the present invention, there is provided a method, in a serving eNB of wireless communication network based on collaborative Multiple-Input-Multiple-Output, for allocating communication resources for the serving eNB and one or more collaborative eNBs that collaboratively process mobile station service, wherein the method comprises the following steps: determining, in the one or more other eNBs, at least one candidate eNB recommended to cooperate with the serving eNB; obtaining resource related information of the at least one candidate eNB; determining one or more collaborative eNBs from the at least one candidate eNB according to the resource related information, and allocating corresponding communication resources for the serving eNB and the one or more collaborative eNBs.
According to the second aspect of the present invention, there is provided a method, in a candidate eNB of wireless communication network based on collaborative Multiple-Input-Multiple-Output, for assisting a serving eNB in allocating communication resources for the serving eNB and one or more collaborative eNBs that collaboratively process mobile station service, wherein the method comprises the following step: sending resource related information to the serving eNB.
According to the third aspect of the present invention, there is provided a method, in a mobile station of wireless communication network based on collaborative Multiple-Input-Multiple-Output, for assisting a serving eNB in allocating communication resources for the serving eNB and one or more collaborative eNBs that collaboratively process mobile station service, wherein the method comprises the following steps: measuring signal quality related information between the mobile station and the serving eNB, and between the mobile station and one or more other eNBs; determining at least one candidate eNB recommended to cooperate with the serving eNB, according to the signal quality related information; generating candidate eNB indication information for indicating the at least one candidate eNB according to the at least one candidate eNB, and sending the candidate eNB indication information to the serving base station.
According to the fourth aspect of the present invention, there is provided a first collaborative device, in a serving eNB of wireless communication network based on collaborative Multiple-Input-Multiple-Output, for allocating communication resources for the serving eNB and one or more collaborative eNBs that collaboratively process mobile station service, wherein the device comprises: a means for determining candidate eNB, configured to determine, in the one or more other eNBs, at least one candidate eNB recommended to cooperate with the serving eNB; a means for obtaining resource information, configured to obtain resource related information of the at least one candidate eNB; a means for processing, configured to determine the one or more collaborative eNBs from the at least one candidate eNB according to the resource related information, and to allocate corresponding communication resources for the serving eNB and the one or more collaborative eNBs.
According to the fifth aspect of the present invention, there is provided a second collaborative device, in candidate eNB of wireless communication network based on collaborative Multiple-Input-Multiple-Output, for assisting a serving eNB in allocating communication resources for the serving eNB and one or more collaborative eNBs that collaboratively process mobile station service, wherein the device comprises: a means for sending resource information, configured to send resource related information to the serving eNB.
According to the sixth aspect of the present invention, there is provided An assisting device, in a mobile station of wireless communication network based on collaborative Multiple-Input-Multiple-Output, for assisting a serving eNB in allocating communication resources for the serving eNB and one or more collaborative eNBs that collaboratively process mobile station service, wherein the device comprises: a means for measurement, configured to measure signal quality related information between the mobile station and the serving eNB, and between the mobile station and one or more other eNBs; a means for recommendation, configured to determine at least one candidate eNB recommended to cooperate with the serving eNB, according to the signal quality related information; a means for sending, configured to generate candidate eNB indication information for indicating the at least one candidate eNB according to the at least one candidate eNB, and send the candidate eNB indication information to the serving base station.
The solution according to the present does not need to reserve special resource for collaborative MIMO, reduces waste of resource, and meets the demand for resource for implementing collaborative MIMO by different serving eNBs flexibly, and increases the success rate of implementing collaborative MIMO.
BRIEF DESCRIPTION OF THE DRAWINGS
By reading the detailed description of the non-limiting embodiments with reference to the following drawings, other features, objects and advantages of the present invention will become apparent.
FIG. 1 shows a schematic diagram of topology of traditional cellular cell;
FIG. 2 shows an existing resource allocation manner;
FIG. 3 shows a flowchart of system method according to a detailed embodiment of the present invention;
FIG. 4 shows a flowchart of method of the step S 12 to the step S 15 according to another detailed embodiment of the present invention;
FIG. 5A to FIG. 5C respectively shows three different scenarios of common available resource between serving eNB and candidate eNB;
FIG. 6 shows a block diagram a detailed embodiment present invention.
In drawings, same or similar reference signs refer to the same or similar device (module) or step.
DETAILED DESCRIPTION OF EMBODIMENTS
Referring to FIG. 1 , the network topology of the present invention is described as follows. MS 2 a is taken as example for illustration. eNB 1 a is the serving eNB of MS 2 a , furthermore, MS 2 a may also receive signals from other neighboring eNBs, that is, neighboring cell eNBs of eNB 1 a , including eNB 1 b and eNB 1 c . In LTE-Advanced system. eNB 1 a interconnects with eNB 1 b and eNB 1 c via X2 interfaces.
Hereinafter, referring to FIG. 3 and in combination with FIG. 1 , flowchart of system method of the present invention is described as follows. FIG. 3 shows a flowchart of system method according to a detailed embodiment of the present invention.
In step S 10 , the MS 2 a measures signal quality related information between the MS 2 a and the serving eNB 1 a , and between the MS 2 a and each of other eNBs respectively. In this embodiment, signal quality related information is illustrated with signal strength. It may be understood that it is only exemplary here and signal quality related information is not limited to aforesaid contents and may be also RSSI (Received Signal Strength Indication), RSRP (Reference Signal Received Power), CQI (Channel Quality Indication) or CSI (Channel State Indication).
The MS 2 a is located at cell edge area and may detect signal strength with the serving eNB 1 a and signal strength with each of neighboring cell eNBs 1 b , 1 c , and 1 d , for example, which are 110 dBm, 92 dBm, 85 dBm and 50 dBm respectively.
Then, in step S 11 , the MS 2 a reports to eNB 1 a signal quality related information with the serving eNB 1 a and with each of a plurality of other eNBs. The signal quality related information comprises the type of the reported measurement value, which is RSSI in this embodiment, and further comprises the measured values.
Particularly, that when the MS 2 a reports may be divided into the following two manners:
event trigger:
in the phase of network entry, the MS 2 a knows that it needs to report to the serving eNB 1 a other eNBs whose signal strengths exceed a third predetermined threshold value and the signal strengths corresponding to these eNBs in order to perform collaborative MIMO among a plurality of eNBs. For example, the reported threshold pre-stored in the MS 2 a is 80 dBm, that is, when the MS 2 a detects that the signal strength corresponding to eNB exceeds 80 dBm, the MS 2 a will report to the serving eNB 1 a this eNB and the signal strength corresponding to this eNB. For example, when the MS 2 a detects that the signal strengths with neighboring cell eNBs 1 b , 1 c and 1 d are 92 dBm, 85 dBm and 50 dBm respectively, in order to reduce uplink signaling overhead and increase the reliability of collaborative MIMO, the MS 2 a only reports to the serving eNB 1 a the neighboring cell eNBs having good signal qualities, that is, the eNB whose signal strengths exceeds the third predetermined threshold, comprising: eNB 1 b and eNB 1 c , and signal strength between the MS 2 a and eNB 1 b , signal strength between the MS 2 a and eNB 1 c . Therefore, the MS 2 a reports to the serving eNB 1 a , the serving eNB 1 a and other eNBs 1 b and 1 c , whose signal strength with the MS 2 a are 110 dBm 92 dBm and 85 dBm, respectively.
Or, in a varied embodiment, it may be specified that the MS 2 a only reports the signal strength of the two neighboring cell eNBs whose measured signal strengths are the strongest. The aforesaid parameters are still taken as example, then the MS 2 a reports to the serving eNB 1 a signal strengths of the serving eNB 1 a and the two neighboring cell eNBs whose signal strengths are the strongest, which are 110 dBm, 92 dBm and 85 dBm respectively.
Furthermore, alternatively, if the uplink signaling overhead of system is not considered, once the MS 2 a detects signal from a neighboring cell eNB, it may report to the serving eNB 1 a this neighboring cell eNB and signal strength corresponding to this neighboring cell eNB, that is, the MS 2 a reports to the serving eNB 1 a all of the detected signal strengths and eNBs corresponding to these detected signal strengths. For example, the MS 2 a reports the signal strengths with the serving eNB 1 a and eNBs 1 b , 1 c , and 1 d , which are 110 dBm, 92 dBm 85 dBm and 50 dBm respectively.
periodical trigger:
the MS 2 a comprises timer for sending measurement report, when the timer reaches a predetermined time, it means that the MS 2 a needs to report to the serving eNB 1 a the detected signal quality related information of a plurality of other eNBs. For example, if the timer expires, the MS 2 a reports to the serving eNB 1 a the signal strengths between each of the serving eNB 1 a , other eNBs 1 b and 1 c and the MS 2 a , which are 110 dBm, 92 dBm and 85 dBm respectively; or the MS 2 a reports the signal strengths with each of the serving eNB 1 a , eNBs 1 b , 1 c and 1 d , which are 110 dBm, 92 dBm 85 dBm and 50 dBm respectively.
Then, in step S 12 , the serving eNB 1 a determines eNBs 1 b and 1 c as candidate eNBs according to signal quality related information reported by the MS 2 a.
Particularly, a first predetermined threshold value is pre-stored in the serving eNB 1 a , the first predetermined threshold value is used for selecting candidate eNB, desired by the serving eNB 1 a to collaboratively process service of the MS 2 a with this serving eNB 1 a , according to physical signal strength. When the serving eNB 1 a selects candidate eNB, at least the magnitude of RSSI value is considered, moreover, the serving eNB 1 a may also need to consider the difference value of signal strength between eNB 1 b and eNB 1 c.
For example, the first predetermined threshold value pre-stored in the serving eNB 1 a is 90 dBm, and a second predetermined threshold value is 10 dBm. The second predetermined threshold value is used for judging the difference level of signal strength among a plurality of other eNBs.
The aforesaid parameters are still taken as example. The serving eNB 1 a firstly judges whether signal strength from other eNBs is higher than the first predetermined threshold value 90 dBm.
if the signal strengths of both neighboring cell eNBs are higher than the first predetermined threshold value, then these two neighboring cell eNBs are both taken as candidate eNBs. For example, for the MS 2 b , as shown in FIG. 1 , the MS 2 b reports to the serving eNB 1 a the signal strengths with each of the serving eNB 1 a , other eNBs 1 d and 1 e . If the signal strengths between the MS 2 b and each of neighboring cell eNBs 1 d and 1 e , which are obtained by the serving eNB 1 a and are from the report of the MS 2 b , are 95 dBm and 105 dBm respectively, both being higher than 90 dBm, then the serving eNB 1 a takes both eNBs 1 d and 1 e as candidate eNBs. if the signal strength value of only one eNB of two neighboring cell eNBs is higher than the first predetermined threshold value, and the difference value between signal strengths of the two neighboring cell eNBs is higher than the second predetermined threshold value, then the eNB whose signal strength is higher than the first predetermined threshold value is taken as candidate eNB. For example, for the MS 2 c , as shown in FIG. 1 , the MS 2 c reports to the serving eNB 1 a the signal strengths with each of the serving eNB 1 a , other eNBs 1 b and 1 g . If the signal strengths between the MS 2 c and each of neighboring cell eNBs 1 b and 1 g , which are obtained by the serving eNB 1 a and are from the report of the MS 2 c , are 100 dBm and 80 dBm respectively, only 100 dBm being higher than 90 dBm, and the difference value of these two signal strengths is 20 dBm, higher than the second predetermined threshold value 10 dBm, then the serving eNB 1 a only takes other eNBs 1 b as candidate eNB. if the signal strength value of only one eNB of two neighboring cell eNBs is higher than the first predetermined threshold value, and the difference value between signal strengths of the two neighboring cell eNBs is less than the second predetermined threshold value, then serving eNB takes both two neighboring cell eNBs as candidate eNBs. For example, for the MS 2 a , the MS 2 a reports to the serving eNB 1 a the signal strengths with each of the serving eNB 1 a , other eNBs 1 b and 1 c . The signal strengths between the MS 2 a and each of neighboring cell eNBs 1 b and 1 c , which are obtained by the serving eNB 1 a and are from the report of the MS 2 a , are 92 dBm and 85 dBm respectively, only 92 dBm being higher than 90 dBm, and the difference value of these two signal strengths is 7 dBm, less than the second predetermined threshold value 10 dBm, then the serving eNB 1 a takes both other eNBs 1 b and 1 c as candidate eNBs. This practice broadens the limitation to signal strength of neighboring cell eNB, since the different value of respective signal strength of two neighboring cell eNBs is less the second predetermined threshold value, signal strengths are relative close to each other so that it will not cause the weaker signal to be submerged because one signal is too strong and the other is too weak.
Then, in step S 13 , the serving eNB 1 a sends resource related information request message to eNB 1 b and eNB 1 c.
In order to reduce redundant information interaction between the serving eNB 1 a and other eNBs, the serving eNB 1 a sends resource related information request message only to the candidate eNB selected by it. For example, the serving eNB 1 a sends resource related information request message to the selected candidate eNBs 1 b and 1 c . The resource related information request message is used for requesting the candidate eNBs 1 b and 1 c to send resource related information to the serving eNB 1 a . The serving eNB 1 a interacts with other eNBs via X2 interfaces.
After candidate eNB receives the resource related information request message from the serving eNB 1 a , the method goes into step S 14 , eNBs 1 b and 1 c respectively send respective resource related information to the serving eNB 1 a . The serving eNB 1 a may extract information related to available resource of eNBs 1 b and 1 c from the resource related information.
Certainly, there are at least two kinds of forms of resource related information: indication information of the occupied resource and indication information of the available resource.
Bit MAP is taken as example to illustrate resource related information. For example, the available bandwidth for each eNB is 5M, assuming multiplexing coefficient is 1, that is, each eNB may use the same frequency resource. For each eNB, for example, the allocation granularity of the bandwidth 5M is RB (Resource Block). In bit MAP, 0 denotes that the resource block is available namely idle, 1 denotes that the resource block is not available, that is, the resource block has already been allocated, or vice versa. And bit MAP is indexed to form pattern of resource related information.
For example, in respective resource related information which eNBs 1 b and 1 c respectively send to the serving eNB 1 a , the pattern of the resource related information of eNB 1 b indicates that the resource blocks number 5 to number 33 of eNB 1 b are not allocated and are still available, the pattern of the resource related information of eNB 1 c indicates that the resource blocks numbers 17 to 40 of eNB 1 c are available.
Then, in step S 15 the serving eNB 1 a determines collaborative eNB among eNBs 1 b and 1 c according to resource related information of eNBs 1 b and 1 c , and allocates corresponding communication resources.
In the following scenarios, several scenarios, in which there are common available resources among the serving eNB 1 a and each of eNBs 1 b and 1 c , are discussed respectively:
i) there is no common available resource either between the serving eNB and eNBs 1 b or between the serving eNB 1 a and eNBs 1 c:
for example, the available resources of the serving eNB 1 a are the resource blocks number 45 to number 60 , the aforesaid parameters are still taken as example, that is, the available resources of eNB 1 b are the resource blocks number 5 to number 33 , the available resources of eNB 1 c are the resource blocks number 17 to number 40 . The available resources of the serving eNB 1 a do not have intersection either with the available resources of eNB 1 b or with the available resources of eNB 1 c . Therefore, the serving eNB 1 a can not perform collaborative MIMO with neighboring cell eNB. Therefore, the method ends here, and the subsequent steps are not needed.
ii) there are same common available resources among the serving eNB 1 a , eNB 1 b and eNB 1 c:
for example, the available resources of the serving eNB 1 a are the resource blocks number 10 to number 25 , the aforesaid parameters are still taken as example, that is, the available resources of eNB 1 b are the resource blocks number 5 to number 33 , the available resources of eNB 1 c are the resource blocks number 17 to number 40 . The resource blocks number 17 to number 25 are the same common available resources among the serving eNB 1 a and eNB 1 b and eNB 1 c . Therefore, the serving eNB 1 a takes both eNB 1 b and eNB 1 c as collaborative eNBs for collaborative MIMO and allocates resources in the resource blocks number 17 to number 25 for eNB 1 b and eNB 1 c.
iii) there are respectively common available resources between the serving eNB 1 a and eNB 1 b and between the serving eNB 1 a and eNB 1 c , but the common available resources between the serving eNB 1 a and eNB 1 b does not have intersection with the common available resources between the serving eNB 1 a and eNB 1 c:
for example, the available resources of the serving eNB 1 a are the resource blocks number 10 to number 25 and the resource blocks number 50 to number 64 , the available resources of eNB 1 b are the resource blocks number 15 to number 45 , the available resources of eNB 1 c are the resource blocks number 40 to number 60 . Therefore, the resource blocks number 15 to number 25 are the common available resources between the serving eNB 1 a and eNB 1 b , the resource blocks number 50 to number 60 are the common available resources between the serving eNB 1 a and eNB 1 c , these two common available resources do not have intersection between each other. Now, the serving eNB 1 a further selects the one with better signal quality as collaborative eNB according to signal qualities of the two candidate eNBs. For example, the signal strength between eNB 1 b and the MS 2 a is 92 dBm, the signal strength between eNB 1 c and the MS 2 a is 85 dBm. Since the signal strength between eNB 1 b and the MS 2 a is higher than the signal strength between eNB 1 c and the MS 2 a , the serving eNB 1 a selects eNB 1 b as collaborative eNB.
Then, the serving eNB 1 a determines corresponding MCS (Modulation and Coding Scheme) according to QoS (Quality of Service) of the service requested by the MS 2 a , and allocates a part or all of common available resources for the serving eNB 1 a and the determined collaborative eNB according to the MCS, granularity of resource allocation, single allocation or allocation in pairs, to perform collaborative MIMO. For example, the scenario i) is taken as example, the serving eNB 1 a allocates the resource blocks number 18 to number 21 of the resource blocks number 17 to number 25 for the serving eNB 1 a , eNB 1 b and eNB 1 c , so that the serving eNB 1 a , eNB 1 b and eNB 1 c perform collaborative MIMO on the same resource blocks number 18 to number 21 , and sends collaborative MIMO request to eNB 1 b and eNB lc, which comprises the sequence number 18 - 21 of the resource blocks for collaborative MIMO, allocated for eNB 1 b and eNB 1 c by the serving eNB 1 a.
In a varied embodiment, prior to the step S 11 , the method further comprises the following step, the serving eNB 1 a sends to the MS 2 a measurement control message for requesting measurement report, the measurement control message comprises the type of the desired MS measurement and the threshold value of the reported measurement value. Then, in the step S 12 , the MS 2 a measures and reports according to the measurement control message received from the serving eNB 1 a.
In aforesaid embodiment, in the step S 11 , the serving eNB 1 a obtains the measurement report reported by the MS 2 a , the measurement report comprises not only the signal quality between the MS 2 a and the serving eNB 1 a but also the signal quality between the MS 2 a and other eNBs. In a varied embodiment, for example, for TDD system, the serving eNB 1 a may measure via uplink sounding signal and obtain corresponding downlink signal quality from uplink signal quality according to the reciprocity of TDD system, therefore, the serving eNB 1 a may measure signal quality with the MS 2 a by itself and receive signal quality related information between this MS and other eNB, reported by the MS 2 a . That is, the MS 2 a does not need to report to its serving eNB 1 a the signal quality related information between the MS 2 a and the serving eNB 1 a.
In aforesaid embodiment, existing measurement control and measurement report between each MS and serving eNB may be reused. In a varied embodiment, considering that MS develops towards the trend of more intelligent, its computing speed and process capability are higher and higher. Therefore, a kind of new signaling may be defined, or a kind of new measurement type is defined in measurement types, so the step S 12 may be finished by MS, that is, the MS 2 a judges that which neighboring cell eNBs are selected as candidate eNBs according to measurement results with the serving eNB 1 a and neighboring eNBs (for example, eNB 1 b , eNB 1 c ), measured by itself, and generates corresponding candidate eNB indication information and sends the candidate eNB indication information to serving eNB. The detailed judging process is described in aforesaid step S 12 in details, it is not necessary to repeat again. Then in step S 13 , the serving eNB 1 a sends resource related information request message to corresponding candidate eNB according to candidate eNB indication information from the MS 2 a.
In the step S 13 of aforesaid embodiment, that the serving eNB 1 a sends resource related information request message to eNB 1 b and eNB 1 c is for the purpose of reducing signaling overhead between eNB and eNB. Without considering signaling overhead, the step S 13 may be omitted, for example, neighboring eNBs may report their resource related information to the serving eNB 1 a periodically, and it is not necessary for neighboring eNBs to trigger the report upon receiving the request message from the serving eNB 1 a.
In aforesaid embodiment, the scenario in which the MS 2 a reports to the serving eNB 1 a the signal strengths between the MS 2 a and each of two neighboring cell eNBs, is taken as example for illustration. In a varied embodiment, the MS 2 b is taken as example, for example, the MS 2 b reports to the serving eNB 1 a the signal strengths between the MS 2 a and each of a plurality of neighboring cell eNBs, which comprise eNB 1 d , eNB 1 e and eNB 1 b . FIG. 4 shows a method flowchart from step S 12 to step S 15 performed by the serving eNB 1 a , taking the MS 2 b as a detailed embodiment. Hereinafter, in combination with FIG. 4 , the flowchart is described as follows:
In step S 120 , firstly, the serving eNB 1 a judges whether the signal strength between each of three neighboring cell eNBs and the MS 2 b is higher than the first predetermined threshold.
if the judging result of the serving eNB 1 a is that the signal strength between each of three neighboring cell eNBs and the MS 2 b is higher than the first predetermined threshold, then the method goes into the step S 122 ′, the serving eNB 1 a takes all of three neighboring eNBs 1 b , 1 d and 1 e as candidate eNBs for collaborative MIMO; if the judging result of the serving eNB 1 a is that not all the signal strengths from the three neighboring cell eNBs are higher than the first predetermined threshold, for example, the signal strength from eNB 1 b is less than the first predetermined threshold, but the signal strengths from eNB 1 d and eNB 1 e are higher than the first predetermined threshold, then the method goes into the step S 121 , the serving eNB 1 a judges whether the difference value between the signal strength of the one that is less than the first predetermined threshold, and the signal strength of the minimal in these signal strengths which are higher than the first predetermined threshold, is higher than the second predetermined threshold. For example, the first predetermined threshold is 90 dBm, and the second predetermined threshold is 10 dBm. The signal strengths from eNB 1 d and eNB 1 e are respectively 100 dBm and 92 dBm, and the signal strength from eNB 1 b is 88 dBm. The serving eNB 1 a firstly judges that the signal strengths from eNB 1 d and eNB 1 c are higher than the first predetermined threshold, but the signal strength from eNB 1 b is less than the first predetermined threshold, thus the serving eNB 1 a firstly takes eNBs 1 d and 1 e as candidate eNBs, then the method goes into the step S 121 , the serving eNB 1 a further compares the difference value between the signal quality from eNB 1 b and the signal quality from eNB 1 e , the serving eNB finds that the difference value of the signal quality from eNB 1 e 92 dBm minus the signal quality from eNB 1 b 88 dBm is less than the second predetermined threshold, thus the serving eNB 1 a also takes eNBs 1 b as candidate eNB; if the first predetermined threshold is 90 dBm, and the second predetermined threshold is 10 dBm, the signal strengths from eNB 1 d and eNB 1 e are respectively 100 dBm and 95 dBm, and the signal strength from eNB 1 b is 80 dBm. Then in the step S 121 , the judging result of the serving eNB 1 a is the difference value of the signal strength between eNB 1 b and MS, and the signal strength between eNB 1 e and MS is higher than the second predetermined threshold, thus in the step S 122 , the serving eNB 1 a only takes the two neighboring cell eNBs 1 d and 1 e as candidate eNBs for collaborative MIMO; furthermore, if the signal quality of only one eNB is higher than the first predetermined threshold, for example, only the signal quality of eNB 1 d is higher than the first predetermined threshold, and the difference value of signal quality between eNB 1 b and eNB 1 d , and the difference value of signal quality between eNB 1 e and eNB 1 d are both higher than the second predetermined threshold, then the judging result of the serving eNB 1 a is that only eNB 1 d is taken as candidate eNB for collaborative MIMO.
Then, in step S 13 , the serving eNB 1 a sends resource related information request message to the selected candidate eNB; then, in step S 14 , the serving eNB obtains resource related information from each candidate eNB.
Then, in step S 150 , the serving, eNB 1 a judges whether the available resources from each candidate eNB overlaps the available resources of the serving eNB 1 a.
Since the scenario with two candidate eNBs is discussed hereinbefore, it is not necessary to repeat again. Hereinafter, the scenario with three candidate eNBs, for example, eNBs 1 b , 1 d and 1 e , will be discussed, the available resources of each of three candidate eNBs may have common parts with the available resources of the serving eNB 1 a or may not.
if the available resources of each of three candidate eNBs are not same with the available resources of the serving eNB 1 a , that is, the available resources of each of three candidate eNBs do not overlap the available resources of the serving eNB 1 a , then the method goes into step S 153 ″, the serving eNB 1 a judges that all of three candidate eNBs can not cooperate with the serving eNB to perform CO-MIMO; if the available resources of each of three candidate eNBs has common parts with the available resources of the serving eNB 1 a , then in the step S 151 , the serving eNB 1 a continues to judge whether there are suitable common available resources, for example, judge whether the common available resources of a plurality of candidate eNBs and the serving eNB 1 a are partly same or identical. If the common available resources of candidate eNBs and serving eNB are shown as FIG. 5A , the same common available resources is denoted by the shadow with slash lines, then the serving eNB 1 a judges to go into step S 153 , all of the three candidate eNBs may cooperate with the serving eNB 1 a for collaborative MIMO on the same common available resources, and the serving eNB 1 a accordingly allocates a part or all of resources corresponding to the shadow with slash lines for the serving eNB 1 a and other eNBs 1 b , 1 d and 1 e ; if, for example, the common available resources between two candidate eNBs and serving eNB have overlapping parts, but there is no common available resource between another candidate eNB and serving eNB, then similarly, a part or all of the overlapping common available resources between the two candidate eNBs and the serving eNB are taken as resources for CO-MIMO; if there are common available resources between each of a plurality of candidate eNBs and the serving eNB 1 a respectively, and there is no common available resource between every two of the plurality of candidate eNBs, a candidate eNB whose signal quality with the MS is the best among the plurality of candidate eNBs is selected as collaborative eNB to cooperate with the serving eNB to serve the MS, according to the signal quality of each candidate eNB. FIG. 5B is taken as example, each of candidate eNB 1 e and 1 b has common available resources with the serving eNB 1 a , but there is no same part between the two common available resources, then in step S 153 ′, the serving eNB 1 a selects a candidate eNB whose signal quality with the MS 2 b is the best among candidate eNBs as collaborative eNB to cooperate with the serving eNB 1 a . For example, the signal strength between eNB 1 e and the MS 2 b is 95 dBm and the signal strength between eNB 1 b and the MS 2 b is 88 dBm, then the serving eNB 1 a selects eNB 1 c as collaborative eNB, and selects a part or all of the common available resource, as shown by the shadow with transverse line in FIG. 5B , for the serving eNB 1 a and collaborative eNB 1 e to perform CO-MIMO; if there are common available resources between not all of candidate eNBs 1 b , 1 d and 1 e , and the serving eNB 1 a , for example, as shown in FIG. 5C , candidate eNBs 1 d and 1 b have common available resources with the serving eNB 1 a , as shown by the shadow with slash lines, and candidate eNB 1 e has common available resources with the serving eNB 1 a , as shown by the shadow with transverse lines, and these two common available resources have no intersection with each other, then in the step S 153 ′ the serving eNB 1 a takes each candidate eNB, corresponding to common available resources available for allocation for the maximum number of candidate eNBs and for the serving eNB, as collaborative eNB to cooperate with the serving eNB 1 a to serve the MS 2 b , that is, as shown in FIG. 5C , the serving eNB 1 a takes eNBs 1 d and 1 b as collaborative eNBs, and allocates the resources for CO-MIMO for the serving eNB 1 a , collaborative eNB 1 b and collaborative eNB 1 d according to corresponding common available resources shown by the shadow with slash lines.
It may be understood that the above-mentioned values of the first predetermined threshold, the second predetermined threshold and the third predetermined threshold are only exemplary, those skilled in the art may select suitable threshold values according to actual engineering requirement such as different network configuration. Furthermore, the values of signals in each embodiment are also only exemplary.
Hereinbefore, the embodiments of the present invention are described in detail from the aspect of method; hereinafter, the embodiments of the present invention are described in detail from the aspect of device. FIG. 6 shows a block diagram of device of a detailed embodiment of the present invention.
Wherein, a first collaborative device 1 of serving eNB 1 a , for allocating communication resources for the serving eNB and one or more collaborative eNBs that collaboratively process mobile station service, comprises a means 10 for determining candidate eNB, a means 11 for requesting, a means 12 for obtaining resource information and a means 13 for processing. Wherein, the means 10 for determining candidate eNB further comprises a means 100 for obtaining signal quality, the means 13 for processing further comprises a means 130 for resource judging and a means 131 for resource allocation.
An assisting device 2 of the MS 2 a , for assisting a serving eNB in allocating communication resources for the serving eNB and one or more collaborative eNBs that collaboratively process mobile station service, comprises a means 20 for measurement, a means 21 for sending.
A second collaborative device 3 of the candidate eNBs 1 b , 1 c , for assisting the serving eNB in allocating communication resources for the serving eNB and one or more collaborative eNBs that collaboratively process mobile station service, comprises: a means 30 for receiving request, a means 31 for sending resource information, a means 32 for obtaining indication and a means 33 for communication.
The means 20 for measurement of the assisting device 2 of the MS 2 a measures signal quality related information between the MS 2 a and the serving eNB 1 a , and between the MS 2 a and each of other eNBs respectively. In this embodiment, signal quality related information is illustrated with signal strength. It may be understood that it is only exemplary here and signal quality related information is not limited to aforesaid contents and may be also RSSI (Received Signal Strength Indication), RSRP (Reference Signal Received Power), CQI (Channel Quality Indication) or CSI (Channel State Indication).
The MS 2 a is located at cell edge area, the means 20 for measurement may detect signal strength with the serving eNB 1 a and signal strength with each of neighboring cell eNBs 1 b , 1 c , and 1 d , for example, which are 110 dBm, 92 dBm, 85 dBm and 50 dBm respectively.
Then, the means 21 for sending reports to the means 100 for obtaining signal quality of the eNB 1 a signal quality related information with the serving eNB 1 a and with each of a plurality of other eNBs. The signal quality related information comprises the type of the reported measurement value, which is RSSI in this embodiment, and further comprises the measured values.
Particularly, that when the MS 2 a reports may be divided into the following two manners of:
event trigger:
in the phase of network entry, the MS 2 a knows that it needs to report to the means 100 for obtaining signal quality of the serving eNB 1 a other eNBs whose signal strengths exceed a third predetermined threshold value and the signal strengths corresponding to these eNBs in order to perform collaborative MIMO among a plurality of eNBs. For example, the reported threshold pre-stored in the MS 2 a is 80 dBm, that is, when the means 20 for measurement detects that the signal strength corresponding to eNB exceeds 80 dBm, the means 20 for measurement will report to the serving eNB 1 a this eNB and the signal strength corresponding to this eNB. For example, when the means 20 for measurement detects that the signal strengths with neighboring cell eNBs 1 b , 1 c and 1 d are 92 dBm, 85 dBm and 50 dBm respectively, in order to reduce uplink signaling overhead and increase the reliability of collaborative MIMO, the means 21 for sending only reports to the serving eNB 1 a the neighboring cell eNBs having good signal qualities, that is, the eNB whose signal strengths exceeds the third predetermined threshold, comprising: eNB 1 b and eNB 1 c , and signal strength between the MS 2 a and eNB 1 b , signal strength between the MS 2 a and eNB 1 c . Therefore, the means 21 for sending reports to the serving eNB 1 a , the serving eNB 1 a and other eNBs 1 b and 1 c , whose signal strength with the MS 2 a are 110 dBm 92 dBm and 85 dBm, respectively.
Or, in a varied embodiment, it may be specified that the MS 2 a only reports the signal strength of the two neighboring cell eNBs whose measured signal strengths are the strongest. The aforesaid parameters are still taken as example, then the means 21 for sending reports to the serving eNB 1 a signal strengths of the serving eNB 1 a and the two neighboring cell eNBs whose signal strengths are the strongest, which are 110 dBm, 92 dBm and 85 dBm respectively.
Furthermore, alternatively, if the uplink signaling overhead of system is not considered, once the MS 2 a detects signal from a neighboring cell eNB, it may report to the serving eNB 1 a this neighboring cell eNB and signal strength corresponding to this neighboring cell eNB, that is, the MS 2 a reports to the serving eNB 1 a all of the detected signal strengths and eNBs corresponding to these detected signal strengths. For example, the MS 2 a reports the signal strengths with the serving eNB 1 a and eNBs 1 b , 1 c , and 1 d , which are 110 dBm, 92 dBm 85 dBm and 50 dBm respectively.
periodical trigger:
the MS 2 a comprises timer for sending measurement report, when the timer reaches a predetermined time, it means that the MS 2 a needs to report to the means 100 for obtaining signal quality of the serving eNB 1 a the detected signal quality related information of a plurality of other eNBs. For example, if the timer expires, the means 21 for sending reports to the means 100 for obtaining signal quality of the serving eNB 1 a the signal strengths between each of the serving eNB 1 a , other eNBs 1 b and 1 c and the MS 2 a , which are 110 dBm, 92 dBm and 85 dBm respectively; or the means 21 for sending reports the signal strengths with each of the serving eNB 1 a , eNBs 1 b , 1 c and 1 d , which are 110 dBm, 92 dBm 85 dBm and 50 dBm respectively.
The means 10 for determining candidate eNB, of the first collaborative device 1 of the serving eNB 1 a , determines eNBs 1 b and 1 c as candidate eNBs according to signal quality related information reported by the MS 2 a.
Particularly, a first predetermined threshold value is pre-stored in the means 10 for determining candidate eNB, the first predetermined threshold value is used for selecting candidate eNB, desired by the serving eNB 1 a to collaboratively process service of the MS 2 a with this serving eNB 1 a , according to physical signal strength. When the means 10 for determining candidate eNB selects candidate eNB, at least the magnitude of RSSI value is considered, moreover, the means 10 for determining candidate eNB may also need to consider the difference value of signal strength between eNB 1 b and eNB 1 c.
For example, the first predetermined threshold value pre-stored in the means 10 for determining candidate eNB is 90 dBm, and a second predetermined threshold value is 10 dBm. The second predetermined threshold value is used for judging the difference level of signal strength among a plurality of other eNBs.
The aforesaid parameters are still taken as example. The means 10 for determining candidate eNB firstly judges whether signal strength from other eNBs is higher than the first predetermined threshold value 90 dBm.
if the signal strengths of both neighboring cell eNBs are higher than the first predetermined threshold value, then these two neighboring cell eNBs are both taken as candidate eNBs. For example, for the MS 2 b , as shown in FIG. 1 , the MS 2 b reports to the serving eNB 1 a the signal strengths with each of the serving eNB 1 a , other eNBs 1 d and 1 e . If the signal strengths between the MS 2 b and each of neighboring cell eNBs 1 d and 1 e , which are obtained by the means 100 for obtaining signal quality and are from the report of the MS 2 b , are 95 dBm and 105 dBm respectively, both being higher than 90 dBm, then the means 10 for determining candidate eNB takes both eNBs 1 d and 1 e as candidate eNBs. if the signal strength value of only one eNB of two neighboring cell eNBs is higher than the first predetermined threshold value, and the difference value between signal strengths of the two neighboring cell eNBs is higher than the second predetermined threshold value, then the means 10 for determining candidate eNB only takes the eNB, whose signal strength is higher than the first predetermined threshold value, as candidate eNB. For example, for the MS 2 c , as shown in FIG. 1 , the MS 2 c reports to the serving eNB 1 a the signal strengths with each of the serving eNB 1 a , other eNBs 1 b and 1 g . If the signal strengths between the MS 2 c and each of neighboring cell eNBs 1 b and 1 g , which are obtained by the means 100 for obtaining signal quality and are from the report of the MS 2 c , are 100 dBm and 80 dBm respectively, only 100 dBm being higher than 90 dBm, and the difference value of these two signal strengths is 20 dBm, higher than the second predetermined threshold value 10 dBm, then the means 10 for determining candidate eNB only takes other eNBs 1 b as candidate eNB. if the signal strength value of only one eNB of two neighboring cell eNBs is higher than the first predetermined threshold value, and the difference value between signal strengths of the two neighboring cell eNBs is less than the second predetermined threshold value, then the means 10 for determining candidate eNB takes both two neighboring cell eNBs as candidate eNBs. For example, for the MS 2 a , the MS 2 a reports to the serving eNB 1 a the signal strengths with each of the serving eNB 1 a , other eNBs 1 b and 1 c . The signal strengths between the MS 2 a and each of neighboring cell eNBs 1 b and 1 c , which are obtained by the means 100 for obtaining signal quality and are from the report of the MS 2 a , are 92 dBm and 85 dBm respectively, only 92 dBm being higher than 90 dBm, and the difference value of these two signal strengths is 7 dBm, less than the second predetermined threshold value 10 dBm, then the means 10 for determining candidate eNB takes both other eNBs 1 b and 1 c as candidate eNBs. This practice broadens the limitation to signal strength of neighboring cell eNB, since the different value of respective signal strength of two neighboring cell eNBs is less the second predetermined threshold value, signal strengths are relative close to each other so that it will not cause the weaker signal to be submerged because one signal is too strong and the other is too weak.
Then, the means 11 for requesting sends resource related information request message to eNB 1 b and eNB 1 c.
In order to reduce redundant information interaction between the serving eNB 1 a and other eNBs, the means 11 for requesting sends resource related information request message only to the candidate eNB selected by it. For example, the means 11 for requesting sends resource related information request message to the selected candidate eNBs 1 b and 1 c . The resource related information request message is used for requesting the candidate eNBs 1 b and 1 c to send resource related information to the serving eNB 1 a . The means 11 for requesting interacts with other eNBs via X2 interfaces.
After the means 30 for receiving request of the second collaborative device 3 of the candidate eNBs 1 b , 1 c receives the resource related information request message from the serving eNB 1 a , their means 31 for sending resource information respectively send respective resource related information to the serving eNB 1 a . The means 12 for obtaining resource information, of the serving eNB 1 a , may extract information related to available resource of eNBs 1 b and 1 c from the resource related information.
Certainly, there are at least two kinds of forms of resource related information: indication information of the occupied resource and indication information of the available resource.
Bit MAP is taken as example to illustrate resource related information. For example, the available bandwidth for each eNB is 5M, assuming multiplexing coefficient is 1, that is, each eNB may use the same frequency resource. For each eNB, for example, the allocation granularity of bandwidth 5M is RB (Resource Block). In hit MAP, 0 denotes that the resource block is available namely idle, 1 denotes that the resource block is not available, that is, the resource block has already been allocated, or vice versa. And bit MAP is indexed to form pattern of resource related information.
For example, in respective resource related information which eNBs 1 b and 1 c respectively send to the serving eNB 1 a , the pattern of the resource related information of eNB 1 b indicates that the resource blocks number 5 to number 33 of eNB 1 b are not allocated and are still available, the pattern of the resource related information of eNB 1 c indicates that the resource blocks numbers 17 to 40 of eNB 1 c are available.
The means 13 for processing of the first collaborative device 1 determines collaborative eNB among eNBs 1 b and 1 c according to resource related information of eNBs 1 b and 1 c , and allocates corresponding communication resources.
In the following scenarios, several judging scenarios judged by the means 130 for resource judging, in which there are common available resources among the serving eNB 1 a and each of eNBs 1 b and 1 c , are discussed respectively:
i) there is no common available resource either between the serving eNB 1 a and eNBs 1 b or between the serving eNB 1 a and eNBs 1 c:
for example, the available resources of the serving eNB 1 a are the resource blocks number 45 to number 60 , the aforesaid parameters are still taken as example, that is, the available resources of eNB 1 b are the resource blocks number 5 to number 33 , the available resources of eNB 1 c are the resource blocks number 17 to number 40 . The available resources of the serving eNB 1 a do not have intersection either with the available resources of eNB 1 b or with the available resources of eNB 1 c . Therefore, the serving eNB 1 a can not perform collaborative MIMO with neighboring cell eNB.
ii) there are same common available resources among the serving eNB 1 a , eNB 1 b and eNB 1 c:
for example, the available resources of the serving eNB 1 a are the resource blocks number 10 to number 25 , the aforesaid parameters are still taken as example, that is, the available resources of eNB 1 b are the resource blocks number 5 to number 33 , the available resources of eNB 1 c are the resource blocks number 17 to number 40 . The resource blocks number 17 to number 25 are the same common available resources among the serving eNB 1 a and eNB 1 b and eNB 1 c . Therefore, the means 13 for processing takes both eNB 1 b and eNB 1 c as collaborative eNBs for collaborative MIMO, and the means 131 for resource allocation of the means 13 for processing allocates resources in the resource blocks number 17 to number 25 for eNB 1 b and eNB 1 c.
iii) there are respectively common available resources between the serving eNB 1 a and eNB 1 b and between the serving eNB 1 a and eNB 1 c , but the common available resources between the serving eNB 1 a and eNB 1 b does not have intersection with the common available resources between the serving eNB 1 a and eNB 1 c:
for example, the available resources of the serving eNB 1 a are the resource blocks number 10 to number 25 and the resource blocks number 50 to number 64 , the available resources of eNB 1 b are the resource blocks number 15 to number 45 , the available resources of eNB 1 c are the resource blocks number 40 to number 60 . Therefore, the resource blocks number 15 to number 25 are the common available resources between the serving eNB 1 a and eNB 1 b , the resource blocks number 50 to number 60 are the common available resources between the serving eNB 1 a and eNB 1 c , these two common available resources do not have intersection between each other. Now, the serving eNB 1 a further selects the one with better signal quality as collaborative eNB according to signal qualities of the two candidate eNBs. For example, the signal strength between eNB 1 b and the MS 2 a is 92 dBm, the signal strength between eNB 1 c and the MS 2 a is 85 dBm. Since the signal strength between eNB 1 b and the MS 2 a is higher than the signal strength between eNB 1 c and the MS 2 a , the means 13 for processing selects eNB 1 b as collaborative eNB.
Then, the serving eNB 1 a determines corresponding MCS (Modulation and Coding Scheme) according to QoS (Quality of Service) of the service requested by the MS 2 a , and allocates a part or all of common available resources for the serving eNB 1 a and the determined collaborative eNB according to the MCS, granularity of resource allocation, single allocation or allocation in pairs, to perform collaborative MIMO. For example, the scenario i) is taken as example, the means 131 for resource allocation allocates the resource blocks number 18 to number 21 of the resource blocks number 17 to number 25 for the serving eNB 1 a , eNB 1 b and eNB 1 c , so that the serving eNB 1 a , eNB 1 b and eNB 1 c perform collaborative MIMO on the same resource blocks number 18 to number 21 , and sends collaborative MIMO request to eNB 1 b and eNB 1 c , which comprises the sequence number 18 - 21 of the resource blocks for collaborative MIMO, allocated for eNB 1 b and eNB 1 c by the serving eNB 1 a.
Then, the means 32 for obtaining indication, of the second collaborative device 3 , obtains resource allocation indication message from the first collaborative device, the resource allocation indication message is used for indicating this candidate eNB as collaborative eNB and indicating corresponding communication resource allocated for the collaborative eNB; and the means 33 for communication, determines this candidate eNB as collaborative eNB to cooperate with the serving eNB to serve the MS 2 a , according to the resource allocation indication message obtained by the means 32 for obtaining indication, and cooperates with the serving eNB to serve the MS with the corresponding communication resource.
In a varied embodiment, the first collaborative device 1 sends to the MS 2 a measurement control message for requesting measurement report, the measurement control message comprises the type of the desired MS measurement and the threshold value of the reported measurement value. Then, the means 20 for measurement of the MS 2 a measures and reports according to the measurement control message received from the serving eNB 1 a.
In aforesaid embodiment, the means 10 for determining candidate eNB of the serving eNB 1 a obtains the measurement report reported by the MS 2 a , the measurement report comprises not only the signal quality between the MS 2 a and the serving eNB 1 a but also the signal quality between the MS 2 a and other eNBs. In a varied embodiment, for example, for TDD system, the serving eNB 1 a may measure via uplink sounding signal and obtain corresponding downlink signal quality from uplink signal quality according to the reciprocity of TDD system, therefore, the serving eNB 1 a may measure signal quality with the MS 2 a by itself and receive signal quality related information between this MS and other eNB, reported by the MS 2 a . That is, the MS 2 a does not need to report to its serving eNB 1 a the signal quality related information between the MS 2 a and the serving eNB 1 a.
In aforesaid embodiment, existing measurement control and measurement report between each MS and serving eNB may be reused. In a varied embodiment, considering that MS develops towards the trend of more intelligent, its computing speed and process capability are higher and higher. Therefore, a kind of new signaling may be defined, or a kind of new measurement type is defined in measurement types, so the MS comprises a means for recommendation (not shown in Fig), for judging that which neighboring cell eNBs are selected as candidate eNBs according to measurement results with the serving eNB 1 a and neighboring eNBs (for example, eNB 1 b , eNB 1 c ), measured by itself, and generating corresponding candidate eNB indication information and sends the candidate eNB indication information to the means 10 for determining candidate eNB of the first collaborative device 1 . The detailed judging process is described in details hereinbefore, it is not necessary to repeat again. Then, the means 12 for obtaining resource information of the eNB sends resource related information request message to corresponding candidate eNB according to candidate eNB indication information from the MS 2 a.
That the means 11 for requesting sends resource related information request message to eNB 1 b and eNB 1 c is for the purpose of reducing signaling overhead between eNB and eNB. Without considering signaling overhead, the means 11 for requesting may be omitted, example, neighboring eNBs may report their resource related information to the means 12 for obtaining resource information of the serving eNB 1 a periodically, and it is not necessary for neighboring eNBs to trigger the report upon receiving the request message from the means 11 for requesting.
In aforesaid embodiment, the scenario in which the MS 2 a reports to the serving eNB 1 a the signal strengths between the MS 2 a and each of two neighboring cell eNBs, is taken as example for illustration. In a varied embodiment, the MS 2 b is taken as example, for example, the MS 2 b reports to the serving eNB 1 a the signal strengths between the MS 2 a and each of a plurality of neighboring cell eNBs, which comprise eNB 1 d , eNB 1 e and eNB 1 b . Hereinafter, the first collaborative device 1 is described as follows according to another embodiment:
Firstly, the means 10 for determining candidate eNB firstly judges whether the signal strength between each of three neighboring cell eNBs and the MS 2 b is higher than the first predetermined threshold.
if the judging result of the means 10 for determining candidate eNB is that the signal strength between each of three neighboring cell eNBs and the MS 2 b is higher than the first predetermined threshold, then it takes all of three neighboring eNBs 1 b , 1 d and 1 e as candidate eNBs for collaborative MIMO; if the judging result of the means 10 for determining candidate eNB is that not all the signal strengths from the three neighboring cell eNBs are higher than the first predetermined threshold, for example, the signal strength from eNB 1 b is less than the first predetermined threshold, but the signal strengths from eNB 1 d and eNB 1 e are higher than the first predetermined threshold, the means 10 for determining candidate eNB judges whether the difference value between the signal strength of the one that is less than the first predetermined threshold, and the signal strength of the minimal in these signal strengths which are higher than the first predetermined threshold, is higher than the second predetermined threshold. For example, the first predetermined threshold is 90 dBm, and the second predetermined threshold is 10 dBm. The signal strengths from eNB 1 d and eNB 1 e are respectively 100 dBm and 92 dBm, and the signal strength from eNB 1 b is 88 dBm. The means 10 for determining candidate eNB firstly judges that the signal strengths from eNB 1 d and eNB 1 e are higher than the first predetermined threshold, but the signal strength from eNB 1 b is less than the first predetermined threshold, thus the means 10 for determining candidate eNB firstly takes eNBs 1 d and 1 e as candidate eNBs, then the serving eNB 1 a further compares the difference value between the signal quality from eNB 1 b and the signal quality from eNB 1 e , the serving eNB finds that the difference value of the signal quality from eNB 1 e 92 dBm minus the signal quality from eNB 1 b 88 dBm is less than the second predetermined threshold, thus the means 10 for determining candidate eNB also takes eNBs 1 b as candidate eNB; if the first predetermined threshold is 90 dBm, and the second predetermined threshold is 10 dBm, the signal strengths from eNB 1 d and eNB 1 e are respectively 100 dBm and 95 dBm, and the signal strength from eNB 1 b is 80 dBm. Then the judging result of the means 10 for determining candidate eNB is that the difference value of the signal strength between eNB 1 b and MS, and the signal strength between eNB 1 e and MS is higher than the second predetermined threshold, thus the means 10 for determining candidate eNB only takes the two neighboring cell eNBs 1 d and 1 e as candidate eNBs for collaborative MIMO; furthermore, if the signal quality of only one eNB is higher than the first predetermined threshold, for example, only the signal quality of eNB 1 d is higher than the first predetermined threshold, and the difference value of signal quality between eNB 1 b and eNB 1 d , and the difference value of signal quality between eNB 1 e and eNB 1 d are both higher than the second predetermined threshold, then the judging result of the means 10 for determining candidate eNB is that only eNB 1 d is taken as candidate eNB for collaborative MIMO.
Then, the means 11 for requesting of the serving eNB 1 a sends resource related information request message to the selected candidate eNB; then, means 12 for obtaining resource related information obtains resource related information from each candidate eNB.
Then, the means 130 for resource judging of the means 13 for processing of the serving eNB 1 a judges whether the available resources from each candidate eNB overlaps the available resources of the serving eNB 1 a.
Since the scenario with two candidate eNBs is discussed hereinbefore, it is not necessary to repeat again. Hereinafter, the scenario with three candidate eNBs, for example, eNBs 1 b , 1 d and 1 e , will be discussed, the available resources of each of three candidate eNBs may have common parts with the available resources of the serving eNB 1 a or may not.
if the available resources of each of three candidate eNBs are not same with the available resources of the serving eNB 1 a , that is, the available resources of each of three candidate eNBs do not overlap the available resources of the serving eNB 1 a , the means 130 for resource judging judges that all of three candidate eNBs can not cooperate with the serving eNB to perform CO-MIMO; if the available resources of each of three candidate eNBs has common parts with the available resources of the serving eNB 1 a , then the means 130 for resource judging continues to judge whether there are suitable common available resources, for example, judge whether the common available resources of a plurality of candidate eNBs and the serving eNB 1 a are partly same or identical. If the common available resources of candidate eNBs and serving eNB are shown as FIG. 5A , the same common available resources is denoted by the shadow with slash lines, then the means 130 for resource judging judges all of the three candidate eNBs may cooperate with the serving eNB 1 a for collaborative MIMO on the same common available resources, and the serving eNB 1 a accordingly allocates a part or all of resources corresponding to the shadow with slash lines for the serving eNB 1 a and other eNBs 1 b , 1 d and 1 e ; if for example, the common available resources between two candidate eNBs and serving eNB have overlapping parts, but there is no common available resource between another candidate eNB and serving eNB, then similarly, a part or all of the overlapping common available resources between the two candidate eNBs and the serving eNB are taken as resources for CO-MIMO; if there are common available resources between each of a plurality of candidate eNBs and the serving eNB 1 a respectively, and there is no common available resource between every two of the plurality of candidate eNBs, a candidate eNB whose signal quality with the MS is the best among the plurality of candidate eNBs is selected as collaborative eNB to cooperate with the serving eNB to serve the MS, according to the signal quality of each candidate eNB. FIG. 5B is taken as example, each of candidate eNB 1 e and 1 b has common available resources with the serving eNB 1 a , but there is no same part between the two common available resources, then the means 13 for processing selects a candidate eNB whose signal quality with the MS 2 b is the best among candidate eNBs as collaborative eNB to cooperate with the serving eNB 1 a . For example, the signal strength between eNB 1 e and the MS 2 b is 95 dBm and the signal strength between eNB 1 b and the MS 2 b is 88 dBm, then the serving eNB 1 a selects eNB 1 e as collaborative eNB, and selects a part or all of the common available resource, as shown by the shadow with transverse line in FIG. 5B , for the serving eNB 1 a and collaborative eNB 1 e to perform CO-MIMO; if there are common available resources between not all of candidate eNBs 1 b , 1 d and 1 e , and the serving eNB 1 a , for example, as shown in FIG. 5C , candidate eNBs 1 d and 1 b have common available resources with the serving eNB 1 a , as shown by the shadow with slash lines, and candidate eNB 1 e has common available resources with the serving eNB 1 a , as shown by the shadow with transverse lines, and these two common available resources have no intersection with each other, then the means 13 for processing takes each candidate eNB, corresponding to common available resources available for allocation for the maximum number of candidate eNBs and for the serving eNB, as collaborative eNB to cooperate with the serving eNB 1 a to serve the MS 2 b , that is, as shown in FIG. 5C , the serving eNB 1 a takes eNBs 1 d and 1 b as collaborative eNBs, and allocates the resources for CO-MIMO for the serving eNB 1 a , collaborative eNB 1 b and collaborative eNB 1 d according to corresponding common available resources shown by the shadow with slash lines.
The embodiments of the present invention have been described above, but the present invention is not limited to a specific system, equipment and specific protocol, those skilled in the art may make variation and modification within the scope of the appended claims. | The present invention provides a method and device for allocating same resource for a plurality of eNBs of collaborative Multiple-input-Multiple-output (MIMO). Wherein a serving eNB firstly determines, in the one or more other eNBs, at least one candidate eNB recommended to cooperate with the serving eNB, according to measurement report reported by mobile stations or according to report information of the recommended candidate eNB reported by mobile station, then obtains resource related information of the at least one candidate eNB, then determines one or more collaborative eNBs from the at least one candidate eNB according to the resource related information, and allocates corresponding communication resources for the serving eNB and the one or more collaborative eNBs. The solution according to the present does not need to reserve special resource for collaborative MIMO, reduces waste of resource, and meets the requirement of resource for implementing collaborative MIMO by different serving eNBs flexibly, and increases the success rate of implementing collaborative MIMO. | 7 |
FIELD OF THE INVENTION
The invention pertains to a supply-roll sensing apparatus and, more particularly, to a sensing mechanism that is designed to detect and indicate a low-paper condition for receipt-printing machines that use a floating or "throw-in" roll of supply paper that is not rotationally anchored in the printer's paper-supply bucket.
BACKGROUND OF THE INVENTION
Retail receipt-printing machines are small devices that print sales receipts and validate customers'checks at sales counters. While these types of machines are generally placed on horizontal surfaces (such as desktops), they may also be located in other orientations (such as substantially vertically, when wall-mounted). Typical machines of this type are Model Nos. 7193 and 7156, manufactured by Axiohm Corporation of Ithaca, N.Y. Such a receipt-printing machine prints a receipt on paper that is fed from a relatively small, cylindrical, supply roll which is located in a hollow bucket or paper well. The bucket of this receipt-printing machine is designed to receive the cylindrical supply roll therein, without any rotational restraints (such as axles, spindles or anchors) to support the inner support core thereof. In other words, the supply roll is designed to float within the bucket. A floating supply-roll design allows the roll to shift within the bucket, depending on the orientation of the machine. Such an arrangement is often referred to as "throw-in" paper loading.
Problems exist in designing a low-paper sensing mechanism for the floating supply roll. One difficulty in designing such a sensor is that the optical sensing is dependent upon the location of the supply roll. In addition to shifts in the static roll position within the bucket (which are caused by different printer orientations), the lack of any roll-mounting support system allows the supply-paper roll to be subject to jumping and bouncing within the bucket, while it feeds paper.
Although the printer can be mounted in any number of positions, the Axiohm Model Nos. 7193 and 7156 are generally positioned in one of three orientations: on a substantially level surface, such as a desktop; at an angle of approximately 14° with the horizontal plane; and vertically, mounted on a wall. Each of these three mounting orientations obviously creates a different supply-roll position within the bucket. Two of the floating rest positions result from mounting the printing machine on a desktop. In one orientation, the base of the printer is disposed at a 14° angle with respect to the horizontal plane. In the other orientation, the printer base is substantially flat with respect to the horizontal plane. Thus, depending upon the printer orientation, the desktop-oriented machine naturally has its supply roll floating either at 14° off-center or at the center of the bucket. In a wall-mounted system, the paper roll shifts to the far side of the bucket. Therefore, placing a sensor adjacent the bucket to sense a low-paper condition for all three different mounting orientations is problematical. To accommodate additional, possible printer-mounting orientations represents an enormous problem. A sensor (e.g., a photosensing device) must be able to read the supply-roll condition, regardless of printer orientation.
It is not an easy task to design a reflective photosensing mechanism that can sense an object which changes its position with respect to the sensor mounting. When the supply roll moves beyond the eye of the sensor's reflective beam, the sensor is unable to assess the low-paper condition of the supply roll.
The present invention reflects the discovery that a specially adapted photosensor, when combined with appropriate, software-operated controls, can reliably sense a low-paper condition, irrespective of the floating supply roll's position in the bucket. Additionally, the inventive software-based techniques provide reliable, low-paper indications, despite the bouncing and jumping of the unrestrained paper-roll within the paper-bucket.
DISCUSSION OF RELATED ART
A typical, roll-end detector is illustrated in Pat. No. 3,709,604 (issued to NIESEN et al on Jan. 9, 1973). The beam-reflective detector is fixed to a stationary mount, as are most such detectors. A reflective beam is directed at a supply roll. When the supply roll empties to the point at which the roll's supportive core is bare, the angle of the reflected beam becomes coincident with the angle at which the detector's eye is focused. Such a device naturally requires a fixed mounting position, in order to create an optical alignment of beam and eye.
The present invention differs from the above patented device in that its mounting position can vary, and yet it is still able to provide the necessary optical alignment for low supply-roll sensing. In addition, for a specified printer orientation, the photosensing device of this invention is uniquely adjustable to the position of the supply roll resting within its bucket.
SUMMARY OF THE INVENTION
In accordance with the present invention, there is provided a photosensing mechanism that senses a low condition of a paper-supply roll housed within a receipt-printing machine. The paper supply roll has a "floating" characteristic; that is, no fixed rotational mechanism aligns the roll within its feed bucket. The photosensing mechanism of this invention may be adjusted to several predetermined positions, so as to accommodate different supply-roll positions within the feed bucket, with differing positions resulting from different orientations of the receipt-printing machine.
The present invention features an easily adjustable, photosensing mechanism that may be preset to accommodate different supply-roll positions within the bucket of the receipt-printing machine. In addition, a software-implemented, "de-bounce" strategy is employed, so as to ensure against false positive indications (i.e., to help ascertain that the low-paper condition exists, due to the possibility of supply-roll bouncing within the bucket).
The photosensor of this invention uses a reflective beam and eye arrangement mounted on an arcuate bracket rail that is affixed to the supply bucket. The bracket rail allows the photosensor to be arcuately shifted therealong. A friction pad mounted upon the surface of the photosensor provides sufficient friction to hold the photosensor assembly in position during normal machine operation, while also allowing for easy adjustment when necessary. This movable arrangement allows the low-paper function to perform predictably with the machine, when the latter may be in a variety of orientations; the photosensor can be appropriately adjusted to accommodate resulting variations in the paper supply-roll position in the bucket. Another advantage of the shiftable photosensor is that a customer may make a simple, positional adjustment in order to receive an earlier or later warning of a low-paper condition, if suitable for their needs.
A photo beam of the photosensor reflects off the side of the paper roll; it is sensed by the photosensor's eye. The sensor indicates when the roll is becoming low, because the photo beam fails to reflect off the roll when the size of the supply roll disappears past the eye of the beam. When the paper nears the depletion state, the beam will miss the remainder of the roll, and thus will not be reflected. Minor adjustments of the photosensor may be made to determine at what particular point in the remainder of the paper a low-paper signal will be issued. Reliable operation of the low-paper detection system of the present invention is ensured by the use of "de-bounce" sampling software. This de-bounce software only provides a low-paper warning signal after a predetermined number of samples of the reflective photosensor have been registered.
BRIEF DESCRIPTION OF THE DRAWINGS
A complete understanding of the present invention may be obtained by reference to the accompanying drawings, when considered in conjunction with the subsequent, detailed description, in which:
FIG. 1 illustrates a front view of the photosensing mechanism of this invention;
FIG. 2 depicts a back view of the photosensing mechanism shown in FIG. 1;
FIG. 3 illustrates a bucket orientation that results from positioning the receipt-printing machine at 14° with respect to the horizontal plane;
FIG. 4 illustrates a bucket orientation that results from positioning the receipt-printing machine at 0° with respect to the horizontal plane;
FIG. 5 illustrates a bucket orientation that results from positioning the receipt-printing machine at 90° with respect to the horizontal plane;
FIG. 6 shows an enlarged view of a supply bucket, a supply roll and the inventive photosensing device, with phantom views of the supply roll and photosensing device in three different positions;
FIG. 7 is a flowchart of the "de-bounce" software of the low-paper detection system Of the present invention; and
FIG. 8 is a flowchart of an alternate embodiment of the de-bounce software of the low-paper detection system of the present invention.
For purposes of clarity and brevity, like elements and components will bear the same designations and numbering throughout the FIGURES.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Generally speaking, the invention features a sensing mechanism for a receipt-printing machine. The sensing mechanism is able to determine when a supply roll of paper is near depletion. The paper roll is deposited in a supply bucket without any rotational restraints, so that the paper roll is floating within the bucket chamber. The receipt-printing machine can be mounted in several different orientations, each of which alters the position that the supply roll occupies within the bucket. The sensing mechanism may be easily adjusted to accommodate the various positions that the supply roll assumes inside the bucket.
Now referring to FIG. 1, a front view of the photosensing mechanism 10 of this invention is shown. The photosensing mechanism 10 comprises a reflective sensing unit 11 that has a light-emitting diode (LED) 12 which directs a light beam 14 upon the side 18 of an adjacently disposed supply roll 15. The light beam 14 normally bounces off the side 18 of the supply roll 15, when the wound supply roll 15 contains at least a minimum amount of paper. The reflected light beam 14' from the supply roll 15 is received by the eye 16 of the reflective sensing unit 11.
The reflective sensing unit 11 is movably mounted upon an arcuate bracket rail 17. A friction pad 19 is mounted upon the outer surface of the reflective sensing unit 11. The friction pad 19 provides sufficient friction between the reflective sensing unit 11 and the arcuate bracket rail 17 to hold the reflective sensing unit 11 in position during normal printer operation. The friction is small enough, however, to allow for easy movement of the reflective sensor unit 11 with respect to the arcuate bracket rail 17 during factory or field adjustment, as described hereinbelow.
Referring to FIG. 2, the arcuate bracket rail 17 is disposed in a conforming, arcuate channel 17' that is disposed on the back of the reflective sensing unit 11, as shown. The arcuate channel 17' allows the reflective sensing unit 11 to slide along the arcuate bracket rail 17 in either a clockwise or counterclockwise direction, as shown by arrows 20. The arcuate bracket rail 17 is mounted to a wall 21 of the housing of the supply bucket (not shown) by a pair of screws 22, respectively disposed on distal ends "A" and "B" of the arcuate bracket rail 17. The light beam 14 generated by the LED 12 (FIG. 1) is directed through an arcuate window 23 in the bucket-housing wall 21. Electrical wires 24 running to the reflective sensing unit 11 carry signals to and from the receipt-printing machine to energize the LED 12, and convey the signal from the eye 16 (FIG. 1), until such time as the paper supply is depleted.
Referring to FIGS. 3 through 5, three different bucket positions are illustrated for three different receipt-printing machine orientations associated with this invention.
FIG. 3 depicts a feed bucket 21 that is angled at 14° with respect to the horizontal plane, which is typical of a machine orientation mounted to the top of a desk. This position is given the designation "AA".
FIG. 4 depicts a bucket 21 that is at a substantially flat (0° ) angle with respect to the horizontal plane, which may also be characteristic of a desktop-mounted, receipt-printing machine. This position is given the designation "BB".
FIG. 5 depicts a bucket 21 that is at a substantially right angle (90° ) with respect to the horizontal plane, which is typical of a receipt-printing machine that is wall-mounted. This position is given the designation "CC".
Referring to FIG. 6, an enlarged view of the supply bucket 21 shown in FIGS. 3 through 5 is shown. The supply roll 15 and the reflective sensing unit 11 are illustrated in three respective, designated positions 15aa, 11aa (phantom view); 15bb, 11bb (solid view); and 15cc, 11cc (phantom view), all of which correspond to the different bucket 21 orientations AA, BB and CC (FIGS. 3 through 5).
The position supply roll 15aa, 15bb or 15cc within the bucket 21 moves in accord with the orientation of the printer in respective positions AA, BB or CC. Regardless of the orientation of the printer, the reflective sensing unit 11 may readily be adjusted to maintain a reliable, low-paper condition signal.
Referring now to FIG. 7, there is shown a flowchart of the steps of the software-implemented, "de-bounce" system that forms a part of the present invention. Two signals, Output Status and Debounce Count, are first initialized to "not-low" and "0", respectively, step 50. The Paper Low Input Signal is next read from the reflective photosensor 11 (FIGS. 1-6), step 52. The Paper Low Input Signal is tested for a state of "low", step 54. If the Paper Low Input Signal indicates that paper is not low (a normal condition, with sufficient paper in the printer), control is returned to initialization, step 50. If the Paper Low Input Signal indicates that paper is low, the Output Status level is checked, step 56. If the Output Status level already indicates that a low-paper condition is present, the system again checks for a "low" state, step 52. If the Output Status level does not indicate a low-paper condition, the Debounce Count signal is incremented, step 58. The Debounce Count is then compared with a predetermined number, step 60. In the preferred embodiment, a predetermined count of ten has been found to provide satisfactory results. If a Debounce Count of ten has not been reached, step 60, the system again checks for a low state, step 52. If a Debounce Count of ten has been reached, step 60, the low-paper Output Status signal is set to indicate paper low, step 62, and, once again, the system checks for a low state, step 52. This process continues until the paper roll is replaced and the paper input signal is no longer low, step 52, and the system is re-initialized, step 50.
Under normal operating conditions, the aforementioned method has been proven to provide reliable, low-paper indications. A flowchart of an alternate embodiment of the de-bounce method is shown in FIG. 8. This is a more robust embodiment, where the Debounce Count signal is both incremented and decremented in response to the Paper Low Input Signal and the low-paper Output Status. Two signals, Output Status and Debounce Count, are first initialized to "not-low" and "0", respectively, step 50. The Paper Low Input Signal is next read from the reflective photosensor 11 (FIGS. 1-6), step 52. The Paper Low Input Signal is tested for a low state, step 54. If the Paper Low Input Signal is not low (the normal condition, with sufficient paper in the printer), control is passed to decision step 64. The branch containing decision step 64 will be discussed in further detail hereinbelow. If the Paper Low Input Signal is low, step 54, the Debounce Count signal is compared with a predetermined number, step 60. If the Debounce Count is greater than ten, step 60, the Paper Low Input Signal is again read, step 52. If the Debounce Count signal is not greater than ten, step 60, the Debounce Count is incremented, step 58, and again compared with the predetermined number ten, step 60'. If the Debounce Count is less than or equal to ten, the Paper Low Input Signal is again read, step 52. If, however, the Debounce Count is greater than ten, step 60', the Output Status level is set to indicate a low-paper condition, step 62, and the control is again passed to step 52.
Returning to decision step 54, if the Paper Low Input Signal is high (not low), step 54, the Debounce Count is checked, step 64. If the debounce is equal to zero, the Paper Low Input Signal is again read, step 52. If the Debounce Count is not equal to zero, step 64, the Debounce Count is decremented, step 66, and is again compared to zero, step 64'. If the Debounce Count is not equal to zero, step 64', the Paper Low Input Signal is again checked, step 52. If the Debounce Count is equal to zero, step 64', the Output Status signal is set to indicate that paper is no longer low, step 68, and the Paper Low Input Signal is again read, step 52.
It will be obvious to those skilled in the art that although an optical, reflective, photosensor has been chosen for purposes of disclosure, the present invention could be implemented by using a photo-transmissive (i.e., see-through) sensing system, an ultrasonic sensing system (either reflective or see-through), a pneumatic sensing system, or any other suitable technology for accomplishing this paper-sensing function.
Since other modifications and changes varied to fit particular operating requirements and environments will be apparent to those skilled in the art, the invention is not considered limited to the examples chosen for purposes of disclosure, and covers all changes and modifications which do not constitute departures from the true spirit and scope of this invention.
Having thus described the invention, what is desired to be protected by Letters Patent is presented in the subsequently appended claims. | The present invention features a photosensing mechanism for a receipt-printing machine which senses a low condition of a paper supply roll housed within a bucket of the receipt-printing machine. The paper-supply roll has a "floating" characteristic; that is, no fixed rotational mounts align the roll within its feed bucket. The photosensing mechanism adjusts to different supply-roll positions within the feed bucket, the different positions of which result from different mounting orientations of the receipt-printing machine. | 1 |
This application is a continuation of application Ser. No. 742,850, filed Jun. 10, 1985 which was a continuation of application Ser. No. 554,319, filed Nov. 22, 1983, both now abandoned.
BACKGROUND OF THE INVENTION
The present invention relates to a thermal transfer color printer, and in particular, to a thermal transfer color printer for printing images on a record medium in the form of sheets of paper.
Thermal transfer color printers have been proposed in which colored ink is selectively transferred from a carrier sheet, such as an ink ribbon, to a recording medium (e.g., plain paper or the like) by applying thermal energy to localized areas on the carrier. For example, Japanese Published Patent Application No. 57-174276 discloses a printing system in which a multicolored ink ribbon having nearly the same width as the recording paper is used. Each color area of the ink ribbon is at least as large as the entire area of the picture to be printed and the different color areas are alternately and successively arranged along the length of the ink ribbon. A thermal printhead applies thermal energy to localized areas on the ink ribbon for transferring the colored ink onto the recording paper. In operation, the thermal printhead prints a color image by receiving signals for the various color components in succession. When the first color component signals are received, the corresponding color area of the ink ribbon is advanced by one picture length in synchronization with the advancement of the recording paper. The recording paper then is transported in the reverse or backward direction by one picture length while the ink ribbon is in position to print the next color area. The second color component signals then are received by the thermal printhead and the ink ribbon and recording paper are again advanced by one picture length. Depending on the number of color components, the recording paper is repeatedly transported backward for printing additional color components. The color components are superimposed in the same area of the recording paper to complete the printing of the color image.
Though the above thermal transfer color printer is effective in printing a color image, it has a significant disadvantage if long paper in the form of a roll must be utilized as the recording medium. As a result, color printing on separate sheets of plain paper is not possible.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide an improved thermal transfer color printer which is capable of printing color pictures on a record medium in the form of cut sheets of plain paper having a predetermined size.
It is another object of the present invention to provide an improved thermal transfer color printer having a simple and inexpensive construction and which is capable of reproducing multiple color pictures on separate sheets of paper with high quality and resolution.
According to the invention, a thermal color printer is provided with a paper cassette or container for storing a recording medium in the form of separate sheets of paper which are removed from the container one by one and transported toward a platen roller through an entry guide. The platen roller can be rotated clockwise and counter clockwise by a drive motor. A paper sheet removed from the paper container is transported by the platen roller and a first pinch roller or an entry pinch roller provided adjacent to the platen roller in a first direction along the surface of the platen roller. The paper sheet then passes between the platen roller and a second pinch roller or an exit pinch roller which is also provided adjacent to the platen roller at the opposite side from the first pinch roller. The thermal color printer is provided with an ink carrier sheet or ink ribbon having various transferable colored ink areas alternately and successively arranged along its length. Each of the colored ink areas has a width at least as wide as a color picture image to be printed. The colored ink ribbon is transported along the surface of the platen roller over the paper sheet in the same first direction as the paper sheet by a carrier drive mechanism. A thermal printhead is provided on the surface of the platen roller. The thermal printhead has a row of thermal elements, each of which may be energized to transfer a colored ink onto the paper sheet as the ink ribbon moves over the printhead. The printhead selectively contacts the ink ribbon and the paper sheet on the surface of the platen roller as the ink ribbon and paper sheet advance at the same rate along the surface of the platen roller. Electrical signals for a particular color component are supplied to the printhead to selectively energize the thermal elements so that they transfer a corresponding first colored ink onto the paper sheet as the ink ribbon and paper sheet are advanced in the first direction by one picture length. The platen roller also transports the paper sheet in a second direction opposite the first direction by a distance equal to one color length while the printhead is disengaged from the surface of the platen roller. Electrical signals for a second color component are supplied to the printhead to transfer a corresponding second colored ink onto the paper sheet while the paper sheet and the ink ribbon are transported in the first direction. The above printing cycle is repeated for each color component until all color components are printed. During each printing cycle, the paper sheet is moved forward by platen roller and the first pinch roller at the entrance side of the platen roller and backward by the platen roller and the second pinch roller at the exit side. As a result, color patterns for different colored inks are superimposed on the paper sheet to create a color image.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view showing a preferred embodiment of the thermal transfer color printer according to the present invention.
FIG. 2 is a perspective view of the upper side of the upper bracket taken from a direction shown by arrow A in FIG. 1.
FIG. 3 is a side sectional view showing a cassette for containing separate sheets of recording paper.
FIG. 4 is a perspective view of the lower side of the upper bracket taken from a direction shown by arrow C in FIG. 1.
FIG. 5 is a perspective view showing the lower bracket of FIG. 1.
FIG. 6 is a perspective view showing an example of the ink ribbon used in the present invention.
FIG. 7 is a perspective view schematically showing the ink ribbon transportation system according to the present invention.
FIG. 8 is a perspective view schematically showing a device for moving the thermal printhead up and down.
FIG. 9 is a schematic diagram showing the overall thermal transfer color printing system according to the invention.
FIG. 10 is a perspective view partly showing the platen roller and a pair of pinch rollers supported adjacent the platen roller to shift toward and away from the platen roller.
FIGS. 11-13 are schematic diagrams showing the operation of the thermal transfer color printer according to the present invention.
FIG. 14 is a timing diagram showing the timing of various signals for controlling the thermal printer according to the present invention.
FIG. 15 is a block diagram showing a control circuit for controlling the thermal printer according to the present invention.
FIGS. 16 and 17 are graphs showing the variations in tension forces F 1 , F o and F p when the length l of the ink ribbon varies.
FIG. 18 is a block diagram of a control circuit for controlling the ink ribbon take-up motor.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is a perspective view showing a preferred embodiment of the thermal transfer color printer according to the present invention. The printer consists of upper bracket 10 and lower bracket 12 which are pivotally connected at their rear ends by pivot shaft 14. Upper bracket 10 is usually placed in a horizontal position on lower bracket 12 and is locked to lower bracket 12 by lock 16. Slide handle 18, which projects from sliding plate 19, is slidably mounted on upper bracket 10 to engage grip shaft 20. Upper bracket 10 is unlocked from lower bracket 12 by gripping slide handle 18 and sliding it horizontally towards grip shaft 20, which simultaneously drives lock 16 in the horizontal direction via pivoting levers 17 to unlock upper bracket 10. Upper bracket 10 can be pivoted upward around pivot shaft 14 by lifting slide 18 and grip shaft 20.
A paper container or cassette 22 for containing recording paper 24 is mounted on the upper side of upper bracket 10. A paper tray 26 projects from upper bracket 10 for guiding and holding printed paper exiting from the printer. Recording paper 24 in paper cassette 22 is in the form of cut sheets of plain paper having a predetermined size, for example, A 4 size, etc.
FIG. 2 is a perspective view showing the upper side of upper bracket 10 taken from a direction shown by arrow A in FIG. 1. Cassette support plate 30 is provided between side walls 32 and 34. Support plate 30 is positioned so that front portion 36 is lower than rear portion 38. A pair of L-shaped arms 40 are rotatably mounted on support shaft 42 which is supported by side walls 32 and 34 above the front portion of support plate 30. Rotatable shaft 44 is rotatably supported by the upper tips of L-shaped arms 40. A pair of paper feed rollers 46 are mounted on rotatable shaft 44. Gear 48 on one end of rotatable shaft 44 meshes with smaller gear 50 on the inner side of wall 34. Paper cassette 22 pushes the lower tips of L-shaped arms 40 when it sets on supporting plate 30 as shown in FIG. 3. Thus, gear 48 meshes with smaller gear 50 to rotate paper feed rollers 46 which contact individual sheets of recording paper 24 in cassette 22.
Paper lifting plate 51 loaded with springs 53 is mounted on the bottom of paper cassette 22 as shown in FIG. 3. Lifting plate 51 constantly exerts an upward force on paper 24 so that individual sheets of paper are fed out from the cassette one by one by paper feed rollers 46. Projection 54 formed at the rear end of cassette 22 is retained by spring plate 56 having a bent portion which engages projection 54 of cassette 22. Spring plate 56 is disengaged from projection 54 by a pair of pivot arms 58 mounted on rotating shaft 60 supported by side walls 32 and 34. Rotating shaft 60 is rotated by knob 62 mounted on the middle portion of the shaft.
Turning again to FIG. 2, a pair of cassette lifting levers 64 (FIG. 2) extend through cassette support plate 30. Levers 64 normally force the bottom of cassette 22 upward by a spring as explained in further detail below. A pair of paper discharge rollers 66 are rotatably supported by side walls 32 and 34. The recording paper on which the color image is printed is discharged through the pair of discharge rollers 66 from inside the printer. A pair of support plates 68 are provided adjacent discharge rollers 66 for supporting paper tray 26 (FIG. 1) therebetween. Also, as shown in FIG. 2, a pair of fans 70 are provided at the rear end of upper bracket 10 for cooling the inside of the printer.
FIG. 4 is a perspective view of the lower side of upper bracket 10 taken from the direction shown by arrow C in FIG. 1. Cassette lifting levers 64 are mounted on a rotating shaft 70 below cassette support plate 30. Rotating shaft 70, which is supported by side walls 32 and 34, is driven by spring 72 provided on side wall 34. Spring 72 normally forces cassette lifting levers 64 to rotate so that the upper ends of the levers push the bottom of cassette 22 as shown in FIG. 3. Platen roller 74, which is rotatably supported between side walls 32 and 34 of upper bracket 10, is driven by main motor 76 through toothed timing belt 78 which engages sprocket 80 mounted on an axis of platen roller 74. A pair of pinch rollers, including first entry pinch roller 82 and second exit pinch roller 84, are provided on opposite sides of platen roller 74. These pinch rollers are positioned in contact with the platen roller so that they rotate when platen roller 74 rotates. Guide roller 86 for guiding the ink ribbon is provided in parallel with exit pinch roller 84. Guide plate 88 and guide roller 90 for guiding the recording paper are located higher than exit pinch roller 84. Flappers 92 are mounted on pivot axis 94 for guiding the recording paper from guide roller 90 to one of two different guide paths. A pair of bent guide plates 96 are provided to form one guide path for temporarily receiving the recording paper.
FIG. 5 is a perspective view showing lower bracket 12 according to the invention. A pair of brackets 100 stand upright on bottom plate 102 at the rear end of lower bracket 12 for supporting pivot shaft 14 which in turn supports upper bracket 10. Control circuit 104 for electrically controlling the printer is mounted at the rear end of the lower bracket. Adjacent to the control circuit unit, ink ribbon supply reel 106 is mounted for supplying colored ink ribbon 108 (shown by a dotted line). Reel 106 is rotatably supported by side walls 110 and 112. Guide roller 114 guides ink ribbon 108 supplied from reel 106; guide roller 114 is rotatably supported between side walls 110 and 112 of the lower bracket.
Color sensor unit 115 for detecting the color of the ink on ink ribbon 108 is provided as shown in FIG. 5. Color sensor unit 115 includes elements 115a and 115b as shown in FIG. 7. Elements 115a and 115b extend from side wall 112 and ribbon 108 passes between these elements. Thermal printhead 116 is located next to the sensor unit. The thermal printhead comprises metal plate 118 having a plurality of heat emitting fins on the undersurface and an array of thermal elements 120 such as resistors formed on the upper surface of the metal plate separated by an insulative layer (not shown). Thermal printhead 116 further comprises drive circuit 122 provided on the upper surface of metal plate 118.
A pair of rollers 124 and 126, one of which is a wrinkle removal roller and the other is a peeling roller respectively, are rotatably mounted on the upper surface of thermal printhead 116. These rollers are arranged in parallel on opposite sides of the array of thermal elements 120. The array of thermal elements 120 and rollers 124, 126 are positioned so that they are brought into contact with the lower surface of platen roller 74 in upper bracket 10 when the upper bracket is closed on the lower bracket. The rear end of thermal printhead 116 is supported on side walls 112 and 114 by pivot pins 128. The front end of the thermal printhead can be moved up and down by a solenoid (not shown) which is explained in further detail below.
Ink ribbon 108 passes through a pair of rollers 130 and 132 mounted on lower bracket 12 as shown in FIG. 5. Distance measuring device 133 is provided adjacent rollers 130 and 132. Device 133 measures the distance that ink ribbon 108 moves. The measuring device comprises disc 134 mounted on one end of lower roller 132 and rotation detector 136. Rotation detector 136 includes light source 136a which transmits light to light receiving device 136b through holes coaxially distributed on disc 134. As ink ribbon 108 passes through rollers 130 and 132, it is rewound on take-up reel 138, which is rotatably supported by side walls 110 and 112 and driven by motor 140.
FIG. 6 is a perspective view of an example of the ink ribbon used in the present invention. The ink ribbon has four colored inks coated thereon: yellow (Y), magenta (M), cyan (C) and black (B). Each different color area is arranged alternately and successively along the length of the ribbon. The area of each color is approximately the same as the area of the colored image or picture, for example, if the colored image is A 4 size then each colored area on the ink ribbon is A 4 size. The different colored inks are coated on base layers made of polyethylene terephthalate film or condenser paper of 3-12 μm thickness. The thickness of the ink layers is 2-4 μm, and the ink melting point is preferably 60°-80° C. The ink ribbon, as already explained, is supplied from reel 106 and advanced in the direction shown by arrow 150; the ink ribbon is taken up on reel 138.
The recording paper used in the present invention has a surface which the ink ribbon contacts. The surface smoothness of the surface of the recording paper which contacts the ink ribbon is preferably 300 seconds or more, while the smoothness of the opposite surface of the recording paper is preferably up to 150 seconds. The smoothness of the opposite surface, however, is varied depending on the smoothness of the paper feed rollers shown in FIGS. 2 and 3.
FIG. 7 is a perspective view schematically showing the ink ribbon transportation system according to the invention. Unused ink ribbon 108 is wound on supply reel 106 which includes a pair of reel holders 160 and 162. Each reel holder comprises disc flange 164 and shaft 166 coaxially mounted on flange 164. Shafts 166 are rotatably supported in side walls 110 and 112 shown in FIG. 5. Disc flange 164 of reel holder 160 is pushed against ink ribbon supply reel 106 by coil spring 168; coil spring 168 abuts against stopper 170 mounted on shaft 166. Thus, supply reel 106 is removably supported between the reel holders. Additionally, break device 172 is located on one end of supply reel 106 to provide a frictional force on shaft 166.
The ink ribbon transportation system also includes take-up reel 138. Take-up reel 138 is rotatably supported on one end by reel holder 174 which is substantially of the same construction as reel holder 162 in that it comprises disc flange 164, shaft 166, coil spring 168 and stopper 170. The opposite end of the take-up reel is supported by reel holder means 175 which transmits the rotational force of driving motor 176 to the take-up reel through a friction coupling mechanism. The friction coupling mechanism includes disc flange 178 having annular body 180 projecting therefrom; annular body 180 is loosely mounted on shaft 166 which is in turn driven by motor 176. The annular body of flange 178 is inserted into a bore of cylindrical take-up reel 138 to transmit the rotational force of motor 176 to take-up reel utilizing a key locking device (not shown). The friction coupling mechanism further includes friction disc 182 mounted on shaft 166 to transmit rotational force to flange 178. Friction disc 182 includes felt coat 184 on one end surface facing disc flange 178 and pressing plate 186 on the other end of disc 182. Plate 186 is mounted on shaft 166 so that the rotational force of driving motor 176 can be transmitted to disc flange 178 through pressing plate 186 and frictional disc 182. The above friction coupling mechanism transports the ink ribbon at a constant rate irrespective of changes in the diameter of the ink ribbon wound on the take-up reel. This mechanism and the operation thereof is explained in detail in U.S. patent application Ser. No. 466,046.
Color sensor unit 115 also is shown in greater detail in FIG. 7. One element 115a of color sensor unit 115 contains two or three light sources 190 each emitting different colored light, e.g., yellow, red or green. Light emitting diodes (LED) can be used as such light sources. The other element 115b of color sensor unit 115 contains two or three light receiving devices 200, such as phototransistors, to receive each different colored light emitted from the corresponding light source. The above color sensor unit uses the output signals of light receiving devices 200 to detect the color of the ink on ink ribbon 108 passing through elements 115a and 115b. A detailed explanation of the operation of the color sensor unit in detecting the color of the ink ribbon is given in the above-identified patent application.
FIG. 7 also shows distance measuring device 133 in greater detail. This device measures the distance ink ribbon 108 has traveled by measuring the movement of a pair of rollers 130 and 132. Disc 134 mounted on the axis of roller 132 rotates as ink ribbon 108 passes by the roller. Rotation detector 136 includes light source 136a and light receiving device 136b positioned on opposite sides of disc 134. Light emitted from light source 136a is received through holes 134a of disc 134. The angular distance that disc 134 travels is measured by counting the output pulse signals from light receiving means 136b of rotation detector 136.
FIG. 8 schematically shows a solenoid device for moving thermal printhead 116 up and down to selectively bring the printhead into contact with the platen roller in the upper bracket. A pair of solenoids 202 are mounted on the bottom of the lower bracket. Solenoids 202 are coupled to horizontal lever 204 which is pivotably supported at its center on axis 206 projecting from the bottom of the lower bracket. The horizontal lever is pulled counter clockwise by spring 208 to abut stopper 210. Vertical lever 212 is positioned under the front portion of thermal printhead 116. The center of the vertical lever is pivotably supported by axis 214 projecting from vertical plate 216 mounted on the bottom of the upper bracket. The lower end of vertical lever 212 is pulled counter clockwise by spring 218 to engage one end of horizontal lever 204 to thereby rotate the horizontal lever clockwise. The upper end of vertical lever 212 has a projection 220 which contacts the lower surface of metal plate 188 of the thermal printhead.
The operation of the solenoid device of FIG. 8 is as follows. When solenoids 202 are not energized, horizontal levers 204 are rotated to the limit position defined by stoppers 210. Thus, vertical levers 212 are rotated by the end portion of the horizontal levers and projections 220 are lowered causing the printhead to move downward by its own weight. In this state, a fixed distance of 1-2 mm is left between the upper surface of the thermal printhead and the platen roller. When solenoids 202 are energized, horizontal levers 204 rotate around axes 206 to release vertical levers 212 which rotate by action of springs 218. Projections 220 of the vertical levers then move the printhead in the upward direction so that the upper surface of the thermal printhead is brought into contact with the platen roller.
FIG. 9 is a schematic diagram showing the overall thermal color printing system according to the invention. A pair of paper guide plates 230 are positioned to receive recording paper 24 as it is fed from cassette 22 by paper feed rollers 46. Paper guide plates 230 guide the paper downward in the upper bracket (not shown). At the end of guide plates 230, a pair of first drive rollers 232 are rotatably supported in the upper bracket. Guide plate 234 and first flappers 236 are positioned in the upper bracket to guide recording paper 24 vertically downward to platen roller 74 and entry pinch roller 82.
First flappers 236 are pivotably mounted on pivot pin 238 which is supported in the upper bracket. The pivot pin is rotated by rotary solenoid 239 (FIG. 12) so that the flappers are selectively placed in one of two positions: in a first position, flappers 236 guide the recording paper downward and, in a second position, they push against the recording paper at their round tops. A pair of horizontal paper guide plates 242 are mounted in the upper bracket opposite first flappers 236. The front ends 244 and 246 of guide plates 242 extend upward and downward, respectively, to form part of a return paper guide together with guide plate 234 and first flappers 236. Guide plates 242 provide a return guide path for temporarily receiving paper 24. The entrance of guide plates 242 is located adjacent the round tops of first flappers 236 when these flappers are in their second position as shown by phantom lines 240. At the lower end of lower guide plate 242, optical paper sensor 248 is positioned to detect the recording paper. Sensor 248 includes light emitting and receiving elements placed on opposite sides of the paper path.
Platen roller 74 and a pair of pinch rollers 82, 84 are positioned below optical paper sensor 248. As recording paper 24 passes optical paper sensor 248 and enters the area between platen roller 74 and entry pinch roller 82, the entry pinch roller is pulled back from the platen roller by solenoids 250 mounted on opposite sides of the upper bracket, one side of which is shown in FIG. 1. When solenoid 250, which is coupled to one end of L-shaped arm 252, is energized, it turns arm 252 around pivot shaft 254 which extends across the upper bracket in parallel with entry pinch roller 82. The opposite end of arm 252 engages the shaft of pinch roller 82 to pull roller 82 away from the surface of the platen roller.
Entry pinch roller 82 and exit pinch roller 84 are normally pushed against the surface of platen roller 74 by springs 256 as shown in FIG. 10. Both pinch rollers 82 and 84 are received in horizontally elongated holes 258 on the side walls of the lower bracket so that they can move horizontally along the holes.
Returning to FIG. 9, a pair of vertical guide plates 260 are mounted above and adjacent exit pinch roller 84 and platen roller 74. A second optical paper sensor 262 is mounted on vertical guide plates 260. This sensor, which has substantially the same construction as first sensor 248, detects the passage of recording paper 24 between vertical guide plates 260.
A pair of second drive rollers 264 are provided above guide plates 260 for transporting the paper upward to second flappers 92. The second drive rollers are rotatably supported by the side walls of the upper bracket (not shown). Flappers 92 are pivoted on pivot pins 94 by solenoids 265 (FIG. 13) so that flappers 92 are selectively placed at two positions: in a first position, flappers 92 guide the paper to the left toward bent guide plates 96 and, in a second position (shown by phantom lines), they guide the paper to the right towards a pair of guide plates 266. Guide plates 266 guide the recording paper to exit tray 26 through discharge rollers 66.
First and second drive rollers 232 and 264 and discharge rollers 66 are all driven by common main motor 76. Main motor 76 drives main motor shaft 76a which, as shown in FIG. 1, drives toothed timing belt 268 to transmit rotation to sprocket wheel 270 mounted on second drive rollers 264. The rotation of sprocket wheel 270 is transmitted to shaft 272 of first drive rollers 232. Gear 274, which is mounted on shaft 272, is rotated to drive smaller gear 276 meshed with gear 274. Gear 276 drives discharge rollers 66.
Additionally, FIG. 9 shows the relationship among the above described mechanism for moving the recording paper, thermal printhead 116 and the ink ribbon transportation system. The thermal printhead was described in connection with FIGS. 5 and 8 and the ink ribbon transportation system was described in connection with FIGS. 6 and 7. As further shown in FIG. 9, cooling fan 277 is provided to cool thermal printhead 116.
The operation of the recording process of the thermal transfer color printer according to the invention will now be explained with reference to FIGS. 9, 11, 12, 13 and 14. FIG. 14 is a timing diagram showing the timing of electric signals supplied to various parts of the printer during the printing process.
When paper cassette 22 is in place and initial preparations for recording have been made, recording paper 24 is removed from cassette 22 one sheet at a time by paper feed rollers 46 which are driven by paper feed motor 52. Motor 52 is driven for a time period determined by pulse signal 280 of FIG. 14(a). Pulse signal 282 of FIG. 14(b) then activates main motor 76 and signal 284 of FIG. 14(c) is simultaneously applied to main motor 76 to indicate the direction of rotation. In this embodiment, a "High" level signal for signal 284 rotates motor 76 in a direction which moves the recording paper forward through first and second drive rollers 232 and 264 and platen roller 74. Thus, a "Low" level signal for signal 284 moves the recording paper in the backward direction. Recording paper 24 is guided by first guide plate 230 into the interior of the apparatus and eventually reaches first drive rollers 232, which are driven by main motor 76. The first drive rollers 232, being coated with rubber, grip and transport recording paper 24 in the forward direction.
As recording paper 24 advances, it reaches first flappers 236, which are set in their substantially vertical first position in response to solenoid 239. Solenoid 239 is controlled by pulse signal 286 of FIG. 14(d). As the recording paper 24 is transported vertically downward, the front edge of the recording paper is detected by first optical paper sensor 248. When light emitted from sensor 248 is cut off by paper 24, output signal 288 (FIG. 14(k)) of sensor 248 changes from "Low" to "High." Main motor 76 continues to rotate for a fixed time period t 1 (FIG. 14(b)) after first optical paper sensor 248 detects the front edge of the recording paper. During this time period, entry pinch roller 82 is in contact with platen roller 74 as shown in FIG. 11, since solenoid 250 is deenergized by "Low" level signal 290 of FIG. 14(e). Further, thermal printhead 116 is not in contact with platen roller 74, i.e., it is not in the "down" state as shown in FIG. 11, since "Low" level signal 292 of FIG. 14(f ) is supplied to solenoid 202 (FIG. 8).
The recording paper is forwarded through a space between the lower surface of platen roller 74 and the upper surface of ink ribbon 108 to a position where its front edge has gone slightly past exit pinch roller 84, at which time main motor 76 is stopped. At this moment, 37 High" level signal 294 of FIG. 14(e) is applied to solenoid 250 and entry pinch roller 82 is pulled away from platen roller 74 for a short time period defined by width of the "High" level signal. During this period of time, pulse signal 286 (FIG. 14(d)) falls to a "Low" level thereby causing solenoids 239 to turn first flappers 236 to their second position as shown in FIG. 12.
As shown in FIG. 12, first flappers 236 push recording paper 24 against the opening of the horizontal guide path formed by guide plates 242. At this time, the front edge of recording paper 24 is held by platen roller 74 and exit pinch roller 84 and the rear edge of recording paper 24 is held by first drive rollers 232. Therefore, pushing force of the first flappers against the recording paper at an intermediate point results in elimination of slack in the recording paper so that the recording paper is set tightly against the platen roller. This is a very important condition for thermal transfer color printing of high quality.
In the above state of the recording paper, solenoid 250 is deenergized by pulse signal 294 of FIG. 14(e), which changes to a "Low" level, thereby bringing entry pinch roller 82 into contact with platen roller 74. The thermal printing process now moves into the thermal transfer printing stage.
Thermal printhead 116 now is brought into its pressure application state, i.e., it is lifted upward, by applying pulse signal 296 of FIG. 14(f) to solenoid 202. The array of thermal heating elements 120 on the thermal printhead press ink ribbon 108 and recording paper 24 onto the surface of platen roller 74. Main motor 76 and motor 176, the latter of which controls movement of ink ribbon 108, are now actuated by pulse signals 298 of FIG. 14(b) and 300 of FIG. 14(g), respectively, for a predetermined period of time. During this predetermined period of time, one of the color component signals Y is supplied to thermal printhead 116 to selectively energize the thermal heating elements.
Color component signals Y, M, C and B of FIG. 14(j) can be produced by various known techniques. The color component signals of red, green and blue, the principal three colors of light which are generated by a color television camera, can be converted into the principal three painting colors Y, M and C by a color matrix circuit which is well known in the field of color televisions. Another way of obtaining the color component signals is by scanning an original color picture with a laser beam. The reflected laser beam is divided into color components by color filters. Each color component is then converted into an electric signal by a photosensor, such as a CCD device.
When color component signal Y is supplied to printhead 116, ink area Y on ink ribbon 108 is adjacent heating elements 120. FIG. 14(j) shows the timing relationship between the movement of each ink area of different color, as detected by color sensor unit 115 positioned at the rear of thermal printhead 116, and the color component signals. When printhead 116 heats the ink on ink ribbon 108, the ink is softened and transferred onto recording paper 24 in accordance with the image signal. Ink ribbon 108 then is separated from recording paper 24 by roller 126 mounted on printhead 116.
Recording paper 24 continues to move forward and is guided in an upward direction by guide plates 262. While thermal transfer continues, the front edge of the paper is detected by second optical paper sensor 262. Output signal 302 of sensor 262 is shown in FIG. 14(l). One function of this output signal is to detect when the paper is stuck inside the printer. As the recording paper advances toward second flappers 92, it is gripped by a pair of second drive rollers 264. Second flappers 92 are set in their first position as shown in FIG. 13 by solenoid 265, which is supplied with "Low" level signal 304 of FIG. 14(h). Thus, recording paper 24 enters the guide path defined by bent guide plates 96.
While the front edge of recording paper 24 is temporarily received in the guide path defined by bent guide plates 96, its rear end continues to be gripped by entry pinch roller 82 and exit pinch roller 84. Therefore, there is no risk of the recording paper coming out of engagement with the entry and exit pinch rollers on opposite sides of the platen roller.
After enough time has passed to complete the recording of the first color Y, main motor 76 is stopped and thermal printhead 116 is lowered in response to pulse signals 298 and 296 of FIGS. 14(b) and (f), respectively. Output signal 288 (FIG. 14(k)) of first paper sensor 248 now changes to a "Low" level since the rear end of the recording paper has passed the sensor. At this moment, signal 284 of FIG. 14(c) drops to a "Low" level which reverses the main motor.
Ink ribbon take-up motor 176 is also stopped when the main motor is stopped. However, motor 176 is immediately actuated again by short pulse signal 306 of FIG. 14(g). During the short period of time defined by the pulse width of signal 306, ink ribbon 108 moves forward until the front edge of the next colored ink area M (FIG. 6) comes over thermal heating elements 120 of thermal printhead 116 for the next printing cycle. Movement of ink ribbon 108 is also controlled by output pulse signal 308 of FIG. 14(i), which is generated by distance measuring device 133. The number of pulses output from distance measuring device 133 is proportional to the distance which ink ribbon 108 is advanced by take-up motor 176. When take-up motor 176 starts moving, simultaneously main motor 76 starts moving in its reverse direction. Platen roller 74 reverses rotation so that recording paper 24 moves backward. The speed of this backward movement of the recording paper preferably is faster than forward movement as described in further detail in U.S. patent application Ser. No. 466,046. During backward movement of recording paper 24, first flappers 236 are positioned in their second position so that the rear edge of the paper is temporarily received in the horizontal guide path defined by guide plates 242 as shown in FIG. 13. The front edge of recording paper 24 is again brought into a recording start position as mentioned above. When the recording paper is in this position, output signal 302 (FIG. 14(l)) of second paper sensor 262 drops to a "Low" level and output signal 288 (FIG. 14(k)) of first paper sensor 248 again rises to a "High" level. Main motor 76 then is de-energized by pulse signal 309 (FIG. 14(b)) and signal 284 (FIG. 14(c)) again goes "High" to begin another forward movement of the recording paper and the ink ribbon.
This completes the first step or cycle of the printing process, i.e., the printing of the first color component. The second step or cycle of the printing process, i.e., printing the second color component, is now ready. The same printing steps are repeated three times for superimposing printing images of other different colors, e.g., magenta, cyan and black, on the same recording paper.
In the last printing step or cycle for the black color component, at the moment the front edge of the recording paper is detected by second optical paper sensor 262, second flappers 92 are switched over to their second position shown by phantom lines in FIG. 9. Flappers 92 are controlled by pulse signals 310 and 312 of FIGS. 14(l) and (h). Recording paper 24 is forwarded along guide plates 266 while printing of the black color component is carried out. The recording paper exits the interior of the apparatus and is removed to paper tray 26 by discharge rollers 66. Pulse signal 312 for driving second flappers 92 then drops to a "Low" level to return flappers 92 to their first position. At the same time, pulse signal 314 for driving main motor 76 drops to "Low" to stop the main motor and complete all the steps for printing a color image on the recording paper.
FIG. 15 is a block diagram showing the electrical circuit for controlling the printer in the manner described above in connection with the timing diagram of FIG. 14. This circuit includes CPU 330, such as a microcomputer, for controlling the entire circuit. Bus line 332 transmits data signals to and from CPU 330. Read only memory (ROM) 334 is connected to bus line 330 for storing a program for controlling CPU 330. Pulse generator 336 is connected to CPU 330 to supply clock pulses thereto and power supply 338 is connected to bus line 332 through power interface 340 to provide power to the electrical circuit.
Amplifiers 340-350 amplify output signals provided by rotation detector 136, color sensors 115 for ink ribbon 108, first paper sensor 262 and second paper sensor 248. The output signals i, j, h and k (shown in FIG. 14) of these amplifiers are supplied to bus line 332 and CPU 330 through sensor interface unit 352.
Solenoid drive circuits 354-360 supply drive signals to solenoids 265 and 239 for flappers 92 and 236, solenoid 250 for shifting pinch roller 82 and solenoid 202 for moving printhead 116 up and down. Control signals h, d, e and f (shown in FIG. 14) are supplied to each solenoid drive circuit 354-360 from CPU 330 through bus line 332 and solenoid interface unit 362.
Motor drive circuits 364-368 drive ribbon take-up motor 176, main motor 76 and paper feed motor 52. Control signals g, c, b and a (shown in FIG. 14) are supplied to each drive circuit 364-368 from CPU 330 through bus line 332 and motor interface unit 370. A control signal also is supplied from CPU 330 to a known thermal printhead drive circuit 122 which drives thermal printhead 116.
Power supply 338 supplies three different voltages, e.g., 5, 24 and 9 volts, to its output lines 372-376. The first output voltage, 5 volts, is supplied to all the amplifiers, solenoid drive circuits, motor drive circuits and the thermal printhead drive circuit to drive TTL logic circuits included therein. The second output voltage, 24 volts, is supplied to all the solenoid drive circuits and motor drive circuits to drive the solenoids and motors. The third output voltage, 9 volts, is supplied to thermal printhead drive circuit 122 for selectively energizing the thermal or heating elements thereof.
CPU 330 is responsive to the program stored in ROM 334 to generate the control pulse signals shown in FIG. 14 and derive these control pulse signals from the output of pulse generator 336. The program controlled CPU controls the operation of all drive circuits at times corresponding to the timing diagram of FIG. 14 and it receives input signals from the sensors shown in FIG. 15 monitoring the operation of the printer. The CPU generally operates in response to the stored program in ROM 334 to control the overall operation of the printer in the manner described above in connection with FIGS. 9 and 11-14.
While multicolored recording is being carried out by the thermal transfer recording process described above, blurring due to inaccurate superimposing of different color images during the recording process must be prevented. In the printer of the present invention, the ink ribbon is transported in a first or forward direction by a drive mechanism including supply reel 106 coupled to break device 172 and take-up reel 138 driven by driving motor 176. This ink ribbon transportation system causes a certain amount of tension along the ink ribbon. This tension is great enough to provide a guide surface for guiding the recording paper along the surface of the platen roller.
The tension along the ink ribbon is represented as the difference between the forward tension force F 1 caused by the wind-up action of the take-up reel and the back tension force F 0 caused by the breaking action of the supply reel as shown in FIG. 16. It has been found by experiment that the values of these tension forces F 1 and F 0 are a function of the length l of the ink ribbon transmitted from the supply reel to the take-up reel as shown in FIG. 16. As shown therein, F 1 gradually decreases as length l increases, whereas F 0 , which is initially smaller than F 1 , gradually increases until it exceeds F 1 . This phenomenon takes place because the diameters of the ink ribbon wound on the supply reel and take-up reel change during transportation of the ink ribbon from the supply reel to the take-up reel, which results in changes in the torque force.
The tension forces F 1 and F 0 on the ink ribbon effect the rotation rate of the platen roller in such a way that if F 1 is larger than F 0 (F 1 >F 0 ), the rotation rate of the platen roller is increased, which then results in an unfavorable increase in the transportation of recording paper. On the other hand, if F 1 is smaller than F 0 (F 1 <F 0 ), the opposite result is achieved. The tension force F transmitted to the recording paper is expressed as follows:
F=F.sub.p +(F.sub.1 -F.sub.0) (1)
where F p is the tension force exerted by the platen roller on the recording paper. This force F, which is plotted in FIG. 17, gradually decreases as more of the ink ribbon is used. Thus, the rate of transportation of the recording paper in the first or forward direction gradually decreases as the ink ribbon is used, while the rate of transportation of the recording paper in the second or reverse direction is not affected by the ink ribbon since the thermal printhead is in the down or disengaged state.
The above differences in the transportation rate of the recording paper causes an undesirable displacement of the dots of different color to be superimposed on the recording paper from the ink ribbon. This undesirable effect is resolved in the present invention by a control system for the drive motor for the platen roller as shown in FIG. 18.
The control system of FIG. 18 includes pulse generator 400 which generates pulses supplied to advance pulse counter 402 and reverse pulse counter 404, both of which are ultimately controlled by operation of CPU 416. Counters 402 and 404 generate a predetermined number of pulses at their output terminals. The output pulses of counters 402 and 404 are selectively switched by switching circuit 406 and supplied to drive circuit 408. Drive circuit 408 drives take-up motor 176, which is a pulse motor for driving the take-up reel.
The mechanism for determining the number of pulses generated by reverse pulse counter 404 will now be described. The number of sheets of recording paper printed by the thermal printer for a particular roll of ink ribbon is counted by paper number counter 416. This paper number counter may be responsive to signals from the first and second optical paper sensors 248 and 262 (FIG. 9) or it may be responsive to the CPU program which effects the overall movement of recording paper in the printer. Paper number counter 416 operates in conjunction with memory 412 to generate a correction value I which is directly related to the number of printed sheets of recording paper. For example, correction value I may be a positive or a negative value which changes for each 5 to 10 printed sheets of recording paper. This correction value I is added to a predetermined number M in addition circuit 414. The predetermined number M, which is stored in memory 410, corresponds to the number of output pulses generated by reverse pulse counter 404 in the previous printing cycle. The sum of correction value I and predetermined number M results in a new predetermined number M' which is supplied to reverse pulse counter 404 by addition circuit 414. Reverse counter 404 then supplies M' reverse pulses to switching circuit 406.
As shown in FIG. 17, when the number of printed sheets of paper is small, the force acting on the recording paper is greater than force F p so that the recording paper advances too far. Therefore, the correction value I is made positive (I>0), which causes an increase in the number of reverse pulses to thereby increase the amount of recording paper returned. On the other hand, when the number of printed sheets of recording paper is large, the used length of the ink ribbon increases. As shown in FIG. 16, the force acting on the recording paper then is smaller than the force F p so that the recording paper does not advance far enough. Therefore, the correction value I is now made negative (I<0), which causes a decrease in the number of reverse pulses to thereby decrease the amount of recording paper returned.
Although an illustrative embodiment of the present invention has been described in detail with reference to the accompanying drawings, it is to be understood that the invention is not limited to the precise embodiment described herein. Various changes and modifications may be effected in the above described embodiment without departing from the scope or spirit of the present invention. | A thermal transfer color printer for printing color images on individual sheets of paper. One sheet of paper at a time is removed from a stack of paper stored in a cassette and this sheet is transported by a reversible platen roller in a first or forward direction at a first predetermined rate. While the sheet of paper is gripped between the reversible platen roller and one or more pinch rollers, slack is removed by a slack removing device. A multicolored ink ribbon with successively arranged color segments also is transported in the first direction at the same predetermined rate. A thermal printhead presses against the reversible platen roller to press the ink ribbon and sheet of paper together as they move in the first direction. Energization of the thermal elements on the thermal printhead by color component signals corresponding to the current color of the ink ribbon causes the particular current color to be thermally and selectively transferred to the sheet of paper. The thermal printhead then disengages the platen roller and the sheet of paper is transported in a set distance in a second direction opposite the first direction, and at a second predetermined rate, in order to repeat the process of thermally transferring other colors to the sheet of paper. During the back and forth movement of the sheet of paper, the reversible platen roller and the pinch rollers continuously grip the sheet of paper in order to precisely control the position of the sheet of paper to thereby avoid distortion. A complete color image is formed on the sheet of paper by superimposing the multiple colors of the ink ribbon as the sheet of paper and the different colors of the ink ribbon repeatedly move past the selectively energized thermal elements of the thermal printhead. | 8 |
FIELD OF THE INVENTION
This invention relates to an electromagnetic actuator for door units and the like, particularly for up-and-over doors.
BACKGROUND OF THE INVENTION
Devices for opening and closing up-and-over doors are known. One of these comprises a geared motor fitted to the up-and-over door and provided with a transversely extending exit shaft connected by articulated vertical arms to couplings rigid with the uprights of the door frame. Rotation of the geared motor causes the articulated arms to rotate about the corresponding frame couplings, with consequent opening and closure of the up-and-over door.
A drawback of this known device is its difficulty of installation, which requires several operations on the up-and-over door for fitting it with external members such as the supports for the geared motor, the support bushes for the transverse shaft, the articulated arms and the relative couplings on the door frame.
A further drawback is that these members increase the weight of the entire door and therefore require adjustment of the counter-weights or the compensation springs to counterbalance said weight.
A further drawback is that the transverse shaft does not allow a usual inwardly opening small service to be applied to the up-and over door.
A further drawback is that up-and-over doors of different width require transverse shafts of corresponding length, with the evident impossibility of constructing standardized operating devices applicable to any up-and-over door.
To obviate these drawbacks an up-and-over door operating device has been proposed comprising a rail to be fixed to the room ceiling to the up-and-over door and able to guide a trolley connected to the door upper cross-member by an articulated bar. The trolley is driven by a belt or chain extending between two sprockets, one of which is driven, so that rotating the motor in one or the other direction causes the trolley to travel along its guide and hence open and close the up-and-over door.
The drawback of this arrangement is a certain constructional complexity due to the large number of components (articulated bar, trolley, trolley guide, chain, chain tensioner, geared motor) and hence the high cost of the device plus the considerable labor involved in its installation.
A further drawback is that the large number of moving parts, each of which is potentially subject to breakdowns, means that its operation is not particularly reliable.
As an alternative to the endless chain it has also been proposed to move the trolley along the guide by a threaded rod driven by a geared motor and engaging a threaded bush rigid with the trolley. In this manner the number of components and hence the installation complexity are reduced while at the same time increasing their reliability of operation, even if in practice the cost of the device plus its installation is not substantially different.
DISCUSSION OF THE PRIOR ART
DE-A-3501454 discloses an electromagnetic actuator for door units and the like comprising a tubular guide comprising two parallel side-by-side rectilinear portions, a flexible rack housed partly within one rectilinear portion of the tubular guide and partly within the other such that it can undergo axial sliding, a geared motor unit provided with a gearwheel engaging the flexible rack via an aperture provided in one of the two rectilinear portions of the tubular guide, one hanger fixed to said flexible rack, and members for mechanically connecting the hanger appendix to the door unit or the like.
SUMMARY OF THE INVENTION
An object of the invention is to provide a device of the above type which is of low cost, easy and quick installation, reliable operation and universal use.
This and further objects which will be apparent from the following description are attained according to the invention by an electromagnetic actuator for door units and the like, particularly for up-and-over doors, comprising:
a tubular guide comprising at least two parallel side-by-side rectilinear portions,
a flexible rack housed partly within one rectilinear portion of the guide and partly within the other such that it can undergo axial sliding,
a geared motor unit provided with a gearwheel engaging the flexible rack via an aperture provided in at least one of the two rectilinear portions of the tubular guide,
at least one hanger fixed to said flexible rack, and
members for mechanically connecting the hanger appendix to the door unit or the like to moved,
wherein:
the flexible rack consists of a metal wire spirally wound about a flexible core,
the hanger is emerging via an appendix through a continuous longitudinal slot provided in at least one of the two rectilinear portions,
the gearwheel of the geared motor unit simultaneously engages two points of the flexible rack within the two rectilinear tubular guide portions.
BRIEF DESCRIPTION OF THE DRAWINGS
Some preferred embodiments of the present invention are described in detail hereinafter with reference to the accompanying drawings, in which:
FIG. 1 is a schematic side view of an electromagnetic actuator according to the invention applied to an up-and-over door;
FIG. 2 is an exploded perspective view thereof;
FIG. 3 is an enlarged horizontal view thereof on the line. III--III of FIG. 1;
FIG. 4 is a cross-section therethrough on the line IV--IV of FIG. 3;
FIG. 5 is a longitudinal section therethrough on the line V--V of FIG. 3;
FIG. 6 is a longitudinal section therethrough on the line VI--VI of FIG. 5; and;
FIG. 7 shows a further partial embodiment thereof in the same view as FIG. 3;
DESCRIPTION OF THE PREFERRED EMBODIMENTS
As can be seen from the figures, the electromagnetic actuator according to the invention comprises an electric motor 2, preferably powered by direct current via a control unit 4 and having a worm 6 keyed onto its exit shaft 8. The worm 6 engages a helical ring gear 10, on the shaft 12 of which there is keyed a gearwheel 14 engaging a flexible rack 16, consisting of a steel wire spirally wound at constant pitch about a flexible core in the form of a metal cord.
The flexible rack 16 is housed within a tubular guide 18 fixed to the Ceiling 20 and comprising two rectilinear portions 22, 24 positioned perpendicular to the upper cross-member of the up-and-over door 26. Each rectilinear portions 22, 24 comprises a lateral aperture 28, through which the gearwheel 19 engages the flexible rack 16. The portion 22 also comprises a continuous longitudinal slot 30 along which there can slide the projecting arm 32 of a hanger 34 which is fixed to one end of the flexible rack 16 and is connected to the central part of the upper cross-member of the up-and-over door 26 by an articulated arm 36.
The two rectilinear portions 22,24 of the tubular guide 18, advantageously consist of two parallel longitudinal cavities of a single section bar formed for example of extruded aluminium, as is apparent from FIG. 5. Specifically, this extruded section bar comprises a central longitudinal cavity, forming the tubular guide portion 22, and two cavities flanking the sides of this latter, one of which forms the other rectilinear portion 24 and the third 38 forms a service cavity for the passage of electric cables. In a position below the three cavities 22, 24 and 38 there is provided a further cavity 50 for guiding a slide 42 rigid with the hanger 34 fixed to the flexible rack 16. The slide 42, the cross-section of which is overall complementary to the cross-section of the cavity 40, in reality comprises a block with two inclined surfaces, between which there is a seat 44 in which there snap-engages elastically, by the effect of a spring 46, a pin 48 provided in a second slide 50 slidable along a longitudinal cavity 52 formed in the same section bar in a position below the longitudinal cavity 40. The pin 48, which as stated is elastically maintained in engagement with the seat 44 provided in the slide 42 by means of a spring 46, can be operated from the outside by means of its appendix 54, which is provided with a hooking ring. The slide 50 is provided with a lug 56 for connecting that end of the articulated bar 36 not fixed to the up-and-over door 26.
As this embodiment of the actuator according to the invention makes continuity of the tubular guide 18 essential, the two rectilinear portions 22, 24 must be connected together at the end distant from the up-and-over door 26 by a rigid tubular connection element within which the flexible rack 16 can slide and be guided.
For installing the actuator according to the invention the procedure is as follows: if the tubular guide 18 is in the form of pieces of section bar, these pieces are firstly joined together to facilitate packaging and transport. This is easily accomplished because each piece is provided with two longitudinal cavities 58 into which blocks or plugs 60 can be inserted, to then be fixed by screws to the two pieces of section bar to be connected together.
A bracket 62 for securing the front end of the tubular guide 18 is then fixed to the lintel 61 upperly bounding the space within which the up-and-over door is applied, and a further bracket 64 for holding the box 66 housing the geared motor unit 2,6,8,10 the control unit 4 and a possible emergency electrical battery 67 is fixed to the ceiling.
The actuator according to the invention, comprising the tubular guide 18 and equipped with the box 66, is then fixed to the two brackets 62 and 64, and the articulated bar 36 is fixed at one end to a bracket 68 previously fixed to the up-and-over door 26 and at its other end to the lug 56 on the slide 50. If during installation it is found that the tubular guide 18 is too long, it can be shortened to the required length very easily by simply cutting off a piece of the section bar and a corresponding piece of the flexible rack 16.
During operation the rotation of the electric motor 2 causes the gearwheel 14 to rotate, resulting in axial sliding of the flexible rack 16 along the tubular guide from one rectilinear portion 22,24 to the other. As the slide 42 is applied via the hanger 34 to the flexible rack 16 and this slide is fixed to the slide 50 which is connected to the up-and-over door 26, it is apparent that rotating the electric motor 2 in one or the other direction causes the up-and-over door 26 to open and close. Traditional travel limiting systems, consisting for example of microswitches applied to the tubular guide 18 or forming part of the operational logic of the control unit 4, enable the electric motor to be operated only between the open and closed positions of the up-and-over door. If the electric power should fail, it is necessary merely to pull on the pin 48 in order to release the slide 50 from the slide 42 fixed to the flexible rack, and then manually move said slide 50 along the corresponding guide 52. To again mutually engage the two slides 50 and 42 it is sufficient to move the slide 50 towards the slide 42 until, after sliding along one of its inclined surfaces, the pin 48 snap-engages securely in the seat 44 provided between them.
It is apparent from the aforegoing that the electromagnetic actuator according to the invention is advantageous composed of and can be equipped with a very small number of part, in order to be of very low cost, quick to be installed and is of reliable operation.
With regard to the small number of parts, these consist substantially of a plate on which the control unit 4, the geared motor unit 2,6,8,10 and possibly the electric battery 67 for emergency operation are mounted, the tubular guide 18 and the bar 36 for connection to the up-and-over door 26. The small number of parts obviously results in a device of low cost and of considerable operational reliability.
With regard to quick installation, it is sufficient firstly to assemble the actuator on the ground in the already described form, then fix the bracket 62 to the lintel 61, then fix the end of the device guide 18 to said bracket 62, and then fix the device to the ceiling 20 by the bracket 64. Finally, after applying the bracket 68 to the up-and-over door 26 the articulated bar 36 is mounted between said bracked 68 and the slide 50 of the actuator. This is all achieved by simple operations which can be effected independently of each other, without risk of error and with the certainty of being able to adapt the device to up-and-over doors practically of any size.
According to the invention the flexible rack 18 is engaged by the gearwheel 14 in both the rectilinear portions 22, 24 of the tubular guide 18, which allows as an embodiment of the invention the loop formed by the flexible rack 18 to be unguided (see FIG. 3).
In this case not only is friction practically eliminated along the loop of the flexible rack, but in addition the actuator construction is considerably more simple.
In addition, from the operational viewpont this embodiment is particularly advantageous for operating with identical force two elements slidable in opposite directions.
This makes the actuator of the invention suitable for use in operating oppositely sliding doors, curtains or the like. In this case both the rectilinear portions 22,24 of the tubular guide 18 must be provided with a continuous longitudinal slot, and a hanger 34 must be fixed to the flexible rack 16 at each of said rectilinear portions 22,24. If these two rectilinear portions form part of single section bar, the section bar should be provided with separate longitudinal cavities 40 for two separate slides connected to the two hangers.
It is also possible (see FIG. 7) that the portion of the tubular guide 18 connecting the two rectilinear portions 22, 24 together is replaced by a plurality of idle rollers 70 arranged to cooperate with an idle guide pulley 72 so that the flexible rack 18 forms the loop connecting together the parts slidable within said rectilinear portions 22, 24.
Although this embodiment requires the rollers and guide pulley, it eliminates the need for a continuous tubular guide between the two straight portions 22 and 24, and hence simplifies the formation of said tubular guide 18 while at the same time reducing friction, which is inevitably present along the loop formed by said flexible rack. | An electromagnetic actuator for door units and the like, particularly for up-and-over doors, which includes a tubular guide having at least two side-by-side rectilinear portions, a flexible rack housed partly within one rectilinear portion of the guide and partly within the other, such that it can undergo axial sliding, a geared motor unit provided with a gearwheel engaging the flexible rack via an aperture, provided in at least one of the two rectilinear portions of the tubular guide, one hanger fixed to the flexible rack, and members for mechanically connecting the hanger appendix to the door unit or the like to be moved. | 4 |
FIELD OF THE INVENTION
[0001] The present invention relates generally to a smoke exhauster, and more particularly to a smoke exhauster housing suitable for mounting at a wall corner.
BACKGROUND OF THE INVENTION
[0002] The smoke exhauster is generally rectangular in shape and is mounted over a gas, electric, or induction range for removing the kitchen smoke such that the back of the smoke exhauster is fastened to the kitchen wall. The smoke is apt to escape from the spaces located at the left and the right sides between the range and the smoke exhauster. As a result, the interior designers make an effort to solve such a problem as described above by mounting the smoke exhauster and the cooker at the wall corner of the kitchen, so as to prevent the escape of the cooking smoke by two wall surfaces of the wall corner. The conventional gas stove is generally rectangular in shape. As shown in FIG. 1, the gas cooker and the smoke exhauster 91 are mounted at the kitchen corner such that their back sides and one of the left and the right sides are rested against the two wall surfaces which meet at right angle. The kitchen sink 92 extends along the wall corner to have an L shape. The user U must stand at the turning corner of the sink 92 to do the cooking. In light of the cooker being located at an inner corner of the sink 92 , the user U, the cooker, and the smoke exhauster are located in an aslant relationship, thereby resulting in a great deal of inconvenience to the user for operating the control panel. In order to provide a remedy, a design change is made by the interior designer such that the gas range and the smoke exhauster 93 are located slantingly at the kitchen corner, as shown in FIG. 2. The back corners of the gas range and the smoke exhauster 93 are rested against the two wall surfaces which meet at right angle, thereby resulting in a triangular space between the back sides of the gas range and the smoke exhauster and the walls. As a result, the kitchen sink and the overhead cabinet must be widened. The modern kitchen sink and the modern overhead cabinet are of a modular design such that they have a fixed size. For example, the sink has a depth of 60 cm, whereas the overhead cabinet has a depth of 37 cm. In order to coordinate the design that the gas range and the smoke exhauster are mounted slantingly at the kitchen corner, the depth of the sink and the depth of the cabinet must be increased at an additional cost. In addition, the sink and the cabinet would take up additional space in the kitchen.
SUMMARY OF THE INVENTION
[0003] The primary objective of the present invention is to provide a smoke exhauster with a housing which is designed to facilitate the mounting of the smoke exhauster at a kitchen corner without compromising the smoke exhausting efficiency of the smoke exhauster, and without a coordinating effort to redesign the kitchen sink or overhead cabinet.
[0004] The smoker exhauster housing of the present invention is provided in the back side with a left wall contact surface and a right wall contact surface. The smoker exhauster is mounted at a kitchen wall corner such that the two wall contact surfaces of the back side of the housing of the smoke exhauster are rested against the two wall surfaces of the kitchen corner.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] [0005]FIG. 1 shows a schematic view of a prior art smoke exhauster which is mounted at the corner of a kitchen.
[0006] [0006]FIG. 2 shows a schematic view of a prior art smoke exhauster which is mounted at the corner of a kitchen in another manner.
[0007] [0007]FIG. 3 shows an angle of elevation perspective view of a first preferred embodiment of the present invention.
[0008] [0008]FIG. 4 shows a top view of the first preferred embodiment of the present invention.
[0009] [0009]FIG. 5 shows a schematic view of the first preferred embodiment of the present invention in use.
[0010] [0010]FIG. 6 shows a top side shematic view of the first preferred embodiment of the present invention in use.
[0011] [0011]FIG. 7 shows an angle of elevation perspective view of a second preferred embodiment of the present invention.
[0012] [0012]FIG. 8 shows a top view of the second preferred embodiment of the present invention.
[0013] [0013]FIG. 9 shows a schematic view of the second preferred embodiment of the present invention in use.
[0014] [0014]FIG. 10 shows a top side schematic view of the second preferred embodiment of the present invention in use.
[0015] [0015]FIG. 11 shows a sectional view of the joining relationship of the smoker exhauster of the second preferred embodiment of the present invention and an overhead cabinet.
[0016] [0016]FIG. 12 shows a perspective view of a third preferred embodiment of the present invention.
[0017] [0017]FIG. 13 shows a perspective view of a fourth preferred embodiment of the present invention.
[0018] [0018]FIG. 14 shows a perspective view of a fifth preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0019] As shown in FIGS. 3 and 4, a smoke exhauster housing 10 of the first preferred embodiment is provided in the interior with a bellows and a smoke exhausting duct, which are not the subject matters of the present invention. The housing 10 has a sectoral profile, a left wall contact surface 11 , a right wall contact surface 12 , an arcuate front side 13 , and a top 14 . The left wall contact surface 11 and the right wall contact surface 12 are rectangular in shape and are joined together at the rear longitudinal sides thereof at about 90 degrees. The two opposite side edges of the front side 13 are joined with the outer side edges of the left wall contact surface 11 and the right wall contact surface 12 . As a result, the wall contact surfaces 11 and 12 are joined with the front side 13 to form a cylindrical body. The front side 13 is provided at the bottom of the front thereof with a switch 20 for controlling a motor mounted in the bellows and a lamp (not shown in the drawings).
[0020] As shown in FIGS. 5 and 6, the housing 10 of a smoke exhauster 30 is mounted in a kitchen comprising an L-shaped kitchen sink 42 , a gas range 44 located on the corner of the sink 42 , two overhead cabinet sets 46 , and a space located over the range 44 for mounting the smoke exhauster 30 between the two overhead cabinet sets 46 such that the left wall contact surface 11 and the right wall contact surface 12 of the housing 10 are securely held to the two wall surfaces forming a right angle, and that the front side 13 faces the kitchen center, and further that the left and the right side are rested against the inner sides of the cabinet sets 46 , and further that the upper and the lower end edges are flush with the overhead cabinets 46 .
[0021] The user stands at the corner of the sink 42 such that the user faces the range 44 and the smoke exhauster 30 . The cooking fumes are prevented by the walls from spreading throughout the kitchen or even to other rooms. The user can easily maneuver the switch 20 . The housing 10 is so shaped to fit into the corner without forming a triangular gap of the prior art. In addition, the front side of the exhauster 30 is not overextended so as to coordinate with the existing sink and cabinets. In short, the housing 10 of the present invention is so designed to fit beautifully with the kitchen corner without obstructing the arrangement of the cabinets.
[0022] As shown in FIGS. 7 and 8, a housing 50 of the second preferred embodiment of the present invention has a pentagonal profile, a left wall contact surface 51 , a right wall contact surface 52 , a left side 53 facing the left front, a right side 54 facing the right front, and a front side 55 facing the front. They are all rectangular surfaces, with the longitudinal side edges of two adjoining surfaces being joined together. They are joined with a pentagonal top 56 to form a pentagonal housing such that a right angle is formed between the left wall contact surface 51 and the right wall contact surface 52 , and that a right angle is formed between the left side 53 and the left wall contact surface 51 , and further that a right angle is formed between the right side 54 and the right wall contact surface 52 . The housing 50 is therefore fitted well with the corner of right angle and the rectangular overhead cabinets. The foregoing angles can be modified to adapt to a specific corner or cabinet design. The left side 53 , the front side 55 and the right side 54 are provided in the bottom edge thereof with a protruded edge 57 extending along an edge. The protruded edge 57 is provided in the underside with a switch 64 corresponding in location to the front side 55 .
[0023] As shown in FIGS. 9 and 10, the housing 50 of the smoke exhauster 70 is disposed between the two cabinet sets 46 ′ such that the left wall contact surface 51 and the right wall contact surface 52 are rested against the corner walls, and that the left side 53 and the right side 54 are in contact with the inner sides of the cabinet sets 46 ′. The smoke exhauster 70 is secured to the right angle junction of the two cabinet sets' 46 ′ such that only the front side 55 of the housing 50 is exposed to face the user, and that the protruded edges 57 come in contact with the side edge of the undersides of the cabinet sets 46 ′, as shown in FIG. 11, so as to seal off the gap between the housing 50 and the cabinet sets 46 ′.
[0024] As shown in FIG. 12, the planar front side 55 of the housing 50 described above is changed to have an arcuate surface. The arcuate front side 55 ′ of the housing 50 ′ is extended between the two cabinet sets to enhance the esthetic effect and to enlarge the volume of the housing.
[0025] The present invention is provided in the back side with a left wall contact surface and a right wall contact surface, which come in contact with the corner walls. The front side of the housing is of any geometric form. In addition, the left wall contact surface and the right wall contact surface of the back side of the housing of the present invention are not directly connected, as shown in FIG. 13 in which a housing 80 is shown to have a hexagonal profile, and a back side 81 connected with a left wall contact surface 82 and a right wall contact surface 83 . The left wall contact surface 82 and the right wall contact surface 83 are in contact with two walls of the corner such that a triangular space is formed at the innermost angle and is covered with a cover plate. As shown in FIG. 14, a housing 85 is a hybrid of those of FIGS. 7 and 13 and is provided with a pentagonal bottom and a hexagonal top. | A smoke exhauster comprises a housing with a back side which has a left wall contact surface and a right wall contact surface for making contact with two wall surfaces of a corner, thereby enabling the smoke exhauster to be mounted in the corner to exhaust the fumes and to facilitate the user to stand in front of the smoke exhauster to cook, without having to modify the kitchen furniture to coordinate with the smoke exhauster. The housing of the smoke exhauster is economical and capable of keeping the beauty and the function of kitchen. | 5 |
This application claims priority to U.S. Provisional Application Ser. No. 61/382,655 filed Sep. 14, 2011. The entirety of this application is hereby incorporated herein by reference in its entirety.
BACKGROUND
Anyone who ever saw a cowboy try to catch a cow using a rope knows that fetching an individual farm animal was always one of the toughest jobs on the farm. Approaching an individual farm animal is needed for various reasons; breeding and veterinary treatments are the most common ones. As the number of animals living on a farm increases, more data is collected on individual animals. Needs to approach or fetch specific animals are growing. Therefore, a reliable and cost-efficient solution to the problem of locating a specific animal is needed in the art.
In many prior disclosures, a location of animals is provided by an earth-orbiting satellite system. Such a system requires high power consumption from the device attached to the animal during communication and also requires line of sight between the animal and the satellites.
Other disclosures based on absolute pinpoint of an animal's location in a predefined coordinate system requires an expensive pre-installed array of antennas in the farm. The power consumption of such devices attached to the animal during communication is high because the device must transmit data for periods of minutes in order to enable accurate tracking.
Prior disclosures using RFID passive tags have been attached to the animal's ear or inserted into the stomach. Such devices do not contain a battery and theoretically have an endless lifespan. Such devices can be detected from only a very short range, such as, less than 1 m and can only find an animal confined to a very narrow space or passage.
A farmer or dairyman needs a system that can find an animal moving freely in a large confined area from a large distance of tens or even hundreds of meters. A transmitting device attached to the cow is an obvious choice in order to be practical and cost efficient. Such a device must have a very long life span because attaching the device to an animal is a very time consuming and tedious job.
What is currently needed in the art is a system and apparatus for identifying an individual animal in a group of animals in a paddock or pen by use of a device that consumes very low power. Such a device offers the advantage of being able to operate continuously for years using a small battery and thus requiring little or minimal battery replacement.
BRIEF DESCRIPTION
In accordance with one aspect of the present exemplary embodiment, the present application is a series of RFID transponders and receiving devices for tracking barnyard animals. The system involves electronic tags attached to the bodies of livestock. The signals are picked up by a receiver attached to a stationary platform, or located in a vehicle, or in a portable hand held receiver device. The information transmitted can be used to locate a specific animal or can be used to monitor the status and condition of the animal. The device contains several modes which minimize power consumption and maximize power supply lifetime.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an illustration of the signal path of the device.
FIG. 2 is an illustration of the interconnected modes and phases.
FIG. 3 is a flow chart of the method of use.
FIG. 4 is flowchart of the method of using the Handheld antenna based device.
DETAILED DESCRIPTION
FIG. 1 illustrates the concept presented in the current application 100 . One object of the present invention to provide a novel, low power consuming device for attachment to a farm animal 140 , 142 , 144 which may be able to receive and transmit signals 115 , 122 , 124 , 135 to and from remote receivers and/or transmitters. While the present application is directed toward farm animals such as but not limited to cows, bulls, steers, cattle, horses, goats, pigs, sheep, llamas, alpacas, chickens, hens, roosters, turkeys and any other birds, the present application may easily be applied to zoo animals such as elephants, rhinos, giraffes, or animals residing in the wild such as tigers, lions and bears.
One embodiment would include at least one mobile handheld approaching unit 120 . Another embodiment would contain at least one stationary 110 receiving and/or transmitting system. A further embodiment would have the receiver/transmitter mounted in a vehicle 130 . The device would be employed to approach an individual animal in a shed, a pen, or a paddock, either standing alone or staying with a group of animals in an economical and efficient way.
An Animal Receive/Transmit Unit or simply ARTU, comprises a mobile tag mounted or attached to an animal to receive/transmit data. The ARTU must be lightweight, small and consume little electrical power to limit the time consuming operation of recharging or replacing a battery. Replacement of a battery also limits the reliability of the ARTU because of risk of sealing damage or improper handling. This is exacerbated when battery charging is done in a farm or a dairy environment. An object of the present disclosure is to provide the ARTU with very low average power consumption, combined with responsiveness to the FLS and optionally the CBS which is simple, reliable and responsive to a fast approaching animal.
A Coarse Base Station or simply CBS is a stationary unit, mounted in the farm, diary, open yard, stable or any other area where the animal is expected to stay or pass through. The device may receive/transmit data from/to the ARTU, as well as registering said specific ARTU data such as identity, time, and distance from stationary units and azimuth, at pre-defined intervals. The device is mounted, but may be placed in a mobile vehicle.
A Fine Locating System, or simply FLS is a hand held receiver. This mobile, handheld approaching unit is used to receive/transmit data from/to the ARTU and from/to the CBS. The FLS is optionally provided with human-machine interface such as speaker, screen, LED array, and alike, to enable interactive approaching the specific animal, by a human operator. The ARTU attached to the animal is located by the FLS through use of a directional antenna or directional array of antennas (referred to as DAN).
The data gathered by the receiving and transmitting may be stored in a computer operable database and analyzed using a computer processor that performs calculations and comparisons of data with stored established standard values. The system may also include a clock that records the time and date that the data is received and transmitted. The computer operable system may also transmit information over a network such as but not limited to the Internet in order to facilitate remote monitoring of the animals.
FIG. 2 presents the operating modes of the present application 200 . One aspect of the present disclosure is to provide a lightweight, robust and low power consuming ARTU, comprising at least one electric power source, at least one receiving antenna, at least one transmitting antenna such that the receiving antenna and transmitting antenna may be same antenna, and at least one logic device able to store/process/manipulate data being received from external sources, as well as monitoring power level, power consumption rate, power consumption patterns, and duration of pulses. Said ARTU is characterized by three operation modes: The rest mode 210 is characterized by typical very low average power consumption of less than 1 milli-Watts (mW), more preferred less than 0.1 mW and most preferred less than 0.05 mW. It is an object of the present invention to provide said very low power consumption by switching between three different phases of the rest mode:
The coma phase 260 is characterized by very low power consumption of less than 0.1 mW, more preferred less than 0.05 mW, and most preferred less than 0.02 mW. The ARTU is being in this phase for at least 50% of the time, more typically at least 90% of the time and specifically at least 99% of the time. The low power consumption obtained by the ARTU is neither transmitting nor receiving signals from/to external units.
The cadet phase 250 is characterized by power consumption of less than 2000 mW, more preferred less than 200 mw and most preferred less than 100 mW, and the ARTU is being in this phase for at most 10% of the time, more typically at most 2% of the time and specifically at most 1% of the time. The ARTU is receiving signals from external sources such as the CBS, FLS or others. In a preferred embodiment, the ARTU becomes Cadet approximately every 1-1000 seconds; said period varies from 0.001 millisecond (ms) to 10 seconds. During cadet mode, the device is open to receive activating pulses 270 , commands, order, or other signals that are processed and may order it to become alert or operative according to a pre-defined programming, or due to request by operator of the FLS or optionally the CBS. Cadet is connected 255 to the coma phase 260 .
The synch phase 240 is characterized by power consumption of less than 2,000 mW, more preferred less than 200 mW and most preferred less than 100 mW, and the ARTU is being in this phase for at most 10% of the time, more typically at most 2% of the time and specifically at most 1% of the time. The ARTU is transmitting signals to external receiving unit such as the CBS, the FLS or others. In a preferred embodiment, the ARTU are synced every 1-100,000 seconds, sync period is typically less than 10 seconds. Sync period is characterized by a transmission of unique signals 276 from the ARTU. Said signal enables the FLS and/or CBS to recognize said specific ARTU, to provide useful data regarding specific ARTU and to establish time points for next cadet period or to order the ARTU to become Alert or Operative (see below). For example, the ARTU is transmitting a sync signal every 10-30 minutes. Said signal is being used as a time marker. As such, each relevant ARTU will have a “conference call” at specific pre-determined time point according to a pre-defined protocol. During said sync period, the coarse location of the specific ARTU is detected, registered, and stored by the CBS. The synch phase 240 is connected 265 to the cadet phase 250 and is connected 245 to the coma phase 260 .
A second module is the alertness mode 220 . It is connected 215 to the rest mode 210 . An object of the present invention to provide a mode of very power efficient and is responsive to receive commands/requests from the FLS and/or CBS. The term “responsive” means that the chance for obtaining commands from FLS/CBS is increased relative to Cadet phase during rest mode. Power consumption is higher during alertness mode, so alertness should be selected when the need to approach the specific animal is urgent and time is immediate. In a preferred embodiment, the ARTU becomes open to receive signals every 0.01-100 seconds, or more preferred 1-10 seconds, and said period of “open to receive signals” 272 is typically less than 10 seconds. By limiting the “open to receive signals” period of duration, average power consumption of the ARTU is kept very low. Unlike rest and operation modes, alertness mode is optional and in many embodiments an ARTU is switched between rest and operation modes. Alertness mode is characterized by typical low average power consumption of less than 10 mW, and may also consume less than 1 mW. A most preferred embodiment consumes less than 0.5 mW. It is another object of the present invention to enable registration of coarse position of the ARTU via at least 2 CBS units measuring signal power and/or propagation time between said ARTU and each CBS units, during alertness mode. Since communication between ARTU and CBS units during alertness mode is more frequent than rest mode, the accuracy if coarse positioning of ARTU may be improved by averaging of multiple readings. In one embodiment, said ARTU being in alertness mode is transmitting to two or more CBS units for every 0.1-5 seconds.
The operating mode 230 is linked 225 to the alertness mode and linked 235 to the rest mode 210 . The operation mode 230 contains the ARTU transmitting signals 278 at pre-defined rates and patterns, so FLS and/or CBS can easily trace it and enable the user operating the FLS to approach the specific ARTU and the animal that said ARTU is attached to. Signals may also be received 274 . Typical transmission pattern that provides efficient tracking of said ARTU is transmitting unique signals every 0.001 to 1000 millisecond (ms). One embodiment transmits every 0.01 ms to 10 seconds, whereas signal pulse duration may vary from 0.00001 to 500 ms or vary from 0.001 to 1 ms. In one preferred embodiment, approaching a specific active ARTU by FLS carried as a handheld mobile unit by a user is obtained by directing the FLS toward maximal power reception. Duration of said period may vary depending on the user of the system. This mode is characterized by typical very low average power consumption of less than 3 mW. A preferred mode consumes less than 0.3 mW and most preferred less than 0.15 mW.
Since this event is not very frequent, power consumption in this mode is similar to other known in art technologies, but due to the very short period, the contribution to average power consumption is low. Usually, even if approaching an ARTU is done few times per week, more typically up to 200 times per year, the average power consumption remains lower than 0.6 mW, and may be less than 0.2 mW.
Since the contribution of operation mode to power consumption is low, average long term power consumption is defined as the average power consumption during rest mode, measured for period of 1 week, in field operation, and is referred to by ALTP.
According to a pre-defined protocol and/or external command or signal, the ARTU can switch from each of the above-mentioned modes to any of said modes, for example, from rest directly to operation or in another example from cadet back to coma.
The three basic phases of rest mode are provided. The ARTU can switch between the 3 phases according to a pre-defined procedure, or can be re-programmed during cadet phase by receiving commands from the FLS or optionally CBS. The RECEIVE 1 symbol 270 represents signals from the CBS/FLS or other devices that are received by the ARTU during its cadet phase. The TRANS 1 symbol 276 represents signals transmitted from the ARTU during sync period. The RECEIVE 2 symbol 272 represents signals from the CBS/FLS or other devices that are received by the ARTU during its alertness phase. Signals are either activating the ARTU to become “operative” meaning being in operation mode or order it to become alertness or rest again. The RECEIVE 3 symbol 274 represents signals from the CBS/FLS or other devices that are received by the ARTU during its operation mode. Said signals are commanding the ARTU to stay at operation mode or to switch to rest again. The TRANS 2 symbol 278 represents signals transmitted from the ARTU during the operation period and are usually identified and processed by the FLS for the approaching procedure.
In one embodiment, the transmissions and receiving are carried at radio frequency range of 0.3-20 GHz. Due to the low power consumption, the ARTU according the present invention may be operated by battery, typically of 500-5000 mAh (milliamper-hour), for period of 2 years typically, with a maximum battery life of 5 years or more.
Another object of the present invention is to provide a power saving and time saving method for approaching an individual animal, by registering the ARTU location, every time the ARTU is transmitting signal toward the CBS, at CBS or at central data system. The specific “zone” or “coordinate” is stored. Event of transmission occurs every time ARTU provides a sync signal. When searching the specific animal with the FLS, the search is focused to the last registration “zone” or “coordinate” that can be found relative to azimuth and distance from one or more CBS or the intersection point of two or more CBS's. The pre-registration and the resulting focused search shorten the approaching time and thus saving power of the ARTU. This saves time of a farmer, dairyman or veterinarian and may save life of animal in a case of emergency.
FIG. 3 presents the method of operation 300 . Another object of the present invention is to provide a method for approaching an individual animal in a group of animals, located in a paddock or in a pen. Said method comprises the following steps:
Providing an ARTU attached to an individual animal, characterized by ALTP of less than 0.5 mW 310 . Optionally, registering an ARTU coarse positioning according to signals transmitted during sync and/or alertness period and received by at least two CBS units 320 . Switching said ARTU to operation mode, either through alertness mode or directly from rest mode during cadet phase, by a command from FLS and/or CBS 330 . Transmitting signals from operative ARTU 340 . Providing a FLS as a handheld mobile device 350 . Optionally, obtaining coarse position at FLS of said specific ARTU, from data system according to data obtained through CBS units 360 . Obtaining signals transmitted from ARTU by FLS, processing said signals and providing said result to human operator via a human-machine interface 370 . Guide human operator toward specific animal, according to maximal signal power 380 . Approaching specific ARTU and animal attached to said ARTU, 390 .
ARTU comprises a battery power source of 2000 mAh. One type of battery that may be used is a lithium battery to power a low power microprocessor (MP) such as, but not limited to, MSP430 USA, RF module such as ZIGBEE module at frequency of 2.4 GHz, manufactured by TI from USA. The frequency of the omnidirectional antenna is in the frequency range of 2.4-2.5 GHz. The antenna is inside a plastic or metal enclosure to protect said components from dirt and humidity. The ARTU is attached to an animal by any means providing long lasting operation. The ARTU average current consumption during coma phase is less than 40 micro Watts, since the RF module is off such that transmission is disabled. During cadet and sync phases, the ARTU average power consumption is less than 40 mW. The difference from coma phase is because the RF module is on so that receiving and transmission is enabled.
The time allocation between phases in rest mode is approximately every 2 minutes the ARTU switches from coma to cadet and stays at cadet phase for about 5 milliseconds. Under this combination, average power consumption of rest mode may be less than 40 microwatts because of the short periods of cadet mode. Approximately every 10 minutes the ARTU transmits sync signal for providing FLS and, optionally, CBS, an animal-specific data, including identity, time, power status and alike, as well as opportunity for CBS units to calculate coarse location of the ARTU. The sync period enables the FLS to provide ARTU commands, such as, for setting an accurate time slot for next communication event, command to become operative or alertness, and also optionally enables registration of coarse location via CBS system.
The ARTU is activated to alertness mode by receiving a specific command from mobile handheld antenna (FLS) and/or CBS during its cadet phase. During alertness mode, the ARTU becomes open to receive/transmit RF once a second for period approximately 5 milliseconds. Power consumption during alertness mode is less than 400 microwatts. The advantage of alertness mode over cadet mode is by increasing readiness of the ARTU to obtain commands from mobile handheld antenna and/or CBS, and to provide more time for CBS units for calculating position of the ARTU.
FIG. 4 presents a method 400 of using the hand held FLS for approaching an animal. The handheld antenna such as FLS unit for approaching the ARTU comprises a directional antenna in the frequency range of 2.4-2.5 GHz such as micro-strip, phased array or horn, a power source—usually a battery, a microprocessor or computer and a man-machine interface, such as speakers or display, for providing feedback on signal level and thus enabling approaching the specific animal.
The approaching procedure in the specific example comprises the steps:
a) Activating FLS and/or CBS, 410 b) CBS and/or FLS are transmitting command/s for a period of at least 2 minutes, 420 . c) Optionally to (2) if a time slot for sync in known, FLS and/or CBS are transmitting command for period of few milliseconds to ARTU, 430 . d) Optionally, once a command of “become alert” is received, the ARTU enters alertness mode, 440 . e) Once a command for becoming operative is received and processed by ARTU, the ARTU enters operation mode and transmits signals at a rate of 10 times per second, each time for a period of 1 millisecond and power during said 1 millisecond is 40 mW, 450 . f) FLS mobile handheld antenna is receiving said signals from ARTU and optionally a coarse positioning from CBS. By searching for maximal signal via the man-machine interface, one can easily approach the specific animal, 460 .
The present disclosure has been described with reference to exemplary embodiments. Obviously, modifications and alterations will occur to others upon reading and understanding the preceding detailed description. It is intended that the present disclosure be construed as including all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof. | A system and method of tracking animal livestock using electronic frequency signal transmitters and receivers is herein presented. The system involves electronic tags attached to the bodies of livestock. The tags transmit a signal which conveys the location or other pertinent information regarding the status of the animal. The signals are picked up by a receiver attached to a stationary platform, or located in a vehicle, or in a portable hand held receiver device. The information transmitted can be used to locate a specific animal or can be used to monitor the status and condition of the animal. The device contains several modes which minimize power consumption and maximize power supply lifetime. | 6 |
BACKGROUND OF THE INVENTION
This invention relates to corpuscular radiation equipment in general, and more particularly to a magnetic lens system operating in a vacuum and comprising an improved arrangement of a shield housing, a superconducting shield, one or more lens coil windings, and a vacuum chamber for receiving the object to be examined.
One objective lens system for an electron microscope is known from U.S. Pat. No. 3,916,201. Its superconducting shielding device consists of two hollow cylindrical shielding bodies which are arranged in tandem in the beam direction axis and which closely surround the space in which the beam is conducted. The two shielding cylinders contain superconductive material which, in the operating condition, is kept below its so-called transition temperature by means of a cryogenic medium such as liquid helium. Between the adjacent end faces of these shielding cylinders a gap is developed, in which a vacuum chamber is arranged. Into this chamber an object to be examined may be introduced radially from the side by means of a separate insertion device. Because the objective space is also cooled by the cryogenic medium, lateral migration of the object due to temperature, the so-called thermal drift, can be kept extremely low, in some instances, to less than 0.03 nm/min.
Each of the two shielding cylinders is surrounded by a superconducting lens coil winding, which is short circuited in the operating condition. The effect of these shielding cylinders is that the magnetic field generated by the lens coil windings can act on the corpuscular beam only in the vicinity of the lens gap. The shielding cylinders therefore extend at their antipodal ends to regions of negligible field strength.
The two shielding cylinders are further connected to a shield housing of superconductive material which directly encloses on all sides the lens coil winding arranged around the shielding cylinders, except for the portions of the surface facing the shielding cylinders. Kept in the superconducting state, the shield housing limits the extent of the magnetic field produced by the lens coil windings, and shields the gap region to a high degree against external magnetic interference fields, particularly alternating fields.
It is well known that the resolution of corpuscular radiation equipment depends on the so-called aperture error constant of its lenses, and in particular, of its objective lens. The size of the lens gap between opposite end faces of the two shielding cylinders is therefore chosen in presently used electron microscopes so that very small values are achieved for the aperture error constant C O , the chromaticity error constant C F and the focal length f. The aperture error constant depends on the maximum value H O of the field intensity or, equivalently, the maximum value B O of the magnetic induction in the lens gap, i.e., the region in which the magnetic field acts on the corpuscular beam. The constant also depends on the field gradient along the beam direction axis in the lens gap. Assuming an approximately Gaussian axial distribution of the field intensity in the lens gap, the half-width of the Gaussian determines the field gradient for a given maximum field strength. This half-width depends on the dimensions of the two shielding cylinders used for forming the lens gap in the vicinity of their opposite end faces. Both the distance between the two shielding cylinders, i.e., the gap length in the beam direction, and the shape of the shielding cylinders in the vicinity of the opposing end faces affect the half-width.
Such an objective lens system, with an aperture error constant C O of about 1.45 mm, a gap width of 5 mm, a maximum induction of 2.1 Tesla, and a half-width of 4.4 mm, was tested in an electron microscope with a beam voltage of 220 kV. It was possible to reach the theoretical resolution limit. Cf. Optik Vol. 45 No. 3 at 291-94 (1976). The objective lens system described therein is particularly suited for electron microscopes of the so-called fixed-beam type, in which a focused electron beam, held immovable by means of magnetic fields, irradiates an object, of which a magnified image is generated by means of downstream magnetic magnification lenses.
The known objective lens system, however, is not directly applicable to the so-called transmission-type scanning electron microscopy. In this technique, a sharply focused electron beam sweeps over the surface of the object to be examined according to a predetermined raster pattern. This primary electron beam generates secondary electrons at every point of the surface. If these secondary electrons, as well as possible Auger electrons and backscatter electrons are to be collected for additional energy dispersion analsyses, then the appropriate detector devices must be arranged in the immediate vicinity of the object. However, this is not directly possible with the known objective lens system, as the object space is too small. For beam voltages under 250 kV, sufficient space can be gained by enlarging the lens gap only if an increase of the aperture error constant C O , the chromaticity error constant C F and the focal length f by about one order of magnitude can be tolerated.
SUMMARY OF THE INVENTION
It is the object of the present invention to rearrange the known objective lens system in such a manner that an electron microscope equipped therewith may be set up for transmission-type scanning electron microscopy without the need of abandoning important advantages of the known fixed-beam electron microscope objective. In this arrangement, the object to be examined should exhibit a very small thermal drift, and the corpuscular beam should at the same time be well shielded against external magnetic interference fields. In addition, it should be possible to tilt the object, and to perform on it energy dispersion analyses.
The present invention satisfies these requirements with a single superconducting cylinder as the shielding device. Between the one end face of the device and the corresponding flat side of a lens coil winding about the cylinder, on one side, and the inside of the superconducting shield housing facing these surfaces, on the other side, a cavity is formed in which the vacuum chamber for receiving the object to be examined is arranged.
This embodiment of the lens system has the particular advantage that it can be used simultaneously for scanning electron microscopy and for fixed beam electron microscopy, as the cavity in the interior of its shield housing can be made large enough to accommodate a vacuum chamber for the object to be examined as well as detectors for energy dispersion analyses. The maximum field strength on the cavity side of the free end face of the single shielding cylinder is sufficiently high for scanning electron microscopy, and the half-width of the corresponding field curve is small enough to keep the imaging errors of the lens system small.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of a first embodiment of the lens system of the present invention.
FIG. 2 is a cross-sectional view of an alternate embodiment of the lens system of the present invention.
FIG. 3 is an illustration of the field strength distribution produced in one corresponding embodiment of the objective lens of the invention.
DETAILED DESCRIPTION OF THE INVENTION
The objective lens system shown in FIG. 1 is suitable for a transmission type scanning as well as for a transmission type fixed-beam electron microscope. The parts of the microscope not shown in this figure are known per se, and can correspond, for instance, to the parts of the electron microscope disclosed in the U.S. Pat. No. 3,916,201. The objective lens system comprises a hollow cylindrical closed shield housing 2 which consists of superconductive material and which is held, in the operating condition, at a temperature below the critical temperature of the material by means of a cryogenic medium. It contains a bottom part 4 and a top part 5, each provided with a central opening 7 and 8, respectively, through which an electron beam directed along an axis 10 is conducted through the shield housing. In the interior of the shield housing a shielding cylinder 12 with a central bore hole 13, which has a relatively small diameter, stands concentrically to the beam direction axis 10, on the bottom part 4. The shielding cylinder likewise consists of superconductive material, and can form a common shaped piece with the shield housing 2. It is advantageously cooled by the same cryogenic medium which is required for the shield housing 2. The shielding cylinder 12 is furthermore surrounded by a current carrying lens coil winding 15 which fills the annular space formed between the shielding cylinder and the side wall 17 of the shield housing 2. The conductors of the coil winding 15 are also superconductors, so that the coil winding can be short circuited in the known manner in the operating condition. The upper flat side 19 of this annular coil winding 15, which is antipodal to the bottom part 4, projects slightly beyond the corresponding end face 21 of the shielding cylinder 12. The top part 5 of the shield housing 2 does not rest immediately against the upper flat side 19 of the lens coil winding 15 or the upper end face 21 of the shielding cylinder 12; instead a predetermined distance a is formed between the parts 5 and 19. As a result, a cylindrical cavity 23 above the lens coil winding 15 and the shielding cylinder 12 is obtained within the interior enclosed by the shield housing 2. In this cavity 23, a vacuum chamber 25 is arranged, into the object space 26 of which an object 28 to be examined may be inserted from the side by means of a specimen slide 27 and may be brought into the electron beam in front of the free end face 21 of the shielding cylinder 12. The devices required for introducing the object 28 into the object space 26, as well as for mounting, are known and not shown in the figure.
To direct the electron beam through the object 28 according to a raster pattern, two suitable deflection systems 30 and 31 are included in the embodiment of FIG. 1. The first deflection system 30 is located outside the shield housing 2 in the immediate vicinity of the top part 5, while the deflection system 31 is arranged on the inside of the top part within the interior 23 enclosed by the shield housing 2. This further deflection system 31 can serve simultaneously as a stigmator system, by means of which deviations of the magnetic fields from rotational symmetry can be corrected. These coils for correcting the direction of the guided beam may contain superconducting material, and may be cooled by the same cryogenic medium as the shielding device.
In the objective lens system of a transmission-type scanning electron microscope only a resolution of the order of 0.3 nm is necessary. The maximum field strength along the beam direction axis 10 in front of the free end face 21 of the shielding cylinder 12 needs therefore to reach only a relatively low value, in the order of one Tesla. Hence, the cavity 23 inside the shield housing 2, and likewise the vacuum chamber 25, can be made large enough to accommodate additional devices for further radiation analyses in proximity to the object 28. In the figure, a detector 33, which is to contain a suction device for imaging with Auger and secondary electrons, a backscatter electron detector 34, and a ring detector 36 of lithium doped silicon for energy dispersion X-ray analysis are indicated. Diaphragms 37 may also be provided in the object space 26 directly below the object to be examined. In addition, the object may be tilted, i.e., the angle made by its surface normal to the beam direction axis 10 varied to a predetermined value, so that the direction of definite crystal axes may be taken into consideration in examining the object.
The density of the electron beam for transmission type scanning electron microscopy is generally relatively high, so that a correspondingly high contamination of the object might be expected. In the lens system according to the present invention, however, contamination is practically impossible as the object stage is deep cooled from the start; as the vacuum chamber 25 is enclosed on all sides by deep cooled components, the object space 26 and therefore also the object are at the very low temperature. Drift due to thermal causes is therefore as low as is that due to external interference fields, which are kept from the object space 26 by the shield housing 2, and may be of the order of 0.01 nm/min.
The electron beam leaves the shield housing 2 via the opening 7 of the bottom part 4. At this point, a further stigmator system 38 may be employed to correct the magnetic fields acting on the electron beam. Again, these may be superconducting in the operating state. The post-magnifying lenses of the electron microscope following thereupon in the beam path are known per se, and are only indicated in the figure by a double arrow 40. At the end of this post-magnifying lens system there is a detector 42 for picking up the electrons inelastically scattered in the object 28.
Unlike the embodiment of the objective lens system according to FIG. 1, which is suitable for a scanning as well as for a fixed beam electron microscope, the objective lens system according to FIG. 2 can be used only for electron microscopes of the scanning type. A detector 47 which is required for registering the electrons elastically scattered in the object 28 can therefore be arranged within the objects space 26 of the vacuum chamber directly under the object 28. This detector 47 can also pick up all elastically scattered electrons. In the vacuum chamber 25 are also depicted the devices for radiation analysis discussed for the FIG. 1 embodiment. The deflection systems 49 and 50, required for deflecting the electron beam in the scanning technique, are arranged outside the shield housing 2 above the top part 5 concentrically with the beam direction axis 10. A stigmator system 52 is further provided between the detector 47 for registering the scattered electrons and the free end face 21 of the shielding cylinder 12. In addition, a spectrometer 54 is indicated in the figure, following the objective lens system and by which the energy loss of the inelastically scattered electrons can be measured. The aperture angle defined by the diameter of the bore holes 13 and 7 in the shielding cylinder 12 and the bottom part 4 of the shield housing 2, respectively, is sufficient therefor. The other parts designated in the figure correspond to those in the lens system according to FIG. 1.
In FIG. 3, the axial field distribution in an analysis objective according to FIG. 1 or 2 is reproduced in a diagram. The position z of the measuring points in front of the free end face 21 of a shielding cylinder 12, which is surrounded by a lens coil winding 15, is given on the abscissa in the beam direction in millimeters, while the measured magnetic induction B O in Tesla is plotted on the ordinate. The field distribution measured in FIG. 3 is based on an embodiment example of an objective lens system with the data shown in the following Table 1:
Table 1______________________________________Diameter of shield housing 2 100 mmLength of shield housing 2 100 mmLength of shielding cylinder 12 40 mmDiameter of bore hole 13 of the shielding cylinder 12 3 mmOutside diameter of coil winding 15 60 mmInside diameter of coil winding 15 20 mm______________________________________
The effective current density in the lens coil winding 15 is about 1.5×10 4 A/cm 2 . This results in a value of the maximum induction B O of the field in front of the shielding cylinder 12 of about 1.4 Tesla.
The electron-optical parameters obtained with these data depend on the beam voltage of the electron microscope and are given in the following Table 2.
Table 2______________________________________ Beam Voltage 150 kV 250 kV______________________________________Front focal length f.sub.v 2.2 mm 2.9 mmRear focal length f.sub.H 9.8 mm 10.6 mmAperture error constant C.sub.o 1.75 mm 2.7 mmChromaticity error constant C.sub.F 1.7 mm 2.2 mmFocal point coordinates:Front focal point coordinate z.sub.V or z.sub.V' -0.5 mm -2 mmRear focal point coordinate z.sub.H or Z.sub.H' -15 mm -11 mm______________________________________
The zero coordinate z o , to which the focal point coordinates are referred, is assumed to be that location on the abscissa, at which the induction B o assumes its maximum value. The focal point coordinates obtained with a beam voltage of 250 kV are noted by a prime to distinguish them from the corresponding coordinates obtained at 150 kV.
As can be seen from Table 2, the front and rear focal point coordinates z V ' and z H ' are closer together at the higher beam voltage of 250 kV than at the lower beam voltage of 150 kV. The distance between the focal point coordinates associated with each beam voltage is, on the one hand, large enough to avoid multiple constrictions of the electron beam, which lead to difficulties in adjusting the lens system, and on the other hand, small enough to allow a short overall design of the electron microscope. For transmission type scanning electron microscopes with the lens system according to the present invention, relatively low beam voltages between 100 and 500 kV can therefore be provided; the lens power can be kept under k 2 =5.
In the embodiments according to FIGS. 1 to 3, it is assumed that the cavity 23 is always located ahead of the shielding cylinder 12, as seen in the direction of the beam. The cavity can equally well also be provided behind the shielding cylinder 12, i.e., the shielding cylinder 12 with the coil winding 15 can be accommodated in the upper part of the space enclosed by the shield housing 2. The object to be examined then would have to be arranged below this cylinder.
In addition, the top part 5 of the shield housing 2 may also consist, if appropriate, of ferromagnetic material. | A magnetic lens system for corpuscular radiation equipment operating in a vacuum, in particular, an objective lens system for electron microscopes, comprising a superconducting shield housing, in which are arranged, at one end, a single hollow cylindrical superconducting shielding device, wound with a lens coil, and at the other end, in front of the free end face of the shielding device, a vacuum chamber for accommodating an object to be examined, permitting the cavity to be relatively large, and detectors for radiation analysis to be arranged therein so that the lens system is therefore suitable for use in scanning electron microscopes. | 7 |
This application is a continuation of application Ser. No. 626,475, filed July 2, 1984, which is a continuation of Ser. No. 498,035 filed May 31, 1983 which is a continuation of Ser. No. 174,407 filed Aug. 1, 1980, all now abandoned.
BACKGROUND OF THE INVENTION
In the French Pat. No. 76 35439 published under No. 2370874 filed Nov. 16th, 1976 by the applicant, there is described a turbine rotating at speeds of the order of 3000 rotations per minute for example and adapted to drive tools such as brushes or the like, intended especially for underwater operations.
This turbine can be driven by a motor pump providing water under a pressure or several bars with an output of the order of one to several tens of cubic meters per hour, and permits the construction of portable apparatuses.
According to the said patent, the turbine comprises a distributor presented in the form of a passage without blades which communicates, with the blades of a rotor with four blades, by means of injectors constituted by openings formed between portions of a circular stator ring, in number double that of the blades, the water escaping axially to the centre of the rotor chamber.
Subsequent work of the applicant has permitted him to discover that such a turbine only functions correctly and with a satisfactory output if a certain number of conditions of shape and of dimensions are respected.
Consequently, the turbine according to the invention is principally characterised in that the blades have a profile of an arc of a circle, that the portions of the stator ring which define the injectors each have a plane terminal face inclined at substantially 45° to the corresponding radius of the respective portion of ring and, for a first injector, forming an angle substantially equal to 135° with the plane tangential to the external surface of the corresponding blade, when this latter occupies a position in which an adjacent blade is on the point of commencing to cooperate with the respective injector.
According to another feature of the invention, in the said position of a blade, it cooperates with a second injector the plane terminal face of which forms an angle substantially equal to 120° with the plane tangential to the external surface of the said blade and the difference of inclination of the two consecutive jets acting on the same blade is always substantially equal to 15°.
Another feature of the invention is that the ratio between the external radius of the said arcs of a circle and the internal radius of the said stator ring is substantially equal to 3/4.
BRIEF DESCRIPTION OF THE DRAWINGS
Other features, as well as the advantages of the invention, will appear clearly in the light of the following description.
In the accompanying drawing:
FIG. 1 is a view in elevation and in section, on a reduced scale, of a turbine in accordance with a preferred manner of carrying out the invention;
FIG. 2 is a view in section taken on a plane perpendicular to the axis of the rotor, the rotor being removed;
FIG. 3 is a schematic view of the rotor, showing the blades; and
FIG. 4 is a diagram intended to show the positioning of the blades and of the injection ring.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings, in FIG. 1, the stator of the turbine is composed of a principal body 1 closed by a plate 2 fixed to the body 1 at its periphery by means of bolts 20.
As can be seen in FIGS. 1 and 2, the body 1 defines a passage 3 closed by the plate 2 and provided at 30 with a water admission opening and a flat cylindrical chamber 4 which receives the rotor 5, the shaft 6 of which passes axially through a circular opening 7 formed in the base of the chamber 4 and is journalled in this opening. The opposite face of the rotor comprises a hollow axle 8 which is journalled in a bearing 9 formed by the central part of the plate 2 and externally threaded. The bearing 9 is itself capped by a retaining ring 10 serving for the coupling of a curved conduit 11 movable in all directions and provided with a pipe 12.
The external circular wall of the chamber 4 is constituted, in the preferred manner of construction described, of eight portions 41 to 48, fast with the body 1. The plate 2 is fixed on the body 1 by means of bolts 13 and 20. These portions, which each cover an angle equal to 45°, are separated one from another by spaces 410-420-430-440-450-460-470 and 480, closed at the top by the plate 2 and constituting injectors of water from the passage 3 towards the chamber 4. Each injector is bounded by a plane surface, such as 441 of the portion 45 (FIG. 4) inclined at 45° with respect to the corresponding radius of the rotor and by a cylindrical surface 442 which joins with the internal and external cylindrical surfaces of one of the portions 44. The developed shape of the passage 3 in a plane perpendicular to the axis of the rotor has the general form of an isosceles trapezium the major base of which corresponds to the opening 30 and the minor base of which is in the zone of the injector 480. The sides of this trapezium when extended form an angle of about 87° with its major base. In its part which communicates with the central chamber, the passage 3 has a rectangular section (FIG. 1) comprising two chamfers 31-32 inclined at 30°.
The rotor (FIGS. 1, 3 and 4) is formed of two discs 51,52 having a diameter substantially equal to that of the chamber 4 (a play of 1% between the diameter of the rotor and that of the chamber of the stator is advantageously provided) and between which are provided four blades 53 to 56, the lower disc 52 not being provided with any opening, whilst the upper disc 51 is provided with the base opening of the hollow shaft 8; in other words, the water which enters through an injector I 1 (FIG. 4) works in a chamber bounded, on the arrival side, by two cylindrical portions of the wall of the chamber 4 of the stator and by two blades, and on the exit side, passing out between the ends of the two blades, in the region of the opening of the shaft 8, through which it escapes.
FIG. 4 shows that, the rotor being positioned as illustrated in this figure, for a radius ROI 1 of the rotor having a centre O, of 59.5 cm., the centre O' of the blade 56 will be determined with 41.5 mm of internal radius and 45 mm of external radius, by tracing a right-angled triangle O HO' with OH=19 mm and HO'=5 mm, which corresponds to OO'=19 mm 65.
More generally, the four centres of the arcs of circle which constitute the blades will preferably be situated on a circumference of centre O and of radius 0.33 R. These four centres are thus situated on two orthogonal axes.
There has been considered, in FIG. 4, a position of the rotor wherein an end A of the blade 56 is just coming level the lower edge of an outlet opening of an injector (more precisely in which the internal arc of a circle of the blade joins to the stator wall at the point where the latter is cut by the straight line OHI 3 ). The other end B of the blade 56 is then on a radius O'B, such that the angle at the centre BO'-A is substantially 140°. Preferably, the end corresponding to A is a portion of circular surface parallel to the opposed stator surface, the play between these two surfaces being about 1% of the diameter of the rotor.
The radius of the cylindrical surface (such as 442) of each injector is advantageously 25 mm.
According to an essential feature of the device described, in the position of the rotor shown in FIG. 4 (wherein the internal wall of the outer end of each blade joins to the internal surface of the chamber in the region of one injector of two) the directions I 1 T 1 and I 2 T 2 , parallel to the flat walls of the injectors (that is to say inclined at 45° to OI 1 and OI 2 , I 1 and I 2 being the centres of the rectangular windows, 10 mm long and 2 mm wide in the example described, through which the injectors open into the chamber 4) are respectively inclined at 135° and 120° to the tangents to the blade at T 1 and T 2 (there are half-tangents T 1 x 1 and T 2 x 2 directed from right to left).
In order to operate the turbine which has been described, water is injected under pressure (from 0.3 to 10 bars and preferably of the order of 3 to 5 bars for example) through the opening 30 (to which a motor pump is connected). The water enters into each working chamber through two injectors, respectively in the directions I 1 T 1 and I 2 T 2 . The corresponding forces of impact on each blade, in the position of the rotor shown in FIG. 4, have respective tangential components directed as T 1 x 1 and T 2 x 2 . As a result there is a couple with respect to the centre O and the rotor is driven in rotation in the clockwise direction.
It will be noted that, as a result of this rotation, the blade 56 will immediately cease to receive the impact of the water ejected at I 1 , whilst it will continue to receive the impact of the water injected at I 2 and commences to receive the impact of the water injected at I 3 , until I 2 T 2 in its turn makes an angle of 135° with T 1 x 1 . At the same time, the blade 53 will commence to receive the jet injected at I 1 , substantially at an angle of 120° with the tangent. Put in another manner, the angles of 120° and 135° substantially constitute the maximum and minimum values of the variable angle which each of the two jets of water injected on each blade makes with the tangent to the blade. Further, the difference of inclination of the jets is always equal to 15°.
Trials carried out by the Applicant have shown that the output of the turbine decreases rapidly when the maximum angle I 1 T 1 x 1 departs from the critical value of 135°. When the said angle passes for example from 135° to 145°, the output can diminish by 30%, whilst it diminishes by 40% if the angle passes from 135° to 125°. Outside these limits, one might consider that the turbine is no longer adapted to function in practice, the rotor being able to cease rotating.
It is to be noted that the jet of water injected at I 1 in the position of FIG. 4 divides itself, after impact on the blade, into a portion which escapes rapidly and directly towards the outlet of the chamber and a portion which finds itself so to speak jammed in the narrow part of the chamber; it forms vortices and risks the causing of an excessive slowing of the rotor if it represents a too large portion of the jet, which is the case when the maximum angle exceeds substantially 135°. In the case where, on the contrary, the maximum angle is substantially lower than 135°, then on the one hand the tangential component of the impact force of the jet diminishes, and on the other hand the proportion of the jet which escapes directly towards the outlet increases, so that the output falls very rapidly. In practice, it will be held to the value of 135°, the variation having to remain lower than 5°.
The trials have likewise shown that the value of the minimum angle of impact at I 2 is critical (not having to vary from the value of 120° by more than 10% and, preferably 5%). When the minimum angle departs from the values indicated, there are found the same phenomena as when the maximum angle is caused to depart from the optimum value.
Preferably, the difference between the two extreme angles must moreover substantially not depart by more than one degree from the critical value of 15°.
The angular values mentioned above and which constitute an essential feature of the invention will have to remain the same if the turbine has dimensions different from those mentioned, or works at different pressures.
The structure of the turbine is finally principally characterised by the number of the blades (which will always be equal to four), the number and the disposition of the injectors (eight injectors having a surface such that the principal direction of the jet shall be substantially inclined at 45° to the corresponding radius of the stator and substantially positioned at 45° one from another), the shaping in the form of an arc of a circle of the blades and the said angular values, the principal one of which is constituted by the value of 135° defined hereinabove.
Nevertheless, other features will be found to be important.
The principal one of these supplementary features is the ratio between the external radius of the blades and the radius of the rotor, which ratio is substantially equal to 3/4 in the manner of construction preferred and described above. It will be noted that upon this ratio there depends the greater or lesser widening of each of the chambers in which the water works. The optimal escape of water is moreover related to the value (140') of the angle BO'A. All of the dimensions indicated in the example described are clearly valid for a close homothesis.
It is convenient to note here that the ratio of radii mentioned above determines in practice the position of the centre O' when one has fixed the radius of the rotor and the values of the maximum and minimum angles I 1 T 1 x 1 and I 2 T 2 x 2 . In effect it is then a question of tracing an arc of a circle (56, FIG. 4) of given radius which passes through the known point I 3 and cuts the half-lines I 1 T 1 and I 2 T 2 of known position at two respective points T 1 and T 2 such that the angle T 1 O' T 1 makes 30° and that the tangent T 1 x 1 to this circle shall be perpendicular to O 1 I 1 .
Another supplementary feature is the presence of a play, preferably of the order of 1% of the diameter of the rotor, between the latter and the stator chamber 4. This play permits a certain passage of water between the working chambers and it will be seen that the output decreases if it is reduced or increased with respect to the value indicated. A play, preferably substantially equal to 3% of the height of the stator chamber, is likewise provided between the latter and the opposed surfaces of the discs 51 and 52. This play, which is not shown in FIG. 1, permits axial balancing of the rotor and avoids jammings which particularly harm the output.
Another supplementary feature is the value, preferably equal to 87°, of the angle defined hereinabove for the passage 3. The lateral walls of this passage are thus inclined at 3° with respect to the median direction of the flow of water admitted into the turbine. As a result there is a good flow of water along the walls of the passage and the progressive reduction of the water admitted by the successive injectors, which is finally favourable to its good operation.
Another supplementary feature resides in the value, preferably equal to 30° as indicated above, of the angle formed by the chamfers 31,32 (FIG. 1) with the upper and lower walls of the passage 3, at the side of the rotor; it has been found that these chamfers facilitate the sliding along of the water and likewise facilitate the axial balancing of the rotor.
A last feature is constituted by the preferential minimum value of the ratio between the surface of the propulsion jet (that is to say of the internal section of the end of the pipe 12) (FIG. 1) and the total surface of the eight admission windows for water into the stator chamber 4. It has been indicated above that each of these windows was 10 mm×2 mm, in the construction described, which gives a surface of 160 mm 2 for the whole assembly. It has been found that the said internal section should preferably have a minimal section of 180% of this value, or at least 288 m 2 . In the example described, it is a circle of 20 mm diameter. If this condition is not respected, the counter-pressure due to the escape of the water jet through the pipe brakes the rotor of the turbine.
It will be noted that when it is not desired to utilise an effect of propulsion in the water of the assembly constituted by the turbine and by the tools which are associated with it, which effect is provided by the jet which escapes through the pipe, the curved conduit 11 and the pipe 12 can be eliminated, the escape of the water then being free.
The turbine described can be manufactured at low cost by using molded plastics materials. It is obvious that various modifications of shape and of dimensions could be applied thereto, without nevertheless departing in any great extent from the limits imposed by the conditions fixed hereinabove, which are essential to its good operation with an acceptable output. | A hydraulic turbine is of the kind having a distributor including a passage, without blades therein, which communicates with the movable blades of a rotor, having four blades, by means of injectors constituted by gaps formed between adjacent portions of a circular ring, the number of which is double that of the blades. The water escape axially to the center of the rotor chamber. The improvement of the present invention is that, in combination, the blades have a profile of an arc of a circle, and the portions of the stator ring which define the injector gaps each have a plane terminal face inclined at substantially 45° to the corresponding radius of the respective portion of the ring and, for a first injector, forming an angle of substantially 135° with a plane tangential to the external surface of the corresponding blade, when that blade occupies a position in which an adjacent blade is about to cooperate with the respective injector. | 5 |
This is a continuation of application Ser. No. 08/806,316, filed Feb. 26, 1997 now U.S. Pat. No. 5,783,033, the disclosure of which is incorporated herein by reference.
FIELD OF THE INVENTION
This invention relates to a device for applying or adhering two substantially planar discs each having a central aperture so that they are concentrically aligned. More specifically, the invention relates to a device for centering and applying labels to compact discs.
BACKGROUND OF THE PRIOR ART
Present electro-optical storage devices include Compact Disc Read Only Memory devices (CD-ROMs) that store digital information. The information is either or both audio and visual in nature. The information can also include data. CD ROMs comprise a plastic or "glass" disc that is coated with a metallic surface. The surface is etched or cut such that when placed in a CD ROM reader and spun at high speed, the etched pattern may be identified by a laser or other scanning method.
By their form, function and manufacture, CD ROMs are generally indistinguishable from one another. It is also generally difficult, if not impossible, to identify the nature or content of the information on a given CD ROM by visual inspection alone. It is therefore necessary to provide CD ROMs with a physical, unique mark or label.
The capability of a CD ROM to faithfully represent the information contained thereon is in large part dependent on the ability of the disc to be placed into a sustained, steady high speed spin about its physical center. This high speed spin presents complications to the marking methods employed.
Traditional ink based marketing methods in which the ink is applied directly to the disc must use an ink that will remain in place during sustained high speed spin. Additionally, the ink must be non-deleterious to the material of the disc. Use of conventional writing instruments, such as felt tip pens, is generally unsatisfactory since the ink may particulate and separate from the disc with the potential for becoming lodged in the mechanism of the disc reader. In addition, marking in this way does not present a professional appearance, especially if the CD ROMs are to be sold or used commercially.
Printers specially adapted for printing onto compact discs are available. However, the cost of such printers is prohibitive to those who produce CD ROMs in low volumes.
An alternative to using an ink marker directly on the disc is to use a label, usually a self-adhesive label, that is subsequently attached to the disc. Because of the high speed at which the disc must be spun, it is essential that the label be affixed in such a way that the overall balance of the disc is not adversely affected. In particular, it is necessary that the center of balance of the disc remains about its geometric center. Labels which are not concentrically affixed to the discs, for example, "half-moon" or semi-circular labels, have previously caused malfunctions and often rendered the discs virtually useless.
A known manual device for concentrically applying a self-adhesive label to a compact disc comprises a first member having a cylinder closed at one end by a slightly convex exterior face with a central aperture corresponding approximately to the size of the central aperture of the label, and a second member having a first portion with a diameter approximate to the diameter of the aperture of the first member and a second portion having a diameter approximate to the diameter of the central aperture of the compact disc. The first and second portions together form a shoulder against which the compact disc is seated.
In use, the operator must initially position an adhesive label on the first member so that its adhesive surface is uppermost. The label aperture is aligned with the central aperture of the end face of the cylinder. This step alone can be difficult because of the tendency of the label to stick to the operator's fingers and hence move off-center when the operator attempts to withdraw his/her fingers in order for the compact disc to be pressed onto the label. Also, there is a tendency for the label to curl upwards when the operator is not holding the label down.
Once the label is in its desired position on the first member, the compact disc which is retained against the shoulder portion of the plunger can be pressed down onto the label. In order to achieve the desired concentric alignment between the label and the disc, it is necessary to press firmly the disc against the shoulder portion while pushing the first portion of the plunger through the aligned apertures of the first member and the label.
Since the surface of the first member against which the label and compact disc are pressed is not planar, further care has to be taken to ensure that no air bubbles are trapped between the label and the disc. Such air bubbles are not only unsightly, but may also cause balancing problems in the CD ROM reader.
It will be appreciated that this known device therefore relies upon the skill and manual dexterity of the operator in order to achieve correct alignment of the label and the compact disc. Moreover, the device is reliant upon the operator being sufficiently well-organized to keep the two components in close proximity ready for use.
Accordingly, it is an object of the present invention to provide a device that overcomes the aforementioned problems and is inexpensive to produce, manually operable, permits reliable alignment of the label and the compact disc, and substantially eliminates the opportunity for operator error.
SUMMARY OF THE INVENTION
The present invention, in a first embodiment, is directed to a unitary device for applying a first substantially planar member having a central aperture of a first diameter to a second substantially planar member having a central aperture of a second diameter. The device includes: an assembly having a circumferential flange with an upper flange surface capable of supporting the first planar member; a piston member having an upper surface; a first rod having a diameter slightly less than the first diameter, extending from the upper surface of the piston member; and a second rod having a diameter slightly less than the second diameter, extending from the first rod. The first diameter is greater than the second diameter. The piston member is adapted to move from a first upward position in which the second rod and at least a portion of the first rod extend above the upper flange surface to a second lower position in which at least the first rod is entirely below, or is level with the upper flange surface so that the first and second members are pressed against each other.
The first and second members can be reliably retained with their respective central apertures in concentric alignment. By moving the piston from first to second positions, the first and second member can be brought together with their alignment maintained. By virtue of the first rod having a substantially similar diameter to the aperture of the first member, the first member can be retained in position on the flange by means of the first rod extending through its aperture. Similarly, the second rod, having a diameter substantially similar to the aperture of the second member, is able to retain the second member in position.
The device may further comprise a tube having an upper end and a lower end. The circumferential flange extends from the upper end of the tube, and the piston member is slidably received in the tube.
A further aspect of the present invention is a compact disc label capable of allowing visual inspection of the disc surface underneath the label. More particularly, the present invention comprises a transparent compact disc label.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded view of one embodiment of the inventive device, illustrating the components of the device, as well as the first and second planar members; and
FIG. 2 is a perspective view of the assembled device of FIG. 1 with the first and second planar members in position to be placed on the device.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, the present invention comprises a top cover plate 7 having a central hole 6, a hollow structure, preferably a cylinder 8, and a bottom plate 9. The top plate 7 is affixed to structure 8 such that the structure and central hole 6 are concentrically aligned. In this preferred embodiment, bottom plate 9 is affixed to the lower opening of structure 8. The top plate 7, structure 8 and bottom plate 9 form an enclosed container 21. The container 21 houses the piston assembly. The piston assembly includes a piston 5, a first rod 4, and a second rod 3. The first rod 4 has a concentric outer diameter larger than the diameter of second rod 3. The first rod 4 is connected to second rod 3 and is preferably integral with second rod 3. The second rod 3 extends upwardly above top plate 7. The meeting of second rod 3 to first rod 4 forms a shoulder 14. The piston 5 is free to travel upwardly and downward within container 21.
The preferred embodiment of the present invention illustrated in FIG. 1 includes a spring 11 housed within container 21, between bottom plate 9 and piston 5. The spring 11 ensures that piston 5 rests in a fully upward position such that second rod 3 and first rod 4 protrude upwardly through center hole 6 in top plate 7. Ideally, piston 5 is prevented from being withdrawn from the upper end of structure 8. To prevent piston 5 from being withdrawn from structure 8, a collar (not shown) can be provided on the interior of structure 8 at its upper end. More preferably, top plate 7 can extend beyond the interior diameter of structure 8. As shown in FIG. 1, piston 5 has a diameter larger than the diameter of center hole 6 such that during normal operation the piston cannot be removed from the enclosed container 21. In the preferred embodiment the bottom plate 9 has pressure means 10 to provide an, outlet for pressure that may from within the container 21 as a result of movement of piston 5.
The structure 8, as shown in FIG. 1, preferably is a cylinder or tube. However, structure 8 can be any configuration that permits piston 5, along with first and second rods 4, 3, respectively, and spring 11 to move therein free of friction. Accordingly, piston 5, first and second rods 4, 3, respectively, and spring 11 can be any configuration compatible with the interior of structure 8. As shown, structure 8 is cylindrical and is compatible with coiled spring 11 and cylindrical piston 5 and first and second rods 4, 3, respectively.
As shown in FIG. 2, the present invention is used to apply labels to CD ROMs as follows: a label 2 is placed onto top plate 7 with its adhesive side facing upwardly such that second rod 3 and first rod 4 protrude through the center hole of the label. The center hole of a CD ROM 1 is then placed onto second rod 3 with the side to be labeled facing downward toward the adhesive side of label 2 which is resting on top plate 7. The CD ROM 1 is prevented from coming into casual contact with the adhesive side of label 2 because first rod 4 has a diameter that is greater than the diameter of the center hole of the CD ROM.
Gentle downward pressure is applied to second rod 3 to depress piston 5 within container 21 against the action of compression spring 11. The piston 5 is gently deflected downward until the point at which first rod 4 is fully retracted into structure 8. At this point, the CD ROM 1 comes into contact with the adhesive side of label 2. The downward pressure is then gradually released allowing spring 11 to return piston 5 to its resting position making it easy for the user to remove the now labeled CD ROM 1.
In a preferred embodiment, second rod 3 has a diameter of 14 millimeters ±0.5 millimeters, and first rod 4 has a diameter of 41 millimeters ±0.5 millimeters. The top cover 7 has an outer diameter of about 118 to about 120 millimeters. The diameter of central hole 6 is about 41 millimeters plus sufficient clearance to allow passage of first rod 4 through central hole 6. The diameter of bottom plate 9 can be any diameter that permits the device to withstand the pressing operation of securing label 2 to CD ROM 1, and does not allow the device to fall over. For ease of manufacturing, the diameter of bottom plate 9 is approximately the same as that of top plate 7.
The structure 8 has an outside diameter of about 51 millimeters, and an inner diameter of approximately 44 millimeters. The spring 11, which must move frictionlessly in structure 8, has a diameter of about 40 millimeters. The diameter of piston 5, which must move frictionlessly in structure 8, is about 43 millimeters. The diameters of second rod 3 and first rod 4 approximate the diameter of the central aperture of a standard CD ROM, and the diameter of the central aperture of label 2, respectively.
In order to prevent pressure build-up within structure 8 when the piston 5 is depressed, bottom plate 9 can be provided with a pressure release 10. For example, pressure release 10 can be in the form of a hole, to allow air to escape from structure 8. The pressure release 10 can also be provided elsewhere on the device, such as in the wall of structure 8.
For both ease of manufacture and aesthetic purposes, the shape and size of top plate 7 can be identical to that of bottom plate 9. In order not to negate the usefulness of pressure release 10, the underside of the bottom plate 9 can be provided with a plurality of feet to raise the bottom plate from the work surface on which the device is placed. The use of feet can also help reduce the possibility of the device scratching or otherwise damaging the work surface.
The top plate 7 has an upper surface capable of supporting label 2. To achieve this, it is especially advantageous that central hole 6 has a diameter that approximates that of the center hole of label 2. Also, the outer diameter of the upper surface of top plate 7 should be the same or greater than the diameter of label 2. Furthermore, while the upper surface of top plate 7 may be slightly concave, a substantially planar surface is preferred since, when used to apply adhesive labels to compact discs, the planar surface reduces bubble formation and minimizes the flexing of the compact disc. While top plate 7 may have a circular outer radius, this is not essential and other shapes, as may be appropriate to the shape of the planar member to be supported, can be provided.
The second rod 3 extends concentrically from first rod 4. Since second rod 3 is of a smaller diameter than first rod 4, shoulder portion 14 is created where the two rods are joined. The shoulder portion 14 at least partially supports CD ROM 1. Because second rod 3 extends for a length or height greater than the thickness of CD ROM 1, the second rod can also function as a means for depressing piston 5 into cylinder 8. Thus, there is no need for an additional handle or grip means.
The piston 5, second rod 3, and first rod 4 can be joined to each other by any conventional means, such as, for example, adhesive or screws. For ease of manufacture and strength, it is preferable to form piston 5 and first and second rods 4, 3, respectively, in one piece, such as by molding.
Another aspect of the present invention is directed to a method for applying label 2 to a disc, such as CD ROM 1, using the device previously described. The method according to the present invention is suitable for applying labels of varying shapes and sizes to discs. Where it is desired to incorporate as much information as possible on label 2, the label may extend to almost the outer edge of the disc. Alternatively, where the surface area needed to convey the information is not as great, label 2 may be of substantially smaller diameter than that of the disc.
Labels for use on compact discs, such as CD ROM 1, have heretofore been such that information printed on the surface the disc is obscured. This is disadvantageous in situations where it is desired to add information, but at the same time, retain access to the information already provided. Until now, it has been necessary to reproduce the original information together with the additional information on the label to be affixed. Such an operation is both time consuming and increases the chance of introducing errors into the original material.
Therefore, a further aspect of the present invention resides in a compact disc label capable of allowing visual inspection of the surface of CD ROM 1 underneath label 2. More particularly, the present invention comprises a transparent compact disc label.
Not all transparent materials are suitable for application to compact discs. Further, the adhesive used to adhere the label to the disc must be compatible with both CD ROM 1 and label 2. The label material and adhesive must be selected to avoid the bubbling and creasing of label 2 during application of the label to CD ROM 1. It is also important for any such label 2 to be printable by both inkjet and laser printers. According to one aspect of the invention, one side of label 2 is coated with a coating that can receive an inkjet dye or pigment without the dye or pigment smudging or rubbing off.
Advantageously, transparent compact disc label 2 according to the present invention comprises a transparent, flexible polymeric material having a coating of an acrylic-based adhesive on at least one surface. The polymeric material may be a polyester or the like.
While the invention has been described in relation to the fixing of labels onto compact discs, it will be understood that the device according to the invention can be applied to any similar situation where it is desired to concentrically align two or more substantially planar members. | A compact disc labeling device for manual application of a label to a compact disc includes an assembly having a circumferential flange with an upper flange surface, a piston, a first rod having a diameter approximately equal to the diameter of the label's central aperture and that extends from the upper surface of the piston, and a second rod having a diameter approximately equal to the diameter of the disc's central aperture and that extends from the first rod. In use, a label is placed on the flange with the first rod projecting through its central aperture and the disc positioned on the second rod through its central aperture. When the piston is moved from an upper first position to a lower second position, the disc is applied to the label. | 8 |
This application claims benefit of Provisional No. 60/227,472 filed Aug. 24, 2000.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention generally relates to an improved comfort device to be used with a nasal mask. In particular, the device is useful in combination with masks which are used for the treatment of respiratory conditions and assisted respiration. The invention assists in fitting the mask to the face as well.
2. General Background
Nasal masks are commonly used in the treatment of respiratory conditions and sleep disorders by delivering a flow of breathable gas to a patient to either assist the patient in respiration or to provide a therapeutic form of gas to the patient to treat sleep disorders such as obstructive sleep apnea. These nasal masks typically receive a gas through a supply line which delivers gas into a chamber formed by walls of the mask. The mask is generally a semi-rigid mask which has a face portion which covers at least the wearer's nostrils. Additionally, the mask may be a full face mask. The mask is normally secured to the wearer's head by straps. The straps are adjusted to pull the mask against the face with sufficient force to achieve a gas tight seal between the mask and the wearer's face. Gas is thus delivered to the mask and the wearer's nasal passages and/or mouth.
One of the problems that arises with the use of the mask is that in order for the straps to be tight, the mask is compressed against the wearer's face and may push unduly hard on the wearer's nose. Additionally, the mask may move around on the wearer's face. Thus, there has been provided a forehead support, which provides a support mechanism between the mask and the forehead. This forehead support prevents both the mask from pushing too strongly against the wearer's nose and/or facial region as well as minimize movement of the mask with the addition of a contact point between the mask and the wearer's head as well as minimize uncomfortable pressure points of the mask. Additionally, the forehead support may prevent the airflow tube from contacting the wearer's forehead or face.
FIG. 1 shows a general perspective view of a related art forehead support 10 . The forehead rest or support 10 is attached to an airflow tube 12 extending from the mask 14 . The mask 14 and forehead support 10 are shown with headgear 16 which secures the mask 14 to the head of a patient. As can be seen in FIG. 1, the headgear 16 loops through the forehead support 10 at loops 18 and 20 . This pulls the forehead support 10 against the forehead, thus creating a snugly fitted mask 14 and also provides a stabilizing member for the mask 14 .
FIG. 2 discloses the construction of the related art forehead support 10 . The forehead support 10 has pads 24 and 26 , a back side of which can be seen in greater detail in FIG. 10 . These pads 24 and 26 are the actual contact points of the forehead support 10 to the forehead. The support pads 24 and 26 are mounted to the bridge 32 . Arms 34 and 36 are secured to bridge 32 by an adjustable locking mechanism which is better illustrated in the figures below. The bridge 32 provides three purposes to the forehead support 10 . First, it acts as a securing means for pads 24 and 26 . Second, it has loops 18 and 20 which receive the optional headgear 16 shown in FIG. 1 . Finally, it receives arms 34 and 36 , which may be adjusted, as described below. The bridge 32 and arms 34 and 36 operate in a cantilever fashion and are made of a polymeric material, which may be easily molded. Additionally, arms 34 and 36 join together to create an annular space 38 to receive airflow tube 12 which is connected to a flow generator to generate breathable air or some type of therapeutic gas. Arms 34 and 36 create an operational hinge. The tube 12 is an axis of this hinge.
FIG. 3 is an exploded view of FIG. 2 and shows the forehead support 10 in greater detail. Bridge engaging pins 56 , 58 , 60 and 62 are shown in FIG. 3 . As will be more apparent in the figures below, these engaging pins provide for the adjustability of the forehead support 10 . Bridge 32 includes slots 76 , 78 , 82 , 84 , 86 , 88 and 90 (see FIG. 9) and a mirror set of slots on the upper portion of bridge 32 (not visible in FIG. 9) for selectively receiving pins 56 , 58 , 60 and 62 . These slots open to the forehead side of the bridge. Additionally, there is a space or recess at arms 34 and 36 shown on arm 34 as 64 . The purpose of this space 64 is so that the user may compress arm 34 and thus press pins 56 and 58 together by pressing on surfaces 66 and 68 . The purpose of the compression is to decrease the distance between pins 56 and 58 such that they may be selectively inserted and locked into the desired pair of slots on bridge 32 . The length of the pins 56 and 58 is such that even when the pins are pressed together, they do not clear the slots in the bridge sufficiently to allow the arms to be dissasembled from the bridge without further action.
FIG. 4 is a side view of the mask 14 and forehead support 10 . The mask is shown as 14 with a dotted line showing the nose of a wearer 70 and the dotted line showing the forehead 72 of the wearer. Pad 26 is shown compressed by the forehead of the individual wearing the mask.
FIG. 5 is a top view of the forehead support 10 taken along lines 5 of FIG. 4 . Also, the mask 14 is not shown in FIG. 5 . This figure illustrates the forehead support 10 in a position wherein the forehead support is in the closest position to the tube 12 (shown as merely a space in FIGS. 5 - 6 ). The bridge 32 is shown essentially in contact with tube 12 . The pins 56 , 58 , 60 and 62 are shown in their furthest position from the center of the bridge 32 , engaging slot pairs 88 and 90 . This position may be utilized by someone with a large, protruding or bulbous forehead, or a high nasal bridge, or someone who prefers the airflow tube to be snug against their forehead. FIG. 6 shows the same forehead support in the next position, wherein the bridge 32 is moved away from tube 12 such that there is a gap 74 between bridge 32 and tube 12 . Here, pins 56 , 58 , 60 and 62 engage slot pairs 76 and 86 . As is visible from the figure, the forehead support 10 is now moved away from tube 12 , and is positioned differently than in FIG. 5 . This may be configured to fit someone with a less protruding forehead, or someone who wants the flexible tube further from their head than is possible in FIG. 5 . FIGS. 7 and 8 show the third and fourth position for the forehead support.
The related art arm 34 is shown in greater detail in FIGS. 11-13. As can be seen in the top view of the arm 34 shown in FIG. 11, the arm 34 includes a semicircular portion 100 , on an interior of which the annular space 38 is situated. An extending portion 102 extends from the semicircular portion 100 . Surfaces 66 and 68 , space 64 and engaging pins 56 and 58 are positioned on the extending portion 102 . Each surface 66 and 68 includes a generally oval depression 106 and 108 , respectively, positioned near the pins 56 and 58 . These oval depressions 106 and 108 can be felt by the wearer of the mask and assist the wearer in properly positioning his or her fingers near the pins 56 and 58 when it is desired to adjust the forehead support. This is especially important when the mask and forehead support are positioned on the wearer's head because at such time, the wearer cannot easily see where to place his or her fingers to adjust the forehead support. The oval depressions not only assist the wearer in properly positioning his or her fingers for adjusting the support, by virtue of the fingers engaging the depressions, the depressions also help maintain the fingers in the appropriate position.
FIG. 12 is a side view of the arm shown in FIG. 11 . As can be seen there, the semicircular portion 100 only extends upward to half of the height of the arm 34 . Because of this, the arm 34 is reversible, i.e., it can be flipped over, and then can be used as arm 36 . Thus, only one arm design need be molded and this can be used as both arm 34 and arm 36 , depending on its orientation. Extending portion 102 includes two horizontal flanges 110 and 112 connected by an intermediate web 114 . The two horizontal flanges are thicker in the horizontal direction and thinner in the vertical direction than web 114 . The space 64 is positioned on web 114 . The force required to press the pins 56 and 58 together is a function of the amount of material of the extending portion 102 on either side of the space 64 in the vertical direction, the length space 64 extends along portion 102 (i.e., the length of each cantilever arm on either side of space 64 ) and the type of material from which the arm 34 is constructed. These arms have been constructed of a polycarbonate, specifically, Makrolon 2458 manufactured by Bayer.
FIG. 13 shows a cross-section of the arm 34 along line 13 — 13 in FIG. 12 . The comparative thicknesses of the flange 112 and the web 114 in the horizontal direction can best be seen here. The hatched portion of the arm 34 is the portion of the web 114 beyond the extended length of the space 64 .
It has been found that while the related art forehead support performs correctly if operated according to the instructions, an improvement can be made to reduce the risk of breakage when the forehead support is operated in a manner contrary to instructions.
Further, because depressions 106 and 108 are relatively narrow, an improvement can be made to allow the user to positively and firmly position his or her fingers to press the pins 56 and 58 together. Finally, because there is a relatively large amount of material contact between an interior of semicircular portion 100 and an exterior of airflow tube 12 , this can result in a relatively large amount of friction between the arm 34 and the tube 12 , thereby requiring additional force to pivot the arm 34 around the tube 12 for adjustment purposes.
SUMMARY OF THE INVENTION
The present invention is directed to an improved version of the type of forehead support discussed above. In particular, the present invention utilizes improved arms extending from the mask or gas supply line for adjustably engaging the bridge for allowing positioning of the mask on the face. First, extending portions of the arms are redesigned to compress more easily than the extending portions of the related art arms discussed above while at the same time maintaining the strength necessary for adequately supporting the airflow tube. Thus, the engaging pins may more easily be compressed together to allow for adjustment of the arms with respect to the bridge.
Furthermore, the extending portions of the arms are provided with locking portions that maintain alignment of the pins with respect to one another as they are being compressed to prevent lateral deflection of the pins, unintended stress loading on the arms and to allow easier engagement of the pins with the slots upon release of the extending portions.
Finally, arc portions of the arms that come into contact with the airflow tube 12 are undercut and radiused to prevent sticking or binding of the arms as they are pivoted about the airflow tube during adjustment of the forehead support, as compared to the related arm embodiment. Thus, the arms more easily pivot about the airflow tube during adjustment of the forehead support.
These improvements make it easier to adjust the forehead support, as well as make it easier to disassemble the arms from the bridge to allow thorough cleaning of the bridge and other support components.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a related art forehead support attached to a mask, headgear and a gas supply tube;
FIG. 2 is a perspective view of the forehead support of FIG. 1 removed from the mask and gas line;
FIG. 3 is an exploded view of the forehead support of FIG. 1;
FIG. 4 is a side view of the forehead support of FIG. 1 secured to a mask;
FIG. 5 is a top view of the forehead support of FIG. 1 in a first position;
FIG. 6 is a top view of the forehead support of FIG. 1 in a second position;
FIG. 7 is a top view of the forehead support of FIG. 1 in a third position;
FIG. 8 is a top view of the forehead support of FIG. 1 in a fourth position;
FIG. 9 is a front view of a bridge of the support of FIG. 1;
FIG. 10 is a single pad of the support of FIG. 1;
FIG. 11 is a top view of a of an arm for use in the forehead support of FIG. 2;
FIG. 12 is a side view of the arm of FIG. 11;
FIG. 13 is a section view of the arm of FIG. 12 along section line 13 — 13 ;
FIG. 14 is a top view of an improved arm for use in the forehead support of FIG. 2;
FIG. 15 is a side view of the arm of FIG. 14;
FIG. 16 is a section view of the arm of FIG. 15 along section line 16 — 16 ;
FIG. 17 is a perspective view of the arm of FIG. 11;
FIG. 18 is a partial section view of the arm of FIG. 13 along section line 18 — 18 ;
FIG. 19 is a partial section view of the arm of FIG. 15 along section line 19 — 19 ; and
FIG. 20 is a partial section view of the arm of FIG. 15 along section line 19 — 19 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 14 shows a top view of an improved embodiment of an arm for use with the present invention. Arm 200 includes a semicircular portion 202 and an extending portion 204 attached thereto. Semicircular portion 202 includes two arc portions 230 and 232 and an inner bore 234 . The two arc portions 230 and 232 are both recessed or undercut near their ends, as shown by the phantom lines 236 and 238 . Thus, the inner bore 234 is not perfectly circular in shape near the ends of arc portions 230 and 232 . Ends 240 and 242 of the arc portions 230 and 232 , respectively, are well radiused to prevent binding of the arm on the airflow tube during pivoting.
Extending portion 204 includes two flange portions 206 and 208 on which generally oval depressions 210 and 212 are respectively positioned. Bridge engagement pins 214 and 216 are positioned at far ends of flange portions 206 and 208 , respectively, and project, respectively, upwardly and downwardly from the arm 200 . A space 218 separates the flange portions 206 and 208 and in this embodiment, it can be seen that there is no vertical web between the respective flange portions and the space 218 . Also, it can be seen that the space 218 extends along a greater portion of arm 200 than does the embodiment shown in FIG. 12 . Thus, the cantilever arm portions of the arm of FIG. 14 are longer than the cantilever arm portions of the arm of FIG. 2 . Further, the cantilever arm portions of the arm of FIG. 14 are tapered along their length, such that the thickness of these portions is less near the pins than the semicircular portion 202 . Compare the thicker section of the arm of FIG. 15 shown in FIG. 19 with the thinner section of the arm taken nearer the pin 214 shown in FIG. 20 .
Even though the thickness of the cantilever arm portions of the arm of FIG. 15 have been reduced as compared to the arm of FIG. 2, the width of these portions has been increased with respect to the arm of FIG. 2 . Compare the widths of the arm of FIG. 15 shown in FIGS. 19 and 20 with the width of the arm of FIG. 13 shown in FIG. 18 . The increased width of the improved arm of FIG. 15 provides a stiffness in the lateral plane that is about 8 times greater than the stiffness of the arm of FIG. 2 . This increased stiffness prevents most accidental lateral deflections of the pins and would likely require a determined intentional action to laterally deflect the cantilever arm portions and pins.
A male locking portion 220 is positioned inboard of pin 214 and a female locking portion 222 is correspondingly positioned inboard of pin 216 . The male and female locking portions are configured so as to be able to fittingly mate with one another when the two flanges portions 206 and 208 are pressed together. As seen in FIG. 16, a section along line 16 — 16 in FIG. 15, the female locking portion can be configured as a chevron-shaped slot Correspondingly, the male locking portion 220 would be configured as a chevron-shaped projection to mate with the chevron-shaped slot of female locking portion 222 . The male and female locking portions can also have different shapes, as long as they will lockingly mate together when the two flange portions are pressed together. As with the arm 34 above, the arm 200 can be flipped over to provide the second arm of the forehead support and thus, only one mold is needed to cast both required arms.
The lengths of the pins 214 and 216 are provided such that when the pins are pressed together to the extent allowed by the locking portions, the pins will clear the slots in the bridge, contrary to the pins of the related art arms.
In a preferred embodiment, these improved arms are constructed of a polycarbonate, specifically, Makrolon 2858 manufactured by Bayer.
There are several advantages to this improved arm embodiment. First, because the space 218 extends farther along the arm 200 , the lack of a web between the flanges 206 and 208 and the tapering of the cantilever arm portions, it is as easy or easier to press the pins 214 and 216 together when adjusting the forehead support, even with the increased lateral strength of the improved arms. This is especially important because during the adjustment while the mask is on the wearer's head, the wearer cannot easily see the forehead support as he or she is performing the adjustment. The increased lateral strength helps resist accidental lateral deflection of the cantilever arm portions and pins, as well as providing a stronger support to the airflow tube. The end result is that at the outer portion of the arm 200 near the pins, the extending portion 204 has a greater stiffness and resistance to bending in the lateral or horizontal direction (i.e., the pivoting direction) than it does in the vertical direction (the non-pivoting direction). This is contrary to the embodiment shown in FIGS. 11-13 where the stiffness and resistance to bending is greater in the vertical direction than in the horizontal direction.
Of course, the taper, shape and/or the thickness of the cantilevered arm portions can be altered to vary the stiffness of the cantilevered arm portions in the horizontal or vertical directions, as circumstances warrant. Further, under certain circumstances, it is contemplated that the stiffness of the cantilevered arm portions in the vertical direction can be less, similar to, or even greater than the comparable stiffness of the cantilevered arm portions of the related art design in the vertical direction.
The use of the wider flanges also allows the use of broader oval depressions 210 and 212 . These broader depressions better accommodate the wearer's fingers and thus, give the wearer a more positive and more comfortable grip on the arms during adjustment.
The provision of the male and female locking portions assures that the two flange portions remained aligned with one another during the pressing together of the pins 214 and 216 . Thus, the pins are also maintained in alignment during compression, making it easier for both pins to align with their respective slots in the bridge during adjustment of the bridge. Without the locking mechanism, the pins can be twisted and splayed with respect to another during compression, making it more difficult to position the pins in the desired respective slots in the bridge during adjustment. Further, the locking portions also prevent the user from laterally deflecting the pins with respect to one another when disassembling the arm from the bridge. Since the pins are short enough to clear the slots in the bridge when pressed together, the arm need not be rotated or the pins laterally displaced from one another to allow the pins to clear the slots in the bridge. This reduces that the chance that a user can operate the arms contrary to instructions and thereby place undue stresses on the arms that could lead to premature failure of the arms.
Finally, the provision of the undercut or recessed portions 236 and 238 on arc portions 230 and 232 reduces the amount of material of the arm that comes into contact with the airflow tube 12 (or other pivot point). This helps prevent sticking or binding of the arm as it is pivoted about the airflow tube during adjustment of the forehead support, as compared to the related arm embodiment. The radiused ends 240 and 242 are also less likely to catch and hang up on imperfections in the airflow tube during pivoting, as compared to the sharper ends of the related arm embodiment. Thus, the arm 200 more easily pivots about the airflow tube during adjustment of the forehead support.
These improvements in arm 200 thus make it easier to adjust the forehead support, as well as make it easier to disassemble the arms from the bridge to allow thorough cleaning of the bridge and other support components. They also help prevent actions by the user contrary to instructions that could increase the risk of breakage of the forehead support.
While several improvements have been discussed above, it is contemplated that an improved forehead support according to the present invention need not utilize all such improvements but can utilize one or more of such improvements in various combinations.
It is to be understood that while the invention has been described above in conjunction with preferred specific embodiments, the description and examples are intended to illustrate and not limit the scope of the invention. | The present invention discloses an adjustable forehead support for a nasal or full-face mask wherein the forehead support may be adjusted for the different shapes and sizes of a facial profile. The forehead support utilizes a dual-arm system that adjusts the position of the forehead support vis-á-vis the mask and/or airflow tube. The angle of the mask to the face may be adjusted with the present invention. | 0 |
PRIORITY CLAIM
The present application is a National Phase entry of PCT Application No. PCT/EP2010/052418, filed Feb. 25, 2010, which claims priority from German Application Number 102009010537.9, filed Feb. 25, 2009, the disclosures of which are hereby incorporated by reference herein in their entirety.
FIELD OF THE INVENTION
The present invention relates to a beam combiner and a beam splitter.
BACKGROUND
A beam combiner is needed e.g. in a display device that can be fitted onto the head of a user, in order to be able to present to the user a generated image superimposed on the perceptible surroundings. The beam combiner is often formed as a curved spectacle lens in this case.
It is known to realize a beam combining through a semi-transparent mirror. However, the production technique is difficult, in particular if the light of the generated image is guided in the glass and the glass is curved.
Furthermore, a beam combining can be effected by means of an optical grating. However, this often disadvantageously involves undesired scattered light due to additional diffraction orders. Furthermore, such a grating is often only very narrow-band, with the result that the generated image can be only monochrome.
SUMMARY OF THE INVENTION
Starting from this, the object of the invention is to provide an improved beam combiner as well as an improved beam splitter.
According to the invention, the object is achieved by a beam combiner for combining a first ray beam with a second ray beam that does not run parallel to it to form a common ray beam, with a body that is transparent for the first ray beam and which has a superimposition area which the first ray beam strikes when passing through the body and which is divided into a first section and a second section, wherein only the first section, which is formed from a plurality of reflective and/or refractive deflecting elements spaced apart from each other, brings about a deflection of the second ray beam by reflection and/or refraction such that after leaving the body the first ray beam, together with the deflected second ray beam, forms the common ray beam.
Because of the deflecting elements which act reflectively and/or refractively, a beam combining can be realized for large wavelength ranges (in particular compared with conventional beam combiners by means of diffraction gratings).
The first section can have an imaging function for the second ray beam. Thus, not only is a desired beam combining carried out, but also equally imaging properties are realized by means of the first section. The imaging property of the first section can correspond to an imaginary optical effective surface which is curved and preferably has no mirror and rotational symmetry. The effective surface can also have no translational symmetry. Of course, it is also possible that the imaginary optical effective surface is rotationally symmetric (e.g. rotational asphere) or toric.
In particular, the surface of the first section, seen in top view onto the superimposition area, can preferably be 5 to 30% of the surface of the superimposition area. The proportion of the first section relative to the superimposition area can, however, also be 50% or more.
The deflecting elements can be formed at a material boundary surface (which can be flat or curved) of the body. A particularly simple manufacture is thus possible, e.g. by means of diamond milling. Furthermore, a production by moulding and casting methods is possible.
Each deflecting element can be formed flat. However, a curved formation of the individual deflecting elements is also possible.
In particular, all the deflecting elements can be formed identical. Alternatively, the formation of the deflecting elements can vary.
The deflecting elements are preferably irregularly distributed in the superimposition area, can be formed polygonal and/or have a maximum extent in the range of preferably 20-30 μm. The maximum extent can, however, also be 200 μm or 100 μm.
The beam combiner can be formed such that the part of the ray beam which strikes the first section is screened and thus does not become part of the common ray beam. Alternatively, it is also possible that the first section is transmissive for the first ray beam.
The first section can be formed in the manner of a discontinuous Fresnel structure. The Fresnel structure can have an imaging property that corresponds to the imaginary optical effective surface.
The reflective formation of the deflecting elements can be achieved by a reflective coating. The reflective coating can result in a complete reflection or also in a partial reflection. Furthermore, it is possible to realize the reflective action by total internal reflection. In this case, no reflective coating is needed.
The beam combiner can be formed in particular such that the second ray beam is guided in the transparent body to the superimposition area. This can take place for example by reflections at the material boundary surfaces. In particular, these can be total internal reflections.
Furthermore, in the case of the beam combiner according to the invention, the second section of the superimposition area can transmit the first ray beam.
The beam combiner can be used in a display device which has an image-generating module and a holding device that can be fitted onto the head of a user, wherein the beam combiner is attached to the holding device such that when the holding device is fitted a user can perceive the real surroundings through the superimposition area of the beam combiner, wherein the image-generating module generates an image and directs it as second ray beam onto the superimposition area such that when the holding device is fitted onto the head the user can perceive the image superimposed on the real surroundings.
In particular, the present invention also comprises such a display device with a beam combiner according to the invention. The display device can be called an HMD (Head-Mounted-Display) device. The display device can comprise further elements known to a person skilled in the art for the operation of the display device.
The display device can have e.g. the beam combiner according to the invention (optionally in one of its developments), an image-generating module and a holding device that can be fitted onto the head of a user and to which the beam combiner is attached such that when the holding device is fitted its user can perceive the real surroundings through the superimposition area of the beam combiner, wherein the image-generating module generates an image and directs it as second ray beam onto the superimposition area such that when the holding device is fitted onto the head the user can perceive the image superimposed on the real surroundings.
The beam combiner can have in particular an imaging property for the second ray beam.
Furthermore, the beam combiner can have a coupling-in area via which the second ray beam is coupled into the beam combiner and then guided in the beam combiner (for example by means of total internal reflections) to the superimposition area, wherein the coupling-in area is formed as a Fresnel surface which brings about a folding of the beam path.
The Fresnel surface preferably has an imaging property for the second ray beam. In particular, the Fresnel surface and/or the superimposition area can be formed at a curved material boundary surface of the beam combiner.
The Fresnel surface can be developed in particular in the same manner as the superimposition area of the beam combiner.
The beam combiner according to the invention can also be integrated for example in a helmet visor, in order that e.g. information can be projected to the wearer of the helmet via the superimposition area. Other applications of the beam combiner according to the invention are also possible. Thus, for example a window glass pane can be formed accordingly, in order to enable a projection of information in the manner according to the invention.
A beam splitter is furthermore provided for dividing a ray beam incident on the beam splitter into a first ray beam and a second ray beam that does not run parallel to it, wherein the beam splitter comprises a body that is transparent for the incident ray beam and which has a division area which the incident ray beam strikes and which is divided into a first section with a plurality of reflective and/or refractive deflecting elements spaced apart from each other and a second section, wherein the part of the incident ray beam transmitted by the division area forms the first ray beam and the part of the incident ray beam deflected at the deflecting elements by reflection and/or refraction forms the second ray beam. A division even of a very wide-band incident ray beam is possible with this beam splitter.
The deflecting elements can have an imaging function for the second ray beam, be formed flat or curved, be irregularly distributed over the division area and/or formed polygonal. The extent of each deflecting element can preferably lie in the range of 20-30 μm (but a maximum extent of up to 100 μm or up to 200 μm is also possible) and the surface of the first section can, seen in top view onto the division area, preferably lie in the range of 5-30% (however, 50% and more is also possible) of the surface of the division area.
The first section can be formed in the manner of a discontinuous Fresnel structure.
Furthermore, the beam splitter according to the invention can be developed in the same manner as the beam combiner according to the invention.
When the beam combiner according to the invention or the beam splitter according to the invention is used in an optical device, the superimposition area or the division area is preferably arranged, as far as possible, in a pupil of the optical system or as close as possible to a pupil of the optical system.
It is understood that the features mentioned above and those yet to be explained in the following are applicable, not only in the given combinations, but also in other combinations or singly, without departure from the scope of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is explained in further detail below by way of example using the attached drawings which also disclose features essential to the invention. There are shown in:
FIG. 1 is a schematic view of a display device with a beam combiner according to the invention;
FIG. 2 is a top view onto the superimposition area 9 of the beam combiner 1 from FIG. 1 ;
FIG. 3 is an enlarged sectional view along the section line B-B in FIG. 2 ;
FIG. 4 is an enlarged view of the detail C 1 from FIG. 3 ;
FIG. 5 is a schematic view to illustrate the arrangement of the deflecting elements;
FIG. 6 is a further schematic view to illustrate the arrangement of the deflecting elements;
FIG. 7 is an enlarged view of the detail C 2 from FIG. 3 ;
FIG. 8 is an enlarged view of the detail C 2 from FIG. 3 according to a first variant;
FIG. 9 is an enlarged view of the detail C 2 from FIG. 3 according to a further variant;
FIGS. 10-12 depict examples of further profile shapes for the deflecting elements 12 ;
FIG. 13 is a perspective view of a development of the multifunction glass 1 from FIG. 1 ;
FIG. 14 is an enlarged sectional view along the section line D-D in FIG. 13 ;
FIG. 15 is a perspective view of a further embodiment of the multifunction glass 1 from FIG. 1 ;
FIG. 16 is a perspective view of a further embodiment of the multifunction glass 1 from FIG. 1 ;
FIG. 17A is an enlarged sectional representation along the section line E-E in FIG. 16 ;
FIG. 17B is a variant of the sectional representation from FIG. 17A ;
FIG. 18A is a schematic side view of a further embodiment of the display device 2 according to the invention;
FIG. 18B is a perspective representation of the display device from FIG. 18A ;
FIG. 18C is a top view of the superimposition area 9 of the multifunction glass 1 from FIGS. 18A and 18B ;
FIG. 18D is a perspective representation of a further embodiment of the display device 2 according to the invention;
FIG. 18E is a perspective representation of a further embodiment of the display device 2 according to the invention;
FIG. 19 is a perspective view of a further embodiment of the multifunction glass 1 from FIG. 1 ;
FIG. 20 is a perspective view of a further embodiment of the multifunction glass 1 from FIG. 1 ;
FIG. 21 is a perspective view of a further embodiment of the multifunction glass 1 from FIG. 1 ;
FIG. 22 depicts a further embodiment of the beam combiner 1 according to the invention;
FIG. 23 is a development of the deflecting mirror 12 of the beam combiner according to the invention;
FIG. 24 is a schematic sectional view of a beam splitter 27 according to the invention;
FIG. 25 is a variant of the beam splitter from FIG. 24 , and
FIG. 26 is a further variant of the beam splitter from FIG. 24 .
DETAILED DESCRIPTION
In the embodiment shown in FIGS. 1 to 3 , the beam combiner 1 according to the invention is formed as a multifunction glass of a display device 2 which comprises a holding device 3 that can be fitted onto the head of a user in the form of a glasses frame, wherein only one side arm 4 is drawn in schematically in FIG. 1 .
The beam combiner 1 is attached to the holding device 3 such that when the holding device 3 is fitted onto the head it is arranged in the manner of a glasses lens in front of an eye A of the user. The user can perceive the surroundings through the beam combiner 1 .
The display device 2 furthermore comprises an image-generating module 5 with which an image is generated which is presented to the user of the display device 2 superimposed on the surroundings perceptible for the user through the multifunction glass 1 when the user is wearing the display device on his head.
For this, the multifunction glass 1 has a coupling-in section 7 on its underside 6 and a superimposition area 9 on its front 8 . As will be described in detail below, the superimposition area 9 transmits surrounding light US, without deflecting it. Furthermore, the superimposition area 9 directs light BS coming from the image-generating module 5 which is coupled via the coupling-in section 7 into the multifunction glass 1 and is guided in the latter by total internal reflection to the superimposition area 9 , in the direction of the eye A of the user such that the user can perceive the generated image as a virtual image superimposed on the surroundings.
As can be seen in particular from the top view in FIG. 2 , the superimposition area 9 is formed substantially circular and is divided into a first section 10 and a second section 11 , wherein the first section 10 serves to deflect the image ray beam BS coming from the image-generating module 5 and the second section 11 serves to transmit the surrounding ray beam US coming from the surroundings. The superimposition area 9 has a plurality of sub-sections S spaced apart from each other which are distributed at random in the superimposition area 9 in the embodiment described here.
As can be seen from the enlarged sectional representation along the line B-B of one of the sub-sections S in FIG. 3 , each sub-section S has a plurality of deflecting mirrors 12 spaced apart from each other which here extend perpendicular to the plane of drawing of FIG. 3 .
The areas between the deflecting mirrors 12 in the sub-sections S as well as the remaining areas of the superimposition area 9 alongside the sub-sections S together form the second section 11 . The first section 10 is formed of the deflecting mirrors 12 .
As can furthermore be seen from FIG. 3 , the superimposition area 9 and thus also the deflecting mirrors 12 are formed on the front 8 of the multifunction glass 1 . Although the front 8 is curved, the curvature is not shown in FIG. 3 , to simplify the representation. The deflecting mirrors 12 are tilted relative to the normal of the front 8 such that the part of the image ray beam BS which strikes the respective deflecting mirror 12 is deflected towards the eye A as image partial beam BS′. The remaining part of the image ray beam BS which does not strike the deflecting mirrors 12 is reflected and/or transmitted at the front 8 such that it is not perceptible for the user.
The part of the surrounding ray beam US which strikes the backs of the deflecting mirrors 12 (from the left in FIG. 3 ) is screened by the deflecting mirrors 12 such that the user cannot perceive this part. This part is therefore drawn in hatched in FIG. 3 . The remaining part of the surrounding ray beam US passes as surrounding partial beams US′ through the transmissive areas 13 between or alongside the deflecting mirrors 12 .
The superimposition area 9 thus brings about a superimposition of the part US′ of the surrounding ray beam US passing through the transmissive areas 13 which form the second section 11 with the part BS′ of the image ray beam BS reflected at the deflecting mirrors 12 to form a common ray beam GS. The user wearing the display device 2 on his head can thereby perceive the image generated by means of the image-generating module 5 superimposed on the surroundings.
In the schematic representation of FIG. 3 , the beams BS′ and US′ run parallel to each other. However, this need not be the case. Thus, a “through-mixing” of the beams BS′ and US′ takes place e.g. because of the curvature of the front.
The thus-formed beam combiner 1 has the advantage that it is very broad band compared with previous diffractive solutions.
The individual deflecting mirrors 12 may be arranged distributed irregularly over the superimposition area 9 , as is the case here on the basis of the sub-sections S distributed at random in the superimposition area 9 . Of course, e.g. the distance between neighbouring deflecting mirrors 12 can also vary. Any other distribution of the deflecting mirrors 12 in the superimposition area 9 is also possible. The surface portion of the deflecting mirrors 12 relative to the whole surface of the superimposition area 9 , seen in top view onto the superimposition area 9 , can lie e.g. in the range of 5-30%.
Of course, it is also possible that deflecting mirrors 12 are provided in the whole superimposition area. In this case, the surface proportion given above can be achieved if the b/a ratio lies in the range of from 3:1 to 20:1 ( FIG. 4 ). In all the described embodiments, the height h in one example lies in the range of 5-500 μm, in another example, in the range of 0.01-0.1 mm. A range of 0.05-0.3 mm and a range of 200-300 μm are used on other embodiments. A size of for example 20-30 μm has proved to be very advantageous for the parameter a.
The first section 10 in FIG. 2 can also be called a discontinuous Fresnel structure, because of the deflecting mirrors 12 arranged distributed on the basis of the distributed sub-sections. This Fresnel structure can be determined as follows. The initial assumption is the general surface function f(x,y) given below.
f
(
x
,
y
)
=
∑
i
=
0
N
∑
j
=
0
N
(
c
i
,
j
x
i
y
j
)
(
1
)
The surface function f(x,y) can in particular describe a curved surface. The curved surface can be formed rotationally symmetrical. For example, the surface function can describe a rotational asphere. However, it is also possible that it describes a surface which is curved and has no mirror and rotational symmetry. Such a surface can also be called a free-form surface. The free-form surface can preferably have no translational symmetry.
By predetermining a maximum groove depth h (here e.g. between 0.01 and 0.1 mm), the following actual profile function can be deduced as profile height taking into account the height z(x,y) of the front 8 of the multifunction glass.
Profile= z ( x,y )−modulo( f ( x,y ), h ) (2)
Here, modulo(f(x,y),h) describes the respective Fresnel proportion which increases from 0 to h and then drops back to 0 in one step. Thus, modulo(f(x,y),h) describes a triangular function for a right-angled triangle. The following continuous profile function, such as is shown schematically in FIG. 5 , is thus obtained.
Depending on the desired surface ratio of deflecting mirrors 12 to the whole superimposition area and the size and number of the sub-sections S, areas or sections of this profile function are substituted by the spherical radius of the front 8 of the multifunction glass, with the result that the Fresnel structure shown below in FIG. 6 results. Because of the schematic representation of only a small section of the front 8 , the spherical curvature of the front cannot be seen in this representation.
In the embodiment example described here, the following polynomial coefficients were used, wherein the first figure with the coefficient c stands in each case for the power x and the second figure for the power y, with the result that e.g. c21 is the coefficient before xxy. Any coefficients c not listed are 0.
c10
3.09E−02
c01
−5.69E−01
c11
−1.00E−04
c21
2.71E−05
c12
1.34E−05
c22
2.57E−06
c20
3.17E−03
c02
2.44E−03
c30
2.64E−05
c03
2.23E−05
The radius of the glasses lens to which the Fresnel structure is applied is 105.08 mm here.
In the embodiment described, the deflecting mirrors 12 are formed by a metallization V of the inclined sections, as can be seen in the enlarged view of the detail C 2 from FIG. 3 in FIG. 7 .
In FIG. 8 , a variant is shown in which the free area which is formed due to the incline of the deflecting mirror 12 relative to the front 8 of the multifunction glass 1 is filled to the front 8 with material 14 . The filling is preferably carried out such that a smooth, continuous front 8 is formed. In particular, the same material as for the multifunction glass 1 itself can be used as material 14 .
However, it is also possible to design the beam combiner 1 such that the deflection of the image ray beam BS takes place by total internal reflection, with the result that a metallization is no longer necessary, as is shown in FIG. 9 . In this case, the surrounding ray beam US is also transmitted by the deflecting elements 12 .
Of course, it is also possible to provide the deflecting elements 12 with a partial metallization, with the result that they function both reflectively for the image ray beam BS and transmissively for the surrounding ray beam US.
Furthermore, it is possible to form refractive deflecting elements instead of reflective deflecting elements. In this case, the superimposition area 9 is preferably formed on the inside 16 of the multifunction glass 1 .
In the embodiments described thus far, the profile shape of the deflecting elements 12 in the sectional representations shown was always linear. However, other profile shapes are also possible. Thus, the edges can be curved convexly in cross-section, as is indicated in FIG. 10 . The representation in FIG. 10 , and also in FIGS. 11 and 12 , corresponds to the representation from FIG. 5 , with the result that, starting from this profile shape, the spherical radius is still to be provided in areas instead of the profile course shown, in order to then arrive at the desired profile course in the sub-sections S. A concave edge curvature, as is indicated in FIG. 11 , can also be provided.
Any desired curvature can also be provided, as is indicated schematically in FIG. 12 .
A variant of the multifunction glass 1 from FIG. 1 is shown in FIG. 13 . In this variant, the image-generating module or the imaging system 5 is arranged at the upper rim 15 . The image ray beam BS emitted by the imaging system 5 is guided in the glass 1 by total internal reflection at the front 8 as well as the back 16 of the glass 1 to the superimposition area 9 in which, in the same manner as in FIG. 2 , a plurality of sub-sections S with the deflecting elements 12 are arranged.
In FIG. 14 , a section through such a sub-section S along the line D-D is schematically represented enlarged. On the basis of the superimposition of the image ray beam BS and the surrounding ray beam US, the desired common ray beam GS is generated, with the result that a user who is wearing glasses with such a multifunction glass 1 with his eye A positioned in the pupil area P which is spaced apart from the back 16 can perceive the surroundings with the image generated by the imaging system 5 superimposed.
In the embodiment shown in FIGS. 13 and 14 , as well as in all the embodiments described thus far, the superimposition area is formed in the front 8 . The deflecting mirrors 12 are formed integrally in the front 8 , with the result that the superimposition area 9 is part of the front 8 of the multifunction glass 1 .
In FIG. 15 , a further embodiment of the multifunction glass 1 is shown, wherein here, as also in the embodiments still to be described below, the same elements are given the same reference numbers and, to avoid unnecessary repetition, reference is made to the corresponding description above.
In the embodiment from FIG. 15 , the imaging system 5 is arranged at the back 16 of the multifunction glass or spaced apart from the back 16 , with the result that the image ray beam BS enters the glass 1 via the back 16 . The image ray beam BS is then guided via total internal reflection at the front and back 8 , 16 to an area 17 of the upper rim 15 . The area 17 is metallized, with the result that the image ray beam BS is reflected in the direction of the superimposition area 9 . Between the mirror area 17 and the superimposition area 9 the image ray beam BS is again guided by total internal reflection at the front and back 8 , 16 . The desired superimposition for generating the common ray beam GS takes place in the superimposition area 9 .
The surface of the mirror area 17 which brings about the reflection can be plano. However, any desired curvature is also possible. In particular, it can be curved and have no rotational or mirror symmetry. Furthermore, it can preferably also have no translational symmetry.
Although, in the embodiment from FIG. 16 , the imaging system 5 is again arranged on the back or spaced apart from the latter, such that the image ray beam BS enters the multifunction glass 1 via the back 16 , in the embodiment from FIG. 16 , the image ray beam BS runs directly to the front 8 in which a deflecting area 18 is formed. This deflecting area 18 has a plurality of deflecting mirrors 19 arranged next to each other which can extend essentially parallel to each other. The deflecting mirrors 19 run from the top to the bottom in the representation from FIG. 16 and are tilted relative to the front 8 . Unlike the deflecting mirrors 12 of the superimposition area, no spaces are provided between the individual deflecting mirrors 19 , with the result that the deflecting area 18 can also be called a Fresnel area or Fresnel surface 18 . The sectional view along the line E-E in FIG. 16 is shown in FIG. 17A . In cross-section, the deflecting mirrors 19 are linear and arranged at the curved base surface which here is the front 8 of the multifunction glass. The individual edges 19 ′ which connect the deflecting mirrors to each other are aligned parallel to each other. The original course of the front 8 here is also drawn in schematically.
In a variant (not shown) of the multifunction glass 1 from FIG. 16 , another Fresnel surface is provided on the front 8 or back 16 of the glass 1 between the deflecting area 18 and the superimposition area 9 for guiding the beam. This further Fresnel surface can be formed in the same manner as the deflecting area 18 or the superimposition area 9 .
In FIG. 17B , a variant of the profile from FIG. 17A is shown which differs essentially in that the edges 19 ′ which connect the deflecting mirrors 19 are no longer oriented parallel to each other in cross-section, but radially relative to the centre, not shown, of the front 8 .
In FIG. 18A , a schematic side view of a further embodiment of the display device 2 according to the invention is shown, wherein only the multifunction glass 1 , the image-generating module 5 , the eye position K and some examples of beam courses for the image ray beam BS and the common ray beam GS are drawn in. The corresponding perspective view of the display device 2 from FIG. 18A is represented in FIG. 18B .
As can be seen from the representation in FIGS. 18A and 18B , unlike in the embodiment from FIG. 16 , the deflecting area 18 is no longer arranged next to the superimposition area 9 , but above the superimposition area 9 .
The deflecting area 18 here is a coupling-in area or section via which the image of the image-generating module 5 is coupled into the multifunction glass 1 such that the image ray beam BS is guided to the superimposition or coupling-out area 9 by means of total internal reflections.
The multifunction glass 1 has a spherically curved, convex front 8 with a radius of 143.5 mm as well as a spherically curved, concave back 16 with a radius of curvature of 140.0 mm, wherein the thickness of the glasses lens is 3.5 mm and PMMA was used as material for the glasses lens.
The Fresnel structure of the deflecting area 18 can be given in the same manner as for the deflecting mirrors 12 according to the above Formula (2), wherein here the whole deflecting area 18 is formed as a continuous Fresnel surface (thus without a substitution of areas by the spherical front 8 ) and the following function is used as surface function f(x,y):
f ( x , y ) = ∑ i = 0 M ∑ j = 0 N ( c k ( i , j ) · x i · y j ) , ( 3 )
wherein k(i,j) is determined as follows
k
(
i
,
j
)
=
(
i
+
j
)
2
+
i
+
3
·
j
2
+
1.
(
4
)
The depth of the Fresnel structure or the Fresnel crimping in z-direction and thus the value for Δh here is 0.1 mm and the Fresnel polynomial coefficients read as follows:
i
j
k
Value
0
1
2
1.978676e+000
0
2
5
−1.683682e−001
0
3
9
6.583886e−003
0
4
14
−1.592897e−004
0
5
20
1.673948e−006
2
0
3
−1.260064e−002
2
1
7
−1.594787e−004
2
2
12
5.047552e−005
2
3
18
−1.124591e−006
2
4
25
−3.539047e−008
2
5
33
6.224301e−010
4
0
10
2.326468e−004
4
1
16
−2.256722e−005
4
3
31
2.658107e−008
All unnamed coefficients k(i, j) which are not listed in the above table are equal to 0.
The Fresnel structure for the coupling-out area 9 can also be described by means of Formulae (2) to (4). The corresponding Fresnel polynomial coefficients are given in the following table, wherein again all unnamed coefficients k(i, j) which are not listed in the table are equal to 0.
i
j
k
Value
0
1
2
3.889550e−001
0
2
5
−3.833425e−003
0
3
9
−2.736702e−007
0
4
14
1.935143e−006
0
5
20
9.627233e−007
2
0
3
−5.487613e−003
2
1
7
5.506765e−005
2
2
12
1.146413e−006
2
3
18
2.124906e−006
2
4
25
−7.838697e−008
2
5
33
−7.841081e−008
4
0
10
4.996870e−008
4
1
16
−5.316581e−007
4
3
31
−2.683089e−008
Also in the case of the Fresnel structure of the coupling-out area or section 9 , Δh is equal to 0.1 mm.
The position of the optical surfaces in the overall coordinate system of the pupil P of the eye A (the point of origin is at K) can be given as follows by reference to the direction of the coordinates x, y and z in FIG. 18A in each case relative to the surface in the immediately preceding row (the coordinates x, y and z drawn in FIG. 18A relate to the coordinate system of the pupil P which is used only for the description of the Fresnel structures of the coupling-in and coupling-out areas 18 and 9 in connection with FIG. 18A ):
Surface
x-coordinate [mm]
z-coordinate [mm]
Tilt angle about x-axis (°)
P
0.000
0.000
0.000
9
0.000
21.500
0.000
18
0.000
0.000
0.000
5
0.000
16.828
14.042
In the case of the coupling-in and coupling-out areas 18 and 9 , the position of the coordinate system is given, with regard to which the Fresnel surface is defined in the manner given above. In each case, values of 0 are therefore given for the surface 18 , as the coordinate systems for the surfaces 9 and 18 coincide. The position and size of the used aperture surface of the respective Fresnel surface, which corresponds to the coupling-in section 18 and to the coupling-out section 9 , are as follows with regard to the coordinate system peculiar to the surface:
Element
x-coordinate [mm]
y-coordinate [mm]
APX [mm]
APY [mm]
9
0.000
0.000
14.5
7.1
18
0.000
19.87
11.6
4.8
In this table, the width of the Fresnel structure in x-direction is given in the APX column and the width of the Fresnel structure in y-direction in the APY column. Furthermore, the distance of the coupling-out section 9 from the coupling-in section 18 is given. The distance from the eye pupil P to the glasses lens (back 16 ) here is 18 mm, wherein the field of vision is 20 ×4° for a diameter of 6 mm.
In order to avoid a regular arrangement or structure of the Fresnel sections in the case of the coupling-out area 9 , they can be arranged e.g. only in the rectangular sub-sections S ( FIG. 2 ). The sub-sections S can also be circular, as is shown in the schematic top view onto the, for example rectangular, coupling-out area 9 in FIG. 18C and which is assumed for the following description. Circular areas are fixed, the diameter of which can be determined as follows
D =√{square root over ((100 −T )/100/π)}· 2 · APX/N
Wherein T is the required transmission for the surrounding light in percent, N the number of the circles in x-direction and APX the aperture width in x-direction. The circles are initially arranged equidistant in a fixed grid with a grid spacing APX/N in x and y. The positions of the centres of the circles are then easily modified, by dicing the direction and length of the shift of the centres. The length is chosen here such that no overlapping effect occurs between neighbouring circles.
The following formulae can be applied as statistical functions for length and angle.
Statistical displacement length:
r =( APX/N/ 2 −D/ 2)· randf
Statistical displacement direction:
w =360· randf
Wherein randf provides a random value between 0 and 1. The modified position of the circles then results according to the following formulae:
x =( i/N )· APX+r ·cos( w )
y =( j/N )· APX+r ·sin( w )
M =round( APX/APX )
Wherein the round function rounds the criterion (APY/APX) up to whole numbers.
Of course, any other type of distribution of the Fresnel structure can also be chosen, wherein an irregular arrangement is preferably chosen.
Variants of the display device 2 according to FIGS. 18A and 18B are shown in FIGS. 18D and 18E . In the embodiment from FIG. 18D , the coupling-in section 18 is offset both laterally and vertically to the coupling-out section 9 . In the embodiment from FIG. 18E , a deflecting section 18 ′ which can be formed in the same manner as the coupling-in section 18 as a Fresnel structure (here as a reflective Fresnel structure) is formed on the front 8 between the coupling-in and the coupling-out section 18 and 9 . In particular, the deflecting section 18 ′ can, in addition to the folding of the beam path brought about by it, also have another imaging property (in an identical or similar manner to the coupling-in section 18 and optionally the coupling-out section 9 ).
The formation of the coupling-in and coupling-out sections 18 and 9 as well as optionally the deflecting section 18 ′ on the same side of the multifunction glass (here on the front 8 ) facilitates the production of the multifunction glass 1 .
A further variant of the multifunction glass 1 is shown in FIG. 19 . The image ray beam BS again enters the multifunction glass 1 from the back 16 , and is reflected at the front 8 by a Fresnel surface 20 in the direction of the upper rim 15 . The Fresnel surface 20 is in principle constructed in the same way as the Fresnel surface 18 in FIG. 16 . The alignment of the tilting of the deflecting mirrors of the Fresnel surface 20 is merely chosen such that the deflection shown in FIG. 19 takes place. After being deflected at the Fresnel surface 20 , the image ray beam BS is guided by means of total internal reflection at the back and front 16 , 8 to the mirror area 17 , reflected there and again guided by means of total internal reflection between the front and back 8 , 16 to the superimposition area 9 .
A variant of the multifunction glass from FIG. 19 is shown in FIG. 20 . In this variant, instead of the mirror area 17 , a further Fresnel surface 21 is formed which in principle has the same structure as the Fresnel surface 18 . The alignment of the deflecting mirrors of the Fresnel surface 21 is merely chosen such that the deflection of the image ray beam BS shown in FIG. 20 takes place.
A further embodiment of the multifunction glass 1 is shown in FIG. 21 . In this embodiment, the image ray beam BS from the imaging system 5 again enters the multifunction glass 1 from the back 16 , is reflected at the upper rim at a first deflecting area 22 in the direction of a second deflecting area 23 at the lower rim of the multifunction glass 1 , and reflected there in the direction of the superimposition area 9 . The guiding in the multifunction glass 1 again takes place by means of total internal reflection at the front and back 8 , 16 of the glass 1 . The deflecting areas 22 and 23 can be formed as metallized areas, as Fresnel surfaces or also as areas in which the deflection takes place by means of total internal reflection.
In FIG. 22 , a further embodiment of the beam combiner 1 according to the invention is shown in which the ray beams BS and US to be superimposed both strike the superimposition area 9 from the same side but at a different angle. As can be seen from the schematic representation in FIG. 22 , the superimposition area 9 is formed such that both ray beams BS and US are focussed in the same focus 24 .
A development of the deflecting mirror 12 is shown in FIG. 23 . In this development, the deflecting mirror 12 has two mirror edges 25 and 26 which are metallized. Thus, three ray beams can be superimposed with each other, namely two image ray beams BS 1 and BS 2 with the surrounding ray beam US, as can be seen in the schematic representation from FIG. 23 . Deflecting mirrors 12 with the two mirror edges 25 and 26 can be arranged in the same manner as the already described deflecting mirrors 12 of the above embodiments.
The previously described beam combiner 1 according to the invention can also be used as a beam splitter 27 . For this, the beam combiner 1 need merely be passed through in the opposite direction, thus e.g. in FIG. 3 impinged by a ray beam coming from the right. This is represented in FIG. 24 , which shows the basic structure of such a beam splitter 27 which is essentially the same as the structure of the beam combiner. If an incident ray beam 28 strikes the beam combiner 27 (here from right to left) and passes through a division area 29 , the part of the incident ray beam 27 which strikes the areas 30 (which correspond to the areas 13 in FIG. 3 ) of the division area 29 between the deflecting elements 31 (which correspond to the deflecting mirrors 12 in FIG. 3 ), is transmitted and forms a first ray beam 32 . The part of the incident ray beam 27 which strikes the deflecting elements 31 is reflected by the latter and forms a second ray beam 33 which does not run parallel to the first ray beam 32 . The deflecting elements 31 can be formed in the same manner as the deflecting elements 12 of the beam combiner 1 .
In FIG. 25 , a variant of the beam splitter 27 is shown in which the division area 29 is formed at the side which the incident ray beam 28 strikes. Furthermore, the deflecting elements 31 are formed and arranged such that the reflected part 27 is focussed onto a detector 35 . In addition to the beam splitting, a beam focussing is thus also brought about.
In FIG. 26 , a variant of the beam splitter 27 from FIG. 25 is shown in which the division area 29 is formed on the side at which the incident ray beam 28 leaves the beam splitter 27 again. Also in this embodiment, a focussing of the second ray beam 33 onto a detector 35 is brought about by means of the deflecting elements 31 which here preferably function refractively. | A beam combiner for combining a first beam cluster with a second beam cluster that is not parallel to the first, to form a common beam cluster. The beam combiner includes a transparent body for the first beam cluster, which has a superimposition region that is encountered by the first beam cluster as it passes through the body. The superimposition region is split into a first section and a second section. Only the first section formed from interspaced reflective and/or refractive deflection elements causes a deflection of the second beam cluster by reflection and/or refraction, such that the first beam cluster forms the common beam cluster with the deflected second beam cluster once it has left the body. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates to a transistorized step-to-impulse conversion circuit.
A differentiating circuit consisting of a resistor and a capacitor has been long used for converting a step waveform into an impulse waveform. However it is extremely difficult to produce by the present semiconductor technology the monolithic integrated circuits including capacitors with a high capacitance so that the integrated circuits including a differentiating circuit must be connected to an outside capacitor and consequently a desired miniaturization cannot be achieved.
To overcome these problems, there has been invented and demonstrated a method for producing impulses by utilizing the delay in transmission of the signal in a plurality of stages of amplifiers, but this method has inherent limitations in that the circuit is very complex in construction and requires a large power. There has been also invented and demonstrated an impulse generator utilizing excess minority-carrier charge in transistors, but in this type impulse generator it is difficult to fabricate the integrated impulse generator circuits, resistors having a high value are required and the operation is often adversely affected by noise.
SUMMARY OF THE INVENTION
In view of the above, one of the objects of the present invention is to provide a step-to-impulse conversion circuit which is very simple in construction.
Another object of the present invention is to provide a step-to-impulse conversion circuit in which when the input is zero no current flows through any of the circuit components so that the power consumption may be minimized.
A further object of the present invention is to provide a step-to-impulse conversion circuit which is immune to noise.
A further object of the present invention is to provide a step-to-impulse conversion circuit which may eliminate the use of capacitors so that the design and fabrication of monolithic integrated circuits may be much facilitated.
Briefly stated, to the above and other ends the present invention provides a step-to-impulse conversion circuit comprising a first transistor with the base connected to an input terminal, a second transistor to which is applied the signal from the emitter of said first transistor, a third transistor to which is applied the signal from the collector of said first transistor, a switching element responsive to the output signal from said third transistor for bypassing the emitter current from said first transistor, and an output terminal connected to said second transistor.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram of a first embodiment of a step-to-impulse conversion circuit in accordance with the present invention;
FIG. 2 is a diagram used for the explanation of the mode of operation thereof; and
FIG. 3 is a circuit diagram of a second embodiment.
Same reference numerals are used to designate similar parts throughout the figures.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIG. 1 there is shown a circuit diagram of a first embodiment of the present invention. A signal input terminal A is connected through a resistor 5 to the base of a transistor 1. The emitter of the transistor 1 is connected to the base of a transistor 2 while the collector of the transistor 1 is connected through resistors 6 and 7 to a positive bus line f. The junction between the resistors 6 and 7 is connected to the base of a transistor 3 with the emitter connected to the positive bus line f. The collector of the transistor 3 is connected through resistor 8 to the base of a transistor 4 whose emitter is connected to a negative bus line g and whose collector is connected to the base of a transistor 2. The emitter of the transistor 2 is connected to the negative bus line g while the collector is connected not only to a signal output terminal E but to the positive bus line f through a resistor 9. Terminals F and G are connected to positive and negative terminals, respectively, of a power supply.
Under the conditions that a DC voltage is impressed across the feed terminals F and G and that the potential at the terminal A is zero, all of the transistors 1, 2, 3, and 4 are OFF so that the potential at the terminal E equals the voltage of the power supply; that is, the voltage of the positive bus line f.
When the potential at the input terminal A rises momentarily at t 1 as shown in FIG. 2(a), the base current flows into the transistors 1 and 2, and at t 2 the collector current starts to flow. Part of the collector current of the transistor 1 becomes the base current of the transistor 3, and at t 3 the collector current of the transistor 3 flows. At t 4 the collector current flows into the transistor 4 to saturate it so that the collector-to-emitter voltage becomes substantially zero and consequently the emitter current from the transistor 1 flows into the collector of the transistor 4 instead of the base of the transistor 2.
Therefore at t 5 the collector current of the transistor 2 becomes zero after the minority carriers in the base region of the transistor 2 have disappeared.
The waveforms of the signals at a, b, c, d and e in FIG. 1 are shown in FIGS. 2(a), (b), (c), (d) and (e), respectively.
In practice the first embodiment may comprise
transistor 1,2SC828,
transistor 2,2SC828,
transistor 3,2SA564,
transistor 4,2SC828,
resistor 5,10 KΩ
resistor 6,5 KΩ
resistor 7,5 KΩ
resistor 8,10 KΩ and
resistor 9,5 KΩ.
the time interval from t 2 to t 5 is, in general, of the order of a few microseconds, and the higher the current gains of the transistors 2, 3 and 4 or the lower the cutoff frequency of these transistors, the longer the time interval from t 2 to t 5 becomes. This time interval may be also varied by changing the base current of each transistor.
From FIG. 2(e) it is seen that the step input signal is converted into the negative-going impulse (which may be not regarded as an impulse in the strict mathematical sense because it has a width of a few microseconds, but may be treated as an impulse when the signals to be handled are relatively low in frequency).
The positive-going impulse may be derived from the emitter of the transistor 2 or an inverter connected to the output terminal E.
In FIG. 3 there is shown a circuit diagram of the second embodiment of the present invention, wherein the emitter of the transistor 1 is connected with the negative bus line g through a thyristor 10 instead of the transistor 4 in the first embodiment, the emitter of the transistor 2 is connected through a resistor 13 to the negative bus line, and the output terminal E is connected to the emitter of the transistor 2. A resistor 12 is connected between the gate and cathode of the thyristor 10 in order to stabilize the operation of the thyristor 10, and in order to compensate a higher ON voltage of the thyristor 10 than an ON voltage of the transistor, a diode 11 is connected between the emitter of the transistor 1 and the base of the transistor 2.
The mode of operation of the second embodiment is substantially similar to that of the first embodiment except that the positive-going impulse is obtained because the output terminal E is connected to the emitter of the transistor 2.
As described above, the step-impulse conversion circuit in accordance with the present invention comprises a first transistor with the base connected to an input terminal, a second transistor to which is applied the signal from the emitter of the first transistor, a third transistor to which is applied the signal from the collector of the first transistor, a switching element such as a fourth transistor or a thyristor for bypassing the emitter current from the first transistor in response to the output signal from the third transistor, and the output signal being derived from the second transistor. | A step-to-impulse conversion circuit for converting a step input into an impulse output is disclosed which may eliminate the use of capacitors and comprises a combination of four transistors or three transistors, one thyristor and one diode with resistors so that the fabrication of monolithic integrated circuits may be much facilitated. | 7 |
FIELD OF THE INVENTION
[0001] The present invention concerns a disintegrator roll housing, whereby an insert is placed in an area, following the feed entry of the band as seen in the direction of rotation of the disintegrating drive shaft and further concerns a procedure for the modernization of an open-end spinning apparatus, whereby an insert of the disintegrator roll housing can be removed and subsequently replaced.
BACKGROUND OF THE INVENTION
[0002] Disintegrator roll housings are known in multitudinous designs within the state of the technology, including the spinning units SE7, SE8 and SE9 of a rotor based spinning machine “Autocoro” of W. Schlafhorst AG & Co., 41061 Mönchengladbach, DE. The disintegrator roll housings of these spinning units consist essentially of individual segments, which are placed on a carrier plate. The individual segments, which are set on this carrier plate, thus form the circumferential wall of the distintegrator housing, particularly in the zone between the fiber band feed equipment and the contamination separation opening of the disintegrator roll housing.
[0003] This type of construction of a disintegrator roll housing brings with it the disadvantage that, following the entry of the fiber band by a suction condition, which suction extends itself from the housing of the rotor to that of the disintegrator, a large volume of air is pulled in. That air, which is induced particularly in the area of the contamination separation opening, can only be controlled as to quantity by regulation of the suction of the spinning chamber. This apparatus has, however, the general disadvantage that, in reference to the actually required air, excessive air is continually fed into the disintegrator roll housing. The result of this is that the incoming air itself can lead to difficulties within the disintegrator roll housing. Large cross-sectional openings in the area of the air flow entering the disintegrator roll housing do not yield optimal contamination combing-out and removal conditions. Such excess air leads, for example, to entrained particle dissipation, since the air exits from the disintegrator roll housing in an uncontrolled manner and carries with it fibers, which aggregate in the area of the spinning machine. This action results in disturbances in the operation of the machine.
[0004] An unpublished application DE 102 24 589.4 describes a disintegrator roll housing, wherein the circumferentially disposed wall of the disintegrator roll housing is formed by an exchangeable insert placed between the contamination separation inlet and the exit opening for fibers. Thereby, it is intended that the contamination removal can be effected and made adaptable to various fibers. The disintegrator roll housings in accord with the state of the technology have the disadvantage that the contamination separation can vary as to quantity, however, the known inserts are not designed to bring about a conformation of the disintegrator roll housings to the varying loads. The result of this is that the known disintegrator roll housings cannot be made to suit different fiber materials and other spinning conditions. Further, with the conventional segments, the zone of the contamination separation is not designed, so that the disintegrator rolls are covered, particularly about their edges. Moreover, the size of the contamination separation openings can be changed only insufficiently to meet optimal requirements, and especially the location of the openings in relation to the fiber feed (feed opening in the disintegrator roll housing) cannot be altered.
SUMMARY OF THE INVENTION
[0005] Thus, a principal purpose of the present invention is to propose a disintegrator roll housing, which avoids the disadvantages of the state of the technology, as well as to propose an insert, which has the capability of adjusting the disintegrator roll housing during the operation of the disintegrator under different spinning conditions. A further purpose of the present invention is to propose a procedure to modernize the open-end spinning apparatuses, which now adhere to the state of the technology. Various features and advantages of the invention will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the invention.
[0006] The present purpose, in accord with the invention, is to be achieved by a disintegrator roll housing having an insert extending itself up to the area of the contaminant separation opening of the disintegrator roll housing. Further, when seen in the axial direction, in relation to the disintegrating roll, the insert forms at least partially the circumferential wall of the disintegrator roll housing in the area of the contamination separation opening. By the use of an invented insert, a disintegrator roll housing, in a simple way, can be made to accommodate itself to various spinning conditions. Further, a disintegrator roll housing now in accord with the state of the technology can be modernized by means of the procedure of the invented procedure.
[0007] The achievement of the invention is such that, the disintegrator roll housing can be designed, so that, in accord with the invention, the input of air into the disintegrator roll housing can be better controlled and further, the position of the inlet on the disintegrator roll housing where the air intake takes place is similarly optimized. Likewise, the air content within the disintegrator roll housing can be essentially improved with the control and positioning. An additional advantage arises in that, with the aid of the invention, existing slots between the disintegrator roll housing and the associated rolls, even in the area of the contamination separation inlet, can be blocked, so that an agglomeration of fibers at the slots can be avoided.
[0008] The invented insert has the advantage of fulfilling the function of the circumferential wall of the disintegrator roll housing, especially in the area of the contamination separation inlet, so that, even here, the edges of the disintegrator roll are covered. As to the circumferential wall of the disintegrator roll housing, only the part of the disintegrating roll is exposed, which is equipped with a processing surface. Advantageously, the disintegrator roll housing, following (in the direction of rotation of the disintegrator shaft) the contamination separation opening, possesses an abutment for the insert, so that the insert can be positioned in that area, where it comes into contact with the remaining components of the disintegrator roll housing.
[0009] In a particularly advantageous design, the disintegrator roll housing possesses a lateral limitation in the area of the contamination separation inlet, while the oppositely situated limitation of the contamination separation inlet is constructed at the insert. In this way, it becomes possible to exchange the insert, or to reset it anew, in the disintegrator roll housing, particularly in the axial direction of the roll. This permits an advantageous opening between the insert and the disintegrator roll housing.
[0010] The lengthening of the combing-out zone for the fiber band is advantageously achieved by a design of the fiber band support at the insert, whereby a joining of the fiber band feed to the disintegrator roll housing is carried out. Thereby, upon the disintegration of the fiber band, the quantity of contaminant is separated, and fiber is improved in its quality, that is to say, that fewer good fibers (in excess of 10 mm) are expelled, while the ejection of lighter contaminant is not adversely affected.
[0011] By the diminishing of the cross-sectional opening of the air intake at the suction point in the area of the contaminant separation, the velocity of the airflow is increased, which leads to a corresponding diminishing of the loss of good fibers. In this way, it is possible to disintegrate even fiber bands comprised of reclaimed material, which possess a high short fiber content and to work the corresponding fibers into yarns of high quality value.
[0012] By means of the invented design of the insert with at least one forked projection arrangement, the achievement attained is that, the circumferential wall of the disintegrator roll housing in the area of the contaminant separation opening can be constructed with the aid of the invented insert. By the formation of the forked insert, at the same time, the size of the contaminant separation agrees exactly in its width with the width of the active surface of the disintegration roll. In this way, the insert can possess two forklike projections, so that the left and the right limitation of the contaminant separation opening is formed by the insert.
[0013] In an additional advantageous design of the invention, the insert incorporates the contaminant separation opening, whereby even the area following the contaminant separation opening (“after” as seen in the direction of the motion of the fibers) can be located on the insert itself. This enables that even this area, for example, in the form of coatings or other geometrical formations can be optimally adapted to various spinning conditions. The area after the contamination separation suffers high abrasion, due to many types of fibers, so that an abrasive wear in this area need not lead to a situation in which the entire disintegration roll housing needs to be replaced. In accord with the invention, it would be sufficient simply to make a replacement with a new insert into the disintegrator roll housing.
[0014] In an especially advantageous development of the invention, the insert possesses rounded off edges in the area of the air inlet at the contamination separation opening, in order that the flow of incoming air, which occurs in this area, is assured of undisturbed flow in the greatest possible manner. It is particularly advantageous, if the insert is placed on the disintegrator roll housing with a capability of being exchanged, especially where fastening means are concerned.
[0015] The fastening means, for example, are in the form of bolt borings or the like. By means of the design, wherein the insert in the area of the contamination separation covers the edges of the disintegrator roll, the advantageous achievement is, that no fibers can migrate in this area too far outside of the surface prepared roll. In the case of a favorable formation, the forklike projections impinge on an abutment, whereby they lie on the disintegrator roll housing. In this way, an exact positioning of the insert is possible.
[0016] An achievement of the invented procedure is that an open-end spinning apparatus conforming to the state of the technology can be reworked in such a manner, so that the apparatus can be modernized Thereby, in the area of the contaminant separation, the open-end spinning apparatus possesses a controllable air inflow, as it does in the area following the feed of the fiber band. Simultaneously, it is possible to bring about positive effects on the quantity of the contaminant separation where the circumferential wall of the disintegrator roll housing is concerned, both before and after the contamination separation opening. Further advantageous embodiments of the invention are described in the subordinate claims or alternate independent claims.
[0017] The present invention is more completely explained with the aid of drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 shows a sectional presentation in profile of an invented disintegrator roll housing having an inset in accord with the invention;
[0019] FIG. 2 shows a top view of the insert of FIG. 1 and;
[0020] FIG. 3 shows a top view of an alternatively formed insert in accord with the invention.
DETAILED DESCRIPTION
[0021] Reference will now be made in detail to the presently preferred embodiments of the invention, one or more examples of which are shown in the figures. Each example is provided to explain the invention, and not as a limitation of the invention. In fact, features illustrated or described as part of one embodiment can be used with another embodiment to yield still a further embodiment. It is intended that the present invention cover such modifications and variations.
[0022] The sectional view of FIG. 1 illustrates a profile view of the invented disintegrator roll housing with an invented insert, wherein the disintegrator roll is absent from its casing. For the mounting of the disintegrator roll, the disintegrator roll housing 1 has a round opening 14 , through which passes, in operational conditions, a shaft, upon which the disintegrator roll is fastened. The disintegrator roll housing 1 has a feed opening 2 through which the fiber band (not shown) to be disintegrated is transported into the disintegrator casing 1 with the help of a feeding shaft 15 . The feeding shaft 15 operates in a conventional manner, coactively functioning with a charging trough 16 . The charging trough 16 confines the fiber band between itself and the feed shaft 15 by means of elastic elements 17 , so that between the fiber band and the feed shaft no slippage occurs and the fiber band can be controllably fed into the disintegrator roll housing 1 .
[0023] For the lateral guidance of the fiber band in the area of the charging trough 16 , this trough 16 possesses two limiting sides, through which the fiber band is guided in the area of the charging trough 16 , as seen in the axial direction of the feed shaft 15 . The direction of rotation of the disintegrator roll is designated by the arrow P. After the area of the limiting sides, the charging trough 16 connects to a still another fiber band support 162 , which, in this area likewise forms a part of the circumferential wall 11 of the disintegrator roll housing 1 . As seen in the direction of rotation P, following the charging trough 16 , the invented insert 5 is connected, which will be discussed later. In accord with each formation of the charging trough 16 , it is possible, at least partially, that the insert 5 can also include the fiber band support 162 .
[0024] After the insert 5 , in the circumferential direction of the arrow P, the disintegrator roll housing 1 has in addition a circumferential wall 11 , which finally transforms into an exit opening 3 , through which, in a known manner, the disengaged fibers are ejected from the disintegrator roll housing 1 , wherein the fibers are conducted to spinning mechanism, for example, an open-end spinning apparatus. The exit opening 3 connects into a fiber feed conduit 31 . Following the exit opening 3 , as seen in the direction of rotation P of the disintegrator roll, the disintegrator roll housing 1 is equipped with the circumferential wall 11 , which extends as far as the band feed opening 2 .
[0025] The insert 5 , which is located between the charging trough 16 and an abutment 41 of the disintegrator roll housing 1 , is exchangeably attached onto the side wall 18 of the disintegrator roll housing 1 by fasteners 6 , which may be bolts or through-pins. In the area between the charging trough 16 and insert 5 , there is to be found a small streamlined slot in the circumferential wall 11 of the disintegrator roll housing 1 , the cross-section of which is regulated by the necessary moveability of the charging trough 16 .
[0026] A contaminant separation opening 4 extends itself, as seen circumferentially, between the contamination separation wall 42 and the limiting wall 43 . This extent is indicated by the lines 44 . Between the two (separate) lines 44 , which represent the length of the contamination separation wall 42 as well as that of the limiting wall 43 , the insert 5 possesses the lateral border 12 , which limits the extent of the contamination separation opening 4 in the axial direction, back to the side wall 18 . Between the side limitation 12 and the opposite limitation 13 (see FIG. 2 ) as well as between the lines 44 , is to be found the contamination separation opening 4 .
[0027] Thus, the contamination separation opening 4 , in the embodiment of FIG. 1 , is designed as an opening in the insert 5 , since the insert 5 , both in its circumferential direction as well as in its axial direction, extends itself beyond the contamination separation opening 4 and, to a certain extent, also comprises part of the circumferential wall 11 of the disintegrator roll housing 1 . In the direction of the arrow P, and after the contamination separation opening 4 , the insert 5 possesses a contact surface 53 , which, in the embodiment shown in FIGS. 1, 2 , is not interrupted in the axial direction. This contact surface 53 strikes the abutment 41 of the disintegrator roll housing 1 .
[0028] Upon an exchange of the insert 5 , it is also possible that a determination can be made of both the size of the contamination separation opening 4 as well as its position in the circumferential direction of the circumferential wall 11 of the disintegrator roll housing 1 , since the contamination separation opening 4 is an integral component of the insert 5 . Principally, because the formation of the disintegrator roll housing 1 , that is to say, its circumferential wall 11 , determines the beginning of the insert 5 in the area of the charging trough 16 , the length of the insert in the circumferential direction finds it limit at the abutment 41 of the circumferential wall 11 of the disintegrator roll housing 1 . Between these two points, the position of the contamination separation opening 4 , as well as its size can be practically optionally determined, that is, made to conform to the existing requirements of spinning-technology.
[0029] FIG. 2 shows a top view of the insert 5 of FIG. 1 in a view marked by arrow D of FIG. 1 . When seen in axial direction, it is obvious from FIG. 2 , that the insert 5 possesses both the lateral limitation 12 as well as the opposite limitation 13 of the contamination separation opening 4 . Consideration can also be given to the fact, that the one lateral limitation 12 could be a part of the side wall 18 (see FIG. 1 ) of the disintegrator roll housing 1 . A formation of this kind, however, would sharply restrict the flexibility of the insert 5 .
[0030] The lateral limitations 12 and 13 of the contamination separation opening 4 form together a part of the circumferential wall 11 of the disintegrator roll housing 1 . With this arrangement, even in the position of the contamination separation opening 4 , the edge of the disintegrating roll is covered by the circumferential wall 11 . Thereby, only the circumference of the disintegrator roll, which is supplied with an operative surface, lies opposite to the contamination separation opening 4 . In this manner, an improved air inlet in the area of the contamination separation opening 4 is attained, so that contamination can be better separated out and the area of the edge of the disintegrator roll can be kept free of fiber accumulations.
[0031] In FIG. 2 , a presentation of the fastening means 6 is presented in dotted lines. The insert 5 can be secured to the side wall 18 of the disintegrator roll housing 1 with the aid of these fastening elements 6 . On the left side of the insert, as shown in FIG. 2 , can be seen the contact surface 53 as well as the outside of the contamination separation wall 42 . The limiting wall 43 is designated as an invisible edge by the use of the dotted lines 431 . FIG. 2 further makes plain, that the location of the contamination separation opening 4 is more or less freely chosen on the insert 5 . Likewise, the length of the contamination separation opening 4 in its circumferential direction is more or less freely chosen.
[0032] FIG. 3 shows a top view similar to FIG. 2 of an insert in accord with the invention, whereby, however, the insert 5 does not encompass the contamination separation 4 from all sides. The lateral limitations of the contamination separation 4 take from the insert 5 of FIG. 3 two forklike extensions 51 , which carry on their ends contact surfaces 53 , with which the insert 5 strikes on the abutment 41 (see FIG. 1 ) of the circumferential wall 11 . The fastening (not shown) of the insert 5 of FIG. 3 is carried out in the same manner as in insert 5 of FIGS. 1 and 2 .
[0033] With the embodiment of the insert 5 shown in FIG. 3 , the size of the contaminant separation opening is likewise determined. However, its exact position, in particular its position in the circumferential direction, is not exactly optional, since the one limitation of the contaminant separation opening 4 is fixed by means of the abutment 41 of the circumferential wall 11 of the disintegrator roll housing 1 . In many insert cases, however, the residual advantages of the formation of the invented insert 5 in accord with FIG. 3 are fully sufficient, and permit an advantageous suitability and shaping of the contaminant separation opening 4 of the disintegrator roll housing 1 . Especially where the modernization of the disintegration apparatuses of the machines of the state of the technology is concerned, this embodiment permits a favorable cost and rapid modernization even on machines, which cannot tolerate a stillstand of long duration. In that case, the segment, which forms the circumferential wall of the disintegrator roll housing 1 between the fiber feed opening 2 and the contaminant separation opening 4 is removed and replaced by the insert 5 .
[0034] In order that the intake flow of air in the area of the contaminant separation opening 4 can be held free of turbulence, the edges 52 of the projections 51 of the insert 5 are designed to be rounded off. This formation is also advantageous when applied to the insert 5 in accord with FIG. 2 .
[0035] It will be appreciated by those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope of the invention. It is intended that the present invention include such modifications and variations as come within the scope of the appended claims and their equivalents. | An exchangeable insert is proposed as auxiliary equipment for a housing of a disintegrating apparatus of an open-end spinning apparatus. The insert is adaptable, so that the disintegrator roll housing can be made to conform to various spinning conditions. In a partial zone, in accord with this proposition, the insert replaces a circumferential wall of the disintegrator roll housing, wherein the insert extends itself into to a zone of a contamination separation opening of the disintegrator roll housing. Its extension in the axial direction is so chosen, that it, at least partially, forms a portion of the circumferential wall of the disintegrator in the area of the contamination separation opening. | 3 |
FIELD
[0001] This invention relates to the chemical synthesis of graphene oxide. Specifically, as compared to prior art methods, the invention disclosed herein provides a simple, cost-effective method of providing relatively large and high quality graphene oxide materials while preventing the creation of toxic gasses and avoiding the use of H 3 PO 4 .
BACKGROUND
[0002] Fundamentally, graphene consists of a single layer of graphite (i.e., sp 2 hybridized carbon atoms). Graphene is approximately two hundred times stronger than steel, nearly one million times thinner than a human hair, and more conductive than copper. With such unique and beneficial physical properties, graphene, and in particular, high quality graphene, is desirable for use in various industries. For example, obtaining high quality graphene is of significant importance for electronic and photonic based applications. Currently, chemical vapor deposition method is the preferred route of manufacturing high quality graphene for these applications. Chemical vapor deposition, however, is expensive and cannot currently produce the quantities of graphene demanded for large-scale industrial applications at a reasonable cost.
[0003] Because of its unique and beneficial properties, significant research and development work has recently been undertaken to cost-effectively produce high quality graphene on a commercial scale. One such method considered that is capable of producing large quantities of graphene is chemical reduction of graphene oxide. The graphene created through reduction of graphene oxide has traditionally been of an inferior quality as compared with graphene produced through chemical vapor deposition due to defects (discussed below) that are created during the manufacturing process. Graphene produced through reduction of graphene oxide is currently used in developing new technologically advanced materials specifically in the areas of nanocomposites, functional coatings, paints and electrode materials for chemical and biological sensing and energy storage devices.
[0004] One of the most common methods of creating graphene oxide is through the chemical exfoliation of graphite (e.g., bulk graphite), which consists of a large number of graphene sheets held together by Van der Waals forces. One source of excellent, high quality pure bulk graphite is Sri Lankan vein graphite. Sri Lanka has a longstanding reputation for its high quality crystalline vein graphite with purity levels ranging from 80-99% carbon. Sri Lankan vein graphite is mined as lumps and is considered to have a high degree of crystalline perfection, excellent electrical and thermal conductivities, and superior cohesive energy as compared to other natural graphite materials.
[0005] In a traditional chemical exfoliation method, graphite is treated with a strong oxidizing agent to produce graphene oxide. One of the earliest recorded methods of synthesis of graphene oxide was by Brodie (1859). Brodie demonstrated the synthesis of graphene oxide by adding a portion of potassium chlorate to a slurry of graphite in fuming nitric acid. Subsequent studies by Staudenmaier (1898) improved upon Brodie's method by using concentrated sulfuric acid as well as fuming nitric acid and adding the potassium chlorate in multiple aliquots over the course of the reaction. Staudenmaier's alteration of Brodie's method helped the production of a highly oxidized graphene oxide in a single reaction vessel significantly more practical. Hummers (1958) further improved upon this method (see Hummers et al, 1958, herein “Hummer”). In Hummers's method, which is commonly used today, graphite is oxidized by treatment with KMnO 4 and NaNO 3 in concentrated H 2 SO 4 .
[0006] These traditional methods of producing graphene oxide are not devoid of flaws. While each of Brodie's, Staudenmaier's, and Hummers's methods can be used to create graphene oxide, each results in a graphene oxide structure that is less than ideal for the creation of high quality graphene through reduction on a commercial scale. More specifically, each of these methods results in significant defects in the graphene oxide chemical structure, defects which are not readily repairable during a subsequent reduction of graphene oxide to graphene. For example, defects can form in Hummers's method because oxidation of graphite with KMnO 4 results in the formation of manganate ester which will create a vicinal diol. If left unprotected, the vicinal diol may be oxidized to diketone, which leads to the formation of holes in the graphene basal plane. Such chemical defects in the resulting chemically converted graphene diminish the highly sought after electrical and mechanical properties as compared with pristine, high quality graphene. Further, each of these prior art methods involves the generation of one or more toxic gases, such as NO 2 , N 2 O 4 , and/or ClO 2 .
[0007] Recently an improved version of Hummers's method was disclosed by James Tour's group at Rice University (see US 2012/0129736 A1, herein “Tour”). This improved method excludes NaNO 3 , requires a higher amount of KMnO 4 and H 2 SO 4 , and also performs the reaction in a 9:1 mixture of H 2 SO 4 /H 3 PO 4 . According to Tour, this method does not generate toxic gasses and prevents excessive oxidation and defect (i.e., hole) formation in the resulting graphene oxide. Also according to Tour, it is the addition of H 3 PO 4 that helps to prevent defect formation, which can be caused by excessive oxidation in the graphene oxide structure. More recently Chen and co-workers (see Chen et al, “2013”, herein “Chen”) introduce a method without using H 3 PO 4 , but the oxidation method gives lower oxidation than the Tour's.
[0008] The use of H 3 PO 4 , however, is undesirable due to its cost and the increased complexity of the reaction method. Moreover, KMnO 4 is one of the strongest oxidants, especially in acidic media. Complete intercalation of graphite with concentrated H 2 SO 4 can be achieved with the assistance of KMnO 4 by forming graphite bisulfate (see Sorokina et al, 2005). Accordingly, the formation of graphite bisulfate gives reaction stability, so the role of NaNO 3 and/or H 3 PO 4 is unnecessary for the synthesis of graphene oxide (herein “GO”) using Hummers method. Accordingly, it would be beneficial to create a commercially viable method of creating high quality, highly oxidized graphene oxide (i.e., graphene oxide with fewer defects) from bulk graphite without the creation of toxic gasses or other toxic byproducts or the use of H 3 PO 4 .
SUMMARY
[0009] Disclosed herein is a novel approach to the chemical synthesis of graphene oxide from graphite using only H 2 SO 4 , KMnO 4 and H 2 O 2 and/or H 2 O as reagents for the synthesis. The method disclosed herein is scalable, cheaper, and safer than prior art methods. The chemically exfoliated graphene oxide created by the method disclosed herein has high solubility in both aqueous and polar organic solvents and can be casted into thin membranes as well as exfoliated into single to few layer graphene oxide structures with relatively large lateral dimensions as compared to structures created by prior art methods.
[0010] More specifically, this application discloses a modified chemical oxidation method that synthesizes graphene oxide from graphite using only of H 2 SO 4 , KMnO 4 and quenching with H 2 O 2 and/or H 2 O or ice. The method of the present invention uses no H 3 PO 4 , the central protecting reagent used in the method disclosed in Tour. It was surprisingly and unexpectedly discovered that, in the correct proportions, H 2 SO 4 , KMnO 4 , H 2 O 2 , and/or H 2 O alone could be used as reagents without H 3 PO 4 to create high quality graphene oxide from graphite. Before Applicants' invention it was believed that the use of H 3 PO 4 was essential in the creation of high quality graphene oxide from graphite in a toxic-fume free method.
[0011] Generally, in embodiments of the present invention, graphite is placed into a vessel where H 2 SO 4 is added. KMnO 4 is added to this H 2 SO 4 /graphite mixture, while stirring. The stirring is then continued for several hours and the reaction is quenched with ice, H 2 O, and/or ice and H 2 O 2 . The supernatant is then discarded, leaving a graphene oxide slurry. The remains are then washed several times starting with deionized water followed by a 1:2 water:HCl mixture to remove Mn 2+ ions and other impurities. Washing is then carried out one last time with ethanol and diethylether in order to obtain graphene oxide powder. The brown color solid material obtained after this step is then dried at room temperature under vacuum. The pilot scale process is also performed in this embodiment, in order to understand scalability of the reaction.
[0012] Alternatively, the graphene oxide slurry can be exfoliated by adding a portion of the graphene oxide slurry dropwise to an aqueous solution and then ultra-sonicating the aqueous solution/graphene oxide slurry. The ultra-sonicated mixture can be transferred to an appropriate substrate if desired. Once the graphene oxide has been dispersed in an aqueous solution, it yields monomolecular or substantially monomolecular sheets of graphene oxide. These sheets can then be reduced to obtain reduced graphene oxide, the graphene form.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is an X-ray Diffraction pattern obtained for a graphene oxide powder according to an example embodiment of the present invention
[0014] FIG. 2 is a Thermogravimetric Analysis spectrum obtained for a graphene oxide according to an example embodiment of the present invention
[0015] FIG. 3 is a Fourier Transform IR spectrum for a graphene oxide powder according to an example embodiment of the present invention
[0016] FIG. 4 are Raman spectra for graphene oxide
[0017] FIG. 5 is a Nuclear Magnetic Resonance (NMR) spectra for graphene oxide
[0018] FIG. 6 is an Atomic Force Microscopy image of a graphene oxide flake on a mica substrate
[0019] FIG. 7 shows TEM images for graphene oxide obtained on a lacey-carbon TEM grid and SAED pattern
[0020] FIG. 8 is an UV/VIS spectrum for highly-oxidized graphene oxide
DETAILED DESCRIPTION
[0021] The following description provides detailed embodiments of various implementations of the invention described herein. After reading this description, it will become apparent to one skilled in the art how to implement the invention in various alternative embodiments and alternative applications. However, although various embodiments of the present invention will be described herein, it is understood that these embodiments are presented by way of example only, and not limitation. As such, the detailed description of various alternative embodiments should not be construed to limit the scope or the breadth of the invention.
[0022] In an embodiment, approximately 1.5 g of natural high purity (>99%) vein graphite obtained from Bogala Graphite (GK) (Sri Lanka) was added to 1 00 ml of 0° C. H2504 (95-97%, Sigma-Aldrich, analytical grade). During this addition, the mixture was maintained at 0-10° C. and stirred. While stirring the mixture, about 5.4 g of KMnO 4 (99%, Lions Lab Chemicals, India, LR grade) was added at a reasonable rate (i.e., 2 g min −1 ). The temperature of the mixture was maintained at about 0-10° C. At this point, the reaction mixture appeared green in color. After adding the KMnO 4 the mixture was stirred for 12 hours at 0-10° C. and the colour of the mixture turned to dark brown. After stirring for 12 hours, the reaction mixture was quenched with a mixture of about 200 g of ice, 200 ml of H 2 O, and 1.5 ml of H 2 O 2 . At this step colour of the reaction mixture turned into yellow.
[0023] The supernatant was then carefully discarded leaving graphene oxide slurry. Next, the remaining graphene oxide slurry was washed with 400 ml of deionized water and then was washed with a 1:2 aqueous HCl solution. After that, to obtain graphene oxide powder, the remaining slurry was washed with 400 ml of ethanol and 400 ml of ether. The brown colour solid material obtained was dried at room temperature under vacuum.
[0024] In order to understand scalability of the reaction, a pilot scale process is also performed by using approximately 100 g of natural high purity (>99%) vein graphite with the same process. In an embodiment, the reaction time is increased up to 20 hours.
[0025] Alternatively, the graphene oxide slurries were then exfoliated by adding about 5 mg of the viscous graphene oxide slurries dropwise into about 200 ml of deionized water. These slurry/water mixtures were then placed into an ultra-sonication device (Grant, USA, 120 W, 150 Hz) for 20 minutes. The ultra-sonicated, graphene oxide slurry/water mixtures were then transferred dropwise onto a freshly cleaved mica sheet to obtain Atomic Force Microscopy image.
[0026] GRAPHENE OXIDE MEMBRANE CHARACTERIZATION
[0027] X-ray Diffraction, Thermo-gravimetric Analysis, Fourier Transform Infrared Spectroscopy, Nuclear Magnetic Resonance Spectroscopy, Raman Spectroscopy, Atomic Force Microscopy and Transmission Electron Microscopy measurements on the graphene oxide membranes produced in an embodiment confirm the structural and chemical changes that have taken place due to the oxidation process.
[0028] X-ray Diffraction Characterization
[0029] X-Ray Diffractometric (“XRD”) data were measured on a D8-Bruker AXS Diffractometer equipped with MBraun PSD position sensitive detector and the X-axis was restricted within a range (of 20) from 5° to 55°. FIG. 1 at (a) shows a representative XRD spectrum obtained from graphene oxide created according to an embodiment method of the present invention. FIG. 1 at (a) shows an interlayer spacing of 9.48±0.12 Å. The XRD interlayer spacing is proportional to the degree of oxidation. This in turn is related to the facility to exfoliate the GO into monolayer sheets, which on reduction can lead to monolayer graphene.
[0030] It should be noted that the interlayer spacing reported here is similar to the spacing reported through the use of the method disclosed in Tour. However, FIG. 1 at (b) illustrate XRD spectrum obtained from graphene oxide from pilot scale process, with an interlayer spacing of 9.59±0.12 Å confirming an extremely high degree of oxidation. A value that is this high has never been reported in the literature to date.
[0031] Thermogravimetric Analysis
[0032] Thermogravimetric analysis (“TGA”) was carried out on SDT Q600 analyzer equipped with a temperature compensated thermobalance under a high purity N2 purged environment with a gas flow rate of 100 ml/min. The sample was heated from 35° C. to 1000° C. with a rate of 5° C./min. FIG. 2 shows a TGA spectrum obtained for a graphene oxide created according to an embodiment method of the present invention. The TGA spectrum of FIG. 2 shows a significant weight loss between 130° C. to 220° C. This corresponds to the release of CO and CO 2 release from the most labile functional groups. The slower weight loss beyond that to 1000° C. can be attributed to the removal of more stable oxygen functionalities.
[0033] Fourier Transform Infrared Spectroscopy Characterization
[0034] In order to get a qualitative understanding of the available functional groups,
[0035] Fourier Transform Infrared Spectroscopy (“FTIR”) measurements were recorded on a Bruker NANCO Vertex 80 FTIR spectrometer equipped with attenuated total reflectance accessory. A representative FTIR spectrum is shown in FIG. 3 . The following functional groups were identified. The hydroxyl stretching band (3000-4000 cm −1 ). The peak at 1732 cm −1 was assigned as carbonyl C═O double bonds stretching vibration, the sharp and strong absorption at 1624 cm −1 assigned as the stretching mode of intercalated water molecules. C═C from unoxidized sp 2 CC bonds (1590-1620 cm −1 ), C—O vibrations and C—O—C (-epoxy-) vibration at 1200 cm −1 and below. The observed spectral peak positions are in very good agreement with published data on graphene using the method disclosed in Tour.
[0036] Raman Spectroscopy
[0037] Raman spectroscopy of samples, lab and pilot scale process was performed by a Renishaw InVia Raman Spectrometer using a 514.5 nm wavelength laser. The data were collected with an objective of 50 x, scanning the spectrometer from 100 cm −1 to 3500 cm −1 . Raman spectra of the two samples lab process and pilot scale process are shown in FIG. 4 at (a) and (b) respectively. Usually graphene oxide has two prominent peaks called D and G and lesser intense higher order peaks 2 D and S 3 . The G peak corresponds to the E2G phonon at the Brillouin zone centre and is observed at 1580 cm −1 for graphite. The G peak of lab processed sample is wider and blue-shifted to 1587 cm −1 confirming the higher order oxidation which is similar to the method disclosed in Tour. The D peak, which requires a defect for its activation, arises due to the breathing modes of sp 2 rings, is centered at 1352 cm −1 . However, the G peak position of pilot scale process sample remains at 1580 cm −1 and The D peak is centered at 1347 cm −1 due to extremely high oxidation which already observed as in XRD. The ratio I(D)/I(G) for these GO derived from other methods is normally around 1 or more, compared to 0.95 for the lab process and 0.94 for pilot scale process. The lower I(D)/I(g) ratio indicates that the relative number of defects in the sp 2 bonded graphene structure which arises in the current oxidation method is lower. Inter-defect distance (La) in disordered sp 2 carbons is can be calculated from the relation I(D)/I(G)=C′(λ) La 2 , with C′(514.5 nm)˜0.55 nm −2 . The values of L a for samples is around 1.3 nm.
[0038] Solid State 13 C Nuclear Magnetic Resonance (NMR) Spectroscopy
[0039] FIG. 5 illustrates solid state direct 13 C pulse NMR spectra for highly-oxidized graphene oxide. The 13 C NMR spectra were obtained at 50.3 MHz, with 10 kHz magic angle spinning, a 90° 13 C pulse, 40 ms FID and 20 second relaxation delay. In the 13 C NMR spectra, six peaks were observed at 62, 73, 87, 130, 159 and around 173 ppm are assigned to epoxides, alcohols, lactols, graphitic carbons, carboxylates, and ketones respectively. The NMR results also well exhibits the oxidation process and good agreement with the other methods reported.
[0040] Atomic Force Microscopy Image
[0041] One of the most important aspects of commercial viability of any graphene oxide creation methods is the ability to obtain single to few layer graphene oxide sheets with reasonable lateral dimensions. As described above, graphene oxide created using the method of the present invention was exfoliated and transferred onto a mica substrate for characterization using atomic force microscopy. FIG. 6 , shows an atomic force microscopy image (“AFM”) that confirms the creation of relatively large (approximately 5 microns×7.5 microns) sheet single to few layers of high quality graphene oxide. The lateral size of this sheet is much larger than the reported values obtained using Hummers's or Tour's methods. Importantly, the AFM image confirms that the graphene oxide sheets created by the methods of the present invention are high quality and, similar to the graphene oxide created by Tour's method, do not contain substantial defects.
[0042] Transmission Electron Microscopy and Selected Area Electron Diffraction (SAED)
[0043] FIG. 7 at (a) shows TEM image for mono/few layer highly-oxidized graphene oxide obtained on a lacey-carbon grid. The corresponding shows Selective Area Electron Diffraction (SAED) patterns for graphene oxide is shown in FIG. 7 at (b). The SAED pattern for graphene oxide prepared by the methods of the present disclosure indicates good crystallinity in the sp 2 bonded carbon plane and a more regular large carbon frame work.
[0044] Ultra Violet-Visible Light (UV-Vis) Spectroscopy
[0045] FIG. 8 shows the UV-Vis absorption spectrum for graphene oxide, at 0.1 mg ml −1 concentration. λ max value of the present disclosure is 231.6 nm, resulting from π-π* transitions of the aryl rings. This implies the presence of the largest undamaged conjugated graphitic domains within the graphene layers. Additionally, a small shoulder peak at around 300 nm is due to the normalized absorbance of n-π* transitions implying an increase in the relative population of C═O containing functional groups with respect to the sp 2 -conjugated domains.
[0046] The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles described herein can be applied to other embodiments without departing from the spirit or scope of the invention. Thus, it is to be understood that the description and drawings presented herein represent presently preferred embodiments of the invention and are therefore representative of the subject matter broadly contemplated by the present invention. It is further understood that the scope of the present invention fully encompasses other embodiments that may become obvious to those skilled in the art and that the scope of the present invention is accordingly limited by nothing other than the appended claims. | Graphene oxide is synthesized by chemical treatment of graphite using only H 2 SO 4 , KMnO 4 , H 2 O 2 and/or H 2 O as reagents. Graphene oxide films obtained using the method disclosed herein were characterized using various analytical techniques. These analytical techniques confirmed the creation of single to few layer graphene oxide with relatively large lateral size distribution using the method disclosed herein. | 2 |
TECHNICAL FIELD OF THE INVENTION
The invention relates to methods of making integrated circuits. More specifically it relates to methods of fabricating interconnect structures in semiconductor devices.
BACKGROUND OF THE INVENTION
The need for lower resistance and capacitance in interconnect dielectric films caused by the ever-increasing miniaturization of semiconductor devices has led to the use of copper to form interconnects and vias rather than aluminum. When those structures are formed from copper a dual damascene process is typically used, in view of the difficulty in dry etching copper.
As the line width of interconnects continues to decrease, additional measures must be taken to guarantee the reliability of damascene interconnects that include trenches and vias. Brain et. Al., “Low-k Interconnect Stack with a Novel Self-Aligned Via Patterning Process for 32 nm High Volume Manufacturing,” IITC2009, session 13.1 (pp. 249-251), discloses a hardmask process for making the tightest pitch layers in the interconnect stack, to enable production of Self-Aligned Vias (SAV). In this and other conventional dual damascene processes, the vias are first created in the ILD, followed by the trenches, and then the vias and trenches are lined with a metallic Cu barrier and then filled with bulk Cu, followed by planarization.
U.S. Pat. No. 7,067,919 discloses a damascene interconnect method in which a metal mask having a trench pattern is formed on an oxide film overlying an interconnect film. The via pattern is defined in a layer of photo resist overlying the metal mask, and the interconnect film is etched to form the vias. After via formation, the photo resist film is removed and the trenches are formed using the metal mask, followed by filling the trenches and vias with copper.
U.S. Pat. No. 7,524,752 discloses removing a metal mask after forming trenches and vias, filling the trenches and vias with metal, followed by chemical mechanical processing (CMP). Dimensional variation that could occur if the metal mask were removed by CMP after filling the trenches and vias is said to be reduced.
The present inventor has however found that these techniques have various problems. Low-k film is typically used for the interconnect dielectric layers, so as to reduce unwanted interlayer capacitance. On the other hand, a metal mask is used to form an opening such as a via or through hole or trench, in order for the feature to be self-aligned. However, when using metal mask to form fine patterns, there is a difference in the stresses between the low-k film and the metal mask, which causes strain at the interfaces between these layers, and which makes it difficult to obtain a desired pattern with a high degree of precision.
SUMMARY
The present invention provides novel methods for making semiconductor devices, in which a first pattern is formed in both a metal film and an underlying dielectric layer that overlie an insulator layer above a semiconductor substrate. A second pattern is formed in the insulator layer, the second pattern being defined at least in part by a first mask positioned above the metal film and the dielectric layer. The metal film is then removed, and the first pattern is transferred to the insulator layer using the dielectric layer as a second mask. The first pattern preferably extends into the insulator layer to a depth different than that of the second pattern in the insulator layer.
In preferred embodiments, the second pattern is defined by the overlapping profiles of the mask and the first pattern in the metal film. The first mask may comprise a patterned layer of photoresist.
The first pattern preferably comprises a series of elongated openings arranged generally parallel to one another, corresponding to trenches to be formed in the insulator layer. The second pattern preferably comprises an array of openings corresponding to vias to be formed through the insulator layer. In such embodiments the first pattern is transferred to the insulator layer as a series of trenches whose depth is less than the thickness of the insulator layer, and the second pattern is formed in the insulator layer as an array of vias that preferably pass entirely through the insulator layer.
The trenches and vias formed according to these embodiments of the invention are preferably then filled with copper by a damascene method.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects, features and advantages of the invention will become more apparent after reading the following detailed description of preferred embodiments of the invention, given with reference to the accompanying drawings, in which:
FIGS. 1A and 1B are cross-sectional and top views respectively, through a semiconductor device at a first stage of processing according to a preferred embodiment of the method according to the present invention;
FIGS. 2A and 2B are cross-sectional and top views respectively, through the semiconductor device of FIGS. 1A and 1B at a subsequent stage of processing;
FIGS. 3A and 3B are cross-sectional and top views respectively, through the semiconductor device of FIGS. 2A and 2B at a subsequent stage of processing;
FIGS. 4A and 4B are cross-sectional and top views respectively, through the semiconductor device of FIGS. 3A and 3B at a subsequent stage of processing;
FIGS. 5A and 5B are cross-sectional and top views respectively, through the semiconductor device of FIGS. 4A and 4B at a subsequent stage of processing;
FIGS. 6A and 6B are cross-sectional and top views respectively, through the semiconductor device of FIGS. 5A and 5B at a subsequent stage of processing;
FIG. 7A is a cross sectional view, through the semiconductor device of FIG. 6A at a subsequent stage of processing;
FIG. 7B is a cross sectional view, through the semiconductor device of FIG. 7A at a subsequent stage of processing;
FIG. 8 is an overall schematic cross sectional view of a semiconductor device according to an embodiment of the present invention;
FIGS. 9A through 9D show the chemical formulae of exemplary materials that may be utilized in preferred embodiments of the present invention;
FIG. 10 show the chemical formula of a further exemplary material that may be utilized in preferred embodiments of the present invention;
FIGS. 11A and 11B conceptually illustrate the improved dimensional tolerances that may be achieved by preferred embodiments of the present invention;
FIGS. 12A and 12B are pictures of experimental results corresponding to FIGS. 11A and 11B ; and
FIG. 13 illustrates measured etching selectivity of embodiments according to the invention in relation to a conventional technique.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The invention will be now described herein with reference to illustrative embodiments. Those skilled in the art will recognize that many alternative embodiments can be accomplished using the teachings of the present invention and that the invention is not limited to the embodiments illustrated for explanatory purposes.
In FIG. 1 a , an insulator layer 173 has been formed on a substrate 100 , and dielectric layer 175 is formed on the insulator layer 173 . Metal film 178 is formed on the dielectric layer 175 , and overlying metal film 178 is a photoresist tri-mask composed of photoresist layer 188 , SiARC layer 184 (Si-based Anti-Reflection Coating layer) or LTO (Low Temperature Silicon Oxide) and an organic layer 181 , which is preferably an organic planarization layer (OPL), which acts like an unexposed resist.
As can be seen in FIG. 1 b , photoresist layer 188 bears a trench pattern, with the openings in the pattern exposing the underlying SiARC layer 184 .
The semiconductor device beneath the interconnect layers described above is in this example a transistor 110 , which includes device isolation regions 106 , insulator layer 130 and contact holes 135 formed on a substrate 100 , such as silicon substrate. Another interconnect layer 160 including interconnect 165 may overlie the insulator layer 130 . Etch stop film 170 , for example a silicon and nitrogen-containing film, is formed on the interconnect layer 160 .
The insulator layer 173 is formed on the etch stop film 170 . Dielectric layer 175 and metal film 178 are formed in that order as a hard mask layer on the insulator layer 173 .
The insulator layer 173 may include a porous SiOCH material. SiO 2 is preferably used as the dielectric layer 175 , although SiC, SiN or SiCN may also be used to form the dielectric layer 175 . Metal film 178 may include TiN, TaN or WN. As it is desirable to remove this dielectric layer 175 selectively from the insulator layer 173 when forming a mask, the carbon content in the insulator layer 173 may be more than 40 atomic percent, as shown in the FIG. 13 .
Turning now to FIGS. 2A and 2B , Si-ARC layer 184 , OPL layer 181 , metal film 178 and dielectric layer 175 are dry-etched so as to expose the insulator layer 173 , through photo resist mask 188 . After removal of the residual tri-mask layers e.g. by ashing, the metal film 178 and underlying dielectric layer 175 now bear the pattern transferred from mask 188 , exposing the underlying insulator layer 173 through the trench openings (see FIG. 2B ).
When the metal film 178 includes TiN, TaN or WN, carbon fluoride-based gases, such as CF 4 /C 4 F 8 /Ar/N 2 /CO, are preferably utilized to etch the metal film 178 . According to the present embodiment, the dry-etching selectivity between the insulator layer 173 and the dielectric layer 175 can be controlled to be in a range from 5-20 by choosing the materials and the etching condition.
When the dielectric layer 175 is made of SiO 2 , the main etching gas for etching the dielectric layer will be selected from O 2 , N 2 , H 2 , N 2 /H 2 , NH 3 , CO and CO 2 . To avoid residual SiO, at least one additional gas selected from CHF 3 , CH 2 F 2 , C 4 F 8 , CHF 3 , CF 3 I, CF 4 and NF 3 is preferably added to the main etching gas. The ratio of additional gas to main gas may be 0-20 volume %, preferably 5-10 volume %. To obtain a high selectivity, O 2 /CH 2 F 2 is preferably used for this etching step. To reduce the damage to the insulator layer 173 , N 2 /CH 2 F 2 , N 2 /H 2 /CH 2 F 2 or CO 2 /CO/CH 2 F 2 is preferably used for this etching step.
When the dielectric layer 175 is made of SiC, SiN or SiCN, the same gases as for SiO 2 may be used. It is also possible to use etching gas selected from O 2 /C 4 F 8 , N 2 /C 4 F 8 , N 2 /H 2 /C 4 F 8 and CO 2 /CO/C 4 F 8 . C 4 F 8 as additional gas may be added in a quantity of 0-20 volume %. Ar may be added to generate plasma.
The etching chamber pressure is preferably set to about 6.7 Pa (50 mT) and the bias power is preferably set on source power of about 500 W and bias power of about 100 W, for example.
Next, as shown in FIGS. 3A and 3B , the via lithography is performed. A tri-layer via mask is composed of new OPL layer 182 formed on the metal film/mask 178 , new SiARC layer 185 and new resist film 189 . As shown in FIG. 3B , resist film 189 has openings defining a via pattern, exposing the underlying SiARC layer 185 . The broken lines in FIG. 3B show the location of the underlying trench openings in the metal mask 178 and dielectric layer 175 , from which it can be seen that the vias to be formed in the insulator layer 173 will be defined in part by photo resist mask 189 and in part by the trench hardmask 178 / 175 , which promotes self-alignment of the vias to the trenches.
The via tri-mask is then dry etched as described above in connection with the trench lithography. In this step, however, etching is continued to actually form the vias 190 extending through dielectric layer 173 and reaching etch stop layer 170 , as shown in FIG. 4A . After removal of the residual photo resist 189 , SiARC layer 185 and the OPL layer 182 by ashing, the plan view of FIG. 4B is again of metal film 178 , but now through its openings there can be seen the partially etched insulator layer 173 as well as the regions of etch stop layer 170 that are exposed at the bottom of the vias 190 .
At this stage of the process according to the present embodiment, the metal layer 178 is removed from the dielectric layer 175 by dry etching or wet etching, as shown in FIGS. 5A and 5B . The trench pattern that had been transferred to metal layer 178 is preserved in the dielectric layer 175 , as shown in FIG. 5B , but the trenches themselves are not yet formed in the insulator layer 173 .
Cl 2 may be used as an etching gas to remove the metal film 178 from the dielectric layer 175 , because it has good selectivity for the metal film when TiN is used for the metal film 178 . Alternatively or in addition, H 2 O 2 or a mixed solution of H 2 O 2 and an alkaline additive may be used as a wet etching solution when TiN is used for the metal film 178 .
Referring to FIGS. 6A and 6B , trenches 186 are then formed in the insulator layer 173 , using dielectric layer 175 as a mask. This etching serves also to remove the etch stop film 170 exposed at the bottoms of the vias 190 , to reveal the underlying interconnects 165 . Trenches 186 and vias 190 are thus aligned, as shown in FIG. 6B .
When the metal film 178 is etched by dry-etching, it is possible to perform the above-described process in the same dry-etching chamber, from the step of patterning the photoresist 188 through formation of the trenches in the insulator layer 173 . However, it is also possible to use equipment having multiple chambers through which the device is transported between the steps of patterning photoresist 188 and forming the trench pattern in insulator layer 173 .
After forming trenches 186 in the insulator layer 173 , a wet clean process may be performed using conventional cleaning solutions such as dilute hydrofluoric acid or an organic amine solution. Next, as shown in FIG. 7A , a barrier film 177 such as TaN is formed on the insulator layer 173 . Then, a layer 180 of a metal, preferably Cu, is formed by plating following seed metal PVD, for example, and excess metal film is removed by CMP, as shown in FIG. 7B .
FIG. 8 schematically depicts an overall semiconductor device as may be formed by the methods according to the present invention. A variety of interconnects 155 are depicted, each composed of at least one via 140 and at least one trench 150 formed in an insulator layer 173 . A next interconnect layer comprises etch stop layer 192 and insulator layer 194 formed on the insulator layer 173 (after forming the interconnects 155 ). Interconnect 196 is formed in the insulator layer 194 in the same way as the interconnect 155 . A semiconductor device having the multilayer interconnects illustrated in the FIG. 8 is formed by repeatedly forming interconnects as described above.
FIGS. 9A-9D illustrate examples of compounds that form porous materials that are well-suited for use as the insulator layers 173 , 194 , etc. These compounds are ring shaped organo-siloxanes. It is also possible to use MPS (Molecular Pore Silica), which is a material formed by mixing ring shaped organo-siloxane with a compound as illustrated in FIG. 10 . These technologies are disclosed for example in U.S. Published Patent Appln. No. 2010/0219512, the entirety of which is hereby expressly incorporated by reference.
FIG. 11A shows schematically and for purposes of comparison the effect when trenches 186 are formed with the metal film 178 still in place, as is conventional. FIG. 11B shows by contrast when the metal film 178 is removed prior to forming trenches 186 in insulator film 173 , as per various embodiments of the present invention. Low-k film such as porous SiOCH is usually used for the insulator layer 173 . The stress difference between metal film 178 and the insulator layer 173 becomes more critical as the pattern size is reduced. This stress difference causes pattern “wigging” or “flop over”, as shown in FIGS. 11A and 12A .
On the other hand, in the FIG. 11B , the metal mask 178 is removed before forming the trenches 186 in the insulator layer 173 , using only dielectric layer 175 as a mask. In this case, the pattern “wiggling” or “flop over” does not occur, even if the pattern size is reduced. FIG. 12B shows an example of these results. Fine trench patterns are formed without “wiggling” or “flop over.”
Additional advantages of these embodiments include that, as the metal mask 179 has not remained on the dielectric film mask 176 during etching the trenches 186 , the aspect ratio of the interconnect 155 is reduced when filling the metal into the via and trench by plating or PVD. This enables filling the trenches and vias with less chance of voids.
Furthermore, as a top corner of the dielectric layer 175 is rounded during the etching of trenches 186 , when forming the PVD barrier or seed films before copper plating, overhang at the top corner of the dielectric pattern is reduced. Conventional methods typically require a separate etching step to ensure this rounded shape at the top corner of the dielectric pattern, which damages the surface of the insulator layer 173 . The embodiments described above provide the desired contour without an extra etching step and hence without the attendant damage to the insulator layer 173 .
FIG. 13 shows results of the measured etching selectivity between the insulator layer 173 and the dielectric layer 175 or the metal film 178 as a function of the carbon content of the insulator layer 173 . In particular, the etching selectivity relationship between the insulator layer 173 and the metal film 178 is almost constant when changing the carbon contents in the insulator layer 173 . On the other hand, the carbon content of the insulator layer 173 significantly affects the etching selectivity between a silicon dioxide-containing dielectric layer 175 and the insulator layer 173 . To ensure an etching selectivity more than 5 between the insulator layer 173 and the dielectric layer 175 , a porous SiOCH material which includes more than 40 atomic % carbon is preferred for use as the insulator layer 173 .
The embodiments of the present invention were described above with reference to the drawings. However, these embodiments are illustrative of the present invention and it is possible to adopt various configurations other than those described above. | An improved method of forming a semiconductor device including an interconnect layer formed using multilayer hard mask comprising metal mask and dielectric mask is provided. To form the second opening pattern being aligned to the first pattern, after the multilayer hard mask is used at the first step, then the dielectric mask is used to form a damascene structure in an insulator layer at the second step followed by removing the metal mask. | 7 |
This is a division of application Ser. No. 07/488,547, filed Mar. 2, 1990 now U.S. Pat. No. 5,029,419.
BACKGROUND OF THE INVENTION
This invention relates to a method and a device for processing a steering wheel to remove burr from a synthetic resin cover body of the steering wheel after the cover body has been formed on a metallic steering wheel frame by using a metallic mold.
Up to now, burr has been generated at the cover body during the formation process of the cover body due to a parting line of a metallic mold by means of which a cover body made of synthetic resin material is formed on a steering wheel frame except a part thereof for connecting the steering wheel with a column shaft.
For this reason, work to remove burr was necessary after the forming process. However, the removal of burr had to be done only by handwork using cutting knives since the cover body is made of relatively soft synthetic resin material such as polyurethane. This was relatively costly and inefficient. Furthermore, different finishes were obtained according to the skill of the workers and uniform finishes would not be obtained whereby some steering wheels would be rejected due to mistakes of workers.
SUMMARY OF THE INVENTION
The principal object of this invention is to provide a method of processing steering wheels that is able to remove burr efficiently and provide uniform finish, and to protect from corrosion an exposed part of the frame of the steering wheel connecting with a column shaft, and to process a steering wheel at low cost.
The above and further objects and novel features of the invention will more fully appear from the following detailed description when the same is read in connection with the accompanying drawings. It is to be expressly understood, however that the drawings are for purpose of illustration only and are not intended as a definition of the limits of this invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a flow chart showing an embodiment of a method to process a steering wheel of this invention.
FIG. 2 is a plan view of a steering wheel to be processed.
FIG. 3 is a cross-sectional view taken on line 3--3 of FIG. 2.
FIG. 4 is a plan view of an embodiment of a processing device of a steering wheel of this invention.
FIG. 5 and FIG. 6 are front and side views, respectively, showing a shot blast apparatus which is used in the processing device of a steering wheel of this invention.
FIGS. 7 to 9 inclusive are explanatory views of a rotating apparatus for a supporting stand for a shot blast apparatus shown in FIG. 5 and FIG. 6.
FIG. 10 is an explanatory view of a refrigerant supplying machine of a shot blast apparatus shown in FIG. 5 and FIG. 6.
FIG. 11 is an explanatory view of a main part of a shot blast apparatus shown in FIG. 5 and FIG. 6.
FIG. 12 and FIG. 13 are cross-sectional views showing different embodiments of a drying apparatus which is used in processing of steering wheels.
FIG. 14 and FIG. 15, FIG. 16 and FIG. 17, are explanatory views showing different embodiments of a shot blast device of this invention, respectively.
DESCRIPTION OF PREFERRED EMBODIMENTS
This invention will be described in detail hereinafter with reference to the embodiments shown in the figures.
A steering wheel 1 shown in FIG. 2, which is used in a method of processing the steering wheel of this invention, comprises a steering wheel frame 1a made of metallic material and a cover body 1c which is formed from synthetic resin material such as polyurethane using a metallic mold so that the cover body 1c covers all of the steering wheel frame except the part 1b, as shown in FIG. 2 and FIG. 3, for installing the steering wheel onto a column shaft.
Burr 6 is generated along the parting line of the metallic mold during the forming process of the cover body 1c.
The steering wheel 1 having burr 6 is processed into a steering wheel 1B from which burr has been removed by the steering wheel processing method of this invention.
The steering wheel processing method comprises three processes. These are: (1) refrigerating process in which the steering wheel 1 having burr 6 is refrigerated to 0° C. to -100° C., more preferably -40° C. to -60° C., (2) blast treatment process in which burr 6 is removed from the cover body 1c by projecting grinding lubricant onto the steering wheel 1 to result in burr-free steering wheel 1B and (3) drying process in which the steering wheel 1B is dried.
In the above mentioned process for refrigerating a steering wheel, refrigeration to 0° C. to -100° C. is effected by introducing liquified inert gas such as liquid nitrogen into a processing chamber.
The above mentioned blast treatment process is effected by projecting a grinding lubricant onto a steering wheel in a refrigerated processing chamber by using a projection machine. Grinding lubricant is non-ferrous and appropriate particle size or the quality of the grinding lubricant is chosen according to the quality of the material which composes the cover body 1c.
In this blast treatment process, the refrigerated steering wheel can be rotated while grinding lubricant is projected onto the steering wheel in order to remove burr effectively.
The above mentioned drying process is carried out to avoid the condensation of water on the steering wheel. If the refrigerated steering wheel, from which burr has been removed during the blast treatment process, is allowed to sit in the air, water condenses on the exposed part of the steering wheel by means of which the steering wheel is to be installed onto a column shaft and causes corrosion in this part.
The above mentioned method of processing a steering wheel is carried out by using steering wheel processing installation 10. This processing installation 10, as shown in FIGS. 4-11 inclusive, comprises a shot blast apparatus 3 which can refrigerate and then blast treat the steering wheel 1 and a drying apparatus 11, such as high frequency induction heating apparatus, which heat dries the steering wheel 1B previously treated with the shot blast apparatus 3 and moving on a belt-conveyor system 11a.
The above mentioned shot blast apparatus 3 comprises the following as indicated in FIGS. 4-11 inclusive:
(1) a frame 12 made of stainless steel which is formed to define the perimeter;
(2) a casing 14, made of stainless steel, which is fixed on the frame 12 and the inside of which includes a cylindrical treatment chamber 13;
(3) a rotary shaft 15, made of stainless steel, which is installed rotatably in the top 14a and bottom 14b walls of the casing 14 through respective bearings 15a so as to be located in the center of the treatment chamber 13;
(4) plural partition walls which are fixed on the rotary shaft 15 by means of welding or the like and divide the treatment chamber into a plurality of compartments. Each compartment can hold one steering wheel 1. In this embodiment, six partition walls 17 divide the treatment chamber into six compartments 16;
(5) a disk-shaped supporting plate 19, made of stainless steel, which has a number of holes 18 and is fixed to the lower part of the partition walls 17 by means of welding or the like so that this plate can cover the lower part of the partition walls 17;
(6) a rotating apparatus 26 for steering wheel supporting stands 20 which comprises six steering wheel supporting stands 20 which rotatably support steering wheels 1 in approximately the center of the respective treatment compartments 16 by means of respective bearings 20a and respective pulleys 21 which are attached to respective shafts 20b attached to respective supporting stands 20, a driving pulley 23 fixed to a shaft 23b which is installed rotatably in the lower wall 14b of the frontal part of the casing 14 through the bearing 23a, a similarly located and installed guide pulley 22, and a motor 24 which drives the shaft 23b, and a belt 25 which transmits rotation of the driving pulley 23 to the pulleys 21, and the guide pulley 22;
(7) a door and door opening 27 which is formed in the side wall 14c at the front part of the casing 14 and opens a single processing compartment 16;
(8) a refrigerant supplying apparatus 28 installed on the upper wall 14a of the casing 14 and which supplies refrigerant inert gas such as liquid nitrogen, liquid carbon dioxide and the like to the second, third and fourth processing compartments 16, if the processing compartment 16 which communicates with the opening 27 is denominated the first processing compartment 16;
(9) a projection machine 30 which is installed on the upper wall 14a of the casing 14 at the position corresponding to the fourth processing compartment 16 and projects grinding lubricant to the inside of the processing compartment 16 from an opening;
(10) a hopper 31, which lets grinding lubricant fall to the inside of the frame 12, formed at the lower wall 14b of the casing 14 and located at the position corresponding to the processing compartment into which grinding lubricant is projected by the projection machine 30;
(11) a separating machine 32 which is installed in the frame 12 and separates from each other grinding lubricant and dust such as burr and the like dropping from the hopper 31;
(12) a grinding lubricant supplying apparatus 33 which supplies grinding lubricant separated by the separation machine 32 to the projection machine 30;
(13) a rotary shaft driving gear 34 which rotates the rotary shaft 15 intermittently or at a fixed low speed.
The above mentioned refrigerant supplying machine 28, as shown in FIG. 10, comprises a refrigerant tank 35, a supplying pipe 36 which supplies refrigerant stocked in the refrigerant tank 35 to the second to fourth processing compartments 16, respective magnetic valves 37 installed in respective supplying conduits 36a, 36b, 36c connecting the supplying pipe 36 to the respective second to fourth processing compartments 16, respective temperature sensors 38, installed in the second to fourth processing compartments 16, a controller 39 which opens and shuts the magnetic valves 37, respectively, according to signals generated by the respective temperature sensors 38, and respective exhaust pipes 40, which exhaust to the outside evaporated refrigerant gas from inside of the respective second to fourth processing compartments 16, the exhaust pipes 4 being located at the upper wall 14a of the casing 14.
The above mentioned separating machine 32, as shown in FIG. 11, comprises a coarse vibrating screen 32a for burr separation which receives grinding lubricant and dust such as burr and the like that drops from the hopper 31 and separates burr larger than grinding lubricant, a vibrating screen 32b for grinding lubricant separation which separates grinding lubricant from the material dropping from the coarse vibrating screen 32a, a container 32c which stocks fine dust such as burr dropping from the screen 32b, a vibrator 32d which vibrates the container 32c as well as the vibrating screens 32b and 32a, a tank 32f which receives through a pipe 32e large burr separated by the coarse vibrating screen 32a, and a dust tank 32h which receives dust such as small burr and the like from the container 32c through a pipe 32g.
The above mentioned grinding lubricant supplying machine 33, as shown in FIG. 11, comprises a tank 33b for the grinding lubricant which is supplied with grinding lubricant 29 separated by the vibrating screen 32b through a pipe 33a, an aspirating pipe 33d of which the conical opening 33c is located inside of the grinding lubricant tank 33b and the extremity connecting part is located outside of the tank 33b, a grinding lubricant transporting pipe 33f of which the one end is connected to the aspirating pipe 33d and the other end to an introducing pipe 33e installed in the aspiratory side of the projection machine 30, a damper 33g which opens and shuts the opening 33c of the aspirating pipe 33d installed within the grinding lubricant tank 33b, and a magnetic solenoid 33h which opens and shuts the damper 33g. Grinding lubricant 29 stocked in the grinding lubricant tank 33b is aspirated, by rotating an impeller 30a driven by the projection machine 30, through the aspirating pipe 33d, grinding lubricant transporting pipe 33d and introducing pipe 33e, and is projected against the steering wheel 1A by the impeller 30a of the projection machine 30.
Projection of grinding lubricant is readily stopped by shutting the opening 33c of the aspirating pipe 33f by operating the damper 33g by means of the magnetic solenoid 33h.
The above mentioned drying apparatus 11, as shown in FIG. 12 and FIG. 13, is equipped with a belt conveyor 11a which carries a steering wheel 1B on to the inside of the tunnel-shaped casing 11b and with a high frequency induction heating apparatus 11c at both sides of the casing 11b.
The drying apparatus 11 heat dries the steering wheels 1B so that the dried steering wheels are at room temperature.
The shot blast apparatus 3 starts the steering wheel supporting stand rotating apparatus 26, the refrigerant supplying apparatus 28, the projection machine and the rotary shaft driving ear 34.
Consequently, the steering wheel supporting stand 20 supports and rotates steering wheels 1 which are placed thereon through the opening 27 of the casing 14.
As each processed steering wheel 1B is carried by the supporting stand 20 to the opening 27, it is removed from the processing compartment 16 and an unprocessed steering wheel 1 is placed through the opening 27 on the area of the supporting stand 20 formerly occupied by the just removed processed steering wheel 1B.
The processing compartment 16, where the steering wheel 1 to be processed is supported, rotates and moves to become the second, third, fourth, fifth and sixth compartments in that order by the drive of the rotary shaft driving gear 34.
The steering wheels 1 are progressively refrigerated to the desired temperature by the refrigerant supplying apparatus 28 which refrigerates the second, third and fourth processing compartments by the rotation of the compartments to the positions corresponding to the second, third and fourth compartments.
At the position corresponding to the fourth compartment, grinding lubricant is projected from the projection machine 30 and burr of the cover body 1c of the refrigerated steering wheel 1A is removed.
After that, these compartments rotate to the positions corresponding to the fifth and sixth compartments and the first compartment having the opening 27.
The steering wheels 1, 1A, 1B, which are supported by each steering wheel supporting stand 20, are rotated by the rotating apparatus 26.
The blast treatment can be done efficiently by refrigeration and the projection machine 30.
As the steering wheel 1B processed by the shot blast apparatus 3, is in the frozen state, it is supplied by hand or by robots to the drying apparatus 11 and dried so that corrosion is not generated by condensation of atmospheric moisture onto exposed metallic parts of the steering wheels 1B even when the steering wheels 1B are left in the air.
Grinding lubricant projected by the projection machine 30 circulates as follows: projection machine 30→processing compartment 16→hopper 31→separating machine 32→grinding lubricant supplying apparatus 33→projection machine 30. This enables more efficient utilization of grinding lubricant and since grinding lubricant is refrigerated when it passes through the processing compartment 16 or the hopper 31 and is projected in the frozen state, the blast effect is increased.
Further, to keep the circulation path of grinding lubricant cool, the peripheries of the casing 30b of the projection machine 30, the hopper 31, separating machine 32 and the grinding lubricant supplying apparatus 33 are covered with insulating material, which enables keeping the grinding lubricant frozen and avoiding the aggregation of grinding lubricant thereby allowing its efficient flow.
Now, other embodiments of this invention, shown in FIGS. 14-17 inclusive, will be discussed. Further, in the description of these embodiments, duplicate description for the components which are identical in the various embodiments of this invention will be omitted by giving identical symbols to identical components.
In the processing installation 10A shown in FIG. 14 and FIG. 15, the significant difference is that a high frequency induction heat drying apparatus 41 which heat dries the blast treated steering wheel 1B is provided so that the inside of the sixth processing compartment located upstream of the opening 27 of the casing 14 can be heated.
It will be appreciated that it is possible to obtain the identical effect with the processing installation 10A as with the processing installation 10.
The processing installation 10A is suitable for the processing of the steering wheel of which the cover body is made of synthetic resin material treatable at relatively higher temperature of refrigeration, for example 0° C. to -10° c.
In the processing installation shown in FIG. 16 and FIG. 17, the significant difference is that a shot blast apparatus 3A, which refrigerates the steering wheel 1 by supplying refrigerant into a processing compartment 16 after the steering wheel 1 is introduced into that processing compartment 16, as provided.
After that, the blast treatment is done by projecting grinding lubricant against the steering wheel 1A by the projection machine 30, and the blast-treated steering wheel 1B is taken out of the processing compartment 16 and is supplied to the drying apparatus by hand or by robots.
It will be appreciated that it is possible to obtain an identical effect with the processing installation 10B as with the processing installation 10. | A soft synthetic resin, such as polyurethane, body is molded onto a metallic steering wheel frame except for a part thereof intended for installation of the steering wheel onto a column shaft and a soft burr formed on the resultant covered steering wheel along the parting line of the mold is removed by refrigerating the steering wheel to make the burr hard and fragile and then removing the burr by shot blast treatment, whereafter the steering wheel is heat dried to eliminate water from the atmosphere condensing on the exposed metallic installation part of the steering wheel and prevent resulting corrosion of that part. | 1 |
BACKGROUND
[0001] FIG. 1 is an illustration of several related art nuclear fuel bundles 10 and core components commonly encountered in existing nuclear power technology. As shown in FIG. 1 , one or more fuel bundles 10 containing several individual fuel rods may be placed within a reactor core in conventional fuel placement strategies. A channel 20 may surround the fuel rods in each bundle 10 , providing directed coolant and/or moderator flow within bundles 10 and/or facilitating manipulation of bundles 10 as a single rigid body. Control rods or cruciform control blades 60 may be extended from set core locations between bundles to absorb neutrons and control reactivity and ultimately control reactivity by a degree of insertion or withdrawal from between the fuel bundles 10 . Fuel support 70 may support and align bundles 10 at constant positions within the core.
[0002] FIG. 2 is a quadrant map of a related art Boiling Water Reactor (BWR) core, illustrating fuel bundle locations within one quarter of the core. Reactor cores typically are conveniently symmetrical about at least two perpendicular axes, such that a quadrant map of FIG. 2 conveys the makeup of the entire core. As shown in FIG. 2 , individual bundle locations are occupied by fresh (shown with diagonal or cross-hatched fill) or burnt (shown with no fill) fuel bundles at the start of a fuel cycle, before commencement of power operations in the core. Fresh bundles are bundles that have not previously been exposed to neutron flux during power operations, i.e., never been burnt, whereas burnt fuel bundles have received such exposure, typically over one or more fuel cycles lasting 1-2 years. As such, burnt fuel bundles typically have exposure, or burnup, of several GWd/ST.
[0003] Fresh fuel bundles may have different starting enrichments of fissile material content. For example, in some BWR designs, outer-enrichment bundles (shown in cross-hatched fill) may include approximately 4.3% Uranium-235 fuel, and inner-enrichment bundles (shown in diagonal fill) may include approximately 4.2% Uranium-235 fuel. Varying enrichments, such as the one shown in FIG. 2 , may permit a flatter radial power profile in the core and/or achieve other operational effects. Further, in some BWR designs, bundles may also possess varying distributions and concentrations of burnable poisons/neutron absorbers to suppress reactivity and optimize operational characteristics. As shown in FIG. 2 , at startup related art nuclear fuel cores include an outer peripheral ring of stale fuel bundles surrounding an inner peripheral ring of fresh, high-enrichment fuel bundles. A central region may include 50% or more fresh bundles in order to maximize fresh fuel content over an even distribution, permitting longer operating cycles with lower downtime.
[0004] In related art BWRs, cruciform control blades 60 extend centrally between groupings of four fuel bundles in order to absorb neutrons and control the nuclear chain reaction in the core. As shown in FIG. 2 , the groupings of four fuel bundles, between which control blades extend, are identified in bolded outline as controlled bundles, or control cells. Bundles within the controlled bundle groups conventionally have one face closest to a control blade used during the fuel cycle; such bundles are referred to as controlled bundles and their positions as controlled positions in control cells of four bundles. Different control blades in different control cells, usually four or five per quadrant, are conventionally alternately inserted and withdrawn in different and complex control blade sequences in order to manage reactivity and power distribution and spread control blade usage across several different blades and fresh fuel bundles within the core.
[0005] As shown in FIG. 2 , in order to maximize the number of fresh fuel bundles used in a longer cycle over an even core distribution, several fresh fuel bundles may be placed in controlled positions adjacent to operated control blades within the inner portion of the core. Due to conventional operation of control blades, all fresh fuel bundles in the central core portion may be controlled—having direct exposure to control blades actively moved to finely control reactivity—throughout an entire fuel cycle. Use of fresh fuel bundles in controlled locations causes several problems, including corrosion and channel bowing that worsens in later cycles, and a need to perform complex and/or lower-power control blade sequence exchanges due to this positioning that worsen plant economics. Some related art fuel cores have avoided this problem by using a Control Cell Core loading strategy, where only burnt fuel bundles are placed closest to operated control blades, resulting in fewer fresh bundles used in the central portion of the core and shorter operating cycles.
SUMMARY
[0006] Example embodiments include nuclear cores with at least two control cell types that differ in total reactivity. The different control cell types may be placed in numbers and/or positions the enhance fuel and core performance. Example cores may include an outermost region with lower reactivity fuel bundles, an inner peripheral region lining the outer peripheral region and having higher reactivity fuel bundles and at least portions of the outermost control cells, and an inner core lining the inner peripheral region and having inner control cells with only fuel bundles of lower reactivity. The lower reactivity bundles may be burnt, and the higher reactivity bundles may be fresh, for example, the outer control cells can include two fresh fuel bundles and the inner control cells can include only burnt fuel bundles. However, reactivity differences may also be achieved through fuel enrichment variation, burnable poison presence, etc. In an example with a conventional BWR, the inner peripheral region may be three bundles thick, most of which can be higher reactivity fuel bundles, and the outer peripheral region may be three bundles thick. In this instance, there may be thirteen inner control cells. Example embodiments are not limited to BWRs or specific placements, but are compatible with any type of core control cell setup, including control cells formed with control rods or cruciform control blades having four fuel bundles positioned in each corner the blades. Different core geometries are easily outfitted with example embodiments; for example, in an ESBWR, the inner core region may have twenty-five inner control cells.
[0007] Example methods include creating and/or operating nuclear cores with multiple types of control cells. For example, a core may be loaded to form an example embodiment core. In example methods, control elements in only the inner control cells may be moved to control core reactivity, except at sequence exchanges after several weeks or months of operation, such as after 3 GWd/ST. At such a sequence exchange, a single coarse movement of control elements in the outer control cells may be made in order to resume controlling day-to-day reactivity with the inner control cells. Near the end of a cycle, when reactivity is lowest, reactivity in the core may be controlled only with inner control cells, and control elements in the outer control cells can be fully withdrawn.
[0008] Example embodiments and methods can provide high (approximately 50%) fresh fuel volumes for each cycle, enabling longer cycles and better plant economics. Example methods and embodiments further provide high power density and low leakage through segregating fuel types by reactivity in the periphery and inner portions of the core. Example methods and embodiments further may enable simplified and non-interrupting movement of control elements in the inner core to fully control reactivity without causing negative control element and fuel interactions.
BRIEF DESCRIPTIONS OF THE DRAWINGS
[0009] Example embodiments will become more apparent by describing, in detail, the attached drawings, wherein like elements are represented by like reference numerals, which are given by way of illustration only and thus do not limit the terms which they depict.
[0010] FIG. 1 is an illustration of related art fuel bundles loaded into a core having cruciform blades for control elements.
[0011] FIG. 2 is a quadrant map of a related art commercial nuclear reactor core.
[0012] FIG. 3 is a quadrant map of an example embodiment nuclear core.
[0013] FIG. 4 is a quadrant map of another example embodiment nuclear core.
DETAILED DESCRIPTION
[0014] This is a patent document, and general broad rules of construction should be applied when reading and understanding it. Everything described and shown in this document is an example of subject matter falling within the scope of the appended claims. Any specific structural and functional details disclosed herein are merely for purposes of describing how to make and use example embodiments or methods. Several different embodiments not specifically disclosed herein fall within the claim scope; as such, the claims may be embodied in many alternate forms and should not be construed as limited to only example embodiments set forth herein.
[0015] 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 element could be termed a second element, and, similarly, a second element could be termed a first element, without departing from the scope of example embodiments. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.
[0016] It will be understood that when an element is referred to as being “connected,” “coupled,” “mated,” “attached,” or “fixed” 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. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between”, “adjacent” versus “directly adjacent”, etc.). Similarly, a term such as “communicatively connected” includes all variations of information exchange routes between two devices, including intermediary devices, networks, etc., connected wirelessly or not.
[0017] As used herein, the singular forms “a”, “an” and “the” are intended to include both the singular and plural forms, unless the language explicitly indicates otherwise with words like “only,” “single,” and/or “one.” It will be further understood that the terms “comprises”, “comprising,”, “includes” and/or “including”, when used herein, specify the presence of stated features, steps, operations, elements, ideas, and/or components, but do not themselves preclude the presence or addition of one or more other features, steps, operations, elements, components, ideas, and/or groups thereof.
[0018] It should also be noted that the structures and operations discussed below may occur out of the order described and/or noted in the figures. For example, two operations and/or figures shown in succession may in fact be executed concurrently or may sometimes be executed in the reverse order, depending upon the functionality/acts involved. Similarly, individual operations within example methods described below may be executed repetitively, individually or sequentially, so as to provide looping or other series of operations aside from the single operations described below. It should be presumed that any embodiment having features and functionality described below, in any workable combination, falls within the scope of example embodiments.
[0019] Applicants have recognized problems existing in several diverse types of nuclear fuel cores with control element placement near certain fuel bundles. Particularly, Applicants have identified that while a maximization of fresh fuel within a nuclear fuel core at any beginning of cycle will permit longer cycle operating times and reduce outage intervals, such maximization can also force fresh fuel bundles to be placed directly next to control elements, which may cause several problems over the life of the fuel, including corrosion, channel-blade interference, and pellet-cladding interactions. Applicants have further recognized that Control Cell Core management techniques, where fresh fuel bundles are not placed directly adjacent to control elements, restricts the amount of fresh fuel that can be placed within a core, as well as limiting placement of fresh fuel in optimal positions for power management, resulting in worsened burnup/efficiency and shorter operating cycles. Example embodiments and methods below uniquely address these and other problems identified by Applicants in related nuclear fuel management technologies for a diverse array of nuclear plants.
Example Embodiments
[0020] Example embodiments of the invention include nuclear fuel cores having higher reactivity fuel in lower proportions adjacent to control elements. Lower reactivity fuel is placed in greater proportions adjacent to control elements, while permitting overall fuel content and operating lifespan of the core to be substantially maintained. Example embodiments form two or more different types of positions subject to direct control element exposure—a larger number of controlled positions of a first type having a higher population of burnt and/or lower-enrichment fuel; and a smaller number of controlled positions of a second type having a higher population of fresh and/or higher-enrichment fuel. Specific example embodiments describing how this configuration may be achieved across several different core designs are discussed below, with the understanding that specific placements of the differing types of controlled positions within various regions in example embodiments can be varied based on core design and reactivity needs. It is further understood that any specific plant type, fuel type, enrichment level, exposure level, and/or control element configuration discussed in these example embodiments are not limiting but merely examples of the breadth of nuclear reactor technologies across which example embodiments may be implemented. Example methods of forming and using example embodiments are described thereafter.
[0021] FIG. 3 is a quadrant map of an example embodiment fuel core 100 ; for example, FIG. 3 may be an initial loading map for a particular cycle. Core 100 may be useable in existing boiling water reactors; for example, core 100 may be useable in similar plants as the related fuel core loading strategy of FIG. 2 . As shown in FIG. 3 , core 100 may include a typical BWR fuel core geometry, such as a 17-bundle radius quadrant.
[0022] Example embodiment core 100 can be visualized in three regions: an outer periphery 120 ; an inner periphery 130 ; and an inner core 140 . Outer periphery 120 may be up to three fuel bundles thick from an edge of the core in a reactor and include mostly burnt fuel bundles 111 (no fill). Burnt fuel bundles 111 are bundles that have experienced burnup in previous operating cycles or otherwise have been exposed to neutron flux or have significantly lower reactivity than fresh fuel bundles.
[0023] Inner periphery 130 may be up to three fuel bundles thick and include a larger proportion of higher enrichment fresh fuel bundles 110 (cross-hatched fill). Inner core 140 includes the remainder of the core within inner periphery 130 and includes a mix of lower enrichment fresh fuel bundles 112 (diagonal fill) and burnt fuel bundles 111 . Fresh fuel bundles 110 and 112 may have little or no previous neutron flux exposure compared to burnt fuel bundles 111 . For example, fresh fuel bundles 110 and 112 may be newly-manufactured bundles previously unused in core operations. Higher enrichment fresh fuel bundles 110 and lower enrichment fresh fuel bundles 112 may differ in fissile material enrichment by any degree required for core 100 operations and optimization. For example, higher enrichment fresh fuel bundles 110 may contain 4.3% Uranium-235 fuel, and lower enrichment fresh fuel bundles 112 may include approximately 4.2% Uranium-235 fuel. Fuel bundles 110 and 112 may each have distinct distributions and concentrations of burnable absorber as well.
[0024] In other example embodiments, burnt fuel bundles 111 , higher enrichment fresh fuel bundles 110 , and lower enrichment fresh fuel bundles 112 may be replaced with fuel bundles having a same age but varying initial enrichment and burnable absorber concentration in order to achieve the same reactivity differences as between bundles 110 , 111 , and 112 in example embodiment core 100 . Similarly, reactivity differences may be achieved by using bundles of a same initial enrichment but having three different operating exposure levels, such as fresh, burnt 1-cycle, or burnt 2-cycles in place of higher enrichment fresh fuel bundles 110 , lower enrichment fresh fuel bundles 112 , and burnt fuel bundles 111 . Yet further, reactivity and enrichment differences between all fresh fuel bundles 110 and 112 may be non-existent or minimal, such as where a single fuel type and enrichment is used throughout an entire example core having only differently-aged fuel bundles.
[0025] Comparing FIGS. 2 and 3 , it can be seen that example embodiment core 100 includes more fresh fuel bundles in inner periphery region 130 and does not adhere to a strict checkerboard pattern for fresh and stale fuel bundles in inner core 140 . In this way, example embodiment core 100 may include substantially the same amount of fresh fuel bundles 110 and 112 and/or fissile mass and reactivity as related art cores loaded for maximum operation cycle length. Instead of a strict checkerboard alteration between burnt fuel bundles 111 and lower enrichment fresh bundles 112 in inner core 140 , example embodiment core 100 includes some groupings of fuel bundles that include more burnt bundles 111 . As seen in FIG. 3 , four burnt fuel bundles 111 may be grouped about a control blade so as to form a priority control cell 142 that includes less fresh fuel bundles than non-priority control cells 141 . For example, as shown in FIG. 3 , priority control cells 142 , shown by a solid black line surrounding bundle locations so controlled, may include only burnt fuel bundles 111 . Priority control cells 142 may be inner-most control cells within inner region 140 . Non-priority control cells 141 , shown by a broken black line surrounding bundle locations so controlled, may include a mix of burnt fuel bundles 111 and fresh bundles 112 similar to related art core of FIG. 1 and may be positioned closer to or in inner periphery 130 , outside of priority control cells 142 .
[0026] FIG. 4 is a quadrant map of an example embodiment fuel core 200 ; for example, FIG. 4 may be an initial loading map for a particular cycle. Core 200 in the example of FIG. 4 may be useable in an Economic Simplified Boiling Water Reactor (ESBWR). As shown in FIG. 4 , core 200 may include a typical ESBWR fuel core geometry, such as a 19-bundle radius quadrant.
[0027] Example embodiment core 200 can be visualized in three regions: an outer periphery 220 ; an inner periphery 230 ; and an inner core 240 . Outer periphery 220 may be up to three fuel bundles thick from an edge of the core in a reactor and include mostly once-burnt fuel bundles 213 (dashed fill) and twice-burnt fuel bundles 211 (no fill). Burnt fuel bundles 211 and 213 are bundles that have experienced burnup in previous operating cycles or otherwise have been exposed to neutron flux or have significantly lower reactivity than fresh fuel bundles. For example, once-burnt fuel bundles 213 have approximately 15-23 GWd/ST exposure from a single two-year operating cycle in known ESBWR cores, and twice-burnt fuel bundles 211 may have more burnup, such as 35-40 GWd/ST exposure.
[0028] Inner periphery 230 may be one to three fuel bundles thick and include a larger proportion of higher enrichment fresh fuel bundles 210 (cross-hatched fill). Inner core 240 includes the remainder of the core within inner periphery 230 and includes a mix of mostly lower enrichment fresh fuel bundles 212 (diagonal fill) and once-burnt fuel bundles 213 . Fresh fuel bundles 210 and 212 may have little or no previous neutron flux exposure compared to burnt fuel bundles 211 and 213 . For example, fresh fuel bundles 210 and 212 may be newly-manufactured bundles previously unused in core operations. Higher enrichment fresh fuel bundles 210 and lower enrichment fresh fuel bundles 212 may differ in fissile material enrichment by any degree required for core 200 operations and optimization. For example, higher enrichment fresh fuel bundles 210 may contain 4.3% Uranium-235 fuel, and lower enrichment fresh fuel bundles 212 may include approximately 4.2% Uranium-235 fuel. Fuel bundles 210 and 212 may each have distinct distributions and concentrations of burnable absorber as well.
[0029] In other example embodiments, twice-burnt fuel bundles 211 , once-burnt fuel bundles 213 , higher enrichment fresh fuel bundles 210 , and lower enrichment fresh fuel bundles 212 may be replaced with fuel bundles having a same age but varying initial enrichment and burnable absorber concentration in order to achieve the same reactivity differences as between bundles 210 , 211 , 212 , and 213 in example embodiment core 200 . Similarly, reactivity differences may be achieved by using bundles of a same initial enrichment but having three different operating exposure levels, such as fresh, burnt 1-cycle, or burnt 2-cycles in place of higher enrichment fresh fuel bundles 210 , lower enrichment fresh fuel bundles 212 , and burnt fuel bundles 211 and 213 . Yet further, reactivity and enrichment differences between fresh fuel bundles 210 and 212 may be non-existent or minimal, such as where a single fuel type and enrichment is used throughout an entire example core having only differently-aged fuel bundles.
[0030] Example embodiment core 200 may include substantially the same amount of fresh fuel bundles 210 and 212 and/or fissile mass as related art ESBWR cores loaded for maximum operation cycle length. Example embodiment core 200 includes some groupings of fuel bundles that include more burnt bundles 211 and/or 213 . As seen in FIG. 4 , four once-burnt fuel bundles 213 may be grouped about a control blade so as to form a priority control cell 242 that includes less fresh fuel bundles and less reactivity than non-priority control cells 241 . For example, as shown in FIG. 4 , priority control cells 242 , shown by a solid black line surrounding bundle locations so controlled, may include only once-burnt fuel bundles 213 . Priority control cells 242 may be inner-most control cells within inner region 240 . Non-priority control cells 241 , shown by a broken black line surrounding bundle locations so controlled, may include a mix of burnt fuel bundles 211 and 213 and fresh bundles 112 and may be positioned closer to or in inner periphery 230 .
[0031] Example embodiment cores are useable with fuel assemblies described in co-owned application Ser. No. 12/843,037 filed Jul. 25, 2010 titled “OPTIMIZED FUEL ASSEMBLY CHANNELS AND METHODS OF CREATING THE SAME,” which is incorporated herein by reference in its entirety. For example, fuel bundles that are to be placed in controlled positions in example embodiment cores may use channels with Zircaloy-4 to additionally guard against shadow corrosion.
[0032] Other example embodiment cores may be useable in Advanced Boiling Water Reactors, other Light and Heavy Water Reactors, or any nuclear reactor having nuclear chain reaction control structures extending into the core that are useable to control reactivity, with modifications of size and initial enrichments made for the appropriate type of core and control element placement.
Example Methods
[0033] Example methods include loading and/or operating nuclear cores. Example methods may take particular advantage of nuclear cores loaded as described above in example embodiments, but it is understood that example methods and embodiments may be used separately.
[0034] During an operating outage or other time when a core is available for loading, an operator or other party may load a core so as to achieve loading patterns consistent with those described in the above example embodiments. For example, existing fuel bundles may be shuffled into stale fuel positions based on their age, enrichment, and/or reactivity. Such shuffling may open a number of positions about an inner periphery and non-primary controlled locations within the inner core. A desired number of oldest or least functional fuel bundles may be removed from the core. Fresh fuel bundles may be procured and installed in locations vacated by the fuel shuffle, based on enrichment or other parameters. Such shuffling may create a fuel core resembling example embodiments described above or related embodiments.
[0035] During operation of a core, control elements may be used to control the nuclear chain reaction. For example, in related art BWRs, a cruciform control blade may be extended between four adjacent bundles in a control cell to control reactivity. Example methods include using only control elements directly adjacent to fuel bundles having relatively lower reactivity and/or being previously burnt and not fresh for fine, day-to-day reactivity control within a core. In example methods, control elements directly adjacent to fresh or higher reactivity fuel bundles are relatively stationary and used for only coarse reactivity adjustments at a few set points during the fuel cycle; these control elements may be entirely removed from the core—i.e., not used at all for reactivity control—during the later portions of the cycle.
[0036] As a specific example method in connection with the example embodiment of FIG. 4 , an operator or other party may load an ESBWR core 200 so as to create priority control cells 242 including only burnt fuel associated with control blades in a central area of inner core 240 of core 200 . Non-priority control cells 241 including some fresh and/or high-reactivity fuel bundles are created at control blade positions nearer or in the inner periphery region 230 , outside of the priority control cells 242 . During sequence exchange intervals occurring at approximately every 3 GWd/ST of operation, for example, control blades in non-priority cells 241 may be moved to a desired coarse reactivity control position. Otherwise, control blades in non-priority cells 241 are not required to be moved for reactivity control, and control blades only in priority control cells 242 may be moved for fine reactivity control throughout the sequence. During the final quarter of operation, at approximately 15 GWd/ST cycle average exposure, for example, control blades in non-priority cells 241 may be fully withdrawn and not necessary to control reactivity. At all points during the cycle, control blades associated with priority cells 242 may be freely moved to make fine adjustments to core reactivity. During the final quarter of the cycle, control blades in priority cells 242 alone may be used to control core reactivity; that is, control blades in priority cells 242 may be the only blades within core 200 after approximately 15 GWd/ST.
[0037] Example embodiments and/or methods may provide fuel cores in existing and future-designed reactors with large enough fresh fuel reload batch sizes to accommodate longer operating cycles with higher power densities, while reducing or eliminating concerns associated with placing fresh or higher reactivity fuel directly adjacent to control elements. Placement of fresh fuel in greater numbers about an inner periphery of the core and in limited number of controlled positions may provide a low-leakage core having several inner controlled positions not including fresh or high reactivity fuel. In this way, shadow corrosion, pellet-cladding interaction, and resulting channel distortions and negative control element-channel interaction may be reduced by avoiding placement of the newest and/or highest reactivity fuel bundles closest to active control elements. In addition to longer operating cycle compatibility, high power density, lower leakage, and reduced channel distortion, example embodiments and/or methods may permit nuclear fuel cores to be operated with simplified control element maneuvers; particularly, example embodiments and methods may permit only a subset of control elements to be used for immediate, fine reactivity control and reduce a number of total control element sequences and exchanges throughout an entire operating cycle and/or reduce any need to lower power during such complicated exchanges. These and other advantages and solutions to newly-identified core operating problems are addressed by the various example embodiments and methods described above.
[0038] Example embodiments and methods thus being described, it will be appreciated by one skilled in the art that example embodiments may be varied and substituted through routine experimentation while still falling within the scope of the following claims. For example, a variety of different nuclear fuel types and core designs are compatible with example embodiments and methods simply through loading and operational strategy—and without any core geometry or structural changes—and fall within the scope of the claims. Such variations are not to be regarded as departure from the scope of these claims. | Cores include different types of control cells in different numbers and positions. A periphery of the core just inside the perimeter may have higher reactivity fuel in outer control cells, and lower reactivity cells may be placed in an inner core inside the inner ring. Cores can include about half fresh fuel positioned in higher proportions in the inner ring and away from inner control cells. Cores are compatible with multiple core control cell setups, including BWRs, ESBWRs, ABWRs, etc. Cores can be loaded during conventional outages. Cores can be operated with control elements in only the inner ring control cells for reactivity adjustment. Control elements in outer control cells need be moved only at sequence exchanges. Near end of cycle, reactivity in the core may be controlled with inner control cells alone, and control elements in outer control cells can be fully withdrawn. | 6 |
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