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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a new and improved system for use in clearing clogged drains and, more particularly, pertains to a clog dislodging device employing a number of different sized drain closure members.
2. Description of the Prior Art
The use of devices for cleaning clogged drain lines is known in the prior art. More specifically, devices for cleaning clogged drain lines heretofore devised and utilized for the purpose of cleaning clogged drain lines with devices employing high pressure air are known to consist basically of familiar, expected, and obvious structural configurations, notwithstanding the myriad of designs encompassed by the crowded prior art which has been developed for the fulfillment of countless objectives and requirements.
The prior art discloses a large number of devices for clearing clogged drain lines. By way of example, U.S. Pat. No. 5,193,245 to Brzoska; U.S. Pat. No. 4,674,137 to Girse; U.S. Pat. No. 4,629,128 to Lawrence; and U.S. Pat. No. 4,736,473 to Gellatly all disclose devices for removing clogs from drain lines.
In this respect, the system for use in clearing clogged drains according to the present invention substantially departs from the conventional concepts and designs of the prior art, and in doing so provides an apparatus primarily developed for the purpose of providing a clog dislodging device employing a number of different sized drain closure members.
Therefore, it can be appreciated that there exists a continuing need for a new and improved system for use in clearing clogged drains which can be used for a clog dislodging device employing a number of different sized drain closure members. In this regard, the present invention substantially fulfills this need.
SUMMARY OF THE INVENTION
In view of the foregoing disadvantages inherent in the known types of devices for cleaning clogged drain lines now present in the prior art, the present invention provides an improved system for use in clearing clogged drains. As such, the general purpose of the present invention, which will be described subsequently in greater detail, is to provide a new and improved system for use in clearing clogged drains and methods which have all the advantages of the prior art and none of the disadvantages.
To attain this, the present invention essentially comprises a new and improved hand-held drain cleaning system employing pressurized air, the system comprising, in combination, a handle component having a first end, a second end, an exterior surface, an interior surface, an interior area, an aperture formed within the second end, a one-way valve positioned over the aperture for allowing air to flow from the interior area of the handle component, a piston positioned within the interior area of the handle, a rod coupled to the piston and extending through the first end of the handle component; a housing component having a first end, a second end, an interior area, and an exterior surface, the first end of the housing component being integral with the second end of the handle component, a cylindrical passage having a first end and a second end, the first end of the cylindrical passage in communication with the interior area of the housing, the second end of the housing being internally threaded, a stopper adapted to be positioned over the first end of the cylindrical passage, the stopper being pivotally secured to the interior area of the housing component; a trigger pivotally secured to the exterior surface of the housing, the trigger having a first orientation and a second orientation, the second orientation of the trigger effecting the pivotal movement of the stopper away from the first end of the cylindrical passage, a spring secured to the exterior surface of the handle component, the spring urging the trigger from its second to its first orientation; an extension member having a first end, a second end and an interior passage, the first end being externally threaded and adapted to engage the internal threads of the second end of the housing component such that the cylindrical passage comes into fluid communication with the interior passage of the extension member; and a plurality of drain closures, each of the drain closures having a first end of a uniform cross-section and a second end, the second end of each of the closures adapted to be positioned within the drain opening, each of the second ends having a different diameter.
There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto.
In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of descriptions and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
It is therefore an object of the present invention to provide a new and improved system for use in clearing clogged drains which has all the advantages of the prior art devices for cleaning clogged drain lines and none of the disadvantages.
It is another object of the present invention to provide a new and improved system for use in clearing clogged drains which may be easily and efficiently manufactured and marketed.
It is a further object of the present invention to provide a new and improved system for use in clearing clogged drains which is of a durable and reliable construction.
An even further object of the present invention is to provide a new and improved system for use in clearing clogged drains which is susceptible of a low cost of manufacture with regard to both materials and labor, and which accordingly is then susceptible of low prices of sale to the consuming public, thereby making such devices for cleaning clogged drain lines economically available to the buying public.
Still yet another object of the present invention is to provide a new and improved system for use in clearing clogged drains which provides in the apparatuses and methods of the prior art some of the advantages thereof, while simultaneously overcoming some of the disadvantages normally associated therewith.
Even still another object of the present invention is to provide a clog dislodging device employing a number of different sized drain closure members.
Lastly, it is an object of the present invention to provide a system for using compressed air to dislodge a clog from a drain. The system includes a main housing defined by a handle component and a minor housing component. The handle component includes a rod and piston for use in delivering compressed air to the minor housing. The device further includes a spring-biased trigger for use in selectively delivering compressed air from the device into a clogged drain. Furthermore, the system of the present invention includes a plurality of drain closure members of various sizes adapted to fit into various sized drains. Thus, the user may select the appropriate sized drain closure depending on the specific application of the device.
These together with other objects of the invention, along with the various features of novelty which characterize the invention, are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and the specific objects attained by its uses, reference should be had to the accompanying drawings and descriptive matter in which there is illustrated preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood and objects other than those set forth above will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings wherein:
FIG. 1 is a side view of the device in accordance with the principles of the present invention.
FIG. 2 is a view taken along line 2--2 of FIG. 1.
FIG. 3 is a sectional view of the device in accordance with the present invention.
FIG. 4 is a view of the extension member in accordance with the present invention.
FIG. 5 is a view of one of the drain closure members in accordance with the present invention.
FIG. 6 is a view of another drain closure member in accordance with the present invention.
The same reference numerals refer to the same parts throughout the various Figures.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference now to the drawings, and in particular to FIG. 1 thereof, the preferred embodiment of the new and improved system for use in clearing clogged drains embodying the principles and concepts of the present invention and generally designated by the reference numeral 10 will be described.
The present invention relates to a hand-held drain cleaning system employing pressurized air. In its broadest context, the system includes a major housing with a handle component and a housing component. The handle component includes a rod and piston disposed within its interior for the purposes of injecting air into the housing component. The housing component is adapted to be placed over a drain and have compressed air delivered therethrough to force out any clogs within the corresponding drain. The various components of the present invention, and the manner in which they interrelate, will be described in greater detail hereinafter.
The handle component 20 of the present invention is defined by a first end 22 and a second end 24. Furthermore, the handle component 20 is defined by an exterior surface, an interior surface and an interior area. The handle component 20 in general constitutes a means for delivering pressurized air into the forward portion of the device. To accomplish this, the handle component 20 includes an aperture formed within its second end 24. Over this aperture a one-way valve 26 is positioned. This one-way valve 26 allows air to flow from the interior area of the handle component 20 and does not allow air to flow into interior area of the handle component. Furthermore, a piston 28 is positioned within the interior area of the handle 20. A cylindrical rod 32 is coupled to one of the ends of this piston 28 for the purposes of driving the piston along the internal area of the handle component. The rod 32 extends through the first end 22 of the handle component 20. At the opposite end of the rod 32 is a user-engageable knob. Thus, the user may manipulate the piston 28 through the length of the internal area of the handle component 20 by way of the rod. Thus, upon a rearward stroke, air is drawn into the handle component 20 by way of an aperture provided within the handle component 20. Then, in the forward motion of the rod 32, air is forced through the one-way valve 26 and into the forward portion of the device. The function of this air and the route it travels to the drain will be described in greater detail hereinafter.
The device further includes a housing component 34 which is defined by a first end 36, a second end 38, an interior area and an exterior surface. The first end 36 of the housing component 34 is integral with the second end 24 of the handle component 20. A cylindrical passage 42 which is defined by a first end and a second end is in communication with the interior area of the housing component 34. The second end of the housing component 34 is internally threaded. The function of these internal threads will be described in greater detail hereinafter. A stopper 44 is adapted to be positioned over the first end of the cylindrical passage. This stopper is pivotally secured to the internal area of the housing component 34.
A trigger 46 which is pivotally secured to the exterior surface of the housing 34 functions to manipulate the stopper 44. More specifically, the trigger 46 has a first orientation and a second orientation with the second orientation of the trigger effecting the pivotal movement of the stopper 44 away from the first end of the cylindrical passage 42. A resilient spring 48 which is secured to the exterior surface of the handle component 20 functions to urge the trigger 46 from its second to its first orientation. In the preferred embodiment, the spring 48 takes the form of a resilient metallic band which is bowed outwardly from the surface of the handle component. This spring can most clearly be seen in FIGS. 1 and 3. The trigger 46 is operatively connected to the stopper 44 by way of a cable which passes through the side of the housing component 34. Thus, pivotal movement of the trigger 46 effects tensioning of the cable and the pivotal movement of the stopper 44.
In order to employ the device of the present invention with hard to reach drain areas, an extension member 52 is provided. This extension member is defined by a first end 54, a second end 56 and an interior passage 58 which extends between the first and second ends. The first end 54 is externally threaded and is specifically adapted to engage the internal threads of the second end 38 of the housing component 34. This threaded engagement insures that the cylindrical passage 42 comes into fluid communication with the internal passage 58 of the extension member 52. Thus, when it is needed, the extension member 52 can be screwed into the housing component 34 to extend the reach of the device.
Furthermore, in an effort to make the present system more compatible with a wide variety of drains, a number of drain closures are included. Each specific drain closures 62 includes a first end 64 and a second end 66. Each of the first ends 64 are of a uniform diameter while the second ends are of an enlarged diameter. Furthermore, in the system, a plurality of such drain closures are provided with each of the second ends being of a different diameter. The second end of each of the closures is specifically adapted to be positioned within the drain opening while the first end is adapted to be secured to the second end 56 of the extension member 52. Alternatively, the first ends of the drain closures can be secured to the second end of the cylindrical passage 42. Two such drain closures are illustrated in FIGS. 5 and 6. As is evident from these illustrations, FIG. 5 is for use with a smaller drain opening while FIG. 6 is for use with a larger drain opening.
Thus in operation the user of the present invention while using the device in its first mode would fill the housing component with compressed air by way of the piston and rod assembly of the handle component. Namely, the operator would move the rod in a linear fashion back and forth to pressurize the interior area of the housing component. The one-way valve would prohibit any compressed air within the housing component from returning into the interior of the handle component. Furthermore, the stopper would prevent any air from escaping from the internal area of the housing component. When enough air was compressed within the internal area of the housing component, the second end of the cylindrical passage associated with the housing component would then be inserted over a drain opening to be unclogged. Next, the operator would maneuver the trigger to its second orientation thus pivoting the stopper away from the first end of the cylindrical passage and thus allowing the compressed air within the housing component to be delivered into the clogged drain. This compressed air would function in blowing any debris within the drain downstream and unclogging the drain.
In alternative uses, the device would be employed in the same manner however the extension member would be threaded into the second end of the housing component. Furthermore, depending on the drain size, an appropriate drain closure would be selected. Namely, a drain closure with the appropriately sized second end would be selected and inserted within the second end of the extension member or the second end of the housing component. In the preferred embodiment, the drain closures are made from an elastomeric material and would be press fit into the second end of the extension member or within the second end of the housing component, more specifically, the second end of the cylindrical passage. The materials for the construction of the handle component and the housing component can be an impact-resistant plastic or a lightweight metal.
As to the manner of usage and operation of the present invention, the same should be apparent from the above description. Accordingly, no further discussion relating to the manner of usage and operation will be provided.
With respect to the above description then, it is to be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention.
Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. | The present invention relates to a system for using compressed air to dislodge a clog from a drain. The system includes a main housing defined by a handle component and a minor housing component. The handle component includes a rod and piston for use in delivering compressed air to the minor housing. The device further includes a spring-biased trigger for use in selectively delivering compressed air from the device into a clogged drain. Furthermore, the system of the present invention includes a plurality of drain closure members of various sizes adapted to fit into various sized drains. Thus, the user may select the appropriate sized drain closure depending on the specific application of the device. | 4 |
BACKGROUND OF THE INVENTION
Retailing businesses and banking institutions are currently suffering substantial financial losses due to unauthorized use of credit cards in the conduct of business at the consumer level. The problem of detecting counterfeit credit cards and unauthorized users of valid cards prior to completion of credit-card transactions has not been effectively solved to date. Banking institutions which are equipped with card-operated banking equipment are generally able to detect an attempted unauthorized use of a credit card because such banking equipment is conveniently connected to the institution's central processor and computer files for "on-line" operation of the equipment at each step in a credit-card transaction. However, the great majority of credit-card transactions by retailers around the world is usually completed in amounts under set credit limits without the convenience of "on-line" computer checking of each step in the transaction. Instead, simple "off-line" credit-card checking techniques are used which are based upon a comparison of the card number against a compiled listing of numbers of unauthorized cards and a visual check of a user's signature against a sample signature. Such lists of numbers of unauthorized cards are largely ineffective in reducing credit losses because of the delay in compiling and distributing the lists, and because such lists do not identify valid cards that have been reproduced or counterfeit cards that bear fictitious numbers.
Even inherently more secure transactions which are controlled by "on-line" interactive computer processing are subject to security violations resulting from insufficiently secured procedures used in issuing cards initially. Unscrupulous personnel within a card-issuing institution may compromise the security of an "on-line" card-operated, computer-controlled system, for example, by causing issuance of a card with an account or identification number that was previously assigned.
SUMMARY OF THE INVENTION
In accordance with the present invention, method and means are provided for securing card-oriented transactions at several levels of interaction between a card-issuing institution, its personnel, its customers and even its suppliers of blank cards. The present invention provides enhanced security against the duplication and proliferation of one valid card and against counterfeit cards with fictitious numbers by securing the interactive transaction between an individual and the institution upon establishment of the individual's new account, as well as securing the transaction involved at the institutional level in issuing the card to the individual. In addition, the present invention operates to secure the card against duplication in instances where each issued card has a unique identification. In this way, the individual may be assured that his interaction with the card-issuing institution is secured and that the institution's interactions with its personnel and its suppliers of cards are secured.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is an illustration of the system involved in issuing a card and in using an issued card in an "off-line" card-checking transaction; and
FIG. 2 is a flow chart illustrating the information supplied to and produced by the apparatus of the present invention; and
FIG. 3 is a block diagram of the apparatus of the present invention for issuing cards to specific individuals in a manner that preserves a high degree of security at all levels of interaction.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1, there is shown a pictorial and schematic diagram of the system of the present invention which operates on the personal identification number (PIN) of an individual (selected and known only by the individual), and on identification information furnished by an operator of the system to generate a credit card 9 which is unique to the individual and which is secured against unauthorized preparation or counterfeiting through multilevels of secured interactions.
In the initial sign-on transaction, an individual may select any code word or set of numbers, or combination thereof, which he may preserve in total secrecy and which he enters 11 initially into the system via any conventional means such as a keyboard, telephone dial apparatus, or the like. In addition, an operator of the system enters an assigned account number 13 (and also identifies himself using his own identification word or number). Optionally, the identification number of the institution (e.g., route and transit number of a bank, etc.) may also be furnished 15. Thus, the individual's secret identifying code (PIN) 11 plus all or an initial part of the new account number 13, plus any desired identification information pertaining to the institution, is supplied to an encoding device 17 for irreversible encryption of the data to generate a first compiled code word, or OFFSET I at the output 19 of the encoding device 17. The encoding device 17 may include a conventional National Bureau of Standards (NBS) data-encryption integrated circuit (commercially available from Motorola, Inc.) having multiple inputs for encoding the signals applied thereto, and may be operated according to a known irreversible algorithm (for example, as disclosed in U.S. Pat. No. 3,938,091 and in U.S. Patent Application Ser. No. 879,784, now issued as U.S. Pat. No. 4,198,619) to yield an OFFSET I of fixed length for any length of applied code words. This initial encryption may be performed on an isolated encrypting device to produce OFFSET I for transmission by conventional means to the next encoding means 23. Thus, the first level of interaction between the institution and the individual which produces the OFFSET I is secured by the individual who retains the secrecy of his own PIN.
At the next level of interaction, the institution is able to secure the transaction against unauthorized operation of the system by unscrupulous personnel. The institution may perform a number of checks and inquiries, as later described, relative to the authority of the system operator, the status of the assigned account number, etc., prior to encoding in the encoding means 23 the new account number, the OFFSET I and a secret identification key 21 that is unique to the institution. Upon successful completion of checks and inquiries by the institution, the encoding means 23 (for example, including an aforementioned NBS circuit) may encrypt the applied data according to an algorithm of the type described in the aforementioned U.S. Pat. No. 3,938,091 or U.S. Patent Application Ser. No. 879,784, now issued as U.S. Pat. No. 4,198,619, or the like, to yield a new compiled code word or OFFSET II at the output 25 of the encoding means 23. This OFFSET II may be stored in files, for example, computer memory, printed lists, or the like, for later use with respect to transactions involving the individual and his card 9. Thus, the second level of interaction which produces OFFSET II required to produce a secured card 9 is under the security and control of the institution which may perform numerous checks and inquiries, later described herein, and which also retains the secrecy of its own secret key 21.
In many applications, the OFFSET II may be used directly to prepare a card 9 by encoding the card 9 magnetically, optically, mechanically, etc., in known manner with the account number and OFFSET II. Subsequent use of the card 9 thus produced in connection with a secured transaction would require entry of the individual's PIN 11 at the time of a transaction, the account number 13 (omitting an operator's I.D.), the bank I.D. 15 and the bank secret key 21, all in the manner previously described to produce an OFFSET II according to the same algorithms and encryption schemes used in the initial sign-on transaction, which OFFSET II could then be compared in known manner with the OFFSET II detected from the card 9 as the basis for determining whether the authorized individual who is unique to the card 9 is attempting to complete a secured transaction.
However, in certain applications requiring an additional level of secured interaction, the present invention may be used to ensure that no valid card can be duplicated. Thus, the supplier or actual issuer of cards (i.e., where different from the entity that generates OFFSETS I and II), may introduce an additional level of secrecy in producing the card 9. Each card 9 may be produced with a unique code or serial number which is different for each card. This unique code or serial number may be permanently implanted in each card mechanically, optically, magnetically, or the like, for subsequent detection by card transducer 27. The card serial number 29 thus detected is applied to encoding means 31 which may also contain an NBS circuit of the type previously described, for encrypting with OFFSET II and the account number in a known manner (for example, in accordance with the encryption algorithm disclosed in the aforecited U.S. Pat. No. 3,938,091 or U.S. Patent Application Ser. No. 879,784, now issued as U.S. Pat. No. 4,198,619) to produce a compiled code word, or OFFSET III at the output 33. A fully encoded card 9 may now be produced by card transducer 27 which can produce a record thereon mechanically, optically, magnetically, or the like, in known manner (but without altering the card serial number) from OFFSET III, the account number, and optional data 35 such as expiration date, access restrictions, credit limits, etc. The OFFSET III which may be of fixed length and which is unique for one card, one individual and one bank, may be recorded on the card 9 in location preceding the account number for subsequent detection and comparison during completion of a secured transaction. Movement of a card 9 through card transducer 27 suffices to detect the serial number 29 of the card, and movement again (say, in the opposite direction) suffices to make the aforementioned recordings on the card 9 that are unique to the individual and institution.
During the completion of a subsequent secured transaction using the card 9, the authorized individual may enter his PIN 11 and his own assigned account number, and submit his card 9 for detection of its serial number and the recorded OFFSET III thereon. Substantially the same encryption of applied codes (except for the identifying code of a system operator during initial sign-on) may be completed to produce an OFFSET III for comparison with the OFFSET III detected from the card 9. Upon detection of parity of the newly-generated OFFSET III with the OFFSET III read out from the card 9, the transaction may be completed with respect to the individual whose PIN 11 was entered. Other subsequent code comparisons involving a recorded card 9 may also be performed using less than such full "on-line" checking capability, for example, under circumstances where the serial number of the card is implanted therein by secret means (as in certain European banking systems). Under such circumstances, the OFFSET II may be recorded on the card 9 for encoding "off-line" only with similar means as encoding means 31 upon the individual's entered account number and the OFFSET II and card serial number detected from the card. The OFFSET III thus produced must compare favorably with the OFFSET III read out from the card 9 to signal an authorized transaction.
Referring now to FIG. 2, there is shown a flow chart of the present invention which illustrates the logic expansion thereof for the protection of the institution at the aforementioned second level of interaction. Note that several checks and inquiries may be completed relative to the institution's operating personnel prior to generating the OFFSET II. For example, the institution may check the identification number 16 of the system operator against its file information to ensure that only its authorized personnel can operate the system. Upon successful completion of the first check, the operator's authority to assign an account number 18 may be checked against file information. Upon successful completion of this check, then account information may be checked 20 to determine, for example, that the assigned account number is one which the institution previously set up to be assigned. Also, the institution may check file information to ensure that a previously-assigned valid account number is not reassigned to another individual as well. Numerous other checks and inquiries may be made by the institution consistent with the security objectives it endeavors to meet and prior to encrypting in encoding means 23 the OFFSET I 19, the secret key 21 and account number, as previously described, to generate the OFFSET II.
Referring now to FIG. 3, there is shown a block diagram of the apparatus for operation according to FIGS. 1 and 2. The initial level of interaction with an individual newly signing on may be performed by an encrypting module 11, 13, 15, 17 having one keyboard upon which the individual may enter his PIN secretly and another keyboard upon which an operator or teller may enter an account number. The module may also have a bank identification number (e.g., route and transit number) included therein for encoding with the keyboard-supplied information. Such modules and their operation are described in the literature (see, for example, U.S. Pat. No. 3,938,091 and U.S. Patent Application Ser. No. 879,784, now issued as U.S. Pat. No. 4,198,619). Using an irreversible encryption algorithm of the type described, the module produces an OFFSET I of fixed word length independently of the length of the applied PIN and account number and bank identification number, and therefore preserves the security of the PIN for the assigned account number. The OFFSET I can be conveniently transmitted without security to the next station where an operator authorized to issue cards may complete the initial sign-on of an individual. Using a keyboard with display 24 coupled to a processor with memory files 26 in conventional configuration, an operator may enter his identification number and the OFFSET I and the account number for controlling the processor 26 to perform the initial check and inquiry and the subsequent encryption in encoding module 23, as described in connection with FIG. 2. The secrecy of the bank key 21 may be preserved by retaining it in volatile manner within the encoding module 23, 31. Thereafter, the processor 26 may control the card transducer 27 to detect the secretly and permanently recorded serial number on a card and to control the encoding module 23, 31 (may be the same module time shared) to produce and record the OFFSET III from the OFFSET II and the card detected serial number. In this way, the institution may complete the assignment of a recorded card 9 to an individual using the apparatus at diverse locations without compromising the security against card duplication and counterfeiting which the present system provides to the individual, the institution and even the card-issuing entity. | A card-encoding system and method preserves the security of the encoding process against duplication and counterfeiting of cards by securing the interactions under the control of the individual and then of the issuing institution. Multilevels of offset codes are generated in successive interactions so that attempted alteration, duplication, or counterfeiting of a coded card will be readily detectable using "off-line" card-checking apparatus. | 6 |
FIELD OF THE INVENTION
[0001] The present invention relates to stable compositions useful as primary standards and calibrators and controls comprising a cardiac troponin I (cTnI) such as native, recombinant, addition and deletion forms thereof, whether or not complexed with other troponin subunits such as TnC and/or TnT, in an inactivated human serum. The compositions are obtained by incubating troponin I or troponin I complexes with human serum. The compositions are characterized by an immunodetectability ratio of epitopes on the N-terminal segment to epitopes on the C-terminal segment substantially equivalent to that of cardiac troponin I in pooled, fresh serum from patients having undergone an acute myocardial infarction.
BACKGROUND OF THE INVENTION
[0002] Early and accurate assessment of suspected acute myocardial infarction is critically dependent on the sensitive and specific detection of intracellular cardiac muscle components released into the circulation, in order to distinguish a potentially lethal event in need of emergency measures from non-life threatening conditions such as angina and non-cardiac chest pain such as dyspepsia. Early electrocardiographic changes are neither adequately specific nor sensitive, and the medical profession has come to rely on serum biochemical markers of cardiac tissue injury for early diagnosis. Initially, the serum markers creatine kinase (CK) and specifically the cardiac CK-MB isoform were used; subsequently myoglobin as a more sensitive early indicator of cardiac damage became preferred. More recently, the cardiac troponin complex and its cardiac-specific subunits have come to be preferred as markers of myocardial damage because of their high specificity. A combination of these analytes, provides a high degree of diagnostic accuracy. If performed in the emergency room, an early and accurate diagnosis of myocardial damage significantly enhances the safe recovery of a suspected heart attack victim.
[0003] Troponin is a generic term used to identify a muscle protein integrally involved in the calcium-dependent regulation of muscle contraction. Troponin exists in both cardiac and skeletal muscle as a non-covalently-bound complex of three subunits; the isoforms troponin C, the calcium-binding subunit; troponin I, the inhibitory subunit; and troponin T, which locates the troponin complex on tropomyosin. Differences exist between the amino acid sequences of the cardiac muscle and skeletal muscle troponin isoforms, and these differences are exploited in diagnostic tests which specifically measure the cardiac isoforms of the troponin to assist the diagnostician in determining if a cardiac event has taken place.
[0004] cTnI is a low molecular weight protein containing about 210 amino acid residues. When a cardiac event such as myocardial infarction occurs, cTnI together with cTnC and cTnT are released into the blood stream as a result of deterioration of cardiac muscle. cTnI and cTnT isoforms are specific to cardiac tissue and detectably distinguishable from skeletal isoforms.
[0005] It has been suggested that serum troponin may exist as complexes usually referred to as CIT, IT, CI and CT complexes. Troponin subunits, especially cTnI, undergo various degradation reactions resulting in the formation of complexes that differ in molecular weight, tertiary structure and other physical and chemical characteristics. One of these characteristics is that epitopes which may originally have been exposed for reaction with selected antibodies are no longer so exposed and may even have been destroyed. See for example:
[0006] Bodor et al., Clin. Chem. 38(11), 2203 (1992)
[0007] Adams et al., Clin. Chem. 40(7), 1291 (1994)
[0008] Adams et al., Circulation 88(1), 101 (1993)
[0009] Adams et al., New England Journal of Medicine 330(10), 670 (1994)
[0010] A number of instruments have been designed and are commercially available to measure total cTnI in the blood of suspected heart attack victims. These include the Abbott AxSYM, the Dade OPUS, the Bayer IMMUNO-1, the Beckman ACCESS, and the Dade STRATUS. Each of these instruments measure cTnI be reacting different epitopes with different antibodies. One, for example, measures an epitope near the C-terminus of the molecule whereas another measures an epitope near the middle of the molecule or a the N-terminus.
[0011] The epitope measured or the antibodies employed do not detract from the accuracy of the instrument or its sensitivity. However, it does mean that each instrument has a different reference range and each has a different value indicative of a positive reading. For example, on the Dade STRATUS a positive test is recognized by a value of >1.5 ng/ml. On the ACCESS device, it is >0.2 and on AxSYM it is >2.0. These variations sometimes cause confusion if a patient is moved from one hospital to another or the technician is working on different instruments.
[0012] Other problems with utilizing cTnI as an indication of cardiac damage is the rapid degradation of the molecules and the fact that its concentration varies among different patients. The problems can be alleviated by utilizing fresh samples. However, these are difficult to obtain because patients present at different times after the onset of chest pain and the variation amongst patients is never known with any degree of confidence.
[0013] The art has sought to deal with the problems by utilizing pooled patients' serum to calibrate the various instruments. The solution has been unsatisfactory because the pooled sample degrades during storage even at low temperatures.
[0014] The art has long searched for some method of standardization so that the reference ranges on the different instruments would be the same. The invention described and claimed herein makes such standardization possible. For convenience, the term cTnI will be used in the Specification and Claims to refer to natural cTnI, as well as addition and deletion analogs thereof whether isolated from a natural source or produced by recombinant techniques. It will include also complexes of natural cTnI and such analogs with the other troponin isoforms, cTnC and cTnT. It will refer also to those analogs of natural cTnI which have been extended at either end by the addition of other amino acid segments. The criteria for recognizing a troponin useful in this invention is that it will act like natural cTnI to achieve the novel, stable compositions of the invention.
[0015] The ratio of immunodetectability is determined by a separate determination of a detectable epitopes in the area of the C-terminus and the area of the N-terminus of the molecule. Although separate determinations are made, they are made on the same sample at the same time. The epitope on the N-segment is measured with the STRATUS device. The epitope on the C-segment is measured with the ACCESS device.
DESCRIPTION OF THE INVENTION
[0016] The compositions of this invention when utilized in diagnostic procedures perform in a fashion similar to fresh patient serum samples even after long storage periods. They thus offer prolonged stability and when prepared from recombinant cTnI and fresh serum, better lot-to-lot consistency and unlimited availability.
[0017] Various forms of cardiac troponin I may be used in the present invention, including but not limited to native troponin I, recombinant troponin I, synthetic troponin I, and various addition or deletion forms thereof. Synthetic proteins may be made by, for example, solid-phase synthesis. An example of a recombinant form of cardiac troponin I with a 6-amino acid leader sequence is disclosed in U.S. Pat. No. 5,834,210, incorporated herein by reference. Other forms may be used which do not detract from the purposes herein.
[0018] The stable standardization compositions of this invention are obtained by mixing a cTnI with human serum at selected concentrations and allowing the mixture to incubate at about 35° C. to about 44° C., preferably 35° C. to 37° C. until the desired equilibrium composition has been obtained. The desired equilibrium composition has an immunodetectability ratio of the N-terminus to the C-terminus of cTnI substantially equivalent to that of pooled, fresh serum from acute myocardial infarction patients.
[0019] Typically the concentration of cTnI will be from about 20 to about 100 ng/ml of serum, preferably 20 to 40 ng/ml, and most preferably about 30 ng/ml. This concentration is based on the determination of the purified cTnI utilizing the known Bradford assay with bovine serum albumin as the standard.
[0020] The incubation time is not critical. It may vary from about 3 to about 7 days depending upon the properties of the serum.
[0021] Optimum parameters for a specific form of cTnI and a specific serum can be readily determined by removing aliquots of the mixture and determining the immunodetectability ratio. Typically some variations from the above described parameters can be tolerated without unacceptably adverse results.
[0022] During the incubation time, the proteinases naturally present in the serum will act upon the mixture to cause the degradation of TnI until the desired ratio of immunodetectability is reached. At that time, the proteinases are substantially inactivated by heating or other means. Neither the temperature or the time is critical so long as they are not injurious to the mixture or its activity. Typically, the inactivation temperature is at least above about 37° C., but higher temperatures can be tolerated to decrease the time necessary for deactivation. The conditions will be from about 37° C. to 60° C., preferably 50° C. to 60° C., for from about 30 to 90 minutes. As indi variations are possible.
[0023] The proteinases may also be inactivated by known chemical means. One especially useful procedure comprises the use of inhibitor cocktails such as mixtures of phenylmethylsulphonylchloride (PMSF), ethylenediamine tetracetic acid, trans-epoxysuccinyl-L-leucylamidino (4-guanidino)butane and pepstatin. The inhibitors may be used at ambient temperature, i.e, around 20° C. to 30° C.
[0024] The extent of inactivation need only be that which results in a substantially stable product. Residual proteinase activity that does not affect the quality or utility of the product is tolerated.
[0025] Those skilled in the art will recognize that the achievement of stable compositions is not necessarily dependent on these proteinases which are naturally present in blood. The achievement of stable compositions can be accelerated by the addition of selected proteinases, such as native or recombinant proteinases that occur naturally in blood, as well as from other sources. Inactivation of these proteinases may be carried out by the appropriate methods for inactivation known to one of skill in the art.
[0026] It will also be recognized that those compositions having an immunodetectability ratio substantially equivalent to that of the pooled, fresh serum from acute myocardial infarction patients when measured on the STRATUS and the ACCESS machines, may manifest a different ratio when measured on other machines. Typically the ratio of the STRATUS and ACCESS values of the desired product is about 7:1. The criteria is that the immunodetectability of the epitope in the area of the N-terminus be appreciably higher than that in the area of the C-terminus. It appears that the rate at which the proteinases degrade the C-terminus region of the cTnI is higher than the rate at which the N-terminus region of the cTnI is degraded. Thus, with the passage of time, the number of N-terrninal epitopes in all of the molecules in the mixture becomes higher than the number of C-terminal epitopes.
[0027] In fact, it will be apparent that the activity of the proteinases can be terminated at substantially any point in time after the mixture has been formed and the resulting mixture will be stable. It has been observed, however, that after the passage of an appropriate period of time with a majority of patients undergoing or having undergone a cardiac event, the ratio of immunodetectable N-epitopes to C-epitopes based on the STRATUS and ACCESS values is approximately 7:1. Accordingly, in the practice of this invention it is desirable, but not essential to achieve the approximately same ratio. In practice, however, stable compositions in which the ratio is from about 4:1 to about 9:1 can be used in the practice of the invention, 6:1 to 8:1 being preferred. As noted above, the composition is intended to have substantially the same ratio as that of cTnI in patients serum.
[0028] It is not practical to isolate a formed stable composition from the blood of patients since there is appreciable variation in the ratio between patients and with the age of the sample. The problems for obtaining efficient and useful standards and calibrators results from this variation. The salient advantage of the novel compositions of this invention is that they are stable for an extended period of time and behave like fresh human serum. It is therefore possible for manufacturers of assay devices such as those mentioned above to use the compositions to develop those devices to validate their assays compared to other devices with confidence and to utilize accurate quality control procedures.
[0029] The present invention is also directed to an assay kit for determining the level of troponin I in a patient sample relative to a troponin I standard comprising means for measuring troponin I in said sample; and a troponin I composition of claim 1. Means for detecting troponin I may take the form of any of the various assay kits for troponin I such as those described herein. By use of the troponin I standard of the present invention in such assays, the levels of troponin I in patient samples may be standardized, improving the diagnostic utility of the analyte as well as permitting the establishment of normal and abnormal ranges both within and across laboratories.
[0030] The following examples are given by way of illustration only.
EXAMPLE 1
Preparation of a Serum-Processed Troponin I Standard
[0031] A stable troponin I standard was prepared in accordance with the present invention by incubating under sterile conditions 30 ng/ml of recombinant troponin I consisting of a noncovalent complex of recombinant troponin C and a modified recombinant human cardiac troponin I expressed with a 6 amino acid leader sequence at the N-terminus (as described in U.S. Pat. No. 5,834,210). At the times indicated in Table 1, below, samples were taken for analysis in the STRATUS and ACCESS troponin I immunoassays. As noted above, the STRATUS assay uses two monoclonal antibodies which recognize the N-terminal portion of the troponin I molecule; the ACCESS assay uses two monoclonal antibodies which recognize the C-terminal portion of the troponin I molecule. During proteolytic degradation, loss of C-terminal detection results in an increase in the ratio of the STRATUS to the ACCESS (“S/A”) assay results.
TABLE 1 Immunodetectability (in ng/ml) of troponin I after incubation in human serum Time (hrs): 0 4 7 16 24 48 72 144 30 ng/ml troponin I-troponin C complex* STRATUS 11.85 23.85 26.70 27.50 35.13 28.25 26.15 21.55 (S) ACCESS 15.84 15.65 13.48 12.94 15.65 8.1 6.49 3.54 (A) S/A 0.75 1.52 1.98 2.13 2.24 3.49 4.03 6.09 30 ng/ml of troponin C-troponin I-troponin T complex* STRATUS 19.10 29.95 35.95 34.75 35.45 36.05 33.70 25.85 (S) ACCESS 24.14 24.86 21.53 19.73 15.14 12.76 9.99 5.06 (A) S/A 0.79 1.20 1.67 1.76 2.34 2.83 3.37 5.11
[0032] As shown in Table 1 above for both a complex of troponin I and troponin C, as well as a complex of troponin C, I and T, during incubation with serum, the C-terminus of troponin I degrades, as shown by the decreasing values in the ACCESS assay, in contrast to the relative stability of the N-terminus as shown by the values in the STRATUS assay.
EXAMPLE 2
Stability of the Troponin I Composition
[0033] The stability of the troponin I compositions of the present invention was evaluated by storage at −20 C., followed by assay in both the STRATUS and ACCESS troponin I assays. Four concentrations of troponin I were used at the levels shown in the Tables. The results using a troponin I-troponin C complex are shown in Table 2, and the results with a troponin C-I-T complex in Table 3.
TABLE 2 Stability of troponin I-troponin C Level day 0 day 10 day 121 Stratus 1 0.75 0.65 0.90 2 1.60 1.40 1.70 3 3.25 3.05 3.40 4 6.35 6.25 6.30 Access 1 0.123 0.141 0.187 2 0.243 0.240 0.341 3 0.451 0.468 0.631 4 0.992 0.827 1.180
[0034] [0034] TABLE 3 Stability of troponin I-troponin C - troponin T Level day 0 day 10 day 121 Stratus 1 0.70 0.60 0.60 2 1.65 1.40 1.80 3 2.95 2.55 3.10 4 6.20 5.35 5.90 Access 1 0.120 0.127 0.158 2 0.222 0.241 0.372 3 0.433 0.473 0.688 4 0.875 0.826 1.102
EXAMPLE 3
[0035] Immunodetectability compared to pooled patient serum
[0036] The equivalence or similarity between the TnI composition of the present invention and that of pooled fresh acute myocardial infarction (AMI) patient serum was evaluated by STRATUS, ACCESS, OPUS and CARDIAC STATUS kits. Two lots of the TnI composition of the invention and two lots of the TnI composition of the pooled, fresh AMI patient serum, both in four concentrations, were compared in terms of immunodetectability by the above mentioned TnI assays. The results are shown in the following Table 4.
TABLE 4 I. Troponin I composition of the present invention Stratus Access STATus Opus Lot # 1 Level (ng/ml) (ng/ml) S/A* (qualitative) (ng/ml) 1 0.80 0.152 5.26 Negative 1.29 2 1.50 0.266 5.64 Trace 2.51 3 3.10 0.501 6.19 Positive 5.39 4 6.00 1.068 5.62 Positive 9.82 Ave: 5.68 Stratus Access STATus Opus Lot # 2 Level (ng/ml) (ng/ml) S/A* (qualitative) (ng/ml) 1 0.80 0.096 8.33 Negative 1.12 2 1.60 0.262 6.11 Trace 2.46 3 3.20 0.553 5.79 Positive 5.09 4 6.50 0.871 7.46 Positive 11.10 Ave: 6.92 II. TnI calibrator derived from freshly pooled AMI patient serum Stratus Access STATus Opus Lot # 1 Level (ng/ml) (ng/ml) S/A (qualitative) (ng/ml) 1 0.85 0.099 8.59 Negative n/a 2 1.80 0.257 7.00 Trace n/a 3 3.15 0.414 7.61 Positive n/a 4 6.80 0.995 6.83 Positive n/a Ave: 7.51 Stratus Access STATus Opus Lot # 2 Level (ng/ml) (ng/ml) S/A* (qualitative) (ng/ml) 1 n/a n/a n/a n/a 2 7.20 0.856 8.41 Positive 11.36 3 10.65 1.220 8.73 Positive 18.85 4 26.75 3.730 7.17 Positive 54.10 Ave: 8.10
[0037] While the invention has been described and illustrated herein by references to the specific embodiments, various specific material, procedures and examples, it is understood that the invention is not restricted to the particular material, combinations of material, and procedures selected for that purpose. Indeed, various modifications of the invention in addition to those described herein will become apparent to those skilled in the art from the foregoing description and the accompanying figures. Such modifications are intended to fall within the scope of the appended claims.
[0038] Various publications are cited herein, the disclosures of which are incorporated by reference in their entireties. | The present invention relates to stable compositions useful as primary standards and calibrators and controls comprising a cardiac troponin I (cTnI) such as native, recombinant, addition and deletion forms thereof, whether or not complexed with other troponin subunits such as TnC and/or TnT, in an inactivated human serum. The compositions are obtained by incubating troponin complexes with human serum. The compositions are characterized by an immunodetectability ratio of epitopes on the N-terminal segment to epitopes on the C-terminal segment substantially equivalent to that of pooled, fresh serum from acute myocardial infarction patients. | 8 |
BACKGROUND
This description relates to supporting an electronic device.
Stands for supporting audio, video, and other electronic equipment sometimes include legs. Tripods, for example, have three legs connected at a central hub on which the electronic equipment is mounted. The lower free ends of the legs are splayed out to provide stable support. In some tripods, all three legs can be collapsed by pivoting at the central hub, sometimes in a coordinated motion.
SUMMARY
In general, in an aspect, a receptacle supports an electronic device; support legs connected to the receptacle are movable in a common plane between a first, retracted position and a second, extended position; and a coupling translates movement of one of the support legs between the positions to corresponding movement of at least another one of the support legs.
Implementations may include one or more of the following features. The receptacle inhibits insertion of the electronic device into the receptacle when the support legs are in the first, retracted position. Movement of the support legs between the extended position and the retracted position is inhibited when the electronic device is supported by the receptacle. The coupling includes: a link plate and linkage arms, and each of the linkage arms has a first end mounted to the link plate and a second end mounted to a corresponding one of the support legs. The link plate is linearly displaceable relative to the receptacle. The support legs lie in a common plane. The electronic device includes a loudspeaker. The support includes electronics operable to control one or more aspects of the electronic device. The electronics include one or more of an audio control circuit, an amplifier, and an equalizer. The electronics include an electrical connector on the receptacle, and the electronics are configured to communicate with the electronic device through the electrical connector. The receptacle is keyed to the electronic device.
In general, in an aspect, an electronic device is supported by extending one of multiple support legs of a support device from a retracted position toward an extended position to cause corresponding and co-planar movement of at least one other support leg, and a mating electronic device is inserted into a corresponding receptacle of the support device.
In general, in an aspect, a receptacle to support an electronic device; support legs are movable in a common plane between a first, retracted position and a second, extended position; and a lockout mechanism limit operations of the device based on a condition of the receptacle.
Implementations may include one or more of the following features. The lockout mechanism prevents insertion of the electronic device into the receptacle when the support legs are in the first, retracted position. The lockout mechanism includes a stopper that extends into the receptacle when the support legs are in the first, retracted position. The lockout mechanism prevents movement of the support legs from the extended position toward the retracted position when the electronic device is disposed in the receptacle. A deployment mechanism responds to movement of a first one of the support legs between the positions by causing corresponding movement of another one of the support legs.
These aspects and features and other combinations of these and other aspects and features can be expressed as methods, apparatus, systems, and as means for performing functions, and in other ways.
Other features and advantages will be apparent from the description and the claims.
DESCRIPTION
FIG. 1 is a perspective view of a support stand and an electronic device.
FIG. 2A through 2C are bottom, top, and perspective views of a support stand.
FIG. 3A is a bottom perspective view of a support stand.
FIG. 3B is a partial exploded perspective view of a portion of a support stand.
FIGS. 4A and 4B are top perspective views of portions of a support stand.
FIG. 5 is a top perspective view of a portion of a support stand.
DETAILED DESCRIPTION
Referring to FIGS. 1 , 2 A, 2 B, and 2 C, a support stand 10 for an electronic device 20 (e.g., a floor standing personal amplification system including a line array loudspeaker such as sold under the trade name Cylindrical Radiator® by Bose Corporation of Framingham, Mass.; and other described in United States patent application publications 2004/0264726, filed Jun. 30, 2003, and 2004/0264716 filed Jun. 30, 2003, both of which are incorporated here by reference in their entirety) includes an oblong base 12 and a plurality of (four in the example) support legs 30 at the four corners of the base. Each of the support legs 30 is moveable, relative to the base 12 , between a retracted position ( FIG. 2A ) and an extended position ( FIG. 2B ). All four support legs 30 are mechanically linked to induce synchronized movement of all four support legs 30 in a common plane so that movement of one of the support legs 30 between the two positions causes simultaneous corresponding movement of the other support legs 30 as indicated by arrows 31 in FIG. 2C . In the retracted position each of the legs lies in a position substantially within the footprint defined by the base. Thus, when the legs are in the retracted position, the stand is more compact and can be more easily transported and stored. When the stand is to be used, the support legs 30 are moved to the extended position and lie in a common plane close to the ground, providing stable support to the stand and the electronic device mounted on it. For storage or transport, the legs are moved to their retracted position.
As shown, for example, in FIGS. 3A-3B , the base 12 is an assembly that includes a chassis 14 (e.g., a metal chassis) having a central support bar 16 , overhanging ridges 18 extending laterally from the central support bar 16 , and a cover plate 11 ( FIG. 3B ). The support legs 30 (each of which is made of plastic and/or metal) are mounted for rotation at points 13 a - d on the overhanging ridges 18 at the corners of the base. As shown in FIG. 3B , each of the support legs 30 includes a cylindrical pivot 32 that projects from a first surface 33 at one end 34 of the leg 30 . Each pivot 32 extends through corresponding holes 15 , 17 in the cover plate 11 and overhanging ridges 18 of the chassis 14 . A mounting plate 35 is attached to the tip of the cylindrical pivot 32 (i.e., using a mechanical fasteners 40 to transfer rotation of the support leg 30 into rotation of the mounting plate 35 ). Bushings 41 and 42 are provided at the mating surfaces between the support leg 30 , the chassis 14 , and the mounting plate 35 to permit free rotation. The mounting plate 35 includes a protuberance 36 which forms a connection with a deployment mechanism 50 ( FIGS. 4A and 4B ) to transfer rotation of the support leg 30 to the deployment mechanism 50 .
Referring to FIGS. 4A and 4B , the deployment mechanism 50 , on the other side of chassis 14 from the legs, provides for synchronized movement of the support legs 30 . Specifically, the deployment mechanism 50 includes a link plate 52 mounted on the topside of the cover plate 11 of the chassis 14 using shoulder screws 102 , 104 that ride in slots 106 , 108 , and four linkage arms 54 , one for each leg. Each of the linkage arms 54 includes one end 53 attached to the link plate 52 using a nut 110 and another end 55 attached to the protuberance 36 of the mounting plate 35 of a corresponding one of the support legs 30 . When one of the support legs 30 is rotated (as indicated by arrow 120 of FIG. 4B ) it drives the end 55 of the corresponding linkage arm 54 radially about point 13 a , as indicated by arrow 122 . Because the end 55 is mounted off-center from the center of rotation of the support leg 30 , rotation of the leg 30 is translated into a cam-like movement of the linkage arm 54 at the end 55 , which, in turn, exerts a force on the link plate 52 at the end 53 causing linear displacement of the link plate 52 , as indicated by arrow 124 . The linear movement of the link plate 52 exerts a force (in the direction of arrow 124 ) at ends 53 of the other linkage arms 54 , which, in turn, is transferred to the ends 55 resulting in rotation (i.e., about points 13 b - 13 d , as indicated by arrows 126 , 127 , 128 ) of the other support legs 30 .
The support stand 10 also includes a receptacle 60 to mate with and support a bottom end 114 ( FIG. 1 ) of the electronic device 20 ( FIG. 1 ). The receptacle 60 is mounted to the chassis 14 and is shaped to conform roughly to the shape of the outer surface of the bottom of the electronic device 20 . The receptacle 60 can include keys 61 to form lock-and-key type interfaces with lock surfaces (not shown) on the bottom end of the electronic device 20 ; i.e., to require the electronic device 20 to be supported in a particular orientation.
The support stand 10 can also include a lockout mechanism 70 for preventing or inhibiting insertion of the electronic device 20 into the receptacle 60 unless and/or until the support legs 30 are in the fully extended position ( FIG. 4B ), and preventing or inhibiting retraction of the support legs 30 (i.e., from the extended position ( FIG. 4B ) toward the retracted position ( FIG. 4A )) unless and/or until the electronic device 20 is removed from the receptacle 60 . As illustrated in FIGS. 4A and 4B , the lockout mechanism 70 is connected to the link plate 52 and operated by movement of the link plate 52 as the support legs 30 are moved between the retracted and extended positions. As shown, for example, in FIG. 4A , the lockout mechanism 70 includes a stopper 72 which extends into the receptacle 60 (i.e., through aperture 62 ) when the support legs 30 , and deployment mechanism 50 , are in the retracted position ( FIG. 4A ), thereby preventing insertion of the electronic device 20 . When the support legs 30 are moved into the extended position, as shown in FIG. 4B , the corresponding movement of the link plate 52 displaces the stopper 72 to a position outside of the receptacle 60 , allowing the electronic device 20 to be inserted. Furthermore, the presence of the electronic device 20 in the receptacle 60 prevents the stopper 72 from reentering the receptacle 60 and, as result, prevents retraction of the support legs 30 as long as the electronic device is inserted.
As shown in FIG. 5 , the support stand 10 can also include electronics 80 mounted on two circuit boards 81 , and 83 , for example, an audio control circuit, an amplified, and/or an equalizer to be used with the electronic device 20 . The control electronics 80 can include an electrical connector 82 , shown in FIG. 2B , disposed at a bottom surface 64 of the receptacle 60 . The electrical connector 82 provides an interface for communication with the electronic device 20 (e.g., through a mating connector).
As shown in the drawings and described above, the support stand 10 is arranged as multiple layers of subassemblies. For example, the deployment mechanism 50 is disposed between the circuit boards 81 , and 83 of the electronics 80 and the cover plate 11 of the chassis. Similarly, the chassis, or at least the cover plate 11 and overhanging ridges 18 of the chassis 11 , form a layer between the support legs 30 and the deployment mechanism.
Other embodiments are within the scope of the following claims.
For example, in some embodiments, the support stand can include a user interface 86 ( FIGS. 1 and 2B ) (e.g., in communication with the control electronics) for controlling operation of the electronic device based on a user input. In some implementations, the user interface can include an input/output (I/O) panel for communication with one or more secondary devices, such as microphones and musical equipment (e.g., instruments, recording equipment, etc.). The I/O panel can include, for example, a primary input channel connection for receiving an input signal from a secondary device; an input trim control for input level adjustment for the secondary device; a preset selector (e.g., for selecting between predetermined parameter settings, each specific to a corresponding secondary device); a line out connector (e.g., for connecting the electronics to external recording equipment); channel insert jacks (e.g., for connecting the electronics to digital effects processors; one or more I/O jacks for linking the electronics of multiple support stands together (i.e., for communication between two or more support stands); a remote connector for connecting the electronic to a remote control; a main power connector (e.g., for connecting to a 120V, 15V power source; and/or a power on/off switch for switching electrical power to the electronics on and off.
While the support stands described above include support legs that are rotatable between the retracted and extended positions, other embodiments can include support legs that are movable linearly between extended and retracted positions. For example, in some embodiments, the support legs can include telescoping members that are extendable, in a substantially linear direction, outward from chassis (and collapsible inward, towards the chassis).
In some implementations, the base 12 can include a housing 15 ( FIGS. 1 and 2B ) that overlies the electronics and/or deployment mechanism. In some embodiments, the housing 15 and/or chassis 14 include(s) a carry handle 17 ( FIGS. 1 and 2B ) for portability. In some implementations, the carry handle 17 is disposed on the support stand so as to urge the link plate towards the retracted position when the support stand is lifted by the carry handle 17 .
In some embodiments, the electronics include fans 85 ( FIG. 5 ) to provide an air flow across the electronics (i.e., for convective cooling of electronic components). The chassis and/or housing can also include vents 90 (e.g., defined by the overhanging ridges, as shown, for example, in FIG. 3B ) to allow for passage of an air flow through the support stand. | Among other things, a receptacle supports an electronic device; support legs connected to the receptacle are movable in a common plane between a first, retracted position and a second, extended position; and a coupling translates movement of one of the support legs between the positions to corresponding movement of at least another one of the support legs. | 5 |
FIELD OF THE INVENTION
The present invention relates to a process for the production of an electromechanical, for example piezoelectric, converter, to electromechanical converters, and to the use thereof.
BACKGROUND OF THE INVENTION
The ability of some materials to generate an electric potential in response to applied mechanical stress is referred to as piezoelectricity. Established piezoelectric materials are lead zirconium titanate (PZT) and fluorinated polymers such as polyvinylidene fluoride (PVDF). Piezoelectric behaviour has also been observed in foamed, closed-pore polypropylene (PP). In order to achieve piezoelectricity, such a polypropylene foam is charged in a high electric field. As a result, electrical breakdowns occur within the pores, generating macrodipoles and polarising the material macroscopically. Such polypropylene ferroelectrets can have a piezoelectric coefficient of several hundred picocoulombs per Newton. In order further to increase the sensitivity of the sensor action, multilayer systems comprising a plurality of foams stacked one above the other have been developed.
Gerhard et al. (2007 Annual Report Conference on Electrical Insulation and Dielectric Phenomena, pages 453 to 456) describe a three-layer ferroelectret in which a polytetrafluoroethylene film provided with a plurality of homogeneous through-holes by mechanical or laser-based drilling is arranged between two homogeneous fluoroethylenepropylene films. However, the incorporation of through-holes by mechanical or laser-based drilling is complex and unsuitable for large-scale production. For example, as is also disclosed in the above-mentioned source (p. 454), the perforated layer must be chemically cleaned after the mechanical or laser-based drilling in order to remove metal residues (burrs) or organic residues.
The three-layer ferroelectret disclosed in Gerhard et al. is produced by a lamination process. In this process, the polytetrafluoroethylene film provided with holes is joined to the fluoroethylenepropylene films by passing the layers between two heated rotating cylinders under high pressure and at elevated temperature (310° C.).
It would be desirable to provide a process for the production of an electromechanical, for example piezoelectric, converter that is suitable for large-scale production.
DETAILED DESCRIPTION OF THE INVENTION
There is therefore proposed according to the invention a process for the production of an electromechanical, for example piezoelectric, converter, which process comprises the following steps:
A) applying a first polymer layer ( 2 ; 2 a ) having holes ( 3 ; 3 a ) to a first continuous polymer layer ( 1 ; 1 a ) by means of a printing and/or coating process, with the exception of a lamination process; B) applying a covering ( 4 ; 1 b , 2 b ) to the first polymer layer ( 2 ; 2 a ) having holes ( 3 ; 3 a ) so that the holes ( 3 ; 3 a ) of the first polymer layer ( 2 ; 2 a ) having holes ( 3 ; 3 a ) are closed to form voids ( 5 ); and C) joining the covering ( 4 ; 1 b , 2 b ) to the first polymer layer ( 2 ; 2 a ) having holes ( 3 ; 3 a ),
wherein
in a process step D), an electrode ( 6 a ) is applied to the outside of the first continuous polymer layer ( 1 , 1 a ) and an electrode ( 6 b ) is applied to the outside of the covering ( 4 ; 1 b , 2 b ), the electrodes ( 6 a , 6 b ) being applied independently of one another or simultaneously before or after one of steps A) to C), and in a process step E), the arrangement obtained after process step C) or after a process step following process step C) is charged.
By means of the process according to the invention, electromechanical converters can advantageously be produced on a large scale.
Within the scope of the invention, coating processes are understood in particular as being not laminating processes as are disclosed, for example, in Gerhard et al.
Furthermore, the holes can have many different shapes in the process according to the invention. The shape of the hole is therefore not limited to a cylindrical shape with a circular cross-sectional area. Moreover, the process according to the invention offers the possibility of combining holes of different shapes. In this manner it is advantageously possible on the one hand to maximise the total void volume of the resulting voids. On the other hand, the electromechanical, in particular piezoelectric, properties of the electromechanical converters produced by the process according to the invention can be adjusted by the choice of hole shape, arrangement and/or distribution.
In addition, burrs and other sharp-edged hole surface irregularities are avoided by the process according to the invention. On the one hand this has an advantageous effect on the electromechanical, in particular piezoelectric, properties; on the other hand it reduces the outlay in the production of the converter because the working step of removing such irregularities is unnecessary.
The polymer layer having holes can advantageously make the electromechanical converter that is to be produced softer along its thickness, thus lowering its modulus of elasticity, permitting a polarisation process in the resulting voids and/or separating load layers formed in the continuous polymer layers after the charging process.
In an embodiment of the process, the covering comprises a second polymer layer having holes and a second continuous polymer layer, the second polymer layer having holes being arranged on the second continuous polymer layer. In particular, the covering can consist of a second polymer layer having holes and a second continuous polymer layer.
In a further embodiment of the process, the covering is a third continuous polymer layer.
In a further embodiment of the process, the covering is produced by applying a second polymer layer having holes to a second continuous polymer layer by means of a printing and/or coating process.
The material of the first polymer layer having holes can be partially hardened, for example partially dried and/or partially crosslinked and/or partially solidified and/or partially crystallised, after it has been applied to the first continuous polymer layer. Likewise, the material of the second polymer layer having holes can be partially hardened, for example partially dried and/or partially crosslinked and/or partially solidified and/or partially crystallised, after it has been applied to the second continuous polymer layer. In particular, the material of the first polymer layer having holes, after it has been applied to the first continuous polymer layer, and/or the material of the second polymer layer having holes, after it has been applied to the second continuous polymer layer, can be partially hardened, for example partially dried and/or partially crosslinked and/or partially solidified and/or partially crystallised, in such a manner that its viscosity is increased as compared with its viscosity on application to the continuous polymer layer. In this manner, the dimensional stability of the holes can be improved on the one hand. On the other hand, only partial hardening offers the possibility of joining the first polymer layer having holes to the third continuous polymer layer or to the second polymer layer having holes, by further, in particular complete, hardening of the material.
In a further embodiment of the process, therefore, joining of the first polymer layer having holes to the covering is effected by only partial hardening of the material of the first polymer layer having holes, after it has been applied to the first continuous polymer layer, and/or only partial hardening of the material of the second polymer layer having holes, after it has been applied to the second continuous polymer layer, and further, in particular complete, hardening of the material of the first polymer layer having holes after the covering has been applied, and/or further, in particular complete, hardening of the material of the second polymer layer having holes after the covering has been applied. Hardening can here be understood as meaning drying and/or crosslinking and/or solidification and/or crystallisation.
For example, it is possible to dry, for example thermally, the material of the first polymer layer having holes, after it has been applied to the first continuous polymer layer, and/or the material of the second polymer layer having holes, after it has been applied to the second continuous polymer layer, and to carry out crosslinking only after the covering has been applied.
A further example is to use a material that solidifies and/or crystallises amorphously, in particular a polymer, for example a polyurethane, for the first polymer layer having holes and/or the second polymer layer having holes. The material that solidifies and/or crystallises amorphously can be applied, for example, in the form of a dispersion to the first or second continuous polymer layer to form the first or second polymer layer having holes. The material that solidifies and/or crystallises amorphously can partially solidify and/or crystallise amorphously, for example, after being applied to the first or second continuous polymer layer, and can completely solidify and/or crystallise amorphously after the covering has been applied and thereby join the first polymer layer having holes to the covering. The material that solidifies and/or crystallises amorphously can, however, also completely solidify and/or crystallise amorphously after being applied to the first or second continuous polymer layer and be crosslinked after the covering has been applied, the first polymer layer having holes being joined to the covering. Furthermore, the material that solidifies and/or crystallises amorphously can completely solidify and/or crystallise amorphously after being applied to the first or second continuous polymer layer and, after the covering has been applied, can be heated to a temperature at which the material that solidifies and/or crystallises amorphously softens and/or melts, the third continuous polymer layer, or the other polymer layer having holes, being wetted, the structure of the polymer layer having holes being retained and, after cooling to a lower temperature, the first polymer layer having holes being joined to the covering.
The material of the first and/or second polymer layer having holes can be crosslinked, for example, thermally, by irradiation with ultraviolet light, by irradiation with infrared light and/or by drying. In particular, when a layer comprises polymers having low UV stability, such as polycarbonates, crosslinking can take place thermally, by irradiation with infrared light or by drying.
In a further embodiment of the process, application of the first polymer layer having holes and/or application of the second polymer layer having holes takes place by the following coating or printing processes: application by doctor blade, spin coating, dip coating, spray coating, curtain coating, slot-die coating, flexographic printing, gravure printing, tampon printing, digital printing, thermal transfer printing, porous printing, in particular relief printing, flat printing, offset printing and/or screen printing, and/or a roller application process, for example using roller applicators for hot-melt adhesives from Hardo Maschinenbau GmbH (Bad Salzuflen, Germany).
Application of the first polymer layer having holes and/or application of the second polymer layer having holes can be carried out, for example, by application by doctor blade, spin coating, dip coating, spray coating and/or curtain coating in combination with matrices or templates.
In a further embodiment of the process, application of the first polymer layer having holes and/or application of the second polymer layer having holes is carried out by means of a screen printing process.
Application of the first polymer layer having holes and/or application of the second polymer layer having holes can be carried out using a heated, for example electrically heated, screen, in particular a screen printing fabric. Heated screens for screen printing are supplied, for example, by Koenen GmbH (Ottobrunn, Germany) under the trade name Hot Screen.
As screen printing pastes for heated screens there can be used, for example, thermoplastic substances, such as reactive and non-reactive hot-melt adhesives based on polyurethane, polyester and/or polyamide, in particular hot-melt pastes, or screen printing pastes that comprise high-boiling solvents and/or that dry under ultraviolet light.
The thermoplastic substances, or hot-melt pastes, are preferably solid at room temperature and, at the temperatures to which the screen is heated, for example from ≧60° C. to ≦80° C., reach a viscosity that is comparable with that of conventional screen printing pastes, for example from ≧1000 mPa·s to ≦20,000 mPa·s. The addition of solvents is not necessary with such hot-melt pastes. The thermoplastic substances cool on contact with the continuous polymer layer and can thus remain sharp-contoured. In addition to sharp-contoured structures, the use of a heated screen and a thermoplastic substance has the advantage that a drying process can be omitted.
Screen printing pastes that comprise high-boiling solvents and/or that dry under ultraviolet light can be applied using a heated screen, in particular a screen printing fabric, and optionally a heated doctor blade. Heating the screen lowers the viscosity of the paste. When the paste comes into contact with the continuous polymer layer, the paste cools and its viscosity increases. This has the advantage that the contour sharpness can be increased. Depending on the fineness of the screen printing fabric, low viscosity pastes can optionally also be used. The fineness of the fabric is understood as meaning the number of threads per centimeter. For example, screen printing fabrics having a thread count of at least 120 threads per centimeter, in particular at least 150 threads per centimeter, can be used.
In order to prevent the paste from cooling on printing when a heated screen is used, and in order to achieve optimum processability during printing, the printing blade and/or flood coater can be heated.
In order to increase the thickness of the polymer layers having holes, a plurality of prints can be executed one above the other. The material of the first or second polymer layer having holes can be partially or completely hardened, for example dried and/or crosslinked and/or solidified and/or crystallised, between the individual printing steps. The prints can optionally be executed wet-on-wet.
While the structure of the polymer layer having holes can be applied directly by a printing process, the positions of the later holes in the above-described coating processes are initially covered or masked.
In a further embodiment of the process, application of the first polymer layer having holes and/or application of the second polymer layer having holes is carried out by transfer coating. “Transfer coating” is understood as meaning in particular that the polymer layer having holes is first formed on a transfer layer, for example a release paper or release film, by a printing and/or coating process and is then transferred to the continuous polymer layer and joined to the continuous polymer layer. Suitable printing and/or coating processes are the above-mentioned printing and/or coating processes. For joining to the continuous polymer layer there are suitable, for example, the above-mentioned procedures based on first only partial and then further, in particular complete, hardening and the above-mentioned lamination process. Transfer coating advantageously provides the possibility of spatially and temporally separating the production of the first and/or second polymer layer having holes and the joining of the layer(s) having holes to the continuous layers.
In a further embodiment of the process, the holes of the first polymer layer having holes pass right through the first polymer layer having holes, in particular in the direction of the continuous polymer layers, and/or the holes of the second polymer layer having holes pass right through the second polymer layer having holes, in particular in the direction of the continuous polymer layers. In this manner, the voids formed on completion of the process according to the invention are in contact on one side with one (first) continuous polymer layer and on the other side with the other (second or third) continuous polymer layer. This in turn has an advantageous effect on the electromechanical behaviour of the electromechanical energy converter that is produced.
Within the scope of the present invention, the first and/or second polymer layer having holes can be formed either by printing and/or coating the first or second continuous polymer layer with a contiguous polymer layer having holes or by printing and/or coating the first or second continuous polymer layer with identical or different, isolated or interconnected structures, for example structures having a small surface area, such as points and lines, for example curved or straight, individual or crossed lines or circumferential lines of geometric figures, for example a circular line or a circumferential line of a cross, or structures having a larger surface area, such as filled rectangles, circles, crosses, etc. The size and layer thickness of the structures is preferably such that the continuous polymer layers cannot touch one another and/or the total void volume obtained after manufacture is as large as possible. In the electromechanical converter, the first and/or second polymer layers having holes can each have a layer thickness of, for example, from ≧1 μm to ≦800 μm, in particular from ≧10 μm to ≦400 μm. If only a first polymer layer having holes is applied during production of the electromechanical converter, then the first polymer layer having holes in the electromechanical converter can have in particular a layer thickness of from ≧1 μm to ≧800 μm, for example from ≧10 μm to ≦400 μm. If both a first and a second polymer layer having holes is applied during production of the electromechanical converter, then the overall layer thickness of the first polymer layer having holes and the second polymer layer having holes in the electromechanical converter can be from ≧1 μm to ≦800 μm, for example from ≧10 μm to ≦400 μm. Depending on the printing and/or coating processes and parameters used in the production of the electromechanical converter, it is possible—for example when using solvent-containing printing inks, inks, pastes, formulations, lacquers or adhesives—for the layer thickness of the first and/or second polymer layer having holes, directly after application of the polymer layer having holes to the continuous layer, to be greater than or even markedly greater than the layer thickness of the resulting polymer layer having holes in the electromechanical converter. The layout, the printing process parameters and/or the coating process parameters are preferably such that the polymer layers having holes do not have any voids, in particular gas inclusions, that are not in contact with the continuous polymer layers.
The holes of the first polymer layer having holes and the holes of the second polymer layer having holes can be so formed and arranged that, when the covering is applied, at least some of the holes of the first polymer layer having holes and some of the holes of the second polymer layer having holes overlap partly or completely.
In a further embodiment of the process, the holes of the first polymer layer having holes and the holes of the second polymer layer having holes are so formed and arranged that, when the covering is applied, a hole of the first polymer layer having holes and a hole of the second polymer layer having holes overlap partly or completely. This means that the holes of the first polymer layer having holes and the holes of the second polymer layer having holes are preferably so formed and arranged that, when the covering is applied, a hole of the first polymer layer having holes and a hole of the second polymer layer having holes form a common void. The holes of the first polymer layer having holes and the holes of the second polymer layer having holes are preferably so formed and arranged that a hole of the first polymer layer having holes and a hole of the second polymer layer having holes overlap completely. For example, the first and second polymer layers having holes can be congruent, in particular identical. It is thus possible to produce voids which are continuous from the continuous polymer layer on one side to the continuous polymer layer on the other side.
Within the scope of the present invention, at least some of the holes of the first polymer layer having holes and/or some of the holes of the second polymer layer having holes can have shapes having a cross-sectional area selected from the group consisting of substantially round, for example circular, elliptical or oval, polygonal, for example triangular, rectangular, trapezoidal, rhombic, pentagonal, hexagonal, in particular honeycomb, cross-shaped, star-shaped and partially round and partially polygonal, for example S-shaped, cross-sectional areas. However, it is also possible for all the holes of the first polymer layer having holes and/or all the holes of the second polymer layer having holes to have shapes having a cross-sectional area selected from the group consisting of substantially round, for example circular, elliptical or oval, polygonal, for example triangular, rectangular, trapezoidal, rhombic, pentagonal, hexagonal, in particular honeycomb, cross-shaped, star-shaped and partially round and partially polygonal, for example S-shaped, cross-sectional areas, as well as shapes differing therefrom.
Within the scope of a further embodiment of the process, the holes of the first polymer layer having holes and/or the holes of the second polymer layer having holes are shaped and/or arranged in a honeycomb. A honeycomb shape and arrangement of the holes results on the one hand in a very large total void volume. On the other hand, a honeycomb shape and arrangement of the holes can have high mechanical stability.
The size of the cross-sectional areas can be the same or different in all the holes of a polymer layer having holes.
Within the scope of the process according to the invention, the holes in the first and/or second polymer layer having holes can be distributed both homogeneously and heterogeneously. In particular, the holes in the first and/or second polymer layer having holes can be distributed homogeneously. Depending on the field of application of the electromechanical converter that is to be produced, however, it can also be advantageous to distribute the holes in the first and/or second polymer layer having holes, in particular purposively, heterogeneously in a space-resolved manner.
The holes in the first and/or second polymer layer having holes can optionally be partially or completely interconnected.
In a further embodiment of the process, the first polymer layer having holes and/or the second polymer layer having holes comprises holes of different shapes. In particular, the first and/or second polymer layer having holes can have a plurality of holes of a first shape and a plurality of holes of a second shape and optionally a plurality of holes of a third shape, etc. The holes of different shapes in the first or second polymer layer having holes can be distributed homogeneously or heterogeneously and/or can be partially or completely interconnected. A combination of holes of different shapes on the one hand advantageously enables the total void volume of the resulting voids to be maximised. On the other hand, the electromechanical, in particular piezoelectric, properties of the electromechanical converters produced by the process according to the invention can be adjusted by the choice of hole shape, arrangement and/or distribution.
In particular, at least some of the holes of the first and/or second layer having holes can have shapes that do not have a circular, in particular a substantially circular, cross-sectional area. The reason for this is that the total void volume of layers that comprise solely voids having circular or substantially circular cross-sectional areas is smaller than the total void volume in, for example, a homogeneously distributed arrangement of voids having circular and rhombic cross-sectional areas or in an arrangement based solely on voids having honeycomb cross-sectional areas.
The first and second polymer layers having holes can in principle be formed, independently of one another, from any polymer that is suitable for permitting a polarisation process in the voids and separating the charge layers formed in the polymer films after the charging process. For example, the polymer layers having holes can be formed from an elastomer.
A printing ink, an ink, a paste, a formulation, a lacquer or an adhesive can be used to apply the first and/or second polymer layer having holes or to form the first and/or second polymer layer having holes. These can either be formulated immediately before processing or can be available commercially.
For example, the printing ink, ink, paste, formulation, lacquer or adhesive, or the first and/or second polymer layer having holes, can comprise or be formed from at least one polymer selected from the group consisting of cellulose esters, cellulose ethers, rubber derivatives, polyester resins, unsaturated polyesters, alkyd resins, phenolic resins, amino resins, amido resins, ketone resins, xylene-formaldehyde resins, epoxy resins, phenoxy resins, polyolefins, polyvinyl chloride, polyvinyl esters, polyvinyl alcohols, polyvinyl acetals, polyvinyl ethers, polyacrylates, polymethacrylates, polystyrenes, polycarbonates, polyesters, copolyesters, polyamides, silicone resins, polyurethanes, in particular polyurethanes, and mixtures of these polymers, in particular in the form of binders. If the printing ink, ink, paste, formulation, lacquer or adhesive, or the first and/or second polymer layer having holes, comprises a resin, the printing ink, ink, paste, formulation, lacquer or adhesive, or the first and/or second polymer layer having holes, can optionally further comprise one or more resin hardeners.
A large number of commercially available products can further be suitable, in particular as binders, for the printing ink, ink, paste, formulation, lacquer or adhesive, or the first and/or second polymer layer having holes, which products are marketed, for example, under the trade names Noriphan HTR, Noriphan PCI, Noriphan N2K, Noricryl and NoriPET by Pröll KG, Weiβenburg in Bayern, Germany, or under the trade name Maraflex FX by Marabu GmbH & Co. KG, Tamm, Germany, or under the trade name Polyplast PY by Fujifilm Sericol Deutschland GmbH, Bottrop, Germany, or under the trade names screen printing inks HG, SG, CP, CX, PK, J, TL and YN by Coates Screen Inks GmbH, Nuremberg, Germany, or under the trade names 1500 Series UV Flexiform, 1600 Power Print Series, 1700 Versa Print, 3200 Series, 1800 Power Print plus, 9700 Series, PP Series, 7200 Lacquer and 7900 Series by Nazdar, Shawnee, United States of America.
For a printing ink, ink, paste, formulation, lacquer or adhesive that cures under ultraviolet light there are suitable, in particular as binders, for example epoxy, ester, ether and/or urethane acrylates. Urethane acrylates can be used in the form of solutions in reactive diluents (low viscosity meth/acrylic acid esters), in the form of low viscosity oligomers, in the form of solids for powder coating technology or in the form of urethane acrylate dispersions. Urethane acrylates are obtainable, for example, under the trade name/mark Desmolux from Bayer MaterialScience AG (Leverkusen, Germany). For curing there are suitable, for example, electron-beam curing, mono cure technology and dual cure technology. Isocyanatourethane acryls are particularly suitable for dual cure technology.
The printing ink, ink, paste, formulation, lacquer or adhesive can be water-based or based on solvents other than water.
The printing ink, ink, paste, formulation, lacquer or adhesive, or the first and/or second polymer layer having holes, can comprise or be formed from one or more polyurethanes. In particular, the printing ink, ink, paste, formulation, lacquer or adhesive, or the first and/or second polymer layer having holes, can comprise or be formed from one or more one-component polyurethanes and/or one or more two-component polyurethanes and/or one or more aqueous polyurethane dispersions and/or one or more polyurethane hot-melt adhesives.
For example, the printing ink, ink, paste, formulation, lacquer or adhesive, or the first and/or second polymer layer having holes, can comprise or be formed from one or more one-component polyurethanes comprising prepolymers which can be prepared by reaction of alcohols with a stoichiometric excess of polyfunctional isocyanates having a mean functionality of greater than 2 and up to 4. The prepolymers can optionally further comprise additives and/or solvents.
The prepolymers can be obtained, for example, by reaction of polyisocyanates with alcohols which are mixtures of polyols with on average monofunctional alcohols, to form urethane groups and terminal isocyanate groups.
There can be used as polyols the polyols which are known to the person skilled in the art and are conventional in polyurethane chemistry, such as, for example, polyether, polyacrylate, polycarbonate, polycaprolactone, polyurethane and polyester polyols, as are described, for example, in Ullmanns Enzyklopädie der technischen Chemie, 4th Edition, Volume 19, p. 304-5, Verlag Chemie, Weinheim, or in Polyurethan Lacke, Kleb- and Dichtstoffe by Ulrich Meier-Westhues, Vincentz Network, Hanover, 2007. For example, the polyols called Desmophen® from Bayer MaterialScience AG, Leverkusen, Germany can be used.
As polyfunctional isocyanates having a mean functionality >2 there can be used the products which are conventional in polyurethane chemistry and known to the person skilled in the art, as are described, for example, in Ullmanns Enzyklopädie der technischen Chemie, 4th Edition, Volume 19, p. 303-4, Verlag Chemie, Weinheim. There may be mentioned as examples isocyanates trimerised via biuret groups, such as, for example, trimerised hexamethylene diisocyanate Desmodur® N (trade name of Bayer MaterialScience AG, Leverkusen, Germany), or mixtures thereof with diisocyanates, or isocyanates trimerised via isocyanurate groups, or mixtures thereof with diisocyanates. The adducts of diisocyanates with polyols, for example of toluene diisocyanate with trimethylolpropane, are also suitable.
There can be added to the prepolymers additives such as catalysts for accelerating curing, for example tertiary amines, such as dimorpholinodiethyl ether, bis-[2-N,N-(dimethylamino)ethyl]ether or tin compounds, such as dibutyltin dilaurate or tin(II) octoate, anti-ageing agents and light stabilisers, drying agents, stabilisers, for example benzoyl chloride, adhesion promoters for improving adhesion, plasticisers, for example dioctyl phthalate, as well as pigments and fillers.
Because of the sensitivity of the isocyanates to moisture, it is generally necessary to work with the careful exclusion of water, that is to say anhydrous raw materials are to be used and the admission of moisture during the reaction is to be avoided.
The prepolymers can be prepared by reacting the mixture of polyols and monofunctional alcohol with a stoichiometric excess of di- or poly-functional isocyanate compound. It is also possible, however, to react the monofunctional hydroxyl compound with the isocyanate compound in a preceding reaction.
The printing ink, ink, paste, formulation, lacquer or adhesive, or the first and/or second polymer layer having holes, can, however, also comprise or be formed from one or more two-component polyurethanes, which comprise, for example, a component having isocyanate groups and an isocyanate-reactive component.
There can be used as suitable polyisocyanates for the printing ink, ink, paste, formulation, lacquer or adhesive, or the first and/or second polymer layer having holes, the NCO-functional compounds having a functionality of preferably 2 or more that are known per se to the person skilled in the art. These are typically aliphatic, cycloaliphatic, araliphatic and/or aromatic di- or tri-isocyanates as well as the higher molecular weight secondary products thereof having iminooxadiazinedione, isocyanurate, uretdione, urethane, allophanate, biuret, urea, oxadiazinetrione, oxazolidinone, acylurea and/or carbodiimide structures, which contain two or more free NCO groups.
Examples of such di- or tri-isocyanates are tetramethylene diisocyanate, cyclohexane-1,3- and -1,4-diisocyanate, hexamethylene diisocyanate (HDI), 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethyl-cyclohexane (isophorone diisocyanate, IPDI), methylene-bis-(4-isocyanatocyclohexane), tetramethylxylylene diisocyanate (TMXDI), triisocyanatononane, toluoylene diisocyanate (TDI), diphenylmethane-2,4′- and/or -4,4′- and/or -2,2′-diisocyanate (MDI), triphenylmethane-4,4′-diisocyanate, naphthylene-1,5-diisocyanate, 4-isocyanatomethyl-1,8-octane diisocyanate (nonane triisocyanate, triisocyanatononane, TIN) and/or 1,6,11-undecane triisocyanate as well as arbitrary mixtures thereof and optionally also mixtures of other di-, tri- and/or poly-isocyanates. Such polyisocyanates typically have isocyanate contents of from 0.5 wt. % to 60 wt. %, preferably from 3 wt. % to 30 wt. %, particularly preferably from 5 wt. % to 25 wt. %.
There are preferably used in the printing ink, ink, paste, formulation, lacquer or adhesive, or the first and/or second polymer layer having holes, the higher molecular weight compounds having isocyanurate, urethane, allophanate, biuret, iminooxadiazinetrione, oxadiazinetrione and/or uretdione groups based on aliphatic and/or cycloaliphatic and/or aromatic diisocyanates.
There are particularly preferably used in the printing ink, ink, paste, formulation, lacquer or adhesive, or the first and/or second polymer layer having holes, compounds having biuret, iminooxadiazinedione, isocyanurate and/or uretdione groups based on hexamethylene diisocyanate, isophorone diisocyanate, 4,4′-diisocyanatodicyclohexylmethane, diphenylmethane-4,4′-diisocyanate, diphenylmethane-2,4′-diisocyanate, 2,4-toluoylene diisocyanate, 2,6-toluoylene diisocyanate and/or xylylene diisocyanate.
The preparation and/or use of the isocyanate-containing component can be carried out in a solvent. Examples are N-methylpyrrolidone, N-ethylpyrrolidone, xylene, solvent naphtha, toluene, butyl acetate, methoxypropyl acetate, acetone or methyl ethyl ketone. It is possible to add solvents when the isocyanate groups have reacted completely. It is also possible to use protic solvents, such as alcohols, which serve, for example, to stabilise the solution or to improve the lacquer properties. Arbitrary mixtures of solvents are also possible. The amount of solvent is generally such that 20 wt. % to <100 wt. %, preferably 50 wt. % to 90 wt. %, solutions are obtained.
Catalysts can also be added in order to accelerate the crosslinking. Suitable catalysts are described in “Polyurethane Chemistry and Technology”, Volume XVI, Part 1, Section IV, pages 129-211, The Kinetics and Catalysis of the Isocyanate Reactions. Tertiary amines, tin, zinc or bismuth compounds, or basic salts are suitable, for example. Dibutyltin dilaurate and octoate are preferred.
Suitable isocyanate-reactive components, such as, for example, polyhydroxyl compounds, are known per se to the person skilled in the art. They are preferably the binders known per se based on polyhydroxy polyesters, polyhydroxy polyurethanes, polyhydroxy polyethers, polycarbonate diols or on hydroxyl-group-containing polymers, such as the polyhydroxy polyacrylates, polyacrylate polyurethanes and/or polyurethane polyacrylates known per se. Examples which may be mentioned are the polyols called Desmophen® from Bayer MaterialScience AG, Leverkusen, Germany.
The printing ink, ink, paste, formulation, lacquer or adhesive, or the first and/or second polymer layer having holes, can, however, also comprise or be formed from one or more aqueous polyurethane dispersions, for example a polyurethane-polyurea dispersion. Suitable aqueous polyurethane dispersions for formulating the printing ink, ink, paste, formulation, lacquer or adhesive are those such as are described, for example, in U.S. Pat. No. 2,479,310 A, U.S. Pat. No. 4,092,286 A, DE 2 811 148 A, DE 3603996 and EP 08019884.
Suitable diol and/or polyol components for the preparation of polyurethane-polyurea dispersions are compounds having at least two hydrogen atoms that are reactive towards isocyanates, and a mean molecular weight of from 62 to 18,000 g/mol, preferably from ≧62 to ≦4000 g/mol. Examples of suitable chain-extension components are polyethers, polyesters, polycarbonate, polylactones and polyamides. Preferred polyols contain from ≧2 to ≦4, preferably from ≧2 to ≦3, hydroxyl groups. Mixtures of different compounds of this type are also suitable.
The polyurethane-polyurea dispersion can be used either alone or in combination with one or more hydrophilically modified crosslinkers. The additional crosslinking of the polyurethane-polyurea polymer brings about a marked increase in the heat resistance and hydrolytic stability of the adhesive compound.
It is also possible to use one or more latent-reactive polyurethane-polyurea dispersions. Latent-reactive polyurethane-polyurea dispersions are described, for example, in EP 0 922 720 A and WO 2008/071307. The advantage of this product class is that the crosslinking reaction of the polymer is initiated when the polymer layer having holes is heated during the lamination process, as is necessary in any case.
The dispersion can be used on its own or with binders, auxiliary substances and/or added ingredients known in coating and adhesives technology, in particular emulsifiers and light stabilisers, such as UV absorbers and sterically hindered amines (HALS), antioxidants, fillers, antisettling agents, antifoams, wetting agents, flow improvers, reactive diluents, plasticisers, neutralising agents, catalysts, auxiliary solvents and/or thickeners and/or additives, such as pigments, colourings or mattifying agents. Tackifiers can also be added. The additives can be added immediately before processing. It is also possible, however, to add at least some of the additives before or during the dispersion of the binder.
The choice and metering of these substances, which can be added to the individual components and/or to the mixture as a whole, are known in principle to the person skilled in the art and, without an unduly high outlay, can be determined by means of simple preliminary tests, customised to the specific application in question.
The rheology of the aqueous polyurethane dispersions is preferably adjusted, by means of suitable thickeners, so that they no longer flow after application, for example to the continuous polymer layer. The intrinsic viscosity of the liquid limit in particular can be high. The use of such an aqueous polyurethane dispersion has the advantage that the polymer layer having holes can first be dried after application, whereby the polyurethane polymer—depending on the polymer or polymer mixture used—solidifies and/or crystallises amorphously and the polymer layer having holes can be heated in a subsequent lamination process to just such an extent that the polyurethane polymer softens and/or melts and the continuous polymer layer is wetted, the structure of the polymer layer having holes being retained.
The printing ink, ink, paste, formulation, lacquer or adhesive, or the first and/or second polymer layer having holes, can, however, also comprise or be formed from a reactive or non-reactive polyurethane hot-melt adhesive.
Suitable reactive polyurethane hot-melt adhesives are described, for example, in DE 3827724, DE 4114229 and EP 354527. These hot-melt adhesives have free isocyanate groups which, after application, crosslink with moisture from the substrate and thus achieve the required heat resistance.
The polyurethane hot-melt adhesives can be used on their own or with binders, auxiliary substances and/or added ingredients known in coating and adhesives technology, in particular light stabilisers, such as UV absorbers and sterically hindered amines (HALS), also antioxidants, fillers, wetting agents, flow improvers, reactive diluents, plasticisers, neutralising agents, catalysts, auxiliary solvents, tackifiers and/or additives, such as pigments, colourings or mattifying agents. The additives can be added immediately before processing. It is also possible, however, to add at least some of the additives before or during the preparation of the reactive hot-melt adhesive.
The choice and metering of these substances, which can be added to the individual components and/or to the mixture as a whole, are known in principle to the person skilled in the art and, without an unduly high outlay, can be determined by means of simple preliminary tests, customised to the specific application in question.
Suitable non-reactive polyurethane hot-melt adhesives are described, for example, in DE 1256822, DE 1930336 or EP 192946. Further suitable non-reactive hot-melt adhesives are polyesters and copolyesters, polyamide, polyolefins (APAO), ethylene-vinyl acetate copolymers, polyester elastomers, polyurethane elastomers and copolyamide elastomers.
The printing ink, ink, paste, formulation, lacquer or adhesive, or the first and/or second polymer layer having holes, preferably further comprises at least one additive for improving the electret and/or electromechanical, for example piezoelectric, properties. The additive can improve any polymer properties and parameters that have an effect on the electromechanical, for example piezoelectric, properties of the material. For example, the additive can improve the dielectric constant, the modulus of elasticity, the viscoelastic behaviour, the maximum elongation and/or the dielectric strength of the polymer or polymer mixture. Preference is given to the use of an additive that lowers the dielectric constant and/or the electrical conductivity and/or the modulus of elasticity of the polymer and/or increases the dielectric strength of the polymer. For example, clay particles, fine ceramics powders and/or plasticisers, such as hydrocarbon oils, mineral oils, silicone oils and/or silicone elastomers, in particular having a high molecular weight, can be used as additives. A plurality of properties of the material can advantageously be improved simultaneously by choosing a plurality of additives. The printing ink, ink, paste, formulation, lacquer or adhesive, or the first and/or second polymer layer having holes, can further comprise additives that facilitate application of the polymer layer having holes. These are, for example, flow additives, antifoams and/or rheology additives as well as added ingredients for improving the properties of the polymer layer having holes, such as plasticisers.
The printing ink, ink, paste, formulation, lacquer or adhesive, or the first and/or second polymer layer having holes, can further comprise solvents, in particular before the electromechanical converter is produced. Examples thereof are ethyl acetate, butyl acetate, methoxypropyl acetate, ethoxypropyl acetate, acetone, cyclohexanone, toluene, xylene, Solvesso 100, Shellsol A and/or mixtures of two or more of these solvents.
The first and/or second and/or third continuous polymer layers are preferably compact polymer layers. The term “compact” within the scope of the present invention means that the continuous polymer layers contain as few inclusions, such as gas bubbles, as possible, in particular no such inclusions. In particular, the continuous polymer layers can be polymer films. The first and/or second and/or third continuous polymer layers can in principle be produced independently of one another by any known processes for the production of layers and films, in particular thin layers and films. For example, the first and/or second and/or third continuous polymer layers can be produced, independently of one another, by extrusion, application by doctor blade, in particular solution application by doctor blade, spin coating or spraying. However, it is possible within the scope of the present invention also to use commercially available continuous polymer layers or polymer films as the first and/or second and/or third continuous polymer layer.
Within the scope of the present invention, the first and/or second and/or third continuous polymer layers can in principle be formed, independently of one another, from any polymer or polymer mixture that is suitable for retaining charge over a long period of time, for example several months or years. For example, the first and/or second and/or third continuous polymer layers can comprise or consist of almost any identical or different polymer materials. For example, the first and/or second and/or third continuous polymer layers can comprise or be formed from at least one polymer selected from the group consisting of polycarbonates, perfluorinated or partially fluorinated polymers and copolymers, such as polytetrafluoroethylene (PTFE), fluoroethylenepropylene (FEP), perfluoroalkoxyethylenes (PFA), polyesters, such as polyethylene terephthalate (PET) or polyethylene naphthalate (PEN), polyimides, in particular polyether imide, polyethers, polymethyl methacrylates, cycloolefin polymers, cycloolefin copolymers, polyolefins, such as polypropylene, and mixtures of these polymers. Such polymers are advantageously able to retain the polarisation that is introduced over a long period of time. Suitable polycarbonates are obtainable, for example, by reaction of carbonic acid derivatives, such as diphenyl carbonate, dimethyl carbonate or phosgene, with polyols, preferably diols. Examples of suitable diols are ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, neopentyl glycol, 1,4-bis-hydroxymethylcyclohexane, 2-methyl-1,3-propanediol, 2,2,4-trimethyl-1,3-pentanediol, dipropylene glycol, polypropylene glycols, dibutylene glycol, polybutylene glycols, bisphenol A, bisphenol F, trimethyl-cyclohexyl-bisphenol (bisphenol-TMC), mixtures of these and lactone-modified diols. Polycarbonates prepared from bisphenol A, bisphenol F, trimethyl-cyclohexyl-bisphenol (bisphenol-TMC) and mixtures thereof are preferred, and polycarbonates based on bisphenol A are most particularly preferred. In addition, the continuous polymer layers, independently of one another, can comprise or be formed from a homopolymer.
In addition, the first and/or second and/or third continuous polymer layer can comprise at least one additive for improving the electret and/or electromechanical, for example piezoelectric, properties. The additive can improve any polymer properties and parameters that have an effect on the electromechanical, for example piezoelectric, properties of the material. For example, the additive can improve the electret properties, the dielectric constant, the modulus of elasticity, the viscoelastic behaviour, the maximum elongation and/or the dielectric strength of the polymer or polymer mixture. Preference is given to the use of an additive or a plurality of additives that improve the electret properties, that is to say increase the charge-storing ability, lower the electrical conductivity and/or increase the dielectric strength of the polymer. For example, clay particles, fine ceramics powders and/or plasticisers, such as hydrocarbon oils, mineral oils, silicone oils and/or silicone elastomers, in particular having a high molecular weight, can be used as additives. A plurality of properties of the material can advantageously be improved simultaneously by choosing a plurality of additives.
Within the scope of the present invention, in particular in the electromechanical converter, the first and/or second and/or third continuous polymer layers, independently of one another, can have, for example, a layer thickness of from ≧10 μm to ≦500 μm, for example from ≧20 μm to ≦250 μm.
In addition to the first and/or second and/or third continuous polymer layer, the converter according to the invention can comprise one or more further continuous polymer layers. Such a further continuous polymer layer can be arranged, for example, on the side of the first and/or second and/or third continuous polymer layer that is opposite the adjacent polymer layer having holes.
The continuous polymer layers can optionally be tempered before they are used in the process according to the invention or within the scope of the process according to the invention.
The process can further comprise process step D): applying an electrode to the first continuous polymer layer and an electrode to the covering, in particular to the continuous polymer layer (second or third) of the covering. However, within the scope of the present invention, the electrodes can also be provided together with the first and/or second and/or third continuous polymer layer, in particular can in each case be formed thereon. The electrodes are applied to the outside, that is to say to the side of the first continuous polymer layer or of the covering that is remote from the holes.
The electrodes can be applied by means of processes known to the person skilled in the art. Processes such as, for example, sputtering, vapour deposition, chemical vapour deposition (CVD), printing, application by doctor blade, spin coating are suitable. The electrodes can also be applied in prefabricated form by adhesive bonding.
The electrode materials can be conductive materials known to the person skilled in the art. There are suitable, for example, metals, metal alloys, semiconductors, conductive oligomers or polymers, such as polythiophenes, polyanilines, polypyrroles, conductive oxides or mixed oxides, such as indium tin oxide (ITO), or polymers filled with conductive fillers. Suitable fillers for polymers filled with conductive fillers are, for example, metals, conductive carbon-based materials, for example carbon black, carbon nanotubes (CNTs), or conductive oligomers or polymers. The filler content of the polymers is preferably above the percolation threshold, which is characterised in that the conductive fillers form continuous electrically conductive paths.
Within the scope of the present invention, the electrodes can also be structured. For example, the electrodes can be so structured that the converter exhibits active and passive regions. In particular, the electrodes can be so structured that, in particular in sensor mode, the signals are detected in a space-resolved manner and/or, in particular in actuator mode, the active regions can purposively be triggered. This can be achieved, for example, by providing the active regions with electrodes while the passive regions do not have electrodes.
The process can further comprise process step E): charging the arrangement, in particular sandwich arrangement, obtained in process step C). In particular, the first continuous polymer layer and the covering, in particular the continuous polymer layer (second or third) of the covering, can be charged with charges having different signs. Charging can be carried out, for example, by tribocharging, electron beam bombardment, application of a voltage to the electrodes, or corona discharge. In particular, charging can be carried out by means of a twin-electrode corona arrangement. The needle voltage can be at least ≧20 kV, for example at least ≧25 kV, in particular at least ≧30 kV. The charge time can be at least ≧20 s, for example at least ≧30 s, in particular at least ≧1 minute. Within the scope of the present invention, it is possible either to carry out first process step D) and then process step E) or to carry out first process step E) and then process step D).
The process can further comprise process step F): stacking two or more arrangements, in particular sandwich arrangements, obtained in process step C). The first continuous polymer layer and the covering, in particular the continuous layer (two or three) of the covering, can in each case be in contact with an electrode. Two adjacent continuous polymer layers of different arrangements obtained in process step C) are preferably charged with the same polarisation. In particular, two adjacent continuous polymer layers of different arrangements obtained in process step C) can be in contact with the same electrode, or the same electrode can be in contact therewith.
With regard to further features of a process according to the invention, reference is made explicitly to the explanations given in connection with the electromechanical converter according to the invention and its use.
The present invention further provides an electromechanical, for example piezoelectric, converter, in particular produced by a process according to the invention, which comprises a first continuous polymer layer, a first polymer layer having holes, and a covering, the first polymer layer having holes being arranged between the first continuous polymer layer and the covering, the holes of the first polymer layer having holes being closed on one side by the first continuous polymer layer and on the other side by the covering to form voids.
Because the production process according to the invention is based on a printing and/or coating process, the nature of the surfaces delimiting the holes in particular can be different from that of the surfaces delimiting the holes of holes produced by drilling. For example, the surfaces delimiting holes resulting from the process according to the invention could have fewer burrs and other sharp-edged surface irregularities, which cannot be specified by characteristic values but nevertheless could have an effect, in particular a negative effect, on the electromechanical, in particular piezoelectric, properties.
In an embodiment of the electromechanical converter, the covering comprises a second polymer layer having holes and a second continuous polymer layer, the second continuous polymer layer being arranged on the second polymer layer having holes, and the second polymer layer having holes being arranged on the first polymer layer having holes, in particular to form common voids.
In an embodiment of the electromechanical converter, the covering is a third continuous polymer layer.
In an embodiment of the electromechanical converter, the first polymer layer having holes comprises holes of different shapes, and/or the second polymer layer having holes comprises holes of different shapes.
As already explained, it is advantageously possible by using a combination of holes of different shapes on the one hand to maximise the total void volume of the resulting voids and on the other hand to adjust the electromechanical, in particular piezoelectric, properties.
The holes of the first polymer layer having holes and/or the holes of the second polymer layer having holes can optionally be partially or completely interconnected.
In an embodiment of the electromechanical converter, at least some of the holes of the first polymer layer having holes have shapes that do not have a circular, in particular substantially circular, cross-sectional area, and/or at least some of the holes of the second polymer layer having holes have shapes that do not have a circular, in particular substantially circular, cross-sectional area.
As has also already been explained, the at least partial avoidance of holes having a circular, in particular a substantially circular, cross-sectional area enables the total void volume to be increased.
The first and second polymer layers having holes can in particular be congruent, in particular identical.
The holes in the first and/or second polymer layer having holes can be distributed homogeneously or heterogeneously. In particular, the holes in the first and/or second polymer layer having holes can be distributed homogeneously. Depending on the field of application of the electromechanical converter that is to be produced, however, it can also be advantageous for the holes in the first and/or second polymer layer having holes to be distributed, in particular purposively, heterogeneously in a space-resolved manner.
The holes of the first polymer layer having holes preferably pass right through the first polymer layer having holes, in particular in the direction of the continuous polymer layers; and/or the holes of the second polymer layer having holes pass right through the second polymer layer having holes, in particular in the direction of the continuous polymer layers.
The first and/or second polymer layer having holes can have a plurality of holes of a first shape and a plurality of holes of a second shape and optionally a plurality of holes of a third shape, etc. Holes of different shapes in the first and/or second polymer layer having holes can be distributed homogeneously or heterogeneously and/or can be partially or completely interconnected.
Within the scope of the present invention, some or all of the holes can have, for example, shapes having a cross-sectional area selected from the group consisting of substantially round, for example circular, elliptical or oval, polygonal, for example triangular, rectangular, trapezoidal, rhombic, pentagonal, hexagonal, in particular honeycomb, cross-shaped, star-shaped and partially round and partially polygonal, for example S-shaped, cross-sectional areas. The holes of the first and/or second layer having holes preferably have a honeycomb cross-sectional area or are shaped and/or arranged in a honeycomb; particularly preferably, the holes of the first and second layers having holes have a honeycomb cross-sectional area or are shaped and/or arranged in a honeycomb. A honeycomb shape and arrangement of the holes on the one hand results in a very large total void volume. On the other hand, a honeycomb shape and arrangement of the holes can have high mechanical stability.
The size of the cross-sectional areas can be the same or different in all the holes of the polymer layer having holes.
The first and/or second polymer layers having holes can each have, for example, a layer thickness of from ≧1 μm to ≦800 μm, in particular from ≧10 μm to ≦400 μm. If the electromechanical converter has only one polymer layer having holes, then the first polymer layer having holes can have a layer thickness of from ≧1 μM to ≦800 μm, for example from ≧10 μm to ≦400 μm. If the electromechanical converter has both a first and a second polymer layer having holes, then the overall layer thickness of the first polymer layer having holes and of the second polymer layer having holes can be from ≧1 μm to ≦800 μm, for example from ≧10 μm to ≦400 μm.
The first and/or second and/or third continuous polymer layers, independently of one another, can have a layer thickness of, for example, from ≧10 μm to ≦500 μm, for example from ≧20 μm to ≦250 μm.
The first and/or second polymer layer having holes can, for example, comprise or be formed from at least one polymer selected from the group consisting of cellulose esters, cellulose ethers, rubber derivatives, polyester resins, unsaturated polyesters, alkyd resins, phenolic resins, amino resins, amido resins, ketone resins, xylene-formaldehyde resins, epoxy resins, phenoxy resins, polyolefins, polyvinyl chloride, polyvinyl esters, polyvinyl alcohols, polyvinyl acetals, polyvinyl ethers, polyacrylates, polymethacrylates, polystyrenes, polycarbonates, polyesters, copolyesters, polyamides, silicone resins, polyurethanes, in particular polyurethanes, and mixtures of these polymers. In particular, the first and/or second polymer layer having holes can comprise or be formed from one or more one-component polyurethanes and/or one or more two-component polyurethanes and/or one or more polyurethane hot-melt adhesives.
The first and/or second and/or third continuous polymer layer can, for example, comprise or be formed from at least one polymer selected from the group consisting of polycarbonates, perfluorinated or partially fluorinated polymers and copolymers, such as polytetrafluoroethylene (PTFE), fluoroethylenepropylene (FEP), perfluoroalkoxyethylenes (PFA), polyesters, such as polyethylene terephthalate (PET) or polyethylene naphthalate (PEN), polyimides, in particular polyether imide, polyethers, polymethyl methacrylates, cycloolefin polymers, cycloolefin copolymers, polyolefins, such as polypropylene, and mixtures of these polymers.
Preferably, an electromechanical converter further comprises two electrodes, in particular electrode layers, one electrode being in contact with the first continuous polymer layer and the other electrode being in contact with the covering, in particular the continuous polymer layer (second or third) of the covering. Furthermore, the first continuous polymer layer and the covering, in particular the continuous polymer layer (second or third) of the covering, can have electrical charges with different signs. In particular, an electromechanical converter according to the invention can comprise two or more arrangements, in particular sandwich arrangements, stacked one on top of the other, each of which comprises a first continuous polymer layer, a first polymer layer having holes, and a covering, the first polymer layer having holes being arranged between the first continuous polymer layer and the covering, the holes of the first polymer layer having holes being closed on one side by the first continuous polymer layer and on the other side by the covering to form voids. The first continuous polymer layer and the covering, in particular the continuous layer (two or three) of the covering, can each be in contact with an electrode. Preferably, two adjacent continuous polymer layers of different arrangements have the same charge polarisation. In particular, two adjacent continuous polymer layers of different arrangements are in contact with the same electrode.
With regard to further features of an electromechanical converter according to the invention, reference is made explicitly to the explanations given in connection with the process according to the invention and the use according to the invention.
The present invention further provides the use of a converter according to the invention as a sensor, generator and/or actuator, for example in the electromechanical and/or electroacoustic field, in particular in the field of obtaining energy from mechanical vibrations (energy harvesting), acoustics, ultrasonics, medical diagnostics, acoustic microscopy, mechanical sensor systems, in particular pressure, force and/or strain sensor systems, robotics and/or communication technology, in particular in loudspeakers, vibration converters, light deflectors, membranes, modulators for fibre optics, pyroelectric detectors, capacitors and control systems.
With regard to further features of a use according to the invention, reference is made explicitly to the explanations given in connection with the process according to the invention and the electromechanical converter according to the invention.
Drawings and Test Description
The production according to the invention and the structure of an electromechanical, for example piezoelectric, converter according to the invention are explained in greater detail by means of the drawings, the description of the drawings given hereinbelow and the following test descriptions. It is to be noted that the drawings and the test descriptions are merely descriptive in nature and are not intended to limit the invention in any way.
Drawings
In the drawings:
FIG. 1 a shows, in diagrammatic form, a cross-section through a first polymer layer having holes applied to a first continuous polymer layer;
FIG. 1 b shows, in diagrammatic form, a cross-section through a form of covering comprising a second polymer layer having holes and a second continuous polymer layer;
FIG. 1 c shows, in diagrammatic form, a cross-section through the layer arrangement shown in FIG. 1 a , to which the covering shown in FIG. 1 b has been applied;
FIG. 2 a shows, in diagrammatic form, a cross-section through a first polymer layer having holes applied to a first continuous polymer layer;
FIG. 2 b shows, in diagrammatic form, a cross-section through the layer arrangement shown in FIG. 2 a , to which a covering in the form of a third continuous polymer layer has been applied;
FIG. 3 a shows, in diagrammatic form, a cross-section through the arrangement shown in FIG. 2 b after the charging process;
FIG. 3 b shows, in diagrammatic form, a cross-section through the arrangement shown in FIG. 2 b after the charging process and after the application of electrodes;
FIG. 4 shows, in diagrammatic form, a cross-section through a converter according to the invention having three arrangements stacked one above the other, each arrangement comprising a first continuous polymer layer, a first polymer layer having holes, and a covering in the form of a third continuous polymer layer; and
FIG. 5 a - 5 i show top views of different embodiments of polymer layers having holes.
FIG. 1 a shows, in diagrammatic form, a cross-section through a first continuous polymer layer 1 a , to which a first polymer layer 2 a having holes 3 a has been applied.
FIG. 1 b shows, in diagrammatic form, a cross-section through a form of covering comprising a second polymer layer 2 b having holes 3 b and a second continuous polymer layer 1 b.
FIG. 1 c shows, in diagrammatic form, a cross-section through the layer arrangement shown in FIG. 1 a , to which the covering shown in FIG. 1 b has been applied. FIG. 1 c shows that the holes 3 a of the first polymer layer 2 a having holes 3 a and the holes 3 b of the second polymer layer 2 b having holes 3 b are so formed and arranged that, after application of the covering 1 b , 2 b to the first polymer layer 2 a having holes 3 a , a hole 3 a of the first polymer layer 2 a having holes 3 a and a hole 3 b of the second polymer layer 2 b having holes 3 b overlap completely to form a common void 5 .
FIG. 2 a shows, in diagrammatic form, a cross-section through a first continuous polymer layer 1 , to which a first polymer layer 2 having holes 3 has been applied. FIG. 2 a shows that the holes 3 of the first polymer layer having holes pass right through the polymer layer 2 having holes 3 .
FIG. 2 b shows that a covering in the form of a third continuous polymer layer 4 has been applied to the first polymer layer 2 having holes 3 of the layer arrangement shown in FIG. 1 a . FIG. 2 b shows that the holes 3 of the first polymer layer 2 having holes 3 have been closed on one side by the first continuous polymer layer 1 and on the other side by the third continuous polymer layer 4 to form voids.
FIG. 3 a shows, in diagrammatic form, a cross-section through the arrangement shown in FIG. 2 b and shows the charge distribution after charging of the arrangement shown in FIG. 2 b . FIG. 3 a shows that the negative charges are located on the first continuous polymer layer 1 and the positive charges on the third continuous polymer layer 4 .
FIG. 3 b shows, in diagrammatic form, a cross-section through the arrangement shown in FIG. 2 b after the charging process and after the application of electrodes. The first 1 and third 4 continuous polymer layers are each in contact with an electrode 6 a , 6 b . The electrodes 6 a , 6 b are in the form of electrode layers on the sides of the first 1 and third 4 polymer layers that are opposite the sides adjoining the polymer layer 2 having holes and forming the voids 5 .
FIG. 4 shows, in diagrammatic form, a cross-section through a converter according to the invention having three arrangements stacked one on top of the other, each arrangement comprising a first continuous polymer layer 11 a , 11 b , 11 c , a first polymer layer 12 a , 12 b , 12 c having holes, and a covering in the form of a third continuous polymer layer 14 a , 14 b , 14 c . FIG. 4 shows that two adjacent continuous polymer films 11 a , 14 b ; 11 b , 14 c of different arrangements are charged with the same polarisation and are in contact with the same electrode 16 ab ; 16 bc . FIG. 4 additionally shows the possibility of connecting the electrodes 16 a , 16 ab , 16 bc , 16 c to a voltage/current measuring/supply/storage device 17 .
FIGS. 5 a to 5 i show different embodiments of polymer layers having holes 3 and hole forms. However, the embodiments and forms shown in FIGS. 5 a to 5 i are only examples and are not intended to limit the invention in any way. For reasons of clarity, only one hole of a particular shape is identified by a reference numeral by way of example in FIGS. 5 a to 5 i.
FIG. 5 a shows a polymer layer having holes 3 , the holes of which have a circular cross-sectional area. FIG. 5 a additionally shows that a plurality of small holes 3 can be formed by the process according to the invention.
FIG. 5 b shows a polymer layer having holes 3 , the holes 3 of which have an elongate, rectangular cross-sectional area. FIG. 5 b likewise shows that a plurality of small holes 3 can be formed by the process according to the invention.
FIG. 5 c shows a polymer layer having holes 3 , the holes 3 of which have a cross-shaped cross-sectional area.
FIG. 5 d shows a polymer layer having holes 3 , the holes 3 of which have a circular cross-sectional area. FIG. 5 d shows that it is not possible to achieve an optimum total void volume using only holes 3 having circular cross-sectional areas.
FIG. 5 e shows a polymer layer having holes 3 , 3 ′, of which some of the holes have a circular cross-sectional area 3 and some have a rhombic cross-sectional area 3 ′. FIG. 5 e shows that, with a homogeneously distributed arrangement of holes having circular 3 and a rhombic 3 ′ cross-sectional areas, a larger total void volume can be achieved than in the case of the use of only holes 3 having circular cross-sectional areas as shown in FIG. 5 d.
FIG. 5 f shows a polymer layer having holes 3 , the holes 3 of which have a honeycomb cross-sectional area. FIG. 5 f shows that, by using an arrangement based solely on holes 3 having honeycomb cross-sectional areas, it is possible to achieve a markedly larger total void volume than in the case of the use of only holes 3 having circular cross-sectional areas as shown in FIG. 5 d.
FIG. 5 g shows a polymer layer having holes 3 , the holes 3 of which have a honeycomb cross-sectional area and are partially interconnected.
FIG. 5 h shows a polymer layer having holes 3 , 3 ′, 3 ″, the holes of which are of different shapes and sizes and have cross-shaped 3 ′, 3 ″ and substantially honeycomb 3 cross-sectional areas. FIG. 5 h further shows that the holes are distributed inhomogeneously and are partially interconnected.
FIG. 5 i shows a polymer layer having holes 3 , the holes 3 of which have been formed by applying a combination of different structures, in particular of hexagons/honeycombs, crosses and points of different point and line thicknesses, to a continuous polymer layer 1 by a printing and/or coating process. FIG. 5 i further shows that at least the edge regions of the continuous polymer layer can be printed and/or coated with a closed structure in order to obtain, on completion of the production process according to the invention, one or more closed voids in contact with the continuous polymer layers. In this manner, a continuous void can be formed. FIG. 5 i further shows that, within the scope of the present invention, a polymer layer having holes can also be understood as being a polymer layer which has only one hole 3 , in particular which can also be understood as being the combination or connection of a plurality of holes.
EXAMPLES
Test Description
Example 1
In order to produce a polymer layer having holes by a screen printing process, a first screen printing paste was formulated. This contained 47.14 wt. % Desmodur® N75 MPA and 52.11 wt. % Desmophen® 670. In order to reduce the flow of the paste and bubble formation during printing, 0.75 wt. % flow improver (BYK 410 50% in butoxyl) was added to the formulation.
Example 2
In order to produce a further polymer layer having holes by a screen printing process, a second screen printing paste was formulated. In this paste, 40.40 wt. % Desmodur® N75 MPA, 44.59 wt. % Desmophen® 670, 11.26 wt. % ethoxypropyl acetate, 3.30 wt. % flow improver and 0.45 wt. % of a 1:1 mixture of BYK 410 with butoxyl were used.
A number of screen printing experiments showed that it is possible using the screen printing pastes according to Examples 1 and 2 to apply both a single printed layer and a plurality of printed layers in succession. In particular, a printed layer can be applied to a previous printed layer that has not yet hardened completely (wet-on-wet process). It has been found that a plurality of printing steps can be carried out, with intermediate drying, in order to increase the layer thickness. For example, a printed layer can be applied twice, with intermediate drying, to a continuous polycarbonate film by the wet-on-wet process. Fabrics having from 12 to 200 threads per centimeter, preferably having from 22 to 120 threads per centimeter, were used for printing. In order to achieve a good layer thickness in the case of fine structures, a fabric having 90 threads per centimeter was used. In this manner it was possible to achieve layer thicknesses of from 7 μm to 12 μm by wet-on-wet printing and layer thicknesses of from 15 μm to 25 μm by wet-on-wet printing twice with intermediate drying.
The foregoing examples of the present invention are offered for the purpose of illustration and not limitation. It will be apparent to those skilled in the art that the embodiments described herein may be modified or revised in various ways without departing from the spirit and scope of the invention. The scope of the invention is to be measured by the appended claims. | The present invention relates to a method for producing an electromechanical, for example piezoelectric, transducer in which a first polymer layer comprising cutouts is applied to a first continuous polymer layer by means of a printing and/or coating method, a cover is applied to the first polymer layer comprising cutouts in such a way that the cutouts of the first polymer layer comprising cutouts are closed off with the formation of cavities, and the cover is connected to the first polymer layer comprising cutouts. The invention also relates to electromechanical transducers produced by the method according to the invention, and the use of said electromechanical transducers. | 8 |
BACKGROUND OF THE INVENTION
The invention concerns an opener for opening flaky fiber material, which opener is incorporated via a short feed pipe that can be admitted with a transporting air flow under suction pressure and charged with fiber flakes, as well as via a discharge pipe, into a pneumatic conveyor line for the processing of fiber material, said opener having a driven opening disk with spikes, to which is assigned a fixed counter opening disk, provided with radially outward extending rows of spikes in the direction of the opening disk spikes.
Various designs of such openers are known. Thus, the DE 33 33 750 A1, for example, discloses an opener for opening and cleaning of fiber material, which comprises two opposite arranged rollers, positioned parallel above grate rods, grids or the like and below a closed covering cap in a horizontal plane and provided with spikes or the like, wherein the intake and discharge openings are arranged such that the fiber material is fed in and discharged in a direction parallel to the rollers and by means of an air flow. Such openers operating with spiked rollers require a large amount of floor space, have a low degree of opening with a poor flow rate, and are subject to high wear and tear. In addition, there is the danger of lap formation on the rollers with subsequent blocking.
The GB-A-996 604 furthermore discloses a fiber opening and cleaning machine with a driven opening disk that is installed in a housing and a stationary counter opening disk, located on the opposite side, with a space in-between. A fan wheel sits on the drive shaft for the opening disk and is located opposite the central opening in the counter opening disk. The opening in the counter opening disk is connected to a material feed line via a cone-shaped section of pipe, which discharges from the top into the housing. The opening disk and the counter opening disk are surrounded peripherally by fixed grate rods, through which dust travels on the one hand in horizontal direction to a ring-shaped chamber located inside the housing, while opened fiber material travels on the other hand in vertical direction to a venting hood that is located on the top of the housing and is connected to a suction line.
The GB-A-478 760 furthermore discloses a Crighton opener with a housing erected on a floor level and having a reverse U-shaped design, which opener comprises on the inside, in the lower region of said housing, a shaft that is supported on the floor and has a a short feed pipe attached to its side. On its top, the shaft supports a cage that is enlarged away from it in a truncated-cone shape and consists of individual grate rods. Located above this cage is a driven opening device, designed as cross wheel and functioning as a beater, which is connected to a discharge/feed-in pipe and is designed to drive foreign matter downward, in the is direction of the floor. Exhaust nozzles, which allow the continuous suctioning out of lighter foreign matter, are assigned to the cage side, inside a chamber between cage and housing.
In addition, the EP 0 572 495 B1 discloses an opener of this type, comprising a housing with built-in opening disk, which is incorporated via a short feed pipe and a short discharge pipe into a pneumatic conveying line for the processing of fiber material. The short feed pipe that discharges into the bottom part of the housing turns into an open hollow cylinder extending into the cylindrical housing, which is connected to the short discharge pipe by forming a ring-shaped chamber. At a specific, parallel distance to the free front of the hollow cylinder, a driven opening disk is arranged, which covers this cylinder and which is provided with sharp spikes pointing in the direction of the hollow cylinder. A fixed, circular-segment shaped counter opening disk is inserted into the front of the hollow cylinder, which is provided with sharp spikes pointing in the direction of the opening disk. These counter opening disk spikes can be installed such that they are tilted in rotational direction of the opening disk. To be sure, this represents a considerable improvement in the degree of opening for the flaky fiber material, but the inflexible opener of the spikes on the rotating opening disk as well as on the fixed counter opening disk nevertheless involves the danger of fiber flakes getting caught in the spikes and a lap formation on the spikes, which in extreme cases will clog the rows of spikes and will impede or even prevent the opening of the succeeding flaky fiber material. In that case, the machine must be stopped and the rows of spikes must be freed of fiber material wound around them.
DISCLOSURE OF THE INVENTION
It is therefore the object of the present invention to create an opener of the aforementioned type, which further improves the effectiveness of the known machines and which prevents in all cases the occurrence of fibers being caught in the opening region.
This object is solved in accordance with the invention in that the angle of at least one row of spikes on the counter opening disk can be adjusted continuously via a drive such that they tilt back and forth in rotational direction or counter to the rotational direction of the opening disk.
The essential advantages obtained with the opener according to the invention consist of an excellent degree of opening and a high capacity. The fiber air flow entering the short feed pipe passes through the hollow cylinder and exits from its open front where it is intercepted by the opening disk, operating at a relatively high speed, wherein the flaky fiber material is opened by the spikes on the opening disk and, as a result of the centrifugal force and together with the air, is guided through the peripheral discharge slot between opening disk and hollow cylinder and into the ring-shaped chamber. From there, the fiber air flow is then suctioned off via the short discharge pipe. The circular-segment shaped counter opening disk according to the invention, so-to-speak causes a combing of the flaky fiber material, without making it possible for the fibers to adhere to the spikes. These are constantly stripped off as a result of the permanent change in the angle of the spikes tilting back and forth, so that a lap formation of the fiber material on the opening disk is reliably prevented. As a result of this, such fiber-opening machines reach a high degree of efficiency not reached so far and have a correspondingly higher capacity.
In order to increase the efficiency of the rotating opening disk, one advantageous embodiment of the invention provides that the counter opening disk has a circular-segment shape, and that the first row of the spikes is arranged in rotational direction of the opening disk, behind the circular-segment shaped cutout in the counter opening disk, wherein the row of spikes extends crosswise to the rotational direction of the opening disk.
In a further embodiment according to the invention, several of the rows of spikes extend radially outward from the center point in the counter opening disk and form a ballistic curve, where the number of spikes in the rows decreases in rotational direction of the opening disk. This results in a saving of components, since the capacity required to open the flaky fiber material decreases in rotational direction of the opening disk, owing to the centrifugal force created by the fiber air flow, but is higher at the outer circumference of the counter opening disk than in the center region of the counter opening disk.
The degree of effectiveness of the process of opening the flaky fiber material can be increased further in that two parallel, side-by-side extending rows of spikes are arranged on the counter opening disk, for which the angle can be adjusted continuously to move back and forth in counter direction to each other or in the same direction. As a result of this, the opening effect on the fiber material is nearly doubled, so-to-speak, since this material passes the rows of spikes twice, which rows can tilt back and forth. The spikes moving back and forth are mounted on a rotatable shaft to achieve the angle adjustment.
In addition, it can be provided that respectively at least one row of fixed spikes is arranged between neighboring, parallel and side-by-side extending rows of spikes, for which the angle can be adjusted continuously back and forth. This may be advisable if sufficient space exists between the two rows of spikes that are tilting back and forth to have a row of rigidly secured spikes on the counter opening disk. If necessary, the spikes in the rigidly secured row of spikes on the counter opening disk can be installed such that they are tilted in rotational direction of the opening disk in order to support the effect of opening the flaky fiber material.
The circular-segment shaped cutout in the counter opening disk is defined by a circumferential angle α of approximately 120° to achieve an optimum suction effect in the transport flow of the fiber material.
In order to improve the opening effect, one advantageous embodiment of the subject according to the invention provides that the counter opening disk has spikes only over an angular region β of approximately 120°. As previously explained, it makes sense if the pointy spikes in that case are arranged in a ballistic curve on the counter opening disk.
For an easier installation of the rows of spikes, at least the rows of spikes that can be moved back and forth to change the angle are mounted in an insert, which can be fitted into a corresponding recess in the counter opening disk. With this embodiment, it is possible to provide the insert with a lip seal in the direction of the opening disk, which seals the shaft studded with the spikes to prevent the fiber material from exiting between the opening disk and the counter opening disk. This prevents fine fibers from clogging the shafts studded with spikes. It makes sense to design the spikes extending into the fiber material discharge such that they are pointed.
In a special embodiment of the invention, the rows of spikes that can be adjusted back and forth to change the angle are advantageously actuated by a motor-operated crank mechanism. For this, the crank mechanism is provided with an eccentric cam, which transmits the drive movement to the respective connecting rod for the crank mechanism. The motor for the crank mechanism can in this case be an electric motor, a pneumatic motor or a hydraulic motor.
An alternative solution for the problem underlying the invention distinguishes itself in that at least one row of the spikes on the counter opening disk is positioned such that the angle can be adjusted in rotational direction and counter to the rotational direction of the opening disk, wherein a spring acts upon the spikes in the rotational direction of the opening disk. The spikes clean themselves as a result of this measure. If too much fiber material is wrapped around the spikes, the spikes move in the direction counter to the spring action and occupy a position counter to the rotational direction of the opening disk, as a result of which the spikes are freed of the fiber material. It makes sense if a tension spring or a compression spring is assigned to each row of spikes for which the angle can be adjusted. It is preferable if the tension spring or the compression spring is a steel spring or a rubber spring.
Another alternative solution to the invention is that at least one spike on the counter opening disk is held spring-mounted and tilted in rotational direction of the opening disk. As a result of this measure, the spike wrapped with too much fiber material will tilt counter to its spring-admission, thereby freeing the spike of the fibrous material wrapped around it when the opener is operated. Thus, a virtual self-cleaning of the spike occurs. It is preferable if each spike of at least one row of spikes on the counter opening disk is formed by the free front end of a spiral spring, wherein the angle of each spike can be adjusted in rotational direction and counter to the rotational direction of the opening disk and is held spring-loaded in the rotational direction of the opening disk.
BRIEF DESCRIPTION OF THE DRAWINGS
The idea upon which the invention is based is explained in further detail in the following description and with the aid of embodiments shown in the drawings. Shown are in:
FIG. 1 A longitudinal section through an opener according to the invention;
FIG. 2 An enlarged view of the detail "X" according to FIG. 1;
FIG. 3 A view from above of the counter opening disk of the opener, along the line I--I in FIG. 1;
FIG. 4 An enlarged sectional view of the detail "Y" according to FIG. 2;
FIG. 5 A view in the direction of arrow "Z" in FIG. 4;
FIG. 6 A partial sectional view along the line II--II according to FIG. 3;
FIG. 7 A view from above of the counter opening disk according to FIG. 3, prior to assembly;
FIG. 8 A sectional view along the line III--III according to FIG. 7;
FIG. 9 A partial view from the side of the counter opening disk of an alternative opener according to the invention;
FIG. 10 A partial sectional view along the line II--II in FIG. 3, for an illustration according to FIG. 9;
FIG. 11 An alternative embodiment of the illustration according to FIG. 9;
FIG. 12 A partial sectional view along the line II--II in FIG. 3, for an illustration according to FIG. 11; and
FIG. 13 A partial view from the side of the counter opening disk of an additional alternative opener according to the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The opener 1 comprises a cylindrical housing 2 with a lower region that is designed to extend conically tapered toward the base 3 of housing 2. A ring flange 4 with a short feed pipe 5 that extends into the housing 2 such that it can be moved through sliding is located in the center of the outside of base 3 for housing 2. The short feed pipe 5 is held in its changeable position within the ring flange 4 by a connected cogwheel mechanism 6. A transport air flow under suction pressure, which is charged with fibrous flakes, flows from a machine supplying fibrous flakes is in the direction of arrow A through the short feed pipe 5 and into the opener 1.
Inside housing 2, the short feed pipe 5 is connected to a hollow cylinder 7, wherein the lower region of the hollow cylinder 7 is designed to expand in a truncated-cone shape outward from the short feed pipe 5. The parallel extending walls of the hollow cylinder 7 and the housing 2 form an annular chamber 8 between them, from which a short discharge pipe 9 extends outward in the lower region. A short fresh-air feed pipe, which is not shown and is located opposite the short discharge pipe 9, furthermore discharges into the lower region of the ring chamber 8. This allows fresh air to flow into the ring chamber 8, which avoids fiber deposits. Connected to the short discharge pipe 9 is a suction feed line, not shown here, for a ventilator that suctions off the fiber air flow in the direction of arrow B.
A circular ring flange 10 is provided on the upper outside end of housing 2, which is connected via screws 11 that are distributed evenly over the circumference to a circular cover disk 12. The opening 15 of the circular cover disk 12 is closed off by a lid 13 resting on it. The position of lid 13 is secured with screw connections 14 that are distributed evenly over the circumference. A drive shaft 15 for an opening disk 16 inside the housing 2 extends through the center of the lid 13.
The drive shaft 15 is supported on a bearing 17, held inside a bearing block 18 with associated bearing cover 19, which is attached to the outside of lid 13. A drive wheel 20 is attached so as to rotate along to the end of drive shaft 15, which projects over the bearing cover 19 of bearing block 19 [sic], which drive wheel can be linked with gears to a drive motor. A holding flange 21 for opening disk 16 is attached so as to rotate along to the end of drive shaft 15, which extends into the housing 2. The holding flange 21 that is fixedly attached to the drive shaft 15 is connected with screw connections 22 to the opening disk 16.
The opening disk 16 has a slightly larger diameter than the diameter of the hollow cylinder 7 and is fitted with pointed spikes 23 on the side facing the hollow cylinder 7, which spikes extend at an angle toward the outside. A ring flange 24 that is attached to the inside of lid 13 concentrically surrounds the opening disk 16.
The free front end of hollow cylinder 7, which is arranged coaxially to the opening disk 16, ends at a certain parallel distance to the opening disk 16, wherein this distance can be varied with the aid of the cogwheel mechanism 6, in dependence on the type of fiber air flow, to achieve an optimum degree of opening for the fiber material. Located opposite the opening disk 16 is a circular segment-shaped counter opening disk 25, which is fitted into the front of hollow cylinder 7 and which is provided according to FIG. 7 with pointed spikes 26, at least over an angular region β of approximately 120°. The counter opening disk 25 furthermore has a circular segment-shaped cutout 27, which is defined by a circumferential angle α of approximately 120°. The counter opening disk 25 thus closes off more than half of the front of hollow cylinder 7. The resulting, reduced discharge opening 28 of hollow cylinder 7 guides the fiber air flow in a compressed form to the opening disk 16, which opens the fiber material in a joint action with the counter opening disk 25. The counter opening disk 25 is rigidly secured to the wall of hollow cylinder 7 by means of a flange 29.
The circular segment-shaped counter opening disk 25 according to FIG. 3 is provided with two shafts 30 and 31, extending parallel to each other and parallel to the diameter of counter opening disk 25, which shafts are fitted with the pointed spikes 26. These shafts 30 and 31 are respectively positioned in bearings 32, which themselves are secured in inserts 33, as follows in particular from FIG. 6. These inserts 33 are fitted into cutouts 34 in the counter opening disk 25. Owing to the bearings 32, the shafts 30 and 31, which support the spikes 26, are mounted on the counter opening disk 25 such that they can tilt. Between the shafts 30 and 31 that support the rows of spikes 26, a parallel-extending row of spikes 26 is arranged, wherein these spikes 26 are fixedly inserted in the counter opening disk 25.
In accordance with FIG. 7, the counter opening disk 25, provided with fastening holes 35 distributed over its outer circumference, has further rows of spikes 26, which extend essentially radial to the outside circumference of the counter opening disk 25. The fastening holes 36 for the respective insert 33 for shafts 30 and 31 are visible in this figure as well. The circular segment-shaped cutout 27 in the counter opening disk 25 furthermore has a guide surface 37 for diverting the fiber material to the rows of spikes 26. The movement direction of the flaky fiber material is in rotational direction of the opening disk 16 and is shown with the arrow C.
In the embodiments according to FIGS. 1 to 8, the shafts 30 and 31, which are fitted with rows of spikes 26, are placed into a rotating motion by a crank mechanism 39 that is operated by a drive motor 38. The crank mechanism 39, described in detail in the following, is shown in FIG. 4.
The drive motor 38 is mounted in a suitable way with an angle flange 40 on the hollow cylinder 7. The motor shaft 41 is connected to an eccentric cam 43 by means of a slot and feather connection 42. The eccentric cam 43 is secured such that it can rotate in a bearing 44 and is surrounded by a cover flange 45. Projecting from the eccentric cam 43 is an eccentric pin 46, on which two drive rods 49 and 50 are mounted by way of respective bearing eyes 47, which are attached with a clamping screw 48 to the eccentric pin 46. In accordance with FIG. 3, the drive rod 49 is used to move the rear shaft 31 that is provided with spikes, and the drive rod 50 is used to move the front shaft 30 that is provided with spikes in the counter opening disk 25. The drive shafts 49 and 50 are respectively connected with their upper ends to the shaft journals 51 and 52 of the shafts 30 and 31, meaning they have joint bars 53 in-between, which are secured with the aid of additional clamping screws 48. The length of piston rods 49 and 50 can be adjusted to the respective conditions with an adjustable screw coupling 54.
The double arrows D in FIG. 5 indicate the movement direction of the rows of spikes 26, for which the angle can be adjusted back and forth continuously with the aid of crank mechanism 39. The rows of spikes 26 move in counter direction toward each other or away from each other. As a result of this pendulum movement, the flaky fiber material cannot get snagged and cannot form laps on the spikes 26 since these laps are stripped off by the following fiber goods and the surrounding air flow, owing to the varied positions of the spikes 26 during the angle adjustment. This movement in counter direction of the two rows of spikes 26 is clearly visible in FIG. 6. Said figure also shows a lip seal 55, installed at the insert 33, which seals the respectively associated shaft 30 or 31 for the rows of spikes 26 against the space between the opening disk 16 and the counter opening disk 25.
In the embodiment of opener 1 that is shown in FIGS. 9 and 10, the shafts 30 and 31, fitted with spikes 26, are respectively acted upon by a spring 56, that is in such a way that the spikes 26 are positioned at an angle in rotational direction of the opening disk 16. A tension spring 57 is provided for shaft 30, which is arranged fixedly on a frame and at a point G, while for the shaft 31 a compression spring 58 is provided at a fixed point G on a frame. The springs 57 and 58 are pushed counter to their spring force by the fibers of the flaky fiber material flowing in the direction of arrow C onto the spikes 26, wherein the spikes 26 of the respective shaft 30 or 31 are moved as well. If the spikes 26 of the respective shaft 30 or 31 pass their vertex, the fibers attached to them are stripped off and the starting position, owing starting position, owing to the respective force of their associated springs 57 or 58. In accordance with FIG. 9, this results in a reciprocating movement in the direction of arrows D.
FIGS. 11 and 12 illustrate an alternative embodiment of the representation according to the FIGS. 9 and 10, in which the springs 57, 58 are replaced by elastic strips 59 and 60, which are attached fixedly to a frame at respective points G. The resulting effect is the same as for the embodiment described in the above.
In the embodiment of opener 1 as shown in FIG. 13, the adjustment of the angle for spikes 26 is realized with spiral springs 61, which are arranged below the counter opening disk 25. Each of these spiral springs 61 is designed as a spike 26 on its free, front end, which can be moved back and forth inside a V-shaped opening 62 in the counter opening disk 25. The starting position for these spikes 26 is again at an angle, in rotational direction of the opening disk 16. The operational principle in this case is the same as that for the previously described shafts 30, 31 with spikes 26, which are admitted by a spring force. | An opener for opening flaky fiber material comprising a driven opening disk having a first side and a second side and which rotates in a direction; a first plurality of spikes is mounted on the first side of the opening disk; a counter opening disk which has a circumference, a first side facing the opening disc and a second side, fixedly mounted parallel and opposite to the first side of the opening disk; a second plurality of spikes is mounted on the first side of the counter opening disk and is fitted so as to tilt at an angle in a direction of the opening disk and is arranged substantially radially in rows, and a drive mechanism for moving the angle of at least one row of the spikes on the counter opening disk back and forth in the rotational direction and counter to the rotational direction of the opening disk. | 3 |
STATEMENT OF RIGHTS
The U.S. Government has a paid-up license in this invention and the right in limited circumstances to require the patent owner to license others on reasonable terms as provided for by the terms of Grant No. EY 05681 awarded by National Institute of Health.
BACKGROUND OF THE INVENTION
(1) Field of the Invention
The invention relates to the formation of immortalized cell lines and more particularly to immortalized epithelial cell lines infected with a hybrid SV40 adenovirus, as well as to methods of preparing the cell lines and uses therefore.
(2) Description of the Related Art
The establishment of lens epithelial cells in tissue culture is of considerable importance not only for the study of the problem of cell differentiation, but also is valuable for studying the etiology of primary and secondary cataract. It is also of interest as a progenitor of lens fibers in vivo and because information concerning the regulation of their growth and gene expression is limited. Although there have been a number of studies concerning cell lines of animal lens epithelial cells in culture, attempts to grow human lens epithelia have only been modestly successful.
It is well known that lens epithelial cells undergo a developmental transition into fiber cells of the lens cortex, a process characterized by distinct biochemical changes such as the synthesis of fiber-specific protein, β and γ-crystallins and morphological changes such as cell elongation, loss of cellular organelles and disintegration of the nucleus. The lens epithelium is located on the anterior surface of the lens immediately beneath the capsule and is thought to play a pivotal role in the development and progression of human cataracts, particularly those caused by exogenous mutagens. Data from experimentally induced cataracts and clinical experience suggest that primary damage to the genome of the epithelial cells, mediated by abnormal differentiation to lens fiber cells is collectively expressed as a cataract. See Worgul B. V., Merriam G. R. and Medvedovsky C. "Cortical cataract development--an expression of primary damage to the lens epithelium." Lens Eve Tox Res. 1989;6:559-571.
Early attempts to culture human lens epithelial cells were not very successful, due to their low proliferative ability in vitro, which decreased with age of the tissue. See, for example, Tassin J., Malaise E. and Courtois Y. "Human lens cells have an in vitro proliferative capacity inversely proportional to the donor age." Exp Cell Res. 1979; 123:388-392; Hamada Y. and Okada TS. "In vitro differentiation of cells of the lens epithelium of human fetus." Exp Eye Res. 1978; 26:91-97; Reddan J. R., McGee S. J., Goldenberg E. M., and Dziedzic. "Both human and newborn rabbit lens epithelial cells exhibit similar and limited growth properties in tissue culture." Curr Eye Res. 1982/1983; 2:399-405; and Jacob T. J. C., "Human lens epithelial cells in culture." Exp Eye Res. 1987; 45:93-104.
More recently, human lens epithelial cells have been cultured using fetal or infant lens epithelial explants. These efforts demonstrated the presence of crystallins but revealed their decreased production after several cell passages. See, Reddy V. N., Arita L. T., Zigler J. S., Jr. and Huang Q. L., "Crystallins and their synthesis in human lens epithelial cells in tissue culture." Exp Eye Res. 1988; 47:465-478; and Arita T., Lin L-R and Reddy V. N., "Differentiation of human lens epithelial cells in tissue culture." Exp Eye Res. 1988; 47:905-910.
Primary cultures of infant and fetal cells have been successfully grown and cultured through at least three (3) passages with the consistent formation of a monolayer with population doublings of up to 12 in culture. See Nagineni C. N., and Bhat S. P., "Human fetal epithelial cells in culture: an in vitro model for the study of crystallin expression and lens differentiation." Curr Eye Res. 1989; 8:285-291. These cells have been shown to express α, β and γ-crystallins characteristic of epithelial cells undergoing differentiation into fibers, synthesize the capsule in vitro, and can undergo cell differentiation into fiber like cells of lentoids on low protein-binding surfaces or in co-cultures of lens epithelial cells and ciliary fibroblasts. Despite these advances, the practical utility of human lens epithelial cells is hindered by the limited availability of infant and fetal lenses, diminished in vitro growth after 4-6 population doubling levels (pdls) in cell culture, the lack of continuous cell lines, and the long proliferation times required to obtain a sufficient number of cells for use as a model for studying cell differentiation and the etiology of cataract.
Further studies have been undertaken with virus-transfection of mammalian cells with transforming virus to immortalize cells in vitro. Zeitlin PL., Lu L., Rhim J., Cutting G., Stetten G., Kieffer K. A., Craig R. and Guggino W. B., "A cystic fibrosis bronchial epithelial cell line: immortalization by Adeno-12-SV40 infection." Am. J. Respir. Cell Mol. Biol. 1991. 4:313-319; Hoffman M-C, Narisawa S., Hess R. A. and Millan J. L., "Immortalization of germ cells and somatic testicular cells using the SV40 large T antigen." Exp Cell Res. 1992, 201:417-435; and Bartek J., Bartkova J., Kyprianou N., Lalani E-N., Staskova Z., Shearer M., Chang S. and Taylor-Papadimitrou J., "Efficient immortalization of luminal epithelial cells from mammary gland by introduction of similar virus 40 large tumor antigen with a recombinant retrovirus." Proc. Natl. Acad. Sci. USA 1991; 88:3520-3524. Limited success has been reported with bovine and rat lens epithelium. Miller G. G., Blair D. G., Hunter E., Mousa G. Y. and Trevithick J. R., "Differentiation of rat lens epithelial cells in tissue culture (III). Functions in vitro of a transformed rat lens epithelial cells line". Develop Growth an Differ. 1979;21:19-27. Bovine lens epithelial cells have also been conditionally immortalized by a temperature-sensitive mutant; of the SV40 virus and rat lens epithelial cells have been transformed using rous sarcoma virus, retaining partially differentiating function as shown by β-crystallin synthesis. No immortalized cell lines exist, however, for the human lens epithelium. However, the availability of such a cell line would greatly enhance the study of human lens epithelial physiology, and may aid in the design of drugs that inhibit both primary and secondary human cataracts. Thus, the availability of a cell line which maintains the normal differentiating functions of the lens epithelial cells would be of practical importance in the study of cataractogenesis and agents that inhibit cataract.
SUMMARY OF THE INVENTION
The present invention relates to the formation of immortalized cell lines and more particularly to immortalized human lens epithelial cells using a hybrid adenovirus (Ad12-SV40) to maintain propagation of the cells in vitro. The immortalized human lens epithelial cells can be maintained in culture for at least 23 passages and over 55 population doublings, with no diminution in proliferative capability. Furthermore, it was unexpectedly discovered that these cells still synthesize β and γ-crystallins as monitored by immunoblot assay, indicating that the immortalizing event has not altered the cells normal differentiating function. These cells may be an important model system for studying human lens-specific physiology, and to investigate the role of the lens epithelium in cataract formation.
In one aspect the invention involves the formation of an immortalized cell line, which comprises a tissue cell line infected with a hybrid adenovirus/SV40 which propagates in vitro.
In another aspect, the invention involves a cell culture capable of expressing β-crystallin, γ-cystallin and mixtures thereof obtained by infecting epithelial cells with an expressing vector of a hybrid adenovirus/SV40.
A further embodiment involves a method for producing an immortalized cell line, which comprises culturing an epithelial cell line with a hybrid adenovirus/SV40 to form an immortalized cell line capable of propagating in vitro; and collecting the immortalized cell line.
Additional embodiments of the invention involve antibodies immunoreactive with the immortalized cell line; peptides produced from the immortalized cell line and particularly peptides selected from the group consisting of βH-crystallins, and γ-crystallines (β5-crystallins), γS-crystallins, γC-crystallins, γD-crystallins and mixtures thereof.
Also included as a further aspect of the invention is a method for assaying lens inhibitory drugs, which comprises reacting the drugs with an immortalized epithelial cell line and determining the reactivity of the drugs on primary and secondary cataract formation, as well as a diagnostic assay which comprises as an essential component the immortalized epithelial cell line. Another embodiment involves the formation of cell lines for the study of cataractogenesis.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a photomicrograph of infant human lens epithelial cells.
FIG. 2 is a photomicrograph of lens epithelial cells after infection with a hybrid adenovirus (Ad12-SV40).
FIG. 3 is a growth curve for the cell line infected by the virus.
FIG. 4 is a photomicrograph of immortalized cells after 19 passages.
FIG. 5 is a photomicrograph of the mammalian SV40 antibodies to large T antigen immunoreactive to an immortalized cell line.
FIG. 6 is a photomicrograph of control uninfected cells treated with monoclonal antibody to SV40 large T antigen.
FIGS. 7 and 8 are an analysis of protein from cultured immortal cells.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The human lens is a unique system for examining the relationship between gene expression and differentiation since populations of quiescent, dividing, differentiating and terminally differentiated cells are spatially segregated. It has been suggested that damage to the genome of lens epithelial cells by exogenous agents such as UV radiation, or other forms of oxidative stress may initiate or potentiate cataract formation. It is therefore important to investigate the physiology of the normal human lens epithelium and study its response to cataractogenic agents. These studies have been hindered by the lack of human lens epithelial cell lines that provide a homogeneous population of cells for the study of human lens specific functions such as expression of crystallin genes.
The present invention relates to the unexpected discovery of a human cell line with the capability to propagate indefinitely in long-term culture by the incorporation of the SV40 large T antigen into the genome of lens epithelial cells. These cell line have a stable epithelial morphology and continue to produce lens β and γ-crystallins, two proteins that are characteristic of lens cell differentiation in vivo and have been identified as β-5 and γD in the B-3 cell lines which has been deposited at the American Type Culture Collection, Rockville, Md. 20852, USA, on Jul. 27, 1993, as "cell line from human infant lens epithelium B-3", ATCC No. CRL 11421, in accordance with the Budapest Treaty.
Immunoprecipitation and SDS-PAGE tests suggest that the immortalized cells synthesize a β-crystallin polypeptide of molecular weight 24 kD, and a γ-crystallin of molecular weight 21 kD. β-Crystallins isolated from human lens fibers contain two polypeptides of molecular weights 24 and 26 kD, and the human monomeric fraction contains three polypeptides of molecular weights 24, 21 and 19 kD, corresponding to γS, γC and γD-crystallins, respectively. It is believed that the 24 kD protein of the immortalized human lens epithelial cells that immunoprecipitated with the βH-crystallins antibody is 62 5-crystallin and the 21 kD protein immunoprecipitated by the γ-crystallin antibody is γC-crystallin.
The human lens epithelial cell lines prepared by the present invention are capable of expressing endogenous crystallin genes while retaining the capability to propagate indefinitely in short population doubling times by immortalization with a virus. These cell lines present an important model for the study of human lens epithelial cell differentiation and its pathological manifestations in cataract and other disease states. These cells are useful for the assay of inhibitory drugs to prevent primary and secondary cataract formation, eye-related toxicology studies, and development of specific cell markers and immunodiagnostic tests useful for the clinical assessment of cataract development.
It is known that much of the landmark work in the study of mammalian genes came from working with tumor viruses. Tumor viruses infect mammalian cells, insert their own genetic material, and hijack the cellular biosynthetic machinery to manufacture more viruses. Often viral multiplication kills the cell. Sometimes the presence of tumor virus genes permanently alters the growth properties of an infected cell, transforming it into a tumor cell. Tumor viruses attracted the attention of researchers for several compelling reasons. Their genomes, which programs both viral life cycle in cells and the structural components of the virus itself, are often astonishingly small--the smallest DNA tumor viruses comprise a handful of genes packed into only 5000 bp. Within this small stretch of DNA lies the information for switching viral genes on and off in an ordered fashion, for replicating the vital genome, for assembling new virus particles, and for converting a normal cell into a cancer cell. Before recombinant DNA, these viruses, which could be purified in large quantities provided the only source of purified genetic material--DNA for some viruses, RNA for others--that functioned in mammalian cells.
The earliest gene transfer experiments were done with DNA tumor viruses such as the monkey tumor virus SV40, viruses whose genes are encoded in DNA just as cellular genes. DNA was isolated from purified viruses and introduced into cultures of uninfected cells. These cells eventually produced fully infectious viruses. This DNA-mediated transfer of infectious virus was dubbed transfection, to distinguish it from infection, the natural route of entry for viruses.
Applicants have unexpectedly discovered a hybrid method that uses infection to get DNA into cells and a viral protein to replicate it once inside to render the cells immortal and produce the β and γ-crystallin proteins. The mode of action, while not completely known, appears to involve the integration of a hybrid adenovirus/SV40, namely AD12-SV40 into the cell line. The cells then produce the viral T antigen protein which triggers replication of the viral DNA by binding to the cells DNA sequence.
In this way, an immortalized cell line is produced which comprises a tissue cell line infected with a AD12-SV40 which propagates in vitro. The preferred cell line is lens epithelial cells whereas the preferred hybrid adenovirus/SV40 is Ad12-SV40. The immortal cell lines are characterized by their ability to synthesize β-crystallins, and γ-crystallins and mixtures thereof and has been identified as B-3. Particular proteins having mean average molecular weights between 20-30 kD have been identified which react with antibodies to βH-crystallins and γ-crystallins.
Furthermore, the cell line produces a polypeptide having a 24 kD molecular weight material which appears to be β5-crystallin. Other peptides having molecular weights of 24, 21 and 19 kD are present in the human lens fibers produced which correspond with γS-crystallins, γC-crystallins and γD-crystallins. Accordingly, the invention provides a way to produce a peptide selected from the group consisting of βH-crystallins, γD-crystallins, γ5-crystallins, γS-crystallins and mixtures thereof, which may be isolated and purified for further use.
The invention also provides a novel, and simple immunoassay test system especially adapted for the detection and determination of a component of an antigen-antibody reaction. While the test protocol is not critical, any conventional tagging means, such as EIA, ELISA, RIA, may be used as well as conventional assays, such as straight assays, sandwich assays and sequential assays. The general principle of one procedure uses as a test reagent a given amount of one component of said reaction bound to the surface of a solid carrier, and as a second reagent, a given amount of the same component covalently linked to an enzyme. A diagnostic test for the detection and determination of the component of an antigen-antibody reaction can then be formed comprising an antibody to the immortal cell line bound to a solid carrier, a substance having the same immunological properties as the antibody linked to an enzyme or other marker (biotin-avidin and so forth) and optional binding partner of the component to be determined. Optional stabilizers may also be present to stabilize the antibodies during storage and/or testing procedures.
It has been found that antibodies can be conventionally produced to the novel immortal cell lines which are both monoclonal and polyclonal. Preferred monoclonal and polyclonal antibodies couple with the hybrid adenovirus present in the cell line, with the immortal cell line or proteins produced by the cell lines. Such antibodies as well as commercially available antibodies can be used in the immunoassay test systems of this invention, either alone or in combination.
A particularly preferred assay would involve assaying lens inhibitory drugs to determine their effect upon the lens tissue. A preferred procedure would involve reacting the active drugs to be tested with the epithelial immortalized cell line and determining the reactivity of the drugs on primary and secondary cataract formation. Such a testing protocol or assay procedure can be used for screening experimental drugs prior to use and for testing drugs for use with the eye for eye related taxocology. The invention also contemplates a method for assaying cytotoxicity of polymer coatings on intraoccular lenses.
The following examples are given to illustrate the invention, but are not to be limiting thereof. All percentages given throughout the specification are based upon weight unless otherwise indicated. All peptide molecular weights are based on mean average molecular weight unless otherwise indicated.
EXAMPLES
Primary cultures
Human lenses were obtained within 24 hrs. from 5-12 month old patients who underwent treatment for retinopathy of prematurity. A small cut was made in the posterior capsule of the lens, the free edge was grasped with forceps and the capsule with attached epithelium was cut into 2 or 3 fragments and each fragment was placed in a separate dish. The milliliters of minimum essential medium (MEM by Sigma) containing 20% fetal calf serum (by Sigma) and 50 μg/ml gentamicin were added to the culture. The cultures were maintained at 37° C. in a water-saturated air atmosphere containing 5% CO 2 . Medium was changed twice weekly. The cells were routinely examined using a phase-contrast microscope.
Vital infection
After the primary cultures achieved confluence, the cells were subcultured using Trypsin-EDTA according to conventional procedures. See, for example, R. Ian Freshney. "Culture of animal cells. A manual of basic technique"; Chapter 10, --132-134. John-Wiley, New York (1987), which is incorporated herein by reference in its entirety. The secondary cultures were passaged again to confluence, into 100 mm plates. At 60% confluence, cells in the tertiary culture were infected with a 1:10 dilution of Ad12-SV40, diluted with culture medium MEM (minimum essential medium by Sigma) and incubated for 24 hours. At this time, the culture medium MEM containing 20% fetal bovine serum was removed, and 10ml fresh medium MEM containing 20% fetal bovine serum (FBS) was added to the cultures. Cells were allowed to grow for one week in a water-saturated air atmosphere containing 5% CO 2 and subcultured. After each passage, 24 hour collections of the culture medium were assayed for viral activity by a highly sensitive plaque assay.
Proliferation of immortalized cells
To determine the proliferative ability of the infected cells, 50,000 cells were plated in 60 mm plates (standard tissue culture-treated corning plates), 3 replicates for each time point, and the number of cells were counted using a Coulter counter. The growth assay was done over a period of 10 days, at which time the cultures were confluent.
Population doubling levels (pdl). To calculate pdl, the following equation was used:
N.sub.f /N.sub.o =2.sup.x
where x=number of population doublings, N f =final number of cells and N o =number of cells seeded into the plate initially. x=log (N f /N o )/log 2. After each passage, x was added to the previous population doubling level to get the new pdl.
Immunohistochemistry
Cells were plated in 24 well plates, grown to 60% confluence, and fixed with 1 ml of 70% ethanol for 15 minutes. After the addition of 200 μl of 0.05M Tris-Cl, pH 7.4, cells were incubated with the primary antibody (monoclonal mouse IgG for SV40 T antigen, Onocogene Science, Uniondale, N.Y.) at a dilution of 1:20 wash buffer for 1 hour. After 3 washes with wash buffer, cells were incubated with a biotin-labelled secondary antibody (rabbit anti mouse IgG from Dakopatts, Denmark) for 15 minutes at room temperature. Cells were then washed with wash buffer, incubated with avidin-peroxidase for 1.5 minutes, washed 3 times with wash buffer, and treated with freshly prepared substrate (diaminobenzidine) for 15 minutes. After extensive washing, cells were hydrated in wash buffer (0.05 M Tris. Cl., pH 7.4) and observed in a phase-contrast microscope.
SDS-PAGE and immunoblotting
Cells were lysed at 4° C., centrifuged at 10,000 g and the supernatants treated with the primary antibody. The cells immunoprecipitated using recombinant Protein G coupled to Agarose beads and the immune complexes were collected by centrifugation, washed with lysis buffer and suspended in 200 μl of SDS-PAGE buffer containing 50 mM-Tris-Cl, pH 6.8, 2% SDS, 1% 2-mercaptoethanol, 10% glycerol and 0.1% bromophenol blue. Electrophoresis was performed using 10% acrylamide gels according to Laemmli. See Laemmli U. K., "Cleavage of Structural Proteins During the Assembly of the Head of Bacteriophase T4. Nature 1970; 227:680-685 incorporated herein by reference. After immunoblotting on nitrocellulose membranes, the blots were probed with 125 I-labelled Protein A.
Polyclonal antibodies for the crystallins were prepared by immunizing rabbits with purified calf lens βH-crystallin using conventional procedures. Antibody to γ-crystallin was obtained by immunizing rabbits with the monomeric protein fraction from infant human lenses using conventional procedures. The antibodies were isolated and purified from primary rabbit serum from animals infected with Calf βH or γ or human monomeric protein.
Results
Capsule-epithelium fragments obtained from infant human lenses attached to the culture dish, and cell outgrowth was evident within 3 days after the initiation of the primary cultures. The primary cultures were allowed to grow to confluence and subcultures (1:2) for two passages. FIG. 1 shows that the cells maintain a typical epithelial morphology after the first passage.
Cells were then infected with the AD12-SV40 virus typically after a second passage achieved 60% confluence. The passage at which the cultures were infected did not appear to affect their immortalization. One week after virus infection, with adenovirus/SV40; population doubling level (pdl)=1.9, the infected cells continued to propagate to confluence, but the noninfected cultures showed diminished growth and failed to achieve confluence. Virus-infected cells ceased to produce intact virus in culture supernatants after 6-7 passages as shown by a plaque assay. Infected cells maintained their epithelial morphology and continued to grow to confluence as shown in FIG. 2. (Confluent monolayer of cells at passage 7 after virus infection, day 3 of culture; number of cells initially plated, n=6.6×10 5 , pdl=15.6.) Cell cultures continued to maintain epithelial cell morphology in passage 8, second day of culture, and exhibited areas that were translucent and may be `lentoids`. Non-confluent regions of the culture were also dense and translucent (passage 19, pdl=41.6, n=2.4×10 5 ). Some areas of the culture showed extensive aggregation of cells which were translucent, notably in cultures older than one week. Freezing the cells using 95% fetal calf serum and 5% DMSO using standard techniques did not alter cell viability.
Cells were routinely subcultured after they reached confluence (about 7 days). The growth potential of the virus-infected cells was studied by plating 5×10 4 cells in 60 mm culture dishes incubated in MEM containing 20% FCS and the number of cells on days 1-10 was determined. FIG. 3 shows the growth curve for the virus infected cells in passage 7. Cells in passage 7 (pdl=15.6) were enzymatically removed from the plates. The total number of cells was determined at specific times. (Mean±SEM, n=3). The cells achieved four population doubles on day 7, and did not exhibit a decrease in growth potential at passage 22. These cultures have achieved population doubling levels of 40-50 and show no diminution of proliferation as a function of population doubling levels.
The effect of long-term culture on virus-transfected cells was studied with the results shown in FIG. 4, which are phase contrast micrographs of virus-infected lens epithelial cells in passage 19 after 30 days in culture. The monolayer begins to detach from the edges of the culture dish. Upon subculture, cells outgrow from the sheets to form a monolayer on plate coated with 2 μg/cm 2 fibronectin (Pdl=41.6). These sheets of cells were viable, and when removed from the plates and placed in fresh medium showed renewed attachment to the plate. The reattached cells continued to propagate into confluent cultures.
In FIG. 5, the immunohistochemistry of cultured lens epithelial cells using a mouse monoclonal primary antibody to SV40 large T antigen is demonstrated. Nuclear staining in the virus-infected cells indicates that the immortalized cells are T antigen-positive. Nearly 100% of the proliferative cells in the confluent monolayer are T antigen positive, indicating that the entire surviving population of cells contains the viral genome responsible for proliferation. Control cells without virus transfection treated with the monoclonal antibody showed faint cytoplasmic staining in the cells. FIG. 6 shows non-transfected control cells without primary antibody (C and D, infected cells, n=1.1×10 5 , pdl=3.8, passage 2).
In FIGS. 7 and 8, the analyses of proteins by SDS-PAGE and Western blotting showed that the immortalized cells produce proteins of molecular weights between 20-30 kD, which react with the antibodies to βH- and γ-crystallins proteins that are markers for cell differentiation in the lens epithelium. The Figures depict the following lanes: lane 1, molecular weight markers; lane 2, cells in the third passage after virus infection immunoblotted with an antibody to calf lens βH-crystallin; lane 3, cells in passage 3 (pdl=9.9) after virus infection immunoblotted with an antibody against infant human lens γ-crystallin; lane 4, human corneal fibroblast cells as a control immunoblotted with βH-crystallin antibody; lane 5, human corneal fibroblast cells as a control immunoblotted with an antibody to human lens γ-crystallin; lane 6, human lens epithelial cells in passage 17 immunoblotted with antibody βH-crystallin (pd1=38.6).
The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications are intended to be included within the scope of the following claims. | An immortalized epithelial lens cell line obtained from human lens epithelial cells infected with hybride adenovirus/SV40 (Ad12-SV40), and methods for making and using the cell line are disclosed. | 2 |
FIELD OF THE INVENTION
The present invention relates to the attachment of wear members, such as heel shrouds, to surfaces subject to abrasive wear, such as earth moving buckets.
BACKGROUND TO THE INVENTION
Buckets for earth moving equipment, such as excavators, are subject to a high degree of abrasive wear. This wear is particularly pronounced at a leading edge of the bucket, where ground engaging tools such as adaptors and teeth are used to penetrate matter being dug. It is also found at bucket corners and heels, although wear in these areas is not as pronounced as at the leading edge.
In order to prolong the working life of a bucket, and to retain structural strength in the face of this wear, it is common practice to fix replaceable wear members to those parts of the bucket most subject to wear. Traditionally wear members such as teeth, wear strips and heel shrouds have been welded into place on a bucket.
Although the welding of wear members to buckets provides a secure means of attachment, it has significant practical difficulties. Replacement of worn members requires the cutting out of the worn member, and the fitting and re-welding of a new member in its place. Such metal-working operations require specialised equipment and trained boilermakers.
Where the bucket is being employed remotely, the removal of the bucket, transportation to a suitable workshop, replacement of the worn member and transportation back to the remote location can result in a significant time delay, and thus a loss of production. As excavators are often highly expensive, the underutilisation caused by the need for bucket repairs has a significant economic consequence.
In response to this problem, methods of mechanically attaching ground engaging tools to the leading edge of the bucket have been developed. An example of such a method is disclosed in the international patent application published as number WO02/12642, in the name of a predecessor of the present applicant.
Generally, known methods of mechanically attaching ground engaging tools to a bucket leading edge involve providing the ground engaging tool with a channel which locates about the bucket leading edge, and then clamping or bolting the ground engaging tool in a particular position along the bucket edge.
The geometry of this arrangement greatly assists in the attachment of ground engaging tools. The principle forces to which the tools are subjected are shear forces and compressive forces, and generally speaking these forces are transmitted directly to the bucket leading edge, rather than through the clamp or bolt being used. The mechanical attachment is thus only really required to prevent lateral movement of the tool along the bucket edge, or the pulling away of the tool from the bucket edge.
There have been relatively few attempts to provide a mechanical attachment of heel shrouds to excavator buckets. There would appear to be two reasons for this. Firstly, the rate of wear of heel shrouds is less than that of ground engaging tools, and thus the economic advantage of mechanical attachment, whilst significant, is not as great as for ground engaging tools at the bucket leading edge. Secondly, and perhaps more significantly, the geometry of heel shroud attachment is much less promising than at the bucket leading edge.
Heel shrouds must be mounted around corners or heels of the bucket. As such, there is no lip for them to clamp around. In other words, the angle included by a heel shroud is in the order of 90°, as opposed to an included angle of about 20° typical for ground engaging tools. Any force acting on the heel shroud, except for a direct compressive force, will act directly on the attachment system on at least one face. This places significant stress upon the attachment system. To date, therefore, welding has proved the only suitable method of attachment.
Research by the applicant has revealed an attempt to overcome this problem by bolting of heel shrouds to bucket corners and heels. This technique has several drawbacks. Firstly, the drilling of bolt holes within the bucket can reduce the bucket strength. Secondly, there is a tendency for bolts to deform under load. When this occurs, it can be impossible to remove a bolt using normal mechanical tools, and it may be necessary to cut the bolt from the bucket. This, of course, eliminates any advantage gained by the use of such bolts.
The present invention seeks to provide a means of mechanically attaching a heel shroud to an excavator bucket which does not require bolting through the bucket walls.
SUMMARY OF THE INVENTION
In accordance with a first aspect of the present invention there is provided a wear member assembly providing attachment of a wear member to a wear member receiver on an outer surface of an earth moving apparatus member,
the wear member assembly including a wear member, a wear member receiver having at least first and second contact portions and at least one aperture to receive at least one wear member locating member of a wear member assembly,
a releasable attachment mechanism arranged to releasably attach the wear member to the receiver, including at least one moveable attachment member and at least one respective fastening means such that actuation of each of the fastening means moves the associated attachment member to apply a retaining force to one of the contact portions of the receiver and causes the respective wear member locating member to apply a retaining force to the other of the contact portions of the receiver,
at least one of the receiver first and second contact portions has a tapered face and the corresponding wear member locating member or attachment member has a taper such that contact between the wear member locating member taper or attachment member taper and a corresponding one of the wear member receiver tapered contact portions causes the wear member to positively locate to the receiver thereby releasably retaining the wear member to the outer surface of the earth moving apparatus member.
In accordance with a further aspect of the present invention there is provided a wear member assembly for attachment to a wear member receiver provided on an outer surface of an earth moving apparatus member,
the wear member receiver having at least first and second contact portions and an aperture to receive a wear member locating member of a wear member assembly,
the wear member assembly including a releasable attachment mechanism arranged to releasably attach the wear member to the receiver,
the wear member assembly having a moveable attachment member and a fastening means such that actuation of the fastening means moves the attachment member to apply a retaining force to one of the contact portions of the receiver and causes the wear member locating member to apply a retaining force to the other of the contact portions of the receiver,
at least one of the receiver first and second contact portions has a tapered face and the wear member locating member or the attachment member has a corresponding taper such that contact between the wear member locating member taper or the attachment member taper and a corresponding one of the wear member receiver tapered contact portions causes the wear member to positively locate to the receiver thereby releasably retaining the wear member to the outer surface of the earth moving apparatus member.
The invention has been envisaged with the earth moving apparatus member being a bucket, such as an excavator bucket, the outer surface being a bucket corner or bucket heel and the wear member being a heel shroud. The base portion may be the floor of the bucket, or may be the curved, rear portion of the bucket.
Both the wear member locating member and the attachment member may have a respective tapered contact surface or face, and the receiver may have respective tapered first and second contact portions, preferably being surfaces or faces, such that actuation of the fastening means causes the locating member and the attachment member to lift and positively retain the wear member to the wear member receiver.
Tapered contact urges the wear member locating member and attachment member to move (preferably to slide) relative to the tapered first and second contact portions (surfaces or faces) of the receiver and move upwards thereby causing the wear member to be retained to receiver located on the earth moving apparatus member.
The tapered face(s) ensures that the wear member is lifted to positively mate against the wear member receiver. The wear member receiver may otherwise be known or called an adapter because it allows the mounting parts of the wear member to connect the wear member to the earth moving apparatus (e.g. bucket). This is important when impact is directed through the wear member (heel shroud) so that all forces transfer to the earth moving apparatus without loose movement of the wear member that might otherwise damage the wear member, earth moving apparatus or the connection between the two.
Although the present specification uses the terminology “taper”, “tapered” or “tapered face(s)”, it is to be understood that such references include terms such as “chamfer” and “chamfered”. The “taper” defines the locating member and the attachment member as having an overhang or broader top that narrows further down to the respective base. This “taper” may provide a flat face or convoluted face.
The wear member may include an aperture to receive therethrough at least part of the wear member attachment member. This enables the wear member attachment member to extend into the aperture of the wear member receiver for engagement therein.
The wear member locating member may have a bearing surface against which a portion of the fastening means bears and applies a force.
The fastening means may include one or more screw thread fasteners, such as bolts.
The through aperture of the wear member receiver may be bounded at opposed sides thereof by side portions. One or more of these side portions may include a respective projection portion, the projection portion arranged to support a corresponding wear member locating member projection. The projection portion of the respective side portion may be formed by a step in the material of the side portions. The projection(s) assists in initially locating the wear member to the wear member receiver and subsequently initially holding the wear member loosely in place until the fastening means is tightened.
The wear member attachment member may include a moving member or locking member, such as a sliding nut), which may include the attachment member tapered face. In use, the attachment member may move away from the locating member so as to expand the effective size of the attachment and locating members of the wear member assembly. Thus, these components may act as an adjustable boss to releasably attach the wear member to the receiver.
The wear member receiver may be welded or otherwise fastened to the underside of the earth moving apparatus. Alternatively, the wear member receiver may be formed integral with the earth moving apparatus.
The wear member may include a wear member body having a main body portion that, in use, mounts to an underside of the earth moving apparatus, and optionally a side body portion that, in use, extends at least partway along a side of the earth moving apparatus. The wear member body main and side body portions may be formed as a one piece components, such as by casting metal.
The main and side body portions may form an internal corner generally at right angles, which corner may include a recess or channel therealong arranged to accommodate an external corner edge of the earth moving apparatus. This also reduces corner contact between the body and the earth moving apparatus directly at that corner and reduces potential for fracture due to working forces at the body internal corner, thus maintaining the life of the wear member.
The wear member may include multiple locating members, preferably two. One or more of the locating members may include a respective said tapered face. The wear member may include a corresponding aperture therethrough for each respective locating member. Each such aperture may receive therethrough a respective fastening means.
Each locating member may have one or more of the projections to aid in locating and initially retaining the wear member in position until fastened using the fastening means.
One or more of the wear member side portions may include a respective protruding portion to project, in use, into a corresponding recess in the wear member receiver or earth moving apparatus. This further helps to position the wear member to the receiver but also helps transfer working loads through the wear member to the earth moving apparatus to prevent the wear member being moved or removed from its attached position.
One or more of the locating members may have an oblique face, which may also be incorporated in the tapered face. The wear member receiver may have a respective corresponding oblique face. Thus, whilst the fastening means urges the locating member and therefore wear member longitudinally relative to the earth moving apparatus, forces through the contacting oblique faces urge the wear member to move laterally relative to the earth moving apparatus.
Likewise, one or more of the attachment members may also include an oblique face, which may be the tapered face. This further assists in ensuring the wear member positively locates and attaches to the earth moving apparatus.
The wear member may have at least one raised elongate wall or shoulder portion extending along one or more respective sides of the aperture. The at least one shoulder portion may act, in use, to transfer shock and/or load through the wear member to the earth moving apparatus, and may also provide additional wear member locating benefits. The wear member receiver may include a corresponding at least one shoulder portion receiving recess. Alternatively, or in addition, the shoulder portion(s) may be provided on the wear member receiver or earth moving apparatus, and the receiving recess(es) on the wear member. The shoulder portion(s) may be elongated and may be discontinuous or segmented in length.
The wear member may include a mounting grip or knuckle extending forward of the body. This mounting grip or knuckle provides a lifting/handling point for use in initially positioning or removing the wear member to/from the earth moving apparatus. This also may provide a degree of protection for the head of the fastening means within the aperture in the outside face of wear member.
The locating member (also known as a “boss”) may have side projections to help engage with the receiver. The receiver may have a platform area around the aperture therethrough, the aperture for receiving therethrough the locating member. The platform may support the side projections of the locating member. This support helps sustain impact during loading of the earth moving apparatus (e.g. bucket).
At least one spacer may be provided to locate between the locating member and the attachment member. At least one of these spacers may have an aperture through which the fastening means passes.
The at least one spacer may provide friction to the fastening means. For example, the spacer may include an aperture including a friction material, such as nylon or other plastics or soft metal material, that provides some resistance to the fastening means coming undone through vibration or normal working forces. The friction material will hold the fastening means fastened until released when required.
BRIEF DESCRIPTION OF THE DRAWINGS
It will be convenient to further describe the invention with reference to a wear member, being a heel shroud in a preferred embodiment of the present invention. Other embodiments are possible, and consequently, the particularity of the following discussion is not to be understood as superseding the generality of the preceding description of the invention. In the drawings:
FIG. 1 shows an exploded view of components of a wear member assembly for mounting to an earth moving apparatus member according to an embodiment of the present invention.
FIGS. 2 a to 2 e show components of the embodiment shown in FIG. 1 .
FIGS. 3 a to 3 d show a wear member of an embodiment of the present invention.
FIG. 4 shows an alternative form of wear member according to a further embodiment of the present invention.
FIGS. 5 a to 5 c show a wear member assembly mounted to a receiver (adapter) according to an embodiment of the present invention.
FIG. 6 shows a plan view of a wear member assembly mounted to the corner of a bucket of an earth moving apparatus.
FIGS. 7 a and 7 b show sectional views A-A and B-B through the embodiment shown in FIG. 6 .
FIGS. 8, 9 and 10 show alternatives form of wear member according to further embodiments of the present invention.
FIGS. 11 a to 11 e show alternative forms of a wear member receiver according to an embodiment of the present invention.
FIGS. 12 a to 12 c show views of an alternative form of attachment member according to an embodiment of the present invention.
FIG. 13 shows an alternative form of the wear member according to a further embodiment of the present invention.
FIG. 14 shows a plan view of an alternative wear member assembly mounted to the corner of a bucket of an earth moving apparatus.
FIGS. 15 a and 15 b show sectional views A-A and B-B through the embodiment shown in FIG. 6 .
FIGS. 16 a to 16 e show an assembled wear member assembly and individual components of that assembly according to a further embodiment of the present invention.
FIG. 17 shows an exploded view of a wear member assembly according to a further embodiment of the present invention.
FIGS. 18 a to 18 e show various views of a receiver (adapter) according to a further embodiment of the present invention, the receiver having tapered and oblique contact portions or faces.
FIG. 19 shows an exploded view of an alternative embodiment of the present invention for mounting to a corner of an earth moving bucket.
FIG. 20 shows an exploded view of a further alternative version of the present invention.
FIGS. 21 and 22 show alternative wear members with multiple locating members and capacity to receive multiple corresponding attachment members, the version in FIG. 21 having locating members with tapered faces and the version in FIG. 22 having locating members with tapered and oblique faces.
FIG. 23 shows an exploded perspective view of a wear member with multiple locating members and corresponding multiple attachment members and multiple fastening means, being an arrangement for releasably mounting the wear member to a receiving member, being an assembly according to an embodiment of the present invention.
FIGS. 24 a and 24 b show a respective receiver ( FIG. 24 a ) and wear member ( FIG. 24 b ) according to a further embodiment of the present invention incorporating additional locating means aiding installation of the wear member.
Specific version of embodiments and components of the present invention will hereinafter be described.
DESCRIPTION OF PREFERRED EMBODIMENT
FIG. 1 shows a portion of an excavator bucket corner 10 having an inner surface 12 and an outer surface 14 . The outer surface 14 has a base portion or floor 16 which extends inwardly of the bucket leading edge (not shown), and a side portion 18 .
The bucket corner portion 10 has a wear member receiver 20 affixed to the most outward part of the base portion 16 of the outer surface 14 . In this embodiment of the present invention, the wear member receiver is welded to the bucket corner portion 10 , but it will be appreciated that the receiver may be bolted, riveted or formed integrally with the bucket corner e.g. in a casting process. The receiver 20 has an aperture 78 arranged to receive therethrough at least a portion of a locating member 26 and attachment member 44 .
A wear member assembly 22 includes a wear member 24 having a locating member 26 integral to a body 28 formed of a main body portion 30 and a side body portion 32 extending generally perpendicular to the main body portion. The side body portion may have a lip 34 arranged to engage over a shoulder portion 36 of the receiver.
The wear member has an aperture 42 through the main body portion that forms a base or platform section. An attachment member 44 is arranged to pass up through the aperture 42 . A fastening means in the form of a bolt 46 is arranged to pass through an aperture 48 in a front face of the wear member. The bolt includes a thread that engages with an internal thread of an aperture 50 through the attachment member once the member is in place through the aperture 42 in the main body portion of the wear member. With the wear member 24 positioned against the receiver 20 , a tapered contact face 52 on the locating member 26 engages with a corresponding tapered contact face 54 on the receiver. Rotation of the bolt causes the attachment member 44 to move away from the locating member. The attachment member has a tapered contact face 56 and to engage with a corresponding tapered contact face 58 on an inner surface of the receiver. A distal end 60 of the bolt 46 can have a contact end 62 that is free to rotate relative to locating member of the wear member. Alternatively, the fastening means (e.g. bolt 46 ) may be a one piece component. This contact end includes an impact head arranged to impinge against a rear face 64 of the locating member 26 . It will be appreciated that as the bolt is rotated, the attachment member advances towards the side body portion of the wear member and impinges against the internal tapered contact face 56 of the receiver. This action also causes the locating member to be forced away from the attachment member as the bolt advances through the aperture of the attachment member by contact of the impact head 64 of the bolt against the forward contact face 65 of the locating member. The locating member is thereby forced into engagement against the tapered contact face 54 of the receiver. The arrangement of tapered faces and respective contact therebetween causes the wear member to lift up against the receiver to be positively held in place. This presents loose movement of the wear member and helps to ensure load forces are transferred effectively to the earth moving apparatus (e.g. a bucket or shovel) through the receiver, and reduces premature wear or failure of the assembly.
FIGS. 2 a to 2 d show an embodiment of the present invention assembled and as separate components. FIG. 2 a shows the assembly mounted to a receiver 20 . It will be understood that the receiver would be attached to the underside of earth moving apparatus, such as a bucket. The locating member 26 (also known as a ‘boss’) is engaged against a contact face 54 of the receiver. The attachment member 44 is engaged against an opposite contact face 58 of the receiver. The bolt 46 passes through the front face of the wear member 24 , passing through the attachment member and impinging against the locating member.
The locating member has side projections 66 , 68 . These side projections are supported on corresponding side projections 70 , 72 extending from side portions 74 , 76 of the receiver. In use, the wear member is initially presented up to the receiver such that the side portions 66 , 68 of the locating member 26 pass into the wider portion 77 of the aperture 78 and then the wear member moved so that the locating member side projections 66 , 68 are over the receiver side projections 70 , 72 . This initially supports and stabilises the wear member whilst attachment member and fastening means are put into place and the wear member fully engaged in place. This arrangement of projections prevents the wear member dropping out until locked into place. The wear member 30 includes a force transfer face 33 on an upper surface of a wall portion 84 extending upwardly around the periphery of the main body.
FIGS. 3 a to 3 d show detail of the wear member 28 shown in FIG. 1 .
FIG. 4 shows an alternative embodiment of a wear member 81 of the present invention. This wear member is similar to the wear member 28 shown in FIG. 1 except the locating member 82 is reduced in width compared to that in FIG. 1 , and the main body 30 has a force transfer face 33 on a wall portion 84 extending upwardly around the periphery of the main body. In use, this force transfer face contacts against the receiving member to transfer load forces from the wear member to the earth moving apparatus. This helps to provide rotational support to the wear member.
FIGS. 5 a to 5 c show the wear member 28 , 81 mounted in place to a receiver 86 welded 90 on a corner 88 of a bucket. FIG. 5 b shows a side view of the assembly in place against a bucket corner. In FIG. 5 b is shown the force transfer face 33 contacting the receiving member face 87 .
FIG. 6 shows a plan view of a section of a bucket of an earth moving apparatus, with the wear member 28 , 81 mounted in position to a receiver 20 , 86 welded to the underside of the bucket external surface.
FIG. 7 a shows a sectional view taken through section line A-A of FIG. 6 . FIG. 7 b shows a sectional view taken through section line B-B of FIG. 6 . The locating member 26 , 82 tapered contact face 52 is seen engaged against the corresponding tapered contact face 54 on the receiver. Rotation of the threaded bolt 46 causes the attachment member 44 to move away from the locating member face 64 . As the bolt advances through the attachment member, the distal end of the bolt 60 impinges against a contact surface 92 of the locating member. As the attachment member contacts and pushes against the receiver, this causes the locating member to more positively engage against the receiver, thereby locking the wear member to the receiver. Release of the bolt by counter rotation causes the attachment member to move back towards the locating member, thereby allowing the wear member to be released from the receiver for repair or replacement. Once the bolt is removed from the attachment member, the bolt can be drawn out through the front aperture 48 of the wear member and the attachment member withdrawn through the aperture 42 in the base 94 of the wear member. Thus components of the assembly can be replaced if they are worn or damaged, or otherwise reused.
FIG. 8 shows an alternative embodiment of a wear member 100 . Elongate projections 102 , 104 extend from the inner face 112 of the side body portion 114 along the sides of a recessed platform area 106 adjacent the locating member 108 and aperture 110 of the wear member. These wall or shoulder elongate projections are provided to extend into corresponding channels in the receiver to further positively locate and stabilise the wear member when mounted to the receiver. One of the elongate projections 104 has a taper or angled face 105 . This angled face may receive a resilient material, such as rubber or a rubber like material, to provide a more forgiving tolerance than plain metal alone. This arrangement also assists in transferring load forces to the bucket through the receiver, and assists in reducing damage from shear forces through the wear member.
FIG. 9 shows an alternative embodiment of the wear member 120 . The wall or shoulder elongate projections 122 , 124 are shorter in elongate extent than the corresponding projections in FIG. 8 . These extend approximately the longitudinal extent of the locating member 126 and the aperture 128 . The wall or shoulder elongate projections 122 , 124 each has a taper face 123 , 125 . The platform area 130 in this embodiment is not recessed; however the recessed platform arrangement may be adopted. The wall or shoulder elongate projections 122 , 124 have side projections 132 , 134 , each arranged to locate within a respective recess formed between the receiver and underside of the bucket, or within the receiver. This helps to initially locate and hold the wear member to the receiver, and provides an alternative or additional support mechanism to the side projections 66 , 68 on the locating member, similar to projections 70 , 72 of the receiving member.
The wear member shown in FIG. 10 is similar to that shown in FIG. 9 ; however the wall or shoulder elongate projections 122 , 124 extend along a majority of the platform area 130 without meeting the interior surface 112 of the side body portion 114 .
FIGS. 11 a to 11 e show various views of an embodiment of a receiver 20 of the present invention. FIG. 11 a is a top, plan view, FIG. 11 b a front end view, FIG. 11 c a bottom view, and FIGS. 11 d and 11 e are perspectives. Side projections 142 , 144 are shown extending into the receiver aperture 140 . The receiver includes an arcuate channel 146 to accommodate the fastening means (e.g. bolt) when the wear member is mounted to the receiver. The receiver includes a receiver rear tapered contact face 148 for mating with the tapered contact face of the locating member. The receiver also includes a front tapered contact face 150 for the attachment member to locate against.
An embodiment of the attachment member 44 is shown in FIGS. 12 a to 12 c . FIG. 12 a shows top, bottom, front and respective side views of the attachment member. The attachment member is essentially a nut with a threaded through aperture arranged to engage with a corresponding thread on the bolt 46 ( FIG. 2 e ) so that the attachment member moves along the bolt when the bolt is rotated one way or the other. The attachment member has a tapered face 56 arranged to engage over a lip 152 of the receiver. Preferably the attachment member tapered contact face 56 contacts a corresponding tapered face 150 of the receiver. However, it will be appreciated that the overhang 154 is sufficient to allow the attachment member to engage with a portion of the receiver bounding the receiver aperture 140 and prevent the wear member releasing from the receiver until the fastening means is released.
FIG. 13 shows an alternative embodiment of the wear member 160 . This embodiment includes bevelled extensions 162 , 164 of the bounding periphery 166 of the wear member. This bounding periphery 166 bounds a recessed platform 172 . The bevelled extensions 162 , 164 project from peripheral raised edges 168 , 170 of the bounding periphery 166 . These bevelled extensions assist in locating the wear member correctly to the receiver, which would have corresponding (bevelled) recesses either side thereof.
FIGS. 15 a and 15 b are respective sectional views taken along section lines A-A and B-B of FIG. 14 showing detail of an embodiment of an assembly according to the present invention.
FIG. 16 a shows an assembly 180 according to an embodiment of the present invention mounted to a corresponding receiver 182 . The wear member 184 includes a raised bounding periphery 186 . The locating member 188 has an oblique face 190 for engagement with a corresponding oblique face 192 on the receiver. Likewise, the attachment member 194 has an oblique face 196 angled in an opposite direction to that of the locating member, and which attachment member oblique face is arranged to engage with a corresponding oblique lip or face 198 of the receiver. These opposite angled oblique faces form a trapezium arrangement within the aperture 200 of the receiver and ensure that the wear member is biased sideways to positively engage towards the long side 202 of the trapezium and thereby lock in place. The bolt 204 is threaded into the aperture 206 of the attachment member 194 per other embodiments described. The combination of tapered and oblique faces of the respective locating and attachment members allows the wear member to take a greater load on one side than the other.
FIG. 17 shows an exploded view of the components of the assembly 210 and bucket corner 212 mounted receiver 214 . The components are similar to those shown in FIGS. 16 a to 16 e though the locating member 216 on the wear member 220 is narrower than the attachment member 218 . The attachment member 218 has respective tapered 224 and oblique 222 faces forming a respective attachment member compound face positive engaging mechanism to engage within the trapezium shaped aperture in the receiver. Likewise, the locating member 216 has respective tapered 228 and oblique 226 faces forming a respective locating member compound face positive engaging mechanism to engage within the receiving member aperture. The combination of compound faced locating and attachment members causes the wear member to forcibly bias to one side of the receiving member aperture as they impinge against associated compound faces of the receiving member.
FIGS. 18 a to 18 e show various views of a receiver 214 for releasably retaining the wear member assembly 210 of FIG. 17 . FIG. 18 e shows detail of the tapered and oblique faces 192 , 198 on the receiver for respectively engaging with the locating member and attachment member tapered and oblique faces.
FIGS. 19 and 20 show exploded views of an alternative embodiment of an assembly 230 of the present invention for mounting to a receiver 232 welded adjacent a corner 234 of an earth moving apparatus member, such as a bucket. This embodiment includes a spacer for positioning between the locating 238 and attachment 240 members. The spacer includes an aperture 242 for receiving therethrough a fastening means (e.g. bolt) 244 . In this embodiment, the wear member 246 side body portion 248 has a lifting or positioning member 250 , such as a loop (shown) or other projection, such as a hook or a recess. The spacer helps fill the space between the locating member and the attachment member and thereby prevent or reduce ingress of soil, rock or other contaminants into the assembly.
FIG. 21 shows a wear member 260 according to an alternative embodiment of the present invention. In such embodiments, the wear member includes multiple locating members 262 , 264 . Each locating member may have a corresponding aperture 266 , 268 adjacent thereto for receiving a respective attachment member (not shown). Alternatively, a single wide aperture may be provided that allows a single or multiple split attachment member(s) to be inserted therethrough. The single or multiple attachment member(s) has/have corresponding apertures therethrough to receive the respective fastening means (not shown). The wear member 260 has respective multiple front apertures 270 , 272 for the fastening means. In the embodiment shown, the locating members have tapered front contact faces 274 , 276 , and each has a single side projection 278 , 280 for engagement with respective side projections on the receiver. It will be appreciated that the receiver may have multiple apertures therethrough to receive the respective locating members and attachment members.
FIG. 22 shows an alternative embodiment of the wear member with tapered and oblique multiple contact faces 282 , 284 . These oblique faces are angled in the same direction so that the wear member is biased to one side relative to the receiver. The combination of tapered and oblique faces of the respective locating and attachment members allows the wear member to take a greater load on one side than the other. The raised edge around the periphery of the main body of the wear member should preferably fully mate against the underside of the receiver in order to best transfer impact forces to the receiver and thence to the bucket.
The side projections on the locating member insert up over the ‘wing’ projections within the aperture of the receiver. A tight fit helps sustain impact during loading.
During tensioning of the bolt and nut within the wear member, the tapered face of the nut will push the wear member forward and upward. The wear member moves upward up against the underside of the receiver due to the tapering faces of the nut and the locating member acting on the receiver contact points.
In use, the wear member is offered up to and initially engaged with the receiver (adapter). The attachment member (taper faced nut) is inserted into the wear member aperture from the underside of that member. Next, the bolt is inserted in through the front aperture of the wear member and rotated to engage with the nut. Tensioning the nut and bolt by rotating the bolt causes the nut to engage with the front internal part of the receiver. The bolt also forces the locating member away to engage with the rear internal part of the receiver. This tensions the wear member and holds it in place on the receiver. The angled (tapered) locating member (boss) and preferably the angled attachment member (nut) enable the wear member to withstand greater loads. The oblique faces on each also allow greater loads on one preferred side of the wear member.
The receiver may have one or more protrusions from a front thereof which, in use, engage into corresponding one or more recesses in the rear of the side body of the wear member. The assists in preventing the wear member moving and helps transfer frontal loads to the bucket.
The locating wings (side protrusions) on the locating member engage above side protrusions from the receiver into the receiver recess and allow the wear member to initially suspend from the receiver until the nut and bolt are inserted and engaged.
It will be appreciated that left and right hand wear member, nut, locating member and receiver may be required to accommodate the oblique face embodiments depending on their position on the bucket.
FIG. 23 shows the wear member 260 of FIGS. 21 and 22 in an exploded perspective view of an assembly according to an embodiment of the present invention. A receiving member has multiple apertures 290 , 292 . Each said aperture 290 , 292 is arranged to receive therein a corresponding one of the locating members 280 , 278 . Each aperture has a compound angle contact face 294 , 296 for contact with the corresponding compound contact face 304 , 302 (e.g. tapered and oblique multiple contact faces 282 , 284 ) of the respective locating member 262 , 264 . Each of the receiving member apertures 290 , 292 has a projecting portion 298 , 300 for supporting the corresponding projecting portion 278 , 280 of the respective locating member 262 , 264 . The corresponding twin attachment members 306 , 308 have compound angled faces 310 , 312 , with the oblique angle in an opposite direction to that of the respective locating member. When the wear assembly is assembled, the twin fastening means (bolts 314 , 316 ) extend through apertures 318 , 320 in the front of the wear member. These threadingly engage through respective threaded apertures 322 , 324 of the attachment means once the attachment means have been inserted into the respective apertures 326 , 328 in the main body portion of the wear member 260 . Distal ends of the bolts 328 , 330 impinge against a contact face 332 , 334 on the respective locating member. Further fastening causes the attachment members to travel towards the side body portion of the wear member and thereby engage against the forward edges or faces 336 , 338 of the apertures 290 , 292 in the receiving member 20 . Contact between the respective compound faces (tapered and oblique) causes the wear member 260 to bias to one side of the receiving member and thereby positively locate and assist in transferring load forces more efficiently and effectively to the earth moving apparatus.
FIGS. 24 a and 24 b show an alternative embodiment of the wear member and receiver of the assembly. The wear member 186 and receiving member (receiver) 182 are similar to those shown in respect of FIGS. 16 a to 16 c . The wear member 186 has the single locating member 188 with compound angled and tapered face to locate against a corresponding surface 192 forming a part of the aperture 200 in the receiving member. In this embodiment, the wear member 186 includes further installation engagement portions 340 a , 340 b each arranged and configured to engage with a respective installation receiving portion 342 a , 342 b on the outer periphery of the receiving member 182 . This arrangement assists in initially locating and supporting the wear member when installing the wear member to the receiving member. It will be appreciated that the wear member and corresponding receiving member (receiver) can be of any configuration falling within the scope of the present invention, and as shown in the accompanying figures and described above, though not limited to the specific embodiments shown and described in this application. Thus, the installation engagement and receiving portions can be provided on any embodiment of the present invention. When the wear member is initially mounted to the receiving member, and the locating member is placed into the aperture, the installation engagement portions include shoulders that are supported on the installation receiving portions that project from the body of the receiving member. Thus, width the locating member within the aperture of the receiving member and its leading face contacting the support face on the receiving member, and the installation engagement portions in place on the installation receiving portions, the wear member is initially supported on the receiving member and thereby on the lip or edge of a bucket of earth moving equipment. This feature helps support the wear member on the receiving member until the attachment mechanism with its attachment member(s) is operated to lock the wear member into place against the receiving member. The installation engagement portions also help transfer load forces to the receiving member, and thereby to the bucket, | A wear member assembly has a wear member, a wear member receiver with at least first and second contact portions and at least one aperture to receive at least one wear member locating member of the wear member. An attachment mechanism, releasably attaches the wear member to the receiver has at least one moveable attachment member and at least one respective fastening means. Actuation of each of the fastening means moves the associated attachment member to apply a retaining force to one of the contact portions of the receiver and causes the respective wear member locating member to apply a retaining force to the other of the contact portions of the receiver. At least one of the receiver first and second contact portions has a sloped or tapered face, and the corresponding wear member locating member or attachment member has a slope or taper, such that contact between the wear member locating member slope/taper or attachment member slope/taper and a corresponding one of the wear member receiver sloped/tapered contact portions causes the wear member to positively locate to the receiver when the releasable fastening means is actuated thereby releasably retaining the wear member to the outer surface of the earth moving apparatus member. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a communication system such as an asynchronous transfer mode (ATM) system, and more particularly, to a cell rate supervising system used in the communication sytem.
2. Description of the Related Art
Recently, ATM communication systems have been developed to realize a broadband integrated services digital network (B-ISDN).
In the ATM communication system, all multi-media information related to audio, video and data are stored in fixed length cells each formed by a header (5 bytes) and a payload (48 bytes). Since the cells have the same configuration, it is possible to multiplex, demultiplex and switch in the same network at different rates regardless of the kind of multi-media.
In the ATM communication system, if an abnormally large number of cells are supplied to a network, it is impossible to guarantee quality of service (QOS). This state is called a congested state. For example, assume that a connection is carried out between a first source terminal and a destination terminal via the network and a connection is carried out between a second source terminal and the destination terminal via the network. In this case, when a cell rate from the first source terminal to the destination terminal plus a cell rate from the second source terminal to the destination terminal exceeds a peak cell rate (PCR) from the network to the destination terminal, a congested state may occur in the network.
In order to suppress the generation of congested states, various ATM service classes, i.e., a constant bit rate (CBR) service, a variable bit rate (VBR) service, an unspecified bit rate (UBR) service and an available bit rate (ABR) service are defined in the ATM communication system.
In the CBR service, a fixed cell rate is allocated to each connection between a terminal and the network. Therefore, even if there are a plurality connections carried out for one destination terminal via the network, a total of such fixed cell rates of the connections are caused to be lower than a PCR from the network to the destination terminal, and therefore, a congested state may not be generated.
In the VBR service, a statistically-determined variable cell rate is allocated to each connection between a terminal and the network. Even in this case, even if there are a plurality connections carried out for one destination terminal via the network, a total of such variable cell rates of the connections are caused to be lower than a PCR from the network to the destination terminal, and therefore, a congested state may not be generated.
In the UBR service, a cell rate is determined by a terminal, that is, the control of cell rates by the network is not carried out. Therefore, a congested state may be generated.
In the ABR service, an allowed cell rate (ACR) is calculated in accordance with congestion information fed back from the network, and also, the ACR is changed between a minimum cell rate (MCR) and a PCR. That is,
MCR≦ACR≦PCR
Thus, a feedback operation using the congestion information is performed upon the ACR, which effectively makes use of the network.
The present invention is related to the ABR service.
Even in the ABR service, a congested state may be generated. That is, if a terminal has a trouble, the terminal may generate cells beyond the ACR. Or, if the MCR of the terminal is erroneously changed, the terminal may generate cells beyond the optimum ACR. Therefore, in order to monitor whether or not the cell rate of cells generated from each terminal is lower than the corresponding ACR, a cell rate supervising unit having a policing function is provided. In the ABR service, a dynamic generic cell rate algorithm (DGCRA) is used.
Note that a generic cell rate algorithm (GCRA), a virtual scheduling algorithm (VSA) or a continous-state leaky bucket algorithm (CSLBA) are used for the CBR service and the VBR service. For example, a usage parameter control (UPC) unit using these algorithms monitors excess traffic in a user-network interface (UNI), and a network parameter control (NPC) unit using these algorithms monitors excess traffic between networks in a network-node interface (NNI).
Returning to the DGCRA in the ABR service, an ACR is calculated in the cell rate supervising unit in the same way as in the terminal. Therefore, if a congestion information cell is erroneously scrapped to interrupt the feedback operation, the ACR calculated in the terminal does not coincide with the ACR calculated in the cell rate supervising unit. Therefore, the policing operation cannot be carried out normally. As a result, accessible cells may be scrapped or transmitted with special tags, or unaccessible cells may be transmitted through the cell rate supervising unit. The former makes a user terminal disadvantageous. The latter not only makes the user terminal disadvantageous, but also reduces the link utilization of the network. Although this abnormal state may soon disappear in an explicit rate (ER) mode, this abnormal state may not disappear for long time in a binary mode. This will be explained later in detail.
SUMMARY OF THE INVENTION
It is an object of the present invention to rapidly change an abnormal state caused by a difference in ACR between a user terminal and a cell rate supervising unit to a normal state in an ATM communication system.
According to the present invention, in a cell rate supervising system for supervising a rate of cells flowing in a certain direction, a binary mode congestion feedback loop terminating unit terminates a first congestion feedback loop on a downstream side of that direction. The first congestion feedback loop receives a first congestion management cell from the downstream side and turns the first congestion management cell in a binary mode to the downstream side. Also, an ER mode congestion feedback loop terminating unit is provided on an upstream side of the binary mode congestion feedback loop terminating unit, and terminates a second congestion loop on an upstream side of the direction. The second congestion feedback loop receives a second congestion management cell from the upstream side and turns the second congestion management cell in an ER mode to the upstream side. Further, a DGCRA unit is provided on an upstream side of the ER mode congestion feedback loop terminating unit, and monitors the rate of cells in accordance with the second congestion management cell.
Thus, the congestion feedback loops are shorter than those of the prior art. Therefore, congestion feedback information can be rapidly formed.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be more clearly understood form the description as set forth below, with reference to the accompanying drawings, wherein:
FIG. 1 is a block circuit diagram illustrating a prior art ATM communication sytem;
FIG. 2 is a format of the RM cells of FIG. 1;
FIG. 3 is a detailed block cricuit diagram of the user terminal of FIG. 1;
FIG. 4 is a flowchart showing the operation of the ACR calculating circuit of FIG. 3;
FIG. 5 is a detailed block circuit diagram of the DGCRA unit of FIG. 1;
FIG. 6 is a block circuit diagram illustrating a first embodiment of the ATM communication system according to the present invention;
FIG. 7 is a block circuit diagram illustrating a second embodiment of the ATM communication system according to the present invention;
FIG. 8 is a graph showing the ER value of the ER calculating circuit of FIG. 7; and
FIGS. 9 and 10 are block circuit diagrams illustrating modifications of the system of FIG. 7.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Before the description of the preferred embodiments, prior art ATM communication systems will be explained with reference to FIGS. 1, 2, 3, 4 and 5 (see: The ATM Forum Technical Committee, "Traffic Management Specification, Version 4.0", pp. 43-48, 68-71, 92-97, March 1996).
In FIG. 1, which illustrates a prior art ATM communication system, reference numerals 1 and 2 designate user terminals or end-systems (ES), and 3 designates an ATM switching unit (or cross-connect unit). Also, a DGCRA unit 4 is provided between the user terminal 1 and the ATM switching unit 3. When cells are transmitted from the user terminal 1 to the user terminal 2, a line L1 is a forward direction line and a line L2 is a backward direction line.
Note that FIG. 1 shows a one-directional transmission, however, a bi-directional transmission is also possible. Also, when cells are transmitted from the user terminal 2 to the user terminal 1, the line L2 is a forward direction line and the line L1 is a backward direction line. Also, another DGCRA unit as a cell rate supervising unit is provided between the user terminal 2 and the ATM switching unit 3; however, this DGCRA unit is omitted from FIG. 1 to simplify the description.
When the user terminal 1 as a source transmits data cells D via the line L1 to the user terminal 2, the cell rate of the data cells D is not larger than an ACR. Also, a resource management (RM) cell, i.e., a forward-direction RM (FRM) is transmitted per a definite number of data cells D such as 32 data cells D.
On the other hand, the user terminal 2 as a destination extracts the FRM cells and feeds back these cells as backward-direction RM (BRM) cells to the line L2. In this case, the user terminal 2 can write congestion information into the BRM cells. Further, the ATM switching unit 3 writes congestion information into the FRM cells or the BRM cells.
When the user terminal 1 as a source receives the BRM cells, the user terminal 1 changes the ACR or calculates an ACR in accordance with the congestion information stored in each of the BRM cells.
In FIG. 2, which illustrates a format of one of the RM cells of FIG. 1, this format is common for the FRM cells and the BRM cells (see p.43 of the above-mentioned document). Particularly, a direction (DIR) bit indicates an FRM cell (="1") or a BRM cell (="1"). The DIR bit is changed when turned around by at a destination which is the user terminal 2, for example. Also, a congestion indication (CI) bit, a no increase (NI) bit and an explicit cell rate (ER) field are provided for feedback congestion information.
The CI bit indicates that there is congestion in the ATM switching unit 3 or the user terminal 2 serving as a destination. That is, if there is congestion, the ATM switching unit 3 or the user terminal 2 serving as a destination sets "1"in the CI bit. Otherwise, "0" is set in the CI bit.
The NI bit is used to prevent a source from increasing its ACR. That is, if there is congestion, the ATM switching unit 3 or the user terminal 2 serving as a destination sets "1" in the NI bit. Otherwise, "0" is set in the NI bit.
The ER field is used to limit the ACR of the user terminal 1 serving as a source to a special value. The ER field is initially set to a PCR.
An ACR is calculated in accordance with the feedback congestion information CI, NI and ER in the user terminal 1 serving as a source.
In FIG. 3, which is a detailed block circuit diagram of the user terminal 1, reference numeral 11 designates a cell assemblying circuit for receiving transmitting data to assemble data cells D. The data cells D are supplied to an RM cell insertion circuit 12, so that the data cells D are merged with ERM cells. The FRM cells are formed by an FRM cell forming circuit 13. In this case, CI, NI and ER are definite values. The data cells D associated with the FRM cells are stored in a cell buffer 14. The cells stored in the cell buffer 14 are then transimitted to the line L1 at a rate not larger than the ACR.
On the other hand, a cell buffer 15 receives BRM cells from the line L2 and stores them. The BRM cells are deassembled at a cell disassembling circuit 16. Then, the BRM cells are extracted by a BRM extraction circuit 17.
An ACR calculating circuit 18 is provided between the BRM extraction circuit 17 and the cell buffer 14. That is, the ACR calculating circuit 18 calculates an ACR in accordance with feedback congestion information CI, NI and ER extracted by the BRM cell extraction circuit 17, and supplies the calculated ACR to the cell buffer 14. This will be explained later in detail with reference to FIG. 4.
In FIG. 3, note that an FRM cell extraction circuit 19 and an FRM cell forming circuit 20 are operated when the user terminal 1 serves as a destination. In this case, the FRM forming circuit 20 extracts FRM cells, and writes predetermined bits into the FRM cells to pass the received data cells as well as the written FRM cells. Simultaneously, the FRM cell extraction circuit 19 writes "1" into the DIR bit of the extracted FRM cells and supplies them to the BRM cell forming circuit 20.
The operation of the ACR calculating circuit 18 of FIG. 3 is explained below with reference to FIG. 4 (see Source Behavior of pp. 45 and 46 of the above-mentioned document).
First, at step 401, it is determined whether or not the CI bit is "1", and also, at step 402, it is determined whether or not the NI bit is "0". As a result, if CI="1", the control proceeds to step 403 to 405. Also, if CI=NI="0", the control proceeds to steps 406 to 408. Further, if CI="0" and NI="1", the control proceeds directly to steps 409 and 410.
At step 403, the current ACR is decreased by
ACR←ACR-ACR·RDF
where RDF is a constant. Then, at steps 404 and 405, the ACR is guarded by a minimum value, i.e., MCR.
At step 406, the current ACR is increased by
ACR←ACR+ACR·RDF
Then, at steps 407 and 408, the ACR is guarded by a maximum value, i.e., PCR.
At step 409, it is determined whether or not ACR is larger than ER. Only if ACR>ER, does the control proceed to step 410 which causes ACR to be ER. That is, a minimum value of ACR and ER is selected as a new ACR.
At steps 411 and 412, the current ACR is again guarded by a minimum value, i.e., MCR. Thus, the ER value is prevented from being smaller than MCR.
Finally, at step 413, the ACR is outputted to the cell buffer 14 of FIG. 3.
Note that the flowchart as shown in FIG. 4 can be constructed by hardware.
The ACR service is divided into a binary mode and an ER mode. In the binary mode, the ACR is subject to the CI bit and the NI bit. For example, if PCR is set in ER, the ACR is changed at steps 403 to 408 in accordance with the CI bit and the NI bit, and also, the ACR is unchanged by steps 409 and 410. On the other hand, in the ER mode, the ACR is subjected to the ER field. In this case, CI="0" and NI="1". Note that the flowchart of FIG. 4 can respond to both the binary mode and the ER mode.
In FIG. 5, which is a detailed block circuit diagram of the DGCRA unit 4 of FIG. 1, a cell disassembling circuit 41, a BRM cell extration circuit 42 and an ACR calculating circuit 43 having the same configurations as the cell disassembling circuit 16, the BRM cell extraction circuit 17 and the ACR calculating circuit 18, respectively, of FIG. 3, are provided. Also, a PACR calculating circuit 44 calculates a policing ACR (PACR) in accordance with the ACR calculated in the ACR calculating circuit 43. The PACR is obtained by delaying the ACR by a transmission delay time t of a BRM cell X outgoing from the DGCRA unit 4 to the user terminal 1. Such a delay time t depends on the distance between the DGCRA unit 4 and the user terminal 1, the configuration of the user terminal 1, hardware such as a private branch exchange (PBX) between the DGCRA unit 4 and the user terminal 1, and the like. The algorithm of the PACR calculating circuit 44 is discussed on page 92 to 96 of the above-mentioned document.
On the other hand, a cell rate calculating circuit 45 calculates a cell rate CR of cells propagating in the forward direction of the line L1. The cell rate CR is supplied to a rate comparing circuit 46, so that the cell rate CR is compared with PACR. As a result, if CR≦PACR, a cell processing circuit 47 passes cells therethrough. On the contrary, if CR>PACR, the processing circuit 47 scraps cells or passes the cells with special tags.
Here, the ACR calculated by the user terminal 1 is denoted by ACRU and the ACR calculated by the DGCRA unit 4 is denoted by ACRD.
If the RM cell X normally arrives at the user terminal 1, then
ACRD=ACRU.
However, if the RM cell X is scrapped in the line L2 between the DGCRA unit 4 and the user terminal 1, the PBX or the like, the ACRU of the ACR calculating circuit 18 does not coincide with the ACRD of the ACR calculating circuit 43, i.e.,
ACDR≠ACRU
This state continues for a long time in the binary mode.
For example, if the RM cell X includes CI="1", the ACRD is decreased, while the ACRU is not changed. Therefore,
ACRD<ACRU
In this case, accessible cells may be scrapped or transmitted with special tags, so that the user terminal 1 is more disadvantageous than the ATM switching unit 3. Note that this state continues until both ACRD and ACR reach MCR.
On the other hand, if the RM cell X includes CI ="0" and NI="0", the ACRD is increased, while the ACRU is not changed. Therefore,
ACRD>ACRU
In this case, in spite of having a right to use a bandwidth to the ACRD, the user terminal 1 cannot increase its cell rate up to ACRU. As a result, the user terminal 1 is disadvantageous, and the link utilization of the network is reduced. Note that this state continues until both ACRD and ACRU reach PCR.
In FIG. 6, which illustrates a first embodiment of the present invention, two virtual terminals 5 and 6 are provided between the DGCRA unit 4 and the ATM switching unit 3 of FIG. 1, and cell buffers 7 and 8 are provided between the virtual terminals 5 and 6. The virtual terminals 5 and 6 and the cell buffers 7 and 8 have the same configuration; however, since it is assumed that data cells stream from the user terminal 1 to the ATM switching unit 3, only the related components are illustrated for simplifying the description.
The virtual terminal 5 terminates a congestion feedback loop for the DGCRA unit 4 and the user terminal 1, as indicated by LP1. In other words, RM cells from the DGCRA unit 4 are turned around by the virtual terminal 5 using the ER mode, although data cells pass therethrough.
The virtual terminal 6 terminates a congestion feedback loop for the ATM switching unit 3, as indicated by LP2. In other words, RM cells from the ATM switching unit 3 are turned around by the virtual terminal 6 using the binary mode, although data cells pass therethrough.
The virtual terminal 5 includes a cell buffer 51 for storing cells in the forward direction data stream, an RM cell extraction circuit 52 for extracting FRM cells from the cells transited from the cell buffer 51 to the cell buffer 7, an RM cell forming circuit 53a for forming BRM cells by receiving ACRs from the virtual terminal 5 and writing them into the extracted FRM cells, and an RM cell insertion circuit 54 for inserting the BRM cells in the backward direction data stream from the cell buffer 8 to a cell buffer 55.
The virtual terminal 6 includes a cell buffer 61 for storing cells in the backward direction data stream, an RM cell extraction circuit 62 for extracting BRM cells from the cells from the cell buffer 61 to the cell buffer 8, an RM cell forming circuit 63b for forming FRM cells, and an RM cell insertion circuit 64 for inserting the FRM cells in the forward direction data stream from the cell buffer 7 to a cell buffer 65. Also, an ACR calculating circuit 66 is provided between the RM cell extraction circuit 62 and the cell buffer 65, and is further connected to the RM cell forming circuit 53a of the virtual terminal 5. That is, the ACR calculating circuit 62 calculates an ACR in accordance with the CI bit, the NI bit and the ER field of the extracted cell by the RM cell extraction circuit 62, thus policing the cells in the forward direction data stream at the cell buffer 65.
The operation of the virtual terminal 6 is explained next.
First, the cell buffer 61 receives cells flowing in the backward direction to transmit the cells to the RM cell extraction circuit 62. As a result, the RM cell extraction circuit 62 extracts RM cells from the received cells, and writes empty data thereinto. Then, the received cells as well as the empty RM cells are transmitted to the cell buffer 8.
Simultaneously, the RM cell extraction circuit 62 transmits only BRM cells of the extracted RM cells to the ACR calculating circuit 66. As a result, the ACR calculating circuit 66 calculates an ACR in accordance with the CI bit, the NI bit and the ER field of each BRM cell. The ACR is supplied to the cell buffer 65 to carry out a policing operation, and is supplied to the virtual terminal 5. Note that the ACR calculated by the ACR calculating circuit 66 is a binary mode.
On the other hand, the RM cell insertion circuit 64 inserts FRM cells or BRM cells into cells flowing from the cell buffer 7 to the cell buffer 65. In this case, the FRM cells are formed in the RM cell forming circuit 63b, and the BRM cells are formed in an RM cell forming circuit (not shown) corresponding to the RM cell forming circuit 53a.
The operation of the virtual terminal 5 is explained next.
First, the cell buffer 51 receives cells flowing in the forward direction to transmit the cells to the RM cell extraction circuit 52. As a result, the RM cell extraction circuit 52 extracts RM cells from the received cells, and writes empty data thereinto. Then, the received cells as well as the empty RM cells are transmitted to the cell buffer 7.
Simultaneously, the RM cell extraction circuit 52 transmits only ERM cells of the extracted RM cells to the RM cell forming circuit 53a. As a result, the RM cell forming circuit 53a changes the DIR bit of each of the ERM cells, so that the FRM cells are changed into BRM cells. In addition, the RM cell forming circuit 53a writes the ACR of the ACR calculating circuit 66 into the ER field of each of the BRM cells. Note that the ACR written into each of the BRM cells is an ER mode.
On the other hand, the RM cell insertion circuit 54 inserts FRM cells or BRM cells into cells flowing from the cell buffer 8 to the cell buffer 55. In this case, the BRM cells are formed in the RM cell forming circuit 53a, and the FRM cells are formed in a RM cell forming circuit (not shown) corresponding to the RM cell forming circuit 63b.
Thus, congestion information regarding the ATM switching unit 3 is written by the virtual terminal 5 into the RM cells turned around by the virtual terminal 5. In this case, however, the DGCRA unit 4 and the user terminal 1 receive the congestion information as if the congestion information were formed in the ATM switching unit 3.
As a result, the DGCRA unit 4 performs a policing operation using the congestion information turned around by the virtual terminal 5 upon the cells flowing in the forward direction.
Thus, since the next congestion information is formed in the virtual terminal 5, not in the ATM switching unit 3, even if RM cells are erroneously scrapped between the DGCRA unit 4 and the user terminal 1, the ACR calculated in the DGCRA unit 4 is immediately brought close to the ACR calculated in the user terminal 1. Thus, an abnormal state can immediately be made to disappear.
Also, since the virtual terminal 5 writes ACRs in an ER mode into BRM cells, it is unnecessary in the DGCRA unit 4 to provide means for converting congestion information in a binary mode into congestion information in an ER mode.
In FIG. 7, which illustrates a second embodiment of the present invention, an ER calculating circuit 56 is provided between the cell buffer 7 and the RM cell forming circuit 53a of FIG. 6. Instead of this, the ACR calculating circuit 66 is not connected to the RM cell forming circuit 53a. That is, the ER calculating circuit 56 calculates an ER in accordance with a cell queue QL in the cell buffer 7 as shown in FIG. 8.
As shown in FIG. 8, if QL≧TH where TH is a maximum value of the cell queue QL, then,
ER=MCR.
Also, if QL≦TL where TL is a minimum value of the cell queue QL, then,
ER=PCR.
Further, if TL<QL<TH, then,
ER=PCR
-(PCR-MCR)(QL-TL)/(TH-TL)
As a result, the RM cell forming circuit 53a changes the DIR bit of each of the FRM cells, so that the FRM cells are changed into BRM cells. In addition, the RM cell forming circuit 53a writes the ER of the ER calculating circuit 56 into the ER field of each of the BRM cells.
The cell queue QL of the cell buffer 7 is changed in accordance with the cell rate of the virtual terminal 6 in the backward direction. Therefore, the cell queue QL is changed in accordance with the congestion state of the ATM switching unit 3.
Thus, even in the second embodiment, congestion information regarding the ATM switching unit 3 is written by the virtual terminal 5 into the RM cells turned around by the virtual terminal 5. In this case, however, the DGCRA unit 4 and the user terminal 1 receive the congestion information as if the congestion information were formed in the ATM switching unit 3.
As a result, the DGCRA unit 4 performs a policing operation using the congestion information turned around by the virtual terminal 5 upon the cells flowing in the forward direction.
Thus, since the next congestion information is formed in the virtual terminal 5, not in the ATM switching unit 3, even if RM cells are erroneously scrapped between the DGCRA unit 4 and the user terminal 1, the ACR calculated in the DGCRA unit 4 is immediately brought close to the ACR calculated in the user terminal 1. Thus, an abnormal state can immediately be made to disappear.
Also, since the virtual terminal 5 writes ERs into BRM cells, it is unnecessary in the DGCRA unit 4 to provide means for converting congestion information in a binary mode into congestion information in an ER mode.
In FIG. 9, which is a modification of the system of FIG. 7, the ER calculating circuit 56 is connected to the cell buffer 65 of the virtual terminal 5, not the cell buffer 7. Therefore, the ER calculating circuit 56 calculates an ER in accordance with a cell queue in the cell buffer 65.
In FIG. 10, which also is a modification of the system of FIG. 7, the ER calculating circuit 56 is connected to the cell buffer 61 of the virtual terminal 5, not the cell buffer 7. Therefore, the ER calculating circuit 56 calculates an ER in accordance with in a cell queue in the cell buffer 61.
Note that the ER calculating circuit 56 can calculate an ER in accordance with two or three cell queues in the cell buffers 7, 65 and 61.
As explained hereinabove, according to the present invention, an abnormal state caused by a difference in ACR between a user terminal and a cell rate supervising unit can be rapidly changed to a normal state. | In a cell rate supervising system for supervising a rate of cells flowing in a certain direction, a binary mode congestion feedback loop terminating unit terminates a first congestion feedback loop on a downstream side of that direction. The first congestion feedback loop receives a first congestion management cell from the downstream side and turns it in a binary mode to the downstream side. Also, an explicit rate (ER) mode congestion feedback loop terminating unit is provided on an upstream side of the binary mode congestion feedback loop terminating unit, and terminates a second congestion loop on an upstream side of the direction. The second congestion feedback loop receives a second congestion management cell from the upstream side and turns it in an ER mode to the upstream side. Further, a dynamic generic cell rate algorithm unit is provided on an upstream side of the ER mode congestion feedback loop terminating unit, and monitors the rate of cells in accordance with the second congestion management cell. | 7 |
FIELD OF THE INVENTION
[0001] This invention relates to the design and construction of a novel, scope and corresponding ring mounts for the improved accuracy and stability of scopes.
BACKGROUND OF THE INVENTION
[0002] Scopes, particularly those used for hunting, are well known in the prior art. Scopes are generally mounted to rifles or similar weapons and are used to assist hunters in aiming at desired targets. The prior art traditionally discloses the use of an externally smooth, cylindrical scope that is mounted to a rifle through the use of scope rings, which are traditionally smooth and cylindrical as well. However, there are several disadvantages attributable to using a scope and mounting device that are cylindrical.
[0003] For example, a traditional smooth and cylindrical scope with a cylindrical mounting device is very difficult to align perfectly straight up and down so that the scope's reticle is not canted. When a scope's reticle is canted, the accuracy of the reticle's aim will be off thus causing a hunter to miss or merely wound a desired target. Typically, a canted reticle is caused by human error that occurs when a user must precisely align the scope with a separate mounting device before securing the scope to a rifle or similar weapon. A scope formed with indentations and a corresponding scope ring with a projecting key that mates with the scope's indentations, or vis versa, ensures that the scope's reticle will always align accurately. The reticle will always align accurately because the indentations formed on the scope, as opposed to being formed on a separate mount that is later affixed to the scope as known in the prior art, and the projecting key on the scope ring act as a guide for aligning the scope and ring; thereby eliminating the step where most errors in alignment and accuracy occur (i.e. when a user attempts to align a scope with a separate mounting device). Additionally, a non-cylindrical scope, preferably a scope formed with octagonal sides and a corresponding octagonal mount will also act as a guide for aligning the scope and mount. The octagonal scope can also be used in connection with the indentation and key features described above to further assist the user with aligning the scope correctly.
[0004] Another disadvantage of traditional smooth, cylindrical scopes with cylindrical mounting devices is what is commonly referred to as “scope creep.” Scope creep occurs when the scope shifts in the mounting device as a result of the recoil force that occurs when a rifle or similar weapon is fired. Scope creep causes the scope's reticle to misalign, which compromises the scope's accuracy and performance. Scope creep may occur even in cases where the scope and separate mounting device were initially aligned perfectly by the user. In some instances, scope creep may also pose a danger to the user by causing the scope to shear off from the mounting device. A scope formed with a plurality of indentations on the top and/or bottom of the front and/or back of the stock, which mate with the projecting key on the corresponding scope ring will solve this problem because it will secure the scope and ring and prevent it from shifting due to recoil when a weapon is discharged.
[0005] Clearly there is a need for a scope formed with indentations and a corresponding scope ring with a projecting key to ensure that the scope's reticle is accurately aligned and not canted and to further prevent scope creep and the problems associated with recoil when a rifle is fired. There is also a need for scopes formed of various non-cylindrical shapes, preferably octagonal, and corresponding mounts to further address the disadvantages associated with the prior art.
SUMMARY OF THE INVENTION
[0006] The inventive structure presents a number of advantages over the prior art. First, the invention is simple to form. The scope is formed with a plurality of indentations on the top and/or bottom of the front and/or back portion of the scope. The inventive structure further comprises at least two corresponding scope rings. The back scope ring, front scope ring, or both further comprises a projecting key that mates with the plurality of indentations on the scope stock. The indentations and corresponding key may be any shape, preferably circles or crosses.
[0007] Additionally, forming the stocks and corresponding mounts in various shapes, preferably the octagonal stock is advantageous because the scope's wall thickness will be very similar to traditional, cylindrical scopes and there will not be added weight from material. It is well known that additional weight during recoil becomes inertia (i.e. resistance to change), which means that when a rifle is fired the more weight in the scope the greater the strain on the mount and the securing hardware and the more force exerted against the grip of the scope rings on the scope tube. The additional weight has several other disadvantages, such as causing the scope's reticle to misalign upon recoil, causing damage to the scope's innards due to shifting caused by the recoil force, and causing the scope to shear off the mount and injure the user. The additional weight also makes the rifle heavier for a user to lift and carry.
[0008] The plurality or indentations and corresponding key as well as the octagonal shape is also advantageous because it ensures that the scope is aligned perfectly straight up and down so that the reticle is not canted. In the preferred embodiment, the indentations or the point of the octagonal shape will be formed in the dead center of the scope. Thus, when the shooter connects the point on the scope with the corresponding rings the reticle will align perfectly each time.
[0009] Another advantage of the inventive structure is that because the octagonal rings match the shape of the octagonal stock a better surface engagement results in the inventive structure than with traditional cylindrical scopes and rings. Further, the plurality of indentations around the entire stock or on the upper and/or lower portion of the stock will accept the retaining detail on the back and/or front scope rings and prevent the scope from moving in either direction thereby eliminating problems associated with scope creep. The plurality of indentations is further advantageous because the indentations allow the shooter to adjust for eye relief.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a view of the scope and corresponding scope rings according to the embodiments described herein.
[0011] FIG. 2 is a view of the scope and corresponding scope rings according to the embodiments described herein.
[0012] FIG. 3 is a view of the octagonal scope and corresponding octagonal scope rings according to the embodiments described herein.
DETAILED DESCRIPTION OF THE INVENTION
[0013] Shown in FIG. 1 is a scope ( 1 ) and its corresponding front ring ( 2 ) and back ring ( 3 ). The scope may be formed of octagonal or cylindrical tube stock and is formed with anindentation or indentations ( 4 ) as shown in FIG. 1 . The indentations may be any shape but preferably circular or in the shape of crosses to aid in restricting movement in all axis. The indentations ( 4 ) mate with a corresponding scope ring ( 2 ) or ( 3 ), which has a complementary projecting key ( 5 ) located on its inner surface, as shown in FIG. 2 , in the same shape as the plurality of indentations ( 4 ) for purposes of mating the key with the indentation. The indentations may be formed on any combination of the upper and lower portion of the front or back portion of the scope stock. The projecting key may be formed on the front ( 2 ) or back ( 3 ) scope ring or both of the corresponding scope rings, and located on either the top half of either ring or the bottom half of either ring or both halves. Furthermore, the indentations may be formed on the inside of the scope rings ( 2 ) and ( 3 ) with the corresponding key formed on the scope ring.
[0014] Also Shown in FIG. 1 is an octagonal scope ( 1 ) and its corresponding octagonal front ring ( 2 ) and back ring ( 3 ). In the preferred embodiment, the octagonal front ring ( 2 ) mates with corresponding octagonal sides of the scope ( 1 ). The octagonal back ring ( 3 ) mates with the corresponding octagonal sides of the scope ( 1 ) and further mates with the plurality of grooves ( 4 ) on the scope ( 1 ). The octagonal back ring ( 3 ) also comprises retaining detail ( 5 ), as shown in FIG. 2 , which assists in mating with the plurality of grooves ( 4 ) on the scope ( 1 ) and prevents scope creep. The plurality of grooves ( 4 ) on the scope ( 1 ) also allows the shooter to adjust for eye relief while still providing the advantages against scope creep. It should be understood that the use of octagonal scope tube stock with corresponding octagonal scope rings is an alternative embodiment of the invention to reduce canting of the scope when mounted on a rifle.
[0015] Referring now to FIG. 3 , shown is another preferred embodiment of the disclosed invention. In this embodiment, the plurality of grooves ( 4 ) on the scope ( 1 ) is only on the bottom of the scope ( 1 ) and a pin ( 6 ) is used to prevent the scope from moving in the mounting device and causing scope creep. | A telescopic scope and ring mounts incorporating a novel feature for locking the ring mounts to the scope to prevent canting and scope drift for secure and easy mounting on a gun. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a refrigerator, and more particularly to a defrost-water vaporizer for a refrigerator capable of rapidly vaporizing defrost-water.
2. Prior Arts
FIG. 1 is a schematic view of a conventional refrigerator.
As shown in FIG. 1, a general household refrigerator includes a cabinet 1, a freezing compartment 2, a storage compartment 3 and vegetable compartment 4. The temperature in storage compartment 3 is higher than that in freezing compartment 2 and lower than that in vegetable compartment 4.
Reference numeral 5 indicates a vaporizer installed at the rear of freezing compartment 2 and reference numeral 6 indicates a fan for supplying freezing compartment 2 and storage compartment 3 with cool air. Reference numeral 7 is a machine compartment installed at the lower bottom part of cabinet 1, a defrost-water vaporizer 8 for vaporizing defrost-water is provided within machine compartment 7.
Generally, cool air is generated in a refrigerator by absorbing surrounding heat while a liquid-state refrigerant compressed in a compressor (not shown) is being vaporized. Fan 6 circulates the cool air in freezing compartment 2 and storage compartment 3 and thereby air in freezing compartment 2 and storage compartment 3 is cooled. At this time, the temperature difference between the cool air in freezing compartment 2 and storage compartment 3 and the air in evaporator 5 creates defrost-water.
The defrost-water flows together to a water-vaporization tray (not shown) of vaporizer 8 installed at the lower part of machine compartment 7 through a defrost-water bucket of vaporizer 5 and a pipe (not shown).
Conventionally three kinds of vaporizers are used for a refrigerator. One is to spontaneously vaporize defrost-water by enlarging the area of the water-vaporization tray. The other is to vaporize defrost-water by means of the high temperature heat of refrigerant passing through a condenser pipe installed at the lower part of the water-vaporization tray. And the third vaporizer vaporizes defrost-water by way of the high temperature heat of a compressor installed at the lower part of the water-vaporization tray.
At this time, the first vaporizer lacks the vaporizing efficiency. If the humidity is high outside or if much defrost-water is generated, the defrost-water overflows since it is not fully vaporized.
The second vaporizer takes advantage of the high heat of refrigerant passing through the condenser pipe which is installed at the lower part of the water-vaporization tray to connect the compressor with the vaporizer. The second vaporizer has greater efficiency in vaporizing the defrost-water than in the first vaporizer. However, since the condenser pipe is additionally installed at the lower part of the water-vaporization tray, the assembling process of a product is lengthened so that additional cost is involved.
According to the last vaporizer in which the water-vaporization tray is installed at the upper part of the compressor, space inside the machine compartment is available because the size of the water-vaporization tray is reduced, however, it is still a problem to reduce the efficiency of vaporizing defrost-water.
SUMMARY OF THE INVENTION
Therefore, it is an object of the present invention to provide a vaporizer for a refrigerator capable of vaporizing defrost-water in a short time.
Further, another object of the present invention is to provide a vaporizer for a refrigerator capable of making the most efficient use of the space in a machine compartment and storage compartment.
In order to achieve the above objects, a vaporizer for a refrigerator is preferably embodied according to the present invention. The vaporizer comprises a water-vaporization tray integrally formed with a pair of brackets, the brackets being set up on the opposite sides of the tray in an upper direction, and for collecting and containing defrost-water; a defrost-water absorption means disposed between and supported by the pair of brackets and for absorbing and moving the defrost-water; a blow-off means for generating blowing air to send it to the defrost-water absorption means by way of rotating force obtained from an alternating power source supplied from outside; and a power transmission means for transmitting the rotating force to the defrost-water absorption means to thereby move the defrost-water.
More particularly, a blower rotates according to a motor and a rotating shaft being rotated. At the same time, the rotating force of the motor and the rotating shaft is supplied to an upper roller and a lower roller of the defrost-water absorption means through the power transmission means and thereby the upper and the lower rollers are rotated. According to the rotation of the rollers, the defrost-water on the water-vaporization tray is suctioned into a vaporization belt and the suctioned defrost-water is vaporized by the blower. Therefore, it is possible to vaporize defrost-water quickly, and good vaporization efficiency is obtained.
BRIEF DESCRIPTION OF THE DRAWINGS
The objects and other advantages of the present invention will be apparently understood with reference to the accompanying drawings, in which:
FIG. 1 is a schematic view of a prior art refrigerator and
FIG. 2 is a detail view of a defrost-water vaporizer for a refrigerator according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Hereinafter, the preferred embodiment of the present invention will be described in greater detail by referring to the attached drawings.
FIG. 2 is a detail view of a defrost-water vaporizer for a refrigerator according to the present invention. As shown in FIG. 2, the defrost-water vaporizer comprises a water-vaporization tray 10, a blower 20, a driving force transmission portion 30, and defrost-water absorption portion 40. Water-vaporization tray 10 includes a box-shaped water tray part 14 and a pair of brackets 11 and 12 integrally formed with both opposite sides of water tray part 14. A pair of brackets 11 and 12 are formed in an upper direction from water tray part 14 and disposed at the rear side of water tray part 14. The defrost-water is concentrated at water tray part 14 of water-vaporization tray 10 through a pipe 13.
Blower 20 is installed at the front part of water-vaporization tray 10. Blower 20 generates rotating force from a power source outside and at the same time causes blowing air. Blower 20 includes a motor 21, a rotating shaft 22 and a fan 23. Motor 21 creates rotating force by receipt of the power source from outside. The generated rotating force is transmitted to rotating shaft 22 to thereby rotate rotating shaft 22. According to the rotation of rotating shaft 22, fan 23 causes blowing air while being rotated. Fan 23 is axially connected with rotating shaft 22 and makes a rotation as rotating shaft 22 rotates. Motor 21 is provided at the front part of water-vaporization tray 10. Rotating shaft 22 connected with motor 21 is installed in parallel with the bottom of water tray part 14. Rotating shaft 22 passing through motor 21 is projected in both forward and backward directions of motor 21.
Driving force transmission portion 30 includes a driving pulley 31 for transmitting rotating force of rotating shaft 22, a driven pulley 33 for receiving the rotating force transmitted from rotating shaft 22, a pulley belt 32 for connecting driving pulley 31 and driven pulley 33 to transmit the rotating force of driving pulley 31 to driven pulley 33, a gear shaft 34 axially connected with driven pulley 33, a driving gear 35 formed at the end of gear shaft 34 and for rotating according to the rotation of driven pulley 33, and a driven gear 36 meshed with driving gear 35 and for reversing the rotating direction of driving gear 35. At this time, since the diameter of driven pulley 33 is larger than that of driving pulley 31, the rotating speed of driven pulley 33 is reduced. A pair of shaft supports 37 are provided to support gear shaft 34.
Driven gear 36 is meshed with driving gear 35 at a right angle to each other, and a helical gear or a bevel gear is normally used for driven gear 36.
Between a pair of brackets 11 and 12, defrost-water absorption portion 40 for rotating while absorbing defrost-water is connected to the shaft of driven gear 36.
Defrost-water absorption portion 40 moves the defrost-water contained in water tray part 14 while rotating according to the shaft of driven gear 36 being rotated.
Specifically, between the upper parts of a pair of brackets 11 and 12, upper roller 42 is provided with an upper roller shaft 41 being installed at the center thereof. Both ends of upper roller 41 are rotatably connected to the pair of brackets 11 and 12 respectively.
Lower roller 44 is provided below upper roller 42 with a certain spacing. At the center of lower roller 44 a lower roller shaft 46 is provided. Both ends of lower roller 46 are rotatably connected with each of brackets 11 and 12. A part of lower roller 44 is submerged in the defrost-water contained in water tray part 14.
Each of the ends of lower roller shaft 43 is installed protrudingly in an outer direction from each of brackets 11 and 12. At one end of lower roller shaft 43 driven gear 36 is fixed. Thus, the rotation of driven gear 36 makes lower roller 44 rotating.
Around upper roller 42 and lower roller 44, a vaporization belt 45 is rolled. Accordingly, as lower roller 44 rotates, the rotation is transmitted to upper roller 42 by means of vaporization belt 45. Thus, when upper roller 42 is rotated according to the rotation of lower roller 44, vaporization belt 45 submerged in the water is moved upward. As vaporization belt 45 goes through lower roller 44, vaporization belt 45 absorbs the defrost-water in water-vaporization tray 10. The absorbed defrost-water moves from lower roller 44 to upper roller 42 with vaporization belt 45. At this time, vaporization belt 45 is formed broadly to the extent that lower roller 44 and upper roller 45 are fully covered.
According to the embodiment of the present invention described in the foregoing, the defrost-water vaporizer operates as follows.
From an inputted alternating power source, motor 21 is operated. The rotation of motor 21 makes driving pulley 31 of driving force transmission portion 30 rotate through rotating shaft 22.
The rotation of driving pulley 31 is applied to driven pulley 33 through pulley belt 32 and driven pulley 33 is rotated. The rotating speed of driven pulley 33 is reduced more than that of driving pulley 31 since driving pulley 31 has a smaller diameter than driven pulley 33.
By the rotation of driven pulley 33 being applied to driving gear 35 via gear shaft 34, driving gear 35 is rotated. The rotation of driving gear 35 applied to driven gear 36 rotates driven gear 36.
At this time, since driving gear 35 is meshed with driven gear 36 at a right angle, their rotations are also made perpendicularly.
Lower roller 44 is rotated by the rotation of driven gear 36 being applied to lower roller 44 through lower roller shaft 46. The rotation of lower roller 44 rotates upper roller 42 through vaporization belt 45. Vaporization belt 45 is rotated according to the rotation of lower roller 44 and upper roller 42.
As described in the foregoing, vaporization belt 45 revolves being submerged into defrost-water (shown as a wave form in FIG. 2). When vaporization belt 45 is submerged into the defrost-water, it absorbs defrost-water. Vaporization belt 45 that has absorbed defrost-water is moved upward from the defrost-water in water-vaporization tray 10.
Meanwhile, the rotation of motor 21 is transmitted to fan 23 through rotating shaft 22 to rotate fan 23. Fan 23 supplies blowing air toward vaporization belt 45 to thereby vaporize defrost-water absorbed by vaporization belt 45.
In the defrost-water vaporizer according to the above embodiment of the present invention, the defrost-water absorbed n vaporization belt 45 is vaporized by means of blower 20, thus the vaporization is performed in a very short time. Also, since the size of water-vaporization tray can be minimized, it is possible to obtain a smaller machine compartment and a comparatively larger freezing and storage compartments in a refrigerator.
The present invention was described by referring to an embodiment so far, however, it is possible to make modifications and changes of the present invention without diverging from the spirit of the invention. For example, natural blowing air may be used instead of the blower of the embodiment. | Disclosed is a defrost-water vaporizer for a refrigerator capable of vaporizing defrost-water in a short time. The defrost-water vaporizer includes a defrost-water absorption portion disposed between a pair of brackets and for absorbing and transmitting the defrost-water and a blow-off portion for generating rotating force from electric power and sending blowing air to the defrost-water absorption portion. The absorbed defrost-water is rapidly vaporized by the blow-off portion, and accordingly the vaporization efficiency is enhanced. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a method for drilling holes in soil or rock, especially for producing prestressed ground anchorage, and drilling equipment for carrying out said method.
2. Description of the Prior Art
Drilling equipment for producing holes for prestressed ground anchorage in soil or rock is known. Such equipment has a crawler truck with a carriage mount connected to articulated arms in such a way that it can be pivoted in all directions in space. A magazine for several lengths of pipe of the drill column is provided on such a drilling tool. The drive for the drill column with the drill bit can be raised and lowered on the carriage and mechanically transfers each length of pipe of the drill column from the magazine. After drilling the holes and before introducing the prestressed ground anchorage, the lengths of pipe of the drill column are returned to the magazine. A disadvantage of this system is that a borehole that can also hold casings to support the wall of the borehole cannot be drilled with such a drilling tool.
There is also a known drilling tool that has a single magazine in which the lengths of pipe of the drill column and the casing are arranged concentrically, one inside the other. A disadvantage of this system is that the lengths of pipe for the drill column and for the casing are unnecessarily long. This complicates the design of the drilling tool and therefore makes it unnecessarily expensive. The concentrically arranged drill column pipes and borehole casing pipes ar taken from the magazine together by a double-head drive for drilling and are transferred to the borehole. After drilling the borehoie, each length of pipe of the drill column must be transferred back to the magazine before the prestressed ground anchorage can be introduced. After the anchor has been introduced, each length of pipe of the drill column is removed from the magazine and then returned to the magazine once again with the length of casing in a concentric arrangement. Returning the length of pipe of the drill column and the casing back to the magazine is tedious and time-consuming, and furthermore, a special drive is necessary for the lengths of pipe.
Known prior art structures always start with designs using a single magazine (see, for example German Patent 24 35 535 C2, German Utility Patents 18 88 205, 87 14 952 U1, U.S. Pat. Nos. 4,897,009, 3,493,061, and Soviet Patent 785,460). This single magazine is used for lengths of pipe for the drill column, so the effectiveness of these known devices is not great.
The present invention solves the problem of providing an apparatus and drilling method for producing boreholes in soil or rock where said apparatus permits simpler handling of the lengths of pipe for the drill column and for the casing and also permits a simpler and therefore less expensive design for the drilling tool. An unnecessary structural height of the drilling tool thereby is avoided.
The invention also provides the advantage that the lengths of pipe of the drill column and the casing can be removed from a magazine separately from each other and in chronological succession and then can be returned to the magazine after drilling the hole for the prestressed ground anchorage. The operation of supplying the lengths of pipe of the drill column and the casing to the magazine is simplified by the present invention.
SUMMARY OF THE INVENTION
According to a preferred embodiment of this invention, separate magazines are used for the lengths of pipe of the drill column and the casing. These magazines are preferably stacked one above the other on the drilling tool. The lengths of pipe are removed one after the other from the magazines which are aligned in the working position and then are retracted back to their outer position. The pipe lengths are transferred by the drives in a concentric arrangement to the drilling position where they are connected to the end of the length of pipe for the drill column and the casing in the borehole. After drilling and casing the borehole for a predetermined length, the drill column is transferred length by length to the respective magazine. Then, the prestressed ground anchor is inserted into the borehole which still holds the casing. Next, the casing is removed length by length and transferred to the respective magazine. The magazines are pivoted into the operating position for this purpose and then are pivoted back to the starting position.
Other embodiments of the invention are described and claimed in the ensuing disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of a drilling tool according to the invention;
FIG. 2 is a partial frontal view of the tool shown in FIG. 1;
FIG. 3 is a sectional view taken along the line III--III in FIG. 2, in the direction indicated generally;
FIG. 4 is a schematic side view of a magazine with a locking device;
FIG. 5 is a top view of a roller guide;
FIG. 6 is an enlarged schematic view of the locking device in retracted position;
FIG. 7 is a view similar to FIG. 6, with the locking device in a forward position; and
FIG. 8 is a schematic side view of a working platform.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The drilling tool 1 may be provided with a track-laying vehicle 2 with hydraulically operated articulated arms 3, as known. A carriage 4 that can be raised and lowered and pivoted in all directions in space is mounted on the arms 3. Drive 6, which may be a duplex drive or double-head drive, is mounted on the carriage 4. Drive head 7 of drive 6 provides the rotary and/or percussive drive for the drill column with associated drill bit. Drive head 8 of drive 6 provides the rotary and/or percussive drive for the casing, optionally with the drill bit of the borehole when using a double-head drive, for example. With the duplex drive, the casing and drill column are rotated and/or vibrated at the same time.
The drill drive 6 is driven so it can be raised and lowered by a forward drive 9 positioned on carriage 4.
At the lower end 10 of carriage 4 there is a crushing, clamping and guide device 11 for securing, rotating and turning the connections, e.g., threaded connections of the lengths of pipe of the drill column and the casing. Bayonet connections may also be used.
According to the invention, magazines 12 for the lengths of pipe 13 of the drill column are arranged preferably on both sides next to the carriage. The magazines 12 are designed according to the revolver head principle. Thus, the magazines 12 can rotate about their central axis 14. They hold several lengths of pipe distributed around the periphery so that they can be removed freely toward the outside. Each magazine can be pivoted inward about pivot axis 15 from the outer storage position, as seen in FIG. 3, into a working position (not shown) by means of a pivot drive. In the working position, the drive head 7 can receive the aligned lengths of pipe 13 of the drill column. After receiving the lengths of pipe 13, the magazine is pivoted back into the storage position toward the outside.
Located beneath the magazines 12 for the lengths of pipe of the drill column there are magazines 16 for the lengths of pipe 17 of the casing for the borehole. The magazines 16 are arranged on both sides of the carriage 4 in the same way as magazines 12. The magazines 16 also are designed according to the revolver head principle. They can rotate about the middle axes 18. Magazines 16 hold several lengths of pipe of the casing for the borehole distributed around their periphery in such a way that can be removed freely toward the outside. Each magazine can be pivoted inward into a working position (not shown) from the outer storage position, as seen in FIG. 3, by means of a pivot drive. In the working position, a drive head 7 can hold the aligned respective length of pipe 13 of the drill column. After receiving a length of pipe 13 presented to it, the magazine pivots back to the storage position on the outside.
After a length of pipe 13 has been received by drive head 7, the drilling drive 6 is moved in reverse. Drive head 8 removes from magazine 16 which is in the operating position the aligned length of pipe 17 of the borehole casing which surrounds coaxially the length of pipe 13 of the drill column. Then the drive 6 moves downwardly after returning magazine 16 to its storage position. Lengths of pipe 13 and 17 are permanently connected in a known manner with the drill column or casing already in the borehole by using the crushing, clamping and guide device 11. Next, the rotary and/or percussive drive of drilling drive 6 is operated.
After finishing the borehole, first the drill column is dismantled length by length. The lengths of pipe 13 of the drill column are then moved to the height of magazines 12. Magazines 12 are then pivoted into position. Lengths of pipe 13 are then transferred to a fitting position in magazine 12. Next, the magazines are returned back to their storage position on the outside.
Thereafter, the prestressed ground anchor is installed in the borehole which still contains the casing. Then the casing is dismantled length by length. The lengths of pipe 17 of the casing are transferred to magazines 16 in a manner similar to that described above.
In order for the length of the carriage not to be too great and the drilling tool not to be too heavy, it is advisable to select a length of about 2 meters for lengths of pipe 13, 17.
Essentially, it is also possible to accommodate the lengths of pipe 13 for the drill column and the lengths of pipe 17 for the casing side by side in a single magazine. The magazines need not be provided on the drilling tool itself either. They can also be set up at nearby locations, e.g., other vehicles.
When magazine 13 is pivoted out of its storage position, as seen in FIG. 3, into the working position by rotating it about swivel axis 15, one length of pipe 13 is positioned coaxially beneath drive head 7. The drive head 7 must then be functionally connected to the proper length of pipe 13. For this purpose, the respective magazine 13 may have a locking device 20, as seen in FIG. 4, that is capable of holding the length of pipe 13 of the drill column which is in the working position in a secure manner so that it cannot twist as the drive head 7 is connected to the length of pipe 13, e.g., by means of a screw connection. The length of pipe 13 may have a thread 43 in the upper area onto which the drive head 7 is screwed.
As seen in FIGS. 4, 6 and 7, the locking device 20 consists of two elements 21 and 22, each of which has sliding inclines 24 and 25 that cooperate together. The first element 21 is provided with a key-shaped lock 23 beneath guide 27, so that the front area of the key-shaped lock is in a position to engage in a corresponding key-shaped surface 42 on the outer periphery of length of pipe 13. Below the key-shaped lock 23, the first element 21 of locking device 20 is designed so that it can slide by the outer circumference of a length of pipe 13 on both sides.
The second element 22 is attached to a carriage 44, which is arranged in the central area Z of the respective magazine 12 or 16 so that it is adjustable in height on the middle axis 14 or 18. The carriage 44 is connected to a piston-cylinder unit 26 that is supported in the central area Z of the respective magazine.
FIG. 6 shows locking device 20 in the retracted position. When the piston-cylinder unit 26 shown in FIG. 7 is operated, the carriage 44 is shifted upwardly on axis 14 so that the first element 21 is advanced over the second element 22 and the sliding surface 24 is advanced over the sliding surface 25 in the direction of the arrow to the right until the front side of the key-shaped lock 23 engages in the key surface 42 and thus secures length of pipe 13 which is in the operating position so that it cannot twist. Guide 27, which is securely connected to central area Z, serves here as a mating surface during the process of sliding the first element 21.
Then the drive head 7 can be lowered from above and connected to length of pipe 13 by means of thread 43 so that it cannot twist. After creating this connection, the piston-cylinder unit 26 is actuated again, so that the locking device 20 moves back out of the position illustrated in FIG. 7 into the position illustrated in FIG. 6. Length of pipe 13 is moved by means of drive 6 and drive head 7 down into the range of magazine 16 where the lengths of pipe 17 of the casing are held. Like the embodiment described above, these magazines also each have a locking device 20, so that the length of pipe 17 of the casing in the working position is connected in the same way to drive head 8 so it cannot twist.
After connecting length of pipe 13 to the pipe projecting out of the ground and after similarly connecting length of pipe 17 to the part of the drill column projecting out of the ground, drive heads 7 and 8 are detached from the respective pipes 13 and 17 by means of device 11 and returned to their starting positions.
After finishing the borehole, the lengths of pipe are moved back into the area of the respective magazines after they are first loosened by device 11 and the screw connection. Again, the corresponding locking device 20 is operated to finally disconnect the respective drive heads 7 and 8 and pipes 13 and 17, and it hold pipes 13 and 17 which are in working position in the respective magazine area until the connection between these pipes and the respective drive heads 7 and 8 has again been released. The lengths of pipe are thus moved back out of the working position into the storage position within the respective magazine 12 or 16.
In order to satisfactorily hold and guide the lengths of pipe 13 and 17 in the respective magazines 12 and 16, the respective center axis 14 can be provided with a roller guide 28, as seen in FIG. 4. As seen in FIG. 5, the roller guide 28 has two coaxial rollers 29 and 30 surrounding a guide slot 31 on both sides. Thus, the respective length of pipe 13 or 17 can be guided between the respective rollers 29 and 30 within the guide slot 31, and this provides a firm bearing.
As seen in FIG. 8, it is possible to provide the track-laying vehicle 2 with a working platform 32 that can be raised and lowered by means of articulated arm 33 and 34 in the area of carriage 4. The articulated arms 33 and 34 are part of a four-bar linkage with a coupler 39 and a bearing mount 45 next to the articulated arms 3 on the track-laying vehicle 2. This is a double rocker with the two articulated arms 33 and 34 and with coupler 39, and a total of four joints 35, 36, 37 and 38 are provided. The working platform 42 is attached to the rocker 39.
Between the two articulated arms 33 and 34, there is a piston-cylinder unit 41 with one arm arranged on the housing while the other arm is connected to articulated arms 33. When the piston-cylinder unit 41 is actuated, the two articulated arms 33 and 34 pivot upwardly, so that the working platform 32 moves in the direction of the arrow by means of coupler 39.
Coupler 39 is held by a piston-cylinder unit 40 on articulated arm 33 in a position that assures that the working platform 32 will always be in a horizontal plane. For this purpose, the two articulated arms 33 and 34 are designed like a telescope. The operation of the drilling tool according to the invention can be controlled and monitored reliably by means of the working platform 32. | A method for drilling holes in soil or rock, especially for producing prestressed ground anchorage. A hole is drilled by a drill column formed of lengths of pipe with a drill bit driven by a rotary and/or percussive drive. The wall of the borehole is supported by a casing formed of lengths of pipe driven by a rotary and/or percussive drive of a drilling tool. The lengths of pipe of the drill column and the casing are taken from a magazine by machine and transferred back to the magazine after drilling the hole. Each length of pipe for the drill column is taken sequentially from the magazine by the drive of the drilling tool for the drill column and each length of pipe for the casing is taken sequentially from the magazine by the drive of the drilling tool for the casing. Each length of pipe for the drill column and each length of pipe for the casing is returned sequentially to the magazine. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This patent arises from a continuation-in-part of U.S. patent application Ser. No. 12/129,159, filed on May 29, 2008, and is incorporated herein by reference in its entirety.
FIELD OF THE DISCLOSURE
The subject disclosure generally pertains to loading dock shelters and dock seal systems, and more specifically, to head curtains for such systems.
BACKGROUND
Trucks having open rear cargo bays are typically backed into alignment with a loading dock or other doorway of a building to facilitate loading and unloading of the vehicle. A significant gap is usually created between the rear of the truck and the face of the building, which exposes the interiors of the building and the truck to the outside environment during loading and unloading. Such gaps can be at least partially sealed by installing either a loading dock shelter or a loading dock seal around the perimeter of the doorway.
To seal or shelter the vehicle's rear vertical edges, dock shelters and dock seals usually have some type of lateral weather barrier installed along the side edges of the doorway. For dock shelters, the weather barrier usually shelters or seals against the vertical sides of the vehicle's trailer. An example of such an approach is shown in U.S. Pat. No. 3,322,132. Dock seals, on the other hand, usually have lateral weather barriers that are resiliently compressible for conformingly sealing against the vertical rear edges of the vehicle. An example of such an approach is shown in U.S. Pat. No. 5,125,196. Regardless of the structural design of the lateral weather barrier, the upper rear edge of the vehicle is often sealed or sheltered by a head curtain that drapes down onto the top of the vehicle as the vehicle backs into the dock.
If the head curtain is extra long to accommodate a broad range of vehicle heights, the dock shelter or dock seal might include means for vertically retracting the curtain so that the curtain length is appropriate for the height of the particular vehicle at the dock. Thus, the curtain needs to be flexible not only for deflecting in reaction to the vehicle backing into the dock, but also for enabling the curtain to be retracted. Such flexibility or compliance, however, can weaken or hinder the curtain's ability to forcibly seal against the rear upper edge of the vehicle. Thus, instead of the curtain applying sealingly tight pressure against the upper edge of the vehicle, a pliable curtain readily deflects backwards toward the doorway of the dock.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an example dock apparatus described herein.
FIG. 2 is an exploded perspective view of the example dock apparatus of FIG. 1 .
FIG. 3 is a cross-sectional view of the example dock apparatus of FIG. 1 taken along line 3 - 3 of FIG. 1 .
FIG. 4 is a cross-sectional view similar to FIG. 3 but showing a vehicle engaging the dock apparatus of FIGS. 1 , 2 , and 3 .
FIG. 5 is a cross-sectional view of the example dock apparatus of FIG. 1 taken along line 5 - 5 of FIG. 1 .
FIG. 6 is a cross-sectional view similar to FIG. 5 but showing a head curtain assembly of the dock apparatus of FIGS. 1-5 in a retracted position.
FIG. 7 is a cross-sectional view similar to FIG. 5 but showing another example dock apparatus described herein.
FIG. 8 is a cross-sectional view of the example dock apparatus of FIG. 7 with a vehicle engaging the example dock apparatus.
FIG. 9 is a cross-sectional view similar to FIG. 8 but showing a head curtain assembly of the example dock apparatus of FIGS. 7 and 8 in a retracted position.
FIG. 10 is a cross-section view similar to FIG. 3 but showing another example dock apparatus described herein.
FIG. 11 is a cross-section view similar to FIG. 10 but showing a vehicle engaging the example dock apparatus of FIG. 10 .
FIG. 12 is a cross-sectional view similar to FIG. 10 but showing another example dock apparatus described herein.
FIG. 13 is a cross-sectional view of the example of FIG. 12 but showing a vehicle engaging the example dock apparatus of FIG. 12 .
FIG. 14 is a cross-sectional view similar to FIG. 10 but showing yet another example dock apparatus described herein.
FIG. 15 is a cross-sectional view of the example of FIG. 14 but showing a vehicle engaging the example dock apparatus of FIG. 14 .
FIG. 16 is a perspective view of another example dock apparatus described herein.
FIG. 17 is a cross-sectional view of the example dock apparatus of FIG. 16 taken along line 17 - 17 of FIG. 16 .
FIG. 18 is a cross-sectional view similar to FIG. 17 but showing the example dock apparatus compressed by a vehicle.
FIG. 19 is a cross-sectional view similar to FIG. 5 but showing another example dock apparatus described herein.
FIG. 20 is a cross-sectional view similar to FIG. 19 but showing a curtain of the example dock apparatus of FIG. 19 in a retracted position.
FIG. 21 is a cross-sectional view similar to FIG. 19 but showing another example dock apparatus described herein.
FIG. 22 is a cross-sectional view similar to FIG. 21 but showing a curtain of the example dock apparatus of FIG. 21 in a retracted position.
FIG. 23 is a cross-sectional view similar to FIG. 19 but showing another example dock apparatus described herein.
FIG. 24 is a cross-sectional view similar to FIG. 23 but showing a curtain of the example dock apparatus of FIG. 23 being engaged by a vehicle.
FIG. 25 is a cross-sectional view similar to FIG. 19 but illustrating another example dock apparatus described herein having an example gutter lip.
FIG. 26 is a cross-sectional view similar to FIG. 25 but showing another example gutter lip described herein.
FIG. 27 is a perspective view of another example dock apparatus described herein.
FIG. 28 is a cross-sectional view of the example dock apparatus of FIG. 27 taken along line 28 - 28 of FIG. 27 .
FIG. 29 is a cross-sectional view similar to FIG. 28 but showing a curtain of the example dock apparatus of FIGS. 27 and 28 being deflected by a force.
FIG. 30 is a perspective view of another example dock apparatus described herein.
FIG. 31 is a cross-sectional view of the example dock apparatus of FIG. 30 taken along line 31 - 31 of FIG. 30 .
FIG. 32 is a cross-sectional view similar to FIG. 31 but showing the example dock apparatus of FIG. 31 being engaged by a vehicle.
FIG. 33 is a perspective view of another example dock apparatus described herein.
FIG. 34 is a cross-sectional view of the example dock apparatus of FIG. 33 taken along line 34 - 34 of FIG. 33 .
FIG. 35 is a cross-sectional view similar to FIG. 34 but showing the example dock apparatus of FIGS. 33 and 34 being engaged by a vehicle.
FIG. 36 is a perspective view of another example dock apparatus described herein.
FIG. 37 is a cross-sectional view of the example dock apparatus of FIG. 36 taken along line 37 - 37 of FIG. 36 .
FIG. 38 is a cross-sectional view similar to FIG. 37 but showing the example dock apparatus of FIG. 37 being engaged by a vehicle.
FIG. 39 is a cross-sectional view similar to FIG. 5 but showing another example dock apparatus described herein.
FIG. 40 is a cross-sectional view similar to FIG. 39 but showing the example dock apparatus of FIG. 39 being engaged by a vehicle.
DETAILED DESCRIPTION
FIGS. 1-6 show a loading dock apparatus 10 that helps seal and/or shelter the rear access opening of a truck/trailer vehicle 12 at a loading dock 14 . Dock 14 includes a doorway 16 in a wall 18 of a building. The dock apparatus 10 provides a barrier to weather and other elements as the vehicle's cargo is being loaded or unloaded at the doorway. To accommodate vehicles of various heights, dock apparatus 10 includes a head curtain assembly 20 with a retractable curtain 22 that seals along the vehicle's upper rear edge.
To seal or shelter the vehicle's rear side edges, an upper sealing assembly illustratively in the form of a head curtain assembly 20 could be used with a dock shelter that includes lateral weather barriers or side panels that are relatively rigid and incompressible. Head curtain assembly 20 , however, is particularly suited for a dock seal 24 having lateral weather barriers in the form of resiliently compressible side pads 26 , thus assembly 20 will be described and illustrated with reference to dock seal 24 .
Lateral edges 28 of curtain 22 preferably seal against the inner surfaces of side pads 26 (as shown in FIG. 3 ) and/or seal against an inner surface 30 of a pair of flexible boots 32 that protect the upper ends of side pads 26 . A touch-and-hold fastener 27 (e.g., a fabric hook-and-loop fastener such as VELCRO™) can help seal edges 28 to surface 30 . As an alternative to conventional windstraps, an inner flexible panel 29 on boot 32 is coupled to wall 18 to help prevent vehicle 12 from pulling curtain assembly 20 away from wall 18 as vehicle 12 departs dock 14 . The connection 27 between edges 28 and surface 30 also helps prevent curtain assembly 20 from uncontrolled movement in strong winds when not engaged by a vehicle. To minimize wear, side pads 26 may include one or more cavities 31 ( FIG. 2 ) that reduce the compressive forces in certain localized areas, such as in the area behind boots 32 .
When side pads 26 are compressed by the rear end of vehicle 12 , as shown in FIG. 4 , pads 26 tend to bulge and push inward against the lateral edges 28 . To maintain a positive seal at edges 28 , a resiliently compressible foam panel 34 (covered by item 38 ) may be included to increase the rigidity or stiffness (e.g., horizontal rigidity) to curtain 22 . In addition to improved sealing at edges 28 , the curtain's increased horizontal stiffness in conjunction with pads 26 bulging inward firmly retains curtain 22 between pads 26 , and the bulging sections forcibly hold curtain 22 sealingly tight against the rear upper edge of vehicle 12 .
To ensure that the horizontal stiffness does not hinder the curtain's ability to retract vertically from the position of FIG. 5 to that of FIG. 6 , foam panel 34 includes a series of compressed indentations 36 or bending creases that render panel 34 more flexible about a horizontal axis than about a vertical axis. Indentations 36 can be created or formed by sewing panel 34 to a pliable cover 38 , in which the sewing process produces a plurality of stitches 40 that holds the indentations in compression. Other methods of producing compressed indentations 36 include, but are not limited to, localized ultrasonic or heat sealing of cover 38 to foam panel 34 or localized ultrasonic or heat sealing of foam panel 34 to itself. Regardless of how indentations 36 are formed, maintaining foam panel 34 as a unitary piece, as opposed to a plurality of segments, simplifies manufacturability and provides a neat, clean appearance.
The assembly of dock apparatus 10 is perhaps best understood with reference to FIGS. 2 and 5 . Side pads 26 can be attached to wall 18 using any suitable means including, but not limited to, methods that are well known to those of ordinary skill in the art. To support foam panel 34 , curtain 22 , and an upper sheet 42 extending from curtain 22 , the head curtain assembly 20 of the illustrated example includes a resiliently crushable support panel 44 atop side pads 26 . In some examples, support panel 44 comprises a semi-rigid polymeric sheet 46 (e.g., polyethylene, polypropylene, fiberglass, etc.) encased within a pliable cover 48 . The semi-rigidity panel 44 makes it more impactable and durable than other conventional frameworks that are substantially rigid and readily damaged by vehicular impact. Panel 44 may be designed so that it could be impacted by a vehicle and compressed all the way to the loading dock wall without damage—a function not found in a conventional rigid frame.
A touch-and-hold fastener 50 (e.g., a fabric hook-and-loop fastener such as VELCRO™) can be used to contain sheet 46 within cover 48 . A resiliently flexible horizontal elongate polymeric stay 52 (e.g., rod, bar, tube, etc. made of polyethylene, polypropylene, fiberglass, etc.) can be attached to panel 44 to provide support panel 44 with additional stiffness. Stay 52 can be held within a sleeve illustratively depicted as a loop of material 54 so that stay 52 can be readily replaced if necessary. A tube 56 or bar anchored to wall 18 via a series of fasteners 58 can be used for attaching an upper flange of support panel 44 to wall 18 .
To provide head curtain assembly 20 with various components that can be readily replaced individually, touch-and-hold fasteners can be used throughout the assembly. A touch-and-hold fastener 60 , for example, can attach an upper end of the creased foam panel's cover 38 to upper sheet 42 , and another touch-and-hold fastener 62 can connect the lower end of cover 38 to a lip 64 extending from curtain 22 , thereby removably attaching foam panel 34 to curtain 22 . An additional touch-and-hold fastener 66 can removably attach cover 38 to support panel 44 . Other touch-and-hold fasteners 68 and/or 70 can fasten upper sheet 42 to support panel 44 and/or to a flap 72 anchored to wall 18 . Flexible boots 32 that help protect the upper ends of side pads 26 can also be removably attached using a touch-and-hold fastener 74 so that boots 32 are readily replaceable.
A resiliently flexible horizontal polymeric stay 76 (e.g., rod, bar, tube, etc. made of polyethylene, polypropylene, fiberglass, etc.) can be attached to the lower end of curtain 22 to provide curtain 22 with additional horizontal stiffness. Stay 76 can be held within a loop of material 78 so that stay 76 can be readily replaced if necessary. Stay 76 with or without additional weight can also help hold curtain 22 taut (e.g., vertically taut) so that curtain 22 can lie relatively flat when fully extended, as shown in FIG. 5 .
To raise curtain 22 from its position of FIG. 5 to that of FIG. 6 , a pull cord 80 (i.e., any pliable elongate member, such as a rope, strap, chain, etc.) attached to a lower end of curtain 22 can be threaded through a series of pulleys or eyelets 82 with one end 84 of cord 80 available for an operator (e.g., a manual operator or a mechanical operator)) to pull cord 80 so as to raise curtain 22 . If cord 80 is manually pulled, curtain 22 can be held at a raised position by temporarily securing cord 80 to a cleat 86 anchored to wall 18 , as shown in FIG. 6 .
In another example, FIGS. 7 , 8 and 9 illustrate another example dock apparatus 88 having a head curtain assembly 90 . In this example, dock apparatus 88 comprises a front curtain 92 suspended between two lateral weather barriers 26 . To accommodate vehicles of various heights, a pliable elongate member 94 (e.g., a pull cord, rope, strap, chain, etc.) is coupled to a distal end 96 of front curtain 92 to selectively position distal end 96 between a lowered position ( FIG. 7 ) and a raised position ( FIG. 9 ). To adjust the height of curtain 92 , elongate member 94 can be actuated by a motorized hoist 98 or manually pulled and released.
To ensure that front curtain 92 seals firmly against the rear of vehicle 12 , a stiffener 100 is installed behind front curtain 92 . Stiffener 100 is less flexible than front curtain 92 and is a horizontally elongate member that extends between the two lateral weather barriers 26 such that stiffener 100 becomes compressed horizontally between the two lateral weather barriers 26 as the lateral weather barriers are compressed by vehicle 12 . Although the actual structure of stiffener 100 may vary, in some cases, stiffener 100 comprises a resilient foam cylinder 102 reinforced by a plastic tube 104 . For additional stiffness, a resiliently flexible rod 106 can be attached to distal end 96 of front curtain 92 .
In some examples, curtain assembly 90 includes a rear curtain 108 that helps contain and protect stiffener 100 and a lower section of elongate member 94 . The lower end of rear curtain 108 connects to distal end 96 of front curtain 92 . An upper end 110 of rear curtain 108 connects to the back side of front curtain 92 with one or more openings 112 for feeding elongate member 94 from the interior space between curtains 92 and 108 and externally mounted hoist 98 or cleat 86 ( FIG. 5 ).
To help prevent stiffener 100 from escaping between curtains 92 and 108 , a pliable retention member 114 may be used to attach stiffener 100 to an upper or lower end of curtain 92 and/or curtain 108 . In some cases, retention member 114 is a sheet of pliable material that extends about the full length of stiffener 100 .
Operation of dock apparatus 88 could begin with apparatus 88 in the lowered position, as shown in FIG. 7 . Vehicle 12 backs into the dock and compresses the two lateral weather barriers 26 , as shown in FIG. 8 . In this position, lateral weather barriers 26 bulge inward toward each other (similar to FIG. 4 ), thereby holding stiffener 100 firmly up against the rear of vehicle 12 . To prevent front curtain 92 from obstructing the rear access opening of vehicle 12 , pliable elongate member 94 can be shorted to pull distal end 96 upward to the raised position of FIG. 9 . As pliable elongate member 94 lifts distal end 96 , front curtain 92 cradles and lifts stiffener 100 , and rear curtain 108 folds over onto itself.
Once in the configuration of FIG. 9 , bulging sections of lateral weather barriers 26 pressing stiffener 100 up against vehicle 12 holds curtain assembly 90 in the raised position, perhaps even if elongate member 100 is released (e.g., disengaged from a cleat or released by winch 98 ). However, when vehicle 12 departs while elongate member 94 is slack, curtain assembly 90 can freely and automatically fall back to the lowered position of FIG. 7 .
If hoist 98 is used for raising curtain assembly 90 (as opposed to the manual option of FIGS. 5 and 6 ), the electrical current drawn by the hoist 98 can be sensed and used as a means for automatically stopping the lift of curtain 92 . Lifting stiffener 100 from the lowered position of FIG. 8 to the raised position of FIG. 9 generally requires less current than it takes to lift stiffener 100 up and over the upper rear edge of vehicle 12 , i.e., above and beyond the stiffener's position of FIG. 9 . Such increase in current drawn by the hoist 98 could be used as a signal for stopping hoist 98 when stiffener 100 reaches its properly raised position. The operation of hoist 98 could also be controlled in concert with other dock-related equipment including, but not limited to, vehicle restraints, dock levelers, doors, vehicle sensors, etc.
To enhance a lateral weather barrier's ability to firmly hold a head curtain (e.g., including, but not limited to curtain or curtain assemblies 20 , 90 or 120 ) up against the rear of vehicle 12 , a lateral weather barrier can be provided with a flexible inner surface that is shaped such that the surface bulges in a particularly advantageous manner. Examples of such surfaces are illustrated in FIGS. 10-15 . The surfaces in these examples are part of a boot, wherein the boot is considered as being part of a lateral weather barrier (i.e., the lateral weather barrier includes the boot). Such functionality was not possible in previous systems that did not have adequate lateral stiffness to be held in place by the inwardly-bulging lateral weather barriers 26 .
In FIGS. 10 and 11 , two inner surfaces 116 of the boots of lateral weather barriers 118 allow some lateral clearance or light interference with curtain 120 when vehicle 12 is spaced apart from weather barriers 118 , as shown in FIG. 10 . Under compression by vehicle 12 , however, surfaces 116 bulge toward each other to hold curtain 120 firmly against vehicle 12 , as shown in FIG. 11 . Surfaces 116 can be provided by a resiliently flexible panel similar to panel 29 of FIG. 2 .
In FIGS. 12 and 13 , two inner surfaces 122 of the boots of lateral weather barriers 118 allow some lateral clearance or light interference with curtain 120 when vehicle 12 is spaced apart from weather barriers 118 , as shown in FIG. 12 . Under compression by vehicle 12 , however, surfaces 122 bulge toward each other to hold curtain 120 firmly against vehicle 12 , as shown in FIG. 13 . Surfaces 122 , in some examples, are provided by a resiliently flexible panel sewn or otherwise attached to a panel similar to panel 29 of FIG. 2 . Such resiliently flexible panels enhance the pinching action of surfaces 122 against the lateral edges of curtain 120 .
In FIGS. 14 and 15 , two inner surfaces 124 of the boots of lateral weather barriers 118 allow some lateral clearance or light interference with curtain 120 when vehicle 12 is spaced apart from weather barriers 118 , as shown in FIG. 14 . Under compression by vehicle 12 , however, surfaces 124 bulge toward each other to hold curtain 120 firmly against vehicle 12 , as shown in FIG. 15 . Surfaces 124 can be provided by a resiliently flexible panel sewn or otherwise attached to a panel similar to panel 29 of FIG. 2 .
It should be noted that existing dock seals with a compressible foam head pad can be retrofitted with the head curtain assemblies disclosed herein. In replacing an existing head pad, however, it may be beneficial to add a short vertical extension onto the existing side pads so that the new head curtain assembly is at sufficient height properly service vehicles of varying heights. Such an extension could be made similar to lateral weather barrier 26 , only significantly shorter. The extension can include cavity 31 to reduce compressive forces at the boot.
In the example of FIGS. 16-18 , a loading dock apparatus 130 includes a stiffener 132 at each upper corner to help ensure that upon vehicle 12 compressing two lateral weather barriers 26 , the barriers 26 bulge inward toward each other to seal against the lateral edges 28 of front head curtain 22 . In this example, each of the lateral weather barriers 26 are shown as resiliently compressible side pads, wherein each pad comprises a foam core contained within a pliable cover. FIG. 17 shows dock apparatus 130 prior to being compressed by vehicle 12 , and FIG. 18 shows apparatus 130 in compression or being engaged by the vehicle 12 .
In some examples, the length of dimension of stiffener 132 (e.g., vertically elongate) is shorter than the lengths of pads 26 , and is made of a stiffer material (e.g., fiberglass) than that of pad 26 and/or boot 32 . In the illustrated example, each stiffener 132 is disposed in the vicinity of upper sealing member (e.g., front curtain 22 ) and positioned to place the two pads 26 between the two stiffeners 132 . In this position, stiffeners 132 resists the pad's tendency to bulge away from each other, thus the pads 26 are more inclined to bulge inward to press its inner surfaces 134 sealingly tight against the curtain's lateral edges 28 . Although stiffeners 132 enhance or increase the amount of side pad's inward bulging, a small portion of pad 26 might still bulge into an area 136 that is between wall 18 and stiffeners 132 .
In the example of FIGS. 19 and 20 , a dock apparatus 138 comprises a retractable front curtain 140 suspended from an overhead support panel 142 . Curtain 140 is schematically illustrated to represent any retractable single sheet of material, multi-sheet of material, foam panel, pliable cover, and/or various combinations thereof. Curtain 140 , for example, may include one or more of the construction details of the curtain shown in FIG. 5 or 7 . Curtain 140 , however, does not utilize retention member 114 ( FIG. 7 ) fastened to a roller 142 (e.g., stiffener 100 of FIG. 7 ). Instead, roller 142 is cradled in a sling 144 provided by curtain 140 with the support of pliable elongate member 94 .
To retract curtain 140 , elongate member 94 pulls a lower edge 146 of curtain 144 from a lowered position ( FIG. 19 ) to a raised position ( FIG. 20 ). As lower edge 146 moves from its lowered position to its raised position, lower edge 146 rises between roller 142 and an imaginary plane 148 defined by wall 18 .
In another example, shown in FIGS. 21 and 22 , elongate member 94 retracts a curtain 140 ′ in a somewhat reversed manner compared to the curtain 140 of FIGS. 19 and 20 . As lower edge 146 moves between a lowered position and a raised position, roller 146 at some point becomes interposed between lower edge 146 and wall plane 148 . The arrangement of FIGS. 19 and 20 can make it easier to retract curtain 140 with less effort, but the arrangement of FIGS. 21 and 22 can pull curtain 140 ′ more tightly against a rear edge of vehicle 12 for better sealing.
In another example, shown in FIGS. 23 and 24 , a dock apparatus 150 comprises a front curtain 152 suspended from an overhead support panel 154 . Curtain 152 is schematically illustrated to represent any retractable single sheet of material, multi-sheet of material, foam panel, pliable cover, and/or various combinations thereof. Curtain 152 , for example, may include one or more of the construction details of the curtain shown in FIG. 5 or 7 . In this example, support panel 154 is relatively stiff to help support the weight of curtain 152 yet is resiliently flexible to bend between a relaxed position ( FIG. 23 ) and a strained position ( FIG. 24 ).
In this example, an anchor bar 156 (e.g., structural angle, structural channel, tube 56 , etc.) is firmly attached to wall 18 and support panel 154 to help hold panel 154 at its relaxed position and to help panel 154 resist deflecting to its strained position. As vehicle 12 backs into or otherwise engages curtain 152 , the friction between curtain 152 and vehicle 12 pulls curtain 152 downward, which pulls a distal edge 158 of support panel 154 downward toward (e.g., closer) to wall 18 . As this occurs, the deflection resistance of support panel 154 urges curtain 152 sealingly tight up against a rear edge of vehicle 12 .
In some examples, to further support panel 154 at its relaxed position of FIG. 23 , dock apparatus 150 can be used in conjunction with a resiliently flexible horizontally elongate stay (e.g., stay 52 of FIG. 5 ) resting atop two lateral weather barriers (e.g., side pad 26 of FIG. 5 ).
In some examples, as shown in FIG. 25 , a dock apparatus 160 includes a gutter lip 162 extending along and protruding upward from a distal edge 164 of a support panel 166 . Lip 162 helps deflect water that might drain down across the upper surface of panel 166 , from a proximal edge 168 of panel 166 to distal edge 164 , thus inhibiting the drainage from dripping between the rear of vehicle 12 and doorway 16 . In some examples, as shown in FIG. 25 , lip 162 is an integral extension of panel 166 , whereby lip 162 and panel 166 comprise a unitary piece. In other examples, as shown in FIG. 26 , a gutter lip 170 is in the form of a resiliently flexible piece 172 contained within a pliable cover 174 . Pliable cover 174 , in some examples, also covers a support panel 176 .
In some cases, the upper rear edge of a vehicle includes a rearward protrusion, such as hardware associated with a rear door latch. To help prevent such a protrusion from poking through a front curtain or front pad of a dock seal or shelter, an example dock apparatus 178 , shown in FIGS. 27-29 , includes a retractable front curtain 180 suspended from a support panel 182 . Curtain 180 includes an inner region 184 that has a greater penetrating force tolerance than that of an outer peripheral region 186 of the curtain 180 . A region having “greater penetrating force tolerance” means that for a given protrusion pressing with a given force (once or repeatedly) against the region, the region will experience less permanent damage than another region subject to the same pressing force. FIG. 28 shows curtain 180 without being subjected to a penetrating force, and FIG. 29 shows curtain 180 reacting to a penetrating force 188 from a vehicle.
To achieve greater penetrating force tolerance, in some examples, front curtain 180 includes two slits 190 that flank inner region 184 . Slits 190 provide inner region 184 with greater flexibility or more freedom to flex in reaction to penetrating force 188 , as slits 190 make inner region 184 less constrained by outer region 186 . To prevent air and water from leaking through slits 190 , an expansion joint 192 covers each slit 190 . In some examples, expansion joint 192 is a web of flexible material with one edge 194 folded back onto itself with the entire perimeter of the web being sewn or otherwise attached to the back side of curtain 180 .
In some examples, as shown in FIGS. 30-32 , a series or plurality of overlapping pleats 196 cover inner region 184 of curtain 180 to provide several benefits. Pleats 196 provide curtain 180 with even greater penetrating force tolerance, greater wear resistance, and/or improved sealing against an upper surface 198 of vehicle 12 . As vehicle 12 backs into curtain 180 , pleats 196 deflect as shown in FIG. 32 to press sealingly tight downward against the vehicle's upper surface 198 . In other examples, pleats 196 can be added to other example curtains and/or header pads (e.g., the curtains 32 , 92 , 12 , 140 , 140 ′, and 152 described herein), even the curtains or head pads without additional features (e.g., slits) that make the curtains and/or header pads more tolerant of penetrating forces.
In some examples, as shown in FIGS. 33-35 , a dock apparatus 200 includes a curtain 202 with a series of flexible loops 204 instead of pleats 196 . Loops 204 , in some examples, are made of a flexible material similar to the material of curtain 202 and can be sewn or otherwise attached to the front face of curtain 202 or attached to the front face of a foam header pad via any other suitable fastener such as, for example, Velcro®, adhesive, etc. Loops 204 provide the front face of curtain 202 with more compliance to seal against vehicle 12 . Such compliance can also make curtain 202 more tolerant of rearward protrusions on vehicle 12 .
In some examples, shown in FIGS. 36-38 , a dock apparatus 206 includes a retractable curtain 208 with a series of pleats 210 overlapping a series of loops 212 . In this example, loops 212 are more triangular than U-shaped or bell-shaped, and loops 212 bias pleats 210 in a generally outward projection. As vehicle 12 backs into curtain 208 , loops 212 urge pleats 210 down into and against vehicle 12 . Loops 212 in combination with pleats 210 not only provide the front face of curtain 208 with more compliance to seal against vehicle 12 but also provides curtain 208 with more tolerance of rearward protrusions on vehicle 12 .
In some examples, shown in FIGS. 39 and 40 , a dock apparatus 214 comprises a resiliently compressible header 216 that is substantially horizontally elongate and mounted in proximity with an overhead edge 218 of doorway 16 . In this example, header 216 comprises a resiliently compressible foam core 220 contained within a pliable cover 222 . A cavity 224 (e.g., a collapsible cavity) defined by foam core 220 renders header 216 more tolerant of rearward protrusions on vehicle 12 . In some examples, core 220 is a single piece of foam defining cavity 224 , and in other examples, the header's foam core is comprised of multiple foam pieces. In the illustrated example, the header's foam core 220 is comprised of two foam pieces 220 a and 220 b.
To provide header 216 with greater penetrating force tolerance, greater wear resistance, and improved sealing against upper surface 198 of vehicle 12 , header 216 includes a plurality of pleats 226 overlying cover 222 such that cavity 224 is between foam core 220 and pleats 226 . As vehicle 12 backs into header 216 , pleats 226 deflect as shown in FIG. 40 to press sealingly tight downward against the vehicle's upper surface 198 . To seal along the rear vertical edges of vehicle 12 , some examples of dock apparatus 214 also include a pair of resiliently compressible weather barriers 26 that are installed along the lateral vertical edges of doorway 16 .
While plurality of pleats 226 may be particularly effective at sealing against vehicle 12 when pleats 226 are used in conjunction with cavity 224 , plurality of pleats 226 may also provide an effective seal against vehicle's upper surface 198 , even without cavity 224 . In a header without foam piece 220 b and cavity 224 , cover 222 would tightly overlay foam core 220 and a plurality of pleats 226 would overlay a front face of cover 222 . As vehicle 12 backs into header 216 , lower portion of foam core 220 compresses, pushing pleats 226 out and causing pleats 226 to deflect and press sealingly tight downward against the vehicle's upper surface 198 . In this manner, pleats 226 effectively cover any gaps that may otherwise exist between cover 222 and vehicle 12 and divert rain water away from the header 216 . Typically, pleats are often used exclusively on loading dock side pads (e.g., side pads 26 of FIG. 1 ) to provide increased wear resistance to the covers of the side pads (lateral edges of a vehicle rub against the side pads as the vehicle is loaded or unloaded), but the current example utilizes pleats 226 on header 216 as sealing and rain diversion devices. The pleats 226 on header 216 may span the entire length of the header (spanning substantially the entire gap between side pads 26 ) to provide effecting sealing and rain diversion across the entire width of vehicle 12 .
At least some of the aforementioned examples include one or more features and/or benefits including, but not limited to, the following:
In some examples, a dock apparatus includes a retractable head curtain that is more flexible about a horizontal axis than a vertical axis.
In some examples, the head curtain is supported by a resiliently compressible, creased foam panel.
In some examples, the creases in the foam panel are created by sewing the foam panel to a pliable cover using a series of horizontal stitch lines.
In some examples, the foam panel is removably attached to the head curtain.
In some examples, the head curtain is removably attached to a support panel.
In some examples, the support panel is stiffened by a readily replaceable fiberglass stay.
In some examples, the lower end of the head curtain is stiffened by a readily replaceable fiberglass stay.
In some examples, the dock apparatus includes a pair of protective boots that are readily replaceable.
Although certain example methods, apparatus, and articles of manufacture have been described herein, the scope of coverage of this patent is not limited thereto. On the contrary, this patent covers all methods, apparatus, and articles of manufacture fairly falling within the scope of the appended claims either literally or under the doctrine of equivalents. | Head curtains for dock shelters or dock seals are disclosed. An example head curtain assembly for a vehicle loading dock includes a retractable curtain stiffened by a resiliently compressible foam panel that is more flexible about a horizontal axis than about a vertical axis. The difference in directional flexibility can be created by sewing the foam panel to a pliable cover using a series of parallel horizontal thread lines. The thread lines create in the foam a series of compressed indentations that run horizontally across the curtain so that the curtain tends to bend more easily along those lines. The relative stiffness in the horizontal direction enables the curtain to exert an appreciable sealing force against two lateral dock seal members, and the vertical flexibility makes the curtain easy to retract to accommodate vehicles of various heights. Touch-and-hold fasteners make many of the individual components of the head curtain readily replaceable. | 4 |
FIELD OF THE INVENTION
[0001] The present invention relates tools and techniques to radially expand a downhole tubular in a well. More particularly, this invention relates to a liner hanger expander with improved tool release features.
BACKGROUND OF THE INVENTION
[0002] Various types of liner hanger have been proposed for hanging a liner from a casing string in a well. Many liner hangers are set with slips activated by the liner hanger running tool. Liner hangers with multiple parts pose a significant liability when one or more of the parts become loose in the well, thereby disrupting the setting operation and making retrieval difficult. Other liner hangers and running tools cannot perform conventional cementing operations through the running tool before setting the liner hanger in the well.
[0003] Conventional liner hangers have problems supporting heavy liners with the weight of one million pounds or more. Some liner hangers successfully support the liner weight, but do not reliably seal with the casing string. Other liner hangers are not able to obtain burst and/or collapse characteristics equal to that of the casing. A preferred liner hanger maintains a collapse and burst strength at least substantially equal to that of both the casing and the liner.
[0004] Another significant problem with some liner hangers is that the running tool cannot be reliably disengaged from the set liner hanger for retrieval to the surface. This problem with liner hangers becomes more involved with the desirability to rotate the liner with the work string in the well, e.g., for a liner drilling operation, wherein the operator desires to disengage the work string and tool when the liner hanger has been set, thereby allowing the running tool and the work string to be retrieved from the well.
[0005] Publication 2001/0020532A1 discloses a tool for hanging a liner by pipe expansion. U.S. Pat. No. 3,948,321 discloses a reinforcing swage which remains downhole when the tool is retrieved to the surface. U.S. Pat. No. 6,705,395 discloses a radially expanded liner hanger which uses an axially movable annular piston to expand a tubular member. U.S. Pat. Nos. 7,225,880 and 7,278,492 disclose an expandable liner hanger system and method.
[0006] The disadvantages of the prior art are overcome by the present invention, and an improved liner hanger system and method of releasing the liner hanger are hereinafter disclosed.
SUMMARY OF THE INVENTION
[0007] An expandable liner hanger system and method achieves positioning, suspension, sealing and optional cementing of a liner in a subterranean well. In an exemplary application, the method involves expansion of a high strength steel tubular hanger body having slips and packing elements positioned about its outer circumference for contact with the inner surface of a casing string, which has a larger internal diameter than the initial external diameter of the liner and liner hanger when run in the well through the casing string.
[0008] The present invention preferably uses a tubular expander to expand the hanger body, and the tubular expander remains inside the expanded hanger body for support at its final expanded diameter, thus sandwiching the expanded plastically deformed hanger body between the outer casing and the tubular expander. This method provides improved sealing and gripping capability, and requires shorter lengths of expandable tubular liner hanger, typically in the range of from one to five feet.
[0009] In the preferred embodiment, three different mechanisms for release of the tool from the liner hanger may be used. In the first technique, a retainer is secured to the tool mandrel, and the downward movement of the work string and thus the mandrel and the retainer releases collet fingers connecting the tool mandrel to the tubular hanger, thereby releasing the tool so that it may be retrieved to the surface. The tool is also provided with hydraulic piston supported on the mandrel to selectively engage and disengage a clutch rotatably connecting the tool mandrel and a housing supporting latching members. When the clutch is engaged, rotation of the work string rotates the mandrel and a bit at the lower end of the liner. The latching members rotatably connect the tubular hanger and a supporting housing, such that when the clutch is disengaged, rotation of the mandrel arm will unthread the retainer which is rotatably connected to the tubular hanger, thereby providing a separate release mechanism to retrieve the tool to the surface. A safety joint is threadably connected to the tool mandrel and an upper collet retainer, such that left-hand rotation of the mandrel releases an upper portion of the mandrel from the clutch, thereby providing a third release mechanism.
[0010] These and further features and advantages of the present invention will become apparent from the following detailed description, wherein reference is made to the figures in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 illustrates in cross-section an upper portion of the tool positioned within a casing.
[0012] FIG. 2 illustrates a lower portion of the tool, including portions of a hydraulic actuator.
[0013] FIG. 3 illustrates an intermediate portion of the tool, and specifically shows the safety release joint.
[0014] FIG. 4 illustrates a lower portion of the tool with a collet mechanism and dogs rotatably engaging the tool and the liner.
[0015] FIG. 5 illustrates a lower portion of the tool with a ball seat.
[0016] FIG. 6 illustrates a cementing plug on a still lower portion of the tool.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0017] A liner may be conveyed into the well to the desired setting or suspension depth by a drill pipe or work string connected to a multi-stage, double action hydraulic setting and releasing tool (running tool) that furnishes the necessary forces to expand the liner hanger assembly into engagement with the casing. The running tool may be constructed of sufficiently high strength steel to support the weight of the liner as it is run into the well and to provide the necessary force to expand the liner hanger assembly. Additionally, the running tool preferably has a sufficiently large internal bore in its central mandrel to enable passage and displacement of cement for cementing the liner within the well bore.
[0018] Referring to FIG. 1 , the upper end of the running tool 10 may include a hydraulic actuator assembly 12 , which is shown in greater detail in FIG. 2 . A top connector 14 is structurally connected by threads 16 to a work string (not shown), and to the running tool inner mandrel 34 . One or more seals 24 provide dynamic sealing of connector 14 and outer sleeve 22 , and threads 26 connect 14 and mandrel 34 . A throughport 31 in the mandrel 34 allows fluid pressure within the interior of the running tool to act on the outer piston 28 , which as shown includes conventional seals 33 for static sealing with the outer sleeve 22 and seals 32 for dynamic sealing with the mandrel 34 . Threads 30 structurally connect the outer piston 28 to outer sleeve 22 . A predetermined amount of fluid pressure within the running tool acting on the outer piston 28 will thus provide downward movement of the outer sleeve 22 .
[0019] Shear ring 18 engages shoulder 17 on connector 14 , and is threaded to outer sleeve 22 and rotatably pinned to outer sleeve 22 by one or more pins 20 , 21 . Shear ring 18 prevents activation of the tool until a predetermined amount of pressure is applied to generate force sufficient to break the reduced wall section 19 and thereby allow upward movement of connector 14 and mandrel 34 relative to the outer sleeve 22 . Pins 20 , 21 slide within slots 23 to provide non-rotational interconnection between the outer sleeve 22 and the mandrel 34 .
[0020] Referring now to FIG. 2 , an inner piston 40 is threadably connected to the mandrel 34 by threads 42 . Ports 36 in the mandrel allow for passage of fluid between the inner piston 40 and a lower outer piston 28 . The inner piston 40 includes one or more static seals for sealing engagement with the mandrel, and includes one or more dynamic seals 38 for dynamic sealing engagement with the outer sleeve 22 . Outer piston 28 in turn includes static seals for sealing with the outer sleeve 22 , and dynamic seals 32 for sealing engagement with the mandrel 34 . Ports similar to 36 may be provided at various locations in the mandrel to provide for the reliable actuation of the inner and outer pistons. FIG. 2 also depicts another lower inner piston 40 threaded to the mandrel 34 and also containing static seals for sealing with the mandrel, and dynamic seals for sealing with the outer sleeve 22 . A lower sealing block 42 is threadably connected by threads 44 to outer sleeve 22 , and similarly contains outer static seals for sealing with outer sleeve 22 and inner dynamic seals for sealing engagement with the mandrel 34 .
[0021] The lower end of the sealing block 42 includes threads 48 for threaded engagement with sleeve 50 , which as shown in FIG. 3 , contains a retainer 52 threaded at 54 to sleeve 50 , and including one or more shear pins and shear sleeve 58 for engaging the shoulder 59 on tubular expander 60 . FIG. 2 depicts the upper end 56 of the expander body show more clearly in FIG. 3 . Expander 60 preferably includes a plurality of annular radially outer bumps 62 and a lower tapered portion 74 for increasing the diameter of the tubular hanger when moved downward relative to the liner hanger. The lower end of the mandrel 34 is threaded at 64 to upper connector 66 , which is threaded at 68 to lower connector 70 . Threads 72 secure the lower connector to the lower portion of the mandrel 34 .
[0022] As shown in FIGS. 3 and 4 , the tubing hanger 90 includes an upper hanger body 80 with a plurality of vertically spaced slips 76 and packing or other sealing elements 78 . Collet mechanism 86 includes lower collets which are threaded at 88 to the body of the tubing hanger 90 . Nut 92 is threaded at 94 to the mandrel 34 . Upward movement of the nut relative to the mandrel is prevented by sleeve retainer 84 which is threaded at 85 to the mandrel 34 .
[0023] The lower end of the mandrel 34 in FIG. 4 is threaded at 102 to the upper clutch body 96 , which includes a downwardly extending member 106 which fits within a suitable receptacle 104 provided in the lower clutch body 112 . Circumferentially spaced dogs or similar blocks 107 are outwardly biased by respective springs 108 for engaging an axial spline in the liner body 100 , thereby rotatably interconnecting the block 112 and the liner. Conventional static seals 110 are also provided. The dogs 107 rotatably connect the liner to the block 112 thereby allowing rotation at the liner and a bit at the lower end of the liner when the mandrel 34 and the clutch formed by engagement of 104 and 106 . Ports 162 in mandrel extension 105 allow pressure to act on the smaller diameter seal to force block 112 downward, thereby disengaging the clutch. Mandrel 105 as shown in FIG. 5 thus rotates within the block 112 .
[0024] FIG. 5 shows the lower end of the liner connected to the liner body 100 connected to the liner L by threads 114 . Ball seat 120 is also shown in FIG. 5 , and is initially retained in an upper position with respect to sleeve 116 by a plurality of pins 124 . The sleeve 120 moves downward relative to sleeve 116 and when pins 124 shear, thereby opening ports 125 to fluid internal of the mandrel. The lower end of the sleeve 116 is threaded at 122 to lower mandrel extension 126 .
[0025] Referring now to FIG. 6 , mandrel sleeve 126 passes through guide block 140 , which includes seal 134 and retainer 136 for sealing with sleeve 126 , and seal 132 and guide ring 128 for sealing with liner body 100 . Cementing plug 142 is also shown in FIG. 6 , including inner sleeve 150 and port 157 . Ball seat 144 is pinned at 148 to lower wiper body 146 , which is threaded at 152 to sleeve 150 .
[0026] The liner may be run to setting depth on drill pipe and cemented in a conventional manner. The cement may be displaced from the drill pipe and liner and into the well bore/liner annulus using cement wiper plugs as is customary in the art. Once the plugs have displaced the cement and seated near the bottom of the liner, pressure may be applied to fluid within the work string and consequently through the pressure ports of the mandrel and into the pressure chambers formed between upward moving pistons and downward moving pistons. Pressure may be increased until the force created is sufficient to cause the expander to move downward, forcing the expander into the upward facing receptacle of the liner hanger body. Forcing the expander downward causes the liner hanger body to expand radially outward, forcing slips and sealing elements into engagement with the inside surface of the casing, thus sealing and supporting the liner hanger within the casing.
[0027] If pressure within the drill pipe and liner cannot be increased after landing the wiper plugs, a setting ball may be dropped into the drill pipe and permitted to gravitate until the ball engages the seat at the lower end of the running tool. Pressure may then be increased to operate the setting tool.
[0028] As disclosed herein, the tubular expander is positioned at least partially within the hanger body, thereby radially expanding at least part of the liner hanger body. In other cases, all or substantially all of the tubular expander will be within the liner hanger body when the assembly is set. Complete insertion of the tubular expander within the liner hanger body is not required, however, for all applications.
[0029] One technique for releasing the tool from the liner involves axial movement of the work string, i.e., use of the set down weight to release the tool from the liner. This technique allows the work string and thus the retainer or nut 92 threaded to the mandrel to move downward, while the collet mechanism 86 remains engaged with the tubing hanger 90 . This downward movement thus allows the collet fingers to be released in the retainer 92 , so the entire tool may be retrieved to the surface by subsequently pulling the work string. While this operation is relatively simple and reliable, it does require that the work string be moveable downward relative to the liner, which may not be possible if the hydraulic pistons have stroked the expander 60 to a downward position to expand the hanger body 80 .
[0030] Another technique for releasing the tool from the liner involves the use of hydraulic fluid to pass through the ports 162 as shown in FIG. 4 , thereby pressurizing the lower clutch body 112 , which acts as a piston. This action disengages the downward extending member 106 from the receptacle 104 , which allows the work string and thus the mandrel 34 to be rotated while the dogs 107 maintain the tubing hanger 90 stationary. This rotation will thus lower the retainer 92 with respect to the mandrel, and continued rotation of the work string effectively disengages the retainer or nut 92 from the collet mechanism 86 , thereby allowing the collets to collapse so that tool may be retrieved to the surface. While this operation is also reliable, it does require that fluid pressure be applied to disengage the clutch, and there may be applications wherein sufficient fluid pressure cannot be obtained downhole to accomplish the release of the tool by this mechanism.
[0031] Yet another mechanism for releasing the tool to be retrieved to surface involves rotation of the work string and thus the mandrel 34 , such that the thread 68 begins to unthread, hereby moving a lower portion of the mandrel 34 downward, and thus moving the retainer 92 downward and disengaging the retainer from the collet mechanism 86 . The thread 68 as shown in FIG. 3 may be used with one or more ball members 67 to ride within unfilled thread cavities 69 in the lower connector 70 . Once the threads 68 on the exterior of the upper connector 66 engage the ball members 67 , no further unthreading of the connection occurs, so that the upper connector 66 remains engaged with the lower connector 70 , although the lower connector 70 and the mandrel 34 beneath the upper connector 66 have moved downward axially relative to the upper connector.
[0032] According to the present invention, one technique for releasing the tool from the liner involves axial movement (set down) of the work string, while another technique involves a combination of hydraulic fluid pressure and rotation of the work string, while the third technique involves left-hand rotation of the work stream.
[0033] Although specific embodiments of the invention have been described herein in some detail, this has been done solely for the purposes of explaining the various aspects of the invention, and is not intended to limit the scope of the invention as defined in the claims which follow. Those skilled in the art will understand that the embodiment shown and described is exemplary, and various other substitutions, alterations and modifications, including but not limited to those design alternatives specifically discussed herein, may be made in the practice of the invention without departing from its scope. | A liner hanger ( 10 ) is provided for supporting a liner in a well. An expandable tubular hanger ( 90 ) is positioned within the well and a running tool with a tool mandrel ( 34 ) passes fluid through the running tool. An actuator ( 12 ) forcibly moves the tubular expander to an expanded position. Release of the running tool from the liner may be accomplished with a retainer ( 84 ) and downward movement of the mandrel, with fluid pressure acting on a hydraulic piston ( 28 ) coupled with rotation of the mandrel, or by safety joint ( 68 ) along the tubular mandrel. | 4 |
FIELD OF THE INVENTION
The present invention relates to a matrix for a molten carbonate fuel cell, and more particularly, to a matrix having high intensity by sintering at a lower temperature and the manufacturing method thereof.
BACKGROUND OF THE INVENTION
A fuel cell, which is a new electricity generation system using electrical energy directly converted from the energy produced by the electrochemical reaction of a fuel gas and an oxidant gas, is under careful examination for use as a power source, such as that for space stations, unmanned facilities at sea or along coastal areas, fixed or mobile radios, automobiles, household electrical appliances or portable electrical appliances.
Fuel cells are divided into a molten carbonate electrolyte fuel cell operating at a high temperature (in the range of about 500° C. to about 700° C.), a phosphoric acid electrolyte fuel cell operating around 200° C., an alkaline electrolyte fuel cell operating at room temperature to about 100° C., and a solid electrolyte fuel cell operating at a very high temperature (1,000° C. or above).
A molten carbonate fuel cell (MCFC) is constituted by a porous nickel anode, a lithium-doped porous nickel-oxide cathode and a lithium aluminate matrix which is filled with lithium and potassium carbonate as electrolytes. The electrolytes are ionized by melting at about 500° C., and the carbonate ions generated therefrom establish electron flow between the electrodes. Hydrogen is consumed in the anode area, which thus produces water, carbon dioxide and electrons. The electrons flow to the cathode via an external circuit to produce the desired current flow.
The matrix of an MCFC is generally composed of gamma-lithium aluminate (γ-LiAlO 2 ) to be formed as a porous tile of about 0.5-2 mm in thickness. Such a matrix supports a mixed carbonate (Li 2 CO 3 /K 2 CO 3 ), which is an electrolyte, and offers a path for carbonate ions (CO 3 -2 ) generated from the cathode to move toward the anode during operation. Further functions of the MCFC matrix are to provide electrical insulation between the electrodes, to prevent the mixing of various reactants such as fuels introduced to the respective electrodes or to the air, and to serve as a wet seal so that harmful gases do not leak from the cell. Differently from other electrochemical systems, the matrix in which electrolytes are impregnated exists as a solid at room temperatures and as a paste at 650° C., which is the operating temperature of an MCFC. Therefore, the performance of a matrix is determined by internal resistance, gas cross-over, the wet seal function of fuel cells, etc.
An MCFC matrix is subject to great stresses due to the large temperature differential which exists between room temperature and the cell operating temperature, and thus, functional stability is a prevailing problem. Therefore, investigations for overcoming the problem of functional stability are being made. For example, U.S. Pat. No. 4,322,482 disclosed that when 20 volume percent or less of lithium aluminate particles and/or alumina particles whose diameters are at least 50 microns are added to submicron lithium aluminate support particles, the formation of cracks due to temperature change is prevented. Also, U.S. Pat. No. 4,511,636 disclosed a matrix which can withstand a compression force occurring at the time of manufacture and is thus not fragile, by mixing an inert material whose diameter is less than about one micron with ceramic particles having diameters greater than about 25 microns and then adding about 35 volume percent of organic binder thereto. Here, lithium aluminate and alumina are examples of the inert material and the ceramic particles, respectively.
Lithium aluminate exists in three phases (states), namely, alpha (α), beta (β) and gamma (γ). Of these phases, the γ-phase is the most stable at MCFC operation temperature of 650° C., and matrices composed of the γ-lithium aluminate are the most widely employed.
FIG. 1 is a photograph taken by a scanning electron microscope (SEM), showing a pellet manufactured by sintering the pure γ-lithium aluminate at 1,200° C. for four hours according to a conventional method. Here, the matrix for the conventionally manufactured MCFC has relatively small (about 1 μm) γ-lithium aluminate particles. Therefore, the resultant matrix does not have adequate pore distribution and the intensity is low, since structural stability is not maintained. Also, due to a high sintering temperature used in manufacturing the matrix, the overall manufacturing cost is considerably high.
SUMMARY OF THE INVENTION
In order to solve the above problems, an object of the present invention is to provide a matrix for an MCFC having high intensity and improved quality.
Another object of the present invention is to provide a method for manufacturing the above MCFC at a low cost.
To accomplish the above first object, according to the present invention, there is provided a matrix for an MCFC of high intensity and improved quality, wherein the main component is gamma-lithium aluminate (γ-LiAlO 2 ) particles having diameters of 4-10 μm. The term "main component" is defined for purposes of this application as meaning that more of this component is present than any other component (with respect to weight percent) in the matrix of the present invention. Here, the proportion of gamma-lithium aluminate particles is preferably 60% or more by weight.
Another object of the present invention is achieved by the manufacturing method of the matrix for an MCFC comprising the steps of: grinding gamma-lithium aluminate particles; stirring the gamma-lithium aluminate particles in a solvent; saturating the stirred mixture with ammonia gas and stirring again; adding sodium metal to the restirred mixture; obtaining precipitates from the sodium-metal-added mixture; and drying and sintering the precipitates.
In particular, in the step of saturating the ammonia gas and stirring, it is preferable to impregnate 350X-450X (in milliliters) of ammonia gas and stir for 23-25 hours. Here, the variable "X" is the gross mass (in grams) of the gamma-lithium aluminate. Also, the amount of added sodium metal is preferably X/50 mol in 30-35 sub-divided portions so as not to react explosively, and the sintering is preferably performed at a temperature in the range of 600°-1,100° C. for three to five hours. The preferred solvents are ethyl alcohol, 2-propanol or a mixture thereof. For the mixture, the preferred mixing ratio of ethyl alcohol to 2-propanol is 3:7. The most preferred solvent is 2-propanol.
BRIEF DESCRIPTION OF THE DRAWINGS
The above objects and other advantages of the present invention will become more apparent by describing in detail preferred embodiments thereof with reference to the attached drawings in which:
FIG. 1 is a scanning electron microscope (SEM) picture for a pellet manufactured by sintering pure gamma-lithium aluminate at 1,200° C. for four hours according to a conventional method;
FIG. 2 is a scanning electron microscope (SEM) picture for a pellet manufactured by sintering gamma-lithium aluminate to which ammonia gas and sodium metal are added at 1,000° C. for four hours according to an embodiment of the present invention;
FIG. 3 is a scanning electron microscope (SEM) picture for a pellet manufactured by sintering gamma-lithium aluminate to which ammonia gas and sodium metal are added at 900° C. for four hours according to another embodiment of the present invention;
FIG. 4 is a scanning electron microscope (SEM) picture for a pellet manufactured by sintering gamma-lithium aluminate to which ammonia gas and sodium metal are added at 800° C. for four hours according to still another embodiment of the present invention;
FIG. 5 is a scanning electron microscope (SEM) picture for a pellet manufactured by sintering gamma-lithium aluminate to which ammonia gas and sodium metal are added at 650° C. for four hours according to yet another embodiment of the present invention;
FIG. 6 is a graph showing an X-ray diffraction analysis of pure gamma-lithium aluminate;
FIG. 7 is a graph showing an X-ray diffraction analysis of gammalithium aluminate to which ammonia gas and sodium metal are added according to the present invention; and
FIG. 8 is a diagram for explaining the manufacturing method of the matrix for the MCFC according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
By the method according to the present invention, the treatment of gamma-lithium aluminate with ammonia gas and sodium metal in an appropriate solvent allows the sintering at a relatively low temperature to produce the gamma-lithium aluminate which is high in its purity and has particles of a large diameter, thereby obtaining a matrix for an MCFC whose intensity is high and whose quality is excellent.
The method for manufacturing the matrix according to the present invention will be explained below in detail.
First, the size of γ-lithium aluminate particles is made uniform by ball milling. The γ-lithium aluminate is added to 2-propanol, from which the water is removed by a molecular sieve of 4-6Å, and stirred for about 23-25 hours. Then, ammonia gas is introduced to saturation level, and the resultant is stirred again for another 23-25 hours. Here, the ammonia gas is introduced in the amount of about 350X-450X milliliters for the gross weight "X" grams of the γ-lithium aluminate by using a flow meter to reach saturation. The apparatus for stirring the resulting mixture and impregnating ammonia gas therein is illustrated in FIG. 8.
In the apparatus shown in FIG. 8, reference numeral 2 denotes a magnetic stirrer in which magnetic force is generated by electrical power, 4 denotes a magnetic bar which is rotated by the magnetic stirrer 2, 6 denotes a mixture of γ-lithium aluminate and 2-propanol, 8 denotes a vacuum pump, 10 denotes an ammonia gas tank in which ammonia gas is filled, 12 denotes a flask holding calcium chloride therein, 14 denotes calcium chloride, 16 denotes a mixture of ice and sodium chloride, 18 denotes sodium metal, 20 is a mixture of dry ice and acetone, and 22 and 24 denote valves.
After the stirred mixture of γ-lithium aluminate and 2-propanol is saturated with ammonia gas, the resultant is stirred for 24 hours until the reaction is complete. Then, X/50 mol of sodium metal is added in small amounts such that it is subdivided 30-35 times so as to prevent an explosive reaction from happening. Thereafter, precipitates are separated from the mixture by means of a centrifuge. The acquired precipitates are dried and sintered at 600° C.-1,000° C. for three to five hours, thereby forming a high-intensity matrix according to the present invention.
In the method according to tile present invention, a chemical treatment of γ-lithium aluminate allows the particles to pass through a sol-state. Here, the diameter becomes a few nanometers. Next, sintering makes the diameter larger, and it is possible to adjust the diameter by adjusting the sintering temperature and duration.
Hereinbelow, preferred embodiments of the present invention are described in detail with reference to examples. However, the present invention is not limited to the following embodiments. Unless otherwise indicated, all parts, percents, ratios and the like are by weight.
The materials used in these experiments included γ-lithium aluminate which was ball-milled for 72 hours, 2-propanol from which the water was removed by a molecular sieve, and sodium metal (3-8 mm in caliber and 0.1 grams each). Also, 98% ammonia, dehumidified by passing through calcium chloride, was used as shown in FIG. 8 (ammonia was passed through calcium chloride 12 and 14), in anticipation of lowering the purity and water content.
The devices and material used for confirming the acquired materials were a scanning electron microscope, JSM 5200, manufactured by JEOL Co., an X-ray diffractometer, manufactured by Rigaku Co., for confirming the surface and matrix structure, inductively coupled plasma, Perkin Elmer Plasma 40, a gas chromatography-mass spectrometer, GC-MASS HP 5988, an IR spectrometer, Biorad FT-60, and a UV-VIS spectrometer, HP diode array 8452A for confirming the composition materials.
EXAMPLE 1
First, γ-lithium aluminate (Johnson & Metthey Co.) was ball-milled in a 500 ml volumetric reactive container having three branches for 72 hours to make the particle size uniform. Then, to assure that the ball-milled γ-lithium aluminate was in the γ-phase, it was reacted at 1,000° C. for six hours.
Next, 300 ml of 2-propanol (GR grade, Merck Co.) from which the water was removed by using a molecular sieve for 24 hours was stirred after being added to 50 g of the γ-lithium aluminate. The stirring was performed with a magnetic stirrer using the apparatus shown in FIG. 8 for about 24 hours.
Then, ammonia gas was introduced to the mixture to reach to a saturated state at a flow rate of 400 cc per minute by passing through calcium chloride, a bath containing sodium chloride and ice and a bath containing acetone and dry ice, using the apparatus shown in FIG. 8. The confirmation of the saturated state was achieved by the backward flow of the solution due to a back pressure within the reaction container.
The reaction was completed by stirring sufficiently for 24 hours, and after saturating with ammonia gas, a small amount of sodium metal (Aldrich Co. spheres of 3-8 mm and 0.1 g each) was added 30-35 times by subdivisions.
After the reactant mixture was centrifuged to obtain precipitates and dried in an oven, the physical property of the powder was examined by an X-ray diffractometer. Then, the powder was processed to manufacture a pellet of 1.5 cm in diameter at a pressure of 8,000 kPa/cm 2 and sintered at 1,000° C. for four hours.
FIG. 2 is a scanning electron microscope (SEM) picture for the pellet manufactured by sintering at 1,000° C. for four hours, which confirms that the pellet is made of γ-lithium aluminate and that the diameters of most particles are in the range of 1-20 μm. About 20% of these γ-lithium aluminate particles were 1-4 μm in diameter and about 80% were 4-20 μm in diameter.
EXAMPLE 2
The pellet was manufactured by the same method as that of Example 1, and the sintering was performed at 900° C. for four hours.
FIG. 3 is a scanning electron microscope (SEM) picture for a pellet manufactured by sintering at 900° C. for four hours according to the above embodiment. It was confirmed that the pellet was made of γ-lithium aluminate and that about 40% of the particles were 1-4 μm in diameter and about 60% were 4-20 μm in diameter.
EXAMPLE 3
The pellet was manufactured by the same method as that of Example 1, and the sintering was performed at 800° C. for four hours.
FIG. 4 is a scanning electron microscope (SEM) picture for a pellet manufactured by sintering at 800° C. for four hours according to the above embodiment. It was confirmed that the pellet was made of γ-lithium aluminate and that about 40% of the particles were 1-4 μm in diameter and about 60% were 4-15 μm in diameter.
EXAMPLE 4
The pellet was manufactured by the same method as that of Example 1, and the sintering was performed at 650° C. for four hours.
FIG. 5 is a scanning electron microscope (SEM) picture for a pellet manufactured by sintering at 650° C. for four hours according to the above embodiment. It was confirmed that the pellet was made of γ-lithium aluminate and that about 40% of the particles were 1-4 μm in diameter and about 60% were 4-10 μm in diameter.
COMPARISON EXAMPLE
A pellet made of a pure γ-lithium aluminate was manufactured in a predetermined shape and then sintered at 1,200° C. for four hours without performing the steps of ball-milling, stirring with 2-propanol, stirring in saturated ammonia gas, adding sodium metal, obtaining precipitates by centrifuging the mixture, and drying the precipitates as in Example 1.
FIG. 1 is a scanning electron microscope (SEM) picture for a pellet manufactured by sintering the pure γ-lithium aluminate at 1,200° C. for four hours. It was confirmed that the pellet was made of γ-lithium aluminate and that almost all particles were 1-4 μm in diameter.
Upon comparison of the SEM pictures of the pellets shown in FIGS. 1 to 5, it is understood that the particle diameters in the pellet manufactured according to the present invention (FIGS. 2 to 5) are far greater than that shown in FIG. 1.
Next, to confirm the components of the pellet as manufactured above, the solution which was saturated with ammonia gas and to which sodium metal was added according to Example 1 was dried to obtain a powder. An X-ray diffraction analysis was performed for the obtained powder and then compared with the pure γ-lithium aluminate.
FIG. 6 shows an X-ray diffraction analysis of the pure γ-lithium aluminate and FIG. 7 shows that of the γ-lithium aluminate manufactured according to the present invention. In the drawings, the peaks marked with a dot correspond to γ-lithium aluminate, the peaks marked with a square correspond to α-Al 2 O 3 , and the peaks marked with an "X" correspond to LiAl 5 O 8 .
In FIG. 6 showing the data by the X-ray diffraction analysis of the pure γ-lithium aluminate, it is confirmed that various materials, such as α-Al 2 O 3 and LiAl 5 O 8 , other than γ-lithium aluminate exist as a mixture, which means that a few oxidants exist in the pure γ-lithium aluminate as impurities. On the other hand, in FIG. 7 showing the data by the X-ray diffraction analysis of the powder obtained by processing γ-lithium aluminate according to the present invention, it is confirmed that only the peaks corresponding to the pure γ-lithium aluminate (marked with " ") are present, which means that the pure γ-lithium aluminate product is obtained by the treatment according to the method of the present invention. In other words, according to the present invention, since the γ-lithium aluminate is pure and has a large diameter, it is possible to manufacture an excellent matrix.
To analyze the data in more detail, it is understood that the γ-lithium aluminate used as a starting material contains about 10% of α-Al 2 O 3 . In the method according to the present invention, the treatment with ammonia gas and the addition of sodium metal allow the α-Al 2 O 3 to melt and to form a metal-alkoxide, i.e., aluminum isopropoxide, which exists as a sol-state until sintering processing, where a mutual combination occurs to produce larger particles.
If a matrix is manufactured with large-diameter particles, the intensity becomes higher. Using three documents (i.e., "Observations and Mechanisms of Fracture in Polycrystalline Alumina," by P. I. Gutshall and G. E. Gross, Eng. Frc. Mech., Vol. 1, pp.463-471, 1969; "Transgranular and Intergranular Fracture in Polycrystalline Alumina," by A. H. Heur, J. Am. Ceram, Soc., pp.510-511, 1969; and "Destruction Driving Change of a PZT Ceramic Body According to Particle Size," Master thesis of the Department of Inorganic Material Engineering Science, Seoul National University, 1988), the following explanation will be made or this particle-size/intensity relationship.
That is to say, since a pellet of small-diameter particles does not have a fractural structure, the internal tension due to the phase change is all concentrated on the boundary portion of the particles, thereby mainly producing the destruction of the particle boundary. On the other hand, since a pellet of large-diameter particles has a fractural structure, the internal tension concentrated on the boundary portion of the particles is decreased, and accordingly, the destruction is decreased.
Also, the destructive aspect of materials is related to the intensity of the materials. Here, if other factors are the same, the case of internal particle destruction has a higher intensity than that for inter-particle destruction. Since the coherence of the particle boundary portion is generally weaker than that of the particle interior, when the destruction of a particle boundary is caused, cracks easily extend along the particle boundaries.
Therefore, it is also understood that the matrix, manufactured of a gamma-lithium aluminate which is pure and has large-diameter particles according to the present invention, has a higher intensity than that manufactured by a conventional method.
In order to confirm that the intensity of the matrix manufactured according to the present invention is higher, an impact experiment has been performed such that same-sized pellets are dropped from a given height and the degrees of breaking or cracking are compared. The result of the experiment, in which the intensities of the pellets are graded by a determination made with the naked eye (with the intensity grades ranging in order from A, the highest, to D, the lowest), is shown in the following Table 1.
TABLE 1______________________________________pellet sintering temperature grade______________________________________Example 1 1,000° C. AExample 2 900° C. BExample 3 800° C. CExample 4 650° C. DComparison Example 1,200° C. D______________________________________
From the above table, it is confirmed that the pellet manufactured according to the present invention has a higher intensity than the conventional one and that the higher the sintering temperature is, the higher the intensity is. Also, although a pellet is manufactured by the method according to the present invention, if the sintering temperature is reduced to 650° C. or below, a high-intensity pellet cannot be obtained, which implies that sintering at a temperature which is too low cannot produce an excellent effect. However, since the matrix according to the present invention, compared with the conventional method, can be manufactured at relatively low temperatures, e.g., 1,000° C., 900° C., 800° C. or 650° C., the manufacturing cost is considerably reduced. Therefore, the matrix for an MCFC manufactured by the method according to the present invention, which has excellent intensity and quality, is very useful.
While the present invention has been particularly shown and described with reference to particular embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be effected therein without departing from the spirit and scope of the invention as defined by the appended claims. | A manufacturing method of a matrix for a molten carbonate fuel cell, including the steps of saturating gamma-lithium aluminate with ammonia gas and adding sodium metal, can manufacture large-diameter gamma-lithium aluminate particles at a low temperature. The matrix, having gamma-lithium aluminate particles with diameters of 4-10 μm as the main component, has high intensity. | 8 |
This is a continuation of application Ser. No. 07/703,872 filed May 22, 1991, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to apparatus for performing friction bonding operations. In particular, it concerns apparatus for performing a non-rotational frictional bonding operation.
2. Description of the Prior Art
An embodiment of the invention as described in detail hereinafter is particularly concerned with the manufacture or repair of a bladed disc, sometimes known as a BLISK. A bladed disc comprises a disc or wheel on the periphery of which there is attached or carried a multiplicity of blades. In a conventional rotor assembly the blades are attached to a disc or wheel by interlocking root fixtures. In bladed discs the blades are either formed integrally with the disc or are non-dismountably attached thereto. The present invention finds application for the manufacture or repair of assemblies in which the inter-blade spacing is very close and the blades may also be small. Such an example may be in the repair of a high pressure compressor bladed disc rotor.
Small blades are also relatively fragile and may be easily damaged during a friction bonding operation which involves very large forces to produce the required frictional heating effects. Therefore, it is preferred to work with a blade blank or preform and to finish the blade to its final shape after bonding
SUMMARY OF THE INVENTION
According to the invention in its broadest aspect a
blade or blade preform is attached to the rim of a bladed disc in a non-rotational friction bonding operation.
According to one aspect of the present invention apparatus for performing a non-rotational friction bonding operation comprises moveable clamping means having jaws with opposing faces adapted to positively engage opposite sides of a blade member during the bonding operation to impart thereto the necessary bonding forces. Preferably the clamping means comprises a generally U-shaped frame member having a pair of limbs adapted to engage the member to be bonded.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention and how it may be carried into practice will now be described in greater detail with reference by way of example only to the accompanying drawings, in which:
FIG. 1 shows a schematic diagram of a blade replacement operation viewed in a radial direction,
FIG. 2 shows a view in the direction of arrows AA in FIG. 1, and
FIGS. 2A-2C show the gripping process wherein the jaw pieces are drawn up the channel, thus clamping the blade member.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings, in which like parts have been given like references, the example illustrated involves the repair of a bladed disc, or BLISK, using a linear friction bonding operation.
A blade preform or blank 2 is bonded to the periphery of disc 4, a fragment of which is shown in the drawing, at a predetermined location. FIG. 1 shows such a blade preform 2 clamped between jaw pieces 6,8 of a clamping means at the start of a bonding operation.
The preform 2 consists of solid block of metal of appropriate shape and size. At the leading and trailing edge regions 10,12 a considerable amount of sacrificial metal is left by which the jaw pieces 6,8 grip the preform 2. The edges are formed with angled faces for engagement by the jaw pieces. In FIG. 1 the radially outer ends of preforms 2 are shown hatched for easier reference. After finishing of the blade airfoil shape these end faces form the blade tip faces.
The clamping means comprises the jaw pieces 6,8 set in the inner faces of the limbs 14,16 of a U-shaped frame 18. The jaw pieces 6,8 are moveable and located in channels 24,26 in the inner faces of limbs 14,16 respectively. The jaw pieces 6,8 have angled grip faces, V-shaped in plan to grip the complementary angled faces on the leading and trailing edges of the preform 2. At the apex of the angled faces relatively deep grooves 20,22 are cut into the jaw pieces to provide the angled faces with a degree of resilience in gripping the preform.
The jaw pieces 6,8 are located, as mentioned above, in channels 24,26 formed in the inner faces of the frame limbs 14,16. The jaw pieces are slideable longitudinally in the channels. Towards the distal end of each limb the base of the channel and the abutting face of the respective jaw pieces are angled obliquely with respect to the longitudinal direction of movement. These angled surfaces converge towards the upper or closed part of the clamping frame so that by drawing the jaw pieces 6,8 upwardly in FIG. 2, in the direction of arrows 28,30, their grip on the blade preform 2 is tightened (see FIGS. 2A-2C).
The jaw pieces 6,8 may extend longitudinally in the directions of arrows 28,30 as shown in the drawings or may be attached to tensile members. The remote ends of the jaw pieces extensions or the tensile members, are connected to hydraulic tension means (57,58) which is energised to draw the jaw pieces upwardly to grip the preform. Clearly the clamping means may be released from the preform after a bonding operation by relaxing the tensioning force in the jaw pieces.
The moveable clamping frame 18 also carries a ram 32 which bears against the tip face of blade preform 2 and applies the required upset force to effect bonding at the end of the frictional heating phase of the operation.
It is preferred to replace a blade belonging to a BLISK rotor using this method as follows. First, the old or damaged blade is removed just above the peripheral surface 34 of the disc rim leaving a stub portion 36. The upper surface 38 of this stub is made flat and the foot of the replacement blade preform is bonded to it. The preform 2 is at least longer than the stub 36 due to the presence of the sacrificial gripping regions 10 and 2. It may be slightly wider also. The lower margin of the preform is therefore preferably chamfered so that lower surface 40 matches upper surface 38 of stub 36.
The surface 40 may be made shaped for better control of the frictional heating phase.
During the frictional heating phase of a bonding operation the clamping means containing the preform 2 is moved back and forth (arrows). Several directions of movement are available in the plane of the joint. The amplitude of this movement is small, generally only a few millimetres is required and is at a low frequency. For maximum rigidity the jaws of the clamping means are wider than the inter-blade spacing. Because of the resulting overlap the distance between the jaws must provide sufficient clearance for the chosen motion. The extra distance is easily provided for in the edge regions 10,12 on the preform 2. Thus, during the whole of a bonding operation clearance is maintained between the clamping means and adjacent blade tips.
For maximum lateral rigidity the jaw pieces are preferably flush with the face of the clamping means. Where the blades are closely spaced the clearance distance must be maintained to avoid blade damage. It follows, therefore, that the edge regions 10,12 of a blade preform which are intended to be engaged by the clamping means must be removed after bonding and before another blade may be bonded at an adjacent location. Alternatively, a number of blade preforms may be bonded sequentially at locations sufficiently far apart. In the illustrated case the minimum spacing is alternate locations. A whole BLISK could be manufactured, if desired, in this way by bonding blades at, say, alternate locations in a first operation, subsequently removing surplus metal and then bonding the remaining blades in a further operation.
Finally, after the bonding operation, or operations if more than one blade preform is attached, the preform or preforms are finished to final blade airfoil shape by a further manufacturing operation. Surplus metal including that upset during bonding is removed at this stage, for example, by electro-chemical machining. | Apparatus and a method for attaching individual blades to a disc rotor of a BLISK is described. Blade blanks or preforms are gripped between adjustable jaws of a rigid frame member of a linear friction bonding machine, and are attached in a non-rotational friction bonding operation. Blade preforms may be finished to final airfoil shape in a further operation after attachment. The technique is suitable for repair work or original manufacture. | 8 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a continuation of U.S. Non-Provisional Application No. 12/274,814 filed Nov. 20, 2008, still pending, which claims the benefit of prior U.S. Provisional Application No. 61/003,748, filed Nov. 20, 2007.
FIELD OF THE INVENTION
[0002] The present invention relates generally to self-standing riser systems used during energy exploration and production, and in a particular though non-limiting embodiment, to a system useful for deploying self-standing risers and associated buoyancy devices in a variety of operating conditions.
BACKGROUND OF THE INVENTION
[0003] Over the past decade, there has been an increasing worldwide demand for oil and gas production. At present, however, oil and gas supply continues to lag far behind demand, a situation which has at times contributed significantly to worldwide economic difficulties and could well present a major concern for many years to come.
[0004] In an effort to balance supply and demand, companies and governmental entities have begun to explore and develop relatively marginal fields in the deeper offshore waters of the Gulf of Mexico, West Africa and Brazil. However, due to high construction costs and limited manufacturing facilities, only a small number of mobile offshore drilling units (MODUs) are being manufactured each year, thereby resulting in escalating “per day” unit costs and a shortage of associated offshore drilling, completion and workover equipment.
[0005] Moreover, even though the cost differential between drilling operations and completion or workover operations is relatively modest (since MODUs usually perform all of these functions during a typical operation), most such projects are still inefficient, because a MODU actively performing one function (e.g., drilling) is generally not able to accomplish any other functions (e.g., completion or workover).
[0006] In other applications by this inventor, it has been shown that a self-standing riser system can be safely and reliably installed in communication with a well head or production tree. Such risers by design are self-supporting, and provide all of the necessary risers, casing, buoyancy chambers, etc., required for exploration and production and of oil, gas and other hydrocarbons. Self-standing risers also provide the requisite safety features required to ensure that the produced hydrocarbons do not escape from the system out into surrounding waters. For example, self-standing riser systems fully support both surface-based and semi-submersible platform interfaces, blow-out preventers, production trees, and other common exploration and production installations.
[0007] Known self-standing riser systems require either a number of different surface vessels or a MODU for installation, due to the size and weight of riser stacks, drilling pipe, buoyancy devices, etc. For many installations, expensive hull and deck modifications also have to be made. Accordingly, few improvements in associated per-day costs have been realized.
[0008] There is, therefore, a need for a more cost-effective method of installing self-standing riser systems, which does not require the use of MODUs.
SUMMARY OF THE INVENTION
[0009] A water-borne vessel for deploying a self-standing riser system is provided, wherein the vessel hull is configured to receive, transfer and deploy components of a self-standing riser system. The vessel hull includes at least a landing platform, a component transfer means, and a deployment platform suitable for deploying the riser components into associated surrounding waters. Various means of assisting the process whereby self-standing riser components are loaded onto the vessel and stored; transferred from receiving to deployment platforms; and deployed from the vessel into surrounding waters are also considered.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1A is a side view of a self-standing riser deployment vessel, according to example embodiments.
[0011] FIG. 1B is a schematic diagram depicting the submersion of a self-standing riser system, according to example embodiments.
[0012] FIG. 1C is a schematic diagram of a deployment vessel positioning a completed self-standing riser system, according to example embodiments.
[0013] FIG. 1D is a schematic diagram of a deployment vessel releasing from a completed self-standing riser system, according to example embodiments
[0014] FIG. 2A is a side view of a self-standing riser system deployment vessel, according to example embodiments.
[0015] FIG. 2B is top view of a self-standing riser system vessel equipped with a buoyancy device loading bay, according to example embodiments.
[0016] FIG. 2C is a schematic diagram depicting a buoyancy device being lowered into a buoyancy device loading bay, according to example embodiments.
[0017] FIG. 2D is a schematic diagram of a deployment vessel beginning its release of a deployed buoyancy device stack, according to example embodiments.
[0018] FIG. 2E is a schematic of a deployment vessel having released its load, and leaving the site prior to commencement of drilling operations.
DETAILED DESCRIPTION
[0019] The description that follows includes exemplary systems, methods, and techniques that embody various aspects of the presently inventive subject matter. However, it will be readily understood by those of skill in the pertinent arts that the described embodiments may be practiced without one or more of these specific details. In other instances, well-known manufacturing equipment, protocols, structures and techniques have not been shown in detail in order to avoid obfuscation in the description.
[0020] Referring now to FIG. 1A , an example embodiment of a self-standing riser deployment vessel 6 is depicted, comprising a plurality of buoyancy devices 2 temporarily attached to the bottom of the hull. In exemplary embodiments, deployment vessel 6 is a workboat, anchor handling boat, or any other available vessel of suitable size and configuration; the lengths of such vessels might range, for example, from around 150 ft. to around 300 ft., though these size estimates should not be deemed as limitative.
[0021] Other embodiments of deployment vessel 6 comprise enough deck and storage space to carry associated riser tubing 4 , and additional buoyancy devices 2 . Still further embodiments employ dynamic positioning equipment (e.g., a spar), which facilitate efficient and reliable riser stack deployment and installation on the sea floor.
[0022] In one embodiment, an entire string of risers is assembled with one or more buoyancy devices interspersed as needed in order to provide sufficient buoyancy for the entire system. The string is then deployed as a continuous structure and lowered to the sea floor in a controlled manner. The top of the string is then secured and lifted so that it can be moved over the drilling site and attached to the well. In other embodiments, the system is deployed in a piecemeal fashion, with sections of a desired length being individually deployed and mechanically joined as the assembly is completed.
[0023] In the example embodiment illustrated in FIG. 1A , deployment vessel 6 further comprises a hoisting frame 3 disposed near a moon pool 5 . The hoisting frame permits riser 4 stored within the vessel to be loaded and lowered or held in position. In various embodiments, the lowering, raising and holding of riser 4 is facilitated using conveyor belts, chains, rollers, etc. In one example embodiment, riser 4 is transferred from a storage container towards the moon pool 5 using a conveyor belt, and subsequently connected to a fastening device affixed to hoisting frame 3 . The riser can then be deployed or held in a desired position in a safe and reliable manner.
[0024] Consistent with the example deployment vessel 6 illustrated in FIG. 1A , further embodiments also comprise loading mechanisms (e.g., frames, rails, etc.) used to load, guide and control the buoyancy devices 2 . FIG. 1A , for example, depicts two buoyancy devices 2 disposed in mechanical communication with the bottom of the hull of the deployment vessel 6 . The buoyancy devices 2 are affixed to a carrying frame 1 configured to reliably accommodate large, heavy loads. Carrying frame requirements will vary by project, but each such device should, at minimum, be capable of supporting the weight of one or more buoyancy devices. Electric, hydraulic or pneumatic lifts can be used to raise and lower the buoyancy devices, and ropes, chains, and tension lines reeled out from strategically placed winches can assist in the fine control necessary to ensure safe and controlled deployment of the buoyancy devices.
[0025] In some embodiments, each of said buoyancy devices 2 further comprises a connector 14 (i.e., a flange or receptive housing, etc.) that allows for attachment of additional buoyancy devices 2 or riser assemblies 4 .
[0026] In the example embodiment depicted in FIG. 1B , each of the buoyancy devices further admit to the passing of riser 4 through a void space in the buoyancy devices by means of a hoisting frame 3 , so that the riser 4 can subsequently be attached to a subsurface wellhead 8 installed atop a well bore 9 . A flanged member 18 can be used to help capture descending riser and assist in connection of the riser to the wellhead.
[0027] In the example embodiment illustrated in FIG. 1C , deployment vessel 6 is used to lower a fully assembled self-standing riser system into position for attachment with wellhead 8 . Guide frame 1 assists in the controlled deployment of the riser near the surface, and a flanged member 14 assists in capture of the lowered riser. In other embodiments, deployment vessel 6 utilizes dynamic positioning equipment (or alternatively, light equipment such as ropes, chains, winch lines, etc.) to lower, raise and support the riser stack as it is position above the wellhead. Further embodiments utilize buoyancy devices to tension the stack as deployment is carried out, and to dynamically position the riser between the vessel and the well.
[0028] As seen in FIG. 1D , once the self-standing riser system is deployed and attached to the well, the surface vessel releases its hold and the vessel can be used for other operations on a cost-effective basis. In some embodiments, the vessel deploys the self-standing riser and leaves the site so that other vessels (e.g., vessels with testing packages, separators, or even MODUs when one becomes available) can interface with the system and initiate completion, testing or workover operations.
[0029] Referring now to FIG. 2A , a side view of a deployment vessel is illustrated, comprising a plurality of buoyancy devices 2 and a reliable means for deployment thereof. Some embodiments comprise one or more of a loading crane, a hoisting frame, buoyancy device transmission and positioning means 5 , etc., disposed near a moon pool.
[0030] As seen in FIG. 2B , it may be convenient that the moon pool is formed at the aft end of the vessel. In an especially novel approach, the aft end is open, and the moon pool has only three sides 6 , so that greater flexibility in position is achieved. In still further embodiments, the buoyancy devices 2 are loaded onto the deployment vessel from a neighboring service vessel, whereafter operations are carried out as described above.
[0031] In the example embodiment depicted in FIG. 2A , a plurality of buoyancy devices 2 are loaded onto the deployment vessel from a neighboring vessel, positioned for deployment from the deployment vessel by a transmission means 5 , and then deployed into a body of water in a safe and controlled fashion that ensures efficient operations and maintenance of the buoyancy devices' structural integrity.
[0032] In some embodiments, a neighboring crane is used to lower the buoyancy devices onto a deployment vessel landing platform, as depicted in FIG. 2A . The landing platform can be either flooded (in the event the devices are intended for immediate deployment), or dry (in the deployment is intended for a later time, or if access is needed so as to permit outfitting or maintenance). If the landing platform is dry, intake ports are provided so that it can later be flooded, allowing easier transportation and deployment of the devices at or near the drilling site (see, for example, FIG. 2C ). Such embodiments would likely utilize winches, fastening mechanisms, etc., to secure and facilitate safe and reliable control of the devices. The deployment vessel can then transport and deploy the devices as described above.
[0033] In the example embodiment depicted in FIG. 2C , a barge or other transport vessel is used to transfer additional buoyancy devices to the landing platform of a deployment vessel by means of a rope, chain, winch line, etc. In one particular embodiment, the buoyancy devices are moved via roller tracks toward an overhead gantry, hoisted by a crane or other hoisting device, and lowered into the deployment pool.
[0034] In the example embodiment depicted in FIG. 2D , the buoyancy devices have been landed from a service vessel and lowered into the water. The devices are then towed in by a second deployment vessel and attached to its hull via winches, hooks, fastening mechanisms, etc., disposed in mechanical communication with the second deployment vessel. In FIG. 2E , the second deployment vessel has captured and secured the devices, and the service vessel has released its line. The service vessel can then repeat the process until the desired number of buoyancy devices has been transferred to a desired number of deployment vessels.
[0035] The foregoing specification is provided for illustrative purposes only, and is not intended to describe all possible aspects of the present invention. Moreover, while the invention has been shown and described in detail with respect to several exemplary embodiments, those of ordinary skill in the art will appreciate that minor changes to the description, and various other modifications, omissions and additions may also be made without departing from the spirit or scope thereof. | A water-borne vessel for deploying a self-standing riser system is provided, wherein the vessel hull is configured to receive, transfer and deploy components of a self-standing riser system. The vessel hull includes at least a landing platform, a component transfer means, and a deployment platform suitable for deploying the riser components into associated surrounding waters. Various means of assisting the process whereby self-standing riser components are loaded onto the vessel and stored; transferred from receiving to deployment platforms; and deployed from the vessel into surrounding waters are also considered. | 4 |
RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Patent Application No. 60/858,208 filed on Nov. 10, 2006.
FIELD OF THE INVENTION
The apparatus and method of the present invention relate in general to wellbore operations and more specifically to an apparatus and method for jarring of a stuck wireline deployed tool used in downhole wellbores.
BACKGROUND
When logging wells for the discovery of hydrocarbons wellbore tools are often deployed on cable, including wireline, slick line, and electric wireline. A common problem that occurs in these operations is that the tool gets stuck in the wellbore by running into a restriction in the wellbore called a “squeeze”, an area where the wellbore has collapsed either from formation pressure forcing the well walls to collapse, or from debris sluffing off the well walls causing blockage called a “bridge”. The tool can be freed by jarring the tool in an upward direction because there is no debris or restriction above the tool. When the tool becomes free it can be worked up and down to get the tool through the restriction, this is called “spudding”. If the spudding operation is successful, the tool can pass the restriction and continue to run downhole to complete the of the well.
When the logging is completed, the tool can become stuck when it is being pulled out of the wellbore. Sometimes the tool can be jarred upward pulling it through the restriction and sometimes it does not come free because the squeeze or bridge is too large or heavy.
If the tool becomes permanently stuck the options are to electrically burn off the weak point of the tool or pull off the weak point of the tool and do a fishing trip to retrieve the lost tool. Prior to pulling off or burning the weak point if a downward force could be applied to the tool to move it down out of the restriction the tool could be worked up and down to spud the tool up through the restriction the same way spudding the tool to get it through the restriction while running downhole.
Therefore, it is a desire of the present invention to provide a method and apparatus for freeing a wireline deployed tool by jarring in a downward direction.
SUMMARY OF THE INVENTION
An example of a wellbore jar includes a first sub-assembly with an upper member secured the lower end of a wireline, a second sub-assembly positioned lower than the first sub-assembly and attached to the first sub-assembly. The second sub-assembly also includes a first housing, a shaft and a first spring, wherein the shaft and the spring are inside the first housing. The wellbore jar also includes a third sub-assembly including a second housing and second spring arrangement, in communication with the second sub-assembly. The wellbore assembly also includes a fourth sub-assembly attached to the third sub-assembly and also attached to a down hole tool. The fourth sub-assembly further including a third housing, and a third spring; wherein the first, second and third string are capable of storing compressive energy. The wellbore assembly also includes an actuator for releasing the stored energy in the first, second and third springs downward onto the tool.
An example of a method of dislodging a stuck tool downhole is disclosed. The method includes the steps of providing a jarring apparatus above the stuck tool. The jarring apparatus has a first, second, third and fourth sub-assembly in communication with each other. The upper end of the first sub-assembly is attached to a wireline, which imparts an upward force on the first, second and third sub-assemblies by pulling the wireline towards the surface of the well. Compressing a first, and second spring located in the second and third sub-assemblies then releasing the compressed force stored within the second and third sub-assembly downward against the fourth sub-assembly attached to the stuck tool sufficient to dislodge the stuck tool, with an imparting force on the tool attached to the upper end of the first sub-assembly.
Another example of a wellbore jar for dislodging tools downhole is disclosed. The wellbore jar includes: a first attachment means for attaching to the upper end of the apparatus to a wireline cable. There is also a second attachment means for attaching to the upper end of the tool to the lower end of the apparatus and a spring mechanism within the apparatus for storing compressional force as the length of wireline above the apparatus applies upward force on the apparatus. Also present is an actuating means for rapidly releasing the stored compressional force downward onto the tool lodged downhole.
The foregoing has outlined some of the features and technical advantages of the present invention in order that a detailed description of an example of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and other features and aspects of the wellbore jar will be best understood with reference to the following detailed description of a specific embodiments of the invention, when read in conjunction with the accompanying drawings, wherein:
FIGS. 1A-1D illustrate an example of the apparatus in operation;
FIG. 2A is a partial cut away view of an example of a first sub-assembly of an apparatus in isolation;
FIG. 2B is a partial cut away view of an example of a second sub-assembly of an apparatus in isolation;
FIG. 2C is a partial cut away view of an example of a third sub-assembly of an apparatus in isolation;
FIG. 2D is a partial cut away view of an example of a fourth sub-assembly of an apparatus in isolation; and
FIG. 3 is a partial cut away view of an example of the apparatus as it is compressed.
DETAILED DESCRIPTION
Refer now to the drawings wherein depicted elements are not necessarily shown to scale and wherein like or similar elements are designated by the same reference numeral through the several views.
As used herein, the terms “up” and “down”; “upper” and “lower”; “uphole” and “downhole”; and other like terms indicating relative positions to a given point or element are utilized to more clearly describe some elements of the embodiments of the invention. Commonly, the terms “up,” “upper,” “uphole,” and other like terms are meant to indicate a position that is closer to the surface along the linear distance of the borehole. It is noted that through the use of directional drilling, a wellbore may not extend straight up and down. Thus these terms describe relative positions along the wellbore.
FIG. 1A provides an example of the present invention. Apparatus 10 includes four principal sub-assemblies attached to a tool 11 located in a wellbore 18 . First sub-assembly 12 includes an upper member 14 secured to the lower end of wireline 16 . Second sub-assembly 20 is lower than first sub-assembly 12 and is attached to first sub-assembly 12 . Third sub-assembly 24 is a tube and spring arrangement, in communication with second sub-assembly 20 and the fourth sub-assembly 25 . Fourth sub-assembly 25 is attached to third sub-assembly 24 and is also attached to the down hole tool. Wellbore 18 , as illustrated, is free of any squeezes or impediments.
FIG. 1B illustrates tool 11 stuck below obstruction 26 . An end user located topside to the wellbore 18 , would know of the blockage caused by obstruction 26 as the wireline 16 would no longer be moved upward in the wellbore. Apparatus 10 will then be fully extended showing the intersections between sub-assemblies 12 , 20 , and 24 . During this time none of the springs in sub-assemblies 12 , 20 , and 24 are constricted and the springs do not store any spring energy. (See FIG. 2A-D for spring locations).
FIG. 1C illustrates the tension on wireline 16 being removed, whereby the weight of apparatus 10 will cause apparatus 10 to contract due to gravity. When apparatus 10 is contracted the springs located in sub-assemblies 12 , 20 and 24 will contract storing compression energy. In the fully contracted state, apparatus 10 is primed and its internal springs tightened ( FIGS. 2A-D ). The energy stored in the springs is so great that third sub-assembly 24 will have its internal spring activate.
FIG. 1D provides an example of the present invention as shown in FIG. 1C except that in FIG. 1D third sub-assembly 24 has activated, therein dislodging fourth sub-assembly 25 from obstruction 26 due to a downward force. The weight of apparatus 10 must be greater than force holding apparatus 10 in obstruction 26 , otherwise the discharge of the spring 54 in third sub-assembly 24 will cause the three sub-assemblies 12 , 20 and 24 above obstruction 26 to move upward instead of forcing fourth sub-assembly 25 downward.
FIGS. 2A-D illustrate the sub-assemblies that make up an example of apparatus 10 .
FIG. 2A provides an example of first sub-assembly 12 in isolation. First sub-assembly 12 includes of shaft member 28 , cap 30 , housing 32 , spring 34 , threaded tube 36 , split thread collar 38 and shaft cap 40 . Cap 30 is attached to housing 32 such that a portion of cap 30 is housed in housing 32 . The portion of cap 30 that is interior to housing 32 is threadably attached to threaded tube 36 . Also threadably attached to threaded tube 36 is shaft member 28 . A portion of shaft member 28 is inside of housing 32 and a portion is exterior to housing 32 . The interior portion of shaft member 28 is positioned within spring 34 . The portion of housing 32 that is opposite to cap 30 is threaded and joined with split thread collar 38 . Shaft member 28 is also fitted with a shaft cap 40 which is opposite housing 32 . Cap 30 is also constructed to attach to the lower end of wireline 16 . Shaft member 28 of first sub-assembly 12 can be pulled upward to compress an internal spring 34 .
FIG. 2B is a cross sectional view of the second sub-assembly 20 in isolation. Second sub-assembly 20 includes tube 42 , housing 44 , spring 46 , cap 48 , tube 50 , and housing 52 . Tube 42 is constructed so as to have shaft member 28 slideably move within housing 44 . In effect, tube 42 acts as a piston wall with shaft member 28 capable of movement inside the piston. Tube 42 is threaded and attached to housing 44 . Interior to housing 44 is another spring 46 which is constructed to fit around shaft member 28 . Spring 46 is also buttressed with cap 48 with an opening. Cap 48 acts as a backstop for spring 46 , but allows for movement of shaft member 28 through the opening. Also threadably attached to housing 44 is housing 52 . Inside of housing 52 and threadably attached to housing 52 is tube 50 .
FIG. 2C is a cross sectional view of third sub-assembly 24 in isolation. Third sub-assembly 24 includes a spring 54 , hollow cap 56 , and tube 58 . Spring 54 is located inside of hollow cap 56 , and tube 58 . Tube 58 is threadably joined opposite hollow cap 56 with an additional hollow cap 59 such that hollow cap 59 is a backstop for spring 54 . Although not illustrated, the use of latches associated with tube 58 of third sub-assembly 24 could be implemented to ensure that the springs 34 and 46 remain coiled prior to striking third sub-assembly 24 and releasing the compressed spring energy.
FIG. 2D is a cross sectional view of fourth sub-assembly 25 in isolation. Fourth sub-assembly 25 includes a tube 60 , a housing 62 , and a cap 64 . Tube 60 is designed to accommodate tube 58 of third sub-assembly 24 such tube 58 can slide into tube 60 similar to a piston. Fourth sub-assembly 25 also contains cap 64 which can act as the connection point of the lower end of apparatus 10 that connects to the upper end of tool 11 .
FIG. 3 is a cross sectional view of an example of apparatus 10 of the present invention, shown in a contracted or cocked position. When the tension on wireline 16 is released first sub-assembly 12 , spring 34 between sub-assemblies 12 and 20 is compressed. The weight of sub-assemblies 12 and 20 compress spring 54 between sub-assemblies 20 and 24 . The impact of sub-assemblies 12 and 20 on sub-assembly 24 is sufficient to act as an actuator and to cause spring 54 to expend its stored spring energy and force fourth sub-assembly 25 downward, thereby dislodging fourth sub-assembly 25 from the obstruction 26 . Housings 32 and 62 are constructed to have lips 32 a and 62 a respectively, which extend into the interior of the housings 32 and 62 . Tubes 42 and 60 are constructed to have flanges 42 a and 60 a respectively which are designed to engage the lips 32 a and 62 a respectively so that tubes 42 and 60 will not extend past lips 32 a and 62 a when apparatus 10 is fully extended ( FIG. 1B ).
From the foregoing detailed description of specific examples of the apparatus, it should be apparent that a wellbore drilling system and method that is novel has been disclosed. Although specific examples have been disclosed herein in some detail, this has been done solely for the purposes of describing various features and aspects of the invention, and is not intended to be limiting with respect to the scope of the invention. It is contemplated that various substitutions, alterations, and/or modifications, including but not limited to those implementation variations which may have been suggested herein, may be made to the disclosed examples without departing from the spirit and scope of the invention as defined by the appended claims which follow. | An example of an apparatus for jarring a wellbore tool from an obstruction includes four sub-assemblies in communication with three springs such that the springs may be compressed forcing the subassemblies to become adjacent to one another. When the springs are actuated, the sub-assembly units spring apart from one another force dislodging the lower most sub-assembly component from the obstruction. | 4 |
BACKGROUND OF THE INVENTION
The present invention relates to an improved process for producing highly pure aromatic carboxylic acid from an impure solid acid product, and, more particularly, to a process improvement whereby the solid acid product can be efficiently dissolved in a suitable solvent at relatively low temperatures despite the presence of solid lumps.
In typical commercial processes for producing highly pure aromatic carboxylic acids, and particularly isophthalic and terephthalic acid, a rather insoluble, impure acid is first produced and recovered from an oxidation process. In the oxidation process, which involves catalytic air oxidation of paraxylene in acetic acid solvent in the case of terephthalic acid, the impure acid, usually in the form of solid crystals, is conveyed from a dryer to a holding silo before further processing in a usually separate purification stage to remove impurities. In the purification stage of such a process, crude, i.e., impure, acid crystals are slurried in water, recycled mother liquor or other suitable solvent, and the resulting slurry is pumped through a series of preheaters to raise the slurry temperature and thereby dissolve the slurry particles. The resulting solution is then subjected to hydrogenation at elevated temperature typically in the range of 280°-283° C. under liquid phase conditions in the presence of a Group VIII noble metal hydrogenation catalyst. The purified acid is recovered by crystallizing the acid from the hydrogen treated solution. The principal impurities, which are p-toluic acid (m.p. 180° C.; b.p. 275° C.) derived from the compound 4 -carboxybenzaldehyde (4-CBA) (m.p. 258° C.; b.p. sublimes) and unidentified color bodies, along with some other organic components, such as benzoic acid (m.p. 122.5° C.; b.p. 249° C.) and some residual terephthalic acid, (in the case of terephthalic acid) remain dissolved in the solution.
Depending on the conditions under which the crude acid is dried, its moisture content, and the time during which the acid is held in the holding silo before entering the purification stage, significant lumping of the solid product can occur. These lumps can be as large as 10 cm in average diameter, and, in turn, they can be very difficult to process, can clog and even damage valves and conveying equipment, and can be very difficult to efficiently dissolve in water and other solvents, especially at relatively low initial temperatures, i.e., below about 100° C., for further processing. The present invention provides a method for handling these lumps in the context of a process for producing highly pure aromatic carboxylic acid from a crude crystalline starting material.
SUMMARY OF THE INVENTION
The present invention is an improvement in a process for producing a highly pure aromatic carboxylic acid crystals from an impure solid acid product which includes the steps of:
(a) dissolving the impure solid product in a solvent at elevated temperature to form a solution;
(b) hydrogenating the solution in the presence of a hydrogenation catalyst;
(c) optionally separating the solution from the catalyst; and
(d) cooling the solution to precipitate pure aromatic carboxylic acid crystals. The improvement comprises dissolving the impure solid product in the solvent by metering the impure solid product from its storage silo through an appropriate exit nozzle into a holding tank containing the solvent in response to a feedback signal. It is thereby possible to form an intermediate slurry of impure acid crystals at a relatively low temperature in the range of from 90° C. to 100° C. and at a concentration in a range of from 28% w/w up to 30% w/w while continuously agitating the slurry as it is formed. The slurry is then removed, i.e., pumped, from the holding tank while undesirably large lumps of yet undissolved solid product, i.e., particles having an average size greater than from 24 mm to 28mm, are retained in the holding tank. The density of the slurry is continuously measured at a location downstream from the holding tank, and that measurement is then converted into a feedback signal which is communicated to the metering device to control the rate at which solid impure product and solvent are introduced into the holding tank. Simultaneously as the slurry is being pumped from the holding tank or thereafter via one or via several intermediate steps, the slurry is heated to an appropriately high processing temperature of about 283° C. and the pressure of the slurry is raised to an appropriate level at which substantially all of the acid particles have dissolved prior to hydrogenation and purification.
The process of the present invention can be operated on a continuous basis or batch-wise, and, in a preferred embodiment of the invention, metering of the solid impure product from its storage silo into the slurry holding tank is accomplished using a motor-actuated rotary valve having a control device which is responsive to the feedback signal.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a simplified schematic diagram of a process improvement according to the invention.
DETAILED DESCRIPTION
The present invention is particularly applicable to a process for producing highly pure aromatic carboxylic acid crystals from a crude solid acid product. The aromatic carboxylic acids which are of most commercial interest are isophthalic acid and terephthalic acid, although the process is applicable for handling any impure solid acid product which undergoes a similar hydrogenation purification in solution.
A typical purification process to which the invention applies includes the steps of:
(a) dissolving the impure solid product in a solvent at elevated temperature to form a solution;
(b) hydrogenating the solution in the presence of a hydrogenation catalyst;
(c) optionally separating the solution from the catalyst; and
(d) cooling the solution to precipitate pure aromatic carboxylic acid crystals. In the case of isophthalic acid and terephthalic acid, water, which may include recycled aqueous mother liquor, is the preferred solvent, and it will be referred to in the discussion which follows to illustrate the invention.
The improvement according to the invention comprises dissolving the impure solid product in the solvent, e.g., water, by:
(e) metering the impure solid product into a holding tank containing said solvent using a motor actuated metering device in response to a feedback signal to thereby form a slurry of impure acid crystals at a relatively low temperature in the range of from 90° C. to 100° C. and having a concentration in the range of from 28% w/w to 30% w/w while continuously agitating the slurry as it is formed;
(f) removing the slurry from the holding tank through a retaining screen whereby those particles of yet undissolved solid product which have a particle size greater than the openings in the screen are retained in the holding tank;
(g) measuring the density of the slurry downstream from the holding tank and converting the density measurement to a feedback signal;
(h) communicating the feedback signal to the metering device in step (e); and simultaneously therewith or thereafter
(i) heating the slurry.
In practice on a commercial scale, a crude isophthalic or terephthalic acid is recovered from an oxidation process as a crystalline powder and conveyed to a storage silo to await further processing. The storage silo and related processing equipment, tanks, etc. and piping utilized in the purification process which follows are typically fabricated from a stainless steel or other alloy that can resist corrosion and avoid contamination of the reactants. The solid crystalline powder, in addition to chemical impurities formed during the oxidation reaction, may also contain residual solvent from earlier processing and washing, and it may have some concentration of moisture, all of which can contribute to a tendency for the crystal particles to cling together and form massive, hard lumps over time.
Purifying the crude, i.e., impure, acid product requires first dissolving the crystalline product in a solvent, such as, for example, demineralized or recycled water (i.e., mother liquor), or a mixture of the two. The rate at which the acid crystals can dissolve can be influenced by numerous factors, such as, particle (lump) size, concentration, temperature, pressure and agitation. For ease of processing it has been found most convenient to first form an aqueous slurry of the crude acid at a relatively low temperature in the range of from 90° C. -100° C. in an intermediate “slurry holding tank” which is equipped with an agitator for continuously mixing the slurry as it forms and thereby enhancing the rate of dissolution.
Referring now to FIG. 1, crude acid crystals are metered from storage silo 10 into slurry holding tank 11 through a one of two possible discharge nozzles or lines. Illustrated in FIG. 1 is a primary discharge line 12 which comes directly off the conical base of the storage silo and secondary discharge line 12 A which comes off the side of the conical section as shown. Each discharge line is equipped with a motor-actuated metering device, which, in a preferred embodiment of the invention, is a motor-actuated rotary valve 13 of suitable diameter, e.g. not less than about 20 cm in diameter. The speed of rotary valve 13 is controlled by a slurry density controller. The controller output is via an invertor to control the speed of the rotary valve drive motor in the range of from 0 to 22 rpm.
Storage silo 10 is typically located directly above slurry holding tank 11 as shown greatly simplified in the figure, and slurry holding tank 11 is equipped with an agitator 14 for continuously agitating the slurry as it is formed. A vertically positioned single impeller axial downflow agitator 14 is shown which typically operates at about 68 rpm. However, any suitable means of agitation may be used that can be installed for continuous operation.
Motor-actuated rotary valves 13 in lines 12 and 12 A are arranged to meter impure acid product from storage silo 10 into slurry holding tank 11 . Powder flow rate can be measured using a commercially available powder flow meter of the type which simultaneously measures density and velocity and then converts these measurements to mass flow rate. Slurry strength is then controllable by controlling the powder mass flow rate at a fixed ratio to the total solvent flow rate into slurry holding tank 11 . In the embodiment shown in FIG. 1 an alternative control scheme is illustrated using slurry density measurement. A feedback signal is generated from one or both of density measuring devices 15 which are located as shown downstream of slurry holding tank 11 . Slurry density is typically maintained at about 1085 kg/m 3 . The density measurement has a direct relationship to the slurry strength, i.e., density, and is used to adjust the crude acid flow rate into slurry holding tank 11 according to pre-selected set points. The density measurement is converted to a feedback signal which is transmitted via dotted line 16 to either one of motor control devices 17 , which, in turn, controls the rate at which the respective motor turns its corresponding rotary valve 13 . In practice, only one of line 12 or 12 A is used at a time in operating the process. Recycled water is introduced into slurry holding tank 11 via line 18 and control valve 19 , and fresh water can be added to slurry hold tank 11 via line 20 . In addition, solvent, typically cold demineralized water, can be introduced into slurry holding tank 11 via a flush water spray through the slurry holding tank vent line (not shown). The total flow of solvent into slurry holding tank 11 is controlled by a commercially available high- and low-level control means.
The purification stage is based on an overall process design whereby the aqueous slurry formed in slurry holding tank 11 is carefully controlled to maintain a solids strength in the range of 28% to 30% w/w based on a crude acid design flow rate of 55 tes/hr and a solvent design flow rate of 128.3 tes/hr. Slurry concentration can vary higher or lower, but usually such a variation will produce a corresponding economic penalty in overall process efficiency. The temperature in slurry holding tank 11 is maintained in the range of from 95° C. to 100° C., although this range is not critical, and the pressure is atmospheric.
To achieve the desired elevated level of temperature and pressure for hydrogenation, the aqueous slurry is pumped through a predetermined series of pre-heaters, i.e., heat exchangers. As shown greatly simplified in reference to FIG. 1, the slurry is pumped from slurry holding tank 11 via line 21 around a pressure control loop via a low pressure dissolver feed pump 22 . The low pressure dissolver feed pump is a horizontal centrifugal pump of suitable capacity and discharge pressure. Pressure in the control loop is typically maintained at about 10 bar (1000 kPa). Two process-operable filters 23 A & 23 B are positioned in parallel on the discharge side of low pressure dissolver feed pump 22 to remove any debris which may have found its way into the system. Only one of filters 23 A and 23 B is in use at any time. Slurry flows through a condensate injection heater (not shown) on its way to the suction side of high pressure dissolver feed pump 24 and then on to a first preheater 25 which raises the temperature of the slurry to an intermediate value in the range of 150° C. In operation, a series of high pressure dissolver feed pumps 24 boost the slurry pressure from about 10 bar (1000 kPa) to 110 bar (11,000 kPa) and deliver the slurry to the purification reaction stage through a train of preheaters. These additional preheaters, arranged in series (not shown), raise the temperature of the slurry to the required operating temperature for the purification reaction, which is in the range of 283° C. High pressure dissolver feed pumps are typically single-stage vertically mounted high-speed centrifugal pumps.
Slurry is withdrawn from slurry holding tank 11 through nozzle 26 located in the side wall of the holding tank. Nozzle 26 is sized to accommodate process design flow rates. With this configuration, undesirably large lumps of yet undissolved solid particles of crude acid are retained in the holding tank by perforated screen 27 positioned either internally as shown or externally over the opening for nozzle 26 whereby solid particles having an average particle size greater than 24 mm, i.e., too large to pass through the openings in the screen, are retained in slurry hold tank 11 and prevented from entering the downstream portion of the process until they have been sufficiently dissolved to pass through the screen openings. Although the description refers to “screen” 27 , any suitable retaining means, for example, expanded metal, drilled or punched metal sheet, for placement over the nozzle opening to temporarily retain undesirably large solid particles in the slurry holding tank can be used in practicing the invention.
The slurry strength in the feed to the preheaters determines the terephthalic acid/isophthalic acid strength in the hydrogenation reactor. The solution strength, therefore, is critical to successful operation of the reactor, and control of feed slurry strength is very important.
As many widely different embodiments of this invention may be made without departing from the spirit and scope thereof, it is to be understood that this invention is not limited to the specific embodiments thereof except as defined in the appended clams, and all changes which come within the meaning and range of equivalents are intended to be embraced therein. | An improved process for producing highly pure aromatic carboxylic acid from an impure solid acid product whereby the solid acid product is efficiently dissolved in a suitable solvent at relatively low temperatures despite the presence of solid lumps. | 2 |
BACKGROUND OF THE INVENTION
This invention relates to the distribution of electrical power to various load devices. More particularly, the invention concerns the distribution of building power to power receptacles, lighting devices and to other electrical equipment and appliances. The invention is especially adapted for supplying the electrical needs of office work stations.
It has been recognized that portable office partitions could be made more functional if the electrical power distribution to power receptacles and to lighting devices could be built into the panels and readily interconnected between adjacent panels. Such an approach is provided in U.S. Pat. No. 4,203,639, issued to Harold VanderHoek et al for a PANEL WIRING SYSTEM. However, such power distribution system must be designed into the structure of the partitions and is not readily adaptable to existing non-electrified partitions.
Another desirable feature of a power distribution system is the ability to control the application of electrical power to the load. Traditional load switching techniques are not only cumbersome and inflexible but are not compatible with the multitude of sophisticated control devices presently available. While control schemes have been suggested to provide control of multiple loads within, for example, a common office suite, such schemes have significant drawbacks. One such scheme encodes control information onto the high voltage power supply circuit, including the address of the intended "smart receptacle." The information is decoded at the load control device by logic circuitry in order to energize or deenergize the load. Another scheme utilizes radio transmission signals to send control information, including device addresses, to load control devices located throughout an office suite. Such schemes are not only overly complex and expensive, they have proven to be susceptible to radio frequency interference from various sources and have a limited number of addresses available. Furthermore, while it may be intended to limit the scope of control to a particular office or suite, there is no known practical approach to precluding interference with adjacent office suites and even adjacent buildings.
SUMMARY OF THE INVENTION
The present invention provides a power distribution system that is suitable for supplying switched power to an individual work station or to an entire office. The present invention additionally accommodates a multiplicity of different input control devices and is adaptable to the control of various types of loads. The invention further provides exceptional resistance to interference from external sources and provides secure control within a defined area.
The invention is embodied in a power distribution system having an electrical outlet strip including a case having a top wall for receipt of a plurality of power receptacles and side, bottom and end walls to enclose a space. A plurality of receptacles are provided on the case top and a power cable extends from the case for connection with a source of high voltage power. A low voltage input is provided and a circuit in the space defined by the case includes a switch electrically connected with the receptacles, the power cable and the low voltage input. The switch is responsive to a low voltage command signal applied to the input to electrically interconnect the receptacles and the power cable in order to apply high voltage power to the receptacles. The power distribution system additionally includes a user command input device for supplying a low voltage command signal to the low voltage input of the outlet strip.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a power distribution system embodying the present invention;
FIG. 2A-C illustrate several configurations of an embodiment of the invention;
FIG. 3 is a schematic diagram illustrating the interconnection of multiple high voltage connection devices with an input device;
FIG. 4 is a schematic diagram illustrating the circuit for a high voltage connection device;
FIG. 5 is a perspective view of an office work station showing a power distribution system being assembled thereto;
FIG. 6 is the same view as FIG. 5 with a fully assembled embodiment of a power distribution system;
FIG. 7a and 7b are a schematic diagram of a circuit for a touch responsive user input device for use with the circuit in FIG. 4;
FIG. 8 illustrates a touch switch panel for use with the circuit in FIG. 7a and 7b are; and
FIG. 9 illustrates another embodiment of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now specifically to the drawings, and the illustrative embodiments depicted therein, a power distribution system 10 includes one or more connection devices 12 and an input device 14 for supplying command signals to the connection device 12 that is connected thereto (FIG. 1). Each connection device 12 includes a connection 16 with a source of supply voltage 15. In the illustrated embodiment, the supply voltage is 120 volt, 60 Hz high voltage building power, although other sources of supply voltage may be used. For example, supply voltage 15 could be low voltage AC or direct current voltage. Each connection device 12 additionally includes a connection 18 for supplying high voltage power to a load 20. In the illustrated embodiment, load 20 is a power receptacle for receipt of the power cord from various user appliances, such as computers, small electrical appliances, lighting devices, or the like. However, the invention is not limited to the use with such power receptacles. For example, load 20 could be a lighting device with connection 18 being a hard-wired power cable to the lighting device.
Each connection device 12 includes a low voltage input connection 22 for receipt of a low voltage command signal. The first connection device 12 receives a low voltage command signal at input 22 from a line 28 extending from input device 14. Input device 14 produces a low voltage command signal on line 28 in order to cause the first high voltage device 12 connected to line 28 to connect its load 20 with its power connection 16. Each connection device 12 includes a low voltage output 30 which applies a low voltage command signal on a line 32 extending to the low voltage input 22 of another connection device 12. While line 32 is a hard-wire connection in the illustrated embodiment, an RF or infrared signal could be utilized Each connection device 12 provides a low voltage command signal at its low voltage output 30 in response to a low voltage command signal being received at its input 22. In this manner, a low voltage command signal produced by input device 14 causes all connection devices 12, connected in this manner, to connect their respective load 20 with its supply voltage 15 connected with connection 16. It may thus be seen that power distribution system 10 may be enlarged by connecting additional connection devices 12 in such ganged fashion as illustrated in FIGS. 1-3. High voltage connection device 12 provides a continuous low voltage power source on a line 24 connected with input device 14 in order to supply power to input device 14.
In FIGS. 2A-2C, input device 14 is illustrated as embodied in a touch control module 34 having a user-contact responsive touch panel 36 and a touch-responsive circuit 38 (FIGS. 7a and b and 8). Low voltage lines 24 and 28 are combined in a unitary low voltage cable 40 extending from touch control module 34 to the first connection device 12. In the embodiment illustrated in FIGS. 2A-3, the high voltage connection device is a power strip 42. The connection 16 for power strip 42 is in the form of a conventional power cable 44 for supplying high voltage electrical power from a building power grid, or from a built-in receptacle in an office partition. Power strip 42 includes a case, or housing, 46 having a top surface 48 as well as bottom and side surfaces. A plurality of power receptacles 50 are mounted to top surface 48 to provide switchable high voltage power to various electrical loads, which may be controlled from touch control module 34.
Power strip 42 defines a temporary power tap which may be readily installed by a user without the use of tools, while complying with presently applicable electrical codes. Another low voltage cable 52 is illustrated extending from the power strip 42 that is connected directly with touch control module 34, to another power strip 42 (FIG. 2B) and from the second power strip 42 to another power strip 42 (FIG. 2C). This ganged interconnection may be continued in order to connect additional power strips 42 into a power distribution system that is switchable "on" and "off" (energized and deenergized) by a single touch control module 34. As will be set forth in more detail below, features of the disclosed embodiment facilitate the use of a theoretically unlimited number of power strips 42 in a power distribution system 10 controlled by a single touch control module 34. Power cable 44 for each power strip 42 is individually connected with the building's power grid. Accordingly, power cables 44 may be interconnected with the same or different circuits in the power grid in order to avoid the overloading of any one particular circuit as a result of an excessive number of appliances being powered from power strips 42.
In the illustrated embodiment, low voltage input includes a conventional telephone line jack 53 and low voltage output 30 includes a conventional telephone hand-set jack 54 (FIG. 3). Accordingly, cable 40 includes a conventional telephone line plug 58 at its terminal end. Low voltage cable 52 includes a telephone hand-set plug 56 at one end and a line plug 58 at its opposite end. Because line plug 58 is not compatible with hand-set jack 54 and hand-set plug 56 is not compatible with line jack 53, this configuration reduces the risk that a user will misconnect power distribution system 10. Furthermore, low voltage cables 40 and 52 may be supplied from readily available components which are manufactured by numerous companies. In the illustrated embodiment, line jack 53 is marketed by the Amp Company under Part No. 520242-2, hand-set jack 54 under Part No. 520241-2, hand-set plug 56 under Part No. 5-641335 and line plug 58 under Part No. 5-641334.
Each high voltage connection device, such as power strip 42, includes a switching circuit 60 (FIG. 4). Switching circuit 60 includes a relay CR1 having a low voltage coil 62 and a set of high voltage contacts 64. One contact 64 is connected by line 66a, through a circuit breaker 68 and a line 66b, to power cable 44. The other contact 64 is connected through a line 70 to the "hot" terminal of power receptacles 50. Line 66a additionally extends to the primary winding 72 of a transformer 74. Primary winding 72 is additionally connected by a line 76 to the neutral wire of power cable 44 and to the neutral contacts of power receptacles 50. A low voltage winding 78 of transformer 74 is connected with a full wave rectifier U1 to provide an unregulated low voltage power supply 77. Low voltage power supply 77 provides a full wave rectified signal on lines 80 and 81 that is filtered by a filter capacitor C1 across lines 80 and 81. However, in the preferred embodiment, no additional voltage regulation is provided for power supply 77. Voltage regulation not only adds expense but creates thermal management problems.
Line 80 is connected through a Darlington transistor portion of an optical coupler U2 to a line 82 that is connected to low voltage coil 62 of relay CR1. The opposite terminal of coil 62 is connected to line 81. Input diode 84 of optical coupler U2 is connected through a line 86 and a line 88, having a series resistor 89 therein, to low voltage input 22. Unregulated low voltage power supply lines 80 and 81 are additionally supplied to low voltage input connection 22. Lines 82 and 81 extend to low voltage output connection 30.
With power cable 44 connected to a source of high voltage electrical power, relay CR1 is energized to interconnect appliances plugged into power receptacles 50 whenever a DC voltage is supplied across lines 86 and 88 sufficient to cause diode 84 to switch transistor pair 79 into conduction. When transistor pair 79 conducts, a path is established from line 80 through transistor 79 and line 82 to coil 62 in order to apply a positive low voltage signal across coil 62. Simultaneously, a positive DC voltage is applied across lines 82 and 81 that are supplied to output connection 30. In this manner, a low voltage signal applied to input connection 82 causes relay CR1 to interconnect power receptacles 50 with the source of high voltage power connected with power cable 44 and causes a low voltage command signal to be produced at low voltage output connector 30. Thus, another power strip 42, whose low voltage input 22 is connected with low voltage output 30 of the particular power strip, will have its power receptacles 50 energized in a similar fashion. The low voltage command signal supplied to low voltage output connection 30 is derived from low voltage power supply 77, which is powered from the high voltage source 15 through cable 44 of the associated power strip 42. Thus, the load placed on the source of the low voltage command signal presented to input connection 22 is the same whether an additional power strip 42 is connected with output connector 30 or not. Therefore, additional power strips 42 may be combined in power distribution system 10 without providing additional load on the source of the low voltage input command signal. In this manner, a theoretically unlimited number of power strips 42 may be connected in power distribution system 10 without requiring a corresponding increase in the current supply capabilities from touch control module 34.
Optical coupler U2 provides isolation between low voltage input 22 and switching circuit 60. The connection of lines 80 and 81 to low voltage input 22 provides a source of supply voltage for touch control module 34. In this manner, touch control module 34 does not require a separate power supply, nor a separate cable to supply its power requirements. When a low voltage output connector 30 is used as the source of the command signal for low voltage input 22, no connection is made to the voltage supply lines 80 and 81 of the next power strip.
In the illustrated embodiment, the low voltage command signal provided to the low voltage input 22 of the first power strip 42 is produced by touch-responsive circuit 38 (FIGS. 7a and 7b. Touch control module 34, including touch panel 36 and touch-responsive circuit 38 are disclosed in detail in commonly-owned, copending application Ser. No. 535,111 filed concurrently herewith, for a TOUCH SENSITIVE CONTROL CIRCUIT by David Caldwell et. al., the disclosure of which is hereby incorporated herein by reference. The details of such touch control module will not be repeated herein. Suffice it to say that touch panel 36 includes a first conductive touch pad 90 mounted to a substrate, such as glass panel 92, for receiving a user "ON" selection to energize power receptacles 50. A second conductive touch pad 94 on substrate 92 receives a user "OFF" selection to deenergize receptacles 50. The capacity of a user contacting touch pad 90 or 94 is detected by conductive pads 95 through 98 mounted via a mylar carrier 99 to substrate 92 opposite touch pads 90 and 94. Pads 95 through 98 and a ground plane are connected by a connector 100 to a connector 102 of touch responsive circuit 38. Circuit 38 includes an output latch 104 whose output 106 is connected through a diode 107 to the base 108 of a transistor Q1. Base 108 is connected through a pull-up resistor 109 to the positive supply voltage rail 112. The emitter of transistor Q1 is grounded and its collector 110 is connected to line 88 (FIG. 4). Line 86 (FIG. 4) is connected through line 116 and resistor 114 to voltage rail 112. Circuit 38 further includes logic processing means, generally shown at 140, between connector 102 and output latch 104 for determining that a user has touched one of the touch pads 90, 94. Logic processing means 140 includes a plurality of low offset, temperature-compensated comparators 142a-142f. Comparators 142a-142f perform logic functions utilizing a "floating" reference which varies in proportion to the variation of the supply voltage on rail 112. Logic processing means 140 is additionally substantially insensitive to significant changes in its supply voltage because it incorporates time delays that are ratio metric and that they are established to maintain a relative timing sequence not withstanding a significant modification in their absolute values.
If the user contacts "OFF" touch pad 90, latch circuit 104 produces a steady low output 106, which clamps base 108 of transistor Q1 low and prevents Q1 from conducting. With Q1 nonconducting, no current is supplied to diode 84 of U1 (FIG. 4) and coil 62 of relay CR1 is deenergized. When the user contacts "ON" touch pad 94, latch 104 changes state and its output 106 has a positive voltage, which allows resistor 109 to provide a drive current to base 108 of transistor Q1. This drives Q1 into conducting, which provides a voltage across lines 86 and 88 to supply a current to diode 84.
In the illustrated embodiment, the voltage across lines 80 and 81 change from approximately 24 volts to 12 volts when relay CR1 becomes energized because power supply 77 is substantially unregulated. However, touch-responsive circuit 38 is ratiometric, in that it is capable of satisfactory performance notwithstanding the drastic swing in its supply voltage. This provides a significant cost savings to power distribution system 10 because it eliminates a voltage regulator from each power strip 42. Although the voltage across lines 80 and 81 change significantly, depending upon the state of relay CR1, a zener diode D1 across coil 62 prevents a momentary application of 24 volts across coil 62 during the interval between transistors 79 beginning to conduct and the voltage across lines 80 and 81 dropping as a result thereof. Diode D1 additionally provides reverse voltage spike protection to coil 62.
Because conventional telephone jacks are used for low voltage input and output connections 22 and 30, switching circuit 60 is configured to reduce the risk of damage to a telephone or telephone hand-set, or to circuit per se, if a user inadvertently connects a telephone hand-set to jack 54 or connects a telephone line to jack 53. If a telephone line is connected to jack 53, approximately 100 volts ringing signal could be applied across lines 86 and 88. Resistor 89, which in the illustrated embodiment, is 1.0K ohms, limits the current that is developed to avoid damage to network U2 under such circumstances. If a telephone hand-set is connected to jack 54, the low voltage output command signal on lines 81 and 82 would be applied to the speaker of the telephone hand-set. The impedance of the speaker would be sufficient to limit the resulting current to relatively harmless levels.
Installation of power system 10 in a work station is illustrated in FIGS. 5 and 6. As many power strips 42 as desired are assembled under a work surface 120 and touch control module 34 is positioned above work surface 120 in openings (not shown) provided for such mounting purpose. Low voltage cable 40 is extended from touch head 34 to the first power strip 42 and low voltage cable 52 is extended between power strips 42 in the manner previously set forth. Power cables 44 are plugged into continuously-powered receptacles 122 supplied from the building power grid. Power distribution system 10 is now fully set up and any appliances, such as computers, calculators, lights, or the like, plugged into receptacles 50 will be commonly energized and deenergized from touch control module 34.
Although a lighting unit 124 is shown in FIG. 6 as having a power cord 126 plugged into one receptacle 50 of power strip 42, an alternative configuration would be to provide switching circuit 60 internal to lighting device 124 and to directly control the application of high voltage electrical power to lighting device 124 by a low voltage cable 52 connected therewith. In such a configuration, power cord 126 of lighting device 124 would be plugged directly into continuously-powered receptacles 122. As a further alternative, rather than providing power strips 42 as externally mounted temporary power taps, a switching circuit 60 could be built into power raceway 128 such that receptacles 122 would be directly switchable from touch control module 34. Other variations would suggest themselves to those skilled in the art.
Although the invention is illustrated receiving a low voltage command signal from touch control module 34, other sources of the command signal are possible. In FIG. 9, a local area network, or LAN, 130 includes a plurality of computers 132 in a network configuration. Because the low voltage input 22 to high voltage connection device 12 is compatible with TTL logic, connection device 12 is capable of being energized and deenergized directly from outputs of one of the computers 132. This allows for the automatic power-up and power-down of various portions of an office in response to the programming of computer 132, as well as other variations that will be readily apparent. Other input devices 14 include motion detectors as well as infrared, ultraviolet and thermal-gradient detectors for use in building security. Electronic clock devices and common mechanical rocker switches are also suitable input devices. By utilizing a keypad and security software, actuation of load 20 could be limited to particular individuals possessing appropriate security codes. If a computer is the load 20, rather than an input device, a keypad would provide security capabilities to power distribution system 10 to limit access to the computer.
Because the power distribution system disclosed herein is operated with a switchable, constant DC voltage, it is extremely insensitive to electromagnetic interference. Because the system boundaries are established by hard-wire connection, there is virtually no risk of inadvertent interference from adjacent systems. Power distribution system 10 is relatively inexpensive and may be set up with minimal wiring interconnections. The power distribution system disclosed herein may be adapted to virtually any application in which it is desirable to control the energization and deenergization of a load.
Although switch circuit 60 is illustrated using an electromechanical relay, solid state devices may be used in certain applications. Additionally, it may be advantageous to use normally-closed rather than normally-open relay contacts to allow plug strip 42 to operate as a conventional plug strip by eliminating a connection with an input device. Other changes and modifications in the specifically described embodiments can be carried out without departing from the principles of the invention, which is intended to be limited only by the scope of the appended claims, as interpreted according to the principles of patent law including the doctrine of equivalents. | A user operable power distribution system that is suitable for supplying switched power to an individual workstation, or to an entire office, includes a user command module, such as a touch panel, for supplying low voltage command signals and a plug strip, which responds to the low voltage command signal to interconnect a load with a supply voltage, such as an AC power outlet. An unregulated power supply is provided in the plug strip and supplies the low voltage requirements for the switching circuit in the plug strip. In addition, the unregulated low voltage is supplied to the user command module to provide its low voltage power requirements. | 7 |
FIELD OF THE INVENTION
This invention relates to power supply apparatus for supplying electrical power to a number of remotely situated telecommunications devices, such as telephones, and to an assembly comprising such apparatus connected to a plurality of telephones.
BACKGROUND OF THE INVENTION
A conventional telephone exchange can serve a large number of telephones connected to the exchange along corresponding lines which are of differing lengths as a result of differences in the distances of the telephones from the exchange. As well as relaying telecommunications signals, the exchange also feeds to each line sufficient power to operate the telephones. That power can vary from one telephone to another in view of the differing lengths of the lines, which give rise to differences in the amount of resistive losses on the various lines.
The variation in power requirements is accommodated by means of a number of subscriber line interface circuits (SLICS), each of which relays through a respective line a sufficient amount of power to operate its respective telephone. If linear SLICs are used, excess power supplied to each circuit from the source is dissipated as heat. In this case, the voltage applied to each SLIC from the power source has to be sufficient to operate the telephone connected by the longest line. If a large number of other telephones are connected on much shorter lines, a relatively large amount of power has to be dissipated by the SLICs associated with the shorter lines, which can be uneconomical and leads to cooling problems in the exchange.
Some exchanges use SLICs which have individual internal switch mode power supply units which reduce the power dissipation. However, such SLICs are relatively expensive.
SUMMARY OF THE INVENTION
According to the first aspect of the invention, there is provided power supply apparatus for connection to a plurality of remotely situated telecommunications devices along corresponding lines, the apparatus comprising a plurality of interface circuits, each having an input for connection to a common power source and an output for connection to a respective line, each interface circuit, when active, feeding sufficient power, derived from the source, to the line to provide the required amount of power to operate the respective telecommunications device, dissipating any excess power supplied to the interface circuit from the source, wherein the apparatus includes common power regulation means for monitoring a characteristic of the amount of power being fed by each active interface circuit to its respective line and so controlling the power supplied to each active interface circuit that said supplied power is substantially equal to the largest of the amounts of power required by the active interface circuits.
Thus the power regulation means ensures that the power supplied to all the interface circuits is governed by the requirements of the active interface circuit which has to feed the most power to its respective line. The invention therefore helps to reduce the amount of power which needs to be dissipated by the active interface circuits, particularly when the interface circuits with the highest power requirements are not active, and thus enables the apparatus to use relatively cheap linear SLICs, whilst avoiding, or at least ameliorating problems arising from the power dissipation in the SLICs.
Conveniently, the characteristic monitored by the regulating means is the respective voltage applied by each active interface circuit to its respective line, and the regulating means controls the power supplied to the interface circuits by controlling the voltage applied to the inputs of the interface circuits.
Conveniently, the apparatus is adapted to be connected to a source of dc power, for example, a battery.
The power regulation means preferably includes a switch mode power supply unit operable to reduce the voltage supplied by the dc source to the interface circuits.
Preferably, the interface circuits are mounted on a single card for mounting in a rack.
Preferably, the apparatus has a plurality of such cards, and the regulating means is one of a plurality of such means each associated with a respective card.
The use of a plurality of cards and associated regulating means enables -he allocation of lines to interface circuits to be such that the interface circuits on each card are connected to a number of lines of similar lengths, thereby reducing the range of powers to be fed by the interface circuits in each respective card. That reduction in range enables the amount of power dissipated by the interface circuits to be further reduced.
According to the second aspect of the invention, there is provided a telephone exchange having power supply apparatus in accordance with the first aspect of the invention connected to a plurality of remotely situated telephones along corresponding lines which are not necessarily of the same resistance, and to a dc power source.
Preferably, the apparatus has a plurality of cards, each having a respective set of interface circuits and all the lines connected to the circuits on each cards are of lengths which lie in a respective one of a plurality of different ranges.
The invention also lies in power regulation means for use in apparatus in accordance with the first aspect of the invention, the power regulation means comprising a power input for connection to a battery, a plurality of further inputs, each for connection to the output of a respective interface circuit, monitoring means connected to said further inputs for monitoring the voltage, or current fed, by each active interface unit to a respective line connecting that interface unit with a respective telecommunications device, the monitoring means being operable to determine, at any one time, the maximum of said voltages or currents; and control means for applying to all said interface circuits an output voltage, derived from said battery voltage, substantially equal to the largest of the voltages required by an active interface circuit.
Preferably, the monitoring means is arranged to monitor the voltages applied by said active interface circuits and to determine the largest of said voltages.
BRIEF DESCRIPTION OF THE DRAWINGS
Power supply apparatus in accordance with the invention will now be described, by way of example, with reference to the accompanying drawings in which:
FIG. 1 is a schematic block diagram of the apparatus when connected to a number of telephones;
FIG. 2 is a block diagram of an interface circuit forming part of the apparatus shown in FIG. 1;
FIG. 3 is a block diagram of another part of the apparatus;
FIGS. 4 and 5 are diagrams illustrating the operation of the interface circuits;
FIG. 6 shows an alternative type of interface circuit for use in apparatus not in accordance with the invention; and
FIG. 7 shows an exchange having a subrack containing a plurality of power supply apparatuses in accordance with the invention.
DETAILED DESCRIPTION
The power supply apparatus shown in FIG. 1 forms part of a telephone exchange 2 which is connected to a number of telephones, 4 , 6 , 8 and 10 along corresponding lines 12 , 14 , 16 and 18 , each comprising a pair of conductors (A and B). For the sake of clarity, only 4 telephones are shown in the drawing, although typically the apparatus will serve between 6 and 15 telephones (or other telecommunications devices such as fax machines).
The apparatus in this example operates under a constant current protocol, which applies in the UK, by supplying a predetermined current to each telephone which is in use. However, apparatus in accordance with the invention can operate under different protocols, for example, the constant resistance requirements applicable in the USA.
The telephones are located at various different distances (in the range 0-5 km) from the exchange 2 , and as a result, the connecting lines are not all of the same length. However, the lines have the same resistivity, and therefore do not house the same resistance.
Each of the lines 12 , 14 , 16 and 18 is connected to a respective one of four identical linear subscriber line interface circuits (SLICs) referenced 20 , 22 , 24 and 26 . The subscriber line interface circuits all have inputs for the electrical power needed to operate the telephones 4 , 6 , 8 and 10 , and those inputs are connected in parallel, as indicated by line 28 to regulating means 30 in the form of a compensating power supply.
The single line interface circuit 20 is shown in greater detail in FIG. 2, in which the resistor Rloop represents the resistance of the line 12 and telephone 4 . The circuit 20 comprises an amplifier 50 controlled by a feedback loop which includes an anti-saturation circuit 52 and an external programming resistor Rdc. The amplifier 50 applies a voltage, Vab, to the line 12 causing a current to flow therealong.
In the case of a constant current system, the current supplied by the amplifier is fixed unless the anti-saturation circuit 52 is activated. In the case of a constant resistance system, the voltage at the output of the amplifier 50 is fed back, as indicated by the dotted line 54 , to simulate a constant resistance. Again, this may be modified by the anti-saturation circuit 52 (in the case of longer lines).
The anti-saturation circuit 52 provides a constant headroom voltage for the transmission of voice frequency (VF) signals, and will, if necessary, reduce the current (and hence Vab) to maintain voltage headroom for VF signals. The amplifier 50 is supplied with a voltage Vreg by the regulating means 30 , and the difference between Vreg and Vab is dissipated in the amplifier 50 .
With reference to FIG. 3, the compensating power supply 30 has an input 32 for connection to a battery (not shown) or other source of dc power, and four monitor inputs 56 , 58 , 60 and 62 , each of which is connected to the output of a respective one of the interface circuits 20 , 22 , 24 and 26 . Each of the monitor inputs is in turn, connected to monitor circuitry 64 which monitors the voltages, V(AB) 1 - 4 , being applied to each interface circuit to its respective line (when the telephone connected thereto is in use), determines the maximum of those voltages and feeds a signal representative of that maximum to a voltage control unit 66 . The unit 66 is in turn connected to a power supply switching regulator 68 which is also connected to the power supply input 32 , and to an output 70 (connected to the line 28 ). The regulator applies to the line 28 a voltage which is less than or equal to the battery voltage, and which is controlled by the unit 66 so as to be related to the maximum voltage in a way described below.
In this example, the constant current requirement is used to determine the voltage which has to be supplied by each SLIC to its respective line, when in use; the voltage applied has to be sufficient to produce 30 mA of current along the respective line. In view of the differences in resistances of the lines 12 , 14 , 16 and 18 , that voltage will vary from one SLIC to another. Since each SLIC is a linear device, any excess power (i.e. power which is not then transmitted along the respective one of the lines 12 , 14 , 16 and 18 ) is dissipated as heat.
In use, switching regulator 68 of the compensating power supply 30 controls the voltage applied to the line 28 so that it is equivalent to that maximum voltage plus a bias voltage needed in order for the SLIC to operate. As a result, the power dissipated by the active SLIC which is applying the largest voltage to its respective line is minimised, and the power dissipated in the other active SLICs is less than would be the case if the full battery voltage were applied to all the SLICs.
It will be appreciated that the voltage supplied along the line 28 can vary depending upon which of the SLICs is in use at any one time.
As shown in FIG. 7, the components of the power supply apparatus can be mounted on a single card 74 accommodated in a rack 76 of a plurality of such cards, 74 , 78 , 80 , each of which serves a respective set of telephones. The allocation of telephones to cards is such that the distance of each member in a set from the exchange lies in a respective range associated with that set, so that the range of different voltages which have to be applied by the SLICs on any one card can, as far as is practicable, be kept to a minimum. For example, all the telephones connected to the card 74 are situated more than 1 km from the rack 76 , the telephones connected to the card 78 are situated in the range 300 m to 1 km and the telephones connected to the card 80 in the range 0 to 300 m.
A number of examples of the operation of the power supply apparatus on any one card, and of the resultant savings in dissipated power, are discussed below.
As explained above, all of the monitor inputs V(AB) 1 - 4 are examined and the output of the supply 30 is then adjusted to supply the voltage which will maintain the required subscriber line conditions on the worst active line (i.e. the line with the highest resistance). Some example cases are given below in which the battery voltage is 48 volts, V(ab) is the voltage applied to the line 28 , (and is equal to the voltage detected at the respective one of the inputs 50 , 58 , 60 , 62 ) and which assume a requirement of 30 mA constant current, telephone resistance of 400 ohms, subscriber line resistance of 200 ohms/km, and 5V bias required for line drivers.
With reference to FIG. 4, Rloop is the sum of the resistances of the telephone and the line, Rline and Rphone. Vab is the voltage which the SLIC has to apply to its line and Vreg is the voltage supplied to the SLIC by the supply 30 .
Case (a)
All subscribers active on very short lines (negligible line resistance).
Vab (max)=0.03×Rloop=0.03×400=12V.
Vreg=(0.03×400)+5=17V.
In this case V(reg) will be set to 17V, and the dissipation in each SLIC will be 0.15W (total of 0.6W for all 4 channels)
Without compensating power supply, the power dissipated would be 0.03×(48−(0.03×400)=1.08W for each channel, would have to be dissipated
Power saving is equivalent to 0.93W per channel.
Case (b)
3 subscribers active on very short lines ( 12 , 14 , 16 -negligible line resistance), one subscriber active on 300M line ( 18 ).
V(ab){ 12 , 14 and 16 }=(0.03×400)=12V.
V(ab){ 18 }=(0.03×(400+(0.3×200))=13.8V.
Vreg=13.8+5=18.8V.
In this case v(reg) will be set to 18.8V, and the dissipation in SLICs 20 , 22 , 24 will be 0.204W and in SLIC 26 will be 0.15W (total of 0.762W for all 4 channels).
Without compensating power supply, the power dissipated would be 0.03×(48−(0.03×400))=1.08W for SLICS 20 , 22 and 24 and 0.03×(48−(0.03×(400+(0.3×200))))=1.026W for SLIC 26 .
Power saving is equivalent to 0.876W per channel.
Case (c)
3 subscribers active on very short lines ( 12 , 14 , 16 ) (negligible line resistance), one subscriber active on 3 km line, ( 18 )
V(ab){ 12 , 14 and 16 }=(0.03×400)=12V
V(ab){ 18 }=(0.03×(400+(0.3×200))=30V
V(reg)=30+5=35V.
In this case V(reg) will be set to 35V, and the dissipation in SLIC 20 , 22 and 24 will be 0.69W and in SLIC 26 0.15W (total of 2.22W for all 4 channels).
Without compensating power supply the power dissipated would be 0.03×(48−(0.03×400))=1.08W for SLICs 20 , 22 and 24 0.03×(48−(0.03×(400+(0.3×200))))=0.54W for SLIC 26 .
Power saving is equivalent to 0.39W per channel.
Case (d)
1 subscriber active on very short line 12 (negligible line resistance), three subscribers active on 3km lines ( 14 , 16 , 18 ).
V(ab){ 12 }=(0.03×400)=12V.
V(ab){ 14 , 16 , 18 }=(0.03×(400+(0.3×200))=30V
V(reg)=30+5=35V.
In this case V(reg) will be set to 35V, and the dissipation in SLIC 20 will be 0.69W and SLIC 22 , 24 , 26 is 0.15W (total of 1.14W for all 4 channels).
Without compensating power supply the power dissipated would be 0.03×(48−(0.03×400))=1.08W for SLIC 20 and 0.03×(48−(0.03×(400+(0.3×200))))=0.54W for SLICS { 22 , 24 , 26 }.
Power saving is equivalent to 0.39W per channel.
When the apparatus is used in a constant resistance system, the model illustrated in FIG. 5 applies. The following calculations assume a requirement of 2×200 ohm constant resistance feed (Rfeed) from 50V (Vfeed), a telephone resistance (Rphone) of 400 ohms, a line resistance (Rline) of 200 ohms/Km (multiplied by the line length), and a 5V bias requirement for the line drivers. Again, Vab is the voltage applied by a SLIC to its line and Vreg is the voltage applied to the SLICS by the supply 30 . lloop is the current flowing along the line.
Case (e)
All subscribers active on very short lines (negligible line resistance).
Vab=50×400/(400+400)=25V
lloop=Vab/Rloop=25/400=62.5mA
Vreg=25+5=30V
In this case Vreg will be set to 30V, and the dissipation in each SLIC will be 0.3125W (total of 1.25W for all 4 channels).
Without compensating power supply the power dissipated would be 0.0625×(48−25)=1.44W for each channel.
Power saving is equivalent to 1.125W per channel.
Case (f)
3 subscribers active on very short lines (negligible line resistance), one subscriber active on 3 km line.
Vab{ 1 }=50×(400+600)/(400+600+400)=35.7V
lloop=Vab/Rloop=35.7/(400+600)=35.7mA
Vab{ 2 , 3 , 4 }=50×400/(400+400)=25V
lloop=Vab/Rloop=25/400=62.5mA
Vreg=35.7+5=40.7V
In this case Vreg will be set to 40.7V, and the dissipation in each SLIC{ 1 } will be 0.179W and in SLICs { 2 , 3 , 4 } will be 0.981W per channel (total power=3.122W).
Without compensating power supply the power dissipated would be 0.0357×(48−35.7)=0.439W for channel 1 and channels 2 , 3 , 4 power=0.0625×(48−25)=1.44W per channel (total power=4.76W).
Power saving is equivalent to 0.41W per channel.
An alternative control loop method would employ the SLIC output signal (usually available on commercial components) which gives an indication of the loop current. In constant resistance feed applications the minimum loop current will directly show the longest line and hence highest Vab.
For constant current feed, where all lines are in the constant current region, the loop currents will be equal, in this case the control voltage would be reduced until one of the SLIC's anti-saturation circuits (the one with the longest line) began to reduce the loop current. Consequently the corresponding monitor input would begin to fall below the constant current value and at this point the regulated supply would maintain its voltage keeping the SLIC just on the edge of the constant current and anti-saturation regions of operation. The monitor block in this case outputs the minimum voltage (Vmin).
A control voltage (Vreg) is produced from the maximum/minimum loop monitor voltage to enable adjustment of the switching regulator to supply the voltage which will maintain the required subscriber line conditions on this worst case line. This block also ensures the regulated voltage is within SLIC battery input operating range.
The SLIC shown in FIG. 6 is of a type having its own built-in regulator which operates, in a similar fashion to regulator 68 , to reduce the voltage applied from a battery, without dissipating excess power. An exchange incorporating such SLICs, however, is relatively costly.
Although the invention has been described in relation to telephone exchanges, it can also be used in various types of primary multiplexing equipment, such as primary multiplexers supplying subscriber line access and situated remotely from the telephone exchange. | A power supply has a plurality of single line interface circuits ( 20, 22, 24 and 26 ) each connected by a respective line, to a respective telephone ( 4, 6, 8 and 10 ) or other telecommunications device. Each SLIC applies a sufficient voltage derived from a battery to the line to operate the respective telephone, and dissipate any excess power supplied by the battery. The apparatus includes common power regulation means ( 30 ), which incorporates a switch mode power supply unit ( 68 ), and which monitors the voltages being supplied by the SLICs at any one time and reduces the voltages applied to the SLICs to substantially the maximum voltage required by any one of the SLICs, thereby reducing the amount of power dissipated by the SLICs. | 7 |
This application is a continuation of Ser. No. 130,121, filed Dec. 8, 1987, now U.S. Pat. No. 4,866,171, printed with a grant date of Sept. 12, 1989.
INFORMATION DISCLOSURE STATEMENT
Prior art cited under 37 CFR §1.97:
__________________________________________________________________________U.S. Patent DocumentsAA 4,644,061 2-1987 KimForeign Patent DocumentsAB 168,707 1-1986 European Patent Application (I) (Merck)AC 170,073 2-1986 European Patent Application (II) (Merck)AD 165,384 12-1985 European Patent Application (III) SankyoAE 8,514 3-1980 European Patent Application (IV) Beecham__________________________________________________________________________
European Application (I) (AB) discloses a broad group of compounds, but never specifically any compound with a structure that is suggestive of the group 5H-pyrazolo[1,2-a]triazolinium-6-yl. Pyridinium compounds are a focal point of the exemplified disclosure, including (5S,6S)-2-[2-(2,3-cyclohexeno-1-pyridinium)ethylthio]-6-[(R)-1-hydroxyethyl]-1-methyl-carbapenem-3-carboxylate (page 63, lines 1-3). European Application (I) (AB) also includes a disclosure of a list of 97 ring groups at Example 35 (pages 139-145), which discloses 97 heterocyclic rings, including the ring forming the group (5H-pyrazolo[1,2-a]triazolinium-6-yl) (page 140, line 10, left hand entry); if that variable is plugged into the formula at page 139, line 10, this would create the (1R,5S,6S)-2-[(5H-pyrazolo[1,2-a]triazolinium-6-yl)]thio-6-[(R)-1-hydroxyethyl]-1-methyl-carbapenem-3-carboxylate. In order to make the compound most relevant to the instant invention according to the generic teaching of the published patent application, it would be necessary to use a starting material 6-mercapto-5H-pyrazolo[1,2-a]triazolinium halide. However, a method for making 6-mercapto-5H-pyrazolo[1,2-a]triazolinium halide is not described in that application, nor is a method for making it described in the literature. The 2-(2,3-cyclohexeno-1-pyridinium)ethylthio group which is remote, as it is based upon the pyridinium group which is not suggestive of the instant (5H-pyrazolo[1,2-a]triazolinium-6-yl) group.
Kim (AA) and European Application II (AC) are cumulative. European Patent Application Merck (II) ("AC"), European Patent Application (III) to Sankyo ("AD") and European Patent Application (IV) Beecham ("AE") are cited in the European Search Report for the counterpart European application; each is given the designation "technological background".
SUMMARY OF THE INVENTION
In accordance with a first aspect of the invention there is provided a method of treatment for controlling or preventing a bacterial infection in a subject which comprises administering to said subject an antibacterially effective amount of (1R,5S,6S)-2-[(6,7-dihydro-5H-pyrazolo[1,2-a][1,2,4]triazolium-6-yl)]thio-6-[R-1-hydroxyethyl]-1-methyl-carbapenem-3-carboxylate or a pharmaceutically acceptable salt thereof.
In accordance with a second aspect of the invention there is provided an antibacterial composition comprising an antibacterially effective amount of (1R,5S,6S)-2-[(6,7-dihydro-5H-pyrazolo[1,2-a][1,2,4]triazolium-6-yl)]thio-6-[R-1-hydroxyethyl]-1-methyl-carbapenem-3-carboxylate or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable carrier therefor a second aspect of the invention there is provided (1R,5S,6S)-2-[(6,7-dihydro-5H-pyrazolo[1,2-a][1,2,4]triazolium-6-yl)]thio-6-[R-1-hydroxyethyl]-1-methyl-carbapenem-3-carboxylate. This compound also may be in the form of the corresponding acid or pharmaceutically acceptable salt, in which case there is included an anionic group balancing the traizolinium positive charge. As such an anionic group may be mentioned, for example, the chloride, acatate or carbonate. As the salt may be mentioned the alkali metal salts, for example, sodium.
There is provided a method for the preparation of (1R,5S,6S)-2-[(6,7-dihydro-5H-pyrazolo[1,2-a][1,2,4]triazolium-6-yl)]thio-6-[R-1-hydroxyethyl]-1-methyl-carbapenem-3-carboxylate, which comprises contacting (1R,5S,6S)-2-[4-pyrazolidinyl]thio-6-[R-1-hydroxyethyl]-1-methyl-carbapenem-3-carboxylic acid with ethyl formimidate hydrohalide under conditions to introduce iminomethyl substitution at each of the free hydrogen positions of the nitrogen atoms of the pyrazolidinyl nucleus, which would be expected to yield the compound (1R,5S,6S)-6-[(R)-1-hydroxyethyl]-1-methyl-2-[(1,2-diiminomethyl)-4-pyrazolidinyl]-thio-carbapenem-3-carboxylic acid, and recovering the in situ formed (1R,5S,6S)-2-[(6,7-dihydro-5H-pyrazolo]1,2-a][1,2,4]triazolium-6-yl)]thio-6-[R-1-hydroxyethyl]-1-methyl-carbapenem-3-carboxylate. Surprisingly, the (1R,5S,6S)-6-[(R)-1-hydroxyethyl]-1-methyl-2-[(1,2-diiminomethyl)-4-pyrazolidinyl]-thio-carbapenem-3-carboxylic acid is not recovered. The compound is produced in a transitory state, and is converted in situ into the (1R,5S,6S)-2-[(6,7-dihydro-5H-pyrazolo[1,2-a][1,2,4]triazolium-6-yl)]thio-6 -[R-1-hydroxyethyl]-1-methyl-carbapenem-3-carboxylate. In a preferred embodiment of this aspect of the invention, the ethyl formimidate hydrohalide is the hydrochloride or hydrobromide, and still more preferably is the hydrochloride. Preferably, the reaction is conducted in the presence of a buffer, which in one embodiment is a phosphate. The pH is generally from about 5 to about 9, and more preferably 6 to about 7.5, and the temperature is generally from about -15° C. to about 30° C., and preferably from about -5° C. to about +10° C.
DETAILED DESCRIPTION
As used herein, and unless otherwise specified, the compound "I" refers to both the compound (1R,5S,6S)-2-[(6,7-dihydro-5H-pyrazolo[1,2-a][1,2,4]triazolium-6-yl)]thio-6-[R-1-hydroxyethyl]-1-methyl-carbapenem-3-carboxylate, as well as the acid or pharmaceutically acceptable salt of such compound which includes an anionic group balancing the traizolinium positive charge. The compound (I) manifest high antibacterial activity, a strong action of inhibiting β-lactamase as well as improved resistance to kidney dehydropeptidase. The carbapenem compound (I) may be prepared by reacting a compound identified as the compound (II): ##STR1## wherein R 3 is a carboxyl protecting group, and R a is an acyl group.
with a mercapto reagent represented by the formula (III): ##STR2## wherein R b is an amino protecting group. to give a compound represented by the formula (IV): ##STR3## wherein R 3 and R b have the same meanings as above. and subjecting the compound of the formula (IV) to removal of the protecting groups R 3 and R b to give the carbapenem compound of the formula (V). ##STR4## and then, reacting the resulting compound of the formula (V) with alkyl formimidate to give the carbapenem compound represented by the above formula (I).
Immediately after the reaction of the compound (V) with the alkyl formimidate, a compound (1R,5S,6S)-6-[(R)-1-hydroxyethyl]-1-methyl-2-[(1,2-diiminomethyl)-4-pyrazolidinyl]-thio-carbapenem-3-carboxylic acid is formed, which exists briefly before there is conversion to the final product (I). Under the conditions of the present synthesis, the intermediate compound (1R,5S,6S)-6-[(R)-1-hydroxyethyl]-1-methyl-2-[(1,2-diiminomethyl)-4-pyrazolidinyl]-thio-carbapenem-3-carboxylic acid is not recovered but exists only as a transitory intermediate.
The carbapenem compound represented by the formula (II) to be employed as a starting compound in the process described above is known per se and may be prepared in such a manner as disclosed, for example, in Japanese Patent Publication (Laid-Open) No. 123,985/1981 or, more preferably, in accordance with the spatially selective method as indicated in Reaction Scheme A below and proposed by the present inventors (as disclosed, for example, in Japanese Patent Application No. 315,444/1986). ##STR5## wherein R 4 is hydrogen atom or a lower alkyl group; Z is tertiary-butyldimethylsilyl group; and R 3 and R a have the same meanings as above.
In the specification of the present application, the term "lower" stands for a group or a compound affixed with this term as having the numer of carbon atoms ranging from 1 to 7, preferably from 1 to 4.
The term "lower alkyl" referred to herein stands for a straight-chained or branched-chain hydrocarbon group having preferably from 1 to 6 carbon atoms and may include, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert.-butyl, n-pentyl, isopentyl, n-hexyl, isohexyl or the like.
The term "carboxyl protecting group" referred to herein stands for any group capable of protecting the carboxyl group of the compound involved without adversely affecting any other substituents and the reactions that follow and may include, for example, an ester residue such as a lower alkyl ester residue including, for example, methyl ester, ethyl ester, n-propyl ester, isopropyl ester, n-, iso-, sec- or tert.-butyl ester, n-hexyl ester or the like; an aralkyl ester residue including, for example, benzyl ester, p-nitrobenzyl ester, o-nitrobenzyl ester, p-methoxybenzyl ester or the like; and a lower aliphatic acyloxymethyl ester residue including, for example, acetoxymethyl ester, propionyloxymethyl ester, n- or iso-butyryloxymethyl ester, pivaloyloxymethyl ester or the like.
The term "acyl group" referred to herein stands for, in a narrower sense, a moiety obtainable by removing the hydroxyl group from the carboxyl group of an organic carboxylic acid as well as, in a broader sense, any acyl group derived from an organic sulfonic acid or an organic phosphoric acid. Such an acyl group may include, for example, a lower alkanoyl group such as acetyl, propionyl, butyryl or the like; a (halo)lower alkyl sulfonyl group such as methanesulfonyl, trifluoromethanesulfonyl or the like; a substituted or unsubstituted arylsulfonyl group such as benzenesulfonyl, p-nitrobenzenesulfonyl, p-bromobenzenesulfonyl, toluenesulfonyl, 2,4,6-triisopropylbenzenesulfonyl or the like; and diphenylphosphoryl.
The term "amino protecting group" referred to herein stands for groups usually employed in peptide chemistry, for example, phthaloyl, benzyloxycarbonyl, tert-butoxycarbonyl, p-nitrobenzyloxycarbonyl or the like.
Each of the steps of the Reaction Scheme A above for preparing the compounds represented by the formula (II) in a highly spatial selectivity will be described below more in detail.
The step (a) involves the reaction of the N-propionyl-1,3-thiazoline-2-thione derivative of the formula (VII) with a tin(II)triflate in the presence of a base to give an enolate and then the reaction of the resulting enolate with the compound of the formula (VI) to give the azetidin-2-one derivative of the formula (VIII).
The enolization reaction of the N-propionyl-1,3-thiazoline-2-thione derivative of the formula (VII) with the tin(II)triflate may be carried out usually in a solvent inert in the reaction, such as an ether, i.e., diethyl ether, tetrahydrofuran or the like; a hydrocarbon, i.e., toluene, xylene, cyclohexane or the like; a halogenated hydrocarbon, i.e., dichloromethane, chloroform or the like. Preferably tetrahydrofuran can be used.
Reaction temperatures are not limited to a particular range of temperatures and may vary in a wide range with starting materials to be used or the like. Usually the reaction temperatures may be in a range of relatively low temperatures as low as from approximately -100° C. to about room temperature, preferably from approximately from -78° C. to approximately 0° C.
A quantity of the tin(II)triflate with respect to the compound of the formula (VII) is not critical and may range usually from approximately 1 mole to approximately 2 moles, preferably from 1 to 1.5 moles, of the tin(II)triflate per mole of the compound of the formula (VII).
The enolization reaction above is carried out usually in the presence of the base including, for example, a tertiary amine such as triethylamine, diisopropylethyl amine, 1,4-diazebicyclo-[2,2,2]octane, N-methylmorpholine, N-ethylpiperidine, pyridine or the like. N-Ethylpiperidine is employed advantageously. The base may be used at a rate ranging generally from approximately 1.0 to approximately 3 molar equivalents, preferably from 1.0 to 2 molar equivalents, per mole of the compound of the formula (VII).
The enolization reaction as described above may be completed generally in approximately 5 minutes to approximately 4 hours, thus leading to the formation of the enolate.
After completion of the enolization reaction, the resulting enolate may be used as it is for further reaction with the compound of the formula (VI).
The resulting enolate is then subjected to the alkylation reaction with the compound of the formula (VI). The alkylation reaction may be conducted at temperatures in the range generally from approximately -100° C. to about room temperature, preferably from approximately from -78° C. to approximately -10° C. A quantity of the compound of the formula (VI) is not critical and may vary conveniently in a range generally from approximately 0.5 mole to approximately 5 moles, preferably from 0.5 to 2 moles, per mole of the compound of the formula (VII) used for the enolization.
The alkylation reaction may be carried out under such conditions as have been described above generally for approximately 5 minutes to approximately 5 hours, preferably for 5 minutes to approximately 2 hours.
The enolization and alkylation reactions may be carried out preferably in an inert atmosphere such as in the atmosphere of nitrogen gas or argon gas.
The reaction product obtained by the above reaction is then treated with water. For instance, after completion of the reaction, a phosphate buffer with approximately pH 7 is added, and a mixture is then stirred to be followed by filtration of undissolved materials. After filtration, the compound of the formula (VIII) is separated and purified in conventional manner, such as by means of extraction, recrystallization, chromatography and so on.
The step (b) is a step by which the compound of the formula (IX) may be prepared by reacting the azetidin-2-one derivative of the formula (VIII) obtained by the step (a) above with a magnesium malonate represented by the general formula: (R 3 OOCCH 2 CO 2 ) 2 Mg in the presence of imidazole.
The reaction is carried out preferably in an inert organic solvent such as, for example, an ether solvent, i.e., ether, tetrahydrofuran, dioxane or the like; a hydrocarbon solvent, i.e., toluene, xylene, cyclohexane or the like; a halogenated hydrocarbon solvent, i.e., dichloromethane, chloroform or the like; acetonitrile and so on. Particularly acetonitrile may be employed conveniently.
Reaction temperatures are not limited strictly to a particular range and may vary in a wide range with starting materials to be used or the like. They may range generally from approximately 0° C. to approximately 100° C., preferably around room temperature.
A quantity of the magnesium malonate with respect to the compound of the formula (VIII) may be about an equimolar amount, and the reaction may be completed in approximately 50 hours, preferably in approximately 20 hours.
The magnesium malonate to be used may include, for example, p-nitrobenzylmagnesium malonate, benzylmagnesium malonate, methylmagnesium malonate and so on. Among them, p-nitrobenzylmagnesium malonate is preferably used.
The step (c) is a step to eliminate a hydroxyl protecting group Z from the compound of the formula (IX) obtained by the step (b) above. The tertiary-butyldimethylsilyl group as the hydroxyl protecting group Z may be eliminated by subjecting the compound of the formula (IX) to acidic hydrolysis in a solvent such as methanol, ethanol, tetrahydrofuran, dioxane or the like in the presence of an acid such as a mineral acid, i.e., hydrochloric acid, sulfuric acid or an organic acid, i.e., acetic acid at temperatures ranging from 0° C. to 100° C. for reaction periods ranging from 0.5 to 18 hours.
The above step may yield the compound represented by the formula (X) in a quantitative amount.
The step (d) is a step by which the diazo compound of the formula (XI) may be prepared by treating the compound of the formula (X) obtainable by the above step (c) with an azide compound in the presence of a base in such an inert organic sovent as have been enumerated for the step (b) above.
The azide compound to be used in the step (d) may include, for example, p-carboxylbenzenesulfonyl azide, toluenesulfonyl azide, methanesulfonyl azide, dodecylbenzenesulfonyl azide or the like. The base to be used therein may include, for example, triethylamine, pyridine, diethylamine or the like.
The reaction may be carried out, for instance, by adding p-toluenesulfonyl azide in acetonitrile preferably in the presence of triethylamine at 0° C. to 100° C., preferably at room temperature for 1 to 50 hours. This reaction produces the diazo compound represented by the formula (XI) with high yield.
The step (e) is a step by which the diazo compound of the formula (XI) obtained by the step (d) above may be cyclized to give the compound of the formula (XII). This step may be carried out preferably in an inert solvent such as benzene, toluene, tetrahydrofuran, cyclohexane, ethyl acetate, dichloromethane or the like, preferably in toluene, at temperatures ranging from 25° C. to 110° C. for 1 to 5 hours in the presence of a metal catalyst such as a metal carboxylate compound including, for example, bis(acetylacetonato)Cu(II), CuSO 4 , copper powder, Rh 2 (OCOCH 3 ) 4 , rhodium octanoate, Pb(OCOCH 3 ) 4 or the like. As an alternative procedure, the above cyclization step may be carried out by subjecting the compound of the formula (XI) to irradiation from a light source through a Pyrex filter (its wavelength being larger than 300 nm) in a solvent such as benzene, diethyl ether or the like at 0° C. to 250° C. for 0.5 to 2 hours.
The step (f) produces the compound of the formula (II) by reacting the compound of the formula (XII) obtainable by the step (e) with a reactive derivative of an acid represented by the formula: RaOH. The reactive acid derivative may include, for example, an acid anhydride such as acetic acid anhydride, methanesulfonic acid anhydride, p-toluenesulfonic acid anhydride, p-nitrobenzenesulfonic acid anhydride, 2,4,6-triisopropylbenzenesulfonic acid anhydride, trifluoromethanesulfonic acid anhydride or the like or an acid halide such as an acid chloride, i.e., acetyl chloride, propionyl chloride, diphenylphosphoric chloride, toluenesulfonyl chloride, p-bromobenzenesulfonyl chloride or the like. Diphenylphosphoric chloride (R a =diphenylphosphoryl group) is particularly preferred.
The reaction of the compound of the formula (XII) with the reactive acid derivative may be carried out, for example, in a manner similar to a conventional acylation reaction in an inert solvent such as methylene chloride, acetonitrile, dimethylformamide or the like, conveniently in the presence of a base such as diisopropylethyl amine, triethylamine, 4-dimethylaminopyridine or the like at temperatures ranging from -20° C. to 40° C. for approximately 30 minutes to approximately 4 hours.
The reaction consisting of a series of the steps as have been described above provides the compound represented by the formula (II) with a highly spatial selectivity and with such a spatial arrangement that the methyl group at the 1-position of the carbapenem skeleton is arranged in the R configuration, the sustituent at the 5-position thereof is in the R configuration, and the substituent and the hydroxymethyl group each at the 6-position thereof are in the S and R configurations, respectively.
The compound represented by the formula (II) is then reacted with a mercapto reagent represented by the formula (III) to give the compound represented by the formula (IV).
The reaction of the compound of the formula (II) with the mercapto reagent of the formula (III) may be carried out, for instance, by reacting the compound of the formula (II) with the mercapto reagent of the formula (III) in an excess amount ranging from about equimolar amount to approximately 1.5 molar amount in an appropriate solvent such as tetrahydrofuran, dichloromethane, dioxane, dimethylformamide, dimethylsulfoxide, acetonitrile, hexamethylene phosphoramide or the like, preferably in the presence of a base such as sodium hydrogen carbonate, potassium carbonate, triethylamine, diisopropylethyl amine or the like at a temperature range from approximately -40° C. to approximately 25° C. for approximately 30 minutes to approximately 24 hours.
The reaction described above provides the carbapenem compound represented by the formula (IV) in which the carboxyl group at the 3-position thereof is protected by the carboxyl protecting group R 3 and the substituent at 2-position thereof is protected by the amino protecting group R b . The removal of the protecting groups R 3 and R b may be made by a per se known reaction for removing a protective group, such as solvolysis or hydrogenolysis. In a typical reaction, the compound represented by the formula (IV) may be treated, for instance, in a mixture of solvents such as tetrahydrofuran-water, tetrahydrofuran-ethanol-water, dioxane-water, dioxane-ethanol-water, n-butanol-water or the like containing morpholino-propane sulfonic acid-sodium hydroxide buffer solution (pH 7), a phosphate buffer solution (pH 7), dipotassium phosphate, sodium bicarbonate or the like, using hydrogen under 1 to 4 atmospheric pressures, in the presence of a catalyst for hydrogenation such as platinum oxide, palladium-activated carbon or palladium hydroxide-activated carbon at temperatures ranging from approximately 0° C. to approximately 50° C. for approximately 0.25 to approximately 4 hours.
In accordance with the above steps, (1R,5S,6S)-2-[4-pyrazolidinyl]thio-6-[(R)-1-hydroxyethyl]-1-methyl-carbapenem-3-carboxylic acid represented by the formula (V) is produced. Then, this compound of the formula (V) is converted to the present carbapenem compound of the formula (I) by reacting with alkyl imidoformate. The reaction with the compound of the formula (V) with alkyl imidoforamte may be conducted by dissolving the compound of the formula (V) in a week basic medium, for instance, in the basic medium (pH 8.5) consisting of a phosphate buffer(pH 7.5) and 1N-sodium hydroxide solution and causind a ethyl formimidate on the resulting solution.
The mercapto reagent of the formula (III) to be employed in the process described above may be prepared in a manner as indicated in Reaction Scheme B blow. ##STR6## wherein R b has the same meaning as above; X 1 and X 2 are halogen atoms as chlorine atoms; Ms is methansulfonyl groups; and R c is a lower acyl group such as acetyl, propionyl, butyryl group.
4-Hydroxyprazoline of the formula (XIII) prepared by the reaction between hydrazine hydrate and epihalohydrin is treated with the acylation reagent of the formula R b X 2 to give the compound of the formula (XIV). Then, the resulting compound of the formula (XIV) is converted to the compound of the formula (XV) by methansulfonylation, and the compound of the formula (XV) is reacted with the compound of the formula R c SH such as thiolacetic acid to obtain the compound of the formula (XVI). Finally, the resulting compound of the formula (XVI) is converted to the objective mercapto reagent of the formula (III) by reacting with alkali metal alkoxide such as sodium methoxide, sodium ethoxide or the like.
The compound of the present invention respresented by the formula (I) may be converted to a pharmaceutically acceptable salt therof by usually manner. Such a salt may be, for example, an alkali metal salt such as sodium, potassium salt thereof; an amino acid salt such as arginine, ornithine, lysine salt thereof; and an ammonium salt such as diethanolammonium, triethanolammonium salt thereof, but the sodium or potassium salt thereof may be more preferable described above.
The objective compounds of the formula (I) in accordance with the present invention represented by (1R,5S,6S)-2-(5H-pyrazolo[1,2-a]triazolinium-6-yl)thio-6-[(R)-1-hydroxylethyl]-1-methyl-carbapenem-3-carboxylic acids are novel compounds that are not disclosed specifically in the above-mentioned publication and that are extremely stable against dehydropeptidase (DHP) known as a kidney enzyme and superior in antibacterial activities. The remarkably high antibacterial activities and stability against the kidney DHP of the compound of the formula (I) according to the present invention have been determined by biological tests as will be described below.
I: Antibacterial Tests
Test Procedures:
The antibacterial activities were tested by an agar plate dilution method in accordance with the standard method of the Japanese Chemotherapy Society (Chemotherapy, Vol. 29, 76-79 (1981)).
A Mueller-Hinton (MH) agar liquid medium of a test microorganism was cultured overnight at 37° C. and the resultant culture medium was diluted with a buffered saline gelatin (BSG) solution to contain approximately 10 8 cells of the test microorganims per milliliter, and then the diluted solution was inoculated with a microplanter at the rate of approximately 5 microliters on a MH agar medium containing a test compound. This medium was then incubated at 37° C. for 18 hours. The minimum inhibitory concentration (MIC) is determined as a minimum concentration in which no test microorganism could grow. It is noted here that the test organisms used were all standard strains.
Results:
Table 1 shows the test results. It is to be noted here that the test compound used therein was the compound (15) obtained in Example No. 6. As control compounds were used ones clinically employed widely, viz., cefazolin (CEZ) as a cephalosporin compound, and imipenem as a carbapenem compound.
TABLE 1______________________________________ MIC (μg/ml) Test Compounds Compd.Test Organisms CEZ Imipenem (15)______________________________________Staphylococcus aureus FDA 0.2 0.025 0.05209P JC-1Staphylococcus aureus Terajima 0.05 <0.006 0.025Staphylococcus aureus MS352 0.1 0.013 0.1Streptococcus pyogenes Cook 0.1 <0.006 0.025Micrococcus luteus ATCC9341 0.39 0.025 0.1Bacillus subtilis ATCC6633 0.1 0.025 0.1Escherichia coli NIHJ JC-2 0.78 0.1 0.05Escherichia coli K12 C600 0.78 3.13 0.2Enterbacter aerougenes >100 3.13 0.39ATCC13048Enterobacter cloacae 963 >100 0.2 0.1Klebsiella pneumoniae PCI-602 0.78 0.39 0.05Salmonella typhimurium IID971 0.78 0.39 0.1Salmonella typhi 901 0.78 0.1 0.025Salmonella paratyphi 1015 1.56 1.56 0.39Salmonella schottmuelleri 8006 0.78 0.78 0.2Salmonella enteritidis G14 0.78 0.78 0.2Serratia marcescens IAM1184 >100 0.39 0.2Morganella morganii IFO3848 25 0.39 0.1Proteus mirabilis IFO3849 6.25 6.25 0.39Proteus vulgaris OX-19 6.25 0.78 0.025Proteus vulgaris HX-19 8.25 0.78 0.1Providencia rettgeri IFO 3850 12.5 0.78 0.2Pseudomonas aeruginosa >100 0.78 0.78IFO 3445Pseudomonas aeruginosa >100 0.78 0.78NCTC 10490______________________________________
From the foregoing results, it is apparent that the carbapenem compound according to the present invention has superior antibacterial activities.
II: Antibacterial Activities against Clinically Isolated β-Lactamase (Cephalosporinase) Producing Strains
Test Procedures:
The antibacterial activities against clinically isolated β-lactamase producing strains have been tested by the agar plate dilution method in accordance with the standard method of the Japanese Chemotherapy Society (Chemotherapy, Vol. 29, 76-79 (1981)). A solution of a cephalosporinase producing strain stored by Episome Research Institute, which was prepared by incubating the strain in a sensitivity test broth (STB; product of Nissui K.K.) for 18 hours, was diluted with a fresh STB solution to contain 105 cells per milliliter and the diluted solution was then inoculated as spots with a microplanter on a sensitivity disk agar-N (SDA; product of Nissui K.K.) containing a test compound. The disk agar was then incubated for 18 to 20 hours. A minimum inhibitory concentration was determined as a minimum concentration in which the test microorganism had no longer grown after a 18 to 20 hour incubation.
Results:
Table 2 shows the test results. It is to be noted here that the test compound used therein was the compound (15) obtained in Example No. 6. As control compounds were used ceftazidime (CAZ) as a cephalosporin compound, and imipenem as a carbapenem compound, both being recognized as having remarkably high antibacterial activities against the test strains and being widely employed clinically.
TABLE 2______________________________________MINIMUM INHIBITORY CONCENTRATIONS (MIC) MIC (μg/ml) Test Compounds Compd.Test Organisms CDZ Imipenem (15)______________________________________Providencia rettgeri GN 5284 0.2 0.39 0.2Providencia rettgeri GN 4430 0.2 0.39 0.2Providencia rettgeri GN 4762 0.78 0.39 0.2Escherichia coli GN 5482 0.78 0.1 0.025Escherichia coli No. 1501 0.2 0.1 0.025Escherichia coli No. 96 0.78 0.1 0.025Enterobacter cloacae GN 7471 3.13 0.2 0.1Enterobacter cloacae GN 7467 3.13 0.78 1.56Enterobacter cloacae GN 5797 0.39 0.39 0.1Proteus morganii GN 5407 0.39 3.13 1.56Proteus morganii GN 5307 0.2 0.78 0.39Proteus morganii GN 5375 0.2 3.13 1.56Proteus vulgaris GN 76 0.1 3.13 1.56Proteus vulgaris GN 7919 3.13 0.39 1.56Proteus vulgaris GN 4413 0.2 6.25 1.56Pseudomonas aeruginosa 6.25 0.78 1.56GN 918Pseudomonas aeruginosa 3.13 0.78 1.56GN 10362Pseudomonas aeruginosa 3.13 1.56 1.56GN 10367Serratia marcescens GN 10857 0.78 3.13 1.56Serratia marcescens L-65 0.2 0.39 0.2Serratia marcescens L-82 0.39 0.2 0.1Citrobactor freundii GN 346 25 0.39 0.78Citrobactor freundii GN 7391 >100 0.78 0.78Pseudomonas cepacia GN 11164 0.78 3.13 0.39Klebsiella oxytoca GN 10650 0.2 0.2 0.1______________________________________
It has been found from the above results that the carbapenem compound according to the present invention had the antibacterial activities against P. aeruginosa and P. cepacia belonging to Pseudomonadaceae as high as imipenem and particularly higher than CAZ having anti-Pseudomonas activities.
It has been further found that the carbapenem compound according thereto had the activities against enteric bacteria excluding the genus Proteus as high as imipenem and superior to CAZ.
III. Sensitivity Tests against Clinical Isolates
1. P. aeruginosa resistant strains
(1) Strains of Test Organisms:
Fifty-four strains of P. aeruginosa demonstrating a resistance against the following agents in such concentrations as having been indicated between the following parentheses were employed for sensitivity tests against clinical isolates. It is noted here that the 54 strains have been chosen because there have been the strains in duplicate with the agents.
______________________________________Ceftazidime (CAZ) (25 to 100 μg/ml) 21 strainsCefsulodine (CFS) (25 to <100 μg/ml) 23 strainsPiperacilin (PIPC) (25 to <100 μg/ml) 15 strainsGentamycin (GM) (25 to <100 μg/ml) 21 strainsAmikacin (AMK) (25 to <100 μg/ml) 26 strainsOfloxacin (OFLX) (25 to <100 μg/ml) 4 strains______________________________________
(2) Test Procedures:
The test procedures were based on the agar plate dilution method in accordance with the standard method of the Japanese Chemotherapy Society. A minimum inhibitory concentration (MIC) was determined in substantially the same manner as the test procedures II above using the 54 strains of P. aeruginosa having an anti-Pseudomonas resistance.
(3) Results:
The compound (15) obtained in Example 6, on the one hand, was found to demonstrate the antibacterial activities to inhibit the growth of approximately 98% of the test microorganisms in a concentration of 6.25 μg/ml and all the test microorganisms in a concentration of 12.5 μg/ml.
The imipenem, on the other hand, was found to inhibit the growth of approximately 98% of the test microorganisms in a concentration of 6.25 μg/ml and all the test microorganism in a concentration of 12.5 μg/ml.
2. C. freundii resistant strains
(1) Strains of the Test Organisms:
Twenty-strsins of C. freundii demostraing a resistance again st the following agent as same manner descrived above Test 1.
Cefixime (CFIX) (50 to >100 μg/ml)
Cefotaxime (CTX) (50 to >100 μg/ml)
(2) Test Rrocedures:
The tests were carried out in the same manner as descrived above Test 1.
(3) Results:
The compound (15) obtained in Example 6 was found to demonstrate the antibacterial activities to inhibit the growth of approximately 98% of the test microorganisms in a concentration of 0.78 μg/ml and all the test microorganisms in a concentration of 1.56 μg/ml.
The imipenem, on the other hand, was found to inhibit the growth of approximately 90% of the test microorganisms in a concentration of 0.78 μg/ml and all the test microorganisms in a concentration of 1.56 μg/ml.
From the above results, it has been found apparent that the compound according to the present invention is superior in the antibacterial activities to imipenem.
IV. Stability Test against Kidney Dehydropeptidase:
1. Materials:
(1) Swine Kidney Dehydropeptidase-I (DHP-I):
The swine kidney (8 kg) was homogenized and an enzyme protein was allowed to precipitate. After a connective lipid was removed with acetone, the resultant material was made soluble by treatment with butanol and purified in the order by the ammonium sulfate fraction method, thereby producing DHP-I enzyme from a 75% ammonium sulfate fraction.
The DHP-I enzyme was then adjusted to give an enzyme concentration of 25 mg/10 ml (phosphate buffer, pH 7.1), and divided into 1 ml portions. The portions were frozen and stored at -40° C. or less until use.
(2) Test Compound:
As a test compound was used the compound (15) obtained in Example 6 that follows.
The test compound was adjusted in situ to give the concentration of 117 μM with a 50 mM sodium phosphate buffer solution (pH=7.1).
As control compounds were employed glycyl dehydrophenylalanine (Gl-dh-Ph) and imipenem, and they were adjusted in situ each to give the concentration of 117 μM with the same sodium phosphate buffer solution.
2. Method:
(1) Measurement for Hydrolysis Activity against DHP-I Enzyme Substrate by Late Assay:
To 1.2 ml of a 50 mM sodium phosphate buffer solution (substrate) containing 117 μM of each of Gh-dh-Ph and imipenem as the control compounds was added 0.2 ml of the DHP-I enzyme solution (25 mg/10 ml) prepared above in the final substrate concentration of 100 μM. The solution was then incubated at 37° C. for 10 minutes. An initial velocity of hydrolysis of the substrate was measured from a decrease in absorbency at a particular λmax of each of the substrates.
A blank test was conducted in substantially the same manner as above by adding 0.2 ml of the sodium phosphate buffer solution (pH 7.1) to 1.2 ml of the above substrate.
(2) Measurement for Stability of Test Compounds against DHP-I by High Performance Liquid Chromatography Method (HPLC):
The test compound according to the present invention and the control compounds have been treated in substantially the same manner as (1) above. The incubation, however, was conducted at 37° C. for 4.5 hours or for 24 hours. A degree of the hydrolysis of the compounds each after the test periods of time was measured by the HPLC method.
3. Results:
The initial velocity of hydrolysis of each of the substrates against DHP-I by the late assay was found as follows:
Gl-dh-Ph: 17.4 μM/minute
Imipenem: 0.56 μM/minute
Table 3 below shows measurement results on stability of the compound according to the present invention and imipenem against DHP-I.
TABLE 3______________________________________DEGREES OF HYDROLYSIS BY DHP-I(Method: HPLC; Substrate Concentration: 100 μM; Unit: μM) Test CompoundsIncubation Conditions Imipenem Compound (15)______________________________________37° C., 4.5 hours 77.6 2.837° C., 24 hours * 2.9______________________________________ *After 24 hours at 37° C., it has been found that most or all imipenem has been decomposed and nothing remained was detected.
From the stability test results against DHP-I, it is found apparent that the carbapenem compound according to the present invention was stabler by approximately twenty-eight times than that of imipenem.
V. Toxicity:
Toxicological studies have been carried out using a group of 10 male mice of CrjCD(SD) type weighing from 20 to 23 grams. A solution containing the carbapenem compound (15) of the present invention obtained by Example 6 was administered subcutaneously to the mice and subjected to observations for one week.
The results have revealed that a group of the mice to which the carbapenem compound (15) of the present invention had been administered in the amount of 500 mg/kg were alive without any abnormal observations.
As have been described above, the carbapenem compounds according to the present invention demonstrate a wider scope of antibacterial spectra compared to conventional cephalosporin compounds and remarkable antibacterial activities comparative to imipenem as well as an overwhelmingly higher resistance against DHP compared to imipenem. The carbapenem compounds according to the present invention further possess superior antibacterial activities against clinically isolated strains and present favorable effects on infection preventive tests on mice against various organisms.
Therefore, the carbapenem compounds of the formula (I) according to the present invention permit a single administration without a combination with any other compounds and without a risk of any side effect that might be caused to arise in combination with a DHP inhibitor, unlike imipenem that was led for the first time to a practically useful antibacterial agent in combination with cilastatin acting as a DHP inhibitor. The carbapenem compounds are accordingly extremely useful as antibacterial agents for therapy and prevention of infectious diseases from various pathogenic organisms.
The carbapenem compound of the formula (I) according to the present invention may be administered as an antibacterial agent to the human being and other mammarian animals in the form of a pharmaceutically acceptable composition containing an antibacterially effective amount thereof. A quantity of administration may vary in a wide range with ages of patients, weights, patient conditions, forms or routes of administration, patient's diagnoses or the like and may be orally, parenterally or topically administered, usually, to adult patients once or in several installments per day in a standard daily dose range from approximately 200 to approximately 3,000 mg.
The pharmaceutically acceptable composition of the carbapenem compound of the formula (I) according to the present invention may cantain an inorganic or organic, solid or liquid carrier or diluent, which is conventionally used for preparations of medicines, particularly antibiotic preparations, such as an excipient, e.g., starch, lactose, white sugar, crystalline cellulose, calcium hydrogen phosphate or the like; a binder, e.g., acacia, hydroxypropyl cellulose, alginic acid, gelatin, polyvinyl pyrolidone or the like; a lubricant, e.g., stearic acid, magnesium stearate, calcium stearate, talc, hydrogenated plant oil or the like; a disintegrator, e.g., modified starch, calcium carboxylmethyl cellulose, low substituted hydroxypropyl cellulose or the like; or a dissolution aid, e.g., a non-ionic surface active agent, an anionic surface active agent or the like, and may be prepared into forms suitable for oral, parenteral or topical administration. The formulations for oral administration may include solid preparations such as tablets, coatings, capsules, troches, powders, fine powders, granules, dry syrups or the like or liquid preparations such as syrups or the like; the formulations for parenteral administration may include, for example, injectable solutions, drip-feed solutions, depositories or the like; and the formulations for topical administration may include, for example, ointments, tinctures, creams, gels or the like. These formulations may be formed by procedures known per se to those skilled in the art in the field of pharmaceutical formulations.
The carbapenem compounds of the formula (I) according to the present invention are suitably administered in the form of parenteral formulations, particularly in the form of injectable solutions.
The production of the carbapenem compounds of the formula (I) according to the present invention will be described more in detail by way of working examples.
In the following description, the following symbols are used to have the particular meanings:
ph: phenyl group
PNB: p-nitrobenzyl group
PNZ: p-nitrobenzyloxycarbonyl group ##STR7## tertiary-butyldimethylsilyl group Ac: acetyl group
Et: ethyl group
EXAMPLE 1 ##STR8##
To 15 g of hydrazine monohydratre in 50 ml flask was added dropwise, 9.3 g of epichlorohydrine at 0° C. for 1 hour and after dropwise, the reactione mixture was stirred for 2 hours at same temperature. After removal of the exess hydrazin under reduced pressure, 300 ml of a saturated sodium bicarbonate solution and 200 ml of tetrahydrofuran were added to the residue. To this solution was added dropwise a solution of 43 g of p-nitrobenzyloxycarbonyl chloride in 150 ml of tetrahydrofuran, hten the reaction mixture was stirred for 2 hours. After reaction, 200 ml of ethyl acetate was added to the reaction mixture, the organic layer was seoarated and water layer was extracted with 100 ml of ethyl acetate. The combined organic layer was washed with a saturated sodium chloride aqueous solution and dried over sodium sulfate. The soluvent was removed and 500 ml of chloroform was added to the residue then the resulting solution was stored in the refrigerater to give a precipitate. After removal of the precipitate, the soluvent was removed and the residue was purified using silica gel colum chromatography (dichloromethane) to give 16.7 g of the Compound 1.
NMR (CDCl 3 ) δ: 8.15 (4H, d), 7.48 (4H, d), 5.4-5.0 (1H, m), 5.37 (4H, s), 4.4-3.2 (4H, m).
EXAMPLE 2 ##STR9##
(a) To a solution fo 16.6 g of the Compound (1) obtained by Example 1 and 5.6 g of triethylamine in 200 ml of dichloromethane was added dropwise a solution of 6.42 g of methansulufonyl chloride in 20 ml of dichloromethane at 0° C. and the reaction mixture was stirred for 15 minutes at room temperature. After reaction, the organic layer was washed with 200 ml of water, 200 ml of a satulated sodium bicarbonate solution and 200 ml of a saturated sodium chloride solution and then dried over sodium sulfate. The solvent was removed to give 16.6 g of pale yallowish powder.
(b) A solution of 9.6 g of the above powder, 3.13 g of potassium acetate and 250 ml of acetone was refluxed for 2 hours. After addition of 50 ml of water, the reaction solvent was removed and the resulting residue was extracted with ethyl acetate. The organic layer was washed with water, dried over and removed. The resulting residue was purified using silica gel colum chromatography by chloroform as an eluent to give 5.9 g of pwder.
(c) To a solution of 13.6 g of the above powder, 145 g of tetrahydrofuran and 145 ml of methanol was added 12.3 ml of 4% sodium methoxide-methanol solution at 0° C. and the reaction mixture was stirred for 5 minutes. After reaction, 1N-hydrogen chloride solution was added to the reaction mixture and the resulting acidic solution was extracted with ethyl acetate. After washing and drying, the solvent was removed to give 11.9 g (63%) of the Compound (2) as pale brownish powder.
NMR (CDCl 3 ) δ: 8.17 (4H, d), 7.48 (4H, d), 5.28 (4H, g), 4.5-3.2 (4H, m).
EXAMPLE 3 ##STR10##
Tin triflate (3.712 g) was dissolved in 10 ml of anhydrous tetrahydrofuran under nitrogen gas streams, and the resulting solution was cooled to 0° C. To this solution was added 1.3 ml of N-ethylpiperidine and a solution of 1.2 g of the Compound (4) above in 7 ml of anhydrous tetrahydrofuran, and the mixture was stirred for 2 hours at the same temperature. To this was added a solution of 1.42 g of the Compound (3) in 2 ml of anhydrous tetrahydrofuran, and the resultant mixture was stirred for 1 hour. After the completion of the reaction, 100 ml of chloroform was added and the mixture was washed with a 10% citric acid aqueous solution. The organic layer separated was then dried over MgSO 4 and the solvent was removed leaving the residue that was in turn purified by a silica gel column chromatography with a n-hexane:ethyl acetate (2 - 1:1) mixture to give 1.93 g (97%) of the Compound (5) as a yellow solid material.
NMR (CDCl 3 ) δ: 0.07 (6H, s), 0.88 (9H, s), 1.21 (3H, d), 1.26 (3H, d), 3.30 (1H, dd), 3.28 (2H, t), 3.94 (1H, dd), 4.55 (2H, t), 6.24 (1H, bs). ##STR11##
Tin triflate (57.0 g) was dissolved in 164 ml of anhydrous tetrahydrofuran under nitrogen gas streams, and the resulting solution was cooled to 0° C. To this solution was added 19.9 ml of N-ethylpiperidine and a solution of 21.71 g of the Compound (6) above in 123 ml of anhydrous tetrahydrofuran and the mixture was stirred for 1.5 hours at the same temperature. To this was added a solution of 1.42 g of the Compound (3) in 123 ml of anhydrous tetrahydrofuran, and the resultant mixture was stirred for 1 hour. After the completion of the reaction, chloroform was added and the mixture was washed with a 10% citric acid aqueous solution and a sodium chloride aqueous solution. The organic solution separated was then dried over MgSO 4 and the solvent was removed leaving the residue that was in turn purified by a silica gel column chromatography with n-hexane:ethyl acetate (2:1) to give 33.57 g (98%) of the Compound (7) as a yellow solid material, m.p. 85.5°-86.5° C.
NMR (CDCl 3 ) δ: 0.07 (6H, s), 0.90 (9H, s), 1.00 (3H, t), 1.23 (3H, d), 1.26 (3H, d), 2.90 (1H, dd), 6.10 (1H, bs).
[α] D25 =+233.9° C. (C=0.77, CHCl 3 ). ##STR12##
To a solution of 30.66 g of the Compound (7) obtained in the step (B) above in 740 ml of anhydrous acetonitrile was added 12.13 g of imidazole, and the mixture was stirred under nitrogen gas streams at room temperature for 5.5 hours. To this was added 53.39 g of Mg(O 2 CCH 2 CO 2 PNB) 2 , and the mixture was stirred overnight at 60° C. The resultant reaction mixture was condensed under reduced pressures to 200 ml and 1 liter of ethyl acetate was added thereto. The organic layer separated was washed with a 1N-HCl aqueous solution, a 5% NaHCO 3 aqueous solution and a sodium chloride aqueous solution in this order. After dried over MgSO 4 , the solvent was removed and the residue was purified using a column chromatography with 800 g of silica gel, yielding 37.47 g of the Compound (8) as a colorless oily material.
NMR (CDCl 3 ) δ: 0.06 (6H, s), 0.87 (9H, s), 1.16 (3H, d), 1.20 (3H, d), 3.63 (2H, s), 5.27 (2H, s), 5.92 (1H, bs), 7.56, 8.24 (4H aromatic ring proton).
The Compound (8) obtained above was continued to be used in the following step (D) without further purification. ##STR13##
To 37.47 g of the Compound (8) obtained in the step (C) above in 392 ml of methanol solution was added 19.6 ml of concentrated HCl, and the mixture was stirred at room temperature for 1.5 hours. The reaction mixture was condensed to approximately 100 ml, and 800 ml of ethyl acetate was added. After the mixture was washed with water and then with a sodium chloride aqueous solution, it was then dried over MgSO 4 and the solvent was removed under reduced pressures, yielding the Compound (9) as a colorless oily material.
NMR (CDCl 3 ) δ: 1.25 (3H, d), 1.30 (3H, d), 2.90 (2H, m), 3.65 (2H, s), 3.83 (1H, m), 4.15 (1H, m), 5.27 (2H, s), 6.03 (1H, bs), 7.55, 8.27 (4H, aromatic ring proton).
The Compound (9) was then dissolved in 408 ml of anhydrous acetonitrile, and 36.31 g of dodecylbenzylsulfonyl azide and 13.8 ml of triethylamine were added. After the mixture was stirred at room temperature for 20 minutes, the solvent was removed leaving the residue that was in turn purified by means of column chromatography with 800 g of silica gel using chloroform:acetone (2:1) to give 21.57 g (as total yields of the Compounds (B), (C) and (D)) of the Compound (10) as a colorless oily material.
IR (CHCl 3 ) cm -1 : 2150, 1720, 1650.
NMR (CDCl 3 ) δ: 1.23 (3H, d), 1.30 (3H, d), 2.92 (1H, m), 3.50-4.30 (3H, m), 5.38 (2H, s), 6.40 (1H, bs), 7.57, 8.30 (4H, aromatic ring proton).
[α] D21 =-41.6° (C=3.1, CH 2 Cl 2 ). ##STR14##
In 134 ml of ethyl acetate was dissolved 21.57 g of the Compound (10) obtained in the step (D) above, and 0.065 g of rhodium octanoate was added. The solution was stirred at 80° C. for 0.5 hour and the solvent was removed, leaving the residue that was in turn dried to give the Compound (11) as a solid material.
IR (CHCl 3 ) cm -1 : 2950, 2925, 1860, 1830.
NMR (CDCl 3 ) δ: 1.22 (3H, d, J=8.0 Hz) 1.37 (3H, d, J=6.0 Hz) 2.40 (1H, bs) 2.83 (1H, q, J=8.0 Hz) 3.28 (1H, d, d) 4.00-4.50 (2H, m) 4.75 (1H, s) 5.28 and 5.39 (2H, ABq, J=12 Hz) 7.58, 8.24 (4H, aromatic ring proton). ##STR15##
To a solution of 186 mg of the Compound (11) obtained in the step (E) in 2 ml of anhydrous acetonitrile were added 0.11 ml of diphenylphosphoric chloride and 0.09 ml of diisopropylethyl amine under cooling with ice, and the mixture was stirred for 0.5 hour at the same temperature. After the reaction mixture was condensed, the residue was purified using a silica gel column, yielding 252 mg of the Compound (12) as a white solid material.
NMR (CDCl 3 ) δ: 1.24 (3H, d), 1.34 (3H, d), 3.30 (1H, q), 3.52 (1H, m), 4.10-4.40 (2H, m), 5.20 and 5.35 (2H, q), 7.29 (10H, m), 7.58 and 8.18 (4H, d).
EXAMPLE 4 ##STR16##
To a solution of 476 mg of the Compound (12) obtained in Example 3 in anhydrous acetonitrile was added a solution of 460 mg of the Compound (2) obtained in Example 2 and 0.17 ml of diisopropylethyl amine, and the mixture was stirred for 40 minutes under nitrogen atmosphere. Removal of the solvent left the reside that was in turn purified by means of silica gel column chromatography chloroform:acetone=3:1), yielding 667 mg (100%) of the Compound (13).
NMR (CDCl 3 ) δ: 1.24 (3H, d, J=6.0 Hz), 1.35 (3H, d, J=6.0 Hz), 3.2-4.4 (9H, m), 5.16 (1H, d, J=15.0 Hz), 5.26 (2H, s), 5.47 (1H, d, J=15.0 Hz), 7.3-7.7 (6H, m), 8.05-8.3 (6H, m).
EXAMPLE 5 ##STR17##
To a solution of 667 mg of the Compound (13) in 7 ml of tetrahydrofuran and 7 ml of water was added 120 mg of platium oxide, and the catalytic hydrogenation was carried out at room temperature for 1 hour under 3.0 atmospheric pressures. After removal of the catalyst, the solvent was removed to give 192 mg (74.0%) of the Compound (14) after lypophilization.
IR (KBr) cm -1 : 1750.
NMR (D 2 O--CD 3 OD) δ: 1.23 (3H, d, J=6.0 Hz), 1.40 (3H, d, J=7.0 Hz), 3.3-4.4 (9H, m).
EXAMPLE 6 ##STR18##
192 mg of the Compound (14) was dissolved in 15 ml of phosphate buffer solution (pH 7.0), and a pH of the solution was adjusted to 8.5 by 1N sodium hydroxide solution. To this solution was added 570 mg of ethyl formimidate hydrochloride, and the reaction mixture was stirred for 1 hour under ice-cooling. After the pH of the reactin mixture was adjusted to 7.0, the solvent was removed and the resulting residue was lyophilized. The resulting powder was purified using HP-40 column (water, 3% acetone-water) to give 76 mg (33.8%) of 6-[(R)-1-hydroxyethyl]-1-methyl-2-(5H-pyrazolo[1,2-a]triazolinium-6-yl)thio-cabapenem-3-carboxylic acid (Compound 15) after lyophilization.
NMR (D 2 O) δ: 1.32 (3H, d, J=6.0 Hz), 1.40 (3H, d, J=6.0 Hz), 3.3-4.4 (9H, m), 9.12 (2H, s).
The carbapenem compounds according to the present invention may be formulated in various preparation forms.
FORMULATION EXAMPLE 1 (INJECTION):
(1) Injectable suspension:
______________________________________Compound (15) 25.0 gMethyl cellulose 0.5 gPolyvinyl pyrolidone 0.05 gMethyl p-oxybenzoate 0.1 gPolysolvate 80 0.1 gLidocaine hydrochloride 0.5 gDistilled water to make 100 ml______________________________________
The above components were formulated to 100 ml of an injectable suspension.
(2) Lyophilization:
An appropriate amount of distilled water was added to 20 g of the sodium salt of the Compound (15) to make a total volume of 100 ml. The above solution (2.5 ml) was filled in vials so as for each vial to contain 500 mg of the sodium salt of Compound (15) and lyophilized. The lyophilized vial was mixed in situ with approximately 3-4 ml of distilled water to make an injectable solution.
(3) Powder:
The Compound (15) was filled in the amount of 250 mg in a vial and mixed in situ with about 3-4 ml of distilled water to make an injectable solution.
FORMULATION EXAMPLE 2
______________________________________Compound (15) 250 mgLactose 250 mgHydroxypropyl cellulose 1 mgMagnesium stearate 10 mg 511 mg/tablet______________________________________
The above components were mixed with each other and punched into tablets in conventional manner. Such tablets, as required, may be formulated into sugar coatings or film coatings in conventional manner.
FORMULATION EXAMPLE 3 (TROCHE)
______________________________________Compound (15) 200 mgSugar 770 mgHydroxypropyl cellulose 5 mgMagnesium stearate 20 mgFlavor 5 mg 1,000 mg/troche______________________________________
The component was mixed with each other and formulated into troches by punching in conventional manner.
FORMULATION EXAMPLE 4 (CAPSULES)
______________________________________Compound (15) 500 mgMagnesium stearate 10 mg 510 mg/capsule______________________________________
The component was mixed with each other and filled in conventional hard gellatin capsules.
FORMULATION EXAMPLE 5 (DRY SYRUP)
______________________________________Compound (15) 200 mgHydroxypropyl cellulose 2 mgSugar 793 mgFlavor 5 mg 1,000 mg______________________________________
The above components were mixed with each other and formulated into dry syrups in conventional manner.
FORMULATION EXAMPLE 6 (POWDERS)
______________________________________(1) Compound (15) 200 mg Lactose 800 mg 1,000 mg(2) Compound (15) 250 mg Lactose 750 mg 1,000 mg______________________________________
Each of the components was mixed with each other and formulated in powders in conventional manner.
PREPARATION EXAMPLE 7 (SUPOSITORY)
______________________________________Compound (15) 500 mgWitepsol H-12 700 mg(Product of Dynamite Noble) 1,200 mg______________________________________
The above components were mixed with each other and formulated into supositories in conventional manner.
The (1R,5S,6S)-2-[(6,7-dihydro-5H-pyrazolo[1,2-a][1,2,4]triazolium-6-yl)]thio-6-[R-1-hydroxyethyl]-1-methyl-carbapenem-3-carboxylate, including the various salt or charged acid forms, forms a crystalline structure in accordance with the following procedure. 45 mg (1R,5S,6S)-2-[(6,7-dihydro-5H-pyrazolo[1,2-a][1,2,4]triazolium-6-yl)]thio-6-[R-1-hydroxyethyl]-1-methyl-carbapenem-3-carboxylate was dissolved in 4 ml water. The resultant solution was filtered using Membran® filter (0.22 μm). The filtrate was lyophilized to give amorphous (1R,5S,6S)-2-[(6,7-dihydro-5H-pyrazolo[1,2-a][1,2,4]triazolium-6-yl)]thio-6-[R-1-hydroxyethyl]-1-methyl-carbapenem-3-carboxylate. This amorphous form of (1R,5S,6S)-2-[(6,7-dihydro-5H-pyrazolo[1,2-a][1,2,4]triazolium-6-yl)]thio-6-[R-1-hydroxyethyl]-1-methyl-carbapenem-3-carboxylate was then again dissolved in 0.4 ml water, and the resultant solution warmed to 40° C. to completely dissolve the (1R,5S,6S)-2-[(6,7-dihydro-5H-pyrazolo[1,2-a][1,2,4]triazolium-6-yl)]thio-6-[R-1-hydroxyethyl]-1-methyl-carbapenem-3-carboxylate. After storage under refrigeration conditions for a period of 3 hours, the sample was inspected and crystals were observed. The crystalline (1R,5S,6S)-2-[(6,7-dihydro-5H-pyrazolo[1,2-a][1,2,4]triazolium-6-yl)]thio-6-[R-1-hydroxyethyl]-1-methyl-carbapenem-3-carboxylate was washed with a small amount of 50% ethanolic solution in water, and the resultant crystals were dried at room temperature under a vacuum to yield 34 mg crystalline (1R,5S,6S)-2-[(6,7-dihydro-5H-pyrazolo[1,2-a][1,2,4]triazolium-6-yl)]thio-6-[R-1-hydroxyethyl]-1-methyl-carbapenem-3-carboxylate (75.6%).
The crystalline form of (1R,5S,6S)-2-[(6,7-dihydro-5H-pyrazolo[1,2-a][1,2,4]triazolium-6-yl)]thio-6-[R-1-hydroxyethyl]-1-methyl-carbapenem-3-carboxylate retains its potency over a prolonged period of time, whereas the amorphous form rapidly loses potency. For example, over a period of ten days, there is no appreciable loss of potency for the crystalline form, whereas the potency of the amorphous form is approximately 40% of the original value after a period of only ten days. | Methods and compositions are provided for controlling or preventing a bacterial infection which are based upon (1R,5S,6S)-2-[(6,7-dihydro-5H-pyrazolo[1,2-a][1,2,4]triazolium-6-yl)]thio-6-[R-1-hydroxyethyl]-1-methyl-carbapenem-3-carboxylate or a pharmaceutically acceptable salt thereof. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of co-pending German Patent Application No. 199 63 097.6 entitled “Zange zum Verpressen eines Werkstücks” filed on Dec. 24, 1999.
FIELD OF THE INVENTION
[0002] The present invention generally relates to pliers for crimping work pieces. More particularly, the present invention relates to pliers being operable with one hand and serving to apply great crimping forces onto the work piece in a few crimping steps.
BACKGROUND OF THE INVENTION
[0003] Pliers of this kind are also called crimping pliers or pressing pliers. Depending on the design of the work piece, especially in case of fittings, tubes and the like to be crimped, substantial pressing forces have to be applied onto the work piece. On the other hand, such work pieces may have comparatively great dimensions. Consequently, the crimping die being formed by two dies should have a great opening in the opened position of the pliers to be able to move the two dies over the work piece to be crimped in the opened position of the pliers. At the beginning of the closing movement of the pliers, there usually are no or at least no substantial pressing forces to be overcome. Contrarily, the pressing forces to be applied during the actual crimping movement of the work piece are substantial.
[0004] Pliers for crimping work pieces are known from German patent application DE 197 09 639 A1. The pliers include two handles being movable with respect to one another by one hand. A joint supports two pivot jaws. One of the two pivot jaws is connected to a stationary handle to form a stationary portion of the pliers. The other pivot jaw is pivotally connected to the stationary portion of the pliers by the joint. The pliers include separated dies forming a crimping die. A locking mechanism is arranged between the stationary handle and the movable handle, and it serves to reach a defined end position of the separated dies. The handles may first be reopened after one crimping process has been finished, after the end position has been reached and after the locking mechanism has released the handles. A pressure lever is arranged between the handles, and it is pivotally supported by the supporting joint. The pressure lever together with a section of the movable handle forms a toggle lever drive. This sole pressure lever is supported in a supporting joint including an eccentric surface allowing for an adjustment of the effective length of the pressure lever. The adjustability of the pressure lever serves to compensate work tolerances to exactly associative a closing position of the handles with an end crimping position of the pliers. It is also possible to adjust the pressure lever to eliminate wear and tear occurring at the connected joints or the dies. The two dies and the corresponding pivot jaws are designed as one piece. The fixed connection of the combined pivot jaw/die to the stationary handle is disadvantageous. The maximum applicable crimping forces are limited. Additionally, the preciseness of the finished crimped work piece highly depends on the realizable process tolerances with which the elements of the pliers are produced and which are used to assemble the pliers. Consequently, it is necessary to rework the dies of the pliers in many cases. The known pliers include handles made of molded plastic. These handles provide great stability at reduced exactness. Since the material flows, disadvantageous displacements of, for example, prearranged bores cannot be prevented. With the known pliers, the work piece is crimped in one crimping step.
[0005] Clamping pliers are known from German patent DE 25 59 656 B2. The clamping pliers include two handles being movable with respect to one another. Two pivot jaws are rotatable about a common joint. One of the pivot jaws is connected to a stationary handle to form a stationary pliers portion. The other pivot jaw is pivotally connected to the stationary pliers portion by the joint. A pressure lever is arranged between the two handles. The pressure lever is pivotal about a supporting joint and, together with a section of the stationary handle, it forms a toggle lever drive. To adjust the effective length of the pressure lever despite the fixed connection of the pressure lever at both ends at the handles, at least one of the supporting joints includes an eccentric tappet including different angle positions to adjust the kinematics of the clamping pliers, especially of the end position during the closing movement of the pivot jaws.
[0006] German patent DE 25 55 071 C2 additionally shows the application of a locking mechanism being arranged between the pressure lever and the stationary handle to reproducibly attain the defined end position of the pliers.
[0007] Clamping pliers including two handles being movable with respect to one another and two pivot jaws being pivotal about a common joint are known from U.S. Pat. No. 2,410,889. Each of the pivot jaws is connected to the associated handle to form a fixed pliers portion therewith. One of the two handles is divided into two portions each forming a lever to crimp the work piece in a few crimping steps. The two portions of the handle are interconnected by a joint to be pivotal with respect to one another. The portion of the handle to be held by the hand of the operator is lengthened in the direction towards the pliers head to extend beyond the joint to form a lever arm serving for transmission. A pulling lever is pivotally connected to the free end of the handle. The pulling lever encloses the two handles, and it is supported at the other handle not being divided. In this way, one portion of the divided handle is coupled to the other handle not being divided in each crimping step in different angle positions changing during the crimping process in a way that the end portions of the two handles facing away from the pliers head may be held and operated by the fingers of one hand in each angle position of each crimping step. Due to the division and support of the one handle at the other handle, there is an additional transmission of the actuation force to be applied by hand.
SUMMARY OF THE INVENTION
[0008] Briefly described, the present invention provides pliers for crimping work pieces. The pliers include a pliers head, a first pivot jaw being arranged in the region of the pliers head and a second pivot jaw being arranged in the region of the pliers head. A common joint pivotally connects the first and second pivot jaw. A first die is arranged at the first pivot jaw. A second die is arranged at the second pivot jaw. The first die and the second die together form a crimping die for crimping the work piece. A first handle is operatively connected to the first pivot jaw, and it includes an end portion facing away from the pliers head. The first handle is divided into at least a first portion and a second portion. A second handle is operatively connected to the second pivot jaw, and it includes an end portion facing away from the pliers head. The first and second handle are designed and arranged to be movable with respect to one another and to be operable to crimp the work piece in a few crimping steps. The second portion of the first handle is coupled to the first portion of the first handle in a plurality of different angle positions each corresponding to one crimping step in a way that the end portions of the first and second handle may be held and operated by the fingers of one hand of the operator in each angle position of each crimping step. A locking mechanism is designed and arranged to attain a defined closed position of the first and second die. A toggle lever drive includes a plurality of supporting joints and a pressure lever operatively connecting the first and second handle. The pressure lever is supported by the plurality of supporting joints.
[0009] The present invention is based on the concept of designing the pliers user friendly and appropriate for applying great crimping forces. It is desired to ensure that the pliers may be used and operated by one hand. This means that the handles need to be designed in a way that they may be grasped by the fingers of one hand of the user already at the beginning of each crimping step and that they may be pressed towards each other during the crimping stroke. On the other hand, it is desired to be able to apply crimping forces of up to 3 to 5 tons and more onto the work piece, even during overhead or narrow working conditions.
[0010] In the prior art, it is only possible to apply such great crimping forces with crimping tools including an electrical drive or a hydraulic drive. The pliers according to the present invention are designed to attain these great crimping forces by realizing a plurality of crimping steps or stages.
[0011] At least one of the handles is divided into at least two portions each forming a part of the handle. Each part of the handle forms a lever arm. This sum of the lengths of the two lever arms corresponds approximately to the length of the lever arm of the other handle. The two portions of the divided handle are interconnectable and they support each other, respectively, in a different angle position in each crimping step. Thus, the end portions of the two handles facing away from the pliers head may be grasped by the fingers of one hand of the operator in each angle position of each crimping step. The crimping steps result from a change of the angle position of the portions of the divided handle with respect to each other. Generally, it is sufficient to realize two angle positions and, consequently, two crimping steps. However, in case of great requirements, there is the possibility of providing a few crimping steps one after the other. Realizing a few crimping steps means to provide at least two crimping steps up to approximately four crimping steps. In combination with a toggle lever drive, it is ensured that the part of the handle of the divided handle facing away from the pliers head is progressively dislocated with respect to the geometry of the toggle lever drive, especially with respect to the dead center of the toggle lever drive, in each crimping step. The ratio of transmission of the toggle lever drive is used during each crimping step. In this way, the necessary operating forces to be applied manually are kept low.
[0012] The novel pliers have a short structural length and a comparatively little weight. The pliers are at least operable by one hand of the user in the crimping steps. This means that the free end portions of the handles at the beginning of each crimping step are located in a position in which the distance between them is less than approximately 110 mm. However, the operator may use both hands to increase the hand forces. In case three crimping steps are realized, both handles may be divided.
[0013] The locking mechanism is operable located between the fixed handle and the pivot jaw being pivotal about the joint. The locking mechanism does not transmit crimping forces, but it only serves to reproducibly reach a defined end position of the dies and to attain crimping results of constant quality at a series of work pieces having the same dimensions. The arrangement of the locking mechanism in the pliers is of substantial importance. The jack of the locking mechanism is resiliently movable but stationary. The jack may be arranged at the fixed handle, the locking mechanism preferably including a tooth segment including a low number of teeth having a comparatively great pitch. The tooth segment is arranged at the movable pivot jaw, or at least it is connected thereto. With this arrangement, the pliers are adjustable such that the end position is safely attained in the last crimping step, and that an especially great crimping pressure is reproducibly applied before the pliers may be reopened, for example by a spring. In the completely opened position of the pliers and after the work piece to be crimped has been inserted into the pliers, the pliers may usually not be operated by one hand. However, this is no disadvantage since no crimping forces are applied in this position, but the dies do only have to be closed to surround the work piece. The crimping forces are realized during the crimping steps.
[0014] The first portion and the second portion of the divided handle may be designed and arranged to be automatically adjusted to reach the different angle positions between the crimping steps. This means that that the second angle position between the portions of the divided handle is automatically reached and locked after the first crimping step has been finished. It is also possible to choose a semi-automatic design that may depend, for example, on an opening stroke of the handle after the first crimping step. It is preferred to use a spring for this arrangement.
[0015] However, the first portion and the second portion of the divided handle may also be designed and arranged to be manually adjustable to reach the different angle positions between the crimping steps. Especially in combination with such a manual adjustment of the two angle positions of the two portions of the divided handle, there are a number of different design possibilities for the person with skill in the art. It is especially simple to design the portions of the divided handle in a way that they may be put together in two different angle positions. A locking mechanism including a ball for securing the positions of the two portions of the divided handle may be used. Additionally or alternately, an elongated hole connection may be arranged to act between the portions of the divided handle to make sure that the portion of the divided handle forming the free end is captivated at the pliers. An elongated hole connection is to be understood as a device including an elongated hole or opening and a pin or bolt engaging the elongated hole.
[0016] Another possibility is to interconnect the two portions of the divided handle of the pliers by a joint, on the one hand, and by an elongated hole connection, on the other hand, to be adjustable to alternately reach the two angle positions with respect to each other. The elongated hole connection extends in a transverse direction with respect to the direction of main extension of the two portions of the handle. The elongated hole is located at one portion of the divided handle. A transverse pin or bolt or the like is located at the other portion of the handle. The elongated hole may also be designed as a gate including a plurality of offsets. A locking bolt may be movably guided in one portion of the divided handle, the locking bolt being subject to the pressure of a spring. A stop cooperating with the locking bolt may be arranged at the other portion of the two-part handle. In this way, the angle position being associated with the second crimping step is determined in a semiautomatic fashion when the opening stroke being conducted after the first crimping step has been finished is sufficient.
[0017] The pliers may also include a first elongated hole connection and a second elongated hole connection. The two elongated hole connections alternately connect the two portions of the divided handle in two different angle positions. Both elongated hole connections are designed and arranged to allow for a limited movement of the two portions of the handle with respect to one another in their direction of main extension. One of the two elongated hole connections is designed and arranged to allow for a limited movement of the portions of the handle in a direction transverse to their direction of main extension.
[0018] It makes sense to arrange the pressure lever to be connected to the portion of the divided handle facing the pliers head. In this way, the same ratio of transmission prevails in each crimping step. Generally, the division or the separation of the divided handle may be realized in way that the portion of the handle facing the pliers head has a lever length being a little less than the lever length of the other portion of the divided handle forming the free end portion.
[0019] The locking mechanism may include a tooth segment being fixedly connected to the portion of the divided handle facing the pliers head to be commonly rotated therewith and a locking jack being supported on the pressure lever. With this arrangement, the locking mechanism is arranged at an appropriate location defining the end position of the dies of the pliers. In combination with the use of an eccentric bolt for supporting the pressure lever of the toggle lever drive, the play or looseness prevailing in the joints and the corresponding work tolerances of the elements of the pliers may be adjusted to be very small.
[0020] Other features and advantages of the present invention will become apparent to one with skill in the art upon examination of the following drawings and the detailed description. It is intended that all such additional features and advantages be included herein within the scope of the present invention, as defined by the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] The invention can be better understood with reference to the following drawings. The components in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the present invention. In the drawings, like reference numerals designate corresponding parts throughout the several views.
[0022] [0022]FIG. 1 is a view of a first embodiment of the pliers in their opened position directly after the crimping process has been finished.
[0023] [0023]FIG. 2 is a view of the pliers of FIG. 1 at the beginning of the first crimping step.
[0024] [0024]FIG. 3 is a view of the pliers of FIG. 1 at the end of the first crimping step.
[0025] [0025]FIG. 4 is a view of the pliers of FIG. 1 at the beginning of the second crimping step.
[0026] [0026]FIG. 5 is a view of another exemplary embodiment of the pliers at the end of the second crimping step.
DETAILED DESCRIPTION
[0027] Referring now in greater detail to the drawings, FIG. 1 illustrates pliers including handles 1 and 2 . The handle 1 is fixedly connected to a pivot jaw 3 to be commonly rotated and such that these two elements form a stationary portion of the pliers. The pivot jaw 3 and the handle 1 may also be designed as one piece. The handle 1 is also referred to as stationary handle, although, for an activation of the pliers, it is only important that there is a relative movement of the handles 1 and 2 with respect to one another. In addition to the stationary pivot jaw 3 , there is a movable pivot jaw 4 being pivotally connected to the stationary portion of the pliers 1 , 3 by a joint 5 . The stationary handle 1 may be designed as a semi shell or to have a plate design such that its legs or plates extend approximately symmetrically to the plane of main extension 19 of the pliers. A pin 6 extends through the legs or plates, the movable pivot jaw 4 being designed and arranged to be pivotal with respect to the stationary pivot jaw 3 about the axis 7 of the pin 6 . A crimping die 8 is located at the pivot jaws 3 and 4 . The crimping die 8 may be designed to be replaceable or to form one piece with the pivot jaws 3 , 4 . In the exemplary embodiment of FIG. 1, the crimping die 8 is formed by two dies being designed in the form of semi shells. The semi shells are removeably or replaceably inserted into the pivot jaws 3 , 4 . The axial length of the semi shells perpendicular to the plane of main extension 19 also forming the plane of illustration covers the length of a union stem onto which, for example, a tube is to be connectingly and sealingly crimped. Preferably, the axis 9 (FIG. 5) of the crimping die 8 is to be located close to the joint 5 , meaning at a distance between the axis 7 and 9 being chosen to be as small as possible.
[0028] The movable pivot jaw 4 being associated with the movable handle 2 is enlarged in a lateral direction with respect to the stationary handle 1 to arrange a first support joint 10 , the axis 11 of which being formed by a pin 12 . The movable handle 2 engages the pin 12 .
[0029] A second support joint 13 is arranged at the movable handle 2 , the support joint 13 being formed by a pin 14 having an axis 15 . A pressure lever 16 being arranged between the handles 1 and 2 is pivotally supported by the pin 14 . The other end of the pressure lever 16 is pivotally supported in a third support joint 17 . The support joint 17 may be formed by an eccentric pin 18 . The eccentric surface of the eccentric pin 18 supports the pressure lever 16 . The eccentric pin 18 is rotateably connected to the stationary handle 1 . The eccentric cam is of the eccentric pin 18 is dislocated with respect to the pressure lever 16 during rotation. Thus, eccentricity changes its position. The eccentric pin 18 at its circumference includes a plurality of notches to change eccentricity and the effective length of the pressure lever 16 .
[0030] The stationary handle 1 is designed as a continuous lever. Thus, the length of the lever of the stationary handle 1 corresponds to the distance between the joint 5 and its free and portion 20 . The movable lever 2 is divided into two portions 21 and 22 having approximately the same lever length. The total lever length of the movable handle 2 extends from the joint 10 to the end portion 23 of the movable lever 2 . In the close position of the pliers, the end portion 23 of the movable handle 2 is located adjacent to the end portion 20 of the stationary handle 1 .
[0031] The two portions 21 and 22 of the movable lever 2 may support one another in at least two relative positions or angle positions. Each angle position is associated with a crimping step. However, there may be more than two angle positions. To emphasize the basic design of the novel pliers, the drawings only show at exemplary embodiments in which the movable handle 2 is divided into two portions 21 and 22 being lockable with respect to one another in two different angle positions. Additionally, in the illustrated embodiments, the novel design of the pliers has only been applied to the movable handle 2 . It is to be understood that the novel division or separation may also be realized exclusively at the stationary handle 1 , or at both handles 1 and 2 at the same time.
[0032] In the exemplary embodiment of the pliers according to FIG. 1, the two portions 21 and 22 are designed and arranged to be interconnectable in two different angle positions by two elongated hole connections 24 and 25 . The elongated hole connection 24 includes an elongated hole 26 and a transverse bolt 27 . The elongated hole 26 substantially extends approximately in the direction of main extension of the handle 2 . The elongated hole connection 25 also includes an elongated hole 28 and a transverse bolt 29 . The elongated hole 28 includes a first portion extending approximately in the direction of main extension of the handle 2 and being located in alignment with or parallel to the elongated hole 26 . However, the elongated hole 28 additionally includes a second portion extending substantially transverse to the direction of main extension of the lever 2 . The distribution and the arrangement of the transverse bolts 27 and 29 , on the one hand, and of the elongated holes 26 and 28 , on the other hand, with respect to the portions 21 and 22 of the handle 2 are variable. For example, the distribution and the arrangement may be changed, as it is to be seen from a comparison of the embodiments of the pliers of FIGS. 1 and 2. For example, when the transverse bolts 27 and 29 are located on the portion 21 (FIG. 1), and the elongated holes 26 and 28 are located the portion 22 , a first angle position between the portions 21 and 22 is possible. In this first angle position, both portions 21 and 22 enclose an angle being a little less than 180 degrees. The angle being less than 180 degrees is located on the outside of the movable handle 2 , as it is illustrated in FIG. 1. This angle position or relative position of the two portions 21 and 22 of the handle 2 is the one occurring at the end of the crimping process of a work piece (FIG. 5). This angle position is also taken by the two portions 21 and 22 during the entire second crimping step (FIGS. 4 and 5).
[0033] In the completely opened position of the pliers according to FIG. 1, the dies of the crimping die 8 are located at the greatest distance with respect to one another. Consequently, a crimped work piece may be easily taken out off the pliers, and a work piece to be crimped may be easily inserted into the pliers. Before this or after this, the other angle position between the portions 21 and 22 at the handle 2 is being adjusted, as it is also necessary at the beginning of the first crimping step (FIG. 2). The angle being enclosed between the portions 21 and 22 and being a little less than 180 degrees is now located on the other side of the portions 21 and 22 . To reach the second angle position according to FIG. 2—starting from the angle position according to FIG. 1—it is only necessary to move the portion 22 with the elongated holes 26 and 28 with respect to the transverse bolts 27 and 28 according to arrow 30 about the possible stroke and in an inward direction, and to pivot the portion 22 about the transverse bolt 27 forming a joint such that the portions 21 and 22 take the relative position as illustrated in FIG. 2. In case the arrangement of the elongated holes 26 and 28 on the portion 22 is inverted, as this is illustrated in FIG. 2, the portion 22 also has to be pressed in the direction according to arrow 30 . When the arrangement of the transverse bolts 27 and 29 , on the one hand, and of the elongated holes 26 and 28 , on the other hand, is inverted on the portions 21 and 22 , there is a corresponding necessity of movement.
[0034] [0034]FIG. 2 illustrates the relative position of the portions 21 and 22 of the handle 2 with respect to the handle 1 at the beginning of the first crimping step. The work piece (not illustrated) has already been inserted into the crimping die 8 , and the pliers have been located to surround the work piece, respectively, and they have been moved from the opened position according to FIG. 1 into an intermediate position in which the first crimping step may start. It is now assumed that the dies of the crimping die 8 do surround the deformable work piece at this moment for the first time. Consequently, it will be necessary at the beginning of the first crimping step to provide the crimping forces necessary for deforming the work piece. However, these necessary crimping forces may have an extremely great value. The angle position between the portions 21 and 22 at the handle 2 , as illustrated in FIG. 2, is chosen, dimensioned and arranged such that the free end portions 20 and 23 of the handles 1 and 2 are arranged at a distance being less than approximately 110 mm. This distance is small enough to enable the operator of the pliers to grasp, hold and operate the two handles 1 and 2 in the region of the end portions 20 and 23 with the fingers of one hand.
[0035] After the first crimping step has been finished, meaning the two handles 1 and 2 have been pressed towards each other, as illustrated in FIG. 3, the pliers are moved into the position of FIG. 4 to prepare the second crimping step. The portion 22 of the handle 2 is being pivoted in an opening sense between the positions of FIGS. 3 and 4 about the transverse bolt 27 . It is slightly pulled out in a direction opposite to arrow 30 until the locking position of the portions 21 and 22 according to FIG. 4 has been reached. In this position, the two end portions 20 and 23 of the handles 1 and 2 are located at a distance with respect to each other being less than approximately 110 mm, again. Consequently, the operator may also grasp, hold and operate the handles 1 and 2 with the fingers of one hand to conduct the second crimping step. However, the operator may additionally use the second hand to increase the applied crimping force if necessary and adequate.
[0036] The end of the second crimping step and, consequently, the complete desired crimping process of the work piece, has been reached after the handles 1 and 2 have taken the end position of FIG. 5.
[0037] The pliers include a locking mechanism 31 to reproducibly coordinate the movement of the crimping process including the two crimping steps including the prearranged closing of the crimping die 8 , and to reliably attain the end position of the closing position according to FIG. 5 starting from the completely opened position according to FIG. 1. The locking mechanism 31 includes a tooth segment 32 and a locking jack 33 . The tooth segment 32 may be fixedly connected to the portion 21 of the movable handle 2 to be commonly rotated therewith. However, the tooth segment 32 may also be designed as one piece with the portion 21 , or it may be connected to the movable pivot jaw 4 . There also are a number of possibilities for the design and arrangement of the locking jack 33 . In the illustrated exemplary embodiment, the locking jack 33 is supported at a bolt 34 to be freely rotatable. The bolt 34 is arranged at the pressure lever 16 . The locking jack 33 includes a ratchet 35 . The locking jack 33 being located on the bolt 34 to be freely rotatable in both directions is subject to the force of a spring 36 . When the ratchet 35 is free from engagement, the spring 36 provides for the starting position of the locking jack 33 according to FIG. 1. The spring 36 may be connected to an opening being located at the pressure lever 16 . The ratchet 35 of the locking jack 33 cooperates with the teeth of the tooth segment 32 in both directions of movement. A free pivot portion is arranged at each end of the teeth of the tooth segment 32 .
[0038] The operation and the effects of such a locking mechanism 31 are well known in the art. The locking mechanism 31 already engages during the closing movement of the pliers and of the crimping die 8 , respectively, about the work piece, as this is shown by the position according to FIG. 2. Then, it is no longer possible to open the pliers. Instead, the entire crimping process including the two crimping steps has to be conducted. In this way, it is ensured that the two crimping steps are realized in the desired and predetermined order one after the other, and as it makes sense and as it is necessary to correctly crimp the work piece. The relative positions of the elements of the locking mechanism 31 are to be seen from the series of drawings according to FIG. 1 through FIG. 5. Additionally, the association of these elements with the two crimping steps is to be seen from the drawings according to FIG. 1 through FIG. 5.
[0039] [0039]FIG. 5 does not only show the end position of the elements of the novel pliers at the end of the second crimping step or stage, but also the another exemplary embodiment of the novel pliers. The portion 21 of the divided handle 2 is designed as a two-piece element for reasons of manufacture. The pliers include a stop element 37 including two pins 38 and 39 by which it is fixedly connected to the portion 21 to be commonly rotated therewith. The stop element 37 includes a step or a stop 40 for the engagement with a locking pin 41 being arranged on a spring 42 in the direction of the extension of the portion 22 of the handle 2 . An actuation button 43 allows for the manual pressing of the locking pin 41 back against the force of the spring 42 . The portions 21 and 22 of the movable handle 2 are interconnected by a joint 44 and an elongated hole connection 45 . The elongated hole connection 45 includes a transverse bolt 46 and an elongated hole 47 . It is to be seen from FIG. 5 that the elongated hole 47 extends approximately transverse to the direction of main extension of the handle 2 . For example, the transverse bolt 46 is arranged on the portion 22 of the handle 2 . The elongated hole 47 is arranged on the stop element 37 .
[0040] The exemplary embodiment of the novel pliers according to FIG. 5 makes it possible to operate the pliers in a semi-automatic fashion. During the first crimping step, the crimping forces acting between the portions 22 and 21 are transmitted by the joint 44 and the elongated hole connection 45 , while the locking pin 41 is supported at a face 48 of the stop element 37 under the force of the spring 42 . After the first crimping step has been finished, only an opening stroke between the handles 1 and 2 has to be realized until the locking pin 41 gets free from contact to the face 48 , and it is capable of engaging the stop 40 due to the force of the spring 42 , as this is illustrated FIG. 5. Then, the second crimping step may take place. The locking mechanism 31 is designed and arranged to be coordinated with the semiautomatic operation of the novel pliers.
[0041] Many variations and modifications may be made to the preferred embodiments of the invention without departing substantially from the spirit and principles of the invention. All such modifications and variations are intended to be included herein within the scope of the present invention, as defined by the following claims. | Pliers for crimping work pieces include a pliers head and two pivot jaws ( 3, 4 ) being arranged in the region of the pliers head. A common joint ( 5 ) pivotally connects the two pivot jaws ( 3, 4 ). Two dies forming a crimping die ( 8 ) for crimping the work piece are arranged at the two pivot jaws ( 3, 4 ). Two handles ( 1, 2 ) are connected to the pivot jaws ( 3, 4 ), and they each include an end portion ( 20, 23 ) facing away from the pliers head. At least one of the handles ( 1, 2 ) is divided into at least two portions ( 21, 22 ). The handles ( 1, 2 ) are designed and arranged to be movable with respect to one another and to be operable to crimp the work piece in a few crimping steps. One portion ( 22 ) of the divided handle ( 1, 2 ) is coupled to the other portion ( 21 ) in a plurality of different angle positions each corresponding to one crimping step in a way that the end portions ( 20, 23 ) may be held and operated by the fingers of one hand of the operator in each angle position of each crimping step. A locking mechanism ( 31 ) is designed and arranged to attain a defined closed position of the dies. A toggle lever drive includes a plurality of supporting joints ( 13, 17 ) and a pressure lever ( 16 ) connecting the two handles ( 1, 2 ). The pressure lever ( 16 ) is supported by the plurality of supporting joints ( 13, 17 ). | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to packaging techniques for computer discs, and is more particularly concerned with the provision of a protective canister for transporting the computer discs.
2. Description of the Prior Art
Although the present invention provides a protective canister which was designed for a particular size of disc, for example a 51/4" rigid disc, such as aluminum, the package may be resized for other sizes of discs.
Presently, computer discs are milled at a first facility and then undergo further processing, including for example, polishing and receiving an application of magnetic material for storing information, usually at a second facility. During the entire process, the disc may be protected from contamination. This is particularly true during packaging and shipment of the disc from one facility to another.
A previous package comprised a rigid base having a plurality of spaced posts extending therefrom sized to closely receive the central apertures of the discs to form a plurality of stacks of discs with flat spacer rings therebetween. A second rigid base is secured to the free ends of the post and the resultant structure is sealed in a cardboard box. The bases and the posts were usually wood. It has been determined, however, that the paper and wood generate particulate matter which contaminates the discs and makes them useless.
It is general practice to mill and package the discs in clean rooms; therefore, contamination can only come from mishandling or from the package itself.
SUMMARY OF THE INVENTION
It is therefore the object of the present invention to provide a package for transporting computer discs, which package provides physical protection in a contamination-free environment.
According to the invention, the package comprises a cylindrical tube having open ends which are closed by end caps. The diameter of the tube is greater than the outer diameter of the disc, so as to provide sufficient spacing therebetween. The end caps are provided with resilient latches which engage latch apertures in the tubes. The latches may be flexed for disengagement; however, inasmuch as the canister will probably not be used again, the latches are joined to the end caps by frangible sections so that the same may simply be broken away. Releasably secured to the end caps and positioned thereby coaxial with the longitudinal axis of the tube is a central post, here also in the form of a hollow tube. A post mount in each end cap frictionally engages and secures the central post.
Concentric with the central post, and provided on each end cap, is a platform for engaging the last spacer ring on each end of a stack of alternate computer disc and rings. When the stack is loaded and the end caps latched to the outer tube, the platforms clamp the stack therebetween.
According to a particular feature of the invention, the entire package is constructed of materials which do not generate particulate matter. Such materials may include hydro-carbon-based polymers such as polystyrene, polypropylene, ABS plastics and the like.
A disc of the type mentioned above stores information on tracks which are spaced so that there are 900 tracks per inch, for example. Therefore, the contamination provided by the spacer rings must be held to a minimum. In a first embodiment, the spacer rings contact a small surface area, for example 0.250" about the central aperture. Even this small surface area will constitute approximately 450 tracks of loss data storage when one considers both sides of the disc. In a preferred embodiment of the invention, there is essentially zero loss in that the spacer ring is constructed to be complemental to the inner diameter of the central aperture and a bevel surface which extends between a main surface and the inner diameter of the central aperture.
The spacer of the first embodiment is a flat ring of, for example, polypropylene, whereas the spacer of the preferred embodiment is a ring which supports a plurality of arcuate projections, alternate ones of which face in opposite directions along the direction of the axis of the post. Each of the projections comprises an L-shaped cross section as viewed in radial section with a first leg for entering and engaging the inner diameter of a central aperture and a second leg with a bevel surface matching that of the bevel surface of a disc. Therefore, the main surface of a disc is not contacted and is therefore not contaminated.
According to another feature of the invention, loading and unloading is facilitated by providing minimum friction between the spacers and the central post while maintaining centering of the spacers. This is accomplished by providing a surface of the spacer rings in the form of raised lands spaced about the inner surface. The lands may be raised, for example, 0.005-0.010" so that the inner diameter is reduced on the order of 0.010-0.020".
In order to further protect the disc during shipment, the entire loaded canister may be sealed, for example by enclosing the same in shrink film. Afterward, more conventional packaging may be employed.
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 pictorial representation of a canister for protecting computer discs;
FIG. 2 is a sectional view taken along the line II--II of FIG. 1 and illustrates a loaded canister using the previous style of spacer, but useable with a new style of spacer as shown in FIG. 7;
FIG. 3 is a sectional view taken generally along the line III--III of FIG. 2;
FIG. 4 is an enlarged fragmentary sectional view illustrating the alternate stacking of the previous style spacers and discs on the central post;
FIG. 5 is a pictorial representation of the use of an end cap as a stand for the central post for loading and unloading computer discs and spacer rings;
FIG. 6 is a sectional view similar to that of FIG. 2 and illustrating the utilization of a preferred embodiment of a spacer ring;
FIG. 7 is an enlarged fragmentary sectional view taken generally along the line VII--VII of FIG. 6;
FIG. 8 is an elevation of the spacer ring employed in the structure of FIG. 6;
FIG. 9 is a top view of the spacer of FIG. 8;
FIG. 10 is a fragmentary view, taken generally along the line X--X of FIG. 9, illustrating the inner surface structure of the preferred spacer ring;
FIG. 11 is a view, similar to that of FIG. 3, showing an end cap for receiving two different sizes of posts to accommodate discs having different sizes of central apertures;
FIG. 12 is a fragmentary sectional view taken along the line XII--XII of FIG. 11; and
FIG. 13 is a fragmentary sectional view taken along the line XIII--XIII of FIG. 11.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1-4, a protective canister is generally illustrated at 10 as comprising a hollow tube 12 and a pair of end caps 14 which releasably engage the tube 12, as will be discussed in detail hereinbelow.
At each end of the tube 12 is a plurality of spaced latch apertures 16 each including a latch edge 18 which engages a hook surface 20 of a latch 15 when an end cap is in position. As the end cap is moved into position, a ramp surface 17 engages the end of the canister and flexes the latch 15 outwardly as the end cap is moved into place. When the end cap is in place, as illustrated, the surfaces 18 and 20 are engaged.
In the central area of an end cap 14 is a pair of molded structures for supporting the central post 34, here a hollow tube, and for supporting a plurality of discs and spacers as alternate members of a stack. The central post 34 is placed over and receives a post mount 28 which includes a ring body 30 and a plurality of radially-extending friction reducing and strengthening fins 32. The post 34 is centered by this structure and retained in a friction fit.
Concentrically about the post mount 28 is a platform 22 which comprises a ring 24 and a plurality of radially-extending fins 26 which strengthen the structure and support the stack.
As is evident from FIG. 2, the end caps are of identical structure so that the post 34 is held fixed in a central position. As is also apparent, the tube 12 is of larger inner diameter than the outer diameter of the disc 36 so that there is no contact therebetween when the package is completed. Furthermore, the platforms 22 serve to clamp the stack therebetween with each disc having a spacer 40 on each side thereof. As is evident, a spacer contacts an adjacent disc over a small surface area about the central aperture.
The tube 12 could have one end sealed and one end open to be closed with an end cap. In such a structure, the spacers and discs would be alternately loaded over the center post 34, and the end cap would then be used to close the canister. However, and as illustrated in FIG. 5 the canister may be loaded by employing an end cap 14 as a base or stand for the post 34. The spacers and discs may then be loaded over the post and the tube 12 and the other end cap 14 may then be placed over the stack with care being taken to avoid contact between the tube 12 and the discs 36.
Although the spacer 40 contacts a disc 36 over but a small surface area so that the same become contaminated and unusable in this small area for purpose of data storage, such an area constitutes a great loss of data capacity. In order to at least minimize and preferably eliminate this loss, the minimization or elimination of contamination in this area is desirable. Therefore, we have taken steps to accomplish the same and present a canister for this purpose in FIGS. 6-9.
Turning now to FIGS. 6-9, a canister with a preferred embodiment of a spacer is illustrated in which the hollow tube 12, the end caps 14, the post 34, the post mount 28 and the platform 22 are the same as in FIG. 2. The difference is in the provision of a spacer 46 which has a shaped structure so as to avoid contact with the main surfaces of the discs. As best seen in FIG. 7, a pair of bevel surfaces 48 extend from respective main surfaces of a disc to the inner diameter of the central aperture 38. The angle of bevel may be, for example, 21° . We now provide a spacer 46 which contacts only the inner diameter of the disc and the bevel surface of the disc so that the entirety of each main surface is available for data storage. The preferred spacer 46 is best seen in FIGS. 8 and 9 as comprising a ring 50 and a plurality of arcuate projections 52 on each side of the ring 50. Each arcuate projection 52 is generally L-shaped as viewed in radial section and comprises a first leg 54 which extends into and engages the inner diameter of the aperture 38 and a second leg 56 shaped complemental to and for engaging a bevel surface 48. Therefore, as the stack is constructed, only the inner diameter of an aperture and the bevels are contacted by any structure and the main surfaces of the discs remain free from contamination.
It should be noted that the first leg 54 is spaced so as to nest between the outer surface of the central post 34 and the body of the ring 50 and to abut the adjacent spacer at the body of its ring.
Referring to FIGS. 9 and 10, the inner surface of the ring 50 is provided as a profiled surface and includes a plurality of spaced lands 58 which provide minimum frictional contact with the center post 34 and maintain centering of the spacer with respect to the center post. Therefore, loading and unloading are facilitated.
After a canister is loaded, the discs are further protected from external contaminant particles by enclosing the entire canister in a shrink film.
Afterward, more conventional packaging techniques may be employed for transporting the canisters to another facility for further processing into completed discs.
At such a further facility, the discs may be removed in a reverse procedure by unlatching the end caps and the hollow tube 12. If the canister is not to be reused and this is usually the case, the latches may be provided as frangible structures. Returning to FIGS. 1 and 2, each latch hook is illustrated as comprising a tab 42 which is positioned spaced from the hollow tube 12 so that it may be grasped between a thumb and index finger, for example, and bent outwardly. Each latch hook is connected to its end cap by a pair of small frangible sections 44 which break upon flexing of the hook beyond the yield point of the material.
In summary, we have provided a canister for protecting computer discs. In one embodiment, the canister employs spacers which contact only small surface areas about the apertures of the computer discs. In a preferred embodiment, we have provided that the small surface area be a bevel surface about the aperture, which bevel surface is not employed for data storage, so that the entire main surfaces of each disc are available for data storage.
Referring now to FIGS. 11, 12 and 13, a further embodiment of an end cap is illustrated for accommodating a central post of a first size and a central post of a second size so that the canister may be employed for protecting and transporting discs having different sizes of central apertures. For example, a 3.5" disc may have the same aperture as the above-discussed 5" disc, for example 11/2" diameter, or a smaller aperture diameter of, for example, 3/4" diameter. In order to be able to protect and transport both types of discs, a central post of a corresponding diameter may be selected and mounted to the end caps. It has been determined that during the extrusion process of the hollow tubes which form the central posts, there is a greater control of the outer diameter. In this embodiment, therefore, it is the outer diameter of the tube which is engaged by the supporting structure. In this embodiment, a first structure 64 is provided for receiving a tube of a first diameter and a second structure 66 is provided for receiving a tube of a lesser diameter.
The structure 64 comprises a ring 68 extending from the end cap 62 and a plurality of radially-extending members 72 whose free ends define the outer diameter of the tube to be received. The second structure 66 similarly comprises a ring 74 having a plurality of radially inwardly extending members 76 whose free ends define the outer diameter of the tube to be received. As illustrated, a plurality of strengthening members 70 may be provided; however, the first and second structures 64 and 66 should provide suitable rigidity.
As illustrated in FIG. 12, the members 72 are recessed and beveled so as to receive a corresponding portion of the new style of spacer ring.
A spacer ring of the same design may be employed on the second structure 66; however, it is not intended that this ring be received within the structure 66, but rather rest on top of the structure 66.
Turning once again to FIGS. 1, 3 and 5, and to FIG. 11, the cap 14 is illustrated as comprising a plate having a peripheral edge extending therefrom, the peripheral edge including a plurality of recesses 60. The recesses 60 are provided spaced about the cap so that one may have access to the last disc of the stack when the disc are unstacked for further processing.
Although we have described our 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 thereof. We therefore intend to include within the patent warranted hereon all such changes and modifications as may reasonably and properly be included within the scope of our contribution to the art. | A protective canister for computer discs comprises a hollow tube and a pair of end caps for closing the tube and fixing a central post therein. A stack of alternate computer discs and spacers having aligned central apertures is loaded onto the center post and clamped in the canister by way of a pair of platforms carried by the end caps about the central post. The elements of the canister are preferably constructed from hydrocarbon-based polymers and, after loading, the canister is sealed in shrink film so that the discs are protected in an environment which is free of particulate matter. | 8 |
This application is a continuation, of application Ser. No. 07/569,360, filed Aug. 17, 1990, now abandoned.
RELATED APPLICATIONS
This application is related to U.S. patent application Ser. No. 07/531,493, filed May 30, 1990, entitled "A System and Method For Database Management Supporting Object-Oriented Programming", by Bannon et al., which is incorporated by reference herein.
TECHNICAL FIELD OF THE INVENTION
This invention relates generally to the field of computer databases, and more particularly to a transaction and version management system.
BACKGROUND OF THE INVENTION
Computer databases are widely used by businesses to access data for performing business transactions, such as making a savings account deposit or a withdrawal, reserve or purchase an airline ticket, buy or sell a security, etc. Each of these business transactions rely on the integrity of the data in the databases; i.e., the balance in the savings account must reflect the correct amount after the deposit or withdrawal. While conventional database applications generally comprise "short transactions" running for a few milliseconds, new applications, such as computer-aided design may include "long" transactions, which have the possibility of running for days, or even for weeks.
The databases described in the business transactions above are generally accessed and modified by multiple concurrently-run computer programs. Each of these concurrently-run programs (hereinafter, referred to as "transactions") comprise a plurality of operations on the database elements. In order to increase efficiency, the operations of the concurrently-run transactions are interleaved. The outcome of interleaved transactions, of course, should be the same as the outcome of running the transactions serially. A system which promotes this property is referred to as "serializable."
Without some control mechanism, concurrent transactions may result in one transaction's operations affecting another transaction's operations by accessing (reading and/or writing) the same element of the database. Such interferences may result in erroneous data in the databases; i.e., they may affect the "consistency" of the database. Protocols presently exist to protect the consistency of the database while it is accessed by concurrently running transactions. One such protocol is a static two-phase locking scheme. The static two-phase locking scheme provides "locking" of all the database elements to be accessed by a transaction, before any operation of the transaction is performed, thus preventing any other transactions from accessing and altering the database elements. The database elements are "unlocked" immediately following the end of the transaction. If a transaction "commits" after its last operation, all database elements retain their values as updated by the transaction. If a transaction is "aborted", all database elements return to their values before as they were before the transaction.
A similar protocol, a dynamic two-phase locking scheme, locks each data item to be accessed by the transaction immediately prior to each accessing operation, and then releases the locks on all the data items immediately following the last operation of the transaction.
Both the static and dynamic two-phase locking scheme exhibit a first phase, during which locks are acquired on required data items, and a second phase, during which all the locks are released. By locking the database elements, a form of scheduling is achieved, since only the transactions that have locked all of their required data items are executed to completion. Other transactions which require access to database elements locked by another program, must wait until the lock is released. In other words, the locking scheme in effect puts concurrently-run programs in serial execution form at the cost of reducing throughput. Thus, if a long transaction locks an element needed by one or more short transactions, the short transactions may wait days or weeks before executing.
The two-phase locking schemes are referred to as "pessimistic," since they assume that an inconsistency will result between two or more concurrent transactions. "Optimistic" concurrency control allows a transaction to proceed as if there were no conflict, and performs a validation check at the time of commit of the transaction. The system assigns a unique timestamp to a transaction when it first begins to run. The transaction has a consistent view of the database during its execution; at commit time, the database systems checks, based on the timestamp, whether this consistent view of the database has changed between the start and finish of the transaction. If the consistent view still holds, the transaction is committed; if not, the transaction is aborted.
This protocol also has disadvantages, particularly with long transactions, since a transaction will run to its end before the determination is made whether it will be aborted or committed. If aborted, the entire transaction will need to be re-executed, which is an inefficient use of processing time, especially when a long transaction must be re-executed.
Further, present day databases do not adequately provide for cooperative efforts between multiple users.
In a cooperative transaction, the work done by the team should be an atomic (indivisible) transaction. Also, members of the team should be able to view and modify the other team member's intermediate results. Accordingly, a need has arisen for a consistency control scheme that increases throughput of both long and short transactions and supports cooperative efforts between multiple users.
SUMMARY OF THE INVENTION
In accordance with the present invention, a database is provided which substantially eliminates or prevents the problems associated with prior databases.
In the database of the present invention, each version of an element of the database is represented by a unique identifier, a timestamp, a branch name and a value. A new version of an element is created in response to an operation which would modify the element. Thereafter, the value of the new version of the element is modified responsive to said operation.
Each element of the database may have multiple versions; the versions are partitioned into branches and versions of a branch are ordered linearly according to their timestamps. Branches are themselves timestamped and related to each other by a version graph. An object graph in the database may be represented independent of branches and versions.
The database of the present invention provides significant advantages over the prior art. A database may be organized in multi-linear versions and a version graph, allowing an application to access implicitly an object graph of a given version in a given branch through object fault. Further, a long transaction may be modeled using a sequence of "regular" transactions accessing a common branch of versions. Cooperative transactions may be accommodated, allowing team member to access the data from other team members while providing locks specific to a cooperative transaction which preserve the consistency of the database.
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 block diagram of an exemplary object graph;
FIG. 2 illustrates a block diagram of an exemplary version graphs;
FIG. 3 is a block diagram of a computer database system according to an embodiment of the present invention; and
FIG. 4 is a flow chart of a method of controlling consistency in a database according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The preferred embodiment of the present invention is best understood by referring to FIGS. 1-4 of the drawings, like numerals being used for like and corresponding parts of the various drawings.
Linear versions are provided for in Zeitgeist, described in U.S. patent application Ser. No. 07/531,493, filed May 30, 1990, entitled "A System and Method For Database Management Supporting Object-Oriented Programming", by Bannon et al. which is incorporated by reference herein. The linear versions present a unique way for organizing objects in a database. Briefly, a Zeitgeist user can view his database as a set of triplets <oid t, value> where oid is an object identifier, t is a timestamp, and value is the associated value of the object at the given timestamp. An update on an object always appends a new value with a more recent timestamp to the object. An application program retrieves an object either explicitly by specifying an oid and a t or implicitly through object fault when dereferencing a pointer.
In a linear version system, a pointer referencing another object contains only oid so that an object graph can be specified independent of versions. An exemplary object graph is shown schematically in FIG. 1. In this object graph 10, the object "car" 12 points to related objects "door" 14, "hood" 16, "trunk" 18 and "bumper" 20.
Further relations are shown as the object "door" 14 points to objects "handle" 22 and "lock" 24. A particular version of an object graph is uniquely identified by a timestamp, referred to as a "time context" in Zeitgeist.
Given timestamp t, the version of an object graph consists of one version from each object that has the most recent timestamp with respect to t.
Being an integral part of this object graph concept, the object faulting mechanism is designed to fetch a version of an object graph into the main memory without any apparent action on the part of a user. In the example of FIG. 1, the user would not need to explicitly fetch the object "door" 14 once the object "car" 12 had been brought into memory; instead, the object "door" 14 could be brought into memory by merely referencing "door" 14. The object faulting mechanism, however, breaks down when branching versions are stored as linear versions in a database.
There are two ways to map branching versions into linear versions. One way is to use a new oid for each object in a new branch of versions. In this approach, the representation of an object graph depends on the branch of versions the object graph is in. Code developed for one branch of versions cannot be reused directly in another branch of versions. This approach is the only method which can be used in non-linear versions.
The other approach is to map versions of different branches of an object into different linear versions of the same object. The following example illustrates this approach.
As an example, assume that a database of linear versions consists of two objects, x and y. Let x(t 1 ) denote the version of object x with timestamp t 1 . Let A and B be the names of two branches of versions. The following mapping of objects from versions in A and B to linear versions is based on the time that the objects are updated within each branch of versions. Let the versions of x and y at t=0 be x(0) and y(0). Table 1 illustrates the changing of the objects by the two branches from t=1 to t=4.
TABLE 1______________________________________t = 1 t = 2 t = 3 t = 4______________________________________A x(0) --> x(1) y(0) --> y(3)B x(0) --> x(2) y(0) --> y(4)______________________________________
TABLE 2______________________________________TIME CONTEXT VERSIONS______________________________________t = 0 {x(0), y(0)}t = 1 {x(1), y(0)}t = 2 {x(2), y(0)}t = 3 {x(2), y(3)}t> = 4 {x(2), y(4)}______________________________________
The above example is typical for mapping different branch versions of an object into different timestamps of the same object. This kind of mapping also precludes versions of two branches of an object having the same timestamps being created. The object graph is again no longer version independent. It is only by coincidence that branch B's most recent version is the same as those of time context t>=4. In general, a version of an object graph in a given branch cannot be identified with a time context. The current object faulting algorithm cannot, therefore, be used to fault in a version of an object graph in a given branch. An application program must rely on the explicit fetch command to fetch one object at a time in referencing an object graph--a tedious operation for a user to do.
The present invention may be implemented using a general purpose computer. In the present invention, a multi-linear approach is utilized. In a multi-linear version scheme, the database can be viewed as a set of 4-tuples, <oid, b, t, value>and a version graph. The new quantity b represents the name of a branch of versions. The version graph represents the relationship among the branches of versions. The other three quantities, oid, t, and value, represent the same factors as in linear versions. An object graph in this model is represented in a version independent way--a pointer to an object in the database contains only oid.
Whenever an application changes an object in a multi-linear version database, the object is never modified in place; a new version of the object is stamped (b m ,t n ), where b m is the name of a branch of versions (i.e., a branch name) and t n a unique timestamp, and appended to the branch b m in the database. When a new branch b m+1 is created from branch b m the new branch is timestamped T(b m+1 ); the parent and child relationship between branch b m and b m+1 together with their timestamps are kept in a version graph shown schematically in FIG. 2. The version graph 26 shows a parent branch 28 (with branch name "b 0 " and timestamp "t 0 ") with two child branches 30 and 32. The child branches 30 and 32 have each created new versions of the "car" object from the parent branch 28. An object in the parent branch b m is accessible in the child branch b m+1 using the concept of "copy-on-write" wherein the objects from the parent are copied only at the time when they can no longer be shared between parent and child branches. Also, a "context", c, is defined to be (B(c),S(c)) where B(c) is the branch name of c and S(c) the timestamp of c. Context is a generalization of the time context of linear versions.
The previous example is presented again using the multi-linear approach described above. Assume that a database of multi-linear versions contains two objects x and y. Let x(b,t 1 ) denote the version of object x with branch name b and timestamp t 1 . Let A and B denote the names of two branches of versions. The following represents one scenario that two applications, one using the branch of versions A and the other B, may have updated the database at time t=1,2,3, and 4. Let A and B have a common parent branch 0 at time t=0 and the versions of x and y at time t=0 be x(0,0) and y(0,0).
TABLE 3__________________________________________________________________________t = 1 t = 2 t = 3 t = 4__________________________________________________________________________A x(0, 0) --> x(A, 1) y(0, 0) --> y(A, 3)B x(0, 0) --> x(B, 2) y(0, 0) --> y(B, 4)__________________________________________________________________________
The most recent versions in branches A, B and 0 at t>4 are, respectively, {x(A,1),y(A,3)}, {x(B,2),y(B,4)} and {x(0,0),y(0,0)}. The versions that correspond to different contexts are shown in Table 4.
TABLE 4______________________________________ c(A, t) c(B, t)______________________________________t = 0 {x(0, 0),y(0, 0) {x(0, 0),y(0, 0)}t = 1 {x(A, 1),y(0, 0) {x(0, 0),y(0, 0)}t = 2 {x(A, 1),y(0, 0) {x(B, 2),y(0, 0)}t = 3 {x(A, 1),y(A,3) {x(B, 2),y(0, 0)}t> = 4 {x(A, 1),y(A,3) {x(B, 2),y(B, 4)}______________________________________
The example illustrates that the set of instances for each context is clearly identifiable; the object faulting algorithm can thus be used to fetch implicitly an object graph from database into main memory for each given context.
A storage manager supporting multi-linear versions has the following interface functions:
Fetch(c 1 ,c 2 ,oid) function fetches an object from the database. The arguments c 1 and c 2 are contexts and oid is the identifier of the fetched object; the branch B(c 1 ) is an ancestor branch of B(c 2 ) in the version graph; and the timestamp S(c 1 )←is less than or equal to the timestamp S(c 2 ). The following steps implement the idea of copy-on-write in fetching an object:
1. Let b=B(c 2 ) and t=S(c 2 ) Execute Step 2.
2. Search for an object with the given oid in branch b and which has a timestamp that is most recent with respect to t; if an object is found, return it. Otherwise execute step 3.
3. Let t=T(b) and b be the parent branch of b. If either t<=S(c 1 ) or b is a parent branch of B(c 1 ), then return "not found". Otherwise go to execute step 2 again.
Step 3 is executed when the object that has an earlier timestamp than t cannot be found in branch b; the search of the same object then begins at the parent branch of b with a timestamp earlier than the timestamp of b-the creation time of b. The adjustment of the timestamp of t is required because the object may have a version created in the parent branch of b after b has been created.
CreateObject(c) function creates a new object in the current context. A unique oid is returned.
CreateBranch(from) function creates a new branch from a given existing branch, from. A timestamped unique branch name is entered in the version graph and returned to the caller.
An application can fetch an object either using explicitly the fetch function or implicitly the object faulting mechanism. Object fault occurs when an application dereferences a pointer. Object faulting also invokes the fetch function; the arguments of fetch are a default context and the oid in the pointer being dereferenced. The invocation of the fetch function by the computer during object faulting is transparent to the user.
A version graph comprises branches as nodes and parent-child relationships as edges. Each branch is created with a unique timestamp. A node in a version graph contains a branch name and its timestamp. A direct edge from node (b 1 ,t 1 ) of branch b 1 and timestamp t 1 to node (b 2 t 2 ) of branch b 2 and timestamp t 2 means that branch b 2 is a child branch of b 1 . The fetch function uses the version graph to implement copy-on-write in fetching an object.
Given an oid, the same objects in different branches are locked separately; locking an object of one branch does not preclude the same object (i.e., with the same oid) in other branches from being accessed. A long transaction and a short transaction accessing the same object of different branches do not, therefore, block each other.
A long transaction in a multi-linear version model can be thought as a sequence of "regular" transactions operating on a private branch of a database. The intermediate results are saved in the database when a member transaction of the sequence commits. To abort a long transaction in this model simply discards the associated branch of objects. To commit a long transaction is equivalent to merging the branch with its parent branch; minor inconsistencies between versions encountered during merging can be adjusted manually.
A branch and its parent branch in a version graph can be associated with different data definitions of an object as found in schema evolution. When an object that exists in the parent branch is referenced for the first time in the child branch, a conversion from the old to the new data definition can then be triggered to take place. In other words, the proposed scheme can support directly a lazy evaluation style of schema evolution.
In a cooperative design team, members can view each other's intermediate results. The work done by an individual member cannot be atomic with respect to other members'. But the collection of work done by all members should preserve database consistency. That is, a cooperating team's work should be serializable with the work done outside the team. In short, a cooperative transaction model should satisfy:
The work done by the entire team is an atomic transaction.
Members of a cooperative design team can view and modify each other's intermediate results.
The multi-threaded transaction model disclosed herein solves the cooperative transaction problem. A thread models the work of a member of a cooperating team. Objects locked by a transaction are accessible to all the threads of the transaction; members of a team could access each other's intermediate results. A team's work that is modeled by a multi-threaded transaction preserves database consistency as a "regular" transaction does.
In a multi-threaded transaction that models the cooperative design work a thread models the work of a member of a cooperating team. The following schemes solves the concurrency control problems associated in a multi-threaded transaction.
1. Shared access among threads
Objects locked by a transaction are accessible to all the threads of a transaction. Concurrency control among threads again can be resolved through locking. The execution of the threads of a transaction clearly are not serializable. Locking at thread level does not need to follow the two-phase locking protocol. As soon as the access of an object is over, a thread should release the lock. A lock released by a thread should be retained by the transaction until the transaction commits so that a strict two-phase locking protocol is observed at the transaction level.
"ThreadRead" is a shared lock and guarantees that no other threads can append a new version to the object. This command may be used by a team member who must have the latest version of an object. "ThreadWrite" is an exclusive lock that allows the owner of the lock to append a new version to the object. A "ThreadNotification" lock is used when a thread wishes to be notified whenever there is a newer version appended to the object by other threads or transactions.
2. Transparency of thread level locks
An application writer should see no difference between thread level and transaction level locks. A thread should release a lock as soon as its use is over. The system manages the mapping between the thread level locks and the transaction levels. The system also retains the transaction level locks for a transaction until it commits (or aborts) to enforce the two-phase locking protocol at the transaction level.
3. Two-phase commit
The commit action must be synchronized among the threads using two-phase commit protocol.
4. Deadlock
A thread waiting for a lock to be released by a different thread or transaction may deadlock with the other threads or transactions. Since a thread cannot be restarted the same way as a transaction, the resolution of deadlock involving a thread should be left as a user's or a cooperating team's responsibility. Deadlock among threads of a transaction distinguishes multi-thread transaction from a distributed transaction because there is generally no deadlock among the threads at different sites of a distributed transaction if the objects at different sites are disjoint and each thread accesses the data local to its thread. If deadlock is unwanted among threads of a transaction, an application may itself use any scheme to prevent deadlock from occurring.
5. User Interface
A Begin -- Thread function with a transaction id as input argument returns a unique thread id if it is successfully registered with the transaction.
Otherwise Begin -- Thread returns a Null value. Most interface functions that are available in a transaction are also applicable in a thread of a transaction.
Representing an object graph independent of its versions is an important design feature that enables code reuse when an application needs to work with different versions. The current implementation in Zeitgeist is adequate for linear versions, but not for branching versions. Both long duration transactions and fine grain version management need to deal with branching versions at storage level. Multi-linear versions, a model for supporting branching versions, preserve the representation independence of an object graph and are a natural extension of the current implementation of linear versions in Zeitgeist.
FIG. 3 is a block diagram of a computer database system 40 comprising processing circuitry 44 and circuitry 42 for interacting with the users of the database. The processing circuitry 44 is operable to represent each version of an element 54 of the database with unique identifier 46, timestamp 50, branch name 48 and value 52. Processing circuitry 44 is operable to create a new version of an element 54 in response to an operation which would modify the element 54 and to modify the value of the new version of the element 54 responsive to said operation.
FIG. 4 is a flow chart of a method of controlling consistency is a database illustrating the steps of representing each version of an element of the database with a unique identifier, a timestamp, a branch name and a value (block 52) and creating a new version of an element in response to an operation which would modify the element (block 54). Thereafter, the value of the new version of the element is modified responsive to the operation (block 56).
The present invention provides several technical advantages over the prior art. A database may be organized in multi-linear versions and a version graph so that an application can access implicitly an object graph of a given version in a given branch through object fault.
Further, a long transaction may be modeled using a sequence of "regular" transactions accessing a common branch of versions.
The present invention supports fine grain version management at the storage management level. The version graph is for the entire database-not one version graph per object. Also, the present invention supports lazy evaluation style schema evolution directly.
While the present invention has been described in connection with an object oriented database, it may be used in connection with other databases as well.
Although the present invention has 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. | Each element of a database may have multiple versions; the versions are partitioned into branches, and versions of a branch are ordered linearly according to their timestamps. Branches are timestamped and related to one another by a version graph. Each version of an element of a database is represented by a unique identifier, a timestamp, a branch name and a value. A new version of an element associated with a branch is created in response to an operation associated with the branch which would modify the element. An object graph in the database is represented independent of the branches and version; an application coded for elements in one version (and branch) can be reused for the same elements in a different version and (different branch) without any re-coding effort. Methods for long duration transactions, cooperative transactions and schema evolutions are provided. | 8 |
BACKGROUND OF THE INVENTION
[0001] This application relates to a refrigerant system utilizing tandem compressors sharing a common condenser, but having separate evaporators, and wherein an economizer circuit and a reheat coil are incorporated.
[0002] Refrigerant systems are utilized in applications to change the temperature and humidity or otherwise condition the environment. In a standard refrigerant system, a compressor delivers a compressed refrigerant to an outdoor heat exchanger, known as a condenser. From the condenser, the refrigerant passes through an expansion device, and then to an indoor heat exchanger, known as an evaporator. In the evaporator, moisture may be removed from the air, and the temperature of air blown over the evaporator coil is lowered. From the evaporator, the refrigerant returns to the compressor. Of course, basic refrigerant systems are utilized in combination with many configuration variations and optional features. However, the above provides a brief understanding of the fundamental concept.
[0003] In more advanced refrigerant systems, a capacity of the air conditioning system can be controlled by the employment of so-called tandem compressors. The tandem compressors are normally connected together via common suction and common discharge manifolds. From a single common evaporator, the refrigerant returns through the common suction manifold to each of the tandem compressors. From the individual compressors the refrigerant is delivered into the common discharge manifold and then into a single common condenser. The tandem compressors are also separately controlled and can be started and shut off independently of each other such that one or both compressors may be running at a time. By controlling which compressors are operating, control over the capacity of the entire system is achieved. Often, the two compressors are selected to have different capacities, such that even greater flexibility in capacity control is provided. Also, tandem compressors may have shutoff valves to isolate some of the compressors from the active refrigerant circuit, when they are shutdown. Moreover, if these compressors operate at different suction pressures, then pressure equalization and oil equalization lines are frequently employed.
[0004] One advantage of the tandem compressor is that more capacity control is provided, without the requirement of having each of the compressors operating on a dedicated circuit. This reduces the system cost.
[0005] However, certain applications require cooling at various temperature levels. For example, in supermarkets, low temperature (refrigeration) cooling can be provided to a refrigeration case by one of the evaporators connected to one compressor and intermediate temperature (perishable) cooling can be supplied by another evaporator connected to another compressor. In another example, a computer room and a conventional room would also require cooling loads provided at different temperature levels, which can be achieved by the proposed multi-temp system as desired. However the cooling at different levels will not work with an application of a standard tandem compressor configuration, as it would require the application of a dedicated circuit for each cooling level. Each circuit in turn must be equipped with a dedicated compressor, dedicated evaporator, dedicated condenser, dedicated expansion device and dedicated evaporator and condenser fans. This arrangement having a dedicated circuitry for each temperature level would be extremely expensive.
[0006] In addition, a technique known as an economizer circuit has been utilized in refrigerant systems. The economizer circuit increases the capacity and efficiency of a refrigerant system. To this point, a system having a common condenser communicating with several evaporators has not been utilized in combination with any economizer circuit. Notably, applicants have a co-pending application, filed on even date herewith, entitled “Refrigerant Cycle With Tandem Compressors for Multi-Level Cooling, and assigned Ser. No. ______.
[0007] In some cases, while the system is operating in a cooling mode, the temperature level at which the air is delivered to provide comfort environment in a conditioned space may need to be higher than the temperature that would provide the ideal humidity level. Generally, the lower the temperature of the evaporator coil is the more moisture can be removed from the air stream. These opposite trends have presented challenges to refrigerant system designers. One way to address such challenges is to utilize various schematics incorporating reheat coils. In many cases, a reheat coil placed in the way of an indoor air stream behind the evaporator is employed for the purposes of reheating the air supplied to the conditioned space after it has been cooled in the evaporator, where the moisture has been removed as well.
[0008] While reheat coils have been incorporated into air conditioning systems, they have not been utilized in an air conditioning system having an ability to operate at multiple temperature levels by employing tandem compressors, with at least one of the tandem compressors operating in conjunction with the economizer circuit.
SUMMARY OF THE INVENTION
[0009] For the simplest system that has only two compressors, in this invention, as opposed to the conventional tandem compressor system, there is no common suction manifold connecting the tandem compressors together. Each of the tandem compressors is connected to its own evaporator; while, both compressors are still connected to a common discharge manifold and a single common condenser. Consequently, for such tandem compressor system configurations, additional temperature levels of cooling, associated with each evaporator, become available. An amount of refrigerant flowing through each evaporator can be regulated by flow control devices placed at the compressor suction ports, as well as by controlling related expansion devices or utilizing other control means, such as evaporator airflow. In addition, in this application, an economizer circuit is incorporated into the refrigerant system. The economizer circuit maybe utilized with one or several of the evaporators. In particular, the economizer circuit may increase the capacity of each evaporator, and thus it would preferably be utilized (to obtain the most benefits) with the evaporator associated with the environment that must be controlled at the lowest temperature.
[0010] In addition, a single or multiple reheat coils are associated with one or several evaporators. The reheat coils may be positioned in a parallel or serial flow relationship with an economizer heat exchanger and condenser and can be located either upstream or downstream of each heat exchanger.
[0011] In embodiments, only one or several of the evaporators may be associated with the economizer circuit. In the economizer circuit, a portion of the refrigerant is then returned to an intermediate compression position in at least one of the compressors and can be tapped from the main circuit either upstream or downstream of the economizer heat exchanger, as known. Also, the teachings of this invention can be equally applied to compressors connected in series or economized compressors having multiple injection ports.
[0012] 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
[0013] FIG. 1 shows an earlier system.
[0014] FIG. 2 is a first schematic.
[0015] FIG. 3A is a second schematic.
[0016] FIG. 3B shows another option.
[0017] FIG. 4 is a third schematic.
[0018] FIG. 5 is a fourth schematic.
[0019] FIG. 6 illustrates another option.
[0020] FIG. 7 illustrates yet another option.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0021] Referring to FIG. 1 , earlier tandem compressor system 10 is shown to include two separate compressors 11 , a common evaporator 17 , condenser 15 , expansion device 14 , condenser air-moving device 16 , evaporator air-moving device 18 and associated piping. An economizer circuit has an economizer heat exchanger 15 receiving a main refrigerant flow and a tapped refrigerant flow in line 7 . As known, the tapped refrigerant flow passes through an expansion device 9 to be expanded to lower pressure and temperature. Downstream of the economizer heat exchanger 15 , the tapped flow is returned through a line 8 to an intermediate point in at least one of the compressors 11 . Such a system was disclosed in a prior U.S. patent application Ser. No. 10/769,161, filed 30 Jan. 2004, entitled “Refrigerant Cycle With Tandem Economized and Conventional Compressors” and assigned to the assignee of the present invention. As known, the tap line 7 may also be located downstream of the economizer heat exchanger 15 .
[0022] A refrigerant system 20 is illustrated in FIG. 2 having a pair of compressors 22 and 23 that are operating generally as tandem compressors. Optional discharge valves 26 are positioned downstream of these compressors on discharge lines associated with each of the compressors 22 and 23 . These valves can be controlled to prevent backflow of refrigerant to either of the compressors 22 or 23 should only one of the compressors be operational. That is, if for instance the compressor 22 is operational with the compressor 23 stopped, then the discharge valve 26 associated with compressor 23 will be closed to prevent flow of refrigerant from the compressor 22 back to the compressor 23 . The two compressors communicate with a discharge manifold 29 leading to a common condenser 28 . From the condenser 28 , the refrigerant continues downstream and is split into two flows, each heading through an expansion device 30 . From the expansion device 30 , one of the flows passes through a first evaporator 32 for conditioning a sub-environment B. The refrigerant passing through the evaporator 32 passes then through a suction modulation valve 34 , and is returned to the compressor 22 . The second refrigerant flow passes through an evaporator 36 that is conditioning a sub-environment A. The refrigerant also passes through an optional suction modulation valve 34 downstream of the evaporator 36 and is returned to the compressor 23 . An air-moving device F drives air over the evaporator 32 and another air-moving device F drives air over the evaporator 36 and into their respective sub-environments. Usually, sub-environments A and B are preferably maintained at different temperature levels.
[0023] A control 40 for the refrigerant system 20 is operably connected to control the compressors 22 and 23 , the expansion devices 30 , the discharge valves 26 , and suction modulation valves 34 . By properly controlling each of these components in combination, the conditions at each evaporator 32 and 36 can be controlled as necessary for the sub-environments A and B. The exact controls necessary are as known in the art, and will not be explained here. However, the use of the tandem compressors 22 and 23 utilizing the common condenser 28 and separate evaporators 32 and 36 , preferably operating at different temperature levels, reduces the number of components necessary for providing the independent control for the sub-environments A and B, and thus is an improvement over the prior art.
[0024] As shown in FIG. 2 , an economizer circuit 100 is incorporated into the refrigerant system 20 . An economizer heat exchanger 102 receives a refrigerant from an economizer tap 104 and a main refrigerant flow line 106 . Notably, the refrigerant heading to the evaporator 32 does not pass through the economizer heat exchanger 102 , while the refrigerant heading to the evaporator 36 does. In this embodiment, the evaporator 36 and its sub-environment A is preferably the environment that must be maintained at a lower temperature. The use of the economizer circuit will provide additional cooling capacity for the evaporator 36 , as known. The refrigerant passing through the tap 104 passes through an expansion device 108 to be expanded to lower pressure and temperature. This refrigerant thus subcools the refrigerant in the main flow line 106 in the economizer heat exchanger 102 . The tapped refrigerant, having been expanded and passed through the economizer heat exchanger 102 , returns through a return line 110 to an intermediate compression point in at least one of the compressors, shown here as compressor 23 . Notably, while the flow in the lines 104 and 106 are shown in the same direction through the economizer heat exchanger 102 , for all of the embodiments in this invention, it is preferred that these two flows are arranged in a counter-flow relationship, however, they are shown in the same direction for illustration simplicity.
[0025] The use of the economizer circuit 100 provides additional cooling capacity to the refrigerant system 20 .
[0026] For this embodiment, and for all other disclosed embodiments, there is an option where the control can also selectively open the economizer expansion device to either allow flow through the economizer heat exchanger, or to block flow through the economizer heat exchanger. When the economizer expansion device is shut off, refrigerant would still pass through the economizer heat exchanger through the main flow line, however, the economizer function would not be operational. Rather than having a single economizer expansion device that also operates as a shut-off valve, two distinct flow control devices could be utilized. Also, as mentioned above, the tap refrigerant line 104 may be located downstream of the economizer heat exchanger 102 , providing similar benefits.
[0027] In addition, a reheat circuit is incorporated into the system 20 . In particular, the reheat circuit includes a flow control device 116 for selectively tapping a refrigerant through a reheat coil 118 associated with the sub-environment A. When the control 40 determines that a reheat function is desired, the valve 116 will be opened and refrigerant will pass through the reheat coil 118 , through a check valve 120 , and be returned at point 122 to the main refrigerant circuit, upstream of one of the expansion devices 30 . At least a portion of air driven by the air-moving device F over the evaporator 36 will also now pass over the reheat coil 118 . As is known, this air can be cooled in the evaporator 36 , and in particular cooled to a lower temperature by employment of the economizer circuit 100 , such that greater dehumidification can be achieved. If the temperature of the air having passed over the evaporator 36 is lower than would be desired in the sub-environment A, then the reheat coil 118 is utilized to heat the air to a desired temperature level after the moisture has been removed in the evaporator 36 .
[0028] Obviously, the economizer heat exchanger 102 and reheat coil 118 can be associated with different evaporators 32 and 36 if desired. Furthermore, although a warm liquid approach (with the reheat coil 118 located downstream of the condenser 28 and arranged in a parallel relationship with the economizer heat exchanger 102 ) is shown in FIG. 1 , any reheat concept (e.g. hot gas, warm liquid, two-phase mixture) as well as reheat circuit configuration and relative position can be employed, providing similar system advantages in flexibility and control of satisfying a wide spectrum of potential applications and various external sensible and latent load demands. Thus, in systems employing such reheat concepts, the position of the reheat coil in the refrigerant circuit in relation to the condenser 28 and economizer heat exchanger 102 may be sequential or parallel as well as upstream or downstream.
[0029] As shown in FIG. 2 , a bypass line 315 may bypass refrigerant around the condenser 28 when a flow control device such as valve 316 is opened. This bypass may be selectively utilized by the control 40 when dehumidification is desired with a lower sensible cooling load. Such bypasses are known in the art, and a worker of ordinary skill in this art would recognize how to incorporate this feature into the schematic 20 , and when to utilize the feature.
[0030] FIG. 3A shows another embodiment 50 that is quite similar to the embodiment 20 of FIG. 2 . However, the refrigerant flowing to both of the evaporators 32 and 36 passes through the economizer heat exchanger 102 . As shown, the main flow of refrigerant 106 leads to a downstream manifold 116 , which then breaks into branches leading to both evaporators 32 and 36 . The benefits of additional capacity are thus provided to both of the evaporators. As shown, the refrigerant being returned to the compressor 22 would still return through the line 110 . An optional line 114 may also return refrigerant to the other compressor 23 , if this compressor is equipped with intermediate injection port as well.
[0031] Reheat coils are also incorporated into the refrigerant cycle 50 . Here, a first three-way valve 52 is positioned downstream of the economizer heat exchanger 102 , and directs refrigerant through a first reheat coil 54 associated with the evaporator 36 and sub-environment A when a reheat function desired. Refrigerant flowing through the reheat coil 54 then passes through a check valve 56 , and is returned at point 58 to the main circuit refrigerant line, upstream of the expansion device 30 . In this case, a warm liquid approach is utilized once again, but now with the reheat coil 54 located downstream of both condenser 28 and economizer heat exchanger 102 . A second three-way valve 60 selectively taps refrigerant off of a main refrigerant line, and passes it through a second reheat coil 62 associated with the sub-environment B. Refrigerant flowing through the reheat coil 62 then passes through a check valve 64 and is reconnected at point 66 to the main refrigerant line. Here, a hot gas design is employed with the reheat coil 62 positioned upstream of the condenser 28 . The control 40 will selectively operate each of the reheat coils dependent on the desired humidification and temperature needs of the sub-environments A and B. As shown in FIG. 3B , both reheat coils 54 and 62 can be associated with a single evaporator ( 32 or 36 ) and consequently with a respective sub-environment (B or A), providing multiple reheat stages for this sub-environment. Although the reheat coils 54 and 62 are shown in series (one behind the other) relative to the air path, a parallel configuration is also feasible.
[0032] FIG. 4 shows a refrigerant cycle 80 , wherein, once again, there are reheat coils associated with each of the two sub-environments A and B. However, in this embodiment, a single three-way valve 82 is positioned downstream of the main flow line passing through the economizer heat exchanger 102 . Refrigerant having been tapped from the three-way valve 82 passes to a connection 94 , through two lines 86 , and selectively operable flow control devices 84 , can pass to the two reheat coils 88 and 90 . These two refrigerant flows recombine at a point 89 , pass through a check valve 92 , and are reconnected at the point 94 upstream of the expansion device 30 . Thus, in this relationship, the two reheat coils 88 and 90 are in generally parallel configuration such that the refrigerant conditions at the entrance to the reheat coils is generally the same. The control 40 will selectively operate both flow control devices 84 associated with the reheat coils 88 and 90 to be either open or closed to provide refrigerant flow to each of reheat coils associated with sub-environment B and A respectively when the reheat function is desired in each sub-environment. Obviously, the flow control devices can be of an adjustable type to control amount of refrigerant to each reheat coil through modulation or pulsation. As it would be recognized by a worker ordinarily skilled in the art, other parallel configurations of the reheat coils are also feasible.
[0033] FIG. 5 shows an embodiment 190 where the two reheat coils are in a serial flow relationship. A three-way valve 192 taps refrigerant through a first reheat coil 194 associated with the sub-environment B, and the refrigerant then passes downstream serially to a reheat coil 196 associated with the sub-environment A. The refrigerant then passes through a check valve 198 , and is reconnected at a point 200 to the main refrigerant flow. As can be appreciated, the refrigerant will have a higher temperature at the reheat coil 196 than it would at the reheat coil 194 , and thus the selection of which sub-environment A and B should first receive the refrigerant flow should be made based upon which sub-environment requires a higher amount of reheat. As it would be recognized by a worker ordinarily skilled in the art, other serial arrangements of the reheat coils are also feasible.
[0034] FIG. 6 shows yet another schematic 200 , wherein there are serially connected compressors 202 and 204 (instead of a single economized compressor). A discharge line 206 downstream of the second stage compressor 204 delivers refrigerant to a condenser 208 . A refrigerant line 210 downstream of the first stage compressor 202 accepts refrigerant from the economizer heat exchanger at an intermediate pressure level. Obviously, any economized compressor can be substituted by a serially connected compressor stages and more than two sequential compressor stages can be employed as well if desired.
[0035] FIG. 7 shows an embodiment 250 , having an economized compressor 252 , such as mentioned above, wherein there are plural intermediate taps 254 and 256 , each connected to a respective economizer heat exchanger operating at a different pressure and temperature level and thus providing different amount of subcooling. Such economizer heat exchangers can be arranged in a sequential or parallel configuration to each other. Of course, more than two taps are feasible.
[0036] In all of the disclosed embodiments, the economizer circuit and reheat coils assist in providing the distinct temperatures and humidity levels that are to be achieved by one or several of the evaporators. That is, by providing the economizer circuit and reheat coil, the present invention is better able to meet the temperature and dehumidification goals for a wide spectrum of potential applications as well as sensible and latent load demands.
[0037] Other multiples of compressors and compressor banks can be utilized.
[0038] Although preferred embodiments of this invention have 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. | A tandem compressor refrigerant system where an economizer circuit and reheat coil are incorporated to provide additional flexibility and control over overall system capacity and sensible heat ratio as well as to increase system efficiency. In this system, tandem compressors deliver compressed refrigerant to a common discharge manifold, and then to a common condenser. From the common condenser, the refrigerant passes to a plurality of evaporators, with each of the evaporators being associated with a separate environment to be conditioned. Each of the evaporators is associated with one or several of the plurality of compressors. By utilizing the common condenser, yet a plurality of evaporators, the ability to independently condition a number of sub-environments is achieved without the requirement of the same plurality of complete separate refrigerant circuits for each compressor. In particular, the economizer circuit provides additional capacity to any of the evaporators that have a relatively high load while the reheat coil provides improved dehumidification. Various design schematics and system configurations are disclosed. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates a foldable mobile terminal device in which an upper casing and a lower casing are rotatably coupled.
2. Description of the Related Art
In recent years, the mobile phone is equipped with a camera function for photographing subjects, a browser function for browsing web sites, a television function for viewing television programs and so on, in addition to a standard talking function, a transmission/reception function for electronic mails, etc. The mobile phone has been used not only as means for performing communications, but also has been used, among people of all ages, as one's own multifunctional terminal that substitutes for a digital camera, personal computer, and television.
However, although usual televisions or personal computers have a display screen with a horizontally elongated shape, mobile phone terminals typically have a vertically elongated shape on a whole, and the display screen thereof has also a vertically elongated shape in order to improve holdability or operability by one hand. As a consequence, when a horizontally elongated shaped image displayed on a television or personal computer is browsed by the mobile telephone, the image is often displayed by reducing its size in keeping with the display screen of a vertically elongated shape, or the image is often displayed sideways with respect to the display screen and a user browses the image by holding sideways the mobile phone. This raises a problem that either of the size of an image and the holdability of the mobile phone becomes victim to the other.
Japanese Unexamined Patent Application Publication No. 2003-319043 discloses a foldable mobile phone including an upper casing having a display screen, a lower casing having an operator, and a support casing that is hingedly connected to the lower casing and that supports the upper casing so as to be able to rotate the upper casing in the left/right direction about a shaft.
However, as shown in FIG. 2 in the above-described patent document, in order to prevent corners of the upper casing from suffering interference from the hinge when the upper casing is rotated about the shaft provided to the support casing, the lower edge of the upper casing must be significantly curved from its center toward the left and right edge of the upper casing 100 A. As a result, in the foldable mobile phone set forth in this patent document, there occurs a problem that the display screen is reduced in size or the design of the device is limited.
SUMMARY
A mobile terminal device comprises a lower casing, an upper casing, and an intermediate casing. The intermediate casing is connected to the lower casing by a hinge structure which enables the intermediate casing to rotate about an axis. The intermediate casing supports a back surface of the upper casing by a front surface of the intermediate casing. A first casing which is either the upper casing or the intermediate casing has a first groove formed in a vertical direction with respect to the rotation axis on a surface facing a second casing which is the other of the upper casing and the intermediate casing, the second casing has a first portion protruding from a surface facing the first casing and fitting the groove of the first casing, and the upper casing is rotatable with respect to the intermediate casing for the portion being guided by the groove.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram showing an external appearance of a mobile phone according to an embodiment of the present invention;
FIG. 2 is an internal block diagram of the mobile phone according to an embodiment of the present invention;
FIG. 3 is a diagram showing the surface sides of a lower casing and an intermediate casing, with an upper casing removed according to an embodiment of the present invention;
FIG. 4 is a diagram showing the back surface side of the upper casing according to an embodiment of the present invention;
FIG. 5 is a perspective diagram of the upper casing, the lower casing, and the intermediate casing according to an embodiment of the present invention;
FIG. 6 is a diagram showing operations for inclining the upper casing toward the lower casing according to an embodiment of the present invention;
FIG. 7 is a diagram showing operations for inclining the upper casing toward the lower casing, in a mobile phone according to a second embodiment of the present invention;
FIGS. 8A and 8B , respectively, are a front view and side view of the upper casing and the intermediate casing in a mobile phone according to a third embodiment of the present invention;
FIG. 9 is an oblique perspective view of the upper casing and the intermediate casing according to a third embodiment of the present invention;
FIGS. 10A and 10B are perspective diagrams each showing a mobile phone according to a fourth embodiment of the present invention;
FIGS. 11A to 11C are enlarged diagrams each showing the vicinity of buttons in the mobile phone according to a fourth embodiment of the present invention;
FIGS. 12A and 12B are diagrams each showing an operation when one of the buttons is pushed;
FIGS. 13A and 13B are diagrams each showing a rotational operation of the upper casing;
FIGS. 14A and 14B are diagrams each showing an operation when the one of the buttons is pushed;
FIGS. 15A and 15B are diagrams each showing the upper casing in a mobile phone according to a fifth embodiment of the present invention;
FIG. 16 is a diagram showing the intermediate casing in the mobile phone;
FIG. 17 is a diagram showing operations for inclining the upper casing toward the lower casing;
FIG. 18 is a diagram showing the surface side of the intermediate casing in a mobile phone according to a sixth embodiment of the present invention;
FIG. 19 a diagram showing the back surface side of the upper casing;
FIG. 20 is a perspective diagram showing the upper casing, the lower casing, and the intermediate casing;
FIGS. 21A and 21B are diagrams showing various dimensions in the mobile phone;
FIG. 22 is a diagram showing operations for inclining the upper casing toward the lower casing;
FIGS. 23A and 23B are diagrams showing various dimensions in a mobile phone according to a seventh embodiment of the present invention;
FIG. 24 is a diagram showing operations for inclining the upper casing toward the lower casing;
FIGS. 25A and 25B are diagrams showing various dimensions in a mobile phone according to an eighth embodiment of the present invention;
FIG. 26 is a diagram showing the surface side of the intermediate casing in a mobile phone according to a ninth embodiment of the present invention;
FIG. 27 is a diagram showing the back surface side of the upper casing; and
FIG. 28 is a diagram showing operations for inclining the upper casing toward the lower casing.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hereinafter, embodiments of the present invention will be described with reference to the appended drawings.
FIG. 1 is a diagram showing an external appearance of a mobile phone to which an embodiment of the present invention has been applied;
The mobile phone shown in FIG. 1 is equipped with a photographing function for photographing subjects, a television function for viewing television programs, etc., in addition to data communications function for exchanging voices and electronic mails with an external device.
The mobile phone includes an upper casing 100 A with a liquid crystal panel 101 , a lower casing 100 B held in a hand by a user, and an intermediate casing 100 C hingedly connected to the lower casing 100 B. The upper casing 100 A is supported by the intermediate casing 100 C so as to be turnable in the right and left directions, and the upper casing 100 A and the intermediate casing 100 C are integrally opened/closed with respect to the lower casing 100 B. The upper casing 100 A is one example of what the present invention terms “upper casing”, and the lower casing 100 B is one example of what the present invention terms “lower casing”, and the intermediate casing 100 C is one example of what the present invention terms “intermediate casing”. The construction of each of these upper casing 10 A, lower casing 100 B, and intermediate casing 100 C is described in detail later.
The upper casing 100 A includes the liquid crystal panel 101 on which telephone numbers, television programs, photographed images and the like are displayed, a speaker (refer to FIG. 2 ) provided inside, and a mouthpiece 102 for uttering voices issued from a speaker. The lower casing 100 B includes a selection button 104 used for the selection of various functions and used as a shutter button in photographing, push buttons 105 for inputting telephone numbers and so on, a microphone (refer to FIG. 2 ) provided inside, and an ear piece 106 for transmitting the voices to the microphone.
Next, the internal structure of the mobile phone will be described.
FIG. 2 is an internal block diagram of the mobile phone.
FIG. 2 shows a CPU 110 , ROM 111 , nonvolatile memory 112 , RAM 113 , microphone device 121 , display device 122 , speaker device 123 , key device 124 , camera device 125 , clock 126 , short-distance device 131 , long-distance device 132 , television device 133 , media controller 140 , and rechargeable battery 150 . These are connected to one another via busses.
The CPU 110 has a function of executing various programs, and exerts control over the entire mobile phone.
The ROM 111 stores various programs to be executed by the CPU 110 , and various constants necessary for executing these various programs. The CPU 110 executes the programs stored in the ROM 111 using the RAM 113 as a work area.
The nonvolatile memory 112 records various pieces of information, such as an address book or received electronic mails, to be possibly rewritten.
The microphone device 121 is a functional block comprising a microphone for picking up voices of the user, and the processing of the voices picked up by the microphone.
The speaker device 123 is a functional block comprising a speaker for outputting voices to the user, and the producing of vocal signals for driving the speaker.
The camera device 125 is a block governing the collection of image data by photographing, the display device 122 is a block governing the display of images on the liquid crystal panel 101 (refer to FIG. 1 ), the key device 124 is a block for detecting various key-operations by the user, and the clock 126 is a block for acquiring a current time.
The media controller 140 is a block for reading data from a loaded recording media 141 or writing image data and the like produced by the camera device 125 into the recording media 141 .
The short-distance device 131 is a block for transmitting images, telephone numbers and the like to an external device at a short distance, by infrared communications without interposition of a base station (not shown).
The long-distance device 132 is a block for performing talking or the exchange of electronic mails via a base station (not shown).
The television device 133 is a block for converting electronic waves received by an antenna into digital program data by a tuner, and causing the liquid crystal panel 101 (refer to FIG. 1 ) to display programs expressed by the program data.
The mobile phone according to the present embodiment has basically the above-described constructions.
Next, the upper casing 100 A, lower casing 100 B, and intermediate casing 100 C will be each explained in a more detailed manner. Hereinafter, in a state where the upper casing 100 A and intermediate casing 100 C are opened with respect to the lower casing 100 B, the side on which the liquid crystal panel 101 is provided is referred to as the “surface” side, and the back of the side on which the liquid crystal panel 101 is provided is referred to as the “back” side.
FIG. 3 is a diagram showing the surface side of each of the lower casing 100 B and the intermediate casing 100 C, with the upper casing 100 A removed, and FIG. 4 is a diagram showing the back surface side of the upper casing 100 A.
As shown in FIG. 3 , the lower casing 100 B and the intermediate casing 100 C are connected so as to be foldable in the hinge portion 200 . The hinge portion 200 has an abutting mount 201 against which the upper casing 100 A is abutted. On the surface side of the intermediate casing 100 C, there is provided a longitudinal groove 210 extending in the vertical direction. The hinge portion 200 is one example of what the present invention terms “hinge portion”. The longitudinal groove 210 is one example of what the present invention terms “vertical groove”. The abutting mount 201 is one example of what the present invention terms “guide”, as well as one example of what the present invention terms “pillow”. In this embodiment example, the intermediate casing 100 C is one example of what the present invention terms “first casing”.
As shown in FIG. 4 , on the back surface side of the upper casing 100 A, there is provided a hollow protrusion 310 having therein a through-hole 311 . The protrusion 310 is one example of what the present invention terms “protrusion”. In this embodiment example, the upper casing 100 A is one example of what the present invention terms “second casing”.
Fitting the protrusion 310 ( FIG. 4 ) of the upper casing 100 A into the longitudinal groove 210 ( FIG. 3 ) of the intermediate casing 100 C allows the upper casing 100 A to be turnably supported by the intermediate casing 100 C.
FIG. 5 is a perspective diagram of the mobile phone.
As shown in FIG. 5 , the protrusion 310 of the upper casing 100 A has gotten into the longitudinal groove 210 of the intermediate casing 100 C. An electrical cable 410 for electrically connecting the upper casing 100 A and the lower casing 100 B is arranged through the through-hole 311 in the protrusion 310 . The electrical cable 410 is one example of what the present invention terms “electrical cable”.
The CPU 110 shown in FIG. 2 is disposed in the lower casing 100 B, while the speaker device 123 , the camera device 125 , the display device 122 and the like are disposed in the upper casing 10 A. Therefore, the upper casing 100 A and the lower casing 100 B must be electrically connected in order to exchange instructions and various pieces of data between the CPU 110 and various components. In the mobile phone according to this embodiment, passing the electrical cable 410 through the through-hole 311 in the protrusion 310 prevents the complication of wiring. This allows the electrical cable to be short, and to be inhibited from the breaking.
This mobile phone also has a spring 420 for resiliently urging downward the upper casing 100 A toward the lower casing 100 B. The spring 420 is one example of what the present invention terms “resiliently-urging member”.
FIG. 6 is a diagram showing operations for inclining the upper casing toward the lower casing.
In FIG. 6 , the electrical cable 410 and the spring 420 and the like shown in FIG. 5 are omitted from illustration in order to make the figure easily viewable.
In the upright state, in which the upper casing 100 A is not inclined toward the lower casing 100 B (step S 11 in FIG. 6 ), the spring 420 shown in FIG. 5 resiliently urges downward the upper casing 100 A toward the lower casing 100 B, and the upper casing 100 A is maintained in a longitudinal posture with respect to the lower casing 100 B. Also, the lower side of the upper casing 100 A is abutted against the abutting mount 201 to thereby reduce wobbling of the upper casing 100 A.
In this embodiment, in the upright state shown in step S 11 in FIG. 6 , it is designed that the width of the upper casing 100 A and that of the intermediate casing 100 C conform to each other and that the protrusion 310 is located at the lowest position of the longitudinal groove 210 .
When the upper casing 100 A is inclined toward the left side, the protrusion 310 moves upward under the guidance of the longitudinal groove 210 to thereby rotate the upper casing 100 A (step S 12 in FIG. 6 ). At first, by the spring 420 shown in FIG. 5 , the upper casing 100 A is resiliently urged toward the direction in which it is maintained in the upright state (step S 11 in FIG. 6 ). However, when the upper casing 100 A is further inclined against the resiliently urging force, the upper casing 100 A is resiliently urged toward the same direction as the rotational direction from the time when the upper casing 100 A is inclined by an angle of about 45 degrees. As a result, the bottom left corner of the upper casing 100 A is guided by the abutting mount 201 , as well as the protrusion 310 moves downward under the guidance of the longitudinal groove 210 , whereby the upper casing 100 A rotates (step S 12 in FIG. 6 ), and is felled sidelong toward the left side with respect to the lower casing 100 B (step S 13 in FIG. 6 ).
In the leftward felled-sidelong state shown in step S 13 , the face 1001 of the upper casing 100 A, opposite to the lower casing 100 B is abutted against the abutting mount 201 , and further the upper casing 100 A is resiliently urged downward by the spring 420 so as to maintain its leftward felled-sidelong state, thereby reducing wobbling in the leftward felled-sidelong state. Also, in the leftward felled-sidelong state, the right edge 1002 of the upper casing 100 A is flush with the right edge of the intermediate casing 100 C, and further the upper edge 1003 of the upper casing 100 A is flush with the upper edge of the intermediate casing 100 C.
Next, when the user rotates the upper casing 100 A in the right direction from the leftward felled-sidelong state (step S 13 in FIG. 6 ), the upper casing 10 A, at first, is resiliently urged by the spring 420 shown in FIG. 5 in the direction in which the upper casing 100 A is maintained in the leftward felled-sidelong state. However, as the upper casing 100 A gets close to the upright state, it is resiliently urged in the same direction as the rotational direction. As a result, the upper casing 100 A rotates while being guided by the abutting mount 201 , and thus returns to the upright state.
On the other hand, when the user inclines the upper casing 100 A from the upright state (step S 11 in FIG. 6 ) in the right direction (step S 14 in FIG. 6 ), the protrusion 310 of the upper casing 100 A is guided by the longitudinal groove 210 , as well as the bottom right corner of the upper casing 100 A is guided by the abutting mount 201 , whereby the upper casing 100 A is felled sidelong toward the right side with respect to the lower casing 100 B (step S 15 in FIG. 6 ).
As described above, according to the mobile phone of the present invention, it is possible to easily incline the upper casing 100 A leftward and rightward with respect to lower casing 100 B, without providing a large curve to each of the lower corners of the upper casing 100 A. This allows the upper casing 100 A to have a large liquid crystal panel 101 , which makes it possible to browse an image by displaying it in a large size while maintaining the holdability of the mobile phone.
Next, a second embodiment according to the present invention will be described. Because the second embodiment has the same construction as that of the first embodiment except that a longitudinal groove 210 in the intermediate casing 100 C in the second embodiment is different in length from that in the first embodiment. Therefore, in this embodiment, the same components as those in the first embodiment are designated by the same symbols, and description thereof is omitted. Only differences of the second embodiment from the first embodiment are described.
FIG. 7 is a diagram showing operations for inclining the upper casing toward the lower casing, in a mobile phone according to the present embodiment.
The mobile phone according to this embodiment has substantially the same construction as that according to the first embodiment shown in FIG. 6 , but a longitudinal groove 210 ′ is longer than the longitudinal groove 210 in the first embodiment, and the protrusion 310 is designed to come to an intermediate position of the longitudinal groove 210 ′ in the upright state shown in step S 21 in FIG. 7 .
When the upper casing 100 A is inclined toward the left side (step S 22 in FIG. 7 ), as in the case of the first embodiment, the upper casing 100 A is resiliently urged downward by the spring 420 shown in FIG. 5 , the protrusion 310 is guided by the longitudinal groove 210 ′ and the bottom left corner of the upper casing 100 A is guided by the abutting mount 201 and the like.
In the leftward felled-sidelong state in which the upper casing 100 A has been felled sidelong toward the left side with respect to the lower casing 100 B (step S 23 in FIG. 7 ), the right edge 1004 of the upper casing 100 A does not become flush with the right edge 1005 of the intermediate casing 100 C, and the entire upper casing 100 A is brought close to the center, differently from the leftward felled-sidelong state in the first embodiment (step S 13 in FIG. 6 ).
Also, when the upper casing 100 A is inclined (step S 24 in FIG. 7 ) and has been completely felled sidelong toward the right side with respect to the lower casing 100 B (step S 25 in FIG. 7 ), the left edge 1006 of the upper casing 100 A does not become flush with the left edge 1007 of the intermediate casing 100 C, and the upper casing 100 A is brought close to the center.
In this manner, bringing the entire upper casing 100 A close to the center when the upper casing 100 A is inclined into leftward felled-sidelong state and rightward felled-sidelong state, allows an improvement in a feeling of stability when the mobile phone is held in a hand.
A third embodiment according to the present invention will now be described. Because the third embodiment has the same construction as that of the first embodiment except that the shape of a hinge portion 200 in the third embodiment is different from that in the first embodiment, only differences of the third embodiment from the first embodiment are described.
FIGS. 8A and 8B , respectively, are a front view and a side view of the upper casing 100 A and the intermediate casing 100 C in the mobile phone according to this embodiment, and FIG. 9 is an oblique perspective view of the upper casing 100 A and the intermediate casing 100 C in the mobile phone according to this embodiment.
As shown in FIGS. 8A and 8B , in this embodiment, a dent portion 520 is provided at each of the left and right ends of the hinge portion 200 in the intermediate casing 100 C. The dent portion is one example of what the present invention call “recess portion”.
As shown in FIG. 9 , the dent portion 520 is a spacing provided between the upper casing 100 A and the abutting mount 201 . As described above, when the upper casing 100 A is inclined by about 45 degrees with respect to the lower casing 100 B, the upper casing 100 A automatically rotates up to the leftward felled-sidelong state and the rightward felled-sidelong state under the resiliently urging force of the spring 420 shown in FIG. 5 . Therefore, the user can easily fell the upper casing 100 A sideways only by holding the mobile phone in one hand, entering fingertips into the dent portions 520 , and pushing up the upper casing 100 A.
Next, a fourth embodiment according to the present invention will be described. In the fourth embodiment also, the same components as those in the first embodiment are designated by the same symbols, and description thereof is omitted. Only differences of the fourth embodiment from the first embodiment are described.
FIGS. 10A and 10B are perspective diagrams each showing a mobile phone according to this embodiment.
FIG. 10A is a perspective diagram of the mobile phone as seen from the front thereof, and FIG. 10B is its perspective diagram as seen from the side thereof.
As in the case of the mobile phone according to the first embodiment shown in FIG. 5 , in the mobile phone according to this embodiment shown in FIGS. 10A and 10B , the upper casing 100 A is resiliently urged downward by the spring 420 , and the upper casing 100 A is rotatably supported by the intermediate casing 100 C by the protrusion 310 of the upper casing 100 A getting into the longitudinal groove 210 provided in the intermediate casing 100 C. Also, in the mobile phone according to this embodiment, by the user pushing one of buttons 611 provided at the left and right ends, the upper casing 100 A rotates in a respective one of the left and right directions.
FIGS. 11A to 11C are enlarged diagrams each showing the vicinity of the buttons 611 in the mobile phone, shown in FIG. 10 .
FIG. 11A is a side view showing the vicinity of the buttons 611 in the mobile phone, FIG. 11B is a perspective diagram of the vicinity of the buttons 611 as viewed from the front thereof, and FIG. 11C is a sectional view of the vicinity of the buttons 611 as viewed from the side thereof. Meanwhile, the mobile phone according to this embodiment has a left-side component for inclining the upper casing 100 A toward the left side and a right-side component for inclining the upper casing 100 A toward the right side. However, because the left-side component and the right-side component have the same construction, only the left-side component is hereinafter described as a representative of them.
The intermediate casing 100 C includes a button claw 613 that extends from the button 611 , a button spring 612 that pulls the button claw 613 toward the button 611 , a lever 614 that rotates downward about a shaft 616 by being pushed by the button claw 613 , a leaf spring 615 that resiliently urges upward the lever 614 , a lock claw 617 attached to the front end of the lever 614 , a moving claw 618 that is inhibited from its movement by the lock claw 617 , and a pulling spring 619 that pulls the moving claw 618 in the direction of the shaft 616 . The upper casing 100 A includes an erection hole 621 into which the moving claw 618 is fitted when the upper casing 100 A is in the upright state, and a falling-sidelong hole 622 into which the moving claw 618 is fitted when the upper casing 100 A is in the leftward felled-sidelong state.
In a state where the button 611 has not yet been pushed, the moving claw 618 is kept pulled by the pulling spring 619 in the direction of the shaft 616 (the right direction in FIG. 11B ), but the moving claw 618 is inhibited from moving by being locked by the lock claw 617 and further by being fitted into the erection hole 621 of the upper casing 100 A. The upper casing 100 A is maintained in the upright state by being resiliently urged downward by the spring 420 shown in FIG. 5 .
FIGS. 12A and 12B are diagrams showing an operation when the button 611 is pushed, and FIGS. 13A and 13B , and FIGS. 14A and 14B are diagrams showing a rotational operation of the upper casing 10 A.
When the user pushes the button 611 , as shown in FIG. 12 , the lever 614 is rotated downward about the shaft 616 by the lever 614 being pushed by the button claw 613 , and the lock claw 617 gets down, whereby the lock that has inhibited the moving claw 618 is released. Upon release of the lock, the moving claw 618 is pulled by the pulling spring 619 in the right direction, in a state of being fitted in the erection hole 621 of the upper casing 100 A. As a result, as shown in FIG. 13 , a pulling force A by the pulling spring 619 outweighs a resiliently urging force B by the spring 420 (refer to FIG. 5 ), in the direction in which the upright state is maintained (refer to FIG. 5 ), whereby the upper casing 100 A is rotated leftward while the protrusion 310 is guided by the longitudinal groove 210 to thereby move upward.
Here, since the lever 614 shown in FIG. 12 is resiliently urged upward by the leaf spring 615 , the lever 614 is moved downward by the button 611 being pushed, thereby releasing the lock. Thus, when the moving claw 618 gets over the lock claw 617 , the lever 614 is moved upward, and the button 611 is returned to the original state.
When the upper casing 100 A is rotated by about 45 degrees, the moving claw 618 shown in FIG. 12 is displaced from the erection hole 621 of the upper casing 10 A, and loses its force for pulling the upper casing 100 A in the right direction. However, as shown in FIG. 14 , the spring 420 (refer to FIG. 5 ) resiliently urges the upper casing 100 A in the downward direction, which is the same as the rotational direction, and rotates the upper casing 100 A up to the leftward felled-sidelong state. When the upper casing 100 A is rotated up to the leftward felled-sidelong state, the moving claw 618 is fitted into the falling-sidelong hole 622 of the upper casing 100 A, thus inhibiting the movement of the upper casing 100 A.
In this way, according to this embodiment, the user can easily incline the upper casing 100 A only by pushing the button 611 .
When attempting to return the upper casing 100 A from the leftward felled-sidelong state to the upright state, the user should slide upward the upper casing 100 A and then rotate it in the right direction. Thereupon, the moving claw 618 is displaced from the falling-sidelong hole 622 of the upper casing 100 A to thereby be moved leftward against a pulling force by the pulling spring 619 , and in the upright state, the moving claw 618 is fitted into the erection hole 621 .
A fifth embodiment according to the present invention will now be described. Because the fifth embodiment has the same construction as that of the first embodiment except that, in the fifth embodiment, motors and the like for automatically inclining the upper casing 100 A are provided in the upper casing 100 A and the lower casing 100 B, only differences of the fifth embodiment from the first embodiment are described.
FIGS. 15A and 15B are diagrams each showing the upper casing in the mobile phone according to this embodiment, and FIG. 16 is a diagram showing the intermediate casing in the mobile phone according to this embodiment.
As shown in FIGS. 15A and 15B , the mobile phone according to this embodiment has the same protrusion 310 as that in the first embodiment shown in FIG. 4 , and further includes, on the lower side of the upper casing 100 A, pinion gears 712 , motors 711 for rotationally driving the pinion gears 712 , and inclination buttons 700 for inclining the upper casing 100 A to respective left and right directions.
Also, as shown in FIG. 16 , the mobile phone according to this embodiment includes the same longitudinal groove 210 as that in the first embodiment shown in FIG. 3 , and a rack gear 720 with which the two pinion gears mesh.
FIG. 17 is a diagram showing operations for inclining the upper casing 100 A toward the lower casing 100 B, in the mobile phone according to this embodiment.
In this embodiment, in the upright state of the upper casing 100 A (step S 31 in FIG. 17 ), the protrusion 310 is disposed at the lowest position of the longitudinal groove 210 , and the two pinion gears 712 provided in the upper casing 100 A is in a meshing engagement with the rack gear 720 provided in the intermediate casing 100 C.
When the user pushes the inclination button 700 for inclining the upper casing 100 A toward the left side, a drive instruction is issued from the CPU 110 to the motor 711 , and the motor 711 is rotationally driven in the right direction. As a result, the two pinion gears 712 are rotated and moved along the rack gear 720 in the right direction, and after the right pinion gear 712 has been displaced from the rack gear 720 , the protrusion 310 is guided by the longitudinal groove 210 , as well as the left pinion gear 712 is guided by the longitudinal groove 210 , thereby rotating the upper casing 100 A in the left direction (step S 32 in FIG. 17 ).
When the upper casing 100 A is inclined in the left direction, the upper casing 100 A is abutted against the abutting mount 201 , and the movement of the pinion gear 712 is stopped (step S 33 in FIG. 17 ).
When the user pushes the inclination button 700 for inclining the upper casing 100 A toward the right side, the motor 711 is rotationally driven in the left direction. As a result, the two pinion gears 712 are moved in the left direction, and after the left pinion gear 712 has been displaced from the rack gear 720 , the upper casing 100 A is rotated in the right direction (step S 34 in FIG. 17 ). When the upper casing 100 A is inclined up to the rightward felled-sidelong state, the movement of the pinion gear 712 is stopped (step S 35 in FIG. 17 ).
As described above, according to the mobile phone of this embodiment, the user can easily incline the upper casing 100 A only by pushing the button 611 , without applying a large force.
Next, a sixth embodiment according to the present invention will be described. In the sixth embodiment also, the same components as those in the first embodiment are designated by the same symbols, and description thereof is omitted. Only differences of the sixth embodiment from the first embodiment are described.
FIG. 18 is a diagram showing the surface side of the intermediate casing 100 C in the mobile phone according to this embodiment.
As shown in FIG. 18 , the intermediate casing 100 C according to this embodiment has a longitudinal groove 210 that vertically extends, as in the intermediate casing 100 C in the first embodiment, and further, has a V-groove 211 that extends in the left and right directions, formed below the longitudinal groove 210 . The V-groove is one example of what the present invention terms “guide groove”.
FIG. 19 is a diagram showing the back surface side of the upper casing 100 A in the mobile phone according to this embodiment.
As shown in FIG. 19 , as in the case of the upper casing 100 A in the first embodiment shown in FIG. 4 , the upper casing 100 A has an protrusion 310 to be fitted into the longitudinal groove 210 , and further, has an auxiliary protrusion 312 to be fitted into the V-groove 211 . The auxiliary protrusion 312 is one example of what the present invention terms “guide pin”.
FIG. 20 is a perspective diagram showing the upper casing 100 A, the lower casing 100 B, and the intermediate casing 100 C.
The mobile phone according to the present invention also has a spring 420 that is connected to the protrusion 310 and that resiliently urges the upper casing 100 A in the downward direction. Also, in this embodiment, the auxiliary protrusion 312 has a through-hole, and an electrical cable 410 for electrically connecting the upper casing 100 A and the lower casing 100 B is arranged through the through-hole of the auxiliary protrusion 312 . Passing the electrical cable 410 through the through-hole of the auxiliary protrusion 312 allows the prevention of breaking of the electrical cable 410 , as well.
FIGS. 21A and 21B are diagrams showing various dimensions in the mobile phone according to this embodiment.
In the mobile phone according to this embodiment, in the leftward felled-sidelong state shown in FIG. 21A , the distance B 1 between the right edge of the upper casing 100 A and the center of the protrusion 310 is made equal to the distance B 2 between the lower edge of the upper casing 100 A and the center of the auxiliary protrusion 312 , and the distance C 1 between the center of the protrusion 310 and the center of the auxiliary protrusion 312 is made equal to the distance C 2 between the center of the protrusion 310 and the center of the auxiliary protrusion 312 in the upright state shown in FIG. 20B . Also, in order to smoothly rotate the upper casing 100 A, a spacing A is provided between the lower edge of the upper casing 100 A and the abutting mount 201 . By using the upper casing 100 A and intermediate casing 100 C with such dimensions, it is possible to bring the right edge of the upper casing 100 A in line with that of the intermediate casing 100 C, in the leftward felled-sidelong state, and to bring the left edge of the upper casing 100 A in line with that of the intermediate casing 100 C, in the rightward felled-sidelong state. Furthermore, in both of the leftward felled-sidelong state and rightward felled-sidelong state, it is possible to bring the upper edge of the upper casing 100 A in line with that of the intermediate casing 100 C.
FIG. 22 is a diagram showing operations for inclining the upper casing 100 A toward the lower casing 100 B.
As shown in FIG. 21B also, when the upper casing 100 A is in the upright state (step 41 in FIG. 22 ), the protrusion 310 is located at the lowest position of the longitudinal groove 210 , and an auxiliary protrusion 313 is located at the lowest position of the V-groove 212 .
When the user inclines the upper casing 100 A toward the left side, first, the protrusion 310 moves upward under the guidance of the longitudinal groove 210 , as well as the auxiliary protrusion 312 moves upward along the right side groove of the V-groove 211 , and the upper casing 100 A starts rotating in the left direction against the resiliently urging force of the spring 420 (step S 42 in FIG. 22 ).
Upon being rotated by about 45 degrees, the upper casing 100 A is resiliently urged by the spring 420 in the same direction as the rotational direction, and the upper casing 100 A is rotated while the bottom corner thereof is guided by the abutting mount 201 , to thereby be felled sidelong leftward with respect to the lower casing 100 B (step 43 in FIG. 22 ).
On the other hand, when the user inclines the upper casing 100 A toward the right side (step 44 in FIG. 22 ), the protrusion 310 is guided by the longitudinal groove 210 and the auxiliary protrusion 312 is guided by the left side groove of the V-groove 211 and moves along it, whereby the upper casing 100 A is rotated in the right direction, and is felled sidelong rightward with respect to the lower casing 100 B (step S 45 in FIG. 22 ). Thus providing the V-groove 211 in addition to the longitudinal groove 210 allows the upper casing 100 A to be more smoothly inclined.
Next, a seventh embodiment according to the present invention will be described. Because the seventh embodiment has the same construction as that of the sixth embodiment except that the dimension of a longitudinal groove 210 in this embodiment is different from that of the sixth embodiment, only differences of the seventh embodiment from the sixth embodiment are described.
FIGS. 23A and 23B are diagrams showing various dimensions in the mobile phone according to this embodiment of the present invention.
In the mobile phone according to this embodiment, in the leftward felled-sidelong state shown in FIG. 23A , when the distance between the right edge of the intermediate casing 100 C and that of the upper casing 100 A is represented as β, and the distance between the center of the protrusion 310 and that of the auxiliary protrusion 312 is represented as J, let the distance between the right edge of the upper casing 100 A and the center of the protrusion 310 be (H+β), and let the distance between the center of the protrusion 310 and that of the auxiliary protrusion 312 in the upright state shown in FIG. 23B be (J−β). Moreover, in order to smoothly rotate the upper casing 10 A, a spacing D is provided between the lower edge of the upper casing 100 A and the abutting mount 201 . Forming the upper casing and the intermediate casing with such dimensions makes it possible, in the leftward felled-sidelong state and the rightward felled-sidelong state, to bring the upper casing 100 A close to the center and to improve the stability when the user holds the mobile phone in a hand.
FIG. 24 is a diagram showing operations for inclining the upper casing 100 A toward the lower casing 100 B.
As shown in FIG. 23B also, when the upper casing 100 A is in the upright state (step 51 in FIG. 24 ), the protrusion 310 is located at the central position of the longitudinal groove 210 , and the auxiliary protrusion 312 is located at the lowest position of the V-groove 211 .
When the user inclines the upper casing 100 A toward the left side, the protrusion 310 is guided by the longitudinal groove 210 , and the auxiliary protrusion 312 is guided by the right side groove of the V-groove 211 and moves along it, whereby the upper casing 100 A rotates in the left direction (step S 52 in FIG. 24 ).
When the upper casing 100 A is rotated up to the leftward felled-sidelong state (step 53 in FIG. 24 ), the upper casing 100 A is subjected to an interference with the abutting mount 201 , and the movement of the upper casing 100 A is stopped.
On the other hand, when the user inclines the upper casing 100 A toward the right side (step 54 in FIG. 24 ), the protrusion 310 is guided by the longitudinal groove 210 and the auxiliary protrusion 312 is guided by the left side groove of the V-groove 211 and moves along it, whereby the upper casing 100 A is rotated in the right direction and felled sidelong rightward with respect to the lower casing 100 B (step S 55 in FIG. 24 ).
In this manner, according to the mobile phone according to this embodiment, the upper casing 100 A can be brought close to the center when the upper casing 100 A is inclined.
An eighth embodiment according to the present invention will now be described. Because the eighth embodiment has the same construction as that of the seventh embodiment except that, in this embodiment, the dimension of a spacing between the intermediate casing and the intermediate casing is different from that of the seventh embodiment, only differences of the eighth embodiment from the seventh embodiment are described.
FIGS. 25A and 25B are diagrams showing various dimensions in the mobile phone according to this embodiment.
In the mobile phone according to this embodiment, when the distance between the right edge of the intermediate casing 100 C and that of the upper casing 100 A in the leftward felled-sidelong state shown in FIG. 25A is represented as α, and the distance between the center of the protrusion 310 and that of the auxiliary protrusion 312 is represented as F, and when the distance between the lower edge of the upper casing 100 A in the upright state shown in FIG. 25B and the abutting mount 201 is represented D, let the distance between the right edge of the upper casing 100 A and the center of the protrusion 310 in the leftward felled-sidelong state shown in FIG. 25A be (E+α), and let the distance between the center of the protrusion 310 and the center of the auxiliary protrusion 312 in the upright state of the upper casing 100 A shown in FIG. 25B be F. According to the mobile phone of this embodiment, when the upper casing 100 A is inclined up to the leftward felled-sidelong state or the rightward felled-sidelong state, it is possible to bring the upper casing 100 A close to the center and to raise up the upper casing 100 A.
Next, a ninth embodiment according to the present invention will be described. In the ninth embodiment of the present invention also, the same components as those in the first embodiment are designated by the same symbols, and description thereof is omitted. Only differences of the ninth embodiment from the first embodiment are described.
FIG. 26 is a diagram showing the surface side of the intermediate casing 100 C in the mobile phone according to this embodiment.
As shown in FIG. 26 , as in the case of the intermediate casing 100 C in the first embodiment shown in FIG. 3 , the intermediate casing 100 C in this embodiment has a longitudinal groove 210 that vertically extends, and further has an auxiliary protrusion 313 that protrudes toward the lower casing 100 B. This auxiliary protrusion 313 is also one example of what the present invention terms “guide pin”.
FIG. 27 is a diagram showing the back surface side of the upper casing 100 A in the mobile phone according to this embodiment.
As in the case of the upper casing 100 A in the first embodiment shown in FIG. 4 , the upper casing 100 A in this embodiment has a protrusion 310 to be fitted into the longitudinal groove 210 , and further has an arcuate groove 212 into which the auxiliary protrusion 313 is to be fitted. The arcuate groove 212 has a shape such that bilaterally symmetrical two arc-shaped grooves are connected at the center of the arcuate groove. This arcuate groove 212 is also one example of what the present invention terms “guide groove”.
FIG. 28 is a diagram showing operations for inclining the upper casing 100 A toward the lower casing 100 B.
When the upper casing 100 A is in the upright state (step 61 in FIG. 28 ), the protrusion 310 is located at the lowest position of the longitudinal groove 210 , and an auxiliary protrusion 313 is fitted in the central position of the arcuate groove 212 .
When the user inclines the upper casing 100 A toward the left side, first, the protrusion 310 is guided by the longitudinal groove 210 to thereby vertically moves, and the left side groove of the arcuate groove 212 slides with the auxiliary protrusion 313 fitted-in, whereby the upper casing 100 A rotates in the left direction (step S 62 in FIG. 28 ).
In the leftward felled-sidelong state in which the upper casing 100 A is felled sidelong leftward with respect to the lower casing 100 B (step 63 in FIG. 28 ), the protrusion 310 has been moved to the lowest position of the longitudinal groove 210 , and the auxiliary protrusion 313 is fitted in the front end of the left side groove of the arcuate groove 212 .
On the other hand, when the user inclines the upper casing 100 A toward the right side (step 64 in FIG. 28 ), the protrusion 310 is guided by the longitudinal groove 210 , and the right side groove of the arcuate groove 212 slides with the auxiliary protrusion 313 fitted-in, whereby the upper casing 100 A rotates in the right direction (step S 65 in FIG. 28 ). As described above, using the arcuate groove instead of the V-groove allows the upper casing 100 A to be smoothly inclined, as well. Furthermore, sliding the groove with the auxiliary protrusion fitted-in instead of moving the auxiliary protrusion along the groove allows the upper casing 100 A to be rotated, as well.
Hereinbefore, examples in which the mobile terminal device according to the present invention is applied to mobile phones have been described, but the mobile terminal device according to the present invention may be applied to a personal digital assistant (PDA) and so on.
Also, in the forgoing description, examples in which the longitudinal groove is provided in the intermediate casing, and the protrusion is provided in the upper casing have been explained. However, the vertical groove termed by the present invention may be provided in the upper casing instead of the intermediate casing, and the protrusion termed by the present invention may be provided in the intermediate casing instead of the upper casing.
Besides, the hinge portion termed by the present invention may be configured integrally with the intermediate casing or the lower casing, or alternatively, may be configured as a hinge module, individually of the casings. | According to an aspect of an embodiment, a mobile terminal device includes a lower casing, an upper casing, and an intermediate casing, an intermediate casing connected to the lower casing by a hinge structure which enables the intermediate casing to rotate about an axis, the intermediate casing supporting a back surface of the upper casing by a front surface of the intermediate casing, wherein the upper casing has a first groove formed in a vertical direction with respect to the rotation axis on a surface facing the intermediate casing, the intermediate casing has a first portion protruding from a surface facing the upper casing and fitting the groove of the upper casing, and the upper casing is rotatable with respect to the intermediate casing for the portion being guided by the groove. | 7 |
[0001] The present application claims priority on U.S. Provisional Application Serial No. 60/189,618 filed Mar. 15, 2000.
FIELD OF THE INVENTION
[0002] The present invention relates to improvements in a cutting tool of the plier type which is commonly used to cut various materials of differing shape and hardness.
BACKGROUND OF THE INVENTION
[0003] Cutting tools of the plier type similar to the present invention are now in widespread use. Cutting pliers utilizing diagonal and straight jaws are used to cut multiple shapes of various materials. However, when they need to cut a geometric shape such as a ring encircling tubing, the cut needs to be done with the extreme edge of the jaws.
[0004] This explains why plumbers and other persons have been using hacksaws for over twenty years to cut off compression rings of medium strength materials such as copper or aluminum. Indeed, many plumbers will cut the flexible pipe and throw away the fittings to avoid the difficulties of cutting a ring with currently available tools.
[0005] Other proposed systems to cut these rings have included the use of a roto-tool with a cutting wheel. A tool bit closing tool has also been developed for cutting such rings. These two systems to cut the rings from a water pipe or conduit are more complicated, more costly, and do not provide the capability to extract the ring after it is cut. Also, the devices do not necessarily provide multiple size cutting capability.
SUMMARY OF THE INVENTION
[0006] It is an object of the present invention is to provide a simple, reliable, and versatile hand tool which permits plumbers and other users to cut a copper or similar ring surrounding a conduit when such action is needed. Examples of the use of such rings include their use on current water lines, cutting off plugs after pressure testing, or dismantling a fitting.
[0007] A second object of the present invention is to provide a ring cutting tool in which the jaws and cutting edge geometry permit an easy lateral cutting and breaking apart of a compression ring in a first motion, and its pulling away from the pipe in a second motion.
[0008] A third object of the present invention is to permit the operator of the tool to pull off the cut ring through a second operation simply by using the ring cutting tool to “bite” the ring near the cut area and pull on the tool to unroll and free up the ring.
[0009] A fourth object of the present invention is to provide a ring cutting tool which can be used with any size of ring since the cut is done laterally from edge to edge. A still further object of this invention is to combine the previous noted advantages of the ring cutting tool which incorporates other functions such as a hammer, wire cutters, pliers, etc.
[0010] A still further object of the present invention is to provide a ring cutting tool which can be manufactured in a similar manner as current plier tools.
[0011] According to one aspect of the present invention, there is provided a ring cutting tool suitable for cutting a ring from tubing, the ring cutting tool comprising a first member having a first member jaw at one end thereof and a first member handle at an opposed end thereof, a second member having a second member jaw at one end thereof and a second member handle at an opposed end thereof, the first jaw having a first jaw cutting surface formed thereon, the second jaw having a second jaw cutting surface formed thereon, the first and second members being pivotably connected together such that the first jaw cutting surface and the second jaw cutting surface can move from a first spaced apart position to a second position wherein the jaw cutting surfaces are in a substantially abutting relationship and the first jaw cutting surface and the second jaw cutting surface defining an angle of between 20° and 35° when in the second position.
[0012] The cutting tool of the present invention may have the same general characteristics of current cutter pliers providing a mechanical advantage of 5 to 7, where 40 to 50 lbs. of handle pressure provide 200 to 350 lbs. of force at the tip of the jaws, which is sufficient to cut through any copper ring used currently in flexible water line. Those copper rings with a thickness of 0.050 inch to 0.060 inch and a width of {fraction (5/16)} inch to ⅜ inch may easily be cut by the tool of the present invention with a single closure of the jaw across the ring.
[0013] As aforementioned, the ring cutting tool of the present invention is suitable for cutting rings surrounding a conduit. In order to achieve the above, the blades have a geometry which permits the blades to bite into the ring and not slip therefrom.
[0014] It is preferred that the jaw cutting surfaces, in the preferred embodiment, and when in a closed relationship, define an angle of between 20° and 35° . Even more preferably, the angle is between 25° and 30°. It is also preferred that the edges of the jaw adjacent the conduit slope backward therefrom to provide sufficient clearance. The angle of slope is preferably between 5° and 25° and even more preferably, between 8° and 15°.
[0015] The ring cutting tool of the present invention may incorporate many conventional abilities therein. Thus, the two jaws may have the capability of functioning as a hammer and/or claw. Even further, there may be provided the capability, as will be discussed in the preferred embodiments, of the tool functioning as a wire cutter, a conventional plier, etc.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Having thus generally described the invention, reference will be made to the accompanying drawings illustrating an embodiment thereof, in which:
[0017] [0017]FIG. 1 a is a side view of a ring cutting tool in accordance with a first embodiment of the invention, the tool being shown ready to cut a ring;
[0018] [0018]FIG. 1 b is a side view of the ring cutting tool of FIG. 1 a after cutting through the ring;
[0019] [0019]FIG. 1 c is a top view of the ring after it has been cut;
[0020] [0020]FIG. 2 a is a side view of a ring cutting tool prior to cutting a ring in accordance with a second embodiment of the present invention;
[0021] [0021]FIG. 2 b is a side view of the ring cutting tool of FIG. 2 a after cutting through the ring;
[0022] [0022]FIG. 3 a is a side view of a ring cutting tool in accordance with a third embodiment of the invention;
[0023] [0023]FIG. 3 b is a front view of the ring cutting tool of FIG. 3 a ;
[0024] [0024]FIG. 3 c is a view along line 2 - 2 of FIG. 3 a ; and
[0025] [0025]FIG. 3 d is a view along line 3 - 3 of FIG. 3 b.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0026] A first embodiment of the ring cutting tool of the present invention is shown in FIG. 1 a to 1 c and will now be referred to in greater detail. FIG. 1 a is a side view of a portion of tool 8 is positioned to start cutting a ring 30 . FIG. 1 b shows the ring cutting tool in its fully closed position at the end of the cutting operation. FIG. 1 c shows the cut copper ring after the ring cutting tool is reopened and pulled away from the ring.
[0027] The ring cutting tool 8 shown in FIG. 1 a has a configuration that is customary in most medium and heavy duty plier-type tools. A first member is comprised of a handle 10 and a hammer jaw 14 and a second member is comprised of a handle 12 and a puller jaw 16 ; the two members are operatively connected through a fastener 18 . Fastener 18 is a heavy rivet pin or alternatively could be a hardened bolt and locknut. Cutting edges 20 and 22 are provided on jaws 14 and 16 respectively. As will be discussed hereinbelow, the geometry and hardness of these cutting edges are important in providing the cutting capability of tool 8 . Front stoppers 24 and rear stoppers 26 are provided to limit the rotational closure of the jaws 14 and 16 and therefore prevent the cutting edges 20 and 22 from contacting each other.
[0028] The fabrication of the ring cutting tool 8 may be similar to that of many plier-type tools. First, an alloy or carbon steel is cast or forged. Then machining is performed while the steel is in a soft temper (well annealed). The tool is then hardened and tempered in order to achieve Rockwell C hardness of around 54 - 58 . This is followed by an application of black oxide or other rust prevention treatment. The final steps in the fabrication of the ring cutting tool are grinding and sharpening the cutting edges, polishing, coating the handles for comfort (plasticoat), and assembling (using rivets or a bolt and nut assembly). The front clearance, edge angle, backward slope of the cutting angle and tool hardness are features of the present invention that will be discussed hereinbelow and that facilitate easy repetitive cutting of any size copper ring or other similar connection used on a flexible pipe. All fabrication methods and techniques used in the construction of the ring cutting tool are current technologies.
[0029] A second embodiment of the present invention is shown in FIG. 2 a which is a side view of the ring cuffing tool at the start of the ring cutting operation. FIG. 2 b shows a side view of the second embodiment of the tool at the end of the cutting stroke. This embodiment is a lighter and simpler ring cutting tool than the first embodiment. There is no hammer or puller jaw in this configuration.
[0030] The ring cutting tool of FIG. 2 a has two handles 42 and 44 directly connected to cutting edges and jaws 50 and 48 respectively. Arm 42 and jaw 50 are operatively connected to arm 44 and jaw 48 by a fastener 58 . Stopper surfaces 46 are shown apart since the ring cutting tool is open at the start of the ring cutting operation.
[0031] Pipe fitting 56 is fitted inside a flexible pipe 52 and is shown being sealed around fitting 56 by a copper ring 54 which has been previously crimped. The ring cutting tool is shown pressing against the flexible pipe 52 in order to achieve a clean cut.
[0032] This second embodiment of the ring cutting tool is shown as a side view in FIG. 2 b when the tool has cut through the copper ring 54 . Handles 40 and 42 are now in closed position, as are the jaw and cutting edges 48 and 50 . Stopper surfaces 46 are now abutting each other.
[0033] Fabrication of the tool shown in FIG. 2 a is similar to the main embodiment shown in FIG. 1 a.
[0034] A third embodiment of the ring cutting tool incorporates three extra features: a wire cutting capability, a rear plier capacity, and a ring punching cavity. This embodiment is shown in FIG. 3 a which is a side view of the ring cutting tool. A front view of the jaws along line 1 - 1 is shown in FIG. 3 b . A cross section of the rear plier jaws is shown in FIG. 3 c along the line 2 - 2 . FIG. 3 d shows a view of the cutting edge along line 3 - 3 of FIG. 3 b.
[0035] The ring cutting tool of FIG. 3 a following a third embodiment has two handles 62 and 64 directly connected to jaws 78 and 80 . These two parts of the ring cutting tool are operatively connected and are held together with precision by a bolt and locknut fastener 72 . Handle 64 is directly linked to hammer jaw 80 and directly in line with cavity 90 and hammering handle end 96 . A cutting edge 70 provides a wire cutting capability. Notches 98 allow the tool to cut heavy wire. This embodiment has rear plier capability through jaws 66 and 68 . One other feature of the third embodiment is the ring cavity 90 with punching edges 94 which allows the plumber to deform the flexible tubing before attempting to cut the copper ring when needed.
[0036] Stopper surfaces 74 prevent the front jaws from completely closing and damaging the cutting apex 92 of cutting edges 76 and 82 . Cutting edges 76 and 82 require a cutting angle 84 of around 20° to 35°. It is to be noted that the cutting jaws have a front clearance shown by number 88 which preferably is between 5 and 20° and even more preferably between 8° and 15°.
[0037] As seen in FIG. 3 a , there is an upper claw jaw 78 and a lower hammer jaw 80 having cutting edges 76 and 82 respectively. The front view of the tool shows the narrow edges 94 and the cavity 90 . The width of the cutter edge 98 is preferably between 0.01 and 0.10 inches. The angle of the cutting edges 76 and 82 as above mentioned is indicated by the extended lines 86 and is preferably between 20° to 35° and more preferably between 25° to 30°.
[0038] [0038]FIG. 3 c shows a cross section of the double jaws 66 and 68 along line 2 - 2 of FIG. 3 a . Details of the cutting edge 76 of jaw 78 are shown in FIG. 3 d , taken along line 3 - 3 of FIG. 3 b . Shown in this figure are the rotating section of handle 64 , the stopper surface 74 , the cutting edge 76 , and apex of the cutting edge 92 .
[0039] The fabrication of the third embodiment of the invention is similar to the first and second embodiments.
[0040] The ring 30 to be cut and removed is shown in FIG. 1 a . The flexible pipe 28 is engaged around the fitting 32 , and the copper ring 30 has been previously crimped to seal the flexible pipe 28 to the fitting 32 . To begin the ring cutting operation, the tool 8 is held in an open position. FIG. 1 a shows a side view of the tool positioned to start the ring cutting operation. The cutting edges of the tool are pressed against the flexible tubing with the copper ring between the apex of the cutting surfaces. The tool handles 10 and 12 are pressed together with approximately 50 to 60 lbs. of pressure. As the handles are closed, the tool can be twisted to open the ring up to around ¼″. FIG. 1 b shows the ring cutting tool 8 in a fully closed position at the end of the cutting operation. FIG. 1 c shows the cut copper ring after the ring cutting tool is reopened and pulled away from the ring. Surfaces 36 show the cuts done by cutting edges 20 and 22 . There is a deformation angle of between about 20° to 40° which is approximately the same as the angle of the cutting edges. A center surface 38 is very small, around 10% of the original width of the ring. This surface is not cut, but broken away from the other side by the closure of the tool.
[0041] The cutting edge of the tool can be used to cut the copper ring in a second place, causing the ring to fall off in two pieces. Or, instead of cutting the ring twice, after the first cut, the front cutting jaw can be used as an ordinary plier to bite into one side of the ring and simply pull it farther open and remove it. An ordinary screwdriver can also be used to pull the ring off after the first cut.
[0042] While several embodiments of the invention have been shown and described, it is to be clearly understood that the invention is not to be limited to the exact construction illustrated and described. But instead, that many alterations and modifications are possible in the practice of this invention without departing from the spirit or scope thereof. Accordingly, the scope of the invention is to be construed in accordance with the substance defined by the following claims. | A ring cutting tool for cutting a ring which encircles tubing, the ring cutting tool having a first member with a jaw at one end and a handle at the other end, a second member having a jaw at one end thereof, and a handle at the other end thereof, the first and second jaws being in a substantially abutting relationship when in a closed position, the jaws providing jaw cutting surfaces which define an angle of between 20° and 35°. The ring cutting tool permits an easy lateral cutting and breaking apart of a compression ring. | 1 |
The present disclosure relates to the subject matter disclosed in PCT Application No. PCT/EP96/02183 of May 21, 1996, the entire specification of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
This application is a continuation of International PCT Application No. PCT/EP96/02183 filed on May 21, 1996.
The invention relates to a piping comprising at least one pipe and a reinforcement arranged on an outer wall of each pipe.
Such pipings are known in large numbers from prior art.
Pipings comprising glass pipes provided with a metal jacket reinforcement or a plastic coating are known in particular.
Such metal or plastic reinforcements are provided in order to protect the piping from external damage, resulting e.g. from a foreign body impacting it. They are not however capable of substantially increasing the internal compressive load which the piping can be expected to bear.
Particularly for pipings with pipes made of a brittle material such as glass, which can only be loaded in tension to a limited extent, it would however be desirable considerably to increase the permissible internal compressive load, in order to open up new applications for such pipings in the high-pressure range.
The problem underlying the invention was therefore to improve a piping of the above type so as to increase the maximum internal pressure at which the piping can be operated.
SUMMARY OF THE INVENTION
In a piping of that type the problem is solved, in that the reinforcement can be expanded longitudinally of the pipe and has a transverse contraction capacity such that a compressive bias around the circumference of the pipe can be applied to the pipe by expanding the reinforcement longitudinally of the pipe.
The concept of the invention thus offers the advantage that a compressive bias can be applied to each pipe in the line through transverse contraction of the reinforcement supported on the outer wall of the pipe as a result of longitudinal expansion thereof, the bias being opposed to the tensile stress on the pipe around the circumference, caused by the internal operating pressure of the piping.
Particularly in brittle materials such as glass the compressive strength is far greater than the tensile strength, and consequently the compressive bias can readily be chosen so that it compensates for the tensile stress around the circumference of the pipe caused by a considerable internal operating pressure (e.g. 40 bar with an inside diameter of 150 mm), without any fear of the piping failing if the internal pressure should drop.
Another advantage of the piping according to the invention is that, should the pipes fail, they will not break disastrously but merely form short cracks, through which the fluid contained in the piping can only escape in small volumes and through which the internal pressure can only drop gradually, thus leaving adequate time for damage limitation.
When the reinforcement is expanded longitudinally of the pipe, it is shrunk onto it by transverse contraction and supported by the pipe, and hence a reinforcement arranged on the pipe sets up greater resistance to longitudinal expansion than the same reinforcement would without the supporting pipe. This effect will hereinafter be referred to as impedance of transverse contraction.
The elasticity of the reinforcement when expanded longitudinally of the pipe with impedance of transverse contraction is greater than its elasticity without such impedance. The increase corresponds to the compressive biassing of the pipe around the circumference.
In order to enable a desired expansion of the reinforcement and thus a desired compressive bias to be produced with the lowest possible stresses, it is therefore advantageous that, on expansion of the reinforcement longitudinally of the pipe without any impedance of transverse contraction, the elasticity of the reinforcement should be at the most approximately equal to its elasticity on expansion of the reinforcement longitudinally of the pipe with transverse contraction impeded by the pipe.
It is particularly beneficial that the elasticity of the reinforcement without any impedance of transverse contraction should be at the most approximately half and preferably at the most approximately one-tenth of the elasticity of the reinforcement with transverse contraction impeded.
Ideally the elasticity of the reinforcement without impedance of transverse contraction would be zero, since all the stress applied to expand the reinforcement would then be converted to a compressive bias on the pipe.
In order to facilitate the longitudinal expansion and accompanying transverse contraction of the reinforcement but to prevent it from slipping along the piping, it is advantageous for the reinforcement to be fixed relative to the pipe and longitudinally thereof in fixing areas spaced apart longitudinally of the pipe, and to be capable of sliding over the outer wall of the pipe between the fixing areas.
It is particularly beneficial if the transverse contraction number of the reinforcement is a minimum of approximately 0.4 and preferably a minimum of approximately 0.1.
The reinforcement advantageously has at least one aperture. The outside wall of the pipe is accessible through such an aperture, so that its condition can be checked while the piping is in operation.
If the pipe is itself made of a transparent material such as glass, the transparency is retained by virtue of the aperture in the reinforcement; this brings the advantage that the filling level of a fluid contained in the piping can be checked from outside.
It is beneficial for the reinforcement to be pre-expanded longitudinally of the pipe, and for a compressive bias around the circumference of the pipe to be applied to the pipe through the pre-expansion of the reinforcement. The meaning of the term "pre-expansion" is an expansion of the reinforcement longitudinally of the pipe, which is already present when the piping is not under an internal compressive load, i.e. which is not caused only by longitudinal expansion of the pipe as a result of the internal operating pressure. Such pre-expansion enables any optional compressive bias to be applied to the pipe around its circumference, even in its inoperative state without any internal pressure.
It is particularly beneficial for the compressive bias of the pipe around the circumference to be opposed and substantially equal to the tensile stress on the pipe in that direction, caused by the internal operating pressure on the pipe. The effect of this is that, at the operative internal pressure which prevails during normal operation, the compressive bias and the tensile stress on the pipe around the circumference just counterbalance each other, so that the pipe is stress-free in that direction. In such a stress-free condition the pipe is particularly resistant to external damage.
As a means of expanding the reinforcement longitudinally of the pipe, the piping advantageously has force introduction means for admitting force to the reinforcement longitudinally of the pipe.
A structurally inexpensive construction for the piping is obtained if the reinforcement is at the same time fixed relative to the pipe by the force introduction means, thus preventing it from slipping along the piping.
Particularly simple introduction of a longitudinal force into the reinforcement to expand it longitudinally can be obtained, if the reinforcement contains apertures into which force introduction elements of the force introduction means engage.
Provision may particularly be made for the force introduction elements to form a positive connection with the reinforcement, which connection fixes the reinforcement longitudinally of the pipe relative to the force introduction elements. A positive connection of this type between the reinforcement and the elements is reliable and inexpensive to make.
The force introduction elements may form the positive connection with edgings of apertures in the reinforcement.
It is particularly beneficial, however, for the force introduction elements to form the positive connection together with edgings of apertures in the reinforcement and with positive connection elements, which are arranged between the force introduction elements and the edgings and made of hardened material, the hardened material being inserted in pasty or fluid form. With positive connection elements of this type, surface contact of all the members involved in the connection can be obtained, even when the geometry of the force introduction elements does not specially match that of the edgings of the apertures. It is also possible to vary the position of the force introduction elements relative to the edgings of the apertures when assembling the piping, as different spacings between those elements and the edgings are compensated for by the positive connection elements arranged between them. This allows larger tolerances in both the manufacture of the reinforcement and the assembly of the piping, thus saving time and expense and allowing greater flexibility in the make-up of the piping.
The force introduction means of a pipe are advantageously arranged at an end portion of the pipe. With such an arrangement the force introduction means can not only fulfil their function of admitting force into the reinforcement longitudinally of the pipe; they can also take over the additional function of interconnecting adjacent pipes or connecting the piping with other components of an installation including the piping.
No details have yet been given of the make-up of the force introduction means.
In a preferred embodiment of the piping according to the invention the force introduction means of a pipe comprise at least one flange element, to which the force introduction elements are attached.
It is particularly beneficial if a force in the longitudinal direction of the pipe can be directed into the flange element, for example by fastening the flange element to another member of the piping.
If the force introduction means of a pipe are additionally to take over the function of a pipe connection at which two pipes adjoin, it is advantageous for the piping to include a flange element to which force introduction elements of one pipe and of the other pipe are attached.
Alternatively or in addition to this arrangement, the piping may comprise a first flange element to which force introduction elements of one pipe are attached, and a second flange element to which force introduction elements of the other pipe are attached, the first flange element and the second flange element being capable of being attached to each other an adjustable distance apart longitudinally of the pipes. In this embodiment the reinforcements of the two pipes involved in the pipe connection can be expanded longitudinally of the pipes by reducing the distance between the first and second flange element.
In order that the extension of the reinforcement longitudinally of the pipe or the length of the reinforced pipe need not be designed for use in a piping of predetermined geometry at the production stage, it is advantageous for the reinforcement to have apertures arranged in a substantially periodic pattern longitudinally of the pipe. The reinforcement or reinforced pipe may in that case be shortened to the required length during assembly of the piping, and a plurality of pipe lengths can be made, the lengths differing by an integral multiple of the periodicity length of the periodic pattern of the apertures.
It is thus possible in particular to manufacture the reinforcement or reinforced pipe continuously in an automated production process, and only to cut it into lengths in the required manner during assembly of the piping.
In order to have a narrow enough raster of feasible pipe lengths available, it is beneficial for the pattern of apertures to have a periodicity length less than approximately one-fifth and preferably less than approximately one-tenth of the circumference of the pipe.
Flexibility in forming the piping is further increased if the pattern of apertures is made up of a plurality of component patterns which are substantially periodic longitudinally of the pipe and which have substantially the same periodicity length, the apertures in one respective component pattern being offset from the apertures in the other component patterns longitudinally of the pipe, by a distance shorter than the periodicity length of the component patterns. In this case the distance between successive available pipe lengths is shorter than the periodicity length of the entire pattern of apertures, since the apertures in the component pattern which are most suitable according to the pipe length can be used e.g. to form a positive connection with the force introduction elements of the force introduction means.
If there are two component patterns offset longitudinally of the pipe by a distance equal to half the periodicity length of one component pattern, all pipe lengths which differ from each other by a multiple of half the periodicity length will then be available.
In a preferred embodiment of the piping according to the invention the reinforcement comprises a lattice of intersecting lattice bars expanding along the outer wall of the pipe. With a lattice of this type any transverse contraction numbers can in principle be obtained by suitably directing the lattice bars. Moreover the transverse contraction number of a lattice can be adjusted more easily and more exactly than that of a homogeneous shell structure. In addition, the lattice is expanded longitudinally of the pipe primarily through shear deformation and longitudinal expansion of the lattice bars rather than through bending deformation of the bars. The lattice material is therefore stressed substantially in one direction only, that of the bars, so the full unidirectional strength of the material can be utilized.
As the lattice in itself, unsupported internally on the outer wall of the pipe, would set up little resistance to a change of length owing to shearing effects, that it to say, as it has only relatively little elasticity, the lattice material is substantially subjected only to stresses which are necessary to produce the desired compressive bias on the pipe around the circumference.
Another advantage of the lattice is that its structure may be an open one with a very high superficial proportion of apertures, so that the pipe reinforcement can be comparatively light, using little material, and can thus be produced costeffectively.
A lattice of this type can be made particularly easily in a manual or automatic wrapping process if it comprises families of lattice bars, the bars of each family being aligned parallel with the bars of the same family and crossing the bars of other families.
The families of lattice bars are preferably associated in pairs, the bars of one family of a pair and the bars of the other family being aligned at equal, opposing angles to the longitudinal direction of the pipe. The effect is that the lattice and thus the compressive bias distribution created in the pipe are rotationally symmetrical relative to the longitudinal axis of the pipe.
The simplest way of controlling the transverse contraction behavior of the lattice and the most cost-effective way of manufacturing it is for the lattice to comprise only two families of lattice bars, the bars of one family and the bars of the other family preferably being aligned at equal, opposing angles to the longitudinal direction of the pipe.
It is especially beneficial for the opposing equal angle to be approximately 58 to 68°, particularly approximately 63.5°.
It should be pointed out here that the angles mentioned above and below refer in each case to the smaller of the two angles which the lattice bars form with the longitudinal direction of the pipe.
If the two families of lattice bars are at opposing equal angles of approximately 63.5° to the longitudinal direction of the pipe, the transverse contraction number of the lattice will be approximately 0.5.
Vector resolution of the forces transmitted along the lattice bars into components in the longitudinal and the circumferential direction of the pipe shows that in this case the forces transmitted around the circumference are approximately twice as strong as those in the longitudinal direction. The compressive bias around the circumference of the pipe which can be produced in the pipe by means of the lattice is consequently approximately twice as strong as that in the longitudinal direction. On the other hand, according to the well-known boiler formula, the ratio of tensile stresses in the circumferential and the longitudinal direction of the pipe, produced by an internal operating pressure in the pipe, is also 2:1, and hence the tensile stresses thus produced can, with the given lattice geometry, be compensated for by suitable longitudinal expansion of the lattice in the circumferential and longitudinal direction of the pipe simultaneously, so that the pipe is ideally free of stress in the circumferential and longitudinal direction.
The local longitudinal expansion of the reinforcement (the lattice) and thus the compressive bias applied to the pipe may be undesirably reduced by friction between the reinforcement and the outer wall of the pipe.
If the reinforcement is fixed on the pipe in fixing areas, the compressive bias may in particular diminish towards a central area of the pipe between the fixing areas.
As a means of reducing this undesirable effect, in a lattice comprising two families of bars aligned at opposing equal angles to the longitudinal direction of the pipe, the opposing equal angles may advantageously vary along the pipe.
Thus it is beneficial for the opposing equal angle to increase uniformly from one fixing area of the pipe to the next.
It is especially beneficial for the opposing equal angle to increase uniformly from the fixing areas of the pipe to the central area of the pipe between the fixing areas thereof.
In areas where the opposing equal angle to the longitudinal direction of the pipe is small the effect of friction on longitudinal expansion of the lattice is reduced, while in areas where it is large the compressive bias which can be applied to the pipe around the circumference is greater.
By reducing the opposing equal angle near the fixing areas of the pipe, greater local longitudinal expansion can therefore be transferred to the central area of the pipe.
No details have yet been given of the material of which the reinforcement of the piping according to the invention is made.
It is advantageous for the reinforcement to consist at least partiy of a fibre composite. Where such composites are used it is possible, by varying the stiffness and orientation of the fibres, to affect the transverse contraction behavior of the reinforcement and, even with a homogeneous shell structure, to obtain transverse contraction numbers up to 2.0. If a reinforcement in the form of a lattice is used there is the added advantage that fibre composites have particularly high unidirectional strength in the direction of the fibres.
It is advantageous for the reinforcement to consist at least partly of carbon fibres, as a means of obtaining particularly high strength for it, with comparatively low weight.
If the reinforcement alternatively or additionally consists at least partly of glass fibres production costs can be saved, provided that the mechanical demands on it are not too high.
As already mentioned, the compressive bias applied to the pipe may be undesirably reduced by friction between the reinforcement and the outer wall of the pipe.
It is therefore advantageous if a lubricant to reduce the friction, for example a creep oil, is arranged between the reinforcement and the outer wall of the pipe.
The surface of the reinforcement facing towards the outer wall of the pipe may in particular be provided with a lubricant.
Alternatively or in addition, a lubricant may be embedded in a matrix of the reinforcement surrounding the fibres.
By virtue of the ratio of tensile stresses in the circumferential and longitudinal direction of the pipe, produced by internal pressure in the pipe as predetermined by the above-mentioned boiler formula, the tensile stress occurring around the circumference generally limits the ability of the piping to be loaded internally in compression.
However, in order to avoid a catastrophic bursting action still better should the pipe fail, and in order to make the piping more resistant to external damage, e.g. through a foreign body impacting it, it is advantageous if a compressive bias longitudinally of the pipe can additionally be applied to the pipe. This bias compensates at least partly for the tensile stress longitudinally of the pipe produced by the internal operating pressure.
It is particularly beneficial for a compressive bias longitudinally of the pipe to be applied to the pipe, the bias being opposite and substantially equal to the tensile stress on the pipe longitudinally thereof, caused by the internal operating pressure on the pipe, since a stress-free condition of the pipe in its longitudinal direction is thereby obtained.
Other features and advantages of the invention are the subject of the following description and drawings of an example.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of a piping according to the invention with two pipe connections;
FIG. 2 is a cross-section through the piping taken along the line 2--2 in FIG. 1;
FIG. 3 is a fragment of a development of the piping according to the invention in the region I in FIG. 1;
FIG. 4 is a fragment of a development of the piping according to the invention in the region II in FIG. 1;
FIG. 5 is a longitudinal section, taken along the line 5--5 in FIG. 1, through a pipe connection in the piping according to the invention, and
FIG. 6 is a longitudinal section, taken along the line 6--6 in FIG. 1, through a pipe connection in the piping according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
A piping according to the invention, illustrated in FIGS. 1 to 6 and referred to generally as 20, comprises a plurality of hollow cylindrical, coaxial pipes 22 of equal diameter arranged axially one behind the other.
Each of the pipes 22 may, for example, be made of a brittle, fragile material such as glass.
A reinforcement is arranged on an outer wall 24 of each pipe 22, in the form of a lattice 26 lying on the wall 24.
As can be seen best from the development in FIG. 3, each lattice 26 includes a first family 28 of a plurality of lattice bars 30, e.g. ten bars, which surround the respective pipe 22 helically and which are aligned at a constant angle of plus about 63° to the direction of the longitudinal axis 32 of the pipes 22.
The lattice bars 30 of the first family 28 are parallel and equidistant from each other.
The lattice 26 further includes a second family 34 of a plurality of lattice bars 36, e.g. again ten bars, which surround the respective pipe 22 helically and which are aligned at a constant angle of minus about 63° to the direction of the longitudinal axis 32 of the pipes 22.
The lattice bars 36 of the second family 34 are also parallel and equidistant from each other.
The lattice bars 30 of the first family 28 cross the lattice bars 36 of the second family 34 at lattice nodes 38. A section of a bar 30 or 36 fixed between a pair of nodes 38 will henceforth be referred to as a lattice brace 40. Four respective nodes 38 and the four braces 40 arranged between them bound a substantially lozenge-shaped lattice aperture 42.
Owing to the alignment of the lattice bars 30, 36 described above, each of the lattice apertures 42 has a first diagonal 44 in the longitudinal direction of the pipes 22 and a second diagonal 46 in their circumferential direction; the length of the second diagonal 46 is approximately twice that of the first diagonal 44.
As can best be seen from FIG. 3, the lozenge-shaped apertures 42 form two periodic component patterns 47a and 47b longitudinally of the pipe 22, the periodicity length of each component pattern 47a, 47b corresponding to the distance between two successive lattice nodes 38 longitudinally of the pipe 22, and the apertures 42 in one pattern 47a being offset from those in the other pattern 47b longitudinally of the pipe 22, by a distance equal to half the periodicity length.
The lattice bars 30, 36 are preferably made of a fibre composite comprising e.g. carbon or glass fibres. The use of glass fibres lowers material costs, while if carbon fibres are used in a lattice 26 of the same weight higher strength and rigidity can be obtained than with glass fibres, or higher rigidity can be obtained in a lattice of lower weight and the same strength.
The lattices 26 may be produced on the actual pipes 22 to be reinforced, by winding the fibres onto the outer wall 24 of the respective pipe 22 in the direction of the lattice bars 30, 36. It is beneficial to wind them so that a fibre of a bar 30 of the first family 28 and a fibre of a bar 36 of the second family 34 alternately intersect at the lattice nodes 38.
Particularly if the lattices 26 are to be made by a manual winding process it is beneficial to arrange lozenge-shaped mouldings, e.g. wax mouldings, on the outer wall 24 of the pipe 22 in the positions envisaged for the lattice apertures 42 before the winding operation, so that passages to receive the fibres to be wound on are formed between the wax mouldings.
The winding operation is followed by a heat ageing process, in the course of which the wax mouldings used can possibly be removed by melting.
Instead of the lattice 26 being made on the actual pipe 22 to be reinforced, it may be produced by winding onto another winding frame then pulled onto the pipe 22.
As a means of fixing the lattices 26 to the end portions of the pipes 22 and coupling pairs of pipes 22 together, the piping 20 has pipe connections referred to generally as 48 and shown in detail in FIGS. 4 to 6.
Each of the pipe connections 48 comprises a substantially hollow cylindrical, first flange element 50, concentrically surrounding an end portion of the first of the pipes to be coupled (referred to as 22a in FIGS. 4 to 6), and a substantially hollow cylindrical, second flange element 52, concentrically surrounding an end portion (facing towards the first pipe 22a) of the second of the pipes to be coupled (referred to as 22b in FIGS. 4 to 6). The flange elements 50 and 52 are represented in broken lines in the development shown in FIG. 4.
The inside of the first flange element 50 carries an annular projection 54 of rectangular cross-section, engaging in a gap 56 between the pipes 22a and 22b.
The projection 54 in turn carries an annular seal 58 of substantially U-shaped cross-section, of which the underside 60 facing away from the projection 54 is flush with the inner walls 62 of the two pipes 22a and 22b; the side surfaces 64 of the seal 58 lie against the ends of the pipes 22a and 22b, so that the seal shuts off the inside of the pipes 22a and 22b tightly from the outside thereof.
The first flange element 50 contains a plurality of tapped holes 66, e.g. ten holes, arranged equidistant from each other along its circumference and passing through the element 50 in a radial direction.
A fixing pin 70 with external thread is screwed into each of the tapped holes 66; its lower end carries a frustoconical force introduction tip 72, which engages in one of the apertures 42 of the lattice 26 on the first pipe 22a and lies on the outer wall 24 of the first pipe 22a.
A positive connection element 74a is arranged between each force introduction tip 72 and the next lattice node in the direction of the second pipe 22b, referred to as 38a in FIGS. 4 and 5; the tip 72 and two lattice braces 40a adjacent the node 38a lie flat against the element 74a, thereby preventing any movement of the tip 72 and node 38a towards each other.
The positive connection element 74a comprises a filling material which has been hardened in the gap between the force introduction tip 72 and the lattice node 38a, for example a thickened resin or cement or a low boiling point metal alloy.
To allow insertion of filling material in the said gap, the fixing pin 70 contains a radial filling passage 76, which passes through it in a radial direction and opens into a recess 75 in the flange element 50 outside the pin 70, and a central axial filling passage 78 connecting the top 80 of the pin 70 to the radial passage 76.
The recess 75 in the flange element 50 forms a connection between one end of the radial filling passage 76 and the interior of the element 50, while the end of the radial filling passage 76 remote from the recess 75 is closed by the flange element, so that no filling material can exit there.
Like the first flange element 50 the second flange element 52 has tapped holes 81 and recesses 83 arranged equidistant from each other along its circumference and passing through the second element in a radial direction. A fixing pin 70, identical with the fixing pin 70 in the tapped holes 66 of the first flange element 50, is screwed into each of the tapped holes 81 of the second flange element 52; its tapering force introduction tip 72 engages in an aperture 42 in the lattice 26 of the second pipe 22b of the pipe connection 48, with its underside lying on the outer wall 24 of the second pipe 22b.
A positive connection element 74b is arranged between each force introduction tip 72 and the next lattice node 38b in the direction of the first pipe 22a; the tip 72 and lattice braces 40b adjacent the node 38b lie flat against the element 74b, thereby preventing any movement of the tip 72 and node 38b towards each other.
Like the positive connection element 74a the positive connection element 74b is formed by injecting a paste-like or liquid, quick-setting filling material through an axial filling passage 78 and a radial filling passage 76 in the relevant fixing pin 70 and the respective recess 83 into the gap between the force introduction tip 72 and the lattice node 38b, and allowing it to set there.
As will be seen from FIG. 1, the first flange element 50 and second flange element 52 also contain the same axial holes 82 and 84 respectively, extending right through them; the holes are arranged equidistant from each other along the circumference of the flange elements 50 and 52, in each case between two radial tapped holes 66 and 81, an axial hole 82 in the first flange element 50 in each case being aligned with an axial hole 84 in the second flange element 52.
Each pair of axial holes 82 and 84 has a clamping screw 86 passing through them; the head 88 of the screw lies on a first washer 90, which in turn lies on the end of the second flange element 52 remote from the first flange element 50. A clamping nut 92 is screwed onto one end of the screw 86 carrying external thread and projecting from the axial hole 82 in the first flange element 50; it lies on a second washer 94, which in turn lies on the end of the first flange element 50 remote from the second flange element 52.
By tightening the clamping nuts 92 on the clamping screws 86 the two flange elements 50 and 52 and thus the lattice nodes 38a and 38b positively fixed thereto can be moved towards each other.
The lattices 26 of the two pipes 22a and 22b are also fastened at the ends of the pipes remote from the pipe connection 48, e.g. by a pipe connection 48' of similar structure to the connection 48 (see FIG. 1), so that the lattices 26 of the pipes 22 can undergo longitudinal expansion axially of the pipes 22 by tightening the nuts 92 on the screws 86.
By bracing the flange elements 50 and 52 against each other force can thus be introduced into the lattice 26 longitudinally of the pipes 22a, 22b.
Thus the flange elements 50 and 52 which can be braced against each other, together with the fixing pins 70 and the positive connection elements 74a, 74b, act as force introduction means for the lattices 26. The end portions of the pipes 22, in which the fixing pins 70 engage in apertures 42 in the lattices 26, form fixing areas in which the lattices 26 are fixed relative to the respective pipes 22.
Owing to the frustoconical shape of the force introduction tips 72 of the fixing pins 70, the pipes 22a, 22b can further have a compressive bias applied directly to them right to their end portions.
The lattices 26 can slide freely over the outer walls 24 of the pipes 22 between the pipe connections 48, 48'. Since the angle at which the lattice bars 30 and 36 of the first family 28 and second family 34 intersect can be changed relatively easily, longitudinal expansion of the lattices 26 is effected primarily by shear deformation and longitudinal expansion of the lattice bars 30, 36 rather than by bending deformation of the lattice braces 40. This leads to a reduction of bending stresses at the lattice nodes 38, so that the lattices 26 are loaded substantially only in one dimension, namely in the longitudinal direction of the braces 40, and the full unidirectional strength of the fibre composites from which the lattice bars 30, 36 are made can thus be utilized in the direction of the fibres.
On shear deformation of the lattice bars 30, 36 to take up the longitudinal expansion of the lattices 26, the length of the first diagonals 44 of the lattice apertures 42 increases while the length of the second diagonals 46 decreases. The longitudinal expansion of the lattices 26 consequently leads to transverse contraction thereof, so that the lattices 26 shrink onto the associated pipes 22 and apply a compressive bias to the respective pipe 22 around the circumference.
If the interior of the piping 20 is filled with a fluid under an internal pressure, a tensile stress around the circumference is applied to each of the pipes 22 by virtue of the internal pressure and is in the opposite direction to the compressive bias resulting from transverse contraction of the relevant lattice 26. The tensile stress around the circumference, to be taken up by the material of the pipes 22 by virtue of the internal pressure, is thus reduced by the amount of bias introduced into the pipes 22 by means of the reinforcement (the lattices 26), so that the maximum internal pressure sustainable by the piping 20 increases correspondingly.
The compressive bias is ideally adjusted by tightening the clamping nuts 92, so that it is substantially equal to the tensile stress around the circumference based on the envisaged internal operating pressure (e.g. of 40 bars). This ensures that the pipes 22 are virtually stress-free in the operative state.
Since the friction between the lattice bars 30, 36 and the outer wall 24 of the pipes 22 may reduce the compressive bias produced by longitudinal expansion of the lattices 26 in the central portion of each pipe 22, it is beneficial when mounting the piping 20 first to pre-expand the lattices 26 so that a compressive bias going beyond the aforementioned ideal value is obtained in the marginal portions of the pipes 22. The pre-expansion of the lattices 26 is then reduced sufficiently to obtain a uniform compressive bias with the aforementioned ideal value along the pipes 22.
Alternatively, or in addition to raising the compressive bias beyond the ideal value when assembling the piping 20, provision may be made for reducing friction between the bars 30, 36 and the outer walls 24 of the pipes 22 by the use of lubricants such as creep oils, in order to avoid undesirable reduction of the compressive bias.
Another advantage of the piping 20 according to the invention is that the lattices 26 reduce the tensile stress in an axial direction which has to be taken up by the pipes 22 owing to the internal pressure.
Finally, the piping 20 according to the invention is also more resistant to damage from the outside, caused e.g. by impact with a foreign body, than conventional pipings.
On the one hand the biassed pipes 22 only show cracking on a stronger impulse from a foreign body striking the piping 20 than do conventional pipings; on the other hand any cracking which may occur is not catastrophic, as it is with conventional pipings with pipes of brittle material, e.g. glass; owing to the reinforcement only small cracks form, through which the fluid contained in the piping 20 only escapes in small quantities and through which the internal pressure only drops gradually, so that in the event of damage there is sufficient time to take damage limitation measures. | In order to improve a piping comprising at least one pipe and reinforcement on the outer wall of each pipe in such a way as to increase the maximum permissible internal operating pressure, it is proposed that the reinforcement should be capable of expansion along the length of the pipe and capable of contracting radially in such a way that a bias pressure can be applied to the pipe around its circumference by the longitudinal expansion of the reinforcement. | 8 |
The present invention relates generally to synthetic turf for landscaping and athletic fields, and more particularly to synthetic turf having a cooling layer to substantially dissipate heat buildup common with synthetic turf.
Traditionally, athletic fields, as well as landscaped areas for homes and businesses, are covered with a natural grass covering. The natural grass is advantageous for cushioning and ability to quickly recover from abuse from weather, people or both.
In recent years, however, many athletic fields have been converted from natural grass to synthetic turf coverings. The reasons for converting to synthetic turf is most often linked to the high costs and time related to maintaining natural grass. Further, natural grass may have problems growing in certain environmental and man-made conditions, such as for example, desert regions, spaces shaded by buildings, domed fields and high traffic areas. In areas where the natural grass cannot grow properly or adequately, injuries can result from inadequate footing. In addition, poorly growing natural grass is typically not aesthetically pleasing.
Synthetic turf coverings have improved over the years to appear more like natural grass coverings. Other improvements have been made to give more cushioning and elasticity to the synthetic turf to make it more equal to the advantages of natural grass turf.
However, a primary disadvantage of synthetic turf coverings still exists. In particular, most synthetic turf coverings are comprised primarily of plastics, such as, for example, polyethylene. Such plastics absorb, retain and give off heat that can increase the temperature on a field to a potentially fatal level. Even the American Academy of Pediatrics has identified infill artificial turf as contributing to elevating a person's core body temperature, thereby leading to heat related injuries such as, for example, heat cramps, heat exhaustion and heat stroke.
It has been found that naked synthetic turf coverings, that is, synthetic tuft coverings without infill material, such as, for example, sand and rubber, can reach temperatures of 140° F. or greater. Natural grass coverings measure about 85° F. under similar circumstances. Essentially, the materials comprising most synthetic turf coverings absorb heat from the sun and retain the heat to a much greater extent than natural grass coverings. Sand and rubber granules have been used as infill to increase footing and playability of athletic fields, but such infill materials do not mitigate heating issues of infill artificial tuft. In fact, rubber infill may actually contribute to increasing the temperature of the artificial turf. Lighter colored rubber granules and wetting the sand infill have been proposed as a mean by which to try and decrease the overall temperature of the synthetic turf covering, however, such proposals tend to cool the artificial turf for a very limited time and only at an almost insignificant temperature change.
In addition to being related to increasing heat-related injuries, synthetic turf coverings also are associated with heat pollution. The massive amount of heat rising from urban areas is increasingly being linked to both a delay and stimulation of precipitation. Some areas are experiencing a noticeable decrease in much needed rain and snow, while other areas are seeing an increase. There is strong support that heat and pollution from urban areas effects climate in an alarming way; primarily by redistributing water in an undesired fashion.
As such, governments are considering and implementing environmental standards to limit the heat generated from urban areas. Some of the standards call for increased natural green spaces and fewer areas of blacktop and concrete, that is, artificial spaces that buildup and give off great amounts of heat pollution. Typical synthetic turf coverings can behave very much like blacktop when it comes to heat pollution.
Attempts have been made to decrease the temperature of synthetic turf coverings. Attempts to cool synthetic tuft coverings include watering down the coverings. However the water quickly evaporates. More recent attempts include mechanical means in which a series of cooling pipes are constructed under the synthetic turf coverings. However, such mechanical means is expensive and would require removing currently laid synthetic turf coverings.
Ceramic beads having about 50% porosity have been combined with sand and rubber granules to supplement mechanical cooling systems as a means for cooling artificial turf coverings. However, the ceramic beads are unable to hold enough water to significantly decrease the temperature of the synthetic turf covering. Lighter colored rubber has also been proposed as a means for decreasing the temperature of the synthetic turf covering, but also does not lend to significantly decreasing the overall temperature of the synthetic turf covering.
Thus, what is needed is an economically affordable means for cooling both new and established synthetic turf coverings over a significant period of time and is environmentally friendly.
SUMMARY
The various exemplary embodiments of the present invention include a synthetic turf covering comprising a foundation, a plurality of grass-like pile filaments and a particulate infill. The foundation has a topside and a bottom side and the plurality of grass-like filaments are attached to the foundation and extend substantially upward from the topside of the foundation. The particulate infill comprises a super absorbent material.
The various exemplary embodiments of the present invention further includes a method of cooling a synthetic turf covering comprising introducing a particulate infill between grass-like filaments of the synthetic turf covering. The particulate infill comprises a super absorbent material. Liquid is then applied such that the super absorbent material increases density about 200 to about 400 times.
BRIEF DESCRIPTION OF DRAWING
Various exemplary embodiments of the present invention, which will become more apparent as the description proceeds, are described in the following detailed description in conjunction with the accompanying drawing, in which:
FIG. 1 is an illustrated representation of an exemplary embodiment of the present invention.
DETAILED DESCRIPTION
FIG. 1 is an illustration of an exemplary embodiment of a synthetic turf covering 10 of the present invention. As shown, the synthetic turf covering comprises a backing layer 20 resting upon a foundation layer 15 .
The foundation layer may be bare ground, gravel, sand, rubber or a combination thereof with stone or other similar materials in order to provide support and adequate drainage for the synthetic turf covering.
The foundation layer may be slightly angled towards strategically placed drain pipes to better and faster drying of the synthetic turf covering's top surface after rain or melted snow.
The backing layer may comprise of any known woven or unwoven fabric to which grass-like filaments 30 may be attached. Examples of conventional backing layers include woven warp type strands and cross or woof type strands to produce a woven sheet. The woven sheet may be coated with a rubber-type coating on a topside 24 , a bottom side 22 or both. It is preferred that the backing layer comprise of a stable, weather resistant material such as polypropylene, nylon, or similar material.
The backing layer is preferably supple and flexible such that it may conform to the foundation layer and potentially give when impacted.
Grass-like filaments 30 are attached to the backing layer such that the grass-like filaments extend upward, away from the foundation layer and backing layer. The grass-like filaments may be groups of filaments individually attached to the backing layer or thick individual filaments that are split at the top to give the appearance of numerous individual fibers.
The grass-like filaments may vary in thickness and size to give an appearance of natural grass. Typically, the grass-like filaments are comprised of polypropylene or the like.
Any known foundation layer, backing layer and grass-like filaments may be used in the various exemplary embodiments of the present invention.
A particulate infill 40 is introduced once the backing layer with attached grass-like filaments is laid over the foundation layer. The particulate infill is applied to any desired depth. In a preferable exemplary embodiment, the particulate infill comprises greater than about 10% of an average height of the grass-like filaments to about 90% of the average height of the grass-like filaments. In another preferable exemplary embodiment, the particulate infill comprises greater than about 25% of an average height of the grass-like filaments to about 75% of the average height of the grass-like filaments
The particulate infill comprises one or more hydrophilic materials, such as, for example, one or more super absorbent polymers such as, for example, polyacrylamide or polyacrylate. Preferably the hydrophilic material swells in water or other introduced liquids to about 200 to about 400 times its density. It is also preferred that the hydrophilic material is nontoxic and biodegradable.
When the super absorbent polymers are contacted with water, the super absorbent polymers increase dramatically in size. Depending on the granule size, the super absorbent polymers may reach maximum moisture retention in as quickly as about ten minutes. After reaching maximum moisture retention the retained moisture slowly releases from the super absorbent polymers depending on the particular conditions present, such as, for example, ambient temperature, sunlight, humidity, etc. Typically, the moisture evaporates from the super absorbent polymers and thereby keeps the backing layer and grass-like filaments cool.
Super absorbent polymers are available as various sizes of granules, and any size granule may be comprised in the particulate infill. The larger the granule, the slower it degrades. However, the smaller the granule, the faster it hydrates.
In a preferred exemplary embodiment, the super absorbent polymers have a granule size of about 2 mm to about 4 mm.
The life of the super absorbent polymers depends on various conditions, including, for example, adjacent soil conditions, microbes that feed on the super absorbent polymers, foot traffic, weather conditions and the like. Some super absorbent polymers may have a life of several years and have an estimated cost of less than about one third of a comparative amount of rubber granules.
The particulate infill may further comprise sand, rubber granules, ceramic beads, soil and combinations thereof.
It in various exemplary embodiments of the present invention, when combining super absorbent polymers with sand, rubber granules, ceramic beads, soil or combinations thereof, the particulate infill is substantially homogeneous. That is, for example, it is preferred in various exemplary embodiments that the particulate infill not be divided into various layers of materials.
The particulate infill materials, in conjunction with the grass-like filaments attached to the backing layer, tend to mutually stabilize and hold one another in predetermined position. However, as the super absorbent polymers change size depending on moisture conditions, there is some shifting of the particulate infill materials.
When the super absorbent polymers are at a maximum moisture retention, the super absorbent polymers are more flexible and absorb imparted impacts more effectively, thereby potentially reducing injuries to individuals hitting the synthetic turf covering. The overall desired flexibility of impact absorption and playing characteristics desired by a synthetic turf covering may be manipulated by varying the percentage of super absorbent polymers in the particulate infill.
Maintenance of particulate infill of the various exemplary embodiments of the present invention is very low. Depending on the size of super absorbent polymer comprising the particulate infill, the particulate infill is replenished annually or every several years as the super absorbent polymer degrades.
When combining soil in the particulate infill, natural grass may be grown within and through the synthetic turf covering. The natural grass may provide a more realistic appearance to the synthetic turf covering.
The particulate infill of the exemplary embodiments of the present invention may be applied to any new or existing synthetic turf coverings. The synthetic turf covering may further comprise an underground sprinkler system for applying water to the super absorbent polymers as needed.
While this invention has been described in conjunction with the specific embodiments outlined above, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, the preferred embodiments of the invention as set forth above are intended to be illustrative, not limiting. Various changes may be made without departing from the spirit and scope of the invention. | The present invention describes a synthetic turf having super absorbent materials in order to keep the synthetic turf cooler than conventional synthetic turfs. | 4 |
[0001] This application is a continuation application of co-pending U.S. patent application Ser. No. 10/177,715, filed Jun. 20, 2002, which is a continuation of co-pending U.S. patent application Ser. No. 09/213,199, filed Dec. 17, 1998, now issued as U.S. Pat. No. 6,434,574.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates generally to computer operating systems and more particularly to storing and retrieving filenames in computer memory.
[0004] 2. Description of the Background Art
[0005] The storing and retrieving of filenames in computer memory is extremely important to all computer users. When a computer user saves a file and filename into computer memory, it is important that the filename remain uniquely identifiable regardless of any other filenames or text encodings saved in the memory. If a filename is not uniquely identifiable, then a computer may be unable to retrieve the named file. Further, if the memory containing the filename is moved to a different computer then that filename must remain identifiable if the named file is to be retrievable.
[0006] Conventionally, a filename identity is represented by a string of bytes (“encoding”) stored in computer memory. A conventional Roman character based computer system will interpret the encoding to represent Roman characters in the American Standard Code for Information Interchange (ASCII) character set, even if the encoding actually represents Japanese characters. For example, a Japanese computer user may save a file with a Japanese filename onto a removable memory device, such as a floppy disk. The Japanese filename encoding is interpreted by a conventional Japanese character based computer system to be Japanese characters. However, if the Japanese user then inserts the removable memory device into a conventional Roman character based computer system, the Roman computer system will assume the Japanese encoding actually represents a Roman character filename rather than a Japanese character filename.
[0007] A problem with the conventional Roman character based computer system is that because it assumes that a filename is in Roman characters, it may equate two non-Roman character filenames as being identical. This is because a Roman computer system treats uppercase and lowercase letters in a filename as equivalent. Therefore, a Roman computer system would assume that the filenames “Example.txt” and “example.txt” (and their associated files) are the same even though they are represented by different strings of bytes, possibly leading to the assumption that two non-Roman filenames, which vary only by case, are identical. If a Roman computer system misinterprets a non-Roman filename, the system may mistakenly open the wrong file or may refuse to create a new file since it believes that that filename is already in use.
[0008] FIG. 1 is a diagram of Japanese characters in which characters within any given column appear identical to a conventional Roman character based computer system. For example, characters 104 , 106 , 108 and 110 in column 102 appear identical to a prior art Roman computer system because it treats all filenames as if they were written in the Roman alphabet. Therefore, if two Japanese filenames differed by just one character, such as characters 104 and 106 , a prior art Roman computer system would actually consider them to be identical. Similar problems occur with other text encodings but the problem is most acute in Japanese and Chinese text encodings since in these languages each character is a word and therefore filenames are shorter and more likely to vary by just one character.
[0009] A Roman character based prior art system can only store filenames in Roman text encodings as partially represented by ASCII text encoding table 200 of FIG. 2 . Each Roman character has its own encoding. For instance, character 202 , the letter “A”, is stored as 7-bit encoding 204 . However, because ASCII only allows 7 bit encodings, which means that ASCII can encode only 128 characters, basic ASCII encoding table 200 contains no encodings for Japanese or any other language that uses non-Roman characters. Japanese and other east-asian languages can easily have several thousand characters that need to be encoded. Therefore, a prior art Roman character based computer system cannot always accurately store or retrieve some east-asian filenames or other non-Roman filenames.
[0010] Therefore, an improved system and method are needed to store and retrieve filenames and files in a computer system.
SUMMARY OF THE INVENTION
[0011] The present invention provides a system and method for accurately storing and retrieving filenames in computer memory by converting filenames into Unicode text encoding. The Unicode Standard, like the ASCII text encoding standard and others, encodes each character as a numerical value. However, instead of encoding simply in ASCII, Unicode text encoding encodes all the characters used in the world's major written languages, including Greek, Arabic, Tamil, Thai, Japanese, Korean and many others.
[0012] The invention stores a filename into computer memory by first determining a default text encoding based upon which it converts the filename into Unicode text encoding. If the conversion is successful, the invention stores the Unicode text-encoded filename into computer memory and sets a bit that corresponds to the default text encoding in an Encoding Bitmap located in computer memory.
[0013] If the conversion based on the default text encoding is unsuccessful, the invention tries using Roman text encoding to convert the filename into Unicode text encoding. Once the conversion is complete, the invention stores the filename into computer memory and sets the bit that corresponds to Roman text encoding in the encoding bitmap. The invention assumes that any sequence of bytes can be converted to Unicode using Roman text encoding, which assigns a meaning to every possible byte sequence. If conversion using the default encoding fails, conversion using Roman text encoding will definitely succeed, even if it produces the wrong Unicode characters.
[0014] To retrieve a filename, the invention first converts the retrieval request into Unicode text encoding based on the default text encoding of the system. The invention then searches the computer memory for a matching Unicode text encoded filename. If the search is successful, the search result is returned. If the search is not successful, the invention determines if Roman text encoding is the default text encoding. If Roman text encoding is not the default text encoding, the invention uses Roman text encoding to convert the retrieval request into Unicode text encoding and then searches the computer memory for a matching Unicode filename. If the search is successful, a search result is returned.
[0015] If the search is not successful, or if Roman text encoding is the default text encoding, the invention next retrieves a list of all text encodings previously used in the system as specified in an Encoding Bitmap located in the computer memory of the system. The invention then converts the retrieval request into Unicode text encoding based on each text encoding specified in the encoding bitmap and uses each conversion to search the computer memory for a match. If a match is found, the invention returns the search result.
[0016] Finally, if the search is still not successful the invention converts the retrieval request into Unicode text encoding based on any other text encodings installed in the computer memory that have yet to be tried. The invention then uses each conversion in searching the computer memory for a matching Unicode filename. If the search is successful, the invention returns the search result. If the search is not successful, the invention returns an error message.
[0017] Accordingly, the present invention not only more accurately and efficiently stores and retrieves filenames in computer memory but also allows multiple encodings to be used in computer memory over time.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 is a diagram of Japanese characters in columns that appear identical when storing or retrieving a filename using a prior art system;
[0019] FIG. 2 is a diagram of ASCII text encodings used by a prior art system;
[0020] FIG. 3 is a block diagram of a computer system suitable for use with the present invention;
[0021] FIG. 4 is a block diagram of the preferred allocation of the memory shown in FIG. 3 ;
[0022] FIG. 5 is a block diagram of the preferred embodiment of the Unicode Table in the memory shown in FIG. 4 ;
[0023] FIG. 6 is a block diagram of the preferred embodiment of the Encoding Bitmap in the memory shown in FIG. 4 ;
[0024] FIG. 7 is a flowchart of preferred method steps for storing a filename into computer memory according to the present invention; and
[0025] FIGS. 8 a and 8 b are a flowchart of preferred method steps for retrieving a filename from computer memory according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0026] The present invention relates to an improvement in storing filenames in, and retrieving them from, computer memory.
[0027] FIG. 3 is a block diagram of a computer system suitable for use with the invention. Computer system 300 preferably includes a Central Processing Unit (CPU) 304 , a monitor 306 , a keyboard 308 , memory 310 , and an input and output (I/O) interface 312 , all connected by a system bus 302 . Memory 310 may comprise a hard disk drive, random access memory (RAM) or any other appropriate memory configuration.
[0028] FIG. 4 is a block diagram of the preferred allocation of memory 310 , which stores a Unicode table 402 that contains 16 bit encodings for most modern written languages as discussed further in conjunction with FIG. 5 . Memory 310 also stores a File Manager 404 which manages document 406 and other documents with their respective filenames that are stored in memory 310 , as discussed further in conjunction with FIG. 7 , FIG. 8 a and FIG. 8 b . Memory 310 also stores text encodings 408 for various languages such as Roman, Greek and Japanese, and an encoding bitmap 410 which lists all previously used text encodings, as discussed further in conjunction with FIG. 6 .
[0029] FIG. 5 is a diagram of the preferred embodiment of the Unicode Table 402 , which contains bit encodings for most of the world's modern written languages. Unicode, published as The Unicode Standard, Worldwide Character Encoding, is now the standard for representing text. Unicode uses a 16-bit coding scheme that allows for 65,536 distinct characters—more than enough to include all languages in use today. Currently, Unicode text encoding covers 38 , 887 different characters. For example, the Roman character “A” 502 is represented by bit encoding 504 . The Greek character “α” 506 is represented by bit encoding 508 . The Chinese character for sky (“tian” in Mandarin Chinese and “tin” in Cantonese) 510 is represented by bit encoding 512 . Most modern written languages can be encoded using Unicode text encoding. However, some relatively obscure languages in current use, such as Cherokee and Mongolian, cannot be encoded using Unicode text encoding. Accordingly, almost any filename can be accurately represented in its native language using Unicode text encoding instead of having to be converted, possibly inaccurately, to Roman characters.
[0030] FIG. 6 is a diagram of the preferred embodiment of the FIG. 4 Encoding Bitmap 410 , which contains a list of all text encodings previously used in system 300 . Whenever a given text encoding is used in system 300 , file manager 404 sets a relevant field in encoding bitmap 410 . For instance, if field 602 represents Hebrew and Hebrew has not been used in system 300 , field 602 contains a 0. If field 604 represents Arabic and Arabic has been used in system 300 , field 604 contains a 1.
[0031] FIG. 7 is a flowchart of steps in a preferred method 700 for file manager 404 to store a filename into computer memory 310 according to the Invention. In step 703 , file manager 404 receives a “save” request, which contains filename information for document 406 . Alternatively, the “save” request can be a request to change a filename. In step 704 , file manager 404 creates a file and/or saves document 406 in memory 310 . If the save request in step 703 was a change filename request, step 704 can be skipped. The contents of the document 406 can also be saved in memory 310 after completion of the method 700 .
[0032] In step 706 , file manager 404 determines a default text encoding of system 300 , which in this case is a text encoding used to view filenames on monitor 306 . In step 708 , file manager 404 uses the default text encoding determined in step 706 to convert the filename to a Unicode name.
[0033] Step 710 determines whether the step 708 conversion using the default text encoding was successful. If the step 708 conversion was not successful, then in step 712 file manager 404 uses Roman text encoding to convert the user-entered filename to Unicode text encoding. Note that step 712 cannot fail. Even if the filename was not actually written in Roman characters, method 700 will still convert the user-entered filename to Unicode using Roman encoding. This is because all possible byte sequences yield valid Roman characters that can be converted into Unicode. The filename will not be in the intended characters, but the filename will be individually distinguishable.
[0034] Once the step 712 conversion is complete, or if the step 708 conversion was successful, then in step 714 file manager 404 saves the Unicode name to memory 310 . In step 716 , Me manager 404 sets a bit in encoding bitmap 410 that corresponds to the type of text encoding used to convert the user-entered filename. In step 718 method 700 ends.
[0035] FIGS. 8 a and 8 b are a flowchart of steps in a preferred method 800 for file manager 404 to retrieve a filename from computer memory according to the invention. In step 804 file manager 404 receives a search request which was generated when a system 300 user attempted to open document 406 , or any other document, stored in memory 310 . The search request contains a user-entered filename. In step 805 file manager 404 converts the user-entered filename to Unicode text encoding based on the default text encoding of system 300 . As discussed in conjunction with FIG. 7 , the default text encoding in this example is the text encoding used to view filenames on monitor 306 . If the step 805 conversion was not successful, then file manager 404 proceeds to step 816 as discussed below. If the conversion was successful, then in step 807 file manager 404 searches memory 310 for the converted filename. If file manager 404 locates a matching filename, file manager 404 returns the search result and retrieves the file having the matching filename in step 812 and method 800 ends in step 814 .
[0036] If the step 807 search did not locate a matching filename, or if the step 805 conversion was not successful, then in step 816 file manager 404 determines if Roman text encoding is the default text encoding of system 300 . If Roman text encoding is not the default text encoding, then in step 817 file manager 404 converts the user-entered filename to Unicode text encoding using Roman text encoding. In step 819 , file manager 404 searches memory 310 for the converted filename. If it finds a matching filename, then in step 822 file manager 404 returns a search result and retrieves the file having the matching filename, and method 800 ends in step 824 .
[0037] If the step 819 search did not locate a matching filename, or if in step 816 file manager 404 determined that Roman text encoding is the default text encoding of system 300 , then in step 826 file manager 404 retrieves a list of text encodings from encoding bitmap 410 .
[0038] Next, in step 827 , file manager 404 converts the user-entered filename into Unicode text encoding using a text encoding from the list retrieved in step 826 from encoding bitmap 410 . File manager 404 converts the filename into Unicode using only text encodings not already used in steps 805 and 817 . However, in practice system 300 will probably only have installed one or two 1 text encodings—usually Roman and a local text encoding such as Japanese. The local text encoding is normally set as the default text encoding that is tried in step 805 . Therefore, method 800 generally is successful at either step 808 or step 820 and does not reach step 826 .
[0039] If the step 827 conversion is not successful, then File Manager 404 proceeds to step 834 . If the step 827 conversion is successful, then in step 829 file manager 404 uses the converted user-entered filename to search memory 310 for a matching Unicode filename. If in step 830 the search is successful, then in step 832 file manager 404 returns a search result and retrieves the file having the matching filename, and in step 833 method 800 ends. If in step 830 the search was unsuccessful, or if the step 827 conversion was unsuccessful, then in step 834 file manager 404 determines if there are other text encodings listed in encoding bitmap 410 that have not been tried. If there are some text encodings that have not yet been tried, then file manager 404 returns to step 827 .
[0040] If in step 834 all text encodings listed in encoding bitmap 410 have been tried, then file manager 404 proceeds to step 835 and tries to convert the user-entered filename into Unicode text encoding based on any other text encodings installed in system 300 . As in step 827 , file manager 404 tries conversions to Unicode text encoding using only previously untried text encodings. If the step 835 conversion Is unsuccessful, then File Manager 404 proceeds to step 844 . Otherwise, in step 837 , file manager 404 searches memory 310 for a matching Unicode filename. If the search is successful, then in step 840 file manager 404 returns a search result and retrieves the file having the matching filename, and in step 842 method 800 ends. If the search is unsuccessful, but in step 844 not all text encodings have been tried, then file manager 404 returns to step 835 and tries to convert the user-entered filename to Unicode text encoding using another text encoding. If in step 844 all the text encodings installed in system 300 have been tried, then in step 846 file manager 404 returns an error result and in step 848 the method 800 halts.
[0041] The invention has been explained with reference to a preferred embodiment. Other embodiments will be apparent to those skilled in the art in light of this disclosure. For example, the invention may readily be implemented using configurations other than those described in the preferred embodiment. Additionally, the invention may effectively be used in conjunction with systems other than the one described as the preferred embodiment. Therefore, these and other variations upon the preferred embodiments are intended to be covered by the appended claims. | The invention receives a request to store a file having a filename written in a first text encoding, converts the filename into a Unicode filename and stores the Unicode filename and the file into memory. The invention then sets a flag, associated with the memory, indicating that a first text encoding has been used. To retrieve a Unicode filename, the invention receives a request to locate a Unicode filename from memory. Next, the invention uses a predetermined text encoding to convert the filename into Unicode. The invention then searches for the Unicode filename in the memory. If the Unicode filename is not found, the invention uses a next text encoding from the set of text encodings which have been used, to repeat the conversion and searches the memory until the Unicode filename is identified. Lastly, the Unicode file is retrieved. | 8 |
PRIORITY/CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the priority date of the provisional application entitled HORSE HALTER filed by Byron Grant on Sep. 19, 2008 with application Ser. No. 61/098,272, the disclosure of which is incorporated by reference.
FIELD OF THE INVENTION
[0002] The invention generally relates to an apparatus for haltering horses, and more particularly to halters made of webbing or leather straps.
BACKGROUND OF THE INVENTION
[0003] Halters for horses are common in the art and have been for well over a century. Various halter types have been made over those years to address the needs of training, leading and tying horses. Common features of the halters found in the prior art include a nose band that encircles the nose of the horse and some sort of a poll strap or crown strap that fits over the back of the horse's head behind the ears. The problem with common halter designs is the strength of the halter is compromised due to the numerous fittings included in the halter to allow it to be mounted on or fit on the horse and removed from the horse.
[0004] The art includes examples of halters that are designed to break away easily if the horse becomes entangled in a feature in the environment or potentially entangled with its own feet. An example of this is U.S. Pat. No. 3,605,384 to Pacini titled Breakaway Halter.
SUMMARY OF THE INVENTION
[0005] The present invention addresses this weakness in available halter designs by including a headstall strap permanently formed and fastened into a continuous loop that fits over the poll of the horse and includes a lead attachment ring at the bottom of the headstall strap. This strap and the connection made to form the continuous loop are made of materials of adequate strength to control the horse and prevent the halter from breaking when the horse pulls back or jerks against the halter. This saves the owner of the horse the expense of replacing broken halters and protects the horse from harm or injury that may result if the horse becomes untied and free to run unsupervised in an area of unknown hazards.
[0006] The purpose of the Abstract of the Disclosure is to enable the public, and especially the scientists, engineers, and practitioners in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection, the nature and essence of the technical disclosure of the application. The Abstract is neither intended to define the invention of the application, which is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way.
[0007] Still other features and advantages of the claimed invention will become readily apparent to those skilled in this art from the following detailed description describing preferred embodiments of the invention, simply by way of illustration of the best mode contemplated by carrying out my invention. As will be realized, the invention is capable of modification in various obvious respects all without departing from the invention. Accordingly, the drawings and description of the preferred embodiments are to be regarded as illustrative in nature, and not as restrictive in nature.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 shows one embodiment of a horse halter fitted on a horse.
[0009] FIG. 2 shows a second embodiment of a horse halter not fitted on a horse.
[0010] FIG. 3 shows a front view of the halter in FIG. 1 not fitted on a horse.
[0011] FIG. 4 shows a side view of the halter of FIG. 1 not fitted on a horse.
[0012] FIG. 5 shows a third embodiment of the horse halter fitted on a horse.
[0013] FIG. 6 shows a fourth embodiment of the horse halter fitted on a horse.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0014] While the invention is susceptible of various modifications and alternative constructions, certain illustrated embodiments thereof have been shown in the drawings and will be described below in detail. It should be understood, however, that there is no intention to limit the invention to the specific form disclosed, but, on the contrary, the invention is to cover all modifications, alternative constructions, and equivalents falling within the spirit and scope of the invention as defined in the claims.
[0015] In the following description and in the figures, like elements are identified with like reference numerals. The use of “e.g.,” “etc,” and “or” indicates non-exclusive alternatives without limitation unless otherwise noted. The use of “including” means “including, but not limited to,” unless otherwise noted.
[0016] Disclosed is a halter apparatus (“halter”) 10 for a horse. FIG. 1 shows the halter 10 placed on a horse 2 and illustrates the general features of the halter including the continuous headstall strap 20 , and a guide ring 26 that encompasses both sides of the headstall above the lead ring 28 . The continuous headstall strap 20 passes through the lead ring 28 . The continuous headstall strap is formed of leather, webbing or other suitable material and is formed into a continuous loop with a permanent, fixed high strength connection.
[0017] There is a brow band 30 which includes a headstall loop 32 fitted to slide on the headstall strap snug enough to retain its position unless it is moved by the owner and in a like manner a throat latch loop 34 that is also slidable on the throat latch strap 40 . The brow band is preferably symmetrical and includes a headstall loop 32 and a throat latch loop 34 on each side of the halter. The throat latch 40 includes a buckle 42 and a number of adjustment holes 44 to allow adjustment for a proper fit when the halter is placed on a horse.
[0018] A nose band 60 is nonadjustable and sized to fit the horse. The nose band is attached to the headstall strap 20 on each side with headstall loops 62 that have a snug sliding fit on the headstall strap 20 . The nose band position is adjusted by the hanger straps 50 , one hanger strap is attached to each side of the halter each hanger strap includes an upper strap 52 that is fixed to the headstall strap 20 and has a number of holes 58 therethrough to allow adjustment.
[0019] A lower strap 54 that is fixed to the nose band 60 , this attachment may be accomplished by sewing the lower strap to the nose band or alternatively it may be riveted or attachment may be made using a ring or a halter square of the three position type. The lower strap 54 has a buckle 56 attached at its top end to engage holes 58 in the upper strap 56 to allow nose band 60 position adjustment for a proper fit on the horse. This halter would typically be made of nylon webbing or strap in the alternative it may be made of leather or any other suitable material that will not chafe the horse. Material used to make the halter must possess adequate strength to control the horse without breaking or damaging the halter.
[0020] The halter 110 of FIG. 2 differs from FIG. 1 in that the headstall strap 120 is stitched together at 124 above the lead ring 128 instead of having a guide ring installed. Otherwise the halter 110 of FIG. 2 is identical to the halter shown in FIG. 1 and simply represents an alternative method of construction.
[0021] FIG. 3 shows the halter of FIG. 1 without the horse to more clearly illustrate the location of the parts of the halter. The location of the hanger straps on both sides of the halter are clearly shown at 50 and 50 ′ and it is shown that the various parts of the upper and lower straps 52 and 54 on the left side are mirrored by 52 ′ and 54 ′ on the right side of the halter. Buckles 56 and 56 ′ are shown on the left and right sides as they would fit to the left and right sides of the halter.
[0022] FIG. 4 shows a side view of the halter of FIG. 1 , without the horse, and illustrates the continuous nature of the headstall strap 20 and also provides a clear illustration of the throat latch loop or strap 40 .
[0023] FIG. 5 shows the preferred embodiment of the halter 210 fitted on a horse. The halter 210 includes a continuous headstall strap 220 , a lead ring 228 , a guide ring 230 that encircles both sides of the headstall strap and will slide easily over the headstall strap 220 but will not pass over the lead ring 228 . The continuous headstall strap is formed of leather, webbing or other suitable material and is formed into a continuous loop with a permanent, fixed, high strength connection.
[0024] Cheek rings 226 are attached to each side of the headstall strap near the top. A throat latch is made of three pieces: a left throat latch strap 242 , a right throat latch strap 244 , and a throat latch buckle 246 . The left throat latch strap 242 is attached to the left cheek ring and is provided with a number of adjustment holes 248 . The buckle 246 is fitted to one end of the right throat latch strap the end of the right throat latch strap 244 . The right throat latch strap end opposite buckle 246 is secured to the right cheek ring. In use the throat latch buckle 246 engages a hole 248 on the left throat latch strap 242 as selected the user.
[0025] The four piece nose band 260 includes a front nose band 262 , a rear nose band 264 , and two halter squares 266 , namely one halter square on each side of the halter. The second halter square is not visible in this Figure. Loops 268 are formed on each side of the rear nose band 264 and are sized to slide on the headstall strap 220 . The nose band position is regulated by hanger straps 250 located one on each side of the halter.
[0026] In this figure, hanger strap 250 on the left side of the halter is visible and the right hanger strap is not visible. Each hanger strap 250 is comprised of three parts: an upper hanger strap 252 , a lower hanger strap 254 , and a hanger strap buckle 256 . One end of the lower hanger strap 254 is fitted into the top position of the halter square 266 , however, as an alternative it could be sewed directly to the nose band if it was desirable to eliminate the halter square. Hanger strap buckle 256 is fitted to the end of the lower hanger strap 254 opposite the halter square and is preferably secured by stitching as is common in the art.
[0027] One upper hanger strap 252 is secured to each cheek ring 226 by stitching or other suitable connecting method. The upper hanger strap is fitted with a series of holes 258 . Hanger strap buckles 256 on each side of the halter engage holes 258 to support the nose band 260 at the desired position. It is understood that hanger strap 250 and its parts (the upper hanger strap 252 , lower hanger strap 254 , hanger strap buckle 256 , and the hanger strap adjustment holes 258 ) are mirrored on the right side of the halter. The halter of FIG. 5 is preferably manufactured from nylon webbing and metal rings however it may be manufactured without the rings, so that buckles are the only metal parts. Leather straps or any other materials that will not chafe the horse and that provide adequate strength may be substituted for nylon webbing. The great benefit of this halter is the strength of the headstall strap as it is formed into a continuous permanent loop without detachable connecting means such as buckles. As a result of this permanently formed continuous loop the headstall strap has adequate strength that a horse cannot pull back and break the halter, thereby solving a common problem with halters available in the market today.
[0028] FIG. 6 shows another embodiment of the halter 210 fitted on a horse. The halter of FIG. 6 differs from the halter of FIG. 5 having a fixed length hanger straps 250 . Only the left side of the halter is visible in FIG. 6 and the fixed length right hanger strap is not visible. The position of nose band 260 is not adjustable. The non-adjustable halter shown in FIG. 6 does not include a brow band.
[0029] While there is shown and described the present preferred embodiment of the invention, it is to be distinctly understood that this invention is not limited thereto but may be variously embodied to practice within the scope of the following claims. From the foregoing description, it will be apparent that various changes may be made without departing from the spirit and scope of the invention as defined by the following claims.
[0030] Examples of various embodiments within the spirit and scope of the invention include the option of making the halter with or without a brow band. Another example of an optional feature is the use of adjustable hanger straps or fixed hangers straps. | A halter having a continuous headstall strap that fits over the poll of the horse's head and includes a lead attachment ring at the bottom of the headstall strap. | 1 |
BACKGROUND OF THE INVENTION
[0001] This invention relates to enclosures for vehicles, and more particularly to an enclosure having an adhesive-backed fastener that is used in conjunction with conventional snaps for quickly and easily installing the enclosure on a vehicle.
[0002] Conventional enclosures, such as enclosures for golf carts, are attached to golf carts using a combination of hook and loop fasteners and/or snaps. Conventional snaps require an installer to drill holes into the structure of the golf cart in order to attach each snap to the golf cart with a screw. Tracks having C-shaped channels are also commonly used to attach an upper edge of a golf cart enclosure to a roof of a golf cart. A golf cart enclosure is attached to the track by sliding a cord sewn into the upper edge of the golf cart enclosure into the C-shaped channel. The tracks are attached to the roof using screws or nuts and bolts. This requires designing the brackets so screw holes on the brackets line up with existing screw holes on the roof Installation of the tracks is time consuming and costly because it often requires some dismantling of the roof and the roof support structure to gain access to existing screw holes to install the C-shaped channels (usually expensive aluminum). Furthermore, conventional installations wherein holes are drilled into any portion of a golf cart will void most golf cart manufacturers' warranties.
[0003] Therefore, a need exists for a vehicle enclosure and method of installation that will allow a user to quickly install and secure the enclosure to a vehicle without having to drill any holes into the vehicle or use brackets to attach the enclosure to the roof of a golf cart.
[0004] The relevant prior art includes the following references:
[0000]
Patent No.
Inventor
Issue/Publication Date
(U.S. Patent References)
D626,452
Helwig et al.
Nov. 02, 2010
D626,451
Helwig et al.
Nov. 02, 2010
7,560,003
Naughton et al.
Jul. 14, 2009
D557,191
Curtis, Jr. et al.
Dec. 11, 2007
7,213,864
Gasper
May 08, 2007
7,210,492
Gerrie et al.
May 01, 2007
6,979,044
Tyrer
Dec. 27, 2005
6,916,059
Feinberg
Jul. 12, 2005
RE38,272
Nation
Sep. 14, 2003
6,439,637
Tyrer
Aug. 27, 2002
6,132,089
Galomb et al.
Sep. 17, 2000
5,429,404
King, Sr.
Jul. 04, 1995
5,014,400
Ban
May 14, 1991
4,654,934
Hasegawa
Apr. 07, 1987
3,851,357
Ribich et al.
Dec. 03, 1974
3,784,235
Kessler et al.
Jan. 08, 1974
3,709,553
Churchill et al.
Jan. 09, 1973
1,242,108
Buob, Sr.
Sep. 02, 1917
(Foreign Patent, References)
EP2263491
Hayashi
Dec. 22, 2010
SUMMARY OF THE INVENTION
[0005] The primary object of the present invention is to provide a vehicle enclosure and method of installation that will allow a user to quickly install and secure the enclosure to a vehicle without having to drill any holes into the vehicle.
[0006] Another object of the present invention is to provide a vehicle enclosure and method of installation that will allow a user to quickly install and secure the enclosure to a vehicle without having to use brackets to attach the enclosure to the roof of the vehicle.
[0007] The present invention fulfills the above and other objects by providing an enclosure and method of installation comprising an enclosure having a plurality of adhesive-backed attachment devices, each having a stud or a socket that engages a conventional stud or a conventional socket of a conventional snap. The adhesive-backed attachment devices are preferably flexible so that the adhesive-backed attachment devices may be attached to uneven surfaces of a vehicle, such as rounded fenders or curved roofs of a golf cart. The adhesive-backed attachment devices eliminate unsightly brackets and decreases installation time of the enclosure. For example, an installer installing an enclosure having conventional studs and/or conventional sockets secured to the outer perimeter of the enclosure can attach adhesive-backed attachment devices to each conventional snap and conventional stud. Then, the installer can simply peel a protective layer off a rear surface of each adhesive-backed attachment device, thereby exposing an adhesive layer, and attach one-by-one each adhesive-backed attachment device to a vehicle, such as a golf cart. The installer can start on one corner of an upper edge of the enclosure and simply move along the upper edge peeling and sticking each adhesive-backed attachment device to the appropriate spot of the roof of the golf cart and then to the body of the golf cart. The studs and sockets may also be integrated into the vehicle, such as a new golf cart or into a new roof for retrofitting an existing golf cart.
[0008] The above and other objects, features and advantages of the present invention should become even more readily apparent to those skilled in the art upon a reading of the following detailed description in conjunction with the drawings wherein there is shown and described illustrative embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] In the following detailed description, reference will be made to the attached drawings in which:
[0010] FIG. 1 is a top perspective view of an adhesive-backed attachment device of the present invention having a socket as an engagement means;
[0011] FIG. 2 is a top perspective view of an adhesive-backed attachment device of the present invention having a stud as an engagement means;
[0012] FIG. 3 is a top perspective view of a conventional stud of a conventional snap;
[0013] FIG. 4 is a top perspective view of a conventional socket from a conventional snap;
[0014] FIG. 5 is a side view of a vehicle enclosure of the present invention attached to a golf cart using adhesive-backed attachment devices;
[0015] FIG. 6 is a partial cross-section view along line 6 - 6 of FIG. 5 of a vehicle enclosure of the present invention secured to a golf cart roof;
[0016] FIG. 7 is a cutaway side view of a vehicle enclosure of the present invention attached to a curved surface using a conventional socket and a flexible adhesive-backed attachment device;
[0017] FIG. 8 is a bottom view of an inner surface of a golf cart roof having adhesive-backed attachment devices integrated therein;
[0018] FIG. 9 is a flow chart illustrating a method of installation of a vehicle enclosure of the present invention on a roof of a golf cart; and
[0019] FIG. 10 is a flow chart illustrating a method of installation of a vehicle enclosure of the present invention on a body of a golf cart.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0020] For purposes of describing the preferred embodiment, the terminology used in reference to the numbered accessories in the drawings is as follows:
[0000]
1.
adhesive-backed attachment device
2.
socket
3.
engagement means
4.
base
5.
rear surface
6.
front surface
7.
conventional stud
8.
conventional snap
9.
securing means
10.
adhesive
11.
peel away cover
12.
stud
13.
conventional socket
14.
vehicle enclosure
15.
golf cart
16.
upper edge
17.
inner surface
18.
roof
19.
side edge
20.
outer surface
21.
body
22.
attachment means
23.
zipper
24.
sleeve
25.
curved surface
26.
side edge
27.
rear edge
28.
attaching conventional snap to enclosure
29.
attaching enclosure attachment device to conventional snap
30.
cleaning surface
31.
securing the enclosure attachment device to surface
32.
repeating previous step
33.
attaching remaining portions of enclosure
34.
attaching conventional snap to enclosure
35.
attaching upper edge to roof
36.
attaching enclosure attachment device to conventional snap
37.
cleaning surface
38.
securing the enclosure attachment device to surface
39.
repeating previous step
40.
attaching remaining portions ofen closure
[0021] With reference to FIG. 1 , a top perspective view of an adhesive-backed attachment device 1 of the present invention having a socket 2 as an engagement means 3 is illustrated. The adhesive-backed attachment device 1 comprises a base 4 having a rear surface 5 and a front surface 6 . The socket 2 extends upward from a central location of the front surface 6 of the adhesive-backed attachment device 1 . The socket 2 is attachable to a conventional stud 7 of a conventional snap 8 , as illustrated in FIG. 3 . A securing means 9 , such as adhesive 10 , is located on the rear surface 5 of the base 4 to allow a user to secure the adhesive-backed attachment device 1 to a surface, such as a golf cart. The adhesive 10 is preferably covered by a peel away cover 11 . The expanded surface area provided by the larger size of the base 4 provides additional contact area between the base 4 and a surface that the adhesive-backed attachment device 1 is being secured to. The adhesive-backed attachment device 1 may be made of a rigid material, such as plastic, metal and so forth, or of a flexible material, such as rubber, silicone and so forth, to allow a user to attach the adhesive-backed attachment device 1 to a curved surface, as illustrated in FIG. 7 .
[0022] With reference to FIG. 2 , a top perspective view of an adhesive-backed attachment device 1 of the present invention having a stud 12 as an engagement means 3 is illustrated. The adhesive-backed attachment device 1 comprises a base 4 having a rear surface 5 and a front surface 6 . The stud 12 extends upward from a central location of the front surface 6 of the adhesive-backed attachment device 1 . The stud 13 is attachable to a conventional socket 13 of a conventional snap 9 , as illustrated in FIG. 4 . A securing means 9 , such as adhesive 10 , is located on the rear surface 5 of the base 4 to allow a user to secure the adhesive-backed attachment device 1 to a surface, such as a golf cart. The adhesive 10 is preferably covered by a peel away cover 11 .
[0023] With reference to FIG. 3 , a top perspective view of a conventional stud 7 of a conventional snap 9 is illustrated.
[0024] With reference to FIG. 4 , a top perspective view of a conventional socket 13 from a conventional snap 9 is illustrated.
[0025] With reference to FIG. 5 , a side view of a vehicle enclosure 14 of the present invention attached to a golf cart using adhesive-backed attachment devices 1 is illustrated. An upper edge 16 of the vehicle enclosure 14 is attached to an inner surface 17 of a golf cart roof 18 using conventional studs 7 and adhesive-backed attachment devices 1 , as illustrated in FIG. 6 . Side edges 19 of the vehicle enclosure 14 are attached to an outer surface 20 of a body 21 of the golf cart 15 using conventional sockets 13 and adhesive-backed attachment devices 1 . The vehicle enclosure 14 is also attached to the golf cart 15 using attachment means 22 , such as conventional snaps 8 , hook and loop fasteners, zippers 23 , sleeves 24 and so forth.
[0026] With reference to FIG. 6 , a partial cross-section view along line 6 - 6 of FIG. 5 of a vehicle enclosure 14 of the present invention secured to a golf cart roof 14 is illustrated. An upper edge 16 of the vehicle enclosure 14 is attached to an inner surface 17 of the golf cart roof 18 using conventional studs 7 and adhesive-backed attachment devices 1 .
[0027] With reference to FIG. 7 , a side cutaway view of a vehicle enclosure 14 of the present invention attached to a curved surface 25 using a conventional socket 13 and a flexible adhesive-backed attachment device 1 is illustrated. The flexible adhesive-backed attachment device 1 may also be user inside curves, such as an inner corner of a golf cart roof 18 .
[0028] With reference to FIG. 8 , a bottom view of an inner surface 17 of a golf cart roof 18 having adhesive-backed attachment devices 1 of the present invention integrated therein. The adhesive-backed attachment devices 1 are integrated into side edges 26 and a rear edge 27 of the golf cart roof 24 to allow a user to easily secure a vehicle enclosure 14 to the roof using conventional snaps 8 and without having to modify the roof 18 .
[0029] With reference to FIG. 9 , a flow chart illustrating a method of installation of a vehicle enclosure of the present invention on a roof of a golf cart is shown. First, conventional snaps are attached proximate to an upper edge of a vehicle enclosure 28 . Then, adhesive-backed attachment devices are attached to the conventional snaps 29 . Next, an inner surface of the roof is cleaned 30 . Then, an adhesive-backed attachment device is secured to the inner surface of the roof using a securing means 31 . Next, the previous step is repeated until each adhesive-backed attachment device is secured to the inner surface of the roof 32 . By attaching the adhesive-backed attachment devices to the roof while the adhesive-backed attachment devices are attached to the conventional snaps and the golf cart enclosure, a user does not have to measure out attachment points on the roof and can instead eyeball the installation by starting at one corner of the vehicle enclosure and working along the upper edge of the enclosure attaching each adhesive-backed attachment device one-by-one to the roof. Finally, the remaining portions, such as side edges, bottom edges, etc., of the vehicle enclosure are attached to the golf cart using an attachment means, such as adhesive-backed fasteners of the present invention, conventional snaps, hook and loop fastener, zippers, sleeves and so forth 33 .
[0030] With reference to FIG. 10 , a flow chart illustrating a method of installation of a vehicle enclosure of the present invention on a body of a golf cart is shown. First, conventional snaps are attached proximate to a side edge of a vehicle enclosure 34 . Then an upper edge of the vehicle enclosure is attached to a roof of the golf cart using an attachment means, such as adhesive-backed fasteners of the present invention, conventional snaps, roof cover, rails, clips and so forth 35 . Next, adhesive-backed attachment devices are attached to the conventional snaps 36 . Next, the surface of the golf cart body is cleaned 37 . Then, one of the adhesive-backed attachment devices is attached to the body of the golf cart using a securing means 38 . Next, the previous step is repeated until each adhesive-backed attachment device is attached to the surface of the body 39 . Finally, any remaining unattached portions of the golf cart enclosure, such as side edges, bottom edges, etc., are attached to the golf cart using an attachment means, such as adhesive-backed fasteners of the present invention, conventional snaps, hook and loop fastener, zippers, sleeves and so forth 40 .
[0031] It is to be understood that while a preferred embodiment of the invention is illustrated, it is not to be limited to the specific form or arrangement of parts 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. | A vehicle enclosure ( 14 ) and method and system of installation using an adhesive-backed attachment device ( 1 ) having a base ( 4 ) with an adhesive backing ( 10 ) and a stud ( 12 ) or a socket ( 2 ) that engages a conventional a conventional snap ( 8 ). The adhesive-backed attachment device is preferably flexible so that it may be attached to uneven surfaces of a vehicle, such as a golf cart ( 15 ). The adhesive-backed attachment device eliminates unsightly brackets, drilling or screwing into the golf cart and cuts down on installation time of golf cart enclosures. The studs and sockets may also be integrated into a new roof ( 14 ) for retrofitting an existing golf cart. | 5 |
FIELD OF THE INVENTION
This invention generally relates to modeling or analyzing electrical circuit elements such as inductors and/or transformers so that their electrical characteristics and/or equivalent circuit parameters may be determined. The invention herein also relates to simulating the performance of electronic circuits incorporating such elements. Further, the invention relates to modeling inductors and/or transformers using a computer aided design system to facilitate design of practical elements and electronic circuits.
BACKGROUND OF THE INVENTION
Software tools for electrical engineering use may be grouped into categories according to function. Two categories are 1) circuit element modeling tools and 2) circuit design and simulation tools. Circuit element modeling tools are used to characterize a particular circuit element and create a software model for subsequent use in a circuit design and simulation program.
A model is a mathematical representation (or other type of representation) of a real world physical device (RWPD) that predicts the behavior of the real world physical device when provided with a controlled set of inputs.
Two types of models used in engineering are analytical models and numerical models. Analytical models are mathematical representations of RWPDs where a limited set of equations are used to represent a RWPD. Numerical models generally attempt to represent RWPDs by solving a more fundamental, or more physical set of equations. This often requires the solution of a large set of simultaneous equations which are restatements of a fundamental equation at different spatial or time coordinates. It will be sufficient to define a numerical model as one that requires the solution of many simultaneous equations, many more than analytical models use.
Modeling is the process of creating a model that is representative of the structure, behavior, operation, or other property of a real world physical device. Models may have other models as components, e.g. circuit models may have circuit element models.
Modeling tools use a variety of techniques to arrive at a model for a particular element, often called a device model. For example, an inductor can be modeled using commercially available software that provides a user with element parameters such as inductance and resistance for a particular geometry of the element. The modeling software can also provide element parameters over frequency in a variety of graphic or tabular formats.
Once a model is created for a circuit element, a circuit designer uses the device model in a circuit design and simulation tool, where the model is combined with other circuit element models (other device models) to form a complete circuit model. The complete circuit is then simulated using the simulation tool. The simulation tool provides a designer with circuit performance data.
Circuit designers need access to fast circuit design/simulation tools due to the iterative nature of the design process and short design cycles. Current circuit simulations often take hours or more to run. However, the preprocessing stage for the individual components, or RWPDs, usually takes much less time because less accurate analytic models are used in the interest of saving time. The time spent preprocessing is important, as this is time that the circuit designer must sit and wait at his/her terminal. To compete, the more accurate, and hence more desirable, numerical models must take no more than mere seconds, or occasionally, minutes to run. A variety of closed-form analytic models for on-chip inductors (spiral, square, etc.) can be found for the inductance, series resistance, capacitances and substrate coupling of the inductors. Since these models are only approximate models, they must be fitted (tuned) to correlate with measured data of the RWPD that spans the entire design space (the range of design variables used in the model) in order to validate and verify the model.
Model validation/verification is essentially the process of determining the degree of similarity between the model and the RWPD via comparison of measurements of the RWPD with simulation results to the same set of known(and controlled) inputs.
Factors contributing to the difficulty of this tuning process include a large variety of device types for a given circuit element (for example, inductive elements include inductors, center-tapped inductors, transformers, baluns, etc.), a broad range of parameters (design space), and widely varying process technologies. For example, in order to maximize the quality factor Q, of an inductor, the conductor line width (w) and thickness (t) become so large, one cannot make the assumption that the current density in the conductor is uniform. This non-uniform current density, (partly due to skin and/or proximity phenomena), has the effect of lowering the inductance of an inductive element by a small but often significant amount, especially in high frequency applications. Further, the non-uniform current density also has the effect of increasing the AC resistance of the inductive element. All these parameters, w, t, Q, inductance, current density, AC resistance, and more, exacerbate the modeling/tuning process.
A model created for predicting the characteristics of a circuit element should be as accurate as possible (robust). If a circuit element is not properly modeled, and a circuit is designed using that model, the circuit may not meet specifications, or perhaps, not function at all.
To further tax the robustness of analytic models, technologies using two layers of thick metal for inductors and transformers are now being considered. For example, the skin effect in a two layer, thick-metal process is more complex to model because the current in each layer will tend to crowd toward only one surface (the surface farthest from the other layer) instead of both top and bottom surfaces as in a single-layer-thick-metal process.
One motivation for desiring to employ numerical models in circuit simulation and circuit element characterization is the high level of robustness and accuracy over the entire design space that can be achieved, which is often within about 1%.
However, it is well known that numerical modeling of circuits and/or circuit elements is too slow to be of practical use in a circuit design environment. In fact, a detailed numerical model of a circuit element takes a computer many hours to obtain a solution. Long solution times are often the result of having to solve a large matrix equation. Further, many matrix operations, such as inverting a large matrix, take a very long time for even a computer to perform. Very powerful, fast computers are available to perform such calculations at a quicker pace, but they are prohibitively expensive to put on every circuit designer's desk, or even to put one in every design center.
SUMMARY OF THE INVENTION
To solve the aforementioned problems and others, it is desirable to have an accurate numerical model for inductive circuit elements contained within a circuit design environment such that it is fast enough that the circuit simulation setup time is not significantly increased, or preferably, not increased at all.
Embodiments of the invention herein include numerical modeling methods that reduces prior art device model simulation time by as much as a factor of about 3000 when simulating inductive circuit elements. Accuracies of about 1% may be achieved in as little time as about a second for a single frequency point using embodiments of the present invention.
One concept of embodiments of the present invention herein, is the applicant's recognition that the impedance matrix for an inductive circuit element has certain unique characteristics that in turn allow Strassen's method of inverting a matrix to be applied to the impedance matrix for an inductive element.
Further, Strassen's method to invert a matrix is modified such that not all of Strassen's steps need be performed to successfully invert the impedance matrix for an inductive circuit element, including, but not limited to, circular and square spiral inductors.
Another concept of the inventive method herein is to recognize that the geometry of some inductive elements are highly symmetric about a horizontal plane, thereby allowing the number of equations to be solved to be reduced by a factor of two. This is possible in these cases because the current distribution in one half of the structure is substantially the same as the current distribution in the other half of the structure that is on the other side of the plane of symmetry. Consequently, the current distribution in the entire structure may be calculated by solving a system of equations (e.g. matrix equation) with only half the number of unknowns to obtain the total inductance and resistance.
The applicant also recognizes conductors often have non-uniform current densities, such as when the skin effect is prominent at higher frequencies. This phenomenon is exploited by embodiments of the invention herein by reducing the number of equations to be solved. This is accomplished by dividing the inductive circuit element into many individual sections, where the sections in the center are larger than the sections at the edges of the conductor where the current is more concentrated and variable due to factors such as skin effect and/or proximity effects.
The overall reduction in modeling time resulting from the inventive methods herein, while still providing very high accuracy, enables circuit element (device)modeling capability to be provided within the same tool as circuit simulation software without suffering long solution times.
Using embodiments of the invention herein a circuit designer may now investigate secondary effects that have been modeled previously only by modelers using different simulation tools outside the circuit design-simulation environment. For example, the effects of variable-width spiral inductors, the effect of placing an AC bias on the inside inductor lead, or on the outside inductor lead, may now be analyzed directly by the circuit designer. Another example is the effect of continuous vias between two layers of metal used in parallel.
Secondly, tuning (tuning is the process of adjusting parameter values to make the model agree with measurements of a RWPD) to a new process would be nearly, and in some cases, totally eliminated.
Model simulation time of a particular RWPD using an embodiment of the invention herein, was reduced from 1 hour to less than 3 seconds, an overall savings in computational time of >99.9%.
It is an object of embodiments of the present invention to provide a method of very quickly inverting an impedance matrix representative of an inductive element, or group of elements.
It is another object of embodiments of the present invention to provide a method of very quickly inverting an impedance matrix representative of an inductive element, where the method is embodied in a circuit element modeling tool.
It is another object of embodiments of the present invention to provide a method of very quickly inverting an impedance matrix representative of an inductive element where the method is a modified and shortened version of Strassens's method.
It is another object of embodiments of the present invention to provide a method of very quickly inverting an impedance matrix representative of an inductive element, where the method is embodied in a circuit simulation tool.
It is another object of embodiments of the present invention to provide a circuit simulation tool that aids an operator in modeling an inductive circuit element, and further, aids an operator in simulating a circuit using the inventive numerical model.
This and other advantages and uses of the invention herein will be apparent to one of ordinary skill in the art upon reading the teaching herein.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows two of many embodiments of inductive elements suitable for modeling and how inductive elements are discretized into smaller, individual filaments in accordance with embodiments by the invention herein.
FIG. 2 shows how a plane of symmetry is used to reduce the number of equations to be solved in accordance with the invention herein.
FIG. 3 shows one method of using variable size filaments to reduce the number of equations to be solved in accordance with embodiments of the invention herein.
FIG. 4 shows alternate embodiments of the invention of FIGS. 1 and 3.
FIG. 5 shows how an impedance matrix is inverted in accordance with the invention herein.
FIG. 5A shows an alternate embodiment of the invention for inverting an impedance matrix.
FIG. 6 shows how embodiments of the present invention may be embodied in a CAD system.
FIG. 7 shows how embodiments of the present invention may be implemented as a software module for modeling circuit elements that may be executed on the system of FIG. 6 .
FIG. 8 shows how embodiments of the present invention may be implemented as a software module as part of a circuit simulation program that may be executed on the system of FIG. 6 .
DETAILED DESCRIPTION OF THE INVENTION
In the following detailed description of the embodiments, reference is made to the accompanying drawings which form a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the present invention.
Some portions of the detailed descriptions which follow are presented in terms of algorithms and symbolic representations of operations on data bits within a computer memory. These algorithmic descriptions and representations are the means used by those skilled in the data processing arts to most effectively convey the substance of their work to others skilled in the art. It has proven convenient at times, principally for reasons of common usage, to refer to these signals as bits, values, elements, symbols, characters, terms, numbers, or the like. It should be born in mind, however, that all of these and similar terms are associated with the appropriate physical quantities and are merely convenient labels applied to these quantities. Unless specifically stated otherwise as apparent from the following discussions, it is appreciated that throughout the present invention, discussions utilizing terms such as processing, computing, calculating, determining, displaying, or the like refer to the action and processes of a computer system or similar electronic computing device that manipulates and transforms data represented as physical quantities within the computer registers and memories into data similarly represented as physical quantities within the computer system memories or registers.
Inductors, such as the two non-limiting types, 2 , and 4 shown in FIG. 1, are suitable candidates to be modeled using embodiments of the invention herein. Inductor 2 (or alternatively, inductor 4 ) is first numerically discretized into 1 or more individual segments. Referring to the example in FIG. 1, inductor 2 is discretized into a plurality of segments, only some of which are shown at 6 , 8 , and 10 . The segments, such as segment 6 , may be further defined into even smaller segments as shown at 12 , 14 , and 16 . Alternatively, a single segment 7 may represent more than one section as shown in FIG. 4, or the entire inductor 2 or 4 . The invention herein does not place restrictions on how and where segments may be defined on inductor 2 .
Each segment, e.g. segment 12 , is further divided into a plurality of longitudinal filaments 18 spanning the length of the segment 12 as shown in FIG. 1 . An equivalent circuit model 22 for each filament, e.g. filament 20 , is defined. A term associated with model 22 that may also be included in constructing an impedance matrix in accordance with embodiments of the invention herein is mutual inductance 23 coupling some or all of filament pairs an example of which is shown by models 21 and 22 , where model 21 is representative of another one of filaments 18 .
Inductor 2 is discretized into N seg segments and N fil filaments. Normally, this discretization has higher resolution than is shown in FIG. 1, with the number of filaments 18 often being as many as 5000 or more. Generally speaking, the more filaments, the more accurate the model as is known in the art. Considerations that influence the choice of the number of filaments used include current distribution in the RWPD, frequency of operation, device geometry, computational time etc.
Series resistance R, series inductance L and mutual inductances M shown at 22 in FIG. 1 are calculated, in addition to other parameters, perhaps including current and current density. This involves the solution of a circuit formulation requiring the inversion of an N fil -by-N fil complex matrix, which dominates total computation time.
Since the computation time to invert a large, nonsparse matrix is approximately proportional to the cube of its size, much time can be saved by finding and using techniques that simply reduce the number of filaments 18 , and hence equations, to be solved. Embodiments of the inventive method herein reduces the number of filaments 18 , and hence the unknowns by recognizing that a plane of symmetry 24 exists along a horizontal plane of inductor 2 as shown in FIG. 2 .
For example, as shown in FIG. 2, symmetry about a horizontal plane 24 drawn through the center of at least segment 12 exists because the current distribution in the upper half 26 of segment 12 is essentially the same as the inverted current distribution in the lower half 28 of segment 12 . Further, each filament above the horizontal plane 24 has the same current as its “partner” filament below the plane (e.g. 29 , 30 ). Therefore there are actually half as many unknowns as filaments. This realization allows reduction of the matrix size by a factor of 2. Both conceptually and numerically, it is easiest to consider each filament pair above and below horizontal plane 24 , for example, filaments 29 and 30 , as a single filament.
The presence of a ground plane/die attach/paddle (not shown) may break this symmetry slightly. The effect of a paddle on inductance may be significant, but it is still small enough that the symmetry assumption is valid. This is apparent in the way that the image effect is calculated: For each filament pair 29 , 30 , the mutual inductance of one filament to the other's image in the paddle is subtracted from the non-image mutual inductance. To maintain the symmetry in this calculation, it is sufficient to replace the vertical distance between any filament and any image filament by twice the average paddle distance (or wafer thickness). Since this distance is much larger than the metal thickness, the approximation represents a small fraction of the total effect of the paddle on inductance. For a large inductor with a 250 um span, 250 um above the paddle, the image typically reduces the total inductance by ˜2%.
An additional time saving technique of the inventive method herein is to grade the widths (cross-sectional area) of filaments 18 such that smaller filaments 20 are at the surfaces of the segments (where current densities are larger and more variable), and larger filaments 31 are located toward and/or at the center (see FIGS. 3 and 4 ). This allows N fil to be reduced by approximately a factor of 4 (depending on how the grading is performed) corresponding to an approximately 64-fold increase in speed.
A necessary step when modeling inductor 2 is the inversion of a filament impedance matrix, Z f , obtained by explicitly writing the matrix equations for inductor 2 (after segmentation and “filamentation”) using circuit model 22 , and mutual inductance terms 23 , as its real and imaginary parts, yielding a 2N fil ×2N fil matrix: Z f = [ R f - ω L f ω L f R f ] [ 1 ]
Where R f is a diagonal filament resistance submatrix, L f is a filament inductance submatrix, and ω is radian frequency. L f is constructed from well known formulas as is known in the art. Note, the resistance, inductance, and mutual inductance terms of model 22 are elements of the submatrices R t and L t respectively, where “f” means filament. The submatrix elements occupy positions in the impedance matrix as denoted by conventional matrix notation a 11 , a 12 , a 21 , and a 22 .
The filament impedance matrix Z f is neither symmetric nor positive-definite. Consequently, in order to directly and reliably invert Z f , a full-pivoting technique costing (2*N fil ) 3 operations would be required. However, according to the inventive method herein, the inverse of matrix Z f may be constructed from submatrices using a modification of a method proposed by Volker Strassen (Press, William, et. al, “Numerical Recipes”, Cambridge University Press, 1986, reprinted [twice] 1987, Chapter 2.11, pages 74-76) incorporated herein by reference.
For convenience, Strassen's method is reproduced:
Defining: A = [ a 11 a 12 a 21 a 22 ] and : A - 1 = [ c 11 c 12 c 21 c 22 ]
where A is a general matrix, and A −1 is the inverse of A.
Strassen devised the following eleven-step method:
Step 1: K 1 =inverse (a 11 )
Step 2: K 2 =a 21 ×K 1
Step 3: K 3 =K 1 ×a 12
Step 4: K 4 =a 21 ×K 3
Step 5: K 5 =K 4 −a 22
Step 6: K 6 =inverse (K 5 )
Step 7: C 12 =K 3 ×K 6
Step 8: C 21 =K 6 ×K 2
Step 9: K 7 =K 3 ×C 21
Step 10: c 11 =K 1 −K 7
Step 11: C 22 =−K 6
Where the “inverse” operation indicates reciprocal if the a's and/or c's are scalars. However, “inverse” means matrix inversion if the a's and/or c's are matrices. The symbol “x” indicates multiplication.
Strassen's method has not found wide spread use because it is a more complicated process than other commonly used methods such as Gaussian elimination. Strassen's method requires more software and computational overhead, and simply does not save significant time for practical sized matrices.
An inventive concept of embodiments of the present invention is the recognition that the impedance matrix Z f for inductive circuit element 2 (and inductive elements in general) has certain unique characteristics (described infra) that in turn allow Strassen's method of inverting a matrix to be beneficially applied to the impedance matrix Z f in a way that results in a dramatic savings in time. Further, the applicant also recognizes that not all of Strassen's method need be applied to matrix Z f , resulting in an even more dramatic savings in computational time.
Inventive Method Step A
Note, when applying Strassen's method to equation [1], Z f , the following equalities apply:
a 11 =a 22 =R f , a 12 =−ωL f , a 21 =ωL f
Strassen 1. K 1 =Inverse (a 11 ):
Invert Submatrix R f : K 1 = 1 R f ,
a diagonal submatrix.
Note this step requires fewer operations than Strassen's method applied to a general case matrix because R is diagonal.
Strassen 3. K 3 =K 1 ×a 12 :
Matrix Multiply 1 R f ( - 1 ) ω L f = K 3
Note this step requires fewer operations than Strassen's method applied to a general case matrix due to the diagonality of 1 R f .
Strassen 4. K 4 =a 21 ×K 3 :
Matrix Multiply ω L f 1 R f ( - ω L f ) = K 4
Note this step requires fewer operations than Strassen's method applied to a general case matrix because the resulting matrix K 4 is symmetric about the diagonal. Ergo, only the diagonal and all terms either above or below the diagonal need be calculated.
Strassen 5. K 5 =K 4 −a 22 :
Matrix Subtract: [ ω L f 1 R f ( - ω L f ) ] - R f → yields - ω 2 L f 1 R f L f - R f = K 5 [ 2 ]
(The expression on the left may be replaced with the simplified version on the right)
Note this step requires fewer operations than Strassen's method applied to a general case matrix.
Apply Strassen 6. K 6 =Inverse (K 5 ), to [2] yielding: M 1 f = [ - ω 2 L f 1 R f L f - R f ] - 1 = K 6 [ 3 ]
and c 22 =−K 6
It can be shown that:
c 11 =c 22 , and therefore c 11 = c 22 = - K 6 = [ ω 2 L f 1 R f L f + R f ] - 1
Note this step requires fewer operations than Strassen's method applied to a general case matrix because the matrix K 5 is symmetric and positive definite allowing a special matrix inversion routine to be used that takes advantage of these properties.
Further, M 1 f is determined by inverting a symmetric, positive-definite matrix half the size of Z f , in lieu of inverting Z f directly, which, is neither symmetric nor positive-definite.
Inventive Method Step B
Apply Strassen 7. c 12 =K 3 ×K 6 , yielding: c 12 : M 2 f = ω 1 R f L f M 1 f [ 4 ]
It can be shown that, c 21 =(−c 12 )
Note this step requires fewer operations than Strassen's method applied to a general case matrix because the resulting matrix is symmetric about the diagonal.
Inventive Method Step C
Construct[Z f ] −1 : [ Z f ] - 1 = [ c 11 c 12 c 21 c 22 ] = [ M 1 f ω 1 R f L f M 1 f - ω 1 R f L f M 1 f M 1 f ]
An inventive concept of embodiments of the present invention is the recognition by the applicant that steps 2, and 8-11 of Strassen's method need not be applied due to the unique properties of the impedance matrix Z f such that a 21 =−a 12 and a 11 =a 22 (alternatively, steps 3,7, and 9-11 may be omitted with the same result). Consequently, no additional operations are required using embodiments of the inventive method herein versus many additional operations for each of Strassen's extra steps that would have had to be performed.
Comparing dominant terms in expressions for the “number of operations” for both the invention herein and Strassen's method, it can be shown the inventive technique herein requires at least >80% fewer operations ( 4 3 n 3 vs . 7 n 3 )
than Strassen's method would be if applied on a general matrix and with one step of the Strassen hierarchy. This represents a significant savings in computational time when inverting the impedance matrix Z f .
Comparing this method to Gaussian elimination, the inversion of Z f using this method is ˜6 times faster:
(4/3)n 3 vs. (2n) 3 =8n 3 operations.
Though embodiments of the inventive method herein involves two matrix multiplications, each matrix multiplication yields a symmetric matrix, of which only half the off-diagonal elements need be calculated.
The inventive method herein may be implemented in a software program used to model circuit elements and/or simulate circuit designs, one embodiment of which is shown in FIG. 5 . Referring to FIG. 5, and after segmenting and discretizing inductor 2 , an impedance matrix Z f is constructed using equivalent circuit model 22 and including the mutual inductance terms between the filaments, as shown in 32 of FIG. 5 . The inverse of matrix Z f is constructed by solving the matrix equations in 34 , 36 , and 38 and then defining the submatrices for [Z f ] −1 as shown in 40 .
Embodiments of the inventive method herein are used to provide either a lumped-element model or an S-parameter block. An advantage of lumped-element models is that they can be faster in circuit simulation. Lumped-element models may also be created at a single frequency point and still be accurate enough at other frequencies to be useful in many circuit simulations.
S-parameter blocks can also be calculated over a range of frequencies. The calculation of S-parameter blocks may be slower than calculating a lumped-element model because the calculations have to be repeated at multiple frequencies. Additionally, S-parameter blocks may be slower in circuit simulations for the same reason, however, they are much more accurate over a wide range of frequencies. If solutions over a range of frequencies are desired for constructing S-parameter blocks, the L f 1 R f L f
term may be saved and reused at each frequency to reduce the matrix multiplications from 2 to 1 per additional frequency step. Further, an overall increase in speed by a factor of 48/5 may be achieved by evaluating the L f 1 R f L f
term outside the frequency loop.
It is understood, that although embodiments of the invention herein are described in the context of planar inductors, of which octagonal and square types are shown, embodiments of the invention are also suitable for use on transformers and other types of inductors and inductive elements (e.g. resistors, baluns, ununs, spiral inductors, symmetric inductors, on-chip interconnects, etc.) realized in different technologies such as, but not limited to planar and/or three dimensional, on-chip, on a printed circuit board, or otherwise. Embodiments of the present invention are also suitable for modeling antennas and/or antenna elements such as planar structures e.g. on-chip or Printed Circuit Board distributed structures, or non-planar structures such as wire antennas. Further, embodiments of the present invention are suitable for simulating a group of lines (e.g. conductive circuit traces)either on-chip, on a printed circuit board, or otherwise.
Embodiments of the present invention may be realized in a computer system such as, but not limited to, a CAD system 52 as shown in FIG. 6 . System 52 includes CPU 58 for executing software (not shown) stored in memory 56 . The software (or firmware) contains embodiments of the present invention. An interface 60 is provided to allow an operator to input data into the system 52 , format results, and perform other well known functions associated with known modeling and/or simulation programs. A display 54 presents information to an operator such as prompts or choices to aid an operator in carrying out embodiments of the present invention, results and data formatting options as is known in the art. Display 54 may be integrated with interface 60 .
Embodiments of the invention may be implemented in software for modeling circuit elements as shown is FIG. 7, either as a stand alone program, or as a module (or portion) of a larger program performing other functions (such as simulating circuits). Regardless of the independence of the overall program, the module is entered via entry path 62 . Parameters are defined that will be used to create an element model in process 64 as described supra, with optional input 64 from an operator (perhaps in response to a prompt from the software module). The model is simulated, evaluated and presented in steps 70 - 80 , optionally with operator control as shown. The module either terminates, or proceeds to the next module if the model is acceptable as shown in steps 82 , 88 , and 90 . If the model is not acceptable, then an operator has options to tune the model (path 84 and step 68 ) or redefine the model via path 86 .
Embodiments of the invention may also be implemented in software for simulating and making circuits as shown is FIG. 8, either as a stand alone program, or as a module (or portion) of a larger program performing other functions (such as system level analysis). Regardless of the independence of the overall program, the module is entered via entry path 92 . Parameters are defined that will be used to create a circuit using element models (or creating a new element model at this point) in process 94 as described supra, with optional input 96 from an operator (perhaps in response to a prompt from the software module). The circuit is simulated, data evaluated and presented in steps 100 - 108 , optionally with operator control as shown. The module either terminates if the circuit is acceptable as shown in steps 110 and 116 , or if the circuit is not acceptable, then an operator has options to tune the circuit or element model (path 112 and step 98 ) or redefine the circuit (or element model) via path 114 .
Embodiments of the invention herein have been described and illustrated using matrices and matrix operations with a specific order of matrix operations (e.g. matrix multiplication). Applicants note that the order in which some of the matrix multiplications are performed may be changed and still be within the spirit and scope of the invention. One such alternate embodiment of the invention herein is shown in FIG. 5 A. Step 36 ′ of FIG. 5 a and step 36 of FIG. 5 show different orders of multiplying submatrices M 1 f , L f , and 1 R f .
Changing the order of these terms in steps 36 & 36 ′ (and also in step 38 , 38 ′) yields the same results for the model.
Similarly, carrying “minus signs” throughout the calculations that cancel in the final result is simply a trivially different way to describe the same method. For example, in the applicant's strict application of Strassen's Method, minus signs appear in the expression for K 5 . Yet the formulation as shown in FIGS. 5 and 5A do not show any minus signs in step 34 . The applicant recognized that the minus signs were extraneous for this particular problem. Whether a) “minus signs” are carried and then canceled, or b) dropped along the way as is understood in the art, either method yields the same result as long as it is consistently applied.
Further, applicant could have used a different convention and defined Z f as follows: Z f = [ R f ω L f - ω L f R f ] .
Though this matrix equation has its own set of solution steps, these are essentially solving the same problem in the same way. The differences being in the “minus signs”, with the approaches being the same.
It should be noted that in order to find the inverse of a matrix, it is not necessary to explicitly and completely construct the matrix to be inverted per se. It is however convenient and trivial, but not necessary. In embodiments of the invention herein, it is easy to construct submatrices ωL and R without actually performing the added step of constructing the impedance matrix per se from these submatrices.
Similarly, at the other end of the calculations, it not necessary to explicitly and completely construct the inverted impedance matrix per se from the matrices M1 and M2. However, it is convenient and trivial, but not necessary. It is possible, when implementing embodiments of the invention in simulation code (software) to continue with subsequent calculations using only M1 and M2 without actually constructing the inverted impedance matrix per se. Applicant notes that a portion of the novelty of embodiments of the invention is in how M1 and M2 are calculated from ωL and R. Descriptions of starting with the initial impedance matrix or constructing the final inverted impedance matrix per se, are used to help explain the nature of this invention, and should not be used to limit the scope of this invention in any way. Embodiments of the invention may or may not include the initial impedance matrix and/or the final fully constructed inverted impedance matrix per se.
It should be understood that the herein described methods and modules, or portions thereof, may be implemented in whole or in part in various embodiments in a machine readable medium comprising machine readable instructions for causing a computer to perform the methods or effect the operation of the modules. The computer programs run on a central processing unit out of main memory, and may be transferred to main memory from permanent storage via disk drive or CD-ROM drive when stored on removable media or via a network connection or modem connection when stored outside of the computer, or via other types of computer or machine readable media from which it can be read and utilized.
Such machine readable media may include software modules and computer programs. The computer programs may comprise multiple modules or objects to perform the described methods or the functions of the various apparatuses. The type of computer programming languages used to write the code may vary between procedural code type languages to object oriented languages. The files or objects need not have a one to one correspondence to the modules or method steps described depending on the desires of the programmer. Further, the method and apparatus may comprise combinations of software, hardware and firmware as is well known to those skilled in the art. | A method of determining electrical parameters of inductive elements includes a novel technique of inverting an impedance matrix representative of said inductive circuit element. The method reduces model simulation time by a factor of 3000. In one embodiment, simulation time of a device model was reduced from 1 hour to less than 3 seconds. The method is suitable for use with circuit element modeling tools, circuit simulation environments, and antenna modeling systems. The method may be applied to inductors, transformers, antennas, etc. | 6 |
FIELD OF THE INVENTION
The invention relates to particle impact resistant thermal barrier coatings, particularly on internal turbine components.
BACKGROUND OF THE INVENTION
Some components of gas turbine engines, such as vanes and blades, operate at temperatures up to about 1500° C. Ceramic thermal barrier coatings (TBCs) are used to insulate such components from heat, reduce surface oxidation, and reduce wear and damage caused by ingestion of foreign objects from the external air intake or from debris within the engine. Impacts from foreign objects and debris can spall the TBC, reducing its life. Hard particles commonly ranging from about 5 to 100 microns in diameter erode surfaces bounding the working gas flow path. The present coating and method reduces and controls such damage.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is explained in the following description in view of the drawings that show:
FIG. 1 is a conceptual sectional view of a multi-layer thermal barrier coating on a component substrate per aspects of the invention.
FIG. 2 is a top view of the top layer of FIG. 1 .
FIG. 3 illustrates a method according to aspects of the invention.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a sectional view of a component substrate 22 having a surface 23 with a bond coat 24 and a thermal barrier coating (TBC) 26 . The substrate may be made of a high-temperature structural material such as a nickel-based superalloy or a ceramic matrix composite. The bond coat 24 may be any type suitable for the materials of the substrate and the TBC as known in the art. For example, the bond coat 24 may be an MCrAlY alloy, where M is selected from the group of Ni, Co, Fe and their mixtures, and Y can include yttrium Y, as well as La and Hf. The bond coat may be applied for example by sputtering, electron beam vapor deposition, or low pressure plasma spraying, to provide a dense, relatively uniform layer such as about 0.02 mm to 0.25 mm thick.
The TBC 26 may comprise yttria-stabilized zirconia (YSZ) or a gadolinium zirconate (GZO) such as Gd 2 Zr 2 O 7 and/or other TBC materials known in the art. The TBC layer 26 may cover the exterior surface 23 of a turbine component in the working gas flow. Two additional protective layers 27 and 30 may cover some or all of the TBC 26 for particle impact protection.
Impact-absorbing layer 27 is a relatively soft anisotropic layer that absorbs the energy of particle impacts and stops vertical crack propagation. Layer 27 may be applied by a thermal spray process, such as plasma spray, that produces overlapping pancake-like lamellae 28 called “splats” with respective diameters oriented parallel to the substrate surface 23 , forming a porous, compliant, planar-grained layer. The overlapping splats 28 block vertical crack propagation. “Vertical” means normal to the substrate surface 23 . Layer 27 may have less than 75% of theoretical density, due to voids 29 . A desired density can be achieved by setting thermal spray parameters such as feedstock, plasma gas composition and flow rate, energy input, torch offset distance, and substrate cooling, as known in the art.
Armor layer 30 is a relatively hard layer designed to crack along vertical fractures 32 into a geometry of fracture plates 34 ( FIG. 2 ) with perimeters 33 . These plates limit impact damage horizontally to a diameter or zone, because any impact-induced horizontal cracks will stop at a vertical crack 32 , 33 . The plates 34 may have an average diameter larger than the average diameter of splats 28 in the impact-absorbing layer 27 to spread the load of the impact and allow a larger volume of the underlying layer 27 to be used to absorb the impact energy. The plates 34 form an impact-absorbing armor in conjunction with the impact-absorbing layer 27 . The fracture plates 34 may be made small enough to recoil from the particle impacts to absorb energy, yet large enough to spread the energy over a larger area than either the impact particle size or the absorbing layer grain size. For example, the fracture plates 34 may range in size from 0.25 to 2.0 mm and especially from 0.5 to 1.5 mm. A desired size range can be achieved for a given thickness of the armor layer by setting thermal spray parameters as known in the art. Alternately, a honeycomb pattern of score lines may be laser-engraved on the armor layer to promote vertical cracks in a geometry of fracture plates of a predetermined size. The armor layer may have greater than 90% of theoretical density, and especially greater than 95%.
Each protective layer 27 , 30 has a specialized role. These two layers work synergistically to limit damage both horizontally and vertically, and to absorb impact energy, thus protecting the TBC 26 . To reduce cost and weight, the protective layers 27 , 30 may be limited to areas where damaging particle impacts occur, such as the leading edges of blades, vanes, and other parts.
All layers 24 , 26 , 27 , and 30 may be applied by a thermal spray process such as plasma spray or high velocity oxygen fuel spray. The protective layers 27 and 30 may use the same materials as layer 26 , but with different spray parameters. Alternately, different materials may be used for different layers. The thickness of layer 30 may be engineered in conjunction with its hardness such that process shrinkage of layer 30 produces fracture plates 34 of the desired sizes.
FIG. 3 illustrates a method 40 per aspects of the invention, including the steps of: 42 —Form a thermal barrier coating (TBC) on a surface; 44 —Form an impact-absorbing layer on the TBC including planar grains oriented parallel to the surface; 46 —Form an armor layer on the impact-absorbing layer with fracture plates of a design size range.
The impact-absorbing layer 27 may have 10-35% greater porosity than the armor layer 30 , and especially 15-35% more porosity. For example, the TBC 26 may be formed of 7-9 mol % YSZ with 9-15% porosity, the impact-absorbing layer 27 may be formed of 7-9 mol % YSZ with 25-35% porosity, and the armor layer 30 may be formed of 7-9 mol % YSZ with 2-10% porosity.
While various embodiments of the present invention have been shown and described herein, it will be obvious that such embodiments are provided by way of example only. Numerous variations, changes and substitutions may be made without departing from the invention herein. Accordingly, it is intended that the invention be limited only by the spirit and scope of the appended claims. | A compliant, impact-absorbing layer ( 27 ) on a thermal barrier coating (TBC) ( 26 ) on a substrate ( 24 ). The impact-absorbing layer ( 27 ) has an internal structure of planar grains ( 28 ) oriented parallel to the substrate so the impact-absorbing layer preferentially fractures horizontally and it blocks vertical cracking. A ceramic armor layer ( 30 ) on the impact-absorbing layer has a higher density, and is fractured ( 32 ) into fracture plates ( 33, 34 ) of a designed size. This provides a thermal barrier with particle impact-resistance that may be applied to gas turbine components where needed. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates to a method of selectively forming an epitaxial film on a semiconductor substrate by using an insulating film as a mask and, more particularly, to a method of forming a selective epitaxial film which is improved not to form a facet on a selectively formed epitaxial film surface in contact with an insulating film.
Normally in selective epitaxial growth of silicon, an oxide film 42 is formed on the entire surface of a silicon substrate (to be referred to as a (100) silicon substrate hereinafter) 41 having a (100) plane as its surface, as shown in FIG. 1A.
Then, a rectangular opening portion 45 is formed in a desired portion of the oxide film 42 by etching. One side of the rectangular opening portion 45 is in the <100> direction.
A selective epitaxial film 43 is grown to fill the opening portion 45.
However, a (111) facet 44 having a (111) plane as its surface is undesirably formed on the surface of the selective epitaxial film 43 in contact with the oxide film 42, as shown in FIG. 1A.
Next, as shown in FIG. 1B, a polysilicon film 46 serving as, e.g., an electrode region is formed on the (100) silicon substrate 41 to cover both the oxide film 42 and the selective epitaxial film 43 having the (111) facet 44.
In this case, since the (111) facet 44 is formed, the (100) silicon substrate 41 and the polysilicon film 46 which are to be separated by the selective epitaxial film 43 undesirably contact each other and are rendered conductive, or the breakdown voltage therebetween undesirably decreases.
As one method to avoid this, Jpn. Pat. Appln. KOKAI Publication No. 6-260427 discloses the following method.
In this method, a (111) silicon substrate 51 is used, and a selective epitaxial film 53 is grown using an oxide film 52 as a mask, as shown in FIG. 2. According to this method, the surface energy of the (111) silicon substrate 51 having the (111) plane as a surface is low. For this reason, the selective epitaxial film 53 having a flat growth surface without any facet growth can be obtained as shown in FIG. 2.
In this method, however, the plane orientation of the silicon substrate 51 used for epitaxial growth is limited to the (111) plane. This method cannot be applied to the (100) plane used in normal semiconductor devices, and an application range becomes narrow.
As another method, Jpn. Pat. Appln. KOKAI Publication No. 5-182981 discloses the following method.
In this method, an oxide film 62 used as a mask for performing selective epitaxial growth on a (100) silicon substrate 61 is formed to have a special shape, i.e., a hang-over portion 64 on the interface side with a selective epitaxial growth film.
Thereafter, a selective epitaxial film 63 is epitaxially grown using disilane gas.
According to this method, the selective epitaxial film 63 having a flat surface can be obtained to fill a space defined by the side wall of the oxide film 62 and the lower surface of the hang-over portion 64 without any gap by the effect of disilane gas reflected by the lower surface of the hang-over portion 64, as shown in FIGS. 3B to 3D.
It is however very difficult to form the hang-over portion 64 on the oxide film 62.
As described above, it is difficult to obtain the selective epitaxial film 53 having a flat growth surface without any facet growth by using no mask of an oxide film in a special shape such as a hangover shape.
BRIEF SUMMARY OF THE INVENTION
The present invention has been made in consideration of the above situation, and has as its object to provide a method of forming a selective epitaxial film which can grow a selective epitaxial film having a flat growth surface without any facet growth by using no mask of an oxide film in a special shape such as a hangover shape.
To achieve the above object, according to the present invention, there is provided a method of forming a selective epitaxial film, comprising the steps of:
forming a thin film serving as a mask on an entire surface of a semiconductor substrate;
forming an opening portion reaching the surface of the semiconductor substrate in a desired region of the thin film serving as a mask;
selectively forming an epitaxial film in the opening portion; and
annealing the semiconductor substrate having the selective epitaxial film formed thereon at a temperature of 800° C. or higher.
Further, according to the present invention, there is provided a method of forming a selective epitaxial film, comprising the steps of:
forming a thin insulating film constituted by any one of a silicon nitride film, a silicon oxide film, and a multilayered film thereof on a semiconductor substrate having a (100) plane as a surface thereof;
forming an opening portion in a desired region of the thin insulating film;
growing a selective epitaxial film in the opening portion; and
annealing the semiconductor substrate having the selective epitaxial film formed thereon in a hydrogen atmosphere at a pressure of 1,000 Pa or less and a temperature of 1000 (° C.) or higher.
With the above steps, the method of forming a selective epitaxial film according to the present invention can be improved not to form a facet on a selectively formed epitaxial film surface in contact with an insulating film serving as a mask, independently of the shape of the side surface of the mask used for selective growth of the epitaxial film.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate presently preferred embodiments of the invention, and together with the general description given above and the detailed description of the preferred embodiments given below, serve to explain the principles of the invention.
FIG. 1A is a partial sectional view showing a step of forming a selective epitaxial film in the first prior art;
FIG. 1B is a partial sectional view showing a step subsequent to that in FIG. 1A;
FIG. 2 is a partial sectional view showing a process of forming a selective epitaxial film in the second prior art;
FIGS. 3A to 3D are partial sectional views, respectively, showing a process of forming a selective epitaxial film in the third prior art;
FIGS. 4A to 4C are partial sectional views, respectively, showing a process of forming a selective epitaxial film according to the first embodiment of the present invention;
FIGS. 5A to 5I are partial sectional views, respectively, showing a process of forming a selective epitaxial film according to the second embodiment of the present invention; and
FIGS. 6A to 6C are partial sectional views, respectively, showing a process of forming a selective epitaxial film according to the third embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
A method of forming a selective epitaxial film according to the first embodiment of the present invention will be described below with reference to FIGS. 4A to 4C.
As shown in FIG. 4A, an oxide film 2 with a film thickness of 200 nm is formed on the entire surface of a (100) silicon substrate 1 by thermally oxidizing the silicon substrate.
After a resist film is formed on the entire surface of the oxide film 2, an opening portion is formed in a desired portion by normal photolithography. The oxide film 2 exposed in this opening portion is etched and removed to form the oxide film 2 having an opening portion on the (100) silicon substrate 1.
As shown in FIG. 4B, silicon epitaxial growth is performed using the oxide film 2 as a mask to form a 70-nm silicon selective epitaxial film 3. At this time, the silicon selective epitaxial film 3 normally has the following shape at the interface in contact with the oxide film 2 though this shape changes depending on the growth conditions of epitaxial growth and the shape of the side surface of the opening portion of the oxide film 2.
That is, when an angle a defined by the side surface of the opening portion of the oxide film 2 and the surface of the (100) silicon substrate 1 is 90° or more, the selective epitaxial film 3 is formed in tight contact with the oxide film 2, as shown in FIG. 4C.
When, however, α is less than 90°, the silicon selective epitaxial film 3 having a (111) facet 4 on its side surface on the oxide film 2 side can be obtained, as shown in FIG. 4B.
At this time, a gap 25 is often formed at the interface of the (111) facet 4 and the oxide film 2.
Silicon selective epitaxial growth at this time is performed by flowing a carrier gas of H 2 at a flow rate of 15 l/min and a source gas of SiH 2 Cl 2 at a flow rate of 0.4 l/min at a temperature of 700° C. and a pressure of 1,000 Pa.
Subsequent to this selective epitaxial growth, annealing is performed in an atmosphere at a temperature of 1,000° C., an H 2 gas pressure of 1,000 Pa, and an impurity gas partial pressure of 1×10 -4 Pa or less for 30 sec.
At this time, it was confirmed that the (111) facet 4 of the silicon selective epitaxial film 3 formed at the interface with the oxide film 2 was filled by the silicon selective epitaxial film 3 to eliminate the gap 25, as shown in FIG. 4C.
In this manner, the side surface of the oxide film 2 directly contacts the side surface of the selective epitaxial film 3 without any gap regardless of the shape of the interface of the oxide film 2 and the selective epitaxial film 3.
This phenomenon was observed when annealing was performed in an H 2 gas atmosphere at 800° C. or higher. It is considered that atoms in the surface of the epitaxial growth layer are activated at a high temperature of 800° C. or higher and move through the surface of the epitaxial layer.
Next, a method of forming a selective epitaxial film according to the second embodiment of the present invention will be described with reference to FIGS. 5A to 5I.
The second embodiment exemplifies a case wherein a selective epitaxial film is applied to the base epitaxial film of a bipolar transistor.
Referring to FIG. 5A, a thermal oxide film 2 with a thickness of 200 nm is selectively formed on an n-type (100) silicon epitaxial growth substrate 21 which serves as a collector region and is doped with P (Phosphorus) at about 3×10 16 cm -2 , and an opening portion 30 is formed in this desired region of the thermal oxide film 2.
A p-type selective epitaxial film 23 which serves as a base region and is doped with B (Boron) at about 7×10 18 cm -2 is formed to a thickness of 70 nm.
Accordingly, a (111) facet 4 is formed on the side surface of the p-type selective epitaxial film 23 on the oxide film 2 side, and a gap 25 is partially formed (FIG. 5B).
Next, annealing is performed in an atmosphere at a temperature of 1,000° C., an H 2 gas pressure of 1,000 Pa, and an impurity gas partial pressure of 1×10 -4 Pa or less for 30 sec to fill the gap 25 (FIG. 5C).
The p-type silicon selective epitaxial film 23 is thermally oxidized to form a second silicon oxide film 5 at only the desired portion (FIG. 5D).
Subsequently, a p-type polysilicon film 6 serving as a base electrode is formed by doping B at about 5×10 18 cm -2 to cover the oxide film 2, the p-type selective epitaxial film 23, and the second silicon oxide film 5. Further, a third oxide film 7 is formed on the surface by thermal oxidation (FIG. 5E).
After a first nitride film 8 is formed on the entire surface, an etching hole 9 is formed to extend from the wafer surface to the second silicon oxide film 5 through the first nitride film 8, the third oxide film 7, and the p-type polysilicon film 6 (FIG. 5F).
Then, a second nitride film is formed on the entire surface of the wafer, and etched back to form nitride film side walls 10 on the side walls of the etching hole 9 (FIG. 5G).
Furthermore, the second silicon oxide film 5 exposed at the bottom portions of the nitride film side walls 10 is removed by wet etching to expose the surface of the silicon selective epitaxial film 23 (FIG. 5H).
An n-type polysilicon emitter electrode 11 doped with As (Arsenic) is formed to cover the surface of the nitride film side walls 10, the surface of the silicon selective epitaxial film 23 exposed at the bottom portion of the nitride film side wall 10, and further the surface of the first nitride film 8.
Annealing is performed to diffuse As (Arsenic) from the n-type polysilicon emitter electrode 11 into a portion, of the surface of the p-type selective epitaxial film 23, in contact with the n-type polysilicon emitter electrode 11, thereby forming an n-type emitter region 12 (FIG. 5I).
According to the above-described embodiments, a gap between the silicon oxide film 2 and the selective epitaxial film 3 or 23 is filled upon annealing, and an error as described above does not occur, thereby greatly improving the manufacturing yield of transistors.
Next, the third embodiment of the present invention in which the present invention is applied to element isolation will be described with reference to FIGS. 6A to 6C.
Referring to FIG. 6A, a 1,000-nm oxide film 2 is partially formed on a p-type silicon substrate 31, and an opening portion is formed using the oxide film 2 as a mask. An n-type selective epitaxial film 3 is grown on the exposed surface of the p-type silicon substrate 31 to a relatively large thickness of 1,000 nm. The silicon selective epitaxial film 3 serves as an electrically isolated device formation region (FIG. 6B).
In the use of, e.g., a (100) substrate for the p-type silicon substrate 31, however, even if the end surface of the oxide film 2 is formed vertical, a step is formed at the interface of the n-type silicon selective epitaxial film 3 and the oxide film 2 due to formation of a (111) facet 4.
This step causes disadvantages such as mask misalignment and resist coating nonuniformity in a photolithography step when a device is formed on the surface of the selective epitaxial film 3.
According to the present invention, however, the step is planarized by annealing at 800° C., and a state suitable for device fabrication can be obtained (FIG. 6C).
According to the third embodiment described above, a flat surface without almost any facet can be easily obtained, and high-precision processing can be performed with respect to the selective epitaxial film.
The above-described embodiments exemplify the case wherein selective epitaxial growth is performed on the silicon substrate. The present invention is not limited to the respective embodiments, and can be applied in a wide condition range.
The selective epitaxial film need not consist of the same material as that of the semiconductor substrate. For example, a selective epitaxial film consisting of a silicon-germanium mixed crystal may be formed on a silicon substrate.
The atmosphere of annealing is not limited to an H 2 atmosphere, and may be a non-oxidizing atmosphere such as an N 2 or Ar atmosphere so as to prevent oxidation of the surface of the semiconductor substrate.
In the respective embodiments, a silicon oxide film is used as a selective growth mask. The present invention is not limited to this, and a silicon nitride film or the like may be used.
Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents. | According to a method of fabricating a selective epitaxial film, a thin insulating film serving as a mask is formed on the entire surface of a semiconductor substrate having a (100) plane. An opening portion reaching the semiconductor substrate is formed in a desired region of the thin insulating film. An epitaxial film is selectively grown in the opening portion. The semiconductor substrate having the selective epitaxial film formed thereon is annealed at at least a pressure of 1,000 Pa and at least a temperature of 800° C. to fill a gap on the contact surface between the thin insulating film and the selective epitaxial film. | 7 |
TECHNICAL FIELD
This invention relates to fabrics and has particular reference to knitted upholstery fabrics.
DISCUSSION OF PRIOR ART
In GB-A-2,223,035, the contents of which are incorporated herein by way of reference, there is described a weft knitted double jersey upholstery fabric.
The fabric described in the specification has a structure providing a bird's eye effect on the rear face side and a plain appearance on the visible face side of the fabric.
The present invention provides a fabric having, in part, a bird's eye effect on both sides.
SUMMARY OF THE INVENTION
By the present invention there is provided an upholstery fabric of knitted double jersey construction having:
(i) a visible face side and
(ii) a rear face side of principally bird's eye structure,
which is characterized in that the fabric has on its visible face side zones of a bird's eye structure, there being on the rear face side of the said zones a plain structure.
The fabric may be knitted from textured continuous filament synthetic yarn on a machine having a gauge in the range 10 to 14 to give, in the relaxed state, a fabric having from 4 to 6 wales per cm and from 101/2 to 22 courses per cm. The yarn used preferably has a count in the range 550 to 850 decitex and a preferred yarn is air textured polyester.
It has been discovered that this type of fabric construction is stable and may be used to good effect in the formation of upholstered seats particularly for use in vehicles.
It has further been discovered that if a fabric having a bird's eye structure on the rear face side also has a bird's eye structure in register on the visible face side, an unstable structure is produced which both stretches and s liable to rapid deterioration. The provision of a plain structure on the rear face side of the zones where there is the bird's eye structure on the visible face side so that the visible face and rear face zones are substantially in register provides a balance which enables a satisfactory upholstered structure to be formed.
It will be appreciated that there need not be an exact register between the visible face and rear face zones, but as the amount of register reduces, the benefits of the invention are gradually lost.
BRIEF DESCRIPTION OF THE DRAWINGS
By way of example, embodiments of the present invention will now be described with reference to the accompanying schematic drawing, of which:
FIG. 1 is a block diagram showing a portion of fabric, and
FIG. 2 shows a stitch diagram which permits the manufacture of the fabric shown in FIG. 1.
DESCRIPTION OF PREFERRED EMBODIMENT
The method of knitting the type of fabric illustrated in the drawing is in itself well known. Reference is made to GB-A-2,223,035 mentioned above as giving ways of knitting such a fabric material. The invention is concerned with the structure of such a fabric which may therefore be knitted in manners known per se.
Referring to FIG. 1 it can be seen that there are four side-by-side zones. The left hand zone 1 has a bird's eye structure on the rear face side with colour 1 on the visible face side, the zone 2 has a bird's eye structure on the rear face side with colour 2 on the visible face side, the zone 3 has a bird's eye structure on the visible face side and colour 1 on the rear face side and in zone 4 there is a bird's eye structure on the visible face side with colour 2 on the rear face side. Each zone is 6 wales wide.
Illustrated in FIG. 2 is the stitch diagram which permits the structure of FIG. 1 to be manufactured. It can be seen that in the stitch diagram there is produced a structure by the use of two different yarns, one of colour 1 and the second yarn of colour 2. The structure is knitted in four courses on a two bed knitting machine having a rear bed R and a front bed F.
In FIG. 2 there are four adjacent zones, A, B, C and D. Zone A corresponds to zone 1 of FIG 1, zone B corresponds to zone 2 of FIG. 1, zone C corresponds to zone 3 of FIG. 1 and zone D corresponds to zone 4 of FIG. 1. In the first course (course No. 1) the first colour of yarn is knitted right-to-left. For convenience, however, the knitting is described from left to right. In zone A knitting is effected on the rear bed on alternate needles 1, 3 and 5 and on all needles on the front bed. In zone B alternate needles 7, 9 and 11 are knitted on the rear bed and no needles are knitted on the front bed. In zone C all needles are knitted on the rear bed and alternate odd numbered needles are knitted on the front bed. In zone D the knitting occurs only on alternate odd numbered needles on the front bed.
In course No. 2, yarn of colour 2 is also knitted right to left but is again described from left to right. In zone A knitting is effected on the even numbered needles on the rear bed and is not knitted on any needles of the front bed. In zone B the yarn is knitted on the even numbered needles of the rear bed and on all needles on the front bed. In zone C the yarn is knitted only on the even numbered needles of the front bed and is not knitted on any needles of the rear bed. Finally, in zone D the yarn is knitted on all needles of the rear bed and on only the even numbered needles on the front bed.
In course No. 3, in zone A, yarn of colour 1 is knitted left to right on all of the needles on the front bed but only on the even numbered needles of the rear bed. In zone B the yarn is knitted only on the even numbered needles of the rear bed and :s not knitted on the front bed. In zone C the yarn is knitted on all needles of the rear bed and on the even numbered needles of the front bed. Finally, in zone D the yarn is knitted only on the even numbered needles of the front bed.
In the final course of the sequence (course No. 4) yarn of colour 2 is knitted left to right in zone A only on the odd numbered needles of the rear bed. It is not knitted on any needles of the front bed. In zone B the yarn is knitted on all of the front needles and only on the odd numbered needles on the rear bed. In zone C the yarn is knitted on the odd numbered needles on the front bed and is not knitted on the rear bed. Finally in zone D the yarn is knitted on all of the needles on the rear bed and on the even numbered needles on the front bed.
Such a four-course structure (repeated as often as required) results in the formation of a bird's eye backed structure on the rear face side in zone A with colour showing on the visible face side. In zone B there is a bird's eye backed structure on the rear face side with colour 2 showing on the visible face side. In zone C there is a bird's eye structure on the visible face side with colour 1 showing on the rear face side and in zone D there is a bird's eye structure on the visible face side with colour 2 showing on the rear face side.
Obviously the zones for different bird's eye structures can be of any desired shape to make attractive patterns on the fabric.
If instead of using a plain structure on the rear face side of the fabric, the bird's eye structure were to be used on both the visible face and the rear face sides, the resultant structure would be unstable, and stretchy in both the wale-wise direction and the course-wise direction. Although such stretchy fabric is acceptable in garment manufacture, it is unsuitable for upholstery, as it can move around on the seat core when it is sat upon. The stretchiness also makes damage more likely to occur to the fabric in addition to its instability on the core of the seat. | An upholstery fabric of enhanced stability is formed of knitted double jersey construction and has (i) a visible face side and (ii) a rear face side of principally bird's eye structure. The fabric has on its visible face side zones of a bird's eye structure, there being on the rear face side of the said zones a plain structure. | 3 |
BACKGROUND
1. Field
This disclosure relates generally to semiconductor packages, and more specifically, to crack arrest features in semiconductor packages.
2. Related Art
Consumers demand smaller semiconductor devices with increased functionality. To achieve these desires, semiconductor devices can be decreased in size while adding additional circuitry. In wirebond packages, the additional circuitry requires additional wires to couple the semiconductor die to external terminals. Because the number of wires is increased and the size of the die is decreased, wires are likely to be closer together.
As the spacing between wires decreases, the filler in the molding compound may be blocked resulting in the mold compound having resin-rich areas. The resin-rich areas have a higher coefficient of thermal expansion (CTE) and a decreased strength than areas with more filler. When exposed to changes in temperatures, a crack is created in the resin-rich area. The crack will propagate either in the molding compound close to the die top surface or at the interface between the molding compound and the die top surface. The crack can separate the ball bond from the semiconductor die. Hence, the increased number of wires can create cracks that damage the semiconductor device. A need exists to prevent such cracks from damaging the semiconductor device.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention is illustrated by way of example and is not limited by the accompanying figures, in which like references indicate similar elements. Elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale.
FIG. 1 illustrates a top-down view of a semiconductor die assembly while flowing the molding compound to form a semiconductor package in accordance with one embodiment;
FIG. 2 illustrates a cross-section of the semiconductor package formed in FIG. 1 in accordance with one embodiment; and
FIG. 3 illustrates a cross-section of a portion of the packaged semiconductor die and a portion of the molding compound of FIG. 2 in accordance with one embodiment.
DETAILED DESCRIPTION
In one embodiment, a semiconductor package includes one or more molding compound crack stops 38 that are means for preventing cracks that occur in the molding compound 18 from extending into the active circuit region 28 of a semiconductor die 12 . The molding cracks stops 38 are located in an edge seal region 30 .
FIG. 1 illustrates a top-down view of a semiconductor die assembly 10 while forming a molding compound 18 in accordance with one embodiment. The semiconductor die assembly 10 includes a semiconductor die 12 that is coupled to a package substrate 16 through wires 14 . In one embodiment, the number of wires per length of die edge (linear wire density) is approximately 20 wires per millimeter. In one embodiment, there are 800 wires 14 coupled to the semiconductor die 12 . The semiconductor die 12 can be any semiconductor die, such as a logic device, memory device, the like, or combinations of the above. As will be better understood after further discussion, the semiconductor die 12 includes an active circuit region 28 surrounded by an edge seal region 30 . In the embodiment illustrated, the edge seal region 30 includes a molding compound crack stop 38 that also surrounds the active circuit region 28 . The edge seal region 30 is located along a periphery of the semiconductor die 12 . The active region 28 is located in an internal portion of the semiconductor die 12 . The package substrate 16 can be any suitable package substrate, such as bismaleimide triazine (BT) resin, FR4 laminate, the like, and combinations of the above. In one embodiment, the wires 14 are gold wires.
As illustrated, a molding compound 18 flows 20 from one corner of a semiconductor die assembly 10 to a diagonally opposite corner. An area near the corner where the molding compound 18 begins to flow has a nominal filler density region 22 . The nominal filler density region 22 has a filler density that is typical of the mold compound being used. For example, the nominal filler density region 22 may have silica particles that vary in size as per a normal distribution with an average diameter of approximately 30 microns. As the molding compound 18 flows 20 from one corner of the semiconductor die assembly 10 to an opposite corner, the wires 14 may block the filler in the molding compound 18 and create a low filler density region 24 . The low filler density region 24 has a filler density and concentration of filler less than that of the nominal filler density region 22 . In one embodiment, the low filler density region 24 is a resin-rich region. The filler in the molding compound 18 may be any suitable material, such as alumina, silica, boron nitride, silicon dioxide, the like, or combinations of the above.
FIG. 2 illustrates a cross-section of a semiconductor package 11 which is the semiconductor die assembly 10 of FIG. 1 after the molding compound 18 is formed over the package substrate 16 . The semiconductor package 11 includes the semiconductor die 12 formed over the package substrate 16 and coupled to the package substrate 16 through wires 14 . The semiconductor die 12 is also coupled to solder balls 26 . Due to the presence of the solder balls 26 , the semiconductor package 11 in the embodiment illustrated is a ball-grid array (BGA) package. In the embodiment illustrated, the molding compound 18 includes the low filler density region 24 under the wire 14 and adjacent the semiconductor die 12 in the corner of the semiconductor package 11 that is diagonally opposite the corner where the molding compound 18 begins to flow. In the embodiment illustrated, nominal filler density regions 22 exists over the low filler density region 24 and over the corner linearly opposite the corner where the low filler density region 24 occurs. The area under the wire 14 adjacent an edge opposite the edge where the low filler density region 24 occurs may be a nominal filler density region 22 , a low filler density region 24 , or a region that has a filler density between that of the nominal filler density region 22 and the low filler density region 24 . Hence, the filler density may vary both in the x and y directions (the directions parallel to that of the semiconductor die 12 ) and the z-direction (the direction perpendicular to the semiconductor die 12 ).
FIG. 3 illustrates a cross-section of a portion of the semiconductor die 12 and a portion of the molding compound 18 . The semiconductor die 12 includes an active circuit region 28 and an edge seal region 30 located between the active circuit region 28 and the edge 32 of the semiconductor die 12 . Thus, the edge seal region 30 is adjacent to the edge 32 and is closer to the edge 32 than the active circuit region 28 . The active circuit region 28 includes the active circuitry that is used for the functionality of the device. For example, the active circuit region 28 may include circuitry used for logic or memory functions. In the embodiment illustrated, the edge seal region 30 includes a moisture barrier 34 , a dicing crack stop 36 and a molding compound crack stop 38 .
The moisture barrier 34 may be formed to prevent moisture from penetrating into the active circuit region 28 . The moisture barrier 34 may include metal layers 40 formed over each other and electrically coupled to each other through vias 42 . In one embodiment, the metal layers 40 include copper and the vias 42 includes copper. In another embodiment, the metal layers 40 include aluminum and the vias 42 include tungsten. Any number of metal layers 40 , such as one or more metal layers 40 may be present. In addition, any number of vias 42 (e.g., one or more vias 42 ) may be formed between pairs of metal layers 40 . The moisture barrier 34 is formed within the semiconductor die in the edge seal region 30 . In one embodiment, the moisture barrier 34 is not formed.
The dicing crack stop 36 may be formed to prevent cracks created when the semiconductor die 12 is singulated (e.g., by a saw or laser) from penetrating into the active circuit region 28 . In the embodiment illustrated, the dicing crack stop 36 includes metal layers 44 over each other and electrically coupled to each other through a via 46 . In one embodiment, the metal layers 44 include copper and the via 46 includes copper. In another embodiment, the metal layers 44 include aluminum and the via 46 includes tungsten. Any number of metal layers 44 , such as one or more metal layers 44 may be present. In addition, any number of vias 46 (e.g., one or more vias 46 ) may be formed between pairs of metal layers 44 . The metal layers 44 and the via 46 are formed within the semiconductor die in the edge seal region 30 . The dicing crack stop 36 may also include a metal end cap 48 formed over the metal layers 44 to prevent the metal layer 44 from oxidizing, if the metal layer 44 is a material that would oxidize, such as copper. The metal end cap 48 may be formed over a first passivation layer 50 . The first passivation layer 50 may be formed to protect structures, within the semiconductor die 12 , such as the moisture barrier 34 . A second passivation layer 52 may be formed over the metal end cap 48 if portions of the metal end cap 48 (not shown) are used for routing. Any number of passivation layers 50 and 52 may be present. Regardless, a last passivation layer will be present. The last passivation layer is the passivation layer that does not have another passivation layer formed over it and has a portion in contact with the molding compound 18 . Hence, in the embodiment illustrated in FIG. 3 , the last passivation layer is the second passivation layer 52 and the first passivation layer is an underlying passivation layer. If the second passivation layer 52 was not present in the embodiment illustrated in FIG. 3 , then the first passivation layer 50 would be the last passivation layer.
In the embodiment illustrated in FIG. 3 , the molding compound crack stop 38 is formed over the dicing crack stop 36 . The molding compound crack stop 38 has a height 54 that extends above the last passivation layer 52 . In one embodiment, the height 54 is greater than approximately 5 microns. In another embodiment, the height 54 is approximately 10 microns and yet in another embodiment, the height is approximately 18 microns. In one embodiment where the height is approximately 18 microns, the molding compound crack stop 38 includes approximately 8 microns of copper under approximately 10 microns of a polymer. In one embodiment, the molding compound crack stop 38 includes a polymer. In another embodiment, the molding compound crack stop 38 includes multiple materials, such as a polymer and a metal. The molding compound crack stop 38 is formed over the last passivation layer 52 and is in contact with the molding compound 18 and the last passivation layer 52 . (The molding compound crack stop 38 may also be in contact with other layers or features. For example, as illustrated, the molding compound crack stop 38 may be in contact with the metal end cap 48 .) The material(s) chosen for the molding compound crack stop 38 preferably have good adhesion to the molding compound 18 and the last passivation layer 52 . Since metals do not have good adhesion to the molding compound 18 , at least a portion of the molding compound crack stop 38 , which is in contact with the molding compound, includes a polymer. Hence, in one embodiment the polymer material used for at least a portion of the molding compound crack stop 38 has an interface with the molding compound. In this embodiment, the interface includes direct contact between the molding compound and the polymer material. The polymer may be polyimide, benzocyclobutene (BCB), the like or combinations of the above. The metal can be any suitable metal, such as copper, aluminum, the like, or combinations of the above. In one embodiment the metal is copper formed by electroplating.
With the presence of the molding compound crack stop 38 when a crack is created near the edge 32 of the semiconductor die, the molding compound crack stop 38 will direct the crack to propagate in a substantially vertical direction and prevent the crack from entering the active circuit region 28 . If the crack does not enter the active circuit region 28 , then the wire 14 will not be disconnected from the semiconductor die 12 and functionality of the semiconductor die 12 will not be lost.
Although not illustrated, a glue layer may be present between the metal end cap 48 and the molding compound crack stop 38 to improve adhesion between the metal end cap 48 and the molding compound crack stop 38 . In one embodiment, the glue layer includes titanium tungsten. In another embodiment, the glue layer includes tantalum.
By now it should be appreciated that there has been provided methods and structures for preventing molding compound crack from propagating into the active circuit region 28 along the interface between the surface of the semiconductor die 12 and the molding compound 18 .
Because the apparatus implementing the present invention is, for the most part, composed of electronic components and circuits known to those skilled in the art, circuit details will not be explained in any greater extent than that considered necessary as illustrated above, for the understanding and appreciation of the underlying concepts of the present invention and in order not to obfuscate or distract from the teachings of the present invention.
Although the invention is described herein with reference to specific embodiments, various modifications and changes can be made without departing from the scope of the present invention as set forth in the claims below. For example, the molding compound crack stop 38 can be anywhere between the edge 32 of the semiconductor die 12 and the active circuit region 28 . In other words, the molding compound crack stop 38 does not need to be over the dicing crack stop 36 . Another example is that the molding compound crack stop 38 may not surround the active circuit region 28 like a ring. Instead, the molding compound crack stop 38 can be discontinuous or in any desired shape around the active circuir region 28 . Accordingly, the specification and figures are to be regarded in an illustrative rather than a restrictive sense, and all such modifications are intended to be included within the scope of the present invention. Any benefits, advantages, or solutions to problems that are described herein with regard to specific embodiments are not intended to be construed as a critical, required, or essential feature or element of any or all the claims.
The term “coupled,” as used herein, is not intended to be limited to a direct coupling or a mechanical coupling. Moreover, the terms “front,” “back,” “top,” “bottom,” “over,” “under” and the like in the description and in the claims, if any, are used for descriptive purposes and not necessarily for describing permanent relative positions. It is understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the invention described herein are, for example, capable of operation in other orientations than those illustrated or otherwise described herein. Furthermore, the terms “a” or “an,” as used herein, are defined as one or more than one. Also, the use of introductory phrases such as “at least one” and “one or more” in the claims should not be construed to imply that the introduction of another claim element by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim element to inventions containing only one such element, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an.” The same holds true for the use of definite articles. Unless stated otherwise, terms such as “first” and “second” are used to arbitrarily distinguish between the elements such terms describe. Thus, these terms are not necessarily intended to indicate temporal or other prioritization of such elements. | A package device has a package substrate, a semiconductor die on the package substrate, and a molding compound on the package substrate and over the semiconductor die. The semiconductor die has a last passivation layer, an active circuit region in an internal portion of the die, an edge seal region along a periphery of the die, and a structure over the edge seal region extending above the last passivation layer, covered by the molding compound, and comprising a polymer material. The structure may extend at least five microns above the last passivation layer. The structure stops cracks in the molding compound from reaching the active circuit region. The cracks, if not stopped, can reach wire bonds in the active region and cause them to fail. | 7 |
TECHNICAL FIELD
[0001] This invention relates to columnar aluminum titanate, a method for producing the same, and a sintered body using the columnar aluminum titanate.
BACKGROUND ART
[0002] Aluminum titanate has low thermal expansivity, excellent thermal shock resistance and a high melting point. Therefore, aluminum titanate has been expected as a porous material used such as for a catalyst support for automobile exhaust gas treatment or a diesel particulate filter (DPF), and developed in various ways.
[0003] Patent Literature 1 proposes that in order to obtain a sintered aluminum titanate body stable at high temperatures, the surface of a green body made of aluminum titanate is coated with an oxide or solid solution of one or more metals selected from magnesium, iron, silicon, titanium, and aluminum.
[0004] Patent Literature 2 proposes that in order to produce a sintered aluminum titanate body stable at high temperatures, a magnesium compound and a silicon compound are added to aluminum titanate, the resultant mixture is then formed into a green body, and the greed body is sintered.
[0005] Patent Literature 3 proposes that in order to a sintered aluminum titanate body having high strength without impairing high melting point and low thermal expansivity characteristics possessed by aluminum titanate and less degradation in mechanical strength due to repeated thermal history, a substance formed by adding magnesium oxide and silicon oxide to aluminum titanate is sintered.
[0006] Patent Literatures 4 and 5 propose a method for producing a sintered aluminum magnesium titanate body in which not less than 10% by mole to less than 100% by mole magnesium is contained in the total amount of magnesium and aluminum.
CITATION LIST
Patent Literature
[0007] Patent Literature 1: JP-A S56-41883
[0008] Patent Literature 2: JP-A 557-3767
[0009] Patent Literature 3: JP-A H01-249657
[0010] Patent Literature 4: WO 2004/039747
[0011] Patent Literature 5: WO 2005/105704
SUMMARY OF INVENTION
Technical Problem
[0012] An object of the present invention is to provide columnar aluminum titanate capable of providing a sintered body having a low coefficient of thermal expansion, a high porosity, and high mechanical strength, a production method of the same, and a sintered body of the columnar aluminum titanate.
Solution to Problem
[0013] Columnar aluminum titanate of the present invention is characterized by having an average aspect ratio (=(number average major-axis length)/(number average minor-axis length)) of 1.5 or more, preferably 1.6 or more.
[0014] With the use of the columnar aluminum titanate of the present invention having an average aspect ratio of 1.5 or more, preferably 1.6 or more, a sintered aluminum titanate body can be obtained which has a low coefficient of thermal expansion, a large pore diameter, and high mechanical strength.
[0015] No particular limitation is placed on the upper limit of the average aspect ratio, but it is generally not more than 5.
[0016] The columnar aluminum titanate of the present invention preferably contains magnesium. The magnesium content is preferably within the range of 0.5% to 2.0% by weight relative to the total amount of titanium and aluminum in terms of their respective oxides. If the magnesium content is below 0.5 in oxide terms, the resultant sintered body may not achieve a low coefficient of thermal expansion and high mechanical strength.
[0017] On the other hand, if the magnesium content is above 2.0% by weight in oxide terms, the aluminum titanate may not have any columnar shape.
[0018] The columnar aluminum titanate of the present invention preferably has a number average major-axis length of 17 μm or more and a number average minor-axis length of 15 μm or less. Within these ranges, a sintered body can be obtained which has a lower coefficient of thermal expansion, a higher porosity, and higher mechanical strength. No particular limitation is placed on the upper limit of the number average major-axis length, but it is generally not more than 50 μm. No particular limitation is also placed on the lower limit of the number average minor-axis length, but it is generally not less than 3 μm. The number average major-axis length and the number average minor-axis length can be measured by a flow particle image analyzer, for example.
[0019] A production method of the present invention is a method that can produce the columnar aluminum titanate of the present invention, and is characterized by including the steps of: mixing a source material containing a titanium source, an aluminum source, and a magnesium source while mechanochemically milling the source material; and firing the milled mixture obtained.
[0020] In the production method of the present invention, a milled mixture is used which is obtained by mixing a source material containing a titanium source, an aluminum source, and a magnesium source while mechanochemically milling the source material. By firing such a milled mixture, columnar aluminum titanate can be produced which has an average aspect ratio of 1.5 or more, preferably 1.6 or more.
[0021] The temperature for firing the milled mixture is preferably within the temperature range of 1300° C. to 1600° C. By firing the milled mixture within this temperature range, the columnar aluminum titanate of the present invention can be more efficiently produced.
[0022] No particular limitation is placed on the firing time but the firing is preferably performed for 0.5 to 20 hours.
[0023] In the production method of the present invention, an example of the mechanochemical milling is a method of milling the source material while giving it physical impact. A specific example thereof is milling using a vibration mill. It can be assumed that by performing a milling process using a vibration mill, a disorder of atomic arrangement and a reduction of interatomic distance are concurrently caused by shear stress due to frictional grinding of the powder mixture, and this causes atom transfer at contact points between different kinds of particles, resulting in the formation of a metastable phase.
[0024] Thus, a high reaction activity milled mixture is obtained. By firing the high reaction activity milled mixture, the columnar aluminum titanate of the present invention can be produced.
[0025] The mechanochemical milling in the present invention is performed in a dry process using neither water nor solvent.
[0026] No particular limitation is placed on the time of mixing involved in the mechanochemical milling, but it is generally preferably within the range of 0.1 to 6 hours.
[0027] The source material used in the present invention contains a titanium source, an aluminum source, and a magnesium source. Examples of the titanium source that can be used include compounds containing titanium oxide, and specific examples thereof include titanium oxide, rutile ores, wet cake of titanium hydroxide, and aqueous titania.
[0028] Examples of the aluminum source that can be used include compounds that can produce aluminum oxide by heat application, and specific examples thereof include aluminum oxide, aluminum hydroxide, and aluminum sulfate. Of these, aluminum oxide is particularly preferably used.
[0029] The mixing ratio of the titanium source and the aluminum source is basically Ti:Al=1:2 (in molar ratio) . However, a change of plus or minus about 10% in content of each source will present no problem.
[0030] Examples of the magnesium source that can be used include compounds that can produce magnesium oxide by heat application, and specific examples thereof include magnesium hydroxide, magnesium oxide, and magnesium carbonate. Of these, magnesium hydroxide and magnesium oxide are particularly preferably used.
[0031] The magnesium source is preferably contained in the source material to give a content of 0.5% to 2.0% by weight relative to the total amount of the titanium source and the aluminum source in terms of their respective oxides. If the magnesium content is below 0.5% by weight, a sintered body having a low coefficient of thermal expansion and high mechanical strength may not be obtained. On the other hand, if the magnesium content is above 2.0% by weight, columnar aluminum titanate having an average aspect ratio of 1.5 or more may not be obtained.
[0032] Furthermore, in the production method of the present invention, a silicon source may be further contained in the source material.
[0033] By containing a silicon source in the source material, the decomposition of aluminum titanate can be reduced, whereby columnar aluminum titanate excellent in high-temperature stability can be produced.
[0034] Examples of the silicon source include silicon oxide and silicon. Of these, silicon oxide is particularly preferably used. The content of the silicon source in the source material is preferably within the range of 0.5% to 10% by weight relative to the total amount of the titanium source and the aluminum source in terms of their respective oxides. If the content of the silicon source is within the above range, columnar aluminum titanate can be more stably produced.
[0035] A sintered aluminum titanate body of the present invention is characterized by being obtained by sintering a green body containing the above columnar aluminum titanate of the present invention or columnar aluminum titanate produced by the above production method of the present invention.
[0036] Since the sintered aluminum titanate body of the present invention is obtained by sintering a green body containing the above columnar aluminum titanate of the present invention or columnar aluminum titanate produced by the above method of the present invention, it has a low coefficient of thermal expansion, a large pore diameter, and high mechanical strength.
[0037] The above columnar aluminum titanate of the present invention or columnar aluminum titanate produced by the above method of the present invention has a low coefficient of thermal expansion and may have a negative coefficient of thermal expansion. When columnar aluminum titanate having a negative coefficient of thermal expansion is used, it can be used in mixture with aluminum titanate having a positive coefficient of thermal expansion to control the coefficient of thermal expansion of the resultant sintered body closer to zero. In the sintered aluminum titanate body of the present invention, the purpose of use of columnar aluminum titanate is not limited to the control of coefficient of thermal expansion; for other purposes, different kinds of columnar aluminum titanates of the present invention maybe used in a mixture or columnar aluminum titanate of the present invention may be used in mixture with not-inventive aluminum titanate. Alternatively, a sintered body may be produced by mixing columnar aluminum titanate of the present invention and a compound other than aluminum titanate.
[0038] The sintered aluminum titanate body in the present invention can be produced by preparing a mixture composition in which, for example, a pore forming agent, a binder, a dispersant, and water are added to aluminum titanate, forming the mixture composition into a green body providing a honeycomb structure, for example, by using an extruder, sealing one of two end openings of each cell of the honeycomb structure so that the cell end openings at each end of the honeycomb structure are arranged in a checkered pattern, drying the obtained green body and then firing the green body. The firing temperature is, for example, 1400° C. to 1600° C.
[0039] Examples of the pore forming agent include graphite, wood powder, and polyethylene. Examples of the binder include methylcellulose, ethylcellulose, and polyvinyl alcohol. Examples of the dispersant include fatty acid soap and ethylene glycol. The amounts of pore forming agent, binder, dispersant, and water can be appropriately controlled.
Advantageous Effects of Invention
[0040] Since the columnar aluminum titanate of the present invention has a low coefficient of thermal expansion and an aspect ratio of 1.5 or more, a sintered body having a low coefficient of thermal expansion, a large pore diameter, and high mechanical strength can be obtained using the columnar aluminum titanate of the present invention.
[0041] In the production method of the present invention, the columnar aluminum titanate of the present invention can be efficiently produced.
BRIEF DESCRIPTION OF DRAWINGS
[0042] FIG. 1 is a scanning electron micrograph showing columnar aluminum titanate of Example 1 of the present invention.
[0043] FIG. 2 is a scanning electron micrograph showing columnar aluminum titanate of Example 2 of the present invention.
[0044] FIG. 3 is a scanning electron micrograph showing granular aluminum titanate of Comparative Example 1.
[0045] FIG. 4 is a scanning electron micrograph showing granular aluminum titanate of Comparative Example 2.
[0046] FIG. 5 is a scanning electron micrograph showing granular aluminum titanate of Comparative Example 3.
[0047] FIG. 6 is a scanning electron micrograph showing granular aluminum titanate of Comparative Example 4.
[0048] FIG. 7 shows particle images measured by a flow particle image analyzer in Example 1 of the present invention.
[0049] FIG. 8 shows particle images measured by a flow particle image analyzer in Example 2 of the present invention.
[0050] FIG. 9 shows particle images measured by a flow particle image analyzer in Comparative Example 1.
[0051] FIG. 10 shows particle images measured by a flow particle image analyzer in Comparative Example 2.
[0052] FIG. 11 shows particle images measured by a flow particle image analyzer in Comparative Example 3.
[0053] FIG. 12 shows particle images measured by a flow particle image analyzer in Comparative Example 4.
[0054] FIG. 13 is a graph showing an X-ray diffraction pattern chart of columnar aluminum titanate of Example 1 of the present invention.
[0055] FIG. 14 is a graph showing an X-ray diffraction pattern chart of columnar aluminum titanate of Example 2 of the present invention.
[0056] FIG. 15 is a graph showing an X-ray diffraction pattern chart of granular aluminum titanate of Comparative Example 1.
[0057] FIG. 16 is a graph showing an X-ray diffraction pattern chart of granular aluminum titanate of Comparative Example 2.
[0058] FIG. 17 is a graph showing an X-ray diffraction pattern chart of granular aluminum titanate of Comparative Example 3.
[0059] FIG. 18 is a graph showing an X-ray diffraction pattern chart of granular aluminum titanate of Comparative Example 4.
DESCRIPTION OF EMBODIMENTS
[0060] Hereinafter, the present invention will be described in detail with reference to specific examples, but is not limited by the following examples.
[0061] [Production Method of Columnar Aluminum Titanate]
Example 1
[0062] An amount of 360.0 g of titanium oxide, 411.1 g of aluminum oxide, 9.7 g of magnesium hydroxide, and 19.2 g of silicon oxide were mixed for 2.0 hours while being milled by a vibration mill.
[0063] An amount of 500 g of the milled mixture obtained in the above manner was packed into a crucible and then fired at 1500° C. for four hours in an electric furnace.
[0064] An X-ray diffraction pattern chart of the obtained product is shown in FIG. 13 . As shown in FIG. 13 , the obtained product was Al 2 TiO 5 . The peaks shown at the bottom of FIG. 13 are those of Al 2 TiO 5 from JCPDS.
[0065] The obtained aluminum titanate was observed with a scanning electron microscope. FIG. 1 is a photograph from the scanning electron microscope (SEM) showing the obtained aluminum titanate. As is obvious from FIG. 1 , columnar aluminum titanate was obtained.
[0066] Furthermore, the obtained aluminum titanate was measured, by a flow particle image analyzer, in terms of number average major-axis length, number average minor-axis length, and average aspect ratio (=(number average major-axis length)/(number average minor-axis length)). FIG. 7 shows particle images measured by the flow particle image analyzer. The number average major-axis length was 21.7 μm, the number average minor-axis length was 12.6 μm, and the average aspect ratio was 1.72.
[0067] The amount of magnesium hydroxide added and the magnesium content in aluminum titanate in this example are 0.87% by weight in terms of magnesium oxide relative to the total amount of titanium oxide and aluminum oxide.
Example 2
[0068] An amount of 355.7 g of titanium oxide, 406.1 g of aluminum oxide, 18.8 g of magnesium hydroxide, and 19.0 g of silicon oxide were mixed for 2.0 hours while being milled by a vibration mill.
[0069] An amount of 500 g of the milled mixture obtained in the above manner was packed into a crucible and then fired at 1500° C. for four hours in an electric furnace.
[0070] An X-ray diffraction pattern chart of the obtained product is shown in FIG. 14 . As shown in FIG. 14 , the obtained product was Al 2 TiO 5 . The peaks shown at the bottom of FIG. 14 are those of Al 2 TiO 5 from JCPDS.
[0071] The obtained aluminum titanate was observed with a scanning electron microscope. FIG. 2 is a photograph from the scanning electron microscope (SEM) showing the obtained aluminum titanate. As is obvious from FIG. 2 , columnar aluminum titanate was obtained.
[0072] Furthermore, the obtained aluminum titanate was measured, by a flow particle image analyzer, in terms of number average major-axis length, number average minor-axis length, and average aspect ratio (=(number average major-axis length)/(number average minor-axis length)). FIG. 8 shows particle images measured by the flow particle image analyzer. The number average major-axis length was 19.5 μm, the number average minor-axis length was 11.8 μm, and the average aspect ratio was 1.65.
[0073] The amount of magnesium hydroxide added and the magnesium content in aluminum titanate in this example are 1.71% by weight in terms of magnesium oxide relative to the total amount of titanium oxide and aluminum oxide.
Comparative Example 1
[0074] An amount of 351.5 g of titanium oxide, 401.3 g of aluminum oxide, 28.5 g of magnesium hydroxide, and 18.7 g of silicon oxide were mixed for 2.0 hours while being milled by a vibration mill.
[0075] An amount of 500 g of the milled mixture obtained in the above manner was packed into a crucible and then fired at 1500° C. for four hours in an electric furnace.
[0076] An X-ray diffraction pattern chart of the obtained product is shown in FIG. 15 . As shown in FIG. 15 , the obtained product was Al 2 TiO 5 . The peaks shown at the bottom of FIG. 15 are those of Al 2 TiO 5 from JCPDS.
[0077] The obtained aluminum titanate was observed with a scanning electron microscope. FIG. 3 is a photograph from the scanning electron microscope (SEM) showing the obtained aluminum titanate. As is obvious from FIG. 3 , it can be seen that aluminum titanate obtained in this comparative example is not columnar, unlike Examples 1 and 2, but granular.
[0078] Furthermore, the obtained aluminum titanate was measured, by a flow particle image analyzer, in terms of number average major-axis length, number average minor-axis length, and average aspect ratio (=(number average major-axis length)/(number average minor-axis length)). FIG. 9 shows particle images measured by the flow particle image analyzer. The number average major-axis length was 12.3 μm, the number average minor-axis length was 8.3 μm, and the average aspect ratio was 1.48.
[0079] The amount of magnesium hydroxide added and the magnesium content in aluminum titanate in this comparative example are 2.62% by weight in terms of magnesium oxide relative to the total amount of titanium oxide and aluminum oxide.
Comparative Example 2
[0080] An amount of 360.0 g of titanium oxide, 411.1 g of aluminum oxide, 9.7 g of magnesium hydroxide, and 19.2 g of silicon oxide were mixed for 0.5 hours by a Henschel mixer.
[0081] An amount of 500 g of the mixture obtained in the above manner was packed into a crucible and then fired at 1500° C. for four hours in an electric furnace.
[0082] An X-ray diffraction pattern chart of the obtained product is shown in FIG. 16 . As shown in FIG. 16 , the obtained product was a mixture of Al 2 TiO 5 , TiO 2 , and Al 2 O 3 . The peaks shown in the lower part of FIG. 16 are those of Al 2 O 3 (aluminum oxide) , TiO 2 (rutile titanium oxide) and Al 2 TiO 3 (aluminum titanate) from JCPDS in order from the bottom.
[0083] The obtained aluminum titanate was observed with a scanning electron microscope. FIG. 4 is a photograph from the scanning electron microscope (SEM) showing the obtained aluminum titanate. As is obvious from FIG. 4 , it can be seen that aluminum titanate obtained in this comparative example is not columnar, unlike Examples 1 and 2, but granular.
[0084] Furthermore, the obtained aluminum titanate was measured, by a flow particle image analyzer, in terms of number average major-axis length, number average minor-axis length, and average aspect ratio (=(number average major-axis length)/(number average minor-axis length)). FIG. 10 shows particle images measured by the flow particle image analyzer. The number average major-axis length was 11.5 μm, the number average minor-axis length was 7.9 μm, and the average aspect ratio was 1.46.
[0085] The amount of magnesium hydroxide added and the magnesium content in aluminum titanate in this comparative example are 0.87% by weight in terms of magnesium oxide relative to the total amount of titanium oxide and aluminum oxide.
Comparative Example 3
[0086] An amount of 355.7 g of titanium oxide, 406.1 g of aluminum oxide, 18.8 g of magnesium hydroxide, and 19.0 g of silicon oxide were mixed for 0.5 hours by a Henschel mixer.
[0087] An amount of 500 g of the mixture obtained in the above manner was packed into a crucible and then fired at 1500° C. for four hours in an electric furnace.
[0088] An X-ray diffraction pattern chart of the obtained product is shown in FIG. 17 . As shown in FIG. 17 , the obtained product was a mixture of Al 2 TiO 5 , TiO 2 , and Al 2 O 3 . The peaks shown in the lower part of FIG. 17 are those of Al 2 O 3 (aluminum oxide) , TiO 2 (rutile titanium oxide) and Al 2 TiO 5 (aluminum titanate) from JCPDS in order from the bottom.
[0089] The obtained aluminum titanate was observed with a scanning electron microscope. FIG. 5 is a photograph from the scanning electron microscope (SEM) showing the obtained aluminum titanate. As is obvious from FIG. 5 , it can be seen that aluminum titanate obtained in this comparative example is not columnar, unlike Examples 1 and 2, but granular.
[0090] Furthermore, the obtained aluminum titanate was measured, by a flow particle image analyzer, in terms of number average major-axis length, number average minor-axis length, and average aspect ratio (=(number average major-axis length)/(number average minor-axis length)). FIG. 11 shows particle images measured by the flow particle image analyzer. The number average major-axis length was 11.4 μm, the number average minor-axis length was 7.8 μm, and the average aspect ratio was 1.47.
[0091] The amount of magnesium hydroxide added and the magnesium content in aluminum titanate in this comparative example are 1.71% by weight in terms of magnesium oxide relative to the total amount of titanium oxide and aluminum oxide.
Comparative Example 4
[0092] An amount of 302.3 g of titanium oxide, 423.2 g of aluminum oxide, 29.6 g of silicon oxide, and 323.7 g of water were mixed for three hours while being milled by a ball mill.
[0093] The milled mixture obtained in the above manner was dried at 110° C., and 500 g of the dried mixture was packed into a crucible and then fired at 1500° C. for four hours in an electric furnace.
[0094] An X-ray diffraction pattern chart of the obtained product is shown in FIG. 18 . As shown in FIG. 18 , the obtained product was a mixture of Al 2 TiO 5 , TiO 2 , and Al 2 O 3 . The peaks shown in the lower part of FIG. 18 are those of Al 2 O 3 (aluminum oxide) , TiO 2 (rutile titanium oxide) and Al 2 TiO 5 (aluminum titanate) from JCPDS in order from the bottom.
[0095] The obtained aluminum titanate was observed with a scanning electron microscope. FIG. 6 is a photograph from the scanning electron microscope (SEM) showing the obtained aluminum titanate. As is obvious from FIG. 6 , it can be seen that aluminum titanate obtained in this comparative example is not columnar, unlike Examples 1 and 2, but granular.
[0096] Furthermore, the obtained aluminum titanate was measured, by a flow particle image analyzer, in terms of number average major-axis length, number average minor-axis length, and average aspect ratio (=(number average major-axis length)/(number average minor-axis length)). FIG. 12 shows particle images measured by the flow particle image analyzer. The number average major-axis length was 11.7 μm, the number average minor-axis length was 8.1 μm, and the average aspect ratio was 1.44.
[0097] Table 1 shows the X-ray diffraction results, the number average major-axis lengths, the number average minor-axis lengths, and the average aspect ratios of the products of aluminum titanate of Examples 1 and 2 and Comparative Examples 1, 2, 3, and 4 obtained in the above manners.
[0000]
TABLE 1
Powder Characteristics
Amount of
Magnesium Hydroxide
Major-Axis
Minor-Axis
Added in Terms of MgO
Length
Length
Aspect
(wt %)
Mixing Method
X-Ray Diffraction
(μm)
(μm)
Ratio
Ex. 1
0.87
Vibration mill
Al 2 TiO 5
21.7
12.6
1.72
Ex. 2
1.71
Vibration mill
Al 2 TiO 5
19.5
11.8
1.65
Comp. Ex. 1
2.62
Vibration mill
Al 2 TiO 5
12.3
8.3
1.48
Comp. Ex. 2
0.87
Henschel
Al 2 TiO 5 + TiO 2 + Al 2 O 3
11.5
7.9
1.46
Comp. Ex. 3
1.71
Henschel
Al 2 TiO 5 + TiO 2 + Al 2 O 3
11.4
7.8
1.47
Comp. Ex. 4
0.00
Wet ball mill
Al 2 TiO 5 + TiO 2 + Al 2 O 3
11.7
8.1
1.44
[0098] [Production of Sintered Aluminum Titanate Body]
Example 3
[0099] Compounded into 100 parts by weight of the columnar aluminum titanate particles obtained in Example 1 were 20 parts by weight of graphite, 10 parts by weight of methylcellulose, and 0.5 parts by weight of fatty acid soap. A suitable amount of water was also added to the mixture, and the mixture was then kneaded to obtain an extrudable clay.
[0100] The obtained clay was extruded and formed into a honeycomb structure by an extruder, and the obtained green body was next dried by a microwave dryer and a hot-air dryer and then fired at 1500° C. to obtain a sintered aluminum titanate body.
Example 4
[0101] Compounded into 100 parts by weight of the columnar aluminum titanate particles obtained in Example 2 were 20 parts by weight of graphite, 10 parts by weight of methylcellulose, and 0.5 parts by weight of fatty acid soap. A suitable amount of water was also added to the mixture, and the mixture was then kneaded to obtain an extrudable clay.
[0102] The obtained clay was extruded and formed into a honeycomb structure by an extruder, and the obtained green body was next dried by a microwave dryer and a hot-air dryer and then fired at 1500° C. to obtain a sintered aluminum titanate body.
Example 5
[0103] An amount of 70 parts by weight of the columnar aluminum titanate particles obtained in Example 1 were mixed with 30 parts by weight of the granular aluminum titanate particles obtained in Comparative Example 4. Compounded into 100 parts by weight of the resultant mixed aluminum titanate particles were 20 parts by weight of graphite, 10 parts by weight of methylcellulose, and 0.5 parts by weight of fatty acid soap. A suitable amount of water was also added to the mixture, and the mixture was then kneaded to obtain an extrudable clay.
[0104] The obtained clay was extruded and formed into a honeycomb structure by an extruder, and the obtained green body was next dried by a microwave dryer and a hot-air dryer and then fired at 1500° C. to obtain a sintered aluminum titanate body.
Comparative Example 5
[0105] Compounded into 100 parts by weight of the granular aluminum titanate particles obtained in Comparative Example 4 were 20 parts by weight of graphite, 10 parts by weight of methylcellulose, and 0.5 parts by weight of fatty acid soap. A suitable amount of water was also added to the mixture, and the mixture was then kneaded to obtain an extrudable clay.
[0106] The obtained clay was extruded and formed into a honeycomb structure by an extruder, and the obtained green body was next dried by a microwave dryer and a hot-air dryer and then fired at 1500° C. to obtain a sintered aluminum titanate body.
[0107] [Evaluation of Sintered Aluminum Titanate Body]
[0108] The sintered aluminum titanate bodies obtained in Examples 3 to 5 and Comparative Example 5 were measured in terms of porosity, pore diameter, bending strength, and coefficient of thermal expansion. The porosity, pore diameter, bending strength, and coefficient of thermal expansion were measured in conformity with JIS R1634, JIS R1655, JIS R1601, and JIS R1618, respectively. The measurement results are shown in Table 2.
[0000]
TABLE 2
Sintered Body Characteristics
Porosity
Pore Diameter
Strength
CTE
(%)
(μm)
(MPa)
×10 −6 /° C.
Ex. 3
39.2
8.4
7.5
−1.2
Ex. 4
40.3
7.9
7.4
−1.0
Ex. 5
39.0
7.1
6.5
0.1
Comp. Ex. 5
38.7
4.6
4.3
2.1
[0109] As shown in Table 2, it can be seen that the sintered aluminum titanate bodies of Examples 3 to 5 produced using columnar aluminum titanate of the present invention have larger pore diameters, higher mechanical strength, and lower coefficients of thermal expansion than the sintered aluminum titanate body of Comparative Example 5. It can be therefore seen that the sintered aluminum titanate body of the present invention has low thermal expansivity, excellent thermal shock resistance, high mechanical strength, and high efficiency of particulate capture.
[0110] In addition, as is obvious from Example 5, the thermal expansivity of the sintered body can be controlled by mixing columnar aluminum titanate with conventional granular aluminum titanate. | Provided are aluminum titanate capable of providing a sintered body having a low coefficient of thermal expansion, a high porosity, and high mechanical strength, a production method of the same, and a sintered body of the columnar aluminum titanate. The columnar aluminum titanate has an average aspect ratio (=(number average major-axis length)/(number average minor-axis length)) of 1.5 or more and its magnesium content is preferably within the range of 0.5% to 2.0% by weight relative to the total amount of titanium and aluminum in terms of their respective oxides. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional application of prior, co-pending U.S. patent application Ser. No. 10/625,155, filed 23 Jul. 2003, which is incorporated herein by reference for all purposes.
BACKGROUND
[0002] 1. Field of the Invention
[0003] The present invention relates to a method of and apparatus for detecting diseased tissue. In particular, the present invention provides a noninvasive method of detecting diseased tissue by sensing skin temperature, the homogeneity thereof, the temporal variation thereof and the correlation thereof using a sensor detecting two different bands of infrared wavelengths.
[0004] 2. Description of Related Art
[0005] In the field of diseased or cancerous tissue detection, many methods require subjecting the patient to doses of X-ray radiation or to painful biopsies, especially for breast cancer detection. More recently, researchers discovered that dysfunction of the neuronal control of the vasculature due to cancerous lesions leads to temporal or periodic perfusion changes. By measuring, recording and analyzing these periodic perfusion changes, typically through infrared (IR) imaging, diseased or cancerous tissue can be detected. While these periodic perfusion changes appear to be associated with most types of diseased or cancerous tissue, skin cancer and other cancers near the surface of the skin are most likely to be detected using IR imaging. Such a method is described in U.S. Pat. Nos. 5,810,010, 5,961,466 and 5,999,843, all to Michael Anbar, and hereby incorporated by reference.
[0006] In particular, breast cancer appears to be very susceptible to detection through IR imaging. Breast cancer detection by this method involves taking a series of IR images of the breast. This series of IR images will show both neuronal control and non-neuronal control of periodic perfusion changes in a cancerous breast. These IR images are then converted into thermal images with a temperature associated with each portion of the thermal image. The thermal images are then analyzed by finding the average temperature and standard deviation of temperature for each subarea within the thermal images. Clusters of subareas having abnormal average temperatures or standard deviations are indicative of cancer. It is anticipated that breast cancer may generally be detected by imaging the appropriate lymph nodes, the so-called “signal nodes,” which tend to have increased biological activity if cancer is present.
[0007] The frequency of the periodic perfusion changes can also be used to detect cancer. Neuronal control generally has a lower frequency than non-neuronal control of periodic perfusion. Therefore, by analyzing the thermal images and determining the periodic perfusion frequency for each of the subareas, clusters of subareas having higher frequencies are indicative of cancer.
[0008] The use of IR images for cancer detection places very stringent requirements on an IR imager. The small temperature changes associated with neuronal and non-neuronal perfusion require an IR imager sensitivity of less than 0.01° C. While IR imagers having this level of sensitivity have been demonstrated, these IR imagers have not successfully been built in quantity.
[0009] In view of the desirability of non-invasive means of cancer detection that do not require subjecting the patient to X-ray radiation exposure, there exists a need for a method that places lower requirements upon IR imager sensitivity. A method that requires lower sensitivity will lead to increased manufacturability and lower IR imager cost. Lower cost IR imagers can lead to greater accessibility to cancer screening and detection.
SUMMARY OF THE INVENTION
[0010] A first embodiment of the present invention comprises a method of detecting diseased tissue including recording first and second series of IR images of a predetermined area of tissue. The first and second series of IR images are recorded in corresponding first and second bands of IR wavelengths, the two bands of IR wavelengths being different. The first and second series of IR images are converted into corresponding first and second series of thermal images. The predetermined area of tissue is subdivided into a plurality of subareas. A first plurality of average temperature values is determined for each of the plurality of subareas from a corresponding one of the first series of thermal images. A first average temperature is determined using the first plurality of average temperature values. A second plurality of average temperature values is determined for each of the plurality of subareas from a corresponding one of the second series of thermal images. A second average temperature is determined using the second plurality of average temperature values. The resulting first and second pluralities of average temperature values for each of the plurality of subareas is then analyzed for possible diseased tissue. Tissue corresponding to a cluster of at least six adjacent subareas having a spatial distribution of corresponding first plurality of average temperature values that is less than about 20% or more than about 100% of the first average temperature is preliminarily determined to be diseased. Tissue corresponding to the cluster preliminarily determined to be diseased is further analyzed. If the cluster has a spatial distribution of corresponding second plurality of average temperature values that is less than about 20% or more than about 100% of the second average temperature, tissue corresponding to the cluster is confirmed to be diseased.
[0011] Another embodiment of the present invention comprises a method of detecting diseased tissue including recording first and second series of IR images of a predetermined area of tissue. The first and second series of IR images are recorded in corresponding first and second bands of IR wavelengths, the two bands of IR wavelengths being different. The first and second series of IR images are converted into corresponding first and second series of thermal images. The predetermined area of tissue is subdivided into a plurality of subareas. A first plurality of average temperature values and a first plurality of temperature standard deviations are determined for each of the plurality of subareas from a corresponding one of the first series of thermal images. A second plurality of average temperature values and a second plurality of temperature standard deviations are determined for each of the plurality of subareas from a corresponding one of the second series of thermal images. For each of the plurality of subareas, each corresponding one of the first plurality of average temperature values is divided by a corresponding one of the first plurality of temperature standard deviations to determine a corresponding one of a first plurality of homogeneity of skin temperature (HST) values for the plurality of subareas. For each of the plurality of subareas, each corresponding one of the second plurality of average temperature values is divided by a corresponding one of the second plurality of temperature standard deviations to determine a corresponding one of a second plurality of HST values for the plurality of subareas. A first average HST value is determined using the first plurality of HST values while a second average HST value is determined using the second plurality of HST values. The resulting first and second pluralities of HST values for each of the plurality of subareas are then analyzed for possible diseased tissue. Tissue corresponding to a cluster of at least six adjacent subareas having a corresponding spatial distribution of first plurality of HST values that is less than about 20% or more than about 100% of the first average HST value is preliminarily determined to be diseased. Tissue corresponding to the cluster preliminarily determined to be diseased is further analyzed. If the cluster has a corresponding spatial distribution of second plurality of HST values that is less than about 20% or more than about 100% of the second average HST value, tissue corresponding to the cluster is confirmed to be diseased.
[0012] In yet another embodiment, the present invention comprises a method of detecting diseased tissue including recording first and second series of infrared images of a predetermined area of tissue. The first and second series of infrared images are recorded in respective first and second bands of infrared wavelengths, with the second band of infrared wavelengths different from the first band of infrared wavelengths. The first and second series of infrared images are converted into corresponding first and second series of thermal images. The predetermined area of tissue is subdivided into a plurality of subareas. A first plurality of average temperature values is determined for each of the plurality of subareas, with each of the first plurality of average temperature values for each of the plurality of subareas being determined from one of the first series of thermal images. A second plurality of average temperature values is determined for each of the plurality of subareas, with each of the second plurality of average temperature values for each of the plurality of subareas being determined from one of the second series of thermal images. First and second radiance measurements are taken at respective first and second bands of infrared wavelengths of known healthy tissue. The first and second radiance measurements of known healthy tissue are correlated. The first and second plurality of average temperature values for each of the plurality of subareas are correlated. The correlated first and second plurality of average temperature values for each of the plurality of subareas is then analyzed. When a spatial distribution of slopes of the correlated first and second plurality of average temperature values corresponding to a cluster comprising at least six adjacent subareas is different from a slope of the correlation of known healthy tissue, tissue corresponding to the cluster is determined to be diseased.
[0013] In still another embodiment, the present invention comprises a method of detecting diseased tissue including recording first and second series of IR images of a predetermined area of tissue. The first and second series of IR images are recorded in corresponding first and second bands of IR wavelengths, the two bands of IR wavelengths being different. The first and second series of IR images are converted into corresponding first and second series of thermal images. The predetermined area of tissue is subdivided into a plurality of subareas. A first plurality of average temperature values and a first plurality of temperature standard deviations are determined for each of the plurality of subareas from a corresponding one of the first series of thermal images. A second plurality of average temperature values and a second plurality of temperature standard deviations are determined for each of the plurality of subareas from a corresponding one of the second series of thermal images. A first average temperature standard deviation is determined using the first plurality of temperature standard deviations. A second average temperature standard deviation is determined using the second plurality of temperature standard deviations. The resulting first and second pluralities of temperature standard deviations for each of the plurality of subareas are then analyzed for possible diseased tissue. Tissue corresponding to a cluster of at least six adjacent subareas having a spatial distribution of corresponding temperature standard deviations that is less than about 20% or more than about 100% of the first average temperature standard deviation is preliminarily determined to be diseased. Tissue corresponding to the cluster preliminarily determined to be diseased is further analyzed. If the cluster has a corresponding spatial distribution of second plurality of temperature standard deviations that is less than about 20% or more than about 100% of the second average temperature standard deviation, tissue corresponding to the cluster is confirmed to be diseased.
[0014] In further embodiments, alternative data analysis is possible. This alternative data analysis may include finding contributing frequencies for each subarea and determining that tissue corresponding to a cluster having a spatial distribution of less than a lower threshold frequency or more than an upper threshold frequency is diseased. The data may undergo fast Fourier analysis for this frequency determination. The data in the two series of thermal images can be correlated with diseased tissue having a different correlation intercept than healthy tissue. The contrast in the two series of IR images can be enhanced by subjecting the predetermined area of tissue to thermal stress, such as by directing a cooling flow of air across the area of tissue.
DESCRIPTION OF THE DRAWINGS
[0015] The present invention is described in reference to the following Detailed Description and the drawings in which:
[0016] FIG. 1 is diagram of the blood perfusion process that can be detected by embodiments of the present invention,
[0017] FIG. 2 is an average temperature histogram generated by a first embodiment of the present invention,
[0018] FIG. 3 is a contributing frequency histogram generated by second and third embodiments of the present invention,
[0019] FIG. 4 is a correlation plot generated by fourth and fifth embodiments of the present invention,
[0020] FIG. 5 is an HST value histogram generated by sixth and seventh embodiments of the present invention,
[0021] FIG. 6 is a temperature standard deviation histogram generated by an eighth embodiment of the present invention
[0022] FIG. 7 is a block diagram of an apparatus for implementing the first through third embodiments of the present invention,
[0023] FIG. 8 is a block diagram of an apparatus for implementing the fourth and fifth embodiments of the present invention,
[0024] FIG. 9 is a block diagram of an apparatus for implementing the sixth and seventh embodiments of the present invention, and
[0025] FIG. 10 is a block diagram of an apparatus for implementing the eighth embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0026] Various embodiments of the present invention are described in detail with reference to the drawings. While the following description will generally discuss each embodiment separately, two or more embodiments may be combined to increase the accuracy of diseased or cancerous tissue detection. Further, while the present description will generally use only two bands of IR wavelengths, the use of three or more bands of IR wavelengths will further increase system sensitivity to diseased tissue.
[0027] FIG. 1 illustrates an area of tissue and skin 100 , of which a portion is diseased, such as by a cancerous lesion. This area of tissue and skin 100 is imaged by a diagnostic system 110 employing the methodology of the present invention. The diagnostic system 110 comprises a dual-band IR imager 112 and a computer 114 .
[0028] In the healthy portion of the area of tissue and skin 100 , the body regulates its temperature using neuronal modulation of blood perfusion 120 . The neuronal modulation of blood perfusion 120 includes vasodilation to cool the body and vasoconstriction to warm the body in the body's effort to maintain a desired temperature 122 . This results in normal temperature oscillations 124 about the desired temperature 122 . The body uses the skin as a radiator to remove excess heat causing the skin temperature 126 to oscillate. The skin temperature 126 oscillates over a band of neuronal thermoregulatory frequencies (TRFs) 128 . The skin therefore radiates an IR flux 130 as excess heat is given off by the skin in the body's effort to maintain the desired temperature 122 . While this process is generally discussed in terms that the tissue underlying the skin is cancerous, this method lends itself to the detection of skin cancer as well. For that reason, while the term tissue and skin may be used separately, skin will also be considered tissue for the purposes of this description.
[0029] The diagnostic system 110 takes a series of infrared images of the tissue and skin 100 using the dual-band IR imager 112 and processes the resultant images using the computer 114 . The actual images will be composed of many individual pixels, each corresponding to a different portion of the imaged tissue and skin 100 . The dual-band IR imager 112 may be based upon a 256 pixel by 256 pixel or 480 pixel by 640 pixel dual-band IR photodetector array. To increase sensitivity, the dual-band IR imager 112 images the tissue and skin 100 in two different bands of IR wavelengths resulting in two different series of IR images. By using the two different series of IR images, the occurrence of false positives and false negatives may be reduced. The second series of IR images in the second band of IR wavelengths may serve as a check on the first series of IR images in the first band of IR wavelengths, thereby increasing overall diagnostic system I 10 sensitivity depending upon the data analysis method. The use of N independent bands of IR wavelengths generally leads to a √N increase in sensitivity. With the two bands used throughout this description, this increase in sensitivity leads from a single band IR diagnostic system having a sensitivity of 30 m° C. to a dual-band IR diagnostic system 110 having a sensitivity of 21 m° C. Alternatively, if 30 m° C. is the desired diagnostic system 110 sensitivity, then the dual-band IR imager 112 can incorporate two single-band IR photodetector arrays each having a sensitivity of 42 m° C., thereby improving manufacturability.
[0030] The increased sensitivity of the dual-band IR imager 112 over a single-band IR imager decreases the occurrence of false positive and false negatives due to tissue and skin variations. Different portions of the skin may radiate different levels of IR flux, even though both the skin and the underlying tissue are healthy. As an example, a birthmark will likely radiate heat differently than normal skin. Similarly, a tattoo may create a false positive or false negative, as it too will radiate heat differently than normal skin. For a very sensitive single-band IR imager, a large freckle may lead to a false positive or false negative. However, by using two series of IR images, each taken in different bands of IR wavelengths, false positives and false negatives due to variations in skin color will be minimized. Variations in the underlying tissue can also affect detection of diseased tissue. While a breast may have relatively uniform tissue, an arm will include areas of significant muscle tissue adjacent to bony regions such as the elbow and wrist, resulting in IR image variations.
[0031] The nitric oxide (NO) modulation of blood perfusion 140 will be described next. A diseased portion of the tissue and skin 100 , due to a cancer 142 in this discussion, provokes an immune response 144 within the tissue and skin 100 . This immune response 144 results in increased macrophage activity 146 , which produces NO 148 . Some cancers, such as breast cancer, are known to elevate the local level of ferritin 150 within the diseased tissue. Elevated levels of ferritin 150 further increases the amount of NO 148 produced within the diseased tissue. Nitric oxide causes vasodilation 152 of the capillary bed leading to enhanced blood perfusion 156 within the diseased tissue. A side effect of the presence of NO is that neuronal control (vasodilation and vasoconstriction) of the capillary bed is impaired 154 . The net result is that temperature in the diseased tissue will be controlled more by NO-based blood perfusion rather than by neuronal processes. That is, NO controlled temperature oscillations 158 will dominate over the attenuated neuronal temperature oscillations 160 .
[0032] A second side effect of NO controlled blood perfusion is an increase in spatial homogeneity of skin temperature 162 . That is, there will be less temperature variation in the skin surface temperature due to the NO-induced vasodilation of the capillary bed. NO controlled blood perfusion will occur at non-neuronal TRFs 164 , as will be discussed in detail below. As with healthy tissue, the temperature of the skin overlying diseased tissue will create an IR flux 166 that can then be imaged by the dual-band IR imager 112 .
[0033] The first embodiment of the present invention is based upon the average temperature of the imaged tissue. The first embodiment converts the first and second series of IR images into thermal images, i.e., converts each pixel from the IR image to a corresponding temperature. Each individual thermal image therefore is a two-dimensional array of temperatures and each of the first and second series of thermal images is a series of two-dimensional arrays of temperatures. At the preferred imaging rate of 30 to 60 images per second and a 10 to 60 second series of images, the first and second thermal images can readily include over 1000 individual thermal images. The first embodiment next subdivides the tissue area imaged into a number of subareas. These subareas correspond to two pixel by two pixel portions of the thermal images or larger. A preferred upper limit on the subarea size is an eight pixel by eight pixel subarea as larger areas will tend to average out any local variations that might indicate the presence of diseased tissue.
[0034] The first embodiment then finds the average temperature value for each of these subareas. This is done for each individual thermal image in both the first and the second series of thermal images resulting in first and second pluralities of average temperature values. These first and second pluralities of average temperature values are then analyzed in view of FIG. 2 . FIG. 2 illustrates a histogram showing all of the average temperature values for the first plurality of average temperature values 200. Curve 202 is the composite curve showing the average temperature values for skin overlying both healthy and diseased tissue. Curve 204 corresponds to the average temperature values for the skin overlying a healthy region of tissue. Curve 204 therefore corresponds to skin whose underlying tissue is thermally regulated by neuronal control of blood perfusion. The peak temperature value for this healthy tissue is denoted T H . In regions of skin overlying diseased or cancerous tissue, the average temperature value curve 206 is formed. Due to the generally vasodilated state of the capillary bed in diseased tissue, the average temperature value for these regions is greater. The higher peak average temperature value for these diseased regions is denoted by T D.
[0035] A preliminary determination that a cancerous lesion may be present requires that a cluster of six adjacent subareas each have abnormal average temperature values. A first average temperature value for the first series of thermal images is calculated. This first average temperature value is preferably found by proportionately weighting each of the subareas based upon their size. In particular, when a spatial distribution of the first average temperature values within the cluster of six adjacent subareas is less than about 20% or more than about 100% of the first average temperature value, tissue corresponding to the cluster of six adjacent subareas is preliminarily determined to be diseased. This preliminary determination is confirmed if the same series of calculations and comparisons on the second series of thermal images yields the same cluster of six adjacent subareas.
[0036] As each of the first and second series of IR images is preferably taken periodically, TRFs can be determined. The second embodiment of the present invention makes use of these TRFs. FIG. 3 illustrates a TRF histogram for both healthy and diseased tissue 300 . Curve 302 is a composite for both the healthy and diseased tissue while curve 304 corresponds to healthy tissue and curve 306 corresponds to diseased tissue. Curve 304 for healthy tissue reflects neuronal control blood perfusion and generally has a frequency of between 10 and 700 milliHertz. In contrast, curve 306 for diseased tissue reflects NO-based control of blood perfusion and has a higher frequency, generally in the range of 0.8 to 2.0 Hz.
[0037] The second embodiment makes use of the differences in TRFs by finding the contributing frequency for each subarea in the first series of thermal images. This contributing frequency may be determined by analyzing the average temperature value for a subarea based on the known periodic nature of the first series of thermal images. The preferred method to determine the contributing frequency is to subject the average temperature values to a fast Fourier transform that rapidly finds the frequency components or ranges of frequencies for a time varying signal. As shown in FIG. 3 , while more healthy tissue subareas had a TRF of F H , there is some variation about this frequency. However, very few healthy tissue subareas had a TRF as high as F D , the strongest of the diseased tissue TRFs. Once the contributing frequency for each subarea using the first series of thermal images is determined, first lower and upper threshold frequencies are found, preferably by weighting each subarea based upon their size. As before, a cluster of six adjacent abnormal subareas leads to a preliminary diseased tissue diagnosis. In particular, when a spatial distribution of the contributing frequency of the cluster is less than the first lower threshold frequency or more than the first upper threshold frequency, tissue corresponding to the cluster is preliminarily diagnosed as being diseased. This preliminary diagnosis is confirmed if the same series of determinations and comparisons on the second series of thermal images yields the same cluster of six adjacent subareas.
[0038] The third embodiment is similar to the second embodiment in that it uses the contributing frequency of each subarea. In particular, the third embodiment uses the amplitude of the contributing frequencies. As shown in FIG. 3 , the diseased tissue curve 306 has only a small frequency amplitude at F H , thus providing another means for cancer discrimination. The third embodiment therefore searches for a cluster in which a spatial distribution of the amplitude of the contributing frequency is less than a first lower threshold amplitude or more than a first upper threshold amplitude. The first lower and upper threshold amplitudes are determined using the first series of thermal images and is preferably weighted by subarea size. As with the previous embodiments, the use of the second series of thermal images is used to confirm a preliminary diseased diagnosis from the first series of thermal images.
[0039] In contrast to the first three embodiments that use the two series of thermal images sequentially, the fourth embodiment uses the two series of thermal images in parallel. FIG. 4 illustrates a series of correlation curves 400 for two different bands of IR wavelengths, the two bands centered around λ 1 and λ 2 . The fourth embodiment includes taking a baseline radiance measurement of known healthy skin and tissue in the two different bands of IR wavelengths, thereby generating a healthy skin and tissue correlation curve 402 . This healthy correlation curve 402 can be mathematically defined most simply in terms of a slope and an intercept, that is λ 2 =M H λ 1 +b H . It should be noted that depending upon the wavelengths within the two bands of IR wavelengths, the properties of the skin and underlying tissue, etc., additional terms might be required to more accurately describe the correlation. In the simple slope and intercept form, the precise values for m H and b H will likely be a function of the skin and the underlying tissue. For example, the m H and b H values for a breast cancer screening will likely be different from the m H and b H values for a bony structure such as the wrist or ankle. Once the appropriate healthy correlation curve 402 is determined, the subareas within the first and second series of thermal images will also be correlated. This correlation may produce subareas having diseased correlation curve 404 or 406 . Diseased correlation curve 404 may be described as λ 2 =m D1 λ 1 +b D1 , while diseased correlation curve 406 may be described as λ 2 =m D2 λ 1 +b D2 . The fourth embodiment then compares the slope m D1 or m D2 with m H . If a spatial distribution of the m D1 or m D2 values for a cluster are different than m H , then the tissue corresponding to the cluster is determined to be diseased. How different the slope values will be will depend upon the types of underlying tissue as noted above, as well as the specific wavelengths λ 1 and λ 2 chosen.
[0040] The radiance measurements of healthy skin taken for the fourth embodiment may be made as a function of integration time for the dual-band IR imager 112 , the temperature of the skin and tissue being imaged, or a combination thereof. The temperature of the skin and tissue can be varied by directing either a warming or a cooling stream of air on the skin and tissue resulting in thermal stress to the skin and tissue. Alternatively, this thermal stress may be induced by directing a flow of water vapor to the skin and tissue. While this thermal stress finds particular application with the fourth (and fifth) embodiments, it can readily be used in conjunction with the other embodiments as well.
[0041] Due to the oscillatory nature of thermal regulation, the sensitivity of the fourth (and fifth) embodiments can be increased. By finding the contributing frequency for each of the subareas, the correlation between the two series of thermal images can be made at neuronal frequencies or at NO modulation frequencies. It is anticipated that correlations made at NO modulation frequencies will be especially sensitive for discriminating healthy versus diseased skin and tissue regions.
[0042] While the fourth embodiment uses the slope of the correlation between the two series of thermal images, the fifth embodiment uses the intercept of the correlation between the two series of thermal images. To this end, the fifth embodiment compares b D1 or b D2 with b H . When the spatial distribution of b D1 or b D2 for a cluster are different from b H , tissue corresponding to the cluster is diagnosed as being diseased. As before, this difference is a function of the underlying tissue and the specific wavelengths chosen.
[0043] The sixth embodiment of the present invention is based upon detectable differences in the HST between healthy and diseased skin and tissue. The HST for a subarea is found by determining both the average temperature value and the temperature standard deviation and then dividing the average temperature value by the temperature standard deviation. The HST is found for each subarea for each of the first series of thermal images. FIG. 5 shows the resultant histogram 500 of HST values from the first series of thermal images for the skin overlying both healthy and diseased tissue. Curve 502 is the overall HST curve while curve 504 corresponds to healthy skin and tissue while curve 506 corresponds to diseased skin and tissue. The temperature standard deviation found in diseased tissue is lower than that of healthy tissue due to the overall vasodilated state of the capillary bed. This lower standard deviation results in higher HST values for diseased skin and tissue regions, centered about HST D as shown in FIG. 5 . In contrast, healthy skin and tissue temperature is controlled by neuronal processes that include both vasodilation and vasoconstriction. This results in wider variations in skin temperature, larger temperature standard deviations and therefore smaller HST values. FIG. 5 shows the healthy skin and tissue regions to have HST values centered about HST H . An overall first average HST for the first series of thermal images is also computed. A preliminary diseased tissue diagnosis is made when spatial distribution of a cluster of six adjacent subareas have HST values of less than about 20% or more than about 100% of the first average HST. This preliminary diagnosis is confirmed if the same series of calculations and comparisons on the second series of thermal images yields the same cluster of six adjacent subareas.
[0044] The seventh embodiment makes use of the differences in TRFs of the HST values by finding the contributing frequency for each subarea in the first plurality of HST values. The seventh embodiment will generate a frequency histogram similar to that of FIG. 3 in that healthy tissue subareas will have a TRF of HST values with some variation about a healthy tissue center frequency. Likewise, diseased tissue subareas will have TRF of HST values with some variation about a higher diseased tissue center frequency. Once the contributing TRF of HST values for each subarea using the first series of thermal images is determined, a first average contributing frequency is found. A cluster of six adjacent abnormal subareas leads to a preliminary diseased tissue diagnosis. In particular, when a spatial distribution of the magnitude of the contributing TRF of HST values of the cluster is less than about 20% or more than about 100% of the first average contributing frequency, tissue corresponding to the cluster is preliminarily diagnosed as being diseased. This preliminary diagnosis is confirmed if the same series of determinations and comparisons on the second series of thermal images yields the same cluster of six adjacent subareas.
[0045] FIG. 6 illustrates a temperature standard deviation histogram 600 employed by the eighth embodiment of the present invention. The eighth embodiment requires determining the temperature standard deviation for each of the subareas for each one of the first series of thermal images. Curve 602 corresponds to the resultant overall histogram for the temperature standard deviations and is a combination of a curve 604 representing the temperature standard deviations for healthy skin and tissue and curve 606 representing the temperature standard deviations for diseased skin and tissue. The standard deviation for diseased skin and tissue will be lower as noted above due to the generally vasodilated state of the capillary bed leading to more constant temperatures relative to skin and tissue under neuronal controlled blood perfusion. A preliminary diagnosis of diseased skin and tissue corresponding to a cluster of six adjacent subareas requires the cluster to have a spatial distribution of temperature standard deviation of less than about 20% or more than about 100% of a first average temperature standard deviation based upon the first series of thermal images. The preliminary diagnosis based upon temperature standard deviation is confirmed if the same series of determinations and comparisons on the second series of thermal images yields the same cluster of six adjacent subareas.
[0046] Each of the embodiments will now be described in reference to FIGS. 7 through 10 . The first through third embodiments are illustrated by the block diagram shown in FIG. 7 . In each of the first through third embodiments, two series of IR images of the tissue are recorded in two corresponding different bands of IR wavelengths by the dual-band IR imager 112 . The two series of IR images are then converted by a converter 704 into two series of thermal images. An averager 706 then determines a series of average temperatures for each of the subareas using both series of thermal images. The averager 706 also determines an overall average temperature using both series of thermal images. All of this average temperature information is then analyzed by an analyzer 708 in the first embodiment. In the second embodiment, the two series of thermal images undergo frequency analysis, i.e., the contributing frequencies for the subareas are determined, by a frequency analyzer 710 . The contributing frequencies are then analyzed by the analyzer 708 to determine if any clusters indicate the presence of diseased tissue based upon contributing frequencies. Like the second embodiment, the third embodiment uses the frequency analyzer 710 . The third embodiment requires the analyzer to analyze the amplitude of the contributing frequencies and any clusters having unusual frequency amplitudes may be diagnosed as corresponding to diseased tissue.
[0047] The fourth and fifth embodiments are illustrated in the block diagram of FIG. 8 . As with the first three embodiments, two series of IR images of the tissue are recorded in two corresponding different bands of IR wavelengths by the dual-band IR imager 112 . The two series of IR images are then converted by the converter 704 into two series of thermal images. The averager 106 then determines a series of average temperatures for each of the subareas using both series of thermal images. The dual-band IR imager 112 also records radiance images in both bands of IR wavelengths, which are subsequently converted into thermal images. Both sets of average temperature data and the radiance image data are correlated by a correlator 722 . An analyzer 724 then analyzes the correlation data produced by the correlator 722 . In the fourth embodiment, the analyzer 724 analyzes the slope of the correlation data while in the fifth embodiment the analyzer 724 analyzes the intercept of the correlation data. FIG. 8 also illustrates an element 726 for subjecting tissue to a thermal stress. As noted above, the element 726 can create this thermal stress by directing a stream of warm or cool air over the tissue or by directing a mist at the tissue. While the element 726 is illustrated only in FIG. 8 corresponding to the apparatus for implementing the fourth and fifth embodiments, it can readily be included apparatuses for implementing the first through third and sixth through eighth embodiments.
[0048] An apparatus for implementing the sixth and seventh embodiments is illustrated in block fashion in FIG. 9 . As with the first five embodiments, two series of IR images of the tissue are recorded in two corresponding different bands of IR wavelengths by the dual-band IR imager 112 . The two series of IR images are then converted by the converter 704 into two series of thermal images. In the sixth embodiment, the two series of thermal images are then processed by the processor 744 . The processor 744 determines average temperatures and standard deviations for each of the subareas using both series of thermal images. The processor 744 then determines HST values for each of the subareas for both series of thermal images. Lastly, the processor 744 determines the average HST value for both series of thermal images. An analyzer 746 then analyzes this HST data to determine if any clusters correspond to diseased tissue. In the seventh embodiment, the two series of thermal images undergo frequency analysis by the frequency analyzer 710 . The resultant frequency analyzed data is then analyzed by the analyzer 746 to determine of diseased tissue is present.
[0049] FIG. 10 illustrates the various blocks required for implementing the eighth embodiment of the present invention. Two series of IR images of the tissue are recorded in two corresponding different bands of IR wavelengths by the dual-band IR imager 112 . The two series of IR images are then converted by a converter 704 into two series of thermal images. These two series of thermal images then undergo a series of processes by the processor 744 described above. The various averaged data is then analyzed by an analyzer 764 . In the eighth embodiment, the analyzer 764 determines if any clusters have abnormal standard deviations that would indicate the presence of diseased tissue.
[0050] The diagnostic system 110 , and in particular, the dual-band IR imager 112 will now be described in greater detail. The first and second bands of IR wavelengths detected by the dual-band IR imager 112 are preferably within the long wavelength IR (LWIR), which corresponds to radiation having a wavelength of eight to twelve microns. For example, the first band of IR wavelengths might cover the wavelength range of eight to nine microns while the second band of IR wavelengths might cover from ten to eleven microns. The LWIR is preferred as the human body IR emissions peak within this range of wavelengths. The first and second bands of IR wavelengths could alternatively be in the middle wavelength IR (MWIR) corresponding to radiation having a wavelength of three to five microns. As a further alternative, the two bands of IR wavelengths could include one in the LWIR and one in the MWIR.
[0051] The dual-band IR imager 112 may be formed in one of several ways. The dual-band IR imager 112 could include two single-band IR photodetector arrays, each sensitive to different bands of IR wavelengths. Alternatively, the two single-band IR photodetector arrays could be identical with the different bands of IR wavelength response due to filters. Using two single band IR photodetectors will require the use of a beam splitter to cause spatially registered images to be focused on each of the single-band IR photodetector arrays. While the use of two single-band IR photodetector arrays will probably decrease the cost of each single-band IR photodetector array, the overall system cost will likely increase. Such a two photodetector array-based dual-band IR imager 112 will require the aforementioned beamsplitter, and probably two separate coolers as each single-band IR photodetector array will require cooling. Such a two photodetector array-based dual-band IR imager will also require very tight tolerances to ensure that the image is truly spatially registered on both photodetector arrays, thereby reducing manufacturability.
[0052] A single dual-band IR photodetector array appears more feasible and manufacturable. Several dual-band photodetector technologies have been demonstrated including those using HgCdTe and GaAs-based multiple quantum well (MQW) semiconductor materials. Dual-band photodetectors using HgCdTe semiconductor materials have high quantum efficiencies, but place strict requirements on the HgCdTe manufacturing process. While dual-band HgCdTe photodetectors operating in the MWIR and LWIR have shown excellent performance, the use of HgCdTe semiconductor material for the preferred LWIR-LWIR configuration places extremely strict requirements on the starting HgCdTe semiconductor material. For these reasons, it appears unlikely that a commercial HgCdTe dual-band IR camera is feasible using current manufacturing technology.
[0053] GaAs-based MQW semiconductor material appears to be a more manufacturable technology and is thus preferable for the present invention. The GaAs-based starting material is commercially available from several sources and the fabrication processes are in use in a number of facilities. GaAs-based MQW semiconductor material may be fabricated into quantum well IR photodetectors (QWIPs) and enhanced QWIPs (EQWIPs). Dual-band QWIPs and EQWIPs have been demonstrated to date with the EQWIP offering better sensitivity due to its resonant optical cavity and reduced noise. Various embodiments of the EQWIP are described and claimed in U.S. Pat. Nos. 5,539,206, 6,133,571, 6,157,042, and 6,355,939 and are hereby incorporated by reference. Additional preferred embodiments of the EQWIP are described in copending application Ser. Nos. 21201 and 21301.
[0054] The present invention, by imaging a human being, encounters problems should the patient move during the image taking portion of the process. To minimize this effect, the images for the two different series of IR images are preferably taken in an alternating fashion. That is, first an IR image is taken from the first band of IR wavelengths and then an IR image is taken from the second band of IR wavelengths. By alternating the IR wavelength bands, the correlation between the first image in both series of IR images increases when compared to taking all of the first series of IR images over the course of 10 to 60 seconds and then taking all of the second series of IR images. To further minimize problems due to patient motion, the imaging rate should be relatively high, preferably in the range of 30 to 60 Hz or greater. An added benefit of the increased imaging rate is that any of the embodiments using frequency-based analysis will have increased frequency resolution.
[0055] The computer 114 within the diagnostic system 110 will be required to store significant quantities of data and undertake substantial numerical processing. The computer 114 will need to store several thousands of individual IR images and thermal images for each patient. As each of these could include 640 pixels by 480 pixels-worth of data, a rather sizeable hard disk drive and large amount of RAM will be beneficial. Due to the substantial amount of numerical processing that will be undertaken, a separate numerical processing board may be advantageous.
[0056] Although the present invention has been fully described by way of examples with reference to the accompanying drawings, it is to be noted that various changes and modifications will be apparent to those skilled in the art. Therefore, such changes and modifications should be construed as being within the scope of the invention. | A method of and apparatus for detecting diseased tissue based upon infrared imaging in two different bands of infrared wavelengths is described. The use of two series of infrared images taken in two different bands of infrared wavelengths increases sensitivity to the subtle temperature changes caused by diseased skin and tissue, especially in the case of cancerous tissue. By sensing skin temperature, the homogeneity thereof, the time variations thereof and the correlation between the two series of infrared images, the present invention decreases the rate of false positives and false negatives. The increased discrimination due to two series of infrared images allows for reliable detection of diseased or cancerous tissue even in the presence of skin tone variations such as birthmarks, tattoos and freckles. The present invention finds special application in the field of breast cancer detection where subtle skin temperature variations may readily be sensed using two series of infrared images. | 0 |
PRIORITY CLAIM
[0001] This application claims the benefit of U.S. Provisional Application No. 60/623,388, filed Oct. 29, 2004, which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Technical Field
[0003] This invention relates to digital filters and particularly to finite impulse response filters.
[0004] 2. Related Art
[0005] Digital signal processing (“DSP”) is used in a wide variety of devices, such as televisions, audio devices, hearing aids, computers and cellular phones. These devices employ DSP techniques to process signals in a variety of ways. For example, digital filtering techniques may be used to improve signal quality or to extract important information. In other cases, digital filters may be used to restore a signal that has been distorted in some way.
[0006] A digital filter, such as a finite impulse response (“FIR”) filter, typically includes a number of equally spaced taps. Each tap is separated by a delay line and is multiplied by a filter coefficient. The output of each tap is added together and passed through a reconstruction filter. The filter coefficients allow the impulse response of the filter to be specified.
[0007] FIR filters designed to operate at high sample rates often require numerous taps to properly specify waveforms and frequency responses for wide-band signals, such as audio signals. These filters often provide an excessive amount of time or frequency resolution. For example, consider a signal with a bandwidth from 50 Hz to 20 kHz. To avoid aliasing, a sample rate for the signal would typically be selected that is greater than 40 kHz. Wile this high sample rate may be necessary for the high frequency components of the signal, linear sampling across all frequencies results in excessive sampling for the low frequency components. Furthermore, the high sample rate would typically result in a FIR filter with high complexity due to numerous filter coefficients needed to specify the impulse response.
[0008] Moreover, the high complexity of FIR filters often creates obstacles to implementation. For example, selection of the suitable filter coefficients to elicit a desired frequency response can be challenging. Filter designers typically employ specialized optimization software to select suitable filter coefficients. If the desired frequency response changes, the filter designer must go through the challenging process of selecting different filter coefficients, likely employing optimization software. These optimization techniques render real-time adjustments to the filter coefficients to meet changing desired frequency responses extremely difficult and costly in terms of processing resources.
[0009] Therefore, there exists a need for a FIR filter system particularly suited for filtering non-linearly sampled input signals, with enhanced capability for real-time adjustment of the frequency response.
SUMMARY
[0010] This invention provides a filter system. The filter system may be implemented with less hardware and software resources than traditional filters.
[0011] The filter processes non-linearly sampled signals with a structure that allows the filter frequency response to be specified in fewer samples. The frequency response of the filter system may be adjusted in real-time using a gain section of the system. The gain section may include a gain element associated with the real portion of the frequency spectrum and a gain element associated with the imaginary portion of the frequency spectrum. The gain elements may be calculated by dividing each point specified in the frequency response into the real and imaginary parts. This allows the gain elements to directly specify the frequency response of the filter system.
[0012] A multi-rate filter system includes an input channel configured to receive an input signal and an output channel configured to output a filtered signal. Multi-rate filter sections are coupled between the input channel and the output channel. Each multi-rate filter section may include a downsampler with a downsampler input and a downsampler output that is connected to a subsequent multi-rate filter section. A FIR filter channel coupled to the downsampler output may also be provided in the multi-rate filter section. The FIR filter channel may include a real FIR filter interpolator and an imaginary FIR filter interpolator coupled in parallel with the real FIR filter interpolator. A real gain element coupled to the real FIR filter interpolator and an imaginary gain element coupled to the imaginary FIR filter interpolator may also be included in the FIR filter channel. The system may include a summer connected to the real and imaginary gain elements and an upsampler connected to the summer. The upsampler may include an upsampler input and an upsampler output connected to either a prior multi-rate filter section or to an output signal summer.
[0013] A filtering method includes processing an input signal through multiple series connected multi-rate filter sections. The processing in at least one of the multi-rate filter sections includes downsampling the input signal to generate a reduced rate signal. The reduced rate signal may be filtered through a real FIR filter interpolator to generate a real FIR filter interpolator output. A real weight may be applied to the real FIR filter interpolator output to generate a real weighted filter output. The reduced rate signal may also be filtered through an imaginary FIR filter interpolator to generate an imaginary FIR filter interpolator output. An imaginary weight may be applied to the imaginary FIR filter interpolator output to generate an imaginary weighted filter output. The real weighted and imaginary weighted filtered outputs may be summed to generate an FIR channel output. The FIR channel output may be upsampled to generate an increased rate signal. The reduced rate signal may be provided to a subsequent multi-rate filter section. The increased rate signal may be provided to either a prior multi-rate filter section or to a output signal summer.
[0014] In another implementation, the filter system may include an input channel configured to receive an input signal and an output channel configured to output a filtered signal. Multiple FIR filter channels that implement a filter response may be provided. Each FIR filter channel may include a filter gain element coupled to the input channel. A real FIR filter interpolator and an imaginary FIR filter interpolator may also be included in each FIR filter channel. The FIR filter channels may be coupled to the input channel and to a signal summer. The signal summer may generate the filtered signal.
[0015] Other systems, methods, features and advantages of the invention will be, or will become, apparent to one with skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features and advantages be included within this description, be within the scope of the invention, and be protected by the following claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The invention may be better understood with reference to the following drawings and description. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. Moreover, in the figures, like referenced numerals designate corresponding parts throughout the different views.
[0017] FIG. 1 is a block diagram of an example signal processing system with filter logic.
[0018] FIG. 2 is a block diagram of an example linear-sampled interpolation-in-frequency filter system.
[0019] FIG. 3 is an example time response of a cubic-spline interpolator in linear frequency.
[0020] FIG. 4 is an example of a log-sampled interpolation-in-frequency filter system.
[0021] FIG. 5 is an example of a log-sampled interpolation-in-frequency filter system.
[0022] FIG. 6 is an example time response of a cubic-spline interpolator-in-log frequency.
[0023] FIG. 7 is block diagram of an example multi-rate filter section that may be used in a multi-rate filter system.
[0024] FIG. 8 is a block diagram of an example multi-rate log-sampled, interpolation-in-log filter system.
[0025] FIG. 9 is a flow diagram of the acts which the filter system may take to process a signal in a multi-rate filter system.
[0026] FIG. 10 is a flow diagram of the acts which the filter system may take to process a signal through a multi-rate filter section.
[0027] FIG. 11 is a block diagram of an example implementation of the signal processing system shown in FIG. 1 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0028] FIG. 1 shows an example signal processing system with filter logic. The system receives an input signal from a signal source 100 . In many cases, the signal source 100 may provide a continuous signal, such as an electrical signal from a transducer. For example, where the signal source 100 provides a continuous signal, the system may sample the input signal with a continuous to discrete sampler 102 . The sampler 102 converts the continuous signal into a discrete-time signal (i.e., digital signal).
[0029] The system may include a filter logic 104 configured to filter the discrete-time signal. For example, the filter logic 104 may be configured as a low pass, high pass, bandpass or other filter. The filter logic 104 may be implemented in hardware and/or software. However, the filter logic 104 may be implemented with less hardware and software resources than traditional filters. The filter logic 104 may include discrete logic or circuitry, a mix of discrete logic and a processor which executes instructions stored in a memory, or may be distributed over multiple processors or programs. The filter logic 104 may cooperate with sample processing logic 106 which further processes the sampled input signal, for example to perform speech recognition. The sample processing logic 106 may include discrete logic, a digital signal processor (DSP), microcontroller, or other processor. The filter logic 104 may be incorporated into communication devices, sound systems, gaming devices, signal processing software, or other devices and programs. The signal out 108 may be provided to any subsequent processing system, such as a voice recognition or audio reproduction system.
[0030] FIG. 2 shows an example implementation of the filter logic 104 shown in FIG. 1 . In the example shown, an input signal 202 is sent to multiple parallel processing channels 204 . Each channel 204 includes a FIR filter section 206 and gain section 208 . The FIR filter section 206 provides an interpolation function, which may be implemented as a cubic-spline interpolator or other tone burst, for example, as discussed below with respect to FIG. 3 .
[0031] Each FIR filter section 206 includes a FIR filter interpolator 210 associated with the real portion of the frequency domain and a FIR filter interpolator 212 associated with the imaginary portion of the frequency domain. Although the FIR filter interpolators 210 and 212 have the same waveform in the example shown in FIG. 2 , the waveform is shown for example purposes only, and the waveform for FIR filter interpolator 210 may be different than the waveform for FIR filter interpolator 212 . The FIR filter interpolator 210 may be implemented with a cosine burst impulse response while the FIR filter interpolator 212 may implemented with a sine tone burst impulse response at the same frequency. Each FIR filter interpolator 210 is associated with a gain element (e.g., a r0 , a r1 , a r2 , a r3 and a r4 ) associated with the real portion of the spectrum while each FIR filter interpolator 212 is associated with a gain element (e.g., a i0 , a i1 , a r2 , a i3 and a i4 ) associated with the imaginary portion of the spectrum. A summer 214 outputs the sum of each channel 204 . As shown, the input signal 202 passes first to an initial FIR filter channel, which includes the FIR filter section 206 associated with gain elements (a r0 and a i0 ) and the summer 214 . The input signal also passes through three intermediate FIR filter channels and a final FIR filter channel.
[0032] As shown, each FIR filter's 212 impulse response is a constant-width tone burst. The frequency and phase of each burst depends on the location of the FIR filter interpolator in the complex frequency response. This form of FIR filter allows the filter's frequency response to be directly specified at a relatively small number of linear-spaced points in frequency. In the example shown, each channel is illustrated with a one second time-span FIR filter containing a 0.4 s constant-width tone burst of varying frequency. Five channels are illustrated covering a burst frequency range of 5 to 15 Hz with a step size of 2.5 Hz (=1/BurstWidth=1/0.4, the sample interval of the FIR filter). The FIR filters 212 are spaced equally in frequency at arbitrary values from ƒ 0 to ƒ n . In some examples, the frequency interval may be arbitrarily lower than the sampling frequency of the hardware on which the filter is implemented.
[0033] Each coefficient a 0 to a 4 may set the level of the corresponding tone burst associated with a particular interpolation function in frequency. To calculate the gain elements associated with each channel, the frequency points in the desired frequency response may be converted to the real and imaginary parts. For purposes of example only, consider a desired frequency response specified by the following linear-spaced frequency points: 0 dB, 0 degrees at 100 Hz, 0 dB, 90 degrees at 200 Hz, −6 dB, −60 degrees at 300 Hz, 0 dB, −45 degrees at 400 Hz and −12 dB, 45 degrees at 500 Hz. Since the frequency response is specified by five frequency points, a five channel filter system may be used. The channels weights for this example can be calculated as follows:
[0034] 1. First frequency point, 0 dB, 0 degrees at 100 Hz
[0035] Gain element associated with real portion of spectrum=10ˆ(0/20)*cos (0 degrees)=1
Gain element associated with imaginary portion of spectrum=10ˆ(0/20)*sin (0 degrees)=0
[0037] 2. Second frequency point, 0 dB, 90 degrees at 200 Hz
Gain element associated with real portion of spectrum=10ˆ(0/20)*cos (90 degrees)=0 Gain element associated with imaginary portion of spectrum=10ˆ(0/20)*sin (90 degrees)=1
[0040] 3. Third frequency point, −6 dB, 60 degrees at 300 Hz
Gain element associated with real portion of spectrum=10ˆ(−6/20)*cos (−60 degrees)=0.25 Gain element associated with imaginary portion of spectrum=10ˆ(−6/20)*sin (−60 degrees)=−0.43
[0043] 4. Fourth frequency point, 0 dB, 45 degrees at 400 Hz
Gain element associated with real portion of spectrum=10ˆ(0/20)*cos (−45 degrees)=0.71 Gain element associated with imaginary portion of spectrum=10ˆ(0/20)*sin (−45 degrees)=−0.71
[0046] 5. Fifth frequency point, −12 dB, 45 degrees at 500 Hz
Gain element associated with real portion of spectrum=10ˆ(−12/20)*cos (45 degrees)=0.18 Gain element associated with imaginary portion of spectrum=10ˆ(−12/20)*sin (45 degrees)=0.18
[0049] In contrast to a linear-sampled, interpolation-in-time filter system, a linearly-sampled, interpolation-in-frequency filter allows direct specification of the real and imaginary parts of the filter's frequency spectrum in linear frequency. With this type of filter, the frequency spectrum may be sampled much more sparsely than is typical with digital signal processing hardware. Effectively, the frequency response of the filter may be slowly varying in frequency due to the sparseness of the samples. Each linearly-interpolated sample in the filter's frequency response corresponds to a FIR filter channel whose impulse response is a tone burst at the frequency of the spectrum sample. The waveform of the burst is the inverse Fourier transform of the frequency-domain interpolation function. For linear sampling, the burst time of all the filter channels may be equal, with only the number of cycles in the burst changes.
[0050] FIG. 3 shows an example implementation of a FIR filter section's tone burst. In this example, the tone burst is a cubic-spline interpolator in linear frequency with a time response 302 and a frequency response 304 . In this example, a linear frequency scale of 0 to 2000 Hz (right) and linear time scale of −10 to +10 ms (left) is shown. The frequency sample rate in this example is 100 Hz (i.e., the interpolator steps in frequency every 100 Hz). Subpart (a) shows a 500 Hz interpolator in the real part of the spectrum. Subpart (b) illustrates a 500 Hz interpolator in the imaginary part of the spectrum. A 1,500 Hz interpolator in the real part of the spectrum is shown in subpart (c). Subpart (d) shows a 1,500 Hz interpolator in the imaginary part of the spectrum. In the example shown, the time burst width is constant, only the frequency and phase of the burst changes.
[0051] The impulse response of each channel 204 is a constant-frequency tone burst of arbitrary phase (complex) which is the time waveform corresponding to the interpolator at that specific burst frequency. The frequency of each tone burst at a particular channel is incremented at a step size which depends inversely on the duration of the burst. The tone burst is complex (real/imaginary or cosine/sine) because two FIR filter interpolators exist in the frequency domain, one for the real part of the frequency response and one for the imaginary part.
[0052] For illustration purposes, each burst is shown un-windowed. In some implementations, the actual bursts may exhibit an amplitude ramp up at the start and a ramp down at the end whose envelope shape depends on the chosen frequency-domain interpolator (as shown in the left column in FIG. 3 ). Alternately, the bursts may be formed by windowing a sine wave (of arbitrary phase) with a Tukey window which provides a half-Hann ramp-up and ramp-down to the start and end of the burst, respectively.
[0053] The linearly-sampled interpolation in frequency filter allows complex (real/imaginary or magnitude/phase) frequency responses to be directly specified in the frequency domain at linear-spaced points with far fewer samples than required by conventional FIR filters. The frequency, magnitude, and phase of the tone burst maps directly to the corresponding point in the frequency domain.
[0054] The FIR filter interpolator output is given by the following, which assumes continuous time operation:
y ( t ) = ∑ n = 0 N - 1 a n x ( t ) ⊗ [ 𝒥 - 1 ( H interp ( f 0 - n Δ f ) ) ] ( 2 )
where x(t) is the input signal, y(t) is the system output signal, N is the number of channels, the a n are the amplitude coefficients of each channel, H interp is the frequency interpolation function, ƒ 0 is the start frequency (may be an arbitrary value and need not be zero), ∇ƒ is the sample frequency interval, ℑ −1 is the inverse Fourier transform operator, and {circle around (x)} is the convolution operator.
[0055] This type of filter includes in each channel the time waveform of an inverse Fourier transformed interpolation function in frequency. In this example, the time waveforms are essentially tone bursts of constant width of varying frequency and phase. For example, a ten-channel filter may be created that allows linear specification of a 0-to-20 kHz pass-band filter's frequency response in only ten equally-spaced 2 kHz spaced samples.
[0056] FIGS. 4 and 5 show example implementations of the filter logic 104 shown in FIG. 1 . In FIG. 4 , an input signal 402 is sent to multiple parallel processing channels 404 . Each channel 404 includes a FIR filter section 406 and gain section 408 . The FIR filter section 406 provides an interpolation function, which may be implemented as a cubic-spline interpolator or other tone burst, for example, as discussed below with respect to FIG. 6 .
[0057] Each FIR filter section 406 includes a FIR filter interpolator 410 associated with the real portion of the frequency domain and a FIR filter interpolator 412 associated with the imaginary portion of the frequency domain. Although the FIR filter interpolators 410 and 412 have the same waveform in the example shown in FIG. 4 , the waveform is shown for example purposes only, and the waveform for FIR filter interpolator 410 may be different than the waveform for FIR filter interpolator 412 . The FIR filter interpolator 410 may be a cosine burst while the FIR filter interpolator 412 may be a sine tone burst of the same frequency. Each FIR filter interpolator 410 is associated with a gain element (e.g., a r0 , a r1 , a r2 , a r3 and a r4 ) associated with the real portion of the spectrum while each FIR filter interpolator 412 is associated with a gain element (e.g., a i0 , a i1 , a r2 , a i3 and a i4 ) associated with the imaginary portion of the spectrum. A summer 414 outputs the sum of each channel 404 .
[0058] The input signal 402 passes first to an initial FIR filter channel, which includes the FIR filter section 406 associated with gain elements (a r0 and a i0 ) and the summer 414 . The input signal also passes to three intermediate FIR filter channels and a final FIR filter channel. As shown, the start of the tone bursts in each FIR filter section 406 is aligned at zero.
[0059] In FIG. 5 , an input signal 502 is sent to multiple parallel processing channels 504 . Each channel 504 includes a FIR filter section 506 and gain section 508 . Each FIR filter section 506 includes a FIR filter 510 associated with the real portion of the frequency domain and a FIR filter 512 associated with the imaginary portion of the frequency domain.
[0060] Although the FIR filter interpolators 510 and 512 have the same waveform in the example shown in FIG. 5 , the waveform is shown for example purposes only, and the waveform for FIR filter interpolator 210 may be different than the waveform for FIR filter interpolator 512 . The FIR filter interpolator 510 may be a cosine burst while the FIR filter interpolator 512 may be a sine tone burst of the same frequency. Each FIR filter interpolator 510 is associated with a gain element (e.g., a r0 , a r1 , a r2 , a r3 and a r4 ) associated with the real portion of the spectrum while each FIR filter interpolator 512 is associated with a gain element (e.g., a i0 , a i1 , a r2 , a i3 and a i4 ) associated with the imaginary portion of the spectrum. A summer 514 outputs the sum of each channel 504 .
[0061] The input signal 502 passes first to an initial FIR filter channel, which includes the FIR filter section 506 associated with gain elements (a r0 and a i0 ) and the summer 514 . The input signal also passes to three intermediate FIR filter channels and a final FIR filter channel. As shown, the tone bursts for each FIR filter section 506 is aligned at their centers.
[0062] In the examples shown in FIGS. 4 and 5 , each FIR filter's impulse response is a variable-width tone burst with a constant number of cycles in each burst. The frequency and phase of each burst depends on the location of the FIR filter interpolator in the complex log frequency response. This form of FIR filter allows the filter's complex frequency response to be directly specified at a relatively small number of log-spaced points in frequency. Each channel is illustrated in the examples with a one second time-span FIR filter containing the variable-width tone burst of varying frequency. The illustrated bursts allow the log frequency response to be specified at one-tenth decade (essentially one-third octave) intervals with a sample ratio of 10 0.1 =1.2589. Five channels are illustrated with approximate log-spaced sample frequencies of 5, 6.3, 8, 10, and 12.5 Hz. The filter system may be extended to include as many channels as desired to process arbitrarily low frequencies.
[0063] The FIR filter interpolator output is given by the following equation which assumes continuous time operation:
y ( t ) = ∑ n = 0 N - 1 a n x ( t ) ⊗ [ 𝒥 - 1 ( H interp ( N e ln ( f r n f min ) ) ) ]
where x(t) is the input signal, y(t) is the system output signal, N is the number of channels, the a n are the amplitude coefficients of each channel, H interp is the interpolation function, N e is the sample density, r is the ratio between successive sample times (r=e 1/N e ), ƒ min is the sampling start frequency (ƒ min >0), ℑ −1 is the inverse Fourier transform operator, and {circle around (x)} is the convolution operator. Here the sampling stops (last frequency sample) at ƒ max =r N−1 ƒ min .
[0064] This type of FIR filter is conceptually similar to the previous linear FIR filter of FIG. 2 , but each channel includes the time waveform of an inverse Fourier transformed log-warped interpolation function in frequency. Here however, the time waveforms are tone bursts of varying width and frequency but contain a constant number of cycles. This causes the bursts to be long at low frequencies and short at high frequencies. As before, because of the complex frequency response, the burst frequency and phase changes at each channel position. Not indicated in the previous equation is an energy normalization term that keeps the energy of the tone bursts constant as their width decreases. As an example, a 20-to-20 kHz pass-band one-third-octave equalizer may be created with only 31 log-spaced channels. In this example, the frequency step ratio is equal to the tenth root often (ƒ n+1 /ƒ n =10 0.1 ).
[0065] FIG. 6 shows an example implementation of the tone burst of the FIR filter section 406 and 406 described in FIGS. 4 and 5 . This example shows the time response 602 and frequency response 604 of a cubic-spline interpolator in log frequency. In this example, the log frequency scale of 10 Hz to 10 kHz (right) and the linear time scale of −10 to +10 ms (left) is provided. The frequency sample rate shown is 10 points per decade. In other words, in the example shown, the interpolator steps in frequency every one-tenth decade (about one-third of an octave). Subpart (a) is an example with a 500 Hz interpolator in the real part of spectrum. Subpart (b) provides an example with a 500 Hz interpolator in the imaginary part of spectrum. A 2,000 Hz interpolator in the real part of spectrum is shown in subpart (c). Subpart (d) provides an example with a 2,000 Hz interpolator in the imaginary part of spectrum. The time burst width may decrease as frequency increases, but may contain the same number of cycles. In other words, the waveform of the burst may stay the same and dilate or contract as the frequency shifts.
[0066] The filter logic 104 of FIG. 1 may be implemented in a multi-rate structure. FIG. 7 shows an example of a multi-rate filter section 700 that may be implemented in such a multi-rate structure. The multi-rate filter section 700 includes a FIR filter channel 722 which includes a FIR filter section 701 and gain section 702 . A summer 704 adds the output of the gain section 702 . An upsampler 706 has an upsampler input 724 that is connected to the output of the summer 704 . An upsampler output 726 may be connected to further processing logic and/or processing circuitry and/or other logic and/or circuitry. The upsampler 706 implements upsampling of the summer output at a rate of ‘r’.
[0067] The filter section 701 may include a FIR filter interpolator 708 associated with the real portion of the frequency domain and a FIR filter interpolator 710 associated with the imaginary portion of the frequency domain. The FIR filter interpolator 708 may be a cosine tone burst while the FIR filter interpolator 710 may be a sine tone burst of the same frequency.
[0068] The gain section 702 includes the gain elements 712 and 714 . The gain element 712 associated with the FIR filter interpolator 708 corresponds with a frequency point in the real portion of the spectrum while the gain element 714 associated with FIR filter interpolator 710 corresponds with the imaginary portion of the spectrum. The gain elements 712 and 714 adjust the magnitude of the output of their respective FIR filter interpolators.
[0069] An input processing element 716 precedes the FIR filter section. The input processing element 716 may include a low pass filter 718 connected to a downsampler input 728 of a downsampler 720 . An output of the downsampler 730 is connected the filter section 701 . The downsampler 720 implements downsampling of the input signal at a rate of ‘r’.
[0070] FIG. 8 shows a multi-rate filter system 800 which may implement the filter logic 104 shown in FIG. 1 . The multi-rate filter system 800 implements multiple processing channels 802 . An input signal x in is received on an input channel 801 . Each channel includes a FIR filter section 804 and gain section 806 . Summers 808 , 810 , 812 , 814 and 816 add the output of the gain section 806 . Upsamplers 818 , 820 , 822 and 824 are connected to the output of the summers 808 , 810 , 812 , 814 and 816 . The output of the final summer 808 is the output channel y out 838 .
[0071] An input processing element 826 precedes each channel after the first channel. Each input processing element 826 may include a low pass filter 830 and a downsampler 832 . The downsamplers 832 successively implement downsampling of the input signal at a rate of ‘r’. The initial channel is not downsampled in the example shown and therefore is at the sample rate of the input signal, indicated by f s . Since the first channel is not down sampled, the first channel has the highest sample rate, indicated by HF. The subsequent channels have successively lower sample rates, which are indicated by f s /r, f s /r 2 , f s /r 3 , and f s /r 4 . As shown, the lowest sample rate is on the last channel, indicated by LF. The downsamplers 832 may be implemented in software or by integrated circuits, such as the Analog Devices AD1890, AD1891, AD1893, or AD1896 asynchronous sample rate converters.
[0072] Each channel of the filter section 804 has an impulse response that may be a complex tone burst. The complex tone burst may include a real portion and an imaginary portion of the frequency domain. Each channel includes a FIR filter interpolator 834 associated with the real portion of the frequency domain and a FIR filter interpolator 836 associated with the imaginary portion of the frequency domain. In some cases, the FIR filter interpolator 834 may be a cosine burst while the FIR filter interpolator 836 may be a sine tone burst of the same frequency. Either the real or imaginary portion of the complex tone burst may be calculated using the Hilbert-transform. In the example shown, the tone burst in the FIR filter interpolator 836 is the Hilbert-transformed 90°-phase-shifted version of the tone burst in the FIR filter interpolator 834 . In the example shown, the tone burst in the FIR filter interpolator 834 for each channel is substantially the same. In some cases, the tone bursts of FIR filter interpolator 834 on each channel may be exactly the same. Likewise, the tone burst in each FIR filter interpolator 836 may be substantially the same or in some cases exactly the same.
[0073] The gain section 806 is associated with gain elements (a r0 , a i0 ), (a r1 , a i1 ) . . . (a rN , a iN ). The gain elements may multiply the output of the real and imaginary portions of the FIR filter section 804 to adjust the amplitude of each channel. Each channel corresponds to a frequency point in the frequency response of the multi-rate filter system 800 . As examples, a frequency response specified by 5 frequency points may be implemented in a five channel filter system and a frequency response specified by 20 frequency points may be implemented with a 20 channel filter.
[0074] Each channel 802 may include two gain elements, with one gain element associated with the real FIR filter interpolator 834 and another gain element associated with the imaginary FIR filter interpolator 836 . The gain element associated with FIR filter interpolator 834 corresponds with a frequency point in the real portion of the spectrum while the gain element associated with FIR filter interpolator 836 corresponds with the imaginary portion of the spectrum. For purposes of example only, consider a desired frequency response specified by the following log-spaced frequency points: 0 dB, 0 degrees at 100 Hz, 0 dB, 90 degrees at 200 Hz, −6 dB, −60 degrees at 400 Hz, 0 dB, −45 degrees at 800 Hz and −12 dB, 45 degrees at 1.6 kHz. A five channel multi-rate filter system may implement the frequency response specified by these five spectral points. To calculate the gain elements associated with each channel, the frequency point may be converted to the real and imaginary parts. For example, the channels weights for this example may be calculated as follows:
[0075] 1. First frequency point, 0 dB, 0 degrees at 100 Hz
Gain element associated with real portion of spectrum=10ˆ(0/20)*cos (0 degrees)=1 Gain element associated with imaginary portion of spectrum=10ˆ(0/20)*sin (0 degrees)=0
[0078] 2. Second frequency point, 0 dB, 90 degrees at 200 Hz
Gain element associated with real portion of spectrum=10ˆ(0/20)*cos (90 degrees)=0 Gain element associated with imaginary portion of spectrum=10ˆ(0/20)*sin (90 degrees)=1
[0081] 3. Third frequency point, −6 dB, 60 degrees at 400 Hz
Gain element associated with real portion of spectrum=10 ˆ(−6/20)*cos (−60 degrees)=0.25 Gain element associated with imaginary portion of spectrum=10ˆ(−6/20)*sin (−60 degrees)=−0.43
[0084] 4. Fourth frequency point, 0 dB, 45 degrees at 800 Hz
Gain element associated with real portion of spectrum=10ˆ(0/20)*cos (−45 degrees)=0.71 Gain element associated with imaginary portion of spectrum=10ˆ(0/20)*sin (−45 degrees)=−0.71
[0087] 5. Fifth frequency point, −12 dB, 45 degrees at 1.6 kHz
Gain element associated with real portion of spectrum=10ˆ(−12/20)*cos (45 degrees)=0.18 Gain element associated with imaginary portion of spectrum=10ˆ(−12/20)*sin (45 degrees)=0.18
[0090] Upsamplers 818 , 820 , 822 and 824 are provided to increase the sample rate on each channel. The sample rate may be increased to match the previous channel. The Upsamplers 818 , 820 , 822 and 824 successively implement upsampling at a rate of ‘r’. As described above with respect to the downsamplers 832 , the upsamplers 818 , 820 , 822 and 824 may be implemented by integrated circuits, such as the Analog Devices AD1890, AD1891, AD1893, or AD1896 asynchronous sample rate converters.
[0091] Summers 808 , 810 , 812 , 814 , 816 and 818 are provided to sum the output of the channels. The multi-rate filter system may be extended to include as many channels as desired to process arbitrarily low frequencies.
[0092] FIG. 9 is a diagram showing the acts 900 which may be taken by the filter system 800 . Initially, the gain elements in the gain section 806 are set to implement the desired frequency response for the filter system (Act 902 ). The filter system 800 receives an input signal (Act 902 ). The filter system 800 applies the input signal to an initial FIR filter channel (Act 906 ). In addition, the filter system 800 applies the input signal to multiple parallel multi-rate filter sections 700 (Act 908 ). The output of each filter section and the initial filter channel is summed through successive sections as shown in FIG. 8 (Act 910 ). A filtered output signal ‘y’ results. The filter system 800 may then provide the filtered output signal to subsequent processing systems (Act 912 ).
[0093] FIG. 10 shows the acts which a multi-rate filter section 700 may take to process the signal received by the filter section. The filter section 700 low pass filters the input signal (Act 1002 ). The fraction of frequencies (e.g., the lower one-half or lower one-quarter of frequencies) passed by the filter may correspond to the downsampling ratios subsequently applied.
[0094] The filter section 700 reduces the sample rate associated with each of the input signal (Act 1004 ). The filter section 700 applies a real FIR filter interpolator to the reduced sample rate signal (Act 1008 ). Similarly, the filter section 700 applies an imaginary FIR filter interpolator to the reduced sample rate signal (Act 1010 ).
[0095] The filter section 700 also applies a real filter gain to the output of the real FIR filter interpolator (Act 1012 ). An imaginary filter gain is also applied to the output of the imaginary FIR filter interpolator (Act 1014 ). The real gain and the imaginary gain may be directly set to specify the frequency response of the filter system 800 .
[0096] After the real and imaginary gains are applied, the filter section 700 sums the outputs of the real and imaginary FIR filter interpolators (e.g., using the summer 704 ) (Act 1016 ). The filter section 700 then upsamples the summed output (Act 1018 ). For example, the filter section 700 may upsample the summed output to match the sample rate of a prior filter section. The filter section 700 then provides the upsampled signal to the prior filter section or the initial filter channel.
[0097] FIG. 11 shows an example implementation 1100 of the filter logic 104 . In this example, the system includes a processor 1102 connected to memory 1104 . The processor 1102 may be any processor capable of executing machine readable instructions, such as a digital signal processor (“DSP”), microcontroller or other processor. The memory 1104 may be any machine readable medium, such as a disk, EPROM, flash card or other memory.
[0098] The memory 1104 may include a filter program 1106 which the processor 1102 executes. The filter 1106 may implement low-pass filtering, upsampling, downsampling, application of the real and imaginary FIR filter interpolators, signal summing, or any other processing act noted above. The memory 1104 may also store operational parameters for the filter system. For example, the memory 1104 may store real and imaginary FIR filter interpolator gains 1108 , the interpolator impulse responses 1110 , or any other parameters. The processor 1102 may change the parameters on the fly to reconfigure the filter system to operate according to any currently desired frequency response.
[0099] The processor 1102 is configured to receive an input signal. In some implementations the input signal may be received as digital data (e.g., as digital samples of a continuous time input signal). In other implementations, the processor 1102 may be communicate with an analog-to-digital converter which converts an analog input signal into digital data (e.g., at a non-linear sample rate). Upon receiving the input signal, the processor 1102 may execute the filter program 1106 to filter the input signal as desired.
[0100] The filter program 1106 may include instructions for processing the signal using any filtering implementation described above. In a multi-rate implementation, for example, the upsampling and/or downsampling may be performed by the processor 1102 executing instructions in the filter program 1106 . An output signal, which has been processed according to the filter program 1106 , may be provided as an output of the processor 1102 .
[0101] The processor 1102 may also connect with post processing logic 1112 . The post-processing logic 1112 may include, as examples, an audio reproduction system 1118 , digital and/or analog data transmission systems 1114 , or a voice recognition system 1116 . The processor 1102 may provide the filtered output signal to any other type of post-processing logic.
[0102] The voice recognition system 1116 may include circuitry and/or logic that interprets, takes direction from, records, or otherwise processes voice. The voice recognition system 1116 may be process voice as part of a handsfree car phone, desktop or portable computer system, entertainment device, or any other system. In a handsfree car phone, the processor 1102 may be used in conjunction with the filter program 1106 to remove echo noise or otherwise remove undesired signal components in the output signal delivered to the voice recognition system 1116 .
[0103] The transmission system 1114 may provide a network connection, digital or analog transmitter, or other transmission circuitry and/or logic. The transmission system 1114 may communicate filtered signals generated by the processor 1102 to other devices. In a car phone, for example, the transmission system 1114 may communicate filter signals from the car phone to a base station or other receiver through a wireless connection such as a ZigBee, Mobile-Fi, Ultrawideband, Wi-fi, or a WiMax network.
[0104] The audio reproduction system 1118 may include digital to analog converters, filters, amplifiers, and other circuitry or logic. The audio reproduction system 1118 may be a speech and/or music reproduction system. The audio reproduction system 1118 may be implemented in a cellular phone, car phone, digital media player/recorder, radio, stereo, portable gaming device, or other devices employing sound reproduction.
[0105] While various embodiments of the invention have been described, it will be apparent to those of ordinary skill in the art that many more embodiments and implementations are possible within the scope of the invention. Accordingly, the invention is not to be restricted except in light of the attached claims and their equivalents. | This invention provides a filter system which may be implemented with less hardware and software resources than traditional filters. In addition, the filter system structure reduces the complexities typically associated with filter design by permitting direct specification of the filter frequency response. Thus, the filter system may adaptively change the filter frequency response on the fly without incurring excessive time or computational costs. The filter system may provide a filtered signal output to any subsequent processing system, such as a voice recognition system or audio reproduction system. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a waveguide band reject filter employing TEM coaxial type resonators that partially protrude into the top wall of the waveguide in such a way as to produce a predetermined frequency selective discontinuity. By proper choice of location, number of resonators, resonator configuration and protrusion, a spurious free highly efficient frequency selective band reject filter response can be obtained.
2. Description of the Prior Art
Microwave filters are used to provide frequency selectivity, that is, to pass certain frequencies and reject others by means of a group of reactive circuit elements. The prior art of specific interest in this case involves band reject filters that are designed to eliminate a specific frequency band within a much larger spectrum.
Band reject filters may be designed using various techniques that employ, for example, lumped elements with discrete coils and capacitors, stripline, coaxial resonators or waveguide resonators. The present invention to be described operates in a waveguide system, so the discussion of prior art will be confined to waveguide band reject filters.
A waveguide band reject filter consists of a section of waveguide having a direct path from input to output. Individual waveguide resonant cavities are then mounted on the waveguide section and connected to it through iris openings in the waveguide section. FIGS. 1A and 1B illustrate a three resonator waveguide band reject filter where the waveguide resonant cavities are mounted on the broad wall of the main waveguide and coupled to it through iris slots to produce the proper frequency selective discontinuity. FIG. 2 presents the response of this filter showing a rejection notch of greater than 50 dB.
A similar response can also be obtained when double ridge waveguide is used between the input to output ports. The coupling from the rejection resonator to the main guide is obtained by moving the iris coupling slot off center so that it is adjacent to the ridge, i.e., between the ridge and the side wall. The reject resonators are still mounted as shown in FIGS. 1A and B.
Both the standard waveguide and ridge waveguide filters described are very efficient and serve a purpose. However, the resonant waveguide cavities, common to both designs, have a second spurious response that will occur at less than twice the fundamental resonant frequency as shown in FIG. 2. This is explained and expected because the fundamental resonance occurs at a frequency where the waveguide wavelength is 1/2 wavelength long and the next resonance occurs at a frequency where the waveguide wavelength is one wavelength long.
The wavelength in the waveguide is not a linear function since it approaches infinity when the resonant frequency approaches the cut-off frequency of the waveguide. Thus, the relationship between the first and second resonance in the waveguide can be, say 1.7 to 1 rather the 2.0 to 1. In any case, a second rejection response will occur at somewhat less than twice the desired first response frequency.
In many cases where a reject filter is needed, the added spurious response is of no significance. This is especially true when the spurious rejection falls outside the range of the waveguide. However, where a broad frequency spectrum is required, such as that obtained with ridge waveguide, the spurious rejection notch can fall within the desired pass band. For example, the pass band of a particular ridge waveguide may be 6.5 GHz to 18.0 GHz. Thus, with a notch frequency set at 9.0 GHz, the undesired spurious notch will occur at 15.5 GHz and produce undesired attenuation at that frequency.
The object of this invention is to provide a waveguide band reject filter that has no spurious response occurring within the waveguide frequency range.
SUMMARY OF THE INVENTION
The new waveguide band reject filter, the subject of this invention, employs a coaxial type resonator that provides spurious free performance over the entire ridge waveguide frequency band. The resonator partially protrudes (by the proper amount) into the ridge waveguide through an off-set opening to obtain the desired coupling to the signal passing through the waveguide.
The coaxial resonator is capacitively loaded where it passes through the waveguide opening and additionally loaded with a small "hat" on the end of the resonator.
The fundamental resonance of a grounded coaxial resonator of the present type will occur at one-quarter wavelength and its next spurious response will occur at three-quarter wavelength i.e., three times the desired notch frequency rather than only twice as was discussed for the case of the waveguide cavity resonators. The coaxial capacitive loading described above, further improves this relationship so that the first spurious response occurs at approximately 3.5 times the desired notch frequency.
Thus, no spurious response will occur in a ridge waveguide band reject filter employing coaxial resonators of the present invention when tuned to any frequency in its operating band (e.g. 6.5 GHz 18.0 GHz).
BRIEF DESCRIPTION OF THE DRAWINGS
A detailed description of the invention will be made with reference to the accompanying drawings wherein like numerals designate corresponding parts in the several figures.
FIGS. 1A and 1B show the mechanical layout and dimensions for a standard waveguide band reject filter having three resonators coupled to the main inputoutput waveguide via small iris slots in the top wall of the waveguide. The tuning screws mounted in the waveguide resonant cavities are used to synchronous tune the three cavities to the desired rejection frequency.
FIG. 2 illustrates the response of the band reject filter described in FIG. 1. It should be noted that the undesired second rejection occurs at approximately 15.5 GHz with the desired rejection band occurring at 9.0 GHz, in this example.
FIGS. 3A, 3B and 3C provide a mechanical layout of the new invention employing eight coaxial resonators where the coaxial resonators are mounted as shown in the cut-away. Tuning is accomplished by adjusting the length of the coaxial element that protrudes through the waveguide wall opening. FIG. 3A is a side view, FIG. 3B is a top view and FIG. 3C is a cross-sectional view (along the line 3C--3C of FIG. 3B) of a typical embodiment of the invention.
FIGS. 4A and 4B provide a more detailed view (not to scale) of the coaxial resonator and its relationship to the waveguide structure. Note the coaxial cavity outside the waveguide, also the resonator protrusion through the waveguide and the loading "hat" on the end of the resonator.
FIGS. 5 through 9 provide measurement data of the new ridge waveguide band reject filter with the coaxial resonators tuned to 9.4 GHz.
FIG. 5 is the measured insertion loss of the filter across the band 6.7 GHz to 18.1 GHz. This measurement shows that spurious free performance is obtained and that the insertion loss is very low outside of the desired stop band.
FIG. 6 provides additional insertion loss detail in the immediate region of the stop band.
FIG. 7 shows detail of the depth and width of the notch, i.e., the 60 dB bandwidth is 0.22 GHz wide with the depth extending to greater than 80 dB.
FIG. 8 illustrates measurement data regarding the return loss in the immediate region adjacent the stop band. A return loss of 14 dB is equivalent to a VSWR of 1.5 to 1.
FIG. 9 shows the return loss of the complete band of interest that further confirms the response of FIG. 5 showing that there are no spurious responses below the upper band of interest, i.e., 18.1 GHz.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following detailed description is of the best presently contemplated modes of carrying out the invention. This description is not to be taken in a limiting sense, but is made merely for the purpose of illustration of the general principles of the invention since the scope of the invention is best defined by the appended claims.
Non-ridged waveguide used from many applications has a limited frequency range of operation. For example, X-band WR-90 waveguide has a good operating frequency range of 8.0 to 12.4 GHz. Its upper frequency range of operation is limited because the second mode (undesired) can occur at 13.4 GHz where its use is not possible.
Single and double ridge waveguide was then developed to improve the operating frequency range of waveguide. By placing a ridge of the proper dimensions in the center of the guide, the low frequency cut-off can be lowered because of the capacitive loading effect and the upper range is also increased since the second resonance is moved higher by the presence and location of the capacitive loading.
With the general use of ridge waveguide for high power aircraft radar systems, the undesired spurious response produced by the filter described in FIGS. 1A and 1B and illustrated in FIG. 2 is often unacceptable. An alternate solution would be to use a strip-line or coaxial reject filter (coaxial input and output connectors). If waveguide input and output is required, then transitions to waveguide could be employed. However, if the later approach is taken, it will result in a relatively large insertion loss in the desired bands which is most often not acceptable. The structure is also generally very power limited.
The invention, as shown in FIGS. 3A, B, C and 4A, B, employs ridge waveguide that may be inserted directly in the wave guide run between the radar transmitter/receiver and the antenna. The insertion loss, as shown in FIG. 5, is typically 0.2 dB over much of the band, a very low value. Likewise the other performance features as shown in FIGS. 6 through 9 are very compatible with radar systems.
A mechanical description of an illustrative embodiment of the invention is as follows. The waveguide reject filter 10 is housed (FIGS. 3A and 3B) in a section of ridge waveguide 11 having flanges 12 on either end. Top and bottom ridges 13 provide the loading previously discussed.
In the embodiment of FIGS. 3A and 3B, eight resonators 14 are employed. However, the number of such resonators is a design choice, and the invention will work with even a single resonator. In general, the depth and width (i.e., the attenuation and bandwidth) of the desired rejection band will be determined by how many resonators are employed.
For ease of fabrication, in the illustrated embodiment the resonators 14 are situated alternately on opposite sides of the ridge 13. However, each such resonator will be effective regardless of which side of ridge it is located at. Advantageously, but not necessarily, successive such resonators are spaced (with respect to the longitudinal axis of the waveguide) by about one-quarter wavelength of the reject frequency. This is indicated in FIG. 3B. Thus in this embodiment there are eight resonators 14, effectively spaced along the axis of the waveguide 11 at intervals of one-quarter wavelength.
Each resonator 14 comprises a hollow cylindrical cavity 15. In the embodiment of FIGS. 3A-3C, this cavity 15 is partly milled into the waveguide 11 itself, and partly milled into a rectangular block 16 that is fastened to the top of waveguide 11 by appropriate bolts 17. While such construction is convenient, the invention is not limited to this particular manner of fabricating the resonator cavity.
Each coaxial resonator 14 includes a rod-like coaxial element 18 which extends through the cavity 15 and through an opening 19 in the top wall 11a of the waveguide 11. The bottom end of the element 18 is provided with a cap or capacitive loading hat 18a situated within the waveguide 11. The upper end 18b of the coaxial element 18 is threaded for mounting within a corresponding threaded hole at the top of the block 16. The end 18b is slotted to permit adjustment of the distance which the hat 18a protrudes into the waveguide 11. The element 18 is locked in place by a nut 20.
The frequency of the coaxial resonator 14 is determined by various dimensions including the diameter of the cavity 15, the diameters of the coaxial element 18 and the hat 18a, the size of the opening 19, and the amount of protrusion of the coaxial element 18 into the waveguide 11. Such protrusion distance can be adjusted by rotating the threaded end 18b of the coaxial element 18, thereby facilitating easy fine tuning of the reject filter. The amount of protrusion also has an effect on the bandwidth, i.e., on the width of the rejection notch. In general, the further the protrusion of the hat 18a into the waveguide 11, the wider will be the notch.
Advantageously, but not necessarily, the ratio between the inside diameter of the cavity 15 and the diameter of the coaxial element 18 is about 3:1 or 4:1.
FIG. 3C shows typical dimensions for a waveguide band reject filter in accordance with the present invention, and designed for operation in the 6.5 GHz to 18 GHz range, with a nominal reject frequency of 9.4 GHz. This rejection frequency typically can be adjusted in the range of say 9.3 GHz to 9.5 GHz by varying the protrusion distance of the coaxial element 18 by turning the threaded end 18b thereof.
Within the waveguide 11, each resonator 14 essentially "looks like" a short circuit to a wave at the reject frequency which is propagating down the waveguide 11. In effect, the energy of such wave is reflected back toward the source as a result of the presence of the coaxial resonator.
Minor adjustments to improve the return loss are sometimes needed. This is accomplished using threaded adjustment screws 21 projecting through the ridge 13 into the waveguide 11.
In an alternative embodiment (not shown), solenoids or other mechanical arrangement may be provided to pull the coaxial elements 18 upward so that they do not protrude into the waveguide 11. When so withdrawn, the reject filter 14 is ineffective. In other words, the reject filter 14 can be switched into and out of the circuit by selectively withdrawing or reinserting the coaxial element 18 into a protruding relationship within the waveguide 11. | The present invention relates to a waveguide band reject filter employing TEM coaxial type resonators that partially protrude into the top wall of the waveguide in such a way as to produce a predetermined frequency selective discontinuity. By proper choice of location, number of resonators, resonator configuration and protrusion, a spurious free highly efficient frequency selective band reject filter response can be obtained. | 7 |
FIELD OF THE INVENTION
[0001] The present invention relates to a two-phase composition. One phase of the composition is hydro-alcoholic, and the other phase is an oil phase. When utilized as a mouth rinse, the composition desorbs bacteria from the teeth and other surfaces of the mouth and provides anti-microbial properties to the mouth.
[0002] The primary use for the composition of the present invention is in oral hygiene. Compositions of the invention can also be used in entirely different applications, where anti-microbial and bacterial desorption actions are desired.
BACKGROUND OF THE INVENTION
[0003] Tooth decay and periodontal disease are due to bacterial accumulations on the surfaces of the teeth in the form of a macroscopic layer generally referred to as dental plaque. Dental plaque firmly adheres to the surface of teeth, and is composed of about 70% bacteria, about 20% polysaccharides produced by the bacteria and about 10% food remains. It is generally known that acids stored in dental plaque decalcify enamel, causing dental caries. The generation of dental caries is also linked to the presence of certain types of bacteria on the surfaces of teeth. Halitosis, generally referred to as bad breath, has been attributed to the presence and activity of bacteria in the oral cavity. Swollen gums, generally referred to as gingivitis, occurs when the bacteria in dental plaque causes the gums to become inflamed. In the mildest form of gingivitis the gums redden, swell and bleed easily. Accordingly, decreasing the amount of bacteria in the mouth in a fast and efficient way is desired in order to maintain fresh breath for a longer period of time and to prevent dental caries and gingivitis.
[0004] Mouth rinses are commonly utilized to freshen the breath and kill bacteria. Alcohol is typically utilized as the antimicrobial agent in a mouth rinse. However, alcohol can be damaging or irritating to oral tissues. If alcohol were to be used, it would be desirable to use lower levels of alcohol.
[0005] The desire for a liquid composition that offers long-lasting fresh breath in a mouth rinse without having oral tissue damage or irritation due to the presence of alcohol has led to the development of two-phase liquid compositions.
[0006] In U.S. Pat. No. 6,465,521, Rosenberg discloses a composition for desorbing bacteria from surfaces of the teeth. Rosenberg's invention uses a two-phase preparation of oil and water, which upon shaking forms a temporary oil-in-water emulsion. Unlike the present invention, Rosenberg's invention does not include a hydro-alcoholic phase that offers faster and more efficient anti-microbial activity with desired plaque desorption features.
SUMMARY OF THE INVENTION
[0007] In accordance with this invention, there is provided a two-phase composition which upon shaking forms an emulsion, comprising:
[0000] a.) a hydro-alcholic phase; b.) an oil phase having a Hildebrand solubility parameter of from about 1 to about 7.5; and c.) a cationic surface active agent.
[0008] The invention will be more fully understood and further advantages will become apparent when reference is made to the following detailed description.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0009] The two-phase composition of the present invention includes from about 50% to about 98% by weight, based on the total weight of the composition, of a hydro-alcohol phase. As used herein, hydro-alcohol phase means a mixture comprising water and ethyl alcohol. The amount of ethyl alcohol in the two-phase composition may range from about 2% to about 50%, preferably from about 5% to about 20%, more preferably from about 8% to about 12%, by weight, based on the total weight of the composition. The ethanol used in the practice of the present invention must be of a grade that is safe for oral use.
[0010] The amount of water in the two-phase composition may range from about 48% to about 96%, preferably from about 60% to about 95%, more preferably from about 80% to about 90%, by weight, based on the total weight of the composition.
[0011] The two-phase composition of the present invention further includes an oil phase having a Hildebrand solubility parameter of from about 1 to about 7.5. The amount of the oil phase may range from about 2% to about 50%, preferably from about 5% to about 30%, more preferably from about 10% to about 20%, by weight, based on the total weight of the composition. Suitable oils for use in the oil phase of the present invention include, but are not limited to, olive oil, corn oil, coconut oil, soybean oil, safflower oil, mineral oil, grapeseed oil, canola oil, sesame seed oil, cottonseed oil, polydecene and mixtures thereof. Other materials that are not soluble in water, including, but not limited to, lower alkyl esters of longer chain fatty acids, e.g., isopropyl palmitate, isopropyl myristate and mixtures thereof may be included in the oil phase, as long as the Hildebrand solubility parameter for the entire oil phase is from about 1 to about 7.5.
[0012] The compositions of the present invention also include at least one cationic surface active agent. The amount of cationic surface active agent may range from about 0.001% to about 5%, preferably from about 0.01% to about 0.1% by weight, based on the total weight of the composition. Suitable cationic surface active agents include, but are not limited to, pyridinium-based cationic surface-active molecules, such as cetylpyridinium chloride and laurylpyridinium chloride; chlorhexidine, chlorhexidine diacetate, chlorhexidine digluconate, and chlorhexidine dihydrochloride; monalkyl quaternary ammonium compounds, such as benzalkonium chloride, cetalkonium chloride, cetalkonium bromide, lauralkonium chloride, lauralkonium bromide, soytrimonium chloride, and polyethylene glycol-5-stearyl ammonium lactate; dialkyl quaternary ammonium compounds, such as dilauryl dimonium chloride, dicetyl dimonium chloride, dicetyl dimonium bromide, desqualinium chloride, and soyamido propyl benzyldimonium chloride; quaterniums, such as Quaternium 15 and polyquaterniums; amine fluorides; cationic polysaccharides, such as chitosan and its derivatives; and cationic polypeptides, such as poly L-lysine, poly D-lysine, and lysozyme.
[0013] Two-phase compositions are taught in U.S. Pat. No. 6,465,521, the disclosure of which is hereby incorporated by reference in its entirety. The two-phase compositions of the '521 patent and of the present invention form an emulsion upon shaking.
[0014] The emulsion formed by shaking the two-phase composition of the present invention is swished around in the mouth of the user, thereby removing plaque from the teeth and killing bacteria in the mouth. The emulsion separates (or “breaks”) back into a two-phase composition relatively quickly. The time it takes for the emulsion to break depends on the components of the two-phase composition and relative amounts thereof. Generally, the emulsion breaks within from about 30 seconds to about 30 minutes after shaking or agitation has stopped.
[0015] As is known in the art, commercially available colorants, flavorants, thickeners, and preservatives may be included in either or both of the phases of the two-phase compositions of the present invention in amounts known to those of ordinary skill in the art.
[0016] The compositions of the present invention may further include surfactants. Suitable surfactants include nonionic and amphoteric surfactants.
[0017] Nonlimiting examples of nonionic surfactants include those selected from the group consisting of alkyl glucosides, alkyl polyglucosides, polyhydroxy fatty acid amides, alkoxylated fatty acid esters, sucrose esters, amine oxides, and mixtures thereof. Specific examples include, but are not limited to, nonionic surfactants selected from the group consisting of C8-C14 glucose amides, C8-C14 alkyl polyglucosides, sucrose cocoate, sucrose laurate, lauramine oxide, cocoamine oxide, and mixtures thereof.
[0018] Nonlimiting examples of amphoteric surfactants (which also includes zwitterionic surfactants) are those selected from the group consisting of betaines, sultaines, hydroxysultaines, alkyliminoacetates, iminodialkanoates, aminoalkanoates, and mixtures thereof.
[0019] Nonlimiting examples amphoteric surfactants useful in the practice of the present invention include disodium lauroamphodiacetate, sodium lauroamphoacetate, cetyl dimethyl betaine, cocoamidopropyl betaine, cocoamidopropyl hydroxy sultaine, and mixtures thereof.
[0020] Several Examples are set forth below. The claims should not be considered as being limited to the details thereof.
EXAMPLE 1
Two-Phase Compostion without Ethanol
[0021] The materials listed in Table 1 below were combined to provide a two-phase mouthwash composition without ethanol, similar to the Rosenberg '521 patent.
TABLE 1 Water 84.1221 Ethanol 0 Sorbitol 0.5 Sodium Saccharin 0.15 Monosodium Phosphate 0.05 Cetylpyridinium Chloride 0.05 Sodium Methylparaben 0.05 Disodium EDTA 0.05 Citric Acid 0.0167 FD&C Blue #1 0.00018 D&C Yellow 10 0.00105 Isopropyl Myristate 14.81 Mint Flavor 0.2 Total 100.00
[0022] The Hildebrand Solubility Parameter (“HSP”) of the oil phase of Example 1 (the only component of which is isopropyl myristate) was 7.78.
[0023] The formulations of Example 1 and the following Examples herein were evaluated following the standard time-kill test protocol described below. Formulations that demonstrated at least a 2-log reduction of bacteria in 30 seconds with about 10% alcohol were considered to be acceptable.
[0000] Materials
[0000]
Fresh broth culture of Fusobacterium nucleatum. ATCC 25586
Deionized water (sterile)
9 mL Trypticase Soy broth+25% Capitol IV Broth
Bulk agar prepared: Brain-Heart Infusion agar
Sterile disposable Petri dishes (100×15 mm)
Sterile disposable pipets
Waterbath (40° C.±2° C.)
Stopwatch (or equivalent)
Vortex mixer
Incubator at 35° C. (±2° C.)
0.85% Saline (or equivalent)
Anaerobic Chamber
[0036] A sterile deionized water control was prepared separately and tested for test validation purposes. Undiluted test samples were vortexed to combine the two phases in the mouthrinse prior to inoculation of the test organisms. Test and control samples were inoculated with inoculum suspensions to yield 10 5 -10 6 CFU/mL at a ratio of 1:100 (V/W). The test samples were vortexed for 30 seconds, then 1 mL aliquots were transferred from the test and control samples to 9 mL of Broth to neutralize antimicrobial activity (ie. 1:10 dilution in neutralized broth). Serial dilutions were prepared and the total plate count of each aliquot was determined. Pour plating for a total count was conducted using an agar and incubation temperature which readily supported test microorganism growth. Total plate counts of the test formulation and control sample were compared at the 30 second time interval to determine the microbiocidal activity of the test formulation. Results are reported as microbial log reduction exhibited by the test formulation as compared to the control sample.
[0037] The Example 1 formulation exhibited 0.8-log reduction (microbial kill) at 60 seconds. In a 30 second time kill test, the example 1 formulation exhibited a 0.0-log reduction. In an attempt to achieve rapid kill, alcohol based samples were prepared at two different concentrations as shown in Example 2 and 3 below.
EXAMPLE 2
Two-Phase Composition with 5% Ethanol
[0038] The materials listed in Table 2 below were combined to form the two-phase mouthwash composition of Example 2.
TABLE 2 Water 79.1221 Ethanol 5 Sorbitol 0.5 Sodium Saccharin 0.15 Monosodium Phosphate 0.05 Cetylpyridinium Chloride 0.05 Sodium Methylparaben 0.05 Disodium EDTA 0.05 Citric Acid 0.0167 FD&C Blue #1 0.00018 D&C Yellow 10 0.00105 Peppermint Oil #35 1.5 Isopropyl Myristate 13.51 Total 100.00 HSP = 7.78
EXAMPLE 3
Two-Phase Composition with 10% Ethanol
[0039] The materials listed in Table 3 below were combined to form the two-phase mouthwash composition of Example 3.
TABLE 3 Water 74.1221 Ethanol 10 Sorbitol 0.5 Sodium Saccharin 0.15 Monosodium Phosphate 0.05 Cetylpyridinium Chloride 0.05 Sodium Methylparaben 0.05 Disodium EDTA 0.05 Citric Acid 0.0167 FD&C Blue #1 0.00018 D&C Yellow 10 0.00105 Isopropyl Myristate 13.51 Peppermint Oil 1.5 Total 100.00 HSP = 7.78
EXAMPLE 4
Two-Phase Composition with 14% Ethanol
[0040] The materials listed in Table 4 below were combined to provide the two-phase mouthwash composition of Example 4.
TABLE 4 Water 70.1221 Ethanol 14 Sorbitol 0.5 Sodium Saccharin 0.15 Monosodium Phosphate 0.05 Cetylpyridinium Chloride 0.05 Sodium Methylparaben 0.05 Disodium EDTA 0.05 Citric Acid 0.0167 FD&C Blue #1 0.00018 D&C Yellow 10 0.00105 Isopropyl Myristate 14.87 SymriseMint 825555 0.14 Total 100.00 HSP = 7.78
[0041] The above composition provided an approximately 3.6 log reduction in bacteria. Though the two-phase formulations of Examples 2 and 3 contained ethanol at 5% and 10% respectively, they did not demonstrate a 2-log reduction in bacteria. Since isopropyl myristate is soluble in ethanol, it was hypothesized that possibly the alcohol was solubilizing the oil phase components, and thus not sufficiently getting exposed to microorganisms to achieve immediate antimicrobial activity. However, a composition with 14% alcohol may burn or irritate the oral mucosa; therefore it was desired to have the same micro kill efficacy at lower alcohol levels.
[0042] In order to test the hypothesis, an oil less soluble with ethanol, mineral oil, was substituted for isopropyl myristate and the alcohol level was reduced to 10%. The resulting two-phase composition was tested for its antimicrobial efficacy. See Example 5.
EXAMPLE 5
Two-phase Composition with 15% Mineral Oil and 10% Ethanol
[0043] The materials listed in Table 5 below were combined to provide the two-phase mouthwash composition of Example 5.
TABLE 5 Water 74.114 Ethanol 10 Sorbitol 0.5 Sodium Saccharin 0.15 Cetylpyridinium Chloride 0.05 Sodium Methylparaben 0.05 Disodium EDTA 0.05 Citric Acid 0.07 Benzoic Acid 0.005 FD&C Blue #1 0.0001 D&C Yellow 10 0.00105 Mineral Oil #35 15.01 Total 100.00 HSP = 7.09
[0044] The two-phase composition of Example 5 demonstrated a 4.2 log reduction in bacteria.
EXAMPLE 6
Two-Phase Composition with 15% Oil Blend and 10% Ethanol
[0045] Example 6—The two-phase composition of this Example 6 was the same as that of Example 5 except the 15.01 parts of mineral oil in Example 5 was replaced by an equal amount of a 50/50 (wt %) blend of isopropyl myristate and mineral oil. The HSP of the oil phase of this Example 6 was 7.44. Upon testing in the manner set forth for the earlier Examples, the two-phase composition of Example 6 demonstrated a 4.1 log reduction in bacteria.
TABLE 6 Water 73.40385 Ethanol 10 Sorbitol 0.5 Sodium Saccharin 0.15 Cetylpyridinium Chloride 0.05 Disodium EDTA 0.1 Citric Acid 0.04 Benzoic Acid 0.005 FD&C Blue #1 0.0001 D&C Yellow 10 0.00105 Mineral Oil #35 7.5 Isopropyl Myristate 7.5 Flavor 0.75 Total 100.00 HSP = 7.44
[0046] Table 7 shown below summarizes each example by showing the log-reduction of each formulation, as well as the percentage of alcohol used.
TABLE 7 30 Second Example # Alcohol % HSP Log Reduction 1 0 7.78 0.0 2 5 7.78 0.9 3 10 7.78 0.9 4 14 7.78 3.6 5 10 7.09 4.2 6 10 7.44 4.1 | The present invention relates to a two-phase composition that provides anti-microbial action and desorbs bacteria from solid surfaces and from living tissues, and in particular breath freshening and plaque removal. The composition provides fast and persistent anti-microbial activity and includes a hydro-alcoholic phase, an oil phase, and a cationic surface active agent. | 0 |
BACKGROUND OF THE INVENTION
The present invention relates to medical devices, and more particularly, to an improved programmable infusion pump for delivering intravenous drugs at a controlled rate to a patient.
It is often necessary to intravenously supply patients with pharmaceutically active liquids over a long period of time at a controlled rate. It is desirable that this be accomplished while the patient is in an ambulatory state.
The prior art includes devices that employ a bag filled with fluid medication that feeds by gravity through IV tubing having drip or other controllers. It is difficult for a patient to be ambulatory with a gravity fed infusion device. In addition, flow control in this type of device is very limited.
Another prior art infusion apparatus comprises an elastic bladder forming a liquid container, an elongated cylindrical housing enclosing the bladder, a flow control valve, and tubing for supply of the liquid to the patient. The elastic walls of the bladder expand along the walls of the cylindrical housing when filled with the liquid, and provide the pressure for expelling the liquid. The bladder is typically filled by hand with a syringe which often requires an inordinate amount of force. Another drawback is that the bladder is forced to expand into an unnatural elongated configuration along the housing walls as it is filled. As a result of this unnatural configuration, the pressure of the bladder varies widely with the volume of liquid therein. Therefore, in most cases, this type of elastic infusion apparatus does not have a reasonably stable pressure and flow rate over the infusion period. Most of such devices either have a flow rate that decreases with pressure, which decreases with volume, or one that remains roughly constant until the end where it surges. Attempts have been made to control pressure and flow rates by means of complicated and expensive flow control valves and devices. Other approaches have utilized exotic and expensive elastic materials in an effort to control the pressures and flow rates.
Another type of infusion apparatus uses pressurized gas as the driving force for the intravenous liquid. In such systems there may be hydraulic feedback through the pneumatic source in order to precisely regulate hydraulic pressure. See for example U.S. Pat. Nos. 4,430,078 of Sprague, 4,335,835 of Beigler et al., and 4,327,724 of Birk et al. Such pneumatically driven infusion devices tend to have reducing flow rates and pressures as the stored pressurized gas source is exhausted.
Still another type of infusion apparatus employs a peristaltic or other positive displacement pump which is electrically driven. Programmable infusion pumps have been provided having the capability for precise tailoring of the fluid delivery rate parameters in different modes, such as, continuous, intermittent, PCA (patient controlled analgesic) and TPN (total parenteral nutrition). Originally, such programmable infusion pumps were large and not well suited for ambulatory patients. They used complex and expensive replacement pump cartridges to maintain sterility.
More recently, small programmable infusion pumps have been available with disposable plastic cartridges that engage a peristaltic pump. However, such cartridges have been bulky and expensive and have required excessive drive power in the pumps, leading to rapid battery drain. Another drawback of these existing programmable infusion systems of this type is that they are complicated and very expensive to manufacture and to maintain.
There is an ever increasing desire in the health care field to get patients out of expensive hospital care environments and back to their homes. Many such patients require intravenously administered medications, but are unable to program existing programmable infusion systems themselves, and trained operators cannot economically visit their homes. In addition, many such patients are unable to change the delivery rates in accordance with subsequent physician prescriptions. Furthermore, they cannot effectively verify the prescribed delivery parameters.
Accordingly, it would be desirable to provide an improved low cost single channel programmable infusion system for delivering intravenous drugs at a controlled rate to an ambulatory patient that can be more easily programmed by a patient, and which will allow patient verification of the prescribed delivery parameters.
SUMMARY OF THE INVENTION
It is, therefore, the primary object of the present invention to provide an improved low cost programmable infusion pump for an ambulatory patient, which enables intravenous fluid delivery parameters to be readily programmed and verified by the patent.
Our invention comprises a programmable infusion system, which includes a disposable IV tubing apparatus for conveying intravenous fluid from a source to a patient. The system further includes a compact, portable housing having a receptacle slot for removably receiving a segment of the disposable tubing. A fixed stroke pump is mounted in the case for engaging the segment of the disposable apparatus and pumping intravenous fluid therethrough. A motor is mounted in the housing and is connected for driving the pump upon energization thereof. A keyboard includes a rate key for selecting the infusion rate and a volume key for selecting the volume. The tubing is attached to the source of intravenous fluid, such as a bag. A display is mounted in the housing for visually displaying information in alphanumeric form. A microcontroller mounted in the housing receives the input signals and causes the display to provide a visual indication of the delivery rate parameters in alphanumeric form for selection and verification by the patient. The microcontroller energizes the motor so that the expansion chamber pump conveys the fluid through the disposable apparatus in accordance with the delivery rate parameters.
In the illustrated embodiment of our invention, the system includes a keypad mounted in the housing for enabling the user to send commands to the microcontroller. A detector mounted in the housing optically detects the presence of a bubble inside the segment of the disposable tubing and sends a bubble detect signal to the micro-controller.
The preferred embodiment of our programmable infusion system has the capability for detecting an interrupt condition, such as the failure to load a disposable apparatus therein, an occlusion in the disposable apparatus, a motor failure, a pump failure, or a bubble in the disposable apparatus. The microcontroller can then de-energize the motor in response to the detection of an interrupt condition, and cause the display means to display a warning of the interrupt condition in alphanumeric form. It can also cause an audible warning to be generated, such as a succession of beep tones, and a visible warning to be given in the form of an illuminated red LED.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects and advantages of the present invention will become apparent from the following description when read in conjunction with the accompanying drawings wherein:
FIG. 1 is a front elevation view of a preferred embodiment of the invention showing the main and reservoir housings;
FIG. 2 is a top view of the main housing detached;
FIG. 3 is a partial view like FIG. 1, with portions broken away to reveal details;
FIGS. 4-6 are like views in section taken on line 4--4 of FIG. 3 showing the pump in different stages of its stroke;
FIG. 7 is a block diagram of the control system of the embodiment of FIG. 1; and
FIG. 8 is a graph illustrating motor load under occluded and non-occluded conditions.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1 of the drawings, there is illustrated in an exploded view an exemplary preferred embodiment of the invention. The illustrated embodiment comprises a main or central housing, designated generally by the numeral 10, and a detachable reservoir housing, designated generally by the numeral 12. The main housing 10 houses the pump drive and actuating mechanism, as will be more fully described with respect to FIGS. 2 and 3-5, and the control means for the pump system. The control means comprises electronics for driving and controlling the drive of the pump unit for indicating various parameters and the like.
Referring to FIGS. 1 and 2, the main housing is of a generally box-like configuration formed of front and back half-shells 14 and 16. The face or face panel 16 is formed with an open slot 18 extending from the top to the bottom of the panel, and is open to the face thereof for receiving a disposable unit 20 comprising a portion of the pump unit. This slot communicates at the upper end, with the reservoir housing 12 to receive tubing extending therefrom. The slot is formed with smaller width portions at the upper inlet end and the lower outlet end for receiving conventional IV tubing. Enlarged sections 22 and 24 are designed to receive valve units 26 and 28 which are connected in fluid communication by an elastic tube member 30.
The disposable unit 20, as illustrated in FIG. 1, comprises said elastic tube member 30 of a selected length, diameter and bore size connected between said inlet valve 26 and said outlet valve 28, each of which are respectively connected to an IV supply line 32 and an IV delivery line 34. There is, therefore, a complete fluid path from supply line 32, through inlet valve 26, through elastic tube member 30, through outlet valve 28, and through IV delivery line 34. The elastic tube member 30 is preferably an elastomeric silicone, but may be any other suitable medical grade synthetic or natural rubber of between about fifty and seventy durometers on the Shore A scale. The member 30 must having sufficient elasticity to restore itself rapidly after being compressed sufficiently to provide the upper limits of volume to be pumped.
The member 30 for this configuration is selected to have a 0.100 inches ID and 0.160 inches OD, with an overall length of 1.5 inches and a length between the valves 26 and 28 of about 0.875. This gives a volume to assure self priming of the pump with the given check valves 26 and 28.
The check valves 26 and 28 comprise a substantially zero cracking pressure inlet check valve 26, which is preferably a duckbill type, which may have a cracking pressure of up to about 0.5 psi. The outlet valve 28 is preferably a 2 to 6 psi disc spring type.
The actuating mechanism of the pump unit, as best seen in FIGS. 3-6, comprises a ram or finger member comprising a foot member 36 mounted on the lower end of a reciprocating plunger unit 38, having a slot or yoke 40 therein in which an eccentric cam member 42 rotates. The eccentric cam unit 42 is mounted on the end of a motor driven shaft 44, which is driven by means of a DC electric motor 46 disposed within the housing. The motor 46 is preferably powered by either a lithium or alkaline 9 volt battery. The finger or slide member 38 is disposed between and guided by guide or wall members 48 and 50 within the housing.
The foot member 36 preferably has substantially the same length along the slot 18 as the member 30, so as to compress the member 30 to essentially zero internal volume. The member 30 is pressed between the foot member 36 and a stationary platen 52 on the opposite side of the slot 18.
The pump mechanism functions similar to any expansion chamber type pump, with the collapsing and expansion of the member 30 forming an expansion chamber pump. The unit becomes self-priming by virtue of the selection of parameters to provide for creation of sufficient pressure, with air therein to open the outlet check valve 28 and forces movement of the column of air therethrough. This follows the principal of Boyles Law wherein P'×V'=P"×V".
Referring back to FIG. 1, the unit in its preferred embodiment pumps fluid from a reservoir 54 contained within the reservoir housing 12. The reservoir 54 is preferably of a conventional construction of one-hundred milliliter volume bag made of PVC film and is disposable. The line 32 can be integrated with the original reservoir 54, or a connection luer lock can be used to connect the line 32 to a larger volume reservoir of infusion fluid. The reservoir housing 12 is of a box-like construction of opposed half-shells 58 and 60, shown in the illustrated embodiment as hinged together along a hinge connection 62, with the front panel 60 shown open. The reservoir housing 12 is constructed to detachably connect to the upper end of the main housing 10 by means of a bayonette type coupling. As illustrated, the upper end of the housing 10 is formed with central upwardly extending cylindrical pilot member 64, which extends into a cylindrical recess 66 in the bottom end of the reservoir housing 12. Radially extending tabs 63 on member 64 extend into annular slots 65 in the wall of recess 66. A pair of arcuate slots 68 and 70 formed in the upper end of the main housing 10 receive a pair of radially extending arcuate flanges 72 and 74 formed on the housing 12. Thus, to attach or detach the housing 12 from the upper end of the main housing 10, the reservoir housing 12 is axially aligned along the members 64 and 66, and rotated about the axis to alternately engage or disengage the flanges 72 and 74 with the arcuate slots 68 and 70. When the reservoir housing 12 is disengaged and detached from the main housing 10, it may be opened as illustrated, and the reservoir 54 either removed or replaced therein.
The control system for the present invention has some common features and components of co-pending application Ser. No. 07/518,987, filed May 4, 1990 now U.S. Pat. No. 5,078,683 dated Jan. 7, 1992, entitled "Programmable Infusion System", and assigned to the assignee herein, said application for which the issue fee was been paid on Oct. 17, 1991, is incorporated herein by reference as though fully set forth. The present invention, for example, incorporates an air in line (or bubble) detector, as disclosed in the aforementioned application. It may also include or incorporate an occlusion detector similar to that as set forth. However, an alternate detector system as will be sequentially explained is preferred.
Referring to FIG. 7, a block diagram of the control system is illustrated. The heart of the control system is a microcontroller 78, with user interface in the form of a keyboard on the face 16 of the unit, with motor control for controlling flow and various fault analysis. The system has the usual battery and power supply circuit 80 connected to power the overall system, with a keyboard interface 82 to enable an operator input to the microcontroller for control or selection of rate, volume, and to start and stop the unit. A LCD display 84 displays information to the user relative to operational parameters, including rate, volume, start and stop, and conditions of the unit. A number of monitoring and sensing functions, including external watchdog 86, signals the microcontroller, which in turn signals the user by audible means, such as a buzzer 88. Among the sensing functions are also a motor watchdog 90 monitoring the motor 46, which in turn is controlled by the microcontroller. Other sensors include a door open detection circuit 92 to detect the absence of tube 30 from slot 18, a battery condition detection circuit 94, air in line detection circuit 96 and an occlusion detection circuit 98. The control means includes means for detecting an interrupt condition from the group consisting of disposable means not loaded, occlusion in the disposable means, failure in the motor means, failure in the pump means, and bubble in the elastic segment of the disposable means, for de-energizing the motor means in response thereto and for causing the display means to display a warning of the interrupt condition in alphanumeric form.
The presence of an occlusion in the system, that is an obstruction that stops or substantially slows fluid flow, may be measured as a function of current used by the motor 46, a function of the speed of rotation of the motor 46, or a combined function of these two factors. The occlusion detection circuit 98 measures the current used by the motor 46 during the pumping stroke and also through the use of a hull effect shaft encoder 118, which senses mounting of a magnet 120 carried by the shaft 44 of the motor 46. An occlusion will cause either a variation in the current used by the motor 46 or a variation in the rotational speed of the shaft 44 or, in some cases, both variations will occur. The occlusion detection circuit 98 monitors these factors and presents data to the microcontroller 78 for decision making and generation of an error signal when the pressure of an occlusion is determined.
The microcontroller 78 is preferably a Motorola MC68HC711E9. The microcontroller 78 will be pre-programmed for all operational parameters, with the exception of specific volume and rate of delivery, which may be selected by the operator from the control panel. The operator controls infusion rates from the keyboard interface 82 with a rate control key 100, which may set the rate of delivery or infusion rate by pressing down the key until the rate desired is indicated by the LCD display. The infusion rates will be displayed at LCD 84 and consists of ten discrete steps between 25 and 250 millimeters/hr. in 25 millimeter/hr. increments. This key also allows the user to enable or disable the air in line detector circuit 96 and also to prime the unit before an infusion is started.
A volume key 104 is operational to set the infusion volume the same as above, with for example twelve infusion volumes chosen, arranging from fifty to three-thousand millimeters, with volumes for example fifty, one-hundred, two-hundred fifty, fifty, five-hundred, six-hundred, one-thousand, twelve-hundred, fifteen-hundred, eighteen hundred, two-thousand, twenty-four hundred and three-thousand. The volume is also indicated by LCD 84. A start and stop key 108 initiates the infusion and enables the user to stop the priming of the unit.
The LCD display 84 is divided into four quadrants, with the rate of infusion shown in the upper left, the volume selected in the upper right, and the volume actually infused at any time in the lower right. User messages will be displayed in the lower left which notify the user of the pump status, alarm conditions or pump errors. All of the alarm conditions previously mentioned will notify the user by message on the LCD display 84. In the preferred mode, alarm messages may be accompanied by an intermittent or constant audible tone, together with a red LED alarm. A fault LED alarm indicator may be provided at 114 in the form of a red LED. A run indicator 116 is provided in the form of a green LED.
In operation, an infusion unit is selected and loaded with the reservoir 54 of IV solution, with tubing 32 and 34 and disposable unit 20 attached thereto. The disposable IV reservoir 54 is mounted within the solution reservoir housing 12, and the housing 12 attached to the upper end of the housing 10, with the disposable tubing segment 30 placed in the receptacle slot 18 clipped or retained therein by any suitable means. Preferably, there is a snap fit between the check valves 26 and 28 and the enlarged sections 22 and 24 of the slot 18. The pump is primed and the delivery tube 34 is then connected to the patient infusion site in the normal manner, and the unit is activated to set the infusion rate and volume. Once the rate and volume has been set, the unit is then activated and allowed to run its normal rate to infuse the selected volume of IV solution. Once the volume has been reached, the machine will stop operation and may then be disconnected.
While we have illustrated and described our invention by means of a specific embodiment, it should be understood that numerous changes and modifications may be made therein without departing from the spirit and scope of the invention as defined in the appended claims. We further assert and sincerely believe that the above specification contains a written description of the invention and the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly concerned, to make and use the same, and further that it sets forth the best mode contemplated by us for carrying out the invention.
Therefore, the protection afforded our invention should only be limited in accordance with the scope of the following claims. | An infusion pump system, comprises disposable tubing having an elastic segment and one-way check valves at each end of the segment for conveying intravenous fluid from a source to a patient, a compact, portable housing having an open receptacle for removably receiving a segment of the disposable tubing, a reciprocating ram mounted in the housing for periodically engaging and compressing the segment of the disposable tubing for pumping fluid therethrough, a motor mounted in the housing for driving the ram upon energization thereof, a control system mounted in the housing for receiving input signals and energizing the motor so that the fluid is pumped through the disposable tubing in accordance with pre-selected delivery rate parameters. | 8 |
BACKGROUND OF THE INVENTION
[0001] The invention relates to a ventilation device for transmissions with a lubricant containing water, wherein the ventilation device is connected to the transmission housing via a line and has a pressure equalization opening leading to the environment.
[0002] In oil-lubricated transmissions there is a ventilation opening, which allows pressure equalization with the environment when the temperature in the transmission rises or falls due to operating conditions and which is usually equipped as a device with installations for retaining oil mist and for keeping away dirt from the environment.
[0003] WO 2007/098523 A1 discloses a lubricant containing water, which in addition to a high proportion of water contains an agent lowering the freezing point, such as glycol, and further additives and/or suspended matters. Further details as well as the advantages to be obtained with such a lubricant can be gathered from the above-mentioned publication.
[0004] DE 22 20 565 discloses a recirculating cooling system for oil-lubricated reduction transmissions. A fan recirculates air containing oil vapors from inside the transmission through a heat exchanger back into the transmission. The condensed oil is returned separately. There is no pressure equalization with the environment.
[0005] Water has a very low vapor pressure in comparison to lubricating oil, so that it evaporates easily. This leads to the fact that not only the amount of lubricant in the transmission becomes less and less, which soon results in the destruction of the transmission, but also the composition of the lubricant changes because the proportion of water becomes smaller and smaller.
[0006] Thus it is the object underlying the invention to remedy this disadvantage and to counteract the loss of water to the environment.
SUMMARY OF THE INVENTION
[0007] According to the invention, this is achieved by the fact that the ventilation device comprises at least one container formed as a condenser to which evaporated water passes through the line, said container being provided for this purpose with means for dissipating heat, wherein the condensate passes from said container back to the transmission.
[0008] When the transmission is heated up due to operating conditions, the air which is present in the lubricant-free space expands and there is increased evaporation, so that a mixture of air and water vapor flows through the line into the evaporating device. In the evaporating device the water vapor is condensed and the air is allowed to escape into the environment. Thus a separation of air and water vapor and a condensation of the water vapor occur simultaneously with the pressure equalization.
[0009] Heat dissipation is required for the condensation, which heat dissipation is achieved in various ways. Either by a group of pipes mounted inside the at least one container and flown through by a suitable cooling agent or by cooling ribs arranged at the outside of the container, or a combination of both. If the transmission is part of a motor vehicle, the cooling ribs should be exposed to the air stream, if possible. This is easily possible due to the fact that the device does not need to be mounted at the transmission itself, but is connected thereto by a line. If the line continuously rises and its cross section is sufficiently dimensioned, it can at the same time serve as a return line for condensed water. In this way, only a single tube is required between the transmission and the device.
[0010] However, the device can also be arranged at the same height as or lower than the transmission. In these cases the line, at least in the container, leads downwards and ends below the level of the condensate. In this way, the condensate can be drawn back in the case of a pressure drop in the transmission.
[0011] In an advantageous further development of the invention, the device consists of two containers arranged essentially at the same geodetic height and containing a liquid, wherein the deepest points of the two containers communicate with one another via a U-shaped duct and wherein the line opens into one of the containers and the other container has the pressure equalizer opening at its top. The two containers are interconnected in the manner of a siphon. When the pressure changes in the transmission, the liquid is displaced in the siphon, wherein the levels of liquid in the two containers move apart from one another. Water vapor condenses in the liquid, wherein a part thereof flows back into the transmission when the level of liquid has increased sufficiently or the pressure in the transmission has dropped.
[0012] Previously to the initial operation, the siphon and the two containers are filled with such a large amount of liquid that their levels in this initial state reaches up to the orifice of the line. Due to this fact returning the condensate into the transmission becomes more even.
[0013] The liquid in the siphon and in the two containers can be water, an agent lowering the freezing point, for example, glycol or a mixture of both. Depending on the conditions and requirements, the one or the other is to be preferred. If no temperatures below the freezing point are to be expected, water is preferable because in this way the composition of the lubricating liquid in the transmission remains unchanged. Otherwise the agent lowering the freezing point is more advantageous.
[0014] In a further development of the invention, the space filled with liquid contains a porous material of high thermal conductivity. This improves heat transfer and condensation and prevents fluctuating of the levels of liquid in the two containers. As the porous material, in particular stainless steel wool has proved its worthiness.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 : schematic representation of the device according to the invention in a first embodiment;
[0016] FIG. 2 : schematic representation of the device according to the invention in a second embodiment, in its initial position;
[0017] FIG. 3 like FIG. 2 , when the transmission is heated up;
[0018] FIG. 4 like FIG. 2 , when the transmission is cooled down;
[0019] FIG. 5 schematic representation of the device according to the invention in a third embodiment.
DETAILED DESCRIPTION
[0020] In FIG. 1 , a transmission is designated summarily with reference numeral 1 and a ventilation device according to the invention with reference numeral 11 . As a simplifying example, the transmission 1 herein contains a driving shaft 6 having a gear 5 and a driven shaft 8 having a gear V. Details which are common for transmissions, such as bearing and housing partition, are not elaborated on. In practice, it can be any transmission, such as the shift gearbox or the rear-axle transmission with differential of a motor vehicle.
[0021] The lower part of the transmission contains a lubricating liquid 2 having a level 4 . The gear 7 immerges into the lubricating liquid 2 . The upper region of the transmission 1 has an opening 9 . Otherwise the transmission 1 is closed and thus has no flow connection with the environment. The lubricating liquid contains a considerable amount of water and is described in more detail in WO 2007/098523 A1. A line 10 leads steadily upwards from the opening 9 up to the ventilation device 11 according to the invention. In this case, the ventilation device 11 comprises a container 17 , inside of which there is a cooling pipe coil 15 . It is flown through by a preferably liquid cooling agent. Alternatively or additionally the container 17 can be provided with cooling ribs 16 . The container 17 has an opening 13 at its highest point, which, as a conventional ventilation opening, protects against the intrusion of dirt with a cap 14 .
[0022] By way of this simplest embodiment of FIG. 1 , the basis of the function can be recognized. The water evaporating due to friction and heating in the transmission 1 (and, if applicable, further liquids present in the lubricant) rises via the line 10 into the ventilation device 11 . There it condenses due to cooling, and the condensate flows back again into the transmission 1 . Since the ventilation device 11 is a separate unit, it can also be arranged at some distance from the transmission, such as at a place where it is exposed to the air stream. In this case the cooling ribs are useful; otherwise dissipation of the condensation heat is primarily effected by the cooling pipe coil 15 . Due to the opening 13 there is no change in pressure in the transmission or in the container 17 .
[0023] In the embodiment of FIG. 2 the ventilation device is formed by two containers, a first container 21 and a second container 22 , both essentially at the same geodetic height, thus side by side. The line 10 rising from the transmission opens into the first container 21 at a certain height (orifice 23 ). At its highest point the second container 22 has a conventional ventilation opening making the connection with the environment. The lowermost points 25 , 26 of the two containers 21 , 22 are interconnected via a U-shaped pipe 27 , so that they form vessels communicating for a liquid.
[0024] The U-shaped pipe 27 and the lowermost regions of the two containers 21 , 22 are filled with a liquid corresponding to the levels of liquid 30 , 31 . The spaces 28 and 29 , respectively, on top of it contain air and water vapor. In the initial position shown in FIG. 2 (previously to the first operation of the transmission), both levels 30 , 31 are equally high. Herein the level 30 is somewhat below the orifice 23 of the line 10 . The liquid is one of the components of the lubricating liquid or the lubricant itself or a mixture of their components.
[0025] In addition to the filling of liquid, the U-shaped pipe 27 and the lower regions of the two containers 21 , 22 still contain another filling 32 made of a porous material, which takes up and conducts heat well. Though this filling 32 is to allow the flow of the liquid between the two containers 21 , 22 , it dampens it. The main function of the filling 32 is to take up and dissipate heat, see further description of function hereinafter. Stainless steel wool has proven to be especially efficient for this purpose, not least due to its good thermal conductivity. The U-shaped pipe 27 can be additionally provided with cooling ribs 33 .
[0026] In order to explain the function, at first the transition from the initial state of FIG. 2 to the state of FIG. 3 will be described: During operation the transmission heats up and with it the lubricant, wherein the water contained therein begins to evaporate and the air/vapor mixture expands in the space above the lubricant. This causes the mixture to rise through the duct 10 into the space 28 , in which the mixture at first displaces the liquid present there—causing the level 30 to decrease to 30 ′—and subsequently bubbles through the liquid in the U-shaped pipe 27 . Herein the water vapor condenses—especially fast due to the fact that it touches the filling 32 —, and the air reaches the second container 22 . The air rises therein and exits—just as the air displaced by the risen level 31 ′—through the ventilation opening 34 into the environment. If the liquid in the U-shaped pipe 27 and in the lower regions of the two containers 21 , 22 contains a substance lowering the freezing point (glycol or another superior-grade alcohol), this substance absorbs the water vapor, wherein its volume is increased, and mixes with the condensate. Thus the condensing effect of this arrangement is a multiple one.
[0027] In order to explain the function, furthermore the transition from the state of FIG. 3 to the state of FIG. 4 will be described: when the transmission is stopped, it cools down relatively quickly, and with it the air/vapor mixture present in the space 28 of the first container 21 . Due to this fact a vacuum develops in the space 28 , causing the level 30 ′ in the first container 21 to rise to the level 30 ″ and correspondingly the level 31 ′ to decrease to the level 31 ″. This is not impeded since air is able to flow in through the ventilation opening. However, the flow in the duct 27 is retarded by its filling 32 of steel wool. The rising level 30 ″ in the first container 21 finally reaches the opening 23 , in which the downwards leading line 10 opens into the container 21 . Due to the fact that the volume of the filling of liquid has increased by absorbing water and mixing with water, the additional amount flows back into the transmission 1 through the line 10 . This ensures that amount and mixing ratio of the total amount of liquid do not change.
[0028] The embodiment of FIG. 5 differs from the one of FIG. 1 in that the line 110 in the container 117 is led downwards far enough for its open end 123 to immerge into the condensed water 132 . The end 123 lies below the level of liquid 130 , so that, when the transmission is cooled down, condensate is drawn back into the transmission. Due to this fact there is great freedom in arranging the container 117 . It can be placed in the vehicle such that it is exposed to the air stream, even near the ground.
[0029] Within the framework of the invention, the described embodiments can be modified in various ways; in particular, individual features thereof can be combined with one another. | A ventilation device for transmissions with lubricant comprising water, the device being disposed above the transmission ( 1 ) and being connected thereto by way of a line ( 10 ) and comprising a pressure equalization opening ( 13 ) that leads to the surrounding environment, is to operate without loss of evaporating water to the environment. To this end, the device comprises at least one container ( 17 ) designed as a condenser for evaporated water rising through the line ( 10 ), the container being provided with a cooling element for dissipating heat ( 15 ), the condensate passing from said container ( 17 ) back to the transmission ( 1 ). In one variant, two containers containing a fluid are described which communicate with one another by way of a U-shaped channel. | 5 |
[0001] The invention relates to a chisel bit arrangement for fastening to a plough-body element of a mining plough for underground mining, particularly of a coal plough for the excavation of steeply disposed coal seams, having a plurality of bit pockets for accommodating, preferably demountably, respectively one bit per bit pocket. The invention relates further to a mining plough for plough appliances for the exploitation of minerals in an inclined formation, particularly a coal plough for the excavation of steeply inclined coal seams, with a plough body, with guide means for guiding the mining plough on a guide device of the plough appliance and having bit arrangements having a plurality of bit pockets for accommodating, preferably demountably, respectively one bit per bit pocket.
BACKGROUND OF THE INVENTION
[0002] In the last two decades, the automatic mechanisation of the extraction of flatly disposed coal seams, of 0 to 20 gon (0 to 18 degrees), and of slightly inclined deposits, of gradients of 20 to 40 gon (18 to 36 degrees), has resulted in output rates of up to 1,500 t/h with the use of mining ploughs in plough appliances, and over 2,600 t/h with the use of shearer loaders. Meanwhile, more than 90% of the quantity of coal excavated underground originates from flat or slightly inclined deposits, since the latter can be excavated substantially more economically by means of the existing mining technology than can coal seams or other mineral deposits in a greatly inclined disposition, of a gradient of more than 40 gon (36 degrees), or in a steep disposition, of 60 to 100 gon (54 to 90 degrees).
[0003] A coal plough, which is provided with a bit carrier that is pivotable according to the direction of travel, and which is moved back and forth reversingly in the underground face, parallelwise in relation to the excavation front, by means of a continuous plough chain, has proved successful for the excavation of flatly disposed coal seams. Each bit carrier is provided with a multiplicity of bit pockets, in which, in turn, plough bits can be accommodated in a demountable manner. In order to achieve a different excavation height by means of the same coal plough, there is additionally provided a roof bit carrier, which is arranged centrally between the two pivotable bit carriers and which can be extended or retracted in an appropriate manner, for example by means of a worm gearing. Insofar as possible, the same bit pocket is fixed both on the pivotable bit carriers and on the roof bit carrier, in order to minimize the production costs. DE 39 23 969 C2 describes, by way of example, such a coal plough having pivotable bit carriers and roof bit carriers.
[0004] There are multiple differing possibilities for anchoring a plough bit in a bit pocket in such a way that the necessary mining work, in particular the excavation of coal or other minerals at the excavation front, can be performed reliably and with an adequate tool life by means of the plough bits. DE 101 61 015 A1 describes, merely by way of example, a bit arrangement having bit pockets and a plough bit that can be fastened in the bit pocket.
SUMMARY OF THE INVENTION
[0005] An object of the invention is hereby to create a bit arrangement and a mining plough that can be used advantageously in the case of mining ploughs, or plough appliances, particularly for the excavation of steeply disposed mineral deposits, and that render possible economic excavation of such mineral deposits, particularly coal seams.
[0006] These and further objects are achieved, in respect of the bit arrangement, in that at least two bit pockets are fixed in recesses on a front side of a bit strip, this bit strip being provided, on a back side, with at least one groove indentation for the positive engagement of a locking projection on the plough-body element and being detachably fastened to the plough-body element by means of detachable fastening means. In the case of the bit arrangement according to the invention, a plurality of bit pockets are therefore fixed on a bit strip, which constitutes an exchangeable part that, in an appropriate manner, can relatively easily be fastened to the plough-body element or detached from the latter. The groove indentation, on the back side of the bit strip, and a locking projection, on the plough-body element, that engages positively in the groove indentation ensure, together with the fastening means, that the bit strip does not get lost during the mining work and that all forces transferred into the bit pockets via the plough bits can be transferred reliably into the associated plough-body element of the mining plough.
[0007] In the case of a particularly preferred design, the bit strip has, on the back of the front side, a longer top limb and a shorter locking limb, which are offset in relation to one another in respect of height and between which the groove indentation is realized. Such a design of the bit strip enables it to be pushed onto the plough-body element with, at the same time, large-area contact between the bit strip on the one hand and the plough-body element on the other hand, whereby not only is a better supporting of the bit strip ensured, but the mounting, or demounting, until the engagement of the groove indentation and locking projection is ensured, is assisted, in that the surfaces bearing on one another constitute guide surfaces. It is particularly advantageous if the back edge of the top limb constitutes a locking projection for the purpose of positive setting into a locking indentation on the plough-body element, in order that the bit strip is positively locked on the plough-body element at two regions that are spaced apart from one another, and in order that the detachable fastening devices are not subjected to load by the large forces occurring during operational use.
[0008] The top limb can be provided, in particular, with two round feedthroughs for, respectively, one fastening means per feedthrough. Further, preferably, the front side of the bit strip can graduate, via a sloping surface, into the short limb, in order to achieve, with the sloping surface, a favorable removal of the mined-in material into a discharge channel, in particular a chute channel of the plough appliance, which sloping surface, particularly advantageously, when in the mounted state, lies flush relative to a slope or sloping surface on the front side of the plough-body element.
[0009] In the case of all designs, it is advantageous if the bit pockets are anchored in, in particular welded into, recesses that are open towards the top side of the top limb of the bit strip. The back side of the recesses can then constitute a stop, via which the forces introduced into the bit pockets are deflected first into the bit strip and then, in particular via the surrounding walls of the groove indentation, into the plough-body element. The invention offers particular advantages if the bit strips can be used multiply, in the manner of a modular principle, on a plough-body element or on differing plough-body elements. At the same time, it is advantageous if it is ensured, by means of the bit strips, that adjacently located plough bits are disposed such that their bit tips are offset relative to the direction of travel of the mining plough, in order to improve the breaking-out of the minerals and the removal of the mined-in material. Depending on the width and design of the plough-body element, at least the top limb of the bit strip can be realized in the form of a parallelogram, in order that this offset engagement of the bit tips of the individual plough bits is already achieved through the basic shape of the top limb. In order to achieve at the same time a symmetrical distribution of the individual bits over the width of the mining plough, however, the front side, in the case of an alternative, second embodiment of a bit strip, can extend in the form of a wedge or curve, and the top limb of this bit strip has the greatest depth in the center. The bit pockets can then be arranged on the front side in such a way that one bit pocket is located in the center, and the plough bit fastened in this central bit pocket is located with a forward offset in the direction of excavation relative to all other plough bits. A wedge-shaped or curved bit strip is suitable, in particular, for use in the case of use of plough-body elements of small width and/or in the center of a wide plough-body element fitted with a plurality of bit strips. In the case of all designs, it is particularly advantageous if approximately 4 to 8, in particular 4 to 6, bit pockets are arranged per bit strip.
[0010] The above objects and others can be achieved in the case of a mining plough having a divisible plough body having two plough-body basic elements, which comprise the guide means, and having at least one plough-body intermediate element that is insertable between the plough-body basic elements for the purpose of increasing the width of the plough body, or the extraction height of the mining plough, at least one bit strip being fastened or fastenable to the plough-body intermediate element by means of detachable fastening means, which bit strip has at least two recesses for the purpose of fixing at least two bit pockets on a front side of the bit strip and which, on the back side, is provided with at least one groove indentation for the positive engagement of a locking projection realized on the plough-body intermediate element.
[0011] According to an advantageous design, the plough-body intermediate element can be provided, on a front side facing in the direction of excavation, with a forwardly projecting locking strip, as a locking projection, the top surface of which extends as far as into a locking indentation realized so as to be backwardly and upwardly offset relative to the locking projection, such that the bit strip is positively anchored on the plough-body intermediate element at two regions that are spaced apart from one another. A top surface of the plough-body intermediate element can be provided with two blind cutouts, at the base of which or close to the base of which fastening screws of the fastening means can be anchored. For this purpose, each blind cutout can be provided with a threaded bore at its base, or it is preferably provided with countersinkings for the purpose of accommodating screw heads of the fastening screws. Expediently, each plough-body intermediate element also has, at a transition of its front side to the underside, a slope that acts particularly advantageously in combination with the sloping surface on the bit strip, in order to improve the removal of mined-in materials into a discharge channel in the case of the excavation of steeply disposed deposits.
[0012] The fastening means for detachably fastening the bit strip to the mining plough can have, in particular, fastening bushes, which can be formed by a cylinder without, or preferably with, an annular collar. In the case of a possible design, the annular collar, when in the mounted state, can bear on the top limb of the bit strip and be clamped against the top limb of the bit strip by means of the fastening screw, which, by means of its screw head, is anchored on the plough-body intermediate element, in particular in the blind cutout on the plough-body intermediate element. Alternatively, the annular collar, when in the mounted state, can also be spaced apart from the top limb and, for example, only accommodate in a countersunk manner the nut for tightening the fastening screw. The fastening screw then exclusively secures the fastening bush against loosening, e.g. as a result of vibrations during operational use, without the bit strip being clamped against the plough-body intermediate element by means of the fastening bush.
[0013] Further advantages and developments of the invention are given by the following description of exemplary embodiments, shown schematically in the drawings.
[0014] Further, these and other objects, aspects, features, developments and advantages of the invention of this application will become apparent to those skilled in the art upon a reading of the Detailed Description of Embodiments set forth below taken together with the drawings which will be described in the next section.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The invention may take physical form in certain parts and arrangement of parts, a preferred embodiment of which will be described in detail and illustrated in the accompanying drawings which form a part hereof and wherein:
[0016] FIG. 1 shows a portion of a plough appliance for excavating steeply disposed coal seams by means of a mining plough according to the invention, including a bit arrangement, according to the invention, according to a first exemplary embodiment;
[0017] FIG. 2 shows a second exemplary embodiment of a mining plough having a bit arrangement according to the invention;
[0018] FIG. 3 shows the mining plough from FIG. 2 as viewed from the front;
[0019] FIG. 4 shows a partially opened-up sectional view through a fastening means for fastening a bit strip to a plough-body element;
[0020] FIG. 5 shows a sectional view along V-V in FIG. 4 ;
[0021] FIG. 6 shows a partially opened-up side view of a bit strip according to the invention;
[0022] FIG. 7 shows a side view of the bit strip from FIG. 6 ;
[0023] FIG. 8 shows the bit strip from FIG. 7 , as viewed from the left; and
[0024] FIG. 9 shows a perspective view of the bit strip from FIGS. 6 to 8 , with the fastening means shown in an exploded representation.
DETAILED DESCRIPTION OF EMBODIMENTS
[0025] Referring now to the drawings wherein the showings are for the purpose of illustrating preferred and alternative embodiments of the invention only and not for the purpose of limiting same, in FIG. 1 , reference 1 denotes in general a plough appliance for mining coal in an underground, steeply disposed coal seam of a gradient of, for example, more than 45 gon (40.5 degrees). The plough appliance 1 can be moved parallelwise in relation to the excavation front in the steeply disposed deposit, and FIG. 1 shows a top view of the plough appliance 1 from the excavation front, the tilt of the plough appliance not being represented, however, for reasons of clarity. The plough appliance 1 is composed, in known manner, of a multiplicity of trough pans 2 of mutually identical construction, which, here, are realized as preferably angular trays and which, by means of a lower limb 3 , bear on the so-termed footwall that is inclined, relative to the horizontal, at an angle corresponding to the gradient, while the limb 4 aligned approximately perpendicularly thereto extends, when in operational use, parallelwise in relation to the excavation face, or excavation front. Screwed on to the limb 4 of the trough pans 2 , close to its upper end, are supporting arms 5 , by means of which an upper guide bar element 6 A is supported, at a sufficient distance, per trough element 2 , such that the upper guide bar elements 6 A, arranged in alignment in relation to one another, can constitute an upper guide device for the mining plough denoted in general in FIG. 1 by the reference 50 . Attached to the lower limb 3 of the trough pans 2 , and opposite and parallel to the upper guide bars 6 A, are lower guide bar elements 6 B, as lower guide devices of the plough appliance 1 , and the mining plough 50 is guided by means of a total of four pivotable slide shoes 7 , of which only the rear slide shoes can be seen in FIG. 1 , on the upper guide bar elements 6 A, on the one hand, and on the lower guide bar elements 6 B, on the other hand. The guide bar elements 6 A, 6 B and the mining plough 50 , when in the assembled state, are at a relatively large distance from the limb 4 of the trough pans 2 .
[0026] In the case of a steeply disposed coal seam, mining work is performed by means of the mining plough 50 only in the arrow direction A, for which purpose the mining plough 50 is either moved upwards, in the arrow direction A, by means of two continuous plough chains 8 A, 8 B attached to the mining plough 50 , on to a so-termed head gate for the purpose of performing mining work, or it is moved back downwards, contrary to the arrow direction A, to a removal gate, without performing mining work during this back movement. The material mined-in during a movement of the mining plough 50 in the direction of excavation A is dropped into the tray-shaped trough. The mined-in material is caused to slide off towards the removal gate by the actually oblique position of the trough pans 2 , or of the plough appliance 1 . For a more detailed description of the structure of the plough appliance 1 , reference is made to a protective-right application of the applicant, filed on the same date for the plough appliance and the mining plough, and the disclosure content of which is included here by mention.
[0027] Shown in the exemplary embodiment according to FIG. 1 is a mining plough 50 composed of a total of four plough-body elements, namely, two outer plough-body basic elements 51 , to which the guide shoes 7 and the plough chains 8 A, 8 B are attached, or are fastened in a pivotally movable manner, and two plough-body intermediate elements 55 , which are demountable from one another and which are each fastened to one of the plough-body basic elements 51 . Each plough-body basic element is further provided, respectively, with a pivotable bit carrier 52 , which, respectively, is pivotable about a pivot pin supported on the plough-body basic element 51 . Each bit carrier 52 is equipped with, in this case, seven plough bits 54 , and the pivoting capability of the bit carriers 52 ensures that the plough bits 54 are in active engagement with the excavation front only when the mining plough 50 is pulled in the direction of excavation A. The two plough-body intermediate elements 55 are identical to one another in their structure, and serve to increase the width, or excavation height, of the mining plough 50 in comparison with a coal plough consisting only of the two plough-body basic elements 51 .
[0028] The protective-right application of the applicant submitted on the same date as the present application, and to which reference has already been made above, also relates, in particular, to the structure and the nature of the connection of the plough-body basic elements 51 to one or more plough-body intermediate elements 55 , and reference is made to this protective-right application for the purpose of complementing the disclosure. The invention relates, in particular, to the design and the structure of bit arrangements 10 , with which the plough-body intermediate elements 55 are provided. In FIG. 1 , each plough-body intermediate element is equipped with a single bit strip 11 , according to a first embodiment. Before the structure of this bit strip 11 is described, however, reference is first made to FIGS. 2 and 3 , which show an alternative, second exemplary embodiment of a mining plough 150 having a plurality of bit arrangements, or bit strips, on the plough-body intermediate element 155 .
[0029] As clearly evident from a comparison with FIG. 1 , the mining plough 150 shown in FIGS. 2 and 3 has a significantly greater width than the mining plough of FIG. 1 , although only a single plough-body intermediate element 155 is inserted between the two plough-body basic elements 151 . In the case of the mining plough 150 , however, the plough-body intermediate element 155 consists of a wide, single-piece body, on which three differing designs of bit arrangement 110 , 110 ′ and 10 are arranged. The plough-body intermediate element 155 is detachably connected, respectively, to an outer plough-body basic element 151 , fastened to which, respectively, so as to be pivotally movable, are two slide shoes 107 for the purpose of guiding the mining plough on the coal plough appliance. An aspect according to the invention consists in the bit arrangements 10 , 110 and 110 ′ being realized as detachable wearing parts that allow both rapid exchange and multiple use. For this purpose, each bit arrangement 10 , 110 and 110 ′ according to the invention has a bit strip 11 , 111 and 111 ′, respectively, and five bit pockets 130 are anchored, respectively, on each bit strip 11 , 111 and 111 ′. In turn, a plough bit 131 is inserted in each bit pocket 130 .
[0030] Reference is now made to FIGS. 4 to 9 , in which the bit arrangement 110 , having a bit strip 111 that in this case is realized with a base area approximately in the form of a parallelogram, is shown exemplarily in detail. In particular, FIGS. 5 to 7 and FIG. 9 make clear that each bit strip 111 has a cross-section that is substantially constant over the width, and comprises a longer, thicker top limb 112 , as well as a shorter locking limb 113 beneath the top limb 112 . A backwardly open groove indentation 114 , in which there engages positively the locking projection 156 , shown in FIG. 5 , on the front side 157 of the plough-body intermediate element 155 , is realized between the top limb 112 and the locking limb 113 , which are connected via a thick base that constitutes the front side 115 . The front side 115 of the bit strip 111 graduates into the shorter locking limb 113 via a sloping surface 116 . The top limb 112 is provided, at the back edge 117 , with an offset, enabling the top limb 112 , via its back edge 117 , to constitute a locking projection, which, again shown by FIG. 5 , in the mounted position is set positively into a locking indentation 158 in the plough-body intermediate element 155 . In the mounted position, therefore, each bit strip 111 is positively connected to the plough-body intermediate element 155 via two tongue-and-groove connections extending substantially parallelwise in relation to the front side 115 .
[0031] Each bit strip 111 is provided with, in this case, respectively five recesses 160 that are open forwardly, towards the front side 115 , and upwardly, towards the top surface 112 ′ of the top limb 112 . In all exemplary embodiments, each bit strip 112 has respectively five recesses 160 realized so as to be identical to one another, and a bit pocket 130 , in which a plough bit 131 is demountably inserted in a manner known per se, is fixed, in particular welded into, each recess 160 . In a preferred design, in this case the same bit pockets 130 and preferably the same plough bits 131 are used both on the bit strips 11 ( FIGS. 1 to 3 ) of the bit arrangements 10 and on the bit strips 111 of the bit arrangements 110 , 110 ′.
[0032] Reference is now made again to FIGS. 1 to 3 . Bit arrangements 10 , each consisting of a single bit strip 11 , are fastened to the plough-body intermediate elements 55 of the mining plough in FIG. 1 . A bit arrangement 10 of like structure, comprising a bit strip 11 , is also mounted centrally on the plough-body intermediate element 155 , between the bit strips 111 , in the form of a parallelogram, attached on the left of this bit strip 11 , and the bit strips 111 ′ attached on the right. The bit arrangements 110 and 110 ′ differ, basically, only in the angular position of the parallelogram and in the possibility of application, to that extent defined, on the left or right, respectively, on the plough-body intermediate element 155 , all bit strips 11 , 111 , 111 ′ being in each case fastened positively to the plough-body intermediate elements 55 or 155 in an identical manner and by means of the same fastening means 70 . The structure and fastening of the bit strips by means of the fastening means 70 is now to be explained.
[0033] Each top limb 112 of the bit strips 111 has two circular feedthroughs 122 , into which fastening bushes 72 , here provided with an annular collar 71 , can be inserted from above. Each fastening bush 72 has a central, stepped through-bore 73 for the feeding-through of a fastening screw 74 and for the countersunk receiving of a fastening nut 77 . Each fastening screw 74 , in turn, has a screw head 75 , and has a threaded portion 76 , on to which the fastening nut 77 can be screwed from above when the bit strip 111 is in the mounted position on the plough-body intermediate element 155 and, accordingly, the groove indentation 114 and the locking projection 156 , or the locking indentation 158 and the back edge 117 of the top limb 112 , engage positively in one another. This positive mutual engagement in two regions, over relatively long surfaces in each case, can be sufficient to divert into the body of the plough-body intermediate elements all forces exerted upon the plough bits when in operational use, and it remains only for the fastening bushes to secure this position if necessary. Then, when fastening bush 72 is clamped against the body of the plough-body intermediate element by means of the fastening screw 74 , the annular collar could have a small air gap in relation to the top limb. Alternatively, the annular collar 71 could press, by means of its lower annular flange, against the top surface 112 and, through tightening of the fastening nut 77 , this mounting position can be additionally secured against loosening. In order to anchor the screw head 75 of the fastening screws 74 on the plough-body intermediate element 155 , a top surface 162 is provided, extending above the locking projection 156 and having respectively one blind hole 163 per fastening device 70 , and a milled-out groove 164 , into which the screw head 75 can be inserted, preferably so as to be secure against rotation, as shown, in particular, by FIGS. 4 and 5 , is provided close to the base of the blind hole 163 . In order to demount the bit strips 111 , it is necessary either first to remove the fastening bushes 72 , or the entire bit strip 111 is moved transversely relative to the direction of movement, or direction of excavation, of the mining plough, with the nuts 77 having been loosened but with the fastening bushes 72 still mounted, until the screw heads 75 are released from the milled-out grooves, in order then, after removal of the fastening bushes 72 and the fastening screws 74 , for the bit strips to be drawn out forwards, as a result of which the positive engagement of the groove indentation 114 and the locking projection 156 , or of the back edge 117 and the locking indentation 158 , is only then released. In the mounted state, the slope 116 on the front side 115 of the bit strip 11 lies in approximately flush alignment relative to a sloping surface 161 via which the front side 157 of the plough-body intermediate element 155 graduates into an underside.
[0034] Whereas the bit strips 111 and 111 ′ can be multiply attached to the same plough-body intermediate element 155 , the bit strip 11 is suitable for attachment both to the plough-body intermediate elements 55 and to the plough-body intermediate element 155 . The bit strip 11 is not realized in the form of a parallelogram, but has a front side 15 extending in the form of a curved arc, as shown particularly clearly by FIG. 2 , for which reason the middle plough bit of the five plough bits 131 fastened to the bit strip 11 projects further forwards in the direction of excavation than the plough bits 131 , fastened adjacently to this middle plough bit, on the same bit strip 11 . Consequently, in the case of the mining plough 50 , an approximately W-shaped profile of the bit tips of all plough bits 131 and 54 can be achieved.
[0035] For the specialist, the preceding description gives rise to numerous modifications, which are intended to come within the protective scope of the appended claims. The figures show only two exemplary embodiments of a mining plough. It is understood that the intermediate body shown in FIG. 1 could be applied as only one intermediate body or, also, as more than two intermediate bodies, between the plough-body basic elements. It would also be possible to use other, differently designed plough-body intermediate elements, to which more or fewer bit strips are attached. The number of bit pockets and plough bits per bit strip can vary between three and eight, in particular between four and six. The plough bits are preferably detachably fastened in the associated bit pockets. Since the bit strips can be demounted from the plough body, however, fixed anchoring of the plough bits in the bit pockets would also be possible.
[0036] Further, while considerable emphasis has been placed on the preferred embodiments of the invention illustrated and described herein, it will be appreciated that other embodiments, and equivalences thereof, can be made and that many changes can be made in the preferred embodiments without departing from the principles of the invention. Furthermore, the embodiments described above can be combined to form yet other embodiments of the invention of this application. Accordingly, it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the invention and not as a limitation. | A bit arrangement for fastening to a plough-body element of a mining plough for underground mining, particularly of a coal plough for the excavation of steeply disposed coal seams, having a plurality of bit pockets for accommodating, preferably demountably, respectively one bit per bit pocket. In order thereby to create a bit arrangement and a mining plough that can be used advantageously for the excavation of steeply disposed mineral deposits and that render possible economic excavation of such mineral deposits, at least two bit pockets are locked in recesses on a front side of a bit strip, which is provided, on a back side, with at least one groove indentation for the positive engagement of a locking projection on the plough-body element and is detachably fastenable to the plough-body element by means of detachable fastening means. | 4 |
BACKGROUND OF THE INVENTION
This invention is directed to an improved stretch-wrap film dispenser wherein the dispenser can be manually carried around an article to wrap the article with the tension of the stretch-wrap film being manually controlled by control of the brake.
When a plurality of packages are grouped together, it is desirable to combine them into a load, often of the size of a pallet so that the merchandise can be transported and stored in pallet-size units. The stretch-wrap film can be wrapped around such a group to unitize the packages. The stretch-wrap film is a polymer sheet film of resilient nature. The stretch-wrap film must be applied in the tensioned, stretched form in order to securely wrap the plurality of packages into a unit.
Various types of machinery are available to move a roll of stretch-wrap film around articles to be wrapped, and similar apparatus is available where articles to be wrapped are rotated adjacent a fixed roll of stretch-wrap film. For the most part, these devices are fairly completely mechanized and powered. As a result of this, the equipment becomes complex and expensive.
Such mechanical strutures have tension control means thereon so that a constant tension is applied during the entire wrapping process. When fully mechanized, such constant tension is a desirable goal. However, when the roll is manually moved arond the load being stretch-wrapped, variations in tension from one wrapping turn to the next may be easily adjusted by the worker as he wraps the packages. Thus, there is need for a stretch-wrap film dispenser where the worker can quickly, conveniently and accurately adjust the tension of the stretch-wrap film.
SUMMARY OF THE INVENTION
In order to aid in the understanding of this invention, it can be stated in essentially summary form that it is directed to an improved stretch-wrap film dispenser for use with stretch-wrap film wound upon an elongated core or hollow mandrel which extends past the film on both ends. The dispenser includes handles rotatably mountable on the mandrel at each end thereof and inter-engaging brake means between the handle and the core so that adjustment of the brake controls unwinding tension of the stretch-wrap film as the worker carries it around the packages to be wrapped into a unit. Control of the brake is by rotation of a nut on a threaded shaft so that once made, the tension stays relatively constant until nut rotation is manually accomplished. When the film is on a large core, a plug may be employed for carrying an extended, axial tube. Instead of a spiral surface as on a nut and stud, a spring may be used to control the brake tension.
It is an object of this invention to provide an improved stretch-wrap film dispenser which is economic of construction, easy to use and which accurately controls the tension and positioning of stretch-wrap film as it is wrapped around a plurality of packages to join them into a unit.
It is a further object of this invention to provide an improved stretch-wrap film dispenser which acts with an extended core having stretch-wrap film thereon, or with an extension to the core where the core is of large diameter so that an axial bearing surface is provided on which a handle sleeve can be positioned. The handle sleeve has a spiral surface acting with an internal tension member or acts with a spring to control the pressure on friction surfaces between the handle sleeve and the roll of stretch-wrap film.
It is another object of this invention to provide an improved stretch-wrap film dispenser which is sufficiently economic of construction to be employed as a throwaway device and is sufficiently precise to permit the operator to wrap packages into a unit with properly controlled tension.
The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. The present invention, both as to its organization and manner of operation, together with further objects and advantages thereof, may be best understood by reference to the following description, taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side-elevational view of the first preferred embodiment of the improved stretch-wrap film dispenser of this invention, with parts broken away and parts taken in section.
FIG. 2 is an exploded isometric view thereof without the stretch-wrap film and its extended core.
FIG. 3 is an enlarged longitudinal axial sectional view of one end of the strcture of FIG. 1.
FIG. 4 is a view similar to FIG. 3, with some parts taken in axial section and with the extended central core being taken in side elevation, of a second preferred embodiment of the improved stretch-wrap film dispenser of this invention.
FIG. 5 is a side-elevational view of a third preferred embodiment of the improved stretch-wrap film dispenser of this invention, with some parts taken in central axial section.
FIG. 6 is an enlarged section taken generally along the line 6--6 of FIG. 5.
FIG. 7 is a central axial section through a fourth preferred embodiment of the improved stretch-wrap film dispenser of this invention, with parts broken away.
FIG. 8 is a longitudinal sectional view through the axis of a fifth preferred embodiment of the improved stretch-wrap film dispenser of this invention, with parts broken away.
FIG. 9 is an axial section through a sixth preferred embodiment of the improved stretch-wrap film dispenser of this invention, with parts broken away.
FIG. 10 is a side-elevational view of a seventh embodiment of the improved stretch-wrap film dispenser of this invention, with parts taken in central axial section and parts broken away.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The first preferred embodiment of the improved stretch-wrap film dispenser of this invention is generally indicated at 10 in FIG. 1. Portions thereof are shown in exploded position in FIG. 2, and one end thereof is shown in axial section in FIG. 3. Stretch-wrap film dispenser 10 comprises a roll of stretch-wrap film 12 on an elongated core 14. Core 14 is preferably an extruded PVC tube, or the like. Core 14 extends axially past the ends of film roll 12 on both ends thereof. Left end 16 and right end 18 are shown in FIG. 1, and the left end is shown in FIG. 3.
Left and right handles 20 and 22 are tubes which engage around the extended core 14 where it extends outward from the end of the film roll. The handles are freely rotatable on the core. Flanges 24 and 26 are respectively formed on the handles. Elastomeric brake washers 28 and 30 are respectively positioned between the flanges and the ends of the roll of stretch-wrap film. By thrusting the handles together, the flanges squeeze the brake washers against the roll, to increase the torque required to unwind film from the roll, and thus control film tension.
Tension member 32 is in the form of an elongate bar which has threads at least on the ends. Tension in the bar is transferred to the handle sleeves through nuts 34 and 36 which engage in discs 38 and 40 which are fixed in the outer ends of the handle sleeves. The handles are preferably of tubular thermoplastic stock, such as PVC, and the discs 38 and 40 may be of wood or cardboard which are held in place by glue and/or staples. By rotating the handles relatively to each other, the nuts acting on the threaded tension bar 32 move the handles 20 and 22 towards or away from each other to control the force on the brake washers to thus control the tension. Thus, clockwise rotation of either handle increases the tension and relative counter-clockwise rotation decreases the tension. The operator holds one handle in each hand and walks around the packages to be wrapped as a unit. The starting end of the film is tucked into the group of packages, and the operator walks around the group. He controls the tension as he walks around the group to assure that the packages are being wrapped with the proper stretch in the wrapping film. The tension can be constantly adjusted as he wraps the packages into a unit. It is the space between the ends 16 and 18 of the core 14 with respect to the discs 38 and 40 that permit the handles to move towards each other. Under the tension of tension rod 32, all of the tension forces are delivered to the brake washers 28 and 30.
The stretch-wrap film dispenser 42 is shown for one end of the structure. The two ends are identical, as was illustrated in the embodiment shown in FIG. 1. In the dispenser 42, film roll 44 is wound on core 46 which extends from both ends of the roll of stretch-wrap film. Handle 48 is one of two identical handles, one on each end of core 46. Handle 48 is freely rotatable on the extended portion of the core and has a cap 50 thereon. The cap 50 can be a polymer composition plug inserted in the end of handle 48 and secured therein by stapling and/or gluing or the like. Cap 50 has a threaded opening therein, which may be directly threaded into the cap or may be a threaded insert. Tension member 52 is a threaded rod, the same as tension member 32, and is threaded into the threaded openings in the two handles. Brake washer 54 is positioned between the outer end of core 46 and cap 50, and a similar brake washer is positioned on the other end of core 46. As the two handles on opposite ends of the core 46 are rotated, due to the threaded portions of the tension member, the handles move towards or away from each other. When they are rotated clockwise, the handles move towards each other and compress the brake washers against the ends of the core 46 to increase tension. As the operator holds the two handles and walks around the packages to be wrapped into a unit, he holds both of the handles and pulls the stretch-wrap film around the packages to cause tension therein. Tension can be continuously controlled by relative twisting or rotation of the handles to tighten or loosen the compression on the brake washers. Thus, the operator has continuous control as he wraps the packages into a unit.
FIGS. 5 and 6 illustrate the stretch-wrap film dispenser 58 which also employs relative spiral surfaces to control brake tension. Stretch-wrap film 60 is wound on core 62 which extends past the ends of the roll of film 60. Handles 64 and 66 are in the form of sleeves which are rotatably mounted on the extended ends of the tubular core. Flanges 68 and 70 are formed on the handles and are positioned towards the film roll. Brake washers 72 and 74 are positioned between the flanges and the roll of film 60. When the handles are moved towards each other, the brake washers are compressed to provide unrolling tension. Tension member 76 extends through the interior of core 62 and extends out past the ends thereof to engage both of the handles 64 and 66. The core 62, the tension member 76 and both of the handles 64 and 66 are preferably made of a fairly rigid thermoplastic extruded tubing, such as polyvinyl chloride. They are sized so that they can move with respect to each other without excessive spacing. Control of the tension by relative rotation of the two handles is accomplished by means of a spiral cam groove 78 on the interior of each of the handles. The groove 78 is shown in handle 66 in FIGS. 5 and 6, and a similar groove is provided in handle 68. Crosspin 80 extends through tension member 76, see FIG. 6, and extends into spiral cam groove 78. The sprial cam groove 78 is spiraled in the same sense as a screwthread so that rotation on the central axis causes relative axial movement. The two spiral cam groovs are in the same orientation so that when the handles are relatively rotated clockwise, the pressure on the brake washers is increasd to increase unwinding tension. Relative rotation in the counterclockwise direction causes decrease in the unwinding tension.
The stretch-wrap film dispenser 82 in FIG. 7 is similar to the structure of FIG. 5 but uses a screwthreaded bolt and nut instead of a spiral groove and pin. Film roll 84 is wound on extended core 86 which as a handle rotatably mounted on each end thereof, with handle 88 shown on the right end. The left end is symmetrically identical. Handle 88 carries flange 90 which compresses brake ring 92 between the flange and film roll. Tension member 94 extends between the two handles and carries a plug 96 in the end thereof. Bolt 98 has its head engaged behind plug 96 and has its screwthreaded outer end engaged in nut 100. Nut 100 is engaged in plug 102 in the outer end of the handle. In this way, the handles can be moved towards each other by providing tension through the tension member. This structure is very similar to the structure of FIG. 1 except that, in the case of dispenser 82, the tension member is partly formed of extruded tubing.
In the stretch-wrap film dispenser 104 illustrated in FIG. 8, the dispenser is illustrated as being configured for a larger standard core which is the same length as the roll of stretch-wrap film 108. Plug 110 is pressed into each end of the core 106 and is irrotatably held therein by means of axial ribs 112 on the outside of the plug. Plug 110 carries bearing tube 114 which is axially secured to the plug and serves as an extension thereof. Bearing tube 114 is sufficiently small that handle 116 is rotatably mounted on the exterior thereof. Flange 118 on the handle cooperates with brake washer 120 which lies adjacent the plug. Thus, axial movement of the handle towards the plug increases friction. Tension member 122 extends through the interior and engages in threaded plug 124 in the outer end of the handle. The other end of the dispenser 104 is similarly equipped. In this way, relative clockwise rotation of the handles causes an increase in tension by compressing the brake disc. The tension can be continuously controlled as the operator moves the roll of stretch-wrap film around the packages to be wrapped together.
The embodiments thus far described rely on screwthreads to control the force of the handles onto the brake washers. Relative rotation causes tightening. In the stretch-wrap film dispenser 126 shown in FIG. 9, a roll 128 is wound on an elongated core 130. One end of the roll and core is shown, and the other end is identical. The core extends out past the end of the roll and serves as a bearing upon which handle 132 rotates. The outer end of core 132 carries plug 134 while the outer end of handle 132 carries plug 136. Brake washers 138 and 140 are respectively positioned against the plugs. Compression spring 142 is positioned between the washers. An identical structure is positioned on the other end of core 130. When an axial inward force is applied, with the handles urged towards each other, the handles rotate and slide on the core and the axial compression force is felt by compression spring 142. This force is also applied to the two brake washers which engage against the plugs to cause rotary friction restraining rotation of the handle on the core. Thus, unwinding tension is controlled by inward axial force which appears on the brake wahsers through the springs.
The stretch-wrap film dispenser 144 of FIG. 10 is similar to the stretch-wrap film dispenser 10 of FIG. 1. Stretch-wrap film is wound into a roll 146 on core 148 which extends out of both ends of the film roll. Handles 150 and 152 are rotatably mounted on the extended ends of the core. Flanges 154 and 156 are formed on the handles at the end facing the film roll. Brake washers 158 and 160 are positioned between the flanges and the film roll. Axial force on the handles, urging them towards each other, increases the unwinding friction by compressing the brake washers. Plugs 162 and 164 are fixed in the outer ends of the handles, and tension spring 166 is attached to the plugs. The handles are rotatably and axially slidable on the extended ends of the core so that the tension of spring 166 applies an axial force to the handles in the direction towards each other to provide an axial force on the brake washers 158 and 160. Thus, as the operator holds the handles and travels around the packages to be wrapped into a unit, if he applies no axial force, the tension of the spring controls the winding tension of the stretch-wrap film. Of course, the operator can modify the stretch-wrap film tension by applying an inward axial force on the handles to increase the stretch-wrap film tension or an outward axial force on the handles to decrease the stretch-wrap film tension. Furthermore, tension spring 166 can be adjustably mounted so that the spring force can be adjusted and the force applied to the brake washers by the spring can be adjusted.
In each of the embodiments of the stretch-wrap film dispenser, the tubular members are extruded fairly rigid thermoplastic material, such as polyvinyl chloride. The fits are such as to permit rotational and axial freedom. The plugs are preferably made of cardboard or wood and can be stapled in place. The out-turned flanges on the handles in several embodiments can be thermoplastically formed of the original tubular thermoplastic material. Thus, each stretch-wrap film dispenser can be economically constructed and can be built as a throwaway device. Thus, there is no need for disassembly and rewinding of the core. With a throwaway device of that nature, wide use thereof can be enjoyed in many small production shops.
While the stretch-wrap film dispensers have been described as being carried around a stationary group of packages, it is clear that the group of packages can be rotated while the operator stands still, holding the dispenser. It is the relative rotation that is required for the stretch-wrapping operation.
This invention has been described in its presently contemplated best mode, and it is clear that it is susceptible to numerous modifications, modes and embodiments within the ability of those skilled in the art and wthout the exercise of the inventive faculty. Accordingly, the scope of this invention is defined by the scope of the following claims. | Stretch wrap film is wound on a mandrel or core which is longer than the roll of film to extend out of both ends. A rotatable handle is mounted on the core outboard of the film. Relative braking between the handle and core is adjusted by means of a screwthread which tightens a friction brake. The dispenser is carried around an article to be wrapped and the tension of the film is controlled by adjusting the brake by rotating its controlling nut. With a large core, an extension can be attached to a plug therein. Furthermore, instead of a spiral surface as on a nut and stud, a spring may be used to control brake force. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Benefit of provisional application 61/068,124 filed Mar. 5, 2008 is claimed.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] N/A
REFERENCE TO SEQUENCE LISTING, TABLE, COMPUTER PROGRAM
[0003] N/A
BACKGROUND OF THE INVENTION
[0004] The field of endeavor this invention is directed to a surgical instrument and a surgical knot tying aid, including but not limited to laparoscopic surgical knot tying. This instrument and technique will be of immense value in laparoscopic or endoscopic surgery and any surgery requiring tying knots in suture in a deep cavity. Instrument placement often makes knot tying extremely difficult even for the most experienced laparoscopic surgeons. Inexperienced surgeons struggle with learning to knot tie with standard techniques so much so that procedures requiring suturing and knot tying are considered advanced procedures. In laparoscopic surgery instruments are placed into a body cavity filled with gas. The instruments are placed through devices called ports, which allow the instruments to be taken in an out of the body without loss of the insufflated gas. This gas fills the cavity providing room to manipulate instruments and visualize tissues. These ports allow limited movement of the instruments in the body because there is an effective fulcrum at the point in which the skin is breached. This restriction coupled with limited visualization in the body on a flat monitor makes tying knots inside the body (Intracorporeal) very difficult. Typically the smaller the angle between the two instruments being used to tie, the more difficult knot tying becomes. This difficulty is further exacerbated when the cavity in which the surgery is being performed is very small as is the case when placing sutures in the pelvis as would be done in a laparoscopic prostatectomy, or culpopexy. A growing trend in laparoscopic surgery is single port surgery. In single port surgery multiple trocars are placed through a single small skin incision. The advantage is a much better cosmetic result, as there is only one small incision. Natural orifice surgery is another trend in modern laparoscopic surgery that results in no visible skin incision. The drawback of these surgical approaches is that surgical instruments must be introduced into the body very close together. This further restricts a surgeon's ability to manipulate the instruments and therefore increases the difficulty of performing a surgery that would be more easily accomplished with a standard laparoscopic or open approach. This increased difficulty and decreased range of motion of the surgical instrumentation necessitates new instrumentation that can help accomplish surgical tasks under more restrictive conditions. One of the most difficult tasks is intracorporeal knot tying. The modified needle driver and complementary method of use, claimed in this patent application, make knot tying easy and allow for unrestricted port placement. This is of particular advantage in laparoscopic applications where instrument placement is limited, as it is in single port surgery and natural orifice surgery, and in situations where suturing is necessary in small spaces like in the pelvis. With the modified needle driver, a knot can be easily tied even with two instruments placed so close together that they are essentially parallel. This allows for surgery previously requiring open procedures due to the difficult knot tying situations to be performed laparoscopically. In the growing trend in laparoscopic surgery known as single port surgery this modified needle driver will allow the use of standard suture and ligature placement where suturing was previously impossible. This opens possibilities for new procedures to be done with the single-port approach that previously were not possible due to the need for knot-tying.
[0005] Standard endoscopic knot tying is accomplished after a stitch has been placed with an instrument called a needle driver. A surgeons knot is formed by multiple square knots tied in a succession of half hitches. Each half hitch is called a throw. A throw is formed with the use of two grasping instruments, typically a needle driver and a tissue grasper or second needle driver. A suture with a curved needle attached to at least one end of the suture is placed through the tissue to be tied using the needle driver in the right hand to manipulate the needle and place it in the desired position. If a ligature is to be placed then an angled grasper is often placed behind the tissue to be ligated and the suture handed with a needle driver to the jaws of the angled grasper and then the suture is pulled behind the tissue. In either case the suture is pulled through the tissue to leave a short suture end of approximately two and a half centimeters and a long end of eight to ten centimeters. The suture is now in a position to form a knot. The long suture is grasped with the instrument in the left hand and then with a difficult combination of moves the long suture is wrapped around the tip of the right hand instrument to form one or two loops around the end of the instrument. The right hand instrument with the loops around the tip must then be used to grasp the short end of the suture. This short end is then pulled through the loops surrounding the tip of the instrument and the ends are pulled in opposite directions to snug the first throw of the knot. The next throw is typically formed in the same manor only with the wraps wound around the right hand instrument in the opposite direction as the wraps in the first throw. Subsequent throws are done in an alternating fashion, which allows the knot to snug down flat forming a square knot, which is more secure. A standard surgeons knot starts with a throw that has two wraps around the instrument because this facilitates the knot holding snug once it is pulled tight on the first throw. Sometimes a slipknot is formed by making two throws in the same direction. This accomplishes the same thing as a surgeons knot, allowing the knot to be secured snugly before locking throws are applied. The rate limiting and most difficult step is wrapping the suture around the tip of the right hand instrument and then keeping the wraps on the tip while maneuvering the instrument into a position to grasp the short end of the suture. To make a double wrap to form a surgeons knot is often impossible however it is often preferable to the slipknot because the slipknot can fail to slip and not allow the suture to be tightened appropriately.
[0006] The lap needle driver is typically 14 inches long with a working end comprised of two jaws, which approximate to hold a needle or grasp suture. The large distance between the hand piece and the working end, the reliance on a two dimensional monitor and the restricted movement secondary to ports and port placement make intracorporeal knot tying very difficult.
[0007] Many attempts to solve the problem of intracorporeal knot tying have been made. Most are too complex, cumbersome or slow, if they even work at all. Task specific devices such as the endo-stitch have limited applications and are single use as well as expensive. Knot pushers work but have many drawbacks, which keep them from being widely accepted. They require multiple instrument exchanges, which exposes the patient to increased risk of injury. They are slow to tie knots, and require very long sutures to be used, which are not available in all sizes. They increase the risk of tearing the suture out of delicate tissue. Intracorporeal knot tying aids are available but not widely accepted. Like the knot pusher they require multiple instrument exchanges with the added risk. Some advocate additional port sites for the tying aid. This also increases risk to, as well as scaring of the patient. Most surgeons prefer to minimize the number of port sites. Many other knot-tying devices have been patented but are not useful. The following examples illustrate the industry standard for laparoscopic needle drivers and the major differences between the modified needle driver, of claim one and some of the best attempts to improve laparoscopic needle drivers.
[0008] U.S. Pat. No. 5,242,458 held by Ethicon, Inc. (Somerville, N.J.) represents the industry standard laparoscopic needle driver. This is a typical design for most needle drivers in use today. It represents a standard jaw design with jaws that open approximately thirty degrees. This angle is not sufficient to control suture while knot tying nor is it designed to be.
[0009] U.S. Pat. No. 5,364,409 held by Ethicon, Inc. (Somerville, N.J.). This patent represents the basic laparoscopic needle driver employing a non-deployable shaft based accessory hook to capture suture and assist in tying. The key differences are that the hook is not deployable and retractable nor is it part of the jaw mechanism. This design for a non-deployable hook to aid in knot tying is not useful and is dangerous in practice because the hook would catch on tissue inadvertently. Knot tying with this configuration would be impeded because the hook is not retractable and would hinder the loops sliding off the instrument to form the knot. The hook for catching the suture would also catch on the seal in the trocar, impeding insertion and removal from the body cavity. This requires a second sleeve be employed to cover the hook to keep it from causing damage or impeding insertion and removal through the trocar. This requires added steps to knot tying and causes the instrument to have a wider shaft than the standard five millimeter.
[0010] U.S. Pat. No. 5,147,373 represents an attempt to ease knot tying by incorporating a second jaw into the shaft of a grasper or needle driver. This would allow for more control of the suture but the design is unnecessarily complex and would not be applicable to a standard five-millimeter diameter instrument. Other major disadvantages of this design include the necessity of a secondary control mechanism. This would slow the actual knot tying. The design claimed in claim one claims secondary control mechanism however the most useful example is the simplest with the jaw acting as the projection under direct control of the jaw mechanism. This allows the surgeon to focus on the task and not multiple controls. Claim one claims a radial projection to catch the suture as it slides over the shaft as it would be done in a standard knot tying procedure. This differs from any mechanism that would require actually grasping the suture with a secondary grasper of any design. The radial projection is an improvement over a secondary grasping mechanism because it does not require any extra steps be added to the knot tying procedure. The procedure using any secondary grasping mechanism would necessitate multiple added steps. The surgeon would have to release the jaw actuating mechanism, grasp the secondary mechanism, position suture in secondary jaw, grasp suture with secondary mechanism, move hand back to primary jaw mechanism, continue standard knot tying steps, then move hand back to secondary control, release secondary grasper, and finally finish remainder of standard knot tying steps. This is a lot of added complexity and time that is not necessary when using the claimed improved needle driver, which actually decreases the complexity of the knot tying procedure.
[0011] U.S. Pat. No. 5,601,578 Endoscopic suturing device 1997 United States Held by Miranic Investments Pty. Ltd. (Geelong, AU) This needle driver is similar in concept except the crucial difference is that the hook is not deployable and retractable. It would get in the way of manipulating the needle and tissue and could potentially be dangerous due to the ease in which tissue could be accidentally hooked and torn, especially while inserting or removing the instrument. The small diameter of the tip of the hook would also make inadvertent puncture of tissue a real and dangerous problem.
[0012] Tying knots through a single port approach with current technology is almost impossible. Intracorporeal knot tying is one of the most difficult techniques for laparoscopic surgeons to master and multiple inventions to simplify this difficult task have been designed. They all have one or more major drawbacks. Commonly, they necessitate exchanging instruments in and out of the access ports. This wastes time; increasing the time the patient must be under anesthesia and therefore increases the risk to the patient. Exchanging instruments also poses a risk to the patient by increasing the risk of accidental puncture or damage to other organs or structure during the exchange, as the visualization is difficult and instruments are not always visualized as they are exchanged. Risk of unintended and possibly unnoticed damage is increased with increased instrument exchanges. Another common drawback to knot tying devices is complexity. The more complex a mechanism the more likely it will malfunction. Surgical instrumentation must be reliable and durable. Single use mechanisms are not cost effective and complex mechanisms do not withstand the rigors of multiple washings and sterilization cycles. Many tying devices require set up for each suture or set up with device specific suture. This is once again time consuming and takes special training for surgeon and support staff. The majority of laparoscopic suturing and knot tying is still done with a traditional needle driver, which has not changed much in 40 years. Most surgeons want to tie the knot with the instrument they placed the suture with. They want the knot tying device to be versatile, and familiar. They do not want to have to learn complicated knot tying procedures or to use special suture that must be preloaded or set up for each stitch. Tying knots laparoscopically is difficult and learning how to do it takes a lot of time, practice, and aptitude. Not all laparoscopic surgeons master knot tying. The needle driver of claim one is simple, familiar and requires no new skill sets to be learned.
BRIEF SUMMARY OF THE INVENTION
[0013] A modification to a standard needle driver in the form of a deployable and retractable projection, which allows for complete control of suture while laparoscopically tying knots. This modification greatly simplifies and eases knot tying in laparoscopic surgery and opens up possibilities for suturing in single port surgery. The best example of this modification employs a mobile upper jaw, which is controlled with a standard hand-piece but is modified to open to an oblique angle when opened maximally. The lower jaw is stationary.
Advantages:
[0000]
1. The surgeon is able to tie knots easily without added steps
2. Knot tying is fast
3. There is no complex mechanism to fail
4. The needle driver is familiar to the surgeon because any style of needle driver can be modified to work with this concept
5. No secondary actuating mechanism is necessary
6. Makes knot tying in single port surgery easy
7. No instrument exchange is necessary to knot tie
8. Multiple knots may be formed with the same piece of suture material
9. Both running sutures and interrupted sutures may be placed and tied without need for extra instrumentation
10. Any suture material may be used
11. Suture does not have to be long to allow for tying outside the body as with knot pushers
12. The most delicate sutures may be tied
13. Maximum control over the tension placed on the knot is maintained
14. The movements required for the knot tying procedure are small and stay within the visual field of the surgeon
15. Needle driver is easily fashioned within the standard five-millimeter dimension.
EXPLANATION OF FIGURES
[0029] Illustrations are not intended to show all possible variations or limit the scope of invention, only to illustrate possible variations.
[0030] FIG. 1 shows exemplary example of jaw mechanism deployed for knot tying. It shows detail of modified jaw, opening greater than 90 degrees ( 11 ), tubular shaft ( 13 ), and suture ( 12 ).
[0031] FIGS. 2-7 show illustrations of knot forming technique using modified needle driver.
[0032] FIG. 2 shows detail of instrument tie step one, utilizing modified needle driver of claim 1 .
[0033] FIG. 3 shows detail of instrument tie step two, crossing long end of suture over modified needle driver of claim 1 to engage deployed projection.
[0034] FIG. 4 shows detail of instrument tie step three, looping the suture around the instrument in the non-dominant hand.
[0035] FIG. 5 shows detail of instrument tie step four, grasping short end of suture with modified needle driver, and retracting projection.
[0036] FIG. 6 shows detail of instrument tie step five, pulling short end of suture through loop (or loops) formed around modified needle driver.
[0037] FIG. 7 shows detail of instrument tie final step, ends of suture are pulled in opposite directions to snug knot. These steps form a single throw. These steps are repeated to form multiple throws.
[0038] FIGS. 8 , 9 & 13 - 15 . Exemplary variations of invention utilizing upper jaw to form projection on needle driver.
[0039] FIG. 8 shows one method by which jaw mechanism may be enabled to open to a wide enough degree to be effective as described invention of claim 1 . FIG. 8 shows closed position of mobile upper jaw and fixed lower jaw. Jaw mechanism is actuated by sliding of shaft, which is actuated by any standard hand-piece (not shown).
[0040] FIG. 9 shows open and closed position of jaw mechanism of FIG. 8 .
[0041] FIGS. 10-12 show one embodiment of linkage actuated non-jaw projection ( 1 ) actuated by same mechanism, which actuates opening and closing of grasping jaw.
[0042] FIGS. 13-15 show one embodiment of linkage-actuated embodiment of invention with projection formed by upper grasping jaw. This also illustrates that the invention may be applied to needle driver designed with “needle righting” jaws.
DETAILED DESCRIPTION OF THE INVENTION
[0043] Modification to a standard needle driver or grasper, which allows increased ease and precision of knot tying in standard laparoscopic or endoscopic procedures (here in just referred to as laparoscopic) and allows knot tying in previously impossible situations, for example single port surgery. The procedure for using modified needle driver to form a knot in suture material.
[0044] The ideal embodiment of the invention is a laparoscopic needle driver or grasper composed of hand-piece, five-millimeter tubular body, and jaw assembly with one fixed jaw and one mobile jaw. The mobile jaw opens much further than is standard, opening greater than ninety degrees. This upper jaw is the deployable and retractable projection used to control the suture. The jaws are controlled by standard hand-piece allowing for surgeon's personal preference, as there are multiple variations. The hand-piece may be modified by a change of angles and pivot placement such that there is an increase in the distance of the movement of the actuating bar that travels the barrel shaft, allowing for wider opening jaw than is usual. The pivot points and lever length of the jaw mechanism may also be modified to utilize a standard short actuator arm movement but translate that movement into a larger jaw movement.
[0045] The modified needle driver is unique because it incorporates deployable and retractable apparatus at the jaw-end, which is a projection from the midline of the central axis of the needle driver. This projection works in such a way as to allow a suture to catch on said projection, during knot tying procedure, which keeps the suture from sliding off the end of the instrument as the suture is wrapped around the instrument. This simplifies the most difficult and rate limiting step of forming a knot in a suture. The projection is actuated by the operator and when not deployed lays in such a way that a suture may easily slide off the end of the instrument without catching during the final step of the knot tying. This is key to the invention as others have designed needle drivers with a permanent projection to control the suture, however it becomes more of a hindrance than help because it is not retractable and causes the suture to hang up during the final step of the knot tie.
[0046] Furthermore the projection may be actuated by either the mechanism, which controls the jaws of the needle driver, or by separate control mechanism. The preferred embodiment of the mechanism is incorporated into the jaws designed to hold a needle or tissue. This is accomplished by making one of the jaws of the modified needle driver open much further than is standard. An angle formed between the axial midline and the projection of 90 degrees or greater would give the greatest ease of capturing the suture for knot tying. Mechanism must be fully retractable to allow introduction of endoscopic instrument through access ports and to minimize chance of accidentally hooking tissue and causing harm to the patient.
[0047] Method for using modified needle driver to perform an instrument-tie. With a standard suture material positioned to tie, start with one end of the suture held in the jaws of a grasper or second needle driver in the operator's non-dominant hand ( FIG. 2 ). The operator then using his/her dominant hand lays the distal end of the modified needle driver on top of the suture being grasped by the non-dominant hand ( FIG. 2 ). With the mechanism deployed on the modified needle driver, the operator then crosses the suture held with the non-dominant hand over top of the shaft of the modified needle driver proximal to the projected mechanism ( FIG. 3 ). This will catch the suture as it slides distally along the shaft of the modified needle driver and allow the suture to easily be looped around the distal end of the instrument ( FIG. 4 ). Multiple loops of suture may be made around the modified needle driver by repeating these steps. The short end of suture may now be grasped by the modified needle driver ( FIG. 5 ). The projection retracts and the short end of suture is pulled through the loop or loops of suture formed around end of modified needle driver, forming one throw of a knot ( FIGS. 6&7 ). To form square knots a second modified needle driver may be used and knot tied by wrapping around the instrument in the non- dominant hand. Additionally, a one-handed square knot may be formed, by alternating direction the loop is placed around the instrument. First placing modified needle driver on top of the suture to form the first throw and then turning the modified needle driver over and placing the suture held by the non-dominant hand on top of the modified needle driver, then crossing underneath with the non-dominant held instrument, catching the suture on the mechanisms projection underneath and easily wrapping around the instrument's end in the opposite direction from the first throw. The two instruments are then used to tighten the knot by pulling the suture ends in opposite direction ( FIG. 7 ). Any standard suture material may be used and may be tied with or without needle attached.
[0048] Variation to method utilizing needle driver fitted with rotational shaft. The modified needle driver is placed over suture as described above and suture end is moved across the shaft with the non-dominant hand in such a way that the deployed mechanism can catch the taught suture and pull it around the end of the instrument as it is rotated forming a loop each rotation. The short suture end is then grasped as previously described and the knot is finished as with non-rotational shaft needle driver.
[0049] This invention is distinct from other needle drivers because none have ever incorporated a simple deployable and retractable projection to control suture for the purpose of knot tying. Today the typical needle driver opens to approximately 30 degrees, nowhere near the 90 degrees or more needed to maximally control the suture in the ideal embodiment. Standard knot tying methods entail closing the jaws of the needle driver during the rate-limiting step of encircling the suture around the instrument. This new method uses an open jaw or deployed secondary projection to control the suture during this critical step in knot tying. | A modification to a standard needle driver in the form of a deployable and retractable projection at the working end of the needle driver with which the operator can control the suture in order to facilitate tying a knot in the suture. This modification solves the difficult problem of controlling the suture during the rate-limiting step of knot tying allowing for faster, easier knot tying in laparoscopic and single port surgery. | 0 |
TECHNICAL FIELD
This invention pertains to blowers for pneumatically influencing fibers. In one of its more specific aspects, this invention pertains to annular blowers suitable for attenuating fibers that have been centrifuged by a rotating spinner from a liquid. A particular application for this invention is in the attenuation of glass fibers.
BACKGROUND OF THE INVENTION
Methods and apparatus for forming glass fibers in a rotary fiberizer process are well-known. In general, a molten glass stream is fed into a spinner which revolves at high speed. The spinner has a substantially open top, a circumferential side wall containing a plurality of holes, and a substantially solid bottom surface. As the spinner revolves, molten glass is centrifuged through the holes in the side wall, forming fibers.
Positioned circumferentially around the outside of the spinner is an annular blower which typically comprises an annular casing defining an annular chamber, a gas inlet port for supplying a gas to the annular chamber, and an annular gas outlet port on the inside circumference of the blower from which port gas emerges to pneumatically influence the centrifuged (primary) fibers. This pneumatic influence involves attenuating the primary fibers to form the final (secondary) fibers of smaller diameter than the primary fibers. The attenuation is accomplished through the drag force imparted to the primary fibers by the gas from the blower.
The outlet port is shaped to direct the gas in a substantially downward direction so that the primary fibers are turned downward, and the secondary fibers formed are inherently arranged into a downwardly moving annular array or veil. The major axis of this veil substantially coincides with the axis of rotation of the spinner. The outlet port usually comprises a series of discrete slots equally spaced around the inside circumference of the blower. The gas used is usually air, supplied by an air compressor.
The pneumatic influence may be confined to turning the primary fibers downward where no attenuation into secondary fibers is desired.
Annular blowers may be used for other purposes in the glass fiber forming process. As an example, it may be desirable to control the shape or movement of the veil as it descends downward from the spinner.
In any fluid flow device, energy losses occur between the fluid inlet and fluid outlet points. These losses are exacerbated if turbulent flow is present. In a conventional annular blower, a jet of gas flows from each slot in the blower annular outlet port, and a sole gas inlet port supplies the gas to the manifold. Accordingly, gas flows concurrently in both clockwise and counterclockwise directions in the annular chamber and turbulent flow conditions in the annular chamber result. Energy losses are excessive, and jet velocities fluctuate and are disparate jet-to-jet. These turbulent jet flow conditions cause the microstructure of a fiber to vary along the length of the fiber, resulting in a weaker fiber than is formed by a laminar flow jet. Additionally, fiber attenuation efficiency is higher with laminar flow jets than with turbulent flow jets.
The effect of two-directional flow is particularly evident at the confluence of the clockwise and counterclockwise flows at the location diametrically opposite the gas inlet port. Turbulence at this confluence is high, and discrete jet velocities are low and variable. The jet velocity profile at the confluent circumferential segment of the blower shifts to-and-fro in an oscillating (dancing) fashion. Fiber veils bulge, part, and dance in response to the confluent influence. Variations in pneumatic influence on primary fibers can result in production of an undesirably wide range of secondary fiber diameters and a malformed or badly controlled fiber veil. Even with a substantially continuous slot, two-directional flow can result in flow velocity disparities and turbulence detrimental to forming uniform fibers and to fiber veil shape and veil control.
This invention provides the means to uniform blower jet velocities and secondary fiber diameters, minimize fluid turbulence in the annular chamber, control the jet velocity profile, minimize energy consumption, and control the shape and oscillation characteristics of the fiber veil.
STATEMENT OF THE INVENTION
According to this invention, there is provided an annular blower for pneumatically influencing fibers which comprises an annular casing defining an annular manifold, a gas outlet port, and a baffle in the annular chamber to direct most of the gas in one circumferential direction in the annular chamber, thereby minimizing turbulence and velocity fluctuations in gas flow from the outlet port around the circumference of the blower.
In one embodiment of the invention, the outlet port is a substantially continuous slot.
In the preferred embodiment of the invention, the outlet port is a series of slots.
In the preferred embodiment of the invention, the baffle directs all gas flow in one circumferential direction.
In the preferred embodiment of the invention, the unidirectional baffle allows gas to flow past the baffle as a circumferential circuit is completed.
In another embodiment of the invention, the baffle is adjustable to permit flow over a range of from all in one circumferential direction to all in the opposite circumferential direction.
In another embodiment of the invention, the baffle allows flow in one direction only and allows no flow past the baffle as a circumferential circuit is completed.
In the preferred embodiment of the invention, the baffle is keyed to the inlet port for location purposes.
In another embodiment of the invention, vanes are employed in the manifold to direct and uniform gas flow.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic cross-sectional elevation view of a conventional spinner and blower.
FIG. 2 is a schematic elevation view of a conventional spinner, blower and forming chain showing the forming and collection of a fiber veil.
FIG. 3 is a plan view of a blower with the baffle of the invention installed, and blower top removed.
FIG. 4 is a perspective view of the baffle.
FIGS. 5a, 5b, 5c, 5d, 5e, 5f, and 5g are plan views of additional baffle embodiments.
DESCRIPTION OF THE INVENTION
This invention is described in terms of a process for manufacturing glass fibers. The invention is suitable for use in processes for manufacturing fibers from other materials as well, particularly inorganic materials such as rock, slag and basalt. The invention is described in terms of the best mode without meaning it to be limited thereto.
As shown in FIGS. 1 and 2, a stream of molten glass 2 is fed into spinner 4 which revolves at high speed. The molten glass is caused by centrifugal force to pass through holes 6 in spinner circumferential side wall 8 forming primary fibers 10.
An annular blower comprising a casing 12 defining an annular chamber 16 is positioned circumferentially around the spinner. Gas flow 14 is supplied to the annular chamber 16 through gas inlet port 18. Gas emerges from the blower through circumferential gas outlet port 20. This outlet port preferably comprises a series of discrete slots 22 and is shaped to direct the gas in a substantially downward direction. When the outlet port comprises discrete slots, the gas flow will initially be in the form of discrete jets. Other types of outlet port openings, such as a continuous slot, may be used. The gas impinges the primary fibers, turning them downward, attenuating the primary fibers into secondary fibers 24, and urging the secondary fibers toward forming chain 26 where they are collected into pack 28. The preferred gas is air, although other types of gas such as steam may be used.
Because of the annular shapes of the spinner side wall and the blower gas outlet port, the secondary fibers are inherently arranged into annular veil 30. This veil is a dynamic array, continuously travelling downward as a secondary fibers are generated from primary fibers by the gas emanating from the blower as outlet port.
Although it can be located anywhere in the annular chamber, angular unidirectional bypass baffle 32 as shown in FIGS. 3 and 4 is preferably located at the situs of the gas inlet port and is shaped and positioned to cause gas to move substantially in a single direction, preferably in the circumferential direction in which the spinner is rotating. As the gas completes a circuit through the annular chamber, it will bypass the angular unidirectional bypass baffle and continue its circumferential course.
Although gas directing members such as baffles can be any shape, the angular unidirectional bypass baffle is preferably formed to have a long leg 32a, a short leg 32b, and a base 32c. The base can be made to be substantially the same shape as the gas inlet port and to fit loosely into the gas inlet port for location purposes. The downstream leg of the baffle is the longer of the two legs so that the baffle will rotate in the gas inlet port and thrust the upstream (and shorter) leg against the inside of the casing 12 to effect substantially unidirectional gas flow in the annular chamber.
It may be useful to locate additional baffles in the annular chamber to function as vanes. These vanes, straight 46 or arcuate 48, shown in FIG. 5g, may be used to direct and uniform gas flow in the annular chamber, minimize turbulence, and adjust the jet velocity profile around the circumference of the blower.
The height of the baffles is generally the same as the height of the annular chamber, but preferably with a small clearance between the top of the baffle and the top of the chamber to allow the baffle to rotate into the working position. The baffles are shaped generally to conform to the cross-sectional shape of the annular chamber, where it is desired to inhibit the gas from flowing between the baffle and the casing. For example, in the preferred embodiment shown in FIG. 3, the legs of the baffle conform substantially to the upper and lower surfaces of the annular chamber, and the end of the short leg conforms substantially to the sidewall of the casing so that the gas can flow in only one direction. The gas is inhibited from flowing over, under, or around the short leg, and over or under the long leg.
Examples of other possible baffle embodiments are shown:
FIG. 5a shows a horseshoe unidirectional bypass baffle 34 which permits unidirectional gas flow to flow past the baffle as a circumferential circuit through the annular chamber is completed.
FIG. 5b shows a solid unidirectional baffle 36 which prohibits unidirectional gas flow from flowing past the baffle as a circumferential circuit through the annular chamber is completed.
FIG. 5c shows a foraminous bidirectional baffle 38 which permits regulation of the ratio of volumes of clockwise to counterclockwise gas flows by selection of baffle foramity.
FIG. 5d shows an angular bidirectional bypass baffle 40 which permits regulation of the ratio of volumes of clockwise to counterclockwise gas flows by selection of angular relationship of baffle legs, and orientation of baffle in the annular chamber, and permits gas flow in either circular direction past the baffle.
FIG. 5e shows an angular bidirectional baffle 42 which does not permit gas flow past the baffle.
FIG. 5f shows an adjustable angular baffle 44 which permits changing the orientation of the baffle in the annular chamber with a through-blower adjustment device such as shaft-and-handle 50 without disassembling the blower to access the baffle.
FIG. 5g shows two vane baffles, straight 46 and arcuate 48, which permit smoothing the gas flow in the annular chamber.
It can be seen that various combinations of baffle embodiments may be useful in controlling fiber forming and veil shape and oscillation. For example, vane baffles may be used alone or with other baffle embodiments, and the adjustable baffle fixture may be used with any bidirectional baffle or the vane baffles.
It is possible to fix, such as by welding, the short leg of the angular unidirectional bypass baffle to the inside of the casing so as not to depend on gas flow influence to rotate the baffle and hold the short leg against the casing. It can be seen that unidirectional baffles can be shaped to direct gas flow in either circumferential direction.
It is evident from the foregoing that various adjustments and modifications can be made to the apparatus of this invention. Such, however, are within the scope of the invention.
INDUSTRIAL APPLICABILITY
This invention will be found useful in the production of glass fibers for such uses as thermal insulation and acoustical insulation products. | An annular blower which has an internal baffle. The blower is used to attenuate glass fibers centrifuged from a spinner in a rotary fiberizer process. The internal baffle directs and uniforms gas flow in the blower and decreases turbulent flow conditions in the gas flowing from the periphery of the blower. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of International Application No. PCT/CN2009/074957, filed on Nov. 16, 2009, which claims priority to Chinese Patent Application No. 200810217322.6, filed on Nov. 14, 2008, both of which are hereby incorporated by reference in their entireties.
FIELD OF THE INVENTION
The present invention relates to the field of mobile communication technologies, and in particular, to a method and base station for sending information.
BACKGROUND OF THE INVENTION
Power consumption of a mobile terminal is always a bottleneck of mobile communication technologies. To reduce battery consumption, a terminal that carries out a non-real-time service generally employs a discontinuous reception (DRX) mode. When the service data received by the terminal does not arrive continuously, but arrives with regular periods, a DRX period adaptable to the service data can be configured on the terminal according to this service characteristic, namely, the characteristic of regular arrival of the service data. The DRX period involves two states: DRX receiving state and DRX sleep state. When the terminal is in the DRX receiving state, the terminal starts the transceiver to monitor the service data and control information sent by the base station, and the pilot and broadcast information periodically sent by the base station. When the terminal is in the DRX sleep state, the terminal shuts down the transceiver, and stops monitoring the service data and control information sent by the base station, and the pilot and broadcast information periodically sent by the base station.
A Femto cell is a solution to extending indoor coverage of mobile communication. A Femto cell is installed in a small coverage environment, in which a user initiates voice or data calls through a mobile device such as a mobile phone or a notebook computer. The Femto cell transmits the voice or data calls initiated through the mobile phone or notebook computer to a 3 rd Generation (3G) core network which is based on a standard interface. The home access point of a Femto cell is capable of plug-and-play and connectable to any existing Internet Protocol (IP)-based transport networks, and may take the place of a fixed bandwidth access device of households or small enterprises. Therefore, a Femto cell is also known as a home base station.
SUMMARY OF THE INVENTION
Embodiments of the present invention provide a method and base station for sending information. Through the technical solution put forward herein, the base station employs a discontinuous transmission (DTX) mode to save time-frequency resources, reduce interference on neighboring cells, and reduce the power consumption.
According to one aspect, a method for sending information is provided, where the method includes:
obtaining a DRX parameter of a terminal;
determining a DTX parameter of a base station according to the DRX parameter; and
sending pilot and broadcast information periodically according to the DTX parameter.
According to another aspect, a base station is provided, where the base station includes:
an obtaining module, configured to obtain a DRX parameter of a terminal; and
a determining module, configured to determine a DTX parameter of the base station according to the DRX parameter.
In a home base station environment, after the base station obtains the DRX parameter of the terminal, the base station determines the DTX parameter of the base station according to the DRX parameter, and sends pilot and broadcast information periodically according to the DTX parameter. After the base station enters the DTX mode, if all user terminals served by the home base station are in the DRX sleep mode, the base station also enters the DTX sleep period. That is, the base station sends no pilot or broadcast information and shuts down the transceiver, thus saving power and time-frequency resources, reducing interference on neighboring cells, and reducing the power consumption.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram of a flowchart of a method for sending information according to one embodiment of the present invention;
FIG. 2 is a schematic diagram of a flowchart of a method for sending information according to another embodiment of the present invention;
FIG. 3 is a schematic diagram of DRX parameter of terminal 1 that are with the same period according to another embodiment of the present invention;
FIG. 4 is a schematic diagram of DRX parameter of terminal 2 that are with the same period according to another embodiment of the present invention;
FIG. 5 is a schematic diagram of DRX parameter of terminal 3 that are with the same period according to another embodiment of the present invention;
FIG. 6 is a schematic diagram about how a base station adjusts the base station's own DTX transmitting period and sleep period according to another embodiment of the present invention;
FIG. 7 is a schematic diagram of DRX parameter of terminal 1 that are with the same bias according to another embodiment of the present invention;
FIG. 8 is a schematic diagram of DRX parameter of terminal 2 that are with the same bias according to another embodiment of the present invention;
FIG. 9 is a schematic diagram of DRX parameter of terminal 3 that are with different biases according to another embodiment of the present invention;
FIG. 10 is a schematic diagram about how a base station adjusts biased DRX parameter of terminal 2 according to another embodiment of the present invention;
FIG. 11 is a schematic diagram about how a base station adjusts the base station's own DTX transmitting period and sleep period according to another embodiment of the present invention;
FIG. 12 is a schematic diagram of a flowchart of a method for sending information according to another embodiment of the present invention;
FIG. 13 is a schematic diagram of DRX parameter of terminal 4 according to another embodiment of the present invention;
FIG. 14 is a schematic diagram of DRX parameters of terminal 5 according to another embodiment of the present invention;
FIG. 15 is a schematic diagram of DRX parameter of terminal 6 according to another embodiment of the present invention;
FIG. 16 is a schematic diagram of DRX parameters of terminal 4 that are adjusted by a base station according to another embodiment of the present invention;
FIG. 17 is a schematic diagram of DRX parameter of terminal 5 that are adjusted by a base station according to another embodiment of the present invention;
FIG. 18 is a schematic diagram of DRX parameter of terminal 6 that are adjusted by a base station according to another embodiment of the present invention;
FIG. 19 is a schematic diagram of how a base station determines the base station's own DTX transmitting period and sleep period according to DRX parameter adjusted for all terminals according to another embodiment of the present invention;
FIG. 20 a is a schematic diagram of a structure of a base station according to an embodiment of the present invention;
FIG. 20 b is a schematic diagram of another structure of a base station according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE EMBODIMENTS
To make the objectives, technical solution and merits of the present invention clearer, the following describes the embodiments of the present invention in more detail with reference to the accompanying drawings. Evidently, the embodiments described herein are only part of rather than all of the embodiments. All other embodiments, which can be derived by those skilled in the art from the embodiments given herein without creative effort, shall fall within the protection scope of the present invention.
When all terminals are in the DRX mode, the base station enters the DTX mode, thus saving power and time-frequency resources reducing interference on neighboring cells and reducing the power consumption.
FIG. 1 is a schematic diagram of a flowchart of a method for sending information according to one embodiment of the present invention. The method includes the following steps.
101 : Obtain a DRX parameter of a terminal.
102 : Determine a DTX parameter of a base station according to the DRX parameter.
103 : Send pilot and broadcast information periodically according to the DTX parameter.
Through the foregoing steps, time-frequency resources are saved, interference on neighboring cells is reduced, and power consumption is reduced.
The step of determining a DTX parameter of the base station according to the DRX parameter includes:
adjusting or confirming the DRX parameter of the terminal; and
determining DTX transmitting period and DTX receiving period of the base station according to the adjusted or confirmed DRX parameter.
Before adjusting or confirming the DRX parameter of the terminal, the method includes the following contents.
The base station confirms the DRX parameter of the terminal if the following conditions are fulfilled: The DRX period parameter of the terminal is the same as that of other terminal which is already in the DRX mode, and DRX bias parameter of the terminal is different from the DRX bias parameter of other terminal which is already in the DRX mode; or, the DRX period parameter of the terminal is different from that of other terminal which is already in the DRX mode.
The base station needs to adjust DRX bias parameter of the terminal, namely, map the DRX bias of the terminal to a DRX bias not occupied by other terminal, if the following conditions are fulfilled: The DRX period parameter sent by the terminal is the same as that of other terminal which is already in the DRX mode, and the DRX bias parameter of the terminal is also the same as that of other terminal which is already in the DRX mode.
The base station may also adjust the periods and DRX biases parameter of all terminals uniformly to a continuous time segment, so that all terminals have the same DRX period, and that the DRX biases of all terminals are adjacent to each other but not overlapped.
The content of determining the DTX transmitting period and receiving period of the base station according to the adjusted or confirmed DRX parameter includes that:
the base station adjusts its own DTX transmitting period and sleep period according to the adjusted or confirmed DRX parameter of all terminals, so that receiving periods of all terminals fall within the transmitting period of the base station.
In a home base station environment, after the base station obtains the DRX parameter of the terminal, the base station determines the DTX parameter of the base station according to the DRX parameter, and enters the DTX mode. The base station sends pilot and broadcast information periodically within the DTX transmitting period of the base station according to the DTX parameter. When all users served by the home base station are in the DRX sleep mode, the base station enters the DTX sleep mode. That is, the base station sends no pilot or broadcast information and shuts down the transceiver, thus saving power and time-frequency resources, reducing interference on neighboring cells, and reducing the power consumption.
FIG. 2 is a schematic diagram of a flowchart of a method for sending information according to another embodiment of the present invention. The method includes the following steps.
201 : The terminal decides to enter the DRX mode according to characteristic of the received service data.
When the service data received by the terminal does not arrive continuously, but arrives with regular and periods, the terminal configures a DRX period adaptable to the service data according to the characteristic of regular and periodical arrival of the service data.
202 : The terminal sends a DRX mode request message that carries a DRX parameter to the base station.
The request message carries parameter such as the DRX period and the DRX bias of the terminal.
203 : The base station adjusts or confirms the DRX parameter of the terminal, and determines the DTX transmitting period and DTX sleep period of the base station according to the adjusted or confirmed DRX parameter.
The base station receives the period parameter and the DRX bias parameter sent by the terminal, and compares the received period parameter and the DRX bias parameter.
The base station does not need to adjust, but only needs to confirm, the period parameter and the DRX bias parameter, if the following conditions are fulfilled: The DRX period parameter of the terminal is the same as that of other terminal which is already in the DRX mode, and the DRX bias parameter of the terminal is different from that of other terminal which is already in the DRX mode; or, the DRX period parameter of the terminal is different from that of other terminal which is already in the DRX mode. The details are described below:
FIG. 3 , FIG. 4 , and FIG. 5 respectively show terminal 1 , terminal 2 and terminal 3 that are in the DRX mode. The period parameter is the same but the DRX bias parameter varies with terminal 1 , terminal 2 and terminal 3 . The base station does not adjust, but confirms, the DRX period parameter and the DRX bias parameter of the terminals.
The base station needs to adjust the DRX bias of the current terminal, namely, map the DRX bias of the current terminal to the DRX bias not occupied by other terminal, if the following conditions are fulfilled: The DRX period parameter sent by the terminal is the same as the period parameter of other terminal which is already in the DRX mode, and other DRX bias parameter of the current terminal is also the same as the DRX bias parameter of the terminal which is already in the DRX mode. The details are described below.
FIG. 7 , FIG. 8 , and FIG. 9 show respectively terminal 1 , terminal 2 and terminal 3 that are in the DRX mode. The DRX bias parameter of terminal 1 and terminal 2 are both “1”. Therefore, the DRX bias parameter of terminal 2 needs to be adjusted so that it is different from the DRX bias parameter of terminal 1 which is already in the DRX mode. As shown in FIG. 10 , the DRX bias parameter of terminal 2 is adjusted from “1” to “3”.
If the base station needs to only confirm the period parameter and the DRX bias parameter of the terminal, the base station adjusts its own DTX transmitting period and DTX sleep period according to the DRX parameter of all terminals, so that the receiving periods of all terminals fall within the transmitting period of the base station, as shown in FIG. 6 .
If the base station needs to adjust the period parameter and the DRX bias parameter of the terminal, the base station adjusts its own DTX transmitting period and DTX sleep period according to the adjusted DRX period parameter and the DRX bias parameter of all terminals, so that the receiving periods of all terminals fall within the transmitting period of the base station, as shown in FIG. 11 .
If any terminal is in the DRX receiving period, the base station is in the DTX transmitting period; when all terminals are in the DRX sleep period, the base station enters the DTX sleep period.
204 : The base station sends an acknowledgement message that carries the adjusted or confirmed DRX parameter.
The base station sends a DRX mode acknowledgement message to the terminal. The message carries the adjusted or confirmed a DRX parameter such as the period and the DRX bias.
205 : The terminal enters the DRX mode.
After receiving the acknowledgement message sent by the base station, the terminal enters the DRX mode according to the DRX period parameter and the DRX bias parameter carried in the acknowledgement message.
206 : The base station enters the DTX mode, and sends pilot and broadcast information periodically within the DTX transmitting period of the base station.
The base station enters the DTX mode according to the adjusted or confirmed DRX parameter of all terminals. If any terminal is in the DRX receiving period, the base station is in the DTX transmitting period.
When the terminal is in the DRX receiving period and the base station is in the DTX transmitting period, the base station sends service data and control information to the terminal, and sends pilot and broadcast information periodically.
When all terminals are in the DRX sleep period, the base station enters the DTX sleep period, shuts down the transceiver, stops sending data, and buffers the service data and control information. When the terminal gets into the DRX receiving period, the base station resumes sending of the buffered service data and control information. The base station only needs to adjust or confirm the DRX period parameter and the DRX bias parameter of each terminal simply without additional operations like adjusting the period or bias, thus saving power and time-frequency resources.
FIG. 12 is a schematic diagram of a flowchart of a method for sending information according to an embodiment of the present invention. The method includes the following steps:
Steps 1201 and 1202 are respectively similar to steps 101 and 102 in the previous embodiment.
1203 : The base station adjusts the periods and bias parameter of all terminals uniformly so that they fall within a continuous time segment, and determines the DTX transmitting period and sleep period of the base station according to the adjusted DRX parameter.
The base station adjusts the DRX period of each terminal to the same value, and adjusts the DRX period parameter and the DRX bias parameter of all terminals, so that they fall within a continuous time segment, and that the biases of all terminals are adjacent to each other but not overlapped. The details are described below:
FIG. 13 , FIG. 14 , and FIG. 15 respectively show terminal 4 , terminal 5 and terminal 6 that are in the DRX mode. The base station adjusts the DRX periods of terminal 4 , terminal 5 and terminal 6 to the same value, and adjusts the DRX period parameter and the DRX bias parameter of all terminals, so that they fall within a continuous time segment, and that the biases of all terminals are adjacent to each other but not overlapped. The adjusted DRX biases of terminal 4 , terminal 5 and terminal 6 are respectively shown in FIG. 16 , FIG. 17 and FIG. 18 .
The base station adjusts its own DTX transmitting period and DTX sleep period according to the adjusted DRX period, so that the receiving period of each terminal falls within the DTX transmitting period of the base station, and that the DTX sleep period of each terminal falls within the DTX sleep period of the base station. The adjustment is detailed in FIG. 19 .
Steps 1204 , 1205 and 1206 are respectively similar to steps 104 , 105 and 106 in the previous embodiment.
The base station performs uniform adjustment according to the DRX period and the DRX bias of each terminal so that the DRX receiving period of each terminal falls within the DTX transmitting period of the base station. When all terminals are in the DRX sleep period, the base station enters the DTX sleep period, shuts down the transceiver, stops sending data, and buffers the service data and control information. When the terminal gets into the DRX receiving period, the base station resumes sending of the buffered service data and control information, which saves power and time-frequency resources, reduces interference on neighboring cells and avoids starting up and shutting down the transceiver frequently on the base station side.
A home base station is provided in the fourth embodiment of the present invention.
As shown in FIG. 20 a , the home base station includes:
an obtaining module 21 , configured to obtain a DRX parameter of a terminal; and
a determining module 22 , configured to determine a DTX parameter of the base station according to the DRX parameter obtained by the obtaining module.
As shown in FIG. 20 b , the determining module includes a first processing module 221 , a second processing module 222 , and a first determining module 223 . The details are described below:
The first processing module 221 is configured to adjust or confirm the DRX parameter of the terminal.
The second processing module 222 is configured to determine the DTX parameter of the base station according to the DRX parameter adjusted or confirmed by the first processing module.
The first determining module 223 is configured to adjust the DTX transmitting period and sleep period of the base station according to the adjusted or confirmed DRX period parameter and the DRX bias parameter, so that the receiving periods of all terminals fall within the transmitting period of the base station.
The first processing module 221 includes:
a first confirming module 2211 , configured to confirm the DRX parameter of the terminal if the following conditions are fulfilled: the DRX period parameter of the terminal is the same as the period parameter of other terminal which are already in the DRX mode, and the DRX bias parameter of the terminal is different from the bias parameter of other terminal which are already in the DRX mode; or the DRX period parameter of the terminal is different from the period parameter of other terminal which are already in the DRX mode;
a first adjusting module 2212 , configured to adjust the DRX parameter of the terminal if the following conditions are fulfilled: The DRX period parameter of the terminal is the same as the period parameter of other terminal which are already in the DRX mode, and the DRX bias parameter of the terminal is the same as the DRX bias parameter of other terminal which are already in the DRX mode; and
a second adjusting module 2213 , configured to adjust the DRX periods of all terminals to the same value and adjust the DRX biases of all terminals to be adjacent to each other but not overlapped.
In a home base station environment, after obtaining the DRX parameter of the terminal, the base station determines the DTX parameter of the base station according to the DRX parameter, and enters the DTX mode. When all user terminals served by the home base station are in the DRX sleep mode, the base station also enters the DTX sleep period. That is, the base station sends no pilot or broadcast information and shuts down the transceiver, thus saving power and time-frequency resources, reducing interference on neighboring cells, and reducing the power consumption.
After reading the foregoing embodiments, those skilled in the art are clearly aware that the embodiments of the present invention may implemented through hardware, or, preferably in most circumstances, through software in addition to a necessary universal hardware platform. Therefore, the essence or contributions to the prior art of the technical solution under the present invention may embodied in a software product. The software product may stored in computer-readable storage media and incorporate several instructions for instructing a computer device (for example, a personal computer, a server, or a network device) to execute the method specified in any embodiment of the present invention.
Although the invention is described through some exemplary embodiments, the invention is not limited to such embodiments. It is apparent that those skilled in the art may make modifications and variations to the invention without departing from the spirit and scope of the invention. The invention is intended to cover the modifications and variations provided that they fall within the protection scope defined by the following claims or their equivalents. | The present invention relates to mobile communication technologies, and in particular, to a method, base station and system for sending information. The method includes: obtaining discontinuous reception (DRX) parameter of a terminal; determining discontinuous transmission (DTX) parameter of the base station according to the DRX parameter; and sending pilot and broadcast information periodically according to the DTX parameter. The technical solution under the present invention saves time-frequency resources, reduces interference on neighboring cells, and saves electric power. | 8 |
FIELD OF THE INVENTION
The present invention pertains to a process for shortening a fabric-side hook thread with a thread-carrying needle, with a hook cooperating with the thread-carrying needle, with a take-up lever, with at least one feed element, and with a thread-cutting device with a catch thread device.
BACKGROUND OF THE INVENTION
The thread-cutting process usually takes place as follows in a sewing machine equipped with a thread-cutting device: The sewing machine is stopped at the end of the seam with the needle in the lower position. The sewing machine is then driven briefly once again, in the course of which the arm shaft performs half a revolution and the hook a full revolution, and the take-up lever assumes the top dead center of its path of movement. In the course of this half revolution of the arm shaft, the catch thread device of the thread-cutting device performs a catching or separating movement, by which the threads to be cut are caught, during the time at which the hook has widened the needle thread loop. The cutting of the threads proper takes place only at the end of the half revolution of the arm shaft, when the take-up lever is stopped at the top dead center of its path of movement.
Since no sewing stitch formed by the looping of the hook and needle threads is formed by the thread cutting, the fabric-side needle thread end therefore emerges from the fabric after the thread cutting at the site of the last insertion of the needle, while the hook thread end hangs down from the fabric at the site of the last complete stitch. Since these two points are spaced apart from one another by one stitch length, i.e., the length of one feed step, the hook thread end is consequently longer than the needle thread end by the amount of the stitch length.
This situation and the result linked with it, which may have an adverse effect under certain circumstances, are shown in FIGS. 4 and 5 of the drawing in the case of a sewing machine with lower feed and in FIGS. 9 and 10 in the case of a sewing machine with combined lower feed and needle feed.
To avoid this situation, it is proposed in a thread-cutting device known from DE 16 85 087 B2 that the last stitch formation process, during which the thread cutting is to take place, be performed at the point at which the last complete sewing stitch was formed. Even though both the hook thread end and the needle thread end will thus hang down from the fabric at the same point and thus have the same length, this is achieved by accepting the drawback that a complete stitch must first be formed at this point after stopping the sewing machine and switching over the stitch length mechanism to zero stitch length before the half revolution of the arm shaft can take place as in the state of the art for performing the thread-cutting process. An additional stitch formation process must therefore be carried out in the prior-art thread-cutting device between the stopping of the machine and the thread cutting compared with the above-described state of the art. However, such an additional stitch formation process may lead overall to an undesired, considerable loss of time in the case of the sewing of a plurality of short seams.
SUMMARY AND OBJECTS OF THE INVENTION
The primary object of the present invention is therefore to provide a process for shortening the fabric-side hook thread end, during the performance of which no loss of time occurs.
According to the invention, a process is provided for shortening the fabric-side hook thread end in sewing machines with a thread-carrying needle, with a hook cooperating with the thread-carrying needle, with a take-up lever, with at least one feed element, and with a thread-cutting device with a catch thread device. The process includes stopping the sewing machine with the needle in a lower position and subsequently briefly driving the sewing machine once again until the take-up lever reaches its top dead center. The catch thread device is moved during this phase of movement of the sewing machine into its separating or catching position and the direction of feed of the feed element, of which there is at least one, is switched over into the reverse direction. The threads are cut at a point in time at which the take-up lever is located in its top dead center and the direction of feed of the feed element, of which there is at least one, has moved opposite the normal direction of feed by at least half of one feed step.
Based on the discovery that in a sewing machine with lower feed, the fabric feed dog will have covered more than half, namely, about 3/4 of its feed motion, in both forward and reverse feed, by the time at which the thread layer has reached its top dead center and at which the threads are cut, it is consequently achieved, due to the measure of reversing the feed motion into the reverse feed direction during a thread-cutting process, that the sewing stitch last formed is not removed farther from the stitch hole of the needle plate by about 3/4 stitch length as before, but it is moved closer to the stitch hole by about 3/4 stitch length. The consequence of this is that the fabric-side hook thread end is correspondingly shorter by twice the amount of the partial feed path, i.e., by about 11/2 stitch length, than in the prior-art process, while the fabric-side needle thread end essentially retains its already short length compared with the prior-art process.
A similar result is obtained in the case of sewing machines with combined lower feed and needle feed, in which the stitch hole is not contained in the needle plate but in the feed dog, which forms, together with the needle, the feed elements of the sewing machine which cooperate with one another. After the needle has emerged from the fabric and the feed dog has moved away from the fabric in the downward direction, the needle and the feed dog perform a horizontal movement directed against the normal feed motion by the amount of the stitch length before they again come into contact with the fabric. The stitch hole of the feed dog now moves away from the sewing stitch formed last by the same amount by which the sewing stitch moves away in sewing machines with lower feed from the stitch hole, which is stationary in such sewing machines. When the feed motion is switched over into the reverse feed direction during the performance of a thread-cutting process, the stitch hole moves toward the last sewing stitch to the extent that the fabric-side hook thread end will be shorter by far more than one stitch length than in the prior-art process in this case as well.
The process of shortening the previously longer hook thread end is preferably suitable for use in a sewing machine with a thread-cutting device which generates, like the thread-cutting device according to the later-published German Patent Application No. 197 22 395, especially short fabric-side thread ends. Optimally short thread ends are thus generated, which are required to avoid the subsequent cleaning of the thread, i.e., the subsequent cutting of projecting thread ends during the manufacture of cushions and during the manufacture of vehicle seats.
The present invention will be explained on the basis of two exemplary embodiments implemented in different sewing machines.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which preferred embodiments of the invention are illustrated.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a schematic representation of a sewing machine with lower feed;
FIG. 2 is a schematic representation of a sewing machine with combined lower feed and needle feed;
FIG. 3 is a schematic partially sectional side view of the position of the feed dog and catch thread device with the needle in the bottom dead center before the beginning of a thread-cutting process in a sewing machine with lower feed;
FIG. 4 is a schematic partially sectional side view of the position of the needle, feed dog and catch thread device after cutting the threads according to the prior-art process known from the state of the art;
FIG. 5 is a schematic view showing the cutting result for the prior-art process;
FIG. 6 is a schematic partially sectional side view of the position of the needle, feed dog and catch thread device after cutting the threads in the process according to the present invention;
FIG. 7 is a schematic view showing the cutting result for the process according to the present invention;
FIG. 8 is a schematic partially sectional side view of the position of the feed dog and catch thread device with the needle in the bottom dead center before the beginning of a thread-cutting process in a sewing machine with combined lower feed and needle feed;
FIG. 9 is a schematic partially sectional side view of the position of the needle, feed dog and catch thread device after cutting the threads in the prior-art process according to the state of the art;
FIG. 10 is a schematic view showing the cutting result in the prior-art process;
FIG. 11 is a schematic partially sectional side view of the position of the needle, feed dog and catch thread device after cutting the threads in the process according to the present invention, and
FIG. 12 is a schematic view showing the cutting result in the process according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The sewing machine with lower feed, which is schematically shown in FIG. 1, is of the usual design and correspondingly has a drive mechanism 2 connected to a drive motor 1 for the needle bar, not shown specifically, with the needle 3 and with the take-up lever 4. A horizontally rotating hook 7 shown schematically in FIGS. 3, 4 and 6 is arranged under a needle plate 5 with a stitch hole 6. The only feed element of the sewing machine is formed by a feed dog 8, whose rectangular movement is generated by a lifting drive 9 and a pushing drive 10. A stitch length mechanism 11 is associated with the pushing drive 10. The design embodiment of these mechanisms corresponds to those known from DE 31 50 141 C1, which corresponds to U.S. Pat. No. 4,491,080 (which is hereby incorporated by reference).
The sewing machine is equipped with a thread-cutting device 12, which has a catch thread device 13 with a cutting edge 14 (FIGS. 3, 4 and 6), and a knife 15. The drive mechanism of the thread-cutting device 12 is designated by 16. The design and the mode of action of the thread-cutting device 12 correspond to the thread-cutting device according to the above-mentioned German Patent Application No. 197 22 395. The knife 15 can be correspondingly moved from a resting position into a cutting position located adjacent to the stitch hole 6, which is a prerequisite for obtaining short fabric-side thread ends.
In conjunction with a pedal, not shown, a control device designated by 17 controls the drive motor 1, the course of the thread-cutting process over time and the time of the switchover of the stitch length mechanism 11.
FIG. 3 shows the initial situation before the beginning of a thread-cutting process, in which the sewing machine was stopped at the end of the seam with the needle 3 in the lower position. The catch thread device 13 and the knife 15 are in the resting position located away from the stitch hole 6 at this point in time.
As the thread-cutting process is initiated, the sewing machine is briefly driven once again. The hook 7 now performs a full revolution, the take-up lever 4 reaches the top dead center of its path of movement, and the feed dog 8 performs a partial feed step of about 3/4 of the stitch length.
The partial feed step takes place in the current feed direction V in the prior-art process, so that the sewing stitch St last formed is spaced from the stitch hole 6 by the amount L 1 =s+3/4 s, wherein s is the stitch length. At the time at which the hook 7 has widened the needle thread loop, the catch thread device 13 performs a catching or separating movement, by which the threads to be cut are caught. The knife 15 is moved at the same time from the resting position into the cutting position. FIG. 4 shows the situation immediately after the cutting through of the threads. The cutting points of the fabric-side ends NN1 and GN1 of the needle thread N and hook thread G, respectively, are located at a distance h 1 from the top side of the needle plate 5. Thus, a length of L GN1 =s+3/4 s+h 1 is obtained for the fabric-side hook thread end GN1 in the prior-art process. The fabric-side needle thread end NN1 has a length of L NN1 =3/4 s+h 1 . Thus, the fabric-side hook thread end GN1 is thus longer in the prior-art process than the fabric-side needle thread end NN1 by the amount of the stitch length s (FIG. 5).
In the new process, the stitch length mechanism 11 is switched over to reverse feed essentially simultaneously with the initiation of the movement of the catch thread device 13 at the beginning of the thread-cutting process. The consequence of this is that, according to FIG. 6, the partial feed step of the feed dog 8 now takes place in the reverse direction R, and the sewing stitch St formed last is correspondingly moved closer to the stitch hole 6 by the amount L 2 =s-3/4 s=1/4 s. Thus, a length of L GN2 =1/4 s+h 2 , in which h 2 is equal to h 1 , is obtained for the fabric-side hook thread end GN2 in the new process. The fabric-side needle thread end NN2 now has a length of L NN2 =3/4 s+h 2 , wherein L NN2 is equal to L NN1 . Thus, the fabric-side hook thread end GN2 is shorter in the new process by half the stitch length than the fabric-side needle thread end NN2 (FIG. 7).
The sewing machine with combined lower feed and needle feed, which is schematically shown in FIG. 2, is likewise of the usual design and correspondingly has a drive mechanism 21 connected to a drive motor 20 for the needle bar, not shown, with the needle 22 and with the take-up lever 23. A horizontally rotating hook 25, shown schematically in FIGS. 8, 9 and 11, is arranged under a needle plate 24.
This sewing machine has two feed elements, namely, a feed dog 26, which is arranged under the needle plate 24 and comes into contact with the fabric W through a corresponding opening 27 in the needle plate 24, on the one hand, and the needle 22, which synchronously cooperates with the feed dog 26, on the other hand. The rectangular movement of the feed dog 26 is generated by a lifting drive 28 and a pushing drive 29. A stitch length mechanism 30 is associated with the pushing drive 29. The feed motion to be performed by the needle 22 is generated by a pushing drive 31 acting on the pendularly mounted needle bar. A stitch length mechanism 32 is associated with the pushing drive 31. The two stitch length mechanisms 30 and 32 are mechanically connected to one another, so that the same stitch length is always set in both and the needle 22 always moves synchronously in the horizontal direction with the stitch hole 33 contained in the feed dog 26. The design embodiment of these mechanisms corresponds to that known from DE 33 24 715 C2, which corresponds to U.S. Pat. No. 4,528,923 (which is hereby incorporated by reference).
As in the first exemplary embodiment, the sewing machine is equipped with a thread-cutting device 34, which has a catch thread device 35 with a cutting edge 36 (FIGS. 8, 9 and 11), and a knife 37. The drive mechanism of the thread-cutting device 34 is designated by 38. The design and the mode of operation of the thread-cutting device 34 correspond to those known from the above-mentioned German Patent Application No. 197 22 395. In conjunction with a pedal, not shown, the control device designated by 39 controls the course of a thread-cutting process over time and the time of the switchover of the stitch length mechanisms 30 and 32.
FIG. 8 shows the initial situation before the beginning of a thread-cutting process, in which the sewing machine was stopped at the end of a seam with the needle 22 in the lower position. The catch thread device 35 and the knife 37 are in their resting position at this point in time.
As the thread-cutting process is initiated, the sewing machine is briefly driven once again, while the hook 25 performs a full revolution and the take-up lever 23 reaches the top dead center of its path of movement. In the prior-art process, the feed dog 26 and the needle 22 still continue to push the fabric W in the direction of feed V by a partial amount (FIG. 9) until the needle 22 exits from the fabric W and the feed dog 26 moves away from the fabric W in the downward direction at the same time.
The feed dog 26 and the needle 22 then perform a horizontal return movement in the reverse direction, which amounts to about 3/4 the set stitch length s. The stitch hole 33 of the feed dog 26 now moves away from the last sewing stitch St by the amount L 3 =s+3/4 s, pulling a corresponding amount of hook thread and needle thread after it. At the time at which the hook 25 has widened the needle thread loop, the catch thread device 35 performs a catching or separating movement, by which the threads to be cut are caught. The knife 37 is moved at the same time from the resting position into the cutting position.
FIG. 9 shows the situation immediately after the cutting of the threads. The cutting points of the fabric-side ends NN3 and GN3 of the needle thread N and hook thread G, respectively, are now located at a distance h 3 from the top side of the needle plate 24. A length of L GN3 =s+3/4 s+h 3 is thus obtained for the fabric-side hook thread end GN3 in the prior-art process. The fabric-side needle thread end NN2 has a length of L NN3 =3/4 s+h 3 . Thus, the hook thread end GN3 is also longer by the amount of the stitch length s than the fabric-side needle thread end NN3 in the prior-art process in the case of the sewing machine with combined needle feed and lower feed (FIG. 10).
With the needle 22 still inserted into the fabric W and with the feed dog 26 still in contact with the fabric W, the stitch length mechanisms 30, 32 are switched over to reverse feed in the new process in the course of the thread-cutting process by the end of a feed step that was performed in the forward direction V (FIG. 11). The consequence of this is that the needle 22 and the feed dog 26 are displaced jerkily in the reverse direction R by the amount of the stitch length s, and they pull the fabric W with them. As soon as the needle 22 has emerged from the fabric W and the feed dog 26 has moved away from the fabric W in the downward direction, the two feed elements 22, 26 perform the obligatory return movement, which now takes place, however, in the direction of feed V. This return movement also takes place in this case over a section of about 3/4 of the stitch length s set. As is apparent from FIG. 11, the stitch hole 33 of the feed dog 26 approaches the sewing stitch St formed last to a distance of L 4 =1/4 s. Thus, a length of L GN4 =1/4 s+h 4 is obtained for the fabric-side hook thread end GN4 in the case of the new process. The fabric-side needle thread end NN4 has the length L NN4 =3/4 s+h 4 .
Since the cutting point defined by the knife 37 located in the cutting position has a greater horizontal distance from the stitch hole 33 in the prior-art process according to FIG. 9 than in the new process according to FIG. 11, the amount h 4 is smaller than the amount h 3 . The fabric-side needle thread end NN4 is correspondingly shorter than the needle thread end NN3 obtained in the prior-art process. The fabric-side hook thread end GN4 is likewise shorter than the needle thread end NN4 by half the stitch length.
While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles. | The fabric-side hook thread end (GN), which was previously longer than the fabric-side needle thread end (NN) by the amount corresponding to a stitch length, is to be shortened in sewing machines with a thread-cutting device. This object is accomplished by the feed device of the sewing machine, of which there is at least one, performing a partial feed step in the reverse feed direction during the performance of the thread-cutting process. | 3 |
BACKGROUND OF THE INVENTION
The innovation pertains to a slice stacker, in particular for cheese slices and similar slice-shaped objects according to the governing principal of patent claim 1.
Slice-shaped objects of this type may be for example disks, card board strips, compact sausage slices or other food products which have a certain mechanical flexibility.
The innovation is based on the technical development described in GM 87 09 053.8.
The sample shows a slice stacker which consists of two parallel running brush belts with some distance between them, where the brush belts form a transport area.
From the feed side a cheese slice will be registered between the bristles of the brush belts which are located across from one another. There it comes to a halt at a designated vertical stop rail.
Registering a horizontal resting slice between the brushes, which are standing up and with belts located across from one another, has the disadvantage, that while exiting the shot belt and prior to the slice entering between the brushes, the slice has a certain ballistic trajectory which cannot be calculated exactly.
The trajectory depends on several parameters. For example the weight of the slice, the speed of the slice, the mechanical pliability of the slice and other parameters. Therefore it has not been achieved as of yet, to precisely designate the feed into the brush belt of such a slice.
The latest technical development has the disadvantage, that the slice cannot be fed precisely between the brushes of the brush belt and therefore it may tilt, slide off to its side, or may even fall out of the brush belt altogether.
SUMMARY OF THE INVENTION
The purpose of this innovation is however, to develop a slice stacker of the previously mentioned kind, which feeds a slice into the brush belt with much improved accuracy and the slice will be positioned at a defined position at the brush belt.
The solution of this task will be accomplished by the technical model of claim 1.
A significant feature of this innovation is the fact that the brush belt is positioned in a resting position and that the slices are being fed from the top or from the bottom, through the proper shot belt into the resting brush belt.
The significant advantage of this presented technical model is that due to the slices being fed vertically from at least one upper or lower shot belt, an accurate position between the bristles of the brush belts can be achieved.
Instead of an individual brush belt located on top and on the bottom, there may be several brush belts of this type arranged on the top and/or on the bottom.
Therefore, a ballistic trajectory is being avoided, since the slices in the horizontal position are not being fed in a way that they may bend or get deformed, ending up without definition. However, according to this innovation the slice is being fed between the bristle and the bristle belt in direction of gravity.
It is preferred that when the shot belt is located near the brush belt, that the slice is partially still supported by the shot belt and when leaving the shot belt it is already flowing over into the brushes of the brush belt where it is being defined.
The bristles of the brush belt will cause a breaking action to the fed slice and the slice then, will land on its lower seal edge at a working surface and will be supported through the seal seam in a spring-back fashion.
Tests have proven, that due to gravitational forces, the slice which is being fed through the bristles by the speed of the shot belt will then be slowed down and bounced back, and will then land with its lower seal seam on the working surface. Once there, it will jump upward, due to the elastic shaping of the seal seam, and will land on the working surface with its seal seam stretched.
This way, slices are being transported upright and are being fed into the brush belt with some distance between them and are being supported from both sides by the brushes.
When the bristles of the brush belt have a high density it is possible to pack the slices very close together on the brush band, because in principle, the brush belt has to only be moved by the width of an individual slice in the transport direction in order to immediately feed the next slice.
The advantage hereby is that the brush band can be packed very tightly with slices that need to be transported.
The result is a high packaging capacity in the area of the brush belt.
The shot belt for example travels at a speed of 2 meters per second, while the brush band travels at a speed of 0.10 meters per second.
Purpose of the aforementioned brush belt is that at first the individual slices are being fed through the individual bristles of the brush belt in order to create a stack as quickly as possible.
It is intended that in the outlet area of the brush belt--which is kept rather short--the stacking takes place.
During this process of stacking in the area of the brush belt and for the transport of the stack, a special protection is required, independent from the type and the arrangement of the brush belt.
It is essential that the stacking in the outlet area of the brush belt occurs when the slices are lined up in the bristles of the brush belt and when slices having some space between them, run up against a stop which is located within the transport area. This stop is not permanent, but is designed as a stop face in the area of the turnstile. This way the slices run in an upright position toward this vertically positioned stop face and back-up to a stack. A stack may consist for example of 10 to 25 slices. When the stacking process is completed the entire turnstile will turn for example by 90° and the upright stack will then be tilted and will reach the outlet area of an additional transport conveyor, from where the resting stack will be forwarded to an additional conveyor.
It is advantageous to install a stopping device with a sensor in the area of the brush belt, preferably in the form of a photo-electric cell or a light barrier, which prevent slices that are not part of a specific stack any longer, from still entering at the top of the stacking unit.
It is advantageous that the turnstile for example has four stop faces which have some space in between each other and the turnstile will then turn in four steps in order to assure a high stacking capability. This way, a very short processing distance from the upright stack to the resting stack is assured. The advantage is that due to this short processing distance the individual slices within each stack do not slide or fall out.
Of course, a turnstile change for various heights of stacks is provided/possible.
The entire unit has the advantage that it is built very compact and it takes up very little space, because as already mentioned, the brush belt is 350 mm long, while the stack-turn unit has a diameter of 135 mm.
Trademarks of the invented subject matter of the presented innovation do not only apply to the individual trademark, but also to other trademarks pertaining to this project.
All information and features disclosed in these documents, including the summary, and especially the dimensional development depicted in the drawings are considered essential to the invention as far as they are new individually or as a combination compared to the latest technical developments.
BRIEF DESCRIPTION OF THE DRAWINGS
The following drawings reflect only one particular type of innovation which is described closely. The drawings and their descriptions disclose additional features that are unique features and advantages of the new invention.
FIG. 1 is a schematic side view of the transport unit, according to the present invention;
FIG. 2 is a front view of the transport unit in the direction of arrow II in FIG. 1;
FIG. 3 is a top view of the transport unit in the direction of arrow III in FIG. 1;
FIG. 4 is a side view of the stacking unit; and
FIG. 5 is a top view of the stacking unit in the direction of arrow V in FIG. 4.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 schematically shows a shot belt 1 which essentially consists of two transport belts 2,3 which are working in opposite directions and which are driven in direction of arrows 4,5.
The transport belts 2,3 form a small transport gap 6, in which the slice 7 will be transported downward in direction of arrow 8.
Due to the high speed of the transport belts 2,3, the slice which is located in the transport gap 6 will be shot in the direction of arrow 8, in between the bristles of the transport unit which is positioned below.
The example shows that the transport unit 9, consists of deflection rollers 16,17, located on the left and on the right. A brush belt 23,24 in the form of a continuous belt runs and drives the deflection rollers 16,17.
An explanation of the construction of each brush belt 23,24 is only necessary once since the other brush belt and its drive is identical.
Each brush belt 23,24, consists as shown in FIG. 1 and 2 of an upper brush belt 10 and a lower brush belt 11.
Both brush belts are constructed of synthetic material to form a toothed belt. Stop blocks 14 are attached to the outer surface of each belt, as illustrated in FIG. 1 and the stop blocks form a mount for the bristles 13,15. The fasteners securing the stop blocks are not depicted in detail.
Each stop block 14 takes on a bristle packet 13 as well as 15 and the stop blocks 14 are arranged as a set, vertically one above the other, so that there are bristle packets 13,15 being formed, which are arranged in a set vertically above one another. To save costs, the brush belts 23,24 are divided into the upper and lower brush belts 10,11.
In other versions, the equipment may have a continuous brush belt versus the divided brush belts 23,24 (consisting of upper and lower brush belts 10,11).
The bristles 13,15 are preferably made of synthetic material.
The brush belts 23,24 are driven in direction of arrow 12, where the drive is activated by a driving axle 18, which is admitted by a drive and which is not described any further.
FIG. 1 shows that a rejection hatch 19 is located at position 19. This rejection hatch 19 is located at the bottom of a stop face 20, which is located across from the transport gap 6 of the shot belt, and which rotates at its rotational axis 26.
The rejection hatch 19 may be opened through a corresponding control when faulty material enters the transport unit 9 through the shot belt 1.
Otherwise, the slices 7 are being transported at high speed in direction of arrow 8, between the bristles 13,15 of the brush belts 23,24, and where they come to a stop. Here they hit against the bottom of the working surface 20 with their lower seal seam 22. They spring back slightly and align themselves between the bristles 13,15.
The upper seal seams 21 are projected above the upper brush belt 10.
It is not depicted in the continuation of the process (in direction of transport 12) that there are upper guide rails which make all slices 7 fully rest in an upright position and on their lower seal seams 22 on the working surface. It is also not depicted that there are vertical guide surfaces present on the side, which center the slices 7 approximately between the bristles 13,15, according to FIG. 2. These guide areas are indicated in the shape of the side guide 25 in FIG. 2.
In a further development of this innovation it may be possible to install a stopping device 31 in the area of the brush belt 23,24, which prevents that slices still reach the stacking unit that follows and which are not part of a specific stack 33.
FIG. 3 shows a sensor 48, located in the area of the stopping device 31, preferably a light barrier or photo-electric cell.
This stopping device 31 consists mainly of two pneumatic cylinders 27 which are positioned symmetrically across from one another. Each of these pneumatic cylinders 27 drives an adjoining piston rod 28. This piston rod 28 is connected with a stop rail 29 which consists of three different fingers 30. These fingers 30 are located parallel and with some distance from one another, where the lowest finger 30 is located below the lowest row of bristles of the lower brush belt 11, the middle finger 30 is located between brush belts 10 and 11 and the upper finger 30 is located above the upper brush belt 10 and presses itself on the side of the respective slice 7.
This is reflected in FIG. 3 where the fingers 30 press themselves against the side and where only the upper finger is visible.
In doing so, the fingers 30 are in a straight engagement position. This means they pile up the slices which have been transported by the brush belt in direction of arrow 12. This way no more than two to three slices arrive at the stop rails 29. They will then be forwarded in direction of arrow 12, after pulling back off the stop rails 29 from the transport area of the transport unit 9, until they reach position 32 in the area of the stacking unit 38.
The stacking unit 38 is described further in FIGS. 4 and 5.
It is now recognized that the slices 7 are running against the stop face 34 in direction of arrow 12 where they are being piled up.
It is hereby important, that several stop faces 34,35,36,37 are positioned evenly at the circumference of the turnstile and that the turnstile consists of individual fingers 45,46, which form the respective stop faces 34-37.
A stack of slices 33 for example is being formed at the stop face 34 which is defined by fingers 45,46.
Additional fingers 45a, 46a are positioned at a displaced angle of 90°, which defines stop face 37.
The entire turnstile may be driven step by step in its rotational axis 39. The drive 41 has sets of belts 42 which drive the turnstile through a corresponding deflection roller, in direction of arrow 40.
As shown in the example in FIG. 4, the slices 7 form a stack 33, by being piled up at the stop face 34. As soon as the stack has the required number of slices, the turnstile is turned by 90° in direction of arrow 40, so that the upright stack 33 can be moved to the resting stack 33a. This way, the resting stack of slices 33a is moved to a transport conveyor 43 and transported in direction of arrow 44.
It is important now, that when the upright stack 33 is transported by turning the turnstile in direction of arrow 40 to the resting stack, that there are no further slices being transported in direction of arrow 12 against the stacking unit 38. This is the purpose of the stopping device 31 as previously described. In this small space, the stopping device retains the transported slices 7 in the transport area of the transport unit, by engaging its stop rails 29.
As previously described, the turnstile consists mainly of fingers 45,46 or 45a, 46a, which are positioned at the perimeter and displaced by 90° from one another.
Of course the turnstile is not limited to this type of construction. For example, it may have only two stop faces positioned across from one another which are displaced in an angle of 180° from one another.
The fingers 45,45a or 46,46a as described are then being moved past the transport conveyor.
It is also possible to equip the conveyor 43 with individual transport belts and to guide the fingers 45, 46 between these belts and then through these belts around the outside of conveyor 43, as shown in our example.
The stack 33b which has been formed at conveyor 43 will then be moved to a packaging machine where the wrapping and sealing of the stack will take place.
Transport conveyor 47 is provided for this purpose.
Although a preferred embodiment of the invention has been described above by way of example only, it will be understood by those skilled in the field that modifications may be made to the disclosed embodiment without departing from the scope of the invention, which is defined by the appended claims. | This innovation describes a slice stacker, designed in particular for cheese slices and other slice-shaped objects, consisting of a brush belt with resting overhead or lower shot belts, which register slices from the top or from the bottom. | 1 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a method of changing the construction of a logical volume area in a storage and, more particularly, a method of expanding a logical volume area.
[0002] Conventionally, as a method of expanding the capacity in a storage, an expansion method by adding a physical disk is known. The method will be described with reference to FIG. 15 . Reference numeral 100 denotes a storage and 101 indicates a physical disk area as a collection of physical disks. In the physical disk area 101 , logical volumes called LU (Logical Units) designated by reference numerals 1011 x ( 1011 a, 1011 b, . . . ) are constructed. In the case of expanding the capacity of the storage, by adding a physical disk to the storage 100 , as shown by a broken line, an added disk area 102 is generated. When the logical volumes LU 1 ( 1011 a ) and LU 2 ( 1011 b ) in the physical disk area 101 become full, a new logical volume LU 3 ( 1011 c ) can be generated in the added disk area 102 .
[0003] However, in the case of expanding the area of an internal logical volume already allocated to increase the usable capacity of the storage, a problem occurs. For example, in the case of enlarging the LU 1 ( 1011 a ) in FIG. 15 , since the LU 2 ( 1011 b ) immediately follows, the LU 2 ( 1011 b ) has to be released. In order to enlarge the logical volume area in the storage 100 , the area has to be released once and allocation of the logical volume area has to be newly defined. Consequently, an access to a logical volume has to be interrupted.
SUMMARY OF THE INVENTION
[0004] As described above, it is easy to increase the capacity of a logical volume area by adding a physical disk even during operation of the system. On the other hand, since the logical volumes are constructed in an inner continuous area, the area of each logical volume cannot be expanded during operation of the system without newly adding a physical disk. In other words, to enlarge a logical volume area in a storage, the area has to be released once and a logical volume area has to be newly defined. A logical volume area cannot be therefore changed during operation of the system.
[0005] It is an object of the invention to enable the construction of a logical volume to be freely changed during operation of the system, for example, to expand a logical volume area in a storage. Specifically, an object of the invention is to provide a method of enabling the logical volume area to be expanded without releasing an existing logical volume area and expanding the logical volume area without interrupting an access to an existing logical volume.
[0006] A computer system to which the invention is applied, thereby obtaining effects has, for example, at least one computer, a storage, and a control utility for instructing a construction change in a logical volume in the storage.
[0007] According to the invention, the storage has logical volume control means for controlling the construction of the logical volume, and the logical volume control means is provided with a logical volume number map in which logical volume construction information is described. By describing the constructions of the computer and logical volumes and the combination with logical volumes in the storage which can be used by the computer, a construction change in the logical volumes can be freely made. By copying a plurality of separate logical volumes into a physically continuous area so as to be integrated to a single logical volume, management of the logical volume is facilitated.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a diagram showing the configuration of a computer system according to a first embodiment of the invention.
[0009] FIG. 2 is a diagram showing an example of an LUN map of a storage 1 in the first embodiment of the invention.
[0010] FIG. 3 shows a flowchart of a construction change in a logical volume LU in the first embodiment of the invention.
[0011] FIG. 4 is a diagram showing a state of the inner LUs in the physical disk area in the first embodiment of the invention.
[0012] FIG. 5 is a diagram showing an example of an LUN map before an inner LU is changed in the first embodiment of the invention.
[0013] FIGS. 6A to 6 C are diagrams showing examples of the LUN map after changing the inner LUs in the first embodiment of the invention.
[0014] FIG. 7 is a diagram showing a state of the inner LUs in the physical disk area of FIG. 6A .
[0015] FIG. 8 is a diagram showing the configuration of a computer system according to a second embodiment of the invention.
[0016] FIG. 9 shows a flowchart of a construction change in a logical volume LU in the second embodiment of the invention.
[0017] FIGS. 10A to 10 C are diagrams each showing the state of inner LUs in a physical disk area corresponding to a construction change of the logical volume LU according to the second embodiment of the invention.
[0018] FIG. 11 is a diagram showing an example of an LUN map before an internal LU in the second embodiment of the invention is changed.
[0019] FIG. 12 is a diagram showing an example of an LUN map after the internal LUs of the second embodiment of the invention are changed.
[0020] FIG. 13 shows a flowchart of a construction change in logical volumes LU of a third embodiment of the invention.
[0021] FIGS. 14A and 14B are diagrams each showing a state of an internal LU in a physical disk area corresponding to a construction change in the logical volume LU according to the third embodiment of the invention.
[0022] FIG. 15 is a diagram showing an example of the configuration of a storage according to a conventional technique.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0023] The invention will be described hereinbelow by referring to the drawings showing embodiments.
Embodiment I
[0024] FIG. 1 is a diagram showing the configuration of a computer system according to a first embodiment. Shown in the diagram are computers 2 x ( 2 a, 2 b, . . . , 2 n ), a storage 1 shared by all the computers 2 x, a management console 4 for managing the computer system, a fiber channel connecting device 3 for connecting all the computers 2 x, storage 1 , and management console 4 with each other, fiber channels 5 x ( 5 a, 5 b, . . . , 5 n ), a LAN (Local Area Network) 6 x ( 6 a, 6 b, . . . , 6 n ) used for communications between the plurality of computers 2 x and the management console 4 , and communication means 7 used for communications between the storage 1 and the management console 4 .
[0025] Each of the computers 2 x has therein logical volume management software 21 x ( 21 a, 21 b, . . . , 21 n ) called a file system FS or generally LVM, and a logical unit recognizing means 211 x ( 211 a, 211 b, . . . , 211 n ) for recognizing a logical volume construction or the like of the storage 1 and notifying the logical volume management software 21 x of a change in the construction. The logical volume is a virtual volume provided in the storage 1 and is a name defined in the specification of an SCSI (Small Computer System Interface) as one of protocols of an interface connecting the computer 2 x and the storage 1 . In the following, the logical volume may be also simply called an LU (Logical Unit). A number for identifying an LU will be called a logical unit number (LUN).
[0026] The management console 4 has a control utility 41 used to display the LU construction in the storage 1 , set an LU in the storage 1 by the manager of the system, and so on. The control utility 41 is disposed on the management console 4 in this case but may be disposed in the computer 2 x or storage 1 .
[0027] The storage 1 has therein a logical volume control means 11 for controlling the construction of a logical volume in the storage 1 and notifying of logical volume construction information in response to a request from the logical volume recognizing means 211 x in each computer 2 x. Reference numeral 111 denotes a logical volume number map (LUN map) and is, as a component of the LU control means 11 , a map showing logical correspondence between the logical volume in the storage 1 and the logical volume recognized by the computer 2 x. Reference numeral 12 denotes a physical disk area which is a collection of physical disks. In the physical disk area 12 , logical volumes 121 x ( 121 a, 121 b, . . . , 121 n ) logically generated are provided.
[0028] The logical volume LU will be described. The LU is a logical volume seen from a computer 2 x ( 2 a, 2 b, . . . , 2 n ) of the storage 1 . The computer recognizes an LU as a logical disk drive. The storage 1 defines and internally constructs a plurality of LUs which will be called internal logical volumes (internal LUs). In the storage 1 , in order to control the internal LUs, integers starting from zero are serially given to the internal LUs. The numbers will be called internal logical volume numbers (internal LUNs).
[0029] Generally, a computer searches a storage connected for an LU at the time of booting the OS. There are the following two constraints to searching methods, which are techniques of shortening a search time.
[0030] (a) To search the logical volume numbers LUN sequentially from 0.
[0031] (b) To stop searching when a certain number does not exist on assumption that the logical volume numbers LUN exist as serial numbers.
[0032] It is also assumed that the computer of the invention has such characteristics. In such a case, when the internal logical volume number LUN is assigned as it is to a computer, a computer to which a number other than zero is assigned cannot detect the LU. Specifically, in each of all the computers, it is assumed that the logical volume numbers LUN used by the computer start from zero. When the inner logical volume numbers are directly assigned as the logical volume numbers LUN, consequently, for the computers to which numbers other than zero are assigned as the internal LUNs, it is equivalent that no logical volume LU is assigned. Therefore, the inner logical volume numbers LUN starting from zero seen from the computer and which are serial numbers have to be assigned to each of all the computers.
[0033] In the invention, the storage 1 re-defines the internal LUs used by a computer 2 x so that serial logical volume numbers starting from 0 when seen from the computer 2 x are assigned to the internal LUs used by the computer 2 x, thereby solving the problem. An LU recognized by each computer 2 x will be called an outer logical volume (outer LU) and the number assigned to the outer LU will be called an outer logical volume number (outer LUN), so as to be distinguished from the inner LU and inner LUN, respectively. According to the invention, LUN combining information to define the relation between an outer LU and an inner LU is provided between the outer and inner LUs. By using the LUN combining information, the construction of combination between the outer and inner LUs can be changed. The corresponding relations among the outer LUN,.LUN combining information, and inner LUN are managed by the LUN map 111 in the storage 1 .
[0034] FIG. 2 shows an example of the LUN map 111 of the storage 1 . In the LUN map 111 , port number, target ID, outer LUN, LUN combining information, inner LUN, WWN, S_ID, and property are stored. The items will be described hereinbelow.
[0035] In the “port number”, the number of a fiber channel connection port of the storage 1 is stored. In the embodiment, the number of port is assumed to be one, and “0” is stored.
[0036] The “target ID” is an identification of the storage 1 in the connection interface between the computer 2 x and the storage 1 . As in the embodiment, when the connection interface between the computer 2 x and the storage 1 is a fiber channel, the only one D_ID (Destination ID) is assigned to each port. Since there is the item of the port number, the target ID may be omitted or D_ID determined at the time of initializing a fiber channel connection port may be stored. In the case of the SCSI, the same port can have a plurality of IDs, so that the target ID to which each LUN belongs is stored. In the embodiment, it is assumed that the fiber channel is used, so that the column of the target ID is not used and zero is stored.
[0037] The outer LUN, LUN combining information, and inner LUN show corresponding relations of each LUN. First, areas of physical disks in the storage 1 are the logical volume areas having inner LUNs 0 to n−1 and the logical volume areas having the inner LUN k. To each of the former areas, “0” is assigned as the outer LUN. To each of the latter areas, “1” is assigned as the outer LUN. The LUN combining information is information indicative of combining relation between the outer and inner LUNs. The left side of the LUN combining information indicates the total number of inner LUs assigned to the outer LU and the right side of the LUN combining information indicates the order of the inner LUs. Both of the numbers are connected via a hyphen.
[0038] The “top LBA” indicates an address in the outer LU to which the top address in each inner LU is assigned when it is seen from the computer 2 x. LBA (Logical Block Address) denotes an address in an LU, and the computer 2 x accesses data in the LU by using the address. When an outer LU is constructed by a single inner LU, “0” is assigned to the top LBA. In the case where an outer LU is constructed by a plurality of inner LUs due to a change in the construction of the LU, the top LBA is rewritten. This point will be concretely described when an example of the construction change of an LU will be described later.
[0039] “The number of blocks” indicates the number of logical blocks in each inner LU, and the size of each inner LU can be known by the number of blocks.
[0040] In the “WWN”, world wide name as information to specify each computer 2 x is stored. In a port-login process to establish a connection between a connection port of a fiber channel and a port, the WWN of each computer 2 x is notified to the storage 1 .
[0041] “S_ID” denotes ID information stored in a frame header of a fiber channel and is an ID of a source (initiator) which generates a frame. S_ID is dynamically assigned at the time of initializing a fiber channel. The above-mentioned WWN is a value unconditionally set according to the connection port of each fiber channel exchanged at the time of initialization. When WWN and S_ID are associated with each other, without checking the WWN each frame, only by checking S_ID, the computer 2 x can be specified.
[0042] The “property” indicates the property of each LU. “Exclusive” denotes an LU exclusively used by a single computer 2 x. “Common” indicates an LU shared by a plurality of computers 2 x.
[0043] It is understood from the LUN map 111 shown in FIG. 2 that the inner LUs having the LUNs 0 to n−1 are exclusively assigned to the computers 2 a to 2 n, respectively. Although the inner LUNs are serial numbers, all the outer LUNs are “0”. It is further known that an area having the inner LUN k is set for the common LUs. To the inner LU, the outer LUN of 1 is set. In the case of searching a storage at the time of booting the OS, by searching for 0 of the outer LUN and then 1, each computer can know inner LUs which can be used by itself.
[0044] A construction change in the logical volume LU will now be described by referring to the flowchart of FIG. 3 .
[0045] The operator of the management console 4 sends an indication for LU construction change from the control utility 41 . In the case of expanding an LU, the inner LUN of the LU to be expanded and an inner LUN of an LU newly coupled are designated. The indication is sent via the communication means 7 to the storage 1 (step 701 ).
[0046] The LU control means 11 in the storage 1 receives the indication and determines whether the designated LU is correct or not (step 702 ). When the designated inner LU is not correct such that a not-existing LUN is designated, the inner LU to be newly combined has already assigned to another computer 2 x; or the like, the LU control means 11 returns an error signal to the control utility 41 and the routine is finished (step 708 ). When the designated LU is correct, the LU control means 11 rewrites the LUN map 111 in accordance with the indication (step 703 ).
[0047] The LU construction change is notified to the LU-recognizing means 211 x in the computer 2 x by arbitrary one of the following methods; a method of transmitting the message from the LU control means 11 to the LU recognizing means 211 x via the fiber channel 5 x, a method of notifying the control utility 41 of the message by the LU control means 11 in the storage 1 and notifying the message from the control utility 41 to the LU recognizing means 211 x in the computer 2 x via the LAN 6 x, and a method of operating the computer 2 x directly by the manager to notify the LU recognizing means 211 x of the message (step 704 ).
[0048] The LU recognizing means 211 x gets the changed LU size from the LU control means 11 . The LU recognizing means 211 x may request the LU control means 11 to present the construction information without receiving the notification of the construction change. In this case, the notification of the construction change (step 704 ) can be omitted (step 705 ).
[0049] The LU recognizing means 211 x notifies the information of the changed LUN and the size to the logical volume management software 21 x (FS or LVM) and the changed LU is enabled to be used on the computer 2 x (step 706 ).
[0050] As described above, while continuing an on-line access to an existing LU, the construction change can be made reflected.
[0051] An example of the LU construction change will now be concretely presented and rewriting of the LUN map 111 will be described in detail. As an example of the LU construction change, a case of expanding the LU 0 area in the computer 2 a will be taken. FIG. 4 shows a state of the inner LUs in the physical disk area 12 . 120 x ( 120 a to 120 c ) denote inner LUs. In the physical disk area 12 , an LU 0 area 120 a, an LU 1 area 120 b, and an LU 2 area 120 c are continuously constructed. To simplify the explanation, it is now assumed that the LU 0 area 120 a is assigned to the computer 2 a, the LU 1 area 120 b is assigned to the computer 2 b, and the LU 2 area 120 c is of an inner LU which is not assigned to any computer. In the example, although the LU area 120 c is of the inner LU which is not assigned to any computer, since the LU 1 area 120 b is formed continuously after the LU 0 area 120 a, the LU 0 area 120 a cannot be expanded physically. In this state, the computer 2 a sees the LU 0 area 120 a as its logical volume, and the computer 2 b sees the LU 1 area 120 b as its logical volume.
[0052] FIG. 5 shows the LUN map 111 at this time. The inner LUN 0 area is assigned to the computer 2 a (WWNa), the inner LUN 1 area is assigned to the computer 2 b (WWNb), and the inner LUN 2 area is blank (and the items are not defined). When a request of expanding the LU of the computer 2 a is received, as described by referring to FIG. 3 , the LU control means 11 rewrites the LUN map 111 so that the inner LU 2 120 c becomes the inner LU of the computer 2 a on the basis of the instruction of the construction change sent from the control utility 41 . FIG. 6A shows the LUN map 111 rewritten in such a manner. As understood from the above, the computer 2 a can recognize LUs having the inner LUNs 0 and 2 as the LUs which can be used by itself. Since the inner LUN 2 is used continuously after the inner LUN 0 , it is assumed that a process starts from the number of blocks of the top LBA of the inner LUN 2 . The process is performed by the LU control means 11 . In association with the process, WWN, S_ID, and the like corresponding to those of the computer 2 a are stored. In the case of accessing the LU from the computer 2 a, either the inner LU 0 or LU 2 to be accessed can be known from the top LBA.
[0053] FIG. 7 is a diagram for explaining the state of the inner LUs in the physical disk area 12 rewritten as described above. As obviously understood in contrast to FIG. 4 , although the inner LU 120 x ( 120 a to 120 c ) are formed continuously in a manner similar to the above, an area 122 indicated by an alternate long and short dash line functions as an LU of the computer 2 a. In this state, the computer 2 a sees the total area 122 of the LU 0 area 120 a and the LU 2 area 120 c as a logical volume which can be used by itself. The computer 2 b sees the LU 1 area 120 b as its logical volume.
[0054] FIGS. 6B and 6C show LUN maps 111 of other examples of the changed LU construction. FIG. 6B shows a state where, in addition to the logical volume obtained by adding the inner LU 2 to the inner LU 0 for the computer 2 a, the inner LU 5 is further added. FIG. 6C shows a state where, in addition to the logical volume obtained by adding the inner LU 5 to the inner LU 0 of the computer 2 a, the inner LU 2 is further added. That is, FIGS. 6B and 6C show examples which are different from each other with respect to the order of adding the inner LUNs. The difference in the orders does not mean anything for the computer 2 a. As long as the LU control means 11 properly stores the top LBA and information such as WWN, S_ID, and the like associated with the construction change, in any of FIGS. 6B and 6C , the construction of the logical volume having the block numbers of the total three inner LUs can be used to execute the function of the computer of the LU control means 11 .
[0055] By virtually managing the LU areas as described above, the construction change such as expansion of an LU which cannot be physically made out can be realized.
[0056] According to the embodiment, an effect of freely changing the construction of the logical volume areas in the storage is produced. According to the embodiment, another effect such that the logical volume area can be expanded while continuing an access to an existing logical volume is produced. Further, according to the embodiment, the construction can be changed in the storage, an effect such that the logical volume area can be expanded independent of the OS of the computer is produced.
Embodiment II
[0057] FIG. 8 is a diagram showing the configuration of a computer system according to a second embodiment. The construction of the computer system is the same as that of the first embodiment except for the point that a copy means 13 is added to the storage 1 . The copy means 13 is a means for copying an LU to another area.
[0058] An LU construction change will be described by using the flowchart of FIG. 9 . The operator of the management console 4 sends an indication for LU construction change from the control utility 41 . In the case of expanding an LU, the inner LUN of the LU to be expanded and an expansion size are designated. This indication is sent to the storage 1 via the communication means 7 (step 801 ).
[0059] The LU control means 11 in the storage 1 receives the indication and determines whether the total size of the size of the designated inner LU and the expansion size can be assured from the free area or not (step 802 ).
[0060] When the area cannot be assured, the LU control means 11 sends an error signal to the control utility 41 , and the routine is finished (step 809 ).
[0061] When the area can be assured, the LU control means 11 assures the area and sends a copy instruction for copy to the copy means 13 (step 803 ). The copy means 13 which has received the copy instruction copies the designated LU. After finishing the copying of the LU, the copy means 13 notifies a finish of copy to the LU control means 11 (step 804 ).
[0062] When the notification of copy end is received, the LU control means 11 rewrites the LUN map 111 and assigns a newly generated LU to the computer 2 x (step 805 ).
[0063] The processes in step 806 and subsequent steps are similar to those in the first embodiment.
[0064] An LU construction change will now be concretely described. FIG. 10 is a diagram for explaining an example of the construction change of the embodiment. FIG. 10A shows a state of the inner LUs before a change. In a manner similar to the case of FIG. 4 , a case of expanding the LU 0 area of the computer 2 a will be taken as an example. In the physical disk area 12 , the LU 0 area 120 a and LU 1 area 120 b are continuously constructed, the LU 0 area 120 a is assigned to the computer 2 a, and the LU 1 area 120 b is assigned to the computer 2 b. In this example, it is assumed that the area other than those areas is a free area. In this example as well, although there is a sufficient free area, the LU 1 area 120 b is formed continuously after the LU 0 area 120 a, so that the LU 0 area 120 a cannot be physically expanded. In a manner similar to the first embodiment, the computer 2 a sees the LU 0 area 120 a as its logical volume, and the computer 2 b sees the LU 1 area 120 b as its logical volume.
[0065] A copying operation related to expansion of an LU will be described first. When the operator of the management console 4 sends an indication for an LU construction change in which an inner LUN of the LU to be expanded and the expansion size are designated via the control utility 41 to the LU control means 11 , the LU control means 11 assures an area of a new LU 2 in a total size of the area size of the inner LUN of the LU to be expanded and the expansion area size in the free area 123 . When the area cannot be assured, an error signal is sent to the control utility 41 . The LU control means 11 instructs the copy means 13 to copy the data of the LU 0 120 a to the assured area LU 2 120 d from the top position of the area LU 2 120 d. FIG. 10B is a diagram for explaining a copying state by the copy means 13 . As shown by a broken line in the area LU 2 120 d, the data is copied from the LU 0 120 a to the LU 2 120 d. After copying all the data of the LU 0 120 a to the LU 2 120 d, the copy means 13 notifies an end of the copy to the LU control means 11 . FIG. 10C shows a state of the inner LUs after completion of the copying. The LU control means 11 which has received the copy end notification rewrites the LUN map 111 and assigns the LU 2 120 d to the computer 2 a. The LU 0 120 a is not defined.
[0066] FIG. 11 shows an LUN map before updating, and FIG. 12 shows an updated LUN map. It is understood that, in the LUN map before updating, the computer 2 a is assigned to the inner LUN 0 . The computer 2 a is assigned to the inner LUN 2 in the updated LUN map. Moreover, the number of blocks of the inner LUN 2 is larger than the initial number of blocks. It is therefore understood that the area enlargement has been realized by using a new area. By using the copy means as described above, a new inner LU is generated while holding the original data in the LU, so that the construction change such as LU expansion can be realized.
[0067] There is a case of accessing an LU from a computer during copying operation for the LU area change. In this case, when an access is a read access, it is sufficient to read data from the original LU area. If it is the write access, however, there is the possibility that a data discrepancy occurs unless data is written in both the original LU area of the corresponding address and a new LU area. When the target of the write access is the original LU area on which the copying operation has not been completed by the copy means 13 , there is no problem. When the target of the write access is the original LU area on which the copying operation has already been finished, even if data of the address is updated, the new data is not read and copied to the new LU area. Consequently, if the copy end is notified in step 804 , a data discrepancy occurs. When there is the possibility of occurrence of such a data discrepancy, the LU control means 11 writes data to areas of both the addresses during a period from step 802 to step 805 . It is also possible to notify the address of the new area to the computer, and write the data to areas of both addresses by the computer.
[0068] As described above, by copying the data of the existing LU into a newly assured area, while utilizing the existing data, an LU area expansion or the like can be performed. Since one inner LU is assigned to one outer LU, the management is facilitated. According to the embodiment, the same effects as those of the first embodiment are obtained. Moreover, since the logical volume area is assigned to the physically continuously area, an effect such that the management of the logical volume is facilitated is produced.
Embodiment III
[0069] A third embodiment will be described. A computer system of the third embodiment is the same as that in the second embodiment. The third embodiment is realized by a combination of virtual combining of logical volumes in the first embodiment and expansion by the copying means in the second embodiment.
[0070] The LU construction change will be described by referring to the flowchart of FIG. 13 .
[0071] The operator of the management console 4 sends an indication for LU construction change from the control utility 41 . In the case of expanding the LU, all the inner LUNs assigned to the outer LU to be expanded and an expansion size are designated. The instruction is sent via the communication means 7 to the storage 1 (step 901 ).
[0072] The LU control means 11 in the storage 1 receives the instruction and determines whether the total size of the size of all-the designated inner LUs and the expansion size can be assured in the free area or not (step 902 ).
[0073] If the area can be assured, all the designated LUs are copied by copy means and a new inner LU is generated. At this stage as well, a measure to avoid a data discrepancy described in the second embodiment is taken. The subsequent process is similar to that in the second embodiment (step 903 ).
[0074] When the area of the total size cannot be assured in the free area, the LU control means 11 determines whether virtual combination is possible or not. When the area of the expansion size can be assured, the virtual combination can be performed (step 904 )
[0075] When the virtual combination can be performed, the assured area of the expansion size is virtually combined with the LU to be expanded (step 905 ). The following process is similar to that of the first embodiment.
[0076] If the virtual combination is impossible, the LU control means 11 returns an error signal to the control utility 41 and the routine is finished (step 906 ).
[0077] An example of the result of the LU construction change according to the third embodiment will be described with reference to FIGS. 14A and 14B . Reference numeral 12 denotes a physical disk area, and reference numerals 121 x ( 121 e to 121 h ) indicate inner LUs. FIG. 14A shows a state where the logical volumes are virtually combined according to the first embodiment, thereby constructing the outer LU 122 . In this state, the computer sees the outer LU 122 as a single LU. In the storage, however, it is known that the inner LU 0 121 e and the inner LU 2 121 g are separated from each other. FIG. 14B shows a state where a new inner LU 3 121 h having an area to be enlarged like the second embodiment is constructed. The data in the inner LU 0 121 e and the inner LU 2 121 g which are separated from each other is copied in a physically continuous area and combined as a signal inner LU. In any of the cases, the LUN map 111 is updated in correspondence with the case.
[0078] As described above, by combining the virtual combination of logical volumes in the first embodiment and expansion by the copy means in the second embodiment, a more flexible logical volume construction change can be realized. Particularly, since a plurality of separated LUs can be collected in a physically continuous area and integrated to a single LU, the management of the inner LUs can be facilitated.
[0079] As understood also from the description of the embodiments, the logical volume number map 111 of the invention does not have to have all the port number, target ID, outer LUN, LUN combining information, inner LUN, top LBA, the number of blocks, WWN, S_ID, and property as in the embodiments. For example, as understood from FIG. 6 , since the top LBA can be calculated as a cumulative total of the numbers of blocks of inner LUs including the immediately preceding LU, it is sufficient to calculate the top LBA as necessary. In short, it is sufficient that the combination of the outer LUN seen from the computer and the inner LUN of the storage is clearly defined, and the computer to which the combination is used is known. | In order to enable an area of each logical volume to be expanded while continuously using the logical volume and to integrate separate logical volumes in a single continuous area, a storage has logical volume control means for controlling the construction of a logical volume, a logical volume number map in which logical volume construction information is described, and copy means for copying the logical volume. By allowing two or more inner logical numbers to be described per external logical number in the logical volume number map, improved flexibility in combining the logical volumes in the storage is achieved. By copying a plurality of separate logical volumes into a physical continuous area by the copy means, the logical volumes are integrated. | 6 |
PRIORITY INFORMATION
This application is related to, and claims priority from, U.S. Provisional Patent Application No. 60/231,256 filed Sep. 8, 2000, the entire contents of which are incorporated by reference herein.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to air fresheners and supply units therefore.
2. Description of the Related Art and Summary of Invention
Air fresheners are frequently used in home and business to control odors in bathrooms, kitchens, and other enclosed spaces. Generally, commercial dispensers for air fresheners can operate passively through ventilation and diffusion, or actively through electrical heating elements or mechanical fan assemblies. Because air freshener dispensers function by releasing a scent through evaporation or atomization, such dispensers work most effectively when placed in the open on a counter, table, or wall. They are nevertheless often hidden from view due to their odor eliminating purpose, where they are both less effective and more difficult to replace.
Numerous methods have been developed to improve air freshener dispensers for the home and business. Electrically powered and wall mounted dispensers are common. U.S. Pat. No. 4,808,347 to Dawn discloses an air freshener with a battery powered fan for deodorization of automobiles. Similarly, U.S. Pat. No. 4,743,406 to Steiner et al. describes a self-contained dispenser which uses replaceable cartridges of air freshener, and applies a battery powered fan to actively vent air past the cartridge. Air freshener dispensers have even been applied to common cassette tapes, as disclosed in U.S. Pat. No. 4,905,112 to Rhodes, in part to deodorize automobiles in a discrete and clever fashion. Unfortunately, none of these solutions provide an ideal solution for the home, office or storefront, as many require electric power, often necessarily with replacement of batteries as well as air freshener. These solutions usually do not suit themselves to placement in visible areas where such air freshener dispensers would be most effective.
Hand lotion, on the other hand, is commonly provided in home and business environments to moisturize, smooth, and improve the condition of skin. It is often available in disposable consumer pour or pump dispensers, or sometimes in wall units for commercial application. Consumer dispensers are commonly placed on tables, in kitchens, and in bathrooms, and do not have the less desirable appearance and connotation of an air freshener dispenser.
Applicant is one of the named inventors for U.S. Pat. No. 5,799,826, in which a dual dispenser was disclosed. That dual dispenser was disclosed as being used with soap and air freshener. This combination of soap and air freshener in a single dispenser was highly innovative for soap. When used with standard soap (which is rinsed off), rather than a sanitizer soap (which is not rinsed off), the dispenser is desirably placed reasonably near a source of water to allow washing off the soap after use. As standard soaps are by far the most popular, the placement of standard soap dispenser is limited, as it is impractical in non-washroom settings such as the coffee table, office desk, or the automobile.
Accordingly, a preferred embodiment is a dispenser that can be placed virtually anywhere in the home or office. Another aspect of a preferred embodiment is a dispenser for both air freshener and a liquid, such as hand lotion or soap, that avoids the difficulties of prior individual and combined dispensers while providing advantageous improvements in both structure and function.
Most retail, or consumer-oriented, air fresheners operate on an “always on” basis. That is, once the air freshener is initially activated, it dispenses fragrance until its supply is exhausted. Because air freshening is typically only necessary when a person is in the same general area as the air freshener dispenser, the “always on” dispensers may result in a majority of the fragrance being dispensed when it is not necessary or desired.
Further, the dispensed fragrance, along with most other odors, are only noticeable to a person for a short time after the smell is encountered. After this initial period, the person becomes accustomed to the fragrance and it no longer produces the desired sensory response. More user oriented consumer air fresheners are available, such as spray-type products, for example. However, the necessary mechanisms to propel the air freshener often make spray-type dispensers relatively expensive and difficult to recycle.
Accordingly, a preferred dispenser dispenses only a small amount of fragrance, if any, until the dispenser is user-actuated. Advantageously, such an arrangement avoids desensitization, thus increasing the perceived effectiveness of the air freshener. In addition, such a dispenser avoids unnecessary dispensing of fragrance, thereby increasing the useful life of the fragrance. Moreover, such a dispenser provides both a pourable compound, such as hand lotion, and air freshener in a single product, which is less costly than purchasing hand lotion and air freshener separately. In addition, less packaging materials are utilized in comparison to separate products, thereby reducing the amount of material disposed of or needing to be recycled at the end of the product life.
A preferred embodiment is an assembly including a dispenser. The dispenser includes a container and an actuator, which defines an actuation surface. A pourable compound is held within the container and is dispensible from the container upon manual manipulation of the actuation surface. A base defines a substantially flat mounting surface and an interior surface sized and shaped to receive and retain the dispenser. The base also includes a location sized and shaped to receive a supply of air freshener wherein the supply of air freshener is received by the location.
A preferred embodiment is an air freshener delivery assembly. The assembly includes a bottle, a hood and a supply of air freshener. The hood includes a wall cooperating with at least a portion of the bottle to form a cavity. The supply of air freshener is positioned within the hood. In addition the hood is movable with respect to the bottle from a first position, wherein the hood and the bottle cooperate to define a first generally enclosed volume, to a second position wherein the hood defines a second enclosed volume smaller than the first enclosed volume, thereby dispensing air freshener from the supply of air freshener.
A preferred embodiment is an assembly including a first engagement portion defining a cavity and an actuator defining an actuation surface. A pourable compound is positioned within the first engagement portion, wherein the compound is dispensible from the first engagement portion upon manual manipulation of the actuation surface. The assembly also includes a second engagement portion, which defines an interior surface sized and shaped to receive and retain the first engagement portion. The second engagement portion also defines a location sized and shaped to receive a supply of air freshener, which is positioned at the location.
A preferred embodiment is an assembly including a first engagement portion defining a cavity and an actuator defining an actuation surface. A supply of hand lotion is placed within the first engagement portion, wherein the supply of hand lotion is dispensible from the first engagement portion upon manual manipulation of the actuation surface. A second engagement portion defines a location sized and shaped to receive a supply of air freshener and a supply of air freshener is positioned at the location.
A preferred embodiment is a dispenser assembly including a first portion at least partially defining a first enclosure for receiving a supply of hand lotion. A second portion at least partially defines a second enclosure for receiving a supply of air freshener. The second portion has at least one opening and is movable relative to the first portion to a dispensing position for urging the air freshener in a direction from within the second enclosure toward the opening. A pump assembly communicates with the supply of hand lotion and defines an outlet positioned outside of both the first and second enclosures. The hand lotion is urged in a direction from within the first enclosure toward the outlet when the pump assembly is actuated. The second portion is movable to the dispensing position independent of the actuation of the pump assembly.
A preferred embodiment is a dispenser assembly including a first portion at least partially defining a first enclosure for receiving a supply of hand lotion. A second portion at least partially defines a second enclosure for receiving a supply of air freshener. The second portion has at least one opening. A pump assembly communicates with the supply of hand lotion and defines an outlet positioned outside of both the first and second enclosures. The hand lotion is urged in a direction from within the first enclosure toward the outlet when the pump assembly is actuated. A means is provided for dispensing the air freshener from within the second enclosure through the opening without an external supply of power.
A preferred embodiment is a dispensing base for use with a liquid dispenser and an air freshener enclosure. The base includes a substantially flat mounting surface and an interior surface sized and shaped to receive the liquid dispenser. The base also includes a location sized and shaped to receive the air freshener enclosure. The base defines at least one hole through which air freshener from the air freshener enclosure can be dispersed.
Another aspect of a preferred embodiment is a combination air freshener and hand lotion dispenser that permits direct user control of the strength and quantity of scent released in relation to dispensing of hand lotion.
Yet another aspect of a preferred embodiment is a combination air freshener and hand lotion dispenser in which the supplies of hand lotion and/or air freshener are refillable or replaceable independently or as a unit.
Still another aspect of a preferred embodiment is a combination air freshener and hand lotion dispenser where the dispensing of hand lotion, for example through a pump, is used to indirectly power the release of air freshener through a mechanically powered or passive ventilation system.
Finally, yet still another aspect of a preferred embodiment is a combination air freshener and hand lotion dispenser where the release of air freshener and dispensing of hand lotion are independently controllable.
Hand lotion is often dispensed in pour, squeeze, or pump bottles for home and business environments, where those bottles are usually disposable. As is known by those of skill in the art, hand lotion may include various combinations of moisturizers, oils and emollients, and may include nutritive elements such as Vitamin A, Vitamin E or Aloe Vera. While hand lotion may be scented, its primary function is placement directly on the hands to improve the skin's condition. Hand lotion generally does not have to be washed off the hands after use, as with standard soap. It does not function efficiently as an air freshener, and would be ineffective and messy if used as such. Hand lotion is an emulsion of primarily water and various oils, with lecithin typically being at least one of the emulsifying agents. If skin renewal properties are desired, the lotion may contain 2-8% of an alpha or beta hydroxy ingredient, to promote exfoliation.
Air freshener means any entity designed for the purpose of masking odors, or freshening, cleaning or deodorizing the air. The main ingredient of most air fresheners is a fragrance. Air fresheners previously had a chemical composition consisting of 10-25% fragrance, although substantially more or less fragrance, between 1-99% would be present depending on the strength of the resulting scent, the placement and purpose of the air freshener and the type of carrier the fragrance is placed within. Carriers for fragrance may include, for example, an odorless mineral spirit to dilute and aid in evaporating the fragrance, polymer gel, or a semisolid wax, which evaporates the fragrance at ambient temperature or upon heating. A porous surface frequently is used to prevent leakage but allow diffusion of fragrance into the surrounding environment, including, for example a polyester matrix in which the fragrance and carrier can be suspended. In 1997, the EPA established Volatile Organic Compound (VOC) content limits for air fresheners. Since fragrances very often contain VOC, these limits must be considered in the process of air freshener design. However, VOC content limits do not apply to air fresheners whose VOC constituents consist of 100% fragrance. This latter kind of air freshener can contain any desired amount of fragrance (0-100%).
Preferred embodiments realize an advantageous combination air freshener dispenser and hand lotion dispenser. A preferred embodiment includes a method for combining a hand lotion dispenser and air freshener dispenser to allow control of air freshener diffusion based on dispensing of hand lotion, or, alternatively, passively diffusing air freshener through controlled continuous ventilation. Both methods may be combined in the same apparatus. This can be accomplished through a number of physical embodiments, the preferred of which are described below.
A preferred embodiment includes an apparatus for combining a hand lotion dispenser and air freshener dispenser to allow subtle continuous dispensing of air freshener passively through the use of one or more adjustable vents. Thus, within one embodiment of a dispenser, at least two vent units are included where one of the vents is moveable with respect to the other. The vent units may have one or more openings in each which allow communication of fragrance from the air freshener enclosure to the outside environment. For example, the vent units may include surfaces which can be separated on user operation creating an opening for communication of fragrance to the outside environment. By manually adjusting the moveable vent unit, a user can regulate the rate of diffusion of fragrance into the surrounding environment and hence control the strength of scent from the air freshener dispenser.
Alternatively, at least one vent unit is included in the unit, where at least one vent unit is moveable to create an opening between the surface of the vent unit and the base of the dispenser for ventilation of air freshener. For example, the moveable vent may be automatically adjusted on user pumping of the hand lotion dispenser to dispense hand lotion in additional embodiments of the present invention. A preferred dispenser is particularly convenient for private use, as it can be placed anywhere in the home or office and is fully adjustable with respect to dispensing of hand lotion and release of air freshener.
A preferred embodiment also includes an apparatus for combining a hand lotion dispenser and air freshener dispenser in such a manner as to allow dispensing of air freshener actively through a number of optionally non-electrified mechanisms initiated by a user's pump action when dispensing hand lotion. Such an apparatus allows for but removes the need for batteries or electrification of the unit, while providing a controlled, active ability to diffuse fragrance. In one preferred embodiment, depression of the hand lotion pump handle provides a measured quantity of hand lotion as would a standard pump mechanism, but also affects a release of air freshener through compression of a mechanical energy transferring device.
Preferably, within the vent unit, or alternatively in the vent units or base unit, a resilient sponge and, optionally, a flat plate can be placed beneath the air freshener enclosure, where the plate can be attached to the pump tube such that depression of the pump handle depresses both the pump tube and the flat plate. Depression of the flat plate compresses the resilient sponge, allowing the release of fragrance currently held within the sponge to the outside environment through the opening or openings in or between the vent units. When the pump handle is released, the flat plate releases the sponge, and the sponge expands and draws in more fragrance from the air freshener enclosure. A spring may optionally be used to complement the resilient sponge, such that the spring is placed around the pump tube in a manner that the spring is compressed when the pump handle is depressed, and releases its stored energy when the pump handle is released, thus providing greater expansion and fragrance input into the uncompressed sponge. Alternatively, the flat plate may be omitted by the use of an air freshener enclosure having a surface suitable to adequately compress the sponge.
A similar result can be achieved by use of a mechanical fan assembly placed above or below the air freshener enclosure within the vent unit or units. When the pump handle is depressed, the downward force is transferred to the pump tube and the mechanical fan assembly, which translates the downward force into a rotational force acting on the fan. The fan then spins for a brief, adjustable time during which fragrance is drawn from the air freshener enclosure, and between or out of the vent unit or vent units, and or base unit, into the outside environment.
In addition, it is contemplated to substitute a manual pump arrangement for the above-described mechanical fan assembly. In such an arrangement, the vent unit surrounds the upper portion of the base unit and creates a cavity to house the air freshener enclosure. The vent unit is capable of sliding relative to the base unit, so that when the pump handle is depressed, the cavity volume is simultaneously reduced. This forces the air contained therein to be evacuated, and fragrance drawn from the air freshener enclosure to the outside environment, in a manner similar to the mechanical fan assembly. With this arrangement, the vent unit may be depressed individually, thereby releasing fragrance without dispensing hand lotion.
Alternatively, the vent unit may be placed below, and surround a lower portion of the base unit creating a cavity to house the air freshener enclosure below the base unit. In this arrangement, depression of the pump handle would dispense hand lotion, while depression of the base unit itself would force the evacuation of air from the cavity, and draw fragrance from the air freshener enclosure to the outside environment. Such an apparatus allows for active air freshening without the need for batteries, and at the same time allows for adjustment in the strength of fragrance released. As mentioned previously, the active and passive methods may be combined to allow a combination of continuous and user-initiated fragrance release at varying strengths depending on manual adjustment of the dispenser and environmental need.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded perspective view of one embodiment of a hand lotion and air freshener dispenser that utilizes a passive dispersion of air freshener;
FIG. 2 is an exploded perspective view of a second embodiment of a hand lotion and air freshener dispenser that utilizes an active dispersion of air freshener using a sponge method;
FIG. 3 is an exploded perspective view of a third embodiment of a hand lotion and air freshener dispenser with active dispersion of air freshener using a fan method;
FIG. 4 is an exploded perspective view of the fan mechanism of the dispenser of FIG. 3;
FIG. 5 is a perspective view of a fourth embodiment of a hand lotion and air freshener dispenser with active dispersion of air freshener using a manual pump method;
FIG. 6 is a partial cross-section of the dispenser of FIG. 5;
FIG. 7 is a partial cross-section of the dispenser of FIG. 5 in a dual dispensing position;
FIG. 8 is a partial cross-section of the dispenser of FIG. 5 in an air freshener only dispensing position;
FIG. 9 is a partial cross-section of an alternative manual pump dispenser arrangement including support posts having retention heads for retaining carrier pads carrying air freshener;
FIG. 10 is an additional embodiment of a dual dispenser, wherein hand lotion and soap are separately dispensable;
FIGS. 11 and 12 are front and side views, respectively, of an alternative dispenser similar to the dispenser of FIG. 10;
FIGS. 13 and 14 are front and side views, respectively, of another embodiment of a dispenser, which is similar to the dispenser of FIGS. 11 and 12;
FIG. 15 is a dual dispenser in which hand lotion and soap are separately dispensable, with the air freshener being passively dispensed.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference to FIG. 1, one embodiment of a combination hand lotion and air freshener dispenser 10 employing passive diffusion is detailed in an exploded view. The combination dispenser 10 comprises a base unit 53 , with a pump handle 11 which defines a spout 11 a for dispensing of hand lotion as well as a surface 11 b for depression regulating pump action for dispensing of hand lotion. The pump handle 11 is connected to the inner spout tube 12 , which extends from the pump handle 11 to the hand lotion enclosure 50 . The inner spout tube reaches through the hand lotion enclosure opening 51 and then extends into the supply of hand lotion 52 inside the hand lotion enclosure 50 .
The hand lotion enclosure 50 is defined by at least one distinct wall that creates a separate compartment in which hand lotion 52 may sit. Such a compartment may have any cup or bottle shape convenient to hold the hand lotion within the many possible shapes of the present invention. Such a compartment may be enclosed within or form the base unit 53 of the dispenser.
The inner spout tube 12 , below the pump handle 11 , may also be attached to an optional spout seal 13 and optional outer spout tube 14 . When included, the spout seal at least partially surrounds the inner spout tube 12 , and seals the top of the outer spout tube 14 . The outer spout tube 14 surrounds the inner spout tube 12 from the spout seal 13 to some point before or at the end of the inner spout tube 12 in the hand lotion enclosure 50 . As well known in the art, the pump mechanism of 11 , 12 , 13 and 14 creates a pressurized pump region on pressing of the pump handle 11 b by depressing both the inner spout tube 12 which extends all the way to the pump handle 11 and the outer spout tube 14 which is sealed at the spout seal 13 . In this manner hand lotion is dispensed at the pump handle spout 11 a . More generally, any suitable pump mechanism for liquid may be provided.
Between the pump handle 11 and the hand lotion enclosure 50 and base 53 are an upper vent unit 20 and optional lower vent unit 30 . Preferably, the upper vent unit consists of at least one surface at least partially surrounding the inner spout tube 12 and optional outer spout tube 14 , where the optional spout seal 13 attaches to the upper vent unit 20 via a standard screw top, rubberized seal, or similar method known in the art. One or more ventilation holes 21 may be placed in the upper vent unit 20 . Similarly, the lower vent unit 30 may contain one or a number of ventilation holes 31 , where the optional lower vent unit 30 consists of at least one surface at least partially surrounding the inner and optional outer spout tubes 12 and 14 .
The upper ventilation unit 20 is preferably capable of rotation with respect to the lower ventilation unit 30 , as indicated by the arrow 22 in FIG. 1 . The upper ventilation unit 22 is moveable between a fully closed position, where there is substantially no overlap between the vents 21 of the upper ventilation unit 20 and the vents 31 of the lower ventilation unit 30 , and a fully open position, wherein there is substantially complete overlap of the vents 21 and 31 . Additionally, the upper ventilation unit 20 may be positioned at substantially any desired position between the fully open and fully closed position. In this manner, the rate of passive evaporation of air freshener from the air freshener enclosure 40 may be adjusted. Alternatively, the upper vent unit 20 and lower vent unit 30 may be separable to create a ventilation opening between them.
The air freshener enclosure 40 at least partially surrounds the inner 12 and optional outer 14 spout tubes, and may lie between the optional lower vent unit 30 and hand lotion enclosure 50 or base 53 such that the upper 20 or optional lower vent unit 30 or base 53 may serve to completely enshroud the air freshener enclosure 40 . The air freshener enclosure 40 may be removable 41 , for example, by lifting the optional lower 30 and upper 20 vent units in order to expose the air freshener enclosure. In one of many variations of this embodiment, the air freshener enclosure 40 may lie between the upper vent unit 20 and optional lower vent unit 30 , or between the upper vent unit 20 and hand lotion enclosure 50 or base 53 .
The air freshener enclosure 40 may consist of fragrance suspended in a carrier, may expose a polyester matrix on one or more surfaces to allow evaporation of fragrance, and or may itself have one or a number of openings for release of fragrance. The air freshener enclosure 40 is preferably small enough to fit within the vent units 20 or 30 , and base unit 53 , and conform to one of the many shapes possible for the present invention.
A second embodiment of a dispenser 10 is illustrated in FIG. 2. A standard pump apparatus consisting of a pump handle 11 with pump spout 11 a and a surface 11 b for compression to initiate pump action is connected to an inner spout tube 12 . The optional spout seal 13 similarly at least partially surrounds the inner spout tube 12 and seals the end of the optional outer spout tube 14 .
The upper vent unit 20 and optional lower vent unit 30 may be similar to the first embodiment, except the vent unit or units 20 and 30 serve to enclose the air freshener enclosure 40 , an optional circular plate defining a surface 60 , and a resilient sponge 70 . The three components 40 , 60 and 70 may be placed in any order between the upper and lower vent units 20 and 30 , but the placement of the air freshener enclosure 40 above the plate surface 60 , with the plate surface 60 itself above the sponge 70 , is preferred. Alternatively, the optional plate surface 60 may be omitted, and substituted with an air freshener enclosure 40 equipped with an appropriate surface to compress the resilient sponge 70 . Thus, when such an arrangement is used, the air freshener enclosure 40 effectively functions as both an air freshening device and as the plate surface 60 .
The air freshener enclosure 40 contains fragrance usually suspended in a carrier, and may be optionally removable. The air freshener enclosure 40 at least partially surrounds the inner 12 and optional outer 14 spout tubes and, in at least one preferred embodiment, does not move when the pump handle 11 is depressed 11 b . It is small enough to fit within the vent unit or units 20 and or 30 , and the base unit 53 , and otherwise conforms to one of the many shapes possible for the current invention. The plate surface 60 is attached to the optional outer 14 and or inner 12 spout tubes such that when the pump handle 11 is depressed, the plate surface 60 is depressed 60 b . The plate surface 60 at least partially surrounds the optional outer 14 and inner 12 spout tubes and when depressed 60 b compresses the sponge 70 b.
The resilient sponge 70 at least partially surrounds the optional outer 14 and inner 12 spout tube, and is sufficiently porous to allow air to leave the sponge when compressed and fill the sponge when decompressed. When the pump handle 11 is depressed 11 b , the plate surface 60 compresses the sponge, releasing the air and air freshener stored within it through or between the ventilation unit or units 20 and 30 and/or the base unit 53 , and out into the external environment 5 .
When the pump handle 11 is released, the plate 60 lifts, the sponge 70 decompresses, and fragrance from the air freshener enclosure 40 is drawn into the sponge 70 from the resulting pump action. This embodiment may also combine the sponge 70 and air freshener enclosure 40 in the base unit 53 , or release fragrance by drawing apart the upper and lower ventilation units 20 and 30 upon pump action 11 b . Alternatively, fragrance may be released by drawing apart the upper ventilation unit 20 from the base unit 53 with or without the use of ventilation holes 21 . Upon pump action 11 b , hand lotion 52 is dispensed through the inner spout tube 12 and out the pump handle spout 11 a.
Optionally, the hand lotion pump handle 11 may be rotated to turn off dispensing hand lotion 11 a by use of an optional valve 15 (illustrated schematically in FIG. 2) at the joint of the pump handle 11 and the inner spout tube 12 , as is known in the art. Thus, the pump action of the handle 11 b can be used to indirectly power air freshener dispersion without dispensing hand lotion. Optionally and similarly, the hand lotion pump handle 11 may be rotated to prevent transfer of mechanical energy from pump action 11 b to the mechanical energy transfer device to prevent active dispersion of air freshener while dispensing hand lotion.
In FIGS. 3 and 4, another embodiment of a preferred dispenser 10 is shown. In this embodiment, the lower vent unit 30 may also contain a mechanical fan assembly 55 , which comprises: a spring 32 , a fan 33 , and a helical gear 34 (FIG. 5 ). The helical gear 34 may be attached to, or defined by the inner spout tube 12 and mates with helical threading of the fan 33 to translate linear motion of the inner spout tube 12 into rotational motion of the fan 33 . As the fan 33 turns 33 a , an air freshener enclosure 40 evaporates more aggressively due to the action of the fan 33 and disperses through or between the optional lower 30 and/or upper 20 vent units, or between the upper vent unit 20 and base unit 53 , into the surrounding environment 5 .
Upon compression of the pump handle 11 , in addition to turning the fan 33 , the inner spout tube 12 and optional outer spout tube 14 are moved in a manner where the optional outer spout tube 14 , or alternatively the inner spout tube 12 , compresses the spring 32 . Upon release of the pump handle 11 , the spring 32 assists in restoring the dispenser 10 to its original position and prepares it for further use. By adjusting the helical gear 34 , manually adjusting 22 the upper vent, or placing a stronger or weaker air freshener enclosure 40 in the invention, the rate of evaporation and strength of fragrance dispersed into the external environment 5 can be optionally adjusted.
FIG. 5 illustrates an additional embodiment of a preferred dispenser in which air freshener is actively dispensed upon user-initiated dispensing of hand lotion. In addition, the dispenser of FIG. 5 is capable of actively dispensing air freshener independently of dispensing hand lotion. This arrangement advantageously permits both simultaneous dispensing of air freshener and hand lotion for convenience, while allowing the same dispenser to be used for active dispensing of air freshener alone, at such times when odor control is desired while the use of hand lotion is not necessary or desired.
In the embodiment of FIG. 5, the upper vent, or hood, 20 partially covers the base unit 53 so as to create a cavity, or enclosure, 37 between them for placement of an air freshener assembly 60 . The hood 20 includes an upwardly extending neck portion 19 , which is contacted by the pump assembly 11 to move the hood 20 downward upon actuation of the pump assembly 11 . Desirably, the base unit 53 includes a recessed upper portion 61 generally corresponding with the coverage of the hood 20 . This allows the outer surface of the hood 20 to be substantially flush with the outer surface of the base unit 53 and provides for an aesthetically pleasing outward appearance.
Preferably, the hood 20 is engaged with the air freshener assembly 60 to substantially seal the cavity 37 , while still allowing relative motion between the hood 20 and air freshener assembly 60 . A spring 62 biases the hood 20 into an uppermost, or non-dispensing position. The illustrated spring 62 is a helical coil spring, however, other suitable types of springs may also be used. Preferably, the spring rate of the spring 62 is selected such that the hood 20 is quickly returned to the uppermost position when the pump handle 11 is released, yet allows the hood 20 to be moved into the dispensing position without requiring excessive downward pressure.
The air freshener assembly 60 is supported on the upper surface of the base unit 53 . The hand lotion enclosure opening 51 extends upward through a central opening 64 in the air freshener assembly 60 . Preferably, the hand lotion enclosure opening 51 is defined by a substantially cylindrical neck 54 and communicates with the interior space of the base unit 53 . The neck 54 preferably includes external threads 56 that mate with internal threads 75 of a threaded cap 76 of the pump 11 .
Preferably, the air freshener assembly 60 includes a plurality of tabs 64 extending downward over an upper portion of the base unit 53 . The inner surfaces of each tab 64 defines an abutment surface which contacts the base unit 53 and inhibits the air freshener assembly 60 from rotating relative to the base unit 53 . Preferably, four tabs 64 are provided with two on each side spaced from the central axis of the dispenser. Advantageously, this feature allows a threaded pump assembly to be assembled to the base unit 53 without causing rotation of the air freshener assembly 60 .
FIGS. 6-9, an alternative embodiment of a dispenser 10 is shown in partial cross-section. The dispenser 10 of FIG. 6 is similar to the dispenser of FIG. 5, with the exception that the neck portion 19 of the hood 20 has been omitted. However, the dispenser 10 of FIGS. 6-9 may optionally include a neck portion 19 , if desired, while still performing substantially as described. The air freshener assembly 60 comprises a tray 66 which supports two carrier pads 68 . The carrier pads 68 are preferably made of a polyester matrix and carry the supply of air freshener. However, other suitable, preferably porous, carrier materials may be used. A pair of projections, or support posts, 70 extend upward from the upper surface of the tray 66 . The support posts 70 pass through an aperture 72 in the carrier pads 68 to position the pads 68 with respect to the tray 66 and prevent the pads 68 from moving during shipment or use of the dispenser 10 . However, the support posts 70 permit the carrier pads 68 to be deliberately removed so that the pads 68 may be replaced. Preferably, the support posts 70 have a generally “X” shaped cross-section (FIG. 5) for ease of manufacturing, however, other suitable configurations may also be utilized.
A central flange portion 74 of the tray 66 is held between the upper surface of the base assembly 53 and a threaded cap 76 of the pump 11 thereby securing the tray 66 to the base assembly 53 . The tray 66 defines a lip 78 about its periphery. The lip 78 is slideably engaged with the inner surface of the upper vent unit 20 to substantially seal the cavity 37 , as described above. Preferably, the lip 78 is curved to allow easier movement of the hood, or upper vent, 20 .
With reference to FIG. 7, the dispenser of FIG. 5 is illustrated in a dual dispensing mode. When the pump handle 11 is pressed downward to dispense hand lotion, the upper vent 20 is simultaneously moved downward. As a result, the volume of the cavity 37 is decreased, thereby expelling a portion of air within cavity 37 , which contains fragrance, through the vents 21 . Preferably, the downward travel of the upper vent unit 20 is approximately ¾ inches, however, other suitable travel distances may also be used. Thus, in the dual dispensing mode of FIG. 7, fragrance is actively dispensed simultaneously with the dispensing of hand lotion. Additionally, the fragrance is dispensed by the same downward pressure that dispenses the hand lotion.
Additionally, when the pump handle 11 and vent unit 20 are moved downward, the spring 62 is compressed. Upon release of the pump handle 11 , the stored energy within the spring 62 is released thereby moving the vent unit 20 relative to the base unit 53 so as to increase the volume of the cavity 37 . A fresh supply of air is drawn into the cavity 37 through the vents 21 . The fresh air drawn into the cavity 37 increases the rate of evaporation of the air freshener supply within the carrier pads 68 , thus increasing the fragrance within the cavity 37 and preparing the dispenser 10 for further use.
With reference to FIG. 8, the dispenser of FIG. 5 is illustrated in an air freshener dispensing mode. In this mode, a downward pressure is applied to the upper vent unit 20 thereby moving the vent unit 20 in a downward direction while the pump handle 11 remains in an uppermost, or non-dispensing position. Air freshener is dispensed from the cavity 37 in a manner substantially as described above, without dispensing hand lotion.
FIG. 9 is a dispenser substantially identical to the dispenser of FIG. 5, except that the support posts 70 originate from the base unit 53 , rather than being connected to the tray 66 . The support posts 70 pass through corresponding apertures 80 in the tray 66 . In addition, a retention head 82 is provided on the upper end of each support post 70 . Each retention head 82 defines a retention surface 84 for retaining the carrier pad 68 onto the support post 70 .
The retention heads 82 are preferably sized slightly larger than the apertures 72 of the carrier pads 68 such that the carrier pads 68 can be assembled onto the support posts 70 over the retention heads 82 , while the retention surfaces 84 provide resistance against the carrier pads 68 being removed from the support posts 70 . Advantageously, with such an arrangement, accidental removal of the carrier pads 68 by young children is inhibited.
FIG. 10 is an additional embodiment of an active air freshener dispenser 10 . In the illustrated embodiment, a vent unit 20 is constructed to slidingly receive the base unit 53 of the dispenser 10 . Preferably, an air freshener enclosure 40 , as described above, is placed within a cavity 37 defined between the vent unit 20 and the base unit 53 . A spring 32 is operably positioned between the vent unit 20 and the base unit 53 to bias the base unit 53 into an upward position. The pump handle 11 may be depressed to dispense hand lotion in a known manner. The base unit 53 may be pressed downward to actively dispense air freshener in a manner substantially as described above. The spring 32 advantageously assist the base unit 53 in moving to an upward position, thus preparing the dispenser 10 for further use.
Advantageously, the vent unit 20 may be configured to receive a standard, commercially available hand lotion dispenser. Thus, the standard dispenser would serve as the base unit 53 . Such an arrangement would allow convenient replacement of the base unit 53 with a variety of products that are commercially available in a standard pump dispenser, such as hand soap or hand sanitizer, for example.
The vent unit 20 may be configured in a variety of shapes and sizes. For example, FIGS. 11 and 12 illustrate front and side views, respectively, of a vent unit 20 having a substantially trapezoidal shape in both the front and side views. In addition, the upper end of the vent unit 20 comprises a curvilinear shape for aesthetic appeal.
FIGS. 13 and 14 illustrate front and side views, respectively, of an alternative embodiment of a vent unit 20 for receiving a standard pump dispenser. The vent unit 20 of FIGS. 13 and 14 comprise a generally rounded shape in both the front and side views. In addition, the vent unit 20 includes a generally triangular central cutout in both the front and side of its upper end. Preferably, the triangular cutout is also provided in the back and hidden side.
FIG. 15 illustrates a passive embodiment of a vent unit 20 for receiving a standard pump dispenser. The standard dispenser is received in the vent unit 20 in a fixed manner. That is, the cavity 37 defined therebetween is not variable in volume. However, an adjuster ring 86 is positioned over the vents 21 provided in the vent unit 20 to allow adjustment of the rate of air freshener dispensing. The adjuster ring 86 is rotatably engaged on the vent unit 20 and provided with a plurality of vents 88 , which preferably correspond in size, shape and placement with the vents 21 . The adjuster ring 86 can be moved from a fully closed position, in which the vents 21 are fully closed, to a fully open position, wherein the vents 21 and vents 88 are substantially aligned.
Preferred embodiments may take any shape practical for dispensing of hand lotion, soap or other personal care products. Thus, it is foreseen that the present invention could take the shape of any generally available consumer pump unit, a wall or table mounted unit, a portable unit for purse or automobile, or permanent unit with replaceable enclosures for air freshener and hand lotion. Such permanent units can be, for example, ceramic, glass, stone or plastic home design units with varying themes, pictures, or sculpted in any shape, or an ordinary commercial unit.
A preferred embodiment uses air freshener and hand lotion. Any commercially available hand lotion may be used. One preferred air freshener enclosure may contain a fragrance manufactured by Premier Specialties, Inc. of Middlesex, N.J. and may be fragrance #PSI-01842. If necessary, fragrance can be mixed with a volatile carrier such as an odorless hydrocarbon solvent (e.g., ISOPAR G manufactured by the Exxon Corp). As discussed above, however, in the United States limits are placed on Volatile Organic Compound (VOC) content in consumer products, including air fresheners. Therefore, an air freshener used in the United States must be designed and formulated to obey VOC limits.
Although this invention has been described in terms of certain preferred embodiments, other embodiments that are apparent to those of ordinary skill in the art are also within the scope of this invention. For example, the dispensing of other liquids, the electrification of the current invention, application to a vertical wall or horizontal countertop mountable unit, and use of other dispensing methods besides a pump are considered part of this invention. Accordingly, the scope of the invention is intended to be defined by the claims that follow. | A method and apparatus for dispensing of hand lotion and air freshener in a combined unit for home and office. Air freshener may be passively dispersed at a controlled rate from the apparatus, or may be actively dispersed when a user pumps the apparatus to receive a measured quantity of hand lotion. Dispersion may be implemented using a mechanical fan or compression of a sponge, for example. | 1 |
[0001] This application is a continuation of pending application Ser. No. 10/107,949, filed Mar. 27, 2002, now U.S. Pat. No. 7,031,962, the contents of which are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention provides a system and method for managing objects and resources with access rights embedded in nodes within a hierarchical tree structure. The system is suitable for implementation of HL7-approved XML standards for medical records and/or messages.
BACKGROUND OF THE INVENTION
[0003] Controlling the access of a large number of users to a vast array of data represents one of the greatest challenges facing the future of the Internet. One example of an immense access control undertaking that will exceed the capabilities of current access control systems relates to the provisions of the Health Insurance Portability and Accountability Act of 1996 (HIPAA).
[0004] HIPAA will be implemented in accordance with a Rule (Federal Register/Vol. 65, No. 250/Thursday, Dec. 28, 2000/Rules and Regulations p. 82462, 45 CFR Parts 160 and 164, Rin: 0991-AB08, Standards for Privacy of Individually Identifiable Health Information) promulgated by the Department of Health and Human Services (HHS) in an effort to achieve the adoption of industry standards for the electronic transmission of health information. In short, HIPAA requires that all patient information transfers between organizations be in a standardized form and that standards of privacy be maintained. Health Level 7 (HL7) is an organization that creates the standards for storage and interchange of medical records encompassed by HIPAA. Standardization complications include the fact that there are currently about 400 formats for electronic health care claims processing in use nationwide. Further, the need to manage this information will require finely granular (down to the per field level) access to a massively scaled number of records. This access must obey the mandated confidentiality and respect specific patient confidentiality requests.
[0005] HL7 has chosen the extensible Markup Language (XML) as the basis for structuring medical records for storage and messaging. This language organizes data as a tree structure documents. XML is standardized by W3C, (http://www.w3.org/TRIREC-xml). W3C is an international industry consortium responsible for developing common code standards for the World Wide Web.
[0006] Applications storing or transferring medical records will require access control mechanisms to assure that HIPAA requirements are met. It is an object of the present invention to supply this need.
[0007] U.S. Pat. No. 6,061,684, “Method and system for controlling user access to a resource in a networked computing environment,” assigned to Microsoft Corporation (Redmond, Wash.), describes a unified and straightforward approach to managing file and other resource security in a networked computing environment. The invention can be implemented in a multi-user computer network that includes a client computer, a server computer that controls a resource sharable among users of the network, such as a shared file folder or directory, and a communications pathway between the client computer and the server computer. The resource is organized as a hierarchy of elements with a root element at the top of the hierarchy and additional elements below the root element. According to the invention, a request is received to change a protection, such as an access permission, of an element of the resource hierarchy (other than the root) with respect to a particular network user. If the element in question lacks an associated access control list, a nearest ancestor element of the hierarchy is located that has an associated access control list. The first (descendant) element inherits the access control list of the second (ancestor) element. This inheritance is done by generating a copy of the access control list of the second element and associating the generated copy with the first element. The requested change in protection is then incorporated into the generated copy that has been associated with the first element so as to establish an updated access control list for the first element. Further, the requested change can be propagated downwards in the hierarchy from the first element to its descendants having access control lists.
[0008] U.S. Pat. No. 6,038,563, “System and method for restricting database access to managed object information using a permissions table that specifies access rights corresponding to user access rights to the managed objects,” assigned to Sun Microsystems, Inc. (Palo Alto, Calif.), describes an access control database that specifies access rights by users to specified sets of the managed objects. The specified access rights include access rights to obtain management information from the network. An access control server provides users access to the managed objects in accordance with the access rights specified by the access control database. An information transfer mechanism sends management information from the network to a database management system (DBMS) for storage in a set of database tables. Each database table stores management information for a corresponding class of managed objects. An access control procedure limits access to the management information stored in the database tables using at least one permissions table. A permissions table defines a subset of rows in the database tables that are accessible to at least one of the users. The set of database table rows that are accessible corresponds to the managed object access rights specified by the access control database. A user access request to access management information in the database is intercepted, and the access control procedure is invoked when the user access request is a select statement. The database access engine accesses information in the set of database tables using the permissions tables such that each user is allowed access only to management information in the set of database tables that the user would be allowed by the access control database to access.
[0009] U.S. Pat. No. 5,878,415, “Controlling access to objects in a hierarchical database,” assigned to Novell, Inc. (Provo, Utah), describes methods and systems for controlling access to objects in a hierarchical database. The database may include a directory services repository, and/or synchronized partitions. An access constraint propagator reads an access control property of an ancestor of a target object. The access control property designates an inheritable access constraint such as an object class filter or an “inheritable” flag. The object class filter restricts a grant of rights to objects of an identified class. The “inheritable” flag allows inheritance of an access constraint on a specific object property. The propagator enforces the inheritable access constraint by applying it to at least the target object.
SUMMARY OF THE INVENTION
[0010] In one aspect, the present invention comprises a system for managing objects and resources with access rights embedded in nodes within a hierarchical tree-structure. The system includes a host, housing a Web server, a database server, an entitlement server, and a transaction server; a network, such as the Internet or an intranet; and one or more client PCs.
[0011] In another aspect, the present invention comprises a method of inputting a transaction in XML form for use in the determination and granting of access rights embedded in nodes within a hierarchical tree structure. The method includes receiving transaction data from the external system; parsing and validating the XML; determining whether the received data is valid; adding access data to the entitlement server and text content to the database server; determining whether an error occurred; sending an error message to the external system; and sending a confirmation message to the external system.
[0012] In yet another aspect, the present invention comprises a method of interacting with a host system into which an XML document has been accepted. The method includes identifying the user accessing the host using a client PC; receiving a request; determining whether an access check is needed; determining whether permission should be granted; performing the request; replying to the user; and handling the denial of the request.
[0013] One advantage of the present invention is that it provides a way to protect objects described by a tree structure.
[0014] A second advantage of the present invention is that it provides a way to protect objects with as much granularity as the tree structure permits.
[0015] A third advantage of the present invention is that it provides a way to protect objects with as much granularity as the set of users permits.
[0016] A fourth advantage of the present invention is that the entitlement IDs (or expressions or objects) can be defined in a diverse ways, allowing for a wide variety of applications.
[0017] A fifth advantage of the present invention is that the entitlement IDs may be collected separately, meaning that they do not need to be sprinkled throughout the code structure. They can be cached before the XML is parsed, leading to improved system speed and efficiency.
[0018] A sixth advantage of the present invention is that may be packaged either as a separate XML document or as a separate part of the document containing the objects to protect.
BRIEF DESCRIPTION OF THE DRAWING
[0019] The invention is described with reference to the several figures of the drawing, in which,
[0020] FIG. 1 shows a system for managing objects and resources in a hierarchy with access rights embedded in nodes;
[0021] FIG. 2 is a flow chart illustrating a method of inputting a transaction in XML form;
[0022] FIG. 3 is a flow chart illustrating a method of interacting with a host system into which the XML document has been accepted; and
[0023] FIG. 4 illustrates the used of XML to manage objects and resources in a hierarchy with access rights embedded in some nodes.
DETAILED DESCRIPTION
[0024] FIG. 1 illustrates a system for managing objects and resources in a hierarchy with access rights embedded in nodes. System 100 includes a host 105 , comprising a Web server 110 , a database server 120 , an entitlement server 130 , and a transaction server 140 , which are all interconnected within host 105 . Host 105 can be either a single computer, or a series of computers operating in concert. System 100 also includes connections to a network 150 (such as the Internet or an intranet), through which an external system 160 , and one or more client PCs 170 connect with host 105 .
[0025] In some embodiments of the invention, external system 160 and client PCs 170 use network 150 to communicate with host 105 for the purposes of generating and receiving documents programmed in XML. In other embodiments, client PCs 170 need never actually create or access XML directly. Instead, web server 110 invokes transaction server 140 to request text from an XML document, and then transforms the text into HTML to send back to the client PC 170 .
[0026] Typically, client PC 170 is a personal computer. External system 160 may be a peer to host 105 or a host-type system of wholly separate elements; however, external system 160 must contain an application capable of generating and translating XML. Host 105 represents a network-connected host environment consisting of one or more servers. Web server 110 , which may be a single server or multiple servers operating in a cluster, executes the functions associated with serving World Wide Web pages. Database server 120 stores the actual content of the XML transactions and is called upon by other elements of host 105 for such content. The internal form of the content need not be XML as long as the tree structuring information is preserved. Entitlement server 130 operates as one type of a database server dedicated to hosting and adjudicating access control for applications served by host 105 . The functionality of one suitable entitlement server 130 is fully described in U.S. Pat. No. 6,154,741 to Feldman, which is assigned to EntitleNet, Inc., and incorporated herein by reference. Transaction server 140 functions as the XML interpreter, and houses various software applications for that purpose, including those that pass portions of submitted XML documents to entitlement server 130 and database server 120 for storage. Transaction server 140 also receives transaction results from entitlement server 130 and database server 120 and responds accordingly to the transaction's requester. In addition, transaction server 140 governs the retrieval of requested portions of XML documents.
[0027] FIG. 2 is a flowchart illustrating a method of inputting a transaction in XML form. Entitlement information within the XML affects the exchange with respect to the way permission to access information is granted. Method 200 includes the following steps:
[0000] Step 210 : Receiving Transaction Data
[0028] In this step, transaction server 140 receives an XML document with associated transaction data generated by external system 160 . External system 160 sends this XML document to transaction server 140 via network 150 .
[0000] Step 220 : Parsing and Validating XML
[0029] In this step, transaction server 140 parses the received XML document to check for validity using software applications and techniques well known in the art.
[0000] Step 230 : Are the Data Valid?
[0030] In this decision step, transaction server 140 determines whether the XML document is valid. If yes, process 200 proceeds to step 240 ; if no, process 200 proceeds to step 260 .
[0000] Step 240 : Adding Access Data to Entitlement Server and Text Content to Database Server
[0031] In this step, transaction server 140 translates the information parsed in step 220 into the appropriate internal form and stores it on entitlement server 130 and database server 120 . In particular, access information is added to entitlement server 130 , and the text information is saved to database server 120 . In addition, some tracking information is added to database server 120 to track the processing performed.
[0000] Step 250 : Did an Error Occur?
[0032] In this decision step, transaction server 140 checks to see if any errors occurred thus far. If yes, process 200 proceeds to step 260 ; if no, process 200 proceeds to step 270 .
[0000] Step 260 : Sending Error Message
[0033] In this step, transaction server 140 sends an error message back to the originating external system 160 via network 150 , and processing ends.
[0000] Step 270 : Sending Confirmation Message
[0034] In this step, transaction server 140 sends a confirmation message back to originating external system 160 via network 150 , and processing ends.
[0035] FIG. 3 is a flowchart illustrating a method of interacting with a host system into which the XML document has been accepted. While FIG. 2 covered the programmatic interface with host 105 using external system 160 , FIG. 3 instead covers the interaction of client PCs 170 with host 105 . Method 300 includes the following steps:
[0000] Step 310 : Authenticating User
[0036] In this step, Web server 110 authenticates users on client PC 170 talking to host 105 using network 150 and applications known in the art, such as using a secure socket layer interchange.
[0000] Step 320 : Receiving Request
[0037] In this step, Web server 110 receives a request for information from a user using Web-browsing software installed on client PC 170 .
[0000] Step 330 : Is an Access Check Needed?
[0038] In this decision step, Web server 110 determines whether the information request requires an access control check. If yes, process 300 proceeds to step 340 ; if no, process 300 proceeds to step 380 .
[0000] Step 340 : Is Permission Granted?
[0039] In this decision step, entitlement server 130 determines whether to grant access based on user identification obtained in step 310 and the access check performed in step 330 . If yes, process 300 proceeds to step 350 ; if no, process 300 proceeds to step 370 .
[0000] Step 350 : Performing Request
[0040] In this step, entitlement server 130 performs the request received from Web server 110 . The performance of this request (or adjudication) is fully described in U.S. Pat. No. 6,154,741 assigned to EntitleNet, Inc.
[0000] Step 360 : Replying to User
[0041] In this step, Web server 110 sends a reply to the request for information originating from client PC 170 via network 150 , and processing ends.
[0000] Step 370 : Handling Denial
[0042] In this step, Web server 110 handles the denial of access to information (i.e., the user on client PC 170 is not allowed to receive the information requested) by communicating with client PC 170 via network 150 , and processing ends.
[0043] FIG. 4 illustrates the use of XML to manage objects and resources in a hierarchy with access rights embedded in some nodes. An entitlementID element creates a BMAP object with a name given by the ID attribute and entitles it with the entitlement expression given by the V attribute. (The names are arbitrary and chosen for the purposes of exposition.) An arbitrary number of these may be defined to yield any desired granularity.
[0044] An entitlement attribute within an element specifies the entitlementID governing the element. Entitlements are enforced in a tree-oriented manner with lower or enclosed elements of the tree governed by the enclosing nodes. An exception to this is that an entitlement attribute on an element supercedes the entitlement of higher nodes. This presents two constructs which, when used in concert, allow the specification of the control of access to portions of an XML data structure.
[0045] 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 system and method for controlling access to data within a hierarchically organized document, such as an XML document. Elements may have their access rights specified, for example as a variable in an XML tag. If not specified within an element of the document, access rights are inherited from its nearest ancestor. Specified access rights may refer to a collection of entitlement expressions, which describe with arbitrarily fine granularity which users and user types may access the data. | 8 |
CROSS-REFERENCE TO RELATED APPLICATION
This application claims priority pursuant to 35 U.S.C. §119(e) to U.S. Provisional Application Ser. No. 60/367,792, filed Mar. 26, 2002.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to electronic circuits, and, more specifically, to phase detection circuits.
2. Description of Related Art
A PLL (phase locked loop ) refers to a feedback loop in which the input and the feedback parameters of interest are the relative phases of the waveforms. The function of a PLL is to track small differences in phase between the input and feedback signal. A conventional PLL typically includes a phase detector, low-pass filter and a VCO (voltage-controlled oscillator). The phase detector measures the phase difference between its two inputs. The phase detector output is then filtered by the low-pass filter and applied to the VCO. The VCO input voltage changes the VCO frequency in a direction that reduces the phase difference between the input signal and the local oscillator. The loop is in phase lock or locked when the phase difference between the input signal and the VCO frequency is reduced to zero.
A phase detector only accepts phase information in comparing two signals. A PFD (phase/frequency detector) is also able to accept frequency information in comparing two signals. A digital PLL is a PLL system in which the VCO and loop filter are built from digital components such as gates or flip-flops. A PFD is typically made from an exclusive OR gate, or an AND gate and D-type flip-flops or a tri-state phase/frequency comparator. PLL circuits have two ranges for acquisition, a pull-in range and a capture range (also known as lock-in range). The acquisition time is the total time the PLL takes to acquire both frequency and phase lock.
A PLL circuit will produce the lowest output jitter level if it can perform phase comparisons and can phase lock using the highest input clock available. As phase measurements become more regular, the loop is updated more regularly and control is thereby maintained to reduce internal noise. Unfortunately, some systems, such as telecommunications networks, require the PLL system to be tolerant to a large amount of jitter on the clock input and still be able to maintain a lock. To maintain a lock, the system must remember the location of the 0° position and continuously pull the PLL in the direction of that location. Often the required jitter tolerance values will extend to tens of clock cycles or unit intervals (1 unit interval (UI)=1 clock cycle=360°). A conventional PLL would not be able to maintain a lock with over ±1 UI of jitter on the input. Thus, with ±10 UI of input jitter, the PLL would not know the location of the original 0° position and, as a result, cycle slippage would occur. Cycle slippage causes timing problems for the system, such as, for example, buffer overflows. Accordingly, conventional PLL circuits may not meet the requirements of systems that require a high jitter tolerance, such as telecommunications systems. Jitter tolerance is particularly difficult to provide in high frequency applications. Conventional techniques for providing jitter tolerance for high frequency applications include dividing the clock down to a fraction of the original frequency. Although the lower frequency results in proportionately lower jitter, the system suffers a loss in performance.
FIG. 10 shows a conventional type-4 PFD, indicated generally at 500 , with a pair of output sampling DFF (D-type flip flop) units 505 and 510 (“Down_s” and “Up_s”, respectively). The output sampling DFF units 505 and 510 are optional and would not be needed in an APLL (analog PLL) system. Note that AND gate 525 (“I1”) and inverter 530 (“I2”), shown in FIG. 10, are idealized representations and in reality would incorporate some delay so that the reset pulse lasts for a sufficient duration, typically a few nanoseconds, to effectively reset DFF units 535 and 540 . Generally, the output of DFF units 535 and 540 each go high on the leading edge of their respective clock inputs and remain high until they are reset. The reset signal occurs when inputs A 515 and B 520 have both gone from a low to a high state, which makes signals ‘up’ and ‘down’ both high. When both input signals A 515 and B 520 are in phase and of the same frequency, both outputs will be low for most of the time, with signals ‘up’ and ‘down’ both pulsing high only for a few nanoseconds, and no signal will be applied to the VCO (not shown in FIG. 10 ). If the two signal frequencies are not the same, then the output pulse widths will depend on both the relative frequency difference and the phase difference. The type-4 PFD 500 is common because of its simplicity, accuracy and ability to perform both frequency and phase locking. But, the phase capture range of the type-4 PFD is generally limited to ±360°.
FIGS. 11 and 12 show timing diagrams that illustrate the behavior of conventional PFD 500 shown in FIG. 10 . If the rising edge of input A 515 , shown in FIG. 11, occurs before the rising edge of input B 520 , then the “up” pulse is wider than the “down” pulse, as shown in FIG. 11 . The width of the up pulse is proportional to the phase difference between input A 515 and input B 520 . Conversely, if the rising edge of input B 520 occurs before the rising edge of input A 515 , then the down pulse is wider and has a width proportional to the phase difference. An inspection of FIG. 10 in conjunction with the timing diagrams shown in FIGS. 11-12 reveals that the inherent range of the conventional PFD 500 is limited to one cycle or UI as discussed above. The diagram shown in FIG. 12 shows the waveforms at the extreme ±360° limit. Beyond this limit, the signal begins to resemble that of FIG. 11 . At this point, the 0° reference point has been lost and a cycle slip has occurred. Thus, PFD 500 is unable to operate past ±360°. Therefore it would be desirable to provide a phase detection circuit that provides an operating range that extends beyond ±360° and provides a large amount of jitter tolerance.
SUMMARY OF THE INVENTION
The present invention provides a phase detection circuit that allows the capture range, lock range and jitter tolerance to be extended beyond the ±360° limit associated with conventional PLL circuits. In an embodiment of the invention, the phase detection circuit includes a PFD (phase and frequency detector) that operates in the ±540° range.
In another exemplary embodiment of the invention, the phase detection system combines two types of phase detectors, including a coarse phase detector and a fine phase detector, e.g., the PFD, in an advantageous manner. The phase detection system uses the coarse phase detector, e.g., a digital cycle slip counter phase detector, to provide a wide phase capture and lock range for a large jitter tolerance. The phase detection system combines this detector with a fine phase measurement from the PFD for very accurate phase control and low output jitter.
The PFD allows the coarse phase detector to precondition the PFD so that the coarse and fine detectors work together with no conflict in responses and no dead-band, e.g., phase ranges not captured by either detector. The capture range for the presently disclosed phase detection circuit may be extended in programmable amounts up to several thousand clock cycles or can be set to any desired maximum capture range in steps of 360°. In an exemplary embodiment of the invention, the system and method of the present invention may be implemented in PLL systems that have some digital component such that the logical merging and arithmetic combining of phase detector results may be more easily accomplished with the digital components than with analog components.
The presently disclosed phase detection system provides a number of advantages over conventional phase detection circuits. One advantage of the present phase detection system is a wide phase capture and lock range with an unlimited maximum phase capture range. Another advantage is that the system provides accurate phase measurement in addition to the wide range. An additional advantage of the present system is a frequency lock capability. A further advantage of the present invention is the easy programmability of a maximum capture range. Another advantage of the present invention is the relative ease of programming additional options for a ±180°, ±360° or ±540° phase range. In addition, users may program additional options for ranges in multiples of 360°. Yet another advantage of the present invention is that the system may be implemented in both digital and analog systems even though some of the techniques used may be digital.
A more complete understanding of the present invention will be afforded to those skilled in the art, as well as a realization of additional advantages and objects thereof, by a consideration of the following detailed description of the preferred embodiment. Reference will be made to the appended sheets of drawings which will first be described briefly.
BRIEF DESCRIPTION OF THE DRAWINGS
The present disclosure and its numerous objects, features, and advantages may be better understood by reference to the following description of an illustrative embodiment, taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a block diagram of an exemplary embodiment of the phase frequency detector (PFD);
FIGS. 2A and 2B show an exemplary embodiment of the PFD;
FIG. 3 is a timing diagram illustrating the performance of an exemplary embodiment of the PFD at a +90° input phase difference;
FIG. 4 is a timing diagram illustrating the performance of an exemplary embodiment of the PFD at a +270° input phase difference;
FIG. 5 is a timing diagram illustrating the performance of an exemplary embodiment of the PFD at a +450° input phase difference;
FIG. 6 is a timing diagram illustrating the performance of an exemplary embodiment of the PFD at approximately a +540° input phase difference;
FIG. 7 is a timing diagram illustrating the performance of an exemplary embodiment of the PFD from a +90° to a +540° input phase difference and back to a 0° position;
FIG. 8 is an exemplary embodiment of a system incorporating a digital phase detection scheme with the PFD;
FIG. 9 is a timing diagram illustrating the performance of the system shown in FIG. 7 during a phase sweep from 0 to 250 UI (900°) and back to a 0° position;
FIG. 10 shows a prior art PFD;
FIG. 11 is a timing diagram illustrating the performance of the prior art PFD with a minor phase difference; and
FIG. 12 is a timing diagram illustrating the performance of the prior art PFD at the 360° phase difference limit.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention satisfies the need to provide a PFD that allows the capture range, lock range and jitter tolerance to be extended beyond the ±360° limit associated with conventional phase detection circuits. In the detailed description that follows, like element numerals are used to describe like elements illustrated in one or more of the drawings.
FIG. 1 shows a block diagram of an exemplary embodiment of the PFD of the present invention, indicated generally at 10 . PFD 10 detects the phase and frequency differences between a first input signal 15 (input signal B) and a second input signal 20 (input signal A). PFD 10 contains a first stage down phase capture unit 315 to capture negative phase differences down to −360°. The output of first stage down phase capture unit 315 goes active when it detects an input B 15 rising edge. First stage down phase capture unit 315 is connected to a second stage down phase capture unit 325 . The output of second stage down phase capture unit 325 may go active when a second input B 15 rising edge is detected at a point when the output of first stage down phase capture unit 315 is already active. As a result, second stage down phase capture unit 325 may capture negative phase differences down to −540°. Resetting control blocks 335 control the reset sequence of down phase capture units 315 and 325 to ensure that all phase values in the negative phase range are captured. Down sum unit 340 combines the outputs from down phase capture unit 315 and 325 to produce down signal 215 , which represents the input phase difference in a negative direction.
A similar interaction occurs between the first stage up phase capture unit 320 , second stage up phase capture unit 330 and resetting control blocks 335 . The output of first stage up phase capture unit 320 goes active when it detects an input A 20 rising edge. This allows first stage up phase capture unit 320 to capture positive phase differences up to +360°. First stage up phase capture unit 320 is connected to a second stage up phase capture unit 330 . The output of second stage up phase capture unit 330 may go active when a second input A 20 rising edge is detected at a point where the output of the first stage unit 320 is already active from the detection of the first rising edge. This allows PFD 10 to capture phase differences up to +540°. Up sum 345 combines the outputs of units 320 and 330 to produce up signal 220 , which represents the input phase difference in a positive direction.
FIGS. 2A and 2B show another exemplary embodiment of the PFD of the present disclosure, indicated generally at 10 . The operation of PFD 10 may be illustrated by reference to the timing diagrams depicted in FIGS. 3-7, depicting various gradually increasing phase offsets in one direction (e.g., the input A 20 rising edge occurs first). The design of PFD 10 is symmetrical in that the response to the phase offsets in the opposite direction is substantially identical, but uses flip flops 30 , 35 , 80 and 65 (D 1 , D 2 , DR 2 and DOWN_s, respectively), shown in FIG. 2A, instead of flip flops 150 , 155 , 130 , and 180 (U 1 , U 2 , UR 2 and UP_s, respectively), shown in FIG. 2 B. It should be noted that the exemplary embodiment of PFD 10 shown in FIGS. 2A and 2B is one example of implementing the required PFD functionality. One of ordinary skill in the pertinent arts will recognize that other types of gates and gate arrangements may be used to provide an equivalent functionality.
DFF units 30 (D 1 ) and 150 (U 1 ) allow PFD 10 to phase capture input phase difference of up to ±360°. DFF units 35 (D 2 ) and 155 (U 2 ) extend the phase capture range up to ±540°. PFD 10 also includes resetting control blocks to control the reset of these DFF units. Units 90 , 95 and 100 serve as resetting control blocks to control the resetting of DFF 30 (D 1 ) with signal resetd 1 . The resetting of DFF 150 (U 1 ) is controlled by units 110 , 100 and 95 with signal resetu 1 . Units 105 , 80 and 75 control the resetting of DFF 35 (D 2 ) with signal resetd 2 . Units 115 , 130 and 140 control the resetting of DFF 155 (U 2 ) with signal resetu 2 .
PFD 10 includes components to sum outputs from selected components to produce a final output signal. Block 60 combines the outputs from DFF blocks 30 and 35 (D 1 and D 2 ) to produce the final output signal Down 215 . In the exemplary embodiment shown in FIG. 2A, block 60 may be an OR logical component. The output signal Down 215 represents the input phase difference, in a negative direction. Output signal Down 215 may be a pulse width varying signal. The negative direction indicates that the input B 15 rising edge occurs before the input A 20 rising edge.
Block 145 combines the outputs from DFF blocks 150 and 155 (U 1 and U 2 ) to produce the final output signal Up 220 . In the exemplary embodiment shown in FIG. 2B, block 145 may be an OR logical component. The output signal Up 220 represents the input phase difference, in a positive direction. Output signal Up 220 may be a pulse width varying signal. Generally, the positive direction indicates that the input A 20 rising edge occurs before the input B 15 rising edge.
In order to provide the extended range of PFD 10 , the output and resetting of the DFF components must be properly timed or sequenced. The sequencing of outputs from DFF units 30 , 35 and 80 (D 1 , D 2 and DR 2 , respectively), shown in FIG. 2 A,provide for the extended range of PFD 10 for negative phase differences. The extended range is made possible by the output of DFF 35 (D 2 ) going high, i.e., qpfdD 2 =1, in response to a second B input 15 rising edge, when the output of DFF 30 (D 1 ), signal qpfdD 1 , is already high from the first B input 15 rising edge. The output signal for DFF 35 (D 2 ), qpfdD 2 , goes high because the phase difference is less than −360°. As a result, PFD 10 may keep track of the 0° position past −360°.
In order to prevent the output signal from DFF 30 (D 1 ) from being overlooked, components 40 , 45 , 50 and 55 , shown in FIG. 2A, are used to provide a delay that is longer than the reset time for DFF 30 (D 1 ). For example, the function of the delay components may be observed in the situation where an input A 20 rising edge closely follows an input B 15 rising edge. First, the output signal qpfdD 1 from DFF 30 (D 1 ) goes high in response to the input B 15 rising edge. Next, the output signal qpfdU 1 from DFF 150 (U 1 ) goes high in response to the input A 20 rising edge. This sequence triggers reset signal resetd 1 to go low to reset DFF 30 (D 1 ). If DFF 30 (D 1 ) is reset too soon, then the output signal qpfdD 1 from DFF 30 (D 1 ) will not be captured by DFF 35 (D 2 ) and, as a result, the fact that there was an input B 15 rising edge would be lost. Accordingly, the delay introduced by components 40 , 45 , 50 and 55 provides that qpfdD 1 is high for long enough that a high signal (signal d_d 2 ) may be read into the D input of DFF 35 (D 2 ) before signal qpfdD 1 goes low in response to reset signal resetd 1 .
In order to ensure that all phase values are being recorded, PFD 10 provides for a specific reset sequence of both DFF 30 (D 1 ) and DFF 35 (D 2 ). For example, DFF 80 (DR 2 ) resets DFF 35 (D 2 ) on the falling edge of the input B 15 signal when both qpfdD 1 and qpfdD 2 are both high. This interaction results in a phase capture range that extends to −540°. Gate 90 (I 8 ) ensures that DFF 30 (D 1 ) is not reset when the output signal qpfdD 2 of DFF 35 (D 2 ) is high. In order to move back from −370° to −350°, DFF 35 (D 2 ) must be reset and not set again before DFF 30 (D 1 ) is reset. Both of these mechanisms ensure that the range from −540° to −350° is not overlooked.
A similar sequence of events occurs for DFF units 150 , 155 , and 145 (U 1 , U 2 and UR 2 ), shown in FIG. 2 B. The extended range for positive phase differences is made possible by the output of DFF 155 (U 2 ) going high, i.e., qpfdU 2 =1, in response to a second A input 20 rising edge, when the output of DFF 150 (U 1 ), signal qpdfU 1 , is already high from the first A input 20 rising edge signal. The high status of qpfdU 2 in this case indicates that the phase difference has exceeded +360°. Accordingly, PFD 10 may keep track of the 0° position at phase differences of over +360°.
For the situation in which an input B 15 rising edge closely follows an input A 20 rising edge (the reverse of the scenario described above), components 160 , 165 , 170 and 175 provide a sufficient delay to ensure that signal qpfdU 1 , the output signal from DFF 150 (U 1 ), is high for long enough so that a high signal (signal d_u 2 ) may be read into the D input of DFF 155 (U 2 ) before signal qpfdU 1 goes low. As with DFF units 30 and 35 (D 1 and D 2 ), PFD 10 provides a specific set of sequences for resetting DFF units 150 and 155 (U 1 and U 2 ) to ensure that phase values are not missed. For example, DFF 130 (UR 2 ) resets DFF 155 (U 2 ) on the falling edge of the A input when the outputs qpfdU 1 and qpfdU 2 , from DFF 150 (U 1 ) and 155 (U 2 ), respectively, are both high. This provides for the +540° phase range limit. Gate 110 (I 11 ) ensures that DFF 150 (U 1 ) is not reset when the output of DFF 155 (U 2 ) signal qpfdU 2 is high. In moving from 350° to 370°, DFF 155 (U 2 ) is reset and not set again until DFF 150 (U 1 ) is reset. Accordingly, the phase value from 350° to 540° is not overlooked.
FIGS. 3-7 show timing diagrams of an exemplary embodiment of the present invention. In FIG. 7, the phase offset between input A and input B starts at 90° and increases to 540°. When the phase position returns to 0°, the up and down pulses are balanced. Accordingly, the system 10 is able to remember the 0° phase position even for a phase offset of 540°. As a result, the system 10 has a capture range of ±540°. FIGS. 3-6 show the operation of PFD 10 at a +90°, +270°, +450° and +540° input phase difference, respectively. As shown in FIGS. 4-6, at phase offsets of over 360° the final “up” and “down” signals show that the “up” signal is continuously on during this time. This particular embodiment of PFD system 10 provides a proportional pulse width modulated phase measurement up to 360°.
In another exemplary embodiment of PFD 10 , the circuit may include output sampling DFF units 180 (UP_s) and 65 (DOWN_s). DFF units 10 (Up_s) and 65 (DOWN_s) sample Up signal 220 and Down signal 215 , respectively, in accordance with clock signal 205 , to produce Up_sync signal 185 and Down_sync signal 70 , respectively. These DFF units 180 and 65 are used for sampling into a digital system and are not necessarily required in an APLL (analog PLL) system. In another exemplary embodiment, PFD 10 may accept preconditioning signals 210 (preconU_b) and 25 (preconD_b) from a digital coarse phase detector (not shown in FIGS. 2 A and 2 B). The operation of the preconditioning signals is discussed below in connection with FIG. 8 . PFD 10 may also have optional enabling signals engaging a ±180°, ±360° or ±540° locking range. For example, in an exemplary embodiment of PFD 10 , the circuit includes signal 120 (enable_ 180 ) to enable the phase range of ±180°. Similarly, PFD 10 may include signal 125 (disable_ 540 ) to disable the extended ±540° locking range.
PFD 10 may be implemented in a phase detection system with other types of phase detectors. FIG. 8 shows an exemplary embodiment of a phase detection system, shown generally at 280 . Phase detection system 280 includes PFD 10 and a coarse digital phase detector. In this particular embodiment, the coarse digital phase detector is an up/down digital counter that may be used to measure complete cycle slips. The digital counter may be based on any suitable numbering scheme or concept. Generally, a digital counter can count cycles but does not track the location of a 0° position as well as a fine phase detector such as, for example, PFD 10 . Accordingly, phase detection system 10 combines the digital counter's ability to track cycle slips with the ability of PFD 10 to track and lock in to a 0° position. Because PFD 10 and the coarse phase detector provide an overlap in response, there is substantially no dead-band in the transition between the two phase detectors.
Phase detection system includes edge detect components 240 and 245 . The rising edge of input clock signal B 15 and input clock signal A 20 is detected by input B edge detect 240 and input A edge detect 245 , respectively. The outputs of edge detect 240 and 245 are connected to count control 250 . Count control 250 is connected to counter 255 . Count control 250 handles the decision to increment, decrement or make no change to counter 255 . Counter 255 increments when the rising edge of input A 20 is detected. Counter 255 decrements when the rising edge of input B 15 is detected. When both are detected at the same time, no counter change is made. Counter 255 is associated with a programmable limit set 270 . Limit set 270 defines the maximum and minimum counter value. This maximum and minimum counter value corresponds to the required phase capture range. For example, with a maximum counter value of 8191, the phase capture range of the whole system would be 8191×360°=2,948,760°.
Generally, counter 255 will produce +1, −1 or 0 count values when the A and B input edges are close to each other. If the distance between the edges exceeds a defined phase difference, then counter 255 may increment or decrement by larger count values. For example, at +360° phase offset, the counter may produce +2, 0 or +1 count values. The coarse phase detector value may be used when the count value is greater than +1 or less than −1.
Counter 255 is connected to output control 260 . Output control 260 handles the decision of whether to use the coarse phase detector value. If output control 260 decides to use the coarse phase detector value from counter 255 , then this value will be sent to digital filter 265 . Digital filter 265 averages the count value along with the up and down output signals from PFD 10 . Accordingly, the output of digital filter 265 is a representation of the input phase. Digital filter 265 averages the PWM (pulse width modulated) signals of Up_sync 185 and Down_sync 70 from PFD 10 in addition to the different count values from counter 255 . The count values are also effectively PWM signals because, for example, the +2 and +3 values would provide greater precision after averaging and resolving down to fractions of a period. For instance, in a stream of 100 counter values, with 35 values of +2 and 65 values of +3, the measured phase value from the averaging digital filter 265 would be +2.35. Note that in this exemplary embodiment, the sampled signals 185 and 70 are used because PFD 10 is connected with a digital component, i.e., digital filter 265 .
Output control 260 may also send preconditioning signals 25 and 210 to PFD 10 . As discussed above, the preconditioning signals are used to ensure that PFD 10 and the coarse phase detector operate in a harmonious fashion. Without this link, the two phase detectors may pull in opposite directions. The manner in which PFD 10 is preconditioned by signals 210 (preconU_b) and 25 (preconD_b) is based on the counter value currently tallied by digital counter 255 . If the counter value is a positive, non-zero number, then there is a phase difference in the positive phase direction between the two input signals 15 and 20 . Accordingly, preconditioning signal 210 (preconU_b) should be asserted to indicate that to PFD 10 that there is a phase change in the positive phase direction. On the other hand, if the counter value is a negative number, then there is a phase difference in the negative direction. As a result, preconditioning signal 25 (preconD_b) should be asserted to indicate to PFD 10 that there is a phase change in the negative phase direction. In one exemplary embodiment, PFD 10 is preconditioned according to the logical description shown in Table I based on the exemplary embodiment of PFD 10 shown in FIGS. 2A and 2B (e.g., the preconditioning signals are active low).
TABLE I
Counter
PreconD_b
preconU_b
<−1
goes to 0
goes to 1
>1
goes to 1
goes to 0
0, 1 or −1
goes to 1
goes to 1
The application of the preconditioning signals ensures a smooth continuation of phase measurement across the 360° boundary and maintains the memory of the 0° phase position.
In the exemplary embodiment shown in FIG. 8, PFD 10 , Edge detects 240 and 245 , counter 255 , output control 260 and digital filter 265 are all clocked components. The resolution of the system is determined by the system clock rate that drives all of the digital blocks and whether the system clock is synchronized with the main clock.
FIG. 9 depicts a phase sweep showing a range from 0 UI to +2.5 UI (+900°) and back to 0 U 1 . The simulation waveform illustrates the interaction of the components of the system shown in FIG. 8 to track a varying input phase difference. With preconditioning from digital phase counter 255 , the system can keep track of many cycles. As shown in FIG. 9, the system goes to +2.5 UI and then completely recovers to the same position back at 0 UI (0°). The counter value from counter 255 steps from 0 to −3 and back to 0 again. The digital count value is represented by an analog waveform. When the count value is less than −1, then signal 25 (preconD_b) activates, e.g., active low, which preconditions DFF 35 (D 2 ) and output qpfdD 2 to go high. This high signal notifies PFD 10 that digital counter 255 is indicating that the phase is at least less than −360°. Accordingly, FIG. 9 shows that phase detection system 280 remembers the 0° position and is able to return to this position rather than lock one or more cycles away.
Having thus described a preferred embodiment of the phase detection system, it should be apparent to those skilled in the art that certain advantages of the described method and system have been achieved. It should also be appreciated that various modifications, adaptations, and alternative embodiments thereof may be made within the scope and spirit of the present invention. For example, particular gates and gate arrangements have been illustrated, but it should be apparent that the inventive concepts described above would be equally applicable to alternate gates and gate arrangements that provide equivalent functionality. The invention is further defined by the following claims. | A phase detection system allows the capture range, lock range and jitter tolerance to be extended beyond ±360°. The capture range for the phase detection system may be extended in programmable amounts up to several thousand clock cycles or can be set to any desired maximum capture range in steps of approximately 360°. The phase detection system circuit utilizes a coarse phase detector and a fine phase detector. The phase detection system uses the digital cycle slip counter phase detector to provide a wide phase capture and lock range for a large jitter tolerance. The phase detection system combines this detector with a fine phase measurement from a PFD (phase and frequency detector) for very accurate phase control and low output jitter. The PFD operates in the approximately ±540° range and provides overlap in response with a coarse phase detector using a digital cycle counter approach. The PFD allows the digital counter, used for coarse cycle slip tracking, to precondition the PFD so that the coarse and fine detectors work together with no dead-band and no conflict in responses. | 7 |
FIELD OF THE INVENTION
[0001] The present invention relates to a self-propelled road milling machine with a cooling system, where the cooling system comprises at least one fan for drawing in air, at least one cooler, and at least one suction channel that has a vent opening and an intake opening facing the cooler.
BACKGROUND ART
[0002] Current self-propelled road milling machines generally have a drive motor for propelling the road milling machine and for moving the tools.
[0003] For cooling the drive motor and the hydraulic liquid, current road milling machines have a cooling system, which usually consists of a fan for drawing in ambient air, a cooler, and a suction channel. The suction channel, which is usually formed by parts of the chassis, has an intake opening that is directed either to the rear—that is, in the direction counter to the machine's direction of travel—or to the front—that is, in the machine's direction of travel. Accordingly, the ambient air is drawn in either from the rear or the front. The suction channel runs from the intake opening along the longitudinal axis of the road milling machine to a vent opening located directly in front of the cooler. In order to prevent debris, e.g., small particles of milled material or construction waste, from getting into the cooler, a gratelike cooler grill is located in front of the suction channel's intake opening.
[0004] The cooler itself has several ducts around which ambient air may circulate. They are located in front of the vent opening, and a coolant for the drive motor is flowing through them. A fan is provided either in front of or behind the cooler, as seen from the direction the air is flowing, in order to draw in the ambient air. In this context the so-called combination coolers should be mentioned in which several separate cooling circuits are provided, e.g., a cooling circuit for the drive motor coolant—as described above—a cooling circuit for hydraulic fluid, and, if necessary, an additional cooling circuit, e.g., for charge air. All of these are configured on the same principle.
[0005] Current road milling machines, which have suction channels directed either to the front or the rear, have the disadvantage that despite the cooler grill a great amount of dust and dirt can enter the suction channel and eventually reach the cooler and the fan. Furthermore, it is also disadvantageous that the cooling system described generates a great amount of noise.
SUMMARY OF THE INVENTION
[0006] The purpose of the present invention is to produce a self-propelled road milling machine, in which the cooling system and the components surrounding it are less prone to becoming dirty and generate less noise.
[0007] The cooling system of the self-propelled road milling machine according to the invention has at least one fan for drawing in cooling air from the ambient air. A self-propelled road milling machine in this context refers to a machine that is equipped with its own drive motor for propulsion. The fan can be any device that allows the drawing-in of air; normally, rotating fan blades are used. Further, the cooling system includes at least one cooler. The cooler can, for example, be structured as initially described according to the current state of the art. Furthermore, the cooling system is comprised of at least one suction channel with a vent opening facing the cooler and an intake opening. According to the invention, in relation to the machine's longitudinal axis, the intake opening is pointed to the side of the milling machine, so that the cooling air can be drawn in from the side. The longitudinal axis refers to the axis of the road milling machine that extends along the length of the machine from the rear to the front.
[0008] The suction channel and the components attached to the suction channel are significantly less subject to accumulating dirt when the air is drawn in from the side, in particular, because a great amount of dust is stirred up in front of or behind the road milling machine. Furthermore, it has been demonstrated that the noise generated by the cooling system can be reduced by placing the intake opening on the side of the machine. This is due to the fact that the suction channel with the lateral air supply can be longer than when the air flows into it directly from the front.
[0009] In one preferred embodiment of the road milling machine according to the invention, the suction channel has at least three sections. One channel section is connected to the intake opening and is positioned in such a way that the air basically flows parallel to the longitudinal axis of the road milling machine. A second channel section connected to the first one is designed in such a way that the air basically flows diagonally to the longitudinal axis. The third channel section is connected to the second one and is designed in such a way that the air basically flows parallel to the longitudinal axis all the way to the vent opening. Preferably, the channel sections and the junctions between them are designed in such a way that as little turbulence as possible is generated. The special, relatively long design of the suction channel with the separate channel sections results in less noise generation.
[0010] Since the cooling system is positioned on the front end of many road milling machines, in a preferred embodiment of the invention the channel sections are positioned in such a way that the air in the first channel section basically flows in the direction counter to the machine's direction of travel. In the second channel section, the air essentially flows across the machine's direction of travel, and in the third channel section it essentially flows in the direction counter to the machine's direction of travel all the way to the vent opening.
[0011] An especially preferred embodiment of the road milling machine, according to the invention, is designed to achieve a particularly effective air supply to the cooling system by providing two suction channels. Here, the intake opening of the first suction channel is on one side, and the intake opening of the second suction channel on the opposite side of the road milling machine. In order to achieve an equal suction of air through both suction channels, the fan can be comprised either of two ventilators or one large fan of sufficient capacity for supplying both suction channels equally. The suction channels can be run separately or lead to a common vent channel.
[0012] In many cases, road milling machines are equipped with a tank for a fluid; this tank is usually filled with water. In an especially preferred embodiment, the suction channel is constructed inside the tank. The liquid-filled tank has a sound-deadening or sound-absorbing effect on the suction channel so that the noise generated by the cooling system is further reduced.
[0013] In another especially preferred embodiment, the suction channel is built of one piece with the tank. Thus, the liquid tank and suction system form a modular unit that can easily be installed on the chassis of the road milling machine.
[0014] The tank is preferably made of plastic so that it and (when applicable) the suction channel are as weatherproof as possible. Furthermore, plastic has high impact resistance; this is very important considering the working environment of road milling machines because it prevents damage from milled material thrown up by the machine.
[0015] In another preferred embodiment, the suction channel is concealed by a removable plate on the side in relation to longitudinal axis of the road milling machine.
[0016] In another preferred embodiment, the intake opening is located in this plate. Thus, the intake opening can consist, for example, of several holes placed next to each other inside the plate so that a cooler grill or similar device is not necessary.
[0017] In another advantageous embodiment, the plate is equipped with a sound-absorbing mat, which further reduces the noise generated by the cooling system. This can be positioned, for example, on the inside of the plate facing the suction channel and can extend over the area of the plate that surrounds the intake opening.
[0018] In another preferred embodiment, the cooler and the fan are attached to the liquid tank. This enables a simple, modular connection of the complete cooling system, including the tank, to the other components of the road milling machine.
[0019] In order to cool the hydraulic fluid as well as the coolant for the road milling machine's drive motor, the cooler is designed in a preferred embodiment as a so-called combination cooler. That is, the cooler has, for example, one cooling circuit for the drive motor coolant, one cooling circuit for the hydraulic fluid, and, if necessary, another cooling circuit for charge air.
[0020] The road milling machine can be designed as a rear-loading road milling machine, where the milled material is discharged from the rear of the milling machine and perhaps transferred to an accompanying vehicle. For this type of machine, the liquid tank, together with the cooling system, can be placed especially advantageously on the front of the machine. Of course, road milling machines can also be front loaders.
[0021] In many cases, the liquid tank on a road milling machines is located on the front end of the vehicle with the front wheels or front wheel located underneath the tank. Therefore, it is not possible for the operator in the driver's cab to see the position and orientation of the front wheel. Especially during the machine's approach to the site, this can pose risks to other personnel around the machine and also to the machine itself. In a preferred embodiment, the liquid tank is located above a steerable wheel or the steerable wheel axle. A channel extends through the liquid container and carries a means of transmission that transmits the orientation of the wheel or the wheel axle to a direction indicator on the top of the liquid tank. The means of transmission can be a transmission shaft, for example, and the direction indicator can be a rotatable needle.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] In what follows, the invention is explained in detail using examples of embodiments and referring to the enclosed figures, as follows:
[0023] FIG. 1 : A schematic illustration of one embodiment of the road milling machine according to the invention in form of a rear-loading road milling machine; lateral view.
[0024] FIG. 2 : A section along line A-A of FIG. 1 .
[0025] FIG. 3 : A top view in the direction of the arrow B of FIG. 1 .
[0026] FIG. 4 : A top view of a liquid tank according to another embodiment of the present invention.
[0027] FIG. 5 : A lateral view of the liquid tank in FIG. 4 in the direction of the arrow C, with the plate removed.
[0028] FIG. 6 : A lateral view of the plate not shown in FIG. 5 .
[0029] FIG. 7 : A section along the line D-D of FIG. 4 .
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0030] FIG. 1 shows a rear-loading road milling machine ( 2 ). The road milling machine ( 2 ) has a chassis ( 4 ), which is supported in the present embodiment by three wheels ( 6 , 6 , 8 ), where both the rear wheels ( 6 , 6 ) (only one of them can be seen in FIG. 1 ) are located on the sides at the rear. The front wheel ( 8 ) is located in the center of the front end of the road milling machine ( 2 ). The height of the rear wheels ( 6 , 6 ) can be adjusted using hydraulics, and the road milling machine ( 2 ) is steered via the front wheel ( 8 ), which can be rotated around a vertical axis (a). Alternatively, this kind of road milling machine ( 2 ) can also be supported on tracks instead of the wheels ( 6 , 6 , 8 ). The number of wheels or tracks can vary.
[0031] In addition, at least one drive motor for a rotary cutter and the wheels ( 6 , 6 , 8 ) and a hydraulic system are provided inside the chassis ( 4 ). Furthermore, the additional state-of-the-art drive systems are provided, but they are not shown in the drawings for reasons of clarity.
[0032] The driver's cab ( 10 ) is provided on the top at the rear of the road milling machine ( 2 ), where, among other things, there is a seat ( 12 ) for the operator and steering gear ( 14 ) for steering the front wheel ( 8 ).
[0033] The cutter housing ( 16 ) is positioned below the driver's cab ( 10 ). The cutter housing ( 16 ) is open at the bottom toward the tarmac ( 18 ). This housing contains a rotary cutter ( 20 ) whose longitudinal axis extends at right angles to the direction of travel, which is indicated in FIG. 1 by the arrow (b). The rotary cutter ( 20 ) protrudes downward beyond the cutter housing ( 16 ) toward the tarmac ( 18 ).
[0034] A height-adjustable scraper unit ( 22 ) is provided at the rear end of the cutter housing ( 16 ), as seen from the direction of travel (b). Another transport unit ( 24 ) is provided behind the scraper unit ( 22 ), as seen from the direction of travel (b). This transport unit may be used to transfer the milled material to an accompanying truck with an appropriate loading area (not shown). Since the milled material is transferred to the truck from the rear end of the road milling machine, the machine is a rear-loading road milling machine, as mentioned above.
[0035] The road milling machine ( 2 ) has a rear ( 26 ) and a front end ( 28 ), where the front end ( 28 ) points forward in the direction of travel (b) and the rear ( 26 ) points in the opposite direction. In what follows, the longitudinal axis ( 30 ) referred to is that axis of the road milling machine ( 2 ) that extends in longitudinal direction of the road milling machine ( 2 ) from the rear ( 26 ) to the front end ( 28 ).
[0036] A liquid tank ( 32 ) is positioned on the front end ( 28 ) above the front wheel ( 8 ); this tank is usually filled with water. There is a cooler ( 34 ) positioned behind the liquid tank ( 32 ), as seen from the direction of travel, and it is attached to this tank ( 32 ). Attached to the cooler ( 34 ), there is a fan ( 36 ), which is used to draw in air.
[0037] With reference to FIG. 2 , the cooling system of the road milling machine ( 2 ) according to the invention is described as follows: In addition to the above-described cooler ( 34 ) and fan ( 36 ), the cooling system consists of two suction channels ( 38 and 40 ). The suction channels ( 38 , 40 ) each have a vent opening ( 42 or 44 ) facing the cooler ( 34 ) and an intake opening ( 46 , 48 ). The intake opening ( 46 ) of the suction channel ( 38 ) points to one side in relation to the longitudinal axis ( 30 ) of the road milling machine ( 2 ); as seen from machine's direction of travel (b), it points to the left. The intake opening ( 48 ) of the suction channel ( 40 ) points to the other side in relation to the longitudinal axis ( 30 ) of the road milling machine ( 2 ); as seen from the machine's direction of travel (b), it points to the right. When the fan ( 36 ) is operating, it is therefore possible for both suction channels ( 38 , 40 ) to draw in the cooling air from the side as indicated by the arrows (c, c).
[0038] The suction channels ( 38 or 40 , respectively) have a first channel section ( 50 or 52 ) that is positioned in the direction of flow behind the intake openings ( 46 or 48 , respectively). The first channel section ( 50 or 52 ) is designed in such a way that the air drawn in basically flows parallel to the longitudinal axis ( 30 ) and counter to the direction of travel as indicated by the arrows (d, d).
[0039] A second channel section ( 54 or 56 ) pointing to the inside is connected to the first channel section ( 50 or 52 , respectively) so that the air basically flows at right angles to the longitudinal axis ( 30 ), as indicated by the arrows (e, e). In the embodiment shown, both air streams are conducted through the second channel section ( 54 or 56 ) toward the center of the vehicle, so that the two streams approach each other before they are conducted to the cooler ( 34 ), as described in what follows.
[0040] Finally, the suction channels ( 38 ; 40 ) each have a third channel section ( 58 or 60 respectively) through which the air again flows parallel to the longitudinal axis ( 30 ) and counter to the direction of travel (b) toward the corresponding vent opening ( 42 ; 44 ), where the air reaches the cooler ( 34 ). In contrast to the embodiment illustrated, it is also possible to combine the two sections ( 58 ; 60 ) into one.
[0041] As shown in FIG. 2 , the suction channels ( 38 ; 40 ) are positioned inside the liquid tank ( 32 ) so that they are, for the most part, surrounded by the fluid ( 96 ) contained in the tank ( 32 ). Furthermore, the suction channels ( 38 ; 40 ) are constructed as one piece together with the plastic liquid tank ( 32 ). The suction channels are positioned in the liquid tank in such a way that the air flows for the most part without turbulence. This is achieved by using curved walls largely without edges and corners.
[0042] The channel sections ( 50 ; 52 ) of the suction channels ( 38 ; 40 ) are covered on the side by a removable plate ( 62 or 64 ). On the front end, as seen in the direction of travel (b), of the plate ( 62 or 64 ), there is an opening that corresponds to the intake opening ( 46 ; 48 ) described above. A latticelike structure ( 66 or 68 ) (see also FIG. 1 and FIG. 6 ) is provided inside the intake openings ( 46 ; 48 ) to prevent large particles of debris from getting into the machine.
[0043] The plates ( 62 ; 64 ) are both equipped with a sound-absorbing mat ( 70 ; 72 ) facing the suction channel ( 38 ; 40 ) to dampen noise generated by the cooling system. The dimensions of the sound-absorbing mats ( 70 ; 72 ) are designed in such a way that in the lateral view the mats cover the second channel section ( 54 ; 56 ).
[0044] The cooler ( 34 ) is designed as a so-called combination cooler. That is, it consists of one cooling circuit for the drive motor coolant and a second cooling circuit for the hydraulic fluid of the hydraulic system. The coolant for the drive motor is conducted to the cooler via the conduit ( 74 ), and after cooling it is returned to the drive motor via another conduit ( 76 ). In addition, the hydraulic fluid for the hydraulic system is conducted to the cooler ( 34 ) via a conduit ( 78 ), and after cooling it is returned to the hydraulic system via another conduit ( 80 ). The cooler ( 34 ) itself is of a state-of-the-art design.
[0045] As mentioned above, the liquid tank ( 32 ) is positioned above the front wheel ( 8 ). Furthermore, the front wheel ( 8 ) is located in the center in relation to the chassis ( 4 ) so that the operator cannot see the orientation of the front wheel ( 8 ). This can cause problems, especially during the machine's approach to the work site. In order to overcome this disadvantage, the liquid tank ( 32 ) has a direction indicator ( 82 ) in the form of a needle (see also FIG. 3 ). This needle can be rotated and is connected to the front wheel ( 8 ) via a means of transmission (not embodied here), e.g., a shaft, in such a way that it displays the orientation of the front wheel ( 8 ). In order to keep the transmission path as short as possible, a further channel ( 84 ) is provided inside the liquid tank ( 32 ). This channel is constructed in one piece with the tank. This channel carries a means of transmission and extends from the front wheel ( 8 ) or its suspension up to the direction indicator ( 82 ) to transmit the orientation of the front wheel to the needle-shaped direction indicator ( 82 ).
[0046] In FIGS. 4 through 7 , another liquid tank ( 32 ′) according to one embodiment of the road milling machine according to the invention is shown. This tank corresponds to the liquid tank ( 32 ) described above, so that only the differences are described in what follows. Similar or identical parts are marked with the same reference numbers.
[0047] On the top of the liquid tank ( 32 ′), there are two lateral openings that are closed using a lid ( 86 , 86 ). The tank can be filled with liquid through these openings ( 86 , 86 ), and their lateral arrangement simplifies the filling from both the right and the left side of the road milling machine ( 2 ). In addition, the liquid tank ( 32 ′) has a drain opening positioned at the lowest point of its floor; this opening is closed with another lid ( 88 ).
[0048] Furthermore, the liquid tank ( 32 ′) is equipped with a transparent fill level indicator ( 90 ) in the form of a pipe or hose on one or on both sides to allow the fill level to be read. When assembled, the plate ( 64 ) is placed over the fill level indicator ( 90 ). Oblong notches ( 92 ) are provided so that the column of liquid can be read. The bars ( 94 ) between the successive notches ( 92 ) are used for calibration. | A self-propelled road milling machine is equipped with a cooling system comprising a fan for drawing in air, a cooler, and a suction channel. The suction channel has a vent opening facing the cooler and an intake opening. In relation to the longitudinal axis of the road milling machine, the intake opening points to the side of the road milling machine, so that air is drawn in from the side. This results in significantly less dirt being sucked into the machine than when the suction channel is positioned in the direction of travel. In a preferred embodiment, the suction channel is formed in one piece with a liquid tank of the road milling machine. The liquid tank and suction system therefore form a modular unit, which can be easily installed on the chassis of the road milling machine. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Application Nos. 60/666,839 and 60/666,840, both filed 31 Mar. 2005, and U.S. Provisional Application Nos. 60/667,287, 60/667,312, 60/667,313, 60/667,375, 60/667,443, and 60/667,458, collectively filed 1 Apr. 2005, the entire contents and substance of which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to communication networks and, more particularly, to architecture for a high-speed, high-frequency wireless system.
2. Description of Related Art
As the world becomes more reliant on electronic devices, and portable devices, the desire for faster and more convenient devices has increased. Accordingly, producers of such devices strive to create faster, easier to use, and more cost-effective devices to serve the needs of consumers.
Indeed, the demand for ultra-high data rate wireless communication has increased, in particular due to the emergence of many new multimedia applications. Due to some limitations in these high data rates, the need for ultra-high speed personal area networking (PAN) and point-to-point or point-to-multipoint data links becomes vital.
Conventional wireless local area networks (WLAN), e.g., 802.11a, 802.11b, and 802.11g standards, are limited, in the best case, to a data rate of only 54 Mb/s. Other high speed wireless communications, such as ultra wide band (UWB) and multiple-input/multiple-output (MIMO) systems can extend the data rate to approximately 100 Mb/s.
To push through the gigabit per second (Gb/s) spectrum, either spectrum efficiency or the available bandwidth must be increased. Consequently, recent development of technologies and systems operating at the millimeter-wave (MMW) frequencies increases with this demand for more speed.
Fortunately, governments have made available several GHz (gigahertz) bandwidth unlicensed Instrumentation, Scientific, and Medical (ISM) bands in the 60 GHz spectrum. For instance, the United States, through its Federal Communications Commission (FCC), allocated 59-64 GHz for unlicensed applications in the United States. Likewise, Japan allocated 59-66 GHz for high speed data communications. Also, Europe allocated 59-62, 62-63, and 65-66 GHz for mobile broadband and WLAN communications. The availability of frequencies in this spectrum presents an opportunity for ultra-high speed short-range wireless communications.
Converting a signal from analog to digital at such high frequencies and at such high speeds is currently not cost effective. Also, line of sight is required to transmit at such frequencies and speed, so an obstruction in the wireless communication can slow, or even stop, transmission of communication.
What is needed, therefore, is an assembly for ultra-high frequencies (approximately 60 GHz) and ultra-high speeds (approximately 10 Gb/s) to convert from an analog signal to a digital signal that is low cost. Furthermore, a device adapted to operate when an obstruction, or severe shadowing, occurs is needed. It is to such a device that the present invention is primarily detected.
BRIEF SUMMARY OF THE INVENTION
The present invention is a receiver assembly. The receiver assembly comprises an N-array antenna assembly having a plurality of antennas, wherein the plurality of antennas are adapted to operate at a bandwidth of approximately 60 GHz; a plurality of amplifiers in communication with each antenna of the plurality of antennas of the N-array antenna assembly for amplifying a signal received by each antenna; a down converter for performing frequency conversion of a amplifier signal being emitted by each amplifier of the plurality of amplifiers; a demodulator adapted to recover data and recover clock signals; a latch for realigning clock signals, wherein the latch is based on a bit rate of a clock signal; a first-in/first-out circuit for organizing and recovering the clock signal; and a logic circuit for correlating known sequences to correct errors in the signal.
The logic circuit can emit a digital signal, wherein the receiver assembly receives the analog signal and converts the analog signal to the digital signal. The plurality of filters can be low noise amplifiers. The first-in/first out circuit can include serializer/deserializer (SERDES) architecture. The receiver assembly can further comprise a clocking device.
Each antenna of the plurality of antennas can provide approximately 10 dBi of gain, an azimuth 3 dB beam-width of approximately 60 degrees, and an elevation 3 dB beam-width in a range of approximately 30 to 35 degrees, which can produce an unexpected result at the preferred operating frequency.
Each antenna of the plurality of antennas can include a different orientation.
The N-array antenna assembly can provide a sectored coverage of approximately 60 degrees in an azimuth plane. The N-array antenna assembly can further provide a sectored coverage of approximately 180 degrees in an elevation plane.
The present invention also discloses a method. The method of converting an analog signal to a digital signal, wherein the analog signal has a bandwidth of approximately 60 GHz, the method comprising: receiving the analog signal operating at approximately 60 GHz with a plurality of antennas; feeding the analog signal received from the plurality of antennas to a filter; filtering the analog signal to create a cleaned signal; converting the frequency of the cleaned signal by down converting the cleaned signal; demodulating the signal; synchronizing the signal; and correlating the signal to known sequences.
Synchronizing the signal can include delaying the signal by delaying the signal with another signal.
These and other objects, features and advantages of the present invention will become more apparent upon reading the following specification in conjunction with the accompanying drawing figures.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a block diagram of a receiver assembly, in accordance with a preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
To facilitate an understanding of the principles and features of the invention, it is explained hereinafter with reference to its implementation in an illustrative embodiment. In particular, the invention is described in the context of being a wireless receiver assembly for operation at ultra-high frequencies and ultra-high data communication speeds.
The materials described as making up the various elements of the invention are intended to be illustrative and not restrictive. Many suitable materials that would perform the same or a similar function as the materials described herein are intended to be embraced within the scope of the invention. Such other materials not described herein can include, but are not limited to, for example, materials that are developed after the time of the development of the invention.
The present invention is a receiver assembly 100 . The receiver assembly 100 comprises an N-array antenna assembly 110 , a down converter 120 , a demodulator 130 , a latch 140 , a first-in/first-out circuit (FIFO) 150 , and logic 160 . The receiver assembly 100 obtains an analog signal from the air. The analog signal, as it is fed through the receive assembly 100 , is converted to a digital signal. Accomplishing this analog to digital conversion is not an easy task at high frequencies and high data speeds.
The present invention is implemented with the combination of three over-arching concepts—antenna diversity, selection diversity (SD), and maximum ration combining (MRC). The present invention, preferably, operates at approximately 60 GHz, i.e., 54 to 66 GHz, and at approximately 10 Gb/s.
The N-array antenna assembly 110 includes N (number) fan beam series array antenna 112 . That is, the N-array antenna assembly 110 includes a plurality of antennas 112 . As illustrated in FIG. 1 , there are 5 array antennas 112 ; one skilled in the art would recognize that many antennas 112 can be implemented. Each antenna 112 can be designed to provide approximately 10 dBi of gain, an azimuth (i.e., H-plane) of approximately 3 dB having a beam-width of approximately 60 degrees, and an elevation (i.e., E-plane) of approximately 3 dB having a beam-width of approximately 30 to 35 degrees, the combination of which can present unexpected results. Preferably, the selected N fan beam antennas 112 for the receiver assembly 100 are different from one another, wherein, for instance, the antennas 112 have different gain, radiation patterns, shapes, sizes, and other differing characteristics between the antennas 112 .
The antennas 112 can be designed, further, to have different elevation beam orientations. The association of the different N antennas 112 can cover approximately 60 degrees in the azimuth plane, and approximately 180 degrees in the elevation plane. For instance, the N-array antenna assembly 110 includes three (3) antennas 112 , the antennas 112 can cover approximately 180 in at least 2 planes. The antenna 112 can be designed to receive an analog signal 105 , preferably operating at approximately 60 GHz.
Due to the direction pointed, each antenna 112 is less sensitive to a multi-path effect. Additionally, due to different beam orientations of the antenna 112 , each antenna 112 can receive, preferably, a line of sight signal, or, alternatively, a reflected signal (for instance, from a wireless repeater). The arrangement of the antennas 112 , as well as the plurality of antennas 112 , of the N-array antenna assembly 110 can enable a variety of angles, wherein enabling the receiver assembly 100 to receive a number of different signals, or the same signal, at different strengths.
Each antenna 112 is connected to an amplifier 114 . Preferably, the amplifier 114 is a low noise amplifier (LNA). As a signal 115 from each antenna 112 is transmitted through the antenna 112 , the selection diversity concept can be applied to select antennas 112 that exhibit, or provide, the highest signal-to-noise ratio (SNR). That is, the selection diversity format enables the best signal to be calculated. The antenna 112 that provides the best signal has that signal secured, while weaker signals are eliminated.
The amplifier 114 can emit a signal 117 . The signal 117 emitted from the amplifier 114 can then be fed into a down converter 120 . The down converter 120 can be adapted to perform frequency conversion to a lower frequency band.
The down converter 120 can emit a signal 125 . The signal 125 emitted from the down converter 120 is, preferably, fed next into a demodulator 130 . The demodulator 130 can convert the signal 125 from the down converter 120 to a baseband signal. Indeed, the demodulator 130 is adapted to recover the signal 125 and further recover data from the signal 125 , thus improving the signal 125 , by preferred analog techniques.
In a preferred embodiment, the demodulator 130 includes clock-recovery technology 132 and data-recovery technology 134 . The clock-recovery 132 and data-recovery 134 are applied to the signal 125 emitting from the down converter 120 . The application of the clock-recovery 132 and data-recovery 134 can create streams of bits that can be synchronized with latch functionality.
These streams of bits, or signal 135 , are inserted next into a latch 140 . The latch 140 can realign the signal 135 , which is dependent on the bit rate. A delay in the signal patch can be realigned in the latch 140 . The latch 140 can take the signal 135 and hold it for a predetermined time in order to align it from another signal 137 from the demodulator 130 , which can be received and fed from a different antenna through the receiver assembly, but can lag (time) a little behind the signal 135 . The realignment is also dependent on the bit rate.
These streams of bits, collectively signal 145 , are fed into the FIFO (first-in/first-out) 150 . The FIFO 150 can use SERDES (serializer/deserializer) architecture. The SERDES can covert the signal 145 from/to a serial data stream and a parallel data stream.
The signal 155 from the FIFO 150 can be then fed into a logic circuit 160 . The logic 160 can include coding to correlate known sequences of bits. The logic 160 can, preferably, include error detection 162 and error correction algorithms 164 . Specifically, error detection 162 coding within the logic 160 can correlate streams of data. Moreover, a maximum ratio, which can combine and take different input signals to correlate and assign weights, or preferences, of the signals. An analog signal to noise ratio 166 can be used to enables determining the weight of the signal.
The signal 165 emitted from the logic 160 is a digital signal. The analog signal 105 received by one or more antennas, as the signal runs through the receiver assembly, is converted to a digital signal.
While the invention has been disclosed in its preferred forms, it will be apparent to those skilled in the art that many modifications, additions, and deletions can be made therein without departing from the spirit and scope of the invention and its equivalents, as set forth in the following claims. | The present invention describes a receiver assembly for receiving an analog signal and converting the analog signal to a digital signal. The receiver assembly is, preferably, capable of receiving a signal operating at approximately 60 GHz. The receiver assembly includes a filter, a down converter, a demodulator, a latch, a FIFO, and a logic circuit. A method of converting the 60 GHz analog signal to a digital signal is also described. | 7 |
BACKGROUND OF THE INVENTION
This invention relates to an electrode assembly which is implantable in a human or animal body around a nerve. Typically, the electrode is connected by a wire or wires to an implanted electronic biostimulator which can be remotely programed, or by an electronic circuit commanded by an external wireless telemetry transmitter to deliver electrical signals to the nerve. The thus stimulated nerve in turn causes a reaction in one or more muscles to achieve a desired result, such as bladder control for a patient who has lost normal control due to injury or disease.
My U.S. Pat. No. 4,573,481 (the disclosure of which is incorporated herein by reference) describes in greater detail the various types of nerve-stimulating electrodes (e.g. cuff electrodes) which have been used in the past, and the problems which have been encountered with installation and use of these prior-art units. For brevity, the reader is referred to this patent for further background information.
The aforementioned patent discloses a spiral or helical electrode which solves many of the shortcomings of earlier designs, and is wound around the nerve of interest during surgical installation. Excellent results have been obtained with this electrode, but there are occasions where space around the nerve is limited, and the manipulation of the helix to wind it around the nerve demands skillful and painstaking care by the surgeon.
The electrode assembly (and associated installation tool) of the present invention incorporates the important advantages of my earlier helical design, and provides significant placement simplification and reduction of trauma risk during installation. Broadly, the new assembly is a flexible electrode-supporting matrix forming two oppositely directed helical portions extending from a central bridge or junction. Each helical portion extends circumferentially somewhat more than 360 degrees (typically about 420 to 540 degrees).
During installation, a tweezer-like tool has a pair of pins or tines which are fitted into the open central bore of the helical matrix. The tines are then expanded to distort and open the flexible helices so a laterally open passage is formed along the length of the matrix. The electrode assembly is then fitted over the nerve in a direction generally perpendicular to the length of the nerve. The tines are withdrawn to enable the matrix to close gently around the nerve to place one or more conductive electrodes in intimate contact with the nerve surface. Contrarotation of the several spiral or helical matrix portions provides a further advantage of improved electrode-assembly anchorage and resistance to unwanted movement along the nerve in response to movement of adjacent tissue or skeletal structure.
SUMMARY OF THE INVENTION
The invention is directed to a circumneural electrode assembly which includes a supportive flexible and insulating matrix formed into two oppositely directed helical portions which are centrally joined, and have free outer ends. The helical portions extend circumferentially at least one full turn, and preferably about one-half additional turn, for a total extent in the range of 360 degrees to 720 degrees. A thin and flexible conductive ribbon (preferably surface-roughened platinum) is secured to the inner surface of one of the helical portions, and multiple electrodes can be provided on one or both portions. A connecting wire or cable extends from the electrode and matrix for coupling to an electronic package which is normally implanted elsewhere in the patient's body.
The assembly is hollow, thus providing an open and generally cylindrical central passage throughout its longitudinal extent. A tweezer-like installation tool has a pair of separable pins or slender tines which are closed together for insertion in the central passage. Separation of the tines distorts the flexible matrix and electrode out of the helical shape into an open-sided configuration which permits the assembly to be slipped over the surgically exposed peripheral nerve in a direction generally perpendicular to the length of the nerve. With the assembly fitted over the nerve, the tool is withdrawn, and the assembly resiliently returns to the undistorted helical shape to encircle the nerve with the electrode in conductive contact with the nerve surface.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a pictorial view of a monopolar electrode assembly with closely spaced helical portions;
FIG. 2 is a view similar to FIG. 1, but showing a multipolar electrode assembly with more widely spaced helical portions;
FIG. 3 is a plan view of the electrode assembly of FIG. 2 as distorted into an unwound flat shape;
FIG. 4 is a view similar to FIG. 3, and showing the flattened configuration of the FIG. 1 assembly;
FIG. 5 is a pictorial view of an installation tool for the assembly;
FIG. 6 shows the installation tool fitted and expanded within the electrode assembly to open the helical portions which are positioned for placement over a nerve;
FIG. 7 shows the tool being removed after placement of the assembly around the nerve;
FIG. 8 is an end view of a portion of the assembly as expanded by the tool over the nerve; and
FIG. 9 is an enlarged section through one of the helical portions.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A first embodiment of an electrode assembly 10 according to the invention is shown in FIG. 1. The assembly includes a preformed resilient and insulating matrix 11 having a central junction or bridge portion 12. Two helical portions 13 and 14 extend integrally from the bridge portion, and the helical portions advance away from the bridge portion in opposite directions. Each helical portion extends around at least 360 degrees, and preferably about 420 to 540 degrees. The pitch of the helical turns is small, and adjacent windings are typically spaced apart by less than the axial width of the helical-portion turns, and preferably by about one-third the turn axial width.
Assembly 10 is a monopolar configuration having a single conductive electrode 16 secured on the inner surface of helical portion 13. The electrode is a thin and flexible metal ribbon embedded in the inner matrix surface, but with the inwardly facing surface of the ribbon fully exposed for electrical contact with a nerve. Depending on the type of nerve stimulation desired, the electrode may extend around a full turn of the helical portion, or somewhat less than a full turn as shown in FIG. 1.
A connection means for coupling the electrode to a source (not shown) of electrical signals is formed by a flexible multistrand wire 18 welded to the outer embedded surface of the electrode. The wire extends radially outwardly form the electrode to a small button or dimple 19 integrally formed with helical portion 13. The wire is bent 90 degrees within the dimple to extend parallel to the central axis of the helix, and is insulated by a surrounding tubular jacket 20 joined to the dimple.
FIG. 4 shows the inner surface of assembly 10 when unwound into a flat configuration. This view is provided only for clarifying the assembly structure, and the assembly is not constructed in flat form, nor is it normally distorted or unrolled to this condition during manufacture or use.
The electrode configuration and the spacing of the helical portions can be varied according to the planned nerve-stimulation program, and a typical variation is shown in FIGS. 2 and 3 as an electrode assembly 10A having a matrix 11A. In this second embodiment, bridge portion 12A is significantly lengthened to increase the axial spacing of oppositely directed helical portions 13A and 14A.
Both of these helical portions are provided with a pair of conductive electrodes 16 A-B and 16 C-D, and the electrodes of each pair may be driven by a double lead cable 18A (and 18B for electrodes 16 C-D), depending on the planned nerve-stimulation protocol. The insulated lead-wire jackets 20A and 20B are preferably joined by a drop of adhesive 21 and fitted into a surrounding tubular jacket 22 as they extend away from the assembly. Jacket 22 limits the bending radius of the connecting wire, and helps to prevent kinking, work hardening, and possible eventual breakage of wire strands during body movement.
The inside diameter of the helical portions is selected to be a close or very gently compressive fit on the nerve to be stimulated. Most peripheral nerves which are candidates for electrical stimulation have outside diameters in the range of about 1.0 to 7.0 millimeters, and this accordingly establishes the range of typical inside diameters of the helical portions. When electrodes are provided in both helical portions, bridge portion 12A will typically have an axial length in the range of 7 to 10 mm (though shorter or longer dimensions may be used) for effective stimulation and good evoked response at low power levels.
The supportive matrix of the assembly is preferably formed by a ribbon of medical-grade silicone elastomer, and an acceptable and commercially available uncured formulation is Dow Corning MDX4-4210. The connecting wires should have high flexibility and integrity, and a Teflon-coated 25-strand stainless-steel wire in a silicone-rubber jacket is satisfactory. The electrodes are preferably thin and high-purity annealed platinum ribbons about one millimeter in width and 0.025 mm thick for good flexibility. The ribbon is preferably surface roughened (abrasion with 25 micrometer diamond abrasive is a suitable technique) for increased effective area of the nerve-contacting face, and to enable mechanical bonding with the matrix material.
Prototype electrode assemblies have been made by the methods disclosed in the aforementioned U.S. Pat. No. 4,573,481. Briefly, and with reference to FIG. 9, an arbor or mandrel 25 is provided with a helical groove 26 corresponding in dimension to the desired geometry of the matrix. Each electrode 16 is fitted against the base of the groove, and is securely positioned an pressed against the groove base by a tightly wrapped strand 27 of 5-0 Dacron suture material. Intimate contact of the electrode against the mandrel is important to prevent any flow of silicone elastomer between the facing surfaces. Wire 18 is prewelded to the radially outer surface of the electrode, and the joint is insulated with an epoxy material such as sold under the trademark Epoxylite.
The liquid components of the silicone elastomer are then mixed and degassed to eliminate bubbles, and the elastomer is applied to the mandrel to fill groove 26 which defines the bridge and helical portions of the matrix. The elastomer is cured by heating to complete the formation of the assembly which is then gently stripped away from the mandrel. It is important that the cured matrix have good shape retention combined with high flexibility and resiliency, and the aforementioned silicone elastomer satisfies these requirements.
In a typical configuration, matrix 11 has a generally rectangular cross section, with an axial width of about 1.2 mm, and a radial thickness in the range of about 0.6 to 0.8 mm. The lower end of the thickness range is used for electrode assemblies intended for nerves of small diameter, and the larger thickness is selected for larger nerves to maintain approximately constant radial stiffness of the helical turns.
An installation tool 30 for the electrode assembly is shown in FIG. 5, and the tool is a modified surgical tweezer having a pair of legs 31 extending from a base junction 32 to tips 33. The legs are normally biased apart to separate tips 33, but the tips can be brought together by squeezing the tweezer in conventional fashion.
The tweezer is modified by addition of a pair of tines or pins 34, each of which is welded or brazed to a respective leg tip 33. The pins are parallel, and extend at about 45 degrees from the longitudinal axes of the legs. This angulation permits the pins to be oriented parallel to a nerve as described below, with the tweezer body extending upwardly away from the nerve for manipulation by the surgeon and good visibility of the electrode assembly. The pins are longer than the axial dimension of the electrode assembly to be installed, and are typically about 18 mm long.
Although the pins may have a simple circular cross section, a preferred trough-shaped cross section is shown in FIG. 8. The concave side of this cross section forms a shallow depression or seat 35 to receive the circumferential ends of the helical portions (or the corresponding end of the matrix bridge portion), and thus to support the opened electrode during the installation procedure described below. The trough-shaped cross section also minimizes pin size for fitting within helical assemblies of very small inside diameter.
Referring to FIGS. 6-7, a peripheral nerve 36 is surgically exposed in preparation for installation of electrode assembly 10. Pins 34 of the installation tool are compressed together by squeezing the tweezer, and the adjacent pins are slipped through the hollow interior of the helical electrode assembly. Gripping force on the tweezer is then relaxed, permitting the pins to separate and thereby open the electrode assembly so it can be lowered over nerve 36 as shown in FIG. 6.
Tool 30 is initially positioned within the electrode assembly such that when the pins are separated, one pin will be close to bridge portion 12, and the other pin will be adjacent the free ends of helical portions 13 and 14. The resulting unwrapping or unwinding of flexible matrix 11 and associated electrode or electrodes opens the helical turns to form a laterally open passage 37 to receive the nerve as shown in FIG. 8.
When the spread electrode assembly has been placed over the top of the nerve, the tweezer pins can be moved toward each other beneath the nerve, and continued lowering of the tweezer tips withdraws the pins from within the electrode. The tweezer is then sufficiently reopened to provide clearance between the pins and the nerve so the tool can be withdrawn.
When the tool pins are removed, the shape memory of resilient matrix 11 causes an automatic self-closing action of helical portions 13 and 14 around nerve 36. The preferred slight compressive fit of the helical portions places the electrode or electrodes in the desired intimate contact with the nerve for good electrical conduction of stimulating signals.
In some implantations of the electrode assembly, there may be only a very slight clearance between the undersurface of the nerve and the underlying body structure. In this situation, the electrode assembly is fitted over the nerve as already described, and the tool pins are then compressed together and gently withdrawn from the electrode matrix by a sideways movement parallel to the nerve axis. The tips are then again spread sufficiently to be withdrawn over the opposed sides of the nerve.
Separation of the installation-tool pins within the helical portions causes unwinding of the helical turns by a sliding movement of the matrix inner surface on the pins. Preferably, the pins are Teflon coated to minimize frictional resistance to this sliding motion of the silicone-rubber matrix over the pins.
In common with the helical electrode of my earlier aforementioned patent, the new electrode assembly has the significant advantages of minimum interference with desirable fluid exchange between the nerve and surrounding tissue, and minimum risk of excessive nerve compression which can cause nerve damage. The new assembly is even more capable of resiliently accommodating nerve swelling or edema resulting from the implantation surgery. Similarly, the assembly has good longitudinal flexibility to accommodate bending of the associated nerve during limb articulation or other body movement. Good electrical contact of the electrode and nerve is also achieved, with little risk of tissue-ingrowth problems encountered with cuff electrodes.
The oppositely directed turns of the helical portions provide an important advantage of good assembly anchorage and resistance to axial movement of the assembly along the nerve in response to adjacent muscle movement or limb articulation. The anchoring effect arises from an opening separation of the distal helical portion which reduces the matrix inside diameter to increase the gripping action of the matrix around the nerve. The tight pitch of the helical portions, and the capability of using multiple electrodes, enables use of multiple stimulus sites along and around the nerve for selective stimulation of nerve bundles.
Apart from these important features, an outstanding advantage of the new assembly is ease of installation, and freedom from any need to wind the assembly manually around the nerve. In addition to reducing surgical manipulation and possible nerve trauma, the simple open- lower-close installation sequence permits placement even when the exposed nerve is deeply recessed in the body with very small undersurface clearance.
Although described above in terms of an assembly with two helical portions of opposite rotation direction, the invention extends to a single helical portion which is useful where axial exposure of the nerve is limited. In both configurations, the helical turn extends around at least 360 degrees to provide complete encirclement of the nerve, and preferably about one-half turn beyond a full circle. If desired, the electrode ribbon may extend along the entire inner circumference of the helical matrix to provide constant stiffness, and any unwanted conductive contact is avoided by applying an insulating coating (Epoxylite is suitable) to portions of the exposed electrode surface.
The extent of the matrix helical turn is preferably kept less than two full turns for several reasons. First, a greater circumferential extent of the helical portion requires a greater separation of the installation-tool pins to open the assembly for fitting over the nerve, and this separation should be minimized so the tool pins can be fitted within a narrow incision. A second factor is to limit distortion of the electrode ribbon which may decrease the desired intimate contact of the electrode against the nerve surface.
There has been described an electrode assembly which incorporates the important advantages of my earlier design, while offering a significant improvement in ease of installation over a nerve to be electrically stimulated. | A circumneural electrode assembly having a pair of spaced-apart and oppositely directed helical portions which can be opened by an insertion tool to fit the assembly over a peripheral or cranial nerve. One or more conductive electrodes on the inner surfaces of the helical portions intimately contact the nerve surface to deliver electrical stimulating signals, or alternatively, to block nerve conduction or to sense evoked potentials. The surgically implanted assembly is stable in position on the nerve, and is installed with a minimum of nerve manipulation and possible resulting trauma. The assembly preserves the advantages of previously disclosed spiral electrodes, while greatly simplifying installation, particularly in a nerve which is deeply recessed in overlying muscle or arteries. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
In treating pediatric patients with various diseases that may include post-operative, ophthalmologic, cardiological, neurological, and gastro-entrological, including gastroesophagic reflux (“GER”), the treatment may require the patient to be placed in an incline position. This physical position therapy utilizes the force of gravity to maintain bodily fluids and tissues down in the body. Typically, physicians and patients improvise treatments that include restraints and blockages that are not always safe or effective. Additionally, one treatment requires keeping the baby constantly seated in a baby chair, however this procedure, besides being very uncomfortable, may result contraindicated.
2. Description of the Related Art
U.S. Pat. No. 4,862,535 issued to Roberts, discloses a therapeutic device for positional treatment of GER which consists on an anti-reflux pillow, comprising a wedge shaped support pillow having an inclined infant-supporting surface, with a diaper-like infant torso encircling sling, attachable to the infant supporting surface of the support pillow. Two parallel strips of VELCRO® fastener adhesive material are attached at the opposite lateral edges of the torso encircling sling and the inclined surface of the supporting pillow. The infant is secured inside the torso encircling sling with two parallel sets of snap fasteners that close the sides of the torso encircling sling. The wedge shaped supporting pillow is soft and deformable to create a cavity where the infant is placed.
Since the infant in the Roberts disclosure is attached to the supporting surface of the supporting pillow by the torso, the device therein permits free movement of the arms and legs but not of the mentioned attached torso. The device in Roberts does not permit the use of bottom sheets under the infant. In addition, the infant in the Roberts disclosure is uncomfortable since he/she is obviously prevented from moving his/her torso while being attached to the supporting pillow precisely by the torso.
Roberts describes, in the background of the patent document, that the arrangement is intended for use with weak and tiny infants placed in intensive care nurseries. However, not all infants that need this kind of positional therapy are tiny and weak, and not all of them are attended at intensive care nurseries. If a bigger or stronger infant is placed on the Roberts' arrangement, the infant will surely pull or move forcefully enough to unfasten the sets of simple snap fasteners that close the sides of the torso encircling sling and/or the VELCRO® fastening strips that fasten the torso encircling sling to the infant supporting surface of the mentioned supporting pillow. A strong restless infant may also pull the sling or lateral fastener means with his own hands and fall from the pillow.
Yet another problem with the Roberts pillow is that the infant can not be placed in a lateral position as many physicians prefer. This system necessitates the use of a special wedge shaped pillow or support system with the torso encircling sling, thus making it more complicated and expensive.
Further, a danger arises when an infant is laid prone on a surface like the Roberts' pillow where the infant's face may sink into the pillow and suffocate if breathing is obstructed. This danger is magnified if one considers the possibility of the infant vomiting with or without GER (gastroesophagic reflux).
Another danger with the Roberts' arrangement is the support system or wedge shaped pillow being filled with Styrofoam® balls. This material is so light that an uneasy infant attached to it making a strong lateral movement may cause the entire device to turn upside down, thus traps the infant inside.
There is a great need for an infant positioning container that is safe, comfortable and inexpensive, and suitable for tiny or big, weak or strong, calm or uneasy infants, staying at home or in an intensive care nursery. It would be desirable for the container to allow easy and quick access to the infant in case of urgency, while being usable on any bed, cradle, crib, baby basket, incubator mattress, or on a special wedge shaped mattress, if desired. It would be securable if the container allowed the infant be laid prone supine or lateral, allowed the infant to move its legs, arms or torso freely, and allowed the use of a removable bottom sheet under the infant. It would be useful if no matter how big, heavy, strong or restless the infant could be, he/she would not be able to release himself with his hands, movements or weight. It would be desirable if the container is adjustable, easy to change and washable, or, in the alternative, made of disposable materials. It would further be important for the container to be inexpensive and simple to construct compared to the existing systems.
SUMMARY OF THE INVENTION
The main objective of the present invention is to aid pediatric physicians and caregivers along with parents and relatives of infants to safely lay the infants in an inclined position, as shown in FIGS. 11 and 12, whether they are placed in a basket, incubator, bassinet, cradle or on bed mattress at a nursery or at home, thus overcoming the problems and insufficiencies of prior inventions.
Another objective of the present invention is to be useful for the positional treatment of tiny and weak, heavy, strong or big infants on their bed, cradle, baby basket, incubators, bassinets, mattresses, without the need for a special wedged shaped pillow or mattress, if used with the strap system shown in FIGS. 4, 5 and 12 , or with the mattress cover option shown in FIGS. 6, 7 and 11 .
Another objective of this invention, is to permit fast and easy access to the infant in case of urgency, but still avoiding the possibility that the infant could release himself with his own hands, movements or weight, no matter how big, heavy, strong or uneasy the infant is.
Another objective of the present invention is to permit the caregivers to remove the device easily for washing or moving the baby and device together, or to replace the device with a clean one or one of a different size, depending upon the size of the infant, as shown in FIGS. 1, 2 and 3 .
Another objective of the present invention is to permit the infant to be laid prone, supine or laterally.
Another objective is to permit the infant to move his/her arms, legs and torso freely, letting the infant feel less confined, more comfortable and avoid the danger of falling or moving from the desired position.
Another objective is to permit the device to be graduated while the infant grows, as shown in FIG. 8 .
Another objective is to permit the use of disposable materials in the construction of the infant fastening device, when convenient.
These and other objectives of the present invention are made possible with the provision of an infant fastening device, which includes a fastening system that can be attached to any cradle, bed or basket, ordinary or special mattress at home, or in warmers and isolators in nurseries and hospitals.
This invention is intended to fulfill the need for an appropriate tool for the treatment of infants that require the above described kind of positional therapy.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the bag shaped infant container of the present invention closed on a frontal view to show its main parts.
FIG. 2 is a detailed perspective view of the superior winged, “V” shape, sandwich type fastening arrangement of the infant container.
FIG. 3 is a detailed perspective view of the superior winged “V” shape, sandwich type fastening arrangement, with snap clasps instead of Velcro® fasteners attaching material.
FIG. 4 is a perspective view showing the rectangular shaped attaching tongue of the present invention mounted on the superior side of a common inclined mattress with the strip attaching system option.
FIG. 5 is a perspective view of the complete strip system without mattress.
FIG. 6 is a perspective view of the rectangular shaped attaching tongue shown sewn to the superior side of the cover of a common mattress.
FIG. 7 presents a perspective rear view of the winged “V” shaped sandwich type superior fastener, closed over the inner attaching tongue.
FIG. 8 presents a detailed perspective view of one lateral edge of the infant container showing the strips with clasps and rings attachment system, also showing how it can be adjusted up or down.
FIG. 9 is a perspective view of the bag shaped infant container, opened to show all of its pieces extended.
FIG. 10 is a perspective view of a closed infant container, turned back to show four lateral strips with clasps snapped back and four lateral strips with clasps snapped.
FIG. 11 is a perspective view showing the use of the infant container, with an infant laying prone on it, over a common inclined mattress.
FIG. 12 is a perspective view, presenting the infant container attached to a special wedge shaped mattress, with the strip system of the present invention.
DESCRIPTION OF THE INVENTION
FIG. 1 is a perspective view of the bag shaped infant container of the present invention closed on a frontal view to show its main parts.
In FIG. 1, the following identified elements are shown:
( 1 ) Rear or back rectangular long piece.
( 2 ) Front shorter rectangular piece.
( 3 ) Superior or top edge of the back piece, with the winged “V” shaped attaching arrangement opened.
( 4 ) Inferior or bottom edge of the back piece showing the rounded corners.
( 5 ) & ( 6 ) Lateral sides of rear ( 1 ) and front ( 2 ) rectangular pieces.
( 7 ) Superior edge of the rectangular shorter front piece ( 2 ).
( 8 ) Arcuate cutouts on the inferior edge of the front shorter rectangular piece ( 2 ).
FIG. 2 is a detailed perspective view of the superior winged, “V” shape, sandwich type fastening arrangement of the infant container.
In FIG. 2 the following identified elements are shown:
( 9 ) & ( 10 ) Exterior surfaces of the winged rectangular shaped pieces, attached to the superior edge of the back piece ( 1 ) of the infant container (not shown), forming a “V” shape opened to show both inner surfaces.
( 11 ) & ( 12 ) Strips of Velcro® fastener plush attaching material, applied along the interior surface of the winged “V” shape, superior attaching arrangement.
( 14 ) Superior rectangular shaped, fastening tongue.
( 15 ) Strips of Velcro® fastener hook adhesive material applied along the exterior surfaces of the superior, rectangular shape fastening tongue (opposite surface not shown.)
FIG. 3 is a detailed perspective view of the superior winged “V” shape, sandwich type fastening arrangement, with snap clasps instead of Velcro® fastener attaching material.
In FIG. 3 the following additional examples are shown:
( 13 ) Clasps attached to the inner surface of the winged “V” shape, superior fastening arrangement.
( 16 ) Clasp counters, attached to the exterior surfaces of the rectangular shaped attaching tongue (opposite surface not shown.)
FIG. 4 is a perspective view showing the rectangular shaped attaching tongue of the present invention mounted on the superior side of a common inclined mattress with the strip attaching system option.
In FIG. 4 the following additional elements are shown:
( 17 ) Superior elevated side of a common mattress.
( 18 ) Tongue and strip mounting system, attached to a mattress.
FIG. 5 is a perspective view of the complete strip system without mattress.
FIG. 6 is a perspective view of the rectangular shaped attaching tongue shown sewn to the superior side of the cover of a common mattress. In FIG. 6 the following additional element is shown:
( 19 ) mattress cover.
FIG. 7 presents a rear perspective view of the winged “V” shaped sandwich type superior fastener, closed over the inner attaching tongue.
FIG. 8 presents a detailed perspective view of one lateral edge of the infant container showing the strips with clasps and rings attachment system, also showing how it can be adjusted up or down.
In FIG. 8 the following additional elements are shown:
( 20 ) Strip with snap type clasp.
( 21 ) Snap type clasp counter section applied near the junction of the strip with the lateral edge of the back piece of the infant container.
( 22 ) Rings attached to the lateral edge of the front piece of the infant container.
( 23 ) Strip with clasp and ring attachment arrangement
FIG. 9 is a perspective view of the bag shaped infant container, opened to show all of its pieces extended.
In FIG. 9 the following additional elements are shown:
( 24 ) The central portion left between the arcuate cutouts of the front piece, attached to a central position between the rounded corners of the bottom edge of the back piece of the infant container.
FIG. 10 is a perspective view of a closed infant container, turned back to show four lateral strips with clasps snapped back and four lateral strips with clasps unsnapped.
FIG. 11 is a perspective view showing the use of the infant container, with an infant laying prone on it, over a common inclined mattress.
FIG. 12 is a perspective view, presenting the infant container attached to a special wedge shaped mattress, with the strip system of the present invention.
The present invention consists of an infant container, with the shape of a bag made with cloth or disposable material as shown in FIG. 1 . This bag shaped infant container is made with two main pieces, a rear piece ( 1 ) and a front piece ( 2 ). The rear piece ( 1 ) of the container is longer than the front piece ( 2 ), and is rectangular in shape, comprising a superior or top side ( 3 ), an inferior or bottom side ( 4 ) with rounded corners and two lateral sides ( 5 ) and ( 6 ). The front piece ( 2 ) is shorter than the rear piece, but is also rectangular with a superior or top side ( 7 ) and inferior or bottom side, with two arcuated cutouts ( 8 ) on each corner and two lateral sides that coincide with the lateral sides ( 5 ) and ( 6 ) of the rear piece ( 1 ).
Along the superior side ( 3 ) of the mentioned rear piece ( 1 ) is a winged “V” shaped “sandwich type” fastening arrangement detailed in FIGS. 2, 3 and 7 . This arrangement is made of two rectangular pieces of cloth or disposable material ( 9 ) and ( 10 ), attached along the superior edge of the rectangular rear piece ( 3 ), forming a winged “V” shaped arrangement. This so-called winged “V” shaped arrangement has two exterior surfaces ( 9 ) and ( 10 ) and two interior surfaces ( 11 ) and ( 12 ). Applied along the mentioned interior surface of each “wing” of the “V” shaped arrangement is a strip of the plush side of VELCRO® fastener adhesive material ( 11 ) and ( 12 ) or in an alternative embodiment, a set of clasps ( 13 ), as shown in FIG. 3 .
A rectangular shaped tongue ( 14 ) made of cloth or disposable material having two sides or opposite surfaces along each side or surface of the mentioned rectangular shaped tongue ( 14 ) is applied a strip of VELCRO® fastener hook side adhesive material ( 15 ) or in an alternative embodiment a set of clasps ( 16 ), as shown in FIG. 3 . The rectangular shaped tongue ( 14 ), covered with VELCRO® fastener hooks or with clasps applied on its surfaces, is attached to the elevated side of an inclined mattress ( 17 ) as shown in FIG. 4, by a strip fastening ( 18 ) in arrangement FIGS. 4, 7 and 11 , or sewn to the cover of the mattress ( 19 ) in FIGS. 6, 7 and 11 .
VELCRO® fastener is an adhesive stripped material, made of two strips that attach to each other, one of the strips is made on its adhesive surface of a “plush-like” material. The other strip is made on its adhesive surface, of a hook-like material, when these surfaces of the mentioned hook and plush strips are joined together, they attach to each other.
Once the rectangular shaped tongue ( 14 ) is sewn to the superior side of the cover on an inclined mattress or attached to it with the fastening strip arrangement, the superior edge of the rear rectangular piece is opened to expose the “V” shaped fastening arrangement, which is inserted in the fastening tongue ( 14 ). The wings are then closed over as shown in FIG. 7 . This double surface, positioned high on the infant container and only on the superior side of it, allows all of the torso of the infant free to move, permits the use of bottom sheets under the infant and leaves the infant comfortable, permitting the infant to lay laterally and allowing the fast and easy release of the infant if necessary.
Lengthwise along the lateral edges of the rear piece of the infant container as best seen in FIGS. 8, 11 and 10 , is placed a set of strips with a snap clasp on each strip ( 20 ). Lengthwise along the lateral sides of the front piece of the infant container as best seen in FIGS. 8 and 9, is placed a set of rings ( 22 ). Near the union of each strip ( 20 ) with snap clasp, on the edge of the mentioned rear piece of the infant container, is placed a clasp counter ( 21 ). The strips with clasps means ( 20 ) are passed through the inside of the rings ( 22 ) and turned back to be attached to the counter of the clasp means, placed on the lateral edge of the rear piece ( 23 ) of the infant container. This strip with clasp and ring fastening system is highly resistant and depending on the number of strips with clasp and rings that are attached, the front piece can be lengthened while the infant grows. | This invention provides an aid to pediatric physicians and caregivers to lay an infant in incline position for use in treating various physical conditions or diseases, including gastroesophagic reflux (“GER”). The device allows for positional treatment of infants without the need for a special wedged shaped pillow or mattress. The invention allows for fast and easy access to the infant in case of urgency, but still avoids the possibility of the infant releasing himself. The device can be removed for washing or replacement of a new device, depending upon the size of the infant. The device allows the infant to be laid prone, supine, or laterally. | 0 |
TECHNICAL FIELD
[0001] The present application relates to an element applied to a vehicle chassis, which falls into the technical field of a passenger or commercial vehicle and is an innovative vehicle suspension system.
BACKGROUND ART
[0002] A suspension is a general title for any transmission force connecting means between a vehicle frame (axle) and wheels, which is intended to transmit a force acting between the wheels and the vehicle frame, and to dampen an impact transferred to the vehicle frame or vehicle body from an uneven road surface, and to attenuate vibrations caused thereby, so as to ensure smooth running of the vehicle.
[0003] Early vehicles usually take rigid axle suspensions in which leaf springs serve as elastic elements. Later on, leaf springs were replaced by coil springs, torsion bar springs, air springs, rubber springs, hydro-pneumatic springs and so on. At present, high-level vehicles generally employ independent suspensions, such as transverse arm type, trailing arm type, single oblique arm type, sliding pillar type, Macpherson type, multi-link and active suspension, etc.
[0004] A double wishbone independent suspension is a widely used suspension type. The double wishbone independent suspension has a rather small surrounding space, and is staggered with the power shaft, steering rod, balance bar and elastic element within the same space. That is, elastic elements and shock absorbers are suspended from it at a single point vertically. Over the years that the double wishbone independent suspension has been put into application, due to such factors as having too many structural parts, ever-changing environment, frequent change in carrying, continuous work, limited bearing point space, and the like, no modification or innovation has been made thereto.
SUMMARY OF INVENTION
[0005] An output type multi-bearing-point independent suspension according to the present application is an innovative independent suspension system. Appropriate symmetric bearing points are selected by computing with the principle of moments. Corresponding available space is expanded around the upper fork arm and the lower fork arm, to construct appropriate bearing points and transmission parts of the vehicle frame. By utilizing the lever principle, the torsion bar principle and the principle of moments, double fork arm shaft hanging point motion can absorb bearing elastic force by means of changing directions of force and the arms of force, so as to change points supporting an elastic elements and to form multiple points supporting a plurality of elastic elements, such that the force applied on the wheel is distributed by multiple points. At the same time, applying mechanical principles, different elastic elements may be used to allow the suspension to be adapted to vehicle technical requirements, so as to improve the technical parameters of the running system.
[0006] The present application is intended to expand the useful space of the vehicle suspension, with duplex calculation, so as to position and adjust the vehicle frame bearing structure, and to adjust and modify the vehicle frame bearing structure into a new bearing structure by changing a single-point load bearing arrangement into a multi-point bearing decomposition arrangement, and replace a single group of elastic elements with multiple groups of elastic elements to thereby provide smooth and safe running, and a comfortable riding experience.
[0007] The present application comprises an upper fork arm, a lower fork arm, elastic elements, a shock absorber and fork arm positioning shafts; the upper fork arm and the lower fork arm are A-shaped structural parts, the front ends of the upper fork arm and the lower fork arm are respectively connected with the upper suspension point and lower suspension point of a wheel through main pins, and the rear ends of the upper fork arm and/or the lower fork arm are connected with a vehicle frame through the elastic elements, the shock absorber is mounted on top of the front end of the upper arm. On this basis, there are five technical solutions:
[0008] According to a first aspect of the application, there is provided an arm direct transmission independent suspension, wherein the middle portions of the upper and lower fork arms are connected to the vehicle frame by fork arm positioning shafts respectively, and an elastic member is provided between the bottom of the rear end of the upper fork arm and the vehicle frame. An elastic member may be provided between the bottom of the rear end of the lower arm and the vehicle frame.
[0009] According to a second aspect of the present application, there is provided a torsion bar direct transmission independent suspension, wherein the rear ends of the upper and lower fork arms are connected to the vehicle frame by a torsion bar and a torsion bar seat.
[0010] According to a third aspect of the application, there is provided a link rod joint transmission independent suspension, wherein the rear ends of the upper and lower fork arms are respectively connected to the vehicle frame by a fork arm positioning shaft, and two fork arm hanging pivots extend from a bottom of the front portion of the upper fork arm, each fork arm handing pivot having a lower end connected with an output lever by a link rod, and a middle portion of the output lever is hinged to the vehicle frame by means of an output lever rotating shaft and an elastic element is arranged between a bottom of another end of the output lever and the vehicle frame. Two fork arm hanging pivots may also extend from a bottom of the front portion of the lower fork arm, and each fork arm hanging pivot is connected to the output lever by means of a link rod, and a middle portion of the output lever is hinged to the vehicle frame by means of an output lever rotating shaft and an elastic element is arranged between a bottom of another end of the output lever and the vehicle frame.
[0011] According to a fourth aspect of the application, there is provided an angled arm transmission independent suspension, wherein rear ends of the upper and lower fork arms are connected respectively to the vehicle frame by a fork arm positioning shaft, and each of opposite sides of a front portion of the upper fork arm is hinged with a connecting arm, and another end of the connecting arm is hinged to an end of the right-angled output arm, and another end of the right-angled output arm is connected with an elastic element, and another end of the elastic element is fixed to the vehicle frame. The right-angled output arm has a right-angled output arm rotating shaft, and the right angled output arm rotating shaft is pivotally connected to the vehicle frame. Each of opposite sides of a front portion of the lower fork arm may also be hinged with a connecting arm, and another end of the connecting arm is hinged to an end of the right-angled output arm, another end of the right-angled output arm is connected with an elastic element, and another end of the elastic element is fixed to the vehicle frame. The right-angled output arm has a right-angled output arm rotating shaft, and the right angled output arm rotating shaft is pivotally connected to the vehicle frame.
[0012] According to a fifth aspect of the present application, there is provided a torsion spring direct transmission independent suspension, wherein rear ends of the upper and lower fork arms are connected to the vehicle frame by a torsion bar and a torsion bar seat, and a shock absorber is mounted between the top of the front end of the upper fork arm and the vehicle frame. Up and down bouncing of the wheel brings about an upward movement of the front end of the upper fork arm, and the upper fork arm rotates about a rear fixing point, such that two torsional springs arranged symmetrically on two sides produce a torsional deformation which has the effect of shock absorption. A shock absorber is mounted on the top of the front end of the upper fork arm. In operation, the wheel brings about upward bouncing of the suspension point of a front wheel, and the shock absorber has a dampening effect. When the wheel bounces up and down, the shock absorber and the torsion spring bear forces on multiple points which act in cooperation. Moreover, the upper and lower fork arms may each be provided with a torsion spring elastic element, such that more hanging points may distribute the impact produced by bouncing of the wheels, so as to produce a better shock absorption effect.
[0013] The present application in which a balanced lever is used to transmit force to an output lever avoids the situation in which the momentum of the vertical upward impact on the vehicle body is transmitted by a single point, such that the fork arm positioning shaft serves as a fulcrum, such that the other two hanging points are movable within the vehicle horizontally, vertically and perpendicularly, to compress the elastic elements, and change the direction of the forces so as to reduce the impact on the vehicle.
[0014] By duplex calculation, the bearings are located, and selection of positions of fork arm hanging shafts, link rods and so on as well as layout of levers are determined, resulting in effective use of space, finding the target of new multiple hanging and bearing points and a stable structure, to achieve an articulated bearing of an axleless vehicle frame and the suspension in which a new axleless frame may be used in cooperation.
[0015] The present application, based on the condition of double fork arms, fork arm positioning shafts and output lever trajectory, selects appropriate position of the fork arm or the fork arm hanging shaft with the lever principle and scientific calculation, and a corresponding solution for selection of the direction and position of the final bearing points which output the force can be selected according to the vehicle frame space and structure.
[0016] The use condition of the present application is that a traditional vehicle frame is difficult to be adapted to achieve the effect, but a wheel-beam type axleless vehicle frame should be used therewith.
[0017] The present application has advantageous effects as the following:
[0018] 1. Effective and integrated use of existing space, with a single force bearing point scattered into a number of force bearing points, capable of changing the direction of force, without affecting the layout and functions of other parts, and enhancing the overall vehicle running performance.
[0019] 2. One end of the suspension directly connected to the wheel, impact load distributed on multiple points, with direction changed, so that the average driving speed is increased.
[0020] 3. Increase in the number of elastic elements, and reasonable layout thereof, can reduce the height of the vehicle, optimize space utilization, and enhance the stability of the vehicle and riding comfort.
[0021] 4. Adjustable wheel jumping movement stroke and elastic element force bearing section arrangement.
[0022] 5. Easy to set the chassis height according to different road conditions.
[0023] 6. To be used with such a running system as an axleless vehicle frame, capable of accelerating development of electrical, light weighted, and intelligent vehicle.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] FIG. 1 is a side view of a first embodiment according to the present application in which a fork arm positioning shaft is provided (referred to as a fork arm direct transmission independent suspension).
[0025] FIG. 2 is a top view of the embodiment of FIG. 1 .
[0026] FIG. 3 is an isometric view of the embodiment of FIG. 1 .
[0027] FIG. 4 is a schematic view of the embodiment of FIG. 1 .
[0028] FIG. 5 is a view of a second embodiment according to the present application in which a torsion bar twisting around an axis of a fork arm positioning shaft is provided (referred to as a torsion bar direct transmission independent suspension).
[0029] FIG. 6 is a side view of the embodiment of FIG. 5 .
[0030] FIG. 7 is a top view of the embodiment of FIG. 5 .
[0031] FIG. 8 is an axonometric view of the embodiment of FIG. 5 .
[0032] FIG. 9 is a cross-sectional view of a third embodiment according to the present application in which an output lever is provided (referred to as a link rod joint transmission independent suspension).
[0033] FIG. 10 is a top view of the embodiment of FIG. 9 .
[0034] FIG. 11 is an isometric view of the embodiment of FIG. 9 .
[0035] FIG. 12 is a principle illustrative view of the embodiment of FIG. 9 .
[0036] FIG. 13 is a cross-sectional view of a fourth embodiment according to the present application in which a right-angled output arm is provided (referred to as an angled arm transmission independent suspension).
[0037] FIG. 14 is a top view of the embodiment of FIG. 13 .
[0038] FIG. 15 is an isometric view of the embodiment of FIG. 13 .
[0039] FIG. 16 is a schematic view of the embodiment of FIG. 13 .
[0040] FIG. 17 is a cross-sectional view of a fifth embodiment according to the present application in which a torsion spring twisting around an axle of a fork arm positioning shaft is provided (referred to as a torsion spring direct transmission independent suspension).
[0041] FIG. 18 is a side view of the embodiment of FIG. 17 .
[0042] FIG. 19 is a top view of the embodiment of FIG. 17 .
[0043] FIG. 20 is a top view of the embodiment of FIG. 17 .
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0044] Interpretation of Terms:
[0045] Fork arm positioning axis point: fork arm positioning axis point as recited in the present application refers to rotation axis point at which the upper or lower fork arm rotationally connected with the vehicle frame.
[0046] Fork arm shaft hanging point: fork arm shaft hanging point as recited in the present application refers to fixed rotation axis point of a newly built link rods of upper or lower fork arm.
[0047] Support pillar axis point: support pillar axis point as recited in the present application refers to pillar axis point which supports the output lever or right-angled output arm and is in the same position as rotation axis of output lever or right-angled output arm.
[0048] Front and rear end pivot points of the output rod: front and rear end pivot points of the output rod as recited in the present application, front end pivot point refers to rotation points of link rod and the output lever or right-angled output arm, and the rear end pivot point refers to connecting axis point of elastic element or shock absorber element.
[0049] In order to enable a person skilled in the art to understand the description of the present application more clearly, some terms indicating direction and position are clarified as below: “front end”, “front portion” of upper fork arm 1 and lower fork arm 2 refer to position adjacent to apex of an A-shaped structural element of the upper fork arm 1 and the lower fork arm 2 ; “rear end” refers to position away from apex of the A-shaped structural element; “top” and “bottom” are each based on position as shown in FIG. 1 . “Middle portion” represents a portion adjacent to an intermediate position of the upper fork arm 1 and the lower fork arm 2 .
[0050] The present application can be implemented in the following embodiments:
A First Embodiment: Fork Arm Direct Transmission Independent Suspension
[0051] This embodiment employs a manner of changing direction of force by a fork arm positioning shaft, and is shown in FIGS. 1, 2 and 3 .
[0052] The independent suspension of this embodiment comprises an upper fork arm 1 , a lower fork arm 2 , elastic elements 3 , a shock absorber 4 and fork arm positioning shafts 5 ; the upper fork arm 1 and the lower fork arm 2 are A-shaped structural elements, front ends of the upper fork arm 1 and the lower fork arm 2 are respectively connected with an upper suspension point and a lower suspension point of a wheel C through main pins B, middle portions of the upper fork arm 1 and lower fork arm 2 are connected to the vehicle frame by fork arm positioning shafts 5 respectively, and an elastic element 3 is provided between a bottom of the rear end of the upper arm 1 and the vehicle frame.
[0053] An elastic element 3 may also be provided between a bottom of a rear end of the lower fork arm 2 and the vehicle frame, as shown in FIG. 4 .
[0054] Rear ends of the upper fork arm 1 and lower fork arm 2 extend to form levers. By means of changing direction by the fork arm positioning shaft 5 , an upward movement stroke of the front end of the upper fork arm 1 is changed into a downward movement stroke, and the downward movement stroke acts on two elastic elements 3 disposed symmetrically on the rear ends, so as to produce the effect of shock absorption. Rear extension sections of the upper fork arm 1 and the lower fork arm 2 , as required by spatial position, may extend directly, or deflect by an angle inwardly, outwardly, upwardly or downwardly, to form a plurality of arrangements so as to be adapted to various vehicle types or vehicle frames. A shock absorber 4 is mounted on top of the front end of the upper fork arm 1 . In operation, when the wheel brings about upward bouncing of the front end of the upper fork arm 1 suspension point, the shock absorber 4 produces a dampening effect.
[0055] The elastic element 3 is disposed according to position and manner. The elastic element 3 of the upper fork arm 1 may be provided as an air spring. As for the lower fork arm 2 , due to spatial position limitations, its elastic element 3 may comprise an elastic rubber block having a small size or an elastic element having a corresponding size. When the wheel bounces up and down, the shock absorber 4 and the elastic elements 3 are subject to forces simultaneously and act in cooperation. Elastic element 3 may be disposed only on the upper fork arm 1 , or may be disposed both on the upper fork arm 1 and the lower fork arm 2 which may produce a better shock absorption effect.
A Second Embodiment: Torsion Rod Direct Transmission Independent Suspension
[0056] This embodiment employs is a manner of twisting a torsion bar around an axis of a fork arm positioning shaft, and is shown in FIGS. 5, 6, 7 and 8 .
[0057] The independent suspension of this embodiment comprises an upper fork arm 1 , a lower fork arm 2 , fork arm positioning shafts 5 , torsion rods 6 , a shock absorber 4 and torsion rod seats 7 . The upper fork arm 1 and the lower fork arm 2 are A-shaped structural elements, front ends of the upper fork arm 1 and the lower fork arm 2 are respectively connected with an upper suspension point and a lower suspension point of a wheel C through main pins B, rear ends of the upper fork arm 1 and lower fork arm 2 are connected to the vehicle frame by a torsion rod 6 and a torsion rod seat 7 , and a shock absorber 4 is mounted between top of the front end of the upper arm 1 and the vehicle frame.
[0058] Bouncing of the wheel C brings about an upward movement of the front end of the upper fork arm 1 , and the upper fork arm 1 rotates about a rear fixing point, such that two torsion rods 6 arranged symmetrically on two sides produce a torsional deformation which has the effect of shock absorption. A shock absorber 4 is mounted on top of the front end of the upper fork arm 1 . In operation, the wheel C brings about upward bouncing of the suspension point of the wheel, the shock absorber 4 which has a dampening effect. Said shock absorber 4 is mounted between the front end of the upper fork arm 1 and the vehicle frame, when the wheel bounces up and down, the shock absorber 4 and the torsion rod 6 are subject to forces on multiple points simultaneously and act in cooperation. Moreover, the upper and lower fork arms may each be provided with torsion rods, such that more hanging points may distribute the impact produced by bouncing of the wheels, so as to produce a better shock absorption effect.
A Third Embodiment: Link Rod Joint Transmission Independent Suspension
[0059] This embodiment employs a manner of outputting by an output lever, and is shown in FIGS. 9, 10 and 11 .
[0060] The independent suspension of this embodiment comprises an upper fork arm 1 , a lower fork arm 2 , fork arm positioning shafts 5 , a link rod 8 , an output lever rotating shaft 9 , an output lever 10 , an elastic element 3 and a shock absorber 4 . The upper fork arm 1 and the lower fork arm 2 are A-shaped structural elements. Front ends of the upper fork arm 1 and the lower fork arm 2 are respectively connected with an upper suspension point and a lower suspension point of a wheel C through main pins B, and rear ends of the upper fork arm 1 and lower fork arm 2 are connected to the vehicle frame by a fork arm positioning shafts 5 respectively. Two fork arm hanging pivots 81 extend from a bottom of the front portion of the upper fork arm 1 . Each fork arm hanging pivot 81 is connected to the output lever 10 by means of a link rod 8 . A middle portion of the output lever 10 is hinged to the vehicle frame by means of an output lever rotating shaft 9 and an elastic element 3 is arranged between a bottom of another end of the output lever 10 and the vehicle frame. The shock absorber 4 is mounted between top of the front end of the upper fork arm 1 and the vehicle frame.
[0061] Two fork arm hanging pivots 81 may also extend from a bottom of the front portion of the lower fork arm 2 ; each fork arm hanging pivot 81 is connected to the output lever 10 by means of a link rod 8 ; a middle portion of the output lever 10 is hinged to the vehicle frame by means of an output lever rotating shaft 9 ; and an elastic element 3 is arranged between a bottom of another end of the output lever 10 and the vehicle frame, as shown in FIG. 12 .
[0062] The output lever 10 is configured to change an upward movement stroke of the front end of the upper fork arm 1 into a downward movement stroke of the output lever 10 by means of rotating around the fork arm positioning shaft 9 , and the downward movement stroke acts on two elastic elements 3 disposed symmetrically on the rear ends, so as to produce the effect of shock absorption. As required by spatial position, the output lever 10 may be provided in parallel to a side of the upper fork arm, or deflect by an angle outwardly, to form a plurality of arrangements so as to be adapted to various vehicle types (vehicle frames). A shock absorber 4 is mounted on top of the front end of the upper fork arm 1 , to co-act with the elastic elements 3 to produce shock absorption and dampening effect. Said shock absorber 4 is mounted between the front end of the upper fork arm and the vehicle frame, when the wheel bounces up and down, said elastic elements and said shock absorber 4 are subject to forces simultaneously and they act in cooperation, so as to produce a better shock absorption effect.
A Fourth Embodiment: Angled Arm Transmission Independent Suspension
[0063] This embodiment employs a manner of outputting by a right-angled output arm, and is shown in FIGS. 13, 14 and 15 .
[0064] The independent suspension of this embodiment comprises an upper fork arm 1 , a lower fork arm 2 , elastic elements 3 , a shock absorber 4 , fork arm positioning shafts 5 , right-angled output arm rotating shafts 11 , right-angled output arms 12 , and a linking arms 13 .
[0065] The upper fork arm 1 and the lower fork arm 2 are A-shaped structural elements. Front ends of the upper fork arm 1 and the lower fork arm 2 are respectively connected with an upper suspension point and a lower suspension point of a wheel C through main pins B, and rear ends of the upper fork arm 1 and lower fork arm 2 are connected to the vehicle frame by fork arm positioning shafts 5 respectively. Two connecting arms 13 are hinged on two sides of the front portion of the upper fork arm 1 respectively, and another ends of the connecting arms 13 are hinged to ends of two right-angled output arms 12 respectively. Other ends of the right-angled output arms 12 are connected with two elastic elements 3 , another ends of the elastic elements 3 are fixed to the vehicle frame. A right-angled output arm rotating shaft 11 is provided on the right-angled output arm 12 and pivotally connected to the vehicle frame. The shock absorber 4 is disposed between a front end of the upper fork arm 1 and the vehicle frame.
[0066] Each of opposite sides of a front portion of the lower fork arm 2 may also be hinged with a connecting arm 13 ; another end of the connecting arm 13 is hinged to an end of the right-angled output arm 12 ; another end of the right-angled output arm 12 is connected with an elastic element 3 ; another end of the elastic element 3 is fixed to the vehicle frame; and a right-angled output arm rotating shaft 11 provided on right-angled output arm 12 is pivotally connected to the vehicle frame, as shown in FIG. 16 .
[0067] The right-angled output arm 12 rotating around the right-angled output arm positioning shaft 11 is configured to change a vertical movement stroke of the front end of the upper fork arm 1 into a lateral movement stroke of the right-angled output arm 12 . The lateral movement stroke acts on two elastic elements 3 disposed symmetrically on the rear ends, so as to produce the effect of shock absorption. A shock absorber 4 is mounted on top of the front end of the upper fork arm 1 . In operation, the wheel C brings about upward bouncing of the suspension point of the wheel, the shock absorber 4 has a dampening effect. When the wheel C bounces up and down, the shock absorber 4 and the elastic elements 3 are subject to forces simultaneously and act in cooperation. Moreover, the upper fork arm 1 and lower fork arm 2 may each be provided with elastic elements, such that more hanging points may distribute the impact produced by bouncing of the wheel, so as to produce a better shock absorption effect.
A Fifth Embodiment: Torsion Spring Direct Transmission Independent Suspension
[0068] This embodiment employs a manner of twisting a torsion spring around an axle of a fork arm positioning shaft, and is shown in FIGS. 17, 18, 19 and 20 .
[0069] The independent suspension of this embodiment comprises an upper fork arm 1 , a lower fork arm 2 , fork arm positioning shafts 5 , torsional springs 14 , a shock absorber 4 and torsion spring seats 15 . The upper fork arm 1 and the lower fork arm 2 are A-shaped structural elements. Front ends of the upper fork arm 1 and the lower fork arm 2 are respectively connected with an upper suspension point and a lower suspension point of a wheel C through main pins B, and rear ends of the upper fork arm 1 and lower fork arm 2 are connected to the vehicle frame by torsional springs 14 and torsion spring seats 15 . The shock absorber 4 is mounted between top of the front end of the upper fork arm 1 and the vehicle frame.
[0070] Vertical bouncing of the wheel C brings about an upward movement of the front end of the upper fork arm 1 , and the upper fork arm 1 rotates about a rear fixing point, such that two torsion springs 14 arranged symmetrically on two sides produce a torsional deformation which has the effect of shock absorption. A shock absorber 4 is mounted on top of the front end of the upper fork arm 1 . In operation, the wheel C brings about upward bouncing of the suspension point of the wheel, the shock absorber 4 has a dampening effect. Said shock absorber 4 is mounted between the front end of the upper fork arm 1 and the vehicle frame. When the wheel bounces up and down, the shock absorber 4 and the torsional springs 14 are subject to forces on multiple points simultaneously and act in cooperation. Moreover, the upper and lower fork arms may each be provided with torsion springs, such that more hanging points may distribute the impact produced by bouncing of the wheel, so as to produce a better shock absorption effect. | An independent suspension comprises upper and lower fork arms, elastic elements, shock absorber and fork arm positioning pivots. The fork arms are A-shaped, front ends of the fork arms respectively connect to upper and lower suspension points of a wheel, and rear ends of the fork arms connect to a vehicle frame through the elastic elements. The shock absorber mounts on top of the front end of the upper fork arm. Vehicle frame bearing pivot points and transmission parts are constructed on peripheries of the upper and lower fork arms. The arrangement absorbs bearing elastic forces by changing directions of force and the arms of force, to form multiple points supporting multiple elastic elements, so force applied on the wheel is distributed by multiple points, increasing average running speed. Increasing the number and arrangement of the elastic elements reduces vehicle height, optimizes space utilization and improves stability and running smoothness. | 1 |
RELATED APPLICATIONS
This application is a continuation of U.S. application Ser. No. 14/125,984, filed Dec. 13, 2013 which is a national phase of PCT Application No. PCT/IL2012/000230, which was filed Jun. 13, 2012, which claims priority to U.S. Provisional Application 61/457,822, filed Jun. 13, 2011. Each of these applications is herein incorporated by reference in their entirety for all purposes.
FIELD OF THE INVENTION
The present invention relates to the field of distributed laser resonators using retroreflectors, especially for use in systems for wireless transmission of power to portable electronic devices by means of intracavity laser power.
BACKGROUND OF THE INVENTION
In the PCT application PCT/IL2006/001131, published as WO2007/036937 for “Directional Light Transmitter and Receiver” and in the PCT application PCT/IL2009/000010, published as WO/2009/008399 for “Wireless Laser Power” there are shown wireless power delivery systems based on distributed laser resonators. This term is used in the current disclosure to describe a laser having its cavity mirrors separated in free space, and without any specific predefined spatial relationship between the cavity mirrors, such that the laser is capable of operating between randomly positioned end reflectors. In the above mentioned applications, one use of such distributed laser resonators is in transmitting optical power from a centrally disposed transmitter to mobile receivers positioned remotely from the transmitter, with the end mirrors being positioned within the transmitter and receiver. Such distributed laser resonators use, as the end mirrors of the cavity, simple retro reflectors, such as corner cubes, and cats-eyes and arrays thereof. Retroreflectors differ from plane mirror reflectors in that they have a non-infinitesimal field of view. An electromagnetic wave front incident on a retroreflector within its field of view is reflected back along a direction parallel to but opposite in direction from the wave's source. The reflection takes place even if the angle of incidence of such a wave on the retroreflector has a value different from zero. This is unlike a plane mirror reflector, which reflects back along the incident path only if the mirror is exactly perpendicular to the wave front, having a zero angle of incidence.
Many of such generally available retroreflectors, 15 , such as that shown in FIG. 1 , generate an optical image inversion around an inversion point 10 situated in the retroreflector (or around points in the case of an array of retroreflectors), or in close proximity thereto, with the reflected beam 11 traversing a spatially different path to that of the incident beam 12 , as is shown in FIG. 1 .
This inversion around a point causes a number of problems in practical systems:
a. In many such simple retro reflectors, the inversion point is situated in an optically opaque location, where optical access cannot be provided, such as in a corner cube retroreflector. b. As will be further expounded in paragraphs (c) to (f) below, a distributed laser system designed for practical use should require the placing of optical elements within the cavity. However, this may be problematic, since, following paragraph (a) above, the inversion point in an optically opaque location results in two beams which do not overlap. The explanation for this is that a retro reflector does inversion around the point of inversion 10 in the beam's direction. Thus, expressing the beam directions in in cylindrical coordinates, Theta, the orientation angle, remains constant, R becomes minus R and the direction is reversed. For the two beams to overlap R must equal minus R which dictates that R equals 0, meaning that the reflection must take place at the opaque inversion point. As a result of this lack of overlap, as shown in FIG. 1 , placing a required optical element with at least one non-flat optical surface in the beam path will generally result in the two beams becoming unparallel, causing the distributed resonator to cease lasing. Such an optical component may cause each beam to be deflected differently, as is shown in FIG. 2 , which illustrates the behavior of two parallel beams, one, marked Beam 1 passing through the optical center 21 of a lens 20 , and one, marked Beam 2 , passing through a point 23 displaced from the center. As is observed, after passage through the lens 20 , the beams are no longer parallel. Since the two beams need to remain parallel for a distributed resonator to operate, as described in the aforementioned WO2007/036937 and WO/2009/008399, such an optical component cannot be used within a resonator having optical image inversion at its retroreflector(s) and having an opaque inversion point. Although it is possible to design certain optical elements to handle two parallel beams, such as a telescope lens arrangement, such a device may have a limited field of view and limited functionality, may require the separation between the beams to be fixed and may cause aberrations to both beams. This usually prevents the practical use of such telescope solutions. In U.S. Pat. No. 4,209,689 to G. J. Linford et al., for “Laser Secure Communications System”, there is described a distributed laser cavity for long range communication, with a telescope in the cavity close to the gain medium. This system deals with a beam which is very axially defined, and operates with as limited a field of view as possible, involving angles of propagation close to the axis. No mention is made of the longitudinal position of elements such as the gain medium, down the cavity length. It is believed that the telescope is used to expand the beam and hence to limit the beam divergence and field of view. In many other cases, there may not be need for a telescope, but rather for another optical element having a different function, such as a focusing lens, with the same problems arising therefrom because of the double beams. c. An optical system designed for two beams needs to use components generally having diameters of at least twice the size as those of equivalent single beam systems, in order to accommodate the two beams and the distance between them. This would increase the cost of the system, and its overall width. d. Usually, two simple retroreflectors are not enough to achieve lasing, since the beam typically needs to be focused in order to compensate for Rayleigh expansion. In the above referenced WO/2009/008399, this problem was solved by using a thermal focusing element. However such a solution suffers from increased complexity due to the need to initiate it. e. Optical elements having optical power, such as those having at least one non flat surface, may be necessary in the beam's path to achieve other optical functions, such as focusing, to correct aberrations, to monitor the system's state, to change the field of view of the system or to work with different apertures to allow for better performance/price of the system. Since the two beams are essentially separated, it may also be difficult to block ghost beams, as an increased aperture is needed. f. Since placing imaging optics inside the resonator is difficult, it is difficult to form an image of the position of a receiver. Such information may be potentially necessary to monitor a receiver or receivers connected to the transmitter.
An additional problem arises with the distributed laser systems shown in the above two referenced PCT publications, since the direction and position of the beams within the system are not known. It then becomes difficult to know where to place direction sensitive components in the beam's path, such as polarizers, waveplates, frequency doubling crystals, and the like, it also becomes difficult to know how to use position limited components, such as small detectors, gain media, and the like, since it is not known where to position such components laterally.
There therefore exists a need for a distributed laser cavity architecture which overcomes at least some of the above mentioned disadvantages of prior art systems and methods.
The disclosures of each of the publications mentioned in this section and in other sections of the specification, are hereby incorporated by reference, each in its entirety.
SUMMARY OF THE INVENTION
The present disclosure describes new exemplary systems and methods, for achieving distributed cavity laser operation using retro-reflecting elements, in which the spatially separated retro-reflecting elements define a power transmitting unit and a power receiving unit. The gain medium is advantageously placed in the transmitter unit, so that one transmitter can operate with several receivers, the receivers being of simpler and lighter construction. The described systems and methods overcome the double beam problems associated with use of simple retroreflectors in such prior art lasing systems. The described systems and methods also overcome the problems of defining the position, both laterally and longitudinally, of various optical components within the laser cavity, which provide ancillary advantages to the lasing properties of the cavity. There is therefore an advantage to a system which allows for some or all of the following characteristics:
a) Allows for retro reflection along the incident beam's path, so that the incoming and returning beams travel along the same path. This feature enables the distributed laser to operate with the beams in a co-linear mode, instead of the ring mode described in the prior art. b) Allows for elements with optical power, such as those with one or more non-fiat optical surfaces to be placed in the outgoing/returning beam, wherein these components might perform, inter alia:
Focusing/defocusing Increasing the field of view of the system Changing the Rayleigh length of the beam Adapting the beam to a specific operation distance.
c) Have regions in the system allowing placing of components so that light is always guaranteed to pass through the center of the component, so that component may be reduced in size and price, and increased in efficiency. d) Have regions in the system allowing the placing of optical components such that light is always guaranteed to be parallel to an optical axis. e) Have regions in the system where an image of the position of the receivers is formed, so that the receivers can be monitored. f) Have regions in the system where it is known that the laser beam cannot reach, so that functional elements sensitive to the laser beam but not required for the lasing action itself, may be placed there.
In order to achieve at least some of the above mentioned requirements, and to thereby provide a distributed cavity laser capable of operating with the features necessary for practical use of such a laser in the general environment, and with the necessary safeguards, there is proposed in this disclosure a distributed laser having a number of novel characteristics, as explained forthwith:
Firstly, use is made of cavity end mirrors based on retro-reflectors capable of reflecting a beam back onto itself, such that the incoming and returning beams from each retro-reflector essentially travel along coincident, but counter propagating paths. Some examples of such retroreflectors include conventional cat's eye retroreflectors for beams entering the cat's eye through the central region of its entrance aperture, focusing/defocusing cat's eye retroreflectors (including two hemispheres such that one hemisphere focuses light on the surface of the other, or more complicated structures having multiple elements in them, and still focusing), multi element (generalized) cat's eye retroreflectors, hologram retroreflectors, phase conjugate mirrors, and reflecting ball mirrors which are capable of reflecting a beam onto itself. In the case of the reflecting ball mirrors, although the beam would become defocused as a result of the reflection, this may be solved by use of a focusing element elsewhere along the beam's path.
However, such retro-reflectors may generate aberrations and other beam propagation problems such as focusing or defocusing, excitation of higher-order beams, or other artifacts, which need to be treated in order to ensure consistent quality lasing at acceptable power conversion efficiencies and within accepted safety standards. In addition, use of such retroreflectors may limit the field of view, which therefore may need to be increased optically to make the system of practical use. Additionally, components of the laser system might not have the optimum or the required size or field of view, which may be corrected using an additional optical system within the laser cavity. In order to overcome such effects, and to improve the performance of the overall laser system, it may be necessary or advantageous to add other optical components in the beam's path within the cavity, which operate so as to compensate for the undesired effect or effects. Using prior art distributed laser resonators having a double beam geometry, the insertion of additional optical components into the beam was ineffective because of this double beam geometry. However, this aim now becomes possible by the use of a single beam co-linear resonator, as described in the exemplary cavity structures of the present disclosure, instead of a two beam ring resonator.
Amongst the additional intra-cavity optical components or sub-systems which can be used, and the objectives which their use can achieve, are the following:
(a) A telescope may be used to increase the angular field of view of either the transmitter or the receiver units. (b) A telescope may be used to increase/decrease the Rayleigh length of the system, thus increasing operation range (for the case of increase of the Rayleigh length) or allowing selection of a single device from several that may be within range (for the case of decrease of the Rayleigh length). (c) A focusing system in either the transmitter unit or the receiver unit may be used to move the beam waist from the transmitter towards, or even right up to the receiver, thus reducing the size of the beam of at the receiver and hence the receiver's dimensions. (d) A lens, a grin lens, or a curved mirror system may be used to compensate for thermal lensing, or for compensating for other undesirable lensing effects in the system, such as when a ball mirror retro-reflector is used. (e) A polarizer may be used to define the polarization of the light propagating within the lasing system. (f) A waveplate may be used to:
(i) Define the polarization of the system (ii) Prevent unintentional lasing through transparent surfaces inserted into the beam and accidentally inclined at, or close to, the Brewster angle (iii) Prevent use of improvised and unauthorized receivers (iv) Increase the sensitivity of a safety system
(g) Optical elements may be used to correct aberrations caused by various component parts in the system. (h) The intra-cavity optical system may be used to enable a smaller gain medium to be used to amplify the light both in the forward direction and the backwards direction, allowing for increased gain and reduced size.
Further details of some of these components or sub-systems are given in the Detailed Description section herein below.
The existence of co-linear counter propagating beams has enabled the positioning of such optical components or subsystems within the laser cavity, enabling the achievement of the purposes described in the above paragraphs. This is a significant departure from prior art lasers, whether localized or distributed, where imaging or focusing functions are not generally incorporated within the laser cavity. The generation of focal points within a laser cavity is usually undesirable, since it can lead to hotspots on the coatings of optical components or on the components themselves or to plasma generation within the cavity. Usually there is no need for any components within the laser cavity, other than those essential for the lasing process itself, and attempts are generally made to avoid the inclusion of such additional components within the cavity in order to minimize optical losses, to simplify the system and to eliminate ghost beams. However in a distributed laser cavity for the type of application described in this disclosure, there is need for wide angle angular operation of the end mirrors of the cavity and the gain medium, since the transmitter and receiver units may be disposed at any position within the environmental range of the distributed laser cavity, and the laser must continue to function at its desired efficiency over a wide range of angles of incidence of the input and output beam of each end mirror. This requires an intra-cavity optical sub-system for handling the rays from different angles of incidence in such a manner that they do not detract from the lasing process.
In order to facilitate these aims, the exemplary distributed laser cavities described in the present disclosure advantageously utilize novel designs which involve the use of pupil imaging. Such a pupil imaging system can be defined as one in which light arriving from any incident angle and passing through the pupil, forms an image on a predefined image plane, the image position on this plane being dependent on the angle of incidence of the light passing through the pupil.
All of the light from each different angle of incidence, even if spatially spread out but arriving from a particular angle of incidence, will be transferred to the same spatial point on the image plane, on condition that all of the light from that angle passes through the pupil region. Light from different angles of incidence generates different spatial points on the image plane. The pupil itself can thus be defined based on these properties of the pupil imaging system. A graphic description of this concept is given in FIG. 3 in the Detailed Description section herein below.
Exemplary distributed cavity laser systems described in the present disclosure may be constructed having pupil imaging characteristics, thereby providing the following advantages to the system. Since the positioning of optical components or subsystems within the laser cavity is also an important criterion for ensuring a compact and readily designed lasing system, the optical imaging subsystem is also designed to allow placement of the various components in their optimal positions. There are several different criteria involved, depending on the purpose desired. In the first place, the system should be designed to have regions such that for components placed in that region, light from any angle of incidence is guaranteed to pass through the center of those components. This enables the reduction in the size of those components, thus decreasing cost and increasing efficiency. This can be achieved at the pupil or pupils of a pupil-equipped imaging system, and such a location or locations are therefore suitable for the positioning of such components as the gain medium of the lasing system, the photovoltaic power converting detectors, monitoring diodes, etc.
In practice, a pupil imaging system is defined by using a focusing element such as a lens, disposed at its focal distance from the desired position of the pupil. The above definition of the operation of a pupil based imaging system can be readily described in terms of the Fourier transform between angular and spatial information generated by passage of the beam through the lens. Using Fourier transform methodology a lens is described by the mathematical Fourier transform of angles into positions while the light travels the focal distance. In a simple single lens system, light emitted from the focal point of a lens at an angle to the axis, after passage through the lens, would be directed parallel to the optical axis of the lens at a distance from the axis that is dependent on the angle, thus loosing all angular information and exchanging it completely for spatial information. Reversing the direction of light, spatial information would be retranslated to angular information, so that at the pupil of the system, the beam would have no spatial information (as the pupil point is predefined) and only angular information.
When the lasing system is in operation, a laser beam would be formed between the center of the front pupil of the transmitter and the center of the front pupil of the receiver. When entering (or exiting) the transmitter, that beam would have only angular information, as it is passing through a known point. The optical system in the transmitter now images that front pupil onto an internal pupil plane where the gain medium may optimally be located. The beam passes through the center of the gain medium as that position provides an exact image of the front pupil of the system. Further along the beam's path, a lens positioned at its focal length from the internal pupil, transforms the angular information into spatial information. As soon as there is no angular information, a telecentric region is formed where components sensitive to angular information may be positioned.
In general, throughout this application, the functional effect of a pupil is understood to be achieved either by a real pupil, as implemented by the actual physical position in space through which the beam passes as it enters a lens, or by an image of a real pupil, as projected by imaging to another location in the system. References to a pupil, and claims reciting a pupil, are intended to cover both of these situations.
Applying the definition of a pupil imaging system from above to the distributed laser structures of the present disclosure, one immediate advantage is that when using a gain medium in the form of a thin disk located at the imaging plane of a pupil imaging system, light passing through the pupil from any direction will, after passage through the telescope system, always be centered on the disk of the gain medium at the secondary pupil relative to the output of the telescope. Therefore, a gain medium in the form of a thin disc, having its thickness substantially smaller than its lateral dimensions, will efficiently lase independently of the direction of incidence of the beam directed into the transmitter through the entrance pupil. Such use of a pupil imaging distributed laser system can optimally be implemented if the retroreflectors used in the system do not have a point of inversion, such that the incident beam is reflected back co-linearly from the retroreflector. This location of the gain medium relative to the elements of the pupil imaging system applies whether the imaging system is the input lens of the transmitter containing the gain medium, or the imaging system of the retro-reflector in front of which the gain medium is located. In either of these situations, the gain medium is located relative to the imaging elements such that light from any incident direction within the field of view will be focused onto the gain medium. Examples are given in the detailed description section of this disclosure as to how this is achieved in practice.
In addition, the system may be designed to have other regions, other than at pupil positions, at which beams coming from different angles will be optically directed to traverse those regions parallel to each other (i.e. telecentric regions), enabling the placement of optical components which should operate independently of the angle of incidence of the beam on the input lens.
Furthermore, the system should be designed to have regions where an image of the field of view of the system may be formed (imaging planes). Those regions are especially useful in placing such optical subsystems, for instance for generating an image of the position of the receivers.
Furthermore, the system should be designed to have regions where laser beam does not pass, so that components affected by the laser beam may be placed there. Such components might be detectors such as for monitoring the levels of such parameters as gain medium fluorescence level, thermal lens sensors, pump beam sensors for monitoring the level of the pump diode beams, either directly or through their effect in generating other wavelengths in the gain medium, and safety sensors.
One exemplary implementation of the systems described in this disclosure involves a distributed resonator laser system, comprising:
(i) first and second retro-reflectors, both of the retro-reflectors being such that a beam incident thereon is reflected back along a path essentially coincident with that of the incident beam, (ii) a gain medium disposed between the first and second retro-reflectors, (iii) an output coupler, disposed such that part of the beam impinging thereon is directed out of the resonator, (iv) a beam absorbing component disposed relative to the output coupler, such that that part of the beam directed out of the resonator impinges on the beam absorbing component, and (v) at least one optical component having at least one non-flat optical surface, disposed between the retro-reflectors, wherein the gain medium is essentially located at a pupil of the optical system incorporating the at least one optical component having at least one non-flat optical surface.
In the above described distributed resonator laser system, the beam absorbing component may be either a photovoltaic power converter or a heat transfer component. Additionally, the at least one optical component may be at least one lens disposed so as to define an entrance/exit pupil, such that light passing through the pupil at a plurality of different angles will be directed to the gain medium. Alternatively, the at least one optical component may be a mirror disposed so as to define an entrance/exit pupil such that light passing through the pupil at a plurality of different angles will be directed to the gain medium.
According to further exemplary implementations, such a system may further comprise a second lens disposed so that the beam is refracted thereby to generate a region of propagation parallel to the axis joining the center of the lens and the gain medium.
Additionally, the at least one optical component having at least one non-flat optical surface may be part of an optical system having an imaging plane. The gain medium may then be located at an imaged pupil of the entrance/exit pupil.
In any of the above described exemplary distributed resonator laser systems, at least one of the first and second retroreflectors should not have a point of inversion. Furthermore, the resonator should then support collinear beam modes. Furthermore, the optical system should have at least one imaging plane, and may have at least one telecentric region.
Additionally, the distributed resonator laser system may further comprise a sensor located at the pupil. The output coupler may be part of one of the retroreflectors, or it may be independent of the retroreflectors.
Additionally, alternative implementations of the distributed resonator laser systems described in this disclosure may comprise:
(i) a first retroreflector reflecting a beam incident thereon back along a path essentially coincident with that of the incident beam, (ii) a second retroreflector reflecting a beam incident thereon back along a path essentially coincident with that of the beam incident thereon, (iii) a gain medium disposed between the first and second retroreflectors, and (iv) a lens system disposed between the first and second retroreflectors, at a position such that the gain medium is situated at an imaging plane of the lens system.
In such a system, the lens system may further have an external pupil plane disposed at its end opposite to that of the gain medium, such that light passing through the external pupil from any direction will be directed towards the center of the gain medium at the internal pupil plane. In any of these systems, the system may include at least one telecentric region. Additionally, it may have at least one imaging plane. In such a case, it may then further comprise an optical sensor forming an electronic picture of the imaging plane. Additional components that may be incorporated into the system include a polarization manipulating optical component, doubling optics, and one or more waveplates located in the telecentric region. The system may further comprise a sensor located in the pupil.
The features and advantages described herein are not all-inclusive and, in particular, many additional features and advantages will be apparent to one of ordinary skill in the art in view of the drawings, specification, and claims. Moreover, it should be noted that the language used in the specification has been principally selected for readability and instructional purposes, and not to limit the scope of the inventive subject matter.
BRIEF DESCRIPTION OF THE DRAWINGS
The presently claimed invention will be understood and appreciated more fully from the following detailed description, taken in conjunction with the drawings in which:
FIG. 1 shows a representation of a prior art corner cube retro reflector generating an optical image inversion around a point situated in the retroreflector, with the reflected beam traversing a spatially different path to that of the incident beam;
FIG. 2 shows schematically the result of placing a lens in the beam path of a retroreflector such as that shown in FIG. 1 , having a point of optical inversion, resulting in spatially separated propagating beams;
FIG. 3 illustrates the manner in which pupils, or pupil planes and pupil imaging can be visualized, as used in the present disclosure;
FIG. 4A illustrates schematically a cat's eye retroreflector which can retroreflect a beam traversing its point of inversion;
FIG. 4B illustrates schematically a telecentric retroreflector using a flat reflector mirror;
FIG. 5 illustrates schematically a mirror ball retroreflecting a beam directed towards the center of the ball;
FIG. 6 illustrates schematically a distributed laser system according to one exemplary implementation of the novel structural features described in this disclosure, showing the location of the pupils of the system;
FIG. 7 illustrates schematically the distributed laser system of FIG. 6 , including further details of the components therein, and showing additional components of the lasing system;
FIG. 8 illustrates the display of a beam profiling unit for determining the presence of any perturbation to the propagating beam shape;
FIG. 9 illustrates how the telecentric region of the system may be generated using an auxiliary lens;
FIG. 10 illustrates schematically the manner in which the pupil imaging systems shown in FIGS. 6 and 7 incorporate a number of pupils;
FIG. 11 illustrates schematically the use of regions inaccessible to the beam for various monitoring functions, and
FIG. 12 illustrates schematically the use of mirror focusing in the transmitter, in place of the previously described lens focusing.
DETAILED DESCRIPTION
Reference is first made to FIG. 3 , which is provided to illustrate one way in which pupils, or pupil planes and pupil imaging can be visualized, in order to clarify graphically the explanations thereof given in the Summary section of this disclosure. In FIG. 3 , a lens 24 is positioned in space. All collimated beams passing through the pupil 25 form an image spot on the image plane 26 . For example collimated beam 27 will be focused on point 27 a on the imaging plane, while collimated beam 28 will form a focused image spot 28 a on imaging plane 26 .
If the system would be designed or set up to handle uncollimated beams with a certain radius of curvature, the imaging plane would move in space, but would still exist. The imaging plane is not necessarily flat. In this application the area in the vicinity of the pupil having a width essentially similar or slightly larger than the beam width, is termed “the pupil”, and the plane at which the beams are focused the “imaging plane”.
A telescope generally has an entrance pupil and an exit pupil, such that light beams passing through the entrance pupil would also pass through the exit pupil. The two pupils are positioned in space such that one pupil is an optical image of the other.
Reference is now made to FIG. 4A , which illustrates schematically a conventional cat's eye retroreflector configuration 30 which can retroreflect a beam back along its incident path, on condition that it passes through the point of inversion 31 , which in FIG. 4A is situated at the center of the lens 32 . In such a retroreflector, a concave mirror 33 is disposed at the focal plane of the entrance lens 32 , or more accurately, at the focal distance from the entrance lens, such that a beam incident at any angle of incidence is focused by the entrance lens onto the concave mirror surface, each angle of incidence being focused at a different spatial position on the mirror. To illustrate the importance of the point of inversion, two incident beams are shown in FIG. 4A . The beam 35 coming from the top left-hand region of the drawing, passes through the point of inversion 31 at the center of the lens, impinges on the reflector mirror 33 at a normal angle of incidence, and is reflected back along its own incident path. On the other hand, the beam 36 coming from the bottom left hand side of the drawing, passing through the lens at a location away from the point of inversion, impinges on the mirror 33 at an angle of incidence other than zero, and is reflected back on a path 37 which is parallel to, but not coincident with, the incident path. Since rays of light from any incident angle, passing through the point of inversion at the center of the lens, are retroreflected back along their own path, this position represents the pupil of the optical system of the cat's-eye, and this point would be the ideal position for locating the gain medium of the laser cavity. However, the use of this simple cat's eye retroreflector is limited since the pupil is situated at the center of the lens, and it is thus difficult to locate the gain medium there, unless the gain medium also acts as a lens, such as by shaping it as a lens or by using the thermal lensing properties generated by the gain medium during lasing.
Reference is therefore made to FIG. 4B which illustrates schematically a telecentric retroreflector 40 which overcomes the problem of the inaccessibility of the pupil in the retroreflector of FIG. 4A . The reflection mirror in this case is a flat mirror 43 , and as in FIG. 4A , it is located at the focal distance from the lens 42 . A pupil, as marked pupil region 44 in FIG. 4 , can now be defined at a distance equal to the focal length on the input side of the lens, such that any incident ray passing through the center of the pupil will be focused normally at a position on the reflector mirror in accordance with its angle of incidence, and will be reflected back along its incident path through the center of the pupil. Two such rays 45 , 46 , coming from different angles of incidence are shown in FIG. 4B . However, unlike the device shown in FIG. 4A , the pupil plane 47 is now physically situated outside of the focusing lens, such that optical components, such as the gain medium, or the photovoltaic converter (assuming it would be only partially absorbing), an iris to block ghost beams or an output coupler, can be positioned at such a pupil without any physical limitation.
An alternative to the above types of cat's eye retroreflectors, are retroreflectors having no point of inversion, but still capable of retroreflecting a beam onto itself. One such example is a mirror ball 50 , as shown schematically in FIG. 5 . A mirror ball would retroreflect and defocus a beam directed towards the center of the ball 51 , as shown by the beam 52 entering the ball mirror vertically, while beams not directed towards the center of the ball mirror, as shown by the beam 53 entering the ball horizontally, are not retroreflected but are reflected off the ball in some other direction and defocused in the procedure.
Reference now is being made FIG. 6 , which illustrates schematically a distributed laser system according to one exemplary implementation of the novel structural features described in this disclosure, such as could be used for distributing optical power from a transmitting power source to remote receivers, which can use the lasing power to operate a portable electronic device or to charge its battery. One characteristic feature of the optical design of such distributed laser systems is the positioning of pupils within the system at locations which enable advantageous positioning of components or elements of the lasing system which should have small lateral dimensions. Thus for instance, the gain medium is placed at pupil 54 , which is a common pupil for the internal retro-reflector 55 and for the internal end of the telescope 78 , to which it behaves as the internal pupil. The telescope also has an external pupil at its outer side, which is the exit entrance pupil 57 of the transmitter and is coincident with the plane of the optical image of the internal pupil 54 , where the gain medium is located. From the exit/entrance transmitter pupil 57 the lasing light propagates essentially collimated towards the center of the receiver entrance/exit pupil 58 and is reflected from the receiver 59 back through this pupil. Since the light between the two entrance/exit pupils ( 57 and 58 ) is essentially collimated, the two pupils 57 and 58 are essentially optical equivalents of each other. The receiver and transmitter may have other internal pupils (by means of imaging of the above pupils) where optical components may be placed. In that respect, each of the system's pupils are essentially located at image planes of other system pupils. The telescope shown in the embodiment of FIG. 6 typically uses lenses in its optical system, but it is to be understood that any other optical system which has pupils at the desired locations in the resonator, such that components such as the gain medium can be positioned thereat, can also be used. An exemplary system using mirrors is shown in FIG. 12 herein below.
Reference is now made to FIG. 7 , which illustrates schematically a rendering of the distributed laser system shown schematically in FIG. 6 , but showing more of the details of the specific elements of the laser. The transmitter 60 , situated in the top half of the drawing, containing the gain medium 61 of the laser and the lens 63 and rear mirror 62 , form together a telecentric cat's eye retroreflector capable of retroreflecting the lasing beam back onto itself, such as any of the types described hereinabove. The gain medium may advantageously be Nd:YAG, lasing at 1064 nm. The receiver 65 is situated in the bottom part of the drawing, and contains the output coupler 66 which should also be part of a retroreflector reflecting the laser beam back onto itself. These three components, namely the back retroreflector (composed of the lens 63 and the back mirror 62 ), the gain medium 61 , and the output coupler retroreflector (composed of the output coupler 66 and the lens 68 ) thus constitute the basic lasing system. Their relative location with respect to additional components used in the system is an important element of the novelty of the presently described system. The “intra cavity” beam propagates between the two cavity mirrors 62 , 66 in free space 64 , which is the transmission path of the lasing beam feeding optical energy from the transmitter 60 to the receiver 65 . As described in relation to FIG. 6 , the telescope 78 has two pupils, an internal (relative to the transmitter) pupil of the telescope located at, or very close to the gain medium 61 and an external (exit) pupil located on the other side of the telescope, towards the free space propagation region 64 . Besides these pupils external to the telescope itself, there may also be an internal pupil or a telecentric region of the telescope, which may be useful for placing other components.
In the exemplary implementation shown in FIG. 7 , the rear mirror 62 of the transmitter comprises a flat reflector located at the focal distance of a lens 63 , in the same configuration as that shown in FIG. 4B . The gain medium 61 is positioned at the common pupil of both this retroreflector and the internal pupil of the telescope 78 , such that light entering through the telescope would be directed towards the gain medium, and then towards the retroreflector, and back. A mirror 67 at the rear of the gain medium 61 reflects the beam towards the back retroreflector 62 , such that the beam passes twice through the gain medium in each pass through the laser. However it is to be understood that the system is not meant to be limited to this configuration, and that the gain medium could also have a pure transmission configuration, without the mirror 67 , and with the retroreflector linearly located behind the gain medium 61 .
The retroreflector of the receiver 65 of this implementation comprises the output coupler 66 , such as a partially reflecting mirror, with a lens 68 located at its focal distance from the output coupler. This combination comprises a cat's eye retroreflector which ensures that that part of the beam which passes through the inversion point at the center of the pupil, which is physically located at the center of the lens 68 , is reflected back along its incident path. The nature of the laser cavity is such that, when possible, the central part of the beam passing through the pupil would undergo efficient lasing, while other directed beams would not, such that the central part of the beam develops at the expense of other directed parts of the beam. The center of the lens 68 is a pupil of the receiver, such that the receiver, like the transmitter, operates independently of the angle of incidence of the input beam (as long as that passes through the pupil). That part of the beam which passes through the output coupler is again focused by another lens 69 onto the photovoltaic cell 70 which converts the optical power of the laser beam to electricity. This photovoltaic cell is situated at another pupil, the focal length away from the lens 69 , such that it can be a small photodiode. Prior art distributed cavity lasers, without the focusing facility enabled by the present implementation, would require a photovoltaic cell of much larger lateral dimensions.
The above description constitutes one possible combination of building blocks of a system exemplary of the type described in this disclosure. The transmitter may also have a number of other features, beyond this structure, and these are also shown in FIG. 7 . The transmitter 60 may further comprise a beam blocking aperture 80 disposed at its entrance/exit pupil 57 , blocking most of the ghost beams reflected from the optical surfaces. Elimination of such ghost reflections increases the safety of the system. The receiver 65 may likewise have an entrance pupil 58 with a beam blocker (not shown) for the same purpose. A lens at the entrance to the receiver is required in order to relay the position of the internal pupil to the external beam blocker plane. Achieving such an image of the internal pupil may also be achieved by many optical designs.
The back mirror 62 in the transmitter may be partially reflecting, allowing a back leak beam to pass through for monitoring purposes. A beam splitter 71 allows part of the beam to pass through for monitoring the position of receivers which are lasing in conjunction with the transmitter. This sensing device 72 could be in the form of a simple CCD camera, or a quadrant detector or any similar position sensing device. Use of simple algorithmic position detection routines enables the number of receivers to be counted, and their approximate angular positions to be determined.
Another part of the back leak beam may optionally be used for inspecting the beam profile, in order to determine the presence of any perturbation to the beam shape. With a cat's eye configuration, the leaked beam is the Fourier transform of the beam's shape at the pupils. In order to inspect the profile of the beam itself, it is necessary to use a lens 75 to image the pupil(s) onto a plane where a beam profiler 74 could be positioned. This is used as a safety feature for determining when an obstruction, such as a part of the user's body, has entered the beam path. Reference is now made to FIG. 8 which illustrates this facility. So long as the beam is unobstructed, the beam profile has a generally circular shape 76 , as determined by the beam profiler 74 . When even a small obstruction enters the beam from any position, it will cause such a significant degradation in the laser mode that the profile of the output beam will be perturbed by a factor many times larger than the size of the physical perturbation of the obstruction. In the example shown in FIG. 8 , a small obstruction has entered the beam at a point horizontal (as defined by the drawing orientation) to the beam, and this has resulted in the generation of a distinctly oval beam profile 77 , which can be readily detected by the beam profiler 74 . Image processing algorithms can then be used to generate a warning or a shutdown signal to the laser system in order to avoid potential damage to the user who has caused the perturbation by entry into the beam.
The telescope 78 of FIG. 7 may be used to increase the field of view of the transmitter. In addition a polarizer may be placed in a telecentric region in order to define the polarization of the light generated by the laser. The definition of the polarization direction of the lasing beam can be used to prevent lasing through a transparent surface inserted into the beam unintentionally and accidentally aligned at the Brewster angle to the beam. If the laser beam was unpolarized, although the likelihood of a transparent surface being inserted at the Brewster angle is low, it is still an existent danger. However if in addition to the Brewster angle, the transparent surface must be aligned such that the polarization direction of the beam allows the Brewster angle to function as a reflector with the predetermined polarization, the likelihood of this happening is infinitesimally small, thereby increasing the safety of the system. Alternatively a quarter wave plate may be added in the transmitter and or in the receiver at a telemetric region, causing the beam polarization to be circular or unpolarized, therefore eliminating the Brewster angle reflection risk altogether. As an alternative implementation, the polarization direction can be used for coding specific receivers, each polarization direction connecting the transmitter with a specific receiver.
An additional focusing lens 79 may be included in the transmitter 60 , in order to make small compensation changes to the Rayleigh length of the system.
Reference is now made to FIG. 9 , which illustrates how the telecentric region of the system may be generated. In a similar manner to the planar mirror cat's eye retroreflector illustrated in FIG. 4B , if a lens 80 is located at its focal distance from a pupil 81 of the system, it will refract the beam in a direction parallel to the axis in its passage towards the imaging plane 82 . The imaging plane 82 could be the planar rear mirror of the distributed laser cavity, or any other plane. The region where the beam propagates parallel to the axis is the telecentric region, where it is possible to locate any optical components whose performance is dependent on the direction of the light traversing it. Beams coming through the pupil location at different angles will be refracted in paths laterally displaced from that shown in FIG. 9 , but parallel thereto, such that the direction sensitive component will optically handle all of those beams in the same way. Although the configuration of FIG. 9 shows the telecentric region as being parallel to the optical axis of the system, if the pupil is offset from that optical axis, the beams in the telecentric region will at an angle to the optical axis, but will still be parallel to each other, such that they will be optically handled in an identical manner by any directionally sensitive optical component. Such components could include frequency multipliers using optically active crystals, polarizers, any type of wave plate, interference filters, or even additional lasing components associated with a separate laser system.
Reference is now made to FIG. 10 which illustrates schematically the manner in which the pupil imaging systems shown in FIGS. 6 and 7 incorporate a number of pupils, and the functions of each of the pupils. The receivers Rx1 and Rx2 each have an entrance pupil 101 , 102 , at their front aperture, the function of these pupils being to ensure that incoming beams from any direction are directed into the receiver retro reflector. The iris 103 at the outer aperture of the transmitter Tx is located at an entrance/exit pupil, ensuring that light beams passing through the iris 103 from any external angle are directed into the telescope 106 such that, after traversing the lenses of the telescope, they are focused onto the back pupil of the telescope, where the gain medium 104 is disposed. The same arrangement is of course applicable for light emitted from the gain medium and passing through the telescope out of the transmitter. The pupil location of the gain medium then also acts as a pupil plane for the internal retroreflector 105 of the transmitter Tx. This drawing thus illustrates how the lasing beam passes through a number of sequentially located pupils, defining planes in which externally propagated beams from any angle within the operating field of view of the system are focused into regions of small lateral dimensions, suitable for placement of such components as the gain medium 104 , the photovoltaic detector 70 , and the input/exit apertures 101 , 102 , 103 of the receivers or the transmitter respectively.
Reference is now made to FIG. 11 which illustrates schematically the use of regions inaccessible to the beam for various monitoring functions. One such region has already been shown in FIG. 7 and FIG. 8 , where part of the back leak beam from the rear mirror 62 of the cavity is use to monitor the beam shape 76 , 77 . In addition, there are regions within the transmitter where it is possible to position beam detectors for monitoring functions of the lasing beam, such as photodiodes, even though the detectors themselves are not in the beam path or any selected part of it. The detectors can, for instance, view the gain medium and monitor lasing performance by changes observed therein. Some such locations are shown schematically in FIG. 11 , where the various components are labeled as in FIG. 7 . Thus, in locations 111 , 112 and 113 , a sensitive detector can monitor conditions in the gain medium without fear that the beam will impinge upon and damage the detector. Thus for instance, a detector viewing the power level of the fluorescent emission of the gain medium at a wavelength different from the lasing beam would instantly detect any change in beam power arising from the obstruction of part of the external beam path by an object, such as a person's body part, and the monitor signal could be used for momentarily shutting down the laser to avoid damage to the intruding body part. As another exemplary use, the detector could incorporate a filter for viewing a secondary laser emission from the gain medium at a different wavelength, such as may arise when the pump power changes due to pump diode heating, and the monitor signal is used to correct the pump diode temperature or current to restore correct lasing conditions. A thermal lensing sensor may also be used in such locations.
All of the above described implementations of the present systems have been shown using lenses for focusing the laser beam. Reference is now made to FIG. 12 which illustrates schematically a distributed laser system, in which mirrors are used instead of lenses in order to define entrance and exit pupils, such that light passing through the pupil at a plurality of different angles will be directed to the gain medium. In FIG. 12 , the beam retro reflected from the receiver 120 to the transmitter 121 is focused by means of a telescope system comprising a pair of mirrors 123 , 123 , which direct the lasing beam onto the gain medium 125 . The gain medium 125 is optimally located at a pupil of the internal end of the double mirror telescope.
The foregoing description of the embodiments of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Many modifications and variations are possible in light of this disclosure. It is intended that the scope of the invention be limited not by this detailed description, but rather by the claims appended hereto. | A distributed resonator laser system using retro-reflecting elements, in which spatially separated retroreflecting elements define respectively a power transmitting and a power receiving unit. The retroreflectors have no point of inversion, so that an incident beam is reflected back along a path essentially coincident with that of the incident beam. This enables the distributed laser to operate with the beams in a co-linear mode, instead of the ring mode described in the prior art. This feature allows the simple inclusion of elements having optical power within the distributed cavity, enabling such functions as focusing/defocusing, increasing the field of view of the system, and changing the Rayleigh length of the beam. The optical system can advantageously be constructed as a pupil imaging system, with the advantage that optical components, such as the gain medium or a photo-voltaic converter, can be positioned at such a pupil without physical limitations. | 7 |
BACKGROUND
1. Field of Invention
This invention relates to a fuel activating device and method consisting of at least two separate infrared-emitting bodies, each infrared-emitting body being engineered to have specific peak wavelength and spectral luminance in 3-20 um (micrometer) wavelength range, that provides an effective means for enhancing combustion of hydrocarbon fuels in internal combustion engines, resulting in better engine performance with increased power, improved fuel economy, and reduced emissions.
2. Description of Prior Art
According to Organic Chemistry, photoexciting hydrocarbons with infrared photons shorter than 20 um in wavelengths for enhanced fuel conversion efficiency were believed to be scientifically predictable. After years of research the present inventor had discovered the use of infrared radiation at 3-14 um wavelengths, which are categorized as “mid-infrared” by U.S. NASA but as “far-infrared” in Japanese convention, for improving combustion efficiency of hydrocarbon fuel in internal combustion engines that resulted in inventions of fuel combustion enhancement devices as disclosed in U.S. Pat. Nos. 6,026,788 and 6,082,339 by the present inventor. Since then, a number of inventions in this field followed, for example U.S. Pat. Nos. 7,021,297, 7,036,492, and 7,281,526 just to name a few.
Although the device as described in U.S. Pat. No. 6,026,788 by the present inventor worked adequately, the fuel activation effect became limited in the applications for heavy duty gasoline or diesel trucks due to the fact that these applications required irradiating a large flow of fuel substance in a very short time interval. Besides, commercial fuels comprise a very complex hydrocarbon system that contains a wide variety of hydrocarbons and absorb infrared photons all over the entire 3-20 um wavelength spectrum.
In Organic Chemistry, hydrocarbons absorb assorted infrared photons in 3-20 um wavelengths causing molecular vibrations. The present inventor has experimentally verified in laboratory that increasing molecular vibrations can result in lowered activation barrier of hydrocarbon molecules and thus increase fuel's combustibility with amplified oxidation rate in combustion. However, as stated before, the multiple-component hydrocarbons in commercial fuel systems require absorbing photons with wavelengths spanning all through the 3-20 um wavelength range so that it requires uniform emissions over the said spectrum to effectively excite all hydrocarbon components in the fuel systems.
Unfortunately, regardless of endless trials, the present inventor found it would be difficult to design a broadband infrared emitter that could uniformly distribute the radiation energy over the entire 3-20 um spectrum. In theory, most of the available radiation energy from such IR-emitter is often associated with short wavelengths (i.e. high frequencies). Moreover, the peak wavelength where the maximum flux density per unit wavelength interval emerging from IR-emitter will displace toward short wavelength as temperature increases, known as Wien's Displacement Law. This inevitably results in radiation energy being over-strengthened in short wavelengths but weakened in long wavelengths, which may leave some groups of hydrocarbons in the fuel unexcited or less-excited and reduce the overall infrared activation effect on the fuel.
The devices as described in U.S. Pat. No. 6,026,788 by the present inventor used an infrared emitting body composed of metal oxides selected from the groups consisting alumina, silica, zirconia, lithium oxide, magnesium oxide, calcium oxide, titanium oxide, and so on. After the mixture of purposely selected oxides and bonding agent had been sintered at a temperature above 1200° C., the characteristic infrared spectral luminance became specific and permanent. The profile of spectral radiation rate of such IR-emitter can be preset only by carefully choosing the composition of oxides and processing parameters during fabrication. As such, IR-emitters with specific peak wavelength and spectral luminance profile in the desired 3-20 um wavelength range can be deliberately made.
Accordingly, the present inventor had tailored IR-emissions at specific peak wavelengths in 3-20 um range by precisely controlling weight percentages of key elements such as zirconia, magnesium oxide, and cobalt oxide in the oxide mixture. In laboratory, the peak wavelengths of IR-emitters containing various amounts of cobalt oxide (CoO), magnesium oxide (MgO), and zirconia (ZrO 2 ) have been experimentally determined to be around 3 um, 5 um, and 10 um, respectively.
In addition, the present inventor also experimentally discovered that purposely using at least two IR-emitters with various peak wavelengths in a group could significantly increase the fuel activation effect on fuel, and thus dramatically improve engine performance.
As described above, the prior art failed to teach the combined use of a number of IR-emitters with specific peak wavelength and spectral luminance in 3-20 um wavelength range for maximizing improvement of hydrocarbon fuel combustion efficiency in engines.
Objects and Advantages
Accordingly, one object of this invention is to provide a device that can effectively increase combustion efficiency of hydrocarbon fuels in an internal combustion engine to enhance its performance for increased power, improved fuel economy, and reduced emissions.
Another object of the present invention is to provide a simple, easy-to-install, and maintenance-free fuel combustion efficiency enhancement device.
These objectives are achieved by an infrared fuel activation device comprising essentially at least two infrared emitting bodies, each with a specific peak wavelength and spectral luminance. The device can be mounted on the exterior or disposed in the interior of a fuel line of an engine to excite the hydrocarbon fuel before it enters the cylinders for combustion.
Other objects, features and advantages of the present invention will hereinafter become apparent to those skilled in the art from the following description.
DRAWING FIGURES
FIG. 1 shows a perspective view of one embodiment of the present invention with two separate infrared emitting bodies in partial-tubular form being mounted on a fuel line.
REFERENCE NUMERALS IN DRAWINGS
11 Infrared emitting body 1
12 Infrared emitting body 2
21 Attachment means
22 Fuel line
SUMMARY
In accordance with the present invention a fuel activating device and method consists of at least two infrared emitting bodies, each body being made of selective metal oxides to have specific peak wavelength and spectral luminance in 3-20 um wavelength spectrum. It can enhance fuel efficiency of internal combustion engines, resulting in better engine performance with increased power, improved fuel economy, and reduced emissions. The fuel activation device can be either mounted on the exterior or disposed in the interior of a fuel line of an engine to energize the fuel before it enters the cylinders for efficient combustion.
DETAILED DESCRIPTION OF THE INVENTION
It is well known that absorption of an infrared photon at a wavelength shorter than 20 um (micrometer) gives rise to bond stretching or bending vibration in hydrocarbon molecule. In fact, Organic Chemists have been using IR absorption spectral analysis (so-called “Infrared Correlation Charts”) to identify unknown specimen for decades. Based on spectral absorption profile in 3-7 um (so-called “Functional Group” zone) and 7-20 um (“Signature” Zone) ranges the test specimen can be precisely identified. However, what people had long ignored was absorbing IR photons could increase kinetic energy of covalent bonds and thus cause molecule to vibrate. It not only changes dipole moment of hydrocarbon molecule, but also decreases activation barrier of the bond and increases reaction rate during combustion, as described in Quantum Mechanics.
The present inventor had reported favorable results on using the devices as described in U.S. Pat. No. 6,026,788 to excite fuel for enhanced engine performance. The net results were improved fuel combustion efficiency with increased torque/power, reduced fuel consumption, and lowered emissions. Nevertheless, the present inventor faced a limitation using such an IR Fuel Activator in heavy duty gasoline or diesel truck applications that require exciting a much larger flow of fuel substance instantly. After years of research, the present inventor had realized the use of a well-balanced infrared spectral luminance all through 3-20 um spectrum would be required for exciting all hydrocarbons in the fuels for such applications.
The present inventor further learned in literature search and confirmed in experiments that the peak wavelengths of cobalt oxide, magnesium oxide, and zirconia are around 3 um, 5 um and 10 um, respectively. Adding various weight percentages of such oxides to the oxide mixture as disclosed in U.S. Pat. No. 6,026,788 provides a means to manipulate peak wavelength and spectral luminance of the resultant IR-emitter.
In addition, the present inventor also found the pyroelectric property of tourmaline, one of the most complicated silicate minerals, could help increase thermal conversion efficiency of IR-emitter. Therefore, substituting a part of silicate with tourmaline in forming the IR-emitting body can significantly improve its overall infrared emissions in 3-20 um wavelength range. Several examples of the present invention were prepared accordingly for concept-demonstrating experiments.
FIG. 1 shows a perspective view of one embodiment of the present invention, in which two infrared emitting bodies, 11 and 12 , are mounted on a fuel line, 22 , of an engine. The two infrared emitting bodies may be secured with an attachment means, 21 , to the fuel line. In this case it is a wrap tie. The infrared emitting body can take any shapes, forms, styles, patterns, and in any thickness, though partial-tubular shape is preferred for the ease of placing on the exterior of a fuel line in this embodiment.
In other embodiments the infrared emitting bodies can be disposed in the interior of a fuel line, embedded or coated on the inner wall, or being a part of the fuel line.
EXAMPLES
Three (3) infrared-emitting bodies were designed and devised for demonstration: Sample A contains 31 wt (weight) % silicate, 16% alumina, 39% ferric oxide, 5% chromic oxide, 4% cobalt oxide, and others; Sample B 41% silicate, 27% alumina, 15% zirconia, 9% magnesium oxide, 2% cobalt oxide and others; and Sample C 43% silicate, 19% alumina, 28% zirconia, 5% sodium monoxide, 3% potassium oxide and others. An SEM/EDS (scanning electron microscope with energy dispersive spectrometry) plot was run with each sample to obtain a quantitative analysis on the elemental composition of the oxide compounds. In lab, an infrared imaging camera with variable wavelength band filters was used to determine the spectral luminance for each IR-emitter. Combined use of two or three of these IR-emitters was proved to outperform the use of same number of IR-emitters of the same kind.
Scientific Verification Experimentation
The effect of the combined use of different IR-emitting bodies having specific spectral luminance was scientifically investigated in a Methane-Air Counter-flow Non-premix Laminar Diffusion Flame experiment. Counter-flow laminar flames are widely used in evaluation of chemical kinetic rates because they are one-dimensional and have a uniform strain rate. Counter-flow flames also allow the use of OPPDIF code to reveal chemical kinetics details with manageable computational times. Besides, the methane mechanism and the well-established thermochemical database can be used to predict and compare the measured concentrations of major species, such as CH 4 , CO, CO 2 , H 2 , C 2 H 2 , C 2 H 4 , and NO.
The study had successfully demonstrated the IR-effect on influencing flame structure (i.e. distribution of species across the flame) with reduced pollutant (CO and NO) emissions. The fuel consumption rate was reduced by 8% with the IR-excitation from said IR-emitters working as a group. The data showed IR-excited methane produced 25% less peak CO and CO 2 emissions than regular methane. Meanwhile, the NO emission index for combustion of IR-excited methane is computed to be about 15% less than regular methane.
Beta-Site Vehicle Testing
The combined use of IR-emitters were tested by a voluntary trucking company at Indianapolis (Ind.) on their 2005 Kenworth T600A truck-trailers equipped with a 15 L Cummins ISX-475 heavy duty diesel engine. Four trucks participated in the test for 3 months. The results indicated a respective fuel economy improvement of 13.9%, 10.5%, and 11.0% for the three trucks with IR-emitters installed, while the fuel economy for the fourth truck, serving as a Control Truck with no IR-emitters installed, remained nearly unchanged.
Conclusion, Ramifications, and Scope
According to the present invention, an IR Fuel Activation device comprises at least two infrared emitting bodies, formed of separate compositions of IR emitting materials and thus emitting infrared at distinct peak wavelengths with specific spectral luminance in 3-20 um range, that can be either mounted on the exterior or disposed in the interior of a fuel line of an internal combustion engine for increased fuel combustion efficiency and improved engine performance.
The invention has been described above. Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. Such variations are not to be regarded as a departure from the spirit and scope of the invention and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims. | This invention relates to a fuel activating device and method consisting of at least two separate infrared-emitting bodies, each infrared-emitting body being engineered to have specific peak wavelength and spectral luminance in 3-20 um (micrometer) wavelength range, that provides an effective means for enhancing combustion of hydrocarbon fuels in internal combustion engines, resulting in better engine performance with increased power, improved fuel economy, and reduced emissions. | 5 |
This invention relates to a process for the synthesis of imidazole carbenes and the use thereof for the synthesis of ionic liquids.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the apparatus for the synthesis of imidazolium carbenes.
DETAILED DESCRIPTION
Carbenes are generally organic molecules which have a lone pair of electrons on a carbon atom and which in turn renders them highly reactive. As a result, carbenes are highly reactive intermediates in the synthesis of chemical compounds. Carbenes, due to their highly reactive nature, are generally only isolatable in the form of eg metal carbenoid species.
Numerous methods for the generation of imidazole carbenes have been reported. Starting from an imidazolium halide, the use of systems such as sodium hydride in ammonia or dimethyl sulfoxide (DMSO), sodium in ammonia, alkali metals in tetrahydrofuran (THF), metal t-butoxides in THF or DMSO, etc. These suffer from the disadvantage that very dry conditions and reagents have to be used, difficult separations under strictly anhydrous conditions are involved, and the reagents used can be expensive and inconvenient.
We have developed a simple procedure for the generation of the imidazolium carbene in 90-95% yield from an imidazolium chloride: this does not require solvents, filtrations, or lead to the production of noxious waste products.
According to the first aspect of the present invention, there is provided a process for the preparation of imidazolium carbenes of formula (I),
wherein R 1 and R 2 , which can be the same or different, are hydrogen or linear or branched hydrocarbyl groups,
comprising heating an imidazolium halide with a strong base under reduced pressure and separating the resultant products.
The process is preferably carried out under vacuum. The resultant products can be separated using any known separation techniques such as distillation.
The imidazolium halide may suitably be a chloride, bromide or an iodide and is preferably a chloride. R 1 and R 2 are suitably alkyl, alkaryl, aryl or aralkyl groups, more preferably alkyl groups. These hydrocarbyl groups suitably have from 1-20 carbon atoms, preferably from 1-8 carbon atoms. Specifically these substituents may be methyl or ethyl groups.
The strong base heated with the imidazolium halide may be any of the conventionally known strong bases such as eg alkali metal alkoxides, sodium hydride, sodium amide (NaNH 2 ) and the like. The strong base is suitably an alkali metal alkoxide in which the alkoxide group has 1-4 carbon atoms and may be a straight or branched chain. Specific examples of these are the methoxide, the ethoxide, the propoxide and the butoxide, especially the tertiary butoxide. Of the alkali metals in the alkoxide, potassium is preferred.
In one embodiment of the present invention, the process involves the distillation under vacuum of the carbene from a mixture of an imidazolium chloride and a commercially available metal alkoxide such as eg potassium t-butoxide The commercial metal alkoxide need not be further purified before use. The by-products of this reaction, where an imidazolium chloride is heated with potassium t-butoxide, are potassium chloride and t-butanol (which can be recycled). The method is straightforward, relatively cheap, and does not involve the production of noxious waste products.
Two examples of the reaction are shown below in which the substituents on the imidazolium groups are represented by the following abbreviations:
Et—Ethyl
Bu—Butyl
Me—Methyl
Bu t —Tertiary butyl
KOBu t —Potassium tertiary butoxide
HOBu t —Tertiary butanol
The two carbenes shown, which fume in moist air, are both colourless oils with a characteristic smell (freshly mown grass), of boiling point 90° C. and 130° C. at about 130 Pa (1 mm Hg) pressure, respectively. They appear to be thermally stable up to 200° C. for short periods of time, and stable at room temperature for several days (the mode of decomposition appears to be water-promoted disproportionation to a 2H-imidazoline and an oxidised species). However, they are extremely hygroscopic, reacting with moisture in the air to form the corresponding imidazolium hydroxide, itself being a novel ionic liquid. Consequently, they must be handled under dinitrogen or in an inert atmosphere glove box. The reaction of forming carbene itself is carried out in the substantial absence of any solvents. However, once produced, to facilitate handling of the carbenes, it may be dissolved in solvents. Suitable solvents for the dissolution of carbenes are limited, but aromatic, aliphatic (alkanes) and ether solvents appear to be appropriate. Halogenated and ketonic solvents must not be used, especially carbon tetrachloride, chloroform and primary alkyl halides, owing to a rapid exothermic transformation.
These carbenes can be used for conversion thereof to the corresponding imidazolium salts by a simple reaction with the acid form of the required anion. This reaction takes place according to the following equation;
wherein R 1 and R 2 are as hereinbefore defined.
Thus, the present process can be used to generate imidazolium salts with a variety of anions such as those graphically represented in the equation below:
As can be seen from the above, the acid form of the anion can be any one of a vast variety of compounds including inter alia alcohols such as eg methanol or propanol, and acids such as eg carbonic acid, acetic acid or alkyl sulfonic acid.
Imidazolium salts of this type are essential components of many ionic liquids which are used as catalysts or solvents for catalysts in chemical reactions such as eg dimerisation, oligomerisation and polymerisation of olefins. Ionic liquids are primarily salts or mixtures of salts which melt below, at or above room temperature. Such salt mixtures include (alkyl) aluminium halides in combination with one or more of imidazolium halides, the latter being preferably substituted eg by alkyl groups. Examples of the substituted derivatives of the latter include one or more of 1-methyl-3-ethylimidazolium halide, 1-methyl-3-butylimidazolium halide, 1-ethyl-3-butylimidazolium halide and the like. These ionic liquids consist of a mixture where the mole ratio of the (alkyl) aluminium halide to the imidazolium halide is usually >1.0 but may be 1.0 or <1.0. Ionic liquids may also be simple binary salts, such as 1-methyl-3-butylimidazolium hexafluorophosphate, 1-methyl-3-ethylimidazolium acetate and 1-methyl-3-butylimidazolium nitrate.
The advantage of making the imidazolium salts by the present process, ie by reaction of two neutral molecules, is that it generates ionic liquids which are not contaminated by unwanted halide ions or metal ions. In addition to providing a novel and convenient route to known ionic liquids, it also permits the generation of novel ionic liquids, such as 1-methyl-3-alkylimidazolium alkoxides, 1-methyl-3-alkylimidazolium hydrogencarbonates and the corresponding imidazolium hydroxide which were hitherto unknown.
Thus according to a second aspect of the present invention, there is provided an imidazolium carbene of formula (I) as hereinbefore defined whenever prepared by the present invention.
According to a third aspect of the present invention, there is provided preparation of imidazolium salts of formula (II)
wherein R 1 and R 2 , which can be the same or different, are hydrogen or linear or branched hydrocarbyl groups and X − is a cation,
comprising the reaction of an imidazolium carbene of formula (I) as hereinbefore defined with an acid or alcohol.
According to a fourth aspect of the present invention, there is provided an imidazolium salt of formula (II) as hereinbefore defined whenever prepared by the present invention.
According to a fifth aspect of the present invention, there is provided use of an imidazolium salt of formula (II) as hereinbefore defined as an ionic liquid.
The present invention is further illustrated with reference to FIG. 1 and the following Examples:
EXAMPLES
1. Preparation of Carbenes
1.1 1-Ethyl-3-methylimidazol-2-ylidine
All manipulations were performed under a stream of dry dinitrogen or in a glove box. In a round-bottomed flask (50 cm 3 ), 1-ethyl-3-methyl imidazolium chloride (8.7 g, 50 mmol) and a commercial sample of potassium t-butoxide (7.7 g, 75 mmol, unpurified, 95% ex Aldrich) were heated in a Kugelrohr apparatus at 125° C. at about 130 Pa (1 mm Hg) pressure for 1 h. A colourless oil was collected and transferred to a clean round-bottomed flask (50 cm 3 ). This was redistilled on the Kugelrohr apparatus to give 5.3 g of a colourless oil. NMR analysis showed this oil to be 1-ethyl-3-methylimidazol-2-ylidine (95% yield). The product has a tendency to rapidly turn orange on contact with the air. The carbene produced by this Example was characterised using 1 H and 13 C NMR spectroscopy and the following peaks were identified:
1 H NMR 7.21 1H singlet 13 C NMR 208.5 C 7.08 1H singlet 117.5 CH 4.03 2H quartet 116.2 CH 3.73 3H singlet 42.5 CH 2 1.38 3H triplet 34.7 CH 3 14.6 CH 3
1.2 1-Butyl-3-methylimidazol-2-ylidine
The same procedure as in Section 1.1 above was used for making the analogous butyl carbene except that the reaction temperature and distillation temperature were slightly (ca. 30° C.) higher.
The carbene produced by this Examples was characterised using 1 H and 13 C NMR spectroscopy and the following peaks were identified:
1 H NMR 7.16 1H singlet 13 C NMR 210.2 C 7.02 1H singlet 117.5 CH 4.02 2H quartet 116.7 CH 3.68 3H singlet 47.4 CH 2 1.78 2H pentet 34.6 CH 3 1.38 2H hextet 31.3 CH 2 0.90 3H triplet 17.1 CH 2 10.9 CH 3
2. Preparation of Imidazolium Salts:
The method depends upon the careful mixing of a stoichiometric amount of carbene with an acid or alcohol, or, alternatively, excess acid, if the excess acid is readily separable (eg carbonic acid).
2.1 1-Butyl-3-methylimidazolium hydrogencarbonate:
A mixture of 1-butyl-3-methylimidazolium chloride (4.37 g, 25 mmol) and potassium t-butoxide (3.95 g, 35 mmol) was placed in a 50 cm 3 round bottomed flask in a glove box. The flask was transferred to a Kugelrohr apparatus and the mixture was heated at 150° C., at about 130 Pa (1 mm Hg) pressure. A colourless oil (1-butyl-3-methylimidazol-2-ylidine) was collected. The reaction was adjudged to be complete after 30 minutes and the oil was immediately poured into a 500 cm 3 round bottom flask containing de-ionised water (100 cm 3 ) and dry ice (ca. 10 g). The flask was agitated until the dry ice had evaporated and the water was evaporated on a rotary evaporator. Toluene (3×50 cm 3 ) was added to the flask and removed on a rotary evaporator (this procedure was used to azeotropically remove water from the ionic liquid) and finally, the resultant viscous brown oil was heated to 50° C. at 133.4 Pa (1 mm Hg) for 2 hours. Weight of product=3.51 g, yield=70%. The same NMR spectroscopy as used previously to characterise the carbene was used to characterise the imidazolium salts. The results were as follows:
1 H NMR 8.85 1H singlet 13 C NMR 159.0 C(HCO 3 ) 7.61 1H singlet 135.7 CH 7.57 1H singlet 122.0 CH 4.99 singlet (HOD) 120.6 CH 4.31 2H triplet 47.7 CH 2 4.02 3H singlet 34.1 CH 3 1.95 2H hextet 29.7 CH 2 1.42 2H pentet 17.2 CR 2 1.03 3H triplet 11.2 CH 3 Solvent = D 2 O IR (NaCl plate): ν = 1666 cm −1 C═O ν = 3600-2350 cm −1 O—H Empirical solubilities: Soluble: water, methanol, ethanol Partially soluble: acetone Insoluble: ethyl acetate, diethyl ether
2.2 1-Ethyl-3-methylimidazolium methoxide:
A mixture of 1-ethyl-3-methyl imidazolium chloride (3.66 g, 25 mmol) and potassium t-butoxide (3.96 g, 35 mmol) was placed in a 50 cm 3 round bottomed flask in a glove box. The flask was transferred to a Kugelrohr apparatus and the mixture was heated at 140° C., at about 130 Pa (1 mm Hg) pressure. A colourless oil (1-ethyl-3-methylimidazol-2-ylidine) was collected. The reaction was adjudged to be complete after 30 minutes and the apparatus was repressurised with dry nitrogen. Anhydrous methanol (1.0 cm 3 , 27 mmol) was added to the carbene by syringe. Excess methanol was removed by reconnecting to the vacuum line (1 mm Hg) and rotating the reaction vessel for 1 hour. The NMR spectra were recorded neat, using an acetone-d 6 external lock. Yield estimated at 85-90% (based on NMR).
1 H NMR 8.99 1H singlet (broad) 13 C NMR 190.2 CH (broad) 7.56 1H singlet 118.4 CH 7.45 1H singlet 116.4 CH 4.38 2H quartet 45.1 CH 2 4.02 3H singlet 42.3 CH 3 3.66 3H singlet 34.0 CH 3 1.63 3H triplet 14.0 CH 3
Note: The product is extremely hygroscopic and decomposes slowly at room temperature. This decomposition appears to be water catalysed.
2.3 1-Butyl-3-methylimidazolium propoxide:
1-Butyl-3-methylimidazol-2-ylidine (2.00 g, 16.1 mmol) was prepared as in Section 2.1 above. This was cautiously added to n-propanol (0.97 g, 16.1 mmol) by pipette in a glove box. The NMR spectra were recorded neat, using an acetone-d 6 external lock. Yield estimated at 95% (based on NMR).
1 H NMR 8.92 1H singlet (broad) 13 C NMR 190.1 CH (broad) 7.46 1H singlet 118.2 CH 7.41 1H singlet 117.3 CH 4.33 2H triplet 59.8 CH 2 4.02 3H singlet 47.2 CH 2 3.86 2H triplet 34.0 CH 3 2.10 2H pentet 30.9 CH 3 1.86 2H hexet 29.0 CH 2 1.60 2H hexet 24.3 CH 2 1.20 3H triplet 10.8 CH 3 1.19 3H triplet 8.0 CH 3
Note: The product is extremely hygroscopic and decomposes very slowly at room temperature. This decomposition appears to be water catalysed. It appears to be significantly more stable than 1-ethyl-3-methylimidazolium methoxide.
2.4 1-Butyl-3-methylimidazolium acetate:
1-Butyl-3-methylimidazol-2-ylidine (2.00 g, 16.1 mmol) was prepared as in Section 2.1 above. This was cautiously added to glacial acetic acid (0.97 g, 16.1 mmol) by pipette in a glove box over a 15 minute period. The NMR spectra were recorded neat, using an acetone-d 6 external lock. Yield estimated at 95% (based on NMR).
1 H NMR
10.61
1H
singlet
13 C NMR
172.1
C
8.45
1H
singlet
136.3
CH
8.32
1H
singlet
121.6
CH
4.31
2H
triplet
120.5
CH
4.02
3H
singlet
46.0
CH 2
1.72
2H
pentet
32.8
CH 3
1.70
3H
singet
29.6
CH 2
1.15
2H
hexet
28.6
CH 3
0.72
3H
triplet
22.2
CH 2
10.4
CH 3
The following are farther non-limiting examples;
1-hexyl-3-methylimidazolylidine.
1-hexyl-3-methylimidazolium chloride (10.0 g) was placed in a 100 cm 3 Kugelrohr flask and connected to a Kugelrohr apparatus (FIGS. 1,2). This was heated at 100° C. for 1 hour at 1 mmHg pressure, then cooled to room temperature. The flask was transferred to a dry glove box and potassium tert-butoxide (10.0 g) was added to the 1-hexyl-3-methylimidazolium chloride. The apparatus was reassembled and heated at 160° C. for 2 hours. During this period, 1-hexyl-3-methylimidazolylidine distilled into the receiving flask and the tert-butanol condensed into a liquid nitrogen trap connected to the vacuum pump. The orange coloured 1-hexyl-3-methylimidazolylidine was analysed by 1 H and 13 C NMR spectroscopy. The crude product was redistilled in the Kugelrohr apparatus (bp=160° C. at 1 mmHg) to give an extremely moisture sensitive colorless oil (6.5 g, 79%); δH (300 MHz, neat, external TMS reference) 6.97 (1H, s), 6.92 (1H, s), 3.94 (2H, q, J=7.3 Hz), 3.62 (3H, s), 1.72 (2H, m), 1.26 (6H, m), 0.85 (3H, t, J=7.3 Hz); 13 C NMR δC (75 MHz, neat, external TMS reference) 209.6 (C), 119.6 (CH), 118.5 (CH), 49.9 (CH 2 ), 35.7 (CH 3 ), 31.5 (CH 2 ), 31.3 (CH 2 ), 31.1 (CH 2 ), 22.1 (CH 2 ), 13.4 (CH 3 ).
1-Hexyl-3-methylimidazolium Hydrogen Carbonate
Solid carbon dioxide (dry ice) (ca. 25 g) was added to distilled water (100 g), with stirring from a magnetic stirring flea in a 500 cm 3 beaker, in a fume hood. 1-hexyl-3-methylimidazolylidine (6.0 g, 36.1 mmol) was added to the water and carbon dioxide mixture. The mixture was allowed to warm to room temperature, and was washed with dichloromethane (3×25 cm 3 ). The water was evaporated on a rotary evaporator (making sure the temperature did not exceed 60° C.) and the 1-hexyl-3-methylimidazolium hydrogen carbonate was dried under vacuum (1 mmHg) for 4 hours at 60° C. This gave 7.8 g (94%) of a straw coloured viscous liquid. δH (300 MHz, D 2 O, TMS reference) 8.28 (1H, s, D 2 O exchangable) 7.43 (1H, s), 7.33 (1H, s), 4.78 (1H, s), 4.04 (2H, q, J=7.3 Hz), 3.77 (3H, s), 1.73 (2H, m), 1.32 (6H, m), 0.71 (3H, t, J=7.3 Hz); 13 C NMR δC (75 MHz, D 2 O, TMS reference) 161.3 (C), 135.8 (CH, D 2 O exchangeable), 123.8 (CH), 122.5 (CH), 49.8 (CH 2 ), 35.9 (CH 3 ), 30.6 (CH 2 ), 29.5 (CH 2 ), 25.3 (CH 2 ), 22.1 (CH 2 ), 13.6 (CH 3 ).
This salt could be converted to other 1-hexyl-3-methylimidazolium salts (or ionic liquids) by reaction with the acid form of the desired anion in water, followed by evaporation of the water.
1-Octyl-3-methylimidazolylidine.
1-Octyl-3-methylimidazolium chloride (5.0 g, 21.7 mmol) was placed in a 50 cm 3 Kugelrohr flask and connected to a Kugelrohr apparatus (FIG. 1). This was heated at 100° C. for 1 hour at 1 mmHg pressure, then cooled to room temperature. The flask was transferred to a dry glove box and potassium tert-butoxide (5.0 g, excess) was added to the 1-octyl-3-methylimidazolium chloride. The apparatus was reassembled and heated at 200° C. for 1 hour. During this period, 1-octyl-3-methylimidazolylidine distilled into the receiving flask and the tert-butanol condensed into a liquid nitrogen trap connected to the vacuum pump. The crude product was redistilled in the Kugelrohr apparatus (bp=190-200° C. at 1 mmHg) to give an extremely moisture sensitive oil (2.87 g, 68%). The yellow coloured 1-octyl-3-methylimidazolylidine solidified on standing was immediately used in further reactions.
1-Octyl-3-methylimidazolium acetate
1-Octyl-3-methylimidazol-2-ylidine (2.00 g, 16.1 mmol) prepared above, was cautiously added to glacial acetic acid (0.97 g, 16.1 mmol) by pipette in a glove box over a 15 minute period with stirring from a magnetic stirrer flea. The ionic liquid formed was used unpurified. NMR data: δH (300 MHz, neat, external TMS reference) 10.61 (1H, s), 8.45 (1H, s), 8.32 (1H, s), 4.31 (3H, t), 4.02, (3H, s), 1.72 (2H, m), 1.70 (2H, s), 1.15 (10H, m), 0.72 (3H, t, J=7.2 Hz); 13 C NMR δC (75 MHz, neat, external TMS reference) 172.1 (C), 136.3 (CH), 121.6 (CH), 120.5 (CH), 46.0 (CH 2 ), 32.8 (CH 3 ), 29.6 (5×CH 2 ), 28.6 (CH 3 ), 22.2 (CH 2 ), 10.4 (CH 2 ). | The disclosure herein relates to imidazole carbenes and imidazole carbene salts. The disclosure also relates to the synthesis of imidazole carbenes and imidazole carbene salts. The imidazole carbenes disclosed include those synthesized by reacting an imidazole halide with a base under reduced pressure. The imidazole carbene salts disclosed include those synthesized by reaction of imidazole carbenes with an acid or alcohol suitable for creation of a salt. The disclosure also relates to the use of imidazole carbenes and imidazole carbene salts for the synthesis of organic liquids. | 2 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to an ultrafine nickel powder which may be used for an internal electrode of a laminated ceramic capacitor, an electrode of a secondary cell, a fuel cell or the like.
[0003] 2. Description of the Related Art
[0004] Much attention has been paid to an ultrafine nickel powder as material to make up electrodes of various parts of electronic devices. Such electrodes include an internal electrode of a laminated ceramic capacitor, a porous electrode of a hydrogen nickel secondary cell, and a hollow porous electrode of a fuel cell for taking out electric energy by electrochemically carrying out oxidization reaction of fuel.
[0005] The following will describe the ultrafine nickel powder, mainly giving an internal electrode of the laminated ceramic capacitor as an example.
[0006] The laminated ceramic capacitor is a member obtained by laminating dielectric ceramics, such as titanium oxide, barium titanate or complex perovskite, and metal inner electrodes alternately in layers, compressing and sintering it to be united. Recently, the market for the laminated ceramic capacitor for parts of electronic devices has grown rapidly. With the advance of the performance of electrical devices, the laminated ceramic capacitor has been promoted to be downsized and have larger capacitance. Therefore, the inner electrode has been made thinner. In the prior art, palladium was used for the inner electrode of the laminated ceramic capacitor. Recently, however, use of nickel has been increasing because of low price and high reliability.
[0007] Japanese Patent Application Laid-Open No.Hei. 1-136910 discloses an invention for producing a nickel powder having a purity of 99% or more and a particle size of 0.1 to 0.3 μm in a wet process. However, this publication dose not include the description that paste is actually produced from the particles and the paste is used for an electrode of electrical parts. The inventors have investigated the nickel powder, and then found out that the inner electrode made by using the paste of the nickel powder produced in the wet process as in this prior art and laminating it in layers is large in volume change when sintered, so as to easily cause delamination and/or cracks. In the wet process, the crystals in the particles of the ultrafine nickel powder do not grow up to large sizes, and become a cluster of primary particles because the temperature at which the ultrafine nickel powder is produced is relatively low, for example, lower than 100° C. Thus, the internal electrode is easily sintered excessively or is large in volume change when sintered.
[0008] Japanese Patent Application Laid-Open No.Sho. 64-80007 discloses paste for electrodes of a porcelain condenser using a nickel powder having an average particle size of 1.0 μm and a purity of 99.9%. In order to prevent generation of cracks and/or delamination when this electrode paste is sintered, addition of carbide particles into this paste is described. However, this publication never describes any influence of the characteristics of the nickel particles themselves on generation of the cracks and/or delamination.
[0009] In the production of any laminated ceramic capacitor, it is important techniques to prevent generation of cracks and/or delamination when sintered, as well as to make thinner layers, miniaturize the size and achieve high capacitance of the inner electrode. Thus, an ultrafine nickel powder has been desired which make it possible to restrain generation of cracks and/or delamination and produce a material for an electrode having a low resistivity.
SUMMARY OF THE INVENTION
[0010] In the light of the aforementioned problems in the prior art, an object of the present invention is to provide an improved ultrafine nickel powder. Namely, the object of the invention is to provide an ultrafine nickel powder having the following properties.
[0011] (a) Cracks and/or delamination are not liable to be caused in the process for producing a laminated ceramic capacitor.
[0012] (b) An internal electrode can be made into a thin layer.
[0013] (c) A low electrical resistivity can be realized as an electrode material.
[0014] The present invention provides an ultrafine nickel powder comprising a sulfhur content of 0.02 to 1.0% by weight and an average particle size of 0.1 to 1.0 μm. The ultrafine nickel powder is preferably ones produced from vapor phase hydrogen-reducing vapor of nickel chloride. The ultrafine nickel powder can be used for a porous electrode of a nickel hydrogen cell, or a hollow porous electrode of a fuel cell, but are especially suitable for use as a laminated ceramic capacitor electrode having properties for restraining cracks and/or delamination and for making the electrode thinner and the electric resistivity lower.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] [0015]FIG. 1 is a microscopic photography of an ultrafine nickel powder for a laminated ceramic capacitor in Example 1. Magnification: 40000×.
[0016] [0016]FIG. 2 is a microscopic photography of an ultrafine nickel powder for a laminated ceramic capacitor in Example 2. Magnification: 40000×.
[0017] [0017]FIG. 3 is a microscopic photography of an ultrafine nickel powder for a laminated ceramic capacitor in Comparative Example 1. Magnification: 40000×.
[0018] [0018]FIG. 4 is a microscopic photography of an ultrafine nickel powder for a laminated ceramic capacitor in Comparative Example 2. Magnification: 40000×.
[0019] [0019]FIG. 5 is a microscopic photography of an ultrafine nickel powder for a laminated ceramic capacitor in Example 3. Magnification: 10000×.
[0020] [0020]FIG. 6 is a microscopic photography of an ultrafine nickel powder for a laminated ceramic capacitor in Example 4. Magnification: 10000×.
[0021] [0021]FIG. 7 is a microscopic photography of an ultrafine nickel powder for a laminated ceramic capacitor in Comparative Example 3. Magnification: 10000×.
[0022] [0022]FIG. 8 is a microscopic photography of an ultrafine nickel powder for a laminated ceramic capacitor in Comparative Example 4. Magnification: 10000×.
[0023] [0023]FIG. 9 is a microscopic photography of an ultrafine nickel powder for a laminated ceramic capacitor in Example 5. Magnification: 400×.
[0024] [0024]FIG. 10 is a microscopic photography of an ultrafine nickel powder for a laminated ceramic capacitor in Example 6. Magnification: 400×.
[0025] [0025]FIG. 11 is a microscopic photography of an ultrafine nickel powder for a laminated ceramic capacitor in Comparative Example 5. Magnification: 400×.
[0026] [0026]FIG. 12 is a microscopic photography of an ultrafine nickel powder for a laminated ceramic capacitor in Comparative Example 6. Magnification: 4000×.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0027] The ultrafine nickel powder is made into paste, and the paste is printed on a dielectric layer film to form an internal electrode. In order to make the internal electrode thin and dense, the average particle size of the ultrafine nickel powder is suitably from 0.1 to 1.0 μm.
[0028] If the average particle size is less than 0.1 μm, the nickel layer shrunk excessively when the laminated ceramic capacitor is sintered, so that the internal electrode will become porous. The ultrafine nickel powder having an average particle size of less than 0.1 μm is not preferable because the internal electrode will have high resistivity, or delamination and/or cracks will be caused. On the contrary, if the average particle size is more than 1.0 μm, it will be difficult to make the internal electrode of the laminated ceramic capacitor into a thin layer. The ultrafine nickel powder having an average particle size of more than 1.0 μm is not preferable because the surface of the internal electrode layer will have large irregularities, resulting in generation of cracks. The more preferable average particle size is from 0.2 to 0.6 μm. The average particle size is defined by the 50% particle size (d 50 ) in particle size distribution on the basis of the number of particles, obtained from image-analyzing an electron microscopic photograph of the particles.
[0029] For an ultrafine nickel powder-for a laminated ceramic capacitor, it is important that the particle shape is spherical, and the size is proper. In the process for producing a laminated ceramic capacitor, spherical particles exhibit ideal characteristics that make it possible to form a thin layer internal electrode having a high density of an ultrafine nickel powder and permit no cracks nor delamination to be generated. The inventors have found that the sulfur content therein has a decisive effect in order to make a shperical ultrafine nickel powder. Unless the sulfur content is within the range of 0.02% to 1.0 wt %, angular particles such as hexahedral or octahedral particles appear. These partcicles are not desirable to make a laminated ceramic capacitor. When the sulfur content is from 0.02 to 1.0% by weight, ultrafine nickel powder particles are sufficiently spherical. Therefore, the sulfur content should be controlled within this range to produce spherical ultrafine nickel powder particles.
[0030] The ultrafine nickel powder having the aforementioned average particle size and sulfur content is preferable because it may be easily produced by controlling the sulfur content with a vapor phase hydrogen-reduction process. The vapor phase hydrogen-reduction process for nickel-chloride can be carried out in a reactor wherein arranged are in sequence a vaporizing section, a reacting section and a cooling section. In the vaporizing section, NiCl 2 is vaporized in a crucible. In the reacting section, NiCl 2 vapor carried with innert gas contacts with supplied hydrogen at a controlled temperature. And, in the cooling section, the mixture of synthesized Ni particles and by-product gas is cooled.
[0031] The spherical ultrafine nickel power particles can be obtained by the process that either one or both of sulfur and sulfide are accompanied by nickel chloride vapor, inert gas or hydrogen.
[0032] The ultrafine nickel powder produced by such a process are made spherical and further the particle sizes of the ultrafine nickel powder are made substantially uniform so that the particle-size distribution will become sharp. Furthermore, good effect can be obtained that the individual ultrafine nickel powder is not composed of a condensed or sintered body of a lot of finer primary particles but is composed of a single particle.
[0033] An ultrafine nickel powder to produce high quality laminated ceramic capacitors has been desired. The inventors have carried out experiments on production of laminated ceramic capacitors using various kinds of nickel powders. The characteristics of such powder should be of low resistivity as an electrode material, hard to generate cracks and/or delamination and easy to make a thinner internal electrode. It has been found that such characteristics depends upon the size and shapes of the ultrafine nickel powder particles.
[0034] The preferable average particle size is limited to the range from 0.1 to 1.0 μm. If the ultrafine nickel powder whose average particle size is less than 0.1 μm is used, the nickel layer is shrunk because of extremely fine by particles when the laminated ceramic capacitor is sintered, so that the internal electrode will become porous. The electric resistivity of the capacitor will also become high, or delamination and /or cracks will be generated. Thus, the ultrafine nickel powder having an average particle size of less than 0.1 μm are not preferred. On the other hand, if the average particle size is more than 1.0 μm, it will be difficult to make the internal electrode of the laminated ceramic capacitor into a thin layer. The surface of the internal electrode layer will come to have large irregularities, resulting in frequent generation of cracks.
[0035] As the shape of the particles becomes more spherical, better results are obtained. According to the research for the present invention, it has been made obvious that making the ultrafine nickel powder spherical can be controlled by the sulfur content in the ultrafine nickel powder. This is because the sulfur functions so that the crystal growth on the surface of the ultrafine nickel powder particle will develop symmetrically in all directions.
[0036] As described above, the sulfur content in ultrafine nickel powder having an average particle size of 0.1-1.0 μm is set into the range from 0.02 to 1.0% by weight so that the ultrafine nickel powder can be made spherical. The following will describe specific examples, referring to electron microscopic photographs.
EXAMPLES A
[0037] The sulfur contents in the ultrafine nickel powder having an average particle size of about 0.1 μm were varied, and then they were observed with a microscope.
Example 1
[0038] When the sulfur content in the ultrafine nickel powder having an average of 0.11 μm was 0.021% by weight, particles of the ultrafine nickel powder were sufficiently spherical as shown in FIG. 1.
Example 2
[0039] When the sulfur content in the ultrafine nickel powder having an average of 0.10 μm was 1.0% by weight, particles of the ultrafine nickel powder were sufficiently spherical as shown in FIG. 2.
Comparative Example 1
[0040] When the sulfur content in the ultrafine nickel powder having an average of 0.12 μm was 0.012% by weight, the percentage of particles having angular shapes (hexahedral or octahedral particles) to the total particles increased as shown in FIG. 3.
Comparative Example 2
[0041] When the sulfur content in the ultrafine nickel powder having an average of 0.11 μm was 1.4% by weight, the percentage of particles having angular shapes (hexahedral or octahedral particles) to the total particles increased as shown in FIG. 4.
EXAMPLES B
[0042] The sulfur contents in the ultrafine nickel powder having an average particle size of about 0.4 μm were varied, and then they were observed with a microscope.
Example 3
[0043] When the sulfur content in the ultrafine nickel powder having an average of 0.40 μm was 0.020% by weight, particles of the ultrafine nickel powder were sufficiently spherical as shown in FIG. 5.
Example 4
[0044] When the sulfur content in the ultrafine nickel powder having an average of 0.42 μm was 0.99% by weight, particles of the ultrafine nickel powder were sufficiently spherical as shown in FIG. 6.
Comparative Example 3
[0045] When the sulfur content in the ultrafine nickel powder having an average of 0.44 μm was 0.011% by weight, the percentage of particles having angular shapes (hexahedral or octahedral particles) to the total particles increased as shown in FIG. 7.
Comparative Example 4
[0046] When the sulfur content in the ultrafine nickel powder having an average of 0.41 μm was 1.5% by weight, the percentage of particles having angular shapes (hexahedral or octahedral particles) to the total particles increased as shown in FIG. 8.
EXAMPLES C
[0047] The sulfur contents in the ultrafine nickel powder having an average particle size of about 1.0 μm were varied, and then they were observed with a microscope.
Example 5
[0048] When the sulfur content in the ultrafine nickel powder having an average of 1.0 μm was 0.019% by weight, particles of the ultrafine nickel powder were sufficiently spherical as shown in FIG. 9.
Example 6
[0049] When the sulfur content in the ultrafine nickel powder having an average of 0.99 μm was 1.0% by weight, particle of the ultrafine nickel powder were sufficiently spherical as shown in FIG. 10.
Comparative Example 5
[0050] When the sulfur content in the ultrafine nickel powder having an average of 0.98 μm was 0.010% by weight, the percentage of particles having angular shapes (hexahedral or octahedral particles) to the total particles increased as shown in FIG. 11.
Comparative Example 6
[0051] When the sulfur content in the ultrafine nickel powder having an average of 1.1 μm was 1.3% by weight, the percentage of particles having angular shapes (hexahedral or octahedral particles) to the total particles increased as shown in FIG. 12.
[0052] The above-mentioned results are together shown in Table 1.
TABLE 1 Average Sulfur Spherical particle content characteristic Rate of size (% by of an ultrafine cracks and (μm) weight) nickel powder delamination Example 1 0.11 0.021 good ⊚ Example 2 0.10 1.0 good ⊚ Comparative 0.12 0.012 Many angular X Example 1 particles Comparative 0.11 1.4 Many angular X Example 2 particles Example 3 0.40 0.020 good ⊚ Example 4 0.42 0.99 good ⊚ Comparative 0.44 0.011 Many angular X Example 3 particles Comparative 0.41 1.5 Many angular X Example 4 particles Example 5 1.0 0.019 good ∘ Example 6 0.99 1.0 good ∘ Comparative 0.98 0.010 Many angular X X Example 5 particles Comparative 1.1 1.3 Many angular X X Example 6 particles
[0053] As understood from the above, in the cases wherein the sulfur content in the ultrafine nickel powder was from 0.02 to 1.0% by weight, the ultrafine nickel powder became sufficient spherical. It is considered that particles of the ultrafine nickel powder are made spherical because the surface growth of the nickel particle progresses almost uniformly in all directions. Particles of the ultrafine nickel powder can be made spherical by controlling the sulfur content within a proper range.
[0054] Pastes of the respective particles obtained from Examples 1-6 and Comparative Examples 1-6 were used to produce laminated ceramic capacitors, and whether or not delamination was caused when the capacitors were sintered was examined. The respective pastes of the ultrafine nickel powder were printed-on green sheets wherein the thickness of their dielectrics was about 3 μm, so that the thickness of the pastes would be 2 μm. Electrodes and dielectric layers were alternately laminated so that the total number of the layers would 200, and then the multilayer body was compressed, cut, and dried. After binders were removed off, the multilayer body was sintered at 1200° C. in mixed gas of hydrogen and nitrogen. A laminated capacitor 3.2 mm long, 1.6 mm wide and 1.6 mm thick was obtained.
[0055] For 300 laminated capacitors thus obtained, whether cracks and/or delamination were generated or not was examined, and results from the examination are also shown in Table 1. In Table 1, the rate of generation of cracks or delamination is shown as follows:
[0056] ⊚ : 1% or less,
[0057] ◯ : more than 1% but 10% or less,
[0058] X : more than 10% but 50% or less, and
[0059] XX : more than 50%.
[0060] As shown in the columns for the Examples, when the ultrafine nickel powder meeting the characteristics defined in the present invention were used, the rate of generation of cracks and/or delamination was low, and the internal electrode was be able to be made into a thin layer. On the contrary, in the Comparative Examples, many cracks and delamination were generated because the samples therein did not meet the characteristics defined in the present invention.
[0061] In the above description, the ultrafine nickel powder was explained mainly about ones used for internal electrodes of laminated ceramic capacitors. However, the ultrafine nickel powder according to the present invention is not limited to this application, and can be applied to an electrode material for a secondary cell, fuel cell and others.
[0062] The present invention makes it possible to provide an ultrafine nickel powder which has atisfactory particle shapes and is suitable for various applications, and in particular to make internal electrodes of a laminated ceramic capacitor into thin layers, reduce their electrical resistance, and prevent generation of delamination and/or cracks when the capacitor is sintered. | Provided is an ultrafine nickel powder suitable for a laminated ceramic capacitor electrode material. According to the ultrafine nickel powder, cracks and/or delamination are not liable to generate in the process for producing a ceramic capacitor, and its internal electrode can be made into a thinner layer, and the electric risistivity of the capacitor can be made low. The ultrafine nickel powder has an average particle size of 0.1-1.0 μμm, having the sulfur content of 0.02-1.0 % by weight, and particles thereof being spherical, thereby exhibiting excellent properties. They can be produced by vapor phase hydrogen-reducing process using nickel chloride vapor. | 8 |
This invention relates to manually actuated hydraulic valves of the type used, for example, as a booster valve for a hydraulic brake and more particularly, to a pulsation limiter incorporated in such a valve which reduces or eliminates the transient effects on the valve system as a whole caused by partial retraction, especially a sudden retraction, of the external actuator.
In U.S. Pat. No. 4,287,813, there is described a two stage concentric hydraulic brake booster system which includes a brake pedal, a return spring therefor, and a link connecting the pedal to an input sleeve in the booster valve housing. Telescoped within the input sleeve is a metering spool which upon external actuation of the input sleeve delivers hydraulic pressure to an expansible chamber having a moveable power piston which in turn engages a conventional dual master brake cylinder. Although for the most part, this brake booster has worked quite well, it was discovered that undamped and annoying pulsation of the pedal-input sleeve-metering spool-spring system can occur when the brake pedal is rapidly but not completely retracted. Substantial pulsating pressure transients occur in the booster valve and appear to result from both the operator and the hydraulic components simultaneously reacting to rapid changes in braking pressure caused by a partial retraction of the brake pedal and input sleeve thus overcompensating for undershoots in the pressure.
SUMMARY OF THE INVENTION
Accordingly, it is a primary object of the invention described and claimed herein to provide a manually actuated hydraulic valve system with a means of reducing or eliminating such externally induced pressure pulsations.
A more specific object of the invention is to provide a hydraulic brake booster valve system with a means of eliminating or reducing pressure transients in said valve which may occur as a result of partial release of the applied braking pressure.
A still more specific object of the invention is to provide a motion retarder in said booster valve assembly which only permits a relatively slow return of the input sleeve when the brake pedal is retracted.
The above and other objects of the invention as may become apparent herein are specifically met in a braking system having a valve housing, an input sleeve in the housing connected to an operator actuated, spring returned brake pedal, and a metering spool within the input sleeve wherein actuation of the input sleeve causes vehicle supplied hydraulic pressure to actuate a power piston disposed to engage a master brake cylinder. A spring biased, motion retarding plunger in an auxiliary bore within the valve housing and having a helical groove disposed on its periphery abuts against the input sleeve during the initial portion of its travel to actuate the brakes, a check valve in the plunger allowing filling of the expanding cavity in the auxiliary bore behind the motion retarding plunger. When the brake pedal is released partially or completely, the input sleeve moves until it abuts against the plunger. Thereafter, the pressure buildup in the auxiliary bore cavity closes the check valve in the plunger and the input sleeve can only move relatively slowly back to its initial position as the fluid trapped in the auxiliary bore cavity exits through the helical groove. In addition to the advantages recited above, the helical groove on the plunger allows very small quantities of fluid to be used yet provides adequate increases in the return time of the input sleeve by increasing the resisted path of travel of the fluid. The net effect is to increase the return time of the input sleeve by a factor of 10 allowing sufficient time for the valve components to gradually react to changes in their position.
DESCRIPTION OF THE DRAWINGS
Other objects and advantages of the invention will become more apparent upon reading the following detailed description of the invention and upon reference to the drawings, in which:
FIG. 1 is a partly schematic, partly broken away, side elevation of a braking system incorporating the present invention;
FIG. 2 is a enlarged sectional view of the booster valve assembly of the braking system of FIG. 1 taken along the line 2--2 thereof; and
FIG. 3 is a still larger view of only the auxiliary bore and plunger assembly incorporated within the brake system of FIGS. 1 and 2.
DETAILED DESCRIPTION OF THE INVENTION
Turning now to FIG. 1 of the drawings, a hydraulic booster brake system 10 is shown including a conventional dual braking cylinder 12 connected separately to the front wheel brake cylinders 14 and to the rear wheel brake cylinders 16 of a vehicle partially shown at 18 such as a wheel loader. The dual cylinder 12 responds directly to an operator input pedal 20 through the intermediary of a two stage concentric brake booster 22 for supplying the wheel cylinders 14 and 16 with hydraulic brake fluid under pressure to establish brake drag as desired on the vehicle wheels (not shown) or to cause them to stop.
In more specific detail, in the foot brake mechanism, establishing the master brake setting and master boost pressure setting, the pedal 20 forms one of the arms of a bellcrank 24 secured on a fixed pivot of the operator's platform of the vehicle 18. A depending bell crank arm 26 is controlled at its outer end by an anchored brake return spring 28 and controls a rearwardly extending push link 30. The dual braking cylinder 12 carries the usual capped fluid reservoir 32 on top and is activated at its inner end by a plunger or a thrust probe 34. The probe 34 projects into the cylinder 12 to thrust against standard tandem connected, hydraulic master cylinder pistons (not shown) the leading one of which supplies one separate hydraulic line 36 for the rear wheel cylinders 16 and the trailing one of which supplies another separate hydraulic brake line 38 supplying the cylinders 14 on the vehicle front wheels (not shown). All fluid in the circuit from the reservoir 32 to the wheel cylinders is in a self-contained independent hydraulic brake system.
The push link 30 operates the booster valve 22 ordinarily under motion amplification and hydraulic force amplification so as to cause the braking operation through the power piston connected probe 34. More particularly, a clevis 40 to which the link 30 is pivotally connected is threaded solidly into and is carried by an input signal spool or sleeve 42 disposed in the booster valve bore 122 and mechanically moves the input sleeve into various positions within the booster valve 22. The booster valve is supplied with hydraulic fluid from a pressurized circuit separate from the independent system of the brake cylinder 12.
Referring now to FIG. 2, at its innermost end, the input sleeve 42 is provided with a flanged spool stop 82 threaded into the end of the input sleeve 42 to abut against the end of that portion of the booster valve 22 containing the main bore 122. The spool stop flange operates in the power piston cylinder 86 in the bore 118 and is provided with a hollow center portion 84 to permit the passage of fluid longitudinally therethrough. Intermediate its ends and within the booster cylinder bore 122, the input sleeve 42 is provided with a plurality of radially extending ports for communicating with the interior portion thereof including an input pressure port 75 between an interior annulus 76 and an input pressure annulus 74 in the booster valve 22 which is continuously exposed to a source of high pressure hydraulic fluid as through inlet 72. The input sleeve 42 is further provided with radial ports 66 which communicate with a drain annulus 70 in the valve housing 22 which is appropriately connected to a drain Dr such as a vehicle reservoir. A pressure sensing annulus 60 is disposed on the input sleeve 42 between the input pressure port 75 and the drain port 66 and communicates through ports 62 to the interior portion thereof. Further disposed on the exterior of the input sleeve 42 between the input port 75 and the sensing annulus 60 and also between the sensing annulus 60 and the drain port 66 are helical grooves as at 126, 128 (shown in broken lines) together forming a hydraulic potentiometer wherein the pressure in the sensing annulus 60 is dependent upon the relative exposures of the helical grooved portions 126 and 128 to their respective annuluses 70 and 74.
Concentrically disposed within the input sleeve 42 is a metering spool 44 having one end in sensing chamber 52 stopped by the internal end 54 of the clevis 40 threaded into the outer end of the input sleeve 42. The other end of the metering spool 44 is stopped by the threaded end of the flanged stop 82. A weak spring 56 in the sensing chamber 52 biases the spool 42 toward the stop 82. The metering spool 44 is further provided at its inner end with an internal chamber 80 which communicates through a radial port and annulus with the internal input annulus 76 of the input sleeve 42, the pressure being throttled down from the input pressure in 74 by the action of the outer diameter of the metering spool 44 with the left edge of the internal annulus groove 76 in the input sleeve. The pressure in the internal chamber 80 of the metering spool 44 is communicated directly through the passage 84 to the variable volume power piston cylinder chamber 86 which contains the power piston 98 to which the thrust probe 34, which actuates the master cylinder a is securely bolted. An internal axially extending passage 92 extends from the chamber 80 within the metering spool 44 to a radial port 90 therein positioned such that when the land 78 of the metering spool closes off the internal annulus 76 in input sleeve 42, the radial port 90 establishes communication of the internal chamber 80 with the drain annulus 70 through the radial port 66 in the input sleeve 42. The metering spool 44 further has an axially extending passage 58 which extends from a radial port 64 which generally aligns with the sensing port 62 in the input sleeve 42 to communicate the pressure in the sensing annulus 60 to the sensing chamber 52 in the left or outer end of the input sleeve 42.
It will be appreciated that all of the above structure is recited in considerably greater detail with considerably greater functional explanation in U.S. Pat. No. 4,287,813, which patent is specifically incorporated by reference herein. However, for the purpose of the present invention the above would appear to be sufficiently explanatory of the structure, especially when considered with the following functional explanation of the booster valve 22.
When the brake pedal 20 is in the rest position, retained therein by the return spring 28, the input sleeve 42 is in its fully withdrawn position as shown in the drawings. In this position, the sensing annulus 60 is in hydraulic communication with the drain annulus 70 and thus the fluid pressure in the signal pressure chamber 52 within the input sleeve 42 is zero. Accordingly, the only force acting on the metering spool 44 is that produced by the weak spring 56 which causes the metering spool to just crack open the input annulus 76 and the input sleeve to produce about 5 psi pressure in the internal chamber 80 and power piston chamber 86. This pressure is insufficient to overcome the return spring on the power piston as well as those in the master cylinders but maintains the metering spool in a position for ready response upon actuation of the brake pedal.
When the brake pedal is depressed, the input sleeve 42 moves inwardly increasing the amount of the helical groove 126 thereon which is covered by the bore 122 of the valve while decreasing the coverage thereby of the helical groove 128. This increases the pressure in the sensing annulus 60, which pressure is communicated through the radial port 62 and 64 and through the axial passage 58 in the spool 44 to the sensing chamber 52. This signal pushes the metering spool towards the right opening up the input annulus 76 and increasing the pressure in the internal chamber 80 and also in the power piston chamber 86 causing the power piston 98 to move towards the right. It is noted that, except for transient variations, the pressure in the chamber 80 is always substantially equal to the pressure in the sensing chamber 52 and sensing annulus 60 which in turn is directly proportional to the axial position of the input sleeve helical grooves 126,128 relative to the bore of the valve housing 22. The pressure in the power piston chamber 86 acts against the flanged stop 82 and the input sleeve 42 and is thereby transmitted back to the operator through the pedal 20 and linkage so that the operator will feel the increasing braking pressure.
If the brake pedal is completely released, the sensing annulus 60 becomes connected with the drain annulus 70 and the pressure in the sensing chamber goes to zero. At the same time, the internal chamber 80 and power piston chamber 86 also become connected to the drain annulus 70 through the axial passage 92 and port 90. However, when the brake pedal is only partly retracted, for example, to reduce the pressure in the power piston chamber 86 from 300 psi to 100 psi, and especially if this is done rapidly, the pressure in the power piston chamber 86 may undershoot momentarily, for example, to 50 psi, as the metering spool reacts to the change in the position of the input sleeve. Although the metering spool will react very quickly to this undershoot and correct it, the operator's foot, which feels the pressure in chamber 86 through the flanged stop 82 and input sleeve 42, also tries, perhaps unconsciously, to correct for the undershoot by moving the input sleeve in a little bit. This overcorrecting of the undershoot causes an excitation impulse of the metering spool, and starts pressure pulsations, probably at a frequency dictated by the various springs. An operator with an educated foot could make this pulsation last 15 to 20 seconds, although it would normally last only a few seconds. In any case, the pulsations are felt by the operator through his foot and are thus undesirable.
In accordance with the present invention, means are provided to cope with this. An auxiliary bore 200 is provided in the housing 22 and intersects the power piston bore 118 just beneath the flanged edge of the spool stop 82. Disposed in the auxiliary bore 200 is a motion retarding plunger 202 slidingly fit therein in relatively close tolerance. The plunger 202 includes a rounded nose portion 204 which contacts, at least during braking, an abutting surface 206 on the axially outward face of the flanged stop 82. During braking, the power piston 98 is immediately moved away from its position shown in the drawing so that true abutment of the plunger 202 with the flanged spool stop 82 occurs. The auxiliary bore 200 is further provided with a stop shoulder 208 at its inner end to limit the travel of the plunger 200. The plunger 202 further encloses a cavity 210 in the bore 200 which is enclosed on its outer end by a plug and spring retainer 212 threaded thereinto. An O-ring 214 seals the bore 200 at the plug and leakage past the seal may be drained into the drain annulus 70. A spring 216 is disposed between the plug 212 and the plunger 202 in order to cause the plunger to follow the movement of the flanged spool stop 82 until the plunger hits the stop 208 in the bore 200.
Looking with greater detail at the plunger 202 and referring to FIG. 3, it will be seen that the plunger includes an internal passage 220 extending axially from the end of the plunger adjacent the cavity 210 and communicating therewith, to the nose end 204 of the plunger whereat it intersects radial ports 222 which communicate with the auxiliary bore 200 and the power piston chamber 86. Intermediate the ends of the axial passage 220, a check valve 224, biased by a spring 226, permits flow toward the cavity end 210 of the plunger upon overcoming the spring 226 and prohibits flow from the cavity end to the nose end. The plunger 202 is further provided with a helical groove 228 disposed on its outer cylindrical portion which extends from a first end communicating with the cavity 210 to a second end communicating with the portion of the bore 200 which is in direct communication with the power piston chamber 86. Typically, the depth of the groove 228 would be 0.5 mm.
In operation, when the input sleeve 42 moves into the valve housing 22 and the flanged spool stop 82 moves therewith, the spring 216 in the auxiliary bore 200 will push the plunger 202 to maintain contact with the abutment surface 206 of the input sleeve stop 82, the power piston 98 having moved away therefrom. As the input spool stop 82 moves further into the chamber 86, the plunger 202 will continue to follow it until it reaches its stop 208 in the auxiliary bore 200. During this movement of the plunger, hydraulic fluid in the power piston expansible chamber 86 and that portion of the auxiliary bore 200 communicating therewith enters the axial bore 220 of the plunger through the radial ports 222 and flows past the check valve 224, overcoming the spring 226, and fills the expanding cavity 210. If the input sleeve 42 moves the flanged spool stop 82 beyond the limit of the travel of the plunger caused by the stop 208, no further filling of the cavity 210 will occur.
Upon retraction of the brake pedal 20 and input sleeve 42 by the operator, the input spool stop 82 will move rapidly towards sleeve 42 until the abutting surface 206 thereon contacts the nose 204 of the plunger 202 which picks up the return load and causes an increase in the pressure in cavity 210. At this point, the check valve 224 will close and, consequently, the fluid in the cavity 210 can only escape therefrom by passing through the helical groove 228 until it reaches the portion of the auxiliary bore 200 communicating with the chamber 86. Because the helical groove is relatively small, the plunger will increase the time for retraction of the input sleeve 42 from the valve housing 22 by a factor of 10 compared to the time without the plunger assembly. While the time for retraction is still relatively short, on the order of 0.2 seconds with the plunger 202, it provides sufficient time for the metering spool 44 to maintain equilibrium between the sensing chamber and power chamber without significant undershooting. Consequently, the operator does not feel any undershoot and there is no overreaction to start the pulsation mode.
It will be appreciated that although discussed in the context of a brake booster valve assembly the motion retarding plunger may be useable in similar applications wherein manually actuated valve spools are abruptly retracted. Additionally, although the plunger has been described in connection with a preferred embodiment thereof other means of filling the cavity behind the plunger or of causing it to follow the flanged stop 82 may be possible such as maintaining an interruptable pressure supply to the cavity 210 as from the input annulus 74. | A pulsation limiter for a manually actuated hydraulic valve includes a spring biased, motion retarding plunger in an auxiliary bore within the valve housing and having a helical groove disposed on its periphery abuts against the input sleeve during the initial portion of its travel to actuate the brakes, a check valve in the plunger allowing filling of the expanding cavity in the auxiliary bore behind the motion retarding plunger. When the brake pedal is released partially or completely, the input sleeve moves until it abuts against the plunger. Thereafter, the pressure buildup in the auxiliary bore cavity closes the check valve in the plunger and the input sleeve can only move relatively slowly back to its initial position as the fluid trapped in the auxiliary bore cavity exits through the helical groove. | 1 |
[0001] This application is a divisional of pending U.S. patent application Ser. No. 10/889,440, filed Jul. 12, 2004, the entire disclosure of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] This invention relates to a filter cartridge and a method and apparatus for replacing the filter cartridge from a filter housing. Specifically, the invention includes a latch release that is used separately from the filter cartridge to enable installation of a new, replacement filter cartridge.
[0003] Filter assemblies are used for many applications such as for various fluid systems of an automobile. The filter assemblies, for example, are used to filter fuel, air, oil and transmission fluid. Typical filter assemblies use many disposable components such as housings, valves and seals that add to the cost of the filter assembly. Furthermore, these components of the filter assembly should be properly disposed of to minimize the environmental impact. Disposal can be difficult and costly.
[0004] It is desirable to reduce the cost and environmental impact associated with replacement of the filter assembly. One solution has been to provide a permanent filter housing that is mounted to a portion of the vehicle. The housing has a cover that is removable to receive a replacement filter cartridge. The filter cartridge typically only includes opposing end caps and a filter element retained between the end caps. The filter cartridge is replaced at desired intervals.
[0005] Some filter assemblies using permanent housings incorporate a latch that prevents reinstallation of the cover unless a particular replacement filter cartridge is used. The particular filter cartridge uses two distinct end caps. The particular filter cartridge must be installed into the filter housing into a particular orientation. One end cap has features integrated with it that cooperates with the latch permitting the cover to be reinstalled.
SUMMARY OF THE INVENTION
[0006] The invention relates to a filter cartridge and latch release that may be packaged with one another for use in replacing a used filter cartridge in a filter assembly. In one example embodiment, the filter cartridge includes opposing end caps that are substantially the same as one another. The end caps have central holes. The filter cartridge is inserted into a filter assembly housing, which includes a latch that prevents a cover from being installed onto the filter assembly housing over the filter cartridge until the latch is deactivated.
[0007] The latch release, which is a separate component from the filter cartridge, is arranged relative to the filter cartridge to cooperate with the latch to enable the cover to be reattached to the filter assembly housing. The latch includes tabs that align with features of the latch and extend through the central hole of an exposed end cap to cooperate with the latch.
[0008] 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
[0009] FIG. 1 is a cross-sectional view of a filter assembly with an inventive filter cartridge and latch release, with a latch in an unlatched position.
[0010] FIG. 2 is a cross-sectional view of a bypass valve and latch of the filter assembly shown in FIG. 1 in the latched position.
[0011] FIG. 3 is a top elevational view of the bypass valve and latch shown in FIG. 2 .
[0012] FIG. 4 is a bottom perspective view of the inventive filter cartridge and latch release.
[0013] FIG. 5 is a top perspective view of the filter cartridge and latch release shown in FIG. 4 .
[0014] FIG. 6 is a cross-sectional view of the inventive latch release.
[0015] FIG. 7 is an exploded perspective view of the filter assembly with the bypass valve and latch in the latched position shown in FIG. 2 prior to installation of the inventive filter cartridge.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0016] An example filter assembly 10 is shown in FIG. 1 in cross-section. The filter assembly 10 includes a housing 12 having a body 14 providing a cavity 16 . A cover 18 is removably secured to the body 14 to provide access to the cavity 16 when desired. In the example shown, the cover 18 is threadingly secured to the body 14 . The cover 18 includes a feature at its exterior to facilitate removal of the cover 18 from the body 14 , such as a hexagonal protrusion for receiving a wrench.
[0017] An inventive filter cartridge 20 is arranged within the cavity 16 for filtering a fluid flowing through the cavity 16 . The housing 12 includes an inlet side 22 and an outlet side 24 respectively arranged at an exterior and interior of the filter cartridge 20 . Fluid is provided to the inlet side 22 through an inlet 26 at a base of the body 14 . Fluid exits the outlet side 24 through an outlet 28 at the base of the body 14 . Arrows F indicate fluid flow through the filter assembly 10 . However, fluid flow may be the reverse of the direction indicated, and the inlet and outlet 26 and 28 may be provided elsewhere on the housing 12 .
[0018] The housing 12 includes a center tube 30 extending through a central opening in the filter cartridge 20 . The center tube 30 is in fluid communication with the outlet side 24 and outlet 28 . The center tube 30 provides support for the filter cartridge 20 , as is known in the art, and may include apertures at various locations to permit fluid flow to an interior of the center tube 30 .
[0019] A bypass valve 32 is slidably received by the center tube 30 and is movable along an axis A. The bypass valve 32 is urged to a closed position (shown in FIG. 1 ) by a bypass valve spring 34 . The bypass valve 32 moves to an open position to permit fluid to flow from the inlet side 22 directly into the center tube 30 if the filter cartridge 20 becomes clogged. The bypass valve spring 34 has a spring rate selected to enable the bypass valve 32 to open at a predetermined pressure corresponding to a clogged filter cartridge 20 .
[0020] A latch 36 is slidably received by the bypass valve 32 and center tube 30 and is movable along the axis A. The bypass valve spring 34 is supported between the bypass valve 32 and an upper portion of the latch 36 , which is known. The latch 36 is shown in an unlatched position in FIG. 1 , which permits the cover 18 to be fully installed onto the body 14 .
[0021] Referring to FIGS. 1 and 2 , a latch spring 38 is arranged between a shoulder 42 of the center tube 30 and a head 44 of the latch 36 . The latch spring 38 biases the bypass valve 32 and latch 36 upward to a latched position, which is shown in FIG. 2 . The bypass valve 32 includes downwardly depending first legs 46 that are arranged in alternating relationship to second legs 47 of the latch 36 . The center tube 30 includes a radially extending ledge 48 . The first legs 46 extend outward and into engagement with an inner surface 51 of the center tube 30 which is above the ledge 48 , as shown in FIG. 2 . The latch 36 includes a radial flange 50 that is arranged radially inward of ends of the first legs 46 to urge the first legs 46 into engagement with the inner surface 51 when the bypass valve 32 and latch 36 are in the latched position. In the latched position, the bypass valve 32 is prevented from being inserted back into the center tube 30 unless the latch 36 is released, which will be discussed in more detail below.
[0022] Referring to FIG. 3 , an upper portion of the bypass valve 32 includes alternating apertures 52 . The latch 36 includes protrusions 54 that extend into the apertures 52 . Engagement and downward movement of the protrusions 54 moves the radial flange 50 out of engagement with the ends of the first legs 46 so that the first legs 46 disengage from inner surface 51 and are permitted to move inward and downward into the center tube 30 , past the ledge 48 , to the unlatched position.
[0023] As shown in FIGS. 4-6 , filter cartridge 20 includes end caps 56 that are substantially similar so that the filter cartridge may be inserted into the cavity 16 with either end cap 56 first. In the example shown, the end caps 56 are identical to one another. Both end caps 56 include large central holes 58 with a gasket 60 arranged about a circumference of the holes 58 . The gasket 60 , for example, is constructed from a felt material. The end caps 56 include a generally U-shaped cross-section, which is best seen in FIG. 1 . A filter element 62 is retained between the end caps 56 in any suitable manner, for example, using an adhesive material, which is well known in the art.
[0024] Referring to FIGS. 4-6 , the inventive filter cartridge 20 cooperates with a separate latch release 40 that is used to engage the protrusions 54 to move the latch 36 axially downward and into the center tube 30 . The example latch release 40 is a disc-shaped body.
[0025] The latch release 40 includes an inner annular flange 68 providing an opening 64 permitting fluid to flow from the inlet side 22 to the bypass valve 32 . An end 70 of the inner annular flange 68 engages a surface 72 of the bypass valve 32 to prevent fluid flow passed the bypass valve 32 when in the closed position.
[0026] The latch release 40 also includes an outer annular flange 66 on the same side as the inner annular flange 68 . The outer annular flange 66 engages an inner wall 61 of the adjacent, exposed end cap 56 to provide a seal with the end cap 56 . The gasket 60 also seals with the end cap 56 . The inner wall 61 of the opposite end cap 56 engages an outer surface of the center tube 30 or another feature of the housing 12 , which is best shown in FIG. 1 .
[0027] The latch release 40 also includes multiple arcuate holes 82 to permit fluid flow past the latch release 40 .
[0028] The latch release 40 includes tabs 74 extending from the latch release 40 on a side opposite the outer and inner annular flanges 66 and 68 , in the example shown, to engage the protrusions 54 . In the example shown, the tabs 74 extend radially outwardly from the inner annular flange 68 in a star-shaped configuration. However, the tabs 74 may be of any number and of any suitable configuration.
[0029] In the example shown, the latch release 40 includes retaining members 76 that cooperate with the cover 18 to secure the latch release 40 to the cover 18 . The retaining members 76 are prongs that cooperate with an annular recess 80 of an aperture 78 in an underside of the cover 18 , which is shown in FIGS. 1 and 7 . The latch release 40 may be snapped to the cover 18 using the retaining member 76 and annular recess 80 .
[0030] In operation, the cover 18 is removed from the body 14 at a desired interval to provide access to the cavity 16 so that the filter cartridge 20 may be replaced. Once the used filter cartridge 20 is removed, the bypass valve 32 and latch 36 automatically extend to a latched position, as shown in FIGS. 2 and 7 , under the biasing force of latch spring 38 . The inventive filter cartridge 20 is placed over the center tube 30 so that one end cap 56 is in sealing engagement with the outer surface 63 . Since the end caps 56 are the same, the inventive filter cartridge 20 may be inserted into the cavity 16 with either end cap 56 inserted first.
[0031] Next, the latch release 40 is installed onto the exposed end cap 56 . The gasket 60 seals against the latch release 40 and the outer annular flange 66 seals against the inner walls 61 of the exposed end cap 56 . The latch release 40 is aligned so that the tabs 74 engage the protrusions 54 . Now, downward movement of the latch release 40 moves the latch 36 downward to disengage the radial flange 50 from the first legs 46 . The cover 18 can then be threadingly secured to the body 14 . The retaining members 76 will snap into engagement with the annular recess 80 upon complete installation of the cover 18 onto the body 14 . Subsequent removal of the cover 18 will allow removal of both the latch release 40 and the filter cartridge 20 from the cavity 16 .
[0032] Alternatively, the latch release 40 can be installed onto the cover 18 and then the cover 18 can be threadingly secured to the body 14 after installation of the filter cartridge 20 . Rotation of the cover 18 will align the tabs 74 with the protrusions 54 . The tabs 74 will be retained within the apertures 52 thereby maintaining alignment with the protrusions 54 during additional rotation of the cover 18 during reinstallation.
[0033] The latch release 40 and end caps 56 are preferably constructed from a plastic material capable of withstanding the fluid environment to which the latch release 40 and end caps 56 are exposed. The filter element 62 is preferably a pleated paper element. The latch release 40 , end caps 56 and filter element 62 can be easily disposed of, such as by low temperature incineration, in an environmentally friendly manner.
[0034] The latch release 40 and filter cartridge 20 are preferably sold as a kit to customers. In instances when such a kit has already been used with the housing 12 , the old latch release 40 may be reused and the new latch release 40 may be recycled or vice versa.
[0035] 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. | A separate filter cartridge and latch release are used to replace a used filter cartridge in a filter assembly having a latch. In one example, the filter cartridge includes opposing end caps that are substantially the same as one another. The end caps have central holes. The filter cartridge is inserted into a filter assembly housing in which the latch prevents a cover from being installed onto a filter assembly housing until the latch is deactivated. The latch release is arranged relative to the filter cartridge to cooperate with the latch to enable the cover to be reattached to the filter assembly housing. The latch release includes tabs that align with features of the latch and extend through the central holes to cooperate with the latch. The latch release is removably secured to the cover and the filter cartridge. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/620,104 filed Oct. 19, 2004, which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates generally to a method for producing ceramic items utilizing ceramic stereolithography. More specifically, in one form the invention relates to a method for compensating for the anisotropic shrinkage of a ceramic item to produce dimensionally accurate ceramic stereolithography items.
[0003] Engineers and scientists are working in the field of stereolithography to develop additional processes for the production of components. In the area of non-ceramic stereolithography the scientific community is mainly concerned with shrinkage associated with the curing of the polymeric material. The types of materials used in non-ceramic stereolithography generally have very small shrink rates associated with post cure processing; such as by ultraviolet lamps.
[0004] In the area of ceramic stereolithography, there presently does not appear to be significant developmental activity going on associated with the study of dimensional accuracy of sintered ceramic stereolithography items. An interest in producing dimensionally accurate parts through ceramic stereolithography provided motivation for the development of the present inventions. The present invention satisfies this need and others in a novel and unobvious way.
SUMMARY OF THE INVENTION
[0005] The present inventions are set forth literally in the claims. The invention generally can be summarized as a method for compensating for the anisotropic shrinkage of a ceramic item when it is sintered.
[0006] One object of the present invention is to provide a unique method for producing a ceramic item.
[0007] Related objects and advantages of the present invention will be apparent from the following description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is an illustrative view of one form of an item being fabricated by a stereolithography process.
[0009] FIG. 2 is an illustrative view of the layer built item of FIG. 1 .
[0010] FIG. 3 is an illustrative top plan view of a portion of one of the layers of the item of FIG. 2 .
[0011] FIG. 4 is a perspective view of one embodiment of a shrinkage measurement test item.
[0012] FIG. 5 is a flow chart illustrating one embodiment of a system for creating a build file that determines how the item is built.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0013] For purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.
[0014] The general field of ceramic stereolithography is believed known to those of ordinary skill in the art. More specifically, ceramic stereolithography utilizes a photo-polymerizable resin containing ceramic particles that solidifies when exposed to an appropriate energy dose. The present invention contemplates that the photo-polymerizable material including ceramic particles can be described in many ways including, but not limited to filled and loaded. In one form of the present invention the photo-polymerizable material includes ceramic particles within a range of 35% to 65% by volume; however other relationships are contemplated herein.
[0015] The photo-polymerizable ceramic resin after being dosed with energy forms a green state ceramic item. The green state ceramic item is subjected to a burning off act to remove the photo-polymer and then a sintering act is applied to the ceramic material. During the sintering of the ceramic material there is a volumetric change in the item. Further, the inventors have recognized that there is generally very little volumetric change occurring during the burning off act of the photo-polymer. In one form ceramic stereolithography is accomplished in a machine adapted for stereolithography operations and available from 3D Systems of Valencia, Calif. However, the present inventions are applicable with virtually any type of apparatus or techniques for producing an item by stereolithography. Further, information related to selective laser activation and/or stereolithography is disclosed in U.S. Pat. Nos. 5,256,340, 5,556,590, 5,571,471 and in pending U.S. patent application Ser. No. 10/462,168, which are all incorporated herein by reference.
[0016] With reference to FIG. 1 , there is illustrated one embodiment of an item 45 being formed by a ceramic stereolithography process. Ceramic stereolithography as utilized herein should be broadly construed and includes the utilization of ceramic material within a photo-polymerizabele resin. The term item is intended to be read broadly and includes, but is not limited to, molds, parts, components and/or subcomponents. Item 45 is merely illustrative and is shown being formed by the photo-polymerization of the ceramic filled resin into layers (e.g. 50 , 51 , 52 , 53 ) of ceramic particles that are held together by a polymer binder. The reader should understand that there is no intention herein to limit the present application to any particular number of layers unless specifically provided to the contrary.
[0017] Stereolithography apparatus 500 is illustrated in a simplified manner to facilitate the explanation of one method of making ceramic item 45 . In one form the formation of the layers (e.g. 50 - 53 ) utilizes a leveling technique to level each of the layers of photo-polymerizable ceramic filled resin prior to receiving a dose of energy. The present application contemplates the following techniques to level the resin: ultrasonic processing; time delay; and/or mechanically assisted sweep such a wiper blade. However, the present application also contemplates an embodiment that does not utilize express techniques for leveling each of the layers prior to receiving a dose of energy. A three dimensional coordinate system including a first axis, a second axis and a third axis is utilized as a reference for the item being fabricated. In one form the three dimensional coordinate system is a Cartesian coordinate system. More preferably, the Cartesian coordinate system includes an X, Y and Z axis utilized as a reference for the item being fabricated correspond to the axis of the stereolithography apparatus. However, other three dimensional coordinate systems are contemplated herein, including but not limited to polar, cylindrical, spherical. The text will generally describe the present invention in terms of a Cartesian coordinate system, however it is understood that it is equally applicable to other three dimensional coordinate systems.
[0018] In one form stereolithography apparatus 500 includes a fluid/resin containment reservoir 501 , an elevation-changing member 502 , and a laser 46 . The reservoir 501 is filled with a quantity of the photocurable ceramic filled resin from which the item 45 is fabricated. Item 45 is illustrated being fabricated in layer by layer fashion in the stereolithography apparatus 500 in the direction of axis Z; which is referred to as the build direction. The item 45 is built at a build orientation angle as measured from the axis Z. The build orientation angle illustrated is zero °; however there is no limitation intended herein regarding the build orientation angle as other build orientation angles are fully contemplated herein. The three dimensional coordinate system is aligned with the build orientation angle. More specifically, in a preferred form the three dimensional coordinate system of the item being fabricated and the stereolithography apparatus' coordinate system are coextensive.
[0019] With reference to FIG. 2 , there is illustrated an enlarged view of a portion of the item 45 . The item 45 includes a plurality of cured layers 50 , 51 , 52 which define a portion of the item. The present application contemplates that the term cured includes partially or totally cured layers. The layers are contemplated as having the same or different shapes, may be solid or contain voids or holes, may have the same or differing thickness as required by the design parameters. In one form the cured layers have a thickness within a range of about 0.001 to about 0.008 inches. In another form each of the layers has a thickness of about 0.002 inches. However, other cured layer thickness are contemplated herein.
[0020] With reference to FIG. 3 , there is set forth a purely illustrative plan view of a portion of a layer 53 . Layer 53 represents a portion of a layer formed in a stereolithography apparatus 500 that utilized a wiper blade moved in the direction of axis Y to level the photo-polymerizable ceramic filled resin prior to receiving a dose of energy. The wiper blade interacts with the photo-polymerizable ceramic filled material and affects the homogeneity in at least two dimensions. The inventors have discovered that the shrinkage in the item associated with a subsequent sintering act is anisotropic in the three directions; for example the X, Y and Z directions. Anisotropic shrinkage can be considered to occur when isotropic shrinkage is not sufficient to keep the sintered item within a predetermined geometric tolerance. In the discussion of the anisotropic shrinkage relative to the X, Y and Z axis the Z axis represents the build direction and the Y axis represents the direction of the movement of the wiper blade. The inventors have determined that shrinkage in the Z direction (build direction) is greater than in the X and Y directions. Factors to consider when evaluating the shrinkage are the solid loading in the photo-polymerizable resin, the resin formulation, the build style and orientation and how the item is sintered.
[0021] With reference to FIG. 4 , there is illustrated one embodiment of a shrinkage measurement test model 300 . In one form the shrinkage measurement test model 300 is created as a solid body model and then generated as an STL file. In one form the item is oriented such that the back corner represents the origin of a Cartesian coordinate system X, Y, Z. The vertical direction of the STL being aligned with the Z axis and the two sides 301 and 302 being aligned with the X and Y axis respectively. The item is than built in a stereolithography apparatus with the Cartesian coordinate system of the item aligned with the coordinate system of the stereolithography apparatus. The present invention can be utilized with any suitable file format and/or hardware.
[0022] The shrinkage measurement test model 300 in the green state is then subjected to a comprehensive inspection to quantify dimensions of the item. The measurements taken during inspection can be obtained with known equipment such as, but not limited to calipers and/or coordinate measuring machines. In one form the shrinkage measurement test model has been designed so that all of the inspection dimensions line up along the X, Y and/or Z axis. The item is then subjected to a firing act to burn off the photo-polymer and sinter the ceramic material. The comprehensive inspection is repeated to quantify the dimensions of the item after being sintered.
[0023] The measured values from the comprehensive inspection after firing are than compared with the inspection values from the green state item. In one form the comparison is done by plotting the measured values of the fired item against the measured values from the green state item. A least squares analysis is performed to obtain a linear equation. The resulting slope of the equations is the shrinkage factors for each of the X, Y and Z direction/dimensions. The shrinkage for each of the X, Y and Z directions/dimensions are applied to one of the STL file or the solid body model to expand the dimensions in the respective directions of the coordinate system. The process will modify one of the STL file or the solid body model in the directions of the coordinate system to account for the anisotropic shrinkage of the item. In one non-limiting example the shrinkage factors to account for shrinkage are 118%, 115% and 120% in the X, Y, Z direction respectively for an item having a length of about two inches. The present application contemplates a wide variety of shrinkage factors and is not limited in any manner to these factors unless specifically provided o the contrary.
[0024] The application of the present invention enables the production of sintered ceramic items having substantially conformity with the item's design parameters. In one form the dimensional accuracy of the sintered ceramic item to the design parameters is within a range of 0.0% to 1.5% and in another form the dimensional accuracy is within a range of 0.0% to 0.5%. Further, the present invention is also applicable to form sintered ceramic items in either near net shape or net shape. Additionally, other degrees of dimensional accuracy are contemplated herein.
[0025] In an alternate form the comparison utilized to calculate the shrinkage factors of the shrinkage measurement test model is between the inspection values of the fired test model and the dimensional design values from the solid body model. The process as described above is then continued to find the shrinkage factors for the X, Y and Z dimensions/directions.
[0026] With reference to FIG. 5 , there is illustrated one non-limiting embodiment of a system for creating a build file 1005 that determines how the item 45 is created in the stereolithography apparatus. This process is representative of a technique that can be utilized to produce the build file, but the present application is not intended to be limited to the one embodiment in FIG. 5 unless specifically stated to the contrary. In act 1000 data defining parameters of the item are collected and processed to define a specification for the item design. The data from act 1000 is utilized in act 1001 to construct an item model using, for example, a computer modeling system. In one embodiment the computer modeling system creates an electronic model such as but not limited to a solid body model. However, other modeling systems are contemplated herein. The item model from act 1001 is then processed in a modified item model act 1002 to create a model of the item taking into account the anisotropic shrinkage. While the present application discusses the process in terms of modification of the item model it is understood that the same type of modification is applicable to the STL/STC files to create a modified item file. The modified item act 1002 utilizes an X shrinkage factor, a Y shrinkage factor and a Z shrinkage factor. The shrinkage factors are used to increase the respective underlaying dimensions to a modified dimension. The X, Y and Z shrinkage factors will be applied so that they correspond to the coordinate system of the stereolithography apparatus.
[0027] In one form a conversion act 1003 is utilized to convert the modified item model, produced in act 1002 to a file format, such as STL or SLC. Next, the file from act 1003 is processed in act 1004 to create discrete two-dimensional slices appropriate for drawing the layers of the item and any required supports. In act 1005 the build file is completed, which will be utilized to drive the energy source of the stereolithography apparatus and produce the green ceramic item.
[0028] In one form the ceramic filled resin comprises a sinterable ceramic material, a photocurable monomer, a photoinitiator and a dispersant. The ceramic filled resin is adapted for use in stereolithography to produce a green ceramic item. In one form the filled resin is prepared by admixing the components to provide a filled resin having viscosity within a range of about 300 centipoise to about 3,500 centipoise at a shear rate of about 0.4 per second; in another form the filled resin has a viscosity of about 2,500 centipoise at a shear rate of about 0.4 per second. However, the present application contemplates filled resins having other viscosity values.
[0029] The loading of ceramic material within the resin is contemplated within a range of 35% to 65% by volume. Another form of the ceramic loading within the resin is contemplated as being about 50.3% by volume. In one preferred resin the ceramic loading has the volume percent of ceramic material substantially equal to the weight percent of ceramic material within the resin. However, resins having other ceramic loadings are fully contemplated herein. More specifically, the present application contemplates that the volume percent of the ceramic material in the resin may be equal to the weight percent of the ceramic material in the resin or that the volume percent of the ceramic material in the resin may be unequal to the weight percent of the ceramic material in the resin. The sinterable ceramic material can be selected from a wide variety of ceramic materials. Specific examples include, but are not limited to, alumina, yttria, magnesia, silicon nitride, silica and mixtures thereof.
[0030] In one example alumina is selected as the sinterable ceramic material. Alumina can be provided as a dry powder having an average particle size suitable for sintering to provide an item having the desired characteristics. In one form the powdered alumina has an average particle size within a range of 0.1 microns to 5.0 microns. In another form the powdered alumina is selected to have an average particle size within a range of 0.5 microns to 1.0 microns. However, other particle sizes for the alumina material are contemplated herein.
[0031] The monomer is selected from any suitable monomer that can be induced to polymerize when irradiated in the presence of a photoinitiator. Examples of monomers include acrylate esters and substituted acrylate esters. A combination of two or more monomers may be used. Preferably at least one of the monomers is a multifunctional monomer. By multifunctional monomer it is understood that the monomer includes more than two functional moieties capable of forming bonds with a growing polymer chain. Specific examples of monomers that can be used with this invention include 1,6-hexanediol diacrylate (HDDA) and 2-phenoxyethyl acrylate (POEA). In one form the photocurable monomers are present in an amount between about 10 wt % to about 40 wt %, and in another form about 10 wt % to about 35 wt %, and in yet another form about 20 wt % to 35 wt % based upon the total weight of the filled resin. However, the present application contemplates other amounts of monomers.
[0032] The dispersant is provided in an amount suitable to maintain a substantially uniform colloidal suspension of the alumina in the filled resin. The dispersant can be selected from a wide variety of known surfactants. Dispersants contemplated herein include, but are not limited to, ammonium salts, more preferably tetraalkyl ammonium salts. Examples of dispersants for use in this invention include, but are not limited to: polyoxypropylene diethyl-2-hydroxyethyl ammonium acetate, and ammonium chloride. In one form the amount of dispersant is between about 1.0 wt % and about 10 wt % based upon the total weight of the ceramic within the filled resin. However, the present application contemplates other amounts of dispersants.
[0033] The initiator is selected from a number of commercially available photoinitiators believed known to those skilled in the art. The photoinitiator is selected to be suitable to induce polymerization of the desired monomer when irradiated. Typically the selection of a photoinitiator will be dictated by the wavelength of radiation used to induce polymerization. Photoinitiators contemplated herein include, but are not limited to benzophenone, trimethyl benzophenone, 1-hydroxycyclohexyl phenyl ketone, isopropylthioxanthone, 2-methyl-1-[4 (methylthio)phenyl]-2-morpholinoprophanone and mixtures thereof. The photoinitiator is added in an amount sufficient to polymerize the monomers when the filled resin is irradiated with radiation of appropriate wavelength. In one form the amount of photoinitiator is between about 0.05 wt % and about 5 wt % based upon the total weight of the monomer within the filled resin. However, other amounts of photoiniators are contemplated herein.
[0034] In an alternate form of the ceramic filled resin a quantity of a nonreactive diluent is substituted for a quantity of the monomer. In one form the amount of substituted nonreactive diluent is equal to between about 5% and about 20% (by weight) of the monomer in the resin. However, the present application contemplates that other amounts of non-reactive diluents are considered herein. An illustration of a given ceramic resin composition requires 100 grams of a monomer that in the alternate form will replace about 5-20 wt % of the monomer with a nonreactive diluent (i.e. 95-80 grams of monomer+5-20 grams of nonreactive diluent). The nonreactive diluent includes but is not limited to a dibasic ester or a decahydronaphthalene. Examples of dibasic esters include dimethyl succinate, dimethyl glutarate, and dimethyl adipate, which are available in a pure form or a mixture.
[0035] The filled resin is prepared by combining the monomer, the dispersant and the sinterable ceramic to form a homogeneous mixture. Although the order of addition is not critical to this invention typically, the monomer and the dispersant are combined first and then the sinterable ceramic is added. In one form the sinterable ceramic material is added to the monomer/dispersant combination in increments of about 5 to about 20 vol. %. Between each incremental addition of the ceramic material, the resulting mixture is thoroughly mixed by any suitable method, for example, ball milling for about 5 to about 120 minutes. When all of the sinterable ceramic material has been added, the resulting mixture is mixed for an additional amount of time up to 10 hours or more. The photoinitiator is added and blended into the mixture.
[0036] With reference to Table I there is set forth one example of an alumina filled resin. However, the present application is not intended to be limited to the specific composition set forth below unless specifically stated to the contrary.
vol wt/g cc wt % vol % Alumina 1980 500 78.2 48.0 Monomer 510 500 20.1 48.0 Dispersant 39.6 38.8 1.56 3.73 Photoinitiator 2.55 2.32 0.101 0.223 Total 2532 1041 100% 100%
[0037] In one form the green ceramic item is sintered to a temperature within a range of 1100° C. to 1700° C. The present invention contemplates other sintering parameters. Further, the present invention contemplates sintering to a variety of theoretical densities, including but not limited to about 60% of theoretical density. The density of the sintered material is preferably greater than sixty percent of the theoretical density, and densities equal to or greater than about ninety-four percent of the theoretical density are more preferred. However, the present invention contemplates other densities.
[0038] The present application contemplates the utilization of a three dimensional coordinate system as a reference for an item being fabricated from the photo-polymerizable ceramic filled resin. As discussed above the inventors have discovered that the shrinkage of the item in a subsequent sintering act is anisotropic in the three directions. Therefore, in one form of the present invention there are utilized three unequal scaling factors to take into consideration the respective shrinkage in the dimensions of the item in all three directions. In another form of the present invention there are utilized only two unequal scaling factors to account for the respective shrinkage in the dimensions of the item in all three directions; that is the dimensions in two of the three directions are adjusted by scaling factors having the same value.
[0039] While the inventions have been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected. It should be understood that while the use of the word preferable, preferably or preferred in the description above indicates that the feature so described may be more desirable, it nonetheless may not be necessary and embodiments lacking the same may be contemplated as within the scope of the invention, that scope being defined by the claims that follow. In reading the claims it is intended that when words such as “a,” “an,” “at least one,” “at least a portion” are used there is no intention to limit the claim to only one item unless specifically stated to the contrary in the claim. Further, when the language “at least a portion” and/or “a portion” is used the item may include a portion and/or the entire item unless specifically stated to the contrary. | A manufacturing method for producing ceramic item from a photocurable ceramic filled material by stereolithography. The method compensates for the anisotropic shrinkage of the item during firing to produce a dimensionally accurate item. | 1 |
RELATED APPLICATION DATA
This application claims priority of U.S. Provisional Application No. 60/867,613 filed on Nov. 29, 2006, which is incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
The present invention relates to medical registration of anatomical structures using markers.
BACKGROUND OF THE INVENTION
Prior to surgery, it is often necessary to register an anatomical structure within a medical workspace, i.e., to determine a spatial location of the structure or of a partial region of the structure, such as a three-dimensional position of characteristic points or landmarks on the structure. These characteristic points or landmarks can be used in a hip operation, for example, to determine the spatial location of characteristic planes. From the location of the characteristic planes, the inserted position of a hip joint cavity can be determined.
If, in a hip operation, recordings are taken of the pelvis using a C-arm, then it is difficult or impossible to identify a characteristic or unique contour of the pelvis due to the different types of tissues and operating instruments that may be present. It also can be difficult to detect a contour or characteristic point since the anatomical structures are different for different patients, such that when registering the anatomical structure inaccuracies may be introduced. This can cause problems during or after surgery.
A method and device for registering a pelvis are known from WO 2005/084541, wherein a pointer comprising trackable markers that are detectable by a tracking system is used for acquiring points.
SUMMARY OF THE INVENTION
In a method for registering a structure, such as an anatomical structure, for example, it is possible to detect a contour in the structure itself or in a three-dimensional model of the structure and/or one or more landmarks. These contours and/or landmarks can be detected using at least two two-dimensional recordings obtained from an imaging method, and the structure can be registered by fixing one or more markers, such as radio-opaque markers, for example, on or in the structure (e.g., inserting the markers into the structure). The markers can be detected or identified by the imaging method used to obtain the two-dimensional recordings.
The marker or markers, for example, can be inserted into a bone or into the surface of the bone of a structure (e.g., a pelvis), preferably at a characteristic point or characteristic line, such that it is no longer necessary to detect the characteristic point or landmark when the corresponding marker or a group of markers is recorded. The positions of the markers in the at least two two-dimensional recordings of the structure can be rear-projected, and the intersection points resulting from the rear-projection can be compared with a three-dimensionally detected structure obtained using a CT method. The respective marker positions then can be matched so as to register the structure.
It is, however, not absolutely necessary to record a model and/or pre-operative image data sets. Even during the operation, the marker positions alone can define characteristic planes and, for example, planes that define the location or orientation of the object such as for example the mid-sagittal plane or the frontal pelvis plane, straight lines or points such as for example spinal points, in registered 2D images, which can be sufficient for the operation. Additionally, an image data set such as a CT data set, for example, also can be registered using the previously inserted marker positions.
In particular, when, prior to performing the method in accordance with the invention, the structure to be registered has been recorded with attached or inserted markers, then, in order to generate a three-dimensional computer model of the structure with the inserted markers, a known matching method can quickly and easily ascertain how the markers, which are visible on the at least two two-dimensional recordings of the structure, are assigned to the three-dimensional computer model. From this, it is then possible to ascertain the position of one or more characteristic points or landmarks that have a locational relationship with respect to the markers that are known from the three-dimensional recording of the structure. It is thus possible to determine known geometries, lines or points of a structure by means of two fluoroscopic images, for example, without using a pointer or the like to identify the characteristic points or landmarks on the structure.
If, for example, a pelvis is to be registered, then the pelvic contour can be detected in 2D images of the patient (which may be obtained intra-operatively) from which characteristic planes, for example, can be calculated as additional information. The 2D images can be registered via a reference on the patient, such as for example a reference star fixed on the patient, and wherein the fluoroscopic kit on the C-arm is already or can be automatically registered. Additional information, such as for example body planes obtained from the pelvic contour in the registered images, also can be used for orientating the implant components.
If a calibrated recording method or a calibrated recording device (e.g., a calibrated C-arm to which a number of markers are attached that can be identified by a navigation system) is used to generate the at least two two-dimensional recordings of the structure, then it is possible to determine or calculate the three-dimensional positions of the markers from the two-dimensional marker positions in the recordings or images, for example by rear-projection. This can be accomplished, for example, based on the registered recordings or fluoroscopic images taken from at least two different viewing directions, and in which markers connected to the structure are visible. The three-dimensional positions of the markers can thus be spatially ascertained. Further, and after a matching method using a previously obtained three-dimensional recording of the structure, the position and orientation of the three-dimensional structure can be spatially determined from the marker positions ascertained in this way, thus enabling the structure to be automatically registered. Using the method described herein, it is thus possible to easily register a structure, since only the position of one or more markers are ascertained. It is not necessary to detect a contour, which for example changes in accordance with the direction of the respective two-dimensional recording, and match it to a three-dimensional computer model.
The at least two two-dimensional recordings of the structure can be obtained from different directions using a calibrated x-ray source and a corresponding calibrated detector, such as for example a calibrated C-arm, wherein two transformation matrices of the respective x-ray recordings are known. The coordinates of the images and also the information in the images can be transformed by these two matrices into a patient coordinate system. In the patient coordinate system, the transformed information can be matched with a three-dimensional computer model obtained from a previously obtained CT or MR recording, for example.
The method described herein, for example, also can be performed using only one marker, if one or more landmarks are acquired by other methods, for example, via a pointer.
Objects made of tantalum, such as for example tantalum spheres, preferably having a diameter of less than 1 mm, are preferably used as markers and inserted into the bone or surface of the bone. Using tantalum markers that are inserted into a bone and localized by means of a pointer is known from WO 97/32522. Equally, cuboids or other edged objects which ensure a good anchoring in the bone, for example, also can be used as markers. A marker that is fixed in the bone by rotation or some other movement is also conceivable.
Also provided herein is a computer program which, when it is loaded onto a computer or is running on a computer, performs the method as described herein, and a program storage medium or computer program product comprising such a program.
A device for registering an anatomical structure comprises a recording unit for generating at least two two-dimensional mappings of the structure using recordings from different directions, such as for example a C-arm. The C-arm can be connected to a computational unit that has a three-dimensional model of the structure to be registered stored in memory (e.g., in a database). This three-dimensional model of the structure, for example, may have been generated by a CT scanner connected to the computational unit. The device also can comprise a navigation system for detecting the position of markers that, for example, reflect or emit visible or infrared light. One or more markers can be attached to the recording device, such as for example to the C-arm, such that calibrated recordings (e.g., calibrated fluoroscopic shots) can be generated and transmitted to the computational unit. The computational unit then can register the structure from the calibrated recordings of the structure and the three-dimensional model of the structure using the method described herein. The computational unit also can assign the position and orientation of the three-dimensional model to the actually present structure recorded from different directions by the recording device, such that ideally, the model and the actually present structure completely match.
BRIEF DESCRIPTION OF THE DRAWINGS
The forgoing and other features of the invention are hereinafter discussed with reference to the drawings.
FIG. 1 is a diagram of an exemplary injection instrument for inserting markers.
FIG. 2 is a cross-sectional view of an exemplary bone, together with the injection instrument of FIG. 1 .
FIG. 3 is an x-ray recording of an exemplary femur comprising inserted tantalum markers.
FIGS. 4A and 4B illustrate the mapping of a tantalum sphere in the spina iliaca.
FIG. 5 is a flow diagram illustrating an exemplary method in accordance with the invention.
FIG. 6 is a block diagram of an exemplary computer system that can be used to implement the method described herein.
DETAILED DESCRIPTION
FIG. 1 illustrates an exemplary injection device for inserting spherical tantalum markers into a bone. The injection device includes a hollow drill 1 having an opening 1 a at its tip. One or more tantalum spherule 5 ( FIG. 2 ) can be dispensed through the opening 1 a once the drill 1 has drilled a recess or hole into a bone 6 (e.g., to a depth of about 3 mm). The drill 1 can be detachably fixed on a housing 2 , which includes a handle 3 and a trigger button 4 . The drill 1 can be rotated either by manually operating the handle 3 or by a motor provided in the housing 2 of the instrument. At the desired depth of penetration, the button 4 can be operated, which inserts the tantalum sphere 5 into the bone 6 .
FIG. 2 illustrates a cross-sectional view of the drill 1 penetrating an approximately 3 mm thick compact bone layer in order to insert the spherical tantalum marker 5 (which has a diameter of about 0.5 mm) into the bone 6 . A marker 5 inserted in this way sits securely in the bore formed in the bone 6 via a press or interference fit.
If, as shown in FIG. 2 , a number of tantalum markers 5 are inserted into the bone 6 , then these markers 5 can easily be identified in a two-dimensional x-ray image of the bone structure. Such a two-dimensional x-ray image is shown in the x-ray recording of the femur 7 in FIG. 3 . The coordinates of the centers of mass of the spherical markers 5 can be calculated and, when a number of calibrated x-ray recordings have been generated, the coordinates can be transformed into a patient coordinate system. If a number of markers 5 are present or if other characteristic points or landmarks on the structure are additionally acquired using known methods, such as for example acquiring points using a pointer, the anatomical structure can be registered as described herein.
FIGS. 4A and 4B show an enlarged representation of the mapping of a tantalum marker 5 in the spina iliaca from two different directions, wherein the position of the tantalum marker 5 in three-dimensional space can be determined from the two calibrated recordings shown in FIGS. 4A and 4B . This can be accomplished, for example, by rear-projecting the marker position ascertained in the two two-dimensional recordings. In hip surgery wherein the patient is positioned laterally, it is not possible to reach both sides of the patient with, for example, a mechanical pointer. However, it is possible to ascertain the position of the spina iliaca in the patient coordinate system, including both the accessible portion and the inaccessible healthy side (on which the patient is lying) from the two recordings shown in FIGS. 4A and 4B . Therefore, it is possible to register the pelvis from the landmark ascertained in this way together with another landmark which, for example, is likewise marked by tantalum markers 5 or acquired by means of a pointer.
FIG. 5 shows a flow diagram of an exemplary method in accordance with the invention. A three-dimensional model of the structure, such as for example a hip, is generated by means of a CT recording at block 10 , and the positions of the inserted markers are determined in the three-dimensional model at block 11 . At block 12 , calibrated fluoroscopic shots can be taken of the anatomical structure or pelvis from two different directions so as to obtain two two-dimensional x-ray recordings of the structure. The positions of the markers that are visible in the x-ray recordings are in turn ascertained at block 13 . A known matching method then can be performed at block 14 in order to orientate the three-dimensional model ascertained from the CT recording in three-dimensional space or in the patient coordinate system. The matching method can use the locational information ascertained from the fluoroscopic shots, such that at block 15 the three-dimensional model of the structure matches the actual structure, thus registering the structure or pelvis.
Moving now to FIG. 6 there is shown a block diagram of an exemplary computer 20 that may be used to implement the method described herein. The computer 20 may include a display 22 for viewing system information, and a keyboard 24 and pointing device 26 for data entry, screen navigation, etc. A computer mouse or other device that points to or otherwise identifies a location, action, etc., e.g., by a point and click method or some other method, are examples of a pointing device 26 . Alternatively, a touch screen (not shown) may be used in place of the keyboard 24 and pointing device 26 . The display 22 , keyboard 24 and mouse 26 communicate with a processor via an input/output device 28 , such as a video card and/or serial port (e.g., a USB port or the like).
A processor 30 , such as an AMD Athlon 64® processor or an Intel Pentium IV® processor, combined with a memory 32 execute programs to perform various functions, such as data entry, numerical calculations, screen display, system setup, etc. The memory 32 may comprise several devices, including volatile and non-volatile memory components. Accordingly, the memory 32 may include, for example, random access memory (RAM), read-only memory (ROM), hard disks, floppy disks, optical disks (e.g., CDs and DVDs), tapes, flash devices and/or other memory components, plus associated drives, players and/or readers for the memory devices. The processor 30 and the memory 32 are coupled using a local interface (not shown). The local interface may be, for example, a data bus with accompanying control bus, a network, or other subsystem.
The memory may form part of a storage medium for storing information, such as application data, screen information, programs, etc., part of which may be in the form of a database 36 . The database 36 may include data pertaining to a three-dimensional model of a structure to be registered. The storage medium may be a hard drive, for example, or any other storage means that can retain data, including other magnetic and/or optical storage devices. A network interface card (NIC) 34 allows the computer 20 to communicate with other devices.
Communicatively coupled to the computer 20 is a recording unit 38 , such as a a calibrated x-ray source and a corresponding calibrated detector (e.g., a calibrated C-arm). The recording unit 38 also can include a reference array 40 or the like attached thereto. The reference array 40 enables a spatial location of the recording unit to be ascertain by a navigation system 42 , for example.
A person having ordinary skill in the art of computer programming and applications of programming for computer systems would be able in view of the description provided herein to program a computer system 20 to operate and to carry out the functions described herein. Accordingly, details as to the specific programming code have been omitted for the sake of brevity. Also, while software in the memory 32 or in some other memory of the computer and/or server may be used to allow the system to carry out the functions and features described herein in accordance with the preferred embodiment of the invention, such functions and features also could be carried out via dedicated hardware, firmware, software, or combinations thereof, without departing from the scope of the invention.
Computer program elements of the invention may be embodied in hardware and/or in software (including firmware, resident software, micro-code, etc.). The invention may take the form of a computer program product, which can be embodied by a computer-usable or computer-readable storage medium having computer-usable or computer-readable program instructions, “code” or a “computer program” embodied in the medium for use by or in connection with the instruction execution system. In the context of this document, a computer-usable or computer-readable medium may be any medium that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. The computer-usable or computer-readable medium may be, for example but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, device, or propagation medium such as the Internet. Note that the computer-usable or computer-readable medium could even be paper or another suitable medium upon which the program is printed, as the program can be electronically captured, via, for instance, optical scanning of the paper or other medium, then compiled, interpreted, or otherwise processed in a suitable manner. The computer program product and any software and hardware described herein form the various means for carrying out the functions of the invention in the example embodiments.
Although the invention has been shown and described with respect to a certain preferred embodiment or embodiments, it is obvious that equivalent alterations and modifications will occur to others skilled in the art upon the reading and understanding of this specification and the annexed drawings. In particular regard to the various functions performed by the above described elements (components, assemblies, devices, compositions, etc.), the terms (including a reference to a “means”) used to describe such elements are intended to correspond, unless otherwise indicated, to any element which performs the specified function of the described element (i.e., that is functionally equivalent), even though not structurally equivalent to the disclosed structure which performs the function in the herein illustrated exemplary embodiment or embodiments of the invention. In addition, while a particular feature of the invention may have been described above with respect to only one or more of several illustrated embodiments, such feature may be combined with one or more other features of the other embodiments, as may be desired and advantageous for any given or particular application. | A method for registering an anatomical structure using at least one marker attached to the structure includes: obtaining a three-dimensional model of the structure via an imaging method; obtaining at least two two-dimensional recordings of the structure from different angles; and ascertaining a spatial position and location of the three-dimensional model or a position and location of the three-dimensional model in a patient coordinate system based on a matching method that uses the position of the at least one marker in the at least two two-dimensional mappings such that the three-dimensional model of the structure matches the structure. | 0 |
FIELD OF THE INVENTION
This invention relates to improvements in the automated control of electrolytic smelting cells for the production of aluminium.
BACKGROUND OF THE INVENTION
The control of electrolytic cells in the production of aluminium is influenced by both short term and long term process parameter changes. In the short term, bath superheat, alumina concentration and anode to cathode distance (ACD) need constant monitoring, while longer term control is required for metal depth and the composition and volume of the electrolyte in the cell. Operating abnormalities also require attention, such as sludging, anode effects and their frequency, and the short circuiting of the current between the anodes and the metal pad.
The complexity of the interrelationships between the dependent and independent variables in the smelting process are illustrated in Chapter 9 of "Aluminium Smelter Technology"-Grjotheim and Welch-Aluminium-Verlag, 1988, and this chapter provides a useful summary of the currently utilised control strategies. This summary and the proliferation of literature on the subject further illustrate the complexity of the problem and the absence of a strategy that provides a satisfactory level of control resulting in constantly high efficiency levels.
Numerous examples of control strategy proposals are also to be found in the patent literature. Recent examples include U.S. Pat. No. 4,654,129 Leroy which describes a process involving periods of over supply and under supply to maintain the alumina concentration in the cell within a narrow range by monitoring the rate of change of the resistance of the cell. This process relies for its success on the use of point feeding of alumina to the cell, and it is not therefore useful for cells without point feeders. Also, since in this strategy it is critical to maintain the alumina concentration within a narrow range, the strategy suffers if the concentration moves outside that range and it is often difficult to restore the system to its optimum operating conditions.
A similar control strategy is described in International Patent Application PCT/NO86/00017 (W086/050008) Aalbu et al. In common with the above U.S. patent, the strategy relies heavily on the rate of change of the resistance of the cell to monitor alumina concentration and does not have regard to other important parameters to control the heat and mass balance of the cell. The disclosure similarly does not address the strategy to be adopted during process events, such as alumina feeding, anode movements, anode setting and tapping.
U.S. Pat. Nos. 4,008,142 and 4,024,034 Doring et al, uses the concept of constant anode-cathode distance to adjust cell resistance according to the known or assumed electrochemical voltage breakdown. Anode-cathode distance adjustment is made in cases where current efficiency (by metal production measurement) is less than expected theoretically. Automatic adjustment of voltage/cell resistance in response to noise on the signal is also indicated. However, no attempt is made to calculate the heat or alumina balances or to make furnace adjustments on this basis, with the exception of adjustment of cell resistance on the basis of long term running metal production figures. This does not constitute a calculation of the energy balance or process energy requirement.
In U.S. Pat. No. 4,766,552 Aalbu et al, the resistance/alumina concentration curve is used to control alumina concentration on point feed cells. A linear model of the cell resistance variation is set up using the resistance slope as a parameter. By fitting the model to continuous resistance measurements, the slope is estimated. However, this strategy does not ensure that the resulting slope is related only to alumina concentration, in fact it assumes this one to one relationship. Anode movement is included in the fitted algorithm and other disturbances are filtered by reducing the gain of the fitting functions when they occur. This procedure is very complex and could be prone to error. In addition, the strategy does not attempt to maintain heat balance within the cell.
In U.S. Pat. No. 4,333,803 Seger and Haupin, a heat flux sensor is used to measure sidewall heat flow. Cell resistance is adjusted to maintain this at a predetermined value. However, this strategy:
1. does not guarantee that heat losses from other portions of the cell are under control (top, bottom);
2. does not react to changes inside the cell on a useful time scale (hours or within a day)--the cell can be significantly out of heat balance before an adjustment is made; and
3. does not provide information about the events/operations occurring in the electrolyte. These events are needed to close the overall energy balance--including the continuous changing process requirements--and to sense the condition of the liquid electrolyte which is where electrolysis is taking place. Effective bath resistivity sensing in the strategy disclosed here allows much faster response to a heat imbalance in the electrolyte.
Other control strategies are described in U.S. Pat. Nos. 3,969,669 Brault and Lacroise, 3,829,365 Chandhuri et al, 4,431,491 Bonny et al, 4,654,129 Leroy, 4,654,130 Tabereaux et al, 3,622,475 Shiver, 3,878,070 Murphy, 3,573,179 Dirth et al, 4,035,251 Shiver and 4,488,117 Seo. This list is by no means intended to be exhaustive.
A primary factor in reduction cell efficiency is the thermal state of the materials in the cell cavity. A control strategy directed at optimizing efficiency should therefore aim to maintain a thermal steady state in the cell. That is, the rate of heat dissipation from the cell cavity should be kept constant. If this is achieved in concert with stable bath and metal inventories, operational stability can be enhanced. The bath superheat will be constant; hence bath volume, chemistry and temperature will be stable due to the absence of ledge freezing or melting. Improved operational stability may allow a cell to be operated with better alumina feed control, at a lower bath ratio, and at a lower time averaged rate of heat loss. This will improve the process productivity.
A major difficulty in maintaining thermal steady state in a reduction cell is the discontinuous nature of various operations. The energy requirements of alumina feeding and dissolution can vary from minute-to-minute, particularly on breaker-bar cells. This is further exacerbated by the deliberate changes in feed rate required by many feed control techniques. Anode setting in pre-baked cells also introduces a large cyclic energy requirement. Other processes, such as bath additions, anode effects and amperage fluctuations further alter the short-term thermal balance of a cell. Currently available control systems do not address these fluctuating thermal requirements in a comprehensive way. For example, target voltage control has allowed for alumina feeding in some systems. Similarly, anode effects have been used to control the power input. However, the complete range of variable energy requirements are not treated systematically or quantitatively to maintain a constant rate of heat supply available for dissipation through the cell.
SUMMARY OF INVENTION AND OBJECTS
It is an object of the present invention to provide an improved process for controlling aluminium smelting cells in which the heat balance of the cell is comprehensively controlled.
In a first aspect, the invention provides a process for controlling the operation of an aluminium smelting cell, comprising the steps of:
(i) continuously monitoring cell voltage and current,
(ii) calculating the resistance of the cell from the monitored cell voltage and current,
(iii) calculating the rate of change of cell resistance (resistance slope) and providing a smoothed value of said resistance slope,
(iv) utilizing the smoothed resistance slope values to maintain mass balance in the cell,
(v) monitoring cell process operations including alumina additions, electrolyte bath additions, anode changes, tapping, beam raising and anode beam movement,
(vi) delaying the calculation of resistance slope and smoothed resistance slope for a predetermined time when any one of said monitored cell process operations occurs, and
(vii) recalculating said cell resistance slope and smoothed resistance slope after said predetermined time delay so that the smoothed slope is unaffected by process changes with the exception of alumina depletion.
It will be appreciated that the monitored cell process operations cause significant variations in the calculated resistance and the resultant resistance slope such that the latter parameter no longer provides an accurate reflection of the alumina concentration in the cell. By delaying calculation during the process event for a predetermined time sufficient for the resistance value to again become relatively stable, and then recalculating the resistance slope, an `intelligent` smoothed resistance slope can be obtained, and the electrolyte/alumina mass balance may be maintained notwithstanding the effect of the process operation.
The predetermined time delay will vary having regard to the detected operation since different operations have different effects on the stability of the resistance value. In one particular cell (Type VI design), the following delays have been found to be satisfactory after completion of each operation:
______________________________________Operation Delay______________________________________ACD change 60 sec.Alumina feed 60 sec.Anode set 120 sec.Beam raise 120 sec.Bath Addition 300 sec.______________________________________
In a preferred form, the resistance of the cell is calculated using a known formula which compensates for the continuously calculated back EMF of the cell, as will be described further below. The resistance values are filtered using digital filtration techniques (e.g. multiple Kalman filters) in a manner which smooths random and higher frequency pot noise while adequately responding to step changes and the resistance disturbances. This filtered resistance is used for automatic resistance control. The resistance slope is calculated from raw (unfiltered) resistance values as described further below and similar digital filtration is used to continuously calculate smoothed resistance slope values.
The smoothed resistance slope is searched for values exceeding a predetermined slope which is chosen to indicate concentration polarisation and alumina depletion. Different forms of alumina search may be used, and these are described in greater detail in the following specification.
The invention also provides a system for controlling the operation of an aluminium smelting cell comprising suitable means for performing each of the steps defined above.
In a second aspect, the invention further provides a process for controlling the operation of an aluminium smelting cell, comprising the steps of:
(a) monitoring the cell voltage and current and calculating the resistance of the cell from the monitored voltage and current,
(b) monitoring alumina additions to the cell, monitoring other additions to the cell bath and monitoring operational changes including anode movements, tapping, anode setting and beam raising,
(c) continuously calculating the energy absorbed by the process from thermodynamic energy requirements associated with the cell reaction and the events identified in item (b) above,
(d) calculating the heat available for dissipation in the cell from the cell voltage and current and from the continuously calculated process energy requirement determined in item (c) above,
(e) calculating from the calculated heat available for dissipation in (d) and from a selected target power dissipation, the integral of the difference between the heat available and the target power dissipation with respect to time to provide a running heat inventory or integral,
(f) calculating from this heat deficit or surplus in the cell the change in power dissipation required in the cell over a predetermined period to restore heat balance (zero heat integral in item (e)),
(g) establishing an initial target resistance for the cell and an allowable band for said target resistance,
(h) Calculating the required change in target resistance from the required change in cell power dissipation (item (f)) divided by the square of a moving average of the monitored cell current,
(i) altering the target resistance in accordance with the calculated heat inventory (item (e)) and checking that the new target resistance is within said allowable band, and
(j) moving the anodes of the cell to achieve said new target resistance.
Preferably alumina concentration control is carried out by continuously calculating the cell resistance, the rate of change of cell resistance and by smoothing the rate of change values to continuously provide smoothed resistance slope values. Base resistance slope and critical threshold slope for the smoothed resistance slope values indicate target and low alumina concentrations respectively.
The above control process will be seen to take account of both the alumina mass balance of the cell and the short term heat balance of the cell simultaneously.
The calculation of resistance slope and smoothed resistance is preferably delayed for a predetermined time, as described further above, when any one of the monitored cell process operations occur. Thus the resistance slope and smoothed resistance slope are recalculated after the predetermined time delay on the basis of a stabilized series of raw resistance values, so that the smoothed slope is unaffected by process changes, with the exception of alumina depletion.
The target power dissipation is preferably adjusted using bath resistivity data. The bath resistivity and the rate of change of resistivity are calculated and used to adjust the target power dissipation of the cell according to cell response characteristics so that the cell resistivity moves into a target range associated with bath composition and volume.
The cell voltage is preferably monitored to determine the existence of low frequency or high frequency noise in the voltage system.
If the low frequency voltage noise is above a predetermined threshold, the target power dissipation is increased in order to remove cathode sludge deposits. The new target power dissipation value is then used in the control of the cell resistance and hence the heat balance of the cell.
The invention also provides a system for controlling the operation of an aluminium smelting cell comprising suitable means for performing each of the steps defined in the second aspect above.
It will also be noted that if low frequency voltage noise is above a predetermined threshold, the smoothed resistance slope thresholds for low alumina concentration are raised. The critical slope threshold for one pot group under test was 0.025 uΩ/min. at voltage noise levels below the noise threshold of 0.25 uΩ/min. When the low frequency noise exceeds the above threshold, the base slope threshold is ramped by an amount proportional to the amount by which the noise signal exceeds the predetermined threshold. The maximum increment of the ramp is 0.05 uΩ/min. and occurs at a low frequency noise level of 0.50/min. The filtered slope is again compared with the incremented threshold and if it is found to be greater than the threshold, the alumina inventory is then considered to determine whether or not the cell is overfed. If this determination is in the negative, the control system instructs a specific form of alumina feeding cycle to be effected--this is either an end of search or an anode effect prediction feeding cycle.
Long term heat balance is achieved in a further control strategy element which causes adjustment of Q TARGET , based on the data derived from the resistance measurements monitoring the resistivity of the cell in the manner described in greater detail below.
BRIEF DESCRIPTION OF THE DRAWINGS
A presently preferred embodiment of the invention will now be described with reference to the accompanying drawings in which:
FIG. 1 is a diagrammatic representation of the three control functions and their interactions, as performed by a preferred embodiment of the control system according to the invention;
FIG. 2 is a schematic diagram showing the test control system used on an operational pot;
FIG. 3 is a diagrammatic graph showing one form of alumina concentration search (SFS) and anode effect prediction (AEP) performed by the system embodying the invention;
FIG. 4A is an operational graph of resistance values against time showing an alternative method of searching for alumina concentration (namely underfeed/overfeed for point feeders) by the control system embodying the invention;
FIGS. 4B to 4E are schematic graphs showing one example of low frequency noise calculation.
FIGS. 5A and 5B show bath resistivity and rate of change of resistivity ##EQU1## daily mean Q AVAIL and % excess A1F 3 of the bath for two consecutive months.
FIG. 5C shows bath resistivity, Q TARGET and % excess A1F 3 of the bath over a one month period.
FIG. 6 is a diagram showing the calculated energy impact or process energy requirement (and hence compensating action) for feeding a test cell;
FIG. 7 is an operational diagram showing the breakdown of calculated energy absorbed or process energy requirement in a test cell over 24 hours;
FIG. 8 is an operational diagram showing the test cell response under the control system of the invention over 24 hours, and
FIG. 9 shows operational diagrams illustrating the detail of a stop feed search for alumina control of a test cell.
DESCRIPTION OF PREFERRED EMBODIMENT
In the following description, one embodiment of a control system under test on a working cell will be described in some detail. In describing the control system, it will be assumed that the reader is already aware of the operation of an aluminium reduction cell and the standard methods of monitoring cell voltage and current, and the standard methods of calculating the cell resistance. Accordingly these aspects will not be described further in this specification.
Referring firstly to FIG. 1 of the drawings, the control system embodying the invention is shown in simplified flow diagram form. Before proceeding with a detailed description of the control system, a general overview of the system will be provided.
The aim of the control system is to maintain a cell at thermal steady state. That is, the rate of heat dissipation from the cell should be maintained at a constant, target value. For the control system the heat available for dissipation from the cell (Q D , (k W )) may be defined as:
Q.sub.D =(V.sub.C -(R.sub.E ×I/1000))×I-(Q.sub.F +Q.sub.S +Q.sub.A +Q.sub.M) (1)
where,
V C =cell voltage (V)
R E =metered external resistances (eg rods, buswork) (uOhm)
1=line amperage (kamps)
Q F =alumina dissolution power (kW)
Q S =anode setting power (kW)
Q A =power for A1F3/cryolite heating and dissolution (kW)
Q M =remaining process enthalpy requirements (chemical reaction for metal production) (kW)
`V C `, `R E `, and `J` can be measured readily. The various components of the enthalpy of reaction of (Q F +Q S +Q A +Q M ) can also be calculated quantitatively using the thermodynamic cycle for reduction of alumina by carbon [see Grjotheim and Welch, Aluminium Smelter Technology 1988 pp 157-161)], the amperage `I` and a specified current efficiency (CE). Factors such as the carbon ratio and the A1F 3 consumption vary significantly between plants. This will alter the calculations used. The enthalpy components presented in Table 1 were calculated for the applicant's Bell Bay smelter.
TABLE 1__________________________________________________________________________BREAKDOWN OF ENERGY/POWER REQUIREMENTS OF SMELTING PROCESSENERGY ENERGY/POWERCOMPONENT REACTION REQUIRED__________________________________________________________________________Q.sub.F ##STR1## 1820 kJ/kg Al.sub.2 O.sub.3Q.sub.S ##STR2## 1380 kJ/kg carbon (310 MJ/anode)Q.sub.A ##STR3## 1470 kJ/kg AlF.sub.3 1420 kJ/kg cryolite (0.4352 + 0.01138X)l kWQ.sub.M ##STR4##__________________________________________________________________________ N.B. Current Efficiency = x (%), Line Current = 1 (amps), T = 1293K
Note that the CE specific for the control system was made based on tapping history.
The time over which energy is consumed by an individual process event must be defined in addition to the amount of energy consumed. In the control system this was achieved by distributing the total energy requirement of setting, feed or additions over predefined periods. FIG. 6 illustrates the feed energy distribution for a Bell Bay breaker bar cell. Note that the energy balance was integrated over each 10 minute period and converted to power units.
In addition to the calculations in the previous section, other components were required for the application of the control strategy in practice.
Firstly, the dynamics of the reduction cell and control system meant that maintaining an `instantaneous` energy balance was not possible. For example, during cell trials the energy absorbed by a cell was calculated over ten minute intervals and anode beam movements were carried out at five minute intervals. Hence responses to events were delayed by up to 15 minutes. Further the rate and range of target resistance changes were limited, and the line current variation for subsequent ten minute periods did not allow accurate elimination of an energy imbalance. As a result, an integral of the power imbalance was used to modify the target resistance of the cell. That is:
E.sub.i =(Q.sub.Di -Q.sub.T)×0.6+E.sub.i-1 ×c (2)
where,
E i =integral after with 10 minute interval (MJ)
E i-1 =integral after (i-1)th 10 interval (MJ)
c=integral decay factor
Q T =target heat dissipation (kW)
Q Di =heat available for dissipation for ith 10 min. interval (kW)
Cell resistance was increased for E i <0 and reduced for E i >0. Note that a decay factor (`c`) was included in Eqn (2). This was a recognition that when an energy imbalance in a cell persisted, the energy balance was partly self-correcting. (ie A cell loses more heat if it gets hotter.)
A second additional component allowed control of the magnitude of the various discontinuous energy responses. This was necessary in order to model the thermal response of the electrolyte to localised disturbances or material additions. For example, the extra heat needed at an anode after setting is supplied to the bath volume throughout the cell and may have deleterious effects elsewhere. Also the process engineer may wish to reduce the amount of anode beam movement by damping the cell response to individual events. As a result, coefficients (range 0 to 1) were introduced to tune the instantaneous calculations (thus system responses). Energy requirements for feed, setting and additions were divided into instantaneous and background (constant) power inputs. The various background power inputs were calculated from:
(1) Feed--line amperage, CE (monthly average).
(2) Additions--line amperage, CE, addition rate per kg of metal (monthly average).
(3) Anode Setting--anode size, number of anodes, setting `rota`.
The final necessary component of the control system was a feed control technique which permitted regular anode beam movement while monitoring alumina concentration--thereby allowing the cell energy balance to be always under control. Search techniques were developed with these functions, where the target alumina concentration was detected via a continuously calculated slope of resistance. No scheduled anode effects (AEs) were included in the feed control strategy. The associated large, uncontrolled energy inputs to the process would have been in conflict with the control philosophy, and are difficult to compensate for in the thermal balance.
Referring again to FIG. 1 of the drawings, the control system has three basic strings, the first two affecting the short term heat and mass balance of the cell, and the third affecting the medium to long term heat balance of the cell. The control system is implemented using a computer for monitoring the functions of the cell or pot (pot computer), such as a Micromac 6000 computer suitable for the aluminium industry, and a supervisory computer for receiving data from each of a number of pot computers and for instructing the pot computers to perform various functions.
Initial input data to the computers includes target heat dissipation Q T , the specific current efficiency CE for the cell being controlled, the bath resistivity target range for the cell, thermodynamics data, as described in greater detail above, relating to the cell and a `typical` back emf (EMF) of the cell calculated by regression in a known manner.
The essential operating parameters of the cell are dynamically monitored, and these parameters include: the voltage of the cell V, the current of the cell I, alumina additions, cell bath additions, operations such as anode setting, beam raising, manual alumina addition and oreing up, and anode to cathode distance (ACD) movements. From these dynamic inputs, the resistance (R) of the cell is continually calculated from (V-EMF)/I, and the cell resistivity ρ is calculated from (δ R/δ ACD)A, where A is the estimated area of the anodes in the cell.
CONTROL STRING 1: ALUMINA FEED CONTROL
In the first control string, the pot computer calculates the level of noise in the voltage signal, 0 to 0.1 Hz indicating low frequency noise and 0.1 to 1 Hz indicating higher frequency noise, and further calculates the filtered rate of change of resistance with time (smoothed resistance slope) every second. The basic steps in the filtered slope calculation for each time cycle are:
(i) Raw Resistance Slope Calculation.
Raw slope is calculated from the following equation:
S.sub.0 =(R.sub.0 -R.sub.1)/(Δt(1+1/γ)) EQ (3)
where
S 0 =raw slope at (t+Δt)
R 0 =raw resistance at time (t+Δt)
R 1 =single stage filtered resistance at time t
Δt=time interval of resistance polling
γ=filter constant for filtered resistance (R 1 ).
It should be noted that the denominator in EQ (3) above represents the mean age of the filtered resistance (R 1 ).
(ii) Box filter for out of range raw slopes:
The raw slope is checked to determine if it is within the present box filter limits. If this test fails, no further calculations are made in this cycle--the slope value is assumed not to be associated with changes in alumina concentration. In the case of the pot under test, the box filter limits were -2.0 and 2.0 micro-ohms/minute.
(iii) Filtered resistance is recalculated (for use in the next time cycle).
R.sub.1 =R.sub.1 (1-γ.sub.1)+γ.sub.1 R.sub.0 EQ 4
(iv) A three-stage filter is used to find the filtered resistance slope (called smoothslope). For the ith stage:
S.sub.i =S.sub.i (1-γ.sub.i)+γ.sub.i S.sub.i-1 EQ 5
where γ i is the pre-set filter constant of the ith stage. In the case of one pot under test, typical filtration constants are 0.100, 0.050 and 0.095 for γ 1 , γ 2 and γ 3 respectively.
The above operations adequately filter high frequency noise from the resistance signal to produce a realistic filtered slope (with some lag from the three stage filter). In addition, a delay mechanism (discussed above) is included in the calculations to remove the effects of pot operations on the slope, including:
(i) break and feed (normal cycles, AEP*)
(ii) anode movement
(iii) bath additions
(iv) tapping*
(v) anode setting*
(vi) beam raising*
Slope calculations are stopped during these operations, and for a pre-set period afterwards. Near the end of these delay periods, the first stage filtered resistance (R 1 ) is re-set to the mean of a specified number of raw resistance values. For the cases marked *, S 1 to S 3 are also zeroed. In the case of the pot under test, the respective delays following each of the above operations are:
i) 60 seconds
ii) 120 seconds
iii) 300 seconds
iv) 10 minutes
v) 120 seconds
vi) 120 seconds
Delay periods associated with other operations include: When the pot is put on "manual" for any reason, a delay of 30 seconds is introduced.
When alumina is manually added, a delay of 120 seconds is introduced.
Similarly when oreing-up is performed, a delay of 60 seconds is introduced.
A pre-set delay is also implemented when step ii) of the slope calculation fails to give in-range slopes on a given number of consecutive tests. This is intended to trap the gross resistance disturbances not initiated/expected by the pot computer (e.g. sludging may cause an unpredictable resistance response).
Different cells will require different delays depending on their operational characteristics and specific bath volumes, and the delay involved for each operation will be empirically determined by a skilled operator for input into the pot computer.
Two alumina search techniques are available on the system, stop feed search (SFS) and feed search (FDS). Both techniques terminate search on a threshold value of increasing resistance slope, implying low end point alumina concentrations and both techniques allow heat balance regulation (anode movement) during the search. The special features of each are described below.
i) SES
This technique is essentially a stop feed during which the filtered resistance slope is checked every second for values above the critical slope (critslope) indicating alumina depletion. Once the critical slope is attained on a sufficient number of consecutive readings, search is terminated by initiation of an end of search feed followed by the resumption of the previously nominated cycle (see FIG. 3).
The search can also be terminated (classed an unsuccessful search) under the following circumstances:
Cancelled due to time limitation (max search time).
Cancelled due to anode setting, tapping, oreing-up, bath additions.
Cancelled if cell is switched to MANUAL.
The unique features of the SFS with respect to the present invention are:
1. the ability to monitor and interpret the resistance slope through all phases of the search.
2. the ability to move the anodes freely through all phases of the search.
3. the crit slope in the search is a function of the voltage noise in the cell.
The SFS technique has been applied to both breaker bar and point feed cells.
ii) FDS
This is a more complex search procedure but one which has the potential for fine alumina concentration control on point feed cells. The strategy involves following resistance slope before and during underfeeding and overfeeding periods until a target alumina concentration is achieved.
The stages of the searching routine are as follows:
(a) After commencement of searching, the filtered resistance slope is monitored for a short time period and compared with a parameter, base search slope, near the minimum point on the resistance-time curve in FIG. 4A. The objective is to adjust alumina concentration to this base level.
(b) As the alumina concentration of the cell decreases, the resistance slope increases from a negative value up to the value of the base search slope. Thus slopes more negative than base search slope indicate a higher than `base-level` alumina concentration and are actioned by changing to x% underfeed. Slopes more positive than base search slope indicate a lower than base-level concentration and cause a y% overfeed cycle to begin.
(c) When the filtered slope passes through base search slope (or the under/overfeeding period times out--whichever is first), a feedrate of x% underfeed is selected for the remainder of the search period.
(d) The filtered slope is then monitored until its value increases positively to target search slope. At this stage the alumina concentration has been adjusted to its target operating level. FDS is terminated and the previously selected (nominal or fixed) feedrate is resumed immediately.
By gradually increasing base search slope towards the target value (target search slope), it is possible to minimize the absolute variation in alumina concentration during FDS under point feeding of alumina. Additionally, if the percent under and overfeed are decreased to small values (such as 10%), the proportion of time spent on search will increase--allowing very close feed control for most of the operation.
ANODE EFFECT PREVENTION MECHANISM
Anode effect prediction (AEP) is provided by a check on the filtered resistance slope every second during normal feeding of the cell (FIG. 3). If it exceeds a pre-set AEP slope an AEP feed cycle is initiated immediately to avoid an anode effect.
This high resistance slope results from the critical depletion of alumina concentration in the cell during periods when alumina searching is not occurring. Resistance changes due to operations like setting, tapping and bath additions are removed by the filtered slope calculation. However, resistance changes due to metal pad instability are included in the filtered slope. Hence the pre-set AEP slope is increased if excessive low frequency noise is detected, as discussed further below, to reduce the likelihood that the system will trigger an AEP feeding cycle due to low frequency noise. It will be appreciated that low frequency, cyclic voltage variations (of less than one cycle per second) are sometimes observed due to instability in the liquid aluminium pad. The rates of resistance increase associated with these cycles can, in the case of severe instability, exceed the resistance slope thresholds above, triggering alumina feeding when this is not warranted. To guard against this occurrence the slope thresholds for both end of search and AEP are increased by a predetermined amount when low frequency voltage noise is detected above a certain amplitude (in micro-ohms). The critical slope threshold for one pot under test was 0.035 uΩ/min. and the voltage noise threshold was 0.25 uΩ/min. When the low frequency noise exceeds the above threshold, the critical slope threshold is ramped by an amount proportional to the amount by which the noise signal exceeds the predetermined threshold. The maximum increment of the ramp is 0.05 uΩ/min. and occurs at a low frequency noise level of 0.50 uΩ/min. The filtered slope is again compared with the threshold and if it is found to be greater than the threshold, the alumina inventory is then considered to determine whether or not the cell is overfed. If this determination is in the negative, the control system instructs an AEP alumina feeding cycle to be effected. The operation of AEP can also be stopped for a defined period after an AEP prediction as further protection against excessive AEP triggered feeds during periods of cell instability.
Both high and low frequency noise calculations are performed continuously in this module. While the high frequency calculation is a simple 1 Hz, minimum R/maximum R relationship, the low frequency characteristic needs further explanation and this is given below.
LOW FREQUENCY NOISE CALCULATION
The main function of the low-frequency noise calculation is to detect noise generated by metal pad instability. In this novel formulation, a group of consecutive resistances are summed, then averaged. A ring buffer containing a time sequence of these averages are then stored for some period of time (usually less than 2 AVC periods). FIG. 4B is an example of the resulting data in a computer; essentially it is a resistance vs time plot with the high-frequency noise removed. The low frequency noise is the sum of absolute differences in adjacent resistance averages minus the absolute difference between the newest and oldest averages, divided by the time interval. ##EQU2## where AR i is the average resistance at time t i Examples of idealized curves and their noise are shown in FIGS. 4C to E.
The calculation of noise with the addition of each new mean resistance (and the elimination of the oldest resistance) requires less calculation time than standard noise calculations. In the case of one test pot trial the mean resistances are calculated over 10 seconds, and 30 values (5 minutes history) are stored.
CONTROL STRING 2: SHORT RANGE HEAT BALANCE CONTROL
In the second control string the heat supplied and the heat required for aluminium production are calculated from the dynamic inputs described above (cell voltage and current, alumina additions, bath chemistry additions, operations and anode movements) and the heat available (Q AVAIL ) for dissipation by the cell is also calculated. The difference between available heat and the previously determined target heat (Q T ) is integrated with respect to time and from this integral a running heat inventory is calculated. The target resistance (R TARGET ), derived in the manner described above from Q TARGET , is regularly updated on the pot computer to adjust the heat balance of the cell to minimize the imbalance represented by the heat inventory integral. The target resistance must lie between the specified minimum and maximum allowable limits. These limits are, for example, 32-40 uΩ, for a typical pot under test, i.e. a band of about 6 to 8 uΩ. If the average actual resistance over the resistance regulation (AVC) period is significantly different (outside a specified dead band) from the new target resistance, the pot computer then issues a beam raise or lower signal to move the cell resistance back into the dead band. This instruction is limited to a pre-set amount (ΔR max.).
If the updated resistance target consistently falls above or below one of the allowable limits, disallowing the regulation of resistance as described above, the operating amperage, ore cover level, or bath and metal levels are reviewed so that a more flexible region of the operating envelope can be chosen for the cell.
The set point, R TARGET , is updated at regular intervals on the basis of short range heat balance calculations. The short range calculations require the following information:
Real time clock--for scheduling and distributing intermittent power absorbed functions during operations.
V i , I i , R i --one minute average voltage, current and resistance.
P CELL --Cell Power input (heat balance interval average).
Current efficiency--based on cumulative metal tap.
Software switches--indicating commencement of a cell operation.
Alumina dump counters--metering alumina actually fed to the cell.
P ABSORB --power absorbed calculation This information is used to calculate three parameters:
Q AVAIL --The available power dissipation over the previous period.
R--The average actual cell resistance over the previous period.
I--The average cell amperage over a longer time period (default period is one hour).
The calculated value of the available power dissipation is compared to the target value for the cell and the thermal imbalance ΔQ obtained. (The target value (Q TARGET ) is initially determined from a steady-state computer thermal model prediction and cell operating diagram and then updated imbalance is integrated and converted directly into a ΔR and an R TARGET using the average value of amperage and the previous target resistance respectively.
As mentioned earlier, resistance regulation maintains cell resistance at or near the target value calculated in the heat balance program. Also, as will be discussed, anode movements do not in any way affect the mechanics of feed control on the cell. Functionally, the implications of these strategy requirements are as follows:
i) resistance regulations is prohibited on three occasions only:
during beam raising
during anode setting
during tapping when TVC is operative.
ii) resistance regulation frequency is increased so that the interval between resistance regulation is reduced to five minutes or less.
iii) The proportionally constants for resistance regulation buzz time (decisec/micro-ohm) are set as close as possible to the reciprocal product of resistance/cm of ACD and beam speed (up or down). This ensures that one resistance regulation attempt moves the resistance to its target value--climinating kilowatt errors from this source.
iv) The dead band for resistance regulation is tight (±0.20 micro-ohm).
CONTROL STRING 3: MEDIUM-LONG RANGE HEAT BALANCE CONTROL
In the final control string, long term heat balance control is used to continually update the target power dissipation Q TARGET through trends in bath resistivity data. This prevents longer term changes in bath thermal conditions and chemistry which occur through breakdown of ore cover, changes in current efficiency or amperage, and variations in anode carbon quality with respect to reactivity, thermal conductivity and anode spike formation.
Bath resistivity data is used to detect all chemistry and thermal conditions in real time.
Bath resistivity is calculated at approximately hourly intervals, using controlled beam movements, with beam movement measured in the usual manner by a shaft counter.
Using the average change in cell resistance before and after the beam movement sequence, bath resistivity is calculated from the known relationship. ##EQU3##
ΣR FIXED is the sum of the contribution of resistance values due to ohmic effects and possible reaction decomposition effects. This value is assumed to be constant for changes in ACD.
A A is the nominal area of the anode and is assumed to be constant
δACD is measured using the shaft counter
δΔR is the difference between cell resistance before and after the 20 decisecond buss-up.
The bath resistivity and its rate of change is a good indication of the concentration of A1F 3 . There is a lag time between a rise in % XS A1F 3 and a rise in bath resistivity. This characteristic depends on liquid bath volume, anode and cathode condition, and other pot characteristics. Freezing in a cell occurs when the bath super-->heat drops below a certain level and is identifiable by an increase in % XS A1F 3 . After taking the lag time into consideration, if the bath resistivity is increasing to a level where electrolyte freezing and increases in % XS A1f 3 are occurring, the Q TARGET is adjusted in the system so that more power is supplied to the cell. This causes a greater rate of heat dissipation through the electrolyte and increases its superheat, reducing its tendency to freeze. The response must be tuned to the lag time of the resistivity measurement as well as to the Q DISS /Superheat relationship, so that Q TARGET does not overshoot its correct value.
The initial or starting value for the target heat dissipation Q T is derived as follows.
Thermal model calculations (Finite element prediction of isotherms and flows within the cell in question) are used to determine the steady-state level of heat loss required from a particular cell design (e.g. the test pot referred to above is a Type VI cell design and requires 220-230 kW depending on metal level and alumina cover). This target or `design heat loss` is Q CELL .
The process energy requirement for aluminium production can be calculated in a known manner for the cell once the line amperage is known: ##EQU4##
In Table 1 this is calculated to be 1.956 Volts×1 at 95% current efficiency (CE) for a typical test cell at Bell Bay (At 90% efficiency this figure is 1.841 Volts×1).
Adding to this the power loss from the bus bar around the cell:
R.sub.EXTERNAL ×I.sup.2
we have the total power input required for the cell:
TABLE 1______________________________________At I = 87 kA; P.sub.TOTAL = 170.2 kW + 225 kW + 18.2 kWand 95% CE = 413.4 kW R.sub.EXT = 2.4on Pot under test Q.sub.CELL = 225 kW V.sub.ABSORB = 1.956 VP.sub.TOTAL = P.sub.ABSORB + Q.sub.CELL + P.sub.EXTERNAL = V.sub.ABSORB .I + Q.sub.CELL + R.sub.EXTERNAL.I.sup.2______________________________________
This power input equates to a cell voltage of ##EQU5## This cell voltage equates to a target (initial) cell resistance of ##EQU6## Typically this resistance will be used as a back-up or start-up value on the pot computer. It will also lie in the mid-range of the allowable target resistance band. Initial Settings are therefore:
Q.sub.TARGET =225 kW
R.sub.TARGET =35.65 uΩ
However R TARGET will change every ten minutes by R as the P ABSORB term is continuously recalculated according to pot requirements (feeding, anode setting etc.).
FIGS. 5A and 5B show selected pot parameters over 2 months operation of a reduction cell, with constant Q TARGET . The % XS A1F 3 varied significantly over this period and ρ and ##EQU7## are seen to be good indicators of this. Twice during the period shown, manual increases to the power input were made to increase the cell superheat and reduce the % XS A1F 3 (times `B` and `C`). In both cases high values of ρ and ##EQU8## were evident before manual intervention.
Such observations resulted in the development and testing of a closed-loop control system in which the target energy input to the cell (Q TARGET ) was changed based on ρ and/or ##EQU9## For the 1 month period in FIG. 5C control of Q TARGET was based on ρ only. (Both the manually set `nominal` Q TARGET and `actual` Q TARGET are shown in this Figure.) Note that the high % XS A1F 3 on days 4, 11, 19 and 29 correspond with high ρ values. The resultant increased power inputs controlled the high % XS A1F 3 excursions, making manual intervention unnecessary.
SYSTEM TESTING
Frequent V AVC action maintains the actual resistance close to the continually updated target value, and the magnitude of its allowable resistance changes are specified as a heat balance parameter--within absolute resistance limits as discussed earlier. More importantly, AVC will not be disallowed during operations unless it is physically unreasonable to perform beam movement. These occasions are during tapping, anode setting and beam raising.
An extended trial of the above described control system has been made on a group of cells at one of the applicant's smelters. For the trial the CE and `Q T ` for each cell were selected based on long-term data computer modelling and cell condition. It should be noted that cell condition fluctuates due to factors such as cell ore cover, seasonal temperatures, alumina properties, bath composition and cell age. Hence the parameters should be updated on a regular basis.
Calculation of the power absorbed for the control system used the following hardware inputs:
voltage and amperage (1 Hz)
a switch to indicate anode setting (at cell)
keyboard input for bath additions in kg (adjacent to cell)
keyboard input for manual alumina addition and oreing-up
The results presented in FIGS. 7 and 8 show the behaviour of a cell under the control system over 24 hours.
FIG. 7 shows the calculated heat absorbed by the cell, broken down into it's four operational components. Fluctuations in the power required for reaction (metal production) (FIG. 7a) were due to line amperage variations. The power absorbed by alumina feeding (FIG. 7b) had a strong cyclic pattern. This pattern is accentuated because the alumina searches (SFS) included cessation of feeding (for the day shown). FIG. 7c shows the effect of replacing two anodes. For setting, the energy distribution was spread over 5 hours; this was based on trial data and computer modelling of the heat absorbed by the new blocks. FIG. 7d includes the energy input for a 15 kg bag of A1F3. Note that 50% of feed power, 50% of setting power, and 20% of the additions power were supplied as constant background inputs, while the remainder in each case was triggered by the respective events.
The calculation of the total absorbed energy is shown in FIG. 8a. FIG. 8b shows the power available for dissipation from the cell as heat (Eqn 1). Note the target dissipation rate of 240 kW for this cell. The target and calculated actual heat dissipation clearly show the heat deficit/excess in FIG. 8c. The cell had an energy imbalance for periods up to 2 hours. This was primarily due to the power input constraints imposed by the cell resistance control band. FIG. 8d shows the control band of 32.5 to 38 uOhm used over the 24 hour period. Anode beam movements are clearly larger, and more frequent, than for control systems previously reported in the literature. This reflects the extent of thermal disturbance which is imposed on most reduction cells in a single day.
FIG. 9 illustrates the behaviour of the alumina feed control component of the system during a typical, successful stop feed search (SFS). (The search period is marked in FIG. 8d.) One minute averages of anode cathode distance (ACD), cell resistance and slope of resistance are shown. The centre channel bath temperature, measured at ten minute intervals, is also presented. The change in ACD was transduced using the rotation shaft counter (proximity switches) on the anode beam drive shaft. The resistance slope (FIG. 9d) was zeroed at the start and end of the SFS; the end of search slope was 0.025 uOhm/min. The search lasted approximately 90 minutes, and there was substantial beam movement throughout. The high resistance/ACD at the start of searching was due to the energy requirement of a 23 kg alumina feed immediately beforehand. Once this energy was supplied, the control system reduced the power input. The control approach allowed long SFSs to be scheduled without the bath temperature or superheat increasing substantially. This allowed back-feeding and depletion of alumina to the target level. The stable bath temperature is clearly shown in FIG. 9c, although there was a temperature fall caused by the feed before SFS. Typically, a bath temperature change of only +/-4 C was measured during SFS. While there is some fluctuation in the dynamics of the resistance slope, the underlying trend and threshold values were reliable. The SFS technique achieved good feed control, consistently, with [0.3 AEs/day.
The trial results demonstrate a number of inherent advantages in the control system. Since the energy requirements were calculated from basic information (e.g. line amperage, alumina dumps, thermodynamic data), changes to the operating environment were catered for automatically. If a variation in potline amperage occurred, the control system automatically adjusted the resistance targets of the cell. The mean resistance at which the cell operated over longer periods were also varied if the long-term amperage was changed. Similarly, any decision to change the number of dumps for each feed, the timing of SFSs or the number/size of anodes set was catered for easily. Fundamentally, this was due to the control system being based on the real operating target and component energy requirements of the smelting process rather than the loss direct measures of target voltage or resistance. This same mechanistic approach can also reinforce the understanding of the process for those operating it.
There are, of course, some practical constraints imposed on the control system by the process. If the potline amperage is reduced significantly for a sufficient period, each cell will experience a substantial energy deficit. Thus all cells in the potline will attempt to operate at their maximum target resistance simultaneously. The potline voltage may then exceed the rectifier limits. This problem can be overcome by including safety factors in the control system which limit the closure of energy balance attempted under extreme potline conditions. On an individual pot basis there may also be variations in heat dissipation, current efficiency and the integrity of the top cover/crust, requiring individualization of the Q T targets for each cell.
The control system embodying the invention maintains a target rate of heat loss from a reduction cell via calculation of the energy absorbed by the process. The trial results show that the system made regular anode beam movements while maintaining good thermal balance on the cell. The control system described here is a building block for the optimization of reduction cell efficiency via understanding and reducing variations in the cell thermal balance.
The overall configuration of a typical control system is shown in FIG. 2. The physical location of each control module on the system in this implementation has been determined by the computing power available at the pot computer and supervisory computer levels respectively. Thus the more complex heat balance control module has been placed on a Microvax supervisory computer. This also has the advantage of providing an interactive human interface to the control function for diagnostics and further development. As a general strategy, however, all essential control functions in a distributed potline system should be located at the lowest intelligent level--the pot computer in this case--so that maximum safety and redundancy can be built into the system.
The computer control functions detailed in FIG. 2 will be recognised by persons of skill in the art and since many of the functions are not critical to the invention, they will not be further described in this specification. | A process for controlling an aluminum smelting cell comprising monitoring the cell voltage and current, alumina dumps, additions, operations and anode to cathode distance movements, continuously calculating the cell resistance and the bath resistivity from said monitored cell voltage and current, monitoring the existence of low frequency and high frequency noise in the voltage of the cell, continuously calculating the time rate of change of resistance of the cell, suspending calculation for a predetermined time when an alumina dump, addition, operation or ACD movement occurs, establishing filtered resistance slope thresholds, determining whether the low frequency noise is above a predetermined threshold, and if so, increasing the filtered slope thresholds for low alumina concentration detection, calculating an alumina inventory from the alumina dumps, determining whether the cell is overfed, and if not feeding alumina to prevent an anode affect, calculating the heat supplied and heat required for aluminum production, calculating the heat available for dissipation, calculating the target heat for the cell, calculating the difference between the available heat and the target heat with respect to time, calculating a running heat inventory from the integral of this difference, establishing a target resistance for the cell and modifying that target resistance to achieve a zero heat integral, checking that the target resistance is an allowable value, and moving the anodes of the cell to establish the new target resistance, estimating the time rate of change of bath resistivity and checking whether resistivity and the derivative are greater than predetermined limits, and if so, adjusting the target heat of the cell to maintain the long term heat balance of the cell. | 2 |
CROSS REFERENCE TO RELATED APPLICATION
This application claims priority from German Patent Application No. 103 05 048.5, which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
The invention relates to a device on a carding machine for setting the working gap between the cylinder and at least one neighbouring roller, which cooperate with one another with a small gap between their cylindrical surfaces (working gap) at the fibre transfer points.
The working gap may be readjustable to a pre-determined value as a result of changes in dimensions caused by thermal expansion and/or centrifugal forces. In carding, increasingly large amounts of fibre material are processed per unit of time, which requires higher working component speeds and higher performance. The increasing throughput of fibre material (production rate), even when the working surface area remains constant, results in increased generation of heat as a result of the mechanical work. At the same time, however, the technological carding result (sliver uniformity, degree of cleaning, nep reduction etc.) is constantly being improved, which requires a greater number of effective surfaces in carding engagement and narrower settings of those effective surfaces, e.g. fixed card tops and/or revolving card tops, with respect to the cylinder (tambour). The proportion of synthetic fibres being processed, which—compared with cotton—generate more heat as a result of friction when in contact with the effective surfaces (clothings) of the machine, is continually increasing. The working components of high performance carding machines are nowadays totally enclosed on all sides in order to conform to the high safety standards, to prevent the emission of particles into the spinning room environment and to minimise the need for servicing of the machines. Grids or even open, material-guiding surfaces allowing exchange of air are largely a thing of the past. The said circumstances markedly increase the input of heat into the machine, while the discharge of heat by means of convection is markedly reduced. The resulting more intense heating of high performance carding machines leads to greater thermo-elastic deformation which, on account of the non-uniform distribution of the temperature field, affects the set spacings of the effective surfaces: the gaps between cylinder and card top, doffer, fixed card tops and separation points are reduced. In an extreme case, the set gap between the effective surfaces can be completely consumed by thermal expansion, so that components moving relative to one another collide, resulting in considerable damage to the affected high performance carding machine. Accordingly, particularly the generation of heat in the working region of the carding machine can lead to different degrees of thermal expansion when the temperature differences between the components are too great.
Carding gaps and roller spacings on a carding machine are extraordinarily important. The carding quality stands or falls with the exact setting of those gaps (roller gaps). Under the action of heat, the rollers expand and the gaps change. In addition to expansion of the rollers caused by centrifugal force, which greatly changes the gaps, a high production rate and carding-intensive synthetic fibres additionally give rise to intense heating of the rollers. Thermally induced changes in the dimensions of the rollers occur. In order to achieve optimum carding quality it is necessary for the roller spacings to remain constant during operation. “Constant” means in this context that the change in spacing should be preferably less than 0.01 mm.
In a known device (DE 29 48 825), in a carding machine having at least two cooperating rollers the gap between the two rollers is changed in order to compensate for heating. This change is effected by means of additional mechanical displacement elements which are so constructed that they are able to change the spacing of the axes of the rollers in accordance with the prevailing temperature. For that purpose, the stationary framework of the carding machine is in the form of a frame having four supports (only two are shown) and having two horizontal longitudinal bars (only one is shown). The two longitudinal bars and the supports are joined together by crossbars (not shown) to form a stable, rigid support frame for two rotating rollers (cylinder and doffer) which are equipped with pointed clothing and operate a short distance a apart. The cylinder is fixedly mounted so as to be rotatable about its axis by means of two bearings (of which only one is shown) which are tightly screwed to the longitudinal bars by means of screws, and is driven and rotated. The doffer is likewise mounted so as to be rotatable about its axis by means of two bearings (only one is shown) on the longitudinal bars of the framework. The bearings for the doffer are not, however, tightly screwed to longitudinal bars but are each guided by means of two collar screws so that they are displaceable parallel to the axis by a small amount of the order of 1 to 2 mm. For that purpose, slot openings are provided in the bearings for the projecting screws, which allow exact lateral guidance of the bearings while ensuring their displaceability in the longitudinal direction. By parallel displacement of the bearings in the slot openings, the gap between the cylindrical surfaces of the two rollers can be varied. For that purpose, the machinery framework is provided on each of its longitudinal bars with a fixed stop for adjusting devices (displacement elements) which are inserted between the fixed stop and the bearing of the doffer. The adjusting devices are capable of determining the position of their corresponding bearing in respect of that of the fixed bearing for the cylinder. A disadvantage of this device is the structural complexity. Additional separate mechanical adjusting elements are required for displacement. A particular shortcoming is that the bearings of the high-speed doffer are displaceably arranged. In addition to the apparatus-related expense for the displacement elements on the bearings, the fact that the bearing arrangement for the heavy doffer roller is not completely rigid is a particular disadvantage. Displacement of the doffer that is only very slightly unequal results in a non-uniform roller gap and can lead to the destruction of the machine. In the known device, in every case the bearings of the doffer have to be loosened for adjustment and then fixed again.
It is an aim of the invention to provide a device of the kind described at the beginning which avoids or mitigates the mentioned disadvantages, which has an especially simple structure and enables a predetermined spacing between neighbouring rollers to be set in a simple manner in the event of changes in the dimensions of the rollers.
SUMMARY OF THE INVENTION
The invention provides a carding machine having a carding cylinder and at least a first cooperating device in cooperating relationship with the carding cylinder, comprising an adjusting device for setting a working gap between the carding cylinder and said first cooperating device, the adjusting device comprising a thermal device for adjusting the temperature of a support member of the cylinder.
As a result of the features according to the invention it is possible in a simple manner to maintain constant roller spacings in carding machines under the action of heat. The machinery framework can be partitioned thermally in such a manner that the cylinder is raised by heating of its supports, which are “insulated” from the remainder of the framework. On so doing, the gap between the cylinder and at least one neighbouring roller, for example licker-in and/or doffer, is changed. In this way, compensation of the roller diameter changed by the change in temperature can be realised in a specific manner and with a low heat output. Special further advantages are that separate adjusting elements for the displacement of a roller and the mechanical and fibre-technological problems associated with roller displacement are substantially or completely avoided. The roller gap can be made to track a change in temperature automatically, without the need to loosen, displace and then fix a bearing for a roller on the framework. The bearings of the rollers can remain rigidly connected to the framework.
The first cooperating device may be a clothed roller, for example, a doffer. The machine may comprise a second cooperating device, for example, a licker-in. Advantageously, the thermal device is so arranged that the temperature of the support member can be so matched to the working gap that, in the event of a change in the dimensions of the cylinder the working gap can be set or readjusted.
Advantageously, a framework wall is provided with means for heating at least one element of the framework wall. The framework wall may have a heating element. The heating element may be integrated into the framework wall.
The framework wall may have at least two support struts on each side. The support struts may have a crossmember. The framework walls may be expandable. The support struts may be expandable or contractable in the vertical direction. The cylinder and at least one neighbouring roller may be arranged on their own framework walls or struts. The framework of the cylinder is advantageously higher than the framework of at least one neighbouring roller. The heating element is then advantageously arranged in the region of the cylinder framework that projects above the frameworks of a neighbouring roller. The separate neighbouring frameworks may be connected to one another, for example by welding.
Advantageously, the temperature to be set is determined in accordance with the relationship: Δa=R×α×ΔT. Advantageously, the spacings of the rollers are settable by an electronic control and regulating device. The electronic control and regulating device may have a memory for desired values for the roller gaps (working gaps). The predetermined roller gaps may be constant. The cylinder may be associated with at least one temperature-measuring element. The doffer may be associated with at least one temperature-measuring element. At least one licker-in may be associated with at least one temperature-measuring element. The temperature-measuring elements may be associated with the surfaces of the rollers. The temperature-measuring elements may be connected to the electronic control and regulating device. The temperature-measuring element may be in the form of a temperature sensor for the temperature of the roller surface. There may be a gap-measuring element for the gap between two neighbouring rollers. The gap-measuring element may be connected to the electronic control and regulating device. The gap-measuring element may be an inductive sensor. The gap-measuring element may be an optical sensor, for example a laser sensor. The gap-measuring element may be able to measure the working gap between two neighbouring rollers. The heating element may be connected to the electronic control and regulating device. There may be at least one heating element on each side of the carding machine. The temperature of the heating elements may be adjustable. The temperature adjustment may be effected stepwise. The temperature adjustment may be effected steplessly.
The invention further provides a device on a carding machine for setting the working gap between the cylinder and at least one neighbouring roller, which cooperate with one another with a small gap between their cylindrical surfaces (working gap) at the fibre transfer points and in which the working gap is readjustable to a pre-determined value as a result of changes in dimensions caused by thermal expansion and/or centrifugal forces, characterised in that the temperature of the framework walls carrying the cylinder can be so matched to the working gap by means of devices for supplying or discharging heat that in the event of a change in the dimensions of the rollers the working gap between the cylinder and at least one neighbouring roller can be set or readjusted.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatic side view of a carding machine for the device according to the invention;
FIG. 2 shows, in diagrammatic form, a section through the cylinder with shaft, framework walls with heating elements and side panels;
FIG. 3 shows the spacings of the clothed cylinder from a licker-in and from the doffer;
FIG. 4 is a side view of a carding machine framework wall with three framework part-walls for the cylinder, for a licker-in and for the doffer;
FIG. 5 a is a side view of a carding machine with starting working gaps between the cylinder and a licker-in and the doffer;
FIG. 5 b is a side view of the carding machine of FIG. 5 a showing changed working gaps; and
FIG. 6 is a block diagram showing the setting and readjustment of the working gaps between neighbouring rollers.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a carding machine, for example a high performance carding machine DK 903 made by Trützschler GmbH & Co KG of Mönchengladbach, Germany, having a feed roller 1 , feed table 2 , lickers-in 3 1 , 3 2 , 3 3 , cylinder 4 , doffer 5 , stripper roller 6 , nip rollers 7 , 8 , web guide element 9 , sliver funnel 10 , delivery rollers 11 , 12 , revolving card top 13 with card top bars 14 , can 15 and coiler 16 . The directions of rotation of the rollers are indicated by curved arrows. M denotes the centre point (of the axis or shaft) of the cylinder 4 . Between licker-in 3 and card top guide roller 3 a there are working elements, for example fixed carding segments 17 , and between doffer 5 and card top guide roller 13 b there are working elements, for example fixed carding elements 18 . Reference numeral 19 denotes the cylinder covering (cylinder cover elements);. reference numeral 20 denotes the licker-in covering (cover elements) and reference numeral 21 denotes the doffer covering (cover elements). The cylinder 4 is provided with clothing 4 a ; the licker-in 3 3 is provided with clothing 3 a and the doffer 5 is provided with clothing 5 a . Reference letter A denotes the working direction. The carding machine is fully enclosed by a machinery housing 34 , especially made of sheet metal with doors, flaps and the like.
FIG. 2 shows a portion of the cylinder 4 having a casing 4 e , with a cylindrical surface 4 f , and cylinder bases 4 c , 4 d (radial support elements). The surface 4 f is provided with clothing 4 a , which in this example is in the form of wire having sawteeth. The sawtooth wire is wound on the cylinder 4 , that is to say is wound around it in closely adjacent turns between side flanges (not shown) in order to form a cylindrical working surface equipped with points. On the working surface, fibres should be processed as uniformly as possible. The carding work is performed between the opposing clothings. It is influenced essentially by the position of the one clothing relative to the other and by the clothing gap a between the tips of the teeth of the two clothings. The reference letter a is used herein to refer to both the gap between the cylinder clothing tips and the card top clothing tips and the gap between the clothing tips of licker-in 3 3 and the cylinder clothing tips, but that is not to be taken as implying that those gaps are equal. The working width of the cylinder 4 is a determining factor for all other working elements of the carding machine, especially for the revolving card top 14 or fixed card tops (a revolving top 14 is shown in the drawings) which, together with the cylinder 4 , card the fibres uniformly over the entire working width. In order that uniform carding work can be performed over the entire working width, the settings of the working elements (including additional elements) must be adhered to over that working width. The cylinder 4 itself can, however, be deformed by the winding-on of the clothing wire, by centrifugal force or by heating arising as a result of the carding process. The shaft 22 of the cylinder 4 is rotatably mounted in bearings 26 a , 26 b (see FIG. 5 a , 5 b in which only bearing 26 a can be seen) which are mounted on the fixed machinery framework 23 a , 23 b . The diameter, for example 1250 mm, of the cylindrical surface 4 f , that is to say twice the radius r 3 , is an important dimension of the machine and is increased by the working heat during operation. The side panels 24 a , 24 b are mounted on the two machinery frameworks 23 a , 23 b , respectively. The two flexible bends 25 a , 25 b are mounted on the side panels 24 a , 24 b , respectively. Heating devices 29 a , 29 b are provided, respectively, in machinery frameworks 23 a , 23 b.
The rollers shown in FIG. 3 arranged immediately adjacent to the cylinder 4 and cooperating therewith, the licker-in 3 3 and the doffer 5 , are constructed and clothed in substantially the same way as the cylinder 4 , so that the comments made above in connection with the cylinder 4 in the description of FIG. 2 apply in corresponding manner. Between the points of the clothing 4 a of the cylinder 4 on the one hand and the points of the clothing 3 a of the licker-in 3 3 there is a roller gap a. Between the points of the clothing 4 a of the cylinder 4 and, on the other hand, the points 5 a of the doffer there is further a roller gap b. When, during operation, heat is generated in the carding gap by the carding work, especially in the case of a high production rate and/or the processing of synthetic fibres or cotton/synthetic fibre mixtures, the cylinder casing 4 e is expanded, that is to say the radius r 3 increases and the roller gaps a and b become smaller. The heat is conducted by way of the cylinder casing 4 e into the radial supporting elements, the cylinder bases 4 c and 4 d . The cylinder bases 4 c , 4 d likewise expand as a result, that is to say the radius r 3 ( FIG. 2 ) increases. The cylinder 4 is virtually fully enclosed (encased) on all sides: in the radial direction by the elements 14 , 17 , 18 , 19 (see FIG. 1 ) and to both sides of the carding machine by the elements 23 a , 23 b ; 24 a , 24 b ; 25 a , 25 b . The machinery housing 34 comes in addition. As a result of the increase in the diameter of the cylinder 4 caused by thermal and/or centrifugal force expansion, the roller gaps a and b become smaller. As a result of the features according to the invention, the roller gaps a and b are increased again to the distances required for optimum carding. The roller gaps between the surfaces, or clothings, of neighbouring rollers are thus set or readjusted.
FIG. 4 shows the framework wall 23 a on one side of the carding machine; the framework wall 23 b (see FIG. 2 ) on the other side of the carding machine is basically of the same structure. The framework wall 23 a —preferably made of sheet steel—consists of a framework wall 23 , for the fibre feed, especially for mounting the feed device (feed roller 1 , feed table 2 ) and the lickers-in 3 1 to 3 3 , and of a framework wall 23 3 for mounting the fibre take-off elements, especially the doffer 5 . On the upper crossmembers of the framework walls 23 1 and 23 3 there are fixedly mounted inter alia the pivot bearing 27 a for the licker-in 3 3 and the pivot bearing 28 a for the doffer 5 (see FIGS. 5 a and 5 b ). Between the framework walls 23 1 and 23 3 there is located a framework wall 23 2 for mounting the cylinder 4 . The framework wall 23 2 consists of two vertical support struts 23 ′ and 23 ″ which are joined to one another at their upper end by a horizontal crossmember 23 ′″. On the crossmember 23 ′″ there is fixedly mounted the pivot bearing 26 a for the shaft 22 of the cylinder 4 . The framework walls 23 1 , 23 2 and 23 3 are joined to one another, for example by welding. The support struts 23 ′ and 23 ″ and the crossmember 23 ′″ project above the upper boundary of the framework walls 23 1 and 23 3 .
In each of the support struts 23 ′, 23 ″ (support columns), a heating rod 29 1 , 29 2 , respectively, is so arranged that the support struts 23 ′ and 23 ″ can be expanded or contracted in their longitudinal direction (that is to say in the vertical direction according to FIG. 4 ). The heating elements 29 1 and 29 2 are preferably arranged in the regions of the support struts 23 ′ and 23 ″ that project above the framework walls 23 1 and 23 3 , because in those regions—irrespective of the welded bonds—free expansion is possible. The expansion of the support columns 23 ′ and 23 ″ is only small and takes place exclusively within the material of the support struts 23 ′ and 23 ″. As mentioned previously, the framework wall 23 b on the other side of the carding machine is basically of the same structure and, in particular, includes correspondingly located heating rods.
In the embodiment of FIGS. 5 a and 5 b , before the carding machines are started into operation, for example at room temperature, there is a gap a between the cylinder 4 and the licker-in 3 3 on the one hand and a gap b between the cylinder 4 and the doffer 5 on the other hand, for example in each case 8/1000″. During operation of the carding machine, after the machinery, especially the rollers, has undergone heating, according to FIG. 5 a the gaps between cylinder 4 and licker-in 3 3 and between cylinder 4 and doffer 5 have been reduced to a 1 and b 1 , respectively, for example in each case 2/1000″. By means of the heating rods 29 1 and 29 2 shown in FIG. 2 and 4 (and—in a manner not shown—by means of the heating rods 29 3 and 29 4 in the support struts of the framework wall for the cylinder 4 in the framework wall 23 b on the other side of the carding machine) the support struts 23 ′ and 23 ″ are expanded in the vertical direction. As a result, the crossmember 23 ′″, the bearing 26 a (and the bearing 26 b not shown) and the axis 22 with the cylinder 4 are likewise raised upwards in the vertical direction. In this way the distance c 1 between the machinery or framework base and the centre point M of the shaft 22 ( FIG. 5 a ) is increased to the distance c 2 ( FIG. 5 b ). At the same time, the gaps a 1 and b 1 are increased to the gaps a 2 and b 2 , respectively, which can be determined by geometric calculation. The distances e 1 and d 1 between the machinery or framework base and the centre point of the shaft of the doffer 5 and the centre point of the shaft of the licker-in 3 3 remain the same.
T 1 =temperature cylinder 4 , licker-in 3 3 , doffer 5 T 2 =temperature side panels 24 a , 24 b T 3 =temperature framework 23
The temperature increases from the level of the rollers by way of the side panels as far as the machinery framework. In accordance with the invention, compensation for changes in the dimensions of the rollers is realised in a specific manner and with a low heat output.
The machinery framework 23 is so partitioned thermally that the cylinder 4 is raised by heating of its supports 23 ′, 23 ″, which are “insulated” from the remainder of the frame, measurements being taken of e.g. the cylinder temperature (T 1 ) and the framework temperature (T 3 ). The temperature (T 4 ) to be set can then be determined by means of a simple calculation (Δa=R×α×ΔT in which Δa is the change in the working gap, R is a constant, α is the angle subtended at the axis of the cylinder by a first plane containing the axes of the cylinder 4 and the doffer 5 and a second plane containing the axes of the licker-in 3 3 and the cylinder 4 ; and ΔT is the difference in temperature between the actual framework temperature and the target temperature T 4 .). The spacings a, b of the rollers can be kept constant by controlling (see FIG. 6 ) the temperature T 4 . By raising T 4 , the columns 23 ′, 23 ″ (support struts) become longer and the cylinder 4 is raised relative to the remainder of the framework. Depending upon the angle (α) and the temperature (T 4 ), the greater thermal expansion of the rollers relative to the framework is compensated.
The heating of the support struts 23 ′, 23 ″ (columns) can advantageously be effected using commercially available apparatus (heating rod 29 ).
The gaps between neighbouring rollers or between their clothing surfaces can be determined, for example, in the manner described in DE-A-39 13 996.
In the embodiment of FIG. 6 , for setting or readjusting the working gaps a and b there is provided an electronic control and regulating device 30 , for example a microcomputer having a microprocessor, to which a memory element 31 for predetermined working gaps a, b is connected. Furthermore, two measuring elements 32 , 33 for the working gaps a, b are connected to the control and regulating device 30 . The measuring elements 32 , 33 can detect the working gaps directly or indirectly. Four heating elements 29 a to 29 d are connected to the control and regulating device 30 . Measuring elements for the roller temperatures can be connected to the control and regulating device in a manner not shown.
Stepwise or stepless setting of the temperature of the heating elements 29 a to 29 d can be provided. As a result, supply and discharge of heat can be effected.
Although the foregoing invention has been described in detail by way of illustration and example for purposes of understanding, it will be obvious that changes and modifications may be practiced within the scope of the appended claims. | In a device on a carding machine for setting the working gap between the cylinder and a neighboring roller, which cooperate with one another with a working gap between their cylindrical surfaces at the fiber transfer points, the working gap is readjustable as a result of changes in dimensions caused by thermal expansion and/or centrifugal forces. If the dimensions of the rollers change, it is readily possible to set substantially the same gap between neighboring rollers. The temperature of the framework walls carrying the cylinder can be matched to the working gap by supplying or discharging heat. If the dimensions of the rollers change, the working gap substantially the same. | 3 |
RELATED APPLICATIONS
This application is a continuation of U.S. Non-Provisional Patent Application Ser. No. 12/266,197, filed on Nov. 6, 2008, which is a continuation in part of U.S. Non-Provisional Patent Application Ser. No. 11/983,078, filed Nov. 7, 2007, and U.S. Provisional Patent Application Ser. No. 60/857,300, filed Nov. 7, 2006, all of which are incorporated herein by reference in their entirety.
TECHNICAL FIELD OF THE INVENTION
The present invention relates to the process for catalytic cracking of petroleum oil. More particularly, the present invention relates to the application of advanced process control systems to catalytic cracking of petroleum oil in order to optimize the production of light olefins in relation to energy costs.
BACKGROUND OF THE INVENTION
In typical catalytic cracking techniques, the fluid catalytic cracking unit (FCC) cracks petroleum-derived hydrocarbons using a catalyst to achieve gasoline production. Although efforts are made to reduce side effects from the reaction, a small amount of unwanted products are produced, which include: liquefied petroleum gas (LPG), cracked gas oil and the like, and coke, which is deposited on the catalyst and thereby reduces the catalyst's effectiveness. The spent catalyst is regenerated by burning away the deposited coke using air and heat before the catalyst is recycled back into the process.
However, in recent years, there has been a shift towards using FCC units as a means for producing light olefins, such as propylene, rather than for primarily producing gasoline. Utilizing an FCC unit in this manner can be economically advantageous, particularly when the oil refinery is highly integrated with other steps throughout the oil production process.
Earlier methods for producing light-fraction olefins by an FCC unit using heavy-fraction oils included contacting feed oil with a catalyst for a short time (U.S. Pat. Nos. 4,419,221; 3,074,878; and 5,462,652; and European Patent No. EP 315,179A), carrying out the cracking at high temperatures (U.S. Pat. No. 4,980,053), and using pentasil-type zeolites (U.S. Pat. No. 5,326,465 and Japanese Patent National Publication (Kohyo) No. Hei JP 7-506389).
However, the methods taught by the above references failed to produce sufficient light-fraction olefins selectively. For example, the methods taught by using a reduced catalyst contact time resulted in a decrease in the conversion of light-fraction olefins to light-fraction paraffins due to the methods' inhibition of a hydrogen transfer reaction. Furthermore, the lack of hydrogen transfer also led to a decrease in the conversion of heavy-fraction oils to light-fraction oils. The method teaching the use of the high temperature cracking reaction resulted in a concurrent thermal cracking of heavy-fraction oils, which thereby increased the yield of low-value, dry gases. Lastly, the use of pentasil-type zeolites enhanced the yield of light-fraction hydrocarbons by excessively cracking the gasoline. Therefore, there was still a need to produce a light-fraction olefin without causing unwanted side effects.
U.S. Pat. No. 6,656,346 ('346) discloses an improved process for the fluid catalytic cracking of a heavy-fraction hydrocarbon to produce a high yield of light-fraction olefins, while simultaneously producing a diminished amount of unwanted dry gases. The process of '346 achieves its objective by contacting the heavy-fraction oil with a catalyst mixture that consists of a specific base cracking catalyst and an additive containing a shape-selective zeolite at a high temperature. Furthermore, '346 discloses that the catalyst mixture preferably contains between 60-95 wt % of the base cracking catalyst, with the additive making up the remainder. Additionally, the base cracking catalyst contains an ultra stable Y-type zeolite that has less than 0.5 wt % of rare-earth metal oxide.
Moreover, '346 teaches that in the reaction zone, the fluid catalytic cracking may be affected within a fluid bed, in which the catalyst particles are fluidized with the heavy-fraction oil, or, may be effected by employing so-called riser cracking, in which both the catalyst particles and the heavy-fraction oil ascend through a pipe, or, so-called down flow cracking in which both the catalyst particles and the heavy-fraction oil descend through a pipe. '346 goes on to teach down-flow type reaction zones are preferable over up-flow reaction zones in order to reduce the deleterious effects of back-mixing that occurs in up-flow reaction zones.
In spite of this breakthrough, the method taught by '346 has some disadvantages. Most glaringly is the difficulty in managing the multitude of variables that must be observed and manipulated throughout the production cycle. Since the crude oil feed varies in composition, it can be extremely challenging for operations personnel to manually test the properties of the incoming stream and adjust the necessary variables accordingly. Furthermore, because the process taught by the prior art is complicated and contains a variety of manipulatable variables, it is virtually impossible for an operator to manually control the process, even with remote access via a computer, and achieve an optimum yield of light olefins. Additionally, typical numerical methods and statistical analysis do not provide an acceptable level of process control. Consequently, the methods taught by the prior art do not teach a method for carrying out the process in an efficient manner and ensuring that the yield of light-fraction olefins has been maximized. Furthermore, no methods teach optimizing the production of light-fraction olefins in relation to energy usage.
SUMMARY OF THE INVENTION
The process of the present invention satisfies at least one of these needs. One embodiment of the present invention optimizes light olefin production, particularly propylene, in relation to energy usage for an FCC process by employing advanced process control, monitoring, and optimizing systems. In one embodiment of the present invention, process model and historical data are used in a predictive system to provide an early warning of potential equipment failure throughout the FCC unit. The present invention provides mathematical process models, including: neural networks, statistical models and finite impulse models. These various mathematical process models are used in conjunction with advanced controllers and optimizing routines to calculate optimal settings for various process parameters. Furthermore, in an embodiment of the present invention, a microwave based system is employed for optimizing the performance of a stripping zone, which further optimizes catalyst regeneration.
In one embodiment of the present invention, a process for the fluid catalytic cracking of a hydrocarbon feedstock includes the steps of reacting the hydrocarbon feedstock with a catalyst mixture in a continuous fashion in a reaction zone under reaction conditions to form a produced mixture, the produced mixture having a product stream and a spent stream, the catalyst mixture having a base cracking catalyst, an ultra stable Y-type zeolite, an unreacted catalyst stream, and a regenerated catalyst stream. The catalyst mixture having a catalyst feed rate, the hydrocarbon feedstock having a hydrocarbon feedstock feed rate, and the produced mixture having a produced mixture flow rate. Additionally, the reaction zone contains flow rate sensors, temperature sensors, control valves and a reactor. The flow rate sensors are operable to monitor the hydrocarbon feedstock feed rate, the catalyst mixture feed rate, and the produced mixture flow rate. The temperature sensors are operable to measure temperature within the reaction zone. The control valves are integrated with a process control system such that the process control system is operable to modify an amount of closure of the control valves such that the hydrocarbon feedstock feed rate, the catalyst mixture feed rate and the produced mixture flow rate are subject to manipulation. Furthermore, the reaction conditions include an operating temperature and a contact time of approximately 0.5 to 3 seconds. Following the reaction of the hydrocarbon feedstock and catalyst mixture, the produced mixture is separated into the product stream and the spent stream, with the spent stream being made up of spent catalyst and unreacted hydrocarbon. The spent stream is separated into spent catalysts and unreacted hydrocarbon, with the spent catalysts being transferred to a regeneration zone having a catalyst regenerator, where the spent catalysts are regenerated using an oxidation treatment to create the regenerated catalyst stream. The regenerated catalyst stream has decreased amounts of adsorbed material as compared to the spent catalyst. The spent catalyst has a flow rate and a residence time within the regeneration zone. The regenerated catalyst stream is recycled into the reaction zone, with the recycle rate being dependent on the regenerated catalyst stream's flow rate.
The process control system (PCS) is operable to control operating conditions of the FCC unit via control parameters. These control parameters include: obtaining predetermined process models; monitoring feed data, products characterization data, and operating conditions; selecting one of the predetermined process models based on the monitored feed data, monitored products characterization data and monitored operating conditions; selecting one of the predetermined process models based on the monitored feed data, monitored products characterization data and monitored operating conditions; calculating simulated-optimized-operating conditions using the selected predetermined process model; adjusting the operating conditions to correspond with the simulated-optimized-operating-conditions; measuring a propylene concentration in the product stream; measuring energy usage of the fluid catalytic cracking unit; comparing the propylene concentration with a predetermined propylene concentration range; comparing the energy usage of the fluid catalytic cracking unit with a predetermined energy usage range; and adjusting the operating conditions until propylene concentration falls within the predetermined minimum propylene specification to yield optimized propylene production. In one embodiment of the present invention, the optimized propylene production is defined as maximizing the ratio of propylene production over energy usage, with the energy usage being the energy consumed by the FCC unit.
The predetermined process models are operable to simulate operating conditions and produce simulated propylene production and simulated energy usage for the fluid catalytic cracking unit, wherein each predetermined process model is developed to simulate the fluid catalytic cracking unit for a specific range of operating conditions. The propylene concentration is compared with the predetermined propylene concentration range to determine whether the propylene concentration falls within the predetermined propylene concentration range. The energy usage of the FCC unit is compared with the predetermined energy usage range to determine whether the energy usage falls within the predetermined energy usage range.
BRIEF DESCRIPTION OF THE DRAWINGS
So that the manner in which the above-recited features, advantages, and objectives of the invention, as well as others that will become apparent, are attained and can be understood in detail, more particular description of the invention briefly summarized above may be had by reference to the embodiments thereof that are illustrated in the drawings that form a part of this specification. It is to be noted, however, that the appended drawings illustrate only preferred embodiments of the invention and are, therefore, not to be considered limiting of the invention's scope, for the invention may admit to other equally effective embodiments.
FIG. 1 is a network for constructing system mapping.
FIG. 2 is a schematic diagram of a generic fluid catalytic cracking process equipped with various control systems in accordance with one specific embodiment of the present invention.
FIG. 3 is a schematic diagram of Distributed Control System utilized in one specific embodiment of the present invention.
FIG. 4 is a schematic flow diagram of a generic fluid catalytic cracking process equipped with various control systems in accordance with one specific embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The invention will be described below in more detail.
Neural Networks Modeling
Without loss of generality, a nonlinear system can be defined as
y ( t )=ƒ[ Y ( t− 1), Y ( t− 2), . . . , Y ( t−n y ), U ( t− 1), U ( t− 2), . . . U ( t−n u )]+ e ( t ) (1)
where n y and n u are the maximum lags in the output vector and the input vector e(t) is the noise. The MLP network for constructing the system mapping ƒ(•) is shown in FIG. 1 .
FIG. 1 shows three layers, but more layers are a direct generalization. The input layer has n i =n y M+n u N neurons, where M is the number of outputs and N is the number of inputs. The input vector is then defined as below:
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Thus, the input vector of the network consists of the past values of the network and output vector of the system. The input layer simply feeds the vector U(t) to the hidden layer without any modification. The hidden layer has user-defined n h neurons with nonlinear transfer functions (such as sigmoid function). The output of the network is represented as:
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Ŷ ( t )=[ ŷ 1 ( t ), ŷ 2 ( t ), . . . , ŷ M ( t )] (5)
and the error is defined as:
E ( t )= Y ( t )− Ŷ ( t ) (6)
The weights are updated by using a back propagation algorithm. It is expressed as follows:
w ji (l) ( t+ 1)= w ji (l) ( t )+ηδ j (l) ( t )q i l−1 ( t ) (7)
where the δ j for the neuron j in output layer L and in hidden layer l are given by (8) and (9) respectively.
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β (l) j ( t+ 1)=β j (l) ( t )+δ j (l) for h= 1, 2 (10)
Feed-Forward Neural Networks (FFNN)
The use of feed-forward neural networks (FFNN) in system identification has been growing in recent years. In 1990, Narendra and Parthasarathy demonstrated that FFNN could be used effectively for identification and control. They applied both static and dynamic back propagation methods for the adjustment of network parameters. The same year, Bhat, Minderman, McAvoy and Wang used neural networks for modeling nonlinear chemical process systems such as a steady-state reactor and a dynamic pH continuously stirred tank reactor. Bhat et al. used the back-propagation algorithm for interpreting biosensor data by utilizing FFNN modeling. In 1991, Tai, Helen, Ryaciotaki and Hollaway presented a survey report on the algorithms and techniques of neural networks implemented in the areas of identification, robotics, detection, adaptive control, modeling and optimization. Tai et al. discussed five algorithms used by researchers to train neural networks for identification and control. The five algorithms included: supervised learning, inverse dynamics, stabilization, propagation through time, and adaptive critic systems. Lee, Park, Kishan, Chilukuri and Ranka compared the performance of FFNN and RNN (recursive neural networks) in system identification and inverse system identification by simulation. Both of these networks were used to build an emulator for a simple, nonlinear gantry crane system and also to calculate the inverse dynamics of the system.
The lack of generic and efficient methodology for nonlinear system identification with an unknown system architecture prompted Qin, Su and McAvoy to re-derive pattern learning and batch learning rules for both FFNN (multilayer perceptrons) and RNN respectively. This was one of the pioneering works in black box modeling vis-à-vis neural networks. Chen and Mars discussed the feasibility of using MLP neural networks for system identification. They scrutinized the work of Narendra et al. and provided some solutions to the constraints pointed out in that work. Stader compiled most of the learning strategies and neural network architectures and discussed their theoretical foundations and limitations in the areas of prediction and modeling. In 1993, Yamada and Yabuta proposed practical design methods for the identification of both the direct and inverse transfer functions of a nonlinear dynamic system through the use of neural networks. In 1994, Sjoberg utilized FFNN based NNARX modeling techniques to simulate different nonlinear systems having different kinds of non-linearities.
Definitions
As used herein, neural network (NN) is an interconnected group of artificial neurons that uses a mathematical or computational model for information processing based on a connectionistic approach to computation. In most cases an NN is an adaptive system that changes its structure based on external or internal information that flows through the network. Other common names for a neural network include artificial neural network (ANN) and simulated neural network (SNN).
As used herein, the term fluid catalytic cracking (FCC) indicates that heavy-fraction oil is continuously brought into contact with a catalyst that is kept in a fluidized state in order to crack the heavy-fraction oil, thereby producing light-fraction hydrocarbons, comprising mainly gasoline and light-fraction olefins.
As used herein, “reaction outlet temperature” is defined as an outlet temperature of the up flow-type reaction zone, and it is the temperature before separation of the cracked products from the catalysts.
As used herein, catalyst/oil ratio is a ratio of the amount of the catalyst mixture recycled (ton/hr) to a rate of the feed oil fed (ton/hr).
Brief Overview of Apparatus and Process
The FCC apparatus that can be used in this invention has a regeneration zone (a regenerator), an up flow-type reaction zone (a riser reactor), a separation zone (a separator), and a stripping zone (a stripper). The reaction zone is also equipped with multiple sensors to monitor the product and feed composition on-line and is integrated with a control system, as well as means to control catalyst loading and discharge in real-time based on reactor performance.
In the reaction zone, heavy-fraction oil is continuously brought into contact with a catalyst mixture, which is maintained in a fluidizing state, to crack the heavy-fraction oil and thereby produce light-fraction hydrocarbons, which are mainly comprised of light-fraction olefins. A mixture of catalysts, hydrocarbon gas, which contains products obtained by the catalytic cracking, and un-reacted materials are forwarded into the separation zone, wherein most of the catalyst is separated from the mixture.
The separated catalysts are then forwarded to the stripping zone, wherein most of the adsorbed material on the catalyst is removed. The stripped catalysts, along with a small portion of heavy hydrocarbons, are forwarded to the regeneration zone, wherein the stripped catalysts are subjected to an oxidation treatment, further decreasing the amount of adsorbed material, and yielding regenerated catalysts. These regenerated catalysts are continuously recycled to the reaction zone.
Feed Oil
In the FCC unit of this invention, heavy-fraction oil is used as feed oil. The heavy-fraction oil used preferably has a boiling point, at atmospheric pressure, in the range of 250° C. or higher. The heavy-fraction oil used herein may include straight-run gas oil, vacuum gas oil, atmospheric residue, coker gas oil, or petroleum oils obtained by hydrofining or hydrotreated said residues and gas oils. These aforementioned petroleum oils may be used singly or as a mixture thereof, with a minor portion of light fraction oil.
Catalyst Design
A catalyst's physical and chemical properties contribute to increased conversion through selectivity differences. These include zeolite type, pore size distribution, relative matrix to total surface area, and chemical composition. The amount of catalyst used i.e., catalyst/oil ratio is significant for maximum olefins production.
The propylene production of a fluid catalytic cracking unit employing a large pore zeolite cracking catalyst produces more propylene by adding a cracker riser and a medium pore zeolite catalytic component to the unit, and recycling at least a portion of the cracked material to the cracker riser. The large pore size zeolite preferably comprises an ultra stable Y-type zeolite and the medium pore size is preferably ZSM-5.
At least a portion of the hydrocarbon is converted to produce an olefin having about two to about three carbon atoms per molecule. The large pore zeolite component is preferably a faujasite type and more preferably a Y type faujasite. The medium pore zeolite component is preferably a ZSM-5 type. In addition to the large and medium pore size zeolite components, the catalyst can also include at least one porous, inorganic refractory metal oxide as a binder. It is preferred that the binder have acid cracking functionality, for cracking the heavier components of the FCC feed and that the medium pore size zeolite component comprise at least 1 wt % of the catalyst, on a total weight basis.
In another embodiment, the catalyst can include large pore size zeolite particles and medium pore size zeolite particles. Both the large and medium pore size zeolite particles are composite materials with a porous, inorganic refractory metal oxide binder. In another embodiment, the zeolite-containing catalyst typically includes at least 0.5 wt % to about 10 wt % phosphorus and about 0.1 wt % to about 10 wt % of a promoter metal selected from the group consisting of gallium, germanium, tin and mixtures thereof.
The zeolite can be treated with about 10 wt % of the phosphorus-containing compound, (calculated as P 2 O 5 ) based on the total amount of olefin-selective zeolite, to ensure proper light olefin selectivity. After treatment with the phosphorus-containing compound, the treated olefin-selective zeolite is dried and subsequently calcined at a temperature between 300° C. and 1000° C., preferably between 450° C. and 700° C. for about 15 minutes to 24 hours, to prepare the suitable olefin-selective “cracking catalyst.”
The catalysts on which carbonaceous materials, and a portion of heavy hydrocarbons, are deposited, are forwarded from the stripping zone to the regenerating zone. In the regenerating zone, the catalysts, on which the carbonaceous materials and the like are deposited, are subjected to oxidation treatment, to decrease the amount of the deposits, thereby obtaining regenerated catalysts. These regenerated catalysts are continuously recycled to the reaction zone. The cracked products are quenched just upstream of, or just downstream of, the separator, in order to avoid unnecessary further cracking or excessive cracking.
The catalyst mixture which is used in this invention can contain a base cracking catalyst and an additive. In one embodiment, the base cracking catalyst includes a stable Y-type zeolite, which is the main active component of the base catalyst, and a matrix, which is a substrate material for the zeolite. The base cracking catalyst contains less than 0.5 wt % of rare-earth metal oxide that is mainly included in the ultra stable Y-type zeolite. Generally, catalytic activity of stable Y-type zeolites increases as the rare-earth metal content in the zeolites increases because thermal stability of the ultra stable Y-type zeolite is improved by incorporating rare-earth metal into the zeolites.
Hydrogen transfer reaction activity of the Y-type zeolites is also increased by adding rare-earth metal to the zeolites. The content of the stable Y-type zeolite in the base cracking catalyst used in this invention is preferably in a range of 5 to 50 wt %, more preferably in the range of 15 to 40 wt %. The term “stable” Y-Type zeolite includes such zeolite material such as “ultrastable” zeolitic materials.
The matrix of the base cracking catalyst used in this invention may include clays such as kaolin, montmorilonite, and bentonite, and inorganic porous oxides such as alumina, silica, magnesia, and silica-alumina. The base cracking catalyst used in this invention preferably has a bulk density of 0.5 to 1.0 g/ml, an average particle diameter of 50 to 90 microns, a surface area of 50 to 350 m 2 /g, and a pore volume of 0.05 to 0.5 ml/g.
The catalyst mixture used in this invention contains, in addition to the base cracking catalyst, an additive containing a shape-selective zeolite. The shape selective zeolite referred to herein means a zeolite whose pore diameter is smaller than that of the Y-type zeolite so that hydrocarbons with only limited shape can enter the zeolite through its pores. Examples of the shape-selective catalysts are: ZSM-5, omega, SAPO-5, and aluminosilicates. Among these shape-selective zeolites, ZSM-5 zeolite is most preferably used in this invention. The content of the shape-selective zeolite in the additive used in this invention is preferably in the range of 20 to 70 wt %, more preferably in the range of 30 to 60 wt %.
A percentage of the base cracking catalyst in the catalyst mixture used in this invention is in a range of 60 to 95 wt %, and a percentage of the additive in the catalyst mixture used in this invention is in a range of 5 to 40 wt %. If the percentage of the base cracking catalyst is lower than 60 wt % or the percentage of additive is higher than 40 wt %, high light-fraction olefin yield cannot be obtained, because of low conversions of the feed oil. If the percentage of the base cracking catalyst is higher than 95 wt %, or the percentage of the additive is lower than 5 wt %, very high light-fraction olefin yield cannot be obtained, while high conversion of the feed oil can be achieved. In a particularly preferred embodiment, the catalyst contains at least 0.5 wt. % P, typically present as P 2 O 5 .
In this invention, commercially available “cracking catalyst” such as OCTACAT (W. R. Grace Co., Ltd.) can be used. The OCTACAT contained a zeolite having a crystal lattice constant of 24.50 Å. Other suitable commercially available “cracking catalysts” include the following name or brands: Akzo Novel, Engelhard, DuPont, HARMOREX (CCIC), OlefinsMAX (by Davison), Tosco, etc., Stone & Webster, UOP and others.
Catalyst Oil Ratio
Increasing the concentration of catalyst, often referred to as catalyst/oil ratio, in the reaction zone will increase the availability of cracking and result in maximum conversion. In the present invention, increasing the catalyst/oil ratio can be achieved by either increasing the reaction zone heat load or switching to a lower coke selective catalyst (i.e., lower delta coke). Reaction zone heat load can be raised by increasing the reactor temperature or by lowering feed rate.
In an embodiment of the present invention, the catalyst/oil ratio can be in the range of 10 to 40 wt/wt, preferably in the range of 20 to 30 wt/wt. If the catalyst/oil ratio is less than 15 wt/wt, a catalyst-dense-phase temperature in the regeneration zone will arise, caused by the local heat balance. This in turn accelerates the deactivation of the catalyst simultaneously with the feed oil being brought into contact with those catalyst particles having the higher temperature, which in turn increases thermal cracking and leads to an increased amount of unwanted dry gases.
Furthermore, if the catalyst/oil ratio exceeds 40 wt/wt, the handling capacity of the regeneration zone will need to be increased to handle a larger volume of recycled catalyst in order to provide the optimal catalyst residence time therein.
Carbon on Regenerated Catalyst
The lower the carbon on regenerated catalyst, CRC, the higher the availability of cracking sites since less coke is blocking acid cracking sites. CRC is reduced by increasing regeneration efficiency through the use of carbon monoxide oxidation promoters. Increased regenerator bed levels also improve CRC through increased residence time but this must be traded off with reduced dilute phase disengager residence time and the possibility for increased catalyst losses.
Catalyst Feed Rate
The catalyst is added periodically in this invention to the FCC unit based on a predefined production schedule. The timing and quantity of catalyst injected can be pre-programmed into the controller with provisions for augmentation during operation of the FCC process to optimize the production yield, product mix or emissions control. However, due to the uncertainties of the production process, such as: chemical make-up of the oil feed stock and other variations entering the FCC system, emissions, and energy use, the product mix may vary or drift from process targets during the course of fluid-cracking.
In one embodiment of the present invention, the catalyst feed rate is controlled and monitored by a monitoring system. However, the feed rate is dependent on the feed composition, and the optimum feed rate is predicted by the model.
Reaction Time
An increase in reaction time available for cracking also increases conversion. Fresh feed rate, riser steam rate, recycle rate and pressure are the primary operating variables that affect reaction time for a given unit configuration. Conversion varies inversely with the rate due to limited reactor size available for cracking. Conversion has been observed in some units to increase by only 1% absolute for a 3 to 5% relative decrease in fresh feed rate. The contact time referred to herein means either the time between the start of contact of the feed oil with the regenerated catalysts and the separation of the produced cracked products from the catalysts, or the time between the start of contact of the feed oil with the regenerated catalysts and the quenching of the produced cracked products.
In the present invention, the contact time is in the range of 0.1 to 1.0 seconds, preferably in the range of 0.2 to 0.7 seconds. If the contact time is less than 0.1 seconds, then the light-fraction olefins will have a lower yield due to the low conversion of the heavy fraction oil. Conversely, if the contact time exceeds about one (1) second, then the thermal cracking of petroleum oil fed will be excessive, thereby excessively increasing the amount of dry gases generated. However, the contact time is dependent on the feed system, and the optimum reaction time is predicted by the model.
Reactor Temperature
Increased reactor temperature increases unit conversion, primarily through a higher rate of reaction for the endothermic cracking reaction and also through increased cat/oil ratio. An increase of approximately 10° F. in reactor temperature can increase conversion by about 1-2% absolute. A higher reactor temperature also increases gasoline octane and LPG olefinicity, which are very desirable side benefits of maximizing conversion via reactor temperature. The higher octane is due to the higher rate of primary cracking reactions relative to secondary hydrogen transfer reactions which saturate olefins in the gasoline boiling range, thereby lowering gasoline octane. Generally, an increase of approximately 10° F. in reactor temperature can give up to about a 0.8 and 0.4 number increase in research and motor octane, respectively.
Under a very short residence time, the desired reaction zone outlet temperature is in the range of 570° C. to 630° C., preferably in the range of 590° C. to 620° C. If the reaction zone outlet temperature is lower than 570° C., then the light-fraction olefins will not have a high yield. Conversely, if the reaction zone outlet temperature is higher than 630° C., a significant increase in the amount of dry gases is generated due to excessive thermal cracking of the heavy fraction feed oil.
If naphtha is the feedstock for a particular application, the reaction temperature can be lowered compared to residue cracking to optimized propylene production. However, the reaction temperature and time are dependent on the feed system and the optimum conditions are predicted by the model.
Pressure
Higher conversion and coke yield are thermodynamically favored at higher pressures; however, the conversion is not significantly affected by unit pressure since a substantial increase in pressure is required to significantly increase conversion. In an embodiment of this invention, the apparatus can be operated preferably at a reaction pressure of about 1 to 3 atm and at a regenerating zone temperature of 650° C. to 720° C.
Reactor.
The fluid catalytic cracking unit is used in this certain embodiments invention can include a regeneration zone (a regenerator), an up flow-type reaction zone (a riser reactor or “riser”), a separation zone (a separator), and a stripping zone (a stripper). The reactor can also be equipped with multiple sensors to monitor product and feed composition on-line and is integrated with a control system, as well as means to control catalyst loading and discharge real-time based on reactor performance.
Heat Balance
Coke formation in an FCC unit can be the most critical parameter to maintain the heat balance. Coke produced in the riser is burnt in the presence of air in the regenerator. The heat produced through exothermic coke burning reactions supplies the heat demands of the reactor, i.e., heat of vaporization, and associated sensible heat of the feedstock, endothermic heat of cracking, etc. For example, the coke yield in a conventional FCC unit with vacuum gas oil remains can be in the range of approximately 4.5-5.5 wt %. The heat produced from complete combustion can be sufficient to supply the reactor heat load. However, in a residue FCC unit, because the feedstock contains large amounts of coke precursors with higher amounts of Conradson coke and aromatic rings, the coke formation can be significantly increased, which in turn increases the regenerator temperature from approximately 650° C.-860° C. in conventional FCC units to approximately 720° C.-250° C. in residue crackers.
Optional Advanced Energy Source
Microwave frequency ignores the catalytic cracking catalyst and preferentially excites the hydrocarbon on the spent catalyst, the stripping steam conventionally used, or both the stripping steam and the hydrocarbonaceous coke. Ultrasonic energy, such as cavitations, is also a suitable energy source for coke removal. In preferred embodiments, microwave frequencies that are selective towards polar compounds, such as sulfur and nitrogen, are used. Additionally, using cavitations to remove carbonaceous material from the catalyst will occasionally result in a beneficial cracking of the carbonaceous material; leading to an increase in desirable products.
The process of the present invention provides a means for stripping entrained hydrocarbons from the catalyst. The microwave (MW) or sonic stripping section can be easily installed in the present invention. A number of variations can be incorporated using multiple MW/Sonic sources in the stripping section. The stripping section can be optionally lined with a material that reflects the selected microwave (MW) or sonic radiation. This additional lining would ensure that the MW/Sonic energy is used for hydrocarbons and/or undesirable heteroatoms such as sulfur and nitrogen compounds, rather than be used to heat up the steel stripper vessel. In one embodiment, most of the MW/Sonic energy is focused on a relatively dense phase region of the stripper, which permits a longer residence time. Although this concept will be suitable for many installations, it should not be considered limiting.
In a preferred embodiment, the MW/Sonic stripper includes multiple stages, which give the process the ability to remove stripped products at multiple points in the stripping operation. With the ability to selectively heat hydrocarbons, and/or sulfur and nitrogen compounds afforded by the present invention, use of extremely short residence time stripping is now possible.
Stripping techniques heretofore used to de-water paper pulp are now applicable to catalytic stripping processes. In other words, subsequent to the microwave exposure, the catalyst is passed over a relatively large cross-sectional area surface with a vacuum on one side of the surface to aid in the stripping operation. In one embodiment, porous stainless steel filters can be used. In another embodiment, annular flow of catalyst around a porous stainless steel filter can be used to strip hydrocarbons and/or sulfur and nitrogen compounds from catalyst which has been exposed to MW/Sonic energy.
Control of Operating Conditions and Variables
In one aspect, the invention is aimed to “optimize propylene production,” which means to “maximize propylene production at the minimum energy usage.” Hydrocarbon conversion in an FCC unit can be a complicated function of many variables. For example, over-cracking of gasoline to LPG and dry gas may occur due to an increase in reactor residence time. Available approaches to offset any potential over-cracking include adding additional riser steam to lower hydrocarbon partial pressure for more selective cracking, reducing reactor pressure, increasing the recycle rate to decrease residence time, reducing the availability of catalytic cracking sites by lowering cat/oil ratio, and by combinations of the foregoing conditions.
The variables described above are generally not optimized for maximizing conversion of propylene in existing FCC units. Optimum conversion level corresponds to a given feed rate, feed quality, set of processing objectives, and catalyst at other unit constraints (e.g., wet gas compressor capacity, fractionation capacity, air blower capacity, reactor temperature, regenerator temperature, catalyst circulation). Therefore, the FCC operator needs to adjust several variables at the same time. If the, optimum conversion level is found, only then can the operator work on the suitable catalyst and perhaps redesign the catalyst properties to remove operating constraints to shift the operation to a higher optimum conversion level. However, there is lack of suitable automation process equipment that can be readily used to optimize such performance
On-line Performance Monitoring
Regulatory control loops serve as the foundation of the plant automation hierarchy. Maintenance and control-engineering personnel struggle to sustain the performance of the conversion assets. Equipment and technology reliability issues, changing plant business drivers, and fewer skilled resources to monitor and maintain these assets are all cited as common problems. The results include negative impacts to quality, energy consumption, equipment wear and tear, plant throughput, and ultimately, profitability. Performance monitoring will provide tools to (1) benchmark current control performance against industry standards, (2) identify & prioritize problems to focus maintenance resources, (3) analyze and diagnose problems with online and offline reports, (4) improve control performance with a complete set of tools for both regulatory and advanced controllers, and (5) monitor to sustain improvements with comprehensive, automated reporting. Tools such as Matrikon's ProcessDoctor, Honeywell's LoopScout, or Yukogawa's MD Diagnostic are examples which provide such functionalities.
Modeling and Optimization Package
Advanced software to improve throughput and control of continuous processes that have incipient disturbances can be used to optimize the FCC unit. Such software packages offer automatic control over continuous processes that are difficult to control by conventional automation techniques. There are many processes that are subject to disturbances whose onset is too fast for conventional manual or automatic control to react. The use of modeling and optimization packages results in increased throughput and reduced energy usage through superior control during normal operation, and also through avoidance or mitigation of process upsets that can shut down the process. It also requires less manual intervention from human operators responsible for the process, so they can focus their attention on higher-level production control activities. Certain embodiments of the present invention can utilize a software package, such as for example, Umetric's SIMCA P11 and the optimization tools in Matlab by MathWorks Inc.
Many of the above mentioned packages provide an optimization routine, which is defined as minimization of math functions which include representation of the process and product and energy costs.
Detection of Operating Conditions and Selection of Process Model
In one specific embodiment of the present invention, the system can use various sensor signals to determine the operating conditions and select the process model that best represents the current operations. The model can be selected from a list of previously developed process models. The selected model can then be used in the optimization algorithm to calculate the optimal process settings.
Referring now to FIG. 2 , the proposed catalytic cracking process can be optionally equipped with various control systems (“Process Control”). Further, the FCC processes can be equipped with all or some of the following features, as deemed necessary as described.
The signals from a FCC unit [ 60 ] are introduced into a Distributed Control System (“DCS”) [ 10 ], a process control system that uses a network to interconnect sensors, controllers, operator terminals and actuators. A DCS [ 10 ] includes a computer and has interconnections with other systems.
Model Predictive Control (“MPC”) [ 30 ], is an advanced method of process control that improves on standard feedback control by predicting how a process such as distillation will react to inputs such as heat input. This means that feedback can be relied on much less since the effects of inputs will be derived from mathematical empirical models. Feedback can be used to correct for model inaccuracies. The controller relies on an empirical model of a process obtained by plant testing to predict the future behavior of dependent variables of a dynamical system based on past responses of the independent variables. Frequently, the controller relies on linear models of the process.
Major commercial suppliers of MPC software include the AspenTech (DMC+), Honeywell (RMPCT) and Shell Global Solutions (SMOC; Shell Global Solutions inc: Carel van Bylandtlaan 23, 2596 HP, The Hague, The Netherlands).
Control Loop Performance Monitoring (“CLMP”) (not shown). Performance monitoring allows (1) benchmarking current control performance against industry standards, (2) identifying & prioritizing problems to focus maintenance resources, (3) analyzing and diagnose problems with online and offline reports, (4) improving control performance with a complete set of tools for both regulatory and advanced controllers, and (5) monitoring to sustain improvements with comprehensive automated reporting. Exemplary tools such as Matrikon's ProcessDoctor (available from Matrikon's located at 10405 Jasper Avenue, Edmonton, Alberta, Canada), Honeywell's Profit Expert (available from Honeywell International Inc., 101 Columbia Road, Morristown, N.J. 07962), or Yukogawa's MD Diagnostic (Yukogawa, Musashino-shi, Tokyo, Japan) and Aspentech's (Aspen Technology, Inc., Ten Canal Park, Cambridge, Mass.) AspenWatch provide such functionalities.
Detection of operating conditions and Selection of Process Model (“SPM”) [ 40 ]. This system uses sensor signals in the process to determine the operating conditions such as current feed rate, feed composition, and ambient temperature to select the process model that best represents the current operation. This selected process model can then be used in the optimization algorithm to calculate the optimal process settings. The tools can be developed in Matlab (Mathworks Inc., 3 Apple Hill Drive, Natick, Mass. 01760-2098), Visual Basic code or other software programming language.
Real Time Optimization and Dynamic Optimization (“RTO”) [ 30 ]. The optimization of industrial process systems is one way of adjusting the process control variables to find the reaction conditions that achieve the highest propylene yield with minimum cost or other possible outcome. Usually, many conflicting responses must be optimized simultaneously. In the lack of systematic approaches, optimization can be done by “trial-and-error” or by changing one control variable at a time while holding the rest constant. Such methods are generally not efficient in finding the true optimum. Usually, optimization techniques involve development of rigorous process models. These mathematical models can include chemical reactions and thermodynamic equations. Exemplary tools such as PAS Inc.'s (16055 Space Center Blvd., Houston, Tex. 77062, USA) NOVA provide such functionalities. The models can be validated against plant operation data to verify the model accurately represents the plant behavior. These models are dynamic in the sense they model the time of change of process variables.
Energy Management Technology (“PMS”) [ 70 ]. PMS balances energy requirements with the available energy supply, and thus prevents disturbances of operations, or even blackouts. Furthermore, the PMS can enable better control of energy costs, enhanced safety and the mitigation of environmental impacts. ABB Ltd, (Affolternstrasse 44 P.O. Box 8131, CH-8050 Zurich, Switzerland) is believed to be one provider of such technology.
Field Bus Technology (“FFS”). The field signals used in process instrumentation have been standardized, allowing control systems and field devices from a variety of suppliers can be interconnected using standard 4 to 20 mA analog signals. The FOUNDATION fieldbus™ standard developed by the Fieldbus Foundation™ constitutes the next level of standardization and it is designed to meet modern needs. In addition to having interconnectivity equivalent to that available using 4 to 20 mA analog signals in a conventional field network, FOUNDATION fieldbus™ allows multiple devices to be connected to a single FOUNDATION fieldbus™, permits the interactive communication of various types of information, and enables the distribution in the field of intelligent functions including self-diagnostics and control functionality. The focus is on its ability to transmit various types of information in addition to field signals and to distribute intelligence to distributed field devices. These features enable remote monitoring, real-time self-diagnostics, and proactive maintenance of field devices, as well as plant resource management using field communication. This can greatly reduce operating instrumentation systems costs. Emerson Corporate, (P.O. Box 4100, 8000 West Florissant Avenue, St. Louis, Mo.) is an exemplary provider of these technologies.
FCC Unit Profit and Energy Cost Calculation (“FUPEC”) [ 50 ] includes calculations that allow for using various process data, such as for example, FCC steam, catalyst, electricity and products costs to be monitored and/or calculated, thereby allowing for real-time monitoring the dollar cost per unit of products generated by the FCC unit.
In certain embodiments, the processes can be automatically monitored and adjusted as necessary. The performance monitoring of the proposed high severe fluid catalytic cracking conversion process can provide tools to: (a) benchmark current control performance against desired standards; (b) analyze and diagnose problems with online monitoring and control; (c) improve control performance with a complete set of advanced controllers and tools; (d) monitor to sustain improvements with comprehensive, automated reporting; and (e) remotely monitor using multiple sensing units and make adjustments on catalyst injections and other operating conditions to the system outputs while reducing the reliance on human interactions such as monitoring and manual changes to the catalyst injection schedule and other process variables. Such systems can be built by many commercial venders, such as those identified above, and can be integrated into the FCC unit [ 60 ]. In certain embodiments the monitoring systems can include sensors which may be positioned throughout the FCC unit [ 60 ] to monitor feed and product characteristics and reaction conditions. In certain embodiments, the sensors can communicate with the DCS control system [ 10 ] via hard wired connections to the system. In certain other embodiments, the sensors can be configured to communicate with the DCS control system [ 10 ] via wireless or RFID communication means. Thus, as shown in FIG. 4 , while the DCS unit is not shown to be hardwired the flow control valves or sensors present in the FCC unit [ 60 ], it is understood that the DCS [ 10 ] is operatively coupled to the FCC unit [ 60 ].
Referring now to FIG. 4 , hydrocarbon feedstock [ 102 ] is charged to the bottom of reaction zone [ 100 ]. Hot regenerated catalyst stream is added via conduit [ 104 ], equipped with a regenerated catalyst control valve [ 106 ]. A lift gas can be introduced near the liquid and solid feed inlets by means not shown. Additionally, an optional fresh catalyst stream can be added via conduit [ 103 ]. The hydrocarbon feedstock vaporizes and forms a dilute phase suspension with the FCC catalyst. The suspension passes up the reaction zone [ 100 ], which generally gets wider to accommodate volumetric expansion. Cracked products and coked catalyst may pass into a solid-vapor separation means, such as a conventional cyclone.
A means for stripping entrained hydrocarbons from the catalyst is provided in stripper [ 108 ]. Preferably some conventional stripping steam is added via line [ 110 ]. The microwave (MW) or a sonic stripping section [ 112 ] shown in FIG. 4 is a simple representation of an embodiment of the present invention. A number of variations can be incorporated using multiple MW/Sonic sources as shown by [ 112 ] which radially apply the energy in the stripping section.
The stripper [ 108 ] is optionally lined with a material which reflects the selected microwave (MW) or sonic radiation, to ensure that the MW/Sonic energy is used for the hydrocarbons, and undesirable heteroatoms such as and sulfur and nitrogen compounds, and not wasted in heating up the steel stripper vessel.
In one embodiment of the present invention, most of the MW/Sonic energy is applied in a relatively dense phase region of the stripper, which permits a longer residence time. Although the concept shown in the embodiment of the drawing will be the suitable for many installations, it should not be considered limiting.
In new units, the use of a multi-stage MW/Sonic stripper, with the ability to remove stripped products at multiple points in the stripping operation, is highly preferred. With the ability to selectively heat hydrocarbons, and/or sulfur, and nitrogen compounds afforded by embodiments of the present invention, use of extremely short residence time stripping is now possible. Stripping techniques heretofore used to de-water paper pulp are now applicable to catalytic stripping processes. By this is meant that the catalyst, after microwaving, could be passed over relatively large cross-sectional area surfaces with a vacuum on one side of the surface to aid in stripping operation. Porous stainless steel filters can be used. In another embodiment, annular flow of catalyst around a porous stainless steel filter can be used to strip hydrocarbons and/or sulfur and nitrogen compounds from catalyst which has been exposed MW/Sonic stripper.
Cracked products and stripper effluent vapors are combined to form a produced mixture. The produced mixture is withdrawn from reaction zone [ 100 ] by conduit [ 114 ]. Stripped catalyst containing coke is withdrawn via conduit [ 122 ] and charged to regeneration zone [ 120 ]. The flow rate of the stripped catalyst is controlled using stripped catalysts control valve [ 134 ]. The catalyst is regenerated by contact with a regeneration gas [ 124 ]. Regeneration gas [ 124 ] is an oxygen-containing gas, usually air. Flue gas is withdrawn from the regenerator by line [ 126 ]. Catalyst circulates from coke combustor [ 128 ] to second dense bed [ 130 ]. Some catalyst is recycled to the base of coke combustor [ 128 ] via line [ 132 ].
Conditions in fractionator [ 140 ] can be conventional. Usually the produced mixture will be preheated to about 150° C. to 375° C. In one embodiment, regeneration zone [ 120 ] operates at about 650° C. to 750° C. and the catalyst to feed weight ratio is usually about 4:1 to 8:1, adjusted as necessary to hold a desired reaction zone outlet temperature usually about 450° C. to 550° C.
Produced mixture from the FCC unit passes via line [ 114 ] to fractionator [ 140 ], where produced mixture is separated into a heavy, slurry oil stream [ 142 ], heavy cycle oil [ 144 ], light cycle oil [ 146 ], naphtha [ 148 ], and a light overhead stream [ 150 ]. The light overhead stream [ 150 ] is rich in C 2 -C 4 olefins, C 1 -C 4 saturates, and other light cracked gas components. This light stream is usually treated in an unsaturated gas plant to recover various light gas streams, including C 3 -C 4 LPG, and optionally C 2 -fuel gas or the like.
In embodiments of the present invention, control valves [ 106 , 134 , and 136 ] are operatively coupled with DCS [ 10 ] in order to control the flow rates of their respective streams. In another embodiment, all input streams are fitted with sensors as well control valves (not all control valves and sensors are shown in FIG. 4 ). The sensors are operable to measure the flow rates and temperatures of their respective stream. Moreover, the sensors are operatively coupled with DCS [ 10 ] as shown by the dashed lines.
Having described the invention with reference to particular compositions, theories of effectiveness, etc., it will be apparent to those of ordinary skill in the art that it is not intended that the invention be limited by such illustrative embodiments or mechanisms, and that modifications can be made without departing from the scope or spirit of the invention, as defined by the appended claims. It is intended that all such obvious modifications and variations be included within the scope of the present invention as defined in the appended claims. The claims are meant to cover the claimed components and steps in any sequence which is effective to meet the objectives there intended, unless the context specifically indicates to the contrary. The specific process examples herein disclosed are to be considered as being primarily illustrative. Various changes beyond those described will no doubt occur to those of ordinary skill in the art; and such changes are to be understood as forming a part of this invention insofar as they fall within the spirit and scope of the claims. | Petroleum oil is catalytically cracked by contacting oil with catalyst mixture consisting of a base cracking catalyst containing an stable Y-type zeolite and small amounts of rare-earth metal oxide, and an additive containing a shape-selective zeolite, in an FCC apparatus having a regeneration zone, a separation zone, and a stripping zone. Production of light-fraction olefins is maximized by applying appropriate process control, monitoring, and optimizing systems. Mathematical process models, including neural networks, statistical models and finite impulse models are used in conjunction with advanced controllers and optimizing routines to calculate optimal settings for various parameters. Process model and historical data to test a predictive system can provide early warning of potential performance degradation and equipment failure in the FCC unit, decreasing overall operating costs and increasing plant safety. | 2 |
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application claims priority from U.S. Patent Application No. 61/347,201 filed May 21, 2010.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH
[0002] Not Applicable.
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] This invention relates to novel hop acid compounds that provide improved flavor, foam, and antimicrobial contributions in malt beverages such as beer and active ingredients for health supplements. In particular, the invention relates to methods for preparing a hop acid mixture having an enantiomeric excess of a (+)-tetrahydro-α-acid, methods for preparing (+)-tetrahydro-α-acids that can be isomerized to (+)-trans-tetrahydro-iso-α-acids and (−)-cis-tetrahydro-iso-α-acids, and reduced to (+)-trans-hexahydroiso-α-acids and (−)-cis-hexahydroiso-α-acids and malt beverage bittering agents including the (+)-trans-tetrahydro-iso-α-acids, (−)-cis-tetrahydro-iso-α-acids, (+)-trans-hexahydroiso-α-acids, (−)-cis-hexahydroiso-α-acids, or mixtures thereof.
[0005] 2. Description of the Related Art
[0006] Chiral recognition of substances, i.e. the ability to distinguish a molecular structure from its mirror image, is one of the most important and widespread principles of biological activity. The first molecular event in odor perception is the interaction of an odorant with a receptor. As olfactory receptors have been identified as proteins, i.e. chiral molecules, this interaction should also be enantioselective, meaning that odor receptors should react differently with the two enantiomeric forms of a chiral odorant, leading to differences in odor strength and/or quality. Discrepant enantiomer effects are well-established, with numerous examples in taste perception. For example, limonene is present in both orange and lemon peels and responsible for their different odor characteristics because orange contains the right-handed (+) molecule while lemon contains the left-handed (−) molecule; (S)-(+)-carvone is a molecule with caraway-like odor while its mirror image molecule (R)-(−)-carvone has a spearmint odor. Linalool is one of main key hop flavor components in beer, which optical isomers have great impact on the character of hoppy flavor. (−)-Linalool is perceived with woody, lavender-like aroma, while its mirror image molecule, (+)-linalool, has sweet and citrus-like aroma.
[0007] Tetrahydroiso-α-acids (including three major analogs of tetrahydroisocohumulone, tetrahydrohumulone, and tetrahydroadhumulone) have shown more benefits in brewing than their analogous of iso-α-acids, ρ-iso-α-acids, and hexahydroiso-α-acids. Tetrahydroiso-α-acids impart the most bitter intensity, provide more light stability and flavor stability, enhance more foam, and exhibit stronger antimicrobial activity than the other hop bittering compounds in beer. Tetrahydroiso-α-acids are prepared from either α-acids (including three major analogs of cohumulone, n-humulone, and adhumulone) or β-acids (including three major analogs of colupulone, n-lupulone, and adlupulone) (See, P. Ting & H. Goldstein, J. Am. Soc. Brew. Chem. 54(2):103-109, 1996). From the α-acids (humulones), sequential hydrogenation and isomerization reactions or reversed isomerization and hydrogenation reactions of α-acids are involved as shown in FIG. 1 , wherein R═CH 2 CH(CH 3 ) 2 for n-humulone, R═CH(CH 3 ) 2 for cohumulone, and R═CH(CH 3 )CH 2 CH 3 for adhumulone. From the β-acids (lupulones), multiple reactions are involved including a sequential hydrogenolysis/hydrogenation reaction of β-acids, oxidation reaction of the hydrogenated desoxy-α-acids and then an isomerization reaction of tetrahydro-α-acids as shown in FIG. 1 , wherein R═CH 2 CH(CH 3 ) 2 for n-lupulone, R═CH(CH 3 ) 2 for colupulone, and R═CH(CH 3 )CH 2 CH 3 for adlupulone.
[0008] Both methods produce identical molecules of tetrahydroiso-α-acids, but only different from their stereoisomers. Tetrahydroiso-α-acids prepared from α-acids are optically active compounds, or enantiomers, due to the natural structure of α-acids (asymmetry molecules) (see, D. De Keukeleire and M. Verzele, J. Inst. Brewing, 76:265, 1970). However, tetrahydroiso-α-acids prepared from β-acids (no asymmetry molecules) are a racemic mixture (containing pairs of mirror image molecules or equal opposite enantiomers) with no optical activity (see, Patrick L. Ting and Henry Goldstein, J. Am. Soc. Brew. Chem. 54(2):103-109, 1996).
[0009] The molecular perception of stereochemistry of tetrahydroiso-α-acids and hexahydroiso-α-acids prepared from either α-acids or β-acids is very important because of their potential flavor, foam, antimicrobial contributions in beer as well as important ingredients for nutraceuticals and functional food (see U.S. Pat. No. 7,270,835). However, the stereochemistry and physiological properties (chiral recognition) have not been investigated and reported for tetrahydroiso-α-acids prepared from β-acids.
[0010] Therefore, there still exists a need for tetrahydroiso-α-acid compounds that improve flavor, foam, and antimicrobial contributions in malt beverages such as beer.
SUMMARY OF THE INVENTION
[0011] In one aspect, the invention provides a method for preparing a hop acid mixture having an enantiomeric excess of a (+)-tetrahydro-α-acid. In the method, a racemate of a tetrahydro-α-acid is contacted with an amine to form a precipitate having an enantiomeric excess of the (+)-tetrahydro-α-acid. The precipitate can be treated to prepare a solid having an enantiomeric excess of the (+)-tetrahydro-α-acid of greater than 50%, or more preferably greater than 80%. The amine can be a chiral amine such as (1S,2R)-(−)-cis-1-amino-2-indanol. The racemate of the tetrahydro-α-acid can be prepared by hydrogenating a β-acid to prepare a desoxy-α-acid, and oxidizing and isomerizing the hydrogenated desoxy-α-acid to prepare the racemate of the tetrahydro-α-acid. In one version of the method, the β-acid is colupulone, and the desoxy-α-acid is tetrahydrodesoxycohumulone. The tetrahydro-α-acid can be selected from tetrahydrohumulone, tetrahydrocohumulone, and tetrahydroadhumulone. In one version of the method, the precipitate is separated from a filtrate, and the precipitate is treated such that the precipitate has an enantiomeric excess of the (+)-tetrahydro-α-acid of greater than 80%, and the filtrate is treated such that a solid recovered from the filtrate has an enantiomeric excess of a (−)-tetrahydro-α-acid of greater than 80%. A reversed solid-liquid process is possible using a different amine.
[0012] In another aspect, the invention provides a method for preparing a hop acid. In the method, a racemate of a tetrahydro-α-acid is contacted with an amine to form a precipitate comprising a (+)-tetrahydro-α-acid; and the (+)-tetrahydro-α-acid is isomerized to a hop acid selected from the group consisting of (+)-trans-tetrahydro-iso-α-acids, (−)-cis-tetrahydro-iso-α-acids, and mixtures thereof. The (+)-trans-tetrahydro-iso-α-acid can be selected from (+)-trans-tetrahydro-iso-humulone, (+)-trans-tetrahydro-iso-cohumulone, and (+)-trans-tetrahydro-iso-adhumulone, and the (−)-cis-tetrahydro-iso-α-acid can be selected from (−)-cis-tetrahydro-iso-humulone, (−)-cis-tetrahydro-iso-cohumulone, and (−)-cis-tetrahydro-iso-adhumulone. The amine can be a chiral amine such as (1S,2R)-(−)-cis-1-amino-2-indanol. In one version of the method, the racemate of the tetrahydro-α-acid can be prepared by hydrogenating a β-acid to prepare a desoxy-α-acid, and oxidizing and isomerizing the hydrogenated desoxy-α-acid to prepare the racemate of the tetrahydro-α-acid.
[0013] In another aspect, the invention provides a method for preparing group of novel hop acids, (+)-tetrahydro-α-acids isomerized and reduced to a group selected from the group consisting of (+)-hexahydroiso-α-acids, (−)-hexahydroiso-α-acids, and mixtures thereof.
[0014] In yet another aspect, the invention provides an additive for flavoring a malt beverage, wherein the additive includes a bittering agent selected from the group consisting of (+)-trans-tetrahydro-iso-α-acids, a (−)-cis-tetrahydro-iso-α-acids, and mixtures thereof. The (+)-trans-tetrahydro-iso-α-acid can be selected from the group consisting of (+)-trans-tetrahydro-iso-humulone, (+)-trans-tetrahydro-iso-cohumulone, and (+)-trans-tetrahydro-iso-adhumulone, and the (−)-cis-tetrahydro-iso-α-acid can be selected from the group consisting of (−)-cis-tetrahydro-iso-humulone, (−)-cis-tetrahydro-iso-cohumulone, and (−)-cis-tetrahydro-iso-adhumulone.
[0015] In still another aspect, the invention provides novel ingredients for nutraceutical and functional foods, wherein the active ingredients includes a bittering agent selected from the group consisting of (+)-tetrahydro-α-acids, (+)-trans-tetrahydroiso-α-acids, (−)-cis-tetrahydroiso-α-acids, (+)-trans-hexahydroiso-α-acids, (−)-cis-hexahydroiso-α-acids, and mixtures thereof.
[0016] In yet another aspect, the invention provides a method for preparing a hop acid mixture. The method comprises contacting a racemate of tetrahydroiso-α-acids with a chiral amine to form a hop acid complex as a precipitate or in solution such that the hop acid complex has an enantiomeric excess of (+)-tetrahydroiso-α-acids. The enantiomeric excess of the resolved (+)-tetrahydroiso-α-acids can be greater than 50%, preferably greater than 60%, preferably greater than 70%, preferably greater than 80%, and preferably greater than 90%. The resolved tetrahydroiso-α-acids can be enantiomerically pure. The resolved (+)-tetrahydroiso-α-acids can be reduced to a hop acid selected from the group consisting of (+)-trans-hexahydro-iso-α-acids, (−)-cis-hexahydro-iso-α-acids, and mixtures thereof.
[0017] In still another aspect, the invention provides a method for preparing a hop acid mixture. The method comprises resolving a racemate of tetrahydroiso-α-acids with a chiral column chromatography to separate an enantiomeric excess of (+)-tetrahydroiso-α-acids. The enantiomeric excess of the resolved (+)-tetrahydroiso-α-acids can be greater than 50%, preferably greater than 60%, preferably greater than 70%, preferably greater than 80%, and preferably greater than 90%. The resolved tetrahydroiso-α-acids can be enantiomerically pure. The resolved (+)-tetrahydroiso-α-acids can be reduced to a hop acid selected from the group consisting of (+)-trans-hexahydro-iso-α-acids, (−)-cis-hexahydro-iso-α-acids, and mixtures thereof.
[0018] In yet another aspect, the invention provides an additive for flavoring a malt beverage wherein the additive comprises a bittering agent selected from the group consisting of (+)-trans-tetrahydroiso-α-acids, (−)-cis-tetrahydroiso-α-acids, (+)-trans-hexahydroiso-α-acids, (−)-cis-hexahydroiso-α-acids, and mixtures thereof. In still another aspect, the invention provides a malt beverage including the additive wherein the bittering agent is present in the malt beverage at a level of 1 ppm to 100 ppm.
[0019] In still another aspect, the invention provides an active ingredient for a health supplement wherein the ingredient comprises a hop acid selected from the group consisting of (+)-tetrahydro-α-acids, (+)-trans-tetrahydro-iso-α-acids, (−)-cis-tetrahydro-iso-α-acids, (+)-trans-hexahydro-iso-α-acids, (−)-cis-hexahydroiso-α-acids, and mixtures thereof.
[0020] These and other features, aspects, and advantages of the present invention will become better understood upon consideration of the following detailed description, drawings and appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1 shows a scheme of tetrahydroiso-α-acids preparation from either α-acids or β-acids.
[0022] FIG. 2 shows the analytical HPLC resolution of (±)-tetrahydrocohumulone by a 250×4.6 mm β-Cyclobond column with 75% CH 3 CN+25% of 1% acetic acid in 20% CH 3 OH/H 2 O) at 280 nm and 1.2 ml/min.
[0023] FIG. 3 is a diagram of the dynamic resolution of (±)-THCO.
[0024] FIG. 4 is a plot of circular dichroism of (±),(+), and (−)-THCO.
[0025] FIG. 5 shows the chiral HPLC separation of isomerized (+) and (−)-THCO (top) and two CD spectra of (+) vs. (−)-trans-THICO (bottom).
DETAILED DESCRIPTION OF THE INVENTION
[0026] In one example method of invention, dynamic resolution of a racemic tetrahydro-α-acid mixture has been achieved. Suitable solvents for the resolution can be selected such that at least some of the desired diastereomeric solid precipitates in the solvent and the other member of the pair remains dissolved in the solution. Non-limiting example solvents include substituted or unsubstituted aliphatic or alicyclic hydrocarbons. Some preferred solvents are hexane, cyclohexane and toluene. The solvents and the temperature of the dynamic resolution will vary with the particular hop acid subjected to the resolution.
[0027] Precipitation of the desired diastereomeric solid can be achieved with a chiral amine. A preferred amine is one that allows formation of a pair of diastereomeric solids, one member of the pair of diastereomers being at least partially insoluble in the solvent system of the process. A preferred amine is one that allows formation of a pair of diastereomers, one member of the pair being preferentially a precipitate under the reaction conditions. The precipitate can be crystalline or non-crystalline. The chiral amine can be, for example, (1S,2R)-(+)-cis-1-amino-2-indanol. Other chiral amines can be expected to be useful in effecting the resolution of the hop acid.
[0028] The less soluble diastereomeric salt from the reaction can be isolated, for example, by filtration, centrifugation, or decantation. For instance, the reaction mixture is cooled to room temperature and the resulting precipitate is recovered by filtration. The filter cake containing the product can be washed with a washing solvent such as an aliphatic hydrocarbon (e.g., hexane). Once isolated, the precipitated diastereomeric salt can be liberated from its complexed chiral amine by reaction with a suitably strong acid. Non-limiting example acids include sulfuric acid, phosphoric acid and hydrochloric acid. The diastereomeric compound that remains in solution in the filtrate can also be isolated with an acid.
[0029] Dynamic resolution of the racemate of a tetrahydro-α-acid or racemate of a tetrahydroiso-α-acid in accordance with the invention can produce an enantiomeric excess of the one of the resolved tetrahydro-α-acids or tetrahydroiso-α-acids of greater than 50%, preferably greater than 60%, preferably greater than 70%, preferably greater than 80%, and preferably greater than 90%. The resolved tetrahydro-α-acid or (+)-tetrahydroiso-α-acid can be enantiomerically pure. In one form, the resolved tetrahydro-α-acid is (+)-tetrahydrocohumulone.
[0030] The resolved tetrahydro-α-acids can be isomerized to tetrahydro-iso-α-acids by boiling in a suitable solvent such as an ethanol-water mixture, optionally in the presence of a catalyst such as a calcium or magnesium salt. Other isomerization techniques can be used. The tetrahydroiso-α-acid compounds can provide improved flavor, foam, and antimicrobial contributions when added to malt beverages such as beer. In one form, the tetrahydro-iso-α-acid is (+)-trans-tetrahydro-iso-cohumulone or (−)-cis-tetrahydro-iso-cohumulone. The resolved tetrahydro-α-acids can be reduced to (+)-trans-hexahydroiso-a-acids and (−)-cis-hexahydroiso-a-acids.
[0031] A variety of optical isomers have been described as having different odor qualities and/or different odor intensities. Such considerations prompted the following experimental study, which aimed to resolve gram quantities of each enantiomer of (±)-tetrahydrocohumulone and to assess their isomerized enantiomers for bitterness, foam quality, and antimicrobial activity. The following Examples are presented for purposes of illustration and not of limitation.
Examples
HPLC of (±)-tetrahydrocohumulone (THCO) and (+/−) and (−/+)-cis/trans-tetrahydroisocohumulones (THICO)
[0032] A 5 μm 250×4.6 mm Cyclobond I 2000 column (Advanced Separation Technologies Inc.) was used. To resolve (±)-THCO, an isocratic mixture of 25% A (CH 3 CN) and 75% B (1% acetic acid+20% methanol/H 2 O) was used as the mobile phase at a flow rate 1.2 mL/min and detection at 280 nm. Two enantiomers, (−) and (+)-THCO, were eluted, respectively in FIG. 2 . (−)-THCO was identified by the hydrogenated α-acids standard. To resolve (±)-cis and (±)-trans-THICO, an isocratic mixture of 35% A (CH 3 CN) and 65% B (0.01M sodium citrate+20% methanol/H 2 O) was used as the mobile phase at a flow rate 1.2 mL/min and detection at 254 nm. The elution order was (−)-trans, (+)-trans, (−)-cis, and (+)-cis-THICO identified by the retention times of (+)-cis-THICO and (−)-trans-THICO standards as shown in FIG. 5 .
Preparation of Tetrahydrodesoxycohumulone
[0033] To a solution of 50 g hexane-crystallized colupulone (0.125 moles) in 250 mL of ethanol was added 10 mL of concentrated sulfuric acid and 5 g of 5% Pd/C catalyst. The mixture was stirred and hydrogenated under 10 psig hydrogen gas in an autoclave. The hydrogenation reaction was completed after 30 min. at 35-50° C. The vessel was purged with nitrogen and the mixture was filtered to give a clear yellow solution of tetrahydrodesoxycohumulone, used directly in the next step.
Oxidation with Peracetic Acid of Tetrahydrodesoxycohumulone to (±)-tetrahydrocohumulone (THCO)
[0034] To the above solution was added 23.75 g of 40% peracetic acid (0.125 moles) slowly in a three-neck round bottom flask which was equipped with a thermometer, a condenser, and additional funnel. After addition, the reaction was heated to 50-60° C. for 1 hour and allowed to cool to room temperature. About 100 mL tap water was added and stirred for 1 hour. The ethanol was recovered under vacuum and 200 mL hexane was added to solubilize the THCO in aqueous solution. After a phase separation, the hexane solution was washed with tap water twice to afford 35 g of THCO.
Resolution of (±)-tetrahydrocohumulone (THCO)
[0035] To a solution of 11 g of (±)-tetrahydrocohumulone (THCO) (0.031 moles), 20 mL toluene and 300 mL cyclohexane was added 5.5 g of (1S,2R)-(−)-cis-1-amino-2-indanol (Al) (0.037 moles) in 50 mL cyclohexane. The solution was boiled for 15 min. and allowed to cool at room temperature. A yellow solid was crystallized and filtered from the solution. The yellow solid was mixed with 100 mL hexane and 100 mL of 2N HCl. The hexane phase was washed three times with water. After drying with anhydrous magnesium sulfate, the solvent was removed under vacuum to yield 4.65 g of (+)-THCO and confirmed by a chiral HPLC (β-Cyclobond column) with 90% enantiomeric excess (e.e.). The filtrate was acidified with 100 mL of 2N HCl and washed with water three times. After drying with anhydrous magnesium sulfate, the solvent was removed by vacuum to afford 5.3 g of 86% e.e. (−)-THCO and confirmed by β-Cyclobond HPLC.
Isomerization of (+), (−), and (±)-tetrahydrocohumulone (THCO) to cis/trans-tetrahydroisocohumulone
[0036] To 2.5 g of THCO (7.1 mmoles) and 50 mL ethanol was stirred and heated with 0.3 g NaOH and 43 mg of magnesium sulfate. The isomerization reaction was refluxed for 2 hours and allowed to cool at room temperature. The resulted solution was acidified by 2N HCl and ethanol was recovered by vacuum. The resulted oil was extracted by 50 mL hexane and two phases were separated. The hexane phase was dried by anhydrous magnesium sulfate and the solvent was removed by vacuum to yield enantiomers and a racemate of cis/trans-tetrahydroisocohumulone (THICO).
CONCLUSION
[0037] (1S,2R)-(−)-cis-1-Amino-2-indano is an unequivocal chiral reagent for resolving racemic hop acids. It reacts with (±)-tetrahydrocohumulones to selectively produce a crystal form of (+)-tetrahydrocohumulone (THCO)/(1S,2R)-(−)-cis-1-amino-2-indano from the solution of (−)-THCO and (1S,2R)-(−)-cis-1-amino-2-indano. It is a dynamic process that can easily process several grams of (±)-tetrahydro-α-acids for any application. The (+)-THCO is a novel bittering precursor as well as its derivatives of (−)-cis/(+)-trans-tetrahydroisocohumulone (THICO). On the other hand, its counterpart, (−)-THCO, is identical to the hydrogenated (−)-cohumulone (a nature α-acid). Three THICO molecules can be enantioselectively distinguished by our receptors, leading to different odor intensities and odor qualities. THICO II from its (+)-THCO have the most bitterness and longest lingering and (±)-THICO III have milder and smooth bitterness than THICO I from (−)-THICO. The foam situation is more complicated by findings of enantioselective effects of each chiral isomer with damaged conformation of LTP (a foam protein) during the kettle boiling. Three THICO I, II, and III molecules demonstrate the same antibacterial effectiveness using the minimum inhibitory concentration (MIC) and the bacterial zone of inhibition (BZI) tests on Pediococcus damnosus and Lactobacillus brevis . It clearly indicates that the enantioselectively antibacterial interactions between THICO I, II, III and the microbial do not occur.
Results and Discussion
[0038] The molecular perception of stereochemistry of tetrahydroiso-α-acids prepared from either α-acids or β-acids is very important because of their potential flavor, foam, antimicrobial contributions in beer. Verzele and De Keukeleire (D. De Keukeleire and M. Verzele, J. Inst. Brewing, 76:265, 1970; “Chemistry and analysis of Hop and Beer Bitter Acids”, M. Verzele and D. De Keukeleire, Elsevier, 1991) have established the R-configuration and (−)-optical rotation of α-acids with an asymmetric center at C-6 and also determined the optical properties of their isomerized derivatives denoted as (+)-cis-iso-α-acids and (−)-trans-iso-α-acids. The hydrogenation of either α-acids or isomerized-α-acids retains the chirality, in other words, no optical property is changed. On the other hand, the β-acids prepared tetrahydroiso-α-acids are a racemic mixture consisting of two pairs of (+/−)-cis/trans- and (−/+)-cis/trans-isomers from the isomerization of a racemic mixture of (±)-tetrahydro-α-acids. Because the β-acids are dissymmetric or achiral compounds, the hydrogenolysis/hydrogenation of β-acids produce planar molecules, tetrahydro desoxy-α-acids with a C2 symmetry. At the oxidation step, a chiral center at C-6 is introduced to generate a pair of (±)-tetrahydro-α-acids as shown in FIG. 1 .
Resolution by Liquid Chromatography
[0039] Ting and Goldstein confirmed the optical rotations of the hydrogenated iso-α-acids as (+)-cis- and (−)-trans-tetrahydroiso-α-acids. (Patrick L. Ting and Henry Goldstein, J. Am. Soc. Brew. Chem. 54(2):103-109, 1996), while a zero value of optical rotations of (±)-cis- and (±)-trans-tetrahydroiso-α-acids is obtained from the β-acids preparation. Ting and Goldstein successfully resolved and assigned (±)-tetrahydro-α-acids using a combination of a semi-preparative C-18 column and an analytical Cyclobond HPLC column (β-Cyclodextrin bonded on 5μ silica gel, a chiral phase column). The column was also used to resolve most of (+) and (−)-enantiomers and diastereomers of total (±)-tetrahydroiso-α-acids.
[0040] To evaluate the properties of each enantiomer of tetrahydroiso-α-acids in beer, a gram quantity of substances is needed. Due to the complex compositions of hop bittering compounds (containing at least of 12 compounds with 3 major analogs and 2 diastereoisomers and 2 enantiomers), a strategy of simplifying the resolution process is starting with colupulone, one component of β-acids, to produce (±)-tetrahydrocohumulone. Resolution of (±)-tetrahydrocohumulone (THCO), bittering precursors, should be less complicated than their isomerized (±)-cis- and (±)-trans-tetrahydroisocohumulones (THICO).
[0041] An analytical chiral HPLC (high pressure liquid chromatography) column (β-Cyclobond) was used to analyze and identify the resolved compounds as shown in FIG. 2 . In FIG. 2 , (±)-THCO is well-resolved into (−)-THCO identified by authentic (−)-tetrahydro-α-acids and eluted before (+)-THCO. Since a chiral liquid chromatography (LC) was a prevalent technique of resolving enantiomers, two β-Cyclobond 10×2″ and 20×2″ columns simulated to the analytical conditions were used to separate the racemic mixture of (±)-THCO at milligrams to gram quantities. The resolution of (±)-THCO was poor and ineffective.
Resolution by Dynamic Crystallization
[0042] Alternatively, using an (−)-alkaloid, (1S,2R)-(−)-cis-1-amino-2-indanol (Al) to react with (±)-THCO becomes a dynamic resolution technique (Chemical & Engineering News, Sep. 9, 2002). Two diastereomeric salts were formed; one, (+)-THCO/(−)-alkaloid, was crystallized out and left one, (−)-THCO/(−)-alkaloid in the solution as shown in FIG. 3 . After acidification, it regenerated high optically pure (+) and (−)-THCO, separately, as well as more than gram quantities yield sufficient to perform various tests. A chiral HPLC and CD (Circular Dichroism) confirmed the optical purity and optical spectrum of resolved (+) and (−)-THCO vs. (±)-THCO ( FIG. 4 ). The identity of (−)-THCO were confirmed by comparison of the retention time of chiral HPLC and CD spectrum with the hydrogenated α-acids. The (+)-THCO is a novel bittering precursor having an opposite CD spectrum as (−)-THCO which is a hydrogenated natural α-acid. The isomerization of (+)-THCO produced two novel (−)-cis/(+)-trans-tetrahydroisocohumulone (THICO) in opposite to (−)-THCO produced (+)-cis/(−)-trans-THICO identical to the hydrogenated natural iso-α-acids. FIG. 5 shows a chiral HPLC separation/resolution of (+/−) and (−/+)-cis- and trans-THICO and two CD spectra of (+)- and (−)-trans-THICO. The bitter perception, foam quality, and antimicrobial activity of three molecules and their derivatives of (+/−)-cis/trans-THICO (THICO I), (−/+)-cis/trans-THICO (THICO II), and (±)-cis/trans-THICO (THICO III) were investigated, respectively.
Bitterness Perception
[0043] An aqueous 5% v/v ethanol/H 2 O solution was spiked with 6 ppm of THICO I, II, and III. The bitterness of three molecular perceptions is summarized in Table 1. It indicates that the bitterness intensity is II>III>I and the bitter perception of III is smooth and milder than the others.
[0000]
TABLE 1
Bitterness of three THICO I, II, and III in 5% ethanol/H 2 O
THICO I (natural)
THICO II (novel)
THICO III (racemic)
Less bitter at back of
Most bitter and
Stronger than I, but similar,
tongue, harsh, slight
lingering,
smooth, milder, clean
lingering
astringent, bitter in
bitterness
whole mouth
[0044] Two sets of unhopped lagers (A and B) were spiked with 6 ppm and 13 ppm of THICO I, II, and III, respectively. A C-18 reversed phase HPLC analysis of cis/trans-THICO present in each beer is shown in Table 2.
[0000]
TABLE 2
HPLC analysis of cis/trans-tetrahydroisocohumulones (THICO) in Beer
THICO I (ppm)
THICO II (ppm)
THICO III (ppm)
A
5.6
6.0
6.0
B
13.7
12.2
13.8
[0045] Sensory evaluation indicated that beer with THCO II was noted as having the strongest initial bitterness and lingered the longest. The other two beers were noted as being similar with the THICO I having a little more initial bitterness and the bitterness in the THICO III beer diminished quickly. In set B, THICO II beer had a strong initial bitterness that increased (described as late bitterness) and also lingered. The other two beers were noted as being similar with initial intense bitterness that diminished slowly with slight lingering bitterness. It indicates that our odor receptors can differentiate two enantiomeric THICO I and II, leading to differences in bitter strength and quality.
Foam
[0046] One major factor of beer foam is an interaction of a lipid transfer protein (LTP) from barley with the hop bittering compounds. (see, L. Lusk, H. Goldstein, D. Ryder, J. Amer. Soc. Brew. Chem. 53(3):93-103, 1995). Tetrahydroiso-α-acids interact preferentially with LTP due to their greater hydrophobicity. (see, K. Takeshi and T. Shellhammer, J. Agric. Food Chem., 2008, 56 (18), pp 8629-8634). The Nibem and half-life foam test of three bittering molecules in beers in set A do not show any significant differences (see Table 3). Discrepancy of the enantioselective effects between enantiomers of THICO and LPT is not clear in the beer foam formation. It might be due to disruption of the conformation of LPT which has been known to be damaged after long kettle boiling (Sandra N. E. Van Nierop, David E. Evans, Barry C. Axcell, Ian C. Cantrell, and Marina Rautenbach, J. Agric. Food Chem., 2004, 52 (10), pp 3120-3129; E. N. Clare Mill, Chunli Gao, Peter J. Wilde, Neil M. Rigby, Ramani Wijesinha-Bettonis, Victoria E. Johnson, Lorna J. Smith and Alan R. Mackie, Biochemistry, 2009, 48 (51), pp 1208-12088).
[0000]
TABLE 3
Results of beer foam and bittering molecules
Nibem 30 sec.
Half-Life
THICO I
255
4.7
THICO II
259
5.0
THICO III
246
5.3
Antimicrobial Activity of THICO I, II, III and Minimum Inhibitory Concentration (MIC) and Bacterial Zone of Inhibition (BZI)
[0047] The antimicrobial effect of three molecules was tested on Pediococcus damnosus and Lactobacillus brevis with two methods (MIC and BZI). MIC was determined based on the concentration at which no bacteria were detected in the modified BMB without Tween 80 culture medium. The result is summarized in Table 4 and the MIC is 16 ppm for both THICO I and II. The average diameters of the zones of bacterial inhibition in Universal Beer Agar (UBA) produced by the filter paper disks immersed in 4000 ppm of THICO I, II, and III in 70% ethanol/water are shown in Table 5. Zone diameters increased with the same rates for three molecules on two different organisms ( Pediococcus damnosus and Lactobacillus brevis ) indicate that all molecules have the same antibacterial effectiveness. No enantioselective antibacterial interactions between THICO I, II, III and the microbial occur.
[0000]
TABLE 4
Minimum inhibitory concentration of THICO I and II
Pediococcus damnosus
Minimum Inhibitory Concentration of Hop Acids in 70% Ethanol
ppm
128
64
32
16
8
4
2
1
0.5
0
THICO I
−
−
−
+/−
+
+
+
+
+
+
THICO II
−
−
−
+/−
+
+
+
+
+
+
+ = Growth of beer spoilage bacteria
− = No growth of beer spoilage bacteria
+/− = Partial inhibition of bacterial growth
[0000]
TABLE 5
Antimicrobial effect of THICO I, II, and III on bacterial
Diameter of Bacterial Zone of Inhibition (mm)
Pediococcus damnosus
Lactobacillus brevis
Control
0
0
THICO I
11.5
26
THICO II
12
26.5
THICO III
12
22.5
[0048] Thus, in the present invention, resolution of a racemic (±)-tetrahydrocohumulone (or tetrahydro-α-acid) and their isomerized tetrahydroisocohumulones (or tetrahydroiso-α-acid) has been achieved in gram quantity by a dynamic crystallization with (1S,2R)-(−)-1-amino-2-indanol. The resolved (+)-tetrahydrocohumulone (THCO) is a novel bittering precursor while the (−)-THCO is identical to the hydrogenated (−)-cohumulone (a natural α-acid). Both enantiomers are isomerized to the same molecular structures, but with opposite optical rotations. The (+)-THCO is converted into two novel bittering diastereomers, (−)-cis- and (+)-trans-tetrahydro isocohumulone (THICO II) while (−)-THCO is converted into (+)-cis- and (−)-trans-THICO (THICO I) identical to the hydrogenated cis and trans-isocohumulone (a natural iso-α-acid).
[0049] Sensory indicates that the bitter intensity of three molecules is THICO II>(±)-THICO III>THICO I. The perception of (±)-THICO III is smooth, clean and milder than I and II. In the foam situation, it seems no apparent foam quality differences among three molecular beers. In other words, no clear discrepancy of enantioselective effects among three molecules and lipid transfer protein (LTP) is found. It may be due to destruction of LTP conformation during long kettle boiling.
[0050] The minimum inhibitory concentration (MIC) of THICO I and II is similar at 16 ppm against Pediococcus damnosus . Zone diameters increased with the same rates for three THICO I, II, and III molecules on two different organisms ( Pediococcus damnosus and Lactobacillus brevis ) indicate that all exhibit the same antibacterial effectiveness or no enantioselective antibacterial effect among THICO I, II, III and the microbial.
[0051] Although the invention has been described in considerable detail with reference to certain embodiments, one skilled in the art will appreciate that the present invention can be practiced by other than the described embodiments, which have been presented for purposes of illustration and not of limitation. Therefore, the scope of the appended claims should not be limited to the description of the embodiments contained herein. | A method for preparing a hop acid mixture having an enantiomeric excess of a (+)-tetrahydro-α-acid is disclosed. In the method, a racemate of a tetrahydro-α-acid is contacted with an amine to form a precipitate having an enantiomeric excess of the (+)-tetrahydro-α-acid. A method for preparing a hop acid is also disclosed. In the method, a racemate of a tetrahydro-α-acid is contacted with an amine to form a precipitate comprising a (+)-tetrahydro-α-acid, and the (+)-tetrahydro-α-acid is isomerized to a hop acid selected from the group consisting of (+)-trans-tetrahydro-iso-α-acids, (−)-cis-tetrahydro-iso-α-acids, and mixtures thereof, and reduced to (+)-trans-hexahydroiso-α-acids and (−)-cis-hexahydroiso-α-acids. An additive for flavoring a malt beverage is also disclosed. The additive includes a bittering agent selected from the group consisting of (+)-trans-tetrahydro-iso-α-acids, (−)-cis-tetrahydro-iso-α-acids, (+)-trans-hexahydroiso-α-acids, (−)-cis-hexahydroiso-α-acids, and mixtures thereof. | 2 |
CROSS REFERENCE TO RELATED APPLICATION
This is a Continuation of U.S. Ser. No. 07/911,662, filed Jul. 16, 1992, now abandoned; which is a Continuation-in-Part of U.S. Ser. No. 07/736,888 filed Jul. 29, 1991, now abandoned.
BACKGROUND OF THE INVENTION
The present invention is directed to a new method of treating cognitive deficiencies such as memory loss, Alzheimer's disease, and other dementias using dihydroquinazoline derivatives as the active ingredients.
Tetrahydroacridine derivatives have been reported to possess acetylcholinesterase inhibiting activity, which properties have been found useful in the treatment of cognitive deficit states. For example, tacrine, 9-amino-1,2,3,4-tetrahydroaminoacridine, has proved effective in the alleviation of symptoms of Alzheimer's disease. Dependent on the dosing sequence for effective results, use of tetrahydroaminoacridines may cause liver toxicity. Tetrahydroaminoacridines are also known to be mutagenic.
It has now been found that certain quinazoline derivatives also possess cholinesterase inhibiting activity and are thus useful for treating cognitive deficiencies such as: Alzheimer's disease, senile dementias, multiple infarct dementias, and other conditions where memory and cognitive function improvement or stabilization is desired. The present quinazoline derivatives may also be useful in eliminating symptoms of tardive dyskinesia, e.g., induced by tricyclic antidepressants, Huntington's chorea, and the side effects caused by centrally acting anticholinergics, e.g., tricyclic antidepressants, scopolamine, quinuclidinyl benzilate and the like. The above compounds would also be useful in the treatment of manic depressive disorder.
It is believed that the present quinazoline derivatives lacking the aromatic amine moiety of the tetrahydroaminoacridines will not possess the toxicity of the tetrahydroaminoacridines.
SUMMARY OF THE INVENTION
Accordingly the present invention comprises a method of treating cognitive deficiencies comprising administering to a host in need thereof a therapeutically effective amount in unit dosage form of a compound of the formula ##STR4## wherein A is absent or represents ##STR5## in which n is 1-10, P is a bond or (CH 2 ) m in which m is 0-10, wherein a nitrogen, oxygen, or sulfur atom may replace a methylene group in ring A and attached to a carbon atom in ring A is Y, in which Y is hydrogen, hydroxy, carboxy, lower alkoxy, lower alkyl, aryl, heteroaryl, keto, lower alkoxycarbonyl, lower alkanoyl, or oxime thereof;
M is ═O, ═S, ═NR, ##STR6## or ═CRR', in which R and R' are each independently hydrogen, lower alkyl, hydroxy, lower alkenyl, lower alkoxy, lower alkynyl, aryl, aryloxy, aryl lower alkyl, heteroaryl, or heteroaryllower alkyl and, when taken together, may form a three- to six-membered ring optionally containing one to three heteroatoms selected from nitrogen, oxygen, and sulfur; and
X is absent or one to four substituents selected from hydrogen, halogen, alkyl(C 1-22 ), straight or branched, saturated or alkenyl or alkynyl, if alkyl of appropriate size can form a ring, saturated or unsaturated, containing (or not containing) one or more heteroatoms, such as O, S, N, Se, P, and the like, or an aromatic or heteroaromatic ring containing (or not containing) one or more heteroatoms, such as O, S, N, Se, and the like, primary, secondary, or tertiary amino, nitro, lower alkylthio, or aryl (or heteroaryl)thio, mercapto, hydroxy, carboxy, lower alkoxy, or aryl (or heteroaryl)oxy, alkyl(C 1-22 ), or aryl (or heteroaryl)sulfinyl, alkyl(C 1-22 ), or aryl (or heteroaryl)sulfonyl, perfluoroalkyl(C 1-22 ), such as trifluoromethyl, perfluoroalkoxy(C 1-22 ), such as trifluoromethoxy, perfluoroalkylthio(C 1-22 ), such as trifluoromethylthio, perfluoroalkylsulfinyl(C 1-22 ), such as trifluoromethylsulfinyl, perfluoroalkylsulfonyl(C 1-22 ), such as trifluoromethylsulfonyl, alkyl(C 1-22 ), or aryl (or heteroaryl)carbamoyl, or diacylamino, including cyclic imido, such as succinimido, alkyl(C 1-22 ), or aryl (or heteroaryl)sulfinylamido, alkyl(C 1-22 ), or aryl (or heteroaryl)sulfonylamido, perfluoroalkyl(C 1-22 )sulfinylamido, such as trifluoromethylsulfinylamido, perfluoroalkyl(C 1-22 )sulfonylamido, such as trifluoromethylsulfonylamido above, trialkylsilyl, such as trimethylsilyl, or triethylsilyl, acyl, such as acetyl, benzoyl, phenylacetyl, hydrocinnamoyl, and the like, perfluoroacyl, such as trifluoroacetyl, heptafluorobutyryl, and the like, acyl-lower alkyl, such as acetylmethyl, benzoylmethyl, phenylacetylmethyl, hydrocinnamoylmethyl, and the like, perfluoroacyl-lower alkyl, such as trifluoroacetylmethyl, heptafluorobutyrylmethyl, and the like, alkyl(C 1-22 ), or aryl (or heteroaryl)carbamoyloxy, dialkyl(C 1-22 ), or diaryl (or diheteroaryl)carbamoyloxy, alkyl(C 1-22 ), or aryl (or heteroaryl)carbamoylthio, alkyl(C 1-22 ), or aryl (or heteroaryl)carbamoylalkyl, or diacylaminoalkyl, including cyclic imidoalkyl, such as acetamidomethyl, octanamidomethyl, or succinimidomethyl, aryl, or aryl lower alkyl including substituted aryl with groups such as halogen and groups described above, heteroaryl or heteroaryllower alkyl, such as furan, thiophene, pyrrole, pyridine and the like, including substituted derivatives with groups such as halogen and groups described above;
Z is hydrogen, halogen, alkyl (C 1-12 ), straight or branched, saturated or alkenyl or alkynyl if alkyl of appropriate size can form a ring, saturated or unsaturated, containing or not containing one or more heteroatoms, selected from O, S, and N, can also form an aromatic or heteroaromatic ring containing or not containing one or more heteroatoms, selected from O, S, and N, primary, secondary, or tertiary amino-lower alkylthio-, aryl-, heteroarylthio, mercapto, hydroxy, carboxy, carbalkoxy in which alkyl is C 1 -C 22 , lower alkoxy, aryl, or heteroaryloxy, perfluoroalkyl in which alkyl is C 1 -C 22 , perfluoroalkoxy in which alkyl portion is C 1 -C 22 ), alkyl (C 1-22 ), aryl or heteroarylcarbamoyl, diacylamino, cyclic imido, or acyl, or a pharmaceutically acceptable acid addition salt thereof, with the proviso that when A is ##STR7## in which n is 1, m is 0, Y is hydrogen, and M is RR' where R and R' are both hydrogen, X is not absent nor a single methoxy or hydroxy group.
The present invention also includes novel compounds of the formula ##STR8## wherein A represents ##STR9## in which n is 1-10, P is a bond or (CH 2 ) m in which m is 0-10, wherein a nitrogen, oxygen, or sulfur atom may replace a methylene group in ring A, which is not adjacent to the quinazoline moiety, and attached to a carbon atom in ring A is Y, in which Y is hydrogen, hydroxy, halogen, carboxy, lower alkoxy, lower alkyl, aryl, heteroaryl, keto, lower alkoxy carbonyl or lower alkanoyl;
M is ═S, ═NR, ##STR10## in which R and R' are independently hydrogen, hydroxy, lower alkyl, lower alkoxy, lower alkenyl, lower alkynyl, aryl, aryloxy, aryllower alkyl, heteroaryl or heteroaryllower alkyl and, when taken together, may form a three- to six-membered ring optionally containing one to three heteroatoms selected from nitrogen, oxygen, and sulfur; and
X is absent or one to four substituents selected from halogen, alkyl (C 1-22 ), straight or branched, saturated or alkenyl or alkynyl, if alkyl of appropriate size can form a ring, saturated or unsaturated, containing (or not containing) one or more heteroatoms, such as O, S, N, Se, P, and the like, or an aromatic or heteroaromatic ring containing (or not containing) one or more heteroatoms, such as O, S, N, Se, and the like, primary, secondary, or tertiary amino nitro-lower alkylthio, or aryl (or heteroaryl)thio, mercapto, hydroxy, carboxy, lower alkoxy, or aryl (or heteroaryl)oxy, alkyl(C 1-22 ) or aryl (or heteroaryl)sulfinyl, alkyl(C 1-22 ), or aryl (or heteroaryl)sulfonyl, perfluoroalkyl(C 1-22 ), such as trifluoromethyl, perfluoroalkoxy(C 1-22 ), such as trifluoromethoxy, perfluoroalkylthio(C 1-22 ), such as trifluoromethylthio, perfluoroalkylsulfinyl(C 1-22 ), such as trifluoromethylsulfinyl, perfluoroalkylsulfonyl(C 1-22 ), such as trifluoromethylsulfonyl, alkyl(C 1-22 ), or aryl (or heteroaryl)carbamoyl, or diacylamino, including cyclic imido, such as succinimido, alkyl(C 1-22 ), or aryl (or heteroaryl)sulfinylamido, alkyl(C 1-22 ), or aryl (or heteroaryl)sulfonylamido, perfluoroalkyl(C 1-22 )sulfinylamido, such as trifluoromethylsulfinylamido, perfluoroalkyl(C 1-22 )sulfonylamido, such as trifluoromethylsulfonylamido above, trialkylsilyl, such as trimethylsilyl, or triethylsilyl, acyl, such as acetyl, benzoyl, phenylacetyl, hydrocinnamoyl, and the like, perfluoroacyl, such as trifluoroacetyl, heptafluorobutyryl, and the like, acyl-lower alkyl, such as acetylmethyl, benzoylmethyl, phenylacetylmethyl, hydrocinnamoylmethyl, and the like, perfluoroacyl-lower alkyl, such as trifluoroacetylmethyl, heptafluorobutyrylmethyl, and the like, alkyl(C 1-22 ), or aryl (or heteroaryl)carbamoyloxy, dialkyl(C 1-22 ), or diaryl (or diheteroaryl)carbamoyloxy, alkyl(C 1-22 ), or aryl (or heteroaryl)carbamoylthio, alkyl(C 1-22 ), or aryl (or heteroaryl)carbamoylalkyl, or diacylaminoalkyl, including cyclic imidoalkyl, such as acetamidomethyl, octanamidomethyl, or succinimidomethyl, aryl or aryl lower alkyl, including substituted aryl with groups such as halogen and groups described, heteroaryl or heteroaryllower alkyl, such as furan, thiophene, pyrrole, pyridine and the like, including substituted derivatives with groups such as halogen and groups described above;
Z is hydrogen, halogen, alkyl(C 1-12 ), straight or branched, saturated or alkenyl or alkynyl if alkyl of appropriate size can form a ring, saturated or unsaturated, containing or not containing one or more heteroatoms, selected from O, S, and N, can also form an aromatic or heteroaromatic ring containing or not containing
one or more heteroatoms, selected from O, S, and N, primary, secondary, or tertiary aminolower alkylthio-, aryl-, heteroarylthio, mercapto, hydroxy, carboxy, carbalkoxy in which alkyl is C 1 -C 22 , lower alkoxy, aryl, or heteroaryloxy, perfluoroalkyl in which alkyl is C 1 -C 22 , perfluoroalkoxy in which alkyl portion is C 1 -C 22 ), alkyl(C 1-22 ), aryl or heteroarylcarbamoyl, diacylamino, cyclic imido, or acyl, or a pharmaceutically acceptable acid addition salt thereof; with the proviso that when A is ##STR11## in which n is 1-3, m is 0, Y is hydrogen, and M is RR' where R and R' are both hydrogen, X cannot be absent or a single hydroxy or methoxy group; and when A if of the Formula IId, X is 1,3-dihalogeno or 2,4-dihalogeno.
The present invention further includes pharmaceutical compositions for treating cognitive deficiencies where the above compounds as active ingredients in therapeutically effective amounts are admixed with one or more pharmaceutically acceptable carriers, excipients, and/or diluents.
DESCRIPTION OF PREFERRED EMBODIMENTS
The quinazoline derivatives of the present invention are represented by the above Formula I. The compounds are actually tricyclic, tetracyclic, pentacyclic, or hexacyclic depending on the definition of A.
The quinazoline moiety of the compounds of the invention are described as having the formula ##STR12##
Substituent X includes one to four substituents as defined above on the aromatic ring shown in Formula I.
Preferred X substituents are independently up to four substituents selected from halogen, lower alkyl, perfluorinated lower alkyl, hydroxy, carboxy, mercapto, lower alkoxy, lower thioalkoxy, perfluorinated lower alkoxy, perfluorinated lower thioalkoxy, nitro, amino, lower alkanoylamino, aryl, aryllower alkyl, heteroaryl, heteroaryllower alkyl, trialkylsilyl, such as trimethylsilyl, or triethylsilyl, acyl, such as acetyl, benzoyl, phenylacetyl, hydrocinnamoyl and the like, perfluoroacyl, such as trifluoroacetyl, heptafluorobutyryl and the like, acyl-lower alkyl, such as acetylmethyl, benzoylmethyl, phenylacetylmethyl, hydrocinnamoylmethyl and the like, perfluoroacyl-lower alkyl, such as trifluoroacetylmethyl, heptafluorobutyrylmethyl and the like, alkyl (C 1-12 ), or aryl (or heteroaryl)carbamoyloxy, dialkyl(C 1-12 , or diaryl (or diheteroaryl)carbamoyloxy, alkyl(C 1-12 ), or aryl or (heteroaryl)carbamoylthio, and alkyl(C 1-12 ), or aryl (or heteroaryl)carbamoylalkyl, or diacylaminoalkyl, including cyclic imidoalkyl, such as acetamidomethyl, octanamidomethyl, or succinimidomethyl.
The group A shown by the above Formula IIa, IIb, and IIc is attached at two bond sites to the dihydroquinazoline moiety to form a monocyclic or bicyclic ring of members defined by n and m. The monocyclic or bicyclic ring may contain substituents defined by Y. These substituents are attached only at carbon atoms of the monocyclic or bicyclic ring. Furthermore, the monocyclic or bicyclic ring may include a heteroatom such as nitrogen, oxygen, or sulfur replacing a methylene group which is not adjacent to the quinazoline moiety. For example, the following A groups are illustrative: ##STR13##
The following is a detailed definition of the terms used to describe the compounds of the present invention shown in the above Formula I.
The term "lower" when preceding "alkyl" or "alk . . . " designates a range of 1 to 8 carbon atoms in a straight or branched hydrocarbon chain and, preferably, 1 to 4 carbon atoms when "lower" follows "aryl" or "heteroaryl". Thus, for example, lower alkyl includes methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert.-butyl, and the like. In the case of alkenyl, alkynyl, and alkanoyl, the range of carbon atoms is 2 to 8 when preceded by "lower" and includes, for example, vinyl, allyl, ethenyl, propargyl, acetyl, propionyl, and the like.
Aryl means an aromatic ring such as phenyl or phenyl substituted by lower alkyl, hydroxy, lower alkoxy, halogen, trifluoromethyl, nitro or amino, lower alkylamino, or di-loweralkyl amino.
Heteroaryl means an aromatic ring of 5 or 6 members having one or more heteroatoms such as nitrogen, oxygen, and/or sulfur and further includes a bicyclic system where another aromatic ring is condensed to the heteroaromatic ring, for example, indole, benzofuran, or benzothiophene. By way of illustration, the following are examples of heteroaromatic rings: ##STR14## where Z is NH, O or S. The heteroaromatic rings may also be substituted as aryl defined above.
A perfluorinated lower alkyl or aryl group is any of the lower alkyl or aryl groups defined above where all of the hydrogen atoms attached to the carbon atoms on the hydrocarbon skeleton have been replaced by a fluorine atom, e.g., trifluoromethyl.
Halogen means fluorine, chlorine, bromine, and iodine.
Included as part of the present invention are novel compounds of the Formula I.
Preferred are compounds of the formula ##STR15## wherein A represents ##STR16## in which n is 1-10, P is a bond or (CH 2 ) m in which m is 0-4, wherein a nitrogen, oxygen or sulfur atom may replace a methylene group in ring A and attached to a carbon atom in ring A is Y, in which Y is hydrogen, hydroxy, lower alkoxy, lower alkyl, aryl, heteroaryl, keto, lower alkoxy carbonyl or lower alkanoyl;
R is hydrogen, hydroxy, lower alkyl, lower alkoxy, lower alkenyl, lower alkynyl, aryl, aryloxy, aryllower alkyl, heteroaryl, or heteroaryllower alkyl; and
X is absent or one to four substituents selected from halogen, lower alkyl, perfluorinated lower alkyl, hydroxy, carboxy, mercapto, lower alkoxy, lower thioalkoxy, perfluorinated lower alkoxy, perfluorinated lower thioalkoxy, nitro, amino, lower alkanoylamino, aryl, aryllower alkyl, heteroaryl, and heteroaryllower alkyl, Z is defined above; or a pharmaceutically acceptable acid addition salt thereof; with the provision that when A is of the Formula IId, X is 1,3-dihalogeno.
More preferred are compounds of Formula IV, wherein
Y is hydrogen, hydroxy, carboxy, lower alkoxy, lower alkyl, keto, lower alkoxycarbonyl, and lower alkanoyl;
R is hydrogen, hydroxy, lower alkyl, lower alkoxy, lower alkenyl, or lower alkynyl; and
X is absent or one to four substituents selected from halogen, lower alkyl, perfluorinated lower alkyl, hydroxy, carboxy, lower alkoxy, perfluorinated lower alkoxy, nitro, amino, or lower alkanoyl amino and lower alkylcarbamoyloxy.
Most preferred are compounds of Formula IV, wherein Y and R are hydrogen; n is 1 to 3, and m is 0 to 3, and X is absent or one to four substituents selected from hydrogen, halogen, lower alkyl, and perfluorinated lower alkyl. Especially preferred of these are those compounds wherein X is absent or one to four substituents selected from fluoro, chloro, bromo, iodo, methyl, methylcarbamoyloxy, heptylcarbamoyloxy, and trifluoromethyl.
Particularly valuable are:
1-methyl-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
2-methyl-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
3-methyl-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
4-methyl-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
1-chloro-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
2-chloro-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
3-chloro-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
4-chloro-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
1-bromo-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
2-bromo-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
3-bromo-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
4-bromo-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
1-fluoro-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
2-fluoro-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
3-fluoro-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
4-fluoro-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
1-(trifluoromethyl)-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
2-(trifluoromethyl)-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
3-(trifluoromethyl)-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
4-(trifluoromethyl)-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
1,2-dichloro-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
1,3-dichloro-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
1,4-dichloro-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
2,3-dichloro-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
2,4-dichloro-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
3,4-dichloro-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
1,2-dibromo-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
1,3-dibromo-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
1,4-dibromo-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
2,3-dibromo-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
2,4-dibromo-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
3,4-dibromo-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
2,3-dimethoxy-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
2,4-dimethoxy-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
3,4-dimethoxy-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
1,2-dimethyl-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
1,3-dimethyl-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
1,4-dimethyl-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
2,3-dimethyl-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
2,4-dimethyl-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
3,4-dimethyl-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine,
3-chloro-1-methyl-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-imine
1-methyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-imine,
2-methyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-imine,
3-methyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-imine,
4-methyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-imine,
1-chloro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline-11-imine,
2-chloro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-imine,
3-chloro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-imine,
4-chloro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-imine,
1-bromo-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-imine,
2-bromo-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-imine,
3-bromo-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-imine,
4-bromo-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-imine,
1,2-dichloro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-imine,
1,3-dichloro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-imine,
1,4-dichloro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-imine,
2,3-dichloro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-imine, 2,4-dichloro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-imine,
3,4-dichloro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-imine,
1,2-dibromo-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-imine,
1,3-dibromo-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-imine,
1,4-dibromo-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-imine,
2,3-dibromo-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-imine,
2,4-dibromo-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-imine,
3,4-dibromo-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-imine,
1-methyl-2,3-dihydropyrrolo[2,1-b]quinazolin-9(1H)-imine,
2-methyl-2,3-dihydropyrrolo[2,1-b]quinazolin-9(1H)-imine,
3-methyl-2,3-dihydropyrrolo[2,1-b]quinazolin-9(1H)-imine,
4-methyl-2,3-dihydropyrrolo[2,1-b]quinazolin-9(1H)-imine,
1-chloro-2,3-dihydropyrrolo[2,1-b]quinazolin-9(1H)-imine,
2-chloro-2,3-dihydropyrrolo[2,1-b]quinazolin-9(1H)-imine,
3-chloro-2,3-dihydropyrrolo[2,1-b]quinazolin-9(1H)-imine,
4-chloro-2,3-dihydropyrrolo[2,1-b]quinazolin-9(1H)-imine,
1-bromo-2,3-dihydropyrrolo[2,1-b]quinazolin-9(1H)-imine,
2-bromo-2,3-dihydropyrrolo[2,1-b]quinazolin-9(1H)-imine,
3-bromo-2,3-dihydropyrrolo[2,1-b]quinazolin-9(1H)-imine,
4-bromo-2,3-dihydropyrrolo[2,1-b]quinazolin-9(1H)-imine,
1-methyl-11H-pyrido[2,1-b]quinazolin-11-imine,
2-methyl-11H-pyrido[2,1-b]quinazolin-11-imine,
3-methyl-11H-pyrido[2,1-b]quinazolin-11-imine,
4-methyl-11H-pyrido[2,1-b]quinazolin-11-imine,
1-chloro-11H-pyrido[2,1-b]quinazolin-11-imine,
2-chloro-11H-pyrido[2,1-b]quinazolin-11-imine,
3-chloro-11H-pyrido[2,1-b]quinazolin-11-imine,
4-chloro-11H-pyrido[2,1-b]quinazolin-11-imine,
1-fluoro-11H-pyrido[2,1-b]quinazolin-11-imine,
2-fluoro-11H-pyrido[2,1-b]quinazolin-11-imine,
3-fluoro-11H-pyrido[2,1-b]quinazolin-11-imine,
4-fluoro-11H-pyrido[2,1-b]quinazolin-11-imine,
1-bromo-11H-pyrido[2,1-b]quinazolin-11-imine,
2-bromo-11H-pyrido[2,1-b]quinazolin-11-imine,
3-bromo-11H-pyrido[2,1-b]quinazolin-11-imine,
4-bromo-11H-pyrido[2,1-b]quinazolin-11-imine,
1-(trifluoromethyl)-11H-pyrido[2,1-b]quinazolin-11-imine,
2-(trifluoromethyl)-11H-pyrido[2,1-b]quinazolin-11-imine,
3-(trifluoromethyl)-11H-pyrido[2,1-b]quinazolin-11-imine,
4-(trifluoromethyl)-11H-pyrido[2,1-b]quinazolin-11-imine,
1-(methylthio)-11H-pyrido[2,1-b]quinazolin-11-imine,
2-(methylthio)-11H-pyrido[2,1-b]quinazolin-11-imine,
3-(methylthio)-11H-pyrido[2,1-b]quinazolin-11-imine,
4-(methylthio)-11H-pyrido[2,1-b]quinazolin-11-imine,
1,2-dichloro-11H-pyrido[2,1-b]quinazolin-11-imine,
1,3-dichloro-11H-pyrido[2,1-b]quinazolin-11-imine,
1,4-dichloro-11H-pyrido[2,1-b]quinazolin-11-imine,
2,3-dichloro-11H-pyrido[2,1-b]quinazolin-11-imine,
2,4-dichloro-11H-pyrido[2,1-b]quinazolin-11-imine,
3,4-dichloro-11H-pyrido[2,1-b]quinazolin-11-imine,
1,3-dimethoxy-11H-pyrido[2,1-b]quinazolin-11-imine,
2,3-dimethoxy-11H-pyrido[2,1-b]quinazolin-11-imine,
2,4-dimethoxy-11H-pyrido[2,1-b]quinazolin-11-imine,
3,4-dimethoxy-11H-pyrido[2,1-b]quinazolin-11-imine,
1,2-dimethyl-11H-pyrido[2,1-b]quinazolin-11-imine,
1,3-dimethyl-11H-pyrido[2,1-b]quinazolin-11-imine,
1,4-dimethyl-11H-pyrido[2,1-b]quinazolin-11-imine,
2,3-dimethyl-11H-pyrido[2,1-b]quinazolin-11-imine,
2,4-dimethyl-11H-pyrido[2,1-b]quinazolin-11-imine,
3,4-dimethyl-11H-pyrido[2,1-b]quinazolin-11-imine,
2-(methylcarbamoyloxy)-11H-pyrido[2,1-b]quinazolin-11-imine,
1-chloro-2-(methylcarbamoyloxy)-11H-pyrido[2,1-b]quinaolin-11-imine,
3-chloro-2-(methylcarbamoyloxy)-11H-pyrido[2,1-b]quinaolin-11-imine,
1-chloro-3-(methylcarbamoyloxy)-11H-pyrido[2,1-b]quinaolin-11-imine,
2-(heptylcarbamoyloxy)-11H-pyrido[2,1-b]quinazolin-11-imine,
3-(heptylcarbamoyloxy)-11H-pyrido[2,1-b]quinazolin-11-imine,
1-chloro-3-(heptylcarbamoyloxy)-11H-pyrido[2,1-b]quinazolin-11-imine,
3-chloro-2-(heptylcarbamoyloxy)-11H-pyrido[2,1-b]quinazolin-11-imine,
1,3-dichloro-2-(heptylcarbamoyloxy)-11H-pyrido[2,1-b]quinazolin-11-imine,
1-chloro-3-methyl-11H-pyrido[2,1-b]quinazolin-11-imine,
1-methyl-3-chloro-11H-pyrido[2,1-b]quinazolin-11-imine,
1,3-dichloro-11H-pyrido[2,1-b]quinazolin-11-methylimine,
1,3-dichloro-11H-pyrido[2,1-b]quinazolin-11-(2-phenylethyl)-imine,
1,3-difluoro-11H-pyrido[2,1-b]quinazolin-11-imine,
1-fluoro-3-bromo-11H-pyrido[2,1-b]quinazolin-11-imine,
1-fluoro-3-iodo-11H-pyrido[2,1-b]quinazolin-11-imine,
1-chloro-3-fluoro-11H-pyrido[2,1-b]quinazolin-11-imine,
1-chloro-3-bromo-11H-pyrido[2,1-b]quinazolin-11-imine,
1-chloro-3-iodo-11H-pyrido[2,1-b]quinazolin-11-imine,
1-bromo-3-fluoro-11H-pyrido[2,1-b]quinazolin-11-imine,
1-bromo-3-chloro-11H-pyrido[2,1-b]quinazolin-11-imine,
1-bromo-3-iodo-11H-pyrido[2,1-b]quinazolin-11-imine,
1,3-dibromo-11H-pyrido[2,1-b]quinazolin-11-imine,
1-iodo-3-fluoro-11H-pyrido[2,1-b]quinazolin-11-imine,
1-iodo-3-chloro-11H-pyrido[2,1-b]quinazolin-11-imine,
1-iodo-3-bromo-11H-pyrido[2,1-b]quinazolin-11-imine,
1,3-diiodo-11H-pyrido[2,1-b]quinazolin-11-imine, or a pharmaceutically acceptable acid addition salt thereof.
A second preferred series of compounds of Formula I are those of Formula V ##STR17## wherein A represents ##STR18## in which n is 1-10, P is a bond or (CH 2 ) m in which m is 0-3, wherein a nitrogen, oxygen, or sulfur atom may replace a methylene group (CH 2 ) in ring A, which methylene is not adjacent to the quinazoline moiety; attached to a carbon atom in ring A is Y, in which Y is hydrogen, hydroxy, carboxy, lower alkoxy, lower alkyl, aryl, heteroaryl, keto, lower alkoxycarbonyl, or lower alkanoyl including oxime derivatives of the alkanoyl compounds; R and R' are each independently hydrogen, hydroxy, lower alkyl, lower alkoxy, lower alkenyl, lower alkynyl, aryl, aryloxy, aryl lower alkyl, heteroaryl, or heteroaryl lower alkyl and, when taken together, may form a three- to six-membered ring optionally containing one to three heteroatoms selected from nitrogen, oxygen, and sulfur; and X is absent or one to four substituents selected from halogen, lower alkyl, perfluorinated lower alkyl, perfluorinated lower alkoxy, lower alkylthio, lower alkoxy, and alkyl(C 1 -C 12 )carbamoyloxy; Z is as defined above; or a pharmaceutically acceptable salt thereof; with the provision that when A is of the Formula IId, X is 1,3-dihalogeno.
More preferred of the second series are compounds of Formula V wherein Y is hydrogen, hydroxy, carboxy, lower alkoxy, lower alkyl, aryl, heteroaryl, lower alkoxycarbonyl, or lower alkanoyl.
Most preferred of the second series are those of Formula V wherein Y is hydrogen, methyl or phenyl; n is 1 to 3, and m is 0 to 2, and X is one to four substituents selected from chloro, bromo, fluoro, iodo, methylthio, trifluoromethoxy, methyl, methoxy, methylcarbamoyloxy, heptylcarbamoyloxy, and trifluoromethyl.
Particularly valuable of the second series are:
1-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
2-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
4-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-chloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
2-chloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3-chloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
4-chloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-fluoro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
2-fluoro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3-fluoro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
4-fluoro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-bromo-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
2-bromo-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3-bromo-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
4-bromo-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-(trifluoromethyl)-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
2-(trifluoromethyl)-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3-(trifluoromethyl)-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
4-(trifluoromethyl)-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-(methylthio)-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
2-(methylthio)-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3-(methylthio)-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
4-(methylthio)-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1,2-dichloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1,3-dichloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1,4-dichloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
2,3-dichloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
2,4-dichloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3,4-dichloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3,4-dibromo-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
2,3-dimethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
2,4-dimethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3,4-dimethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1,2-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1,3-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1,4-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
2,3-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
2,4-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3,4-dimethyl-6,7,8,9,10,12-hexahydroazepino2,1-b]quinazoline,
2-ethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
2-(methylcarbamoyloxy)-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-chloro-2-(methylcarbamoyloxy)-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3-chloro-2-(methylcarbamoyloxy)-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1,3-dichloro-2-(methylcarbamoyloxy)-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
2-(heptylcarbamoyloxy)-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-chloro-2-(heptylcarbamoyloxy)-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3-chloro-2-(heptylcarbamoyloxy)-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1,3-dichloro-2-(heptylcarbamoyloxy)-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-chloro-2-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-chloro-3-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-chloro-4-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
2-chloro-1-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3-chloro-1-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
4-chloro-1-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3-chloro-1-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3-chloro-2-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3-chloro-4-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
4-chloro-1-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
4-chloro-2-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
4-chloro-3-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3-chloro-2,4-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1,3-dichloro-2-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1,3-dichloro-4-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1,3-dichloro-2,4-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-chloro-7,7-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3-chloro-7,7-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-chloro-9,9-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3-chloro-9,9-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-chloro-12,12-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3-chloro-12,12-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1,3-dichloro-7,7-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1,3-dichloro-9,9-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1,3-dichloro-12,12-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1,3-dichloro-7,7,9,9-tetramethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-chloro-7,7,9,9-tetramethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3-chloro-7,7,9,9-tetramethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1,3-dichloro-7,7,9,9,12,12-hexamethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3-chloro-12-methylene-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3-chloro-12-isopropylidene-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline
1,3-dichloro-12-methylene-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
8,10-dichloro-1,2,5,11-tetrahydro-4H-[1,4]thiazepino[5,4-b]quinazoline,
8-chloro-1,2,5,11-tetrahydro-4H-[1,4]thiazepino[5,4-b]quinazoline,
8,10-dichloro-1,2,5,11-tetrahydro-4H-[1,4]thiazepino[5,4-b]quinazoline-3,3-dioxide,
1,3-dichloro-8,9,10,12-tetrahydroazepino[2,1-b]quinazolin-7(6H)-one,
1,3-dichloro-8,9,10,12-tetrahydroazepino[2,1-b]quinazolin-8(6H)-one,
1,3-dichloro-8,9,10,12-tetrahydroazepino[2,1-b]quinazolin-9(6H)-one,
1-methyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
2-methyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
3-methyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
4-methyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1-chloro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
2-chloro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
3-chloro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
4-chloro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1-methoxy-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
2-methoxy-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
3-methoxy-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
4-methoxy-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1-fluoro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
2-fluoro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
3-fluoro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
4-fluoro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1-bromo-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
2-bromo-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
3-bromo-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
4-bromo-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1-(trifluoromethyl)-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
2-(trifluoromethyl)-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
3-(trifluoromethyl)-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
4-(trifluoromethyl)-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1-(methylthio)-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
2-(methylthio)-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
3-(methylthio)-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
4-(methylthio)-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1,2-dichloro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1,4-dichloro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
2,3-dichloro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
2,4-dichloro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
3,4-dichloro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
3,4 -dibromo-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
2,3-dimethoxy-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
2,4-dimethoxy-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
3,4-dimethoxy-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1,2-dimethyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1,3-dimethyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1,4-dimethyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
2,3-dimethyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
2,4-dimethyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
3,4-dimethyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
2-ethyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
2-(methylcarbamoyloxy)-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1-chloro-2-(methylcarbamoyloxy)-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
3-chloro-2-(methylcarbamoyloxy)-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-2-(methylcarbamoyloxy)-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
2-(heptylcarbamoyloxy)-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1-chloro-2-(heptylcarbamoyloxy)-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
3-chloro-2-(heptylcarbamoyloxy)-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-2-(heptylcarbamoyloxy)-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1-chloro-2-methyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1-chloro-3-methyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1-chloro-4-methyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
2-chloro-1-methyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
3-chloro-1-methyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
4-chloro-1-methyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
3-chloro-1-methyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
3-chloro-2-methyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
3-chloro-2-methyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
3-chloro-4-methyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
4-chloro-1-methyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
4-chloro-2-methyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
3-chloro-2,4-dimethyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-2-methyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-4-methyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-2,4-dimethyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-7-thia-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-7-oxa-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-7-thia-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline-7,7-dioxide,
5-chloro-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
6-chloro-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
7-chloro-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
8-chloro-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
5-methyl-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
6-methyl-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
7-methyl-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
8-methyl-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
5,6-dichloro-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
5,7-dichloro-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
5,8-dichloro-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
6,7-dichloro-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
6,8-dichloro-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
6,8-dichloro-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
7,8-dichloro-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
6-chloro-8-methyl-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
8-chloro-6-methyl-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
6,8-dichloro-9-methyl-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
6,8-dichloro-9,9-dimethyl-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
6-chloro-8,9-dimethyl-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
8-chloro-6,9-dimethyl-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
6-chloro-8,9,9-trimethyl-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
8-chloro-6,9,9-trimethyl-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
6-chloro-9-methylene-9(1H)-2,3-dihydropyrrolo[2,1-b]quinazoline,
6-chloro-9-isopropylidene-9(1H)-2,3-dihydropyrrolo[2,1-b]quinazoline,
5,6-dibromo-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
5,7-dibromo-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
5,8-dibromo-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
6,7-dibromo-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
6,8-dibromo-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
7,8-dibromo-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
2-phenyl-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
2,2-diphenyl-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
6-chloro-2-phenyl-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
6,8-dichloro-2-phenyl-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
8,8-diphenyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1-chloro-8,8-diphenyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
3-chloro-8,8-diphenyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1-chloro-8,8-diphenyl-7-oxa-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline
3-chloro-8,8-diphenyl-7-oxa-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline
8,8-diphenyl-7-oxa-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-8,8-diphenyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-8,8-diphenyl-7-oxa-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
8,8-diphenyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-chloro-8,8-diphenyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3-chloro-8,8-diphenyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1,3-dichloro-8,8-diphenyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1,3-dichloro-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,3-dichloro-6,7,8,9,10,12-hexahydro-6,10-methanoazepino[2,1-b]quinazoline,
1,3-dichloro-6,7,8,9,10,12-hexahydro-6,9-methanoazepino[2,1-b]quinazoline,
1,3-dichloro-6,7,8,9,10,12-hexahydro-7,10-methanoazepino[2,1-b]quinazoline,
3-chloro-6,7,8,9,10,12-hexahydro-7,10-methanoazepino[2,1-b]quinazoline,
2-chloro-1,4-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3-chloro-1,4-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-chloro-2,3-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-chloro-3,4-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-chloro-2,4-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
2-chloro-3,4-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
2-chloro-1,3-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3-chloro-1,2-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3-chloro-2,4-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
4-chloro-1,2-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
4-chloro-1,3-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
4-chloro-2,3-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1,3-dichloro-2,4-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1,2-dichloro-3,4-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
2,3-dichloro-1,4-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
2,4-dichloro-1,3-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1,4-dichloro-2,3-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3,4-dichloro-1,2-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
2-chloro-1,4-dimethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3-chloro-1,4-dimethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-chloro-2,3-dimethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-chloro-3,4-dimethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-chloro-2,4-dimethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
2-chloro-3,4-dimethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
2-chloro-1,3-dimethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3-chloro-1,2-dimethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3-chloro-2,4-dimethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
4-chloro-1,2-dimethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
4-chloro-1,3-dimethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
4-chloro-2,3-dimethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1,3-dichloro-2,4-dimethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline
1,2-dichloro-3,4-dimethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline
2,3-dichloro-1,4-dimethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline
2,4-dichloro-1,3-dimethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline
1,4-dichloro-2,3-dimethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline
3,4-dichloro-1,2-dimethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline
1,3-dichloro-2-methylthio-4-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
2,4-dichloro-3-methylthio-4-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-chloro-3-trifluoromethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-chloro-3-trifluoromethoxy-4-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
2-chloro-4-trifluoromethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3-chloro-1-trifluoromethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1,3-bis(trifluoromethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
2,4-bis(trifluoromethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-chloro-2,3-dimethoxy-4-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1,2-dimethyl-3-chloro-4-methoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1,3-dichloro-2-fluoro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-bromo-3-chloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-bromo-3-trifluoromethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline
3-bromo-1-chloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
3-bromo-1-trifluoromethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline
1,3-dibromo-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline, and
2,4-dibromo-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-fluoro-3-chloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-fluoro-3-bromo-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-fluoro-3-iodo-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-chloro-3-fluoro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-chloro-3-bromo-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-chloro-3-iodo-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-bromo-3-fluoro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-bromo-3-chloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-bromo-3-iodo-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
1-iodo-3-fluoro-6,7,8,9,10,12-hexahydroazepine[2,1-b]quinazoline,
1-iodo-3-chloro-6,7,8,9,10,12-hexahydroazepine[2,1-b]quinazoline,
1-iodo-3-bromo-6,7,8,9,10,12-hexahydroazepine[2,1-b]quinazoline,
1,3-diiodo-6,7,8,9,10,12-hexahydroazepine[2,1-b]quinazoline,
1,3-dichloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazolin-12-ol,
1-fluoro-3-chloro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1-fluoro-3-bromo-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1-fluoro-3-iodo-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1-chloro-3-fluoro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1-chloro-3-bromo-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1-chloro-3-iodo-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1-bromo-3-fluoro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1-bromo-3-chloro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1-bromo-3-iodo-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1-iodo-3-fluoro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1-iodo-3-chloro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1-iodo-3-bromo-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
1,3-diiodo-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
6,8-difluoro-1,2,3-tetrahydropyrrolo[2,1-b]quinazoline,
6-fluoro-8-chloro-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
6-fluoro-8-bromo-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
6-fluoro-8-iodo-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
6-chloro-8-fluoro-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
6-chloro-8-bromo-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
6-chloro-8-iodo-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
6-bromo-8-fluoro-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
6-bromo-8-chloro-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
6-bromo-8-iodo-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
6,8-dibromo-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
6-iodo-8-fluoro-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
6-iodo-8-chloro-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
6-iodo-8-bromo-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
6,8-diiodo-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
1-methyl-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
2-methyl-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3-methyl-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
4-methyl-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-chloro-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
2-chloro-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3-chloro-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
4-chloro-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-fluoro-6,7,8,9-tetrahydro-11H-6,8-methanopyrido[2,1-b]quinazoline,
2-fluoro-6,7,8,9-tetrahydro-11H-6,8-methanopyrido[2,1-b]quinazoline,
3-fluoro-6,7,8,9-tetrahydro-11H-6,8-methanopyrido[2,1-b]quinazoline,
4-fluoro-6,7,8,9-tetrahydro-11H-6,8-methanopyrido[2,1-b]quinazoline,
1-bromo-6,7,8,9-tetrahydro-11H-6,8-methanopyrido[2,1-b]quinazoline,
2-bromo-6,7,8,9-tetrahydro-11H-6,8-methanopyrido[2,1-b]quinazoline,
3-bromo-6,7,8,9-tetrahydro-11H-6,8-methanopyrido[2,1-b]quinazoline,
4-bromo-6,7,8,9-tetrahydro-11H-6,8-methanopyrido[2,1-b]quinazoline,
1-(trifluoromethyl)-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
2-(trifluoromethyl)-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3-(trifluoromethyl)-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
4-(trifluoromethyl)-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-(methylthio)-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
2-(methylthio)-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3-(methylthio)-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
4-(methylthio)-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,2-dichloro-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,3-dichloro-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,4-dichloro-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
2,3-dichloro-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
2,4-dichloro-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3,4-dichloro-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,3-dimethoxy-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
2,3-dimethoxy-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
2,4-dimethoxy-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3,4-dimethoxy-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,2-dimethyl-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,3-dimethyl-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,4-dimethyl-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
2,3-dimethyl-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
2,4-dimethyl-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3,4-dimethyl-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
2-(methylcarbamoyloxy)-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-chloro-2-(methylcarbamoyloxy)-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3-chloro-2-(methylcarbamoyloxy)-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-chloro-3-(methylcarbamoyloxy)-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
2-(heptylcarbamoyloxy)-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3-(heptylcarbamoyloxy)-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-chloro-3-(heptylcarbamoyloxy)-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3-chloro-2-(heptylcarbamoyloxy)-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,3-dichloro-2-(heptylcarbamoyloxy)-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-chloro-2-methyl-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-chloro-3-methyl-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-chloro-4-methyl-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
2-chloro-1-methyl-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3-chloro-1-methyl-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
4-chloro-1-methyl-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3-chloro-1-methyl-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3-chloro-2-methyl-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3-chloro-4-methyl-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
4-chloro-1-methyl-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
4-chloro-2-methyl-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-methyl-3-chloro-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3-chloro-1,4-dimethyl-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-chloro-3-methyl-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-methyl-3-chloro-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,3-dichloro-2-methyl-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,3-dichloro-4-methyl-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,3-dichloro-2,4-dimethyl-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-chloro-11,11-dimethyl-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3-chloro-11,11-dimethyl-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,3-dichloro-11-methyl-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,3-dichloro-11,11-dimethyl-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3-chloro-11,11-methylene-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,3-dichloro-11-isopropylidene-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,3-dichloro-11-methylene-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,3-difluoro-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-fluoro-3-bromo-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline
1-fluoro-3-iodo-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-chloro-3-fluoro-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-chloro-3-bromo-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline
1-chloro-3-iodo-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-bromo-3-fluoro-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline
1-bromo-3-chloro-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline
1-bromo-3-iodo-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,3-dibromo-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-iodo-3-fluoro-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-iodo-3-chloro-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-iodo-3-bromo-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,3-diiodo-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-methyl-6,9 -dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
2-methyl-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3-methyl-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
4-methyl-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-chloro-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
2-chloro-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3-chloro-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
4-chloro-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-fluoro-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
2-fluoro-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3-fluoro-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
4-fluoro-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-bromo-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
2-bromo-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3-bromo-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
4-bromo-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-(trifluoromethyl)-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
2-(trifluoromethyl)-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3-(trifluoromethyl)-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
4-(trifluoromethyl)-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-(methylthio)-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
2-(methylthio)-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3-(methylthio)-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
4-(methylthio)-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,2-dichloro-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,3-dichloro-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,4-dichloro-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
2,3-dichloro-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
2,4-dichloro-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3,4-dichloro-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,3-dimethoxy-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
2,3-dimethoxy-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
2,4-dimethoxy-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3,4-dimethoxy-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,2-dimethyl-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,3-dimethyl-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,4-dimethyl-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
2,3-dimethyl-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
2,4-dimethyl-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3,4-dimethyl-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
2-(methylcarbamoyloxy)-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-chloro-2-(methylcarbamoyloxy)-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3-chloro-2-(methylcarbamoyloxy)-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-chloro-3-(methylcarbamoyloxy)-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
2-(heptylcarbamoyloxy)-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3-(heptylcarbamoyloxy)-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-chloro-3-(heptylcarbamoyloxy)-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3-chloro-2-(heptylcarbamoyloxy)-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,3-dichloro-2-(heptylcarbamoyloxy)-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-chloro-2-methyl-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-chloro-3-methyl-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-chloro-4-methyl-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
2-chloro-1-methyl-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3-chloro-1-methyl-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
4-chloro-1-methyl-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3-chloro-1-methyl-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3-chloro-2-methyl-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3-chloro-4-methyl-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
4-chloro-1-methyl-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
4-chloro-2-methyl-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-methyl-3-chloro-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3-chloro-1,4-dimethyl-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-chloro-3-methyl-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-methyl-3-chloro-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,3-dichloro-2-methyl-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,3-dichloro-4-methyl-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,3-dichloro-2,4-dimethyl-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-chloro-11,11-dimethyl-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline
3-chloro-11,11-dimethyl-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline
1,3-dichloro-11-methyl-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,3-dichloro-11,11-dimethyl-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
3-chloro-11-methylene-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,3-dichloro-11-isopropylidene-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,3-dichloro-11-methylene-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,3-dichloro-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-fluoro-3-bromo-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-chloro-3-fluoro-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-chloro-3-bromo-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-chloro-3-iodo-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-bromo-3-fluoro-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-bromo-3-chloro-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-bromo-3-iodo-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,3-dibromo-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-iodo-3-fluoro-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-iodo-3-chloro-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-iodo-3-bromo-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1,3-diiodo-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline,
1-methyl-11H-pyrido[2,1-b]quinazoline,
2-methyl-11H-pyrido[2,1-b]quinazoline,
3-methyl-11H-pyrido[2,1-b]quinazoline,
4-methyl-11H-pyrido[2,1-b]quinazoline,
1-chloro-11H-pyrido[2,1-b]quinazoline,
2-chloro-11H-pyrido[2,1-b]quinazoline,
3-chloro-11H-pyrido[2,1-b]quinazoline,
4-chloro-11H-pyrido[2,1-b]quinazoline,
1-fluoro-11H-pyrido[2,1-b]quinazoline,
2-fluoro-11H-pyrido[2,1-b]quinazoline,
3-fluoro-11H-pyrido[2,1-b]quinazoline,
4-fluoro-11H-pyrido[2,1-b]quinazoline,
1-bromo-11H-pyrido[2,1-b]quinazoline,
2-bromo-11H-pyrido[2,1-b]quinazoline,
3-bromo-11H-pyrido[2,1-b]quinazoline,
4-bromo-11H-pyrido[2,1-b]quinazoline,
1-(trifluoromethyl)-11H-pyrido[2,1-b]quinazoline,
2-(trifluoromethyl)-11H-pyrido[2,1-b]quinazoline,
3-(trifluoromethyl)-11H-pyrido[2,1-b]quinazoline,
4-(trifluoromethyl)-11H-pyrido[2,1-b]quinazoline,
1-(methylthio)-11H-pyrido[2,1-b]quinazoline,
2-(methylthio)-11H-pyrido[2,1-b]quinazoline,
3-(methylthio)-11H-pyrido[2,1-b]quinazoline,
4-(methylthio)-11H-pyrido[2,1-b]quinazoline,
1,2-dichloro-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-11H-pyrido[2,1-b]quinazoline,
1,4-dichloro-11H-pyrido[2,1-b]quinazoline,
2,3-dichloro-11H-pyrido[2,1-b]quinazoline,
2,4-dichloro-11H-pyrido[2,1-b]quinazoline,
3,4-dichloro-11H-pyrido[2,1-b]quinazoline,
1,3-dimethoxy-11H-pyrido[2,1-b]quinazoline,
2,3-dimethoxy-11H-pyrido[2,1-b]quinazoline,
2,4-dimethoxy-11H-pyrido[2,1-b]quinazoline,
3,4-dimethoxy-11H-pyrido[2,1-b]quinazoline,
1,2-dimethyl-11H-pyrido[2,1-b]quinazoline,
1,3-dimethyl-11H-pyrido[2,1-b]quinazoline,
1,4-dimethyl-11H-pyrido[2,1-b]quinazoline,
2,3-dimethyl-11H-pyrido[2,1-b]quinazoline,
2,4-dimethyl-11H-pyrido[2,1-b]quinazoline,
3,4-dimethyl-11H-pyrido[2,1-b]quinazoline,
2-(methylcarbamoyloxy)-11H-pyrido[2,1-b]quinazoline,
1-chloro-2-(methylcarbamoyloxy)-11H-pyrido[2,1-b]quinazoline,
3-chloro-2-(methylcarbamoyloxy)-11H-pyrido[2,1-b]quinazoline,
1-chloro-3-(methylcarbamoyloxy)-11H-pyrido[2,1-b]quinazoline,
2-(heptylcarbamoyloxy)-11H-pyrido[2,1-b]quinazoline,
3-(heptylcarbamoyloxy)-11H-pyrido[2,1-b]quinazoline,
1-chloro-3-(heptylcarbamoyloxy)-11H-pyrido[2,1-b]quinazoline,
3-chloro-2-(heptylcarbamoyloxy)-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-2-(heptylcarbamoyloxy)-11H-pyrido[2,1-b]quinazoline,
1-chloro-2-methyl-11H-pyrido[2,1-b]quinazoline,
1-chloro-3-methyl-11H-pyrido[2,1-b]quinazoline,
1-chloro-4-methyl-11H-pyrido[2,1-b]quinazoline,
2-chloro-1-methyl-11H-pyrido[2,1-b]quinazoline,
3-chloro-1-methyl-11H-pyrido[2,1-b]quinazoline,
4-chloro-1-methyl-11H-pyrido[2,1-b]quinazoline,
3-chloro-1-methyl-11H-pyrido[2,1-b]quinazoline,
3-chloro-2-methyl-11H-pyrido[2,1-b]quinazoline,
3-chloro-4-methyl-11H-pyrido[2,1-b]quinazoline,
4-chloro-1-methyl-11H-pyrido[2,1-b]quinazoline,
4-chloro-2-methyl-11H-pyrido[2,1-b]quinazoline,
1-methyl-3-chloro-11H-pyrido[2,1-b]quinazoline,
3-chloro-1,4-dimethyl-11H-pyrido[2,1-b]quinazoline,
1-chloro-3-methyl-11H-pyrido[2,1-b]quinazoline,
1-methyl-3-chloro-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-2-methyl-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-4-methyl-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-2,4-dimethyl-11H-pyrido[2,1-b]quinazoline,
1-chloro-11,11-dimethyl-11H-pyrido[2,1-b]quinazoline,
3-chloro-11,11-dimethyl-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-11-methyl-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-11,11-dimethyl-11H-pyrido[2,1-b]quinazoline,
3-chloro-11-methylene-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-11-isopropylidene-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-11-methylene-11H-pyrido[2,1-b]quinazoline,
1,3-difluoro-11H-pyrido[2,1-b]quinazoline,
1-fluoro-3-bromo-11H-pyrido[2,1-b]quinazoline,
1-fluoro-3-iodo-11H-pyrido[2,1-b]quinazoline,
1-chloro-3-fluoro-11H-pyrido[2,1-b]quinazoline,
1-chloro-3-bromo-11H-pyrido[2,1-b]quinazoline,
1-chloro-3-iodo-11H-pyrido[2,1-b]quinazoline,
1-bromo-3-fluoro-11H-pyrido[2,1-b]quinazoline,
1-bromo-3-chloro-11H-pyrido[2,1-b]quinazoline,
1-bromo-3-iodo-11H-pyrido[2,1-b]quinazoline,
1,3-dibromo-11H-pyrido[2,1-b]quinazoline,
1-iodo-3-fluoro-11H-pyrido[2,1-b]quinazoline,
1-iodo-3-chloro-11H-pyrido[2,1-b]quinazoline,
1-iodo-3-bromo-11H pyrido[2,1-b]quinazoline,
1,3-diiodo-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-methyl-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
2-methyl-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
3-methyl-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
4-methyl-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-chloro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
2-chloro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
3-chloro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
4-chloro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-fluoro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
3-fluoro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-bromo-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
2-bromo-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
3-bromo-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
4-bromo-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-(trifluoromethyl)-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
2-(trifluoromethyl)-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
3-(trifluoromethyl)-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
4-(trifluoromethyl)-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1,2-dichloro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1,3-dichloro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1,4-dichloro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
2,3-dichloro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
2,4-dichloro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
3,4-dichloro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
2,3-dimethoxy-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
2-(methylcarbamoyloxy)-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-chloro-2-(methylcarbamoyloxy)-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
3-chloro-2-(methylcarbamoyloxy)-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-chloro-3-(methylcarbamoyloxy)-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
2-(heptylcarbamoyloxy)-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
3-(heptylcarbamoyloxy)-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-chloro-3-(heptylcarbamoyloxy)-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
3-chloro-2-(heptylcarbamoyloxy)-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1,3-dichloro-4-methyl-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1,3-difluoro-11H-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-fluoro-3-chloro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-fluoro-3-bromo-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-fluoro-3-iodo-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-chloro-3-fluoro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-chloro-3-bromo-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-chloro-3-iodo-11H-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-bromo-3-fluoro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-bromo-3-chloro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-bromo-3-iodo-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1,3-dibromo-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-iodo-3-fluoro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-iodo-3-chloro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-iodo-3-bromo-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1,3-diiodo-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline, and a pharmaceutically acceptable acid addition salt thereof.
As pharmaceutically acceptable acid addition salts of the compounds of Formula I are those of inorganic and organic acids. Preferred inorganic acid salts are, for example, hydrochlorides, hydrobromides, hydroiodides, sulfates, phosphates, and the like. Preferred organic acid salts are acetates, oxalates, maleates, fumarates, lactates, malates, citrates, tartrates, succinates, benzoates, methanesulfonates, and the like. Also preferred are salts of amino acids such as glycinates, alaninates, carnitinates, cysteinates, and the like, including their corresponding N-acetyl derivatives and also salts of polyhydroxy acids as gluconates, acetylneuraminates, alginates, galacturates, galacturonates, and the like.
The compounds of the present invention or salts thereof may also form hydrates or solvates; the hydrates and solvates thereof are also included in the compounds of the present invention.
Depending on the substituents on A or substituents forming a part of M, when M represents ##STR19## of Formula I, the compounds of the present invention may also contain one or more asymmetric carbon atoms, which optical isomers and/or diastereomers are included as part of the present invention.
The compounds of the present invention and of Formula I may be prepared according to the following procedures.
When M═O, the compounds of Formula I may be prepared by reacting an anthranilic acid of the formula ##STR20## or a reactive derivative thereof, in which X is as defined above, with a lactam or cyclic iminoether or cyclic imidoyl chloride of the formulae ##STR21## in which is as defined above and Ra is alkyl of 1 to 3 carbon atoms, preferably methyl or ethyl.
Anthranilic acids of Formula VI are either commercially available or may be prepared by known methods from commercially available starting materials, e.g., prepared from the corresponding isatines: T. Sandmeyer, Helv. Chim. Acta, 2:234 (1919), by oxidation with alkaline hydrogen peroxide, following the procedure described by Baker, et al., J. Org. Chem., 17:141 (1952) for the synthesis of 3-chloroanthranilic acid.
The lactams of Formula VIIa are also either commercially available or may be prepared by known methods from commercially available materials.
Reactive derivatives of anthranilic acids are the anhydrides, also called isatoic anhydrides, 2-(sulfinylamino)benzoyl chlorides or esters, preferably methyl or ethyl, which may be used instead of the anthranilic acids per se.
When the anthranilic acids are used per se, the reaction with VIIb or VIIc takes place at temperatures at or above room temperature and, preferably, at the boiling point of the solvent. The solvent employed is a nonpolar solvent such as, for example, benzene, toluene, xylene, chloroform, methylene chloride, carbon tetrachloride, and the like. Water formed during the reaction may be removed by means of an azeotropic trap.
An isatoic anhydride or 2-(sulfinylamino)benzyl chloride may be used as a reactant with the appropriate lactam of Formula VIIa. The 2-(sulfinylamino)benzoyl chloride is prepared by known means by reacting the corresponding anthranilic acid with thionyl chloride. The reaction of the 2-(sulfinylamino)benzoyl chloride with the lactam may proceed at 0° C. to about 50° C. for about 1 to 24 hours also with the same nonpolar solvent.
An isatoic anhydride formed by action of phosgene on the corresponding anthranilic acid of Formula VI may be used as a starting material and reacted with the appropriate lactam at elevated temperatures, for example, 150° C.-200° C.
A cyclic imino ether of Formula VIIb may be used in the reactions of anthranilic acids or their esters under similar conditions of time, temperatures, and solvent. The cyclic imino ether may be available commercially or prepared from the lactam by reaction with alkylating agents such as dimethyl sulfate, triethyloxonium tetrafluoroborate, or methyl trifluoromethanesulfonate, followed by reaction with base, as described in the literature.
Anthranilic acids or esters of anthranilic acids of Formula VI, preferably methyl or ethyl, may also be used as starting materials and reacted with an imidoyl halide, e.g., chloride VIIc, prepared by treating the corresponding lactam with phosphorus oxychloride. The reaction takes place at room temperature or above (60° C.) in an organic solvent, such as chloroform.
When M═R,R', compounds of Formula I may be prepared by heating a corresponding imidoyl chloride, as prepared above, with a compound of the formula ##STR22## where X, R, and R' are as defined above. The reaction takes place at or above room temperature, preferably between 10° C. and 130° C. in an organic solvent, e.g., chloroform, toluene, chlorobenzene, or a mixture thereof for about 1 to 48 hours.
The starting compounds of Formula VII may be prepared by known methods from commercially available materials. For example, by the well-known Beckmann rearrangement from the corresponding ketoximes, either commercially available or prepared by literature methods, well known to those skilled in the art.
When both R and R' are hydrogen, the compounds of Formula I may be prepared directly from the corresponding compounds of Formula I when M═O by chemical reduction with zinc and hydrochloric acid in the presence of acetic acid. The reaction takes place at 40° C.-100° C., preferably 50° C.-60° C., and between 10 minutes to 5 hours. These compounds can also be prepared by reductive desulfurization with Raney nickel in tetrahydrofuran, or alcohol at 10° C.-100° C., preferably 60° C., of the compounds of Formula I, when M═S, readily prepared from the corresponding oxo-compounds of Formula I, M═O, as described below.
When M═NH, the compounds of Formula I may be prepared by reacting a compound of the formula ##STR23## with the appropriate lactim derivative of the Formula VIIb (lactim ether). The reactions are performed at elevated temperatures, e.g., 100° C. to 200° C., preferably 140° C., for about 1 to 5 days in inert (nitrogen or argon) atmosphere.
These compounds can also be prepared by the treatment of the cyano intermediate IX with an imidoyl chloride VIIc at 0° C.-100° C. (preferably 25° C.), for 1 to 48 hours. The imidoyl chlorides are prepared from the corresponding lactams VIIa by the treatment with phosphorus oxychloride, or analogous reagents, as is well known to those skilled in the art. The resulting compound of the Formula X ##STR24## may, if desired to form a compound where R is other than hydrogen, be treated with a corresponding bromide R--Br or iodide R--I, in the presence of sodium hydride.
Alternatively, such compounds can be obtained by the treatment of the corresponding thiones (compounds of the Formula I, where M═S, obtained as described below), with ammonia or amines R--NH 2 at elevated temperatures (60° C.-180° C.).
When M═S, the compounds of the Formula I may be prepared by reacting a compound of Formula I when M═O with phosphorus pentasulfide or the Lawesson reagent, [2,4-bis(4-methoxyphenyl)-1,3-dithia-2,4-diphosphetane-2,4-disulfide] at 100°-150° C., preferably at 110° C. in boiling toluene for 24 hours.
The compounds of the present invention and of Formula I are inhibitors of acetylcholinesterase, centrally acting with favorable distribution into the central nervous system versus the periphery. They also may be inhibitors of cholinesterase other than acetylcholinesterase, and may stop or reverse Alzheimer's disease plaques and tangles (amyloid protein) formation by inhibition of the protease enzymes responsible for their formation.
Representative compounds of the present invention have been found to possess acetylcholinesterase inhibiting effects in vitro as shown in the following table. The in vitro data was obtained according to the radiometric assay of C. D. Johnson and R. L. Russell described in Anal. Biochem., 64:229-238 (1975) and modified as described by M. R. Emmerling and H. M. Sobkowicz in Hearings Research, 32:137-146 (1988); the rat brain homogenate acetylcholinesterase inhibition data were obtained by the Ellman assay, described by G. L. Ellman, D. Courtney, V. Andres, and R. M. Feathersome, described in Biochem. Pharmacol. 7:88-95 (1961), and modified as described by M. J. Marks, D. M. Patinkin, L. D. Artman, J. B. Busch, and A. C. Collins in Pharmacol. Biochem. and Behav.15:271-279 (1981), which references are incorporated herein.
TABLE I______________________________________Inhibition of Acetylcholinesteraseby Dihydroquinazolines ##STR25## Human Red Rat Brain Blood Homogenate Electric Cell AChE AChE Eel AChEX = M = (nM) (nM) (nM)______________________________________1-Cl H.sub.2 1,700 -- --2-Cl H.sub.2 500 -- --3-Cl H.sub.2 158 1,900 2004-Cl H.sub.2 1,500 16,400 6312-CH.sub.3 H.sub.2 1,800 -- --3-CH.sub.3 H.sub.2 610 -- --4-CH.sub.3 H.sub.2 6,000 -- --1-F H.sub.2 1,900 -- --2-F H.sub.2 2,000 -- --3-F H.sub.2 2,870 -- 6004-F H.sub.2 1,600 -- 1,5003-OCH.sub.3 H.sub.2 2,800 -- --2-CN H.sub.2 6,700 -- 1,5002-C.sub.2 H.sub.5 H.sub.2 2,500 -- 1,000H H.sub.2 1,900 16,000 6101,2-DiCl H.sub.2 3,162 -- --1,3-DiCl H.sub.2 40 172 1582,3-DiCl H.sub.2 2,500 17,850 3981,4-DiCl H.sub.2 631 16,450 1002,4-DiCl H.sub.2 63 3,810 2503,4-DiCl H.sub.2 1,500 23,800 3982,4-DiCH.sub.3 H.sub.2 900 -- --2,3-DiOCH.sub.3 H.sub.2 9,000 -- 3981-CH.sub.3, 2-Cl H.sub.2 3,981 -- --2-CH.sub.3, 4-Cl H.sub.2 631 -- --1,3-DiCl, 2-Me H.sub.2 1,000 -- --3-Cl O >100,000 -- 21,0003-Cl S >100,000 -- 15,8003-Cl NH 1,260 -- 500______________________________________
TABLE II______________________________________Inhibition of Human Red Blood CellAcetylcholinesterase by Dihydroquinazolines IC.sub.50 HumanStructure AChE (nM)______________________________________ ##STR26## 60 ##STR27## 50 ##STR28## 63 ##STR29## 2,000 ##STR30## 1,000 ##STR31## 920 ##STR32## 200 ##STR33## 60 ##STR34## 63,000______________________________________
TABLE III______________________________________Inhibition of Electric Eel Acetylcholinesteraseby DihydroquinazolinesStructure IC.sub.50 Eel AChE (nM)______________________________________ ##STR35## 1,600 ##STR36## 1,600 ##STR37## 610 ##STR38## 1,000 ##STR39## 2,000 ##STR40## 1,000 ##STR41## 370 ##STR42## 4,300 ##STR43## 4,000 ##STR44## 3,100______________________________________
Thus, the compounds of the present invention may be used in treating Alzheimer's disease, senile dementias, multiple infarct dementias, and other conditions where memory and cognitive function improvement or stabilization is desired.
When the compound of the present invention is used as a therapeutic agent, it may be administered singly or as a composite by compounding with a carrier which is pharmaceutically acceptable. Compositions thereof may be determined by the solubility, chemical properties, route of administration, administration scheme, etc., of the compounds.
For example, it may be administered orally in the form of granules, fine grains, powders, tablets, hard capsules, soft capsules, syrups, emulsions, suspensions or liquids, or may be administered parenterally, i.e., intravenously or intramuscularly as an injection.
Also, by making a powder for injection, it may be used per se by preparing when using it. An organic or inorganic carrier which is in the form of solid or liquid, or a diluent, which are pharmaceutically acceptable for oral, rectal, parenteral, or local administration may be used in combination with the compound of the present invention. As excipients to be used for preparing solid preparations, for example, lactose, sucrose, starch, talc, cellulose, dextrin, kaolin, calcium carbonate, etc, are used. Liquid preparations for oral administration, that is, emulsions, syrups, suspensions, liquids, etc., contain inert diluents which are conventionally used such as water or a vegetable oil, etc. This preparation may be contained, in addition to the inert diluents, such as auxiliaries, e.g., wettables, suspension auxiliaries, sweeteners, aromatics, colorants or preservatives, etc. It may be made in the form of liquid preparations and contained in a capsule made of a substance which is absorbable such as gelatin, etc. As the preparations for parenteral administration, that is, solvents or suspending agents to be used for preparation of injections, etc., there may be mentioned, for example, water, propylene glycol, polyethylene glycol, benzyl alcohol, ethyl oleate, lecithin, etc. Preparative methods of the preparations may be based on the conventional method.
Regarding a clinical dosage, when it is used via oral administration, a dose per day is generally 1 to 1000 mg, preferably 1 to 100 mg of the compound of the present invention per an adult, but the dose may be optionally varied depending upon age, severity of disease, condition of the patient, presence or absence of simultaneous administration, etc. The above dose per day of the compound of the present invention may be administered once per day or may be administered twice or three times per day with suitable intervals by dividing it, or may be administered intermittently.
Also, when it is used as injections, it is used as the dose per day of 0.1 to 100 mg, preferably 0.1 to 50 mg as the compound of the present invention per an adult.
The following examples provide by way of illustration a detailed description of the synthesis of representative compounds of the present invention.
EXAMPLE 1
I. 3-Chloro-7,8,9,10-tetrahydroazpino[2,1-b]quinazolin-12(6H)-one
To a stirred slurry of 17.16 g of 4-chloroanthranilic acid (Aldrich) in 120 mL benzene was added 14 mL 1-aza-2-methoxy-1-cycloheptene (1) (Aldrich) and refluxed under nitrogen using an azeotropic Dean-Stark trap to remove the water/methanol formed by the reaction. After 2 hours of reflux, 5 mL of the methoxyimine (1) was added and 2 mL more after 18 hours. The mixture was then refluxed for 4 more hours. The solvent was distilled out and the excess of (1) was removed by distillation at 140° C. (bath) at 11 mm Hg. A dark brown oil formed which soon crystallized. There was a single mobile spot on TLC (4:1 chloroform-ethyl acetate, Rf=0.6, silica gel). The mixture was chromatographed using the above solvent system, the corresponding fractions concentrated in vacuo and the residue was recrystallized from hexane-ethyl acetate, giving 19.08 g of the 3-chloro-6,7,8,9-tetrahydroazepino[2,1-b]quinazolin-12(6H)-one (76.7% yield), m.p. 106°-108° C.
II. 3-Chloro-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-thione
10 g of 3-chloro-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-one was treated with 15 g of Lawesson's reagent in toluene at reflux under nitrogen, until the starting material was consumed, as checked by TLC, using chloroform as eluent (24 hours). The mixture was concentrated in vacuo and chromatographed on silica gel, using chloroform as eluent. The bright yellow material was recrystallized from hexane-ethyl acetate, giving lemon-yellow needles, m.p. 99° C.-101° C.
III. 3-Chloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline
To a solution of 2 g of 3-chloro-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-one, dissolved in 50 mL of glacial acetic acid was stirred 25 g of zinc dust with vigorous mechanical stirring. The mixture was heated to 55° C.-60° C. and concentrated hydrochloric acid was added dropwise (approximately 20 mL). The reaction was checked by TLC. Usually between 20 minutes to 5 hours were required for completion. The excess zinc was filtered off, the solution concentrated in vacuo, and basified with 20% sodium hydroxide solution. The product was extracted with tetrahydrofuran. Then the free base was chromatographed using 300:25:1 CHCl 3 :MeOH:28% aqueous ammonia. The corresponding fractions were combined, concentrated in vacuo, and dried in high vacuum providing the 3-chloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline as a white crystalline solid; m.p. 102° C.-104° C. To convert to its hydrochloride salt, the base was treated with one equivalent of 4N HCl in 50 mL absolute ethanol. The solution was concentrated in vacuo, redissolved in absolute ethanol, and concentrated in vacuo. Then the hydrochloride was recrystallized from absolute ethyl alcohol with little ethyl acetate, giving white crystals, m.p. 270° C.-271° C. (dec.).
EXAMPLE 2
I. 1,3-Dichloro-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-one
To a stirred suspension of 15 g of 4,6-dichloroanthranilic acid (prepared from the corresponding isatine: T. Sandmeyer Helv. Chim. Acta, 2:234 (1919), by oxidation with alkaline hydrogen peroxide, following the procedure described by Baker et al., J. Org. Chem., 17:141 (1952) for the synthesis of 3-chloroanthranilic acid) in 100 mL of toluene was added 20 g of 1-aza-2-methoxy-1-cycloheptene. The mixture was stirred for an hour at room temperature, followed by heating under reflux for 18 hours. Then the mixture was concentrated in vacuo and volatile material was removed at 130° C. at 1 torr. The dark brown residue was chromatographed using 8:1 chloroform-ethyl acetate to give 9 g of the desired material as a crystalline solid, m.p. 110° C.-112° C.
II. Method A: 1,3-Dichloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline hydrochloride
To a mechanically stirred solution of 1.5 g of the above quinazolinone derivative in 150 mL of glacial acetic acid at 60° C. was added 25 g of zinc dust. To the grey suspension was then added dropwise 25 mL of concentrated hydrochloric acid in 25 mL of glacial acetic acid in approximately 10 minutes and stirred for 10 minutes more at 60° C., when the reaction appeared essentially complete by TLC. Then the excess of zinc was filtered off with suction (Caution!, the zinc is pyrophoric!), washed with 4×30 mL of glacial acetic acid, and the filtrate was concentrated in vacuo. To the residue was added 50 mL of 10% aqueous sodium hydroxide and the product was extracted with tetrahydrofuran (3×150 mL). The organic extract was concentrated in vacuo and the residue was distributed between 100 mL of chloroform and 25 mL of water. The combined extract was dried with anhydrous potassium carbonate, filtered, concentrated in vacuo, and flash chromatographed on silica gel, using 95:5 (1 L) and 90:10 (1 L) of chloroform-methanol. The desired compound was obtained as a white solid after concentration in vacuo of the corresponding fractions. The base was treated with 1 equivalent of 4N HCl in 50 mL of absolute ethanol, concentrated in vacuo, redissolved in 50 mL of absolute EtOH, concentrated, repeated again. Then the solid was recrystallized from absolute EtOH-EtOAc, giving white crystals of the hydrochloride salt, m.p. 318° C.-319° C. (dec.).
II. Method B: 1,3-Dichloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline hydrochloride
To a solution of 1 g of 1,3-dichloro-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-one in 15 mL of triethylsilane was added 8 g of anhydrous zinc chloride and the mixture was refluxed under nitrogen with vigorous stirring. The triethylsilane was replenished in about 8-hour intervals. When the reaction was judged complete by TLC (300:25:1 chloroform:methanol: 28% aqueous ammonia, basified aliquot) the excess of triethylsilane and other volatiles were removed in vacuo and the residue was purified and worked-up as in Method A to give the desired 1,3-dichloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline hydrochloride as white crystalline solid.
EXAMPLE 3
I. 1,3-Dichloro-7,8,9,10-tetrahydro-6,10-methanoazepino[2,1-b]quinazolin-12(6H)-one
To a solution of 3.82 g of 6-azabicyclo[3,2,1]-octan-7-one (R. L. Augustine and L. A. Bag, J. Org. Chem., 40:1074 (1975)) in 25 mL of chloroform was added 4 mL of phosphorus oxychloride. After the mildly exothermic reaction ceased, the mixture was stirred at room temperature for 4 hours. 6.3 g of 4,6-dichloroanthranilic acid (prepared from the corresponding isatine: T. Sandmeyer, Helv. Chim. Acta, 2:234 (1919), by oxidation with alkaline hydrogen peroxide, following the procedure described by Baker, et al., J. Org. Chem., 17:141 (1952) for the synthesis of 3-chloroanthranilic acid) was dissolved in a mixture of 50 mL of chloroform and 10 mL of triethylamine. This solution was added to the stirred above solution of the imidoyl chloride at such a rate as to prevent boiling over (exothermic!), approximately 2 minutes. Then the mixture was stirred at room temperature for 4 hours and then refluxed for 3 days. Then the dark brown mixture was treated with 200 mL of 10% aqueous K 2 CO 3 . The chloroform layer was separated, aqueous layer was extracted two times with 50 mL of chloroform. The combined chloroform extract was dried with anhydrous potassium carbonate, filtered, and concentrated in vacuo. The residue was chromatographed on silica gel, using 8:1 chloroform-ethyl acetate as eluent. The corresponding fractions were concentrated in vacuo, giving a crystalline solid. This was recrystallized from ethyl acetate-hexane, giving colorless crystals.
II. 1,3-Dichloro-6,7,8,9,10,12-hexahydro-6,10-methanoazepino[2,1-b]quinazoline
To a mechanically stirred solution of 2.5 g of the above quinazolinone derivative in 150 mL of glacial acetic acid, at 60° C. was added 30 g of zinc dust. To the grey suspension was then added dropwise 30 mL of concentrated hydrochloric acid in approximately 15 minutes, followed by stirring at 60° C. for another 10 minutes, when the reaction appeared essentially complete by TLC. Then the excess of zinc was filtered with suction (Caution!, the zinc is pyrophoric!), washed with 4×30 mL of glacial acetic acid, and the filtrate was concentrated in vacuo. To the residue was added 80 mL of 20% aqueous sodium hydroxide and the product was extracted with tetrahydrofuran (100 mL and 2×50 mL). The organic extract was concentrated in vacuo and the residue was distributed between 100 mL of chloroform and 25 mL of water. The aqueous layer was extracted with 2×25 mL of chloroform. The combined extract was dried with anhydrous potassium carbonate, filtered, concentrated in vacuo, and flash chromatographed on silica gel, using 10:1 chloroform-methanol. The desired compound was obtained as a white solid. The base was treated with 1 equivalent of 4N HCl in 50 mL absolute ethanol, concentrated in vacuo, redissolved in 50 mL of absolute EtOH, concentrated, repeated again. Then the white solid was recrystallized from absolute EtOH-EtOAc, giving white crystals of the hydrochloride salt, m.p. 265° C.-268° C. (dec).
EXAMPLE 4
6,8-Dichloro-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline
To a stirred solution of 2.5 g of 2-pyrrolidinone (Aldrich) in 100 mL of chloroform was added 4.5 g of phosphorus oxychloride at room temperature. The mixture was stirred for 2.5 hours at room temperature. To the above mixture was then added dropwise a solution of 5 g of 4,6-dichloroanthranilic acid (prepared from the corresponding isatine: T. Sandmeyer, Helv. Chim. Acta, 2:234 (1919), by oxidation with alkaline hydrogen peroxide, following the procedure described by Baker, et al, J. Org. Chem., 18:141 (1952) for the synthesis of 3-chloroanthranilic acid) in 50 mL of chloroform, containing 10 mL of triethylamine. Then the mixture was heated to reflux for 6 hours. Then the reaction mixture was carefully treated with 10 mL of water (exothermic!), followed by 10 g of solid anhydrous potassium carbonate. The mixture was filtered and the filtrate was concentrated in vacuo. The residue was chromatographed on silica gel using 10:1 chloroform:ethyl acetate as eluent. After concentration in vacuo of the appropriate fractions, there was obtained 1.5 g of crystalline 6,8-dichloro-2,3-dihydropyrrolo[2,1-b]quinazolin-9(1H)-one), which was used as such in the next step.
To a mechanically stirred solution of 1.5 g of the above 6,8-dichloro-2,3-dihydropyrrolo[2,1-b]quinazolin-9(1H)-one in 150 mL of glacial acetic acid at 60° C. was added 25 g of zinc dust. To this suspension was then added dropwise a solution of 35 mL of concentrated hydrochloric acid in 50 mL of glacial acetic acid in 20 minutes. After the addition was complete, the mixture was stirred for an additional 10 minutes. Then the unreacted zinc was filtered off (Caution!, Pyrophoric!), washed with 4×30 mL of glacial acetic acid and the filtrate was concentrated in vacuo. To the residue was added 80 mL of 20% aqueous sodium hydroxide and the product was extracted with tetrahydrofuran (3 times 150 mL). The organic extract was concentrated in vacuo and the residue was distributed between 100 mL of chloroform and 25 mL of water. The aqueous layer was extracted with 2×25 mL of chloroform. The combined extract was dried with anhydrous potassium carbonate, filtered, concentrated in vacuo, and flash chromatographed on silica gel, using 10:1 chloroform-methanol as eluent. The base was treated with 1 equivalent of 4N HCl in 50 mL absolute ethanol, concentrated in vacuo, redissolved in 50 mL absolute EtOH, concentrated, repeated again. Then the white solid was recrystallized from absolute EtOH-EtOAc, giving after drying in vacuo 0.8 g of 6,8-dichloro-1,2,3,9-tetrahydropyrrolo[2,1-b]-quinazoline hydrochloride in the form of white crystals, m.p. 305° C.-310° C. (dec.).
EXAMPLE 5
I. 1-Chlor-7,8,9,10-tetrahydroazepino[2,1-b]-quinazolin-12(6H)-one
18.01 g 6-chloroanthranilic acid suspended in 100 mL toluene was treated with 14 mL 1-aza-2-methoxy-1-cycloheptene (1) and refluxed with stirring under a Dean-Stark trap to remove the forming water and methanol for 1 hour. An exothermic reaction ensued, forming a two-layer mixture and foaming considerably. This gradually dissolved, giving a brown solution. Then 9 mL of (1) was added and the mixture was refluxed for 18 more hours. The toluene was removed in vacuo and excess of (1) was distilled out at 11 mmHg at 140° C. bath. The residue was chromatographed (6:1 chloroform-ethyl acetate) and recrystallized from hexane-ethyl acetate. The product, 1-chloro-tetrahydroazepino[2,1-b]quinazolin-12(6H)-one, was obtained as a white, crystalline solid, m.p. 128° C.-129° C.; yield 16.5 g.
II. 1-Chloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline
The reduction of 1-chloro-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-one to the 1-chloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline was performed in the same manner as described in Example 1 to 4.
EXAMPLE 6
I. 2-Chloro-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-one
Method A
5-Chloro-2-aminobenzoic acid was converted to 2-chloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazolin-12-one by the same procedure as described in Example 1.
Method B
2.5 g of 5-chloroisatoic anhydride (Aldrich) was mixed intimately with 1.1 g of epsilon-caprolactam (Aldrich). The mixture was then heated in an oil bath at 185° C.-190° C. The mixture melted with effervescence. The molten mass was stirred with heating until the gas evolution ceased. The cooled light greenish mass was then dissolved in 6:1 chloroform:ethyl acetate (10 mL) and chromatographed on silica gel, using the above solvent system as eluent, followed by recrystallization from hexaneethyl acetate.
II. 2-Chloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline
The reduction of 2-chloro-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-one to the 2-chloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline was performed in the same manner as described in Examples 1 to 9.
EXAMPLE 7
I. 4-Chloro-7,8,9,10-tetrahydroazepino[2,1,b]quinazolin-12(6H)-one
3-Chloro-2-aminobenzoic acid, obtained by catalytic hydrogenation of 3-chloro-2-nitrobenzoic acid over Ra-Ni in tetrahydrofuran was treated with 1-aza-2-methoxy-1-cycloheptene as outlined in Example 1. The crude mixture was composed mainly of the methylester of 3-chloro-2-aminobenzoic acid and a small amount of the desired compound. This crude mixture was added to a solution formed from one equivalent of ε-caprolactam and one equivalent of phosphorus oxychloride in 50 mL benzene, refluxed for 2 hours and then 50 mL 10% sodium hydroxide solution was added and the organic layer was separated, dried, and concentrated in vacuo. The residue was chromatographed by column chromatography on silica gel using 20:1 chloroform-ethyl acetate to give 9 g (53%) of the desired product as an off-white crystalline solid.
II. 4-Chloro-6,7,8,9,10,12-hexahydro[2,1-b]quinazoline
The reduction of 4-chloro-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-one to the 4-chloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline was performed in the same manner as described in Example 1 to 4, the m.p. of the hydrochloride salt is 272° C.-273° C. (dec).
EXAMPLE 8
I. 3-Methyl-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-one
25 g 2-bromo-4-methylbenzoic acid was treated with 150 mL of 28% aqueous ammonia, 50 g gaseous ammonia, 1 g CuSO 4 at 140° C. for 12 hours in an autoclave, then concentrated in vacuo, dissolved in a minimal amount of water, pH adjusted to 6 with 4N HCl. The precipitate was filtered, washed with ice cold water, and dried at 60° C. The residue was extracted with THF and concentrated in vacuo, giving a light brown crystalline solid. Yield of combined material: 14 g 4-methylanthranilic acid.
6.4 g of this acid was suspended with stirring in 100 mL toluene. 11 mL 1-Aza-2-methoxy-1-cycloheptene (1) (Aldrich) were added and the mixture was refluxed under a Dean-Stark trap for 12 hours. Then the toluene was removed by distillation in vacuo, followed by removal of excess (1) in vacuo (11 mm Hg) at 140° C. The dark brown residue crystallized. It was purified by column chromatography (6:1 chloroformethyl acetate) followed by recrystallization from hexane-ethyl acetate to give 7.1 g of pure 3-methyl-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-one as white, shiny crystals.
II. 3-Methyl-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-thione
9 g of 3-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazolin-12-one was treated with 15 g of Lawesson's reagent in toluene at reflux under nitrogen until the starting material was consumed, checked by TLC, using chloroform as eluent (24 hours). The mixture was concentrated in vacuo and chromatographed on silica gel, using chloroform as eluent. The bright yellow material was recrystallized from hexane-ethyl acetate.
III. 3-Methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline
Method A
The reduction of 3-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline-12-one to the 3-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline was performed in the same manner as described in Examples 1 to 4, hydrochloride salt, m.p. 260° C.-261° C. (dec).
Method B
3-Methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline
To a mechanically stirred solution of 5 g of 3-methyl-7,8,9,10-tetrahydroazepino[2,1-b]quinazoline-12(6H)-thione in 150 mL of boiling tetrahydrofuran was added in small portions wet Raney nickel (W-2, Davison Chemical, Chattanooga, Tenn.). The progress of the reaction was followed by TLC. When the reaction was complete, the mixture was filtered, solids on the filter were washed thoroughly with tetrahydrofuran and the filtrate was concentrated down. The rest of the workup was identical to that described in method A.
EXAMPLE 9
The following compounds are prepared by application of any of the procedures described in Examples 1 to 8:
1) 1-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
2) 2-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline, HCl salt, m.p. 244° C.-245° C.
3) 3-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline, HCl salt, m.p. 260° C.-261° C. (dec).
4) 4-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline, HCl salt, m.p. <280° C. (dec).
5) 1-chloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline, HCl salt, m.p. <280° C. (dec).
6) 2-chloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline, HCl salt, m.p. 277° C. (dec).
7) 3-chloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline, HCl salt, m.p. 270° C.-271° C. (dec).
8) 4-chloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline, HCl salt, m.p. 272° C.-273° C. (dec).
9) 1-fluoro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline, HCl salt, m.p. 271° C.-272° C. (dec).
10) 2-fluoro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline, HCl salt, m.p. 280° C.-282° C. (dec).
11) 3-fluoro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline, HCl salt, m.p. 295° C.-298° C. (dec).
12) 4-fluoro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline, HCl salt, m.p. 254° C.-256° C. (dec).
13) 1-(trifluoromethyl)-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
14) 2-(trifluoromethyl)-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
15) 3-(trifluoromethyl)-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
16) 4-(trifluoromethyl)-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
17) 1,2-dichloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline, HCl salt, m.p. 300° C.-303° C. (dec).
18) 1,3-dichloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline, HCl salt, m.p. 318° C.-319° C. (dec).
19) 1,4-dichloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline, HCl salt, m.p. 275° C.-276° C. (dec).
20) 2,3-dichloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline, HCl salt, m.p. 323° C.-325° C. (dec). 21) 2,4-dichloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline, HCl salt, m.p. 294° C.-295° C. (dec).
22) 3,4-dichloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline, HCl salt, m.p. 298° C.-300° C. (dec).
23) 2,3-dimethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline, HCl salt, m.p. 233° C.-235° C. (dec).
24) 2,4-dimethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
25) 3,4-dimethoxy-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
26) 1,2-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
27) 1,3-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
28) 1,4-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
29) 2,3-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
30) 2,4-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline, HCl salt, m.p. >266° C. (dec).
31) 3,4-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
32) 2-ethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline, HCl salt, m.p. 260° C.-261° C. (dec).
33) 2-(methylcarbamoyloxy)-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
34) 2-(heptylcarbamoyloxy)-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
35) 1-chloro-2-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
36) 1-chloro-3-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
37) 1-chloro-4-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
38) 2-chloro-1-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline, HCl salt, m.p. 288° C.-291° C. (dec).
39) 3-chloro-1-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
40) 4-chloro-1-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
41) 3-chloro-1-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
42) 3-chloro-2-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
43) 3-chloro-4-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
44) 4-chloro-1-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
45) 4-chloro-2-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline, HCl salt, m.p. 271° C.-273° C. (dec).
46) 4-chloro-3-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
47) 3-chloro-2,4-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
48) 1,3-dichloro-2-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
49) 1,3-dichloro-4-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
50) 1,3-dichloro-2,4-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline
51) 1-chloro-7,7-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
52) 3-chloro-7,7-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
53) 1-chloro-9,9-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
54) 3-chloro-9,9-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
55) 1,3-dichloro-7,7-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline
56) 1,3-dichloro-9,9-dimethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline
57) 1,3-dichloro-7,7,9,9-tetramethyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline, HCl salt, m.p. 320° C.-330° C. (dec).
58) 5-chloro-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
59) 6-chloro-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
60) 7-chloro-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
61) 8-chloro-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
62 ) 6,8-dichloro-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline, HCl salt, m.p. >305° C. (dec).
63) 5,7-dichloro-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
64) 5,8-dichloro-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
65) 2-phenyl-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
66) 6-chloro-2-phenyl-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
67) 6,8-dichloro-2-phenyl-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline,
68) 1-chloro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
69) 3-chloro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
70) 1,3-dichloro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline, HCl salt, m.p. >300° C. (dec
71 ) 8,8-diphenyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline, 72) 1-chloro-8,8-diphenyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
73) 3-chloro-8,8-diphenyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline, HCl salt, m.p. 302° C.-305° C. (dec).
74) 1-chloro-8,8-diphenyl-7-oxa-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
75) 3-chloro-8,8-diphenyl-7-oxa-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
76) 8,8-diphenyl-7-oxa-6,7,8,9-tetrahydro-11H-pyrido[2,1 -b]quinazoline,
77) 1,3-dichloro-8,8-diphenyl-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline, HCl salt, m.p. >307° C. (dec).
78) 1,3-dichloro-8,8-diphenyl-7-oxa-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazoline,
79) 8,8-diphenyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
80) 1-chloro-8,8-diphenyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
81) 3-chloro-8,8-diphenyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
82) 1,3-dichloro-8,8-diphenyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline
83) 3-chloro-6,7,8,9,10,12-hexahydro-6,9-methanoazepino[2,1-b]quinazoline,
84) 1,3-dichloro-6,7,8,9,10,12-hexahydro-6,9-methanoazepino[2,1-b]quinazoline;
85) 2,4-dichloro-6,7,8,9,10,12-hexahydro-6,9-methanoazepino[2,1-b]quinazoline;
86) 1,4-dichloro-6,7,8,9,10,12-hexahydro-6,9-methanoazepino[2,1-b]quinazoline;
87) 3-chloro-6,7,8,9,10,12-hexahydro-7,10-methanoazepino[2,1-b]quinazoline; (±) HCl salt, m.p. 264° C.-265° C. (dec).
88) 1,3-dichloro-6,7,8,9,10,12-hexahydro-7,10-methanoazepino[2,1-b]quinazoline
89) 2,4-dichloro-6,7,8,9,10,12-hexahydro-7,10-methanoazepino[2,1-b]quinazoline;
90) 1,4-dichloro-6,7,8,9,10,12-hexahydro-7,10-methanoazepino[2,1-b]quinazoline;
91) 3-chloro-6,7,8,9,10,12-hexahydro-6,10-methanoazepino[2,1-b]quinazoline;
92) 1,3-dichloro-6,7,8,9,10,12-hexahydro-6,10-methanoazepino[2,1-b]quinazoline; (±) HCl salt, m.p. 265° C.-268° C. (dec).
93) 2,4-dichloro-6,7,8,9,10,12-hexahydro-6,10-methanoazepino[2,1-b]quinazoline;
94) 1,4-dichloro-6,7,8,9,10,12-hexahydro-6,10-methanoazepino[2,1-b]quinazoline;
95) 1,3-dichloro-6,7,8,9-tetrahydro-11H-6,9-methanopyrido[2,1-b]quinazoline, (±) HCl salt, m.p. 261° C. (dec).
96) 1,3-dibromo-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
97) 3-bromo-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline,
98) 8,10-dichloro-1,2,5,11-tetrahydro-4H-[1,4]thiazepino[5,4-b]quinazoline,
99) 8,10-dichloro-1,2,5,11-tetrahydro-4H-[1,4]oxazepino[5,4-b]quinazoline,
100) 1,3-dichloro-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline, and
101) 1,3-dichloro-2-methyl-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazoline, HCl salt, m.p. 269° C.-272° C.
EXAMPLE 10
A mixture of 10 mmol of anthranilonitrile and 20 mmol of 1-aza-2-methoxy-1-cycloheptene (1) was heated under argon to 150° C. for 48 hours. Then the excess (1) was distilled out in vacuo (11 mm Hg) and the residue was chromatographed on silica gel. 4N HCl was added to a solution of the base in absolute ethanol to give the corresponding hydrochloride in over 90% yield. This procedure was used to synthesize the following derivatives using the appropriate substituted anthranilonitrile and iminoether.
a) 1-chloro-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-imine,
b) 2-chloro-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-imine,
c) 3-chloro-7,8,9,10 -tetrahydroazepino[2,1-b]quinazolin-12(6H)-imine, m.p. 128° C.-130° C.
d) 4-chloro-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-imine,
e) 1-methyl-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-imine,
f) 2-methyl-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-imine,
g) 3-methyl-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-imine,
h) 4-methyl-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-imine,
i) 1-fluoro-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-imine,
j) 2-fluoro-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-amine,
k) 3-fluoro-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-amine,
l) 4-fluoro-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-amine,
m) 1,3-dichloro-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-imine,
n) 1,2-dichloro-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-imine,
o) 2,3-dichloro-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-imine,
p) 1,4-dichloro-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-imine,
q) 2,4-dichloro-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-imine,
r) 3-chloro-1-methyl-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-imine
s) 1,3-dichloro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-imine,
t) 3-chloro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-imine,
u) 1-chloro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-imine,
v) 6,8-dichloro-2,3-dihydropyrrolo[2,1-b]quinazolin-9(1H)-imine,
w) 6-chloro-2,3-dihydropyrrolo[2,1-b]quinazolin-9(1H)-imine,
x) 8-chloro-2,3-dihydropyrrolo[2,1-b]quinazolin-9(1H)-imine, and
y) 3-(trifluoromethyl)-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)]imine, m.p. 101° C.-102° C.
EXAMPLE 11
1,3-dichloro-11H-pyrido[2,1-b]quinazolin-11-imine
Ten grams of 4,6-dichloro-2-nitroaniline (Aldrich Chemical Co.) was dissolved in 100 mL of anhydrous diethyl ether and cooled in an ice bath so that the internal temperature was between 5° C.-10° C. throughout the reaction. To this yellow solution was added 15 mL of 60% aqueous tetrafluoroboric acid (Aldrich Chemical Co.) and to this vigorously stirred solution was added in small portions 18 g of solid nitrosylsulfuric acid over a period of 4 hours. Then 10 mL of absolute ethanol was added and the white crystalline solid diazonium salt was filtered off with suction and washed twice with 60 mL diethyl ether and all of the solvent was removed by suction on the Buchner funnel. The filter cake was wetted immediately with 10 mL of saturated aqueous solution of sodium tetrafluoroborate. This paste was then added in small portions to a vigorously stirred mixture of 35 g of cuprous cyanide and 22 g of potassium cyanide in 300 mL of water. After the exothermic reaction subsided, the mixture was stirred 1 hour at room temperature and then briefly warmed to 60° C. Then it was filtered and the solids as well as the filtrate were extracted with chloroform 4×100 mL. The extract was dried with anhydrous magnesium sulfate and concentrated in vacuo to give 6.8 g of light brown solid 2-nitro-4,6-dichlorobenzonitrile, reasonably pure for the further transformation. Chromatography 4:1 chloroform/hexane followed by recrystallization from diethyl ether gave pure 4,6-dichloro-2-nitrobenzonitrile, with m.p. 102°-103° C. (Diazotization of 4,6-dichloro-2-nitroaniline in large excess of sulfuric acid, followed by reaction with CuCN/KCN in aqueous media by the methodology described by Atkinson, C. M. and Simpson, J. C. E., J. Chem. Soc., 1947:232, produced only very erratic results). The 4,6-dichloro-2-aminobenzonitrile was prepared by reduction of the above 2-nitro-4,6-dichlorobenzonitrile with stannous chloride using analogous conditions to those described by R. L. Mckee, M. K. Mckee, and R. W. Bost in J. Am. Chem. Soc. 69:940 (1947), and found to have m.p. 140°-141° C. Five grams of 4,6-dichloro-2-aminobenzonitrile and 6 mL of 2-chloropyridine in 20 mL of chlorobenzene were heated to boil until the reaction was judged complete by TLC (300:20:1 chloroform/methanol/28% aqueous ammonia). The excess solvent was removed in vacuo and the residue was distributed between 100 mL 10% aqueous sodium carbonate and chloroform. The chloroform layer was dried with anhydrous potassium carbonate, filtered, and the residue was column chromatographed on silica gel, using the above solvent as eluent. Concentration of the appropriate fractions yielded the 1,3-dichloro-11H-pyrido[2,1-b]quinazolin-11-imine as yellowish solid.
The above methodology is used to prepare the following compounds by heating the appropriately substituted 2-aminobenzonitrile derivative with the appropriately substituted 2-chloro-(or 2-fluoro- or 2-bromopyridine derivative) in the absence of a solvent or in the presence of solvent such as toluene, chlorobenzene, o-dichlorobenzene, anisole, 1,3-dimethoxybenzene, phenol and the like:
1-methyl-11H-pyrido[2,1-b]quinazolin-11-imine,
2-methyl-11H-pyrido[2,1-b]quinazolin-11-imine,
3-methyl-11H-pyrido[2,1-b]quinazolin-11-imine,
4-methyl-11H-pyrido[2,1-b]quinazolin-11-imine,
1-chloro-11H-pyrido[2,1-b]quinazolin-11-imine,
2-chloro-11H-pyrido[2,1-b]quinazolin-11-imine,
3-chloro-11H-pyrido[2,1-b]quinazolin-11-imine,
4-chloro-11H-pyrido[2,1-b]quinazolin-11-imine,
1-fluoro-11H-pyrido[2,1-b]quinazolin-11-imine,
2-fluoro-11H-pyrido[2,1-b]quinazolin-11-imine,
3-fluoro-11H-pyrido[2,1-b]quinazolin-11-imine,
4-fluoro-11H-pyrido[2,1-b]quinazolin-11-imine,
1-bromo-11H-pyrido[2,1-b]quinazolin-11 -imine,
2-bromo-11H-pyrido[2,1-b]quinazolin-11-imine,
3-bromo-11H-pyrido[2,1-b]quinazolin-11-imine,
4-bromo-11H-pyrido[2,1-b]quinazolin-11-imine,
1-(trifluoromethyl)-11H-pyrido[2,1-b]quinazolin-11-imine,
2-(trifluoromethyl)-11H-pyrido[2,1-b]quinazolin-11-imine,
3-(trifluoromethyl)-11H-pyrido[2,1-b]quinazolin-11-imine,
4-(trifluoromethyl)-11H-pyrido[2,1-b]quinazolin-11-imine,
1-(methylthio)-11H-pyrido[2,1-b]quinazolin-11-imine,
2-(methylthio)-11H-pyrido[2,1-b]quinazolin-11-imine,
3-(methylthio)-11H-pyrido[2,1-b]quinazolin-11-imine,
4-(methylthio)-11H-pyrido[2,1-b]quinazolin-11-imine,
1,2-dichloro-11H-pyrido[2,1-b]quinazolin-11-imine,
1,3-dichloro-11H-pyrido[2,1-b]quinazolin-11-imine,
1,4-dichloro-11H-pyrido[2,1-b]quinazolin-11-imine
2,3-dichloro-11H-pyrido[2,1-b]quinazolin-11-imine,
2,4-dichloro-11H-pyrido[2,1-b]quinazolin-11-imine,
3,4-dichloro-11H-pyrido[2,1-b]quinazolin-11-imine,
1,3-dimethoxy-11H-pyrido[2,1-b]quinazolin-11-imine,
2,3-dimethoxy-11H-pyrido[2,1-b]quinazolin-11-imine,
2,4-dimethoxy-11H-pyrido[2,1-b]quinazolin-11-imine,
3,4-dimethoxy-11H-pyrido[2,1-b]quinazolin-11-imine,
1,2-dimethyl-11H-pyrido[2,1-b]quinazolin-11-imine,
1,3-dimethyl-11H-pyrido[2,1-b]quinazolin-11-imine,
1,4-dimethyl-11H-pyrido[2,1-b]quinazolin-11-imine,
2,3-dimethyl-11H-pyrido[2,1-b]quinazolin-11-imine,
2,4-dimethyl-11H-pyrido[2,1-b]quinazolin-11-imine,
3,4-dimethyl-11H-pyrido[2,1-b]quinazolin-11-imine,
2-(methylcarbamoyloxy)-11H-pyrido[2,1-b]quinazolin-11-imine,
1-chloro-2-(methylcarbamoyloxy)-11H-pyrido[2,1-b]quinazolin-11-imine,
3-chloro-2-(methylcarbamoyloxy)-11H-pyrido[2,1-b]quinazolin-11-imine,
1-chloro-3-(methylcarbamoyloxy)-11H-pyrido[2,1-b]quinazolin-11-imine,
2-(heptylcarbamoyloxy)-11H-pyrido[2,1-b]quinazolin-11-imine,
3-(heptylcarbamoyloxy)-11H-pyrido[2,1-b]quinazolin-11-imine,
1-chloro-3-(heptylcarbamoyloxy)-11H-pyrido[2,1-b]quinazolin-11-imine,
3-chloro-2-(heptylcarbamoyloxy)-11H-pyrido[2,1-b]quinazolin-11-imine,
1,3-dichloro-2-(heptylcarbamoyloxy)-11H-pyrido[2,1-b]quinazolin-11-imine,
1-chloro-3-methyl-11H-pyrido[2,1-b]quinazolin-11-imine,
1-methyl-3-chloro-11H-pyrido[2,1-b]quinazolin-11-imine,
1,3-dichloro-11H-pyrido[2,1-b]quinazolin-11-methylamine,
1,3-dichloro-11H-pyrido[2,1-b]quinazolin-11-(2-phenylethyl)-imine,
1,3-difluoro-11H-pyrido[2,1-b]quinazolin-11-imine,
1-fluoro-3-bromo-11H-pyrido[2,1-b]quinazolin-11-imine,
1-fluoro-3-iodo-11H-pyrido[2,1-b]quinazolin-11-imine,
1-chloro-3-fluoro-11H-pyrido[2,1-b]quinazolin-11-imine,
1-chloro-3-bromo-11H-pyrido[2,1-b]quinazolin-11-imine,
1-chloro-3-iodo-11H-pyrido[2,1-b]quinazolin-11-imine,
1-bromo-3-fluoro-11H-pyrido[2,1-b]quinazolin-11-imine,
1-bromo-3-chloro-11H-pyrido[2,1-b]quinazolin-11-imine,
1-bromo-3-iodo-11H-pyrido[2,1-b]quinazolin-11-imine,
1,3-dibromo-11H-pyrido[2,1-b]quinazolin-11-imine,
1-iodo-3-fluoro-11H-pyrido[2,1-b]quinazolin-11-imine,
1-iodo-3-chloro-11H-pyrido[2,1-b]quinazolin-11-imine,
1-iodo-3-bromo-11H-pyrido[2,1-b]quinazolin-11-imine,
1,3-diiodo-11H-pyrido[2,1-b]quinazolin-11-imine,
1,3-dichloro-6-methyl-11H-pyrido[2,1-b]quinazolin-11-imine,
1,3-dichloro-7-methyl-11H-pyrido[2,1-b]quinazolin-11-imine,
1,3-dichloro-8-methyl-11H-pyrido[2,1-b]quinazolin-11-imine,
1,3-dichloro-9-methyl-11H-pyrido[2,1-b]quinazolin-11-imine,
1,3-dichloro-6-fluoro-11H-pyrido[2,1-b]quinazolin-11-imine,
1,3-dichloro-7-fluoro-11H-pyrido[2,1-b]quinazolin-11-imine,
1,3-dichloro-8-fluoro-11H-pyrido[2,1-b]quinazolin-11-imine,
1,3-dichloro-9-fluoro-11H-pyrido[2,1-b]quinazolin-11-imine,
1,3,6-trichloro-11H-pyrido[2,1-b]quinazolin-11-imine,
1,3,7-trichloro-11H-pyrido[2,1-b]quinazolin-11-imine,
1,3,8-trichloro-11H-pyrido[2,1-b]quinazolin-11-imine, or
1,3,9-trichloro-11H-pyrido[2,1-b]quinazolin-11-imine.
EXAMPLE 12
1,3-dichloro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline
To 30 g of 2-adamantanone (Aldrich Chem. Co.) in 100 mL of methanol was added 50 g of hydroxylamine hydrochloride and 92 g of sodium acetate trihydrate and the mixture was refluxed for 2 hours. The mixture was concentrated in vacuo, the residue was distributed between 250 of dichloromethane and 50 mL of water. The organic layer was separated, dried with magnesium sulfate and concentrated in vacuo to give 30 g of crude 2-adamantanone oxime. This was dissolved in 100 mL of chloroform and 135 g of PPE (polyphosphate ester, prepared by refluxing phosphorus pentoxide with diethyl ether in chloroform, as described by G. Schramm, H. Groetsch, and W. Pollmann, Angew. Chem., Internat. Ed., 1,1 (1962)) was added carefully. When the exothermic reaction ceased, the mixture was refluxed for 5 minutes. Then it was cool in ice, diluted with 500 mL of water and stirred overnight. The organic layer was separated, dried with magnesium sulfate and concentrated in vacuo to give 16.6 g of the crude lactam product. This was dissolved in 250 of chloroform and 11 mL of phosphorus oxychloride was added dropwise in 30 minutes. To this was then added a solution of 15 g of 4,6-dichloroanthranilic acid and 4 of triethylamine in 150 mL of chloroform in 25 minute at room temperature. Then the mixture was refluxed for 16 hours. Column chromatography using 50:1 to 25:1 chloroform:methanol on silica gel provided 16 g of 1,3-dichloro-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-one as white coarse crystals. This was then reduced with zinc and hydrochloric acid to the 1,3-dichloro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline by the same procedure as described in Example 2 to give after treatment with 1 equivalent of HCl and recrystallization from absolute alcohol/ethyl acetate 1,3-dichloro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline monohydrochloride as white crystalline solid, with m.p. 310° C. (dec.).
By the above procedure are prepared the following compounds:
1-methyl-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
2-methyl-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
3-methyl-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
4-methyl-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-chloro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
2-chloro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
3-chloro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
4-chloro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-fluoro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
3-fluoro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-bromo-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
2-bromo-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
3-bromo-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
4-bromo-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline
1-(trifluoromethyl)-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline, 2-(trifluoromethyl)-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
3-(trifluoromethyl)-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
4-(trifluoromethyl)-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1,2-dichloro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1,3-dichloro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1,4-dichloro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12 -dimethanoazonino[2,1-b]quinazoline,
2,3-dichloro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
2,4-dichloro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
3,4-dichloro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
2,3-dimethoxy-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
2-(methylcarbamoyloxy)-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-chloro-2-(methylcarbamoyloxy)-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
3-chloro-2-(methylcarbamoyloxy)-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-chloro-3-(methylcarbamoyloxy)-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
2-(heptylcarbamoyloxy)-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
3-(heptylcarbamoyloxy)-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-chloro-3-(heptylcarbamoyloxy)-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
3-chloro-2-(heptylcarbamoyloxy)-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1,3-dichloro-4-methyl-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1,3-dichloro-2,4-dimethyl-11H-pyrido[2,1-b]quinazoline,
1,3-difluoro-11H-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-fluoro-3-chloro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-fluoro-3-bromo-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-fluoro-3-iodo-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-chloro-3-fluoro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-chloro-3-bromo-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-chloro-3-iodo-11H-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-bromo-3-fluoro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-bromo-3-chloro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-bromo-3-iodo-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1,3-dibromo-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-iodo-3-fluoro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-iodo-3-chloro-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline,
1-iodo-3-bromo-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline, and
1,3-diiodo-6,7,8,9,10,11,12,14-octahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazoline.
EXAMPLE 13
1,3-dichloro-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine
To 30 g of 2-adamantanone (Aldrich Chem. Co.) in 100 mL of methanol was added 50 g of hydroxylamine hydrochloride and 92 g of sodium acetate trihydrate and the mixture was refluxed for 2 hours. The mixture was concentrated in vacuo, the residue was distributed between 250 mL of dichloromethane and 50 mL of water. The organic layer was separated, dried with magnesium sulfate and concentrated in vacuo to give 30 g of crude 2-adamantanone oxime. This was dissolved in 100 mL of chloroform and 135 g of PPE (polyphosphate ester, prepared by refluxing phosphorus pentoxide with diethyl ether in chloroform, as described by G. Schramm, H. Groetsch, and W. Pollmann, Angew. Chem., Internat. Ed., 1,1 (1962)) was added carefully. When the exothermic reaction ceased, the mixture was refluxed for 5 minute. Then it was cooled in ice, diluted with 500 mL of water and stirred overnight. The organic layer was separated, dried with magnesium sulfate and concentrated in vacuo to give 16.6 g of the crude lactam product. This was dissolved in 250 mL of chloroform and 11 mL of phosphorus oxychloride was added dropwise in 30 minutes. After stirring for additional 1 hour at room temperature, to this stirred mixture was added 25 mL of triethylamine and a solution of 16 g of 4,6-dichloro-2-aminobenzonitrile (4,6-dichloroanthranilonitrile) which was prepared by the methodology shown in Example 11.
The reaction mixture was stirred at room temperature for 12 hours, followed by reflux for 24 hours. Then the reaction mixture was treated with 500 mL of 15% aqueous potassium carbonate, the organic layer was separated, dried with anhydrous potassium carbonate and concentrated in vacuo. The dark brown residue was column chromatographed using 300:25:1 chloroform:methanol: 28% aqueous ammonia on silica gel. The corresponding fractions yielded the 1,3-dichloro-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine as a light tan solid.
By the above procedure are prepared the following compounds:
1-methyl-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
2-methyl-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
3-methyl-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
4-methyl-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
1-chloro-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
2-chloro-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
3-chloro-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
4-chloro-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
1-fluoro-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
3-fluoro-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
1-bromo-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
2-bromo-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
3-bromo-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
4-bromo-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
1-(trifluoromethyl)-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
2-(trifluoromethyl)-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
3-(trifluoromethyl)-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
4-(trifluoromethyl)-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
1,2-dichloro-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
1,3-dichloro-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
1,4-dichloro-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
2,3-dichloro-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
2,4-dichloro-6,7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
3,4-dichloro-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
2,3-dimethoxy-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
2-(methylcarbamoyloxy)-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
1-chloro-2-(methylcarbamoyloxy)-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
3-chloro-2-(methylcarbamoyloxy)-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
1-chloro-3-(methylcarbamoyloxy)-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
2-(heptylcarbamoyloxy)-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
3-(heptylcarbamoyloxy)-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
1-chloro-3-(heptylcarbamoyloxy)-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
3-chloro-2-(heptylcarbamoyloxy)-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
1,3-dichloro-4-methyl-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
1,3-difluoro-11H-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
1-fluoro-3-chloro-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
1-fluoro-3-bromo-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
1-fluoro-3-iodo-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
1-chloro-3-fluoro-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
1-chloro-3-bromo-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
1-chloro-3-iodo-11H-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
1-bromo-3-fluoro-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
1-bromo-3-chloro-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
1-bromo-3-iodo-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
1,3-dibromo-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
1-iodo-3-fluoro-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine,
1-iodo-3-chloro-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino(2,1-b]quinazolin-14(6H)-imine,
1-iodo-3-bromo-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)-imine and,
1,3-diiodo-7,8,9,10,11,12-hexahydro-6,10:8,12-dimethanoazonino[2,1-b]quinazolin-14(6H)]imine.
EXAMPLE 14
1,3-dichloro-11H-pyrido[2,1-b]quinazoline
Twenty-five grams of 4,6-dichloroanthranilic acid was added portionwise to 250 mL of methanol, saturated with anhydrous HCl at 0° C. with vigorous stirring. The mixture was then stirred at room temperature for 24 hours. Then the mixture was stirred at 60° C. for 12 hours. Then the excess solvent was removed in vacuo into a cold trap and the residue was distributed between 100 mL of chloroform and 250 mL of 10% aqueous sodium carbonate. The organic layer was separated and dried with anhydrous magnesium sulfate. After concentration in vacuo the residue was dissolved in 150 mL of dry THF and added dropwise into a solution of 20 g of lithium aluminum hydride in 500 mL of anhydrous THF in 30 minutes at 10° C. Then the mixture was stirred at room temperature for I hour and then cooled in ice-salt bath and decomposed with saturated aqueous potassium carbonate. The precipitate was filtered off and the filtrate was dried with anhydrous magnesium sulfate, filtered and concentrated in vacuo. The residue was added portionwise into concentrated hydrochloric acid through which a gentle stream of hydrogen chloride was passed. The mixture was warmed to 60° C. At the end of the reaction the solid that formed was collected and dried in a stream of nitrogen.
Five grams of the above solid 4,6-dichloro-2-aminobenzyl chloride hydrochloride was heated with 10 mL of 2-chloropyridine in 25 mL of chlorobenzene. The reaction was followed by TLC (300:20:1 chloroform/methanol/28% aqueous ammonia). When the reaction was complete, the reaction mixture was concentrated in vacuo (cold trap). The residue was basified with saturated aqueous potassium carbonate and distributed between 50 mL of chloroform and 50 mL of water. The chloroform layer was separated, dried with anhydrous potassium carbonate and concentrated in vacuo. The brown residue was chromatographed using the above solvent system and the appropriate fractions were concentrated in vacuo to give a yellow solid. This was treated with one equivalent of 4N hydrochloric acid and coevaporated with 50 mL of absolute ethanol. The residue was recrystallized from absolute ethanol-ethyl acetate mixture to give the hydrochloride of 1,3-dichloro-11H-pyrido[2,1-b]quinazoline.
The above methodology is used to prepare the following compounds by heating the appropriately substituted 2-aminobenzyl chloride derivative hydrochloride with the appropriately substituted 2-chloro- (or 2-fluoro-or 2-bromopyridine derivative) in the absence of a solvent or in the presence of solvent such as toluene, chlorobenzene, dichlorobenzene, anisole, 1,3-dimethoxybenzene, phenol and the like.
1-methyl-11H-pyrido[2,1-b]quinazoline,
2-methyl-11H-pyrido[2,1-b]quinazoline,
3-methyl-11H-pyrido[2,1-b]quinazoline,
4-methyl-11H-pyrido[2,1-b]quinazoline,
1-chloro-11H-pyrido[2,1-b]quinazoline,
2-chloro-11H-pyrido[2,1-b]quinazoline,
3-chloro-11H-pyrido[2,1-b]quinazoline,
4-chloro-11H-pyrido[2,1-b]quinazoline,
1-fluoro-11H-pyrido[2,1-b]quinazoline,
2-fluoro-11H-pyrido(2,1-b]quinazoline,
3-fluoro-11H-pyrido[2,1-b]quinazoline,
4-fluoro-11H-pyrido[2,1-b]quinazoline,
1-bromo-11H-pyrido[2,1-b]quinazoline,
2-bromo-11H-pyrido[2,1-b]quinazoline,
3-bromo-11H-pyrido[2,1-b]quinazoline,
4-bromo-11H-pyrido[2,1-b]quinazoline,
1-(trifluoromethyl)-11H-pyrido[2,1-b]quinazoline,
2-(trifluoromethyl)-11H-pyrido[2,1-b]quinazoline,
3-(trifluoromethyl)-11H-pyrido[2,1-b]quinazoline,
4-(trifluoromethyl)-11H-pyrido[2,1-b]quinazoline,
1-(methylthio)-11H-pyrido[2,1-b]quinazoline,
2-(methylthio)-11H-pyrido[2,1-b]quinazoline,
3-(methylthio)-11H-pyrido[2,1-b]quinazoline,
4-(methylthio)-11H-pyrido[2,1-b]quinazoline,
1,2-dichloro-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-11H-pyrido[2,1-b]quinazoline,
1,4-dichloro-11H-pyrido[2,1-b]quinazoline,
2,3-dichloro-11H-pyrido[2,1-b]quinazoline,
2,4-dichloro-11H-pyrido[2,1-b]quinazoline,
3,4-dichloro-11H-pyrido[2,1-b]quinazoline,
1,3-dimethoxy-11H-pyrido[2,1-b]quinazoline,
2,3-dimethoxy-11H-pyrido[2,1-b]quinazoline,
2,4-dimethoxy-11H-pyrido[2,1-b]quinazoline,
3,4-dimethoxy-11H-pyrido[2,1-b]quinazoline,
1,2-dimethyl-11H-pyrido[2,1-b]quinazoline,
1,3-dimethyl-11H-pyrido[2,1-b]quinazoline,
1,4-dimethyl-11H-pyrido[2,1-b]quinazoline,
2,3-dimethyl-11H-pyrido[2,1-b]quinazoline,
2,4-dimethyl-11H-pyrido[2,1-b]quinazoline,
3,4-dimethyl-11H-pyrido[2,1-b]quinazoline,
2-(methylcarbamoyloxy)-11H-pyrido[2,1-b]quinazoline,
1-chloro-2-(methylcarbamoyloxy)-11H-pyrido(2,1-b]quinazoline,
3-chloro-2-(methylcarbamoyloxy)-11H-pyrido[2,1-b]quinazoline,
1-chloro-3-(methylcarbamoyloxy)-11H-pyrido[2,1-b]quinazoline,
2-(heptylcarbamoyloxy)-11H-pyrido[2,1-b]quinazoline,
3-(heptylcarbamoyloxy)-11H-pyrido[2,1-b]quinazoline,
1-chloro-3-(heptylcarbamoyloxy)-11H-pyrido[2,1-b]quinazoline,
3-chloro-2-(heptylcarbamoyloxy)-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-2-(heptylcarbamoyloxy)-11H-pyrido[2,1-b]quinazoline,
1-chloro-2-methyl-1H-pyrido[2,1-b]quinazoline,
1-chloro-3-methyl-11H-pyrido[2,1-b]quinazoline,
1-chloro-4-methyl-11H-pyrido[2,1-b]quinazoline,
2-chloro-1-methyl-11H-pyrido[2,1-b]quinazoline,
3-chloro-1-methyl-11H-pyrido[2,1-b]quinazoline,
4-chloro-1-methyl-11H-pyrido[2,1-b]quinazoline,
3-chloro-1-methyl-11H-pyrido[2,1-b]quinazoline,
3-chloro-2-methyl-11H-pyrido[2,1-b]quinazoline,
3-chloro-4-methyl-11H-pyrido(2,1-b]quinazoline,
4-chloro-1-methyl-11H-pyrido[2,1-b]quinazoline,
4-chloro-2-methyl-11H-pyrido[2,1-b]quinazoline,
1-methyl-3-chloro-11H-pyrido[2,1-b]quinazoline,
3-chloro-1,4-dimethyl-11H-pyrido[2,1-b]quinazoline,
1-chloro-3-methyl-11H-pyrido[2,1-b]quinazoline,
1-methyl-3-chloro-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-2-methyl-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-4-methyl-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-2,4-dimethyl-11H-pyrido[2,1-b]quinazoline,
1-chloro-11,11-dimethyl-11H-pyrido[2,1-b]quinazoline,
3-chloro-11,11-dimethyl-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-11-methyl-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-11,11-dimethyl-11H-pyrido[2,1-b]quinazoline,
3-chloro-11-methylene-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-11-isopropylidene-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-11-methylene-11H-pyrido[2,1-b]quinazoline,
1,3-difluoro-11H-pyrido[2,1-b]quinazoline,
1-fluoro-3-bromo-11H-pyrido[2,1-b]quinazoline,
1-fluoro-3-iodo-11H-pyrido[2,1-b]quinazoline,
1-chloro-3-fluoro-11H-pyrido[2,1-b]quinazoline,
1-chloro-3-bromo-11H-pyrido[2,1-b]quinazoline,
1-chloro-3-iodo-11H-pyrido[2,1-b]quinazoline,
1-bromo-3-fluoro-11H-pyrido[2,1-b]quinazoline,
1-bromo-3-chloro-11H-pyrido[2,1-b]quinazoline,
1-bromo-3-iodo-11H-pyrido[2,1-b]quinazoline,
1,3-dibromo-11H-pyrido[2,1-b]quinazoline,
1-iodo-3-fluoro-11H-pyrido[2,1-b]quinazoline,
1-iodo-3-chloro-11H-pyrido[2,1-b]quinazoline,
1-iodo-3-bromo-11H-pyrido[2,1-b]quinazoline,
1,3-diiodo-11H-pyrido[2,1-b]quinazoline,
1-bromo-3-fluoro-11H-pyrido[2,1-b]quinazoline,
1-bromo-3-chloro-11H-pyrido[2,1-b]quinazoline,
1-bromo-3-iodo-11H-pyrido[2,1-b]quinazoline,
1,3-dibromo-11H-pyrido[2,1-b]quinazoline,
1-iodo-3-fluoro-11H-pyrido[2,1-b]quinazoline,
1-iodo-3-chloro-11H-pyrido[2,1-b]quinazoline,
1-iodo-3-bromo-11H-pyrido[2,1-b]quinazoline,
1,3-diiodo-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-6-methyl-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-7-methyl-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-8-methyl-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-9-methyl-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-6-fluoro-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-7-fluoro-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-8-fluoro-11H-pyrido[2,1-b]quinazoline,
1,3-dichloro-9-fluoro-11H-pyrido[2,1-b]quinazoline,
1,3,6-trichloro-11H-pyrido[2,1-b]quinazoline,
1,3,7-trichloro-11H-pyrido[2,1-b]quinazoline,
1,3,8-trichloro-11H-pyrido[2,1-b]quinazoline, and
1,3,9-trichloro-11H-pyrido[2,1-b]quinazoline.
EXAMPLE 15
(±)-1,3-dichloro-6,9-dihydro-11H-6,9-methanopyrido[2,1-b]quinazoline hydrochloride
Two grams of 4,6-dichloroanthranilic acid was treated with 6 mL SOCl 2 in 25 mL benzene and heated to boil for 30 minutes. Then all volatiles were distilled out in vacuo. The light brownish residue was dissolved in 25 mL CCl 4 and cooled in ice bath. A solution of 1 g of (±)-2-azabicyclo[2.2.1]hept-5-en-3-one (Aldrich Chem. Co.) in 20 mL ethanol-free chloroform was added dropwise over a 2-hour period, then the mixture was stirred at room temperature for hours. Then the reaction mixture was refluxed briefly and concentrated in vacuo. The brown residue was chromatographed on silica gel using chloroformethyl acetate 12:1 as eluent. The corresponding fractions were concentrated in vacuo to provide the (±)-1,3-dichloro-11H-6,9-methanopyrido[2,1-b]quinazolin-11-one. This was dissolved in 25 mL glacial acetic acid at 50° C. Ten grams of zinc dust was added and the mixture was mechanically stirred. Then concentrated HCl was added dropwise (approximately 10 mL) in 7 minutes and the progress of the reaction was monitored by TLC. After 10 minutes, the excess of clumped zinc (pyrophoric!) was filtered off and the filtrate was diluted with 200 mL CHCl 3 and basified carefully with 20% NaOH (ice cooling). After filtration, the organic layer was separated, dried with K 2 CO 3 , and concentrated in vacuo. The residue was chromatographed using 300:25:1 CHCl 3 :MeOH: 28% aqueous ammonia. The corresponding fractions were concentrated in vacuo, dissolved in 50 mL absolute ethanol, and treated with equivalent amount of 4N HCl. This was concentrated in vacuo and dried by twice coevaporating with 50 mL absolute EtOH. The residue was recrystallized from absolute ethyl alcohol-ethyl acetate to give white crystalline hydrochloride salt.
The (+) and (-) enantiomers are prepared by the same methodology from the commercially available enantiomeric lactams.
EXAMPLE 16
1,3-Dichloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazolin-12-ol
Method A:
To a solution of 2 g of 1,3-dichloro-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-one in 100 mL of glacial acetic acid at 50° C. was added an intimately mixed mixture of 15 g zinc dust and 15 g silica gel (column chromatography grade). To this mechanically stirred suspension was added dropwise concentrated hydrochloric acid, while the progress of the reaction was followed by TLC (20:1 CHCl 3 :MeOH, basified aliquots, extracted into chloroform). When the reaction was essentially complete, excess zinc was filtered off (pyrophoric!) the filtrate was concentrated in vacuo, basified, extracted with chloroform, and the crude extract was chromatographed using 20:1 chloroform:methanol as eluent on a silica gel column. The corresponding fractions after concentration in vacuo gave the 1,3-dichloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazolin-12-ol as an off-white crystalline solid.
Method B:
To a solution of 1 g of 1,3-dichloro-7,8,9,10-tetrahydroazepino[2,1-b]quinazolin-12(6H)-one in 30 mL of hot triethylsilane was added 5 m of trifluoroacetic acid and the mixture was stirred at 100° C.-110° C. under nitrogen. More triethylsilane and trifluoroacetic acid were added until the reaction was substantially complete as evidenced by TLC (basified aliquot extracted into CHCl 3 ). Then all volatiles were removed in vacuo and the residue was basified, extracted into chloroform, and chromatographed using 20:1 chloroform:methanol on a silica gel column. Concentration of the corresponding fractions provided the desired 1,3-dichloro-6,7,8,9,10,12-hexahydroazepino[2,1-b]quinazolin-12-ol as a greyish-white solid. | A method of treating cognitive deficiencies is described by administering a quinazoline derivative of the general formula ##STR1## wherein A represents ##STR2## in which n is 1-10, P is a bond or (CH 2 ) m in which m is 0-10, and M is ═O, ═S, ═NR, ═CRR', ##STR3## novel compounds of the above are also described as well as methods of manufacture and pharmaceutical compositions. | 2 |
BACKGROUND OF THE INVENTION
The invention relates to a circuit layout for signal amplification of the type stated in the preamble of claim 1.
Linear operation amplifiers with high amplification must be capacitively coupled if the signal D.C. voltage is not defined or is so great that the amplifier limits on one side. With capacitive coupling, the centre voltage, which is superposed by the A.C. voltage, is applied to the amplifier input. The transmission of the A.C. voltage is influenced by the time constant τ=R e ·C (where C=coupling capacity, R e= resistance value of the input resistance of the amplifier). To minimize signal distortions, the time constant must exceed the largest signal period. On the other hand, in order for the amplifier to return to its set operating point in finite time in the event of a high-amplitude interference signal, the time constant cannot be of arbitrary size.
Particularly in cases where the signal voltage is proportional to a light intensity, the result is very high dynamics and interference signals which may exceed the useful signal by a factor of 1000, for example. Single interference signals of this type lead to a high displacement current flowing in the coupling capacitor for a short period as a consequence of the finite time constant, with the result that the amplifier is overmodulated with opposite polarity following the interfering pulse until the capacitor has been reloaded. Interference of this nature may occur periodically during image transmission. In this case, the amplifier is driven to its limit on both sides, depending on the amplitude and the duty cycle of the interference signals. Information contained in the low-level signal is completely lost thereyb, as no suitable rest operating point is set at the amplifier input.
To reduce the influence of large interference signals, D.C. amplifiers, for example logarithmic amplifiers, with diodes in the negative feedback branch are frequently used. This reduces the amplification for high-level signals, but does not eliminate the shift in the operating point caused by high-level signal pulses in the case of capacitive signal coupling. This greatly reduces the amplification for low-level signals following an interference pulse until the operating point has reset.
SUMMARY OF THE INVENTION
The object underlying the invention is to provide a circuit which permits an ungrounded linear amplification of low-level signals without involving a displacement of the operating point from the set operating point as a result of interfering high-level signals which are not to be transmitted in linear mode. In particular, a circuit layout is to be provided that is monolithically integratable in bipolar design onto as small a chip area as possible.
The object is attained in a circuit layout of the type stated in the preamble of claim 1 by the features stated in the characterizing clause of claim 1.
Due to the fact that the input resistance of the differential amplifier gest high-impedance when a preset signal level is exceeded, the coupling capacitor is not reloaded, with the result that the circuit layout shows the original linear low-level signal amplification immediately after overmodulation is eliminated.
Further advantageous embodiments of the invention can be found in the sub-claims. In the embodiment of the invention according to claim 2, a preset maximum voltage appears at the amplifier output when the circuit layout is overmodulated to indicate that a high-level signal is present. Furthermore, the output signal is advantageously transient-free. In the embodiment of the invention according to claim 3, the input voltage range to be linearly amplified can easily be set in dependence upon the selected signal amplification. By means of an emitter follower connected upstream according to claim 4, the input resistance of the circuit layout not only increases, but it is also independent of the amplification setting. The embodiment of the invention according to claim 5 serves to compensate the input static current of the amplifier which is drawn from the coupling capacitor for the duration of the high-level signal.
The invention will now be described in greater detail, with reference to embodiments and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a circuit layout according to the invention with a differential amplifier;
FIG. 2 shows a circuit layout according to the invention with a second switchable differential amplifier;
FIG. 3 shows a circuit diagram of the comparator with preamplifier;
FIG. 4 shows a circuit diagram of the amplifier input with emitter follower and current mirror for base current compensation.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows in the simplest form a circuit layout for signal amplification by means of a differential amplifier DV1 comprising transistors 1 and 2 and collector resistors 3 and 4, and emitter current source 7. Signal coupling is effected via input E and capacitor 9. Input E1 of the differential amplifier, to which capacitor 9 is connected, is also connected via a resistor 5, and the other input via a resistor 6, jointly via an electronic switch designed in the embodiment as transistor 8, to reference potential M.
Transistor 8 provided as an electronic switch is controllable by a comparator 12. A reference voltage source 13 is connected to one input of the comparator, and an RC element to the other input, said element comprising resistor 11 and capacitor 10, where the capacitor is connected between one input of the comparator and the input of the circuit layout In normal operation, transistor 8 is conductive and the input resistance of the circuit layout measured between terminals E1 and M is determined by resistors 5 and 6, which meet the condition
R.sub.8 <<(R.sub.5, R.sub.6)<<R.sub.id
where R 8 is the interconnecting resistor of transistor 8 and ##EQU1## is the differential input resistance of the differential amplifier without resistors 5 and 6. Furthermore, R B is the internal base resistance of a transistor 1 or 2, U T the temperature voltage of a transistor (26 mV at 25° C.), and I 7 the current of emitter current source 7.
Capacitor 9 is for ungrounded signal coupling. The input signal is coupled via a second capacitor 10 into a level detector designed as comparator 12.
The time constants R 11 ·C 10 and R 5 ·C 9 are expediently of identical size and so selected that they are approximately the same size as the signal period of the useful signal with the lowest frequency to be transmitted. For rapid operating point setting to the set operating point, they should not be selected unduly large.
In the case of high-level signal interference, for example, with signals 40 dB above the useful signal, comparator 12 blocks transistor 8. Since resistors R 5 and R 6 are very much smaller than the differential input resistance of transistors 1 and 2, the differential amplifier stage is subjected to common-mode triggering, with the input resistance of the differential amplifier between terminals E1 and the reference line M assuming the high value
R.sub.E1M =β·R.sub.7 <<R.sub.5
on account of the high differential resistance R 7 of current source 7. The result is a very large time constant C 9 ·R E1M , which prevents a displacement current in capacitor C 9 during high-level signal modulation.
If the declining edge of the high-level signal falls below the comparator threshold, transistor 8 becomes conductive again, and the differential amplifier stage is again operated in linear mode without operating point displacement or capacitance reloading of the capacitor 9. The comparator threshold U 13 at input 13 of comparator 12 is best set in such a way that the time constant is switched over shortly before the input signal drives the differential amplifier output A to its limit.
The differential amplifier stage DV1 is best dimensioned, for operating time reasons, so that transistors 1 and 2 are not driven into saturation by the amplitude of an anticipated maximum high-level signal.
The circuit layout is thus in a position to amplify low-level signals in linear mode without operating point displacement by high-level signals. The output signal U AM at output A of the amplifier, however, drops, when a high-level signal is present and when the maximum voltage has been reached, to the output voltage corresponding to the common-mode amplification
v=R.sub.3 /(2·R.sub.7)
which furthermore leads to transients.
As a rule, the information "high-level signals" is required at the output of the amplifier, so that it is best for a preset maximum level to be set at the amplifier output for the duration of a high-level signal applied at the input. This is achieved in the embodiment of the circuit layout according to FIG. 2. In this case, a second differential amplifier DV2 having two transistors 15 and 16 is connected to the collectors of transistors 1 and 2. For the two transistors, an emitter current source 20 is provided which is connectable in a first switching condition to the interconnected emitters of the two transistors 15 and 16, and in a second switching condition to output A' of the second differential amplifier DV2, via a change switch controlled by comparator 12 via input E2', said switch comprising in the embodiment the two transistors 18 and 19.
A resistor 21 between the line conducting the operating voltage +U B and the connection point of the two collector resistors 3 and 4 of the first differential amplifier serves, in a manner known per se, to shift the potential of the collector voltage of transistors 1 and 2 and thereby the base voltages of transistors 15 and 16.
In the normal case, i.e. with a low-level signal, transistors 8 and 18 are conductive while transistor 19 is blocked. The current of current source 20 then flows through transistors 15 and 16 of the second differential amplifier DV2 and effects a linear amplification of the second differential amplifier too. The input resistance R E1M between input terminal E1 and reference line M is determined by resistor 5.
An overmodulation high-level signal first drives the amplifier output A' almost to its limit. When the input voltage U E1M associated with the limit is reached, transistors 8 and 18 are blocked and 19 is opened. The entire current of current source 20 then flows through resistor 17 in the collector of transistor 16 and maintains the output voltage U AMmax , corresponding to the limit condition, at a constant level until switchover to the linear operating condition takes place again once the high-level signal has disappeared.
The amplifier input is, as already described, high-impedance for the duration of the high-level signal. The amplifier output signal does not, however, show the input signal multiplied by the common-mode amplification, but the maximum output level preset by the operating voltages +U B , -U B , current source 20 and resistor 17. When transistors 8 and 18 are triggered simultaneously by comparator 12, the output signal U AM is advantageously transient-free.
If, as shown in FIGS. 1 and 2, there are no resistors in series with the emitters of transistors 1, 2, 15 and 16, amplification of the circuit arrangement can be set using controllable current sources 7 and 20. This, however, causes a change in the input voltage value at which the limit occurs at amplifier output A'. Since comparator 12 switches over when the constant comparator threshold U 13 is exceeded, said threshold being selected identical to the maximum permissible input voltage, the dynamics for linear transmission are only optimum when the signal amplifier is discretely amplified.
When the amplification of the signal amplifier is set low, switchover to high-level signal takes place at the input signal levels which could still be transmitted in linear mode. This leads to a voltage jump at output A' at every switchover. On the other hand, if the signal amplifier has a high amplification setting, the signal amplifier can be driven to its limit even with a low-level signal without the desired switchover taking place.
These drawbacks are avoided with the circuit layout according to FIG. 3 by adapting the comparator threshold U 13 to the appropriate maximum input voltage U E1max =U AMmax /V permissible and thus to the amplification of the signal amplifier.
In FIG. 3, the amplifier input is shown between input terminal E and terminals E1 and E2. Elements the same as in FIG. 1 are numbered identically. As can be seen, a preamplifier 30 is connected upstream of the signal input of comparator 12 and a preamplifier 31 upstream of the reference input of comparator 12. Both preamplifiers 30 and 31 are controllable in the same way as the signal amplifier (DV1 with DV2) as regards amplification. For this purpose, their control inputs are connected up and are controllable by a settable control voltage U 32 via a common line 32 connected to control input 27 of current sources 7 and 20 (FIG. 2).
To ensure that preamplifiers 30 and 31 have as identical as possible an amplification and as identical as possible an amplification development during amplification control, the preamplifiers are best constructed in the same way as the signal amplifier, but with resistors 5 and 6 of differential amplifier DV1 being connected directly to reference potential M and with the controllable current source 20 being connected directly to the emitters of transistors 15 and 16, omitting transistors 18 and 19 of differential amplifier DV2. In the case of preamplifier 30, resistance 11 at its input (FIG. 3) then corresponds, for example, to resistance 5 of differential amplifier DV1 in FIG. 2.
Preamplifier 31 has the task of adapting the reference voltage and thus the switchover point to the respective maximum output voltage U AM of the signal amplifier, said reference voltage depending on the amplification setting, the operating voltage and the ambient temperature; for example, the current of current source 20 of the second differential amplifier DV2 is increased when a greater amplification is set. In the case of signal amplification cutout at a high-level signal and thereby conducting transistor 19, the voltage drop is then greater due to the higher current of current source 20 at resistor 17, and the voltage U AM thereby lower. Consequently, the reference voltage for comparator 12 must be lowered when a switchover is made in order to avoid transients. That means that preamplifier 31 must be switched such that its output (D.C.) voltage decreases when a higher amplification is set.
The input of amplifier 31 is at a constant potential designated +U in the Figure. The amount of constant input voltage +U is selected so that output 13 of preamplifier 31 is kept in the limit condition regardless of the amplification setting. That means that the transistor corresponding to the differential amplifier DV2 in preamplifier 31 is always set to be conductive.
In addition, the output voltage of preamplifier 31 is slightly smaller (approx. 5-10%) than the maximum output voltage of preamplifier 30 and thus of the signal amplifier.
The input voltage range of the signal amplifier which is to undergo linear amplification can be advantageously set using the amplification setting via voltage U 32 . The circuit layout according to FIG. 2, supplemented with the circuit according to FIG. 3, then operates, independently of the amplification set via voltage U 32 and independently of the operating temperature and the supply voltage, in linear mode until the maximum output level is reached at output A', and, when this level has been reached, switches over the input time constant of the signal amplifier.
In FIG. 4, an advantageous embodiment is shown of the first differential amplifier stage DV1 containing transistors 1 and 2. An emitter follower 22 and 23 is connected upstream of transistors 1 and 2, respectively, and resistors 5 and 6 to the respective base electrodes of the emitter followers. The input resistance of the first differential amplifier is thereby advantageously increased, regardless of the amplification and negligibly in comparison with resistors 5 and 6. The emitter followers also reduce the input static current of the amplifier. Furthermore, they reduce, when transistor 8 is blocked, the input static current of transistors 1 and 2, which would cause an undesired reloading process in the capacitor 9, and thus an operating point shift, if a high-level signal were to be applied for any length of time.
Furthermore, FIG. 4 shows that an additional transistor 24 and 25, respectively, is connected in the collector line of each emitter follower 22 and 23, the base connections of said transistors being connected to a current mirror circuit 26 and 27, respectively, connected to the power supply line conducting +U B voltage. The collector of current mirror circuit 26 and 27 respectively, carrying the mirrored current, is connected to the base of the corresponding emitter follower 22 and 23 respectively. Since, for example,transistor 24 has the same base current as transistor 22, its base current mirrored above the current mirror 26 effects compensation of the base current of transistor 22, so that the set operating point is subsequently reached practically without deviation even after lengthy blocking of transistor 8 by a high-level signal. | In a circuit layout for signal amplification with the aid of a differential amplifier and signal coupling via a first capacitor, it is proposed, in order to prevent unacceptable operating point displacements into the non-linear area of the amplifier layout in the event of temporarily interfering high-level signals, that one input of the differential amplifier connected to the signal source via the first capacitor be connected via a first resistor, and the other input via a second resistor, jointly via an electronic switch controllable by a comparator, to reference potential. A reference voltage source is connected to one input of the comparator, and the signal source to the other input of the comparator via an RC element, whose time constant is of the same order of magnitude as the time constant formed by the first capacitor and the first resistor. | 7 |
FIELD OF THE INVENTION
The present invention relates to the field of software development, and to large scale computer programs exhibiting complexity. It relates particularly to determining the possibility of adverse effects in other components of the program arising from code changes elsewhere in the program.
BACKGROUND
Any large software product/program is most usually developed by large, numerous and possibly geographically distributed teams of programmers. This presents several challenges. One of the challenges is to ensure that code changes introduced in one component (or part) do not affect the correct execution of other dependent components (or parts). The dependency of such components can be due to referencing a type, or due to consuming data produced by that type. Typically, the dependency between the various components is not known accurately, due to incomplete specifications or due to the specification not being up-to-date.
One approach to this problem is manually trying to identify adverse affects (leading to errors), but this is quite impractical for complex software.
U.S. Pat. No. 5,694,540, issued to Humelsine et al on Dec. 2, 1997, teaches a set of tests to run on a computer program as a regression test that provides an approximation to the level of testing that is achieved by full regression. A modification request is associated with a test case and the files that change due to the modification are recorded. The test cases associated with the files that are modified by the modification are run.
US Patent Publication No. 2003/0018950A1, in the name Sparks et al, published on Jan. 23, 2003, describes an approach where classes are dynamically reloaded if a code change is detected. A developer can see the result of a change after a build/package step.
These known methods provide only a partial solution to predicting adverse effects. There thus remains a need for an automated approach to more completely detecting adverse effects in other program components resulting from code changes.
SUMMARY
The invention provides a method for determining the possibility of adverse effect arising from a code change in a computer program. The method identifies important classes within a computer program. The method determines, directly and indirectly, dependent classes of the important classes. The important classes comprise superclasses of the directly and indirectly dependent classes. The method associates test cases with the important classes and with the directly and indirectly dependent classes. For a given code change to a first important class, the method runs all test cases associated with the first important class and associated with dependent classes of the first important class, and indicates the possibility of an adverse effect if any run test case fails.
DESCRIPTION OF DRAWINGS
FIG. 1 is a diagram illustrating class dependencies.
FIG. 2 is a flow diagram of an initialization process.
FIG. 3 is a flow diagram of determining the possibility of adverse effects from code changes.
FIG. 4 shows the inheritance structure of a set of classes.
FIG. 5 is a schematic representation of a computer system suitable for performing the techniques described with reference to FIGS. 2 to 4 .
DETAILED DESCRIPTION
Definition of Terms
It is useful to introduce a few terms:
Class: any type (e.g., classes and interfaces in Java™) in an object oriented programing language is a “class”.
Test Case: Test cases are used to verify the correctness of the software. These can be of various types, e.g., “unit test”, “functional test”, “system test”. These are collectively called “test cases”.
Dependency: Consider the example given in FIG. 1 . Class A has a direct dependency on class B, as A refers to B. Class C modifies persistent data represented by class D, which is consumed by class E in turn modified persistent data represented by class F. This data (class F) is consumed by class G. Therefore, both class E and class G have indirect dependency on class C. Any change in class C can potentially affect classes E and G.
Overview
An embodiment of the invention will be given using the example of Java™ programing language, being one type of object oriented programing languages.
The method broadly includes of the initial steps, as shown in FIG. 2 .
The reference structure of the software is found (step 10 ). Next, the important classes of the software are identified (step 12 ). These important classes include the classes used for representing the persistent data (e.g., the entity bean in a J2EE environment). Next, the references to the important classes are found (step 14 ) and the methods that are invoked for each of the important classes are found (step 16 ).
The dependency structure of the software is now determined (step 18 ), leading to identifying the directly dependent classes (step 20 ) and the indirectly dependent classes (step 22 ). The indirect dependencies are identified by looking for a producer/consumer relation for persistent data. The producer of data is a class that makes a non-read-only call (possibly in addition to some read-only calls) to the classes representing the persistent data, while the consumer of data is a class that makes a read-only call to the classes representing the persistent data.
The test case or cases for each class are now defined (step 24 ). This involves specifying a set of steps to be performed and the expected results at each step. The authors of such test cases are skilled programmers, and the nature of the test cases depends upon the software high level specficiations. In execution, if all the steps give the expected results, then the test case is considered to be successful. The test cases are associated with the “important” and dependent classes (step 26 ).
Now, with reference to FIG. 3 , when the code for a particular class is changed (step 30 ), the test case or cases associated with it are run (step 32 ). The dependent (i.e. both direct and indirect) classes for this type are also found (step 34 ), and the associated test cases are run (step 36 ). If a class is not important, then there will not be any associated test case to be run.
If any of the test cases fail (step 38 ) then appropriate action is taken (step 40 ), else the process ends (step 42 ). Such action can include informing the programmer, who can decide whether to retain the changes made in the code, or not.
If the developer wants to retain the changes, then the farther action to take is to notify the owners of the classes for which test cases failed, including the details of change in the code triggered this failure.
Detailed Implementation
Identifying the Important Classes
Typically, a large software program would define a template of the important classes by providing a set of classes and/or interfaces that the important business classes must extend/implement. These templates serve as the start points. For example, some of the important business classes/interfaces in the IBM WebSphere Commerce™ suite are the controller command interfaces, controller command implementation classes, task command interfaces, task command implementation classes, etc. Each controller command interface must extend a particular interface called com.ibm.commerce.command.ControllerCommand, either directly or by extending another interface, which is a controller command interface in turn.
To identify the important classes, the source (or the object) code is scanned to find the class names and their super classes (the classes this class is extending and/or implementing). A graph of the inheritance structure is then built using this information. This graph, in one form, is a directed acyclic graph 50 as shown in FIG. 4 . Node B 52 is a direct descendent of node A 54 in this graph if node B is a super class of node A. Node D 56 is an indirect descendent of node A if node C 60 is a direct or indirect descendent of node B, where node B, in turn, is a direct or indirect descendent of node D. Node G 62 is not a descendent or super class of any other node. All the direct or indirect descendents of the start points are important classes. Beginning at each start point, the important types are found from the graph using a depth first search or a breadth first search. For a start point of node B 52 , the important classes are class B itself, and classes D and E.
Finding References to a Given Class
There are a number standard utilities available to find the references to a given class. Additionally, utilities are also able to indicate which members of the given class are being accessed. By using any such utility, each method in the given class is represented by the set (possibly ordered) of member accesses of the important classes as identified above. The entire cell graph is generated, then filtered to remove all the classes that are not within the set of important classes.
A suitable utility is described in a document A Guide to the Information Added by Document Enhancer for Java, published by IBM Haifa Research Labs, Haifa, Israel, incorporated herein by reference. The utility can be downloaded from: http://www.haifa.il.ibm.com/proj Esc/systems/ple/DEJava/index.html.
Using the Reference to Important Classes Information to Find the Dependencies
The direct dependencies are easily found. If there is a reference to a given class, it is a direct dependency.
To detect an indirect dependency, the classes that represent the persistent data are found. The user has to provide the template for the classes representing the persistent data in the set of start points, and indicate that these templates represent persistent data. All the classes that have these start points as their direct or indirect descendents are found, and marked as classes representing persistent data. For example, in a typical J2EE environment, the persistent data is represented by the Entity Beans. So, the set of all Entity Beans represent the persistent data with which the software interacts. The classes that modify the persistent data are then found by looking for non-read-only calls to the Entity Beans. In this way the producer of the data is identifier. The consumer of data is one that makes read-only calls to Entity Beans. Given this producer/consumer relation for the data, the indirect dependencies are found.
Computer Hardware and Software
FIG. 5 is a schematic representation of a computer system 100 that can be used to implement the diagnostic techniques described herein. The computer system 100 can be thought of as a programmer's work station. Computer software executes under a suitable operating system installed on the computer system 100 to assist in performing the described techniques. This computer software is programed using any suitable computer programing language, and may be thought of as comprising various software code means for achieving particular steps.
The components of the computer system 100 include a computer 120 , a keyboard 110 and mouse 115 , and a video display 190 . The computer 120 includes a processor 140 , a memory 150 , input/output (I/O) interfaces 160 , 165 , a video interface 145 , and a storage device 155 .
The processor 140 is a central processing unit (CPU) that executes the operating system and the computer software executing under the operating system. The memory 150 includes random access memory (RAM) and read-only memory (ROM), and is used under direction of the processor 140 .
The video interface 145 is connected to video display 190 and provides video signals for display on the video display 190 . User input to operate the computer 120 is provided from the keyboard 110 and mouse 115 . The storage device 155 can include a disk drive or any other suitable storage medium.
Each of the components of the computer 120 is connected to an internal bus 130 that includes data, address, and control buses, to allow components of the computer 120 to communicate with each other via the bus 130 .
The computer system 100 can be connected to one or more other similar computers via a input/output (I/O) interface 165 using a communication channel 185 to a network, represented as the Internet 180 . In this way, a distributed team can co-operate in terms of portions of code being written or hosted from the other locations.
The computer software may be recorded on a portable storage medium, in which case, the computer software program is accessed by the computer system 100 from the storage device 155 . Alternatively, the computer software can be accessed directly from the Internet 180 by the computer 120 . In either case, a user can interact with the computer system 100 using the keyboard 110 and mouse 115 to operate the programmed computer software executing on the computer 120 .
Other configurations or types of computer systems can be equally well used to implement the described techniques. The computer system 100 described above is described only as an example of a particular type of system suitable for implementing the described techniques.
CONCLUSION
As a tool, the methodology greatly reduces the debugging effort required to manage the code in a distributed development environment.
Various alterations and modifications can be made to the techniques and arrangements described herein, as would be apparent to one skilled in the relevant art. | A system and method determine the possibility of adverse effect arising from a code change in a computer program. The system and method comprise the steps of identifying important classes within a computer program and determining directly and indirectly dependent classes of the important classes. The important classes comprise superclasses of the directly and indirectly dependent classes. The method associates test cases with the important classes and with the directly and indirectly dependent classes. Additionally, for a given code change to first important class, the method runs all test cases associated with the first important class and associated with dependent classes of the first important class, and indicates the possibility of an adverse effect if any run test case fails. | 6 |
This application is a National Stage of International Application PCT/EP2008/009197, filed Oct. 31, 2008, published May 22, 2009, under PCT Article 21(2) in English; which claims the priority of U.S. Patent Application No. 60/984,977, filed Nov. 2, 2007.
FIELD OF THE INVENTION
The invention relates to compounds and methods useful in detection and therapy of HPV-associated diseases. The invention is based on the elucidation of a mechanism by which replication of HPVs occurs in naturally infected tissues and cells. Moreover it is based on the identification of distinct epigenetic changes of the viral genome in infected cells that allows promotion of the affected cells to precancerous and cancerous cells. The invention therefore provides methods of diagnosing neoplasias and their precursor lesions as well as methods of preventing the development of malignancies or inhibiting tumor growth.
BACKGROUND OF THE INVENTION
The phenotype of single normal cells is in the human body is defined by the set of genes that are expressed at a certain time point. These gene expression patterns define the combination and individual levels of proteins that provide structure and function to all living cells and at a level of higher complexity all organs. Differentiation processes that are essential for all organs to function appropriately are also regulated by shifts in the level and combination of individual genes. Differential gene expression patterns determine the status of a cell for example as a stem cell that give rise to progenies that can undergo differentiation to fully differentiated cells, with substantially changed gene expression patterns. These finally conclude their lifespan by again changing their gene expression pattern and thereby adopting properties of aging and finally dying cells. Although the molecular control of these processes are far from being solved several lines of evidence suggest that substantial parts of this control is mediated by distinct methylation of certain GpC-islands within the human genome.
Conceptually the addition of methyl-(C(H) 3 )-groups to the certain nucleotides within the cell's genome results in a condensed and tightened structure of the methylated stretch of the genome and consequently inhibition of its transcription. Thus, heavily methylated parts of the genome are usually not transcribed into mRNA (silenced). This mechanism is an important part of gene regulation and imprinting and one of the central biological features that determine the critical steps in a living cell (Collas et al., 2007). The detail impact of methylation in differentiation processes has only very superficially been investigated so far (Kiefer, 2007). However, more detailed insight has been gathered during the transformation processes that are involved in the transformation of a normal cell into a full blown neoplastic cancer cell (Esteller, 2007; Feinberg, 2004). Particularly for genes with important tumor suppressive activities methylation of the promoter regions have been observed that resulted in reduced expression of the respective genes in the emerging cancer cells. Hence methylation is one of the central molecular steps in the inactivation of tumor suppressor gene besides deletion and/or mutation and has been clearly been proven for many tumor suppressive genes as for example the cyclin dependent kinase inhibitor p16 INK4a , the DNA mismatch repair genes MSH2, MHL1, and others (Esteller, 2007; Feinberg, 2004).
Besides its impact on the chromatin structure, more refined methylation of distinct nucleotides may also affect the binding properties of certain transcription factors (Klose and Bird, 2006). It thus may influence the affinity of positive or negative acting transcription factors and thus modifies the action and activity of the transcription factors which again results in either more active or reduced expression of the respective genes.
Human papillomaviruses are important epitheliotropic viruses that cause epithelial proliferations of the skin or mucosal surfaces. They attracted particular scientific interest when it became clear, that certain distinct types (high risk papillomaviruses, HR-HPVs) are associated with neoplastic lesions particularly of mucosal surfaces of the genital tract and most importantly of the uterine cervix (zur Hausen, 2002). It is generally accepted today that persistent infections of HR-HPV types (particularly HPV 16 and 18) are an essential prerequisite for the development of cervical cancer. Certain viral genes referred to as E6 and E7 were shown to be continuously expressed in cervical and other HPV-associated cancer cells. They further were shown to induce neoplastic transformation in in vitro cultured primary human epithelial cells and importantly, their expression is essentially required to induce and maintain the neoplastic growth features of cervical carcinoma cells or their high grade precursors.
Up to now, about 13 high risk HPV types have been characterized (Munoz et al., 2003). These viruses are commonly found also in women who have (not yet) developed any clinically detectable lesions. The peak incidence of the virus infections is found in young women at the ages of 15 to 30 years of life, whereas it declines in women of older age (Schiffman et al., 2007). This clearly points to the sexually transmitted characteristics of HR-HPV-infections that are also found in young men at comparable frequencies. The major difference between both genders however is that in males HR-HPV infections usually induce subclinical infections that are rarely realized by the host and that do not progress into invasive cancers, whereas in women long persisting infections apparently occur at substantially higher frequencies that can result in neoplastic transformation of the epithelial cells at the uterine transformation zone that finally may progress into invasive cancers. Interestingly this phenomenon seems to be restricted largely to few epithelial cells that occur at the transformation zone of the uterine cervix, whereas epithelial sites that are infected at comparable rates are substantially less prone to neoplastic transformation in comparison to epithelial cells of the uterine transformation zone.
During their normal life cycle HPVs infect first basal and parabasal cells of the epithelium. Several lines of arguments suggest that they first initiate a state of latent infection (Longworth and Laimins, 2004). During this the viral genome is replicated at very low copy numbers in single infected cells once the host cell divides, however no replication of the viral genome or even lytic infection is initiated at this stage. Due to technical limitations there is no true proof for the existence of this type of latent infection yet. It is anticipated rather from epidemiological studies that show that upon immunosuppression viral replication activity can be reactivated even if there is no evidence for de novo infections. These latent infections apparently can switch into active replicating infections. Here little viral gene expression activity is maintained in basal and parabasal cells, however, once the infected epithelial cells start to differentiate and reach the intermediate cell layers of the epithelium increasing gene expression is observed that triggers replication of the viral genomes in these differentiated cell layers. Interestingly, replication of viral genomes and expression of the viral early genes appears to be largely restricted to terminally differentiated cells that have irreversibly lost the capacity to proliferate and activated gene expression signatures of terminally differentiated epithelial cells that drive them into the pre-programmed pathway of differentiation and finally decay as squamous cell debris at the outer surface of the epithelium (Longworth and Laimins, 2004). Upon replication of the viral genomes in intermediate cells and once the epithelial cells reach during the normal differentiation processes the superficial cell layers, the viral genome again becomes re-programmed and expression of all early genes is stopped, whereas now full blown expression of the late genes L1 and L2 is observed that results in translation of the respective capsids proteins. These aggregate spontaneously to viral capsids in that the replicated viral genomes are included and finally the newly synthesized mature viral capsids are released from the decaying squamous cell debris at the outer surface of the epithelium and can re-initiate further infection cycles ( FIG. 1 ). These findings suggest that the viral replication cycle is strictly linked to the differentiation processes of the normal epithelium. However, since the molecular events that trigger the differentiation of the epithelial cells, little or nothing is so far known about the molecular features that are involved in the regulation of the viral gene expression patterns that control this complex replication process.
Critical structures for the regulation of the viral gene expression as well as for the replication of the viral genomes are retained in a sequence element referred to as long control region (LCR) or upstream regulatory region or (URR). In this element various binding sites for important positive and negative transcription factors as well as the origin of replication are found ( FIG. 2 ).
The papillomavirus E2 protein that is part of the several early expressed papillomavirus genes has substantial inhibitory functions on the expression of viral genes by binding to the viral promoter itself (Wells et al., 2000). It thus acts as a transcriptional repressor and prevents transcription of genes under control of the HPV URR element. This notion is based on a variety of molecular studies that have been performed in tissue culture models using non-differentiated epithelial cells grown in vitro or even cancer cell lines that retain the quasi non-differentiated phenotype of basal or parabasal cells. Expression of the E2 protein has been shown to result in down-regulation of the viral promoter and cessation of the expression of adjacent genes (Bouvard et al., 1994).
In cervical cancer cells, the papillomavirus genome is usually found to be integrated into host cell chromosomes (Pett and Coleman, 2007b). Whereas the integration site of the viral genome into the host cells genome appears to be randomly selected, is the viral genome of integrated viral DNA fragments usually preserved in a very peculiar manner. First of all are fragments that encompass the URR, and the E6 and E7 genes in all yet analyzed retain in an configuration that would still permit expression the E6 and E7 genes even from integrated viral genome copies, whereas the downstream located genes E2 and the late gene cassette is usually disconnected from the regulatory elements within the URR and hence functionally or even structurally inactivated (zur Hausen, 2002). Interestingly, in all HPV-associated carcinoma cells that have been investigated with this regard, expression of the viral E6 and E7 could be confirmed. As mentioned earlier, these genes confer important growth regulatory features to replicating cells through complex interactions with a number of host cell proteins that at least in part are involved in the regulation of the cell cycle, differentiation processes, and death cascades. The expression of these genes is a critical and sufficient prerequisite to induce and maintain neoplastic transformation of epithelial cells. If the expression of these genes is blocked in transformed cells these cells fall into cell cycle arrest, cease growth and eventually die (von Knebel et al., 1988).
In line with this observation is the open reading frame that encodes the E2 gene of HR-HPV types usually disrupted in HPV associated cancers. Re-introduction of functionally active E2 proteins into HPV-transformed cells therefore results in reversion of the neoplastic phenotype, cell cycle arrest and eventually cell death (Wells et al., 2000).
It is thus generally accepted among scientists in the field that disruption of the E2 ORF by integration into the host cell chromosomes is a critical if not absolutely essential step in the molecular cascade that finally results in malignant transformation of HPV-infected epithelial cells (Pett and Coleman, 2007a; Pett et al., 2006; Pett et al., 2004; Alazawi et al., 2002).
The tight association of the HPV replication cycle with features of epithelial differentiation suggests that the host cell milieu plays a critical role in the control of viral gene expression and replication (see FIG. 1 ). Several lines of evidence suggest that methylation and other forms of epigenetic regulation are involved in the gene expression and replication regulation of the viral genome. Most of these data are based on artificial tissue culture models. All models so far did not allow explaining the details of the differentiation dependent regulation of viral gene expression and replication.
Methylation of papillomavirus DNA was already described about 20 years ago (Burnett and Sleeman, 1984; Wettstein and Stevens, 1983) Its biological significance, however, in the regulation in papillomavirus gene expression control and the associated carcinogenic effects are still only poorly understood (List et al., 1994; Rost et al., 1993; Thain et al., 1996). It appears that CpG methylation in HPV-16 and HPV-18 genomes occurs more often in LCR regions and part of L1 ORF region than in any other parts of the virus genome in cervical cancer cell lines (Badal et al., 2004; Badal et al., 2003). Moreover, methylation particularly of the L1 gene appears to be associated with integration of the foreign viral DNA into the host cell genome during carcinogenesis and was thus suggested as potential biomarker for neoplastic conversion of HPV-infected cells (Kalantari et al., 2004; Turan et al., 2006). Further data also suggest that CpG methylation in E2BS prevents E2 protein binding in vitro (Thain et al., 1996) and modulates E2 protein function in cells in transcription activation (Bhattacharjee and Sengupta, 2006; Kim et al., 2003). However, DNA methylation in cancers is not restricted to HPV DNA. As outlined earlier, it is regarded as a very important feature, but rather occurs as a frequent event throughout the host genome (Esteller, 2007). The frequency of hypermethylation of many cellular genes has been found being increased significantly with increasing severity of neoplasia (Banno et al., 2007; Dong et al., 2001; Feng et al., 2005; Jeong et al., 2006; Kang et al., 2006; Lai et al., 2007; Lea et al., 2004; Reesink-Peters et al., 2004; Seng et al., 2007; Steenbergen et al., 2004; Virmani et al., 2001; Widschwendter et al., 2004).
A recent study investigated the presence or absence of methlytion of CpGs in E2 binding sites E2BS2 to 4 of HPV 16 in normal epithelium and cervical carcinoma cells (Bhattacharjee and Sengupta, 2006). These authors report that methylation was found in defined CpG islands that are located in the E2BS 2 to 4 proximal to the P97 promoter in the transformed tissues.
However, a clear consistent pattern that would explain distinct biological features with defined changes of the methylation pattern at specific sites could not been delineated in this study.
Kim et at (Kim et al., 2003) reported that hypomethylation was associated with in highly differentiated cell populations of an in vitro tissue culture model using W12 cells. In contrast, the HPV16 LCR from poorly differentiated, basal cell-like cells contained multiple methylated cytosines and were often methylated at E2BSs.
Moreover it has been disclosed in the prior art that human cancers frequently show altered patterns of DNA methylation, particularly at CpG islands. Methylation within islands has been shown to be associated with transcriptional repression of the linked gene. Genes involved in all facets of tumor development and progression can become methylated and epigenetically silenced. Re-expression of such silenced genes can lead to suppression of tumor growth or sensitization to anticancer therapies. Epigenetic agents that can reverse DNA methylation are now undergoing preclinical evaluation and clinical trials in cancer patients. The nucleoside inhibitors 5-azacytidine and decitabine have been tested in many phase I and II trials against many forms of cancer. However, the dose-limiting toxicity for both is myelosuppression, and the most commonly reported non-hematologic adverse effect was nausea and vomiting. Therefore a systemic therapy of cancers with demethylating agents is commonly causing severe side effects.
Specific DNA methylation inhibitors can be used for treating cosmetic and dermatologic conditions. It has been shown that 5 azacytidin inhibits both basal level TGFβ-induced collagen biosynthesis by normal human firoblasts. Collagen has a direct effect on scarring. Hence, inhibition of over-production of collagen in human skin results in inhibition of scar formation. Moreover, the combination of UV treatment and demethylation agent can be used for treatment of cancerous and pre-cancerous skin lesions.
The current invention relates to the finding that methylation of distinct, specific sequence elements within the papillomavirus genome are controlling the viral life cycle, replication and gene expression pattern. Moreover, it relates to the finding that a specific change of this methylation pattern is responsible for the inititiation of the neoplastic transformation induced by some papillomaviruses. This is particularly important for lesions of the mucosal epithelia of body cavities such as e.g. of the uterine cervix, vagina, vulva, anus and of the oropharyngeal tract. To overcome the unwanted and in part unbearable side effects associated with systemic therapies with demethylating agents the inventors found that especially for treatment of HPV related lesions and cancers of the mucosal epithelia of body cavities a topical treatment with demethylating agents may serve as a very effective approach to cure cancers without causing unwanted side effects to the patients.
SUMMARY OF THE INVENTION
The current invention relates to the topical application of demethylationg agents for treatment and/or therapy of lesions of e.g. mucosal epithelia of body cavities. In this respect the present invention further pertains to methods for treatment and therapy of HPV associated lesions. HPV associated lesions comprise e.g. cervical cancer and it's precursor stages as well as warts of the skin.
Further the current invention relates to a pharmaceutical composition comprising a demethylating agent for topical application on mucosal epithelia of body cavities for treatment of HPV related lesions and cancer by preventing viral replication and molecular transition into transforming infections. In this respect the present invention further pertains to a pharmaceutical composition for treatment and prevention of HPV associated neoplasias. The pharmaceutical composition comprises a pharmaceutically acceptable carrier and an epigenetic inhibitor or a demethyaltion agent that interferes with the specific methylation pattern at E2BS1, NFIBS, TEF-1BS and/or SP1 BS.
The present invention also pertains to a method for discriminating latently infected cells from cells with productive HPV infection by determining the methylation pattern of the HPV E2BS1, NFIBS, and/or TEF-1BS (see FIG. 5 ).
An isolated nucleic acid comprising the sequence of Seq ID 1 to 8, wherein the nucleic acids are methylated at positions given in capital letters in the sequences below.
Seq ID 1:
E2BS 1 acCGaattCGgt
from nt 7450 to 7461
CpG 7452, 7458 nt
Seq ID 2:
E2BS 2 acCGatttgggt
from nt 7857 to 7869
CpG 7859 nt
Seq ID 3:
E2BS 3 acCGaaatCGgt
from nt 35 to 46
CpG 37, 43nt
Seq ID 4:
E2BS 4 acCGaaacCGgt
from nt 50 to . . . 61
CpG 52, 58nt
Seq ID 5:
NFI cttgccatgCGtgccaaatc
from nt 7541to 7560
CpG 7550nt
Seq ID 6:
NFI aatcactatgCGccaaC
from nt 7663 to 7679
CpG 7673, 7679nt
Seq ID 7:
TEF-1 tacatacCGct
from nt 7684 to 7694
CpG 7691nt
Seq ID 8:
Sp1 taagggCG
from nt 25 to 32
CpG 31nt
For the above Sequences all nucleotide positions are cited according to full-genome HPV 16 sequence NCBI Acc. N NC — 001526. The C given in capital letters correspond to methyl Cytosine. The G given in capital letters indicate sites where on the reverse complementary strand a methyl-cytosoine is located.
An isolated nucleic acid of Seq ID 9 to 15 below
Seq ID 9:
E2BS 1 atTGaattTGgt
Seq ID 10:
E2BS 2 atTGatttgggt
Seq ID 11:
E2BS 3 atTGaaatTGgt
Seq ID 12:
E2BS 4 atTGaaatTGgt
Seq ID 13:
NFI tttgttatgTGtgttaaatt
Seq ID 14:
NFI aattattatgTGttaaT
Seq ID 15:
TEF-1 tatatatTGtt
Seq ID 16:
Sp1 taagggTG
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 : Schematic representation of the viral life cycle and progression to transforming infections.
FIG. 2 : Schematic representation of the HPV 16 genome and enlargement of the structure of the long control (LCR) or upstream regulatory region (URR). The relative location of the binding sites for the viral E2 protein and the SP1 transcription factor are indicated.
FIG. 3 : Schematic representation of the analysis of the methylation pattern as described by (Bhattacharjee and Sengupta, 2006) who compared the methylation pattern of E2BS 4 between normal and neoplastic epithelium and our results that revealed major differences between non-transformed and transformed (p16INK4a-positive) epithelium in E2BS1.
FIG. 4 : Example of microdissected cervical epithelium; upper panel: epithelium upon early HPV-infection (emerging evidence of CIN 1), however not transformation and hence not staining for p16INK4a; lower panel: high grade squamous intraepithelial lesion with deregulated HPV E6/E7 oncogene expression and evidence for high grade squamous intraepithelial lesion (HSIL).
FIG. 5 : Schematic representation of the methylation pattern of critical transcription factor binding sites within the HPV 16 URR.
FIG. 6 : Principle of the COBRA-Assay and the results of the analysis of some clinical samples of the E2BS1 of the HPV 16 genome.
FIG. 7 : Structure of Normal Squamous Epithelium [KossLG, et al, 1999]
FIG. 8 : Effect of E2BS-1 methylation on the p97 early promoter activity.
FIG. 9 : Effect of 5-azacytidin on the p97 early HPV16 promoter activity
DETAILED DESCRIPTION OF THE INVENTION
The inventors have investigated the methylation pattern of human papillomavirus genomes, in particular the methylation pattern of the URR including its cognate E2BS during three postulated phases of the viral life cycle, i.e. a. latent infection, b. replicating infection, and c. transforming infection. To determine the detailed methylation status of HR-HPV genomes within epithelial cells of different differentiation stages, tissues were micro dissected (see FIG. 4 ) and HPV sequences were amplified from the different cell layers to allow a precise assessment of distinct methylation patterns of the HPV genome using bisulfite sequencing PCR (BSP) (see FIG. 5 ).
HPV associated lesion as used here refers to lesions induced by HPV infections encompassing all alterations of any epithelium induced by either acute or persistent HPV-infections. These may range from small warts without clinical impact, rather exophytic growing papillomas, condylomata including inverted papillomas, on the skin, the genital tract, the mucosal surfaces etc. as well as pre-neoplastic and invasive lesions induced by oncogenic papillomavirus genotypes including metastasis derived thereof. Many of the HPV-induced pre-neoplastic or neoplastic lesions occur at the transition zone of different epithelial tissues, particularly where a single layer glandular epithelium meets a multilayered squamous epithelium as for example at the cervical transformation zone, the junction of the rectal mucosa with the anal epithelium, or within the oropharynx in the area of the tonsils.
The inventors to the present invention have found that in normal epithelium that has not yet been affected by cytopathic effects of the HPV, viral genomes may persist in basal cells, clearly demonstrating that there is a latent stage of virus infection in basal and parabasal cells (data not shown). Viral genomes in this latent stage are completely methylated in all CpGs that could be analyzed, suggesting that overall methylation of the viral genomes mediates the latency of the infection and prevents viral gene expression thereby also preventing cyto-pathological or histopathological alterations of the infected epithelium. Thus the inventors found that there is a link between the methylation status of HPV genomes and the latent mode of infection. It is important to note that at this stage methylation was also found in the E2BS1.
If viral genomes were isolated from micro-dissected cells of early dysplastic lesions (CIN1) distinct changes of the methylation pattern were observed depending on the differentiation status of the host cell and the respective CpG within the viral genome (see FIG. 5 ). In the basal cell layers, unmethylated E2BSs (1-4) in distinct parts of the URR were observed. Interestingly the E2BS1 was not methylated allowing presumably for binding and repression of the viral enhancer element. If viral DNA was isolated from the intermediate cell layers parts of the genome become de-methylated. This allows access of positive transcription factors (TF) like NFI, TEF-1, and others to stimulate the expression of viral genes. Enhanced viral gene expression results in line with increasing de-methylation in differentiated cells and thus initiation of viral genome replication ( FIG. 5 ).
In the superficial cell layers, all CpG within the early promoter including E2 (E2BSs 2,3 and 4) and SP1 binding sites were methylated, suggesting inactivation of the early promoter activity.
In lesions that progressed already to high grade squamous intraepithelial lesions (HSIL) that therefore show abundant expression of the viral oncogenes E6 and E7 highlighted by the overexpression of the p16 INK4a marker (Klaes et al., 2001)(see FIG. 4 ), consistent methylation of the E2BS1 was observed ( FIG. 5 ). This suggests that by preventing access of the E2 protein to this particular binding site, methylation abolishes the negative transcription regulation and allows for uncontrolled high level of viral gene expression mediated by the HPV 16 URR (LCR).
This methylation pattern was compared between p16 INK4a positive parts of the lesions that display deregulated E6 and E7 oncogene expression and the HPV infected but p16 INK4a negative part of the lesion that apparently still retain restricted HPV E6 and E7 gene expression lesions using the Combined Bisulfite Restriction Analysis (COBRA) (Xiong and Laird, 1997). The data presented in FIG. 6 support the notion that methylation of the E2BS1 goes along with deregulated expression of the viral oncogenes.
The E2 binding Sites are defined as follows:
E2BS 1 acCGaattCGgt from nt 7450 to 7461 CpG 7452, 7458 nt E2BS 2 acCGatttgggt from nt 7857 to 7869 CpG 7859 nt E2BS 3 acCGaaatCGgt from nt 35 to 46 CpG 37, 43nt E2BS 4 acCGaaacCGgt from nt 50 to . . . 61 CpG 52, 58nt
BS positions according to full-genome HPV 16 sequence NCBI Acc. N NC — 001526.
The normal epithelium may be described as depicted in FIG. 7 . The outermost layer of the skin and mucosa consists of multiple epithelial cell layers distinguished by a progressive change in morphology that can be divided into three principal zones (FIG. 20) [Koss L G, et al; Introduction to Gynecologic Cytopathology with Histologic and Clinical Correlations, 1999:23-30.]:
The basal zone consists of one or two layers of low differentiated basal cells (stratum basale) that are spherical and have relatively large nuclei. In normal squamous epithelium, the basal stem cells are the only cells capable of dividing. The basal cells are attached to the basement membrane which separates the epidermis from the dermis.
The intermediate zone of the epithelium represents the bulk of the epithelial thickness and consists of several layers of cells (the para-basal layer or stratum spinosum and the intermediate squamous layer or stratum granulosum) that increase in size toward the surface. Once no longer attached to the basement membrane, these cells exit the cell cycle, stop dividing, and begin to differentiate.
The superficial zone includes rows of larger, flattened cells (mature squamous layer or stratum corneum) with small condensed nuclei and cytoplasm filled with glycogen. The outer layer of the superficial zone consists of terminally differentiated cell.
The analysed region between genomic positions 7198 and 161 contains 16 CpGs ( FIG. 5 ). The analysed region can be divided into 3 functionally distinct segments, which have called the 5′LCR, enhancer and promoter. The 5′LCR contains 4 CpG including CpGs (nt7452, nt7458) within E2BS1 (7450-nnnnn-7461). The enhancer contain five CpGs including 4 CpGs (nt7550, 7673, 7679 and 7691) within NFIBS (7541-cttgccatgCGtgccaaatc-7560; 7663-aatcactatgCGccaaC-6379) and TEF-1 BS (7684-tacatacCGct-7694). The last seven CpGs in the promoter, six of them (nt7859, 31, 37, 43, 52, 58) overlap with an Sp1(25-taagggCG-32) and three E2 binding sites (E2BS 2 7857-acCGatttgggt-7869; E2BS 3 35-acCGaaatCGgt-46 and E2BS 4 50-acCGaaacCGgt-61).
In contrast to what has been published in the previous reports, we found that in normal epithelium that has not yet been affected by cytopathic effects of the HPV, viral genomes may persist in basal cells, clearly demonstrating that there is a latent stage of virus infection in basal and parabasal cells (data not shown). Viral genomes in this latent stage is completely methylated in all 16 CpGs that could be analyzed ( FIG. 5 ), suggesting that overall methylation of the viral genomes mediates the latency of the infection and prevents viral gene expression thereby also preventing cyto-pathological or histopathological alterations of the infected epithelium. This observation is new, since up to now, no data have been reported that link the methylation status of HPV genomes with the latent mode of infection. It is important to note that at this stage methylation was also found in the E2BS1.
If viral genomes were isolated from micro-dissected cells of early dysplastic lesions (CIN1) distinct changes of the methylation pattern were observed depending on the differentiation status of the host cell and the respective CpG within the viral genome (see FIG. 5 ).
In the promoter region, DNAs isolated from the basal cells as well as cell fractions from intermediate layer, of the 12 amplimer clones analysed, all contained unmethylated CpGs. A strikingly different result was observed with HPV16 DNAs isolated from the more differentiated cells of the superficial cell layers. In 8 of the 12 amplimers clones generated from HPV16 DNA isolated from the superficial layer enriched for differentiated cells, CpGs within the promoter including E2BSs (2,3 and 4) and SP1 site, were methylated.
In the enhancer region the 4 CpGs within two NFIBSs and one TEF-1BS were heavily methylated in the basal cells but show a lower degree of methylation in the more differentiated cells. This allows access of positive transcription factors (TF) like NFI, TEF-1, and others to stimulate the expression of viral genes. Enhanced viral gene expression results in line with increasing de-methylation in differentiated cells.( FIG. 5 ).
In the 5′LCR segment all 4 CpGs were unmethylated irrespective of differentiation stage. Interestingly the E2BS1 was not methylated allowing presumably for binding and repression of the viral enhancer element.
In lesions that progressed already to high grade squamous intraepithelial lesions (HSIL) that therefore show abundant expression of the viral oncogenes E6 and E7 highlighted by the overexpression of the p16 INK4a marker (Klaes et al., 2001) (see FIG. 4 ), specific methylation pattern was observed ( FIG. 5 ). In the promoter and enhancer regions 4 CpGs within NFIBS and TEF-1 BS were methylated. In the 5′LCR 3 CpGs were methylated including 2 CpGs within E2BS1. This suggests that by preventing access of the E2 protein to this particular binding site, methylation abolishes the negative transcription regulation and allows for uncontrolled high level of viral gene expression mediated by the HPV 16 URR (LCR).
This allowed us to delineate distinct methylation patterns of the viral genomes with biological properties of the respective viral genomes within these host cell tissues. The key findings of this research are:
In latently infected cells that do not display viral activity, the HPV genome is heavily methylated in almost all, if not all CpG islands, thereby preventing any biologically relevant expression of viral genes. For example, more than 80%, preferably 90%, preferably 95%, more preferably 98% of the CpG islands are methylated in cells of basal zone, intermediate zone and superficial zone. This mediates complete hiding of latent HPV-infections in few epithelial stem cells and that can then persist for undetermined periods of time. (see FIG. 5 )
Under yet not characterized conditions, the latent state of HPV-infections in individual cells can switch into a replicating infection mode. In the basal cells, the early HPV promoter (including CpGs within E2BS2,3 and 4 and SP1 binding sites as well as 5′ long control region (including E2BS1) contained unmethylated CpGs. Thus, in the enhancer region 4 CpGs within NFI and TEF-1 sites were heavily methylated. This pattern of methylation suggests low activity of the p97 promoter. ( FIG. 5 )
In intermediate cells, the HPV enhancer shows a lower degree of methylation in the more differentiated cells as compared to basal cells, leading to increased activity of the p97 promoter due to binding of the transcription activators such as nuclear factor I (NFI) and transcriptional enhancer factor TEF-1. However, activity of the early promoter is retained on a certain level owing to E2 negative control. (E2BS1 demethylated).
In the terminally differentiated superficial cells, all CpG within the early promoter in including E2 (E2BSs 2,3 and 4) and SP1 binding sites were methylated, suggesting inactivation of the early promoter activity.
The fact that the methylation state of the viral genome is substantially changed depending on the degree of epithelial differentiation of the host cells suggesting that DNA methylation have important roles in the viral life cycle and presumably also epithelial differentiation. Moreover, functionally distinct, both high- and low-risk virus types may share common mechanisms for regulating their productive life cycles.
Upon long persistence of replicating infections, infected cells of the basal and parabasal cells may switch the methylation profile of the basal and parabasal cells into the transforming mode of HPV-infections that are primarily characterized by methylation of the EBS1, nt 7459. Methylation of this CpG-islands results in loss of E2 binding to E2BS1 and interestingly, loss of its inhibitory function on the URR. Consequently, respective HPV genomes loose thereby the intracellular surveillance control and start to express substantial levels of the viral oncogenes E6 and E7 in the basal cell compartment.
Mapping of methylated CpGs in the URR of HPV16 by bisulfate genomic sequencing (BGS) technique.
DNA isolated from laser-microdissected cells with different degree of differentiation (basal, intermediate and superficial layers) was analysed for the methylation status of the URR of HPV16 using bisulfite genomic sequencing (BGS).
Bisulfite modification of DNA was carried using the EZ DNA methylation kit (Zymo Research, Orange, Calif.) according to the manufacturer's recommendations. DNA from the Caski and SiHa cell lines was used as control and treated concurrently with the samples to ensure complete bisulfite treatment.
A nested BSM-PCR system was developed and performed using the primers design to span the URR of HPV16 (from nt 7198 to nt 161; NC — 001526) (Table1).
Primer
Sequence 5′ to 3′
5′ LCR
5′ LCR16_for
TTTGTATGTGTTTGTATGTGT
5′ LCR16_rev1
TTAAACCATAATTACTAACATAA
5′ LCR16_rev2
ACATTTTATACCAAAAAACATA
Enhancer
Enh16_for
TAGTTTTATGTTAGTAATTATGGTT
Enh16_rev1
ATTAACCTTAAAAATTTAAACC
Enh16_rev2
AAAAATTTAAACCTTATACCAA
Promoter
Prom16_for1
TTGTATGTGTTTGTATGTGT
Prom16_for2
GGTTTAAATTTTTAAGGTTAAT
Prom16_rev
ACAACTCTATACATAACTATAATA
PCR reaction mixtures were performed in a total of 50 μl containing 10×PCR buffer, 5 μl 50 mM MgCl2, 0.5 μl 2 mM deoxynucleotide triphosphates, 0.5 mM of each PCR primer (1.5 μl primer (25 μmol/μl)), 2.0 U Platinum Taq (Invitrogen) and 2 μl of the bisulfite modified DNA. Negative controls without DNA were included in each analysis. Amplification conditions were as follows: initial denaturation at 94° C. for 2 min followed by 40 cycles and 30 cycles for the nested PCR of 94° C. for 30 s, annealing at 50° C. for 30 s, extension at 72° C. for 40 s and finally 72° C. for 4 min. PCR products were separated via electrophoresis and isolated from 2% agarose gels stained with ethidium bromide. Isolated PCR products were then purified by QIAquick Gel Extraction Kit (Qiagen, Hilden) according to the manufacturer's instructions. Purified PCR fragments were cloned the TA Cloning System (Invitrogen) and 12 individual clones were sequenced to identify the presence and patterns of methylated CpGs within HPV16 DNA
Sequencing of bisulfite modified sample DNA was performed using the BigDye terminator sequencing kit (Applied Biosystems, Foster City, Calif.) according to the manufacturer's recommendations. The sequencing PCR products were analyzed on the ABI Prism 310 Genetic Analyzer.
Determination of methylation status of HPV16 E2BS1: the Combined Bisulfite Restriction Analysis (COBRA)
In order to determine the methylation status of the E2BS-1 [7450-acCGaattCGgt-7461], distal to P97 promoter of HPV16 we used the Combined Bisulfite Restriction Analysis (COBRA.) (Xiong and Laird, 1997).
DNA isolated from p16-positive and p16-negative lesions was bisulfite treated using the EZ DNA methylation kit (Zymo Research, Orange, Calif.) according to the manufacturer's recommendations.
After treatment, 5 μl of aliquot were amplified in 50 μl of solution containing 1× buffer, 1.25 mM deoxynucleotide triphosphate mixtures, 2.5 μmol of each primer, and 1.5 unit of Taq DNA polymerase (Life Technologies, Inc.). PCR was carried out as follows. After a hot start, the cycling parameters were: 94° C. for 30 s, 50° C. for 30 s, and 72° C. for 60 s for 45 cycles and final elongation at 72° C. for 4 min. Primers used for COBRA were as follows: mHPV16_E2BS1 for 5′AATTGTGTTGTGGTTATTTATTG3′ and mHPV16_E2BS1rev 5-CAAATTTAAACCATAATTACTAAC3′.
After amplification, PCR products were digested with the restriction enzyme EcoRI (New England Biolabs). The EcoR I recognizes E2BS1 sequences unique to the methylated and bisulfite-converted DNA ( FIG. 6 ). DNA was electrophoresed in 2% agarose gels. The gels were stained with ethidium bromide.
We can explain tissue specificity. Since HPVs need specific methylation machinery to support their viral cycle.
These data suggest that the methylation state of the viral genome is substantially changed depending on the degree of epithelial differentiation of the host cells. Moreover, our results indicate that E2 binding site 1 methylation might play an important role in the initial stage of cervical cancer progression.
Therefore, the use of demethylating agents that could disturb normal viral cycle and will eventually be a more rational
Demethylating agent as used herein may be any agent affecting the methylation status of nucleic acids and may be e.g. 5-Azacytidine (Vidaza), 5-Aza-20-deoxycytidine (Decitabine, dacogen), Arabinosyl-5-azacytidine (Fazarabine) 5-6-Dihydro-5-azacytidine (DHAC) 5-Fluoro-20-deoxycytidine (Gemcitabine), Epigallocatechin-3-gallate (EGCG), Hydralazine, Procainamide, Procaine, Zebularine, or a combination thereof. Another classes of demethylating agents are specific oligonucleotides (for example EGX30P), specific RNAi or DNMT1 antisense (MG98). In a preferred embodiment, 5-azacytidine, 5-aza-2-deoxycytidine, or a combination thereof is utilized.
A Pharmaceutical composition for topical administration according to the present invention may be provided in formats like aerosols, cream, gel, liquid, ointment, paste, patch, tampons, caps and any other device and or formulations for controlled release of demethylating agents.
Pharmaceutical compositions according to the present invention may additionally comprise active ingredients. Active agents of the invention can be used to provide controlled release pharmaceutical formulations containing as active ingredient one or more compounds of the invention in which the release of the active ingredient can be controlled and regulated. Control release compositions may be achieved by selecting appropriate polymer carriers such as for example poly(dimethylsiloxane), ethylene vinyl acetate copolymers, polycarophil, hydroxypropyl methylcellulose and polyacrylic acids. The rate of drug release and duration of action may also be controlled by incorporating the active ingredient into particles, e.g. microcapsules, of a polymeric substance such as hydrogels, and the other above-described polymers. Controlled release may be achieved by methods that include colloid drug delivery systems like liposomes, microspheres, microemulsions, and others.
The demethylating agents may be e.g. 5-azacytidine or 5,6-Dihydro-5-azacytidine hydrochloride. Also a chemically stable, soluble analog of 5-azacytidine, can be used in a hydrophilic cream base or hydrophilic gel base. For example, 1% cream is a topical preparation containing 5-azacytidine 1% w/w or 5,6-Dihydro-5-azacytidine hydrochloride, 1% w/w in a hydrophilic cream base containing stearic acid, Aquaphor®, isopropyl palmitate, polyoxyl 40 stearate, propylene glycol, potassium sorbate, sorbic acid, triethanolamine lauryl sulfate, and purified water.
Additives may also include buffers (such as sodium phosphate), humectants (such as glycerin or sorbitol) and other excipients known to those skilled in the art. 1% aqueous gel contains 1% w/w 5-azacytidine or 1% w/w or 5,6-Dihydro-5-azacytidine hydrochloride in a base of betadex, edetate disodium, hydroxyethyl cellulose, methylparaben, niacinamide, phenoxyethanol, propylene glycol, propylparaben and purified water. 5-azacytidine (1%) hydrophilic gel can be prepared by incorporating 1% 5-azacytidine by weight into hydroxyethylcellulose, Natrosoll 1% solution in distilled water.
The principal may be applied to a combination of different active agents of the invention or to a combination of the different active agents of the invention with other drugs that exhibit anti-HPV activity.
While it is possible for the demethylating agents to be administered alone it is preferable to present them as pharmaceutical formulations. The pharmaceutical compositions of the present invention comprise a) a demethylating agent and b) a pharmaceutically acceptable carrier.
In another embodiment the pharmaceutical composition comprises a) a demethylating agent, b) an antiviral agent to provide a synergistic effect against a viral infection, and c) a pharmaceutically acceptable carrier.
5-azacytidine, 5-aza-2-deoxycytidine, or a combination thereof may be prepared into various pharmaceutical formulations which are presently known or may be developed in the future.
In certain embodiments 5′-Azacytidine is applied in topical pharmaceutical compositions at a concentration of 0.001%-50% w/w, more preferred of 0.005%-20% w/w, even more preferred of 0.005%-10% w/w. The demethylating agent is a cream comprising a demethylating agent at a concentration of from about 0.001% to 10%.
TABLE 2 Brush Tampons Cervical caps % w/w % w/w % w/w 5{grave over ( )}Azacytidine 0.1-5 0.1-1 0.1-1 5,6-Dihydro-5- 1-10 1-5 1-5 azacytidine Epigallocatechin 1-10 1-5 1-5 3-gallate (EGCG)
Application schedules for the different forms are: Brush—every 8 h, Tampons—daily. Cervical cap every 2 days.
Application of 5′-Azacytidine is used at a dosage of 0.1 μg to 100 μg, in another embodiment at a dosage for each single application of 0.5 μg to 50 μg, in yet another embodiment at a dosage of 1 μg to 10 μg in a further embodiment at a dosage of 500 μg to 2 μg. In certain embodiments of the invention 1 dosage per day, two dosages per day, three dosages per day, four dosages per day or even five or more dosages per day are applied. In certain embodiments of the invention the application is designed to be continuous using a medium continuously releasing the demethylating agent. In further embodiments the dosage is given weekly, twice a week, thrice a week, every other week or monthly. Such dosage may be applied for example for a total period of 1 week, of two weeks, of three weeks, four weeks, five weeks, six weeks, two months, three months or even longer. In certain embodiments the period of application may be half a year, one year or even longer.
One example of device that ca be used for drug delivery to the cervix is a cotton swab or brush
Other example of device that ca be used for drug delivery is the cervical cap. For example, cavity rim caps adhere to the cervix. The cavity rim caps are Prentif™ Caps. The Prentif™ Cervical Cap covers a patient's cervix and is used as a barrier method of contraception. Similarly, the TodayR™ contraceptive sponge was a sponge-like device shaped to fit over a patient's cervix.
Other types of devices used in connection with a patient's cervix is a vaginal tampon, vaginal ring, vaginal strip, vaginal capsule, bioadhesive film or sponge. Device is incorporated with the composition comprising from about 1 to about 10 mg mg of the epigenetic agent, about 10% of hydroxypropyl methylcellulose, about 70% of saturated triglyceride of fatty acids for a hydrophilic drug or PEG 6000/PEG 400 for a lipophilic drug and about 15% of ethoxydiglycol.
EXAMPLES
Example 1
Detection of Methylation Pattern
To investigate whether methylation of HPV 16 URR is influenced by differentiation status of the host epithelial cells, we analyze HPV16 DNA isolated from laser-microdissected normal epithelial cells with different degree of differentiation using bisulfite genomic sequencing (BGS).
The p97 HPV16 promoter in the basal cells derived from the normal epithelium as well as cell fractions from intermediate layer contained unmethylated CpGs. In contrast, HPV16 promoter in superficial layer enriched for differentiated cells was methylated, including CpGs within E2 (E2BSs 2,3 and 4) and SP1 binding sites. In the enhancer region we found decreased methylation of one CpG site (7454) in all differentiation stages. Thus, the other 4 CpGs (CpG) were heavily methylated in the basal cells but show a lower degree of methylation in the more differentiated cells. 5′ LCR region was hypomethylated in all differentiation stages.
We further compare the methylation pattern of HPV16 URR in HSIL lesions with corresponding normal epithelium using over-expression of the cyclin dependent kinase inhibitor p16INK4a as biomarker for HPV-transformed epithelial cells using combined bisulfite restriction analysis (COBRA).
These data indicate that the methylation of the E2BS1 specifically occurs during the transition of replicating to transforming HPV infections.
Example 2
Assessment of Diagnosis
101 samples (smears and punch biopsies), which are derived from cytologically and histologically confirmed low-grade (LSIL, n=53) and high-grade (HSIL, n=48) lesions infected with HPV16 are tested for the presence of the E2BS1 methylation by combined bisulfite restriction analysis (COBRA).
The detection of the specific LCR HPV16 methylation provides a molecular marker for detecting pre-cancerous lesions with high risk for cancer progression.
TABLE 3
E2BS1 methylation,
Sample N
(%)
LSIL
53
12 (22.6)
HSIL
48
36 (75)
Methylation of E2BS1 was present in 75% high-grade lesions but only in 22.6% of low grade intraepithelial lesions. Thus, the detection of the specific LCR HPV16 methylation may provide a molecular marker for detecting pre-cancerous lesions with high risk for cancer progression.
To verify whether E2 binding to E2BS1 is responsible for the activation of the p97 promoter we analyzed the effect of E2BS1 methylation on the activity of P97 in transient transfection experiments. Selective methylation of the 2 CpG dinucleotides in E2BS1 were introduced into the wild-type HPV16 LCR. We co-transfected normal human foreskin keratinocytes with increasing amounts of an expression vector for HPV16 E2 and about 50 ng of a reporter plasmid containing either the entire HPV16 LCR in front of the luciferase gene (E2BS1-LCR16-Luc) or an LCR with the methylation in E2BS1 (methE2BS1-LCR16-Luc). Methylation of E2BS1 leads to 4-6 fold activation of the early p97 HPV16 promoter ( FIG. 8 ). This data suggest that by modulating of the E2 protein binding to this particular binding site, methylation activates the p97 promoter and allows for uncontrolled high level of viral gene expression.
These data further show, that detection of the specific methylation of E2BS1 can be used to identify lesions that have already undergone the transition from acute to transforming HR-HPV infections. Methylation of the E2BS1 may thus serve as biomarker for HSIL.
Example 3
Therapeutic Application of 5′ Azacytidine in Cell Culture
The impact of treatment with epigenetic inhibitors (demethylation agents) on the activity of the p97 promoter is assessed using luciferase assay. Normal human keratinocytes transfected with the reporter plasmid LCR16_Luc, which contains the complete LCR fragment of the HPV-16 cloned in front of the luciferase gene were grown to about 50-60% confluence. Cells were treated with 2 μM and 4 μM 5-azacytidin for 24 and 72 hs. The addition of 5-azacytidine to the cells decreased the activity of the early p97 promoter in a dose dependent manner.
As shown in FIG. 9 , when undifferentiated or differentiated cells were treated with 2 μM 5-azacytidin, the p97 promoter activity was reduced to 40-60%). In both cells treated with 4 μM 5′-Azacytidin, the promoter activity was significantly reduced to the basal level.
These data show that application of 5-aza-cytidine as an example for a demethylating agent results in substantial inhibition of the activity of the HPV 16 URR. It therefore has a great potential to block the viral life cycle as well as to prevent the switch from acute to transforming HPV-infections. Based on these data such agents can be used to prevent replication to the virus, and its progression into higher grade dysplasia or even cancer. | The invention relates to compounds and methods useful in detection and therapy of HPV-associated diseases. The invention is based on the elucidation of a mechanism by which replication of HPVs occurs in naturally infected tissues and cells. Moreover it is based on the identification of distinct epigenetic changes of the viral genome in infected cells that allows promotion of the affected cells to precancerous and cancerous cells. The invention therefore provides methods of diagnosing neoplasias and their precursor lesions as well as methods of preventing the development of malignancies or inhibiting tumor growth. | 2 |
SUMMARY OF THE INVENTION
The present invention relates to a prefabricated fireplace unit which is adapted for installation in the wall of a home or similar building.
Conventional fireplaces suffer from a number of deficiencies. Since they are ordinarily fabricated by hand from bricks or the like, they involve a large amount of hand labor. In contrast, the fireplace of the present invention is completely fabricated in a factory so that it can be merely slid into place in a suitable opening in a home and connected to a flue and an air inlet.
Another deficiency of normal fireplaces is that they have a tendency to build up soot or creosote deposits in the chimney or spark arrestor which creates a fire hazard when the chimney finally burns out. In accordance with the present invention this difficulty is solved by providing outlets for a portion of the combustion air near the top of the fireplace which results in secondary combustion and the elimination of soot or creosote deposits in the chimney.
Another purpose of the present invention is to provide a fireplace having a minimum amount of weight and this, in part, is achieved by providing air ducts within curtain walls of the firebox, greatly reducing the amount of refractory material required and, thus, the weight of the fireplace.
Another feature of the present invention is that it provides two completely different paths for combustion air and room air. The combustion air is drawn from the outside of the building so that it is not necessary to consume and waste the heated room air for combustion. Further, since entirely separate paths are provided for the room air and the combustion air, coupled with the fact that the fireplace itself is virtually airtight with respect to the room, warm air is not drawn from the air in the room at any time. Many fireplaces result in an actual loss of heat to the building due to sucking warm air from the room, particularly as the fire is dying down. As will be later apparent, this is substantially impossible with the fireplace of the present invention.
Another feature of the present invention is that the front air inlet is easily opened giving access to one or more fans which are optionally located within the room air intake.
A further feature of the present invention is that the combustion air is drawn from the bottom of the fireplace and travels a substantial distance over the floor of the fireplace, reducing the need for refractory material.
Other features and advantages of the invention will be brought out in the balance of the specification.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a fireplace embodying the present invention.
FIG. 2 is an enlarged perspective view of the fireplace showing some of the parts in section.
FIG. 3 is a front elevation of the fireplace, partly in section.
FIG. 4 is a side elevation showing the parts in section.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings by reference characters, the fireplace of the present invention is generally designated 5 and comprises a metal shell having a top wall 7, a back wall 9 and side walls 11 and 13. Located within the chamber thus formed is a firebox designated 15 having a top member 17 having walls tapering to a flue opening 19 and flue 20 and having side members 21 and a back member 23. The firebox also has a bottom number 25 and the back members 23 and the bottom 25 are lined with a refractory material 27 and 29. The outer shell of the fireplace, which was designated 5, has a double-wall construction at the sides and the top with an insulating material 29 filling the space between the double walls. This leaves a chamber between the firebox and the outer shell at the back, top and sides of the firebox.
The bottom of the fireplace is designated 31 and this has a central opening 33 wherein combustion air can be brought from the outside of the structure. Suspended above the bottom 31 is a partition 35 leaving a space 37 between the partition and the floor of the firebox. As can be seen, this space 37 extends completely under the floor of the fireplace so that the flow of combustion air keeps the fireplace cool so that a minimum of refractory material is needed on the bottom.
At each side of the firebox are baffle plates 39 and 41 and, as can best be seen in FIGS. 2 and 3, an airspace 43 is left between the side 21 and baffle 39 and a similar space, not shown, on the opposite side. Mounted at the front of the firebox is the air passage 45 and this has a plurality of holes 47 which open at the front of the fireplace and two holes 49 and 51 which open into the space 43 and the corresponding space on the opposite side. Baffles 39 and 41 do not extend completely to the top of the firebox, but there is a gap 53 at the top thereof.
Two dampers are provided. First an inlet damper 55 having a shaft 57 and handle 58 extending to the front of the fireplace, while the flue opening 19 has an outlet damper 59 having a shaft 61 and handle 62 also extending to the front of the fireplace.
Thus, the combustion air enters through the air inlet 33 wherein air is drawn from outside the room, passes the damper 55 and into the plenum 37 and the air passage 45. Here most of the combustion air is discharged through the openings 47 at the front of the fireplace so that most of the air passes up over the front doors of the fireplace, keeping them cool and clean and ensuring that combustion takes place in the front. However, a small amount of the fresh combustion air goes through the passages 49 and 51 into the space 43 where it is discharged at the top of the flames as at 53 for secondary combustion. This provision of extra air for secondary combustion ensures complete burning and prevents buildup of creosote in the chimney.
At the front of the fireplace near the bottom thereof is a removable plate 63 having a plurality of louver openings 65. Air which enters through the louvers goes into the passage 67 which is formed between the bottom of the firebox 25 and the bottom of the fireplace 31 where it can pass through the passages 69 at the sides of the fireplace and 70 at the back of the fireplace and then passes through the passage 72 at the top of the firebox and, thus, the heated air is discharged through a grill 74. It will thus be seen two entirely separately passages for air are provided. The first is a passage for combustion air from an outside source through two different routes in the firebox and out through a flue 20 and a second path for room air which is drawn into the louvers 65 passes over the sides, back and top of the firebox and is discharged from the grill 74. It should be particularly noted that there is no mixing of the combustion air and the room air.
The front of the fireplace is provided with accordian glass doors 77 which have handles 79 thereon. These accordian doors are substantially airtight so that no heat is lost from the room up the chimney, even under conditions where the fire is very low. The doors may be equipped with handles 79 and these will stay cool since the combustion air is largely introduced at the front of the firebox where it flows over the doors keeping them cool and clean.
In the embodiment shown the fireplace is illustrated as having been installed on a brick hearth 81, but this is purely for aesthetic reasons as the bottom of the fireplace is well insulated by the air passages for both the room and combustion air and the refractory 29. Thus there is no practical reason why the fireplace cannot be installed directly on a combustible floor.
Normally the fireplace of the present convention gives good circulation purely by convection, but if desired one or more blowers 83 can be installed in the air inlet passages 67. Since the front plate 63 is removable, it is easy to install and service the blowers.
Preferably upstanding flanges are provided at the top and sides of the fireplace as at 85 and 87. These are not required for insulation, but instead are merely used as guides for the builder to establish the correct dimensions for the opening in which the fireplace is installed and to hold it firmly in place.
Although a preferred embodiement of the invention has been shown, it will be understood that many variations can be made in the structure shown without departing from the spirit of this invention. | A prefabricated fireplace, largely made of metal, is provided for permanent installation in a house or similar structure. The fireplace is completely self-insulated so that it does not require any special materials of construction for installation and furthermore, combustion air is supplied for secondary combustion to prevent creosote buildup. Additionally, the fireplace does not use room air for combustion and is substantially airtight so that no room heat is lost up the chimney. | 5 |
CROSS-REFERENCE TO A RELATED APPLICATION
[0001] This application is a National Phase Patent Application of International Patent Application Number PCT/DE2005/000769, filed on Apr. 22, 2005, which claims priority of German Patent Application Number 20 2004 007 054.5, filed on May 03, 2004.
BACKGROUND
[0002] The invention relates to a motor vehicle door with a side window.
[0003] A motor vehicle door with a side window which may be raised and lowered and a front, fixed side window, is known from EP 1 201 862 A1. A cable window winder is arranged in the door body, by means of which the side window may be completely lowered into the door body. No window winder is associated with the front window part, so that said window part may not be lowered.
[0004] In such a window winder system, the window is only able to be completely lowered when the door body has a minimum size. Even with sports cars or convertibles, the door bodies are, however, often small, so that the window is not able to be completely lowered.
[0005] Doors are also known in which the window region is releasably attached to the door body and, if required, able to be removed manually and carried in the vehicle. This, however, requires manipulation and carrying the window parts restricts the available luggage space.
SUMMARY
[0006] The object of the present invention is to develop a motor vehicle door, such that without additional manual handling, the side window is able to be completely lowered.
[0007] It is provided according to the invention that the window is of split configuration, that a separate window winder is associated with each window part, by means of which the respective window part may be completely lowered in the door body, and that, in the closed state, the window parts are held in contact with one another by the force of a spring. The window is preferably split into two parts, the split being created by a substantially horizontally extending line.
[0008] According to a preferred embodiment of the invention, window winders comprising slide and/or guide rails are used. The window winder associated with the lower window part, cooperates with the lower edge of this window, the winder cooperating with the upper window grips said upper window on the outer regions of the window lower edge and/or in a side region, which is enclosed by a window guide located above the door body. The guide rails and/or tracks of the window winder are designed, therefore, such that the window parts are lowered into the door body through a single slot arranged on the upper edge of the door body and are located parallel and adjacent to one another in the door body itself.
[0009] In an embodiment of the invention, firstly the lower window part is lowered and completely moved into the door body. Subsequently, the window winder associated with the upper window part is activated, which then moves this window into the door body. The reverse sequence is carried out to close the window region.
[0010] Firstly, the upper window is moved in this case into its end position, and then the lower window part, until the upper edge thereof comes into contact with the lower edge of the upper window.
[0011] In a preferred embodiment of the invention, the upper window part is received on the outer edges in window holders. For moving the window holders, drivable control cables are tensioned along the guide rails which act via driving units on the window holders and which, in turn, are mounted in guide rails.
[0012] By means of each compression spring associated with the front and rear combined driving unit-window holder, the upper window part is held relative to the driving units coupled to the cables in a lowermost position. Counter to this spring force of the spring arranged in the front and rear combined driving unit-window holder, the upper window part may be pressed further upwards by a predetermined distance. The spring force thus determines the sealing of the impact region between the edges of the upper and lower window part and, after switching off the window winder drives, the window parts remain sealingly in contact with one another, even with a possible yielding of the transmission elements.
[0013] With appropriate dimensioning of the path over which the window holder, next to the upper window part, may be moved counter to the spring force, relative to the driving unit coupled to the drive cable, the upper window part may be moved a small distance upwards by means of the drive of the lower window part. This results, on the one hand, in the secure sealing of the two window parts and, on the other hand, when closing a frameless door, the upper edge of the upper window part being able to be introduced into a sealing strip attached to the roof of the vehicle. Only the drive of the lower window part has to be controlled in this case and also for opening the door (lowering the window for releasing the seal—short stroke).
[0014] The window split according to the invention allows the complete lowering of a window region which is large compared to the door body. When the door bodies are cut away deeply downwards, such as for example with roadsters, no awkward window parts remain above the door body. Additional manual handling is also dispensed with, so that when using motor-driven window winders, comfortable operation results. By means of the spring elements between the window holders for the upper window part and the driving units, it is further possible to move the upper window part higher out of the door body than the arrangement of the deflection pulleys for the control cables allows. Thus the upper edge of the door body may be pulled a considerable distance downwards—the upper window part is only moved into the required end position by the lower window part during closing.
[0015] A further advantageous possibility in the application of the invention is created when the upper window part is introduced into the door body, the lower window part, however, still remaining stationary. The lower window part now functions as a splash guard.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Furthermore, the description of embodiments of the invention is made with reference to the figures, in which:
[0017] FIG. 1 shows a vehicle door with two window parts in the closed state.
[0018] FIG. 2 shows a vehicle door with two window parts in the opened state.
[0019] FIGS. 3-5 show the coupling of the window winder to the window parts.
[0020] FIGS. 6-8 show the arrangement of the driving unit, window holder and cable deflection pulley.
DETAILED DESCRIPTION
[0021] The vehicle door according to FIGS. 1 and 2 —the door is shown in an external view—consists of a door body 1 and a window region arranged thereover, consisting of a lower and an upper window part 2 , 3 . In the direction of travel, upstream of the window region, a mirror triangle 4 is located above the door body. Two window holders 5 , 6 are associated with the upper window part 3 , which bear the upper window part 3 on the front edge thereof and/or in the rear region on the lower edge thereof ( FIG. 3-5 ).
[0022] FIGS. 3-5 show the window winder arrangement for the two window parts 2 , 3 from the vehicle interior. The window holders 5 , 6 are displaceably coupled via driving units not shown in FIGS. 3-5 to a guide rail 7 , 8 located in the front region of the door body and a guide rail located in the rear region of the door body and thus form the window winder for the upper window part 3 . The rear window holder 6 , in particular, projects over the upper edge of the door body 1 and is adapted in its form to the design of the vehicle door ( FIG. 1 ).
[0023] FIG. 2 shows the vehicle door according to FIG. 1 in the opened state. As is shown in more detail below, firstly the lower and then the upper window part 2 , 3 is lowered and moved into the door body 1 . The region above the door body 1 is now windowless.
[0024] The lower window part 2 is received on its lower edge approximately centrally by a window holder 10 , which is attached to a path-controlled window winder 9 . The guideways of this window winder 9 are designed such that the lower window part 2 , according to the conditions and the spatial relations, is moved into and out of the door body 1 . In FIG. 3 the lower window part 2 is completely extended, in FIG. 4 a portion is retracted into the door body 1 , in FIG. 5 the lower window part 2 is lowered completely in the door body 1 by the window winder 9 .
[0025] The driving units 11 cooperating with the window holders 5 , 6 for the upper window part 3 may be moved via driven control cables 12 (not shown in FIGS. 3-5 ) along the slide rails 7 , 8 . When the lower window part 2 is lowered, the upper window part 3 follows said lower window part a certain distance, due to the spring forces between the driving units 11 and the window holders 5 , 6 (FIGS. 6 - 8 )—it is therefore lowered from the fully extended position according to FIG. 3 into the end position according to FIG. 4 , defined by the control cable system 12 , 13 . By controlling the drive associated with the window winder 9 , the upper window part 3 may now be fully retracted into the door body 1 . The slide rails 7 , 8 of the window winder of the upper window part 3 are designed according to the required inward and outward movement.
[0026] Closing the window is carried out by proceeding from the completely windowless situation according to FIG. 5 . Firstly, by controlling the corresponding drive, the upper window part 3 is moved into the end position according to FIG. 4 defined by the control cable system 12 , 13 ( FIGS. 6-8 ). The lower window part 2 is now moved upwards and thus the upper edge thereof is brought into contact with the lower edge of the upper window part 3 . Counter to the force of the springs between the window holders 5 , 6 and the driving units 11 ( FIGS. 6-8 ), the upper window part 3 is now pressed by the drive of the lower window part 2 into the upper end position. In this end position, therefore, the separating point between the two window parts 2 , 3 is sealed by the force of the springs 14 .
[0027] FIGS. 6-8 show the arrangement and the cooperation of the springs 14 between the driving unit 11 and the window holders 5 , 6 . The driving unit 11 for the upper window part 5 , 6 is coupled to a control cable 12 guided around a cable pulley 13 and may be moved via a drive, not shown, until in the end position defined by the position of the cable pulley 13 in the door body. This end position according to FIG. 6 corresponds to the position of the upper window part 3 in FIG. 4 —the lower window part 2 has no contact with the upper window part 2 . A compression spring 14 arranged between the window holder 5 , 6 for the upper window part 3 and the driving unit 11 coupled to the control cable 12 , holds the window holder 5 , 6 relative to the driving unit 11 in its lowermost position.
[0028] FIG. 7 shows the situation of the driving unit 11 , the compression spring 14 and the window holder 5 , 6 when the lower window part 2 is brought into contact with the lower edge of the upper window part 3 . A further upward movement of the lower window part 2 , therefore, causes the upper window part 3 to be lifted counter to the force of the compression spring 14 , the window holder 5 , 6 being therefore lifted from the driving unit 11 . The same effect is produced by lowering the lower window part 2 —by means of the compression spring 14 the window holder 5 , 6 again comes into contact with the driving unit 11 —the further lowering process then results by starting off the driving unit 11 via the control cable 12 .
[0029] It is not shown that the driving unit 11 of the upper window part 3 may be designed to be pulled a considerable distance downwards, and thus serves as centering for the lower window part 2 . By means of a fork-shaped configuration of the lower end of the driving unit 11 and the end oriented towards the lower window part 2 , the lower window part 2 approaching the lower edge of the upper window part 3 is oriented and thus precisely guided into the contact position provided. | The invention relates to a motor vehicle door with a side window, wherein a window winder being associated with the side window, by means of which the side window is able to be lowered in the door body. The side window is of split configuration, wherein a separate window winder is associated with each window part, by means of which the respective window part may be completely lowered in the door body. In the closed state the window parts are held in contact with one another by the force of a spring. | 4 |
BACKGROUND OF THE INVENTION
Many of the waste dump sites located throughout the U.S. and indeed, throughout the world, contain hazardous waste including toxic substances. Over time, such hazardous waste can enter the ground, for example with rainwater, and can come in contact with ground water beneath the dump site. Where this occurs, the ground water becomes contaminated.
Such ground water contamination renders the ground water beneath the dump site unusable. Normally, the ground water slowly flows beneath the dump site and thereby carries the contaminants which infiltrated at the dump site with it. Thus, a single dump can contaminate the ground water over large geographical areas far beyond the dump site. This renders the contaminated ground water unusable for most purposes or requires the installation of costly ground water treatment facilities where the hazardous contaminants are removed before the water can be used. As the flow spreads, increasingly large volumes of ground water become contaminated, thereby requiring increasingly large treatment facilities which are expensive to install and to operate.
Thus, efforts are being made to prevent hazardous waste from contaminating ground water flows by containing the contaminants at the dump site and preventing their escape therefrom. The U.S. Environmental Protection Agency (EPA) provides the following guidance for preventing the contamination of ground water flows in the "Remedial Action at Waste Disposal Sites" section of the EPA Handbook which, in relevant parts provides:
"Ground Water Controls"
"Control of ground water contamination involves one of four options: (1) containment of a plume; (2) removal of a plume after measures have been taken to halt the source of contamination; (3) diversion of ground water to prevent clean water from flowing through a source of contamination or to prevent contaminated ground water from contacting a drinking water supply; or (4) prevention of leachate formation by lowering the water table beneath the source of contamination."
"Remedial technologies for controlling ground water contamination problems are generally placed in one of four categories: (1) ground water pumping, involving extraction of water from or in injection of water into wells to capture a plume or alter the direction of ground water movement; (2) subsurface drains, consisting of gravity collection systems designed to intercept ground water; (3) low permeability barriers, consisting of a vertical wall of low permeability materials constructed underground to divert ground water flow or minimize leachate generation and plume movement; or (4) in situ treatment methods to biologically or chemically remove or attenuate contaminants in the subsurface. These technologies can be used singularly or in combination to control ground water contamination."
SUMMARY OF THE INVENTION
The present invention seeks to intercept the contaminated ground water flow in the vicinity, e.g., at the perimeter of the dump site, bringing it to the surface for treatment, that is for the removal of contaminants therefrom, and thereafter using the treated, contaminant-free water for other purposes including, for example, returning it to the ground at a point where it can no longer be contaminated. This involves the construction of a barrier downstream (in the direction of ground water flow) of the dump site, collecting the intercepted and contaminated ground water, and bringing it to the surface for appropriate treatment.
In the past, such barriers had to be constructed by digging sometimes very deep trenches, forming the required barriers and/or collection channels and thereafter closing the trenches. This is time-consuming and expensive work. In addition, it requires the removal of relatively large volumes of ground which is frequently contaminated with hazardous and/or toxic substances. This has two highly undesirable side effects.
First, digging contaminated ground exposes the workmen to the contaminants which is a serious health hazard. Secondly, the dug-up contaminated ground itself is hazardous waste which is difficult and expensive to dispose of and, if at all possible, should not be generated to begin with.
The present invention seeks to overcome the shortcomings encountered in the past by providing a barrier downstream of the dump site which is erected in situ by driving the barrier directly into the ground as contrasted with the heretofore common practice of first digging a trench. This is accomplished by constructing the barrier of a multiplicity of elongated sections or sheets which are individually driven into the ground by hammering, vibrating, water jetting or the like while adjoining edges of the sheet are interlocked in a substantially water-impermeable manner. The sheets are constructed so that the barrier forms generally horizontal, open channels which face in the upstream direction and which are fluidly connected with intermittent, spaced apart vertical conduits that extend from the bottom of the barrier to the top thereof above ground level. An appropriate filter material placed across the open channels and/or extending into the channels allows contaminated ground water reaching the barrier to enter the channels while keeping the surrounding ground, rocks, etc. out of the channel.
Water entering the channels flows according to prevailing pressure conditions through the channels and the vertical drain conduits. The water collecting in one or more of the vertical drains is pumped out of the drain to above ground for appropriate treatment to remove hazardous contaminants therefrom. After treatment, the water can be returned to the ground, at the downstream side of the barrier to prevent it from again coming into contact with hazardous contaminants from the dump site. Alternatively, it can be flowed elsewhere for appropriate use.
With the present invention, it is thus possible to drive a contaminated ground water flow barrier and removal system directly into the ground, that is without the need for excavating contaminated ground and thereafter appropriately disposing of it. This greatly enhances the safety of the installation procedure and significantly reduces costs. Thus, the present invention provides a safer and more cost-effective way for preventing the contamination of ground water flows by hazardous materials.
In its simplest form, the present invention contemplates the construction of a generally linear barrier immediately downstream of the hazardous waste dump site. Alternatively, the dump site can be partially or completely encircled with the barrier by constructing it, for example, in an L-shaped configuration or as an enclosing, square, rectangular or the like barrier.
The individual sheets which make up the barrier can be constructed of such materials as wood, concrete, steel or any other suitable material although, at the present and for cost reasons, their construction of wood is preferred. Generally speaking, each such sheet has a first longitudinal (vertical) edge which defines a groove and a second, opposite longitudinal edge which defines a tongue adapted to fit into the groove when two sheets are interconnected so as to form a vertical drain conduit between the bottom of the groove and the top of the tongue when two sheets are joined edge-to-edge.
The sheet further includes at least one and, if desired two or more horizontal channels which extend from the bottom of the groove at one longitudinal edge to the top of the tongue at the other longitudinal edge, that is across the full width of the channel. A center portion of the channel, that is a portion spaced from the longitudinal edges as well as from the top and especially from the bottom edge of the sheet is recessed into the side surface of the sheet which will face in the upstream direction upon installation to expose and open an upstream facing portion of the horizontal channel. Filter material is applied across the open side of the channel so that water can collect in the channel while surrounding ground is kept out of it. In a presently preferred embodiment of the invention, relatively rigid sheets or blocks, which are commercially available on the market, are used as filter material. By recessing the open portion of the channel, and thereby the filter material, damage to the latter while the sheet is driven into the ground from rubbing against the ground is prevented.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram of a dump site in which a contaminated ground water extraction system constructed in accordance with the present invention has been installed;
FIG. 2 is a side elevational view of two individual sections or sheets, constructed in accordance with the present invention, of which the ground water barrier of the present invention is made;
FIG. 3 is a plan view of the two sheets of the present invention shown in FIG. 2;
FIG. 4 is a partial, enlarged, side elevational end view of the sheet and is taken on line 4--4 of FIG. 2;
FIG. 5 is a partial, enlarged, cross-sectional view of a portion of a sheet and is taken on line 5--5 of FIG. 2; and
FIG. 6 is a partial, enlarged, cross-sectional view similar to FIG. 5 and illustrates another embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 schematically illustrates a dump site 2 which contains amongst others hazardous waste such as toxic chemicals, heavy metals and the like and where the hazardous waste lies on or is buried in ground 4. Some distance below ground level, ground water flows in the direction of arrow 6. A generally upright, vertical barrier 8 extends into the ground downstream (in the direction of ground water flow) from dump site 2. The barrier is generally transverse, e.g. perpendicular to the ground water flow, has an upstream side 10 and a downstream side 12 and extends from the surface into the ground to a depth sufficient to intercept the ground water flow. Typically, the barrier will extend to a depth where there is a substantially water-impermeable ground layer, e.g., a layer of clay, which defines the lower extent of the ground water flow immediately beneath the dump site. Under certain conditions, it may be sufficient if the lower edge of the barrier does not extend that far down and, instead, only extends into the ground water flow to a level beneath the contamination plume, that is to a level which is not reached by the contaminants.
Referring now to all drawings, barrier 8 is constructed of multiple, side-by-side sheets 14, the adjoining edges of which form substantially water-impermeable interlocks 16 including upright drain conduits 18 which have open ends 20 above ground. Each sheet has an elongated, generally rectangular configuration defined by a pair of spaced apart, elongated, vertical edges 22, 24, a top edge 26 and a bottom edge 28. For purposes further described below, the bottom edge includes a diagonal portion 30 which extends from one edge, e.g., edge 24 towards the other edge.
Side edge 22 of the sheet defines a groove 32 of a given depth and the opposite vertical edge defines a projecting tongue 34 of a height less than the depth of the groove. The tongue is configured so that it can extend into the groove when the sheets are side-by-side and interengaged. Since the height of the tongue is less than the depth of the groove, vertical drain conduits 18 are thereby formed at the interface between any two adjoining sheets.
A center portion 36 of the sheet, which is spaced from the sheet edges, is recessed relative to a remainder of an upstream facing (when installed in barrier 8) side 38 as is clearly illustrated in FIG. 2.
Each sheet includes at least one generally horizontally oriented channel 40 which extends from bottom 42 of groove 32 to the top of tongue 34. The channel is positioned and dimensioned so that it intersects the recessed surface portion 36 of the sheet and, therefore, the channel is open over the horizontal extent of the recessed surface portion. A sheet of filter material 44 is placed across the open portion of channel 40 by, for example, securing the sheet to the recessed surface portion.
In a presently preferred embodiment of the invention, sheet 14 is constructed of a plurality of wooden boards or panels as follows. A center board 46 is defined by upper and lower center board sections opposing edges 46a and 46b of which are spaced apart to define channel 40. A pair of first sideboards 48 are secured, e.g. nailed or bolted to the center board. The first side boards project past a longitudinal edge of the center board as is best illustrated in FIG. 3 so that the center board and the projecting portions of the side boards define groove 32 with the longitudinal edge of the center board defining groove bottom 42.
A pair of second side boards abut the first pair and they have a width less than the remaining width of the center board projecting to the right (as seen in FIG. 3) of the first pair of side boards to thereby define tongue 34. The side board on the upstream facing surface 38 includes a cutout which defines a recessed center portion 36 of the sheet. Typically, this board will be constructed of three sections, a top section 50a, a bottom section 50b and an interconnecting post 50c although the recess can be formed as well by sawing a cutout into the board.
In one embodiment of the present invention, filtration sheet 44 covers a surface area larger than the surface area of recessed center portion 36 and it is squeezed between opposing faces of side boards 48,50 on the upstream side 38 of the sheet to retain it in position. Alternatively, the sheet may have a configuration equal to or smaller than that of the center portion and can be directly secured to the underlying center board in any suitable manner such as by bonding, nailing, bolting or the like.
The type of filter sheet that is being used is best chosen to suit the conditions prevailing at the dump site. It may include perforated metal sheets, filter cloth or composite sheets and it is preferred that the sheet is relatively rigid. A filter material especially well suited and presently preferred is available under the trademark DRAIN-IT from Atlantic Construction Fabrics, Inc. of Richmond, Virginia. This filter material is a polyethylene filter fabric and provides for a high water flow through the filter while it keeps ground, sand, rocks and dirt out. DRAIN-IT filter fabrics are available in sheets ranging in thickness from a fraction of an inch to as much as 2" or more.
In an alternate embodiment of the invention, shown in FIG. 6, filter material is placed into channel 40, that is a rectangular block of filter material 52 substantially completely fills the cross section of channel to and extends from bottom 54 of the channel to its open end so that the filter is substantially flush with recessed center portion 36 of the sheet. DRAIN-IT filter material discussed above is particularly suitable for use in this manner because it permits water flow perpendicular to the face of the material as well as parallel thereto. Thus, when the sheet is part of barrier 8, ground water contacting the face of filter block 52 enters into the channel and then flows along the channel to one or the other of the adjoining vertical drain conduits according to the prevailing pressure conditions.
Center board 46 and side board pairs 48, 50 are suitably secured to each other by nailing, bolting, clamping, bonding or the like.
Sheet 14 can equally be constructed of other materials, such as concrete for example. When made of concrete, it is given substantially the same shape and configuration as the sheet illustrated in the drawings and described in greater detail above when constructed of assembled wooden boards. The filter sheet 44, or filtration block 52 can be cast with the concrete, where this is feasible. Alternatively, to prevent possible plugging of the filter material by liquid concrete, it is applied and secured to the concrete after it has cured.
In a presently preferred embodiment of the invention, the sheet has a width of between 20 to 24", a height as required to penetrate the ground to the desired level and an overall thickness of about 6". When constructed of assembled wooden boards, this means that boards of 2" thickness are used. The depth of groove 32 is selected to be 4", the height of tongue 34 is 2", so that the vertical drain conduit 18 has a dimension of 2"×2" while the width of recessed center portion 36 on the upstream side of the sheet is in the range of between about 6-10". Typically, the horizontal drain channel 40 has a width in the range of between 2-6" and a depth corresponding to the thickness of the center boards, in the illustrated embodiment about 2".
Turning now to the installation of a barrier constructed in accordance with the present invention, it is installed spaced from the boundary of dump site 2. A first, linear barrier 8 is formed by positioning a first sheet on top of the ground and orienting it so that it is substantially transverse to the ground water flow. The sheet is then conventionally driven into the ground with a hammer, a vibrator or by jetting water into the ground immediately beneath the lower edge of the sheet to fluidize the ground. The latter alternative is particularly suitable for relatively heavy, e.g., concrete sheets because once the ground beneath the sheet is fluidized, the weight of the panel will typically force it downwardly. To facilitate jetting water beneath the sheet, a water conduit (not separately shown) which extends from the top edge to the bottom edge may be incorporated in, e.g., cast with the concrete sheet.
Driving continues until the lower edge of the sheet has penetrated to the desired depth, e.g., to a water-impermeable layer of clay beneath the ground water flow. Thereafter, the second sheet is aligned with the already installed sheet by fitting tongue 34 on the just-installed sheet into groove 32 of the next sheet. While maintaining the fresh sheet aligned with the first sheet, it is driven into the ground until its top edge 26 is substantially flush with the top edge of the already installed sheet.
It will be noted that the diagonal bottom edge section 30 facilitates driving the sheet into the ground and, further, that it generates a lateral component force which biases the lower end of the sheet towards the already installed sheet, thereby maintaining the opposing tongue and groove connected and aligned. As a result, when the second sheet is fully installed, it forms a substantially water-impermeable interface at the joint between the two sheets and the two sheets define a vertical drain conduit 18.
The above-described procedure is repeated until the entire length of barrier 8 has been installed.
If desired, the barrier can be extended by including an L-shaped corner piece 56, which may be solid but preferably also includes a water flow channel (not separately shown) to interconnect the adjoining, perpendicular sheets, as well as the adjoining drain conduits 18. In addition, the corner piece includes a tongue and a groove shaped complimentary to the tongue and grooves on the sheets to form the required connection. An L-shaped barrier wall is preferable for those applications where there is danger of a lateral (in the direction of arrow 6) water flow to prevent contaminated water from escaping past the ends of the linear barrier.
At times, it is desirable to completely encircle the dump site 2 with a barrier 8 as is illustrated in FIG. 1. In such a case, the barrier, constructed and installed as above described, is rectilinearly extended to form a square, rectangular or the like barrier which completely surrounds the dump site.
Turning now to the operation and use of the barrier 8, ground water flowing beneath the dump site and contaminated with hazardous waste is intercepted by the barrier, i.e., the ground water flow impinges on the upstream side 10 thereof. The ground water flow drains into the horizontal channels 40 and flows along the channels into the vertical drain conduits 18. A suitable pump 62 connected to a drain pipe 48, which may either be the suction pipe of the pump (when the pump is located above ground) or the pressure pipe (when the pump is a sump pump, for example), pumps water from at least one vertical drain 18 to a ground water treatment facility 60 where the water is treated by removing and/or neutralizing hazardous contaminants therein. Once treated and contaminant-free, the treated water can be discharged, directly onto the ground on the downstream side 12 of the barrier, or it can be flowed via a suitable pipeline (not shown) to another site for use elsewhere.
As the pump 62 pumps water out of a given drain conduit 18, the water level therein drops, thereby creating a pressure head on the water in all remaining conduits and horizontal channels which causes the water therein to flow towards the drain conduit from which water is removed. As a result of the network of fluidly interconnected channels and conduits, water can be pumped out of any one or more of the conduits. This makes it also possible to accommodate installations with relatively greater or lesser ground water flows by installing a greater or lesser number of pumps as may be required. | A barrier for intercepting a flow of ground water flowing beneath a dump site holding hazardous waste seeping through the ground into the ground water flow. The barrier is formed of a plurality of side-by-side, interlocked wood, concrete, steel or the like sheets which are power driven directly into the ground without first forming trenches. The sheets define a network of horizontal, open channels which communicate with intermittent, spaced apart vertical conduits that extend over the height of the barrier and terminate in open ends. A filter material covers the open channels and is recessed relative to the lower edge of the sheet to prevent it from being damaged when the sheet is driven into the ground. Contaminated ground water flowing into the channels flows through them and the vertical conduits according to prevailing pressure conditions and is pumped from at least one of the conduits for treatment above ground and the removal of hazardous waste contaminants before the treated, hazardous waste-free water is returned to the ground at a location remote from the waste site, e.g., on the downstream side of the barrier. | 1 |
BACKGROUND OF THE INVENTION
Normally it is required that the forces acting on the gate operating ring of a horizontal turbine machine be equally distributed. However, there has been a demand for a counterweight arrangement for providing a closing force if fluid pressure to the gate ring operator of a bulb turbine is lost. In providing an effective counterweight for the gate ring, the large weight destroys the equal distribution of forces on the particular gate operating ring.
Turbine machine size has increased with a corresponding increase in the size of the gate operating ring having a much larger radius. Thus, a greater unequal distribution of forces are applied to the bulb turbine gate ring. The greater unequal distribution of forces upon the gate ring requires that gate ring servomotors must be oversized to counteract the increase in the weight of the counterweight in an opening movement.
SUMMARY OF THE INVENTION
In resolving the problem, it was conceived that if the counterweight was available only when needed, such as at the time of loss of fluid pressure to the servomotors, then the unequal distribution of forces to the gate operating ring would not be a problem. In other words, by providing an emergency closure device which would act on the gate ring only when needed, a reduction in servomotor size would result and a balance of forces on the gate ring will be possible.
It is a general object of the invention to provide a counterweight system which is only active in an emergency situation.
Another object of the invention is to provide a counterweight system which is automatically activated when required and deactivated when not required.
Still another object of the invention is to provide a counterweight system which utilizes a flow of water to provide the necessary weight for a counterweight system when needed.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a view partly in section and partly in elevation through a penstock showing a bulb turbine therein having the counterweight system of the present invention;
FIG. 2 is an enlarged sectional view through the bulb turbine taken in a plane represented by the lines II--II in FIG. 1, showing the gate ring, operating servomotors and the counterweight system of the present invention; and,
FIG. 3 is an enlarged fragmentary view of a gate linkage connecting the wicket gate to the gate operating ring.
DESCRIPTION OF THE INVENTION
As shown in FIG. 1, a bulb turbine generator unit 10 is supported by upper and lower stay columns 11 and 12, respectively. The machine includes a bulb portion 16 which is supported on a center pier 17 within the intake section 18 of a dam 19. Forward of the bulb 16 the machine includes a runner cone 21 located within the discharge ring 22 of the draft tube 23. A runner hub assembly 26 operatively supports a plurality of angularly adjustable runner blades 27 which radiate from the hub 26. A plurality of adjustable wicket gates 31 are supported by an inner gate barrel 32 and an outer gate barrel 33.
The angularly adjustable wicket gates 31 which control the flow of water to the runner blades 27 are positionable by operation of a gate operating ring 36. The gate operating ring 36 is movably supported on the outer gate barrel 33. The wicket gates 31 are operably connected in a well known manner to the gate operating ring 36 as shown in FIG. 3. As there shown, wicket gates 31 are provided with a stem 34 which receive a spacer hub 42. A lever arm 43 is keyed to the extending end of the gate stem and has its free end pivotally connected to a link 44. Link 44, in turn, has its opposite end secured to the gate operating ring 36. Thus, rotation of the ring 36 in a counterclockwise direction as viewed in FIG. 2 will serve to move the wicket gates 31 to closed positions. On the other hand, movement of the gate ring 36 in a clockwise direction as viewed in FIG. 2, will serve to open the gates.
Operation of the gate operating ring 36 is accomplished by means of a pair of servomotors 51 and 52 which are supported on brackets that are attached to the sidewalls 53 and 54 of the turbine gallery. As shown in FIG. 2, the gate operating ring 36 is positioned so that the wicket gates 31 will all be open. When the gates 31 are to be closed a signal will be obtained to cause the servomotors 51 and 52 to be energized to effect a retraction of their associated piston rods 56 and 57 within their associated cylinders 58 and 59. This will cause the gate operating ring 36 to be rotated in a counterclockwise direction, as viewed in FIG. 2, to thereby move the wicket gates to closed positions.
For emergency operation, in the event that fluid pressure to the servomotors 51 and 52 fail, or if the servomotors become inoperative for any reason, there is provided a counterweight system 60.
As shown in FIG. 2, the counterweight system 60 includes a fluid tank member 61. Tank 61 is suspended from a bracket 62 that is attached to the gate operating ring 36 by means of a rod 63. The tank 61 is provided with a fluid fill line 66 which communicates with the interior of the tank. (A control valve 67 is provided which may be a solenoid actuated valve for automatic operation or manual actuated valve.) A supply line 68 is connected to the inlet side of valve 67 for supplying fluid to the tank 61 when the valve is opened. At the lower end of the tank 61 there is provided a drain line 71 which is connected to a flow control valve 72. The outlet of the control valve 72 is in communication with a drain line 73.
In operation a loss of fluid pressure in the servomotors 51 and 52 will be detected by an alarm system (not shown). This will result in a signal being generated to energize the solenoid of valve 67 to open the valve. As a result, fluid will flow into the tank 61 filling the tank. As the fluid flows into tank 61, the weight of the fluid will effect rotation of the gate operating ring 36 in a counterclockwise direction, thereby effecting the movement of the wicket gates 31 to a closed position. With the gates closed, the solenoid of valve 67 will be deenergized to condition the valve to stop fluid flow to tank 61. After the emergency has been corrected, the solenoid of valve 72 will be energized by another signal and valve 72 will be energized to condition the valve to open allowing the tank to drain. After the tank has drained another signal is obtained to deenergize the solenoid of valve 72 to condition the valve to a closed position and the emergency cycle is complete.
With the present invention, a constant unequal force of a counterweight is not applied to the gate operating ring 36. Thus, the ring structure need not be oversized to accept such unequal force nor do the servomotors need to be oversized to counteract the constant applied counterweight mass. The counterweight herein disclosed is only applied to the gate operating ring 36 in response to an energency. | A fluid container associated with the wicket gate operating ring to receive fluid from a source so as to add an emergency counterweight to the gate operating ring upon failure of the gate operating ring servomotors. | 5 |
FIELD OF THE INVENTION
The present invention relates to methods and apparatus for producing strip-like or foil-like products from metallic or metallic oxide material wherein a metallic or metallic oxide melt from a storage container is applied through a nozzle opening onto the surface of a cooler moved at a regulated speed.
BACKGROUND OF THE INVENTION
A method and an apparatus for producing amorphous metal strips are known (e.g., European Patent No. 0,026,812), wherein a metallic melt from a storage container is forced from at least one nozzle opening and is solidified on the surface of a cooler moved past and in the immediate vicinity of the nozzle opening. When circular nozzles with a diameter of 0.5 to 1 mm are used for producing amorphous metal strips, there is an optimum relationship between the nozzle opening, the distance between the nozzle opening and the cooler surface, and the speed of the cooler surface. This permits the production of uniformly formed metal strips at high production speeds. Such strips can either be completely amorphous or have a two-phase amorphous/crystalline mixture. The term amorphous metal alloy means an alloy whose molecular structure is at least 50 percent, and preferably at least 80 percent amorphous.
Another method and apparatus for producing a metal strip are disclosed in German Patent No. 2,746,238 where various nozzle shapes, which are complicated to manufacture, are used for the production of "wide" metal strips. The greatest strip width obtainable is 12 mm. Within the system a plurality of parallel, uniform nozzle jets must strike a moving substrate from a suitable distance, e.g., to obtain relatively wide strips. However, testing of this system has led to difficulties, particularly since the nozzle jets do not combine to form a pool and it is very difficult to obtain strips with a uniform cross-section. It is also difficult, if not impossible, to obtain a pool with an adequately uniform thickness for drawing strips wider than about 7.5 mm with an approximately uniform cross-section.
To overcome these difficulties, German Patent No. 2,746,238 proposes devices with stepped nozzle shapes located very close to the cooler surface. The system permits production of strips with more uniform thicknesses, widths, and uniform strength characteristics, up to the range of the aforementioned widths.
In conjunction with an apparatus for producing metal strips at a high speed, a nozzle body with a curved surface and a slot-like nozzle opening is known for influencing the flow conditions between the nozzle body and the cooler surface (e.g., European Patent No. 0,040,069). The strips produced in this way mainly have an amorphous structure. Although coating of the cooler surface with different materials is described, it is used exclusively to obtain specific physical surface properties, particularly completely satisfactory and easy detachment of the produced strips from the cooler surface.
Finally, British Patent No. 2,083,455 discloses a drum-like cooler with a circumferential slot. The circumferential slot on the drum, to a certain extent, serves as a mold for a relatively thick metal strip which can be subsequently cut at right angles to form small disks, as are conventionally used in the manufacture of semiconductors.
The conventional methods and apparatus for producing strips of the aforementioned type suffer from an important disadvantage in that they cannot, in a practical manner, produce strips significantly wider than about 15 cm, despite a very considerable need for such strips. Heretofore, such strips could only be produced by complicated and cost-intensive rolling processes. Wider strips with an amorphous structure are needed, e.g., for the production of transformers. Such transformers have approximately 30% lower magnetic reversal losses than conventional stacks of sheets.
Further, known methods and apparatus for producing strips of the aforementioned type are used exclusively for producing strips with homogeneous structures. Conventional methods or apparatus are not used for producing strips having juxtaposed areas with different metallurgical structures, or different geometrical structures. There is a considerable need for such strips, e.g. for packaging foils, which heretofore had to be produced by the more complicated and cost-intensive rolling process, and for mass-produced products, particularly small parts, from strip or foil material, which heretofore had to be stamped or punched out of closed foils or strips. The stamping or punching process is also complicated and costly.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a method and an apparatus for producing strip-like or foil-like products from metallic material or metallic oxide material with any random width and with separate areas of different structures (e.g., amorphous or crystalline).
Another object of the present invention is to provide a method and apparatus for producing strip-like or foil-like products with adjacent areas of different metallic and/or geometrical structures.
The foregoing objects are obtained by a method for producing strip-like and foil-like products from metallic material and metallic oxide material, comprising the steps of applying a material melt from a storage container through a plurality of juxtaposed nozzle openings onto a cooler surface, combining the melt from each nozzle opening into a closed melt upon contacting the cooler surface, solidifying the melt at the instant of combining, and moving the cooler surface at a regulated speed. The method produces a closed material layer of predetermined width.
The foregoing objects are also obtained by an apparatus for producing strip-like and foil-like products from metallic material or metallic oxide material, comprising a storage container, a cooler surface movable at a regulated speed, and a plurality of juxtaposed nozzle openings. The nozzle openings are coupled to the storage container and oriented relative to the cooler surface such that action ranges of the nozzle openings directly contact one another on the cooler surface.
The foregoing objects are further obtained by a method for producing strip-like or foil-like products from metallic material and metallic oxide material, comprising the steps of applying a material melt from a storage container through a nozzle opening onto a cooler surface and moving the cooler surface at a regulated speed. Solidification of the melt on the cooler surface is controlled by regulating conditions on the cooler surface such that different surface areas of the cooler surface have different conditions. After solidification of the melt, the solidified product is removed from the cooler surface.
The foregoing objects are additionally obtained by an apparatus for producing strip-like or foil-like products from metallic material or metallic oxide material, comprising a storage container, a nozzle opening coupled to the storage container and a cooler surface movable at a regulated speed. The cooler surface has a plurality of surface areas spaced along a perpendicular to the direction of cooler surface movement. The surface areas have different thermal conductivity characteristics.
The method and apparatus of the present invention overcome many of the previously experienced difficulties and the disadvantages associated with conventional systems. The present invention permits production of strips of almost any width and with separate areas of different structures (e.g. amorphous or crystalline), thereby facilitating a wide range of uses. For example, a foil can be produced having an amorphous structure in its central area, so that the central area is rigid and dimensionally stable or permeable or impermeable to air as required, while the edge areas have a soft and flexible crystalline structure permitting connection to other elements, e.g., by folding. The combined control of the method parameters for juxtaposed nozzles or nozzle groups permits determining, in an advantageous manner, the material characteristics of the strips to be produced.
Strips produced by this system can be used in a particularly advantageous manner for cladding or lining mechanically or chemically stressed parts, e.g. pipelines, to make them corrosion-proof, or to provide friction bearings. When using strips or foils produced according to the invention, such articles can be manufactured more simply and cheaply than when produced by traditional methods. In addition, the products produced according to the proposed system have better technological properties than conventionally produced products, e.g. by power-metallurgical methods.
According to a particular form of the invention, the cooler surface is segmented, perforated or profiled to define geometrically bounded areas. Such cooler surface can produce foils with a structured surface and with shape or form-limited individual areas. Thus, it is possible, in a simple and appropriate manner, to mass produce small parts from strip or foil material.
Other objects, advantages and salient features of the present invention will become apparent from the following detailed description, which, taken in conjunction with the annexed drawings, discloses preferred embodiments of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
Referring to the drawings which form a part of this disclosure:
FIG. 1 is a diagrammatic perspective view of an apparatus according to the present invention;
FIG. 2 is a partial front elevational view of a first embodiment of a nozzle body with several individual slots, while FIG. 2a is a sectional view taken along line S--S of FIG. 2;
FIG. 3 is a front elevational view of a second embodiment with a slot nozzle formed from individual nozzles, while FIG. 3a is a sectional view taken along lines U--U of FIG. 3;
FIG. 4 is a side elevational view of a third embodiment with displaced individual nozzles and separate nozzle bodies;
FIG. 5 is a top view of the apparatus of FIG. 4;
FIGS. 6A and 6B are bottom plan views of a nozzle body with displaced nozzle slots;
FIGS. 7A to 7C are bottom plan views of nozzle modules with a through nozzle slot;
FIGS. 8A to 8C are bottom plan views of nozzle modules with displaced nozzle slots;
FIGS. 9A and 9B are bottom plan views of nozzle modules with sloping nozzle slots;
FIG. 10 is a side elevational view of an apparatus according to the present invention;
FIG. 11 is a front elevation view of a preferred embodiment with several storage containers, for producing a strip or foil with juxtaposed areas of different materials or qualities;
FIG. 12 is a plan view of a cooling drum with a segmented surface structure;
FIG. 13 is a sectional view of the drum according to FIG. 11;
FIG. 14 is a plan view of a cooling drum with a perforated surface structure;
FIG. 15 is a sectional view of the drum according to FIG. 14;
FIG. 16 is a plan view of a cooling drum with a profiled surface;
FIG. 17 is a sectional view of the drum according to FIG. 16;
FIG. 18 is a sectional view of another embodiment of the cooling drum;
FIG. 18a is an enlarged view of a portion of FIG. 18; and
FIG. 19 is a plan view of the embodiment according to FIG. 18.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The apparatus of the present invention, as diagrammatically illustrated in FIG. 1 comprises a continuously rotating drum 1, which drum acts as a cooler, storage containers 2 with one or more nozzles 3 (e.g. with one nozzle slot), and an induction heater 4 for heating the melt in the storage containers 2. Any other suitable temperature-stabilizing device can be used in place of the induction heater.
The storage containers 2 contain a molten metal, which is optionally supplied from a source 5. The storage containers 2 and the complete apparatus can be connected to an inert gas system, which is diagrammatically indicated in FIG. 1 by a gas container 6 connected to the storage containers 2. The area of the nozzle opening can also be surrounded by a protective gas atmosphere or be enclosed in a vacuum. To avoid possible unwanted influences of the boundry layer, the nozzle outlet can be covered with electrostatic fields. The storage containers 2 can be subjected to the action of a slight overpressure from gas container 6. Other devices for producing a pressure difference between a storage container and the nozzle openings can be used, e.g. known mechanical or electromagnetic pressure difference generating means. A regulated power supply means 7 is connected to induction heater 4. For the better detachment of the formed strip 8 from drum 1, a stripper nozzle 90 for air or protective gas connected to a reservoir 100 can be provided.
In the illustrated embodiment of FIG. 1, the nozzle configuration 3 comprises a plurality of individual nozzles as described hereinafter. Essentially, a distinction is made between two construction types, which can be combined with one another. In a first construction type, as shown in FIG. 2, a single nozzle body integrated with the storage container 2 is provided which nozzle body has three individual slots 3A, 3B, 3C. In a second construction type, which is diagrammatically shown in FIGS. 3, 4 and 5, a plurality of nozzle bodies are provided having either individual nozzles 3 or nozzle groups 3A, 3B, 3C and being connected to separate storage containers 2A, 2B, 2C.
The slotted nozzle 3, comprising nozzle openings 3A, 3B, 3C according to FIGS. 2 and 3, extends at right angles to the movement direction Y of drum 1 and substantially parallel to the drum surface. Nozzle openings 3A, 3B, 3C are juxtaposed such that the molten metal flowing out of the storage container 2 or storage containers 2A, 2B, 2C forms a continuous, closed melt on the surface of drum 1 acting as a substrate. Drum 1, constructed as a cooler, produces a temperature drop in the melt coating causing immediate solidification of the melt and formation of a mechanically closed material web on the substrate. Through the selection of the melt temperature, e.g. with the aid of a regulatable power supply means 7, the selection of the movement speed of drum 1 and the selection of the temperature gradients on the substrate surface, it is possible to produce material webs having different structures, i.e. mainly an amorphous or a crystalline structure. Such crystal structures can be determined on the finished product, e.g. by X-ray diffraction measurements. Crystalline materials show characteristic sharp diffraction lines, while in amorphous material, the intensity of the X-ray diffraction pattern only changes slowly with the diffraction angle.
When using separate nozzle bodies connected to separate storage containers 2A and 2B, it is possible to produce material webs, which contain in juxtaposed manner an amorphous/amorphous or amorphous/crystalline structure. A foil produced in this way appears as a closed or mechanically unitary web, but in different areas has the known varying characteristics for crystalline or amorphous structure. For example, a foil produced in this way, is highly elastic and stable in the central area, and is soft and consequently easily deformable in the edge areas, so that it is eminently suited as a packaging foil. A more exacting field of use involves the production of juxtaposed and interconnected printed conductors with normal and superconducting regions on a foil. Such foils can be used in the production of high-field coils for fusion plants.
According to the embodiment shown in FIGS. 4 and 5, the nozzle heads and their separate storage containers 2A, 2B, 2C are displaced from one another in the movement direction Y of drum 1. Thus, the action areas of the nozzles or nozzle groups belonging to the individual storage containers follow one another in jointless manner at right angles to the movement direction Y of drum 1. This arrangement permits the production of different material webs which directly link regions of different material. The transitions between the regions are along sharp dividing lines. This is achieved by controlling the method parameters, the melt temperature, the spacing between the nozzles and the movement speed of the drum surface, such that a second melt, with a different composition and provided from the second storage container 2B, is directly melted on the already solidified melt from storage container 2A. This forms a unitary material layer, which can be removed as a single entity from the drum surface.
In order to obtain optimum connection regions between the nozzle openings 3A, 3B, 3C, it is particularly advantageous to reciprocally displace juxtaposed nozzle openings in movement direction Y (see FIGS. 6A and 6B). Such nozzle modules 8A, 8B, 8C can be used individually or positively juxtaposed in plural form on the bottom of a storage container 2. Such nozzle module contains several nozzle openings 3A, 3B, 3C with a slot width a, a slot length b, a displacement c and an overlap d'. This arrangement leads to particularly advantageous, uniform covering of the action areas of the nozzle openings. The following values have proved to be particularly advantageous: a=0.3 to 0.8 mm, b=20 to 100 mm, c=0 to 5 mm and d'=0 to 3 mm.
FIGS. 7 to 9 show further advantageous embodiments of such nozzle modules. According to FIGS. 7A to 7C, the juxtaposed nozzle modules have a through or continuous nozzle slot 3. According to FIG. 7A, the abutting surfaces between the modules are at right angles to the nozzle slot. FIG. 7B shows sloping abutting surfaces, which in practice leads to particularly good transitions between the individual nozzle modules, and which makes it virtually impossible to detect interfaces on the product produced. According to FIG. 7C, there are curved abutting surfaces between the modules, which particularly advantageously permit a self-centering mechanism for the through nozzle slot.
Each of the nozzle modules according to FIG. 8A contains a nozzle opening and sloping abutting surfaces. According to FIG. 8B, each module contains several, and in the specific embodiment, two displaced nozzle openings and sloping abutting surfaces between the modules. The nozzle openings are also displaced at the interfaces. However, the nozzle openings of FIG. 8C are continuous over the abutting surfaces which are at right angles to the nozzle slots.
FIGS. 9A and 9B show embodiments in which juxtaposed sloping nozzle openings overlap one another in such that the bent or extended ends of these openings overlap the adjacent nozzle module. In this manner, no special starting and finishing modules are required.
According to a preferred embodiment for producing an amorphous strip from the alloy Fe 40 Ni 40 B 20 , an apparatus according to FIGS. 1 and 2 was used in which a multiple nozzle arrangement had an overlap D of 1 mm, a displacement C of 3 mm, a nozzle slot width of 3 mm and a distance between the nozzles and the substrate surface of 0.3 mm. A casting speed of 1.2 km/min was obtained from a drum rotation speed of 1200 r.p.m. and a drum diameter of 30 cm.
According to a further embodiment in which a modular nozzle according to FIG. 7 was used, the size of the individual nozzle was 2.0×0.3×35 mm, with the distance between the nozzle and the substrate surface being 0.3 mm. The casting speed was the same as in the previous embodiment.
It has proved advantageous to select the distance d between the nozzles and the substrate surface so that it is larger than the thickness of the strip or layer to be produced, and is smaller than 0.5 mm. In order to produce amorphous strips or layers, a casting speed in the range 1.2 to 2.0 km/min has proved to be particularly advantageous for the aforementioned preferred embodiments. In the embodiment, strips with a width of 5 to 30 cm were produced.
By means of the described methods and apparatus, it is possible to produce in a particularly advantageous manner foils from, e.g. with Ni and Pd for catalytic reactions, Cu-Ti, Cu-Zr, Ni-Zr, and Mg-Nn alloys, e.g. for hydrogen reservoirs, as well as soldering foils based on iron for welding stainless steel and nickel alloys and for joining ceramics with metal parts. It is also possible to produce transformer plates or Ge-containing or Si-containing alloys for semiconductor purposes, or carrier material, e.g. silicon solar cells can be coated therewith. It is also possible to produce superconducting alloys in this way. According to the described system, high-quality foils can be held on the edges of less valuable transport materials permitting the mechanical working of such foils with the aid of transport means acting on the edge, while protecting the useful foil.
Using such products or the described method, it is possible to produce composite materials of the most varied types, e.g. different metal alloys in sandwich form, or with the isostatic moulding of fibrous materials, strips and the like. Using the foils or strips produced by the method and apparatus according to the invention, it is also possible to clad or line pipes or transport lines so that they have a corrosion resistant surface of high-quality material, while the carrier material can be a simple, inexpensive mass-produced product.
Large-area coatings of this type can be achieved by several abutting material webs. The abutting regions between the juxtaposed material webs are subsequently treated in a subsequent operation such that a homogeneous surface of uniform thickness is obtained. The additional step can, for example, be performed with the aid of laser glassing. The material coatings in the abutting regions are briefly and locally melted to an adjustable penetration depth. The cooling potential of the surrounding material is sufficient to permit the solidification, in glass-like manner, of the melted-on volume with very high cooling rates, e.g. in the range of 10 4 and 10 5 °C./sec so that once again an amorphous material structure can be produced. By means of this method, it is possible to upgrade the surfaces of pipes or shafts. Workpieces with relatively large dimensions can also be provided with age-hardened or hardened surfaces.
The apparatus shown in FIG. 10 comprises a continuously rotating drum 1 acting as a cooler, a storage container 2 with at least one nozzle opening 3 and an inductive heater 4 for heating the melt in storage container 2. Nozzle opening 3 is at a distance d from the surface of drum 1. Storage container 2 contains a molten metal, or a metal alloy or metallic oxide, which is optionally supplied from a source 5. Both the storage container 2 and the complete apparatus can be operated as a pressure or inert gas system, which is diagrammatically indicated in FIG. 1 by a pressure container 6 connected to storage container 2. A regulated power supply means 7 is connected to the induction heater 4. The melt flowing from storage container 2 forms a thin melt coating on the surface of drum 1 acting as a substrate.
When using separate storage containers 2A, 2B, 2C according to FIG. 11, individual storage containers 2A, 2B, 2C can contain different metals or alloys which solidify to a unitary strip on drum 1.
According to the embodiment of FIG. 11, three cooling means 8A, 8B, 8C supply the drum 1 in areas 1A, 1B and 1C with a fluid coolant, e.g., air or inert gas. By the selection of suitable cooling capacities with the aid of cooling means 8A, 8B and 8C, it is possible to produce different temperature ranges on the drum surface in areas 1A, 1B and 1C. The melts flowing out of storage containers 2A, 2B and 2C are therefore quenched to a varying degree on striking the drum surface so that a desired crystal structure can be obtained on any one of the drum areas 1A, 1B and 1C within the resulting closed material web.
The aforementioned system also makes it possible to produce a closed or unitary material web from juxtaposed areas of different materials. The corresponding melts of the desired materials fill storage containers 2A, 2B, 2C and coat and drum surface forming a joint-free closed web with juxtaposed areas of different material. The cooling conditions on the drum surface are set by cooling means 8A, 8B, 8C using known criteria. In this manner, the solidification conditions on the drum surface are adapted to the selected removal rate, i.e. to the rotation speed of the drum.
According to FIGS. 12 and 13, the drum surface is provided with separating ribs 9A, 9B, 9C which separate intermediate substrate regions 10A, 10B. Foil segments formed in substrate regions 10A, 10B are only slightly separated from one another in the vicinity of the separating ribs 9A, 9B, 9C, so that the resulting strip-like material can be removed from the drum 1 as an entity and the segments can be easily separated from one another in a subsequent processing stage, e.g. during the final working of the foils.
According to the embodiments shown in FIGS. 14 and 15, perforations 11A, 11B, 11C are provided in the drum and can have random configurations. The perforated regions on the drum surface are not wetted by the applied melt so that there are corresponding recesses in the resulting strip-like material. This obviates the conventional additional process stages, such as stamping or punching. Thus, a high degree of further processability is achieved directly at the time of the production of the foils or strips. Alternatively, projecting areas, instead of recesses, can be formed on the drum surface so that the resulting strip-like material has a corresponding shape.
The embodiment according to FIGS. 14 and 15 also makes it possible to combine different materials or material characteristics in juxtaposed areas.
In the embodiments shown in FIGS. 16 and 17, the cooling drum surface has profiles 12A, 12B, e.g. rib profiles. These ribs, unlike the embodiment of FIGS. 12 and 13, have smooth transitions so that the ribs are uniformly coated by the melt and a corresponding foil-like or strip-like material forms. Such a material is used as a top-quality semifinish product, e.g. in the production of catalyst foils in chemical engineering.
In embodiments according to FIGS. 18 and 19, the drum 1 has uniformly spaced transverse grooves 13. When using a fine nozzle opening 3, the grooves will produce material fibers whose length corresponds to the spacing between the transverse grooves. In the present embodiment, drum 1 has a diameter of 280 mm. The fiber length of 2 cm was obtained by segmenting the drum in 2 cm spacings. The V-shaped transverse groove 13 has a depth of 1 mm and an angle of 60°. The drum rotation speed is 1500 r.p.m., corresponding to a casting speed of 1.32 km/min. The nozzle used has a 0.5 mm diameter hole, while the distance d between the nozzle opening and the drum was approximately 2 mm. The embodiment was carried out with a Fe 40 Ni 40 B 20 alloy. Typical fiber dimensions are width 0.5 mm, length 20 mm and thickness 30 μm.
Such short fibers made from metallic glasses can be used for reinforcing plastics, ceramics or cement. They also form a starting material for molding and sintering in the production of compact, glass-like or finely crystalline workpieces.
In a modified embodiment, the nozzle opening 3 can be in the form of a slot to produce wide foil pieces. A slot nozzle with a width of 20 mm was used. The distance d was approximately 0.3 mm. The alloy used was Fe 40 Ni 40 B 20 . The dimensions of a foil piece were width 20 mm, length 20 mm and thickness 60 μm.
According to another embodiment for producing profiled strips or strip portions according to FIGS. 16 and 17, the drum 1 had a diameter of approximately 320 mm. The drum surface was provided with a slightly rounded longitudinal profile of width 1.5 mm and a projection of 0.2 mm. The speed of revolutions was 1500 r.p.m.
The nozzle used had a nozzle opening width of 9 mm. The distance between the nozzle opening and the profile surface was 0.3 mm. Typical values for the dimensions of the strip with profiled cross-section were, according to FIG. 11, width 9 mm, thickness at the ends 45 μm and thickness in the center 35 μm.
According to another embodiment, the previously produced foils and other semifinished products were coated several times using the aforementioned method. A semifinished product was obtained with several coatings of different materials or different crystal structures. For example, the drum 1, serving as a cooler, and which constituted the substrate for the strips or coating to be produced, was replaced by a suitable semifinished product, e.g. a pipe or other workpiece. The semifinished product can be coated with the aid of the described apparatus and method. While maintaining a continuous drawing speed,the semifinished product to be coated is moved under the nozzle body and cooled as a function of the material properties or thermal conductivity characteristics of the semifinished product used as the substrate. The coating with the desired crystal structure (crystalline or amorphous) is formed on the surface. Pipes with an amorphous coating produced in this way have a particularly high degree of corrosion resistance with the appropriate choice of coating material. They can be used with particular advantage in the manufacture of chemical apparatus. They are much less expensive than conventional solid material pipes for this purpose, because simple, inexpensive material can be used as the semifinished product.
While various embodiments have been chosen to illustrate the invention, it will be understood by those skilled in the art that various changes and modifications can be made therein without departing from the scope of the invention as defined in the appended claims. | Juxtaposed nozzle openings apply the same or different melts to the surface of a moving cooler surface for producing thin metal strips or foils with a considerable width. The nozzle openings can be staggered in the direction of movement of the cooler surface and apply different materials to produce a metal strip with juxtaposed and sharply defined regions with different characteristics. Amorphous or mixed amorphous/-crystalline, or solely crystalline material structures can also be produced. Alternatively, different cooling capacities on different cooler surface areas and different structuring of different cooler surface areas permit the melt to solidify on the cooler surface such that the strips or foils obtained have adjacent regions with different metallic and/or geometrical structures. By geometrical configuration of the cooler surface, foils with a structured surface or with shape-limited individual regions can be used for mass production of small parts from sheet or strip material. | 8 |
FIELD OF THE INVENTION
This invention relates generally to radio antennas, and more particularly to improvements in a special form of antenna, known as a field probe. A field probe is used for measuring the strength of a radio frequency field. Field probes are particularly useful in the calibration of electromagnetic susceptibility testing equipment, in which an electronic device under test is exposed to a strong electromagnetic field swept through a range of frequencies. The invention relates specifically to improvements in E-field probes.
BACKGROUND OF THE INVENTION
An E-field probe for electromagnetic susceptibility testing generally comprises one or more short antennas mounted on a housing containing processing circuitry. To minimize distortion of the antenna pattern resulting from the presence of conductive feeder cables, the processing circuitry typically includes a transducer which converts a detected r.f. voltage to a modulated light beam, which is then conducted away from the probe through a fiber optic cable. A fiber optic cable may also be used to deliver D.C. operating power to the processing circuitry in the form of a laser beam.
An E-field probe is typically in the form of single axis probes or a three axis probe. In either case, it preferably utilizes one or more dipole antennas. Even though fiber optic light conductors are used to minimize distortion, for most probes, especially those operable over a range of frequencies including frequencies in the gigaHertz region, it is not practical to position the processing circuitry at the dipole center. Accordingly the conventional practice has been to connect a conductive feeder, i.e., a transmission line from the processing circuitry to the dipole center (or, in the case of a multi-axis probe, to the dipole centers). The feeder itself causes distortion of the antenna pattern. In conventional practice, the distortion caused by the transmission line is reduced by using a high resistance feeder.
Conventional E-field probes also tend be highly frequency dependent in practice, and require compensation in their associated electronic circuitry in order to be useful over a broad frequency range. In addition, conventional E-field probes, tend to exhibit asymmetry in their antenna patterns. Asymmetry exists with respect to an imaginary plane to which the dipole elements are perpendicular (orientation asymmetry) and with respect to arbitrarily selected imaginary planes in which the dipole elements lie (axial asymmetry).
Still another drawback of conventional E-field probes is their tendency to be affected by stray fields, including magnetic fields.
SUMMARY OF THE INVENTION
An important object of this invention, therefore, is to avoid one or more of the aforementioned drawbacks of conventional probes.
Briefly, the preferred E-field probe in accordance with the invention, comprises one or more dipoles, each comprising plural, parallel, strings of discrete resistors mounted on a section of printed circuit board and connected electrically so that the parallel strings are twisted about each other for optimum orientation symmetry and minimum stray field pick-up. The values of the individual resistors are chosen so that the dipole is essentially a tapered resistance dipole, providing good performance over a very broad range of frequencies.
A particularly desirable feature of the invention is the provision of a pair of diodes connected respectively in parallel strings of one arm of the dipole, but connected electrically to each other in the same direction, i.e., having a direct connection between the anode of one of the diodes and the cathode of the other diode. This arrangement of diodes allows the feeder to be constituted by a pair of parallel series of resistors of comparatively high resistance value continuing from the outer end of the arm in which the diodes are situated. In this way, the dipole is effectively “end fed” rather then center fed, and pattern distortion and axial asymmetry are minimized.
In accordance with one aspect of the invention, the field probe comprises at least one elongated element at least part of the length of which is composed of a plurality of closely coupled conductors, preferably two, disposed in substantially parallel, side-by-side relation to one another. As used herein, the term “closely coupled” with reference to parallel conductors means that the conductors are all situated within a cross-sectional area transverse to their direction of elongation, the largest dimension of which is much less than, i.e., not more than about one twentieth of, one wavelength at the highest frequency of intended operation. The highest frequency of intended operation is the maximum frequency where the antenna pattern (both in the E and H planes) has not significantly deviated from the pattern of an electrically short dipole. The term “parallel, side-by side relation,” when used with reference to conductors (including resistor strings) means that the conductors are not only parallel, but also that each end of one conductor is located adjacent an end of each other conductor.
In a practical electrically short probe, the conductors may be considered closely coupled when the maximum dimension of a transverse cross-section containing the conductors is within the range of approximately 0-15% of the length of the dipole portion of the probe. For a probe having a highest frequency of intended operation of 4.2 GHz, the largest dimension of the cross-sectional area in which the parallel conductors are located should be about 3.5 mm.
The elongated element is preferably a dipole antenna composed of two conductive elements, i.e., arms, extending in opposite directions from a dipole center at an intermediate location. At least one of the conductive elements is constituted by said part of the length of said at least one elongated element and comprises two closely coupled conductors disposed in substantially parallel, side-by-side relation to each other. These conductors extend from the intermediate location to an end location. Two terminals are provided at the end location, one terminal being at an end of one of the two closely coupled conductors and the other terminal being at an adjacent end of the other of the two closely coupled conductors. The probe includes processing circuitry and a transmission line having first and second opposite ends. The first end of the transmission line is connected to the processing circuitry, and the second end of the transmission line is connected directly to the dipole antenna at the terminals. The two closely coupled conductors are connected to each other at the intermediate location by a pair of diodes having a connection joining the diodes in series in the same direction electrically, and the other of the conductive elements is directly joined to said connection.
In a preferred embodiment, the conductors are resistive elements. Preferably, each resistance consists of plural discrete resistors connected in series. The discrete resistors preferably increase progressively in resistance with distance from the intermediate location on the dipole. In the case of two closely coupled resistances, the resistances are preferably twisted about each other.
If each of the closely coupled resistances is composed of two series of discrete resistors, the twisting of the resistances about each other is preferably achieved by situating alternate resistors of each series on opposite faces of a printed circuit board. The resistors on each side of the printed circuit board are disposed in a column parallel to the direction of elongation of said elongated dipole element, with the pairs of terminals of the resistors on each side of the printed circuit board situated in parallel lines in oblique relation to the direction of elongation of the elongated element. The resistors of each series may then be connected to one another by substantially straight conductors extending through the printed circuit board in perpendicular relation to the faces of the printed circuit board.
As will appear from the following detailed description, the invention provides an E-field probe having one or more of the following desirable characteristics: low antenna pattern distortion, a high degree of frequency independence, good symmetry, and stray field immunity.
Various other objects, details and advantages of the invention will be apparent from the following detailed description when read in conjunction with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram illustrating the mechanical configuration of a typical twisted, discrete resistor, tapered resistance element in accordance with the invention;
FIG. 2 is an electrical schematic of the same element;
FIG. 3 is a front elevational view showing the twisted, discrete resistor, tapered resistance element, including the printed circuit board on which the resistors of the element and associated processing circuitry are mounted;
FIG. 4 is a rear elevational view of the device of FIG. 3;
FIG. 5 is an elevational view of a single element probe incorporating a twisted, discrete resistor, tapered resistance element;
FIG. 6 is a perspective view of a three element probe incorporating three, mutually orthogonal twisted, discrete resistor, tapered resistance elements; and
FIG. 7 is a perspective view of an alternative version of the three element probe.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The mechanical configuration of a typical field probe element is shown in FIG. 1 . The field probe element comprises four sets, 10 , 12 , 14 and 16 of chip resistors. The chip resistors are mounted on a printed circuit board, which is not shown in FIG. 1 . Sets 10 and 14 are mounted on one side of the circuit board, while sets 12 and 16 are mounted on the opposite side of the circuit board.
The resistors are connected electrically by conductors shown as wires in FIG. 1 . Chip resistors “a” in sets 10 and 12 in the upper part of FIG. 1 are connected electrically in series by conductors 18 , 20 , etc. while chip resistors “b” in sets 10 and 12 are connected electrically series by conductors 22 , 24 , etc. The chips on one side of the board are tilted obliquely in one direction and the chips on the opposite side of the board are tilted obliquely in the opposite direction. The tilting of the chips enables the lowermost corner of each resistor to be located directly opposite the uppermost corner of the next resistor in each electrically connected series. With this opposed relationship between the corners of the resistors in the electrically connected series, the conductors can extend directly through the printed circuit board so that, in practice the conductors can be in the form of plated-through holes in the board.
It will be apparent from FIG. 1 that the two series of resistors “a” and “b” are twisted about each other, forming a resistive twisted pair.
Resistor sets 14 and 16 are similarly composed of a series of resistors “a” and a series of resistors “b” with electrical connections made through the circuit board in such a way that the series of resistors “a” and “b” are twisted about each other.
As seen in the middle portion of FIG. 1, resistor chip 26 , which is a “b” chip, is connected directly to resistor chip 28 , which is an “a” chip. by a conductor 30 , which is also connected to a common terminal of an integrated dual diode package 32 . The cathode of one of the diodes is connected through conductor 34 on the circuit board to and “a” resistor 36 , of set 14 and the anode of the other diode is connected through conductor 38 to a “b” resistor 40 of set 16 .
The electrical configuration of the resistors, and the diodes, are shown in FIG. 2 . In effect, the resistors above the interconnection 30 constitute one arm of a dipole, while some of the resistors below the diodes constitute the other arm of the dipole. Several resistors remote from the diodes, i.e., resistors 42 - 52 , serve as a twisted feeder, connecting the dipole antenna to a processing circuit 54 , which is preferably converts the received radio signal to an optical signal carried by a flexible fiber optic light conductor 56 . The fiber optic light conductor is not electrically conductive, and therefore has little influence on the antenna pattern of the probe.
The resistance values of the discrete resistors constituting the dipole preferably vary to cause the total antenna to approximate a tapered resistance dipole over its operating frequency range, the resistance increasing with distance from the center of the dipole at the location of the diodes. A tapered resistance dipole is described in Kanda, M. Standard Antennas for Electromagnetic Interference Measurements and Methods to Calibrate Them, IEEE Transactions on Electromagnetic Compatibility, Vol. 36, No. 4, November 1994. The Kanda paper is here incorporated by reference.
By way of example, typical values of resistors 26 , 28 , 36 and 40 are 68 Ω. The values of the six resistors in each series are typically 68 Ω, 82 Ω, 100 Ω, 150 Ω, 270 Ω and 560 Ω, respectively, progressing from the center of the dipole toward the tips. These values are for a probe designed to have a highest operating frequency between about 4 and 5 GHz. The dimensions of each dipole, and the values of the resistors, may be varied, depending on the intended upper frequency limit of the probe.
The tapered resistive loading, achieved by forming the dipole elements out of resistors having resistance values progressing from a low value to a higher value proceeding outward from the center of the dipole provides the probe with a broad band frequency response and suppresses the effect of the natural resonant frequency of the antenna. The use of closely coupled, plural strings of resistors to make up each element simulates the effect of a relatively thick dipole element, further improving the sensitivity of the probe.
The feeder resistors 42 - 52 should have much higher values, resistors 42 and 48 each typically having a resistance of 2 MΩ, and resistors 44 , 50 , 46 and 52 , each typically having a value of 390 KΩ.
Mounting of the resistors on opposite sides of a circuit board makes it possible to twist the resistor strings about each other as shown in FIG. 1 . The resistor strings forming the feeder are twisted about each other in the same manner as the resistor strings forming the dipole elements. Twisting of the resistor strings of the feeder reduces pick-up of extraneous fields, and twisting of the resistor strings forming the dipole elements improves the rotational symmetry of the dipole about its longitudinal axis. While it is important that the dipole element adjacent the feeder be composed of two or more strings of resistors, the dipole element remote from the feeder, of course, can be composed of a single string of resistors. However, both dipole elements are preferably formed of identical twisted resistor strings for symmetry.
Other variations on the number of resistor strings in each arm of the dipole are possible. For example, if four diodes are provided in series (connected electrically in the same direction) at the center of the dipole, the processing circuit can be connected through two parallel resistor strings of a first dipole arm to the outer ends of the series of diodes, a third resistor string, connected at one end to the connection of the second and third diodes, and with its other end free, can constitute a third string in the first dipole arm. The other dipole arm can comprise two parallel resistor strings connected respectively to the connection between the first and second diodes and the connection between the third and fourth diodes. Thus, in this variation, the dipole would have three resistor strings in one arm, and two resistor strings in its other arm.
An important feature of the preferred embodiment of the invention is the provision of the pair of diodes, 58 and 60 , at the center of the dipole. These diodes are connected electrically in the same direction in series with each other, and are located respectively in series with the resistor strings which form the dipole element adjacent the feeder. The diodes act together as a detector, providing a DC output to the processing circuit 54 , which varies in accordance with the magnitude of the E field to which the dipole is exposed.
In the case of a resistive dipole having a single diode at its center as a detector, with a two-conductor feed line carrying a DC signal away from the diode, a 180° reversal of the dipole will produce a different response to a given field unless the diode is operating in its square law region.
As shown in FIG. 2, the diodes of the preferred embodiment of the invention are effectively connected in series with each other, but are disposed in opposite directions in the resistive elements with which they are in series. As a result of the opposite directions of the two diodes, a symmetry is achieved which allows the detected responses to a given E-field to be identical when the dipole orientation is reversed, i.e., the dipole of FIGS. 1 and 2 is turned upside down through 180°, even if the diodes are operating outside their square law region.
The centrally located diode pair has the additional advantage that it allows the feeder to be connected to one of the outer ends of the dipole, thereby obviating a separate feeder connected to the center of the dipole, and eliminating adverse effects of a separate feeder on the axial symmetry of the dipole's antenna pattern. The centrally located diode pair also has a potential advantage in providing an increased response at low frequencies, which can be advantageous in some applications.
As mentioned previously, the mounting of the discrete resistors of the dipole and its feeder on a circuit board provides a convenient way to provide a dipole comprising twisted pairs of closely coupled resistive conductors. It also allows the processing circuitry and the dipole and feeder resistors to be mounted on a single circuit board, as shown in FIGS. 3 and 4. The circuit board can be formed with an elongated, narrow portion 62 extending outwardly from an edge of a broader portion 64 on which the various components of the processing circuit may be mounted, as shown in FIG. 3 . In a typical probe, the processing circuit will include amplification and compression circuitry and a converter to translate the DC response of the dipole to an optical signal for delivery through fiber optic light conductor 56 (FIG. 2) to an analog-to-digital converter (not shown) for translating the signal to a format in which it can be utilized in a computer.
The processing circuit can be powered in any of several ways. For example, it can carry its own battery power supply, or derive power from an on-board generating photocell energized by a beam transmitted through the light conductor toward the processing circuit from an external laser or other light source.
In the case of a single axis probe, the processing circuit can be contained within a housing 65 , as shown in FIG. 5 .
Plural probes can be incorporated into a unit to provide a probe comprising three mutually orthogonal dipoles for E-field measurements in three axes.
One such unit is depicted in FIG. 6, in which dipoles 66 , 68 and 70 extend respectively along x, y and z axes from a spherical housing 72 , which contains processing circuitry. Dipoles 66 and 68 can be formed on a single printed circuit board.
Another three-dimensional E-field probe, shown in FIG. 7, comprises three separate probes 74 , 76 and 78 , of the type shown in FIG. 5, disposed in mutually orthogonal relationship, crossing one another approximately at the dipole centers.
Various modifications can be made to the probes described. For example, the number of discrete resistors making up each dipole can vary, as can the number of discrete resistors making up the feeders. If the processing circuitry is small, the number of feeder resistors can be reduced, or the feeders can be eliminated altogether.
Advantage can be taken of certain features of the invention, for example the twisted, discrete resistor dipole arms, without connecting a feeder to the outer end of a dipole arm. For example, if the processing circuit is made small, it is possible and locate the processing circuit close to the dipole center rather than at an end of a dipole arm. Moreover, if a very small processing circuit is used, it can be provided on the circuit board at the location of the dipole center.
Still other modifications may be made to the apparatus and method described above without departing from the scope of the invention as defined in the following claims. | An E-field probe comprises one or more dipoles, each comprising plural, parallel, strings of discrete resistors mounted on a section of printed circuit board and connected electrically so that the parallel strings are twisted about each other for optimum orientation symmetry and minimum stray field pick-up. The values of the individual resistors are chosen so that the dipole is essentially a tapered resistance dipole, providing good performance over a very broad range of frequencies. A pair of diodes connected respectively in parallel strings of one arm of the dipole allows the feeder to be constituted by a pair of parallel series of resistors of comparatively high resistance value continuing from the outer end of the arm in which the diodes are situated. The dipole is effectively “end fed” rather then center fed, and pattern distortion and axial asymmetry are minimized. | 7 |
CONTINUING DATA
This application claims priority from co-pending U.S. Ser. No. 14/181,573, filed Feb. 14, 2014, entitled “Minimally Invasive Intervertebral Staple Distraction Devices”, Frasier et al., which is a divisional application from U.S. Ser. No. 13/784,122, filed Mar. 4, 2013, entitled “Minimally Invasive Intervertebral Staple Distraction Devices”, Frasier et al., and from U.S. patent application Ser. No. 12/558,092, filed Sep. 11, 2009, entitled “Minimally Invasive Intervertebral Staple Distraction Devices”, Frasier et al., (now U.S. Pat. No. 8,403,988), the specifications of which are hereby incorporated by reference in their entireties.
BACKGROUND OF THE INVENTION
The natural intervertebral disc contains a jelly-like nucleus pulposus surrounded by a fibrous annulus fibrosus. Under an axial load, the nucleus pulposus compresses and radially transfers that load to the annulus fibrosus. The laminated nature of the annulus fibrosus provides it with a high tensile strength and so allows it to expand radially in response to this transferred load.
In a healthy intervertebral disc, cells within the nucleus pulposus produce an extracellular matrix (ECM) containing a high percentage of proteoglycans. These proteoglycans contain sulfated functional groups that retain water, thereby providing the nucleus pulposus within its cushioning qualities. These nucleus pulposus cells may also secrete small amounts of cytokines such as interleukin-1β and TNF-α as well as matrix metalloproteinases (“MMPs”). These cytokines and MMPs help regulate the metabolism of the nucleus pulposus cells.
In some instances of disc degeneration disease (DDD), gradual degeneration of the intervetebral disc is caused by mechanical instabilities in other portions of the spine. In these instances, increased loads and pressures on the nucleus pulposus cause the cells within the disc (or invading macrophases) to emit larger than normal amounts of the above-mentioned cytokines. In other instances of DDD, genetic factors or apoptosis can also cause the cells within the nucleus pulposus to emit toxic amounts of these cytokines and MMPs. In some instances, the pumping action of the disc may malfunction (due to, for example, a decrease in the proteoglycan concentration within the nucleus pulposus), thereby retarding the flow of nutrients into the disc as well as the flow of waste products out of the disc. This reduced capacity to eliminate waste may result in the accumulation of high levels of toxins that may cause nerve irritation and pain.
As DDD progresses, toxic levels of the cytokines and MMPs present in the nucleus pulposus begin to degrade the extracellular matrix, in particular, the MMPs (as mediated by the cytokines) begin cleaving the water-retaining portions of the proteoglycans, thereby reducing its water-retaining capabilities. This degradation leads to a less flexible nucleus pulposus, and so changes the loading pattern within the disc, thereby possibly causing delamination of the annulus fibrosus. These changes cause more mechanical instability, thereby causing the cells to emit even more cytokines, thereby upregulating MMPs. As this destructive cascade continues and DDD further progresses, the disc begins to bulge (“a herniated disc”), and then ultimately ruptures, causing the nucleus pulposus to contact the spinal cord and produce pain.
One proposed method of managing these problems is to remove the problematic disc and replace it with a porous device that restores disc height and allows for bone growth therethrough for the fusion of the adjacent vertebrae. These devices are commonly called “fusion devices”, or “interbody fusion devices”.
Current spinal fusion procedures such as transforaminal lumbar interbody fusion (TLIF), posterior lumbar interbody fusion (PLIF), and extreme lateral interbody fusion (XLIF) procedures typically require an 18 mm minimum diameter tube to place an interbody fusion device. Reducing the size of this access portal would help to reduce incision size and muscle trauma due to the procedure. An interbody device that can be inserted through a port that is smaller than the device's final size would help to achieve the goal of reducing incision size, while maintaining proper disc height restoration and providing adequate anterior column support.
US Patent Publication No. 2004-0073213 (“Serhan”) is directed toward a device for distracting vertebrae and subsequently delivering a flowable material into the disc space. The distal portion of the device is adapted to distract the vertebrae and the device includes a port for distal delivery of a flowable material.
US Patent Publication No. 2001-0032020 (“Besselink”) discloses an expandable intervertebral cage that can accommodate a reinforcing element that itself expands to substantially fill the hollow central portion of the cage.
US Patent Publication No. 2003-0208203 (“Lim”) describes a purportedly minimally invasive, articulating insertion instrument for implants, wherein the articulating feature is used to minimize the implant's footprint such that the implant's footprint is transverse to the longitudinal axis of the instrument.
US Patent Publication No. 2004-0230309 (“DePuy Spine”) relates to an orthopaedic device for implantation between adjacent vertebrae, the device comprising an arcuate balloon and a hardenable material within the balloon. In some embodiments, the balloon has a footprint that substantially corresponds to a perimeter of a vertebral endplate. An inflatable device is inserted through a cannula into an intervertebral space and oriented so that, upon expansion, a natural angle between vertebrae will at least be partially restored. At least one material component selected from the group consisting of a load-bearing component and an osteobiologic component is directed into the inflatable device through fluid communication means.
US Patent Publication No. 2007-0149978 (“Shezifi”) relates to a device for distracting and supporting two substantially opposing tissue surfaces in a minimally invasive procedure. The device comprises a wrapping element and expandable structure insertable between the two substantially opposing support surfaces of the wrapping element and adapted to be expanded between the two substantially opposing surfaces to a predetermined dimension.
US Patent Publication No. 2007-0233254 (“Grotz”) is related to expanding spine cages that purportedly expand to conformably engage the endplates of vertebrae by hydraulic means.
Thus, there is a need for additional minimally invasive intervertebral distraction devices and techniques such as those hereinafter disclosed.
SUMMARY OF THE INVENTION
The present invention is directed to achieving intervertebral disc repair through the minimally invasive insertion of a plurality of staple-like implants into the disc space and their subsequent rotation.
This invention concerns minimally invasive implants and devices for use in the intervertebral disc space, and particularly those capable of restoring intervertebral disc height though a percutaneous access portal having a diameter of approximately 10 mm or less.
This invention preferably concerns minimally invasive, staple-like implants and instruments for use in the intervertebral disc space, and especially those capable of restoring intervertebral disc height upon head-over-tail rotation, wherein the implants are inserted into a disc space though an access portal having a diameter no more than 10 mm, and preferably no more than 5 mm.
In preferred embodiments thereof, a plurality of small, staple-like supports are inserted lengthwise through a small tube into the disc space and then rotated into position upon the anterior edges of opposing vertebral body endplates. The tooth-like geometries on the proximal and distal faces of these staples mate with the outer anterior edges of the vertebral body. Preferably, staple placement should be on or near the load bearing portion of the vertebral body (e.g., on the anterior, lateral, or posterior cortical rim or any combination of placements). The proximal and distal faces of the staples have teeth that dig into the endplate on the inside of the vertebral rim as well.
Preferably, multiple staples are placed around the anterior portion of the vertebral body, and then are linked together with wires, cables, or other attachments to form the desired support structure. The wires are tensioned inward towards the center of the disc space while the staple protruding beyond the anterior edge of the endplate keeps the staple in place.
DESCRIPTION OF THE DRAWINGS
FIG. 1 discloses a perspective view of a preferred intervertebral distraction device of the present invention.
FIG. 2 discloses the device of FIG. 1 implanted in an intervertebral region (shown without discectomy).
FIGS. 3 a -3 m disclose the sequential steps of a preferred method of implanting the intervertebral distraction device of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
A preferred embodiment of this invention relates to an intervertebral distraction device such as that depicted in FIG. 1 .
FIG. 2 discloses the device of FIG. 1 implanted in an intervertebral region (shown without discectomy).
Referring now to FIGS. 1-2 , intervertebral distraction device 1 comprises an intervertebral fusion cage comprising:
a) an anterior wall 3 having a width W and a height H, b) first and second side walls 5 extending posteriorly from the anterior wall, each side wall having a length L,
wherein an upper end portion 6 of the anterior wall and each side wall collectively form an upper bearing surface 7 adapted for gripping an upper vertebral endplate, the upper bearing surface defining at least one upper opening 9 therethrough adapted to promote bony fusion,
wherein a lower end portion 10 of the anterior wall and each side wall collectively form a lower bearing surface 11 adapted for gripping a lower vertebral endplate, the lower bearing surfaces defining at least one lower opening 13 therethrough adapted to promote bony fusion,
wherein the height H of the anterior wall is greater than the width W of the anterior wall, and
wherein the height H of the anterior wall is greater than the length L of each side wall.
In some embodiments, the height of the anterior wall is at least two times greater than the width of the anterior wall. More preferably, the height of the anterior wall is at least three times greater than the width of the anterior wall.
In some embodiments, the height of the anterior wall is at least two times greater than the length of each side wall. More preferably, the height of the anterior wall is at least three times greater than the length of each side wall.
Preferably, the height of the anterior wall is at least two times greater than the width of the anterior wall and is at least two times greater than the length of each side wall.
More preferably, the height of the anterior wall is at least three times greater than the width of the anterior wall and is at least three times greater than the length of each side wall.
The thickness of the staple depends on the method of deployment. In some embodiments, the staple could resemble a thick strut where the thickness approximates the height. In other embodiments, the thickness could approximate the width. A thick staple would act like a ramp cage with anterior lip staple tines. A thin staple would act like a column support on the cortical rim. The ramp staple could have at least one through-hole to enable fusion through the implant. If no through-hole is present, the interbody fusion mass is expected to take place proximal to but around the staple.
FIGS. 3 a -3 m disclose the sequential steps in a preferred method of implanting an intervertebral distraction device of the present invention into an intervertebral disc space.
Now referring to FIG. 3 a , there is provided an instrument for inserting the device of the present invention. The instrument comprises a fork having a pair of tynes 103 , wherein each tyne has a boss 105 extending from its inner surface 106 . Also provided in FIG. 3 a is a staple 107 having a) an anterior wall 108 having a center hole 110 , and b) a pair of side walls 109 extending from the anterior wall. In each side wall, there is a pocket 111 for pivotally accepting the respective boss. This pocket may be provided in the form of either a blind recess or a throughhole.
Now referring to FIG. 3 b , the fork is attached to staple 100 by snapping the spring-loaded tynes 103 of the fork over (or inside) the side walls of the staple body so that the bosses of the fork locate in the pockets of the staple. Because the boss-pocket couple is adapted for pivotal movement, rotation of the staple about the boss axis (which is defined by the two bosses) may be easily accomplished. In some embodiments, the coupling can pivot in place and lock.
Now referring to FIG. 3 c , to prepare the device for insertion, one end ( 113 in FIG. 3 g ) of wire 115 is attached to the staple through the center hole in the staple's anterior wall. The wire is then manipulated to rotate the staple about the boss axis so that the staple's anterior wall 108 lies approximately parallel to the tynes of the fork. This low profile orientation allows the assembly to pass through a narrow-opening delivery portal.
Now referring to FIG. 3 d , a port 121 having an axial delivery bore 123 is inserted into the spine in a manner that accesses a predetermined intervertebral disc. Once this access portal is in place, the surgeon may choose to remove disc material through the bore, using any number of conventional disc removal tools. Preferably, at least the nucleus pulposus portion of the disc material is substantially removed.
Now referring to FIG. 3 e , an assembly 125 comprising the staple, the fork and the wire is inserted through port 121 into the cleared disc space, thereby accomplishing a minimally invasive insertion of the staple.
Now referring to FIG. 3 f , after the staple 107 is positioned near an anterior edge of the vertebral body using either fluoroscopy or a camera-based vision system, the wire 115 and fork 101 are manipulated to rotate the staple 107 into place. Rotation can be in either the coronal or saggital plane, or in the transverse plane followed by coronal or saggital rotation. In this vertical orientation, the teeth of the staple bite into the opposing edges of the upper and lower vertebral bodies, thereby stabilizing the staple in the disc space.
Now referring to FIG. 3 g , the fork is then removed, leaving staple 107 in place with its wire still connected thereto, and with the port still in place as well.
Now referring to FIG. 3 h , a second port 221 is now placed into the same disc space, but from a position on an opposite lateral side of the spinal cord.
Now referring to FIGS. 3 i and 3 j , a second staple 200 and wire 215 are inserted through port 221 into the disc space using the fork 101 . The second staple is likewise rotated into place at a second intradiscal location in the same manner as the first staple. In FIG. 3 j , the upper vertebra has been removed for clarity.
Now referring to FIGS. 3 k and 3 l , the fork is then removed from the second port. Then, wires 115 and 215 are tensioned and attached together within the disc space, using a crimp or other equivalent method. In FIG. 3 l , the upper vertebra has again been removed for clarity. The crimp creates tension in the wires to hold the wires in place. Now referring to FIG. 3 m , the access portals are then removed, leaving both the staples 107 , 200 and wires 115 , 215 in place. The tension on the wires keeps the staples from moving anteriorly, and the teeth on the staples keep the staples from moving posteriorly. The remaining disc space can then be filled with any desired bone growth agent (such as allograft bone) in order to promote fusion. If desired, more than two staples can be used to form the support structure, and this may be accomplished by changing the trajectory of the ports to place additional staples around the rim of the vertebral body.
Therefore, in accordance with the present invention, there is provided an assembly comprising;
a) an intervertebral fusion device comprising;
i) a anterior wall having a width and a height,
ii) first and second side walls extending posteriorly from the anterior wall, each side wall having a length,
wherein an upper end portion of the anterior wall and each side wall form an upper bearing surface adapted for gripping an upper vertebral endplate, the upper bearing surface defining at least one upper opening therethrough adapted to promote bony fusion,
wherein a lower end portion of the anterior wall and each side wall form a lower bearing surface adapted for gripping a lower vertebral endplate, the lower bearing surfaces defining at least one lower opening therethrough adapted to promote bony fusion,
b) a fork comprising a pair of tynes, each tyne having an inner surface and a boss extending from its inner surface,
wherein each boss is pivotally received in its respective pocket.
Also in accordance with the present invention, there is provided a method of inserting a fusion cage comprising
i) an anterior wall having a width and a height, ii) first and second side walls extending posteriorly from the anterior wall, each side wall having a length, wherein an upper end portion of the anterior wall and each side wall form an upper bearing surface adapted for gripping an upper vertebral endplate, the upper bearing surface defining at least one upper opening therethrough adapted to promote bony fusion, wherein a lower end portion of the anterior wall and each side wall form a lower bearing surface adapted for gripping a lower vertebral endplate, the lower bearing surfaces defining at least one lower opening therethrough adapted to promote bony fusion,
the method comprising the steps of:
a) inserting the fusion cage into the disc space in an orientation whereby the anterior wall faces a vertebral endplate, and a first bearing surface precedes a second bearing surface, and b) pivoting the fusion cage so that the upper bearing surfaces bear upon the upper vertebral endplate and the lower bearing surfaces bear upon the lower vertebral endplate.
In some embodiments (not shown), the staple further has a posterior wall that connects the two side walls and extends from the upper bearing surface to the lower bearing surface. In some embodiments thereof, the region between the anterior and posterior wall is open to form an annulus that allows for fusion therethrough.
In some embodiments wherein the staple further has a posterior wall, the region between the anterior and posterior wall is closed to form a rod.
In some embodiments in which the staple further has a posterior wall, the axial cross section of the staple is substantially circular.
Preferably, these fusion devices of the present invention may be made from any non-resorbable structural material appropriate for human surgical implantation, including but not limited to, surgically appropriate metals, and non-metallic materials, such as carbon fiber composites, polymers and ceramics. However, resorbable staples are also contemplated by the present invention.
The interbody device may be preferably made out of PEEK or CFRP, or any other suitable material providing adequate strength and radiolucency. However, implantable metals such as titanium or stainless steel components may be required to ensure adequate strength for the interbody device. In some cases, the interbody device can be made as a combination of PEEK and metal. In some cases, resorbable materials such as polylactide, polyglycolide, and magnesium are preferred.
In some embodiments, the cage material is selected from the group consisting of PEEK, ceramic materials and metallic materials. The cage material is preferably selected from the group consisting of a metal material and a composite (such as PEEK/carbon fiber).
If a metal is chosen as the material of construction for the staple, then the metal is preferably selected from the group consisting of titanium, titanium alloys (such as Ti-6Al-4V), chrome alloys (such as CrCo or Cr—Co—Mo) and stainless steel.
If a polymer is chosen as a material of construction for the staple, then the polymer is preferably selected from the group consisting of polyesters, (particularly aromatic esters such as polyalkylene terephthalates), polyamides; polyalkenes; poly(vinyl fluoride); PTFE; polyarylethyl ketone PAEK; polyphenylene and mixtures thereof.
If a ceramic is chosen as the material of construction for the staple, then the ceramic is preferably selected from the group consisting of alumina, zirconia and mixtures thereof. It is preferred to select an alumina-zirconia ceramic, such as BIOLOX Delta™, available from CeramTec of Plochingen, Germany. Depending on the material chosen, a smooth surface coating may be provided thereon to improve performance and reduce particulate wear debris.
In some embodiments, the staple comprises PEEK. In others, it is a ceramic.
In some embodiments, the staple consists essentially of a metallic material, preferably a titanium alloy or a chrome-cobalt alloy.
In some embodiments, the staple is made of a stainless steel alloy, preferably BioDur® CCM Plus® Alloy available from Carpenter Specialty Alloys, Carpenter Technology Corporation of Wyomissing, Pa. In some embodiments, the outer surfaces of the staple are coated with a sintered beadcoating, preferably Porocoat™, available from DePuy Orthopaedics of Warsaw, Ind.
In some embodiments, the staples are made from a composite comprising carbon fiber. Composites comprising carbon fiber are advantageous in that they typically have a strength and stiffness that is superior to neat polymer materials such as a polyarylethyl ketone PAEK. In some embodiments, each staple is made from a polymer composite such as a PEKK-carbon fiber composite.
Preferably, the composite comprising carbon fiber further comprises a polymer. Preferably, the polymer is a polyarylethyl ketone (PAEK). More preferably, the PAEK is selected from the group consisting of polyetherether ketone (PEEK), polyether ketone ketone (PEKK) and polyether ketone (PEK). In preferred embodiments, the PAEK is PEEK.
In some embodiments, the carbon fiber comprises between 1 vol % and 60 vol % (more preferably, between 10 vol % and 50 vol %) of the composite. In some embodiments, the polymer and carbon fibers are homogeneously mixed. In others, the material is a laminate. In some embodiments, the carbon fiber is present in a chopped state. Preferably, the chopped carbon fibers have a median length of between 1 mm and 12 mm, more preferably between 4.5 mm and 7.5 mm. In some embodiments, the carbon fiber is present as continuous strands.
In especially preferred embodiments, the composite comprises:
a) 40-99% (more preferably, 60-80 vol %) polyarylethyl ketone (PAEK), and
b) 1-60% (more preferably, 20-40 vol %) carbon fiber,
wherein the polyarylethyl ketone (PAEK) is selected from the group consisting of polyetherether ketone (PEEK), polyether ketone ketone (PEKK) and polyether ketone (PEK).
In some embodiments, the composite consists essentially of PAEK and carbon fiber. More preferably, the composite comprises 60-80 wt % PAEK and 20-40 wt % carbon fiber. Still more preferably, the composite comprises 65-75 wt % PAEK and 25-35 wt % carbon fiber.
Although the present invention has been described with reference to its preferred embodiments, those skillful in the art will recognize changes that may be made in form and structure which do not depart from the spirit of the invention.
In other embodiments, the components are made from resorbable materials, such as Biocryl Rapide™, a PLA, PLG, TCP composite marketed by DePuy Mitek, located in Raynham, Mass.
When resorbable materials are selected, Preferred bioresorbable materials which can be used to make the staples of the present invention include bioresorbable polymers or copolymers, preferably selected from the group consisting of hydroxy acids, (particularly lactic acids and glycolic acids; caprolactone; hydroxybutyrate; dioxanone; orthoesters; orthocarbonates; and aminocarbonates). Preferred bioresorbable materials also include natural materials such as chitosan, collagen, cellulose, fibrin, hyaluronic acid; fibronectin, and mixtures thereof. However, synthetic bioresorbable materials are preferred because they can be manufactured under process specifications which insure repeatable properties.
A variety of bioabsorbable polymers can be used to make the suture of the present invention. Examples of suitable biocompatible, bioabsorbable polymers include but are not limited to polymers selected from the group consisting of aliphatic polyesters, poly(amino acids), copoly(ether-esters), polyalkylenes oxalates, polyamides, tyrosine derived polycarbonates, poly(iminocarbonates), polyorthoesters, polyoxaesters, polyamidoesters, polyoxaesters containing amine groups, poly(anhydrides), polyphosphazenes, biomolecules (i.e., biopolymers such as collagen, elastin, bioabsorbable starches, etc.) and blends thereof. For the purpose of this invention aliphatic polyesters include, but are not limited to, homopolymers and copolymers of lactide (which includes lactic acid, D-,L- and meso lactide), glycolide (including glycolic acid), ε-caprolactone, p-dioxanone (1,4-dioxan-2-one), trimethylene carbonate (1,3-dioxan-2-one), alkyl derivatives of trimethylene carbonate, δ-valerolactone, β-butyrolactone, χ-butyrolactone, ε-decalactone, hydroxybutyrate, hydroxyvalerate, 1,4-dioxepan-2-one (including its dimer 1,5,8,12-tetraoxacyclotetradecane-7,14-dione), 1,5-dioxepan-2-one, 6,6-dimethyl-1,4-dioxan-2-one, 2,5-diketomorpholine, pivalolactone, χ,χ-diethylpropiolactone, ethylene carbonate, ethylene oxalate, 3-methyl-1,4-dioxane-2,5-dione, 3,3-diethyl-1,4-dioxan-2,5-dione, 6,8-dioxabicycloctane-7-one and polymer blends thereof. Poly(iminocarbonates), for the purpose of this invention, are understood to include those polymers as described by Kemnitzer and Kohn, in the Handbook of Biodegradable Polymers , edited by Domb, et. al., Hardwood Academic Press, pp. 251-272 (1997). Copoly(ether-esters), for the purpose of this invention, are understood to include those copolyester-ethers as described in the Journal of Biomaterials Research, Vol. 22, pages 993-1009, 1988 by Cohn and Younes, and in Polymer Preprints (ACS Division of Polymer Chemistry), Vol. 30(1), page 498, 1989 by Cohn (e.g. PEO/PLA). Polyalkylene oxalates, for the purpose of this invention, include those described in U.S. Pat. Nos. 4,208,511; 4,141,087; 4,130,639; 4,140,678; 4,105,034; and 4,205,399. Polyphosphazenes, co-, ter- and higher order mixed monomer-based polymers made from L-lactide, D,L-lactide, lactic acid, glycolide, glycolic acid, para-dioxanone, trimethylene carbonate and ε-caprolactone such as are described by Allcock in The Encyclopedia of Polymer Science , Vol. 13, pages 31-41, Wiley Intersciences, John Wiley & Sons, 1988 and by Vandorpe, et al in the Handbook of Biodegradable Polymers , edited by Domb, et al, Hardwood Academic Press, pp. 161-182 (1997). Polyanhydrides include those derived from diacids of the form HOOC—C 6 H 4 —O—(CH 2 ) m —O—C 6 H 4 —COOH, where m is an integer in the range of from 2 to 8, and copolymers thereof with aliphatic alpha-omega diacids of up to 12 carbons. Polyoxaesters, polyoxaamides and polyoxaesters containing amines and/or amido groups are described in one or more of the following U.S. Pat. Nos. 5,464,929; 5,595,751; 5,597,579; 5,607,687; 5,618,552; 5,620,698; 5,645,850; 5,648,088; 5,698,213; 5,700,583; and 5,859,150. Polyorthoesters such as those described by Heller in Handbook of Biodegradable Polymers , edited by Domb, et al, Hardwood Academic Press, pp. 99-118 (1997).
It should be understood that the foregoing disclosure and description of the present invention are illustrative and explanatory thereof and various changes in the size, shape and materials as well as in the description of the preferred embodiment may be made without departing from the spirit of the invention. | Multiple, small, staple-like supports are inserted through a small tube into the disc space then rotated into position on the edge of the vertebral bodies. The tooth-like geometry of the proximal and distal faces of these staples mates with the outer edge of the vertebral body, extending past the front of the endplate anteriorly. The staples have teeth that dig into the endplate on the inside of the rim as well. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is directed to a dental x-ray diagnostics installation for producing panorama tomograms of the jaw of a patient, and in particular to such an installation wherein the radiation intensity is measured by clocked CCD sensors which are operated at a clock frequency to simulate a moving x-ray film.
2. Related Patent and Application
A dental x-ray diagnostics installation for producing panorama tomograms of the jaw of a patient, wherein the moving x-ray film used in previous installations of this type is replaced by a clocked CCD sensor arrangement operated to simulate the moving film, is disclosed in U.S. Pat. No. 4,823,369. The details of operation of the CCD sensor are disclosed in U.S. Pat. No. 4,878,234, and which is assigned to the same assignee as the present application.
The dental x-ray installation disclosed in the above differs from conventional panorama tomogram exposure equipment in that the x-ray film, which is moved behind the secondary diaphragm in conventional systems, is replaced by a stationary CCD sensor arrangement which is driven with a clock generator so that the charge images which are obtained are entered into a storage zone at a clock frequency to simulate the same speed at which the conventional x-ray film is moved relative to the secondary diaphragm. The charge images are then clocked out line-by-line by a shift register. The clock frequency f T is selected according to the relationship:
f.sub.T =v/(n.sub.x ·a)
wherein v is the conventional film speed, n x is the imaging relationship of the image-transmitting system, and a is the line spacing.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide, in a clocked CCD sensor dental x-ray panorama tomographic installation, the capability of simultaneously acquiring a plurality of tomograms during one exposure, with the tomograms being selectable within certain limits.
It is a further object of the present invention to provide such an installation wherein accurate tomograms of slices which lie on a curved path, rather than in one plane, can be obtained, for example, tomograms of teeth disposed at an angle in the jaw.
These and other objects ar achieved in accordance with the principles of the present invention in an x-ray diagnostics installation having a clocked CCD sensor arrangement for recording the x-radiation intensity has at least some of the CCD columns driven at different clock frequencies via separate clock inputs, thereby permitting a plurality of slices to be simultaneously acquired during the execution of a single exposure. Moreover, each slice can be freely defined within certain limits.
The different clock drives need not be used to clock the entire CCD sensor (or the entire CCD sensor arrangement, if more than one CCD sensor is used); the differing clock drive can be used to drive only specific regions of the CCD sensor, or only selected ones of the sensors comprising a CCD sensor arrangement. The clock frequencies used to drive different groups of columns can be divided such that the slice being recorded assumes a curved path, so that teeth lying at an angle within the jaw can be sharply imaged.
The depth of field of the acquired image can be varied by varying the width of the image zone within the CCD sensor by rendering some of the lines of the sensor passive.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an x-ray diagnostics installation wherein moving x-ray film is replaced by a CCD sensor.
FIG. 2 is a perspective view of a detector and sensor arrangement using a single CCD sensor.
FIG. 3 is a perspective view of a detector and sensor arrangement using more than one CCD sensor.
FIG. 4 is a schematic block diagram of signal processing components for the dental installation shown in FIG. 1.
FIG. 5 is a front view of the opening of the secondary diaphragm in the installation of FIG. 1 showing a segment to explain the operation of the apparatus.
FIG. 6 is a plane view of a CCD sensor used in the installation of FIG. 1 segmented to explain the operation of the apparatus.
FIG. 7 is a schematic illustration for explaining the drive of columns in a CCD sensor as shown in FIGS. 5 and 6 using differing clock frequencies in accordance with the principles of the present invention.
FIGS. 8, 9 and 10 are schematic illustrations showing charge transfer in a CCD sensor with columns driven at different clock frequencies in accordance with the principles of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The x-ray diagnostics installation shown in FIGS. 1-4 is as disclosed in the aforementioned U.S. Pat. No. 4,283,369 and the CCD sensor structure and operation shown in FIGS. 5 and 6 are as disclosed in the aforementioned U.S. Pat. No. 4,878,234 with some details having been added to FIG. 6 to explain the principles of the present invention. The installation includes a rotary unit generally referenced 1, consisting of an x-ray source 3 and a secondary diaphragm 7, with a detector arrangement 4 attached thereto, mounted at opposite ends of a carrier 2. The rotary unit 1 can be rotated around the head of a patient 5 in a known manner, as indicated by the arrow. Adjustment and control devices for rotating the unit 1 to generate a panorama tomogram of the jaw of the patient 5 are known to those skilled in the art, and need not be further described. It need only be noted that the head of the patient 5 is fixed in position with a mount (not shown) during an exposure, and the rotary unit 1 moves with a defined speed around the patient 5 given a prescribed exposure time. This movement is undertaken such that the x-ray emitted by the x-ray source incident on the jaw of the patient 5 at substantially a right angle, and a substantially constant distance between the jaw and the detector 4 is maintained.
The secondary diaphragm 7 has a slot-like opening 8 having dimensions of, for example, 5×125 mm. The opening 8 is followed by means for converting the x-rays into visible light radiation. In the exemplary embodiment, a scintillator layer 9 having substantially the same dimensions as the opening 8 is provided for this purpose in the plane of the opening 8. The scintillator layer 9 is followed by an image transmission or coupling element 10, such as fiber optics, which reduces the format of the secondary diaphragm opening 8 to the format of the image zone of a CCD sensor 11. The image zone of the CCD sensor 11 has dimensions of, for example, 8×8 mm.
The CCD sensor 11 is of the type having an image zone 11a and a storage zone 11b disposes spatially separated on a chip, and having a shift register 11c coupled to the storage zone 11b. It is also possible, however, to use a CCD sensor of the type wherein the image and storage zones are disposed together within a chip.
To simplify the following description, it shall be assumed that the entire extent of the opening 8 in the secondary diaphragm 11 is imaged onto the surface of a single CCD sensor, as shown in FIG. 2. It is possible, however, to provide a plurality of such CCD sensors to cover the entirety of the opening 8, as shown in the embodiment of FIG. 3. In the embodiment of FIG. 3, two CCD sensors 12 and 13 are disposed at substantially a right angle relative to the plane of the opening 8, and two fiber optic elements 14 and 15 are provided as the transmission or coupling elements. The individual CCD sensors are of the same type as shown in FIG. 2, that is, with a storage zone spatially separated from an image zone, with a following shift register.
Processing of the electronic signals from the sensor 11 is undertaken using the components shown in Figure 4. The output of the shift register 11c is supplied to an analog-to-digital converter 16, which is followed by a digital image processing system including a pre-processing unit 17, an image memory 18, an image read-out unit 19, a display 20, a computer 21 and a clocks pulse generator 22. Image data in the form of voltage signals generated by charge proportional to the x-ray intensity are supplied at the output of the shift register 11c. These voltages are converted to digital signals in the converter 16. These digital values can then either be directly entered and stored in the image memory 18, or can be entered and stored in the image memory 18 after pre-processing in the unit 17. The computer 21 provides control (read-out) instructions required for this purpose through the clock pulse generator 22.
Direct entry of signals from the analog-to-digital converter 16 into the image memory 18 is preferable if the image memory 18 has a sufficiently large memory capacity, which can be justified given the constraints of cost and physical size. If direct entry is undertaken, the data are stored only during rotation of the rotary unit 1 which is necessary to complete an exposure, and after the conclusion of this exposure the data are processed, i.e., are added to generate a tomogram of the desired slice of the patient's jaw. Even though a relatively large amount of data must be processed for this purpose, this method has the advantage that a subsequent visual representation of a plurality of different slices is possible.
If, however, it is not economically justifiable to provide an image memory 18 having such a large memory capacity, the pre-processing unit 17 may be interposed between the converter 16 and the image memory 18, as indicated with dashed lines in FIG. 4. The pre-processing unit 17 includes an intermediate memory and a signal processor, by means of which the digital data from the converter 16 are added as a function of time based on a control instruction from the computer 21. This addition is undertaken to generate a tomogram of a desired slice of the patient's jaw. The processed data are subsequently forwarded to the image memory 18. An image memory 18 having a lower memory capacity can thus be used if the pre-processing unit 17 is present. If the preprocessing unit 17 is used, however, the slice or tomograph position (i.e., depth) is fixed, so that the slice position can not be varied within certain limits, as would be possible without the pre-processing unit 17, wherein the image data are not combined to form a tomogram until after a complete exposure.
A compromise solution is possible, however, wherein a plurality of adjacent image columns (i.e., data sets corresponding to successive positions of the secondary diaphragm 7, and thus of the opening 8 therein) are added as a function of time before storing this data, and the subsequent addition of these sum columns to form an image column is not undertaken until after storing the data. Using this method, the pre-processing unit 17 is not required to add all of the data, but only the data for a few adjacent columns. The data for these few columns are added as a function of time under the control of the computer 21, and are then forwarded to the image memory 18
The creation of an image in the above-described apparatus shall be discussed below with reference to FIGS. 5 and 6.
The patient 5 is transradiated by a rectangular slot-shaped x-ray beam defined by a primary diaphragm (not shown) situated in the x-ray source 3. The radiation passes through the opening 8 of the secondary diaphragm 7 and is incident on the scintillator layer 9, wherein the x-radiation is converted into light radiation, to be registered by the CCD sensor 11. The signals registered by the CCD sensor 11 are proportional to the radiation intensity of the x-radiation attenuated by the patient 5.
In conventional tomographic techniques, an x-ray film to be exposed is moved at a defined speed behind the opening 8 of the secondary diaphragm 7, with the speed of film movement being a factor which defines the position (depth) of the tomographic slice. The position of the tomographic slice can thus be modified by varying the film speed. As described below, in the apparatus disclosed herein the x-ray film is replaced by an electronic detector arrangement, and the signals generated by the electronic detector arrangement are processed in a manner to generate a panorama tomogram corresponding to a tomogram produced using conventional moving film technology, but which can be reproduced on a television monitor.
The relationship between the opening 8 and the image zone 11a of the CCD sensor 11 shall first be described with reference to FIGS. 5 and 6. It is assumed that the opening 8 is imaged on the image zone of one or more such CCD sensors. The imaging relationship in the x-direction, i.e., perpendicular to the longitudinal extent of the opening 8, is defined by the ratio 1:n x , and by the ratio 1:n y in the y-direction. Because the opening 8 has a width of about 5 mm, and currently available CCD sensors have an image zone width of about 5 mm, and currently available CCD sensors have an image zone width of 8 mm, n x =1 is applicable in the present context. Dependent on the number and size of image sensors employed, the imaging scale n y is the longitudinal (y) slot direction can be between 1 and about 20.
A picture element (pixel) on the CCD image zone surface having the dimensions a×b (a=row or line spacing, b=column spacing) corresponds to a pixel of (n x a) x (n y in the plane of the opening 8. In the simplified overview of FIGS. 5 and 6, 1 through n correspond to charge pixels in the CCD sensor, and also identify pixels in the direction of the longitudinal extent of the secondary opening 8. Accordingly, a line in this longitudinal direction of the secondary opening 8 is imaged on a CCD row or line.
By the application of clock pulses from the clock pulse generator 22, a charge image is transferred from the image zone 11a into the storage zone 11b, and is then read-out from the storage zone 11b via the shift register 11c, for supply to the analog-to-digital converter 16. During normal operation, i.e., in the standard clock sequence of a CCD sensor, the image integration time is approximately 20 ms. The image is clocked into the storage zone 11b in accord therewith. For this purpose, the same number of clock pulses as lines or rows of the CCd sensor is needed. Based on a CCD sensor type having 300 lines, and a clock period of 2 μs, the image zone 11a is thus emptied after about 0.6 ms, and can then immediately accept a new image. In conventional tomographic technology, the x-ray film is moved behind the secondary diaphragm opening at a defined speed so that the image data defined by the secondary opening are integrated over a defined time span during the movement of the film. This integration of the image data is electronically simulated in the present apparatus by clocking the charge image, generated by the action of the light radiation from the scintillator layer 9 on the surface of the CCD sensor 11, out of the image zone 11a into the storage zone 11b in a defined clock sequence, and then clocking the stored image out of the storage zone 11b line-by-line via the shift register 11c. The clock sequence is selected such that the charge image, referenced to the plane of the secondary opening 8, has the same speed in the x-direction which a moving x-ray film would have in conventional tomographic technology. The clock frequency f T thus has the following relationship to the equivalent speed v of a moving film:
F.sub.t v/(n.sub.x ·a)
wherein f T is the number of lines per second and (n x ·a) is the CCD line spacing referenced to the plane of the secondary opening 8. Given a typical film speed of 30 mm/s and a line spacing of 20 μm, and based on an imaging ratio of 1:1 in the x-direction, a clock frequency of 1500 Hz results.
Further details of the procedure for image integration can be found in the aforementioned U.S. Pat. No. 4,878,234.
As mentioned above, the use of a storage zone in the CCD sensor is not absolutely necessary; the charge may be transferred from the image zone directly into the shift register line-by-line, and then clocked out from the shift register. An additional charge transfer step can thus be avoided.
For explaining the principles of the present invention, it is assumed that the CCD sensor 11 shown in FIG. 6 is subdivided into columns b 1 through b m . As previously explained, a charge image corresponding to and exposed region on a conventionally irradiated x-ray film is produced by integration and by transferring the charges in the image zone 11a. The charges are shifted from one CCD line to the next column-by-column, and are clocked out into the storage 11b, or directly into a shift register 11c. The speed with which this transfer ensues is prescribed by the shift clock frequency. A sharply imaged sliced will be obtained if this frequency f corresponds to the following relationship:
f=(v/a)(d/(1-d))
wherein d is the distance of the film from the subject, 1 is the distance of the film from the radiation source, v is the speed of the radiation source perpendicular to the subject, a is the CCD line width, and f is the clock frequency.
The product (a·f) corresponds to the film speed in conventional x-ray exposure technology.
As shown in FIG. 7, some of the CCD columns b 1 through b m are driven with different clock frequencies t 1 through t k . Each clock frequency corresponds to an exposure. The clock drive can be uniformly distributed over the entire CCD sensor, however, it is advantageous to concentrate the different drive of the columns at specific surface regions of the CCD sensor (or specific regions of the secondary diaphragm slot) if a plurality of CCD sensor elements cover the secondary slot. Such a concentration on the specific surface regions can be used to obtain a plurality of tomograms corresponding to respectively different jaw slices within an imaging region. The generation of a plurality of tomograms will result in a slight reduction in the image resolution in comparison to the generation of one tomogram corresponding to the a single slice. Therefore the region wherein the reduction in image resolution occurs due to the generation of a plurality of tomograms can be limited, with the remainder of the panorama tomogram having normal resolution.
FIG. 7 shows such a concentration at the upper surface section of the CCD sensor 11a. In this embodiment, the columns b 2 , b 4 , b 6 , b 8 and b 10 are driven with the clock frequency t 1 , the columns b 3 , b 7 and b 11 are driven with the clock frequency t 2 , and the columns b 1 , b 5 , b 9 and b 12 , and any further columns, are driven with the clock frequency t 3 . This means that the columns in the upper section of the CCD sensor are driven with three different clock frequencies corresponding to different slices, whereas the CCD sensor is driven with only one clock frequency beginning with the 12th column. In the embodiment of FIG. 7, three different slices corresponding to the clock frequencies t 1 , t 2 and t 3 can thus be acquired in the upper image section, whereas only one slice, namely the slice corresponding to the clock frequency t 3 , is imaged in the lower image section.
The columns driven with the same clock frequency are preferably combined in groups, however, it is possible to drive each column individually. Each column has a corresponding clock input which, as shown in FIG. 4, is connected to the clock generator 22.
The clock frequencies t 1 through t k can be preferably divided so that the curved slice, rather than a planar slice, of the jaw is acquired. The computer 21 and the image processing unit 17 can portray all desired slices independently of each other, and further, intermediate slices can be calculated. A plurality of slices may also be combined into one slice having a greater range of depth of field.
Variation of the range of the depth of field can be achieved by varying the width of the active sensor surface. In accordance with the principles of the present invention, the width of a column in the CCD sensor can be "artificially" influenced during an exposure by rendering passive those CCD lines which lie at the edge of an image zone. The passivation or separating of lines can be achieved by dissipating charges into the substrate (ground) of the CCD sensor. Such an electrical decoupling of the charges can be preferably done by integrating analog switches on the CCD sensor. These switches are externally activated by corresponding signal lines. The active CCD sensor surface can be influenced by appropriate activation, with a larger active sensor surface corresponding to a smaller range of depth of field.
On possibility for decoupling charges is described in FIGS. 8 through 10. This technique can be used with a CCD sensor having a separate image zone and storage zone, or with a CCD sensor having no storage zone.
FIG. 8 schematically shows the arrangement of the photo-sensitive cells and electrodes of a CCD sensor. It is assumed that every pixel of a CCD sensor is composed of four regions. These regions are:
the photo-sensitive cells a 11 , a 12 , a 13 . . . a 1n , which are shown under one another in each column b 1 , b 2 . . . b m in the illustration for n lines;
the inhibiting electrodes c 11 , c 12 , c 13 . . . c 1n for each cell having terminals (not shown) for controlling the decoupling;
the potential wells d 1 , d 2 . . . d m into which the charges are "extracted" after decoupling and are conducted to ground (i.e., the substrate of the CCD sensor); and
the separating zones e 1 , e 2 . . . e n between the individual columns, b 1 , b 2 . . . b m .
As shown in FIGS. 9 and 10, the four regions are at four different voltage potentials U, with the points of the arrows in FIGS. 9 and 10 indicating a higher voltage potential.
Normally the charge flows line-by-line (lines 1, 2 . . . n) from a 11 , a 12 . . . a 1n to the image storage zone, or directly to the shift register if an image storage zone is not present. The distribution of the voltage potentials for these four regions is shown in FIG. 9 in this condition.
When the inhibiting electrode is activated at a specific location, for example, at c 13 , this being done by a signal supplied thereto via a corresponding terminal, then all charge from a 11 through a 13 falls into the potential well d 1 , resulting in this charge being quenched. This condition is schematically shown in FIG. 10.
By selectively driving specific inhibiting electrodes, the charge transfer to a specific location of the image plane can be interrupted, and the range of the depth of field can thereby be varied.
Although modifications and changes may be suggested by those skilled in the art, it is the intention of the inventors to embody within the patent warranted hereon all changes and modifications as reasonably and properly come within the scope of the their contribution to the art. | A dental x-ray diagnostics installation for producing panorama tomograms of the jaw of a patient has clocked CCD sensors which generate electrical signals proportional to the radiation intensity thereon, and which are operated at a speed to simulate a moving x-ray film. For the purpose of simultaneously acquiring exposures of a number of different jaw slices at different depths of field during one exposure, at least some of the CCD columns are driven with different clock frequencies by separate clock inputs. | 0 |
FIELD OF THE INVENTION
The present invention relates to therapeutic patient treatment systems. More particularly, the invention relates to an interface pressure relieving mattress overlay specifically adapted to address issues peculiar to the operating room theatre, including the need for stable positioning of a patient utilizing only highly radiolucent structures.
BACKGROUND OF THE INVENTION
The medical arts have long known the necessity of therapeutic patient treatment surfaces for the support of patients exhibiting one or more risk factors for skin deterioration. In fact, unless an individual patient has no indication of skin breakdown, it is now standard of care to place the patient on an interface pressure-minimizing surface. Because of prolonged pressure exerted over specific skin surfaces while under anesthesia, however, surgical patients in particular are at risk for ulcer formation even though otherwise exhibiting no predisposing factor. As a result, it is generally regarded as standard of care practice to, whenever possible, provide some pressure-reducing surface below all patients undergoing any one of all but the shortest of anesthesia-indicating procedures.
In practice, the surgical patient requiring interface pressure reduction has most often been supported upon a thin overlay of foam or gel-containing cushions placed atop the mechanical operating table. Because such overlays have been designed to support heavy patient loads and to be radiolucent, they are typically less than three inches in thickness. This thickness provides only marginally adequate interface pressure reduction, however, and as a result, some interest has developed in the use of thicker cushions. To this end, non-hollow plastic beads and silicon mixtures have been added to gels for use in surgical overlay cushions in an effort to increase radiolucence. Unfortunately, this practice has not succeeded in eliminating the dramatic increase in X-ray power levels that may be required when thicker cushions are employed. In an attempt to address the problem of excessive radiation levels during surgery, some attention has been directed toward the development of air surfaces for use in the operating room theatre. While such systems are known to produce very low interface pressures and are extremely radiolucent, they unfortunately present some severe disadvantages when utilized in the surgical setting. Of primary concern, air surfaces tend not to provide the necessary stability for the conduct of surgical procedures. With an air surface, it is difficult to position and hold the patient in any posture other than prone or supine. In many cases, support packs must be used to prop the patient. Unfortunately, however, the solution is not so simple; because air surfaces can be very smooth, such support packs may be subject to lateral displacement during the surgical procedure.
Additionally, air surfaces are susceptible to needle sticks and scalpel cuts. With sizeable scalpel cuts, resulting damage can deflate the support surface mid-procedure, which is extremely inconvenient for the surgical team.
Finally, most air surfaces are often powered and thus dictate the additional deployment of ancillary equipment. It is well known that such additional clutter is to be avoided in the operating room, if at all possible.
With the foregoing deficiencies of the prior art in mind, it is a primary object of the present invention to improve over the prior art by providing a mattress overlay for use with an operating room table that addresses issues of skin breakdown without compromising patient stability upon the surface or necessitating increased radiation exposure.
SUMMARY OF THE INVENTION
In accordance with the foregoing objects, the present invention—a pad or mattress overlay for use atop a conventional operating room table—generally comprises at least one pad, having a chamber for containing a quantity of fluid, for supporting a patient; a deformable and pressure compensating, radiolucent fluid contained within the chamber; and wherein the chamber and the fluid are cooperatively adapted to substantially minimize interface pressure and shear force between the pad and the patient supported thereon. In the preferred embodiment, the fluid comprises glass microspheres which increase its radiolucence.
In at least one embodiment, the chamber and the fluid are further cooperatively adapted to maintain the patient in fixed position upon said pad. To this end, the fluid is characterized as being flowable in response to substantially continuously applied pressure, but essentially non-flowable in the absence of such pressure and the chamber comprises a dual-layer, urethane envelope. The envelope has an upper portion and a lower portion and the chamber is removably affixed to a base member, preferably a foam board. Because in the preferred embodiment of the present invention the envelope is chemically adhered to the foam board, the lower portion is constructed from thicker urethane sheets than is the upper portion.
In at least one embodiment, a plurality of fluid-filled chambers are provided and any one of the fluid-filled chambers may be removed from the base member and replaced without damage to any other of the fluid-filled chambers. The mattress overlay also comprises a cover sheet having a urethane outer portion and a nylon inner portion. This cover sheet is preferably removably attachable about the fluid-filled chambers and comprises an entry for selective access to the fluid-filled chambers. This entry may comprise a zipper, preferably hidden beneath a flap in order to improve the contamination resistant characteristics of the mattress overlay.
In another embodiment, however, preferred for transplant and other surgeries involving large amounts of patient fluids, the cover sheet is seam-sealed about the fluid-filled bladders. In this embodiment, the cover sheet further comprises a check valve for allowing substantially uninhibited outward airflow but only very slow, filtered inward airflow. In this manner, the check valve is adapted to prevent inward flow of liquids.
Finally, many other features, objects and advantages of the present invention will be apparent to those of ordinary skill in the relevant arts, especially in light of the foregoing discussions and the following drawings, exemplary detailed description and appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
Although the scope of the present invention is much broader than any particular embodiment, a detailed description of the preferred embodiment follows together with illustrative figures, wherein like reference numerals refer to like components, and wherein:
FIG. 1 is a perspective view of the mattress overlay of the preferred embodiment of the present invention as employed atop a conventional operating room table;
FIG. 2 is a partially cut away top plan view of the torso pad of the mattress overlay of FIG. 1 showing, in particular detail, the arrangement of some of the fluid bladders in the sacral region of the pad;
FIG. 2A is a partially cut away side plan view of the torso pad of FIG. 2 showing, in particular, the arrangement of the fluid bladders upon the foam base of the pad and the positioning of the attaching means by which the cover of the pad is affixed thereto;
FIG. 3 is a partially cut away top plan view of the head pad of the mattress overlay of FIG. 1 showing, in particular, the arrangement of some of the fluid bladders contained therein;
FIG. 4 is a partially cut away top view of the foot pad of the mattress overlay of FIG. 1 showing, in particular, the arrangement of some of the fluid bladders contained therein;
FIG. 5 is a partially cut away top view of arm board pad of the mattress overlay of FIG. 1 showing, in particular, the arrangement of some of the fluid bladders contained therein; and
FIG. 5A is a partially cut away side view of the arm board pad of FIG. 5 showing, in particular, details of the attachment of the arm board pad to the operating table used therewith.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Although those of ordinary skill in the art will readily recognize many alternative embodiments, especially in light of the illustrations provided herein, this detailed description is exemplary of the preferred embodiment of the present invention, the scope of which is limited only by the claims appended hereto.
Referring now to FIG. 1, the preferred embodiment of the mattress overlay 10 of the present invention is shown to generally comprise a complete pad replacement system adapted for universal use with a variety of conventional operating room tables 11 . As is well-known to those of ordinary skill in the art, such operating room tables 11 typically comprise a plurality of articulating sections supported atop a stable base 24 . An exemplary table, similar to that shown in FIG. 1, is commercially available through the Steris Corporation of Mentor, Ohio under the trade designation “AMSCO 2080.”
As will be better understood further herein, the mattress overlay 10 of the present invention is self-adjusting to support a wide weight range of patients with great stability and very little X-ray attenuation. The mattress overlay 10 of the preferred embodiment of the present invention comprises a torso pad 12 , head pad 13 , foot pad 14 and one or two arm board pads 15 . It will be understood by those of ordinary skill in the art, however, that many of the objects of the present invention may be achieved through implementations comprising as few as one of the pads 12 , 13 , 14 , 15 .
Referring now to FIGS. 2 and 2A, the torso pad 12 of the present invention is described in detail as exemplary of each of the pads 12 , 13 , 14 , 15 of the mattress overlay 10 . As shown in the figures, each pad 12 , 13 , 14 , 15 generally comprises a plurality of fluid-filled bladders 17 arranged upon a foam base 16 and encased within a cover 19 . As detailed further herein, each fluid bladder 17 comprises a dual-layer urethane chamber containing a necessary quantity of deformable and pressure compensating fluid. According to the present invention, this fluid is characterized as being flowable in response to substantially continuously applied pressure but essentially non-flowable in the absence of such pressure. In the preferred embodiment of the present invention, a fluid as is commercially available in Applicant's RIK Mattress system or as described in U.S. Pat. No. 4,728,551 issued Mar. 1, 1998 to Jay is utilized. By this reference, the full disclosure of U.S. Pat. No. 4,728,551, including the claims, is incorporated herein as though now set forth in its entirety. Although less preferred, other fillers may also be utilized instead of the preferred fluid while still falling within the scope of certain aspects of the present invention. One such alternative filler may be the filler material described in U.S. Pat. Nos. 5,421,874, 5,549,743, and 5,626,657.
Because the fluid utilized in the preferred embodiment of the present invention comprises glass microspheres the overlay 10 constructed therewith is highly radiolucent. As a result, Applicant has found that pads 12 , 13 , 14 , 15 with thickness on the order of three inches or more may be implemented without requiring overly increased X-ray power levels during surgical use. In test, Applicant has been able to achieve 2 mm Al performance, within the established standard for surgical pads, with only 60 kV at 8 mA power. This X-ray performance is well within the requirements for orthopedic surgeries and necessitates only slight power boosting for microsurgical applications. Consequently, the overlay 10 constructed according to the teachings of the present invention is able to provide excellent interface pressure relief without exposing the patient to unnecessarily hazardous radiation levels.
It should be noted that although the maximum benefit of the present invention is obtained utilizing a fluid as hereinabove described, other substantial equivalents may be possible. It may also be possible to appreciate many aspects of the present invention utilizing other fill materials. For example, U.S. Pat. No. 5,592,706 issued to Pearce on Jan. 14, 1997 and U.S. Pat. No. 5,829,081 issued to Pearce on Nov. 3, 1998 each describe bladders filled with a fluid of a nature that may be utilized, with only corresponding sacrifice in performance, in the present invention. By this reference, therefore, the full disclosures of U.S. Pat. No. 5,592,706 and U.S. Pat. No. 5,892,081 are incorporated herein as though now set forth in their respective entireties.
As shown in FIGS. 2 through 5A, each of the fluid-filled bladders 17 is generally rectangular in form. As also shown, a plurality of the fluid-filled bladders 17 is arranged as necessary to form the general shape of each pad 12 , 13 , 14 , 15 of the mattress overlay 10 . According to the preferred embodiment of the present invention, fourteen bladders 17 are arranged within the torso pad 12 ; six bladders 17 are arranged within the head pad 13 ; twelve bladders 17 are arranged within the foot pad 14 ; and four bladders 17 are arranged within each arm board pad 15 . As will be apparent to those of ordinary skill in the art, each bladder 17 may be sized as required to form each pad 12 , 13 , 14 , 15 and greater or fewer bladders 17 may be utilized. Those of ordinary skill in the art will also recognize, however, especially in light of the disclosures made herein, that the number of bladders 17 utilized and the dimensions thereof will directly affect the performance to of the present invention.
As mentioned hereinabove, each fluid-filled bladder 17 comprises a dual-layer urethane covering. This dual-layer urethane covering has been found to give each fluid-filled bladder 17 a self-sealing characteristic wherein bladder failure due to needle sticks and the like is essentially eliminated. This is due, at least in part, to the utilization of a fluid as previously described. Because each fluid-filled bladder 17 is preferably adhered directly to the foam base 16 of one of the pads 12 , 13 , 14 , 15 , Applicant has found it desirable to construct each fluid-filled bladder 17 with four sheets of urethane, each cut to shape and then perimetrically sealed. In this manner, a lighter weight urethane may be utilized for the upper layers, which are in closest proximity to the patient, while a heavier weight urethane may be utilized for the lower layers, which must bear the adhesive. The fluid, as previously described, is contained between the second and third layers.
Each pad 12 , 13 , 14 , 15 is contained within a cover 19 generally comprising a two-layer sheet having a urethane outer portion and a nylon inner portion. Although those of ordinary skill in the art will recognize that this configuration goes directly opposite the teachings of prior art designs, Applicant has found this configuration desirable in that it provides a highly stain-resistant surface even in the presence of heavy betadyne usage. The surface is also fluid impermeable, anti-static, anti-bacterial and, when properly encasing the pad, the cover 19 provides for wipe-down sterilization. As shown particularly in FIGS. 2A and 5A, the cover 19 is preferably removably attached to each pad 12 , 13 , 14 , 15 . In this manner, each bladder 17 may be easily accessed for repair or replacement as necessary or the entire cover 19 may be replaced if required. As shown, a zipper 28 or equivalent attachment means is preferably provided beneath a flap 27 toward the bottom of each pad 12 , 13 , 14 , 15 . Protection in this manner will aid in preventing contamination, even in the presence of heavy patient fluid flows.
As also shown in FIGS. 2A and 5A, the various pad 12 , 13 , 14 , 15 each comprise a means 21 for attachment of the pad 12 , 13 , 14 , 15 to the operating room table 11 . According to the preferred embodiment of the present invention, this attachment 12 comprises a plurality of nylon straps 25 , each strap 25 further comprising a patch 26 of hook or loop type material such as that commercially available under the well-known trademark “VELCRO.” In preparation for use, each pad 12 , 13 , 14 , 15 is placed upon the appropriate articulating section 23 of the operating room table 11 and then secured in place with its respective strap 25 .
As shown in the various figures, the covers 19 fit loosely over each pad 12 , 13 , 14 , 15 to generally present a wrinkled interface with the patient surface. Likewise, each fluid-filled bladder 17 is only partially filled, thereby resulting in a similarly wrinkled upper surface. Those of ordinary skill in the art, however, will recognize that wrinkles beneath the patient have to date been generally regarded as hazardous, having been shown to contribute to skin breakdown. In fact, with prior art designs, a great deal of attention from the surgical team has been required for the continuous removal of wrinkles from the patient-supporting surface. Although wrinkle control has been a perplexing issue in the prior art, necessary to prevent occlusion of capillary blood flow, this is not the case with the present invention. In the present invention, the bladders 17 as filled with a fluid of the characteristics hereinabove described are so conformable to the patient that wrinkles do not impede capillary blood flow. As a result, wrinkles in the patient-supporting surfaces may be advantageously used to eliminate shearing forces, thereby preventing skin breakdown. This ability to reduce shearing forces is a major advantage of the present invention as compared to previously known operating room table pad systems.
In test, the present invention has resulted in greatly reduced incidence of skin breakdown, even for patients undergoing very prolonged operations, and less patient discomfort in the post-operative recovery period. In one series of uses for head and neck cancer surgery, involving the grafting of skin from the legs to the head and neck area for reconstruction, the skin breakdown incidence was reduced from an average of 40%, with prior art pads, to zero. In this series of tests, the mean surgery length was 17 hours, with a maximum length of 32 hours. The mattress overlay 10 of the present invention is able to achieve such results due to the fact that the patient can be nearly completely immersed in the fluid with almost total conformation of the patient-interfacing surface to the patient's body, including the most bony prominentia. Because the fluid as hereinabove described is very viscous, the patient supported upon the overlay 10 of the present invention remains very stable even when torqued by the surgeon into a very unnatural position. The great stability offered by the present invention and the pressure reducing capabilities thereof, especially when coupled with the high radiolucence exhibited, make clear that the teachings of the present invention represent an important and significant development in the art.
In use, the various pads 12 , 13 , 14 , 15 of the mattress overlay 10 are generally placed upon the articulating sections 23 of the operating room table 11 and secured in place. The patient is then placed atop the mattress overlay 10 and positioned by the surgeon as desired for the surgical procedure. As has been discussed, patient placement is greatly enhanced by the stable nature of the pads 12 , 13 , 14 , 15 as implemented according to the teachings of the present invention. In an extension of these teachings, Applicant has found that due to the highly conformable nature of the fluid-filled bladders 17 , the foam base 16 of the head pad 13 may be removed whereafter upon removal of the articulating section 23 of the head region the patient's head may be placed upon the surgeon's lap with only the modified head cushion 13 interposed therebetween. In this alternative embodiment, the fluid-filled bladders 17 conform to both the patient's head and the surgeon's lap enabling the surgeon to position the head through leg movement while keeping both hands free for the easier performance of the surgical procedure. This type of lap surgery has been successfully performed in the pediatric oral surgery arena and has resulted in control and stability not attainable through the use of gel packs or other cushions.
While the foregoing description is exemplary of the preferred embodiment of the present invention, those of ordinary skill in the relevant arts will recognize the many variations, alterations, modifications, substitutions and the like as are readily possible, especially in light of this description, the accompanying drawings and claims drawn thereto. For example, the zipper 28 of the cover attachment 20 may be replaced in an embodiment comprising a seam-sealed cover 19 . This type of cover 19 is advantageous for use in surgeries involving extreme amounts of fluids such as, for example, organ transplants, which require a great deal of organ cleaning. In implementing such an embodiment, a one-way check valve 29 is preferably inserted into the cover 19 for the uninhibited outward escape of air and allowing only for a very slow intake of filtered air. Such a valve 29 serves to retain the immersion qualities of the system while simultaneously enabling greater immunity from surgical fluid contamination. In any case, because the scope of the present invention is much broader than any particular embodiment, the foregoing detailed description should not be construed as a limitation of the scope of the present invention, which is limited only by the claims appended hereto. | A patient supporting surface for use with a conventional operating room table having at least one pad for supporting a patient, wherein the pad has a chamber for containing a quantity of fluid. The chamber is a dual-layer, urethane envelope having an upper and lower portion. The fluid contained within the chamber is a deformable and pressure compensating, radiolucent fluid. The chamber and the fluid are cooperatively adapted to maintain the patient in a fixed position while substantially minimizing the interface pressure and shear force between the pad and the patient. A cover sheet may be removably attachable about the fluid-filled chambers and comprises an entry for selective access to the fluid-filled chambers. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present invention claims the benefit of U.S. Provisional Patent Application No. 61/147,747, filed Jan. 27, 2009, and entitled “TRANSIENT ABSORBER FOR POWER GENERATION SYSTEM”, U.S. Provisional Patent Application No. 61/147,748, filed Jan. 27, 2009, and entitled “WEATHER RESPONSIVE TREADLE LOCKING MEANS FOR POWER GENERATION SYSTEM”, U.S. Provisional Patent Application No. 61/147,749, filed Jan. 27, 2009, and entitled “LOW PROFILE, SURFACE-MOUNTED POWER GENERATION SYSTEM”, U.S. Provisional Patent Application No. 61/147,750, filed Jan. 27, 2009, and entitled “VEHICLE SPEED DETECTION MEANS FOR POWER GENERATION SYSTEM”, U.S. Provisional Patent Application No. 61/147,752, filed Jan. 27, 2009, and entitled “RECIPROCAL SPRING ARRANGEMENT FOR POWER GENERATION SYSTEM”, and U.S. Provisional Patent Application No. 61/147,754, filed Jan. 27, 2009, and entitled “LOSSLESS SHORT-DURATION ELECTRICAL STORAGE MEANS FOR POWER GENERATION SYSTEM”, the entire contents of which are incorporated herein by reference in their entirety.
FIELD OF THE INVENTION
[0002] The present invention is directed toward devices and methods of harvesting vehicle energy, and more specifically, toward a vehicle speed detection means for harvesting vehicle energy.
SUMMARY OF THE INVENTION
[0003] These problems and others are addressed by the present invention, which provides a novel vehicle energy harvester that overcomes many of the issues with the conventional devices and is therefore better suited for real-world implementation than the conventional devices.
[0004] The exemplary embodiments of the invention make productive use of the energy that is normally wasted (in the form of heat) in reducing the speed of motor vehicles on exit ramps, toll plazas etc., etc. The vehicle energy harvester can absorb mechanical energy from passing (or breaking) vehicles and convert the mechanical energy to electrical energy using, for example, shaft driven generators.
[0005] The disclosed embodiments provide a vehicle energy harvester and power generation system that is simple to install, provides a short payback period, and has a scalable configuration. More particularly, the disclosed embodiments can provide a simple and reliable mechanical configuration that can withstand sever environments. The low cost configuration of the system may provide for faster payback of the expense of the system, and therefore, make the system more practical and desirable for practical applications.
[0006] Additionally, the ease with which the system can be installed also may make the system more practical and desirable for practical applications. The disclosed embodiments require little or no excavation and can be installed in a few hours, instead of over several days as with conventional devices.
[0007] The disclosed embodiment also can provide a scalable configuration that may be particularly advantageous for use at locations, such as exits ramps, toll plazas, hills, among other locations.
[0008] Furthermore, the exemplary embodiments can include a vehicle speed sensor. The embodiments can provide important advantages. For example, the exemplary unit can be used on exit ramps and other traffic lanes where motor vehicles approaching at a high rate of speed are required to reduce speed to comply with local road/traffic conditions. In normal operation, the disclosed embodiments can absorb a small portion of a vehicle's kinetic energy and convert it to electrical energy. In cases where slower moving vehicles are traveling at or below the local speed limit on the exit ramp, it may be desirable to allow such vehicles to pass unimpeded and not slow them any further.
[0009] An exemplary embodiment of the invention is directed to, for example, a vehicle energy harvester including a subunit having an upper surface forming a roadway surface, a vehicle activated treadle on the subunit, the vehicle activated treadle moveable between a first position in which an upper surface of the treadle is at an angle with respect to the upper surface of the roadway surface and a second position in which the upper surface of the treadle is flush with the upper surface of the roadway surface, a generator that generates power in response to movement of the vehicle activated treadle, and a vehicle speed detection device that detects a speed of a vehicle travelling over the roadway surface based on a speed of movement of the vehicle activated treadle.
[0010] Another exemplary embodiment of the invention is directed to, for example, a vehicle energy harvester comprising a plurality of subunits each having an upper surface forming a roadway surface, a vehicle activated treadle on at least one of the plurality of subunits, the vehicle activated treadle moveable between a first position in which an upper surface of the treadle is at an angle with respect to the upper surface of the roadway surface and a second position in which the upper surface of the treadle is flush with the upper surface of the roadway surface, a generator that generates power in response to movement of the vehicle activated treadle, and a vehicle speed detection device that detects a speed of a vehicle travelling over the roadway surface based on a speed of movement of the vehicle activated treadle.
[0011] Another exemplary embodiment of the invention is directed to, for example, a vehicle energy harvester comprising a subunit having an upper surface forming a roadway surface, a vehicle activated treadle on the subunit, the vehicle activated treadle moveable between a first position in which an upper surface of the treadle is at an angle with respect to the upper surface of the roadway surface and a second position in which the upper surface of the treadle is flush with the upper surface of the roadway surface, a generator that generates power in response to movement of the vehicle activated treadle, and vehicle speed detection means for detecting a speed of a vehicle travelling over the roadway surface based on a speed of movement of the vehicle activated treadle.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] These and other aspects and features of embodiments of the present invention will be better understood after a reading of the following detailed description, together with the attached drawings, wherein:
[0013] FIGS. 1 is a schematic top view of a power absorber unit of a vehicle energy harvester.
[0014] FIG. 2 is a schematic perspective view illustrating a portion of a vehicle energy harvester.
[0015] FIG. 3 is a schematic side view of a vehicle energy harvester having vehicle speed detection means.
[0016] FIG. 4 is a schematic top view of a vehicle energy harvester having vehicle speed detection means.
DETAILED DESCRIPTION
[0017] The present invention now is described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.
[0018] Referring now to the drawings, FIGS. 1-4 illustrate an exemplary vehicle energy harvester 10 .
[0019] The exemplary embodiments can make productive use of the energy that is normally wasted (in the form of heat) in reducing the speed of motor vehicles on exit ramps, toll plazas etc., etc. The vehicle energy harvester 10 can absorb mechanical energy from passing (or breaking) vehicles and convert the mechanical energy to electrical energy using, for example, shaft driven generators. Other means for converting the mechanical energy to electrical energy also are contemplated. In an exemplary embodiment, the electric power from the generators can be converted, metered, and fed into the commercial power grid. In another exemplary embodiment, each site can be equipped with wireless communications to monitor the status and/or output of the system.
[0020] Power Absorber Configuration
[0021] The disclosed embodiments can include individual assemblies with integral generators. Other generator configurations also are possible, such as separate generators.
[0022] As shown in FIG. 1 , the vehicle energy harvester unit 10 can be a low-profile surface mounted assembly. The vehicle energy harvester unit 10 can include an entry ramp 12 and an exit ramp 14 . The vehicle energy harvester unit 10 can include a plurality of subunits 16 having a top surface or driving surface 17 . Each subunit can include one or more vehicle activated treadles 18 . In an embodiment, each subunit 16 can include a generator unit 20 .
[0023] In other embodiments, the vehicle energy harvester unit 10 can be set into the road surface. The surface mounted assembly may require minimal installation effort. Additionally, the unit count can be scaled to road/breaking needs. In an embodiment, each generator unit 20 can feed a common power summing/conversion unit 22 . A simple cable interconnect 24 can be provided to connect each generator unit 20 to the common power summing/conversion unit 22 . A fail safe configuration can protect the system against individual unit failures.
[0024] Power Conversion Unit
[0025] In a disclosed embodiment, the individual absorber units 16 can be connected via cable assemblies 24 . The input power can be summed and applied to a low-loss inverter unit. The power can be converted immediately to a form that is transmittable to the power grid. The output can be metered and applied to the power grid for transmission.
[0026] Absorber Unit Operation
[0027] With reference to FIG. 2 , an exemplary embodiment of a subunit 16 of a vehicle energy harvester unit 10 can include spring-loaded treadles 18 having a treadles gear 30 engaging a drive gear 32 . The drive gear 32 is coupled to a shaft 34 . In operation, one or more vehicle tires force the spring-loaded treadles 18 down as they roll over the treadles 18 . The treadle gears 30 drive the plurality of drive gears 32 , which rotate the shaft 34 . The shaft 34 winds a torsion spring 36 , thereby absorbing the treadle drive transient. A pawl can lock the shaft 34 as rotation ends. The torsion spring 36 rotates a flywheel 38 , thereby spreading the impulse of the treadle drive over time to extend output to a generator 40 . The flywheel 38 can turn a generator 40 , such as a hydro pump. The generator 40 , in turn, can generate electric power for sale/use/storage.
[0028] Vehicle Speed Detection Means
[0029] Referring now to FIGS. 3 and 4 , an exemplary embodiment of a vehicle energy harvester 10 having vehicle speed detection means will now be described.
[0030] The present invention recognizes that the known conventional devices do not have a means for determining the speed of oncoming vehicles. The embodiments of the invention address and solve these problems and improve the utility of a treadle based energy conversion systems according to the embodiments of the invention.
[0031] The exemplary embodiments can provide important advantages in that vehicles traveling faster than the posted speed limit can be slowed by the vehicle energy harvester unit 10 and a portion of the vehicle's kinetic energy can be converted to electricity rather than wasted as heat from the vehicles braking system. Conversely, vehicles traveling at or below the posted speed limit can be allowed to pass unimpeded.
[0032] An exemplary embodiment provides a vehicle energy harvester unit 10 that can be used, for example, on exit ramps and other traffic lanes where motor vehicles approaching at a high rate of speed are required to reduce speed to comply with local road/traffic conditions. In normal operation, the embodiments of the vehicle energy harvester unit 10 can absorb a small portion of a vehicle's kinetic energy and convert it to electrical energy. In cases where slower moving vehicles are traveling at or below the local speed limit on the exit ramp, it may be desirable to allow such vehicles to pass unimpeded and not slow them any further. The exemplary vehicle energy harvester unit 10 can be equipped with vehicle speed detection means, such as a vehicle speed sensor or the like, to accomplish this function. Various technologies have been considered and contemplated to perform this function and several examples thereof are illustrated and described in FIGS. 3 and 4 .
[0033] As shown in FIG. 3 , an exemplary embodiment of the vehicle energy harvester unit 10 can include vehicle speed detection means or a vehicle speed detection assembly having, for example, an infrared (IR) emitter 50 , an infrared (IR) detector 52 , and a rotating arm portion 54 coupled to the treadle 18 . Other known devices for detecting the speed of a moving part can be used to detect the velocity of the movement of the treadle.
[0034] In operation, the infrared (IR) detector 52 can detect an infrared beam from the infrared (IR) emitter 50 . The rotating arm portion 54 can be configured to interpose the infrared (IR) emitter 50 and the infrared (IR) detector 52 during movement of the treadle 18 . The rotating arm portion 54 of the treadle 18 can include one or more apertures 56 for permitting the infrared beam emitted from the infrared (IR) emitter 50 to pass through the rotating arm portion 54 of the treadle 18 and be detected by the infrared (IR) detector 52 . In operation, as the treadle 18 moves downward, the infrared beam from the infrared (IR) emitter 50 can be broken by the rotating arm portion 54 of the treadle 18 and the disruption of the infrared beam can be detected by the infrared (IR) detector 52 . The infrared beam can then be detected again by the infrared (IR) detector 52 as the apertures 56 in the rotating arm portion 54 pass by (i.e. correspond to) the infrared beam. In an embodiment, the time between the beams being detected by the infrared (IR) detector 52 can be used to calculate the speed of the vehicle entering the ramp 12 . The speed information can be used by the microcontroller unit (MCU) to engage or disengage one or more of the treadle subunits 16 depending on the calculated speed of the vehicle.
[0035] As shown in FIG. 4 , an exemplary embodiment of the vehicle energy harvester unit 10 can include one or more treadles 50 on the entry ramp 12 . The treadles 50 can include vehicle speed detection means or a vehicle speed detection assembly, for example, as illustrated in FIG. 3 . In this manner, the speed of the vehicle entering the ramp 12 can be calculated and the speed information can be used by the microcontroller unit (MCU) to engage or disengage one or more of the treadle subunits 16 depending on the calculated speed of the vehicle.
[0036] The present invention has been described herein in terms of several preferred embodiments. However, modifications and additions to these embodiments will become apparent to those of ordinary skill in the art upon a reading of the foregoing description. It is intended that all such modifications and additions comprise a part of the present invention to the extent that they fall within the scope of the several claims appended hereto.
[0037] Like numbers refer to like elements throughout. In the figures, the thickness of certain lines, layers, components, elements or features may be exaggerated for clarity.
[0038] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the specification and relevant art and should not be interpreted in an idealized or overly formal sense unless expressly so defined herein. Well-known functions or constructions may not be described in detail for brevity and/or clarity.
[0039] As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. As used herein, phrases such as “between X and Y” and “between about X and Y” should be interpreted to include X and Y. As used herein, phrases such as “between about X and Y” mean “between about X and about Y.” As used herein, phrases such as “from about X to Y” mean “from about X to about Y.”
[0040] It will be understood that when an element is referred to as being “on”, “attached” to, “connected” to, “coupled” with, “contacting”, etc., another element, it can be directly on, attached to, connected to, coupled with or contacting the other element or intervening elements may also be present. In contrast, when an element is referred to as being, for example, “directly on”, “directly attached” to, “directly connected” to, “directly coupled” with or “directly contacting” another element, there are no intervening elements present. It will also be appreciated by those of skill in the art that references to a structure or feature that is disposed “adjacent” another feature may have portions that overlap or underlie the adjacent feature.
[0041] Spatially relative terms, such as “under”, “below”, “lower”, “over”, “upper”, “lateral”, “left”, “right” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is inverted, elements described as “under” or “beneath” other elements or features would then be oriented “over” the other elements or features. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the descriptors of relative spatial relationships used herein interpreted accordingly. | A vehicle energy harvester including a subunit having an upper surface forming a roadway surface; a vehicle activated treadle on the subunit, the vehicle activated treadle moveable between a first position in which an upper surface of the treadle is at an angle with respect to the upper surface of the roadway surface and a second position in which the upper surface of the treadle is flush with the upper surface of the roadway surface; a generator that generates power in response to movement of the vehicle activated treadle; and a vehicle speed detection device that detects a speed of a vehicle travelling over the roadway surface based on a speed of movement of the vehicle activated treadle. | 7 |
REFERENCE TO RELATED DISCLOSURE
This application makes reference to and incorporates Disclosure Document No. 414148, entitled PISTOL FRONT HANDLE AIMING IMPROVEMENT DEVICE, filed in the U.S. Pat. & Trademark Office on Feb. 21, 1997.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to ordnance, and, more specifically, the present invention relates to handles of small bore, short barrel ordnance.
2. Discussion of the Related Art
Currently, one or two hands are used to aim a handgun. Unfortunately, even when two hands are used, maintaining the requisite horizontal and vertical control over the firearm is difficult. The primary reason for this difficulty is inherent in the design of a conventional handgun. Specifically, handguns are configured to be relatively small, as compared with rifles, and have a single, hand-sized handle by which a user grips the handgun. This singular point of contact does not lend to easy control and aiming of the handgun.
Exemplars of contemporary practice in the prior art fall into two groupings. The first grouping includes those devices that are permanently attached to a firearm. For example, U.S. Pat. No. 4,271,623 to Beretta, entitled Pistol With Stock Extension And Auxiliary Grip, describes an auxiliary grip that pivots to the barrel of a handgun. U.S. Pat. No. 5,417,002 to Guerra, entitled Adjustable Firearm Handle, describes a handle extending from a bracket that slides radially about the barrel of a rifle. The bracket includes a spring-loaded lock to fix placement thereof relative to the barrel. The second grouping pertains to removable firearm devices. For example, U.S. Pat. No. 2,435,217 to Howell Jr., entitled Firearm And Stock Structure Therefor, which describes a rifle including a bayonet-type recess for a handle. Once inserted, the handle is secured to the barrel with a threaded fastener. U.S. Pat. No. 2,056,975 to Michal Jr., entitled Machine Gun And Converter Therefor, describes an auxiliary handle extending from a bracket screw-mounted on and extending beyond the barrel of a handgun. The device does not include protective structure other than necessary to support the handle.
After comprehensive analysis of the exemplars of contemporary practice in the prior art, I have found a need exists for a device that improves the ability of a user to exert horizontal and vertical control over a handgun to improve the aiming thereof.
SUMMARY OF THE INVENTION
The present invention overcomes the limitations of the prior art by providing a device which affords a user greater control over a handgun. The invention includes a guard, a handle mounted to the guard and a mounting device, mounted on the handgun, which receives and locks the guard to the handgun.
In view of the above, a first object of the invention is to provide an improved handle for a handgun.
A second object of the invention is to provide a detachable second handle for a handgun.
A third object of the invention is to provide a handle for, that is adjustable relative to, a handgun.
A fourth object of the invention is to provide an aiming device which is readily installable on a handgun.
A fifth object of the invention is to provide improved elements and arrangements thereof, in an apparatus for the purposes described, which is inexpensive, dependable and effective in accomplishing its intended purposes.
These and other objects of the present invention will become readily apparent upon further review of the following specification and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
A more complete appreciation of the invention, and many of the attendant advantages thereof, will be readily apparent as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings in which like reference symbols indicate the same or similar components, wherein:
FIG. 1 is a left side elevational view of the present invention mounted on a handgun, alternate positions of the handle thereof being shown in phantom lines;
FIG. 2 is a front elevational view of the invention mounted on a handgun;
FIG. 3 is an enlarged, partial left side elevational view, partially in cross-section, receiving the tang of the guard;
FIG. 4 is a partial plan view of the mounting device, detached from a handgun, receiving the tang of the guard;
FIG. 5 is a cross-sectional detail view of the mounting device mounted on a handgun, drawn along sectional line V--V' in FIG. 3; and
FIG. 6 is a top right front perspective view of the mounting device of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, an embodiment of the principles of the present invention constructed as shown mounted on a handgun 12. The handgun 12 has a trigger 11, a hammer 13, a near sight 15 and a far sight 17. The device 10 includes three basic components: a guard 14; a handle 16; and a mounting device 18.
Referring also to FIG. 2, the guard 14 serves two functions. First, the guard 14 must possess sufficient structural integrity to provide a user with a stable aiming platform for the handgun. Second, the guard should be configured so as to prevent inadvertent entry of the user's fingers, or other objects, from entry into the line of fire. Toward these ends, the guard 14, preferably, possesses a semi-cylindrical shape. The use of a semi-circular shape is helpful to the execution of the invention. The preferred semi-circular shape lends greater structural rigidity to the guard (than a straight bar, for example) even where thin gauge or inherently pliable materials are employed. For example, although cardboard may not be an ideal material from which to construct the guard 14, when the material is urged to assume a semi-cylindrical shape, it becomes substantially more rigid than when it assumes its natural planar state.
Second, the semi-cylindrical shape also serves to deter inadvertent intrusion of the user's fingers from blast and the accompanying hot gases attendant upon the discharge of a projectile from the barrel. Precisely what boundaries the guard 14 defines is a matter of safety and design choice.
Referring again to FIG. 1,the inner surface 19 of the guard 14 does not contact the barrel 44 of the handgun 12, as indicated by the edges 21, 23, 24, 27, 29 and 31.
The handle 16 is mounted onto the guard 14. The handle 16 provides a second point of control over the handgun 12. The handle 16 need not assume any particular configuration, so long as it possesses sufficient size and provides sufficient comfort to the user to achieve the purposes of the present invention. By grasping both handle 16 and grip 20, the user gains substantially more control over the vertical and horizontal aiming of the handgun 12 than in a case where the user may grasp only the grip 20.
The handle 16 may be mounted on the guard 14 by a number of different techniques. Preferably, threaded fasteners 24 are used to connect the handle 16 and guard 14. As shown, the guard 14 has a plurality of apertures 22 therein for receiving any number of fasteners 24. This construction permits the handle to be adjusted relative to the guard 14, such that it may assume different spatial relationships 26, 28 or 30, relative to the grip 20.
Referring also to FIGS. 3 and 4, the guard 14 has a tang 32, as shown in FIG. 1. The tang 32 accommodates a lock 34 that secures the guard 14 to the mounting device 18. Preferably, one embodiment of the lock 34 employs a clip 36 formed on the end of an extension 38 of the tang 32. The extension 38 and a non-extension portion 37 of the tang 32 define a gap 39. The extension 38 biases the clip 36 relative to the tang 32. Embodiments of this invention also may include a release button 40 mounted on the extension 38 or otherwise fixed to the clip 36. Preferably, a space 35 separates the clip 36 and release button 40.
Referring also to FIGS. 5 and 6, the mounting device 18 has a bottom 48, as shown in FIG. 5, defined by the edges 100, 102, 104 and 106, as shown in FIG. 6. The mounting device 18 has a right side 108, as shown in FIG. 5, defined by the edges 100, 110, 112 and 114, as shown in FIG. 6. The 18 has a left side 116, as shown in FIG. 5, defined by edges 104, 118, 120 and 122, as shown in FIG. 6. The mounting device has a front side 124 defined by edges 102, 110, 118, and curve 126, as shown in FIG. 6. The mounting device has a back 128 defined by edges 106, 114, 122 and curve 130, as shown in FIG. 6. A contour 52, shown in FIG. 5, is defined by the surface between curves 126 and 130, as shown in FIG. 6.
The mounting device 18 includes apertures 42 to accommodate threaded fasteners 50 that engage threaded holes 43 in the frame 132 of the handgun 12. Alternative fasteners may be used to attach the mounting device to the handgun. In this particular embodiment, access holes 46 are provided in the bottom side 48 of the mounting device 18. The access holes 46 allow for insertion of the threaded fastener 50, or like fastener elements, as well as any tool necessary to install these threaded fasteners.
The contour 52 of the mounting device 18 complements the contour, as shown in FIG. 5, of the frame 132 of the handgun 12. The mounting device 18 may assume any configuration commensurate with the handgun selected by one practicing the present invention. This contour configuration should not be interpreted as excluding other mechanisms for stabilizing the relationship between the mounting device 18 and the handgun 12. This embodiment of the invention assures that the device is stable with respect to the handgun so as to aid in the aiming of the handgun and not introduce unwanted play.
The mounting device 18 has a slot 54 configured to receive the tang 32 extending from the guard 14. The slot 54 has a first surface 500, as shown in FIG. 5, defined between edges 200 and 300, as shown in FIG. 6. The slot 54 has a second surface 502, as shown in FIG. 5, defined between edges 202 and 302, as shown in FIG. 6. The slot 54 has a third surface 504, as shown in FIG. 5, defined between edges 204 and 304, as shown in FIG. 6. The slot 54 has a fourth surface 506, as shown in FIG. 5, defined between edges 206 and 306, as shown in FIG. 6.
Referring also to FIGS. 3 and 4, the tang 32 and non-extension portion 37 present surfaces 400, 402, 404 and 406. The tang 32 should be closely received in the slot 54 so as to provide a minimum of play between tang 32 and slot 54. When received, the surfaces 400 and 500, 402 and 502, 404 and 504, and 406 and 506 are in close contact.
The mounting device 18 also has apertures 56 which are configured to receive the clips 36 of the tang 32. Each aperture 56 is defined by two continuous surfaces 600 and 604, and two discontinuous surfaces 602 and 606, as shown in FIG. 3. The discontinuity of the discontinuous surfaces 602 and 604 is occasioned by intersection with the slot 54, as described above. Continuous surface 600, as shown in FIG. 3, is defined by edges 700 and 702, as shown in FIG. 6. Continuous surface 604, as shown in FIG. 3, is defined by edges 704 and 706, as shown in FIG. 6. Discontinuous surface 602, as shown in FIG. 3, is defined by edges 708 and 710, as shown in FIG. 6. Discontinuous surface 606, as shown in FIG. 3, is defined by edges 712 and 714, as shown in FIG. 6.
Although the aperture 56 is shown having a height 58, as shown in FIG. 3, coextensive with that of the slot 54, in other embodiments, these heights may be different. Also, the aperture-and-clip convention shown and described illustrates only one possible mechanism for locking the guard 14 to the mounting device 18 and should not be construed as excluding other mechanisms.
In an operation, the user inserts the tang 32 into the slot 54 by a sufficient distance so that the clip 36 snaps into place within the aperture 56. To disassemble the device from the handgun, the user squeezes together the release buttons 40, with the user's thumb and forefinger, for example, so that the clips 36 are completely dislodged from the apertures 56, thus allowing the tang 32 to be removed from the slot 54.
It should be understood that the present invention is not limited to the particular embodiment disclosed herein as the best mode contemplated for carrying out the present invention, but rather that the present invention is not limited to the specific embodiments described in this specification except as defined in the appended claims. | A guard including a handle and having a tang received in a mounting device mounted on a handgun, providing a user with dual-handled control over the handgun. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method of preparing an InSb thin film, which is applied to a magnetic resistive element, a Hall element or the like.
2. Description of the Background Art
In general, an InSb compound semiconductor is employed as a material for a Hall element or a magnetic resistive element due to its high Hall mobility μ. A magnetic sensor such as the Hall element or the magnetic resistive element must have resistance of several hundred Ω to several kΩ in order to improve consistency with a sensor signal processing circuit. However, InSb is a material which has low resistivity of 10 -8 Ω·cm order in essence. When InSb is applied to a Hall element or a magnetic resistive element, therefore, it is necessary to form a thin film. Such formation of a thin film is also required in order to easily form a fine pattern.
In general, an InSb thin film having high mobility is formed on a mica substrate by vacuum evaporation or the like. It is empirically known that mica is the optimum material for a base material for forming a thin film of InSb. While the reason therefor is not yet clarified in detail, it is conceivable that a thin film having small reduction of mobility is formed due to excellent crystallinity of the InSb thin film which is formed on such a mica substrate.
However, it is difficult to work a final element on a mica substrate, which has cleavage in crystal structure. In general, therefore, it is necessary to temporarily form an InSb thin film on mica and transfer this InSb thin film onto a target base material for patterning the same into a prescribed shape.
An InSb film which is formed on a general substrate such as an Si substrate having an SiO 2 film, an Si substrate having a film of silicon nitrides, an Si substrate having an Al 2 O 3 film, a glass substrate, a ferrite substrate, an Si substrate of each crystal plane orientation or a GaAs substrate exhibits mobility of about 10000 to 20000 cm 2 /V·sec. Therefore, a magnetic resistive element, a Hall element or an infrared detection element which is prepared from such a film is inferior in rate of magnetic resistance change, product sensitivity and photoelectromotive force.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a method of preparing an InSb thin film, which can form an InSb thin film having high mobility on a surface of the aforementioned general substrate.
The method according to the present invention comprises a step of physically sticking InSb powder onto a major surface of a substrate, and a step of depositing an InSb thin film on the major surface of the substrate.
According to the inventive method, InSb powder is first physically stuck onto a major surface of a substrate, and an InSb thin film is then deposited on the major surface of the substrate which is provided with the physically stuck InSb powder. The inventors have found that an InSb thin film having high mobility which is similar to that provided on a mica substrate is formed according to the present invention. It is conceivable that the InSb thin film which is formed on the major surface of the substrate is improved in crystallinity when InSb powder is physically stuck onto the major surface according to the present invention.
The substrate employed in the present invention is not restricted in particular, but generally prepared from an insulating substrate, such as an Si substrate having an SiO 2 film, an Si substrate having a film of silicon nitrides, an Si substrate having an Al 2 O 3 film, a glass substrate, a ferrite substrate, an Si substrate or a GaAs substrate.
According to the present invention, it is possible to form an InSb thin film, having high mobility which is equivalent to that provided on a mica substrate, also on such a general substrate. Therefore, no indirect working such as transfer is required for forming an element such as a Hall element or a magnetic resistive element. Further, any working method can be employed since it is possible to directly form an InSb thin film on a final substrate, whereby pattern accuracy of the as-formed element is improved and the range of its application is widened in response. For example, it is possible to form an InSb thin film on an Si substrate or a thin film which is formed on an Si substrate, whereby a monolithic sensor IC can be easily manufactured.
The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates relation between an evaporation time and a substrate temperature in Example of the present invention; and
FIG. 2 illustrates relation between an evaporation time and respective evaporation rates for In and Sb in Example of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
First Example
InSb polycrystalline powder of 10 μm in mean particle diameter, which is generally employed as an evaporation source or the like, was placed on a glass substrate. Thereafter gaseous nitrogen was blown to remove an excess part of the InSb powder from the glass substrate. Thus obtained was a glass substrate, which was provided with the InSb powder stuck onto its surface. While the step of placing the InSb powder on the substrate and that of removing the excess part of the InSb powder from the substrate by blowing gaseous nitrogen were carried out once in this Example, each step may be repeated a plurality of times at need.
Then, an InSb thin film was formed on the surface of the glass substrate, which was provided with the as-stuck InSb powder, by vacuum evaporation. In such formation of the thin film, the degree of vacuum was set at 1×10 -4 Pa. The substrate temperature was successively increased stepwise from 400° C. to 500° C., as shown in FIG. 1. As to the evaporation rates, In and Sb were simultaneously evaporated. The evaporation rate for In was successively increased stepwise from 5.0 Å/sec. to 8.0 Å/sec. while that for Sb was set at a constant value of 6.0 Å/sec., as shown in FIG. 2.
Thus, an InSb thin film of 2.0 μm in thickness was formed on the glass substrate. This InSb thin film was patterned into a Hall element pattern by photolithography. The as-formed pattern of the InSb thin film exhibited mobility of 51200 cm 2 /V·sec.
While the InSb powder was stuck onto a dry glass substrate by electrostatic force in, the aforementioned Example, the present invention is not restricted to such a sticking method. For example, a substrate may be previously coated with a liquid for forming an SiO 2 coatings, so that InSb powder is stuck onto this coating layer. Then, the liquid coating the substrate may be glassified by firing to fix the InSb powder to the surface of the substrate. An InSb thin film may be deposited on the substrate, onto which the InSb powder is stuck in the aforementioned manner.
Second Example
InSb polycrystalline powder was added into a solution such as ethanol, to prepare a suspension. Then, an Si(100) substrate having an SiO 2 film of 1 μm in thickness was dipped in this suspension, and subjected to application of ultrasonic waves for about 60 minutes in the suspension. Thereafter the substrate was taken out from the suspension, and subjected to ultrasonic cleaning in pure water for 20 minutes and then in a cleaning solution for 20 minutes, respectively. Then, the substrate was baked in a clean oven at 150° C. for about 60 minutes.
An InSb thin film was formed on the substrate, which was pretreated in the aforementioned manner, by molecular beam epitaxy (MBE). Thin film forming conditions were a degree of vacuum of 4.0×10 -7 Pa, a substrate temperature of 400° C., and an evaporation rate Sb/In in a flow velocity ratio of 1.4.
Thus, an InSb thin film of 1 μm in thickness was formed on the substrate. This InSb thin film was patterned into a Hall element pattern by photolithography. The as-obtained pattern of the InSb thin film exhibited mobility of 60500 cm 2 /V·sec.
While the InSb thin films were deposited by vacuum evaporation and MBE in the aforementioned Examples, the present invention is not restricted to these methods. The InSb thin film may alternatively be deposited by laser ablation, sputtering or the like, for example.
While InSb polycrystalline powder was employed in each of the aforementioned Examples, the InSb powder may alternatively be single-crystalline.
Although the present invention has been described and illustrated in detail, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation, the spirit and scope of the present invention being limited only by the terms of the appended claims. | Disclosed herein is a method of preparing an InSb thin film, which comprises a step of physically sticking InSb powder onto a major surface of a substrate, and a step of depositing an InSb thin film on the major surface of the substrate provided with the as-stuck InSb powder by a method such as vacuum evaporation. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of PPA Ser. No. 60/986,524 filed 2007 Nov. 8 by the present inventor.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The subject invention generally pertains to electronic power conversion circuits, and, more specifically, to high frequency, switched mode electronic power converters. The subject matter relates to new boost power converter circuit topologies having bipolar outputs used for ac to dc power conversion and to power converter topologies having bipolar inputs.
2. Description of Related Art
Bridgeless power factor correction (PFC) boost converters have been known for some time. With the recent establishment of high efficiency legal mandates for power supplies they have become more popular. An example of a prior art bridgeless PFC boost converter is illustrated in FIG. 1 . The FIG. 1 circuit does not employ a bridge rectifier, but rather uses the boost converter's switches and rectifiers to accomplish the rectification. The FIG. 1 circuit employs two boost converters that are activated on alternate half cycles of the line voltage source, one converter is activated for the positive half cycle and the other boost converter is activated for the negative half cycle. In FIG. 1 during the positive half cycle of V SOURCE (terminal L positive with respect to terminal N) a boost converter comprising switch SW 2 , diode D 2 , LIN, and CFILT is active. During the positive half cycle switch SW 1 remains in an on condition for the entire half cycle and diode D 1 remains in an off condition for the entire half cycle. During the negative half cycle of V SOURCE (terminal L negative with respect to terminal N) a boost converter comprising switch S W1 , diode D 1 , L IN , and C FILT is active. During the negative half cycle, switch S W2 remains in an on condition and diode D 2 remains in an off condition. The FIG. 1 circuit accomplishes higher efficiencies by comparison to more conventional boost PFC circuits, but there are some problems associated with the FIG. 1 circuit. To accomplish PFC a PFC controller needs to regulate line current, which requires an ability to sense line current. In FIG. 1 both terminals of the series network containing the line voltage source and boost inductor are modulated at high frequency. It would be much easier to sense line current if one of the terminals of the input network were connected to an ac ground. Perhaps a bigger problem is the problem of common mode (CM) noise inherent to the FIG. 1 circuit. FIG. 2( a ) illustrates the line voltage wave form which indicates the two regions of operation, i.e., positive half cycle (Region 1 ) and negative half cycle (Region 2 ). FIG. 2( a ) illustrates the voltage wave form of the OUT-terminal during the positive half cycle with respect to terminal N of the line voltage source V SOURCE . In a typical application terminal N will be connected to earth ground at the electrical service entrance to a building or installation. During the positive half cycle the OUT-terminal is connected through S W1 to terminal N of V SOURCE . During the negative half cycle the OUT-terminal is alternately connected and disconnected from terminal N of V SOURCE , which results in the voltage wave form of FIG. 2( c ) for the OUT-terminal during the negative half cycle (Region 2 ). A similar ac wave form (not shown) appears at the OUT+ terminal during the negative half cycle. Parasitic capacitances in the circuit, illustrated in FIG. 3 transfer some of the ac signal at the output terminals back to the line voltage source. The ac signals are CM signals and can potentially result in an electromagnetic compliance (EMC) failure. FIG. 4 illustrates a post converter circuit that might be used with the FIG. 1 circuit in a typical application. For many consumer products sold throughout the world the PFC boost rectifier must accommodate ac line voltages ranging from 85 to 265 volts and the boost rectifier would typically have an output dc voltage of about 380 to 400 volts. A typical universal input circuit might use 500 volt rated mosfet switches. The load coupling network illustrated in FIG. 4 might typically contain an LC filter and a load and may or may not also contain a transformer for galvanic isolation plus a rectifier circuit. What is needed is a bridgeless boost circuit that does not have the current sensing problems and CM noise problems of the prior art with similar efficiency advantages.
FIG. 16 illustrates a very simple bridgeless PFC boost converter that can achieve both simple current sensing using a sense resistor placed between the N terminal of V SOURCE and the ground terminal and low common mode noise. Low common mode noise results because both output filter capacitors have a connection to an ac ground and line neutral. Because of the connection of the output filter capacitors to line neutral there can be no high frequency voltage wave forms at the output filter capacitor terminals. FIG. 17 illustrates how the circuit can be implemented using mosfets for the switches. FIG. 18 illustrates a zero voltage switching implementation of the FIG. 16 circuit using a prior art zero voltage switching cell. The FIG. 16 circuit has one significant drawback. The boost converter of FIG. 16 both charges and discharges the output filter capacitors during normal operation. Most boost converters only charge the output filter capacitor. The output filter capacitor of most boost converters is discharged only by the load. The fact that the output filter capacitors are discharged by the FIG. 16 circuit significantly increases the current, power, and thermal stresses of the output filter capacitors. In the FIG. 16 circuit the C FILT− capacitor is discharged when the C FILT+ capacitor is charged in region 1 and the C FILT+ capacitor is discharged when the C FILT− capacitor is charged in region 2 . The net effect is the charging of both capacitors, but additional losses are incurred because of the discharge currents. The additional losses incurred because of discharging is greatest at the minimum ac line voltage which is the worst case condition for the boost converter. What is needed is a bridgeless boost converter having simple current sensing, low CM noise, and no output filter capacitor discharging into the boost converter.
For a unipolar output boost converter a common downstream post converter is illustrated in FIG. 4 . For the FIG. 16 circuit the FIG. 4 circuit could be used as a downstream (load side) post converter, but the input voltage to the FIG. 4 circuit, when used with a FIG. 16 boost pre-regulator, is twice the voltage that would typically appear at the output of a typical unipolar output boost pre-regulator. To use the FIG. 4 circuit with a bipolar output boost pre-regulator requires switches with twice the voltage rating of a unipolar boost pre-regulator. For a universal input boost pre-regulator 1000 volt switches would be required. 1000 volt switches are readily commercially available, but 1000 volts represents the high end of what is available in power mosfets and the available choices are reduced considerably in comparison to the choices at 800 volts and below. An equivalent 1000 volt mosfet can be formed by stacking two 500 volt mosfets, but with 500 volt mosfets 8 transistors are required to implement the FIG. 4 circuit. What is needed are solutions for downstream (load side) post converters for bipolar output boost converters that rely on four or fewer 500 volt mosfets with capability and performance equivalent to the FIG. 4 post converter.
OBJECTS AND ADVANTAGES
An object of the subject invention is to reveal new ac input boost converters having higher efficiency than conventional power factor correction boost converters.
Another object of the subject invention is to reveal new ac input boost converters which can employ a simple current sensing mechanism.
Another object of the subject invention is to reveal new ac input boost converters having good CM noise performance.
Another object of the subject invention is to reveal new ac input boost converters that can be used with zero voltage switching networks to accomplish higher conversion efficiency at higher switching frequencies.
Another object of the subject invention is to reveal new source switching networks that can operate from three terminal bipolar voltage sources.
Further objects and advantages of my invention will become apparent from a consideration of the drawings and ensuing description.
These and other objects of the invention are provided by novel boost circuit structures that eliminate or reduce CM noise coupling mechanisms, provide simple structures for sensing input current, and provide high efficiency at high switching frequencies.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention is illustrated by reference to the drawings.
FIG. 1 illustrates an ac input bridgeless boost converter according to the prior art.
FIG. 2( a ) illustrates a line voltage wave form divided into positive and negative current regions.
FIG. 2( b ) illustrates an output voltage wave form of the FIG. 1 circuit during a positive half cycle.
FIG. 2( c ) illustrates an output voltage wave form of the FIG. 1 circuit during a negative half cycle.
FIG. 3 illustrates the FIG. 1 circuit with CM noise coupling capacitances illustrated according to the prior art.
FIG. 4 illustrates a typical post converter circuit structure which can be used with an input boost pre-regulator circuit according to the prior art.
FIG. 5 illustrates an improved ac input bridgeless bipolar output boost converter according to the subject invention.
FIG. 6( a ) illustrates a line voltage wave form divided into positive and negative current regions.
FIG. 6( b ) illustrates a positive output voltage wave form of the FIG. 5 circuit during either a positive line voltage half cycle or a negative line voltage half cycle according to the subject invention.
FIG. 6( c ) illustrates a negative output voltage wave form of the FIG. 5 circuit during either a positive line voltage half cycle or a negative line voltage half cycle according to the subject invention.
FIG. 7 illustrates a source switching network structure which can be used with the FIG. 5 circuit.
FIG. 8( a ) illustrates how a mosfet is equivalent to a switch with unidirectional voltage blocking capability.
FIG. 8( b ) illustrates how two mosfets can be combined to form a switch with bi-directional voltage blocking capability.
FIG. 8( c ) illustrates how two mosfets can be combined to form a switch with bi-directional voltage blocking capability.
FIG. 9 illustrates a method to reduce gate drive switching losses in a pair of mosfets connected to achieve bi-directional voltage blocking capability.
FIG. 10 illustrates the FIG. 5 circuit employing semiconductor switches combined with the FIG. 7 circuit according to the subject invention.
FIG. 11 illustrates a source switching network that reduces the voltage applied to the load coupling network by a factor of two compared to the FIG. 7 source switching network.
FIG. 12 illustrates the FIG. 5 boost converter with mosfet switches and synchronous rectifiers according to the subject invention.
FIG. 13 illustrates an equivalent active circuit of the FIG. 12 circuit in region 1 according to the subject invention.
FIG. 14 illustrates an equivalent active circuit of the FIG. 12 circuit in region 2 according to the subject invention.
FIG. 15 illustrates the FIG. 12 circuit with a zero voltage switching (ZVS) cell according to the subject invention.
FIG. 16 illustrates an ac input bipolar output boost converter employing only two switches according to the prior art.
FIG. 17 illustrates the FIG. 16 circuit with the switches implemented using power mosfets according to the prior art.
FIG. 18 illustrates the FIG. 17 circuit with a ZVS cell according to the prior art.
FIG. 19( a ) illustrates a timing wave form for the S A switch for the circuit of FIG. 7 operating with pulse width modulation.
FIG. 19( b ) illustrates a timing wave form for the S B switch for the circuit of FIG. 7 operating with pulse width modulation.
FIG. 19( c ) illustrates a timing wave form for the S C switch for the circuit of FIG. 7 operating with pulse width modulation.
FIG. 19( d ) illustrates a timing wave form for the S D switch for the circuit of FIG. 7 operating with pulse width modulation.
FIG. 20( a ) illustrates a timing wave form for the S A switch for the circuit of FIG. 7 operating with phase shift modulation.
FIG. 20( b ) illustrates a timing wave form for the S B switch for the circuit of FIG. 7 operating with phase shift modulation.
FIG. 20( c ) illustrates a timing wave form for the S C switch for the circuit of FIG. 7 operating with phase shift modulation.
FIG. 20( d ) illustrates a timing wave form for the S D switch for the circuit of FIG. 7 operating with phase shift modulation.
FIG. 21( a ) illustrates a load coupling network for an inverter or amplifier.
FIG. 21( b ) illustrates a load coupling network for an isolated full wave forward converter.
FIG. 21( c ) illustrates a load coupling network for an isolated full wave coupled inductor buck converter.
FIG. 22( a ) illustrates a timing wave form for the S A switch for the circuit of FIG. 11 operating with three state pulse width modulation.
FIG. 22( b ) illustrates a timing wave form for the S B switch for the circuit of FIG. 11 operating with three state pulse width modulation.
FIG. 22( c ) illustrates a timing wave form for the S C switch for the circuit of FIG. 11 operating with three state pulse width modulation.
FIG. 22( d ) illustrates a timing wave form for the S D switch for the circuit of FIG. 11 operating with three state pulse width modulation.
FIG. 23( a ) illustrates a timing wave form for the S A switch for the circuit of FIG. 11 operating with two state pulse width modulation.
FIG. 23( b ) illustrates a timing wave form for the S B switch for the circuit of FIG. 11 operating with two state pulse width modulation.
FIG. 23( c ) illustrates a timing wave form for the S C switch for the circuit of FIG. 11 operating with two state pulse width modulation.
FIG. 23( d ) illustrates a timing wave form for the S D switch for the circuit of FIG. 11 operating with two state pulse width modulation.
SUMMARY
The subject invention reveals a new bridgeless ac input boost power converter circuit which eliminates common mode noise generating mechanisms of prior art bridgeless ac input boost power converters. The new circuit topologies also provide for simple input current sensing for power factor correction applications. The subject invention also reveals bridgeless ac input boost converters having zero voltage switching. Source switching networks that can be used with the bipolar voltage outputs of the new bridgeless ac input boost converters are revealed.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 5 illustrates an ac input bipolar output boost converter according to the subject invention. In FIG. 5 an input series network comprising an ac source of voltage, current, and power, V SOURCE , is connected to an input series inductance, L IN . L IN may be either a discrete series inductor or an inherent series inductance of the source of ac power. A first terminal of the series input network is connected to an output neutral terminal. A first main terminal of a switch S W is connected to a second terminal of the input series network and a second main terminal of switch S W is connected to a first terminal of the input series network. An anode terminal of a rectifier switch D 1 is connected to the second terminal of the input series network. A cathode terminal of D 1 is connected to a positive dc output terminal. An anode terminal of a rectifier switch D 2 is connected to a negative dc output terminal and a cathode terminal of rectifier switch D 2 is connected to the second terminal of the input series network and to the first main terminal of switch S W . A first terminal of a capacitor C FILT+ is connected to the positive dc output terminal and a second terminal of C FILT+ is connected to the output neutral terminal. A first terminal of a capacitor C FILT− is connected to the output neutral terminal and a second terminal of capacitor C FILT− is connected to the negative dc output terminal.
In operation during a first operating condition (Region 1 ) the current in the ac source is positive, the current in L IN is from left to right in FIG. 5 , and the average voltage of the second terminal of the input series network is positive with respect to the first terminal of the input series network. In a first switch state S W is on and both rectifier switches are off and current and magnetic stored energy in L IN are ramping up (increasing). When S W is turned off and rectifier switch D 1 is turned on a second switch state is initiated. During the second switch state current flows through D 1 to C FILT+ charging C FILT+ . During the second switch state D 1 is conducting current and magnetic stored energy in L IN are ramping down (decreasing). FIG. 13 illustrates the region 1 effective circuit with S W implemented using a mosfet.
In operation during a second operating condition (Region 2 ) the current in the ac source is negative, the current in L IN is from right to left in FIG. 5 , and the average voltage of the second terminal of the input series network is negative with respect to the first terminal of the input series network. In a first switch state S W is on and both rectifier switches are off and current and magnetic stored energy in L IN are ramping up (increasing). When S W is turned off and rectifier switch D 2 is turned on a second switch state is initiated. During the second switch state current flows through D 2 to C FILT− charging C FILT− . During the second switch state D 2 is conducting current and magnetic stored energy in L IN is ramping down (decreasing). FIG. 14 illustrates the region 2 effective circuit with S W implemented using a mosfet.
FIG. 6( a ) illustrates the voltage source wave form. FIG. 6( b ) illustrates the voltage wave form at the positive dc output terminal with respect to the neutral dc output terminal and the N (neutral) terminal of the ac voltage source and FIG. 6( c ) illustrates the voltage wave form at the negative dc output terminal with respect to the neutral dc output terminal and the N (neutral) terminal of the ac voltage source.
From FIGS. 6( b ) and 6 ( c ) it is clear that there is no high frequency switching component at the output terminals as there is in some of the prior art bridgeless boost circuits.
The FIG. 5 embodiment requires switch means S W with bi-directional current flow and bi-directional voltage blocking capabilities. FIG. 8( a ) illustrates a power mosfet and its equivalent switch, which has bi-directional current flow capability, but the single mosfet can block voltage in only one direction because of its inherent body diode. FIG. 8( b ) illustrates one method of combining two power mosfets so that the composite switch has both bi-directional current flow and bi-directional voltage blocking capabilities. A combination of two IGBTs or combinations of bipolar transistors and diodes can also accomplish switches with bi-directional current flow and bi-directional voltage blocking capability. In FIG. 8( b ) the two mosfets are series connected, but oppositely oriented with source terminals connected. FIG. 8( c ) illustrates another method of combining two power mosfets so that the composite switch has both bi-directional current flow and bi-directional voltage blocking capabilities. In FIG. 8( c ) the two mosfets are series connected, but oppositely oriented with drain terminals connected. FIG. 10 illustrates the FIG. 5 circuit with the S W switch implemented using two series connected mosfets having a common source connection and with a downstream post regulator using the source switching network illustrated in FIG. 7 . It is possible to operate the FIG. 10 circuit with a single common gate source control signal for both boost mosfets. M 1 and M 2 are the boost mosfets. In order to reduce gate drive switching losses one boost mosfet can be modulated while the other boost mosfet remains fully enhanced for a half cycle of the line voltage source. The conditions for which the boost mosfets can be independently controlled is illustrated in FIG. 9 . FIG. 12 illustrates another embodiment similar to the FIG. 10 embodiment, but having mosfets used as synchronous rectifiers rather than rectifier diodes. FIG. 10 also contains a small value current sense resistor, R SENSE , in series with the N (neutral) terminal of the line voltage source for simple and direct current sensing. FIG. 15 illustrates a circuit similar to the FIG. 12 circuit but with the addition of a second bi-directional composite switch, an auxiliary capacitor, and an auxiliary inductor for accomplishing zero voltage switching. The zero voltage switching operation of the switching cell contained within the FIG. 15 circuit is described in a prior art patent, U.S. Pat. No. 6,411,153 for uni-directional applications. With a bi-directional composite switch, as indicated in FIG. 15 , the zero voltage switching cell described in the cited patent is applicable to the subject invention.
The ac input bridgeless boost converter of the subject invention has the property of bipolar output voltages. A conventional downstream post regulator that can be used with the ac input bridgeless boost converter of the subject invention is illustrated in FIG. 4 . In the FIG. 4 circuit no connection to the neutral output terminal is required. With a power factor correction boost converter with universal line range input, i.e., 85 to 265 volts ac, the output voltages of the boost converter of the subject invention will be approximately +400 and −400 volts dc. The switches of the FIG. 4 circuit used for a post regulator with the bipolar boost converter must have voltage breakdown ratings in excess of 800 volts. For a conventional unidirectional output boost pre-regulator the output voltage is 400 volts dc and 500 volt transistors would likely be employed in a downstream post regulator having the structure of FIG. 4 . For the FIG. 4 source switching network used with the bi-directional boost converter 1000 volt transistors would be the preferred choice.
FIG. 7 illustrates a source switching network which can be used with a bipolar output boost pre-regulator. For a boost converter pre-regulator that generates positive and negative 400 volts the FIG. 7 source switching network would use 500 volt rated mosfets. Switch timing diagrams are illustrated in FIG. 19 , FIG. 20 , and FIG. 23 which are applicable to both the FIG. 7 source switching network and the FIG. 4 source switching network. The switch timing of FIG. 19 is applicable to a pulse width modulated (PWM) control equivalent to a PWM full wave bridge circuit. The voltages and currents of the switches in the FIG. 7 circuits are equivalent to the voltages and currents in the corresponding switches of the FIG. 4 circuit for the same load network with bipolar 400 volt boost outputs applied to the FIG. 7 circuit and unipolar 400 volt boost output applied to the FIG. 4 circuit. FIG. 20 illustrates switch timing for a phase shift modulated application for the switches of the FIG. 7 and FIG. 4 source switching networks. FIG. 23 illustrates a two state switch timing configuration which, in general, provides asymmetrical modulation for a average non-zero dc voltage to the load coupling network. With the FIG. 23 switch timing configuration the capacitor C FLOAT in FIG. 7 is obviated. The voltage applied to C FLOAT is equal to the supply voltage. C FLOAT provides a path for current flow when the voltage applied to the load coupling network is zero or nearly zero. In practice C FLOAT will be much smaller than C FILT+ or C FILT− . C FILT+ and C FILT− need to have relatively low impedance at the frequency of the ac input source voltage and C FLOAT needs to have relatively low impedance at the switching frequency of the source switching network. A typical input source frequency is 60 hertz and a typical switching frequency for the source switching network might be 100 kilohertz. FIG. 11 illustrates another source switching network for use with a bi-directional output boost pre-regulator. The voltages generated at the load coupling network in FIG. 11 are half the voltages generated by the FIG. 7 circuit. In a sense the FIG. 7 source switching network is a full bridge equivalent network for bipolar voltage sources and FIG. 11 is a half bridge equivalent network for bipolar voltage sources. Comparing the FIG. 11 source switching network to a half bridge the capacitor number and capacitor stresses are identical and the total switch stresses are also identical, but in the FIG. 11 circuit there are twice as many switches each carrying half the current of a switch in a half bridge. In FIG. 11 the load capacitors C LOAD1 and C LOAD2 have an applied voltage of one half of the supply voltage, so that for plus and minus 400 volt supply rails the capacitor voltages will be 200 volts. In FIG. 11 switches that are on simultaneously are effectively parallel connected, and in FIG. 7 switches that are on simultaneously are effectively series connected. Switch timing diagrams for the FIG. 11 circuit are illustrated in FIGS. 22 and 23 . The FIG. 22 switch timing diagram is applicable to load coupling networks that can tolerate an open source for part of the switching cycle. The FIG. 22 timing scheme employs three switch states, one of which is an open state. The FIG. 23 switch timing scheme employs two switch states, neither of which is open.
FIG. 21( a ) illustrates a non-isolated load network typical of an inverter or amplifier application. FIG. 21( a ) illustrates an isolated full wave forward converter load network. FIG. 21( c ) illustrates an isolated interleaved coupled inductor load network.
CONCLUSION, RAMIFICATIONS, AND SCOPE OF INVENTION
Thus the reader will see that the bridgeless bipolar output boost converter of the subject invention provides a compelling high efficiency approach to the problem of power factor correction without the problems of common mode noise and line current sensing inherent in prior art approaches. The reader will also see that the generation of bipolar outputs does not create a problem for post converters or load regulators. New load switching networks for bipolar voltage sources are revealed having identical switch complements with identical switch voltage and current stresses to more familiar and more common post regulator circuits used with unipolar output boost pre-regulators.
While my above description contains many specificities, these should not be construed as limitations on the scope of the invention, but rather, as exemplifications or preferred embodiments thereof. Many other variations are possible. For example, IGBTs, bipolar transistors, or junction FETs may be substituted for the mosfets illustrated as switch means in the subject application. The ac source may be a generator or other electromagnetic ac machine. Many other load coupling networks are possible. For example, for non-isolated loads a split and balanced inductor can be used to replace the single winding load inductor, for isolated applications a single transformer with dual secondary windings and a push pull rectifier rather than a full bridge rectifier may be used, or an inductor may be added in series with the primary transformer winding as a magnetic energy storage mechanism for zero voltage switching.
Accordingly, the scope of the invention should be determined not by the embodiments illustrated, but by the appended claims and their legal equivalents. | A new bipolar output boost converter for ac input applications is revealed. The new boost converter is bridgeless, i.e., it does not require use of a line frequency diode rectifier which improves the efficiency of the converter significantly. The new bipolar boost converter does not include the common mode noise generating mechanisms of prior art ac input bridgeless boost rectifier circuits, thereby easing electromagnetic compatibility problems. Although the new converter requires two output filter capacitors, total capacitor stored energy is the same as other boost converters of the same power level so that capacitor volume and cost is not significantly adversely effected. Zero voltage switching cells which can be substituted for a switch to eliminate first order switching losses are also revealed. New three terminal bipolar input source switching networks having operating properties similar to conventional full bridge source switching networks are also revealed. | 7 |
DESCRIPTION
[0001] 1. Technical Field
[0002] The present invention relates to an instrument driving device, and more particularly, relates to an instrument driving device with a built-in stopper mechanism.
[0003] 2. Background Art
[0004] There has been known a conventional instrument driving device disclosed in Patent Literature 1. In such an instrument driving device, a rotor including a magnet, which serves as a driving source by multipolar magnetization, and at least one reduction gear, which engages with the rotor, are built in a case, and a needle pointer is mounted on a needle point shaft which is mounted to the reduction gear and protrudes outside the case. As a structure for determining a zero point position, the instrument driving device includes the case provided with a stopper and the reduction gear provided with a protrusion. In addition, when the needle pointer is returned to a zero point, the instrument driving device stops the stopper member and the protrusion in a state (a zero point position) in which the stopper member and the protrusion come into contact with each other. In this case, the rotor is retained so as not to move by attraction to a magnetic member, such as a stator which is not shown, by magnetism.
CITATION LIST
Patent Literature
[0005] [PTL 1] Japanese Unexamined Patent Application Publication No. 2001-327149 (particularly see FIG. 3 )
SUMMARY OF THE INVENTION
Problems to be Solved by the Invention
[0006] A problem that the invention is to solve will be described using schematic views of FIGS. 6 to 8 . In the conventional instrument driving device, when an external force acts on the needle pointer or a needle pointer shaft 101 by a vibration, an impact, or the like and the needle pointer shaft 101 is inclined about a lower end thereof by an angle θ 1 in an arrow a direction, a reduction gear 102 is also inclined and a protrusion 103 provided in the reduction gear 102 is also inclined. Consequently, the protrusion 103 is displaced by a displacement x in an arrow b direction so as to overlap with a stopper 201 .
[0007] The protrusion 103 tries to push the stopper 201 from the left to the right of FIG. 7 by the displacement x in the arrow b direction. However, since the stopper 201 is provided in the case and is immovable, the protrusion 103 rotates about the needle pointer shaft 101 from the right to the left of FIG. 8 by an angle θ 2 in an arrow c direction as a reaction.
[0008] The reduction gear 102 engages with the rotor. The rotation of the rotor is decelerated to be transmitted to the reduction gear 102 , whereas the rotation of the reduction gear 102 is accelerated to be transmitted to the rotor. Accordingly, the rotation of the reduction gear 102 by the angle θ 2 is accelerated to be transmitted to the rotor.
[0009] An angle of the rotor which rotates together with the rotation of the reduction gear 102 upsets the state in which the rotor is stably retained by the attraction to the stator, and the protrusion 103 is separated from the stopper 201 at a position coming into contact with the stopper 201 . That is, the state in which the rotor is stably retained by the attraction to the stator, for example, originally, the state in which the needle pointer indicates a “0” scale (not shown in the drawing) by the protrusion 103 coming into contact with the stopper 201 enters a failure state by receiving a vibration, an impact, or the like, and thus the protrusion 103 is separated from the stopper 201 and the needle pointer indicates a position different from the “0” scale (not shown in the drawing). Therefore, there was a problem that so-called a step-out state is reached.
[0010] The present invention has been made in view of the above-mentioned problem, and an object thereof is to provide an instrument driving device with which it is possible to suppress a step-out caused by a vibration, an impact, or the like.
Means for Solving the Problem
[0011] An instrument driving device of the present invention includes a rotating magnet, a driving gear having the same axis as the magnet, an output gear driven by the magnet, a needle pointer shaft having a needle pointer mounted thereon and rotatably supports the output gear, a transmission gear that transmits rotation of the driving gear to the output gear, and a case that accommodates the magnet, the driving gear, the output gear, the transmission gear, and a portion of the needle pointer shaft, wherein
the case is provided with a stopper and a bearing portion that rotatably supports the needle pointer shaft, the output gear is provided with a protrusion that comes into contact with the stopper, the bearing portion is provided with a contact point with which the needle pointer shaft comes into contact, and an end at the protrusion side of the stopper is provided at the same position as the contact point in an axial direction of the needle pointer shaft.
[0016] Furthermore, in the present invention, a contact portion having the contact point may have a sectional circular shape in an axial direction of the bearing portion.
[0017] Furthermore, in the present invention, a contact portion having the contact point may have a spherical surface shape.
[0018] Furthermore, in the present invention, an end of the needle pointer shaft may have a planar surface in a direction perpendicular to the axial direction of the needle pointer shaft.
Effect of the Invention
[0019] According to the above-mentioned present invention, it is possible to provide an instrument driving device with which it is possible to suppress a step-out caused by a vibration, an impact, or the like.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] [ FIG. 1 ] A top view illustrating an instrument driving device according to an embodiment of the present invention.
[0021] [ FIG. 2 ] A cross-sectional view taken along line A-A of FIG. 1 .
[0022] [ FIG. 3 ] A top view illustrating an instrument driving device from which an upper case is removed and of which a portion is cut, according to the embodiment.
[0023] [ FIG. 4 ] A schematic view illustrating the principal portions of an instrument driving device when viewed from the top, according to the embodiment.
[0024] [ FIG. 5 ] A front view illustrating an instrument device using an instrument driving device according to the embodiment.
[0025] [ FIG. 6 ] A schematic view illustrating the principal portions of a conventional instrument driving device when viewed from the side. [ FIG. 7 ] A schematic view illustrating the principal portions of a conventional instrument driving device when viewed from the top.
[0026] [ FIG. 8 ] A schematic view illustrating the principal portions of a conventional instrument driving device when viewed from the top.
MODES FOR CARRYING OUT THE INVENTION
[0027] An instrument driving device 1 of the present embodiment is a stepping motor which is a kind of electric motor, and is used for an instrument device M including a needle pointer 14 and rotates the needle pointer 14 .
[0028] The stepping motor 1 of the present embodiment includes a magnet 2 , a driving gear 3 which has the same axis as the magnet 2 , a transmission gear 4 which has a first gear 4 a engaging with the driving gear 3 and a second gear 4 b provided on the same axis as the first gear 4 a, an output gear 5 which engages with the second gear 4 b of the transmission gear 4 , two coils 9 which generate a rotating magnetic field to apply a rotational force to the magnet 2 , a first rotating shaft 10 which is a rotation center of the magnet 2 , a second rotating shaft 11 which is a rotation center of the transmission gear 4 , a needle pointer shaft 6 which is a rotation center of the output gear 5 , a retention magnet 18 , and a case 12 which accommodates the magnet 2 , the driving gear 3 , the transmission gear 4 , the output gear 5 , the needle pointer shaft 6 , the coils 9 , the first rotating shaft 10 , the second rotating shaft 11 , and the retention magnet 18 .
[0029] The magnet 2 is made of a synthetic resin including a magnetic material which is referred to as a so-called plastic magnet. The magnet 2 has a doughnut shape which has a through hole at a circular center thereof. The driving gear 3 and the first rotating shaft 10 pass through the through hole. It is sufficient if the magnet 2 includes one or more each of an N-pole and an S-pole. In the present embodiment, the magnet 2 includes four magnetic poles in total of two N-poles and two S-poles, and the magnetic poles are provided so as to be radially uniform about a rotation axis of the magnet 2 . Accordingly, the magnetic poles are multipolar-magnetized on an outer peripheral surface of the magnet 2 along a rotational direction thereof using the first rotating shaft 10 as a central shaft.
[0030] The driving gear 3 is made of a synthetic resin without magnetism. The driving gear 3 is provided on the same axis as the magnet 2 and rotates together with the rotation of the magnet 2 . In addition, the first rotating shaft 10 passes through the driving gear 3 .
[0031] The transmission gear 4 is made of a synthetic resin without magnetism, and is integrally provided with the first gear 4 a and the second gear 4 b. The first gear 4 a engages with the driving gear 3 . In addition, the second gear 4 b engages with the output gear 5 . In addition, the transmission gear 4 is provided with the second rotating shaft 11 which is a rotation center.
[0032] Similarly to the driving gear 3 and the transmission gear 4 , the output gear 5 is also made of a synthetic resin without magnetism, and engages with the second gear 4 b of the transmission gear 4 . The output gear 5 is provided with the needle pointer shaft 6 which is a rotation center.
[0033] In FIG. 2 , a protrusion 15 is integrally provided on a lower side surface of the output gear 5 . The protrusion 15 includes a contact portion 15 a which comes into contact with a stopper 16 provided in the case 12 to be described later. The protrusion 15 stops the rotation of the needle pointer shaft 6 at a predetermined position and determines a rotation range of the needle pointer shaft 6 , by coming into contact with the stopper 16 .
[0034] In the present embodiment, a speed reduction mechanism including the driving gear 3 , the transmission gear 4 , and the output gear 5 is provided, and decelerates the rotation of the magnet 2 to transmit the decelerated rotation of the magnet 2 to the output gear 5 .
[0035] The needle pointer shaft 6 is axially supported to be rotatable by the case 12 , and a portion of the needle pointer shaft 6 protrudes to the outside. Furthermore, an end 6 a of the needle pointer shaft 6 has a planar surface in a direction perpendicular to the axial direction of the needle pointer shaft 6 .
[0036] Each of the coils 9 is to wind a metal wire such as copper having conductivity around a bobbin 9 a made of a synthetic resin. The coil 9 is connected to a control unit (not shown) through terminals 9 b provided at the bobbin 9 a.
[0037] The bobbin 9 a is a cylinder formed with a through hole having a sectional rectangular shape. The coil 9 is arranged on a periphery of the magnet 2 , and a portion of a disk surface of the magnet 2 faces an inner peripheral surface of the through hole in the state in which a portion of the magnet 2 is penetrated into the through hole of the bobbin 9 a.
[0038] By respectively inputting driving wave patterns, which are output from the control unit, to the two coils 9 , the rotating magnetic field is generated at the magnet 2 , and the rotational force is applied to the magnet 2 . Consequently, the rotation of the magnet 2 is transmitted to the needle pointer shaft 6 to drive the needle pointer shaft 6 .
[0039] The case 12 is made of a synthetic resin without magnetism, and divided into upper and lower portions. The case 12 divided into the upper and lower portions is fixed by hooking a lock claw 12 a provided at each of the upper and lower portions of the case 12 .
[0040] The case 12 rotatably supports the first rotating shaft 10 , the second rotating shaft 11 , and the needle pointer shaft 6 . Particularly, in order to rotatably support the needle pointer shaft 6 , the case 12 includes an upper bearing portion 12 b indicative of the middle of the needle pointer shaft 6 and a lower bearing portion 12 c to rotatably support the end 6 a of the needle pointer shaft 6 .
[0041] The upper bearing portion 12 b is a through hole, and the lower bearing portion 12 c is a recessed concave portion. The bottom of the lower bearing portion 12 c comes into contact with the needle pointer shaft 6 , and includes a contact portion 12 e having a contact point 12 d which is a support point where the needle pointer shaft 6 is inclined.
[0042] The contact portion 12 e having the contact point 12 d has a sectional circular shape in the axial direction of the lower bearing portion 12 c. Furthermore, in the present embodiment, the contact portion 12 e having the contact point 12 d has a spherical surface shape. The case 12 is integrally provided with the stopper 16 which comes into contact with the protrusion 15 provided on the output gear 5 .
[0043] The stopper 16 is a protruding three-dimensional object, and includes a contact portion 16 a which comes into contact with the protrusion 15 . In the present embodiment, the contact portion 15 a of the protrusion 15 comes into contact with the contact portion 16 b of the stopper 16 .
[0044] An end 16 b at the protrusion 15 side of the stopper 16 , that is, a height of the stopper 16 is the same position as the contact point 12 d in the axial direction of the needle pointer shaft 6 , as indicated by the dotted line in FIG. 2 .
[0045] The retention magnet 18 is made of a synthetic resin including a magnetic material which is referred to as so-called a plastic magnet, and has a columnar shape. The retention magnet 18 is provided in the vicinity of an outer periphery of the magnet 2 . The retention magnet 18 retains a stationary state using a magnetic force when the magnet 2 is static. The instrument driving device 1 of the present embodiment includes the retention magnet 18 , as a substitute for the stator which, when the magnet 2 is static, suppresses the rotation of the magnet 2 to carry out a retention function and is made of a magnetic material, similarly to the conventional instrument driving device.
[0046] In the present embodiment, the retention magnet 18 includes one each of an N-pole and an S-pole. In the present embodiment, the S-pole side is arranged to be directed toward the magnet 2 side.
[0047] In the present embodiment, in the state in which the protrusion 15 of the output gear 5 comes into contact with the stopper 16 of the case 12 , a relation between the magnet 2 and the retention magnet 18 corresponds to the state in which the S-pole 51 of the magnet 2 is repelled against the S-pole of the retention magnet 18 and the N-pole N 2 of the magnet 2 is attracted to the S-pole of the retention magnet 18 . In such a state, a force rotating in an arrow d direction is applied to the magnet 2 . The force rotating in the arrow d direction which is applied to the magnet 2 is stably retained in the state in which a force in an arrow e direction is applied to the transmission gear 4 , a force in an arrow f direction is applied to the output gear 5 , and the protrusion 15 of the output gear 5 comes into contact with the stopper 16 .
[0048] According to the above configuration, the magnet 2 is stably retained in the stationary state by the magnetic force of the retention magnet 18 .
[0049] FIG. 5 shows that the stepping motor 1 is used for the instrument device M. The instrument device M of the present embodiment indicates a vehicle speed using the needle pointer 14 .
[0050] The needle pointer 14 is mounted on the needle pointer shaft 6 . The needle pointer 14 is provided at the back thereof with a display board 17 which includes an index portion 17 a such as a scale or a character indicated by the needle pointer 14 . The needle pointer 14 is stopped at a predetermined position, or a position indicative of “0” of the vehicle speed in the present embodiment, by the protrusion 15 and the stopper 16 provided in the stepping motor 1 .
[0051] The result of the above configuration is that even when an external force such as a vibration or an impact acts on the needle pointer 14 or the needle pointer shaft 6 and thus the needle pointer shaft 6 is inclined about the end 6 a of the needle pointer shaft 6 and the protrusion 15 provided on the output gear 5 is inclined, since the contact point 12 d provided in the bearing portion 12 c and the end 16 b at the protrusion 15 side of the stopper 16 are arranged at the same position relative to the axial direction of the needle pointer shaft 6 , there is no case where the displacement of the protrusion 15 , resulting from the inclination, will not overlap the stopper 16 , and as a consequence, it is possible to prevent the protrusion 15 from rotating around the needle pointer shaft 6 . Accordingly, it is possible to suppress the rotation of the needle pointer shaft 6 due to a vibration, an impact, or the like, so that it is possible to suppress the rotation of the magnet 2 connected by the transmission gear 4 and the like, resulting in the suppression of a state referred to as so-called a step-out in which the needle pointer 14 indicates a position different from a “0” scale.
INDUSTRIAL APPLICABILITY
[0052] The present invention is available for an instrument driving device including a reduction mechanism.
DESCRIPTION OF REFERENCE NUMERALS
[0053] 1 Instrument driving device (stepping motor)
[0054] 2 Magnet
[0055] 3 Driving gear
[0056] 4 Transmission gear
[0057] 5 Output gear
[0058] 6 Needle pointer shaft
[0059] 12 Case
[0060] 12 c Lower bearing portion
[0061] 12 d Contact point
[0062] 12 e Contact portion
[0063] 14 Needle pointer
[0064] 15 Protrusion
[0065] 15 a Contact portion
[0066] 16 Stopper
[0067] 16 a Contact portion
[0068] 16 b End
[0069] 18 Retention magnet
[0070] M Instrument device | Provided is an instrument driving device which is capable of suppressing loss of synchronism caused by vibration and impact etc. The driving device ( 1 ) comprises: a magnet ( 2 ) which rotates; a driving gear ( 3 ) which is coaxial with the magnet ( 2 ); an output gear ( 5 ) which is driven by the magnet ( 2 ); a needle pointer shaft ( 6 ) which has a needle pointer ( 14 ) mounted thereon and also rotatably supports the output gear ( 5 ); a transmission gear ( 4 ) which transmits rotation of the driving gear ( 3 ) to the output gear ( 5 ); and a case ( 12 ) which accommodates parts of the magnet ( 2 ), the driving gear ( 3 ), the output gear ( 5 ), the transmission gear ( 4 ), and the needle pointer shaft ( 6 ), wherein a stopper ( 16 ) and a bearing part ( 12 c ) which rotatably supports the needle pointer shaft ( 6 ) are provided in the case ( 12 ), a protrusion ( 15 ) which makes contact with the stopper ( 16 ) is formed in the output gear ( 5 ), a contact point ( 12 d ) with which the needle pointer shaft ( 6 ) makes contact is formed in the bearing part ( 12 c ), and the end section ( 16 b ) at the protrusion ( 15 ) side of the stopper ( 16 ) is in the same position as the contact point ( 12 d ) in the axial direction of the needle pointer shaft ( 6 ). | 8 |
BACKGROUND OF THE INVENTION
This application is a continuation-in-part of application Ser. No. 07/478,742 filed Feb. 12, 1990, now abandoned, which was a continuation of application Ser. No. 07/099,978 filed Sep. 23, 1987, now abandoned.
This invention relates to a method of supplying a culture medium into a culture vessel for cultivating culture cells and to a culture system for carrying out the method of supplying the culture medium.
Recently, culture systems have been earnestly investigated for the purpose of reproducing biological cells in artificial vessels. Such a culture system can produce an artificial environment for the biochemical reaction in a living body and makes it possible to produce substances, such as immunoglobulin, which are beneficial for human society, continuously in large quantities with a higher efficiency. Such substances have been produced by cultivating inoculation culture substances in living animal bodies such as mice and the like.
Jar fermentor, roller bottle, membrane cultivating methods and the like have been known. Culture systems for these methods have been studied to improve them.
FIG. 1 is a block diagram schematically illustrating one exemplary arrangement of a prior art culture system using membranes.
This culture system includes a culture vessel (for example, a hollow fiber filter) using the membranes and a culture medium tank from which a predetermined culture medium is supplied into the culture vessel in which required cells are cultivated.
In FIG. 1, the hollow fiber filter in culture vessel 11 mainly consists of a flow passage 11a for passing the culture medium supplied from the culture medium tank 12, and culture chambers 11b in which the cells are cultivated. Moreover, the flow passages 11a and the culture chambers 11b are partitioned by the membranes capable of cutting off predetermined molecular weights. Such partitions 11c serve to prevent cells cultivated in the culture chambers 11b from entering the flow passage 11a but permit the culture medium flowing in the flow passage 11a to be supplied into the culture chambers 11b and waste matters to be removed from the culture chambers 11b into the flow passage 11a.
Moreover, the culture medium stored in the culture medium tank 12 has been adjusted to have predetermined values of pH (hydrogen ion concentration), DO (dissolved oxygen concentration) and the like. Moreover, culture systems have been known, whose culture medium tanks include means for automatically adjusting pH, DO and other parameters.
A driving source 14 serves to supply the culture medium from the culture medium tank 12 into the culture vessel 11. Therefore, the culture medium enters one side of the flow passage 11a of the culture vessel 11 and leaves the other side of the culture vessel 11. As the driving source, peristaltic pumps, bellow pumps or magnetic pumps have been used.
In using a peristaltic pump as the driving source 14, sliding means scrapes outer surfaces of a silicon tube and the like of the pump to drive a culture medium in the silicon tube for supplying the culture medium into a culture vessel 11.
In using a bellows pump as the driving source 14, a culture medium stored in a bellows is fed from the bellows by its extension and contraction for supplying the culture medium into a culture vessel 11.
In using a magnetic pump as the driving source 14, a magnetic rotor provided in the pump is rotated by a magnetic force from the outside of the pump to drive a culture medium by the rotating force of the magnetic rotor for supplying the culture medium into a culture vessel 11.
When a peristaltic pump is used as the driving source, however, the sliding means which drives the culture medium often damages the tube when it is in use for a long period of time. As a result, the culture medium is not supplied into the culture vessel but flows away to places other than the culture vessel. Alternatively, the culture chambers are contaminated when the tube is damaged.
In order to avoid such problems, it is required to displace the sliding means to new positions periodically as maintenance.
Moreover, as the sliding means scrapes the tube, worn tube material is mixed into the culture medium. Therefore, it is required to filter the culture medium mixed with the worn tube material.
In using a peristaltic pump, pulsations occur in the culture medium being fed into the culture vessel resulting from the constructional characteristics of the peristaltic pump, so that the supply of the culture medium into the culture vessel is disturbed.
In using a bellows pump or a magnetic pump, particular maintenance and operation of the pump are needed although the disadvantages in the peristaltic pump are mitigated.
In hitherto used culture systems, particularly those using ultrafiltration membranes, the direction of flow of the culture medium in the flow passage in the culture vessel is fixed. Therefore, when anchored cells are used for cultivation, the cells anchored to the culture chamber on a side upstream of the flow of the medium in the chamber contact the culture medium which has been adjusted in pH values or the like, with the result that the cells on a side downstream of the flow tend to include waste matters produced by metabolism of the cells anchored on the side upstream of the flow. On the other hand, suspension cells are likely to be carried onto the side downstream of the flow by a driving action of the flow. Accordingly, a locally uneven cultivating environment is produced so that cultivating density of cultivated substances becomes uneven.
SUMMARY OF THE INVENTION
It is a primary object of the present invention to provide a method of supplying a culture medium into a culture vessel which eliminates all the disadvantages of the prior art as above described and is able to supply the culture medium stably with constant flow amounts for a long period of time.
It is another object of the invention to provide a culture system which is able to carry out the method described above and which has a construction eliminating damage of parts.
In order to achieve the primary object of the invention, in the method of supplying a culture medium into a culture vessel according to the invention, the culture medium is fed into a culture vessel under a pressure difference of a gas.
The term "being fed under pressure difference of a gas" used herein is intended to mean that a culture medium in a tank is subjected to a higher pressure to force the medium out of the tank into a system lower in pressure than that in the tank and/or a system is made lower in pressure than that in the tank including the culture medium to suck the medium from the tank into the system.
In carrying out the method of the invention, it is preferable to change directions of the culture medium fed into the culture vessel with time intervals. Namely, the culture medium is caused to flow into one side of the culture vessel and is drained from the other side of the culture vessel for a certain period of time, and then the culture medium is caused to flow into the other side of the vessel and is drained from the one side of the vessel, thereby changing the directions of the flow of the culture medium with time intervals at will.
The time for changing the directions of the flow of the culture medium is preferably determined depending upon kinds of cultivated substances, for example, tissue cells and the like forming skins and internal organs of animals.
In order to accomplish the second object of the invention, the culture system according to the invention comprises a culture vessel, a culture medium supply assembly for supplying a culture medium into the culture vessel, and a gas pressure supply assembly for supplying gas pressure for feeding the culture medium into the culture vessel with the aid of pressure differences of the gas.
The culture medium supply assembly comprises a culture medium adjusting tank having means for adjusting pH, DO values and the like, and first and second tanks for supplying, collecting and replenishing the culture medium. The culture medium supply assembly further comprises flow passages for connecting these tanks and switching-over means for selectively making these flow passages effective, according to requirements. Moreover, the culture medium supply assembly comprises flow passages for making connections between the culture medium adjusting tank and one end of the culture vessel. Flow passages, between the culture medium adjusting tank and the other end of the culture vessel. Flow passage switching-over means are provided for making effective either of the flow passages. Further, the culture medium supplying assembly comprises flow passages for connecting the culture vessel with first and second culture medium supply and collection tanks. Flow passage switching-over means are also provided for switching over the flow passages for collecting the culture medium from the culture vessel into one culture medium supply and collection tank when the flow passage between the other culture medium supply and collection tank and the culture medium adjusting tank is effective. The above flow passage switching-over means are preferably controlled by a control section described below.
Furthermore, the gas pressure supply assembly comprises a gas pressure producing section having first and second pressure chambers and a compressor for producing pressures in the first and second pressure chambers different from each other, such that, for example, the pressure in the first pressure chamber is higher than the pressure in the second pressure chamber. Moreover, the gas pressure supply section comprises a plurality of gas supply flow passages for feeding the gas from the respective pressure chambers into required locations of the culture system including the culture medium supply assembly, and switching-over means for switching over these gas flow passages.
According to the method of the invention, the culture medium is fed under a pressure difference into the culture vessel. Therefore, by keeping the pressure difference at a constant value, the flow rate of the culture medium can be maintained at a constant value corresponding to the pressure difference, thereby preventing pulsations in the culture medium. Further, by changing the pressure difference, the amount of the culture medium to be supplied can be controlled.
Moreover, by changing the kinds and components of the gas which is a pressure source for supplying the culture medium, the amount of gas dissolved in the culture medium can be easily controlled.
In the event that directions of the culture medium fed into the culture vessel are changed with time intervals, a direction of flow of the culture medium in the culture vessel is reversed. This change in flow direction stirs the culture medium in the culture chambers of the culture vessel and changes the cultivating environment so as to make uniform cultivating conditions in the culture chambers uniform.
According to the culture system of the invention, the culture medium is supplied under a pressure difference of gas pressures in the gas pressure supply assembly from the culture medium supply assembly into the culture vessel.
In more detail, when a passage between the first pressure chamber, the first culture medium supply and collection tank, the culture medium adjusting tank, the culture vessel, the second culture medium supply and collection tank and the second pressure chamber is effectively formed, the culture medium is fed under a pressure difference between the first and second pressure chambers from the first culture medium supply and collection tank through the culture medium adjusting tank and the culture vessel into the second culture medium supply and collection tank.
Moreover, the culture system according to the invention comprises flow passages for connecting the culture medium adjusting tank and one end of the culture vessel and for connecting the culture medium adjusting tank and the other end of the culture vessel. Also included in the invention is flow passage switching-over means for making effective either of these flow passages. Further flow passage switching-over means are provided for switching over the flow passages for connecting one end of the culture vessel opposite to the end being supplied with the culture medium to one of the culture medium supply and collection tanks, thereby effecting cultivation of the cells while changing the direction of flow of the culture medium in the culture vessel in the reverse direction with time intervals.
In order that the invention may be more clearly understood, preferred embodiments will be described, by way of example, with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram schematically illustrating an exemplary arrangement of a culture system of the prior art;
FIGS. 2A to 2E are block diagrams illustrating respective parts of a principal portion of one embodiment of the culture system according to the invention;
FIG. 3 is a block diagram illustrating a modification of a gas pressure supply section according to the invention;
FIGS. 4A and 4B are block diagrams illustrating respective parts of a principal portion of another embodiment of a culture system according to the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIGS. 2A and 2B are block diagrams illustrating respective principal parts of a culture system according to one embodiment of the invention. These block diagrams are drawn schematically o an extent such that the invention is understood, omitting sections for sterilization, cleaning and maintenance and the like for the sake of clarity. The arrangement of the respective components is not limited to that shown in FIGS. 2A and 2B. The Roman numerals I, II, and III, IV, V, VI shown in FIG. 2A are connected to the corresponding numerals I, II, III, IV, V, and VI shown in FIG. 2B.
Culture Vessel
A culture vessel 11 of this embodiment shown in FIG. 2B uses, for example, a publicly known hollow fiber. As explained with reference to FIG. 1, the hollow fiber filter 11 has a passage 11a for a culture medium, culture chambers 11b and partition walls 11c therebetween for cutting off material of a predetermined molecular weight. In the culture system of this embodiment, there is provided first temperature control means 13 constructed, for example, by a water jacket in order to maintain the hollow fiber filter at a desired environmental temperature.
The hollow fiber filter 11 further comprises an inlet 15 for supplying an inoculation culture substance and an outlet 17 for taking products out of the hollow fiber filter 11. A product receiving tank 91 is connected through a manually operable valve MV-1 to the outlet 17.
Culture Medium Supply Assembly
Reference numeral 21 denotes a culture medium supply assembly. The culture medium supply assembly 21 comprises a culture medium adjusting tank 23 for adjusting pH, DO and the like of the culture medium; first and second culture medium supply and collection tanks 25a and tank 25b, (also referred to hereinafter as "first tank 25a" and "second tank 25b", respectively. Culture medium flow passages are provided between the culture vessel 11, the culture medium. The present invention also comprises adjusting tank 23 and the first and second tanks 25a and 25b in predetermined relations, later described in detail. Switching-over means is provided for switching over these flow passages according to purposes (later described in detail). In order to detect upper and lower limit levels of the stored culture medium, the adjusting tank 23 includes level gages LI2, and the first and second tanks 25a and 25b include level gages LI1 and L13, respectively.
In this embodiment, the switching-over means consists of valves (later described in detail) provided in a predetermined manner in the plurality of flow passages in the culture medium supply section 21, and a control section 81 (see FIG. 2A) including means for closing and opening these valves.
In this embodiment, the valves are driven by gas pressure from a gas pressure supply section 61 according to instructions from the control section 81. However, the driving of the valves is not limited to this feature. They may be magnetically driven from the control section 81. The valves are designated by AV1-AV3 in FIG. 2B.
Connections of the culture medium flow passages between the above vessel and tanks will be explained hereinafter.
The first tank 25a and the culture medium adjusting tank 23 are connected through the flow passage 31, the valve AV1 and the flow passage 32. The second tank 25b and the culture medium adjusting tank 23 are connected through the flow passage 33, the valve AV4 and the flow passage 34.
The culture medium adjusting tank 23 and one end of the flow passage 11a of the culture vessel 11 are connected by the flow passage 35 having a flow meter 27, the flow passage 36 having a valve AV7 and the flow passage 37 having a valve AV9. Moreover, the culture medium adjusting tank 23 and the other end of the flow passage 11a of the culture vessel 11 are connected by the flow passage 35 having a flow meter 27, the flow passage 38 having a valve AV8 and the flow passage 39 having a valve AV10.
The flow passages 31 and 36 are connected by the valve AV3 and the flow passage 41, and the flow passages 33 and 36 are connected by the valve AV5 and the flow passage 42.
Moreover, the flow passages 31 and 38 are connected by the valve AV2 and the flow passage 43, while the flow passages 33 and 38 are connected by the valve AV6 and the flow passage 44.
A culture medium replenishing tank 51 separately prepared is connected through a sterilization filter F5, a valve AV11 and a flow passage 45 to the second tank 25b and is further connected through a sterilization filter F6, a valve AV12 and a flow passage 46 to the first tank 25a.
In this embodiment, the culture medium adjusting tank 23 is supplied through a flow passage 48 with oxygen, carbon dioxide or nitrogen and is further supplied through a flow passage 49 with an alkaline solution (7.5% NaHCO 3 solution in this embodiment) through a reservoir tank 50 as shown in FIG. 2B, thereby adjusting pH or DO in the tank 23 by the gas and chemical liquid. The tank 23 includes a sensor 29a for a pH meter and a sensor 29b for a dissolved oxygen meter as shown in FIG. 2B. It can be supposed that the introduction of the oxygen, carbon dioxide or nitrogen gas sometimes results in a change in the gas pressure in the culture medium adjusting tank 23, with the result that the surface level of the medium in the tank 23 is changed. In order to provide for such an extraordinary change in surface level, the culture medium adjusting tank 23 comprises a level gage LI4 and a valve V8 for venting. The culture medium adjusting tank 23 also serves as a buffer for restraining change in flow rate when switching over the flow passages.
Unused culture medium can be removed from the culture medium adjusting tank 23 through a flow passage 47, a valve AV13 and a sterilization filter F7.
In this embodiment, moreover, the culture medium supply assembly and the culture vessel 11 as above described are accommodated in a constant temperature bath 19 having second temperature control means.
Gas Pressure Supply Assembly
Reference numeral 61 denotes a gas pressure supply assembly. This gas pressure supply assembly 61 includes therein a gas pressure producing section 62 having first and second pressure chambers 63a and 63b and a compressor 65 for generating different gas pressures in the chambers 63a and 63b. An external gas, for example air, is introduced through a filter F1 and a magnetic three-way valve SV1 into the compressor 65 in which the gas is compressed and fed into the first pressure chamber 63a in which the compressed gas is stored. The remaining passage of the three-way valve SV1 is connected to the second pressure chamber 63b. Therefore, the pressure in the first pressure chamber is higher than that in the second pressure chamber.
Moreover, the first and second pressure chambers 63a and 63b are provided with pressure gauges PSI1 and PS12, each having pressure switches, and adapted to be connected by a primary pressure regulating valve RV2. These pressure chambers can be set at predetermined pressures in order to supply gas pressures from these pressure chambers for feeding the culture medium under a pressure difference. When the pressure in the first pressure chamber 63a arrives at a predetermined value, the pressure in the chamber 63a is regulated by the primary pressure regulating valve RV2. If the pressure in the first pressure chamber 63a becomes lower than the predetermined value, the magnetic three-way valve SV1 is switched over onto the air introducing side (filter F1 side) to replenish the air in the pressure chamber 63a until the pressure arrives at the predetermined value. When the pressure in the second pressure chamber 63b becomes lower than the predetermined value, the three-way valve SV1 is also switched over onto the air introducing side to introduce the external air once into the first pressure chamber 63a. Thereafter, excess air in the first pressure chamber 63a is fed through the primary pressure regulating valve RV2 into the second pressure chamber 63b.
Between the first pressure chamber 63a and the first tank 25a of the culture medium supply assembly 21, there is provided a gas flow passage 71 having a pressure regulating valve RV1, a magnetic valve V1, a magnetic three-way valve SV2 and a sterilization filter F2. Between the second pressure chamber 63b and the second tank 25b, there is provided a gas flow passage 72 having a valve V2, a three-way valve SV3 and a filter F3. Moreover, the three-way valve SV2 and the gas flow passage 72 are connected by a gas flow passage 73, and the three-way valve SV3 and the gas flow passage 71 are connected by a gas flow passage 74.
With this arrangement, one culture medium supply and collection tank 25a or 25b of the culture medium supply section is connected to the first pressure chamber 63a, while the other culture medium supply and collection tank 25b or 25a is connected to the second pressure chamber 63b so that a pressure difference is provided between the supply and collection tanks 25a and 25b to enable the culture medium to be fed under pressure difference into either of the tanks.
In such an arrangement of this embodiment, by switching over the three-way valves SV2 and SV3, the culture medium supply and collection tanks 25a and 25b can be changed to be connected to the second and first pressure chambers 63b and 63a, whereby gas flow passage switching-over means for switching over the gas flow passages is realized by the three-way valves SV2 and SV3.
The gas for feeding the culture medium under pressure has been explained as the air in the above embodiment. However, there is often a case that the amount of dissolved gas in the culture medium to be used for cultivating greatly affects the proliferation of cells or formation of products depending upon kinds of culture substances such as cells. For example, there are two cases, that a dissolved oxygen amount of a culture medium is more than equilibrium dissolved oxygen amount under the atmospheric pressure, and that the dissolved oxygen amount is less than the equilibrium dissolved oxygen amount. There are culture substances for which the former case is the better environment and others for which the latter is preferred.
When such culture substances are cultivated, it is preferable to determine the dissolved oxygen amount of a culture medium to be used which is appropriate for the culture substances.
In order to fulfill such a requirement, the method for supplying a culture medium uses a gas for feeding the medium under a pressure difference so that, for example, the equilibrium dissolved oxygen amount of the medium can be easily controlled by changing the gas to be used or components of the gas. For example, with a culture substance preferring a dissolved oxygen amount greater than the equilibrium dissolved oxygen amount at atmospheric pressure, air mixed with oxygen at a high concentration is supplied through the filter F1 into the gas pressure producing section shown in FIGS. 2A and 2B to fulfill the requirement. In contrast thereto, for a culture substance preferring a dissolved oxygen amount which is less than the equilibrium dissolved oxygen amount, for example, the air including oxygen at a low concentration obtained by diluting with nitrogen gas may be supplied.
Control Section
The culture system according to the invention comprises a control section for controlling the respective components above described. As the control section can be constructed according to the control technique of the prior art, it will be briefly explained hereinafter.
The control section 81 shown in FIG. 2A comprises, for example, a microprocessor 83, a memory device 85 for storing feeding directions of culture mediums, programs of culture conditions and the like, an input unit 87 for instructing mode selection and change of the feeding directions and culture conditions, input and output (I/O) ports 89 for reading pressure data of the first and second pressure chambers, flow rates of culture mediums, data of pH, DO and the like, data of amounts of culture mediums in the respective tanks and the like, and outputting instruction signal for modifying the pressure, pH, DO and the like and operating the respective values on the basis of these data, and a display unit 90 for displaying various messages.
Operation of the Culture System
The operation of the culture system will be explained hereinafter. The operation is effected in the following sequence (1)-(6). However, the present invention is of course not limited to this sequence. Moreover, the following numerical parameters are only by way of example, and could be modified according to kinds of inoculation culture substances:
(1) Sterilization;
(2) Supply of culture medium to the culture medium supply assembly;
(3) Adjusting the culture medium;
(4) Cells inoculation into the culture vessel;
(5) Supplying the culture medium to the culture vessel
(6) Sampling of Culture Substances and the Like During Period of Cultivating.
In this embodiment, moreover, hollow fiber filter cartridges having a molecular weight cut off at 30000 which are manufactured by Grace Co. in the United States under the trade name of "Vitafiber II", are used for the culture vessel.
(1) Sterilization
Before the cultivation of cells, the tanks 23, 25a and 25b and the flow passages inside the zone bounded by the sterilization filters F2, F3, F5, F6, F7, F9, F10 and F11 associated with the culture medium supply section 21 are sterilized by steam at any suitable temperature, for example, 120° C. for a predetermined period of time, for example, 30 minutes.
(2) Supply of Culture Medium to the Culture Medium Supply Assembly
After sterilization, the culture medium is supplied from the culture medium replenishing tank into the culture medium supply section. In this case, the culture medium is first replenished from the replenishing tank 51 into one of the supply and collection tanks, for example, the first tank 25a. Thereafter, the culture medium is fed through the culture medium adjusting tank 23 into the other supply and collection tank or the second tank 25b.
The valve V1 is then opened and the gas pressurized or adjusted by the pressure adjusting valve RV1 is supplied from the first pressure chamber 63a through the flow passage 75 and the sterilization filter F8 into the culture medium replenishing tank 51. On the other hand, the valve V2, the three-way valve SV3 and valves AV6, AV8 and AV1 are operated respectively to make effective the passage of the second pressure chamber 63b, the gas flow passage 72, the second tank 25b, the flow passage 33, valve AV6, the flow passages 44 and 38, the valve AV8, the flow passage 35, the flow meter 27, the culture medium adjusting tank 23, the flow passage 32, the valve AV1 and the flow passage 31, thereby forming a pressurized feeding system through the culture medium replenishing tank 51, the first and second tanks 25a and 25b, and the culture medium adjusting tank 23. After the formation of the feeding system, the valve AV12 is opened to supply the culture medium from the supply tank 51 through the flow passage 46 into the first tank 25a, and further the culture medium is fed under pressure difference from the first tank 25a through the adjusting tank 23 into the second tank 25b. The amount of the culture medium in the second tank 25b is monitored by means of the level gauge LI3. When the liquid surface of the supplied culture medium arrives at the lower limit level of the level gauge LI3, the valves AV1, AV6 and AV8 are closed upon detecting it. In order to feed the culture medium under a pressure difference from the supply tank 51 into the first tank 25a continuously, the three-way valve SV3 is switched over onto the side of the flow passage 74 to make effective the passage of the second pressure chamber 63b, the valve V2, the three-way valve SV3, the flow passages 74 and 71, the filter F2, the first tank 25a, the flow passage 46 and the valve AV12. The liquid surface of the culture medium in the first tank 25a is monitored by the level gauge L1. When the liquid surface arrives at the upper limit level of the gauge LI1, the valves AV12 and AV6 are closed upon detecting it.
Thereafter, the valve V1 and the three-way valve SV2 are actuated to supply the gas pressure in the first pressure chamber 63a adjusted to a predetermined pressure by the pressure adjusting valve RV1 into the first tank 25a through the gas flow passage 71. (The gas pressure adjusted to the predetermined pressure of the pressure adjusting valve RV1 is referred to sometimes as "first gas pressure".) Moreover, the valve V2 and the three-way valve SV3 are actuated to supply the gas pressure in the second pressure chamber 63b into the second tank 25b through the gas flow passage 72. (The gas pressure in the second pressure chamber to be supplied into the second tank 25b is referred to sometimes as "second gas pressure".) Further, the valves AV1, AV8 and AV6 are opened to feed the culture medium in the first tank 25a under pressure difference into the second tank 25b through the culture medium adjusting tank 23. The amount of the culture medium in the adjusting tank 23 is monitored by means of the level gauge LI2.
(3) Adjusting the Culture Medium
In the culture medium adjusting tank 23, respective parameters such as the pH, DO and the like of the medium are measured by means of respective sensors 29a and 29b. These measured results are fed into control section 81 and if values of these parameters are out of range of values suitable for culture cells, the culture medium is treated so as to bring the values into a predetermined range. If it is required to replenish oxygen for DO value from a result of measuring dissolved oxygen by the dissolved oxygen meter, oxygen is replenished through the flow passage 48 into the culture medium adjusting tank 23. On the other hand, if it is required to lower the dissolved oxygen amount, nitrogen is replenished through the flow passage 48 into adjusting tank 23. If it is required to raise the pH value from a result of measuring the pH value by the pH meter, an alkaline solution in the reservoir tank 50 is supplied through the flow passage 49 into the adjusting tank 23. If it is required to lower the pH value, CO 2 gas is supplied through the flow passage 48 into the adjusting tank 23. In case of lowering the pH value, moreover, an acid aqueous solution may be supplied instead of the CO 2 gas. Moreover, as the culture medium adjusting tank 23 is arranged in the second temperature control means (constant temperature bath) 19, the culture medium in the adjusting tank 23 is controlled substantially at a predetermined temperature. During cultivating operation, the temperature of the culture medium in the culture vessel is controlled with higher accuracy by means of the first temperature control means 13.
After the medium has been adjusted in the tank 23 for values such as pH, the medium is not immediately supplied into the culture vessel 11 (by keeping the valves AV9 and AV10 closed) and is circulated in the culture medium supply section 21 to bring it under a stable condition.
For the stabilizing operation of the culture medium, the medium in the culture medium adjusting tank 23 is first fed under a pressure difference into the second tank 25b through the flow passage 35, the valves AV8 and AV6 and the flow passage 33. The upper level of the culture medium in the second tank 25b is monitored by the level gauge LI3. After the medium in the tank 23 has been fed under a pressure difference into the second tank 25b, the valve AV6 is closed and the valve AV4 is opened. At this moment, the three-way valves SV2, SV3 and the like are opened to switch over the gas flow passages such that the second gas pressure is supplied from the second pressure chamber 63b into the first tank 25a and the first gas pressure is supplied from the first pressure chamber 63a into the second tank 25b. Moreover, the valve AV1 is closed, and the valves AV7 and AV3 are opened. Therefore, the culture medium is then fed under pressure difference from the second tank 25b into the medium adjusting tank 23 in which the parameters such as the pH are adjusted in the manner as above described. Then, the adjusted culture medium is fed under pressure difference into the first tank 25a through the flow passage 35, the valve AV7, the flow passage 36, the valve AV3 and the flow passage 31.
The culture medium is cyclically circulated between the medium adjusting tank 23 and the first and second tank 25a and 25b in the manner as above described to bring the temperature, pH and DO of the culture medium into predetermined values.
(4) Cell Inoculation Into the Culture Vessel
Then, for example, inoculation cells are poured into the culture chamber 11b through the inlet 15 of the hollow fiber 11 under an environment which has been treated so as not to contaminate the inoculation cells.
(5) Supplying the Culture Medium to the Culture Vessel
Then, the culture medium is supplied into the culture vessel. Such a supplying of the medium will be explained with reference to a case that in the supply section, for example, the first gas pressure is supplied into the first tank 25a and the second gas pressure is supplied into the second tank 25b, while the culture medium returning from the culture vessel 11 is restored or collected in the second tank 25b (the condition shown in FIG. 2B).
In this case, for the purpose of causing the culture medium to flow in two directions in the culture vessel, the culture medium in the first tank 25a is fed under a pressure difference through the adjusting tank 23 in the passage of the flow passage 35, the valve AV7, the flow passage 36, the valve AV9, the flow passage 37, the culture vessel 11, the flow passage 39, the valves AV10 and AV6, the flow passage 33 and the second tank 25b for a period of time during cell culture. For a next period of time, the culture medium in the first tank 25a is fed under pressure difference through the adjusting tank 23 in the passage of the flow passage 35, the valve AV8, the flow passage 38, the valve AV10, the flow passage 39, the culture vessel 11, the flow passage 37, the valve AV9, the flow passage 42, the valve AV5, the flow passage 33 and the second tank 25b. In this manner, the culture medium is caused to flow in two directions in which the medium enters one side of the culture vessel and leaves the other side of the vessel, and enters on the other side and leaves the one side of the vessel. The number of times of switching over the directions and the length of the period of the switching over are appropriately determined according to the culture cells. Directions in which the culture medium is fed into the culture vessel are changed with time intervals.
Moreover, when the culture medium supplied into the culture vessel is collected into the second tank 25b and its upper surface arrives at the upper limit level in the second tank 25b, the culture medium flow passages as above described are switched over such that the second gas is supplied into the first tank 25a, while the first gas is supplied into the second tank 25b to collect the culture medium returning from the culture vessel 11 into the first tank 25a. In this manner, the culture medium supply can be effected in the same manner as above described.
Furthermore, the culture medium can be fed under a pressure difference in one direction without switching over the flowing directions of the culture medium in the culture vessel.
(6) Sampling of Culture Substances and the Like During the Period of Cultivating
Sampling is carried out in a manner described herein for proliferation of the culture substance and estimation of product in this embodiment.
In a mode of supplying the culture medium into the culture vessel, the valve AV9 (or AV10) downstream of the flow of the culture medium in the culture vessel 11 is closed, and the valve MV1 between the outlet 17 of the culture vessel 11 and a product receiving tank 91 is opened. As a result, a pressure difference occurs between the culture medium adjusting tank 23 and the product receiving tank 91, so that the product in the culture chamber 11b is fed together with the culture medium under a pressure difference into the product receiving tank 91. The cells and products sampled in this manner are observed with microscopes for the cells and with reagents dependent upon the products.
Moreover, on the basis of such an observation of the culture medium, change in pH and consumed amount of DO, the time to exchange the culture medium is determined. The culture medium is replaced with a new one according to the obtained time. Further, part of the culture medium is sampled through the passage of the adjusting tank 23, the flow passage 47, the valve AV13 and the sterilization filter F7. Metabolites such as, for example, glucose, lactic acid and like in the sampled culture medium are estimated to find the consumed components and the change in waste matter in addition to the above observations. The results of the estimation may be used to determine the exchanging time of the culture medium.
Modification
It is evident that this application is not limited to the above embodiments.
For example, the gas pressure producing section 62 of the gas pressure supply assembly 61 has been shown constructed by the first and second pressure chambers 63a and 63b, the compressor 65, a plurality of valves and the pressure regulator in the above embodiment. However, the gas pressure producing section 62 may be constructed as shown in FIG. 3 in a simpler manner such that it includes a high pressure gas bomb 101 and a pressure regulator and a valve V2 on the lower pressure side which is directly connected to the atmospheric pressure without providing a low pressure chamber. With this arrangement, it is preferable to provide a filter having open mesh at an inlet for introducing the air to protect the sterilization filters F2 and F3. In a factory having an installation supplied with a high pressure gas, for example, air, nitrogen or the like, the gas pressure may be obtained from such an installation.
Moreover, the gas to be introduced into the gas supply assembly is not limited to air. Other suitable gases, for example, nitrogen, argon or the like or a mixture of these gases may be used.
In the above embodiment, the culture medium supply assembly which has been explained is provided with the culture medium adjusting tank 23. However, the culture medium adjusting tank may be removed from this arrangement, and instead thereof the pH and the like may be adjusted in the culture medium supply and collection tank or in the flow passages of the culture medium.
In this embodiment a culture system comprises a culture medium supply assembly 200 (FIGS. 2B and 2E) and a gas supply assembly 202 (FIGS. 2C and 2D) . The culture medium supply assembly comprises a culture medium supply and collection tank section 204 (FIG. 2E) , a culture medium flow passage switching-over section 206 (FIG. 2E) and a culture section 208 (FIG. 2E). The culture medium supply and collection tank section 204 has provided therein at least first and second tanks 210, 212 (FIG. 2E) for supplying and collecting the culture medium, respectively. Each of the tanks 210, 212; 25a, 25b has therein a gas phase 214 (FIG. 2E) and a culture medium phase 216 (FIG. 2E). And further, each of the tanks has provided thereto at least one gas port 218 (FIG. 2E) connected to the gas phase 214 and at least one culture medium port 220 (FIG. 2E) connected to the culture medium phase 216. The culture medium flow passage switching-over section 206 comprises first switching-over means 222 (FIG. 2E) for selecting a culture medium flow passage between the first and second tanks and the culture section. The culture section 208 comprises at least one culture vessel 11 (FIG. 2E). The culture vessel has provided thereto two culture medium ports 226 (FIG. 2E). One of the culture medium ports 226 is connected to the culture medium port 220 of the first tank 210 through the culture medium flow passage switching-over section 206 and the other to the culture medium port 220 of the second tank 212 through the switching-over section 206. The gas supply section 202 comprises a gas control section 228 (FIGS. 2C and 2D) and a gas flow passage switching-over section 230 (FIGS. 2C and 2D). The gas control section 228 has provided therein gas pressure regulating means 232 (FIGS. 2C and 2D), gas flow rate regulating means 234 (FIGS. 2C and 2D), gas component regulating means 236 (FIGS. 2C and 2D) and gas source switching-over means 238 (FIG. 2D). The gas control section 228 has also provided thereto at least two gas ports 240 (FIGS. 2C and 2E). The gas flow passage switching-over section 230 comprises second switching-over means 242 (FIGS. 2C and 2D) for selecting a gas flow passage 244 (FIGS. 2C and 2D) between the gas control section 228 and the first and second tanks 210, 212 (FIG. 2E). The gas flow passage switching-over section 230 is connected to the gas ports 240 of the gas control section 228 and to the gas port 218 of the first and second tanks 210, 212 of the culture medium supply section 200.
In accordance with one preferred example, using the gas pressure regulating means 232, a pressure difference is produced between the at least two gas ports 240 of the gas control section 228 so as to cause the transfer of the culture medium between the first and second tanks 210 and 212, while connecting one of the gas ports 240 of the gas control section 228 to the gas phase through the gas port 218 of the first tank 210 and the other gas port 240 to the gas phase through the gas port 218 of the second tank 212 by the use of the second switching-over means 242. Then the level change of the culture medium phase 216 in the first and second tanks 210 and 212 is caused by the transfer of the culture medium. In accordance with the level change, the gas flow passages to the gas ports 218 connected to the first and second tanks 210 and 212 are repeatedly switched-over each other by the second switching-over means 242 thereby for continuously feeding the culture medium to the culture vessel 11 of the culture section 208.
Further, in accordance with another preferred example, using the gas flow rate regulating means 234, a constant amount of the gas is supplied from at least one of the gas ports 240 of the gas control section 228 to the first or second tank 210 or 212 through the corresponding gas port 218 so as to cause the transfer of the culture medium between the first and second tanks 210 and 212. Then, the level changes of the culture medium phase 216 in the first and second tanks 210 and 212 caused by the transfer of the culture medium. In accordance with the level change, the gas flow passages to the gas ports 218 connected to the first and second tanks 210 and 212 are repeatedly switched-over each other by the second switching-over means 242 thereby for continuously feeding the culture medium to the culture vessel 11 of the culture section 208.
According to another preferred example, using the gas pressure regulating means 232, the pressure difference between at least two gas ports 240 of the gas control section 228 is changed to set the amount of the culture medium fed to the culture vessel 11 to a suitable one.
According to a further preferred example, using the gas flow rate regulating means 234, the gas flow rate is changed to set the amount of the culture medium fed to the culture vessel 11 to a suitable one.
According to another preferred example, using the gas pressure regulating means 232, gas pressure at the respective gas ports 240 of the gas control section 228 is regulated to control dissolved gas concentration of the culture medium fed to the culture vessel 11, while maintaining the constant pressure difference between the respective gas ports 240.
Further, in another preferred example, using the gas pressure regulating means 232, gas pressure of the gas phase 214 in one of the first and second tanks 210 and 212 is regulated to control dissolved gas concentration of the culture medium fed to the culture vessel 11, while maintaining the constant amount of the gas flow fed to the gas phase 214 in the other of the tanks 210 and 212.
Further, in accordance with another preferred example, using the gas component regulating means 236, gas component of a gas phase in one of the first and second tanks 210 and 212, the gas phase having a higher gas pressure than the other of the tanks 210 and 212, is regulated to control the dissolved gas concentration of the culture medium fed to the culture vessel 11.
According to another preferred example, using the gas source switching-over means 238, a sort of gas fed to a gas phase in one of the first and second tanks 210 and 212, the gas phase having a higher gas pressure than the other of the tanks 210 and 212, is switched-over to control the dissolved gas concentration of the culture medium fed to the culture vessel 11.
Further, according to another preferred example, the culture medium flow passage switching-over section 206 comprises two culture medium flow passages. One of the culture medium flow passages is connected at its one end to one of the culture medium ports 220 of the first tank 210 and its other end to one of the culture medium ports 226 of the culture vessel 11. The other of the culture medium flow passage is connected at its one end to one of the culture medium ports 220 of the second tank 212 and at its other end to the other of the culture medium ports 226 of the culture vessel 11.
In accordance with another preferred example, the culture medium flow passage switching-over section 206 has provided therein switching-over means 222 for feeding the culture medium in one direction to the culture vessel 11.
According to another preferred example, at least one filter means 246 for filtering out at least undesirable bacillus is connected between the culture medium supply assembly 200 and the gas supply assembly 202.
According to another preferred example, the culture system may further comprise a culture medium regulating section 250 (FIG. 2B) having provided therein a culture medium regulating tank 252 (FIG. 2B) and means for regulating the culture medium. The culture medium regulating tank 252 has inside thereof a gas phase 254 (FIG. 2B) and a culture medium phase 256 (FIG. 2B) and is provided with at least one gas port 258 (FIG. 2B) connected to the gas phase 254 and at least two culture medium ports 260 (FIG. 2B) connected to the culture medium phase 256. The gas port 258 is connected to the gas control section 228 and the culture medium port 260 to the culture medium flow passage switching-over section 206. The gas control section 228 comprises portions 217 (FIG. 2A) and 236 (FIG. 2B).
In accordance with another preferred embodiment, using the gas component regulating means 236, a gas component of the gas phase 254 in the culture medium regulating tank 252 is regulated to control the dissolved gas concentration of the culture medium fed to the culture section 208.
Regarding FIGS. 2A and 2B, the gas supply section 202 comprises the gas pressure supplying section 61 and the gas component regulating means 236.
Further, the culture system of the above embodiment has been shown provided with means for adjusting the pH, DO and temperature of the culture medium. However the culture system according to the invention may be provided with means for adjusting other parameters, for example, dissolved concentration of CO 2 and the like depending upon the material to be cultivated.
Moreover, the supply of the culture medium, the removal of products and the like may be effected in a suction mode with negative pressure. An embodiment for supplying the culture medium from the replenishing tank 51 into the first tank 25a in the suction mode will be briefly explained.
In this embodiment, the flow passage 75 between the sterilization filter F8 and the valve V6 is removed and one end of the filter F8 on the side opposite to the replenishing tank 51 is opened or exposed to the atmosphere.
The three-way valve SV1 is switched over onto the side of the second pressure chamber 63b and the compressor 65 is operated. Then the valve V5 is opened and the valve V1 is closed, and the air in the second pressure chamber 63b is forced out of the system through the valve V5 to bring the second pressure chamber 63b into negative pressure. The respective valves are then switched over so that the system of the second pressure chamber 63b, the valve V2, the three-way valve SV3, the flow passages 74 and 71, the filter F2, the first tank 25a and the flow passage 46 become effective. The valve AV12 is then opened so that the culture medium in the replenishing tank 51 is fed under pressure difference into the first tank 25a in the suction mode.
After starting the feeding under a pressure difference, the liquid level of the culture medium in the first tank 25a is monitored by the level gauge LI1 of the tank. When the level gauge LI1 detects the fact that the medium has arrived at its upper limit level, the valves AV12 and V2 are closed.
Then, the gas pressure producing assembly is brought into a condition similar to the culture medium supplying condition above described. Thereafter, the respective valves are switched over so that the flow system becomes effective. The flow system consists of the first pressure chamber 63a, the valves RV1, V1, and SV2, the flow passage 71, the filter F2, the first tank 25a, the flow passage 31, the valve AV1, the flow passage 32, the culture medium adjusting tank 23, the flow meter 27, the flow passage 35, the valve AV8, the flow passages 38 and 44, the valve AV6, the flow passage 33, the second tank 25b, the filter F3, the flow passage 72, the valves SV3 and V2 and the second pressure chamber 63b. Therefore, the culture medium in the first tank 25a is supplied through the adjusting tank 23 into the second tank 25b. The amount of the culture medium fed into the second tank 25b is monitored by the level gauge LI3. When the liquid surface has arrived at the lower limit level, the above flow system is completely closed so that the gas producing section is returned to the suction mode as above described, whereby the culture medium in the culture medium replenishing tank 51 is replenished into the first tank 25a in the same manner as above described. The amount of the culture medium in the first tank 25a is monitored by the level gauge LI1. When the liquid surface of the medium has arrived at the upper limit level, the valve AV12 is closed. The liquid surfaces of the medium replenished in the first tank 25a, the second tank 25b and the culture medium adjusting tank 23 as above described are shown in FIG. 2B. The replenishing of the culture medium can be effected in the suction mode in this manner.
The culture medium supply assembly and the gas pressure producing assembly according to the invention are not limited to the above embodiments and various modifications may be made depending upon supplying methods of the culture medium.
For example, the culture system may be constituted as shown in FIGS. 4A and 4B to provide for the following features, in that a culture medium is continuously introduced from outside of the culture system thereinto and continuously supplied into the culture vessel and further continuously drained out of the culture system, that a culture medium is continuously supplied into the culture vessel, while part of the culture medium is circulated in the culture system or drained out of the culture system, and that a culture medium is circulated in the culture system, while part of culture medium is drained out of the culture system or is replenished from outside of the culture system.
FIGS. 4A and 4B are schematic block diagrams of respective parts of a principal portion of a culture system capable of supplying and circulating the culture medium in this manner. In FIGS. 4A and 4B, like components are designated by the same reference numerals as those in FIGS. 2A and 2B, while components not essential for an understanding of the embodiment, for example, control section 81, detailed parts and the like are deleted.
In FIG. 4A, reference numeral 162 denotes a gas pressure producing assembly in the modified culture system. The gas pressure producing assembly 162 comprises a negative gauge pressure producing section 171 in addition to the component designated by 62 in FIG. 2A. The negative gauge pressure producing section 171 comprises a vacuum pump 173, a third pressure chamber 63c, a three-way valve SV4, magnetic valves V10 and V11, and a pressure indicator PSI 3 with a pressure switch. The vacuum pump 173 is controlled depending upon a set value of the pressure indicator PSI 3 to maintain the gas pressure in the third pressure chamber 63c at a desired negative gauge pressure. The third pressure chamber 63c is connected through a gas flow passage 110 having a magnetic valve V12 to the flow passage 72 (already explained) between the valves V2 and the three-way valve SV3.
The compressor, the vacuum pump and the valves of the gas pressure producing assembly 162 are operated so that pressures P1, P2 and P3 in the first, second and third pressure chambers 63a, 63b and 63c are maintained in a relation of P1>P2>atmospheric pressure>P3.
With the culture system including the gas pressure producing assembly 162, the three-way valves SV2 and SV3 are switched over to provide four conditions such that (1) the gas pressure P1 is supplied into the first tank 25a and the gas pressure P2 is supplied into the second tank 25b, (2) the pressure P2 is supplied into the first tank 25a and the pressure P1 is supplied into the second tank 25b, (3) the pressure P1 is supplied into the first tank 25a and the pressure P3 is supplied into the second tank 25b, and (4) the pressure P3 is supplied into the first tank 25a and the pressure P1 is supplied into the second tank 25b.
A modified culture medium supply assembly 121 is shown in FIG. 4B. The culture medium supply assembly 121 is fundamentally similar to the culture medium supply assembly 21 shown in FIG. 2B with the exception that arrangements of the culture medium flow passages and valves are different from those shown in FIG. 2B.
In this embodiment, the culture medium is supplied through a flow passage 111 shown in FIG. 4B into the first tank 25a or the second tank 25b. The culture medium in the first tank 25a or second tank 25b is further caused to flow through a culture medium adjusting tank 23, a flow meter 27, a flow passage 112, a flow direction switch-over bypass block 123 (referred to hereinafter as a "switch-over block"), and a flow passage 113.
The switch-over block 123 is constructed as follows. A loop-shaped flow passage is formed by a flow passage 36 having a valve AV7, a flow passage 38 having a valve AV8, a flow passage 41 having a valve AV3, and a flow passage 44 having a valve AV6. The flow passage 112 is connected to a connection between the flow passages 36 and 38, and the flow passage 113 is connected to a connection between the flow passages 41 and 44. Moreover, between the connection of the flow passages 36 and 41 and connection of the flow passages 38 and 44, there is provided a system consisting of a valve AV9, a culture vessel 11 and a valve AV10. Therefore, these valves are switched over according to objects so that in this switch-over block, the flow directions of the culture medium can be switched over and the culture medium can be circulated without supplying new culture medium into the culture vessel 11 in the similar manner explained with reference to FIG. 2B. These passages are for supplying the culture medium into the culture vessel 11 in order of the flow passage 112, the valves AV7 and AV9, the culture vessel 11, the valve AV10 and AV6, and the flow passage 113 or the flow passage 112, the valves AV8 and AV10, the culture vessel 11, the valves AV9 and AV3, and the flow passage 113. Moreover, the other passages are for bypassing the culture vessel 11 through the flow passage 112, the valves AV7 and AV3, and the flow passage 113 or flow passage 112, the valves AV8 and AV6, and the flow passage 113.
In this embodiment, the switch-over block is constructed as follows. The first and second flow passages 36 and 41 having the valves AV7 and AV3 are connected in series with each other. The third and fourth passages 38 and 44 having the valves AV8 and AV6 are connected in series with each other. The first and second flow passages 36 and 41 in series connected and the third and fourth flow passages 38 and 44 in series connected are connected in parallel in the flow passage consisting of the flow passages 112 and 113. The fifth flow passage having the valve AV9 is connected between one end of the culture vessel 11 and the connection between the first and second flow passages 36 and 41. The sixth flow passage having the valve AV10 is connected between the other end of the culture vessel and the connection between the third and second flow passages 38 and 44.
Examples of culture systems shown in FIGS. 4A and 4B will be concretely explained with regard to a mode of feeding culture mediums hereinafter.
EXAMPLE 1
In this case, a culture medium is continuously introduced into the culture system from the outside thereof, is continuously fed into the culture vessel 11, and is further continuously drained out of the culture system.
The respective valves are operated so that the gas pressure P1 is supplied to the first tank 25a and the gas pressure P3 is supplied to the second tank 25b. Then the passage of the valve AV11, the flow passage 111, the valve AV5, and the second tank 25b is made effective, so that a culture medium is fed under pressure difference in suction mode from the outside of the culture system through a culture medium supply replenishing line on a primary side of the valve AV11 into the second tank 25b. On the other hand, the passage of the first tank 25a, the valve AV1, the culture medium adjusting tank 23, the flow meter 27, the flow passage 112, the switch-over block 123, the flow passage 113 and the valve AV3 is made effective, so that the culture medium in the first tank 25a is drained under a pressure difference in positive pressure mode through the above passage out of the culture system.
Moreover, respective valves are opened so that the gas pressure P3 is supplied into the first tank 25a and the gas pressure P1 is supplied into the second tank 25b. Then the passage of the valve AV11, the flow passage 111, the valve AV2 and the first tank 25a is made effective, so that the culture medium is fed under pressure difference in suction mode from the outside of the culture system into the first tank 25a. On the other hand, the passage of the second tank 25b, the valve AV4, the culture medium adjusting tank 23, the flow meter 27, the flow passage 112, the switch-over block 123, the flow passage 113 and the valve AV13 is made effective, so that the culture medium in the second tank 25b is drained under pressure difference in positive pressure mode through the above passage including the switch-over block out of the culture system.
The two passages for supplying and draining the culture medium as above described are used by switching them over under the monitoring of the level gages LI1-LI3. The supply and drain of the culture medium according to Example 1 are carried out in this manner.
EXAMPLE 2
In this case, a culture medium introduced in the culture system is continuously circulated.
The introduction of the culture medium into the culture system is effected in the same manner as explained in Example 1. The explanation thereof will not be described in further detail.
The respective valves are operated so that the gas pressure P1 is supplied into the first tank 25a and the gas pressure P2 is supplied into the second tank 25b. Moreover, the passage of the first tank 25a, the valve AV1, the culture medium adjusting chamber 23, the flow meter 27, the flow passage 112, the switch-over block 123, the flow passage 113, the valve AV14, the flow passage ill, the valve AV5 and the second tank 25b is made effective, so that the culture medium in the first tank 25a is fed under a pressure difference in a positive mode into the second tank 25b through the above passage including the switch-over block 123.
The respective valves are operated so that the gas pressure P2 is supplied into the first tank 25a and the gas pressure P1 is supplied into the second tank 25b. Moreover, the passage of the second tank 25b, the valve AV4, the culture medium adjusting chamber 23, the flow meter 27, the flow passage 112, the switch-over block 123, the flow passage 113, the valve AV14, the flow passage 111, the valve AV2, and the first tank 25a is made effective, so that the culture medium in the second tank 25b is fed under a pressure difference in a positive mode into the first tank 25a through the above passage including the switch-over block 123.
The two culture medium supply and drain passages above described are used by switching over these passages under the monitoring by the level gauges LI1, LI3 to accomplish the circulation and feeding under pressure difference of the culture medium according to the method of Example 2. During the circulation in this manner, the valve AV13 is opened and closed in accordance with requirements, so that part of the circulating culture medium can be drained out of the culture system without stopping the supply of the culture medium into the culture vessel 11.
Further, by properly switching over the operations of Examples 1 and 2 above described, the culture medium can be replenished from the outside of the culture system into the culture system without stopping the supply of the culture medium to the culture vessel.
In this manner, continuous feeding of the medium is also possible according to the supply method of the culture medium according to the invention.
Although the gas pressure producing source has been explained as the compressor and vacuum pump, they are only by way of example, and other sources of gas under pressure such as pipe lines in a factory or compressed gas bombs could be used.
Furthermore, the culture medium supply assembly and the gas pressure supply assembly shown in the above embodiments and modifications could be variously changed without departing from the spirit and scope of the invention.
In carrying out the culture medium supply method or the culture system according to the invention, various culture cells may be used such as those anchoring on the hollow fiber or suspending in the culture chamber. Further, the supply of the culture medium to the culture vessel can be effected in a condition that the direction of flow of the culture medium in the culture system is fixed or periodically changed in opposite directions.
For example, when cells which tend to anchor to the hollow fibers or to be suspended in the chamber are cultivated by the culture medium supplied into the culture vessel in one direction or in two opposite directions, results shown in Table 1 will be obtained.
TABLE 1______________________________________ Direction of culture vessel medium, in culture One fixed direction Two directionsAnchored Cell density becomes higher Cell density is uniformcell in a zone upstream of the over all zone in the culture vessel. culture vessel.Suspended Cell density becomes higher Cell density is uniformcell in a zone downstream of over all zone in the the culture vessel. culture vessel.______________________________________
With the culture system according to the invention, moreover, various parameters for the operation can easily be controlled within very severe ranges as follows.
(a) Cultivating temperature--±0.1° C. with respect to a set temperature
(b) DO Value--±0.1 ppm dependent upon proliferation amount of cells.
(c) pH value-±0.1 with respect to a set value.
As can be seen from the above explanation, according to the culture medium, supply method and the culture system of the invention, the culture medium is fed under a pressure difference of gas for supplying the medium into the culture vessel.
As a result, the culture medium can be supplied into the culture vessel stably and smoothly without any surge or pulse for a long period of time.
Moreover, the culture system according to the invention is easy to maintain and durable in use because there is no mechanically slidable part. Further, there is no part with which the culture medium is mechanically in contact. As a result, maintenance can be carried out without permitting impurities to enter the culture medium, even if the gas pressure supply section fails.
In supplying the culture medium into the culture vessel, the direction of flow of the culture medium in the culture vessel is changed in an opposite direction according to the invention. Therefore, the cultivating environment can be made uniform throughout the culture vessel so that the cultivating yield rate is improved.
Furthermore, by changing kinds of gas for feeding the culture medium under a pressure difference or adjusting components of the gas depending upon kinds of the culture substances, the cultivating yield ratio is further improved.
According to the culture medium supply method and the culture system of the invention, the cultivation is carried out with an efficiency much higher than that of the prior art to produce cells and substances beneficial for human beings as immunoglobulin such as monoclonal antibody and the like.
It is further understood by those skilled in the art that the foregoing description is that of preferred embodiments of the disclosed methods and apparatus and that various changes and modifications may be made in the invention without departing from the spirit and scope thereof. | A culture system comprising at least first and second culture medium tanks including a gas phase, a culture medium phase, at least one gas phase port, and at least one culture medium port. At least one culture vessel. First switching-over members have a plurality of culture medium flow passages connected between the tanks and the culture vessels. The culture medium phase of the first tank flows through the passages to the culture medium phase of the second tank via the culture vessel. Switching-over of the culture medium flow passages causes the culture medium phase of the second tank to flow through the passages to the culture medium phase of the first tank via the culture vessel. Gas supply section comprises at least two pressure chambers and at least two gas ports connected to the pressure chambers. Second switching-over members have formed therein a plurality of gas flow passages allowing a gas to flow from the gas control section to the gas phase in the first and second tanks. Switching-over of the gas flow passages causes the gas flow to switch between the tanks. The gas control section includes gas pressure regulating members, gas flow rate regulating members and gas component regulating members. Gas source switching-over members are included. | 2 |
FIELD OF THE INVENTION
The present invention relates to crosslinkable compositions formed from functionalized polyolefin powders which can be used in the slush molding process or in the thermoforming of sheets or in injection molding over an insert and more particularly to compositions based on functionalized polyethylene.
PVC or polyolefin powders are used to obtain skins by the process of molding by the free flow of powder onto a hot mold (hereinafter called the slush molding process). Slush molding is used for the manufacture of skins for dashboards, door panels and consoles in the automobile field. The powder is brought into contact with the hot mold, for example by the free flow technique—the powder forms a skin by melting. These skins have a very soft feel and do not have residual stresses, which makes it possible, during the aging of the skin, to avoid the risk of the appearance of cracks caused by residual stresses relaxing.
BACKGROUND OF THE INVENTION
Automobile dashboards are very often made of polyurethane and covered with a PVC skin obtained by the slush molding process. It is becoming less possible to use PVC because of the risk of pollution caused by its combustion. It is therefore necessary to develop polyolefin skins. Polypropylene skins have already been disclosed in the prior art but these skins are not sufficiently resistant to the high temperatures which can be found in automobiles out in the sun and with closed windows—this resistance is measured by the hot creep.
Patent FR 2,721,319 discloses powder compositions for slush molding based on polypropylene and on ethylene-propylene rubber (EPR). The skins obtained do not have good creep resistance.
BRIEF DESCRIPTION OF THE INVENTION
Polyolefin powder compositions have now been found which can be used in slush molding, in the thermoforming of sheets or in injection molding over an insert and which are crosslinkable thus, abrasion resistance and good creep resistance are obtained. The present invention is thus a crosslinkable composition formed from functionalized polyolefin powder comprising:
a functionalized polyolefin (A) having an MFI of at least 20 (190° C./2.16 kg) containing an anhydride and/or epoxy functional group,
a product (B) having the role of crosslinking (A),
the composition having a particle size between 100 and 400 μm.
According to a first embodiment of the invention, (A) is chosen from copolymers of ethylene and an unsaturated carboxylic acid anhydride and (B) is chosen from copolymers of ethylene and an unsaturated epoxide.
According to a second embodiment of the invention, (A) is chosen from copolymers of ethylene and an unsaturated carboxylic acid anhydride and (B) is chosen from polyamines adsorbed on a zeolite.
According to a third embodiment of the invention, (A) is chosen from copolymers of ethylene and an unsaturated epoxide and (B) is chosen from polyamines adsorbed on a zeolite.
In the slush molding process, the composition of the invention is converted into a skin on contact with the mold. The crosslinking takes place at a higher temperature than the melting point of (A) when it is carried out while the skin is in the mold, such as, for example, in the three embodiments mentioned above. The crosslinking takes place at a temperature between room temperature and the softening point of (A) when this crosslinking is initiated subsequently by a process of moisture diffusion through the skin, such as, for example, in the second and third embodiment, if it is chosen to allow the moisture to drive the amine from the zeolite after formation of the skin.
DETAILED DESCRIPTION OF THE INVENTION
As regards the first embodiment, the copolymers (A) can be polyethylenes grafted with an unsaturated carboxylic acid anhydride or copolymers of ethylene and an unsaturated carboxylic acid anhydride which are obtained, for example, by radical polymerization.
The unsaturated carboxylic acid anhydride can be chosen, for example, from maleic, itaconic, citraconic, allylsuccinic, cyclohex-4-ene-1,2-dicarboxylic, 4-methyl-enecyclohex-4-ene-1,2-dicarboxylic, bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic and x-methylbicyclo[2.2.1]hept-5-ene-2,2-dicarboxylic anhydrides. Maleic anhydride is advantageously used. It would not be departing from the scope of the invention to replace all or part of the anhydride with an unsaturated carboxylic acid, such as, for example, (meth)acrylic acid.
As regards the polyethylenes onto which the unsaturated carboxylic acid anhydride is grafted, <<polyethylene>> is understood to mean homo- or copolymers.
Mention may be made, as comonomers, of:
α-olefins, advantageousely those having from 3 to 30 carbon atoms; mention may be made, as examples of α-olefins, of propylene, 1-butene, 1-pentene, 3-methyl-1-butene, 1-hexene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, 1-docosene, 1-tetracosene, 1-hexacosene, 1-octacosene and 1-triacontene; these α-olefins can be used alone or as a mixture of two or of more than two,
unsaturated carboxylic acid esters, such as, for example, alkyl(meth)acrylates, it being possible for the alkyls to have up to 24 carbon atoms; examples of alkyl acrylate or methacrylate are in particular methyl methacrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate or 2-ethylhexyl acrylate,
vinyl esters of saturated carboxylic acids, such as, for example, vinyl acetate or propionate,
dienes, such as, for example, 1,4-hexadiene,
the polyethylene can comprise several of the above comonomers.
The polyethylene, which can be a blend of several polymers, advantageously comprises at least 50% and preferably 75% (as moles) of ethylene and its density can be between 0.86 and 0.98 g/cm 3 . The MFI (viscosity index at 190° C./2.16 kg) is advantageously between 20 and 1000 g/10 min.
Mention may be made, as examples of polyethylenes, of:
low-density polyethylene (LDPE)
high-density polyethylene (HDPE)
linear low-density polyethylene (LLDPE)
very low-density polyethylene (VLDPE)
polyethylene obtained by metallocene catalysis, that is to say polymers obtained by copolymerization of ethylene and an α-olefin, such as propylene, butene, hexene or octene, in the presence of a single-site catalyst generally composed of a zirconium or titanium atom and of two cyclic alkyl molecules bonded to the metal. More specifically, the metallocene catalysts are usually composed of two cyclopentadiene rings bonded to the metal. These catalysts are frequently used with aluminoxanes as cocatalysts or activators, preferably methylaluminoxane (MAO). Hafnium can also be used as metal to which the cyclopentadiene is attached. Other metallocenes may include transition metals from Groups IVA, VA and VIA. Metals from the lanthanide series can also be used.
EPR (ethylene-propylene rubber) elastomers
EPDM (ethylene-propylene-diene) elastomers
blends of polyethylene with an EPR or an EPDM
ethylene/alkyl(meth)acrylate copolymers possibly containing up to 60% by weight of (meth)acrylate and preferably 2 to 40%.
The grafting is an operation known per se.
As regards the copolymers of ethylene and an unsaturated carboxylic acid anhydride, that is to say those in which the unsaturated carboxylic acid anhydride is not grafted, these are copolymers of ethylene, an unsaturated carboxylic acid anhydride and optionally another monomer which can be chosen from the comonomers that were mentioned above in the case of the ethylene copolymers intended to be grafted.
Use is advantageously made of ethylene/maleic anhydride and ethylene/alkyl(meth)acrylate/maleic anhydride copolymers. These copolymers comprise from 0.2 to 10% by weight of maleic anhydride and from 0 to 40% and preferably 5 to 40% by weight of alkyl(meth)acrylate. Their MFI is between 20 and 100 (190° C./2.16 kg). The alkyl(meth)acrylates have already been described above. The melting point is between 80 and 120° C.
The copolymer (A) is commercially available—it is produced by radical polymerization at a pressure which can be between 200 and 2500 bar. It is sold in the form of granules. It can be powdered by microgranulation, for example by using the underwater cutting technique of the company Gala (Virginia, USA) or by cryogenic grinding.
As regards (B), the copolymers of ethylene and of an unsaturated epoxide, these can be obtained by copolymerization of ethylene and of an unsaturated epoxide or by grafting the unsaturated epoxide onto the polyethylene. The grafting can be carried out in the solvent phase or onto the molten polyethylene in the presence of a peroxide. These grafting techniques are known per se. Regarding the copolymerization of ethylene and of an unsaturated epoxide, use may be made of the processes referred to as radical polymerization processes which usually operate at pressures between 200 and 2500 bar.
Mention may be made, as examples of unsaturated epoxides, of:
aliphatic glycidyl esters and ethers, such as allyl glycidyl ether, vinyl glycidyl ether, glycidyl maleate, glycidyl itaconate and glycidyl (meth)acrylate, and
alicyclic glycidyl esters and ethers, such as 2-cyclohexene-1-glycidyl ether, diglycidyl cyclohexene-4,5-carboxylate, glycidyl cyclohexene-4-carboxylate, glycidyl 5-norbornene-2-methyl-2-carboxylate and diglycidyl endo-cis-bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylate.
As regards the grafting, the copolymer is obtained from the grafting of a polyethylene homopolymer or copolymer as described for (A), except that an epoxide is grafted instead of an anhydride. As regards a copolymerization, this is also similar to (A) except that an epoxide is used. There may also be other comonomers, as in the case of (A).
The product (B) is advantageously an ethylene/alkyl(meth)acrylate/unsaturated epoxide copolymer. It may advantageously contain up to 40% by weight of alkyl(meth)acrylate, preferably 5 to 40%, and up to 10% by weight of unsaturated epoxide, preferably 0.1 to 8%.
The epoxide is advantageously glycidyl (meth)acrylate.
The alkyl(meth)acrylate is advantageously chosen from methyl (meth)acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate or 2-ethylhexyl acrylate. The amount of alkyl(meth)acrylate is advantageously from 20 to 35%. The MFI is advantageousely between 5 and 100 (in g/10 min at 190° C./2.16 kg) and the melting point is between 60 and 110° C. This copolymer can be obtained by radical polymerization of the monomers. The process for forming a powdering is carried out as for (A).
It would not be departing from the scope of the invention if the composition were to comprise several polymers (A) and/or several polymers (B). (This applies to all the embodiments).
As regards the proportions of (A) and (B), these are advantageously such that there are 0.1 to 1.5 (preferably 0.2 to 0.6) anhydride functional groups per epoxide functional group. It is advantageous to use a catalyst, that is to say a product capable of accelerating the reaction between the anhydride functional groups and the epoxide functional groups. This catalyst acts right from the melting of (A) and (B) which have to be similar. The proportion of catalyst is easily determined by a person skilled in the art, these reactions between anhydride and epoxide functional groups being known per se. The crosslinking is advantageously carried out by heating the mold at a temperature above the melting point of (A).
Mention may in particular be made, among the compounds capable of accelerating the reaction between the epoxy functional group present in (B) and the anhydride functional group present in (A), of:
tertiary amines, such as dimethyllaurylamine, dimethylstearylamine, N-butylmorpholine, N,N-dimethyl-cyclohexylamine, benzyldimethylamine, pyridine, 4-dimethyl-aminopyridine, 1-methylimidazole, tetramethylethyl-hydrazine, N,N′-dimethylpiperazine, N,N,N′,N′-tetramethyl-1,6-hexanediamine or a mixture of tertiary amines having from 16 to 18 carbon atoms and known under the name of dimethyltallowamine,
tertiary phosphines, such as triphenylphosphine,
zinc alkyl dithiocarbamates,
acids, such as polymers like LUCALEN (an ethylene/butyl acrylate/acrylic acid terpolymer),
magnesium salts such as mixtures containing 65% stearate salt and 35% palmitate salt.
As regards the second embodiment of the invention, the functionalized polyethylene (A) has already been described in the first embodiment. (B) is a polyamine adsorbed on a zeolite—under the effect of a temperature rise, the polyamine is desorbed and crosslinks (A). It is sufficient to choose a polyamine/zeolite pair such that the desorption takes place at least at the melting point of (A). The desorption is also brought about by water or moisture, which it is why it is recommended to add, to the zeolite charged with polyamine, another zeolite capable of adsorbing the moisture in order to prevent crosslinking during storage. This technique for crosslinking a polymer comprising carboxylic acid anhydride groups with zeolites which release polyamines under the effect of the temperature or of the moisture has been disclosed in U.S. Pat. No. 5,792,816, the contents of which are incorporated in the present application.
Mention may be made, as examples of polyamine, of: ethylenediamine, propanediamine, butanediamine, pentanediamine, hexanediamine, the isomers of the preceding amines, 1,2-diaminocyclohexane, 1,4-diaminocyclohexane, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, 3-[(N-aminoethyl)amino]propyltrialkoxysilane, triaminopropyltrialkoxysilane, piperazine, aminoethylpiperazine, diaminoethylpiperazine, xylylenediamine, isophoronediamine, 3,3′-dimethyl-4,4′-diaminocyclohexylmethane or 1,4-diaminobenzanilide. A portion of the polyamine can be replaced with polyols or aminoalcohols, such as, for example: ethylene glycol, propylene glycol, triethylene glycol, dipropylene glycol, butanediol, neopentyl glycol, cyclohexane-dimethanol, hydroquinone bishydroxyl ether, triethanolamine, methyldiethanolamine, tripropanolamine, N,N-di(2-hydroxyethyl)aniline, ethanolamine, diethanolamine, propanolamine, dipropanolamine and N-(hydroxyethyl)aniline. Regarding the zeolites, use is advantageously made of those having pore diameters between 0.3 and 1.5 nm and preferably of a zeolite chosen from the following four (the pore diameter is shown):
0.38 nm, designated as type 4A,
0.44 nm, designated as type 5A,
0.8 nm, designated as type 10X,
0.84 nm, designated as type 13X.
All these zeolites are available with a particle size of the order of 20 to 50 μm. The zeolite can, in addition to the polyamine, be charged with a catalyst for the reaction of the anhydride and the amine. Various examples of desorption temperatures are given below:
Desorption
temperature
Zeolite
Amine
(° C.)
4A
Ethylenediamine
175 +/− 5
4A
Ethanolamine
175 +/− 5
13X
Ethylenediamine
130 +/− 5
13X
Ethanolamine
125 +/− 5
13X
Diethylenetriamine
125 +/− 5
13X
Piperazine
120 +/− 5
Once the skin has formed, the crosslinking can be carried out by heating beyond the melting point of (A) or subsequently, the skin having been removed from the mold, by diffusion of the ambient moisture at a temperature of between room temperature and the softening point of (A).
As regards the third embodiment of the invention, this is of the same type as the second embodiment but the copolymer of ethylene and of a carboxylic acid anhydride is replaced with a copolymer of ethylene and of an epoxide. Such a copolymer has already been described as polymer (B) in the first embodiment. It is sufficient only for it to have an MFI of at least 20.
The grafting reaction is carried out in a single-screw or twin-screw extruder fed with polyolefins from a feed hopper, for example in the form of granules. The polyolefins are melted by heating in a first zone of the extruder and the reactants are introduced into the melt of the polyolefins in a second zone.
The radical initiators may be chosen from peroxides, peracids, peresters and peracetals. In general, they are used in an amount from 0.01% to 0.5% by mass with respect to the polyolefins to be grafted.
The compositions of the invention may also include anti-caking agents such as the silica AEROSIL R972, processing aids such as ethylene bis(stearamide), mold release agents, such as calcium stearate or magnesium stearate, and other ingredients, such as tackifying resins, such as the resin REGALITE R1115.
They may also include processing stabilizers such as IRGAFOS 168, DDPP, P-EPQ, TNPP, TPP, PS 800 and PS 802, antioxidants, such as IRGANOX 1010, 245, 259, 565, 1035, 1076, 1098, 1135, 1141, 1330, 1425, 3052, 3114, 5057 and M1024, mixtures of antioxidants and processing stabilizers, such as IRGANOX B225, and UV stabilizers, such as the TINUVIN and CHIMASSORB range from Ciba.
They may also include fillers and coloring pigments, such as carbon black and TiO 2 .
They may also include deodorizing agents, such as active carbon: for example 3S, CXV (CECA), undecylenic acid, ethyl undecylenate, calcium undecylenate, zinc undecylenate cyclodextrin, zeolites, such as FLAVITH, and fragrances.
After the skin has been formed by melting the powder blend (A)+(B) on the hot mold, excess unmelted powder is removed and then the crosslinking can be continued or initiated by placing the skin in an oven at a temperature of between 200 and 350° C. for a time of between 10 s and 10 min. The skin is subsequently separated from the mold after cooling. It is also possible, in the second and third embodiment, to remove the skin from the mold and then crosslink it with moisture.
The compositions of the invention make it possible to obtain skins which have a very soft touch, which have a Shore A hardness of less than 90 without the use of liquid plasticizers, and which do not exhibit creep when hot. These skins advantageously have the following characteristics:
the thickness is between 0.6 and 1.1 mm
the tensile strength (TS) is at least 5 MPa
the elongation at break (EB) is at least 300%
the aging after 500 h at 100° C., expressed by the variation in elongation, is at most 40%
the aging after 250 h at 120° C., expressed by the variation in elongation at break, is at most 50%
the aging after 250 h at 120° C., expressed by the variation in the tensile strength, is at most 10%
the elongation after creep at 140° C. under a load of 0.5 bar is at most 30%
fogging, DIN 75201 (3 h at 100° C.): no deposition (by measuring the migration of phthalates)
abrasion resistance and abrasive wear resistance after 30 min: meets the standards
gloss: meets the standards
heat withstand (22 h at 100° C.): meets the standards.
EXAMPLES
Except when otherwise indicated, the compositions of the products (% of acrylate, and the like) and the compositions of the powders of the invention are by weight.
The following products were used:
LOTADER® 8900, an ethylene/methyl acrylate/glycidyl methacrylate (GMA) copolymer containing 28% acrylate and 7.8% GMA, with an MFI of 6;
LOTADER® 6660, an ethylene/ethyl acrylate/maleic anhydride (MAH) copolymer containing 27.5% acrylate and 2.9% MAH, with an MFI of 40;
LOTADER® 7500, an ethylene/ethyl acrylate/maleic anhydride (MAH) copolymer containing 20.0% acrylate and 3.0% MAH, with an MFI of 70;
LOTADER® AX 8999, an ethylene/butyl acrylate/glycidyl methacrylate (GMA) copolymer containing 28% acrylate and 1% GMA, with an MFI of 70;
XX 1275, a catalyst, dimethyltallowamine (DMTA) in the form of a 3% masterbatch in an ethylene/butyl acrylate/MAH copolymer containing 32% acrylate and 3% MAH, with an MFI of 7;
LUCALEN A3110M, an ethylene/butyl acrylate/acrylic acid copolymer containing 8% acrylate and 4% acrylic acid, with an MFI of 6-8 (190° 2.16 kg);
IRGANOX B 225, 1:1 IRGANOX 1010/IRGAFOS 168;
TACKIFYING RESIN, REGALITE R1125;
MM, a carbon black;
MAGNESIUM STEARATE, mixtures of 65% stearate salt and 25% palmitate salt;
AEROSIL R972 (from Degussa);
ACTIVE CARBON, 3S and CXV (from CECA).
The various constituents above were reduced to a powder with a particle size of 200 μm by cryogenic milling.
The various compositions of the invention were prepared by blending the constituents in a powder blender. Skins were prepared by the slush molding technique. The mold was brought to a temperature of 250° C. in an oven. The mold, removed from the oven, was subsequently covered with an excess of powder of the composition used. After approximately 10 s, the unmelted powder is removed by turning over the mold. The mold is then again brought to 250° C. in the oven for 3 min. The mold is subsequently cooled in cold water. The skin is subsequently removed from the mold. The compositions and the properties are collated in the following table 1.
Examples 5 and 6
Example 5 is a black skin and example 6 is a gray skin. These examples give better performance than examples 1 and 4 in terms of abrasion, mechanical properties, toxicity (no dimethylsulfamine), better heat aging resistance (antioxidants) and less odor (active carbon).
The manufacture of the powder is divided into various steps. This manufacture is identical for all the formulations.
1. Compounding of the Formulation Based on LOTADER 8900 (=A) and LOTADER 7500 (=B) (Example 5).
The following formulations A were compounded in a Leistritz twin-screw extruder with venting, at a temperature of 160° C., and formulations B were compounded in a Leistritz twin-screw extruder with venting, at a temperature of 180° C.
Formulation A
Formulation B
Example 5 (black)
(in parts)
(in parts)
LOTADER 8900
96.0
—
LOTADER 7500
—
68
REGALITE R1125 resin
2.0
2.0
IRGAFOS 168
0.4
0.4
IRGANOX 1010
1.0
1.0
MM, carbon black
1.0
1.0
LUCALEN M 3110
—
28.0
Active carbon 3S
1.0
1.0
Active carbon CXV
1.0
1.0
2. Dry Blend of the Granules of the 2 Components in Defined Proportions
The A and B granules were dry-blended with the A/B mass ratio=1.575.
3. Manufacture of the Powder by Cryogenic Grinding and Incorporation of Additives
The formulations were then cryogenically ground into a powder having a particle size of 200 μm and then 2% of magnesium stearate and 0.6% of AEROSIL silica were added to the high-speed mixer.
4. Slush Molding
The mold was treated at 100° C. with a mold-release agent and heated at 120° C. for 20 min. (Chem-Trend S.A. Mono Coat MC-708A) and taken up to a temperature of 250-300° C. in an oven. Next, the mold removed from the oven was covered with an excess amount of powder of the composition used. After about 10 s, the unmelted powder was removed by turning the mold upside down. The mold was then heated again in the oven at 250-300° C. for 1-5 min. The mold was then cooled in cold water. The skin was then removed from the mold.
The compositions and properties of the formulations of examples 5 and 6 are the following:
Example 5
Example 6
(black)
(gray)
Compound
(in parts)
(in parts)
LOTADER 8900
55.7
54.6
LOTADER 7500
26.3
26.3
LUCALEN M 3110
10.8
10.1
IRGANOX 1010
1
—
IRGAFOS 168
0.4
—
IRGANOX B225
—
1
REGALITE R1125 resin
2
2
TiO 2
2.9
Active carbon 3S
1.0
1.0
Active carbon CXV
1.0
1.0
MM, carbon black
1
0.3
Addition by dry blending
Magnesium stearate
2
2
AEROSIL R 972
0.6
0.6
Properties
Tensile strength (MPa)
>6
>6
Elongation at break (%)
>300
>300
Creep 0.5 bar (min) 140° C.
>30
>30
Variation in elongation at
<50
<50
break after aging (250 h at
120° C.) (%)
Variation in tensile strength
<10
<10
after aging (250 h at 120° C.) (%)
Fogging, DIN 75201 (3 h at
No deposit
No deposit
100° C.)
TABLE 1
Ex. 1
Ex. 2
Ex. 3
Ex. 4
Ex. 7
Ex. 8
LOTADER 8900
3.48
3.48
24.4
28.4
17.4
LOTADER 6600
63.2
18.8
63.2
49.9
51.6
41
LOTADER AX
79.2
23.7
39.6
8999
XX 1275
2
2
2
2
Losses in g,
0.075/
0.0196
Taber test
0.018
Mean losses in g,
4.6
Taber test
Standard
4.0
deviation of the
losses
Creep resistance
Holds
Holds
Holds
at 120° C.
30 min
30 min
30 min
without load with
3 min of
post-smoothing at
250° C. | The invention concerns a crosslinkable composition of functionalized polyolefin powder comprising a functionalized polyolefin (A) having an MFI of at least 20 (190° C. 2.16 kg), a product (B) having a function for crosslinking (A), the composition having a grain size distribution between 100 and 400 μm. Said composition is useful for slush moulding, for thermoforming sheets or injection on an insert. | 2 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims the priority of German Application Nos. 196 33 823.9 filed Aug. 22, 1996 and 197 22 581.0 filed May 30, 1997, which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] This invention relates to an apparatus for conveying and readying coiler cans, particularly between two consecutive drawing frames of a processing line. The apparatus is of the type which includes a first conveyor track having, for the coiler cans, a first conveying device extending along the conveyor track. A second conveyor track having a second conveying device extends perpendicularly from the first conveyor track for a transverse conveyance of the coiler cans. A can carrier element is provided for transferring the coiler cans from the first (incoming) conveyor track to the second (transverse) conveyor track.
[0003] In a known apparatus as disclosed in German Offenlegungsschrift (application published without examination) 41 30 463 the second (transverse) conveyor track has a guide track having a central guide slot. Underneath the guide track a conveyor chain circulates on which coiler can carriers are mounted in fixed distances. The carriers project from the guide slot to such an extent that they are capable of engaging and pulling the coiler cans situated on the conveyor track. The upper run of the chain moves towards a drawing frame. A chain-supporting end sprocket is arranged in such a manner underneath the can delivery station that a can carrier which emerges from the guide slot at the end sprocket engages the coiler can at its lower edge and thus may pull the empty coiler can on the first conveyor track. The second conveying device of the second (transverse) conveyor track may be switched on only if the chain of the first conveying device is stationary and a coiler can is in a suitable position. The two conveying devices are operatively coordinated with one another by means of a control device in such a manner that one coiler can is always situated at the mouth of the conveying device. During the conveyance of the coiler cans the conveyor chain must always be positioned such that no coiler can carrier projects from the guiding slot at the transfer location. The second (transverse) conveying device is switched on only when an empty coiler can to be transferred comes to a halt, and then a coiler can carrier of the chain pulls the coiler can at the coiler can bottom edge from the first conveying device of the first conveyor track into the second conveying device of the second (transverse) conveyor track. It is a disadvantage of such prior art structures that the two conveying devices are necessarily coupled to one another to perform a coordinated operation, that is, they are not independent from one another. It is a further drawback that because of the fixed distances of the coiler can carriers from one another an accumulation of the coiler cans on the second (transverse) conveyor track is not possible.
SUMMARY OF THE INVENTION
[0004] It is an object of the invention to provide an improved apparatus of the above-outlined type from which the discussed disadvantages are eliminated and which, in particular, makes possible a mutually independent motion of the first (supplying) conveying device and the second (transverse) conveying device and also makes possible an accumulation of the coiler cans.
[0005] This object and others to become apparent as the specification progresses, are accomplished by the invention, according to which, briefly stated, the apparatus for conveying coiler cans includes a first conveyor track having an outlet end; a first conveying device for moving the coiler cans on and along the first conveyor track; a second conveyor track having an inlet end and being arranged at generally right angles to the first conveyor track; a second conveying device for moving the coiler cans on and along the second conveyor track; a first drive for operating the first and second conveying devices; a separate transfer device for moving a coiler can from the outlet end of the first conveyor track into the inlet end of the second conveyor track; and a second drive for operating the transfer device.
[0006] By virtue of the fact that a separate transfer device is associated with the conveying devices of the two perpendicularly arranged conveyor tracks, an independent motion of the two conveying devices is possible. In this manner, a separation of functions is effected: the transfer of the coiler cans from the first conveyor track to the second conveyor track and the conveyance of the coiler cans thereon are performed by two different devices. Further, in contrast to the known apparatus, the conveying devices do not have a plurality of coiler can carriers, so that an accumulation of the coiler cans (for example, in a mutually contacting relationship) is advantageously feasible.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] [0007]FIG. 1 is a schematic top plan view of a coiler can conveyor system according to the invention.
[0008] [0008]FIG. 2 is an enlarged schematic top plan view of one part of the structure of FIG. 2, showing additional details.
[0009] [0009]FIGS. 3 a and 3 b are sectional views taken along line III-III of FIG. 2 illustrating a coiler can in two different positions.
[0010] [0010]FIG. 4 is a schematic perspective view of an intake table of a drawing frame, showing coiler cans in an operational position.
[0011] [0011]FIG. 5 is a block diagram illustrating the control of the various drives and components for the conveyor system according to the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0012] Turning to FIG. 1, two drawing frames 1 and 4 of a sliver processing line are arranged in series wherein the drawing frame 1 is the upstream machine and the drawing frame 4 is the downstream machine as viewed in the order of consecutive sliver processing. The drawing frame 1 has an intake table 2 , a drawing unit 3 and a sliver depositing device 8 (having a rotary coiler head), whereas the drawing frame 4 has an intake table 5 , a drawing unit 6 and a sliver depositing device 9 (having a rotary coiler head). The drawing frame 1 and/or 4 may be an HS model manufactured by Trützschler GmbH & Co. KG, Mönchengladbach, Germany.
[0013] Also referring to FIG. 4, the drawing unit 6 of the downstream drawing frame 4 is supplied with sliver 10 from coiler cans 13 ′ a, 13 ′ b and 13 ′ c standing in a creel row 11 underneath supply rollers 18 a - 18 f of an intake table 5 . The coiler cans are supported in the creel row 11 on a conveyor track 15 . To the sliver delivery device 8 of the upstream drawing frame 1 there extends a conveyor track (supply track) 21 from an outlet end of the creel row 11 for supplying empty cans to the sliver delivery device 8 . A conveyor track (removal track) 22 for the sliver-filled cans extends from the sliver delivery device 8 . The conveyor track 15 is arranged perpendicularly to the supply track 21 and the removal track 22 . A conveyor track 23 and the removal track 22 are connected with one another by means of a further conveyor track 25 . The conveyor tracks 15 , 21 , 22 , 23 and 25 have respective conveying devices 17 , 20 , 19 , 24 and 26 for moving the coiler cans along the conveyor tracks.
[0014] The coiler can conveyor system 7 thus comprises essentially the conveyor track 15 , the supply conveyor track 21 , the removal conveyor track 22 and the conveyor tracks 23 and 25 which are all joined end-to-end and form a closed-circuit track assembly arranged in a rectangular pattern such that the conveyor track 15 extends parallel to the conveyor track 25 whereas the conveyor tracks 21 , 22 and 23 are parallel to one another. The solid-line arrows A, B, C and D indicate the path of conveyance of the full cans 13 ′ whereas the outlined (empty) arrows E and F indicate the path of conveyance of the empty cans 13 ″. The empty cans 13 ″ are pushed by a rotary coiler can exchanger (turnstile) 27 which rotates in the direction G, from the supply track 21 to underneath the rotary coiler head of the sliver delivery device 8 . At that location the cans are then filled with sliver 10 ( 13 ′″ indicates a partially filled can) and thereafter they are pushed as full cans 13 ′ by the turnstile 27 onto the removal track 22 . The coiler cans 13 ′, 13 ′ which circulate in the closed coiler can system are conveyed in a forward direction as indicated by the arrows A-F. The arrangement of the coiler can conveying system shown in FIG. 1 is particularly space saving.
[0015] According to FIG. 2, the conveying devices 17 , 19 , 20 , 24 and 26 are arranged close to the floor. Each conveying device has two parallel running conveyor belts 17 a, 17 b; 19 a, 19 b; 20 a, 20 b; 24 a, 24 b and 26 a, 26 b which circulate about end rollers 17 1 to 17 4 ; 19 1 to 19 4 ; 20 1 to 20 4 ; 24 1 to 24 4 and 26 1 to 26 4 . The conveying devices may be designed, for example, as described in published German Patent Application 195 09 928.1. The end rollers of the belts of the same belt pair are, at each belt end, arranged coaxially to one another.
[0016] Considering FIGS. 1 and 2 together, between two adjoining conveyor tracks 22 , 25 ; 25 , 23 ; 23 , 15 ; and 15 , 21 a respective, short circulating endless transfer belt 28 , 29 , 30 and 31 is provided to function as a can transfer device. In each instance the can transfer device is arranged on the receiving conveyor track of the two adjoining conveyor tracks. Thus, the transfer belt 28 is arranged on the conveyor track 25 to receive cans from the conveyor track 22 ; the transfer belt 29 is arranged on the conveyor track 23 to receive cans from the conveyor track 25 ; the transfer belt 30 is arranged on the conveyor track 15 to receive cans from the conveyor track 23 ; and the transfer belt 31 is arranged on the conveyor track 21 to receive cans from the conveyor track 15 . The transfer belts 28 , 29 , 30 and 31 which circulate about end rollers 28 a, 28 b; 29 a, 29 b; 30 a, 30 b; and 31 a, 31 b are arranged parallel to the conveyor belts 26 a, 26 b; 24 a, 24 b; 17 a, 17 b; and 20 a, 20 b, respectively. In each instance, the end roller at the inlet end of the transfer belt is in alignment with the end rollers at the inlet ends of the respective conveyor belts. Expediently, the outer surface of the upper run of the transfer belts 28 , 29 , 30 and 31 is at a slightly lower height level than that of the outer faces of the upper runs of the respective conveyor belts 26 a, 26 b; 24 a, 24 b; 17 a, 17 b; and 20 a, 20 b, and further, the effective length of each transfer belt 28 , 29 , 30 and 31 approximately corresponds to the diameter of the coiler cans. At the outer face of each transfer belt 28 , 29 , 30 and 31 a respective carrier element such as a pin 32 , 33 , 34 and 35 is arranged which, when situated on the upper run of the associated transfer belt, projects upwardly beyond the height level of the transporting surface of the respective conveyor from which transfer by the transfer belt is effected. The arrows A through F indicate the direction of motion of the upper belt run of the conveyor belts and the transfer belts associated with the respective conveyor belts.
[0017] As shown in FIG. 3 a, a can 13 ′ is situated on the conveyor belts 24 a, 24 b at the end of the conveyor track 23 . The coiler can has a bottom 36 ′ from which extends a peripheral, downwardly oriented terminal rim 36 ″ which, together with the underface of the can bottom 36 ′, defines a depression 36 . The can 13 ′ projects laterally outwardly beyond the conveyor belts 24 a, 24 b and thus the end roller 30 a of the transfer belt 30 is situated underneath that region of the coiler can 13 ′ which projects laterally beyond the conveyor belt 24 b. When the coiler can 13 ′ is in its position shown in FIG. 3 a, on a command signal an electric motor 37 sets the transfer belt 30 in motion such that its upper and the lower runs move in the direction of the arrows I and K, respectively. As a result of this operation, the coiler can carrier 34 moves on the end roller 30 a from below upwardly and projects into the depression 36 of the coiler can. As the transfer belt 30 continues to move, the can carrier 34 engages the inside face of the can rim 36 ″ and pulls the coiler can 13 ′ in the direction N from the conveyor belts 24 a, 24 b of the conveyor track 23 onto the conveyor belts 17 a, 17 b of the conveyor track 15 . As the carrier 34 reaches the end of the upper run of the transfer belt 30 , it travels downwardly out of its operational range about the end roller 30 b and then travels in the reverse direction on the lower run of the transfer belt 30 as shown in FIG. 3 b. At the same time, the conveyor belts 17 a, 17 b of the conveyor track 15 , circulated by the drive motor 38 move the coiler can 13 ′ forwardly in the direction O (designated at A and E in FIG. 1). The transfer belts 28 , 29 and 31 operate identically to the transfer belt 30 to shift coiler cans onto the respective conveyor tracks 25 , 23 and 21 .
[0018] As shown in FIGS. 1 and 4, and as described earlier, the conveyor track 15 forms part of the creel row 11 where the coiler cans are positioned for feeding the drawing unit 6 of the drawing frame 4 in the direction P, through a sliver guide (sliver intake trumpet) 46 .
[0019] In FIG. 5 an electronic control and regulating device 45 such as a microcomputer is shown to which there are connected the driving devices 38 - 42 , for example, drive motors for the serially arranged conveying devices 19 , 26 , 24 , 17 and 20 , the drive motor 43 for the turnstile 27 , sensors 44 for the path control of the coiler cans 13 ′, 13 ″ and drive motors (such as drive motor 37 ) for the transfer devices 28 , 29 , 30 , 31 . The sensors 44 may be located, for example, such that they emit a signal when a coiler can reaches the outlet end of a conveying device. Such sensors 44 are shown, for example, at the outlet end of the conveyor track 23 and at the outlet end of the conveyor track 15 . Such signal may be utilized for initiating the motion of the respective transfer belt 28 , 29 , 30 or 31 . The can conveying system 7 thus permits an automatic can conveyance and can replacement during operation between the drawing frames 1 and 4 .
[0020] By virtue of the independently driven conveying devices of the various conveyor tracks as well as the transfer devices, the electronic control and regulating device 45 , by means of a suitable energization and deenergization of the drives, makes possible an accumulation of the coiler cans on all or selected ones of conveyor tracks. In such an accumulated state the coiler cans are situated single file, in a mutually contacting position, as shown for the conveyor tracks 15 , 21 , 23 and 25 in FIG. 1. To achieve such an accumulated, mutually contacting state of the coiler cans, it is necessary to prevent motion of a selected can on the conveyor track to thus allow the conveying device to bring up consecutive cans behind the arrested can. In this manner the conveying device (that is, the conveyor belts on which the coiler cans stand) will slide underneath the stopped cans and will bring consecutively additional cans to be stopped by the coiler can immediately ahead. In the embodiment shown in FIG. 1, the conveyor tracks which join each other perpendicularly, include a lateral guide rail on each side. Thus, the conveyor track 15 has lateral guide rails 50 a, 50 b; the conveyor track 21 has lateral side rails 51 a, 51 b; the conveyor track 22 has lateral side rails 52 a, 52 b; the conveyor track 23 has lateral side rails 53 a, 53 b; and the conveyor track 25 has lateral side rails 54 a, 54 b.
[0021] The lateral guide rails provide, at the outlet end of the conveyor tracks 15 , 22 , 23 and 24 a stop or abutment so that in case the transfer device at the inlet of the adjoining conveyor track is idle, the coiler can at the outlet of the preceding conveyor track will be immobilized, thus allowing the cans to accumulate therebehind. For example, the side rail zone 53 a′ of the side rail 53 a will abut and stop any coiler can arriving at the outlet end of the conveyor track 25 , provided that the transfer device 29 of the conveyor track 23 is idle. Similar side rail zones serve as stops for the coiler cans arriving at the outlet end of the conveyor tracks 15 , 22 and 23 .
[0022] For abutting and stopping a coiler can at the outlet end of the conveyor track 21 , that is, within the operating range of the turnstile 27 , expediently a gate 55 is provided, having a control unit 56 , connected to the electronic control and regulating device 45 as shown in FIG. 5. The gate 55 may be in a lowered, operative position in which it acts as a stop for the leading coiler can on the conveyor track 21 whereas in its raised, inoperative position it will allow the turnstile 27 to move the coiler can away from the conveyor track 21 . It is noted that such a coiler can arresting and releasing arrangement is disclosed in U.S. patent application Ser. No. 08/617,328 filed Mar. 28, 1996 which is hereby incorporated by reference. It will be understood that the gating device 55 , 56 , may be arranged at any desired location of a selected conveyor track.
[0023] It will be understood that the above description of the present invention is susceptible to various modifications, changes and adaptations, and the same are intended to be comprehended within the meaning and range of equivalents of the appended claims. | An apparatus for conveying coiler cans, includes a first conveyor track having an outlet end; a first conveying device for moving the coiler cans on and along the first conveyor track; a second conveyor track having an inlet end and being arranged at generally right angles to the first conveyor track; a second conveying device for moving the coiler cans on and along the second conveyor track; a first drive for operating the first and second conveying devices; a separate transfer device for moving a coiler can from the outlet end of the first conveyor track into the inlet end of the second conveyor track; and a second drive for operating the transfer device. | 3 |
RELATED APPLICATIONS
[0001] This application claims priority from Mexican Application Serial No. MX/a/2013/006149 filed May 31, 2013, which is incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
[0002] Present invention describes a dispenser for additives such as detergent and chlorine whose structure allows for completely dispensing the washing additives without leaving residues, particularly for an automatic washing machine preferably for top loading washers, without excluding front loading washers.
BACKGROUND
[0003] It is common nowadays to see that automatic washers have at least one dispenser for additives, such as detergent, bleach, softener, among others.
[0004] When the dispensing of additives is automatic, the user may place the additives into their own compartments, and by means of the dispenser controller they are activated at a determined time, during the washing cycle, to dispense the additive within the container for the treatment of the garments.
[0005] It is well known to dilute the additives to be dispensed with water to achieve uniform distribution of the additives within the tub or basket, whichever the case may be, instead of becoming concentrated in a single area of the container.
[0006] Additionally, depending on the geometry of the deposit of the dispenser, and of the water supply device, problems can arise, such as: agglomerations of the powdered additives due to the formation of large lumps of additive in such a way that they are too large to accomplish passing through the dispenser which generally has a groove like shape or they are too wide; another of the problems is when low dilution between the water mixture and the additive exists causing part of the additive to remain floating on the upper part of the supplied water flow, thus impeding it from exiting the dispenser; it has also been found that a significant amount of the additive is sometimes pushed to the ends or another deposit area of the dispenser where it remains as a residue, while the flow of diluted water with the remaining additive exits the dispenser; or simply overflow of the additive occurs given the excess of supply of the same by the user given that the dispenser does not have a maximum amount indicator of the amount to be placed, or overflow due to poor control of the supplied water pressure.
[0007] With the passage of time and use of the washing machine, any of the problems such as agglomeration, lack of dilution, residues or overflow can get to the point of reducing functionality of the dispenser, in addition to being aesthetically displeasing to the user.
[0008] The different documents which can be found in current literature related to additive dispensers, if they do address the above related questions, have not been able to successfully tackle them, as does present invention.
[0009] Among the various efforts which have been undertaken in the field of detergent dispensers, we highlight patent document U.S. Pat. No. 4,700,554 from 1986, where Carl E. Eichman et al makes reference to a granular additive dispenser which includes a separate recipient which can be inserted in order to dispense liquid detergent which makes it different than the additive dispenser of the present invention, which can function both for liquid as well as granulated detergent without using extra additions; in said patent U.S. Pat. No. 4,700,554, the water is supplied to the deposit in conventional manner where through a horizontal channel implemented solely as a means for the exit of the additive, discharges it directly into the tub, which can cause damage to the garments to be treated through direct chemical attack on the textile surface in such a manner, that given this, the additive dispenser of the present invention carries out the additive discharge between the tub and the basket thus avoiding direct contact with the garments to be washed; additionally, Carl E. Eichman in the same patent document U.S. Pat. No. 4,700,554 discloses in his dispenser downwardly inclined walls from the water supply entrance to the additive exit towards the tub, which for the purpose of efficiency in the sweeping and dispensing of the residues, said walls could be insufficient.
[0010] Another relevant document to be analyzed is document 20050144737 A1 US from 2005, where Jon Arthur Roepke et al references a system for dispensing additives to a washing machine which includes a removable deposit coupled to the main lid of the washing machine, where by means of a water valve connected to the deposit and a controller, water is introduced into the deposit to dilute the additive and dispense the diluted additive between the tub and the basket at a predetermined time; the advantage of counting with a removable dispenser for purposes of efficiency of dispensation results null, given that the residue problems arise during the washing cycle, not prior to or post the washing cycle, in addition to running the risk of misplacement, given the above, the additive dispenser of present invention is found fixed unto the front part, mechanically connected on the inner part to the main lid of the washing machine.
[0011] Another interesting document is US 20050229645 A1 by Jon Min Kim et al. This references an additive dispenser which is characterized by counting with a deposit, an upper cover lid and a lower cover lid, where the lower cover lid has a first water supply channel; afterwards a second channel is located which diverts the water from the first channel and supplies water to the additive deposit, both channels are connected by means of an auxiliary channel; afterwards the water is discharged to the deposit through a plurality of holes found along the length of the channels, where the next step is the diluted additive being released into the tub by means of a bellow; among the disadvantages which can be listed for document US 20050229645 A1, which even the author himself mentions, are the reduction of water flow pressure at the end of the channel opposite to the water entrance, which in present invention is solved thanks to the pressure regulator which has been included at the entrance of the additive dispenser; another disadvantage of Jong Min Kim's et al document is dispensation in such a direct manner into the tub as opposed to present invention, whose releasing of additives occurs between the tub and the basket.
[0012] It should also be mentioned that in 2005, Marcus Zsambeki in patent document number US 20050188730 A1 references an additive dispenser for a washing machine which comprises a box in the shape of an indentation and a sliding drawer set with a plurality of separated compartments for containing additives for washing or rinsing which have some entrances in the back part and through which water is supplied towards the compartment through one of the ends of the dispenser where additionally the dispenser has a channel to direct the entering water flow towards the lower part and towards the outside of the sliding drawer with the aspect of sweeping along with the residues; as opposed to the present invention, patent document number US 20050188730 A1 is only concerned with sweeping the residues which remain under and outside the deposit and ignore the residues which remain within the deposit itself; in addition to undertaking the releasing of detergent within the tub which can cause damages to the garments to be washed as was previously mentioned.
[0013] Now then, in 2007 Lonnie Joe Richman et al in patent document U.S. Pat. No. 7,900,486 references an additive dispenser which includes a housing made up of a collector which the water supply reaches, and a compartment where the additive is deposited. The water supplied into the collector is transported to the additive compartment through a set of holes found along the length of the wall which divides the collector from the compartment, where the mixing of the water and the additive is ejected by means of a siphon system and discharged between the tub and the basket; said holes rather than being useful for the releasing of the additive, can get to be a problem given that, as was previously mentioned, the exits or openings in the shape of grooves which are too narrow, can become obstructed given the additive agglomerations, which renders the dispenser inefficient; given the latter, present invention has avoided reduced spaces which run the risk of agglomerations or obstructions.
[0014] Now then, present invention proposes a configuration for an additive dispenser which has resulted in being highly effective for preventing or resolving the difficulties present in the dispensation as was detailed in the above mentioned documents, as well as other which commonly arise in dispensers.
BRIEF DESCRIPTION OF THE INVENTION
[0015] Present invention relates to an additive dispenser for wash, particularly, for use in automatic top loading washing machines for the treatment of laundry. However, the additive dispenser may be used in other household appliances, such as front loading washers for laundry or in dishwashers.
[0016] The additive dispenser of the present invention in its preferred embodiment is made up of two pieces, a cover lid and a container which allows for the decreasing of costs given that the configuration in said additive dispenser allows supplying water for wash, understood as wash water, whether it is fresh water arriving directly from external water supply or simply recycled water, in such a way that said wash water supplies each of the additive deposits, comprising one water entrance for all the deposits, in addition to decreasing manufacturing and assembly complexity.
[0017] The cover and the container are found joined preferably by a plastic joining method such as adhesive, hot plate, ultrasound, snaps, welding, pressure closure or a combination of the above, in order to avoid leaks due to high work pressures to which it could potentially be subjected to.
[0018] The additive dispenser of the present invention is found set on the front part, mechanically connected on the inner part of the main cover lid of the washing machine preferably by means of screws; its position on the front part of the washing machine is for the ease of the user when supplying detergent or any other additive to the deposit. Additionally, an indicator for the maximum level has been included, which forms part of the main cover lid, in light of studies showing that upon lacking this type of indicator may cause some users to add a larger amount than the amount recommended by the manufacturer, which leads to or entails improper functioning of the dispenser, particularly in cases in which the dispensation is by means of a siphon system, given that the wash liquor excess formed by detergents or other additives mixed in the wash water cause the siphon system be activated prior to its time, which causes over-foaming or residue problems in the garments to be laundered.
[0019] The configuration of the additive dispenser in its preferred embodiment comprises two compartments, one for dispensing detergent and the other for dispensing bleach.
[0020] The detergent, whether it is in powder or in liquid form, falls directly into the reservoir tub cover of the sub-washer passing through a grill which allows the wash liquor to reach between the tub and the basket, where for practical purposes the sub-washer is defined as the complete washing machine except for the cabinet thereof; at the exit of the deposit at least one safety grill is found in order to avoid the passage of different objects other than detergent and cause the drainage pump or other devices in the washing machine to become damaged.
[0021] On the other hand, the second deposit of the additive dispenser of the present invention, in its preferred embodiment, is destined for dispensing bleach, which as opposed to the detergent compartment is contained in such a way that the wash liquor is extracted by means of a siphon system, in addition to also being dispensed between the tub and the basket through the tub cover reservoir of the sub-washer.
[0022] The additive dispenser of the present invention may also have a homogenizing flow system located at the entrance of the additive dispenser and which may have a set of parts in the additive dispenser which grant it efficiency in the correct distribution of wash water which enters from the supply hose for efficient sweeping of residues, given that for a range of entrance wash water pressure of 20.68 kPa (3 psi)-82.74 kPa (12 psi) the flow pressure of the wash water within the additive dispenser is uniform, this thanks to the flow homogenizer system found in the present invention, which additionally aids in avoiding water overflowing outside of the additive dispenser, given the high pressures. Said flow homogenizing system is made up by a connection nozzle with the wash water supply hose; the end of the connection nozzle which is connected to the hose has a larger diameter than the exit end towards the additive dispenser, forming a truncated cone where immediately afterwards a segment is found which is neck shaped with equal depth to the diameter of the end of the lesser diameter of the truncated cone where an increase in velocity is produced in the flow of wash water which enters and passes through a neck which directs the water flow towards a damping tank which is nothing more than a closed space formed by the container and the cover of the additive dispenser by means of a coupling groove and a coupling joint. Said damping tanker receives the wash water after this crosses the inner part of the connection nozzle, where its function is that of homogenizing the entrance flow of the wash water dissipating kinetic energy which said flow acquires upon increasing its velocity, with the purpose that the additive dispenser works in the same manner both for low pressures (from 20.68 kPa (3 psi)) as well as for high pressures (up to 82.74 kPa (12 psi)).
[0023] Afterwards, the perimeter pathway is located which is found in fluid communication with the damping tank which is formed by the container and the cover through which the wash water flow travels with a constant pressure thanks to the flow homogenizing system. Now then, the first section of the additive dispenser of the present invention is found in fluid communication with the damping tank and passes through the bleach deposit, where thanks to a coupling joint which binds perfectly with a coupling groove of the cover, it avoids that the majority of the wash water which enters, remains in the bleach deposit, and in this way can travel to the detergent deposit where the problem of residue dispensation is more relevant. Between the cover and the container a plurality of deflectors are formed whose end purpose is: controlling high pressures, directing wash water within the deposits and avoid overspills. The first releasing of wash water from the perimeter pathway towards the detergent deposit is by means of a linear deflector located between the first section of the additive dispenser of the present invention and the second section of the additive dispenser of the present invention, which channels a part of the wash water which travels through the perimeter pathway towards the detergent deposit and at the same time a smaller quantity of the bleaching deposit by means of a dividing wall which counts with an inclination to allow the passage of wash water and in this manner activate the siphon system, which is formed by a cylindrical body surrounded by the set of reinforcement ribs on the base and a depression which surrounds it in the lower part and which forms part of the container of the additive dispenser, in conjunction with the cover lid which is mushroom shaped, of the siphon system, which may also have reinforcement ribs on the cover lid and which forms part of the cover of said additive dispenser. The remainder of the entering wash water continues travelling through the perimeter pathway where the flow passing area of said perimeter pathway is decreased given a segment of the protrusion of the linear deflector located on the second section of the additive dispenser of the present invention causing an increase in the wash water velocity, thus ensuring that despite the amount of wash water decreasing given the releasing at the first deflection, the wash water continue running in a uniform fashion in the remaining sections of the perimeter pathway.
[0024] Afterwards, between the second section of the additives dispenser and the third section of the additives dispenser of the present invention, a curved deflector is found which forms part already of the detergent deposit and which given the velocity increase of the wash water flow upon passing through the reduced passage area, the wash water is re-circulated and released through said curved deflector with an effect similar to the water evacuation in a toilet, where said turbulence allows sweeping in an effective manner along with the detergent residues, jointly with a bay found at the bottom of the detergent deposit which aids in the correct dispensing of residues.
[0025] Between the third section of the additives dispenser of and the fourth section of the additives dispenser of the present invention, a bi-directional dispenser is found which divides the remaining wash water, which remains flowing through the perimeter pathway to the detergent deposit and to the bleach deposit, thus ensuring complete dispensing of additives. In the fourth section of the additives dispenser of the present invention a waterfall is found which comprises a recess and is found in fluid communication with said perimeter pathway ensuring, through surface tension, at least a wash water thread to said siphon system to maintain it active and in order to release the wash water in its entirety.
BRIEF DESCRIPTION OF THE FIGURES
[0026] The particular features and advantages of present invention, as well as other aspects of the invention, shall become apparent from the following specification, taken in context with the accompanying figures, which are:
[0027] FIG. 1 is a front view of a cross cut of an automatic top loading washing machine for clothes.
[0028] FIG. 2 is a lateral view of a cross cut of an automatic top loading washing machine for clothes.
[0029] FIG. 3 is a front view of a cross cut of an automatic top loading washing machine for clothes where some of the rods which make up the suspension rod set are shown.
[0030] FIG. 4 is an upper view of the sub-washer of an automatic top loading washing machine for clothes where the rod suspension set, the grill and the spray deflector are highlighted.
[0031] FIG. 5 shows a code diagram of the functioning of the additive dispenser of present invention.
[0032] FIG. 6 is an isometric view of the connection between the additive dispenser of the present invention to the supply hose in connection with the filling and electronic control valves.
[0033] FIG. 7 is an isometric view of the additive dispenser of the present invention in its preferred embodiment.
[0034] FIG. 8 is an isometric view of the assembly of the cover and the container of the additive dispenser of the present invention in its preferred embodiment highlighting the holes through which the additive is deposited.
[0035] FIG. 9 is an upper view of the maximum level indicator of the additive dispenser of the present invention in its preferred embodiment, which forms part of the main cover lid of the washing machine.
[0036] FIG. 10 is an exploded view of the additive dispenser where the cover lid and the container of said additive dispenser in its preferred embodiment, as well as some of its parts are highlighted.
[0037] FIG. 11 is an isometric view of the homogenizing flow system located in the container of the additive dispenser, highlighting the connection nozzle and the end with the greater diameter through which the wash water enters into the additive dispenser.
[0038] FIG. 12 is an isometric view of the homogenizing flow system highlighting the end with the smaller diameter, the neck, the damping tank and the coupling junction which together with the coupling groove (not visible in this figure) allow for the damping tank to be limited to one area.
[0039] FIG. 13 is an isometric view of a portion of the cover of the additive dispenser of said invention, highlighting the lid of the damping tank which thanks to the coupling groove which it has, they are joined by means of a snap.
[0040] FIG. 14 is an isometric view of the portion of the container of the additive dispenser of the present invention in its preferred embodiment which corresponds to the first section of the additive dispenser of the present invention, highlighting the bleach deposit, the perimeter pathway which is found in fluid communication with the flow homogenizing system and the linear deflector.
[0041] FIG. 15 is an isometric view of a portion of the container of the additive dispenser of the present invention highlighting the linear deflector in fluid communication with the perimeter pathway, the protrusion of the linear deflector and the place presenting a reduction in the passage area of the perimeter pathway; additionally, the dividing wall between the bleach deposit and the detergent deposit with its corresponding slope can be seen.
[0042] FIG. 16 is an isometric view of a portion of the inner part of the cover of the additive dispenser of the present invention highlighting the upper protrusion of the linear deflector and the coupling groove.
[0043] FIG. 17 is an isometric view of a portion of the additive dispenser container of the present invention in its preferred embodiment corresponding to the second section of the additive dispenser of the present invention and to the third section of the additive dispenser of the present invention, highlighting the curved deflector and the bidirectional deflector which are found in fluid communication with the perimeter pathway.
[0044] FIG. 18 is an isometric view of a portion of the cover of the additive dispenser of the present invention highlighting the curved protrusion corresponding to the curved deflector located in the container.
[0045] FIG. 19 is an isometric view of a portion of the detergent deposit of the additive dispenser of the present invention highlighting the bay in the detergent deposit, as well as two safety grills in the additive exit which impede the passage of foreign objects.
[0046] FIG. 20 is an isometric view of the additive dispenser container in its preferred embodiment highlighting the bleach deposit and the detergent deposit.
[0047] FIG. 21 is an isometric view of a portion of the detergent deposit container of the present invention highlighting the bay in the lower part of the detergent deposit, as well as the curved deflector and the bidirectional deflector in fluid communication with the perimeter pathway.
[0048] FIG. 22 is an isometric view enhanced at a portion of the cover of the additive dispenser of the present invention in its preferred embodiment, highlighting the protrusion in “V” shape corresponding to the bidirectional deflector located in the container of said additive dispenser.
[0049] FIG. 23 is an isometric view of a portion of the container of the additive dispenser of the present invention in its preferred embodiment corresponding to the bleach deposit where the lower part of the siphon system which shows the cylindrical body with its corresponding reinforcement ribs on the base and the depression surrounding the cylindrical body of the siphon system are highlighted; additionally, the waterfall which is found in fluid communication with the perimeter pathway can be seen.
[0050] FIG. 24 is an isometric view of a portion of the cover of the additive dispenser of the present invention in its preferred embodiment, highlighting the mushroom shaped cover lid of the siphon system with its corresponding reinforcement ribs on the cover lid.
[0051] FIG. 25 is an isometric view of a cross cut of the washing machine where the additive dispenser of the present invention and the tub cover reservoir, as well as the grill through which the wash liquor falls between the tub and the basket are highlighted.
DETAILED DESCRIPTION OF THE INVENTION
Theoretical Approach
[0052] Present invention is focused on washing machines, particularly on dispensers for additives for automatic top loading washing machines. However, the additive dispenser may be used in other household appliances, such as front loading washers for laundry or in dishwashers.
[0053] One of the many benefits which the automation of household appliances has brought into the home is that of minimizing the complexity of common cleaning tasks, making life simpler and lessening complexities for persons, providing benefits of convenience and speed when performing these daily activities.
[0054] A striking example is the technological breakthrough in washing machines, automating them to such an extent that the user only has to deposit the garments and merely remove them afterwards and they are ready to use; one of the features of the clothing washing machines which has achieved becoming fully automated, is the use of additive dispensers wherein the additive is dispensed at a particular time during the wash cycle.
[0055] The present invention describes the improvement to additive dispensers for top loading washing machines, wherein an additive dispenser with multiple deposits for additives comprises a single water entrance sufficient for sweeping with each one of the deposits in an efficient and clean manner, is proposed; said wash water distribution to all and each one of the additive dispensers is undertaken thanks to a perimeter pathway which passes through all the deposits releasing wash water in a strategic way by means of a plurality of deflectors.
Preferred Embodiment of the Invention
[0056] The washing machine 10 illustrated in FIGS. 1 , 2 , 3 is the top loading or vertical axis type, and thus it comprises a cabinet 41 from which is fastened the set of suspension rods 39 ; said set of suspension rods 39 support the weight of the tub 11 along with the remainder of its accessories of said cabinet 41 , in addition to acting as a damper to the vibrations which are originated during the washing process. Thus, the tub 11 is hung from said set of suspension rods 39 by means of ears set on the lower part of said tub 11 as can be seen in FIG. 4 . On said tub 11 the remaining peripheral equipment is mounted unto, such as the motor 23 , optionally a planetary gear for reduction 26 , which in an alternative embodiment to the present invention can be omitted, adjusting the relation to the pulleys 24 , that is, the pulley with the greatest diameter shall be adjusted over the inner shaft 27 , which itself shall receive energy from the electric motor 23 thanks to the pulley arrangement 24 and the band (not shown); optionally, the shaft 27 on its upper end is coupled to a planetary gear 26 with the end goal of decreasing angular velocity and thus obtain greater torque, the exit shaft of the planetary gear 26 is reintegrated into a shaft 27 , which on its upper end seats the agitator 48 ; optionally, the inner shaft 27 on its lower end has the pulley 24 with the greatest diameter coupled unto it and on its upper end has the agitator 48 coupled unto it. The hollow shaft 28 houses in its inner part the inner shaft 27 , additionally said hollow shaft 28 is mechanically coupled to a clutch 30 which can cause both shafts 27 , 28 rotate together or in an independent manner; said hollow shaft 28 is mechanically coupled to the center of the basket or to the “hub” 34 , so that when said shafts 27 , 28 are clutched rotating together, the hollow shaft 28 will transmit energy to the basket 12 so that it may turn with the agitator 48 .
[0057] The basket 12 is crowned with a balance hoop 29 which counteracts the unbalancing caused by the rearranging of the objects to be washed within the basket 12 . The tub 11 on the other hand, has on its upper end a tub cover 15 assembled unto it, which houses a grill 21 , as well as a spray deflector 19 , both illustrated in FIG. 4 . On the other hand, the cabinet 41 is sheltered by the main cover 32 which covers the upper part of the washing machine 10 ; said main cover 32 serves as a support for a crest 33 where the electronic components are housed, such as the electronic control 40 , drivers (not shown), pressure switch (not shown), filling valves 37 etc., as well as the door or wash cover lid 31 through which the objects to be washed are introduced. The additive dispenser 60 of the present invention is mechanically connected to the inner part of the main cover 32 of the washing machine 10 , preferably by means of screws.
[0058] FIG. 5 shows a schematic diagram of the electronic control connection 40 to the additive dispenser parts 60 which it controls.
[0059] The electronic control 40 sends a pulse for a determined period of time to the driver of the filling valves (not shown) to energize and activate the filling valves 37 , allowing for the passage of a volume of wash water which is herded in the direction of the additive dispenser 60 through which a supply hose 61 which is connected to the entrance of said filling valves 37 and fastened to said filling valves 37 by means of a backwards clasp 62 , which itself is connected on the other end to the connection nozzle 71 of the additive dispenser 60 and fastened to said connection nozzle 71 by means of a frontal clasp 77 as is detailed in FIG. 6 . FIGS. 7 , 8 show the additive dispenser 60 , of the present invention which is composed in its preferred embodiment with two pieces which are the cover 63 and the container 64 preferably molded by some thermoplastic injection preferably joined by a plastic joining method such as adhesive, hot plate, ultrasound, welding, pressure closure, snaps among others, or a combination of the same, to be careful with the joining between the cover 63 and the container 64 , knowing that it is not preferable to have leaks in said joint as this could run the risk of causing that around the washing machine 10 a water puddle can be formed exposing the user to electric discharges given that said leaks mainly present themselves when the dispensers operate at high pressures, which is the case with the additive dispenser 60 , of the present invention, which is also designed to work under high pressures. Additionally, a maximum level indicator 69 has been included as is shown in FIG. 9 which forms part of any main cover 32 of washing machine 10 , given that as studies show that when this type of indicator 69 is missing, it can cause some users to use a larger amount of detergent or chemical product than that which is recommended by the manufacturer, which prompts or leads to improper functioning of the additive dispenser 60 of the present invention. Particularly in cases where dispensation is carried out by means of a siphon system 90 , given that the excess of additives causes the siphon system 90 be activated prior to its time, which in turn causes over-foaming or residue problems in the garments to be washed.
[0060] Present invention in its preferred embodiment comprises two deposits 65 , 66 for the dosing of wash additives as is shown in FIG. 10 , one deposit is for the bleach 65 and the other for detergent 66 with the peculiarity of one water entrance for sweeping the additive for both deposits 65 , 66 .
[0061] This is so that in order to work with a same wash water flow pressure independently from the pressure which it has going through the supply hose 61 knowing that in practice it is considered as a low work pressure starting from 20.68 kPa (3 psi) and up to 82.74 kPa (12 psi) is considered as high work pressure, so that to the additive dispenser 69 of the present invention, a flow homogenizing system 70 has been included, with the end goal that the additive dispenser 60 may work efficiently both for low pressures as well as with high pressures. Said flow homogenizing system 70 is composed in the first place by a connection nozzle 71 which also in addition to allow the connection to the supply hose 61 , fastens said connection nozzle 71 by means of a frontal clasp 77 , where the referred connection nozzle 71 allows modifying the wash water flow velocity with which it is travelling, thanks to its inner part having a truncated cone shape with the intention of varying the passage area entrance of the additive dispenser 60 , thus increasing the velocity at which the wash water arrives, in such a way that the greater diameter end 72 of the referred to connection nozzle 71 is located near the supply hose 61 and distant from the inner part of the additive dispenser, and where through the other side of the lesser diameter end 73 consequently, is located near the inner part of the additive dispenser 60 and distant from the supply hose 61 . Additionally, together with the connection nozzle 71 , immediately after the smaller diameter end 73 , a segment is found neck shaped 76 which directs the wash water flow towards the next element of the flow homogenizing system 70 of the additive dispenser 60 .
[0062] A damping tank 74 has been included as part of the flow homogenizing system 70 with the objective of dissipating the kinetic energy which was gained by the wash water flow, as a consequence of increased velocity which it acquires upon passing through the inner part of the connection nozzle 71 thus functioning in a hydraulic jump manner, knowing that the hydraulic jump is a sharp rise of the water level in a channel or in a container space as a consequence of the delay which a water current suffers when it flows at a high velocity causing a dissipation of kinetic energy. In the case of the flow homogenizing system 70 of the additive dispenser 60 the hydraulic jump is produced by the damping tank 74 in charge of dissipating the kinetic energy of the wash water flow after having passed through the inner part of the connection nozzle 71 , in such a way that said damping tank 74 is an enclosed space with a semi-circular cross section formed by a lower section called the hydraulic cushion 78 which fits together with an upper section called the damping tank cover lid 75 by means of a coupling joint 81 in the damping tank 74 and a coupling groove 82 as part of the damping tank cover lid 75 , as the damping tank 74 is part of the container 64 where in turn the damping tank cover lid 75 forms part of the cover 63 of the additive dispenser 60 .
[0063] In this way, after the wash water has passed through the neck 76 , it arrives at the damping tank 74 falling unto the hydraulic cushion 78 where the wash water volume is radially spread acquiring a fast stall speed whereas the height of the wash water increases abruptly, given that the wash water flow passes from having a fast stall speed to having a slow stall speed after having experienced the impact within the damping tank 74 . Afterwards, as the height of the wash water increases in the damping tank 74 , the wash water acquires its own drafting scheme upon coming into contact with the perimeter pathway 80 , where said perimeter pathway 80 is found in fluid communication with the damping tank 74 in such a way that starting from the wash water arriving to said perimeter pathway 80 , which is formed by the cover 63 and the container 64 , the wash water volume remains with the same flow scheme which will avoid overflowing or in the opposite case, insufficient flow pressure for the correct dispensation of the additives. The elements which make up the flow homogenizing system 70 are shown in FIGS. 11 , 12 and 13 .
[0064] The referred perimeter pathway 80 is a space which runs along the borders of both additive deposits 65 , 66 of the additive dispenser 60 , in its preferred embodiment, additionally serving as a means through which the wash water is lead towards each one of the referred deposits 65 , 66 in such a way that the wash water in the channel is strategically release at certain points through the plurality of deflectors 83 , 84 , 85 which are formed by the container 64 and the cover 63 which serve to direct the wash water which travels through the referred perimeter pathway 80 towards the inside of the deposits 65 , 66 in addition to helping prevent overspills outside the additive dispenser 60 .
[0065] FIG. 15 presents a first section 120 of the additive dispenser 60 of present invention through which the wash water begins to travel within the perimeter pathway 80 which additionally is delimited in a manner similar to the damping tank 74 , by a coupling joint 81 and a coupling groove 82 with the objective that the wash water remains in its course without remaining in the bleach deposit 65 , attempting in such a manner that the greatest amount of wash water be used for sweeping the residues of the detergent deposit 66 where the residue is problematic.
[0066] Afterwards, between the first section 120 of the additive dispenser 60 of present invention and a second section 121 of the additive dispenser 60 , the first releasing of wash water is undertaken by means of a linear deflector 83 which is formed by a deflection and a protrusion 103 of the linear deflector in the container 64 together with an upper protrusion 117 of the linear deflector which forms part of the cover 63 illustrated in FIGS. 15 and 16 in such a way that the protrusion 103 of the linear deflector of the container 64 eases the redirecting of wash water flow mainly towards the detergent deposit 66 . However, between the bleach deposit 65 and the detergent deposit 66 there is a dividing wall 102 whose upper base comprises a slope 106 which at the moment in which the wash water falls through a linear deflector 83 , said slope 106 allows a part of that wash water to reach the bleach deposit 65 beginning with the activation of the siphon system 90 which it counts with. As part of the second section 121 of the additive dispenser 60 , a protrusion segment 103 of the linear deflector in the container 64 is found in an obstructive manner over the referred perimeter pathway 80 , causing a reduction in the passage area 107 , with the objective of originating an increase in the wash water flow velocity which remains in the channel of the referred perimeter pathway 80 in order to continue with sufficient pressure to maintain itself in the channel over said perimeter pathway 80 . Additionally the segment of perimeter pathway which corresponds to the second section 121 of the additive dispenser 60 of comprises a safety protrusion 104 which ensures the channeling of the wash water towards the next releasing point of the wash water after having crossed the reduced passing area segment 107 .
[0067] The second releasing of wash water takes place between the second section 121 of the additive dispenser 60 of present invention as well as the third section 122 of the additive dispenser 60 of the present invention, even within the limits of the detergent deposit 66 , by means of a curved deflector 84 as part of the container 64 in conjunction with a curved protrusion 116 which forms part of the cover 63 illustrated in FIGS. 17 , 18 and 19 . At this releasing point, given the wash water velocity after having crossed the reduced passing area segment 107 , it decreases given the referred curved deflector 84 with a re-circulated effect similar to that which can be seen in the water evacuation within a toilet, in such a way that together with the feature which the detergent deposit 66 comprises a downwardly inclined wall 101 which surrounds it, the wash water is released from the curved deflector 84 with a certain degree of turbulence in order to achieve efficient sweeping of residues. In addition to the downwardly inclined wall 101 , the detergent deposit 66 comprises a bay 100 at the bottom provided with a group of reinforcement protrusions 105 which maintain their original shape, that is flat and horizontal in such a way that it can store a water film when it is released by means of the curved deflector 84 to ensure that the missing detergent particles be picked up. Nearby the referred bay 100 an exit orifice for the wash liquor 114 of the referred detergent deposit 66 is found, comprising at least one safety grill 113 with the objective of avoiding the passage of foreign objects which could damage the washing machine 10 .
[0068] Subsequently, after the majority of the wash water which is found travelling through the perimeter pathway 80 and which is released by means of the curve deflector 84 , the remaining wash water remains in its channel through the perimeter pathway 80 , which similar to the second section 121 of the additive dispenser 60 of present invention, it comprises a safety protrusion 104 which allows for the wash water which remains traveling through said perimeter pathway 80 , be directed towards the next releasing point, which is through a bidirectional deflector 85 found between the third section 122 of the additive dispenser 60 and the fourth section 123 of the additive dispenser 60 , which is formed by the container 64 plus a protrusion in “V” shape 115 found on the cover 63 in such a way that the wash water which remains flowing in the perimeter pathway 80 after having passed through the curved deflector 84 , is released dividing itself in two directions, one towards the detergent deposit 66 falling with the same re-circulated effect as the curved deflector 84 , thus ensuring the sweeping of possible residues on the remainder of the inclined wall 101 of the detergent deposit 66 , and on the other part in the direction towards the bleach deposit 65 , where said curved deflector is presented in FIGS. 20 , 21 and 22 .
[0069] The bleach deposit 65 , as opposed to the detergent deposit 66 contains the wash liquid, subsequently extracting it by means of a siphon system 90 which is illustrated in FIGS. 23 , 24 which is comprised of a cylindrical body 91 with reinforcement ribs at the base 93 which avoid that through use, the cylindrical body 91 of the siphon system 90 does not get to correctly fit into the mushroom shaped cover lid 92 of the siphon system 90 , which forms part of the cover 63 in the same manner with a set of reinforcement ribs 94 on the cover lid. In addition to the wash water which is released by means of the bidirectional deflector 85 , the bleach deposit 65 also comprises a waterfall 86 formed by a wall 87 of the waterfall 86 and a base 88 of the waterfall 86 which are found in a recessed manner on the wall of the bleach deposit 65 on the fourth section 123 of the additive dispenser 60 , in such a way that given the surface tension said water fall 86 provides the siphon system 90 with at least one thread of wash water entrapping it into a sagging 95 which encircles the cylindrical body 91 of the siphon system 90 keeping it active and extracting at the same time the chlorine volume deposited into said bleach deposit 65 .
[0070] It is in this way, that the additive dispenser 60 , of the present invention directs the wash liquor, so that in a jet like manner, it falls down through the tub cover reservoir 22 over the grill 21 as can be seen in FIG. 25 , where said grill 21 allows the passage of the wash liquor between the tub 11 and the basket 12 , avoiding contact with the objects to be washed, thus depositing the wash liquor at the bottom of the basket 12 , which allows for uniformly mixing of the chemicals with the water without pouring the chemicals directly over the garments to be washed which can cause spots due to the chemical attack on the surface of said garments as a consequence of poor dilution of the chemicals with the water.
[0071] The next step is the electronic control 40 sends a pulse to the driver of the spray pump (not shown), which allows this to supply the wash liquor during the width of the referred pulse to the spray deflector 19 , spraying the wash liquor unto the objects to be washed which are found placed within the basket 12 .
[0072] The duration of the referred pulse having expired, the steps are repeated for a determined amount of time, or at least for as long as one revolution of the basket 12 , in such a manner that the objects to be washed which are contained within the basket 12 get soaked with the wash liquor which has accumulated at the bottom of the tub 11 .
[0073] This is followed by once having transferred all or the great majority of the water volume accumulated at the bottom of the tub 11 towards the objects to be washed, the electronic control 40 , sends a pulse to the driver of the motor (not shown) remembering that the clutch 30 is found in a dehydrated manner. This allows the basket 12 to rotate the objects to be washed contained in said basket 12 , where upon rotating at a certain velocity for a determined amount of time the wash liquor is extracted from the textiles and is collected at the bottom of the tub 11 .
[0074] Followed by the electronic control 40 sending a pulse for a determined amount of time to the driver of the drain pump (not shown) so that it may begin to pump the wash liquor from the bottom of the tub 11 towards outside through the drain hose (not shown) which is found at the exit.
[0075] Variations to the structure of the additive dispenser described in the present invention may be foreseen by those with expertise in the field. However, it should be understood that present specification corresponds to the preferred embodiment of the invention which is merely for illustrative purposes, and should not be considered as limitative to the invention. All modifications within the scope of the invention described which are not mentioned, as could be alternative to the configuration of the perimeter pathway 60 of the additive dispenser of the present invention should be considered within the scope of the attached claims. | An additive dispenser for an automatic washing machine includes a container with a compartment for a wash additive. The compartment has a siphon system and a water fall on a wall of the compartment. A flow homogenizing system at the entrance of the dispenser includes: (a) a connection nozzle with an inner part, where the connection nozzle allows communication with a source of wash water, and the inner part of the connection nozzle has two areas with a different size to produce a Venturi effect; and (b) a damping tank with a container and a cover. The homogenizing system homogenize the wash water flow which enters. A perimeter pathway for the transfer of the wash water is formed by the container and the cover; and a deflector to direct the wash water flow which travels through the perimeter pathway. | 3 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. patent application having Ser. No. 13/313,084, filed Dec. 7, 2011, titled “WATER CONTROL FIXTURE HAVING BYPASS VALVE”, which is a continuation of U.S. patent application Ser. No. 12/643,616 filed Dec. 21, 2008, issued as U.S. Pat. No. 8,091,793 issued Jan. 10, 2012, which is a continuation of U.S. patent application Ser. No. 11/827,926, filed Jul. 12, 2007, issued as U.S. Pat. No. 7,648,078 issued Jan. 19, 2010, which is a continuation of U.S. patent application Ser. No. 11/173,572, filed Jul. 1, 2005, issued as U.S. Pat. No. 7,287,707 issued Oct. 30, 2007, which is a continuation of U.S. patent application Ser. No. 10/006,970, filed Dec. 4, 2001, issued as U.S. Pat. No. 6,929,187 on Aug. 16, 2005, which patent is a continuation-in-part of U.S. patent application Ser. No. 09/697,520 filed Oct. 25, 2000, issued as U.S. Pat. No. 6,536,464 issued Mar. 25, 2003, and claimed priority to U.S. Provisional Application No. 60/251,122 filed Dec. 5, 2000, each of which are hereby incorporated by reference in their entirety.
BACKGROUND OF THE INVENTION
The present invention relates generally to faucets and bypass valves for use in home or industrial water distribution systems that supply water to various fixtures at different temperatures through different pipes. More particularly, the present invention relates to faucets having bypass valves that are thermostatically controlled so as to automatically bypass water that is not at the desired temperature for use at the fixture. Even more particular, the present invention relates to faucets having an integral thermostatically controlled bypass valve.
Home and industrial water distribution systems distribute water to various fixtures, including sinks, bathtubs, showers, dishwashers and washing machines, that are located throughout the house or industrial building. The typical water distribution system brings water in from an external source, such as a city main water line or a private water well, to the internal water distribution piping system. The water from the external source is typically either at a cold or cool temperature. One segment of the piping system takes this incoming cold water and distributes it to the various cold water connections located at the fixture where it will be used (i.e., the cold water side of the faucet at the kitchen sink). Another segment of the piping system delivers the incoming cold water to a water heater which heats the water to the desired temperature and distributes it to the various hot water connections where it will be used (i.e., the hot water side of the kitchen faucet). At the fixture, cold and hot water either flow through separate hot and cold water control valves that are independently operated to control the temperature of the water into the fixture by controlling the flow rate of water from the valves or the water is mixed at a single valve that selectively controls the desired temperature flowing into the fixture.
A well known problem common to most home and industrial water distribution systems is that hot water is not always readily available at the hot water side of the fixture when it is desired. This problem is particularly acute in water use fixtures that are located a distance from the hot water heater or in systems with poorly insulated pipes. When the hot water side of these fixtures is left closed for some time (i.e., overnight), the hot water in the hot water segment of the piping system sits in the pipes and cools. As a result, the temperature of the water between the hot water heater and the fixture lowers until it becomes cold or at least tepid. When opened again, it is not at all uncommon for the hot water side of such a fixture to supply cold water through the hot water valve when it is first opened and for some time thereafter. At the sink, bathtub or shower fixture located away from the water heater, the person desiring to use the fixture will either have to use cold or tepid water instead of hot water or wait for the distribution system to supply hot water through the open hot water valve. Most users have learned that to obtain the desired hot water, the hot water valve must be opened and left open for some time so that the cool water in the hot water side of the piping system will flow out ahead of the hot water. For certain fixtures, such as dishwashers and washing machines, there typically is no method of “draining” away the cold or tepid water in the hot water pipes prior to utilizing the water in the fixture.
The inability to have hot water at the hot water side of the fixture when it is desired creates a number of problems. One problem is having to utilize cold or tepid water when hot water is desired. This is a particular problem for the dishwasher and washing machine fixtures in that hot water is often desired for improved operation of those fixtures. As is well known, certain dirty dishes and clothes are much easier to clean in hot water as opposed to cold or tepid water. Even in those fixtures where the person can let the cold or tepid water flow out of the fixture until it reaches the desired warm or hot temperature, there are certain problems associated with such a solution. One such problem is the waste of water that flows out of the fixture through the drain and, typically, to the sewage system. This good and clean water is wasted (resulting in unnecessary water treatment after flowing through the sewage system). This waste of water is compounded when the person is inattentitive and hot water begins flowing down the drain and to the sewage system. Yet another problem associated with the inability to have hot water at the hot water valve when needed is the waste of time for the person who must wait for the water to reach the desired temperature.
The use of bypass valves and/or water recirculation systems in home or industrial water distribution systems to overcome the problems described above have been known for some time. The objective of the bypass valve or recirculation system is to avoid supplying cold or tepid water at the hot water side of the piping system. U.S. Pat. No. 2,842,155 to Peters describes a thermostatically controlled water bypass valve, shown as FIG. 2 therein, that connects at or near the fixture located away from the water heater. In his patent, the inventor discusses the lack of hot water problem and describes a number of prior art attempts to solve the problem. The bypass valve in this patent comprises a cylindrical housing having threaded ends that connect to the hot and cold water piping at the fixture so as to interconnect these piping segments. Inside the housing at the hot water side is a temperature responsive element having a valve ball at one end that can sealably abut a valve seat. The temperature responsive element is a metallic bellows that extends when it is heated to close the valve ball against the valve seat and contracts when cooled to allow water to flow from the hot side to the cold side of the piping system when both the hot and cold water valves are closed. Inside the housing at the cold water side is a dual action check valve that prevents cold water from flowing to the hot water side of the piping system when the hot water valve or the cold water valve is open. An alternative embodiment of the Peters' invention shows the use of a spiral temperature responsive element having a finger portion that moves left or right to close or open the valve between the hot and cold water piping segments. Although the invention described in the Peters' patent relies on gravity or convection flow, similar systems utilizing pumps to cause a positive circulation are increasingly known. These pumps are typically placed in the hot water line in close proximity to the faucet where “instant” hot water is desired.
U.S. Pat. No. 5,623,990 to Pirkle describes a temperature-controlled water delivery system for use with showers and eye-wash apparatuses that utilize a pair of temperature responsive valves, shown as FIGS. 2 and 5 therein. These valves utilize thermally responsive wax actuators that push valve elements against springs to open or close the valves to allow fluid of certain temperatures to pass. U.S. Pat. No. 5,209,401 to Fiedrich describes a diverting valve for hydronic heating systems, best shown in FIGS. 3 through 5 , that is used in conjunction with a thermostatic control head having a sensor bulb to detect the temperature of the supply water. U.S. Pat. No. 5,119,988 also to Fiedrich describes a three-way modulating diverting valve, shown as FIG. 6 . A non-electric, thermostatic, automatic controller provides the force for the modulation of the valve stem against the spring. U.S. Pat. No. 5,287,570 to Peterson et al. discloses the use of a bypass valve located below a sink to divert cold water from the hot water faucet to the sewer or a water reservoir. As discussed with regard to FIG. 5 , the bypass valve is used in conjunction with a separate temperature sensor.
A recirculating system for domestic and industrial hot water heating utilizing a bypass valve is disclosed in U.S. Pat. No. 5,572,985 to Benham. This system utilizes a circulating pump in the return line to the water heater and a temperature responsive or thermostatically actuated bypass valve disposed between the circulating pump and the hot water heater to maintain a return flow temperature at a level below that at the outlet from the water heater. The bypass valve, shown in FIG. 2 , utilizes a thermostatic actuator that extends or retracts its stem portion, having a valve member at its end, to seat or unseat the valve. When the fluid temperature reaches the desired level, the valve is unseated so that fluid that normally circulates through the return line of the system is bypassed through the circulating pump.
Despite the devices and systems set forth above, many people still have problems with obtaining hot water at the hot water side of fixtures located away from the hot water heater or other source of hot water. Boosted, thermally actuated valve systems having valves that are directly operated by a thermal actuator (such as a wax filled cartridge) tend not to have any toggle action. Instead, after a few on-off cycles, the valves tend to just throttle the flow until the water reaches an equilibrium temperature, at which time the valve stays slightly cracked open. While this meets the primary function of keeping the water at a remote faucet hot, leaving the valve in a slightly open condition does present two problems. First, the lack of toggle action can result in lime being more likely to build up on the actuator because it is constantly extended. Second, the open valve constantly bleeds a small amount of hot or almost hot water into the cold water piping, thereby keeping the faucet end of the cold water pipe substantially warm. If truly cold water is desired (i.e., for brushing teeth, drinking, or making cold beverages), then some water must be wasted from the cold water faucet to drain out the warm water. If the bypass valve is equipped with a spring loaded check valve to prevent siphoning of cold water into the hot water side when only the hot water faucet is open, then the very small flow allowed through the throttled-down valve may cause chattering of the spring loaded check valve. The chattering can be avoided by using a free floating or non-spring loaded check valve. It is also detrimental to have any noticeable crossover flow (siphoning) from hot to cold or cold to hot with any combination of faucet positions, water temperatures, or pump operation.
U.S. Pat. No. 6,536,464 the disclosure of which is incorporated herein as fully set forth and having some of the same inventors and the same assignee as the present invention, describes an under-the-sink thermostatically controlled bypass valve and water circulating system with the bypass valve placed at or near a fixture (i.e., under the sink) to automatically bypass cold or tepid water away from the hot water side of the fixture until the temperature of the water reaches the desired level. The system described in U.S. Pat. No. 6,536,464 includes a single small circulating pump that is placed between the water heater and the first branching in the hot water supply line which supplies the fixture having a bypass valve so as to pressurize the hot water piping system and facilitate bypassing of the cold or tepid water.
The public is accustomed to purchasing faucets for lavatories, bathtubs, showers, kitchen sinks and etc. that can be readily repaired, usually by removing a top-mounted handle and bonnet, and replacing a faucet washer or other seal or seat. In recent designs, the sealing action occurs within a replaceable cartridge, which can be easily replaced by the home repair person. None of the known prior art devices include the use of an integral thermostatically controlled bypass valve to bypass water as described above. However, for a thermal bypass valve to be included in a faucet, it is necessary that it meet the same expectation for ease of repair as the standard faucet. There are several advantages to location of the thermal bypass valve within the faucet itself and being accessible from the top, which include: (1) elimination of the clutter resulting from extra hoses located below the sink and the need to do plumbing and maintenance below the sink; (2) elimination of the under-the-sink hoses, which by their very presence add potential leak paths at each end of each hose; (3) a new feature that a faucet manufacturer can use to define its top-of-the-line faucet, which can stimulate sales to those customers who like to have the latest in convenience; and (4) the bypass valve can be serviced by the home repair person or, if desired, professional plumber in a standing position in a manner which is already learned from the maintenance of existing design faucets.
BRIEF DESCRIPTION OF THE INVENTION
In an exemplary embodiment, a water control fixture is provided including a housing having a plurality of ports defining a hot water inlet port, a bypass port, and a fixture outlet port, wherein water is dispensed via the fixture outlet port. At least one operating valve is disposed in the housing for controlling a flow of water from the hot water inlet port to the fixture outlet port. A bypass valve is disposed in the housing for controlling a flow of water from the hot water inlet port to the bypass port.
Optionally, the plurality of ports includes a cold water port configured to be in fluid communication with a cold water supply line, wherein the at least one operating valve may control a flow of water from the cold water port to the fixture outlet port. The bypass valve may control a flow of water from the hot water inlet port to the cold water port. Optionally, the bypass valve may opens to permit a flow of water from the hot water inlet port to the bypass port based on an activation condition. The bypass valve may be thermostatically controlled and may control the flow of water from the hot water inlet port to the bypass port until the temperature of the water at the hot water inlet port is at a preset level. Optionally, the bypass port may be configured to be in fluid communication with one of a dedicated return line and a cold water supply line. Optionally, the housing may represent a faucet and include at least one handle provided on the housing, wherein the handle is joined to the at least one operating valve to control the flow of water from the hot water inlet port and the fixture outlet port.
In another embodiment, a water control fixture is provided including a housing having a plurality of ports defining a hot water inlet port, a bypass port, and a fixture outlet port, wherein water is dispensed via the fixture outlet port. At least one handle is attached to the housing for controlling the flow of water from the hot water inlet port to the fixture outlet port. A bypass member is disposed in the housing for controlling a flow of water from the hot water inlet port to the bypass port.
In a further embodiment, a water control fixture is provided including a housing having a chamber and a plurality of ports in fluid communication with the chamber. The plurality of ports define a hot water inlet port, a bypass port, and a fixture outlet port, wherein water is dispensed via the fixture outlet port. A flow control unit is received within the chamber and is configured to be selectively positioned in fluid communication with the plurality of ports for controlling the flow of water from the hot water inlet port to the fixture outlet port and for controlling the flow of water from the hot water inlet port to the bypass port.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a water distribution system that utilizes a water control fixture (faucet) having a thermostatically controlled bypass valve of the present invention;
FIG. 2 is a side view of the preferred thermally sensitive actuating element, shown in its unmodified condition, for use in the bypass valve of the present invention;
FIG. 3 is a front view of a typical fixture body for a single handle faucet;
FIG. 4 is a side view of the single handle faucet in FIG. 3 ;
FIG. 5 is a top view of the faucet body housing for the faucet of FIG. 3 ;
FIG. 6 is a side cross-sectional view of the faucet body housing for the faucet of FIG. 3 ;
FIG. 7 is a bottom view of the faucet body housing of the faucet of FIG. 3 ;
FIG. 8 is a sectional view of a bypass valve cartridge body for use with the present invention;
FIG. 9 is a sectional view of the bypass valve cartridge body taken at 90 degrees to FIG. 8 ;
FIG. 10 is a sectional view of the bypass valve cartridge body of FIG. 8 with a bypass valve and other components place therein;
FIG. 11 is a cross-sectional view of the side of a shower faucet that utilizes a cartridge insert (not shown) for controlling the flow of water through the faucet showing the placement of a bypass valve therein;
FIG. 12 is a cross-sectional view of the side of a modified ball control mechanism for use in single handle faucets;
FIG. 13 is a top view of the ball of FIG. 12 ;
FIG. 14 is a side view of the ball of FIG. 12 ;
FIG. 15 is a cross sectional view of modified replaceable cylindrical valving cartridge used in some faucets as adapted for the present invention;
FIG. 16 is a side view of a valve member used with dual handle, single spout faucets;
FIG. 17 is side cross-sectional view of the upper half of a cartridge placed in the valve member of FIG. 16 ;
FIG. 18 is chart showing the operational characteristics of the bypass valve of the present invention when in use with a water distribution system; and
FIG. 19 is a side cross-sectional view of a modified thermal actuator showing modifications to reduce problems with lime buildup.
DETAILED DESCRIPTION OF THE INVENTION
With reference to the figures where like elements have been given like numerical designations to facilitate the reader's understanding of the present invention, the preferred embodiments of the present invention are set forth below. The enclosed figures and drawings are illustrative of the preferred embodiments and represent a preferred way of configuring the present invention. Although specific components, materials, configurations and uses are illustrated, it should be understood that a number of variations to the components and to the configuration of those components described herein and in the accompanying figures can be made without changing the scope and function of the invention set forth herein.
In the accompanying drawings of the various preferred embodiments of a water control fixture of the present invention, the water control fixture is shown as faucet 10 . However, other water control fixtures may be adaptable to the thermal bypass valve features described herein (i.e., solenoid valve used on home laundry washing machines). A typical water distribution system 12 utilizing faucet 10 of the present invention is illustrated in FIG. 1 . The water distribution system 12 typically comprises a supply of cold water 14 , such as from a city main or water well, that supplies cold water directly to faucet 10 through cold water line 16 and water to hot water heater 18 so that it may heat the water and supply hot water to faucet 10 through hot water line 20 . Cold water line 16 connects to faucet 10 through cold water inlet 22 and hot water line 20 connects to faucet 10 through hot water inlet 24 , as explained in more detail below.
The preferred system 12 of the present invention utilizes a small circulating pump 26 of the type used in residential hot water space heating. A very low flow and low head pump is desirable because a larger (i.e., higher head/higher flow) pump mounted at the typical domestic water heater 18 tends to be noisy. This annoying noise is often transmitted by the water pipes throughout the house. In addition, if the shower (as an example) is already in use when pump 26 turns on, whether the first start or a later cyclic turn-on, the sudden pressure boost in the hot water line 20 from a larger pump can result in an uncomfortable and possibly near-scalding temperature rise in the water at the shower head or other fixture in use. The smaller boost of a “small” pump (i.e., one with a very steep flow-head curve) will result in only a very small and less noticeable increase in shower temperature. In the preferred embodiment, the single, small pump 26 needs to provide only a flow of approximately 0.3 gpm at 1.0 psi pressure. In accordance with pump affinity laws, such a “small” pump requires a very small impeller or low shaft speed. The inventors have found that use of a very small impeller or low shaft speed also precludes formation of an air bubble in the eye of the impeller, which bubble may be a major cause of noise. Such a small steep curve pump may, however, constitute a significant pressure drop in the hot water line 20 when several fixture taps are opened simultaneously (such as a bathtub and the kitchen sink). To avoid reduced flow in those installations having a relatively low volume pump, a check valve 28 can be plumbed in parallel with pump 26 or incorporated within the pump housing, to pass a flow rate exceeding the pump's capacity around pump 26 . When pump 26 is powered and flow demand is low, check valve 28 prevents the boosted flow from recirculating back to its own inlet. With check valve 28 plumbed around pump 26 , it is advantageous to place an orifice 30 in the pump discharge to provide a simple manner to achieve the desired very steep flow-head curve from available stock pump designs. A single pump 26 located at or near the water heater 18 in its discharge piping will boost the pressure in the hot water pipes somewhat above that in the cold water pipes (i.e., perhaps one to three feet of boost). With this arrangement only one pump 26 per plumbing system (i.e., per water heater 18 ) is required with any reasonable number of remote faucets 10 (i.e., the typical number used in residences) equipped with bypass valves. This is in contrast to those systems that require multiple pumps, such as a pump at each fixture where bypassing is desired.
If desired, pump 26 can operate twenty-four hours a day, with most of the time in the no flow mode. However, this is unnecessary and wasteful of electricity. Alternatively, pump 26 can have a timer 32 to turn on the pump 26 daily at one or more times during the day just before those occasions when hot water is usually needed the most (for instance for morning showers, evening cooking, etc.) and be set to operate continuously for the period during which hot water is usually desired. This still could be unnecessary and wasteful of electricity. Another alternative is to have the timer 32 cycle pump 26 on and off regularly during the period when hot water is in most demand. The “on” cycles should be of sufficient duration to bring hot water to all remote fixtures 10 that are equipped with a bypass valve, and the “off period” would be set to approximate the usual time it takes the water in the lines to cool-down to minimum acceptable temperature. Yet another alternative is to equip pump 26 with a normally closed flow switch 34 sized to detect significant flows only (i.e., those flows that are much larger than the bypass valve flows), such as a shower flowing. For safety purposes, the use of such a switch 34 is basically required if a cyclic timer 32 is used. The switch 34 can be wired in series with the motor in pump 26 . If the switch 34 indicates an existing flow at the moment the timer calls for pump 26 to be on, the open flow switch 34 will prevent the motor from starting, thereby avoiding a sudden increase in water temperature at the fixture 10 (i.e., particularly if it is a shower) being utilized. The use of such switch 34 accomplishes several useful objectives, including reducing electrical power usage and extending pump life if hot water is already flowing and there is no need for the pump to operate, avoiding a sudden temperature rise and the likelihood of scalding that could result from the pump boost if water is being drawn from a “mixing” valve (such as a shower or single handle faucet) and allowing use of a “large” pump (now that the danger of scalding is eliminated) with its desirable low pressure drop at high faucet flows, thereby eliminating the need for the parallel check valve 28 required with a “small” pump.
By using a time-of-day control timer 32 , pump 26 operates to maintain “instant hot water” only during periods of the day when it is commonly desired. During the off-cycle times, the plumbing system 12 operates just as if the faucet 10 having bypass valves and pump 26 were not in place. This saves electrical power usage from pump operation and, more importantly, avoids the periodic introduction of hot water into relatively un-insulated pipes during the off-hours, thereby saving the cost of repeatedly reheating this water. The time-of-day control also avoids considerable wear and tear on pump 26 and the bypass valve in faucet 10 . Considerable additional benefits are gained by using a cyclic timer 32 , with or without the time-of-day control. In addition to saving more electricity, if a leaky bypass valve or one not having toggle action is used, there will be no circulating leakage while the pump 26 is cycled off, even if the valve fails to shut off completely. Therefore, a simple (i.e., one not necessarily leak tight) valve may suffice in less demanding applications. Having the leakage reduced to just intermittent leakage will result in reduced warming of the cold water line 16 and less reheating of “leaking” re-circulated water.
The bypass valve assemblies 36 utilized with the present invention have a thermally sensitive actuating element 38 , an example of which is shown in FIG. 2 , for thermostatically controlling bypass valve 36 . Actuating element 38 is preferably of the wax filled cartridge type, also referred to as wax motors, having an integral poppet rod member 40 , as best shown in FIG. 2 . Rod member 40 comprises poppet 42 attached to piston 44 with an intermediate flange 46 thereon. The end of poppet 42 is configured to seat directly against a valve seat or move a shuttle (i.e., spool or sleeve valves) so as to close a passage. These thermostatic control elements 38 are well known in the art and are commercially available from several suppliers, such as Caltherm of Bloomfield Hills, Mich. The body 48 of actuating element 38 has a section 50 of increased diameter, having a first side 52 and second side 54 , to seat against a shoulder or like element in a valve body. Piston 44 of rod member 40 interconnects poppet 42 with actuator body 48 . Actuating element 38 operates in a conventional and well known manner. Briefly, actuating element 38 comprises a blend of waxes or a mixture of wax(es) and metal powder (such as copper powder) enclosed in actuator body 48 by means of a membrane made of elastomer or the like. Upon heating the wax or wax with copper powder mixture expands, thereby pushing piston 44 and poppet 42 of rod member 40 in an outward direction. Upon cooling, the wax or wax/copper powder mixture contracts and rod member 40 is pushed inward by a bias spring until flange 46 contacts actuator body 48 at actuator seat 56 . Although other types of thermal actuators, such as bimetallic springs and memory alloys (i.e., Nitinol and the like) can be utilized in the present invention, the wax filled cartridge type is preferred because the wax can be formulated to change from the solidus to the liquid state at a particular desired temperature. The rate of expansion with respect to temperature at this change of state is many times higher, resulting in almost snap action of the wax actuating element 38 . The temperature set point is equal to the preset value, such as 97 degrees Fahrenheit, desired for the hot water. This is a “sudden” large physical motion over a small temperature change. As stated above, this movement is reacted by a bias spring that returns rod member 40 as the temperature falls.
Because the bypass valve 36 has little or no independent “toggle action,” after a few cycles of opening and closing, the valve tends to reach an equilibrium with the plumbing system, whereby the bypass valve 36 stays slightly cracked open, passing just enough hot water to maintain the temperature constantly at its setting. In particular plumbing systems and at certain ambient conditions, this flow is just under that required to maintain a spring loaded check valve cracked continuously open. In such a situation, the check valve chatters with an annoying buzzing sound. To avoid this occurrence, the spring may be removed from the check valve, leaving the poppet free floating. In the event that the hot water is turned full on at a time when the bypass valve 36 is open, thereby lowering the pressure in the hot water line 20 , and so inducing flow from the cold water line 16 through the open bypass valve 36 to the hot side, the free floating poppet will quickly close. There is no necessity for a spring to keep this check valve closed prior to the reversal in pressures.
Although not entirely demonstrated in early tests, it is believed that beneficial “toggle” action can be achieved with a bypass valve 36 of very simple mechanical design. If the motion of the thermal actuator 38 is made to lag behind the temperature change of the water surrounding it by placing suitable insulation around the actuator 38 or by partially isolating it from the water, then instead of slowly closing only to reach equilibrium at a low flow without reaching shutoff, the water temperature will rise above the extending temperature of the insulated actuator 38 as the valve approaches shutoff, and the piston 44 will then continue to extend as the internal temperature of the actuator 38 catches up to its higher surrounding temperature, closing the valve 36 completely. It is also believed that an insulated actuator 38 will be slow opening, its motion lagging behind the temperature of the surrounding cooling-off water from which it is insulated. When actuating element 38 finally begins to open the valve 36 and allow flow, the resulting rising temperature of the surrounding water will again, due to the insulation, not immediately affect it, allowing the bypass valve 36 to stay open longer for a complete cycle of temperature rise. Such an “insulated” effect may also be accomplished by use of a wax mix that is inherently slower, such as one with less powdered copper or other thermally conductive filler. An actuator 38 to be installed with insulation can be manufactured with a somewhat lower set point temperature to make up for the lag, allowing whatever valve 36 closing temperature desired.
An additional benefit of utilizing pump 26 in system 12 is that shut-off of a toggle action valve upon attainment of the desired temperature is enhanced by the differential pressure an operating pump 26 provides. If pump 26 continues to run as the water at the faucet 10 cools down, the pump-produced differential pressure works against re-opening a poppet type bypass valve 36 in faucet 10 . If pump 26 operates cyclically, powered only a little longer than necessary to get hot water to faucet 10 , it will be “off” before the water at valve 36 cools down. When the minimum temperature is reached, the thermal actuator 38 will retract, allowing the bias spring to open valve 36 without having to fight a pump-produced differential pressure. By-pass flow will begin with the next pump “on” cycle. An additional benefit to the use of either a time-of-day or cyclic timer 32 is that it improves the operating life of thermal actuator 38 . Because use of either timer 32 causes cyclic temperature changes in valve 36 (as opposed to maintaining an equilibrium setting wherein temperature is constant and the actuator 38 barely moves), there is frequent, substantial motion of the piston 44 in thermal actuator 38 . This exercising of actuator 38 tends to prevent the build-up of hard water deposits and corrosion on the cylindrical surface of actuator piston 44 and face of poppet 42 , which deposits could render the valve 36 inoperable.
Also inside valve 36 can be an over-travel spring (not shown) disposed between the first side 52 of the actuator body 48 and a stop located inside valve 36 to prevent damage to a fully restrained actuator 38 if it were heated above the bypass valve's maximum operating temperature and to hold the actuator 38 in place during operation without concern for normal tolerance. Use of an over-travel spring, which is not necessary for spool-type valves, allows movement of the actuator body 48 away from the seated poppet 42 in the event that temperature rises substantially after the poppet 42 contacts its seat. Without this relief, the expanding wax could distort its copper can, destroying the calibrated set point. The over-travel spring also holds the bias spring, rod member 40 and actuator body 48 in place without the need to adjust for the stack-up of axial tolerances. Alternatively, actuator 38 can be fixedly placed inside valve 36 by various mechanisms known in the art, including adhesives and the like. Over-travel spring, if used, can be held in place by various internal configurations commonly known in the art, such as a molded seat.
As there are a great many configurations and brands of faucets 10 , there are several different preferred designs of bypass valve 36 placement and arrangement to accommodate these many faucet configurations. For purposes of illustrating the present invention, various specific examples are set forth below. The following examples are representative of the types of uses to which the integral or in-faucet bypass valve 36 is suitable. The examples are for illustrative purposes only and are not intended to restrict the invention to particular uses, sizes or materials used in the examples.
For instance, there are several basic types of faucet assemblies, including those that have a single handle faucet assembly that mixes the hot and cold water and delivers a flow of water out the single spout based on the user's movement of the faucet's valve assembly. Another common type of faucet assembly is the dual handle, single spout faucet assembly that has separate handles for the hot and cold water. As with the single handle assembly, the hot and cold water are mixed prior to the spout based on the user's selection of the amount of flow of hot and/or cold water. A third, older arrangement is the use of completely separate faucets for hot and cold water. Although the different manufacturers of faucets may utilize different arrangements of valving components, different valving mechanisms and/or different valves to water supply line connections, the bypass valve system of the present invention is adaptable to all such known configurations. As set forth below, the primary selection in the use of the bypass faucet assembly of the present invention is whether to place the bypass valve in a stationary portion of the faucet, such as the hot water piping leading to the faucet or in a housing or block portion of the faucet, or to place the bypass valve in the moveable valving of the faucet. Selection of which location to place the bypass valve assembly will often be dictated by economics, preferences, limitations on the amount of space available, the current design of the faucet and/or the willingness to change.
Example 1
Single Handle Faucets w/Bypass Valve in Stationary Block
As is well known, single handle faucets, an example of which is shown as fixture body 60 , faucet 10 without its decorative covering, in FIGS. 3 and 4 , have both hot 24 and cold 22 water inlets connected to a housing or block 62 . Various internal valving means, such as pivoting and rotating ball 64 , selectively and adjustably control the volume and temperature of the flow of water by connecting the hot 20 and cold 16 lines, through hot and cold conduits 66 and 68 respectively (as shown in FIGS. 5 and 7 ), to a single outlet spout 70 through spout outlet 72 . In such designs, the thermal bypass valve 36 is preferably assembled into an easily replaceable cartridge 74 , shown best in FIGS. 8 , 9 and 10 , that can be located within the hot water conduit 66 of fixture body 60 (if the design provides such access) or in an added cavity 76 placed between and connected to the hot 24 and cold 22 inlets, as shown in FIG. 7 . In either case, the bypass valve 36 senses and is controlled by the temperature of the “hot” water in the fixture body 60 . When the “hot” water is cooled off due to long disuse, the bypass valve 36 will open, providing a conduit between the hot 24 and cold 22 inlets. If the hot water line pump 26 is then turned on, the boosted pressure in the hot water line 20 will produce flow through the open bypass valve 36 , bringing “hot” water to the fixture body 60 . In the above-mentioned arrangements, the flow of water from both hot 20 and cold 16 lines remains unimpeded due to the previously mentioned internal valving arrangement of the fixture body 60 . The flow from the hot line 20 through the bypass valve cartridge 74 to the cold line 16 is provided through molded or cast passages or cross-drilled holes, discussed below.
The single handle faucet body 60 with spherical ball valving means 64 , shown in FIGS. 3 and 4 , is a good example of a faucet design that can be easily and economically re-designed to include a bypass valve cartridge 74 in the stationary housing 62 . Use of this approach requires a new fixture body 60 to be installed, with a top-accessible, suitably sized cavity 76 to hold the bypass cartridge 74 and connect conduits 66 and 68 built into the fixture body 60 to accommodate the bypassed flow from the hot 20 to the cold 16 lines. FIGS. 5 through 7 show a modified and lengthened version of a Delta housing 62 that is used with the standard Delta faucet outer housing. The portion 78 above line AA (i.e., to the left of in FIG. 6 ) it is essentially an original Delta housing, with the addition of bore 76 . Below AA (i.e., to the right of in FIG. 6 ) is extension 80 . In the preferred use of the present invention, these sections 78 and 80 would be made in a single, integral housing 62 . Cavity 76 and the drilled and plugged cross passages 82 and 84 are added, and the top bore 86 is extended inward if and as much as is needed to accommodate any necessary devices, such as a ring or washer to hold cartridge assembly 74 in place in cavity 76 . Drilled passage 82 connects the cold water supply to cavity 76 near its top and drilled passage 84 connects the hot water line 20 to cavity 76 near its bottom.
FIGS. 8 and 9 show the bypass valve cartridge 74 , without its internal components, that is designed and configured to fit in cavity 76 . FIG. 10 shows the components, including thermal actuator 88 , assembled together as they would fit into cavity 76 . The thermal actuator 88 is a modified version of the actuator 38 that is used in U.S. Pat. No. 6,536,464 and shown in FIG. 2 herein. Water from hot water line 20 is carried through drilled hole 84 to the lower end of cavity 76 and flows up around and through the cartridge 74 to and through the open valve seat 90 (poppet 42 is shown closed into against O-ring 92 forming seat 90 in FIG. 10 ) into the check valve chamber 94 housing check valve 96 and out through the cross drilled hole 98 into an annulus 100 on the cartridge 74 . From annulus 100 , between O-rings 102 and 104 , the water flows through drilled passage 82 to the cold water supply. When sufficient water has flowed through the bypass valve 36 to exhaust the cooled-off water in the hot water supply line 20 and bring hot water to the bypass valve 36 , the thermal actuator 88 will cause piston 44 to extend, forcing poppet 42 into seat 90 to close off the flow. The seat O-ring 92 is held in place by spring 106 , which doubles as the bias or poppet return spring. In the preferred embodiment, thermal actuator 88 is held in place by a snap fit into the split cartridge 74 , which is designed to be easily moldable. The check valve 96 is included to prevent flow of cold water into the hot side when the hot water is turned full on in the system, or the equivalent usage of hot water, resulting in a lowered pressure on the hot side. The cartridge 74 can be held down in cavity 76 by a brass ring, or the like, which is in turn held down by the screw-on bonnet, which also captures the existing ball valving assembly 64 .
Another example of a single handle water control fixture is shown as 110 in FIG. 11 . This fixture 110 is a modified Moen shower valve that comprises a rear housing 112 attached to the rear 114 of Moen housing 116 . Housing 116 has a hot water inlet port 118 and a cold water inlet port 120 for receiving hot and cold water, respectively, from the hot 20 and cold 16 water lines and a valve cavity 122 for receiving the operating valve (not shown) through valve opening 124 . The operating valve controls the flow of hot and cold water out of the spout associated with valve 110 . Rear housing 112 has a cavity 126 configured to hold cartridge 127 and hot 128 and cold 130 water channels to allow passage of water around valve cavity 126 until the hot water reaches the desired temperature to cause actuator 38 to push piston 44 rearward until poppet 42 engages valve seat 90 to shut-off hot water flow through hot water channel 128 , thereby ending the diversion of “hot” water to the cold water channel 130 . Elastomeric washer shaped diaphragm 125 acts as a check valve to prevent back flow of cold to hot when hot water line pressure is reduced. Conical washer shaped screens 129 filers detritus and other trash from passing water. Screens 129 are self-cleaning due to the high water velocities encountered when the shower valve is running hot water.
Example 2
Single Handle Faucets w/Bypass Valve in Moveable Valving
This family of valves may utilize either a moveable perforated hollow spherical ball 64 , as shown in FIGS. 3 and 4 , or an internally moveable valve cartridge, that have a common internal flow area to selectively and adjustably connect the hot 20 and cold 16 lines to the discharge spout 70 . It is possible to place the same thermal valve system 36 (in a more compact form) inside of a replacement one inch diameter ball 134 for the moveable ball type or inside the replaceable faucet cartridges with internally moveable valving parts.
The previous simple hollow sphere, now 134 (shown in FIGS. 12 , 13 and 14 ), is structurally divided into two separate compartments inside ball body 135 , an outer annular compartment 136 , coaxial with the centerline of the actuating stem 138 , and a cylindrical inner compartment 140 , also coaxial with the centerline of the actuating stem 138 . Passage 162 , connected to annulus 159 , and passage 164 , connected to central bore 157 , are separated by the valving action of the bypass valve 36 installed in compartment 140 . Ball 134 is made in two parts, an upper half 142 and a lower half 144 (relative to the stem 138 which normally extends upward), which screw together for convenience in development work. The thermal actuator 88 is enclosed in the inner compartment 140 is the same as the actuator discussed above, but with a shortened guide length and a cut-off piston 44 with no poppet. The radially squeezed O-ring 146 seals the two halves 142 and 144 of ball 134 , and is held in place by the spring 148 , which also functions as the bias or return spring. The piston 44 is cut off short to conserve space, and bears on the upper end of drilled hole 150 . Unlike the above-mentioned actuators, this piston 44 remains stationary and it's the thermal actuator body 48 that moves against spring 148 to push the elastomer poppet disc 152 , which doubles as a check valve, against the stationary seat 154 as the valve 134 heats up.
The two inlet ports on ball body 135 , shown as 156 for the hot water inlet port and 158 for the cold water inlet port on FIGS. 13 and 14 , selectively and adjustably communicate with the hot 20 and cold 16 lines. The ball discharge port 160 communicates in all ball positions with the faucet spout to discharge water from faucet 10 . Ports 156 , 158 and 160 are located in exactly the same locations on the ball body 135 as the prior art ball 64 previously. However all three ports are connected within the ball to annular compartment 136 instead of to the entire inner volume of the hollow prior art ball 64 . In the shut-off mode, the hot and cold inlet ball ports 156 and 158 , respectively, of ball 134 are shifted away from the hot 20 and cold 16 lines, as with prior art ball 64 . However, ball 134 includes two added small ports 162 and 164 to the un-perforated spherical surface that previously blocked off the hot 20 and cold 16 lines. Ports 162 and 164 connect the hot 20 and cold 16 lines to the central bore 157 and annulus 159 , which are valved by action of poppet disc 152 . When the ball 134 is cold due to a cooled-off hot water line 20 , the bypass valve 36 opens, allowing communication between the annulus 159 and central bore 157 . With the faucet 10 in the shut-off position, the two added ports 162 and 164 thus allow communication between a cooled-off “hot” line 20 and the cold line 16 , and consequently a flow of water from the boosted “hot” line 20 to the cold line 16 . Positioning slot 165 in ball 134 , also in ball 64 , is used to position ball 134 in the faucet. The bypass action described above is accomplished without change to any part of the faucet 10 except the replaceable valving ball 134 . It is thus very easy to retrofit an existing faucet to the bypass function by simply replacing the existing “standard” design hollow ball 64 with the new ball 134 , as described.
There are several major advantages to this arrangement. These advantages include: (1) the complete ball 134 is easily replaced to fix a malfunctioning bypass valve 36 ; (2) for retrofit, the original ball 64 can be removed and replaced with the new valve-in-ball 134 . No other changes need be made to the existing faucet 10 (however, a booster pump 26 located near the hot water heater 18 in the hot water line 20 does of course need to be installed). This is particularly advantageous where it would be very difficult or impractical to replace an existing complete faucet valve, such as a shower valve installed behind a tiled wall.
While the hollow ball 64 of the Delta faucet (and other clone faucets) provides an adequate space in a convenient location for installation of the bypass valve 36 , a miniaturized version of the bypass valve 36 can also be fitted into the replaceable cylindrical valving cartridges of other brands of single handle faucets with an action characterized by oscillating movement about a vertical centerline to adjust water temperature. Such a valving action to control mixing is commonly used in Price-Pfister, Sterling, American Standard, Moen, and Kohler faucets, among others. These faucets use a push-pull or tipping lever action to operate the on-off function within the same (usually) cylindrical cartridge. On some configurations, it is likely that space would have to be made by lengthening these cylindrical faucet cartridges, which would in turn call for a compensating change to the faucet central housing.
FIG. 15 shows a modification of a widely used Moen designed faucet 200 as an example of a fixture that utilizes a replaceable cylindrical valving cartridge 202 . The modifications to the faucet 200 include adding a hot water bypass valve 36 within the moving valving spool 204 of the Moen design. This valve design is of the type wherein on/off and metering adjustment is accomplished by axial motion of the center spool 204 (off is all the way inward). Hot/cold mixing adjustment is by angular positioning of the center spool 204 when it is wholly or partially pulled out to the on position. The faucet 200 typically has a brass housing 206 connected to the cold water inlet 208 and hot water inlet 210 . A spout connection 212 allows water to exit the fixture 200 . FIG. 15 shows the spool 204 in its outward or “full on” position (slot 214 axially aligns with spout port 212 and slot 216 axially aligns with cold 208 and hot 210 inlet ports) and angularly rotated so that the hot port 210 is open to slot 216 but cold port 208 is blocked off.
In the position shown in FIG. 15 , hot water from port 210 can enter through slot 216 to the interior of tubular spool 204 and proceed through hollow shuttle 218 to slot 214 and exit out spout port 212 . Arrows 220 indicate the length of travel of the spool 204 . Tubular member 222 is a stationary (preexisting) sleeve incorporated within the housing 206 to allow placement and retention of the three elastomer seals 224 to bear against and dynamically seal with spool 204 . It also provides a vent path around its exterior for the space at the “bottom” of the valve 200 to allow axial (piston) motion of spool 204 without encountering hydraulic lock. Spool 204 is shown in a simplified one-piece configuration for clarity.
The bypass valve 36 components (consisting of bias spring 226 , shuttle 218 , actuator piston 228 and actuator 230 ) are enclosed within the tubular portion of spool 204 . Shuttle 218 is located (floats) between bias spring 226 and actuator 230 . Shuttle 218 has a central cruciform shaped member with an integral elastomer sleeve 232 attached to the four legs of the cruciform. Four axial passages within the sleeve 232 and around the cruciform are thus provided. This elastomer sleeve 232 is in contact with and seals against the inner surface of tubular spool 204 . When thermal actuator 230 is heated to its actuation temperature, it “suddenly” extends piston 228 outward, moving shuttle 218 (to the left in FIG. 15 ) against bias spring 226 .
Two bleed holes 234 and 236 are so located through the wall of tubular spool 204 as to line up with hot water inlet 210 and cold water inlet 208 , respectively, when the manually operated spool 204 is pushed all the way into housing 206 (the off position). Further, bleed hole 236 is axially located slightly closer to the bias spring end of spool 204 . O-rings 238 seal spool 204 and retaining clip 240 holds sleeve 222 within housing 206 .
In FIG. 15 , the bypass valve 36 components are shown in their “cold” positions. Hot bleed hole 234 is covered by the end of the elastomer sleeve 232 on shuttle 218 , but cold bleed hole 236 is uncovered. With spool 204 pushed all the way in (off position) bleed hole 234 communicates with hot water inlet 210 and boosted hot water pressure communicates through hot bleed hole 234 . this pressure deflects elastomer sleeve 232 inward locally to allow flow from the boosted hot water line 20 (presumably cooled off from a period of disuse) into the interior of tubular spool 204 and out through uncovered cold bleed hole 236 , which by virtue of the spool 204 being in the off position is in communication with cold water inlet 208 . A bypass of cooled off water from the hot water line 20 to the cold water line 16 is thus accomplished.
When sufficient cooled off water has passed through the valve 200 to bring “hot” water to and through the valve 200 , actuator 230 will be warmed to its actuation temperature and will expand, forcing shuttle 218 against bias spring 226 . This axial movement will result in elastomer sleeve 232 covering cold bleed hole 236 . Boosted hot water pressure internal to sleeve 232 will hold sleeve 232 outward against the inner wall of tubular spool 204 , effectively sealing bleed hole 236 , and stopping the bypass flow until the valve cools down, causing bias spring 226 to force shuttle 218 back against piston 10 into contracting actuator 230 , again opening cold bleed hole 236 .
The elastomer sleeve 232 has a second function, that of acting as a check valve. When any faucet in the plumbing system is opened, the resulting flow may induce a substantial pressure drop in the associated plumbing line (either hot 20 or cold 16 , depending on which faucet was opened). If a bypass valve 36 is open at such a time, such a pressure difference may cause sufficient water to leak through so as to constitute a nuisance. If the lowered pressure is on the hot water line 20 , no “leak” will occur as the higher pressure of the cold water inside the sleeve 232 will hold it against the inner wall of tubular spool 204 in the vicinity of hot bleed hole 234 , effecting a seal. If the lowered pressure is on the cold side, the valve 200 will allow cooled off water from the hot water line 20 to bypass into the cold water line until warm water arrives at the valve 200 , at which time the shuttle 218 will shift and cut off the bypass.
Example 3
Dual Handle, Single Spout Faucets
Although two handle, single spout faucets might have been expected to fade out of demand in favor of the more convenient single handle faucets, the two handle faucets (shown as 10 in FIG. 1 ) seem more amenable to elegant cosmetic design than their single handle cousins, which have an inherently more utilitarian look. Apparently for this reason, most double handle faucets on display are for lavatory use. The same requirements for ease of maintenance by allowing access to the bypass valve 36 from the top apply to this faucet type. It is convenient that the prior art faucet design utilizing a rotating threaded stem with a faucet washer and a hard seat has become a thing of the past, as the newer designs with replaceable cartridges are more adaptable to this modification.
Most modern two handle faucets utilize a cartridge design in a pair of valve member 166 , shown in FIG. 16 , wherein the valving function is accomplished within the cartridge that is positioned inside the housing section 168 of valve member 166 . This allows complete re-conditioning of the faucet by simply replacing a single assembly on each side. These cartridges are accessible in the housing section 168 from the top by removing the faucet handles and bonnets that attach to the upper threaded portion 170 . The cartridge assembly then simply lifts out, exposing its open cavity inside housing section 168 , with a side port 172 leading to confluence with the like port from the other side of the faucet, which confluence flows on through the single spout of such faucets. Below the mentioned cavity for the faucet valving cartridge there is an open one-half inch (typically) threaded pipe 174 for the hot or cold conduit into the faucet. This externally threaded pipe is substantially longer than needed for valving or connection purposes to allow for overly thick lavatory counters and to get the lower end of these threaded pipes far enough down behind the sink for reasonable access by the installer. This “extra” space on the hot water side is a top accessible, hydraulically appropriate place to locate a thermal valve cartridge similar to the type described for inclusion in or adjacent to the hot water conduit in the central housing 62 of a single handle faucet. Side port 175 is added to housing section 168 and a line is run to a like port on the other, opposing faucet. Addition of a thermal bypass valve 36 requires additional machining and the addition of a bypass line connecting the hot and cold lines. An existing two handle single spout valve thus could not be retrofitted, but modifications to the design are relatively minor and the existing replaceable valve cartridge would fit the new design.
The major difference of concern in this matter between single handle single spout and two handle single spout faucet designs is that in the single handle central block, it is possible to create the connecting passages (bypass) by simply drilling cross holes, as discussed above. With two separate hot and cold faucet valves located four inches apart, some kind of cross conduit for the bypass must be added. There seem to be two approaches to directing the water from the hot and cold faucets to a confluence and out to the single spout. American-Standard, Oasis, La Bella and some Price-Pfisters use a large brass casting that includes the spout, both hot and cold faucet housings, and a cored cast passage connecting all of this together. Adding a thermal bypass valve 36 to such a two handle faucet set would require the addition of an additional cored cast passage to accomplish the bypass function between hot and cold lines. Delta, Moen, Kohler, and some Price Pfister two handle single spout valves use brazed-in copper tube manifolds instead of cored cast passages. These would require the addition of a tubular cross passage brazed in. The Delta two handle single spout valve has a somewhat different valving action which makes it much more difficult to fit in a thermal valve cartridge. This new passage (cored or brazed tubular) needs to connect to the vertical hot and cold “pipe” members below their existing side port to the spout. These faucet sets generally do not have sufficient vertical space under the polished bezel to accommodate the extra passage. This will require addition of some vertical length to the skirt of the valve bezel.
FIG. 17 shows a modified “hot” side of a Kohler two handle faucet 176 , with the housing shown as 178 . The housing 178 is identical to the standard existing Kohler housing 178 above (to the right of) line AA. The housing 178 must be bored out in several steps to accommodate the new thermal valve cartridge 180 , which can be a molded plastic cartridge identical in function to that already described for the center block of the Delta single handle valve. It varies from the previously described cartridge in the configuration of the passage to bring the hot water past the thermal valve 36 to the faucet, and the configuration of the snap fit for the thermal actuator 88 . It also has an upper extension 182 with a through hole 184 . The extension 182 fits into a recess in the bottom of the existing Kohler faucet cartridge and the through hole 184 is for engagement of a hook to allow removal of the thermal valve cartridge 180 for replacement of the thermal bypass valve 36 .
The operation of the bypass valve 36 inside of faucet 10 of the present invention is summarized on the chart shown as FIG. 18 which indicates the results of the twenty combinations of conditions (pump on/pump off; hot water line hot/hot water line cooled off; hot faucet on, or off, or between; cold faucet on or off, or between) that are applicable to the operation of valve 36 . The operating modes IVB, IVC, IVD, IIIB, & IIID are summarized detailed in the immediately following text. The operation of the remaining fifteen modes are relatively more obvious, and may be understood from the abbreviated indications in the outline summarizing FIG. 18 . Starting with the set “off” hours (normal sleeping time, and daytime when no one is usually at home) pump 26 will not be powered. Everything will be just as if there were no pump 26 and no bypass valve 36 installed in faucet 10 (i.e., both the cold and hot water lines will be at the same city water pressure). The hot water line 20 and bypass valve 36 will have cooled off during the long interim since the last use of hot water. The reduced temperature in the valve results in “retraction” of rod member 40 of the thermally sensitive actuator 88 . The force of bias spring 106 pushing against flange 46 on rod member 40 will push it back away from valve seat 90 , opening valve 36 for recirculation. Although the thermal actuating element 88 is open, with pump 26 not running, no circulation flow results, as the hot 20 and cold 16 water piping systems are at the same pressure. This is the mode indicated as IVB in the outline on FIG. 18 . If the cold water valve at faucet 10 is opened with the thermal element 88 open as in mode IVB above, pressure in the line 16 to the cold water side of faucet 10 will drop below the pressure in the hot water line 20 . This differential pressure will siphon tepid water away from the hot side to the cold side, which is the mode indicated as IVD in the outline on FIG. 18 . The recirculation of the “hot” water will end when the tepid water is exhausted from the hot water line 20 and the rising temperature of the incoming “hot” water causes the thermal element 88 to close.
If the hot water valve is turned on with the thermal element 88 open as in mode IVB above, pressure in the line 20 to the hot water side of faucet 10 will drop below the pressure in the cold water line 16 . This differential pressure, higher on the cold side, will load check valve 96 in the “closed” direction allowing no cross flow. This is mode IVC in the outline on FIG. 18 . In this mode, with the hot water line 20 cooled and the pump off, a good deal of cooled-off water will have to be run (just as if valve 36 were not installed), to get hot water, at which time the thermal element 88 will close without effect, and without notice by the user. With the thermal element 88 open and the hot water line 20 cooled-off as in mode IVB above, at the preset time of day (or when the cyclic timer trips the next “on” cycle) the pump 26 turns on, pressurizing the water in the hot side of faucet 10 . Pump pressure on the hot side of faucet 10 results in flow through the open thermal element 88 , thereby pressurizing and deflecting the check valve 96 poppet away from its seat to an open position. Cooled-off water at the boosted pressure will thus circulate from the hot line 20 through the thermal element 88 and check valve 96 to the lower pressure cold line 16 and back to water heater 18 . This is the primary “working mode” of the bypass valve 36 and is the mode indicated as IIIb in the outline on FIG. 18 . If the cold water valve is turned on during the conditions indicated in mode IIIB above (i.e., pump 26 operating, hot line 20 cooled off, the hot valve at faucet 10 off) and while the desired recirculation is occurring, mode IIID will occur. A pressure drop in the cold water line 16 due to cold water flow creates a pressure differential across valve 36 in addition to the differential created by pump 26 . This allows tepid water to more rapidly bypass to the cold water inlet 22 at faucet 10 . When the tepid water is exhausted from the hot water line 20 , thermal element 88 will close, ending recirculation.
Explanation of FIG. 18 Table
MODE 1: Water In Hot Water Supply Line Hot, Pump On.
A. Hot and cold faucet valves full open
Pressure drops from hot and cold flow about equal. Actuator element 26 stays closed. No leak or recirculation in either direction.
B. Hot and cold faucet valves fully closed
Thermal actuator 88 keeps valve 36 closed. No recirculation.
C. Hot faucet valve fully open, cold faucet valve closed
Actuator element 88 closed. Check valve 96 closed. No recirculation. No leak.
D. Hot faucet valve closed, cold faucet valve fully open
Actuator element 88 closed. No recirculation. No leak.
E. Hot and cold faucet valves both partially open in any combination
Actuator element 88 closed. No recirculation. No leak.
MODE II: Water in Hot Water Supply Line Hot, Pump Off.
A. Hot and cold faucet valves full on
Pressure drops from hot and cold flow about equal. Actuator element 88 stays closed.
B. Hot and cold faucet valves fully closed
Thermal actuator 88 keeps valve 36 closed. No recirculation.
C. Hot faucet valve fully open, cold faucet valve closed
Thermal actuator 88 closed. Check valve 96 closed. No recirculation. No leak.
D. Hot faucet closed, cold faucet fully open
Thermal actuator 88 closed. No recirculation. No leak.
E. Hot and cold faucets both partially open in any combo
Thermal actuator 88 closed. No recirculation. No leak.
MODE III: Water in Hot Water Line Cooled Off, Pump On.
A. Hot and cold faucet valves full open
Flow-induced pressure drops about equal, valve 36 stays open and allows recirculation hot to cold until tepid water is exhausted and hotter water closes thermal actuator 88 . If both faucet valves are at same sink, they are mixing hot and cold anyway. If faucet valves being manipulated are at remote sinks on the same plumbing branch, this short time tepid-to-cold leak will probably not be noticeable. If faucet valves being manipulated are on remote branches of plumbing, the mixing would have no effect.
B. Hot and cold faucet valves fully closed
Thermal actuator 88 open, get desired tepid-to-cold recirculation until hot line heats up.
C. Hot faucet valve fully open, cold faucet valve closed
Thermal actuator 88 open but pressure drop in hot line may negate pump pressure, stopping recirculation. Check valve 96 stops cold to hot leak.
D. Hot faucet valve closed, cold faucet valve fully open
Thermal actuator 88 open, get tepid to cold recirculation until hot line heats up.
E. Hot and cold faucets both partially open in any combination
Could get tepid to cold leak. If faucet valves at same sink don't care as mixing hot and cold anyway. If at remote sinks probably not noticeable. Tepid to cold leak would be short term.
MODE IV: Water In Hot Water Supply Line Cooled Off, Pump Off.
A. Hot and cold faucet valves full open
Flow-induced pressure drops about equal, valve 36 stays open and may allow recirculation (leak) hot to cold until tepid water is exhausted and hotter water a long shallow groove 190 in or a reduced diameter of piston 44 that would extend from just inside the guide bore 186 (at full extension) to just outside the guide bore 186 at full retraction would provide a recess to contain buildup for a long period. Once this recessed area filled up with lime, the edge 188 of guide bore 186 could scrape off the incrementally radially extending soft build up relatively easily, as compared to scraping off the surface layer that bonds more tenaciously to the metal.
The most direct method to overcome sticking due to mineral buildup is to optimize actuator force in both directions. Buildup of precipitated minerals on the exposed outside diameter of the extended piston 44 tends to prevent retraction, requiring a strong bias spring 106 . This high bias spring force subtracts from the available extending force however, thereby limiting the force available to both extend the piston 44 against the mineral sticking resistance and to effect an axial seal between poppet and seat.
When water temperature is high, the piston 44 is extended so that its surface is exposed. Deposition also occurs primarily at high temperatures, so that buildup occurs on the piston outside diameter, resulting in sticking in the extended position when the growth on the piston outside diameter exceeds the guide 186 interior diameter. Significantly more than half of the available actuator force thus can most effectively be used to compress the bias spring 106 , resulting in a maximum return force.
While there is shown and described herein certain specific alternative forms of the invention, it will be readily apparent to those skilled in the art that the invention is not so limited, but is susceptible to various modifications and rearrangements in design and materials without departing from the spirit and scope of the invention. In particular, it should be noted that the present invention is subject to modification with regard to the dimensional relationships set forth herein and modifications in assembly, materials, size, shape, and use. While the invention has been described in terms of various specific embodiments, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope.
It is to be understood that the above description is intended to be illustrative, and not restrictive. For example, the above-described embodiments (and/or aspects thereof) may be used in combination with each other. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from its scope. Dimensions, types of materials, orientations of the various components, and the number and positions of the various components described herein are intended to define parameters of certain embodiments, and are by no means limiting and are merely exemplary embodiments. Many other embodiments and modifications within the spirit and scope of the claims will be apparent to those of skill in the art upon reviewing the above description. The scope of the invention should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. In the appended claims, the terms “including” and “in which” are used as the plain-English equivalents of the respective terms “comprising” and “wherein.” Moreover, in the following claims, the terms “first,” “second,” and “third,” etc. are used merely as labels, and are not intended to impose numerical requirements on their objects. Further, the limitations of the following claims are not written in means—plus-function format and are not intended to be interpreted based on 35 U.S.C. §112, sixth paragraph, unless and until such claim limitations expressly use the phrase “means for” followed by a statement of function void of further structure. | A water control fixture includes a fixture body in fluid communication with a pressurized supply of hot water and a pressurized supply of cold water. The fixture body interconnects the supply of hot water and the supply of cold water. The fixture body has a spout outlet configured to dispense water from the fixture body. At least one operating valve is coupled to the fixture body for controlling a flow of water to the spout outlet. A bypass valve is disposed in the fixture body for controlling a recirculating flow of water through the fixture body. The bypass valve blocks and permits recirculating flow from the supply of hot water to the supply of cold water based on a temperature of the water. | 8 |
TECHNICAL FIELD
[0001] The present invention relates generally to vehicle fuel systems. More specifically, the present invention relates to a fuel pipe having a trigger point which allows the fuel pipe to buckle if there is a structural disruption of the vehicle, thus reducing or entirely eliminating the amount of displacement of the fuel filler pipe into the fuel tank during the structural disruption.
BACKGROUND OF THE INVENTION
[0002] In the modern motor vehicle fuel is delivered to the fuel tank by a fuel filler pipe. The fuel filler pipe creates a fluid connection between the fuel supply port disposed within the fuel filler housing and the fuel tank. Fuel filler pipes are made of a metal or a synthetic resin. Those fuel filler pipes composed of metal are typically composed of stainless steel, aluminum, or steel.
[0003] Fuel systems in motor vehicles, including the fuel filler pipe, must meet certain safety standards. In seeking to surpass known standards, motor vehicle manufacturers attempt to improve the integrity of their vehicle fuel system designs. One sought-after improvement has to do with the fuel filler pipe of the fuel system and how it reacts in the event of a structural disruption of the vehicle. Accordingly, as in so many areas of motor vehicle technology, there is room in the art of motor vehicle fuel systems for providing an alternative configuration to known fuel filler pipe designs.
SUMMARY OF THE INVENTION
[0004] The present invention provides an alternative configuration for a fuel filler pipe which includes an area of reduced cross-section relative to the rest of the fuel filler pipe which defines a crumple area or a trigger point in the fuel filler pipe. The trigger point formed in an appropriate location facilitates a buckling mode in the pipe in the event that there is a structural disruption of the vehicle and consequent energy absorption. By providing the trigger point in an appropriate place in the fuel filler pipe, during such a disruption the amount of possible displacement or intrusion of the pipe into the fuel tank is reduced or eliminated.
[0005] With the trigger point provided at an appropriate location on the fuel filler pipe with an appropriate geometry, an alternative construction of the current fuel filler pipe is provided.
[0006] Other advantages and features of the invention will become apparent when viewed in light of the detailed description of the preferred embodiment when taken in conjunction with the attached drawings and the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] For a more complete understanding of this invention, reference should now be made to the embodiment illustrated in greater detail in the accompanying drawings and described below by way of examples of the invention wherein:
[0008] FIG. 1 shows an elevation view of a fuel filler pipe in relation to a fuel tank, partially broken away, according to the prior art;
[0009] FIG. 2 shows an elevation view of a fuel filler pipe in relation to a fuel tank, partially broken away, according to the present invention;
[0010] FIG. 3 shows a close-up view of the trigger point of the fuel pipe of the present invention;
[0011] FIG. 4 is a cross section of the trigger point of the fuel filler pipe according to the present invention taken along lines 4 - 4 of FIG. 3 ; and
[0012] FIG. 5 shows the fuel filler pipe and fuel tank of FIG. 2 after a structural disruption of the vehicle with the filler pipe in a buckled condition.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0013] In the following figures, the same reference numerals will be used to refer to the same components. In the following description, various operating parameters and components are described for one constructed embodiment. These specific parameters and components are included as examples and are not meant to be limiting.
[0014] With reference to FIG. 1 , a fuel delivery assembly according to known technology, generally illustrated as 10 . The fuel delivery assembly 10 includes a fuel tank 12 , a fuel filler port 14 , and a fuel filler pipe 16 connected to a fuel tank inlet pipe 18 . An air vent tube 20 is provided in fluid relation to the fuel filler port 14 . As is known in the art, the fuel filler pipe 16 is of a constant diameter between the fuel filler port 14 and the fuel tank pipe 18 .
[0015] With reference to FIGS. 2 through 4 , a fuel delivery assembly according to the present invention, generally illustrated as 30 , is shown. The fuel delivery assembly 30 includes a fuel tank 32 , a fuel filler port 34 , and a fuel filler pipe 36 connected to a fuel tank inlet pipe 38 . In addition, an air vent tube 40 is provided in fluid relation to the fuel filler port 34 as is conventionally provided.
[0016] The diameter of the fuel filler pipe 36 from its inlet end at the fuel filler port 34 to its outlet end at the fuel tank inlet pipe 38 is relatively constant with the exception of an area of reduced cross-section which defines a crumple area or a trigger point 42 which is located on a bend of the fuel filler pipe 36 . The trigger point 42 defines a trough-like depression and may be formed by any one of several known methods, including formation by a punch or by stamping. The thickness of the wall of the fuel filler pipe 36 at the trigger point 42 may be the same as the thickness of the other areas of the wall of the fuel filler pipe 36 or may be of reduced thickness to allow for more effective buckling if there is a structural disruption of the vehicle.
[0017] The trigger point 42 is preferably formed at the bend of the fuel filler pipe 36 as illustrated to increase the tendency of this area to form a plastic hinge upon loading.
[0018] Correct placement and geometry of the trigger point 42 relative to the fuel filler pipe 36 are factors that need to be carefully considered. As illustrated particularly in FIG. 2 , the trigger point 42 is disposed at the bent area of the fuel filler pipe 36 that is formed roughly half-way between the fuel filler port 34 and the fuel tank inlet pipe 38 . According to such placement, if there is a structural disruption of the vehicle the trigger point 42 facilitates a buckling mode and consequently absorbs energy that would otherwise cause displacement or intrusion of the fuel tank inlet pipe 38 into the fuel tank 32 .
[0019] While the trigger point 42 is illustrated as being at the approximate mid-point of the fuel filler pipe 36 between the fuel filler port 34 and the fuel tank inlet pipe 38 , the trigger point 42 may be formed at an alternative point on the fuel filler pipe 36 or there may be two or more trigger points fitted on the fuel filler pipe 36 .
[0020] A cross-sectional view of the fuel filler pipe 36 at the trigger point 42 is illustrated in FIG. 4 . A certain percentage of the circumference of the filler pipe 36 is encompassed by the trigger point 42 . As illustrated, about 20 percent of the circumference of the filler pipe 36 is encompassed by the trigger point 42 . However, it is to be understood that a greater or lesser percentage of the circumference of the filler pipe 36 may be encompassed by the trigger point 42 without deviating from the scope of the present invention. Preferably the trigger point 42 will encompass between about 10 and 30 percent of the circumference of the filler pipe 36 . In any event, it is preferable that the trigger point 42 not be axisymmetric to avoid the backflow of fuel which might otherwise result.
[0021] The possible result of a structural disruption of the vehicle is illustrated in FIG. 5 where the impact force has been transmitted to the trigger point 42 which has absorbed the energy from the impact force that caused the structural disruption of the vehicle and has allowed a slight angular deformation or buckling of the fuel filler pipe 36 at the trigger point 42 . Intrusion of the fuel tank inlet pipe 38 has thus been avoided and, in addition, no rupturing of the connection between the fuel tank inlet pipe 38 and the fuel tank 32 has occurred, virtually eliminating the possibility of fuel spillage.
[0022] The foregoing discussion discloses and describes an exemplary embodiment of the present invention. One skilled in the art will readily recognize from such discussion, and from the accompanying drawings and claims that various changes, modifications and variations can be made therein without departing from the true spirit and fair scope of the invention as defined by the following claims. | A fuel filler pipe having a trigger point formed between the fuel supply port and the fuel tank. The trigger point is a trough-like depression which, if there is a structural disruption of the vehicle, will facilitate a buckling mode in the pipe and consequent energy absorption. This configuration reduces or eliminates the amount of displacement of the fuel filler pipe into the fuel tank during such structural disruption of the vehicle. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a ceramic substrate whereon semiconductor devices, LSIs and component chips are mounted, and a method to manufacture thereof.
2. Description of the Related Art
A Ceramic chip carrier substrate of the prior art has a plurality of external connection pads on each of the four side faces thereof. These external connection pads are formed to extend from the side face to the bottom of the substrate. Recently, ceramic substrates having bumps arranged in a grid configuration on the bottom face for external connection have been put into use. Such ceramic chip carriers can be mounted in high density on a printed circuit board.
Ceramic chip carriers are mounted on a printed circuit board (mother board) in such a procedure as described below. Solder paste is printed onto specified terminals provided on a printed circuit board. Ceramic chip carriers are arranged on the printed circuit board so that the external connection terminals provided on the bottom face of the ceramic chip carrier are placed on the terminals with the solder paste printed thereon. Then the solder is reflowed so that the external connection terminals provided on the bottom face of the ceramic chip carrier are soldered onto the specified terminals provided on the printed circuit board.
External connection bumps of the conventional ceramic chip carrier have been formed after the manufacture of the ceramic substrate. This procedure results in a problem of high manufacturing cost of the ceramic chip carrier. Also in the procedure of forming each of the plurality of external connection bumps one by one, there has been a problem of variations being caused in the height, size and configuration of the external connection bumps. Deviation in the height of the external connection bumps is likely to cause connection failure between bumps of smaller height and the printed circuit board.
Moreover, there has been no method available to form the external connection bumps having sufficient height. As a result, there has been a problem in that the substrate of the ceramic chip carrier and the printed circuit board are brought too close to each other, causing solder bridges in the solder reflowing process which result in short-circuiting between the electrodes. There also has been a problem of joints being broken due to thermal stress, when the ceramic chip carrier substrate and the printed circuit board whereon the ceramic chip carriers are mounted have different thermal expansion coefficients.
As a solution to the problem of solder bridge, the Japanese Laid-Open Patent Publication No. 61-188942 discloses a method of preventing the solder bridge by providing a blocking means made of an electrically insulating material around the soldered Joints. However, this method results in a complicated structure and a problem of high manufacturing cost.
SUMMARY OF THE INVENTION
The method of manufacturing a ceramic substrate having a plurality of bumps of the present invention, includes the steps of: forming a bump forming layer having a plurality of holes therein on at least one of upper and lower faces of a laminated body of green sheets; filling the holes in the bump forming layer with a bump forming paste; sintering the laminated body of the green sheets and the bump forming paste; and forming bumps made of the sintered bump forming paste by removing the bump forming layer.
In one embodiment of the present invention, the step of forming the bump forming layer includes the steps of: making the plurality of holes in at least one green sheet for bump forming layer; and applying the at least one green sheet for bump forming layer onto the at least one face of the laminated body of green sheets.
In another embodiment of the present invention, the above-mentioned method includes, before the sintering step, the steps of: applying heat treatment to the laminated body of green sheets and the bump forming paste in order to remove organic substances included in the laminated body of green sheets and the bump forming paste; and reducing the bump forming paste.
In another embodiment of the present invention, the green sheet for bump forming layer includes inorganic components as major components, which are not sintered at the sintering temperature of the sintering step.
In another embodiment of the present invention, the green sheet for bump forming layer includes at least one component selected from a group consisting of Al 2 O 3 , MgO, ZrO 2 , TiO 2 , BeO and BN.
In another embodiment of the present invention, the step of forming the bump forming layer includes the step of: printing the bump forming layer having the plurality of holes therein on the at least one face of the laminated body of green sheets by using a paste for bump forming layer.
In another embodiment of the present invention, the method further includes, before the sintering step, the steps of: applying heat treatment to the laminated body of green sheets, the bump forming paste and the paste for bump forming layer in order to remove organic substances included in the laminated body of green sheets, the bump forming paste and the paste for bump forming layer; and reducing the bump forming paste.
In another embodiment of the present invention, the method further includes, before the step of forming the bump forming layer, the step of forming a substrate forming layer on at least one face of the laminated body of green sheets by printing a paste for forming substrate.
In another embodiment of the present invention, the paste for bump forming layer includes inorganic components as major components, which are not sintered at the sintering temperature of the sintering step.
In another embodiment of the present invention, the paste for bump forming layer includes at least one component selected from a group consisting of Al 2 O 3 , MgO, ZrO 2 , TiO 2 , BeO and BN.
In another embodiment of the present invention, the bump forming paste is a conductive paste including at least one component selected from a group consisting of Ag, Pd, Pt and Cu.
In another embodiment of the present invention, the bump forming paste is a metal oxide paste including CuO as the major component.
In another embodiment of the present invention, the plurality of bumps each have a form of a pillar.
In another embodiment of the present invention, the method of manufacturing a ceramic substrate having a plurality of bumps includes the steps of: forming a bump forming layer having a plurality of holes therein on at least one of upper and lower faces of a ceramic substrate; filling the holes in the bump forming layer with a bump forming paste; sintering the laminated body of the green sheets and the bump forming paste; and forming bumps made of the sintered bump forming paste by removing the bump forming layer.
In another embodiment of the present invention, the step of forming the bump forming layer includes the steps of: making the plurality of holes in at least one green sheet for bump forming layer; and applying the at least one green sheet for bump forming layer onto the at least one face of the ceramic substrate.
In another embodiment of the present invention, the method further includes, before the sintering step, the steps of: applying heat treatment to the green sheet for bump forming layer and the bump forming paste in order to remove organic substances included in the green sheets for bump forming layer and the bump forming paste; and reducing the bump forming paste.
In another embodiment of the present invention, the green sheet for bump forming layer includes inorganic components as major components, which are not sintered at the sintering temperature of the sintering step.
In another embodiment of the present invention, the green sheet for bump forming layer includes at least one component selected from a group consisting of Al 2 O 3 , MgO, ZrO 2 , TiO 2 , BeO and BN.
In another embodiment of the present invention, wherein the step of forming the bump forming layer comprises the step of: printing the bump forming layer having the plurality of holes therein on the at least one face of the ceramic substrate by using a paste for bump forming layer.
In another embodiment of the present invention, the method further includes, before the sintering step, the steps of: applying heat treatment to the bump forming paste and the paste for bump forming layer in order to remove organic substances included in the bump forming paste and the paste for bump forming layer; and reducing the bump forming paste.
In another embodiment of the present invention, the method further includes, before the step of forming the bump forming layer, the step of forming a substrate forming layer on at least one face of the ceramic substrate by printing a paste for forming substrate.
In another embodiment of the present invention, the paste for bump forming layer includes inorganic components as major components, which are not sintered at the sintering temperature of the sintering step.
In another embodiment of the present invention, the paste for bump forming layer includes at least one component selected from a group consisting of Al 2 O 3 , MgO, ZrO 2 , TiO 2 , BeO and BN.
In another embodiment of the present invention, the bump forming paste is a conductive paste including at least one component selected from a group consisting of Ag, Pd, Pt and Cu.
In another embodiment of the present invention, the bump forming paste is a metal oxide paste including CuO as the major component.
In another embodiment of the present invention, the plurality of bumps each have a form of a pillar.
In another aspect of the present invention, the ceramic substrate has a plurality of bumps made of a sintered body of a bump forming paste.
In another embodiment of the present invention, the plurality of bumps each have a form of a pillar.
Thus, the invention described herein makes possible the advantages of (1) providing a ceramic substrate and (2) providing a method of manufacturing a ceramic substrate, wherein the solder bridge is not likely to occur and high reliability can be obtained.
These and other advantages of the present invention will become apparent to those skilled in the art upon reading and understanding the following detailed description with reference to the accompanying figures.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view showing a back face of a ceramic substrate of Example 1 of the invention wherein an unsintered layer for the formation of bumps has been removed.
FIGS. 2a-2f is a drawing illustrative of a process in the manufacturing method for the ceramic substrate of Example 1 of the invention.
FIG. 3 is a cross sectional view of a laminated body used in the manufacture of the ceramic substrate of Example 1 of the invention.
FIG. 4 is a cross sectional view of a laminated body made by sintering the laminated body of FIG. 3 and removing alumina therefrom.
FIG. 5 is a cross sectional view of another laminated body used in the manufacture of the ceramic substrate of Example 1 of the invention.
FIG. 6 is a cross sectional view of another laminated body used in the manufacture of the ceramic substrate of Example 1 of the invention.
FIG. 7 is a cross sectional view of a laminated body after printing of alumina paste used in Example 2 of the invention.
FIG. 8 is a cross sectional view of a ceramic substrate, having protruding electrodes made of an electrically conductive material, being mounted on a printed circuit board in Example 5 of the invention.
FIG. 9 is a view showing the back face of a ceramic substrate of Example 5 of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention wall be described by way of example with reference to the accompanying drawings as follows:
EXAMPLE 1
FIG. 1 shows a view of a substrate having external connection bumps obtained in this example viewed from a perspective view from the bottom. The ceramic substrate of the invention has external connection bumps 1 which have sufficient height and are uniform in the height, configuration and size, being provided on the bottom of the substrate 2.
A method of manufacturing the ceramic substrate of the invention will first be described. While the invention wall be described taking a substrate sintered at a low temperature as an example in the following embodiments, although the invention is not limited to this scheme.
A mixture of borosilicate-lead glass powder and alumina powder as the ceramic material being mixed in a 50:50 weight ratio (MLS-19 manufactured by Nippon Electric Glass Co., Ltd.) was used for the glass-ceramic material to make the substrate. Using this glass-ceramic powder as the inorganic material, polyvinyl butyral as the organic binder, di-n-butyl phthalate as a plasticizer and toluene and isopropyl alcohol being mixed in a weight ratio of 30:70 as the solvent, a slurry was made by mixing these substances together.
The slurry was applied on an organic film to form it into a sheet by means of a doctor blade method. As an organic film, a polymer film such as PET film can be used. The organic film with the slurry being spread thereon was dried and punched into the desired size in order to obtain green sheets for the forming of substrates. Via-holes were formed as required in the substrate forming green sheet. The processes of forming the film, drying the film and making via-holes were carried out by using equipment known to those skilled in the art which performs these processes continuously.
The processes will be described below with reference to FIGS. 2a-2f. FIGS. 2a-2f is a drawing illustrative of the process of manufacturing the ceramic substrate of the invention. Holes are formed in a green sheet for bump forming layer and in a substrate forming green sheet (FIG. 2a). The holes are filled using a squeegee 17 and a metal plate 18 (FIG. 2b). Wiring patterns are printed (FIG. 2c). The layers are laminated (FIG. 2d) and then sintered (FIG. e). Finally, the bump forming layer is removed (FIG. 2f). A screen printing process was employed in the printing for the formation of the substrate forming green sheet and via-hole filling in the substrate forming green sheet by using Ag paste as the conductive paste. As an inorganic component of the wiring forming Ag paste, Ag powder (mean particle size 1 μm) with 5 wt % of glass frit (GA-9 glass powder with a mean particle size of 2.5 μm, made by Nippon Electric Glass Co., Ltd.) being added thereto in order to increase the bonding strength was used. By adding PVB as the organic binder and a vehicle dissolved in terpineol to the inorganic component and mixing these materials by means of a 3-step roll, the wiring forming paste with proper viscosity was obtained. The via-hole filling Ag paste was prepared by further adding 15 wt % of the glass ceramic powder as the inorganic component to the wiring forming paste. The via-hole filing Ag paste was used as a bump forming paste.
Now the method of manufacturing the green sheet for bump forming layer will be described below. Using alumina powder (ALM-41 with a mean particle size of 1.9 μm, made by Sumitomo Chemical Co., Ltd.) as the inorganic material, with ethyl cellulose being added as the organic binder together with a vehicle dissolved in terpineol, and turned into a slurry in order to prepare the green sheet which will not be sintered for the forming of bumps. The slurry was applied onto an organic film so as to form it into a sheet by means of the doctor blade method. Holes for forming the bumps were made in the thus obtained green sheet in order to make a green sheet for forming bumps. Similarly to the case of the substrate forming green sheet, the holes made in the green sheet for bump forming layer were filled with the via-hole filling Ag paste.
Specified numbers of the substrate forming green sheets and the bump forming green sheets were placed one on another so that the green sheet for bump forming layer became the outermost layer, and were bonded by thermo-compression bonding so as to make a laminated body. Conditions of thermo-compression bonding were a temperature of 80° C. and a pressure of 200 kg/cm 2 . The substrate forming green sheet and the green sheet for bump forming layer were about 200 μm thick. FIG. 3 shows the structure of the laminated body thus obtained in a cross sectional view. The laminated body comprises the substrate forming green sheet layer 3 having a wiring pattern 5 and the green sheet for bump forming layer 4 having bump electrodes 6.
Then the laminated body was placed on a substrate made of 96% alumina and was then sintered. Sintering was carried out in a belt furnace in an air atmosphere at 900° C. for one hour. The temperature of 900° C. was maintained for about 12 minutes.
The alumina layer of the green sheet for bump forming layer in the laminated body is not sintered at 900° C. Therefore, the unsintered alumina layer was completely removed by subjecting the sintered laminated body to ultrasonic cleaning in butylacetate solvent, thereby bumps were obtained. FIG. 4 shows a cross sectional view of the ceramic substrate with the alumina layer of the green sheet for bump forming layer having been removed. The ceramic substrate of this example has bump electrodes 6 for external connection being provided on the surface of the substrate 7 which has the wiring pattern 5.
While the bumps are formed on one side of the ceramic substrate in the above example, bumps may also be formed on both sides of the ceramic substrates. FIG. 5 shows a cross sectional view of a laminated body having green sheets for bump forming layer 4 on both sides of the substrate forming green sheet 7. A ceramic substrate having bumps on both sides can be obtained by sintering the laminated body shown in FIG. 5 and removing the alumina layer of the green sheet for bump forming layer.
By using a laminated body having such a structure that the substrate forming green sheet is interposed between a green sheet comprising only of alumina and a green sheet for bump forming layer, as shown in FIG. 6, deformation of the substrate such as warping can be prevented during the sintering process for forming bumps on one side of the ceramic substrate. FIG. 6 shows a cross sectional view of a laminated body used in the manufacture of the ceramic substrate obtained from this example. This laminated body has a substrate forming green sheet 3 between the green sheet for bump forming layer 4 and the green sheet 4a made of alumina only.
EXAMPLE 2
In this example, a bump forming layer was formed by using a paste for bump forming layer instead of the green sheet for bump forming layer of Example 1. First, a substrate forming green sheet was made similar to Example 1. A specified number of substrate forming green sheets whereon a wiring pattern was printed and via-holes were made were laminated and bonded by means of a thermo-compression bonding method, so as to obtain a laminated body of green sheets. Conditions of the thermo-compression bonding were a temperature of 80° C. and a pressure of 200 kg/cm 2 . The substrate forming green sheet was about 200 μm thick.
Then the paste for bump forming layer was prepared, using alumina powder (ALM-41 with a mean particle size 1.9 μm, made by Sumitomo Chemical Co., Ltd.) as the inorganic component. With ethyl cellulose being added as the organic binder together with a vehicle dissolved in terpineol being added to the alumina powder, and mixing them to obtain an appropriate viscosity (30 Pa·s) by means of a 3-step roll, the paste for bump forming layer was obtained. The paste for bump forming layer was printed in order to form a bump forming layer having a plurality of holes therein onto one side of the laminated body of the substrate forming green sheet and the paste for bump forming layer was printed in a plain pattern on the other side of the laminated body of the substrate forming green sheet. A screen of 200 mesh and an emulsion thickness 30 μm were used in the double printing of the paste for bump forming layer. The paste for bump forming layer film thus obtained was about 100 μm thick.
The laminated body whereon the paste for bump forming layer was printed, was dried at 50° C. for 10 minutes. Then the holes formed by the paste for bump forming layer were filled with a conductive paste and dried at 50° C. for 10 minutes. FIG. 7 shows a cross sectional view of the laminated body obtained in this example. The laminated body has a layer of paste for bump forming layer 8, wiring pattern 9, bump electrodes 10 and a substrate forming ceramic green sheet layer 11. A part of the laminated body with the surface thereof not covered by the alumina paste was cut off so that the resultant laminated body was covered by the alumina paste over the entire surface thereof. This operation made the structure of the laminated body symmetrical and made it possible to suppress the deformation of the laminated body during the sintering process.
Then the laminated body was sintered in a belt furnace in an air atmosphere at 900° C. for one hour in order to obtain a sintered body. The temperature of 900° C. was maintained for about 12 minutes.
The alumina which is the main component of the paste for bump forming layer on the surface of the laminated body is not sintered at 900° C. Therefore, the bump forming layer was completely removed by subjecting the sintered laminated body to ultrasonic cleaning in butylacetate solvent, and bumps made of the sintered conductive paste were obtained.
EXAMPLE 3
In this example, the forming of the wiring pattern and the printing of the via-holes onto the green sheet were carried out by using CuO paste as a metal oxide paste. The substrate forming green sheet and the green sheet for bump forming layer were made similar to Example 1. The CuO paste for forming wiring was prepared by using an inorganic component made by adding 3 wt % of glass frit (LS-0803 glass powder with a mean particle size of 2.5 μm, made by Nippon Electric Glass Co., Ltd.) as an additive in order to increase the bonding strength to the CuO powder (mean particle size of 3 μm). Ethyl cellulose as the organic binder and a vehicle dissolved in terpineol were added to the inorganic component and mixed by means of a 3-step roll so as to obtain a proper viscosity, thereby to obtain the wiring forming CuO paste. The via-hole filling CuO Paste was prepared by further adding 15 wt % of the glass ceramic powder used in Example 1 to the wiring forming CuO paste. Holes were made in the green sheet for bump forming layer and the holes were filled with the via-hole filling CuO paste by the screen printing.
Specified numbers of the substrate forming green sheets and the bump forming green sheets were placed one on another so that the bump forming green sheet became the outermost layer, and were bonded by thermo-compression bonding to make a laminated body. Conditions of thermo-compression bonding were a temperature of 80° C. and a pressure of 200 kg/cm 2 . The substrate forming green sheet and the green sheet for bump forming layer were about 200 μm thick.
The sintering process will now be described below. First the binder was removed from the green sheet and the metal oxide paste by applying heat treatment to the sheets. This binder removal process was carried out at 600° C. The organic binders included in the green sheet and in the CuO paste used in this example are PVB and ethyl cellulose which decompose at temperatures of 500° C. or higher in air.
For the reduction of the CuO paste, the laminated body which was processed to remove the binders was subjected to a reduction treatment in an atmosphere of 100% hydrogen gas at 200° C. for 5 hours. X-ray analysis of the CuO paste in the laminated body thus obtained indicated that 100% of the CuO was reduced to Cu. After the reducing process, the laminated body was sintered in a mesh belt furnace in a pure nitrogen atmosphere at 900° C.
The laminated body made, as described above, was subjected to ultrasonic cleaning in order to remove the bump forming layer similar to Example 1. As a result, bumps made by sintering of the reduced metal oxide forming paste could be formed.
EXAMPLE 4
In this example, the substrate forming paste and the paste for bump forming layer were used to form a substrate layer end a bump forming layer on the surface of the sintered ceramic substrate.
MLS-1 made by Nippon Electric Glass Co., Ltd. was used as the inorganic component of the substrate forming paste. This inorganic material was mixed with polyvinyl butyral as an organic binder, di-n-butyl phthalate as e plasticizer and toluene and isopropyl alcohol as solvents being in such a proportion that gave an appropriate viscosity, thereby to obtain the substrate forming paste. The paste for bump forming layer was prepared by using alumina powder (ALM-41 with a mean particle size 1.9 μm, made by Sumitomo Chemical Co., Ltd) as the inorganic component. With ethyl cellulose being added as the organic binder together with a vehicle dissolved in terpineol being added to the alumina powder, and mixing them to obtain an appropriate viscosity (30 Pa·s) by means of a 3-step roll, the paste for bump forming layer was obtained.
The CuO paste for forming wirings was prepared by using an inorganic component made by adding 3 wt % of glass frit (LS-0803 glass powder with a mean particle size of 2.5 μm, made by Nippon Electric Glass Co., Ltd.) as an additive in order to increase the bonding strength to the CuO powder (mean particle size of 3 μm). Ethyl cellulose as the organic binder and a vehicle dissolved in terpineol were added to the inorganic component and mixed by means of a 3-step roll to obtain a proper viscosity, thereby to obtain the wiring forming CuO paste. The via-hole filling CuO paste was prepared by further adding 15 wt % of the glass ceramic powder used in Example 1 to the wiring forming CuO paste.
The substrate layer and the bump forming layer were formed on the surface of the sintered ceramic substrate by using the substrate forming paste and the paste for bump forming layer. First, the substrate forming paste was spread over the surface of the sintered ceramic substrate, with via-holes being formed therein and dried. Wiring pattern printing by using the wiring forming paste and via-hole filling by using the via-hole filling paste were carried out on the dried substrate forming paste layer by means of screen printing.
A bump forming layer having a plurality of holes was printed by using the paste for bump forming layer onto the substrate forming paste whereon the wiring pattern forming and via-hole filling had been completed. After drying the paste for bump forming layer, the holes in the bump forming layer were filled with the via-hole filling CuO paste by means of screen printing.
The sintering process will now be described below. First the binder was removed from the substrate forming paste, the paste for bump forming layer and the CuO paste by applying heat treatment. This binder removal process was carried out at 600° C. The organic binders included in the substrate forming paste, the paste for bump forming layer and in the CuO paste are PVB and ethyl cellulose which decompose at temperatures 500° C. or higher in air.
For the reduction of the CuO paste, the laminated body which had been processed in order to remove the binders was subjected to reduction treatment in an atmosphere of 100% hydrogen gas at 200° C. for 5 hours. X-ray analysis of the CuO paste in the laminated body thus obtained indicated that 100% of the CuO was reduced to Cu. After the reducing process, the laminated body was sintered in a mesh belt furnace in a pure nitrogen atmosphere at 900° C. A mixture gas of hydrogen gas and nitrogen gas can be used for the reduction treatment.
The paste for bump forming layer was removed from the laminated body made in the process described above, by ultrasonic cleaning similar to Example 1. Consequently, bumps composed of sintered bodies of the reduced metal oxide forming paste could be formed.
While the substrate layer with a wiring pattern was formed by using the substrate forming paste on the ceramic substrate and sintered in this example, the substrate layer may also be formed by printing the substrate forming paste onto the substrate forming green sheet and sintering the substrate layer at the same time as the substrate forming green sheet is sintered.
EXAMPLE 5
A substrate having conductive bumps was made in the manufacturing method of Example 1 by using a green sheet for bump forming layer 0.2 mm thick. FIG. 9 shows a view of the back face of a ceramic substrate of this example. The bump electrodes 16 were formed in a grid configuration with 1.27 mm pitch on the bottom surface of the ceramic substrate 15, with the conductive bumps whose heights were uniform at about 0.2 mm.
The ceramic substrate having the conductive bumps described above was mounted on a printed circuit board (FR-4) by soldering so that the bumps on the ceramic substrate were connected to the electrode pad on the printed circuit board. Solder paste was printed onto the electrode pad on a printed circuit board by means of screen printing. After arranging the ceramic substrate so that the bumps of the ceramic substrate were connected to the electrode pad on the printed circuit board, a reflowing of the solder was carried out in a nitrogen atmosphere at 230° C. in order to establish the connection. FIG. 8 shows a cross sectional view of the structure of the printed circuit board 14 whereon the ceramic substrate 15 having the bump electrodes 16 is mounted thereon. The ceramic substrate has electronic devices 13 being mounted thereon in advance. The ceramic substrate 15 is mounted on the printed circuit board 14 via the bump electrodes 16 by using the solder 12.
As described above, the ceramic substrate of the invention was mounted on the printed circuit board and the occurrence of a solder bridge in the solder section was evaluated. Solder bridges occurred between the electrodes which were arranged near to each other were zero among 1000 points. This means that connection having a very high reliability without solder bridge can be obtained by using the ceramic substrate of the invention.
Although Al 2 O 3 was used as the non-sintered material of the green sheet for bump forming layer and the paste for bump forming layer in the above embodiments, BeO, MgO, ZrO 2 , TiO 2 and BN could also be used.
The ceramic substrate of the invention has bump electrodes of the same height, and the bumps can be made high enough to prevent the occurrence of solder bridge. Increasing the height of the bump electrodes is also effective in suppressing the breakage of joints due to thermal stress generated between the printed circuit board and the ceramic substrate. Moreover, since the plurality of bumps have uniform heights, connection failure between the ceramic substrate and the printed circuit board can be reduced. Height of the bump electrodes can be controlled by regulating the thickness of the green sheet for bump forming layer, or the thickness of the paste for bump forming layer film. Moreover, since the bump electrodes can be formed at the same time as the ceramic substrate is made with this method of manufacturing the ceramic substrate of the invention, a ceramic substrate having bump electrodes can be made at a low cost. It is a matter of course that the ceramic substrate having bump electrodes of this invention can be used not only as a multi-chip substrate but also as a chip carrier.
Various other modifications will be apparent to and can be readily made by those skilled in the art without departing from the scope and spirit of this invention. Accordingly, it is not intended that the scope of the claims appended hereto be limited to the description as set forth herein, but rather that the claims be broadly construed. | The method of manufacturing a ceramic substrate having a plurality of bumps of the present invention, includes the steps of: forming a bump forming layer having a plurality of holes therein on at least one of upper and lower faces of a laminated body of green sheets; filling the holes in the bump forming layer with a bump forming paste; sintering the laminated body of the green sheets and the bump forming paste; and forming bumps made of the sintered bump forming paste by removing the bump forming layer. | 8 |
FIELD OF THE INVENTION
The instant invention relates to an apparatus for and a method of biologically treating organic substances.
BACKGROUND OF THE INVENTION
The ever increasing amount of rubbish produced by our society leads to ever more severe burdening of the environment. An important factor in overcoming the problems involved is the recycling of waste. One known means of recycling such substances into the natural circuit is the biological utilization of organic matter occurring as waste (such as plant and animal residues) or present as contaminants in matter (such as xenobiotics as harmful substances in earth).
Any such treatment should offer a quick, safe, low-power way of making renewed use of the matter treated, above all without any hazards to the environment. In present day biological waste treatment, however, these aims are reached only insufficiently. That is true particularly of the biological treatment of contaminated soil and the like, where neither the process conditions in existing plants are the best nor is the exclusion of ecological risks guaranteed. In the decontamination of soil, a basic distinction is made between handling methods of the material in its natural ground compound (in-situ) or after excavation of the earth (ex-situ). The ex-situ methods can be applied either on site or off site. The material is placed on a base which is sealed in downward direction to prevent any further contamination. And it is put in an enclosure (tent, building) for protection against the emission of gases exiting from such soils. The exhaust air in part is filtered before it gets back into the atmosphere.
SUMMARY OF THE INVENTION
It is the aim of the invention to provide an apparatus and a method by which all of the problems mentioned can be resolved. More specifically, it is an object of the invention to provide a containment system for the biological treatment of substances by means of microorganisms which system is suitable both for on-site and off-site use.
The invention provides an apparatus comprising at least two end segments adapted to be interconnected so as to present a sealed unit formed with at least one opening which can be closed upon charging of the system with the matter to be treated so that the biological process can take effect inside a closed, sealed system.
The instant invention offers a distinct reduction in energy because the gas volume to be transported and/or handled can be reduced drastically as compared to conventional systems, and there is no need for circulating the whole amount of air in a tent or building.
Advantageous further developments and modifications of the invention may be gathered from the remainder of the claims.
The invention provides a kind of installation constructed for joining according to the mechanical assembly technique in that intermediate segments which are open at both ends can be coupled to two end segments for optimum adaptation of the volume to the quantity of material to be treated.
The individual segments of the system are designed such that they can be transported by the usual carrier vehicles (e.g. on flat bed trailers).
In view of the fact that the system presents a sealed unit, all the gases which escape from the material or are released during the biological process can either be conducted actively in a circuit or subjected to purification by suitable filters before they are released into the surrounding atmosphere. In this context monitoring of the gas composition may be applied for process control.
According to a modification, the space above the contaminated material within the system is evacuated which not only promotes air circulation through the material, involving an improvement of the supply of oxygen to the microorganisms, but also serves as a safety measure of the integrity of the system in that any undesired gas escape into the surrounding air is prevented even if there should be a leak in the system because in such an event air will be sucked into the system.
In accordance with another embodiment of the invention the material is worked upon while being treated in the closed system, and the moisture content and other parameters which are important for the treatment are adjusted to optimum values. Such treatment parameters as such are known in the art.
In further development of the invention, the processing of the material to be treated as well as the monitoring and setting of optimum operating conditions are automated to the widest extent possible in the art. The instant invention is particularly well suited for fully developed automatic process operations which means that the material is treated in a way which excludes any contact between persons and the material being treated or the resulting gases.
Optimum adjustment of the degree of humidity and other process parameters which are decisive for the treatment and monitored constantly in a closed system, either can be effected at the same time that the material is being processed in the apparatus or independently thereof.
BRIEF DESCRIPTION OF THE DRAWING
The invention will be described further by way of example with reference to the accompanying diagrammatic drawings, in which:
FIG. 1 is a side elevation of an apparatus consisting of two end segments and one intermediate segment;
FIG. 2 is an axial longitudinal section of the apparatus shown in FIG. 1;
FIG. 3 is a front end elevation of the apparatus shown in FIG. 1;
FIG. 4 is a cross section of the apparatus shown in FIG. 1, and
FIG. 5 is an axial longitudinal section of a second embodiment of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
As shown by way of example in FIGS. 1 to 4, the apparatus 1 is made up of two end segments a, c and one or more intermediate segments b which are open towards both ends, the segments being interconnected by sealed flanges 3a, 3b, 4b, 4c. Flanges 2a and 5c are provided for closing the container. Each segment includes at least one opening which can be tightly closed. The individual segments are designed such that they can be carried by conventional transportation vehicles. To that end, the segments are provided with means which permit easy loading and unloading of carrier vehicles. In the embodiment shown, the base dimensions of the segments are greater than their height so that the segments can be shipped lying on the side. Each end segment may be provided with one or more door elements. The end segments are adapted to house the aggregates/machines required for automatic process operations.
One or more vacuum pumps 10 are connected to the individual segments at position 11 above the material 8 to be treated so as to generate vacuum in the system. A respective connecting line 12 at the bottom of each segment can be hooked up to the vacuum pump(s). Furthermore, a means 6 is provided for working the material, as well as a sprinkler means 7.
The second embodiment of the invention illustrated in FIG. 5 shows an alternative method of treating material in the closed system. Here, a knife-like device 20, 21 mounted on a rotating axis 22 is moved within the system on rollers 25 along rails 24 from one end segment to the other while it works on the material. The power required for this movement is supplied electrically or hydraulically to the system. Also this embodiment may be equipped with a sprinkler means 28 to act on the material while it is being treated.
Once the system has been loaded, it is closed and vacuum is applied to the surface of the material to be treated by means of the vacuum pump(s) 10. Oxygen may be supplied through connections 30 and the connecting lines 12. Reference numeral 32 is a connecting line between vacuum pump 10 and connection 30. The supply of oxygen may be effected under pressure. The vacuum pump(s) 10 and connection(s) 30 are connected by means of at least one conduit (32) which establishes a circuit including a closed system. The material may be treated inside the machine from one end to the other at certain intervals, depending on the progress of treatment and on process operating conditions. Measures of maintaining optimum process conditions either can be taken simultaneously with the ongoing treatment or independently of the same. Reference numerals 9a and 9b of FIG. 3 are bottom plates of the container.
This way of realizing process operations permits the installation to be operated fully automatically. By virtue of the vacuum created, gases cannot exit from the system into the atmosphere even if leaks should occur. Resulting gases from the treatment either are circulated within the system or cleaned by filters before being released from the system.
Gases are supplied separately to each segment and can be metered and controlled individually. The gas supplied either may be oxygen or another gas (perhaps a gas mixture) which will promote the continuation of the biological process. The gas may be preheated prior to its introduction into the system. Furthermore, heating the material to be treated provided for during the biological process will accelerate the process. Any available sources of waste heat, either external or, for example, the various instruments of the system, may be utilized to heat of the material.
For sampling during treatment, the apparatus is provided with apertures 5 which can be closed. They may include membranes which help in the drawing of samples. Since vacuum prevails in the system, no toxic gases can leave the system when samples are taken.
During normal operation, seeping water should not appear. If, however, excess liquid does show up, it may be sucked out of the system through the connecting lines 12 and be dealt with accordingly. In general, the material 8 to be treated is subjected to pretreatment, as may be required, prior to loading. What is aimed at in this context, for instance, is size fractioning (perhaps breaking up the material), improvement of the structure by homogenization, and, if desired, the addition of structural agents. Moreover, various parameters, such as moisture, pH, and nutrients are adjusted by means of adjuvants, and suitable microorganisms are added, if required. Also, the biological activity of natural populations of microorganisms could be exploited in the biological treatment of certain substances by mixing substances with an organic matrix (such as earth or compost) and treating the mixture in the apparatus. It is only by the closed, variable volume system of the invention that such a strategy becomes feasible.
In modifying the method desribed above, the apparatus illustrated in FIGS. 1 through 5 also may be used to introduce harmful substances into matter, especially to introduce harmful substances into soil and the like. The underlying aspect of the invention in this instance is the problem of having to "remove" certain harmful substances, especially chemicals in a non-harmful way. The pharmaceutical industry, for example, is faced with the problem of having to withdraw from circulation certain chemicals in a manner which does no harm. Microorganisms are contained "naturally" in soil, and they can be put to use without any additional measures to metabolize certain chemicals. In this case, the chemicals are made to enter the soil and metabolize by means of an apparatus as specified above with reference to FIGS. 1 to 5. Where the given microorganisms already present in the soil are not "specialized" to the chemicals to be metabolized, populations of microorganisms which are suitable to cause the decay of any particular chemicals by metabolization may be added to the soil. | An apparatus and method is described for treatment of organically contaminated soil in which a modular structure having a plurality of interconnected segments with two end segments and at least one intermediate segment, allows for the formation of a system closed off from the outside atmosphere such that a vacuum can be maintained in the system and one or more gases can be supplied to the system, and in which at least one conduit interconnecting the gas supply with the vacuum such that a circuit is established for circulating the gas in the closed system. | 1 |
BACKGROUND OF THE INVENTION
The present invention relates to electrical test apparatus and, more particularly, to apparatus for identifying and testing individual electrical conductors in a bundle of unidentified conductors.
Apparatus for identifying electrical .[.connectors.]. .Iadd.conductors .Iaddend.within a group of electrical .[.connectors.]. .Iadd.conductors .Iaddend.either intentionally or unintentionally (shorted) electrically interconnected at a remote location is not new. For example the simple "bell and battery" of FIG. 7 is well known and well used in the electrical arts. Given a pair of cables 150 and 152 comprising a plurality of insulated electrical conductors 154 and 156, respectively, any electrical interconnection between a conductor 154 and a conductor 156 can be determined by sequentially applying the test leads 158 of the test set, generally indicated as 160, to the possible combinations of conductors 154 and 156. As can be seen in the circuit diagram of FIG. 8, the test set 160 comprises a battery 162 connected in series with a bell 164 between the two test leads 158. When connected to an electrically interconnected pair of conductors 154, 156 as shown in FIG. 8, the circuit is completed between the test leads 158 and the bell rings.
Telephone systems present unique problems in the testing and identification of electrical cables. Telephone networks employ multi-conductor cables to interconnect remotely located telephone switching systems (such as that located at the central office) to other switching systems or subscriber equipment. The multiconductor cables comprise a plurality of twisted wire pairs. A "pair" comprises the two wires that are used to connect the central office and subscriber equipment. One wire of a pair is referred to as the "tip" and the other as the "ring". Each pair of wires is bundled in groups of 25 or 100 pairs. Cables, in turn, may include as many as 3600 pairs. Cable is placed, whether aerial or underground, in sections. A typical 1200 pair cable reel length of 22 AWG gauge wire, with polyethylene conductor insulation, is 1250 feet in length. Splices are required throughout the cable network to connect such sections to one another and also to connect main cables with feeder and distribution cables of smaller cable pair count.
Until recently, the splicing (wire-joining) method commonly employed in the telephone industry involved splicing each individual pair by joining the tip wires, one to another, with discrete connectors, and the ring wires, one to another, each with a second discrete connector. Such a process is both time-consuming and expensive.
Recently, a method and associated hardware has been adopted in the telephone industry to perform the splicing operation through the joining of groups of pairs (in many cables, wire pairs are bundled in 25-pair groups). This is commonly referred to as "modular splicing".
Modular splicing equipment includes what is commonly referred at as a "cutter-presser" device in which a plastic module, comprising several parts, is employed. Examples of such splice modules are ones manufactured by the 3M Company, St. Paul, Minn. and sold under the name MS 2 module and one called the 710 Connector used in the Bell System (described in Bell System practice section 632-205-222, Issue 1, October, 1973). Individual wires are placed in identified slots in the module. When all of the wires are properly positioned in the module, the parts of the module are clamped to simultaneously provide electrical connection between appropriate wires and cut off the excess wire ends.
The presser device used in connection with the 710 Connector also includes means for providing electrical access to the wires in the module through test ports in the module body. An electrical connector on the cutter-presser equipment provides access to the 25 pairs spliced into the module. Various types of test sets could, therefore, be connected to the cutter-presser device for testing using the test ports and the electrical connector provided. Functionally similar access to the MS 2 module is also provided for connecting test equipment. While provision has thus been made for test equipment, to date, no test equipment is available for interfacing through the provisions thus provided to allow rapid and accurate testing of the type of cable splice which normally occurs in cable rearrangements using such apparatus.
There are may reasons for rearranging cables. For example, a section of cable may become faulty and need to be replaced. A cable route may have to be relocated due to a change in surface or underground conditions. Increased facilities over a particular cable route may be required from a certain point in the field to a more distant subscriber terminal equipment point. In many if not most, cable transfers, telephone operating companies attempt to make such transfer without interrupting service to the customer and often even perform the transfer while a voice conversation is being carried on the pair being physically respliced. To accomplish this without disruption or inconvenience to the customer imposes stringent limitations on what test apparatus can do in accomplishing its functions.
One type of transfer in which the cable test set of the present invention may be employed is shown as part of FIG. 1. In FIG. 1, there is shown an old cable (cable A) in which a section is to be replaced by a section of new cable (cable B). The new cable is spliced to the old cable at a first splice location using a bridge-tap or half-tap method, i.e. each wire in the old cable is tapped and a wire from a new cable is electrically connected in a "T" configuration. This bridge-tap or half-tap at the first splice location will not normally disturb a working line, even if in use, in normal voice communications. However, the critical phase of the transfer, which is normally referred to as "cut-closed" transfer, is where the free end of the new cable is now joined to the old cable at the second splice location. Unless the pairs are properly identified, and within each pair the proper polarity (ring-to-ring and tip-to-tip) are spliced, service will be interrupted. It is at this second splice location and for this identification and verification that the test apparatus of the present invention is to be used.
Additionally, the requirement for the inclusion of a battery, such as that employed in the "bell and battery" test set of FIGS. 7 and 8 is one which causes concern to users of such apparatus. Batteries are, typically, heavy and prone to give out at the moment of least convenience. Inasmuch as much of the previously discussed splicing and attendant testing is accomplished in locations which cannot easily be referred to as "convenient" (such as on raised poles and underground cable vaults), the elimination of a battery or other internal power supply for operation is a high priority design criteria.
Wherefore, it is the object of the present invention to provide a test set for accomplishing telephone cable splice testing and verification with apparatus requiring no internal power supply.
SUMMARY OF THE INVENTION
The test set of the present invention comprises a first terminal for connecting an electrical tone generating source to the test set; a second terminal for connecting the test set to the reference potential of the tone generating source (typically ground potential); switch means having a first input and an output for selectively connecting between the first input and the output, the first input being connected to the first terminal; a pair of matched coils connected on one end to the output of the switch means; first means connected to the other end of one of the coils for electrically contacting a first selected wire within an electrical cable; second means connected to the other end of the other of said coils for electrically contacting a second selected wire within an electrical cable; third means for electrically contacting a third selected wire within an electrical cable; fourth means for electrically contacting a fourth selected wire within an electrical cable; and, a pair of matched meter means connected respectively between the third electrical contacting means and the second terminal and between the fourth electrical contacting means and the second terminal for indicating the voltage thereacross. The aforementioned pair of meters comprise linear indicators mounted in side-by-side relationship reversed i.e. the maximum point of each meter is adjacent the minimum point of the opposite meter and the minimum point is opposite the maximum point, whereby the meter movements work in opposition to form a combined meter indicating pair display whereby the status of tip and ring pairs can be ascertained from the actions of the combined meter pair indicating display. In the preferred embodiment, the matched coils are bifilar windings on a single core and perform two functions. When sending tone, the matched coils present a high impedance to the customer's talking circuit so the conversation is not disturbed; simultaneously, the coils present a low impedance path to the identifying tone to assure a high level of signal being applied to the line. The second function performed by the matched coils is during use of the test set for verifying. In this mode of operation, the coils are used to provide a loop across the customer's line to lower the line voltage or seize the line in the case of an idle line. The low resistance of the coils is necessary to cause an adequate drop in the line voltage while providing a high impedance to the customer's talking circuit.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a simplified drawing of the test set of the present invention connected to test a section of cable being spliced.
FIGS. 2(a)-(h) is a series of pictorial representations of various indications to be found when using the dual meter indicating display of the present invention and the tip/ring wire pair status associated with each such indication.
FIG. 3 is a schematic drawing of a tested embodiment of the test set of the present invention.
FIG. 4 is a simplified schematic drawing of the operation of the combined meter pair indicating display used in the present invention.
FIG. 5 is a detailed view of the meter pair indicating display of the present invention.
FIG. 6 is a schematic drawing of the novel automatic ground start circuit employed within the present invention (eliminated from the schematic drawing of FIG. 3 for clarity).
FIG. 7 is a simplified drawing of a prior art bell and battery test set being employed to test two cables for shorted conductors therein.
FIG. 8 is a simplified circuit diagram of the apparatus of FIG. 7.
FIG. 9 is an optional configuration for the combined meter pair employed in the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring first to FIG. 1, the test set of the present invention, generally indicated as 10, is seen to be portable and housed in a suitable transit case 12 having a cover (not shown) which, when raised, exposes a faceplate 14 as shown. The faceplate 14 includes a rotary 25-pair selector switch 16 for accessing individual tip/ring wire pairs according to their position in a cutter-presser device. The individual pairs are connected to the test set 10 at a 50-pin connector 18, such as a Cinch-Jones connector commonly used for test sets in the telephone industry. The connector 18 is engaged by a 25-pair test cord 20 at one end; the cord 20 terminating at the other end in a connector 22 adapted for connecting to the cutter-presser device 24 which in turn provides electrical access to each wire of the 25-pair.
A pair of edgewise meters 26 and 28 (i.e. having indicating pointers moving along a straight line) are mounted in the faceplate. They are, respectively, a tip meter 26 and a ring meter 28. Further details of the meters 26, 28 will be discussed hereinafter.
Input binding posts T 30 and R 32 provide access points for connecting external input equipment, such as a tone source 33, to the tip (T) and ring (R) of the pair accessed by the selector switch 16. A third binding post, G 34, is used to ground the test set 10. "Ground" is the usual reference potential employed with all the equipment including the tone source 33. A second set of binding posts T 36, R 38, and G 40 provide output access points for connecting a tone receiving set such as an amplifier (not shown) or headset 46. A single pair cord 48, such as a B-transfer cord having a clip 50, is employed to provide manual electrical access to any particular wire pair.
In addition to the 25-pair selector switch 16 previously mentioned, faceplate 14 includes seven push-button switches, 52, 54, 56, 58, 60, 62 and 64 designated K1, K2, K3, K4, K5, K6, and K7 respectively. For ease of operator use, the seven push-buttons associated with switches 52-64 are also labeled on faceplate 14 as follows:
K1=DIRECT INPUT ACCESS
K2=TONE SIMPLEX
K3=BALANCE TEST
K4=SEND TONE
K5=VERIFY HALF TAP
K6=SINGLE PAIR CORD
K7=25-PAIR SWITCH
K1, K2, and K3 (52, 54, 56) are interlocking (as indicated by the dotted interconnections). That is, only one push-button can be operated at a time. Depressing one push-button releases either of the other two.
K4 and K5 (58, 60) are interlocking with K5 (60) having momentary action. That is, K5 (60) cannot be locked.
K6 and K7 (62, 64) are interlocking. When referring to the schematic drawings of FIGS. 3 and 6 to be discussed hereinafter, it will be noticed that push-button (switch) K6 (62) does not appear. When it is depressed it unlocks K7 (64). When K7 (64) is depressed, it locks, therefore, all contacts can be on one switch i.e. K7 (64).
It is to be understood that the use of the seven interlocking push-button switches 52-64 is a preferred matter of choice only. The interlocking action described provides a preferred action discouraging inadvertent operator errors. Other switch types could, of course, be employed without the interlocking action.
Note further that the push-button switches 52-64 employed provide up to four individual SPDT combinations on each switch, (designated A, B, C, and D). These appear on the schematic drawings to be described hereinafter as a suffix to the push-button identity, (i.e. K7B is a spring contact combination on push-button K7). All push-button switches 52-64 are shown in the schematics of FIGS. 3 and 6 in their off or unoperated positions.
The faceplate 14 also includes a pair of neon lamps 66, 68 to indicate when voltages in excess of 90 volts are present on the pair to which the test set 10 is connected.
As previously mentioned briefly, a diagrammatic representation of a cable transfer involving a section replacement is shown in FIG. 1. Cable A is shown as the "old" cable which can be assumed to be connected at the left end to the central office (not shown), passing through first and second splice locations (for example, manholes) and proceeding to the right to numerous subscribers (also not shown). Within cable A, there is shown two representative pairs 1 and 2, designated "pair 1A" comprising tip T1A and ring R1A, and "pair 2A" comprising T2A and R2A (tip and ring respectively). Cable A may contain hundreds of such pairs. In the process of replacing the old cable A section between the first and second splice locations, the "new" cable B if first bridge-tapped or half-tapped to cable A at the first splice location as shown. Cable B is also shown containing two respective pairs identified as "pair 1B" and "pair 2B". Pair 1B comprises tip and ring T1B and R1B respectively, and pair 2B comprises T2B and R2B.
At the second splice location, in order to complete the section replacement, cable B must be spliced into cable A. To do this, with the modular joining method, the cutter-presser modular splicing device 24 has been set up and it is assumed that 25 pairs, including pair 1A and pair 2A, have been placed into the cutter-presser head 24. Consequently, this 25-pair group is shown to be electrically connected to the test set 10 through the 25-pair cord 20 that connects the cutter-presser 24 to the connector 18 on the faceplate 14 of test set 10.
The two meters 26, 28 can now be connected to any one of the pairs in the 25-pair group of cable A by rotating switch 16 to the position number of the pair in the cutter-presser device 24. This allows the quick determination of the status of any pair, i.e. "working" (either "idle" (on-hook) or "in-use" (off hook)), or "dead" (vacant) as determined by the position of the meter pointers relative to suitably designated portions of the meter scale according to techniques to be described hereinafter. It also permits the determination of the polarity of each side of the selected pair so as to prevent a reversal.
By connecting an external tone source 33 between grounded G binding post 34 and ring (R) binding post 32 as shown in FIG. 1, the tone may be sent either via one of the pairs connected through switch 16 to the presser head 24 or via the single pair cord 48. Some telephone cables have each 25-pair groups segregated by a colored binder, as this simplifies locating an individual pair. If both the old and new cables have 25-pair identical binder groups and have been half-tapped without splitting groups, then the fastest method of identifying pairs is by sending tone on one pair of the new cable B via the single pair cord 48. This is accomplished by connecting the single pair cord 48 across one of the pairs in the selected binder group with the B-transfer clip 50, for example pair 2B as shown, and depressing single pair cord switch K6 62. This connects tip meter 26 between ground and side T2B of pair 2B and ring meter 28 between ground and side R2B. Meters 26 and 28 then indicate the status of pair 1B.
One of the principal features of the test set 10 of the present invention is the use of the two meters 26 and 28, each of which is attached to one side of the pair being half-tapped, to indicate, in combination, the pair condition. The simplified circuit of FIG. 4 represents the test set 10, the Central Office battery (supply voltage), and the Tip and Ring conductor's equivalent resistance between the supply voltage and the point at which the pair is tapped (denominated as "Tip Equivalent Resistance" and "Ring Equivalent Resistance", respectively). For each telephone pair to which the test set is attached, there is additional resistance beyond the point at which the tap is made, which comprises the remaining resistance of the Tip and Ring and also the resistance of the subscriber's instrument (denominated as "Unknown Resistance"). The circuit further shows Tip meter 26 and Ring meter 28 tapped intermediate the Tip and Ring Equivalent Resistances and the Unknown Resistance. The meters thus indicate a voltage which is a function of the value of the Unknown Resistance. The total of the two readings (one on each meter) is equal to the supply voltage if, and only if, the Tip and Ring Equivalent Resistances are equal to each other, i.e. balanced. In a typical telephone circuit, the supply voltage provided by the Central Office battery is above 46 Volts and generally is equal to 50 Volts. The meters 26 and 28 preferably are edgewise meters placed closely adjacent to one another, as shown in FIG. 5, with the pointers moving in parallel straight-line paths. The meter scales are preferably identical with the zero graduation mark on one meter scale being directly opposite (aligned) the graduation mark equivalent to the supply voltage of the line that is normally employed in telephone circuits, for example 50 Volts. In the preferred configuration, the 50-Volt graduation line corresponds to the maximum reading on the meter scale and 0 corresponds to the minimum reading on the meter scale. However, it may be desirable in some cases to provide a meter scale which extends beyond the voltage graduation corresponding to the normal supply voltage of the line with the meter faces off-set as shown in FIG. 9 so that either meter may read beyond 50 Volts (for example, to indicate special circuits which may have a voltage of 150 Volts) so long as the supply voltage of the typical telephone circuit on one meter scale corresponds to the zero reading on the other meter scale, and vice versa. In the simplified circuit shown in FIG. 4, with the preferred meter arrangement of FIG. 5, it will be apparent that regardless of where the test set is tapped in the telephone pair, and therefore regardless of the "Unknown Resistance", the meter pointers will remain in line if the Tip and Ring Equivalent Resistances are equal. Such alignment further indicates the status of the line, i.e. "dead" (vacant) or "working" (idle or busy). Through the provision of suitable graduations on the meter scale, as will be explained hereinafter, the status of a working line as either "in use" (busy) or "idle" can also be determined. Finally, if the line is working, the pointers align themselves in a manner which indicates that the Tip and Ring at the point at which the tap is made are straight or reversed. A "reversal" occurs when a splice intermediate the Central Office and the point at which the tap is made is in error such that the Tip and Ring of the "Central Office" pair are attached to the Ring and Tip, respectively, of the "field side pair".
In the preferred configuration of meters 26, 28 of FIG. 5, the short line 70 on the face of the meters 26, 28 indicates the zero position for the moving pointer 72. The two full lines 74, 76 on either side of the meters 26, 28 (corresponding to 5 volts and 45 volts respectively) bound the area that the pointers 72 will move into when a line "in use" (busy line) is encountered. The full line 78 in the center of the meter indicates exact mid-scale (25 volts).
Referring now to FIG. 2, various indications are shown for the meters 26, 28 of FIG. 5 operating in combination as an indicating display. The meter indications in FIG. 2 apply only to readings encountered when the SEND TONE button (K4 58) is not operated (when the SEND TONE button is operated, the meters 26, 28 respond to tone returning through the half-tap connections). Briefly, the conditions shown in FIG. 2 are as follows:
FIG. 2(a)--A vacant pair or open connection is indicated by the absence of response of either meter.
FIG. 2(b)--An idle line is indicated when the ring meter pointer moves full scale to align with the tip meter pointer.
FIG. 2(c)--A reversed line is indicated when the tip meter pointer moves full scale to align with the ring meter pointer.
FIG. 2(d)--A line "in use" (busy line) is indicated when both meter pointers align with each other on the right side of the meters.
FIG. 2(e)--A reversed line "in use" (busy line) is indicated when both meter pointers align with each other on the left side of the meters.
FIG. 2(f)--An open tip is indicated when the ring meter pointer is in the "in use" (busy) area while the tip meter pointer has not moved.
FIG. 2(g)--An open ring is indicated when the tip meter pointer is in the "in use" (busy) area while the ring meter pointer has not moved.
FIG. 2(h)--A split pair or special circuit is indicated when both meter pointers move but fail to align with each other.
With the foregoing in mind and referring once again to FIG. 1, operation of the test set 10 of the present invention will be described briefly whereby the detailed schematic diagrams to be discussed hereinafter will become more readily apparent. Tagging and Verifying:
This procedure is recommended when the binder group counts on the old and new cables are identical, i.e. at the half-tap location all pairs in one group were joined to a second group of identical count. When group-for-group wire joining has been performed at the first location, the specific group which corresponds to the group being tested in the module can be located. It is, therefore, passible to send tones through the cord 48 connected to one of the pairs in the proper group in the non-terminated cable using the B-transfer clip 50 to permit identification of the corresponding pair in the group terminated in the module through the cutter-presser 24 via the connector 22 and cord 20. This method completely verifies the half-tap or bridge-tap made at the first location (whether at the central office or at a first splice location) for complete continuity as well as determining correct polarity. The steps of the procedure are as follows:
1. Make the connections shown in FIG. 1.
2. Depress the SINGLE PAIR CORD (K6 62) button. Depress the TONE SIMPLEX (K2 54) button. Momentarily depress the VERIFY HALF-TAP (K5 60) button to assure that the SEND TONE (K4 58) button is released.
3. Connect the B-transfer clip 50 to the cable pair in the cable group which was wire joined at the first half-tap location to the cable group terminated in the module of the cutter-presser device 24. The meters 26, 28 will indicate the status of connection and line condition according to the previously discussed states of FIG. 2.
4. If the conditions of FIGS. 2(a) through 2(e) are encountered, depress the SEND TONE (K4 58) button. This operation applies a simplex (inaudible) tone through the single pair cord 48 and B-transfer clip 50 into the pair.
5. Rotate the 25-pair switch 16, pausing briefly on each position until tone is received.
6. For vacant pairs (the condition of FIG. 2(a)), observe that both meters 26, 28 are responding to the tone. To verify polarity, depress the DIRECT INPUT ACCESS (K1 52) button. This applies tone on the ring side of the line only (as terminal R 32 is connected directly to terminal R 38) and only the ring meter 28 pointer 72 should respond. Prior to proceeding on to the next pair, depress the TONE SIMPLEX (K2 54) button to restore sending tone to both tip and ring. (This operation only applies when the vacant pairs have been half-tapped.)
For working pairs (the conditions of FIGS. 2(b) through 2(e), depress (and hold depressed) the VERIFY HALF-TAP (K5 60) button. The meter pointers 72 will be aligned with each other if the pair is not split. The VERIFY HALF-TAP (K5 60) button should then be released. The meter pointers 72 will move to a different position and remain aligned if a half-tap exists. Now depress the 25-PAIR SWITCH (K7 64) button. The meter pointers 72 should continue to indicate on the same side of the meters if the polarity is proper. If the meter pointers 72 move to the opposite side of the meters 26, 28, then the pair is reversed. To correct this, reverse the tip and ring when placing the non-terminated pair in the module of the cutter-presser device 24. Identifying special circuits:
Adjacent the tip and ring meters 26, 28 are two neon lamps 66, 68 for indicating the status of a pair in a special (higher voltage) circuit, e.g. generator pair (ringing signal source used with some PBX boards), burglar and fire alarms. One or both of the lights 66, 68 will be illuminated when such special working pairs have been encountered.
Known, inactive ground start circuits can be verified by temporarily shorting the ring (R) input binding post 32 to the ground (G) input binding post 34 while holding the VERIFY HALF-TAP (K5 60) button depressed. After the short is removed and with the VERIFY HALF-TAP (K5 60) button still depressed, the meter pointers 72 will align with each other if a proper half-tap exists. This will be discussed in greater detail hereinafter in relation to automatic ground start circuitry incorporated in one embodiment of the present invention. Verification:
This procedure is used when the new cable has been previously tagged. The steps are as follows:
1. Make connections as shown in FIG. 1. Depress the VERIFY HALF-TAP (K5 60) button to assure that the SEND TONE (K4 58) button is released.
2. Depress the 25-PAIR SWITCH (K7 64) button. Rotate the selector switch 16 to position 1. Attach the B-transfer clip 50 to pair 1 of the non-terminated cable.
3. Depress the TONE SIMPLEX (K2 54) button. If pair 1 is a good working pair (idle or in-use), the meter pointers 72 will align with each other as in FIGS. 2(b) through 2(e).
4. Depress the SINGLE PAIR CORD (K6 62) button. The meter pointers 72 will align (indicating conditions corresponding to FIG. 2(b) through 2(e)).
5. Depress the VERIFY HALF-TAP (K5 60) button. The meter pointers 72 will align (corresponding to conditions of FIGS. 2(b) through 2(e)). If the meter pointers 72 move but do not align, the pair is split (condition of FIG. 2(h)). If the meter pointers 72 do not move, no half-tap exists between the two pairs (FIG. 2(a)). If all meter readings in steps 3, 4 and 5 above are on the same half of the meter, i.e. on the right half (straight) or left half (reversed), the half-tap is proper and the pair is straight. If one of the three meter readings (steps 3, 4, and 5) are not on the same half of the meter as the other two readings, the pair is reversed. To correct, reverse the tip and ring before placing the non-terminated pair in the module of the cutter-presser device 24.
6. If pair 1 is a vacant pair, neither meter pointer 72 will respond (condition of FIG. 2(a)). Depress the SEND TONE (K4 58) button. Both meter pointers 72 should respond to tone. Depress the DIRECT INPUT ACCESS (K1 52) button to apply tone to only the ring. If only the ring meter 28 pointer 72 moves, polarity is proper. (Note, step 6 applies only if the vacant pair has been half-tapped).
Tagging:
This procedure is recommended if the pairs at the first half-tap location were not spliced binder-group-for-binder-group, i.e. a pair in one group at the first location was joined to a pair in a second group. In this method, tone is sent from the tone source, through the module of the cutter-presser device 24 via cord 20 and connector 22, and through the first half-tap location so that it may be searched for at the non-terminated cable end. All pairs in the cable may be tagged first and the verification method discussed above then used to prove out the half-tap and polarity. Alternatively, after each pair is tagged, the above discussed verification method may be used to prove out the half-tap and determine the polarity, i.e. verification of tagged pair at a time. Tagging is accomplished by the following steps:
1. Make the basic connections as shown in FIG. 1. (The headset 46 and the single pair cord 48 can be omitted).
2. Depress the 25-PAIR SWITCH (K7 64) button and the TONE SIMPLEX (K2 54) button, and momentarily depress the VERIFY HALF-TAP (K5 60) button to release the SEND TONE (K4 58) button.
3. Rotate the switch 16 to position 1 for pair 1.
4. If the meters 26, 28 indicate conditions corresponding to FIG. 2(a) through FIG. 2(e), depress the SEND TONE (K4 58) button. This operation applies simplexed (inaudible) tone to the pair selected through the rotary 25-pair switch 16.
5. Using the amplifier 42 and probe 44, locate the half-tapped pair by searching through the unterminated cable ends.
6. Repeat steps 3 through 5 above for positions 2 through 25 of the 25-pair switch 16.
Balance Testing:
This procedure provides a convenient way for balance testing the new cable count prior to having the heat coils placed by central office personnel. The procedure is as follows:
1. Make the basic connections as shown in FIG. 1 omitting the single pair cord 48. Note, use the headset 46 only, do not use an amplifier. Connect the headset 46 to the Ring (R) terminal 38 and the Tip (T) terminal 36.
2. Depress the BALANCE TEST (K3 56), SEND TONE (K4 58), and 25-PAIR SWITCH (K7 64) buttons. This operation applies simplex (inaudible) tone through the selector switch 16 to the pair under test.
3. Rotate the switch 16, pausing on each position to listen for the presence or absence of tone. Good balance pairs will produce a barely audible signal.
4. To verify for the absence of shorts, change the one connection of the headset 46 from the ring (R) terminal 38 to the Ground (G) terminal 40 and depress the DIRECT INPUT ACCESS (K1 52) button. This operation places tone on the ring side of the line only as previously discussed.
5. Rotate the selector switch 16. Any lines that are shorted will produce a tone in the headset 46.
Note that if the line is in use during any of the procedures described above, the subscriber is not disturbed by the application of the tone since it is nearly inaudible because of being applied simplex. Moreover, because the loop placed on the pair is a high-impedance, low-resistance short, it is also nearly inaudible to the subscriber. This will be discussed in greater detail in reference to the schematic diagrams of FIGS. 3 and 6 to be described hereinafter. If the line is idle when the loop is placed on the pair, the line relay at the central office is operated and the line assumes a balanced condition (if a proper identification of the "new" cable pair has been made) and is so indicated by the meters 26 and 28. If, rather than a normal home subscriber line, the line under test is connected to a pay station, or any ground start circuit, the test set 10 is adapted to recognize this type of line and automatically place a ground onto the pair so as to operate the line relay according to techniques to be described hereinafter.
An additional feature of the test set 10 of the present invention is that the meters 26 and 28 are also capable of being used to locate and/or verify the tone in lieu of using the headset 46 or an amplifier alone. This is possible because the meters 26, 28 are disconnected from the new cable pair and reconnected in series with capacitors to binding posts 34 and 36 (T and R) when the SEND TONE (K4 58) button is depressed i combination with the SINGLE PAIR CORD (K6 62) button. The meters 26 and 28 also have capacitors and diodes added in series (see FIG. 3 discussed hereinafter) so that they can respond to the tone and not to direct voltage as previously.
Referring now to FIG. 3, the schematic of a tested embodiment of the present invention is disclosed. Remembering the simplified drawing of FIG. 4, it should be readily apparent that the schematic of FIG. 3 represents two symmetrical circuits. This is proper inasmuch as each half of the circuit measuring one half of the "pair" under test with its associated meter 26, 28 must be matched (balanced) if it is to indicate imbalances in the lines of the pair under test. Thus, it will be noted that the input terminals 30 and 32 selectively connect to a common input point 80. One side of the C contacts of switch K5 60 is connected to the common point 80. The movable switch arm of the C contacts of switch K5 60 is connected to one side of a pair of matched coils. In the preferred embodiment, the coils comprise bifilar windings 82 and 84 of a transformer T1 generally indicated as 86. The other side of windings 82 and 84 are connected respectively through the A contacts and B contacts of switches K5 60 and K7 64 to the two wiper arms 88, 90 of rotary switch 16. The fifty output lines 92 from switch 16 are connected to the 50-pin connector 18 whereby fifty individual connections to the cutter-presser 24 can be affected through 25-pair test cord 20 attached thereto.
The other half of the circuit comprises a connection between the two connectors 94, 96 of the B-transfer clip 50 through the two meters 26, 28 respectively to the ground (G) terminal 34. This connection is selectively connectable as shown through switches K7 52, and K4 58, whereby the various tests hereinbefore described can be accomplished.
For example, in sending a tone as previously described, the tone source 33 is connected to input terminal R 32. The tone thus proceeds from terminal R 32 through the A contact of switch K1 52, through common point 80 and contact C of switch K5 60, to transformer T1 86 where it splits to pass through the two windings 82, 84; thence through the A and B contacts of switch K5 60 to the A and B contacts of switch K4 58. In the SEND TONE configuration, contacts A and B of switch K4 58 are closed allowing the tone to pass therethrough, through the capacitors 98, and from there through the C and D contacts of switch K1 52 and the C and D contacts of switch K7 64 to the connectors 94 and 96 of B-transfer clip 50, through which they are injected into the tip and ring of a selected pair. The tone, thus applied, passes through the selected pair, through the half-tap into the cable, back down the cable, where it is picked up through the 50-pin connector 18, passes into the appropriate output lines 92 of switch 16 and is picked up by the wiper arms 88, 90 thereof. The tone, thus received, passes through contacts A and B of switch K7 64 and thence through capacitors 100 and diodes 102 to meters 26 and 28 respectively; from whence it passes to the ground terminal 34 and thence to ground to complete the circuit.
The capacitors 100 in combination with diodes 102 provide the novel capability of the present invention, previously mentioned, wherein the meters 26, 28 can be used to detect a tone contrary to the usual procedure of the prior art wherein tones are only audibly detected. The capacitors 100 are inserted in series in the meter path to make the meters 26, 28 respond only to the varying audible tone and not direct current which may be on the line. The series diodes 102 are provided to discharge the capacitors 100. A capacitor 104 is placed in parallel across each meter 26, 28 to eliminate ripple. Note that the path to ground passes through the C and D contacts of switch K4 58 which also simultaneously disconnects the direct internal connection to the tone which would otherwise exist. Note also in this connection that the bifilar windings 82 and 84 act as high-impedance low-resistance elements within the path. The windings 82, 84 by providing a high impedance path minimize any change of voice level if the line is in use.
During the verifying procedure described above, the circuit, because of the switching, operates as two separate balanced circuits. Note that while the description hereinafter shows switch K7 64 in its single pair position (undepressed) the same test could be done in the 25-pair (depressed) position. This can be verified by tracing the circuitry through. A high impedance loop is placed across the pair being tested by employing the bifilar windings 82, 84 of transformer T1 86 in series. This loop goes from one wiper arm 88 of switch 16 through the A contact of switch K7 64, through the A contact of switch K5 60, through windings 82 and 84 in series, through contact B of switch K5 60 and contact B of switch K7 64 to the other wiper arm 90 of switch 16. From the wiper arms 88, 90, of course, the loop is connected across the tip and ring of the selected pair as previously described. The input (verifying) path exists between the two connectors 94 and 96, through contacts C and D of switch K7 64, through contacts C and D of switch K1 52, through contacts C and D of switch K4 58, and thence through the meters 26, 28 to ground via the terminal 34. Note that the neon lamps 66, 68 are respectively placed in parallel paths to receive the incoming signal before passing through the meters 26, 28 (being connected on the other side to the ground potential through the terminal 34) whereby high voltages will be sensed.
Referring now to FIG. 6 in combination with FIG. 3, additional circuitry is disclosed which operates in conjunction with the verifying test procedure, previously described, and which was omitted from the schematic diagram of FIG. 3 between the opposite side of the C contact of switch K5 60 and terminal 34 for purposes of keeping FIG. 3 simple and apparent in its symmetry. The ground start circuit, generally indicated as 106, is an optional item which is included in one embodiment of the present invention. The automatic ground start capability provided in the test apparatus 10 of the present invention by circuitry 106 can be accomplished manually by momentarily shorting the ring R input binding post 32 to the ground (G) binding post 34 or 40. Such approach is, of course, not preferred.
Ground start circuits are ones from which the ground normally present at the central office line equipment has been removed. This type of circuit requires a ground as well as a loop from the field to cause it to operate. Once operated, it will hold on the loop only. An example of a ground start circuit is a paystation. The presence of a proper coin condition (e.g. inserting a coin) causes a ground through a coin control relay to be placed on the line. Ground start circuitry 106 of the present invention automatically senses the absence of the central office ground and placed a ground on the line for purposes of testing. As will be noted, the ground start circuitry 106 can only be activated when the VERIFY HALF-TAP button 60 is depressed causing contact C of switch K5 60 to disconnect from the common input point 80 and connect to the line 108. Voltage to activate the ground start circuitry 106 enters line 108 and passes through a first diode 110 to a second diode 112. Diode 112 is a 33 volt zener diode. That is, it cannot conduct unless 33 volts or greater is present on the anode. Under normal conditions i.e. non-ground start circuits, the presence of the ground at the central office will cause the voltage at the anode of zener diode 112 to be half of the applied voltage, because the anode of zener diode 112 is applied to the line circuit at midpoint. However, if no ground is present, the voltage at zener diode 112 will be in excess of 33 volts and zener diode 112 will start charging capacitor 114 which is connected from the other side of zener diode 112 to ground via terminal 34. When capacitor 114 charges sufficiently, a multi-vibrator, generally indicated as 116 and including the transistors 118 and 120, commences switching back and forth. On the cycle that transistor 120 is "on", capacitor 114 can charge to a value approaching 10 volts. Then, when the cycle changes, transistor 118 forces transistor 122 (connected in series with a current limiting resistor 124 across the zener diode 112 to ground) "on", causing a low resistance ground to be placed from transistor 122 operated through resistor 124 and the load resistor 126 of transistor 118 and onto the line through one half of the coil (winding 82 or 84 of transformer 86). During this cycle, the voltage is reduced at the anode of zener diode 112 and zener diode 112 turns "off". The energy stored in capacitor 114, however, allows transistor 118 to maintain holding transistor 122 "on" for a period long enough to cause the line equipment in the central office to operate and return to ground. The two bifilar windings 82, 84 of transformer T1 86, thereafter act in series as the required "loop" to maintain the seizure when capacitor 114 discharges and allows transistors 118 and 122 to turn "off".
In the ground start circuitry 106 thus described, diode 110 is used to block the circuit from positive voltages. A second zener diode 128 is placed across the multi-vibrator 116 in parallel therewith to limit the circuitry to a maximum of 10 volts. Resistor 130 is connected from the source of transistor 118 to ground to insure that transistor 122 fully turns "off". Resistor 124 is a current limiting resistor which limits the current to transistor 122. Resistors 132 and 134 in combination with capacitors 136 and 138 provide the timing of multi-vibrator 116. Resistor 126, as previously described, as well as resistor 140 are merely load resistors for their respective transistor 118 and 120.
In addition to the specifically described circuits above, it will be noted that, for added flexibility, the preferred embodiment of the present invention, as shown in FIGS. 3 and 6, includes contacts of DIRECT ACCESS swith K1 52 which, when operated, provide a direct path between the input terminals T, R, and G (30, 32, 34) and the 25-pair switch 16 and the single pair cord 48 passing through the 25-pair switch selector 64 whereby the test set can bypass its internal circuitry and provide a selectable switch path between the inputs and outputs for use in connecting other external equipment to the pairs and the cutterpresser device 24. | A portable test set is disclosed for rapid pair identification, polarity determination, and half-tap verification in conjunction with modular testing apparatus employed in splicing cables--particularly cables used in the telephone industry for interconnecting telephone switching systems and subscriber equipment. Switchable meters operating in combination as a single indicator are provided for determining individual line pair conditions prior to execution of simultaneous multiple pair splicing operations to prevent customer inconvenience or loss of service. The test set is adapted for mating with contemporary modular splicing equipment through the interface typically provided therein. The test set is particularly characterized by incorporating no internal power supply as is the usual case in such equipment but, rather, operating totally from voltages present in the cables under test. | 6 |
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