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This is a continuation-in-part application of application having Ser. No. 07/986,785 filed Dec. 8, 1992, now abandoned. Benefit of the earliest filing date of Dec. 8, 1992 is claimed.
FIELD OF THE INVENTION
An improved storage container and means for organizing or storing compact disks in their contaning jewel boxes. More specifically, the present invention provides an improved method and an improved apparatus which allows a lighted viewing area of the compact disc's box, from the cover, rather than the spline.
DESCRIPTION OF THE PRIOR ART
A patentability investigation was conducted and the following U.S. patents were discovered: U.S. Pat. No. 4,802,587 to Armijo et al.; U.S. Pat. No. 306,663 to Larsen; U.S. Pat. No. 4,932,522 to Milovich; and U.S. Pat. No. 5,031,779 to Szenay et al. None of these prior art patents teach or suggest the particular compact disc container and method of this invention.
SUMMARY OF THE INVENTION
The present invention broadly accomplishes its desired objects by broadly providing a versatile compact disc box container or holder for holding a plurality of compact disc container boxes. The compact disc box container or holder comprises a rack means which preferably comprises a pair of opposing longitudinal side supports having a structure defining a plurality of associated and opposed angularly disposed channels. At least one tray member is slidably disposed in opposed channels. A pair of longitudinal lugs is secured to the longitudinal side supports, and at least two end cap members slidably are engaged to the longitudinal lugs. The longitudinal lugs and the end cap members comprise a dove-tail joint in cross section. A stop member is secured to the end cap members. The tray members are each manufactured from a material composition containing fluorescent dyestuffs.
It is another object of the present invention to provide a method for storing compact disc containers such that when stored a portion of the face of the compact disc container is readily seen and illuminated. The method comprises the steps of:
(a) providing a compact disc container having a planar face with informational indicia representing the contents of audio program on a compact disc contained therein;
(b) providing a compact disc holder assembly for holding a plurality of the compact disc containers and for displaying and viewing the informational indicia representing the contents of audio program on a compact disc contained therein; said compact disc holder assembly comprising at least one rack means for supporting the plurality of compact disc containers in a generally upright posture, said racks means comprising at least two longitudinal side supports having a structure defining a plurality of opposed angularly disposed channels; at least two trays slidably disposed in the opposed channels; a pair of longitudinal lugs bound to and traversing the longitudinal side supports; at least two longitudinal end cap members having a structure defining at least two longitudinal recesses for slidably receiving and engaging said longitudinal lugs; said tray members comprising a transparent plastic composition having a dyestuff agent for producing a fluorescent effect;
(c) slidably disposing the compact disc container between said two trays such that said compact disc container is viewably illuminated by the fluorescence effect of the tray member.
It is therefore an object of the present invention to provide a versatile compact disc container box holder assembly and method.
These, together with the various ancillary objects and features which will become apparent to those skilled in the art as the following description proceeds, are attained by this novel versatile compact disc container box holder as shown with reference to the accompanying drawings by way of example only, wherein:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the compact disc box rack;
FIG. 2 is a segmented vertical perspective view of the compact disc box rack taken in the direction of the arrows and along the plane of line 2--2 in FIG. 1;
FIG. 3 is a perspective view of the compact disc box rack with a plurality of angular channels in the side supports of the rack and with one tray member slidably removed from a pair of channels in the rack;
FIG. 4a is a top plan view of the compact disc box rack;
FIG. 4b is a front plan elevational view of the compact disc box rack;
FIG. 4c is a top plan view of one embodiment of the upright end cap used in the compact disc box holder;
FIG. 4d is a side elevational view of the compact disc box rack;
FIG. 5 is an exploded perspective segmented view of several of the compact disc box racks in a lazy-susan holder configuration, without any upright end caps employed for holding the compact disc box racks in a generally upright posture;
FIG. 6 is an exploded perspective view of the compact disc box racks slidably engaging four upright end caps in a lazy-susan holder configuration, with one of the racks in the process of slidably engaging a pair of the upright end caps and with a light being furnished on the inside of the lazy-susan holder for illuminating the racks holding compact disc containers or jewel boxes;
FIG. 7 is a perspective view of two of the compact disc box racks showing a terminating upright end cap and a coupling upright end cap engaged to one of the racks, and a segmented stand for slidably engaging the bottom of one the racks;
FIG. 8 is a top plan view of two of the compact disc box racks coupled together by a pair of terminating upright end caps in a back to back holder configuration, with the dotted line configuration representing the pair of compact disc racks and the end caps;
FIG. 9 is a top plan view of two of the compact disc box racks coupled in a side by side relationship with an intermediate coupling upright end cap and two terminating upright end caps in a linear configuration, with the dotted line configuration representing the compact disc racks and the upright end caps;
FIG. 10 is a top plan view of three of the compact disc box racks and three angled upright end caps in a triangular lazy-susan holder configuration, with the dotted line configuration representing the compact disc racks and the upright end caps;
FIG. 11 is a top plan view of four of the compact disc box racks and four angled upright end caps in a square lazy-susan holder configuration, with the dotted line configuration representing the compact disc racks and the upright end caps;
FIG. 12 is a top plan view of five of the compact disc box racks and five angled upright end caps in a pentagonal lazy-susan holder configuration, with the dotted line configuration representing the compact disc racks and the upright end caps;
FIG. 13 is a top plan view of six of the compact disc box racks and six angled upright end caps in an hexagonal lazy-susan holder configuration, with the dotted line configuration representing the compact disc racks and the upright end caps;
FIG. 14 is a top plan view of eight of the compact disc box racks and eight angular upright end caps in an octagonal lazy-susan holder configuration, with the dotted line configuration representing the compact disc racks and the upright end caps;
FIG. 15 is a partial front elevational view of one of the compact disc box racks, with compact disc containers disposed therein in a fashion such that a substantial part (i.e. top part) of each disc container can be readily viewed to determine the artist(s) of the compact disc without having to view the spline (or edge) of each disc container to determine the artist (s);
FIG. 16 is a perspective view of the number 1 composed of the high-priority florescent dye stuff contained in a transparent plastic; and
FIG. 17 is a perspective view of the letter E composed of the high-priority florescent dye stuff contained in a transparent plastic.
DETAILED DESCRIPTION OF THE INVENTION
Referring in detail now to the drawings wherein similar parts of the invention are identified by like reference numerals, there is seen compact disc box rack holder assembly (see FIG. 6), generally illustrated as 10. The holder assembly 10 comprises a plurality of rack means, generally illustrated as 12, for containing and holding a plurality of compact disc containers, each generally illustrated as 8 (see FIG. 3) and containing a compact disc 9, such that when contained and held a portion of the face of each compact disc container 8 may be readily seen to determine the artist(s) of the compact disc 9 contained in each container without having to view a spline (or edge) 11 of each container. More particularly, each disc container 8 has written or labeled informational indicia 4 thereon which represents the contents of the audio program on the compact disc 9 contained therein (see FIG. 15). With the holder assembly 10 of the present invention, the indicia 4 on the front or planar face of each of the containers 8 may be readily seen without having to look for and/or read any indicia on the spline 11 to determine audio information. When conventional compact disc containers are stored in conventional compact disc holders, the splines or edges of the disc containers have to be read to determine the artist(s) of the compact disc 9. The front or planar faces of the containers are not readily available for viewing without having to physically move the conventional disc containers. With the disc rack holder assembly 10 of the present invention, no splines 11 or edges 11 of the containers 8 have to be read to view and/or determine the artist(s) of the compact disc 9. The holder assembly 10 of the present invention also comprises a plurality of upright end cap means, generally illustrated as 14, for engaging the rack means 12 in a holder configuration.
The compact disc box rack means 12 comprises (see FIG. 3) a pair of opposing longitudinal side supports 22, each formed with a plurality of opposing angularly disposed channels 34 (or openings). A longitudinal lug 32 is engaged to each of the side supports 22 and traverses the longitudinal length of the side supports 22. A back support member 24, a top member 26, and a bottom member 28, are all connected to the side supports 22--22. A plurality of tray members 30 is slidably disposed in the angularly disposed channels 34 (see FIG. 2). The longitudinal lugs 32 define a structure comprising a male dove-tail protrusion joint (in horizontal cross section) as best shown in FIG. 4a. Each tray member 30 comprises a structure that terminates in an angled edge 36, respective to the plane of the tray 30, along the back edge of the tray 30 such that upon disposal in the channels 34 the angled edge 36 flushes with the back 24 of the rack means 12.
Each of the rack means 12 is supported by an upright end cap means 14 which has a number of embodiments. In the embodiment in FIG. 4c, the upright end cap means 14 comprises a structure defining a pair of female dove-tail recesses 42 (in horizontal cross-section), for slidably engaging the longitudinal lugs 32. As best shown in FIG. 4c, the upright end cap means 14 also comprises an arcuate face 43 and an upright back 45 that assist in forming the dove-tail recesses 42.
The compact disc rack holder assembly 10 may be manufactured from or by any suitable material, such as plastic (polyethylene, polypropylene, ABS, PVC, etc.). Preferably, the holder assembly 10, especially each of the rack means 12, is manufactured from a fluorescent transparent plastic such as by way of example only a polymethylmethacrylate sold under the product name LISA VP KL-39402 E 6IR of Bayer Aktiengelsellschaft, Leverkusen, Federal Republic of Germany. More preferably, the holder assembly 10 is manufactured of a light-collecting plastic and/or system, as more particularly described in U.S. Pat. Nos. 4,492,648 and 4,526,705, both of which are fully incorporated herein by reference thereto as if repeated verbatim hereafter. The plastic and/or system contains a dyestuff agent that produces a fluorescent effect. The light-collecting plastic is able to collect and conduct light which results from the extreme clarity of the transparent plastics and the fluorescence of the dyestuffs used, which are evenly distributed throughout each plastic part. Fluorescence is governed by the laws of geometric optics concerning light refraction and total internal reflection when light passes from a medium of higher optical density (the polymer plastic) to one of lower optical density (air). These laws determine that in the plastics used in the present invention to manufacture the rack holder assembly 10, only a small proportion of the fluorescent light can be emitted at the interface between the plastic and the air. Most of it is repeatedly reflected back into the material (total internal reflection) and, in this way, is transmitted through the polymer plastic until it comes to an interface through which it can emerge. Such interfaces are the perimeter edges or other deliberately created "edges" on the plastic to which the collected light can be conducted. The plastics employed in the present invention are colored, transparent polymers with special optical properties which collect or absorb light from their surroundings, conducting it within the material and re-emitting a large proportion of the light in concentrated form at the edges; such as edges 22e of the side supports 22, edge 24e of the back 24, edges 30e and 36e of the trays 30, edges 26e of the top member 26 (see FIG. 1) and edges 28e of the bottom 28. This produces the edge brightness for the holder assembly 10 such that edges 22e, 24e, 26e, 28e, 30e, 36e (etc.) glow luminating the face of the compact disc containers 8 when light hits the back 24, the sides 22--22, the top member 26, and the trays 30, and any other element of the assembly 10 which is manufactured from a transparent plastic containing the dyestuff agent. The edge brightness may be enhanced by the employment of a light 100 that is to glow when electrical cord 102 conducts electricity after a plug 104 is disposed in any suitable electrical outlet. It is to be understood that the planar surfaces of the elements (e.g. trays 30, sides 22, etc.) may also emit some light but the brightest effects will be produced from and at the edges of the elements (e.g. 30e, 22e, etc.)
Referring now to FIGS. 16 and 17 for another feature of the present invention, there is seen indicia matter, generally illustrated as 200, which is manufactured of the plastic and/or the systems containing the dye stuff agent for producing the fluorescent effect, all of which have been immediately set forth with particularity, and which may be placed on the apparatus 10 of the present invention at any suitable location. The indicia matter 200 may be a number, such as the number "1" represented as 210 in FIG. 16, or a letter, such as the letter "E" represented as 220 in FIG. 17, or any other indicia suitable for being placed on the apparatus 10. Edges 210e and 220e of the indicia matter 200 produce light rays 58 when light hits the sides of the indicia 200.
Thus, one of the salient points of the present invention is the employment of a light-collecting system and/or plastic for holding and storing compact disc containers 8 while simultaneously producing novel optical properties on the compact disc containers 8 that result from the incorporation of high-priority fluorescent dyestuffs (as more particularly described in U.S. Pat. Nos. 4,492,648 and 4,526,705 which have been fully incorporated herein as if repeated verbatim hereafter) into the transparent polymers of extreme clarity. As best shown in FIG. 15, the edges (e.g. edges 30e, etc.) produce light rays 58 (or light enhanced rays) to produce a fluorescent effect on the containers 8 and indicia 4. While edges 22e, 24e, 26e, 28e 30e, 36e, are the only edges which have been specifically identified as producing light rays 58, it is to be understood that the spirit and scope of the invention includes any edges of any other elements (e.g. upright end cap means 14) which are produced with a transparent plastic containing the dyestuff agent.
The compact disc holder assembly 10 may be configured in one of several ways, as shown by way of example only in FIG. 5 and FIG. 6 as a lazy-susan configuration 48. The lazy susan configuration 48 comprises four (4) rack means 12, four (4) upright end cap means 14, a top cover (plate) member 50, a bottom cover (plate) member 52 and a lazy-susan carousel assembly 54. The bottom cover member 52 supports all of the racks 12 to prevent all of the same from sliding away from the four (4) upright cap means 14 by the longitudinal lugs 32 sliding out of the recesses 42. The top cover 50 covers the tops of the racks 12 and the upright end cap means 14. It is apparent that the cover (plate) member 50 and the bottom (plate) member 52 may be manufactured from a transparent plastic containing a fluorescent dyestuff agent.
The compact disc holder assembly 10, when configured as a lazy-susan type holder may take on a variety of shapes as best shown in FIGS. 10 through 14. FIG. 10 shows the compact disc holder assembly 10 in a triangular configuration. FIG. 11 shows the compact disc holder assembly 10 in a square configuration. FIG. 12 shows the compact disc holder assembly 10 in a pentagonal configuration. FIG. 13 shows the compact disc holder assembly 10 in an hexagonal configuration. FIG. 14 shows the compact disc holder assembly 10 in an octagonal configuration. Obviously, the rack 14 (especially the lugs 32) and the upright end cap means 14 (especially the recesses 14) may be conveniently configured to produce any of the variety of shapes shown in FIGS. 10-14.
The compact disc holder assembly may be additionally configured as a standing rack 58 (refer to FIGS. 7 through 9); and as best shown in FIG. 7, comprises at least one of said rack means 12, at least two of the upright end cap means 14, and a stop or bottom member 44. The stop member 44 is engaged to the bottom of the end cap means 14 which in this embodiment of the invention is square or rectangular shape in configuration and may have longitudinal bores 80 wherethrough bolts, screws (not shown) or the like may pass to mount to an upright or free standing surface, such as a wall or the like. Alternatively, as further shown in FIG. 7 there is seen a stand means 60 having a recess 62 to slidably receive and retain the bottom member 44 for supporting the compact disc holder assembly 10 in a generally upright position. The standing rack 58 may also be configured with a pair of the rack means 12 engaged by the end cap means 14 with the back 24 of one of the rack means 12 to the back 24 of another of the rack means 24 (refer to FIG. 8).
While the present invention has been described herein with reference to particular embodiments thereof, a latitude of modification, various changes and substitutions are intended in the foregoing disclosure, and it will be appreciated that in some instances some features of the invention will be employed without a corresponding use of other features without departing from the scope of the invention as set forth. | A compact disc box container assembly for holding a number of compact disc container boxes and for displaying, illuminating, and viewing the facial informational indicia of the disc boxes. The holder comprises a pair of opposing longitudinal sides defining a structure with angularly disposed channels, at least two tray members, and at least a pair of end caps slidably engaged to the longitudinal sides. The composition of the composing material includes a fluorescent dyestuff for the illumination of the disc boxes, especially from the edges of the elements that make-up the assembly. | 0 |
FIELD OF THE INVENTION
The present invention relates to methods for detecting executable code which has been altered.
BACKGROUND OF THE INVENTION
Providing secure software in today's existing distributed computing environment is a major problem for software development vendors. Experienced hackers can intercept the distribution or the installation of otherwise secure software and alter its performance in some way Alterations may include, by way of example only, the bypassing of automatic licensing checks, the insertion of malicious computer viruses, and others.
Software vendors have reacted by trying to prevent alterations in a variety of ways, such as distributing the software in executable format, encrypting installation dates which are checked by the software upon execution against an expiration date associated with a license agreement, password protecting the installation and/or execution of the software, and others. Yet, hackers have become extremely adept and are now capable of tracing the executable code to a particular point in the execution sequence and modifying return values located in the executable code which effectively bypass or alter many of the checks installed by the vendors. Furthermore, by altering the executable code to effectively bypass various required checks, hackers are able to bypass the validation of encrypted dates and any requisite passwords, thereby allowing unfettered execution of the software without being subject to any licensing limitations imposed by the software vendor. Moreover, once the software has been modified the hackers can create a permanent fix by patching the operating system or the executable code itself and then reinstalling the software on the operating system.
Further, some operating system vendors have attempted to install checks within the operating system itself to validate that software provided by the vendor is in fact secure. However, this has proved problematic since upgrades and new releases of software often require a user to get frequent patches and updates to the operating system from the vendor. This becomes frustrating to the user, and often if the user neglects to obtain the requisite patch and attempts to run new software, the new software cannot be validated, thereby creating potential security breaches in the operating system. Moreover, hackers have developed fixes which include modifying the software associated with the operating system itself to overcome these lower level checks instituted by the vendors.
Also, many of today's adept programmers have developed techniques to alter the operation of an executable, by modifying the image of the executable which is resident in the memory of the operating system. In this way, any checks being performed upon initiation, or even later, of the executable are bypassed altogether, since initiation has concluded once the image is fully resident in the operating system. This allows programmers to alter the image of the executable without detection. Yet, if the operating system is restarted, such as with a reboot operation or other operations, the original unaltered image of the executable will be fully restored and the programmer will again have to alter this image to achieve his/her desired result.
Of course, a hacker may actually create a separate piece of software which would modify the image of the executable code in memory such that any self-checking code is automatically disabled by the separate piece of software. In such a scenario, this would assist the hacker in defeating checks performed after the executable initially begins execution, or during any runtime checks which the executable may perform.
In today's distributed computing environment where access is in theory available to the entire world nearly instantaneously, a hacker's modification to a vendor's software may permit global unauthorized use of the vendor's software. This creates an incentive to not purchase a valid copy of the vendor's software and may substantially impact the overall viability of the vendor's product in the marketplace. Furthermore, as more and more unauthorized versions become available the likelihood of malicious modifications becomes more frequent which could impact the reputation of the vendor in the marketplace for all the vendor's products. Further, the vendor often finds itself expending unnecessary human resources in addressing problems associated with unauthorized modifications to its software, since support staff may be contacted by users of unauthorized versions of the software for assistance with problems. Accordingly, the ability to ensure software provided by a vendor is secure and reliable is of paramount importance in today's global access computing environment which is presently being fueled by the pervasiveness of the Internet and the World Wide Web (WWW).
SUMMARY OF THE INVENTION
Accordingly, an aspect of the invention is to provide methods of detecting executable code which has been altered while in memory. By performing a calculation against the executable image (e.g., code and data) during the initial loading of the executable code to an operating system to generate an initial score, and by performing subsequent calculations to generate subsequent scores associated with the executable image, a determination may be made as to whether the executable code has been altered. The initial score may be compared to subsequent computed scores randomly, periodically, or by manual selection of a user. A user may include any entity represented by the operating system, which by way of example only, includes a mouse selected option by an end user or another executable code requesting scores to be compared at any particular point in time.
As one skilled in the art will readily appreciate, subsequently compared scores to the initial score allows a software vendor to ensure that the current executable code (e.g., program instructions and data used by the instructions) residing in the resident memory of the operating system is the correct image of the executable code, as it was originally loaded or presented to the operating system. Moreover, the software vendor may ensure that any executable code which is subsequently modified and saved cannot be reloaded since the reloaded executable code will be associated with a different score than the originally loaded score. In this way, the software distributed and being supported by the software vendor may be continually validated for authenticity and alterations are detectable and reportable to the software vendor.
Additional aspects, advantages and novel features of the invention will be set forth in the description that follows and, in part, will become apparent to those skilled in the art upon examining or practicing the invention. The aspects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out in the appended claims. To achieve the foregoing and other aspects and in accordance with the purpose of the present invention, methods of detecting executable code which has been altered are provided.
A method of validating executable code resident in an operating system having executable instructions is provided, comprising receiving a score associated with an executable code when the executable code is initially loading into an operating system, wherein the score is saved. Further, a subsequent score is received which is associated with the executable code and the subsequent score is compared to the initial score to determine if the executable code has been altered.
Furthermore, a method of disabling executable code which has been modified without authorization having executable instructions is provided, comprising receiving a score associated with an executable code and receiving one or more subsequent scores associated with the executable code. Moreover, the executable code is disabled if the initial score is not equal to any of the subsequent scores.
Finally, a method of authenticating executable code resident in a memory having executable instructions is provided, comprising acquiring a score associated with an executable code which was established when the executable code was first loaded into a memory of an operating system. Next, a subsequent score associated with the executable code is received while the executable code is in the memory and the subsequent score is compared to the initial score.
Still other aspects of the present invention will become apparent to those skilled in the art from the following description of an exemplary embodiment, which is by way of illustration, one of the exemplary modes contemplated for carrying out the invention. As will be realized, the invention is capable of other different and obvious aspects, all without departing from the invention. Accordingly, the drawings and descriptions are illustrative in nature and not restrictive.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, incorporated in and forming part of the specification, illustrate several aspects of the present invention and, together with their descriptions, serve to explain the principles of the invention. In the drawings:
FIG. 1 depicts a flow diagram of a method for validating executable code;
FIG. 2 depicts a flow diagram of a method for disabling executable code which has been altered; and
FIG. 3 depicts a flow diagram of a method of authenticating executable code.
DETAILED DESCRIPTION
The present invention provides methods for detecting executable code which has been altered. One embodiment of the present invention is implemented in NOVELL's NetWare operating system environment using the C or C++ programming language. Of course other operating systems, and programming languages (now known or hereafter developed) may also be readily employed.
Software is developed, distributed, and executed in a variety of different formats. Typically, software is distributed to consumers by vendors in an executable form or binary form. The executable form is also the format required to run the software on a computing device. The source form of the software is often not distributed or made available to the consumer, as this is in a human readable format which is used in developing the software, and making it available would allow even the most novice programmer to substantially modify the software and create an infinite number of executable forms of the software.
The industry refers to the source form of the software as the source code, while the executable or binary form of the software is often referred to as the executable code or binary code. A compiler will translate a source code into an executable code. As will be readily apparent to those skilled in the art, modifications to the source may result in permitting the derivative forms of the source to perform differently than what was originally intended by the software vendor. Moreover, although modifications to the executable or binary form of the source is more difficult, it is still, nevertheless, a real threat.
Moreover, executable code is not usually readable to humans, although some adept programmers have developed methods of reading and understanding at least some portions of the executable code. By understanding the execution sequence and key portions of the executable code, programmers have been able to modify the executable code to cause the software to perform in a way that is not consistent with how the software is intended to function. For example, alteration of the execution sequence may permit one to bypass important licensing aspects of the vendor's products. Furthermore, some malicious programmers make alterations by inserting computer viruses into the executable code, which may substantially damage the reputation of the vendor and potentially damage non vendor software on a consumer's computing device. As a result, most attempts made by vendors to protect licensing, copyright, trademark, and other rights have been circumvented by programmers with the skill to trace and modify the executable code, which is distributed with the software product by the vendor.
Furthermore, often software which is to be installed on a computing device is packaged in installation scripts, which permit the automatic installation of the executable code to the operating system of a consumer's computing device. Often, the installation scripts will ensure that the requisite directories and files are present for the proper execution of the executable code. Moreover, these installation scripts often register the executable code with the operating system such that each time the operating system is initiated, the executable code is loaded into the resident memory of the operating system and thereby made available for execution by the consumer or some other program on the computing device.
In an exemplary embodiment of the present invention, the software is compiled into an executable form, and the executable form of the software is then distributed in whatever manner desired by the software vendor, such as by way of example only, direct download, on a separate computer readable medium for installation, and others. Although as one skilled in the art will appreciate, the software may also be distributed in an encrypted format, or in a source code format, and other formats without detracting from the present invention. Moreover, the software may take on one or more formats prior to installation. Further, some software is provided in a format which is both its source format and its executable format, such as by way of example only, software provided in interpretive languages, such as PERL, and others. Correspondingly, executable code, as used herein, includes any format of the software (e.g., program instructions, data, scripts, control files, parameters, and the like) which is used for execution on a computing device.
Either during the installation of the executable code or shortly after the initial installation of the executable code, a set of executable instructions is run against the distributed executable code to generate a score associated with the executable code. In one embodiment, the score is the result of performing a calculation against the executable code. By way of example only, a calculation which may be used to generate a unique score from the executable code is a checksum calculation. Checksum calculations are well known in the art, and a variety of different calculations may be used, some standard and some ad hoc.
By way of example only, a checksum calculation may be performed by treating the data which comprises the executable code as nothing more than a series of numbers which are adjacent to one another, such that every 16 bits in the executable code is an integer. All numbers are then summed together to generate a total, this total is the score which is associated with the unique executable code. Periodic or random subsequent calculations performed against the executable code, to generate subsequent scores, may then be compared to the initial score generated. Any variation in the initial score to a subsequently generated score will provide an indication that the data associated with the executable code has been altered. Further, it is well known by those skilled in the art that some generation algorithms (e.g., hash algorithms) will perform better than other algorithms (i.e. generate scores with a higher probability for uniqueness). Moreover, it is extremely unlikely that the data associated with the executable code may have been altered and yet still generate the same score as the initial score.
Accordingly, as one skilled in the art will readily appreciate, by comparing a score associated with an initial calculation against periodic or random subsequent calculations, a good indication as to whether the executable code has been altered in anyway may be ascertained. If the executable code has been altered, the alteration may be trapped and recorded. Moreover, the software vendor may be notified electronically that the executable code has been altered in some unauthorized fashion. Further, if alteration is detected the executable code may be disabled or unloaded from the resident memory of the operating system, thereby preventing the effective use of the altered executable code.
In an exemplary embodiment a set of executable code responsible for performing one or more calculations against the executable code resides as one or more low level routines within the operating system. In this way, the execution associated with these instructions will be difficult to detect and alter. Moreover, the calculation or scoring set of executable instructions may be used to validate one or more executable codes. Accordingly, a typical installation script loading a vendor's executable code may check to see if the calculation or scoring set of executable instructions are on the computing device to which installation is desired. If the calculation or scoring set of executable instructions are not available, then the installation script will install them.
Furthermore, distributed executable code may optionally be altered such that it cannot run successfully unless the calculation or scoring set of executable instructions is running within the resident memory of the operating system. In this way, a programmer may not terminate the execution of the calculation or scoring set of executable instructions and then proceed to alter the executable code of the software vendor. Moreover, any manual termination of the calculation or scoring set of executable instructions may be detected and cause the concurrent termination of all executable codes associated with the calculation and scoring set of executable instructions which are being terminated. Thus, a programmer will not easily be able to eliminate the execution of the calculation or scoring set of executable instructions.
FIG. 1 illustrates a flow diagram of one embodiment for a method of validating executable code. Initially a set of executable instructions depicted by FIG. 1 identifies an executable code in step 10 which is to be installed, or was very recently been installed. The data which represents the executable code is read and a calculation, such as a checksum calculation, is performed against the data. The result of the calculation is a score which is acquired in step 20 .
The score may then be stored in step 30 . Storage may occur in a variety of ways, such that a unique reference to the executable code, with the initially acquired score retrievable both from volatile and non-volatile memory. For example, storage may be temporary in the random access memory (volatile memory) associated with the execution of the executable instructions depicted by FIG. 1 , and storage may also be permanent to a computer readable medium, such as a hard disc (internal) or a floppy diskette (external), or others. In this way, should the computing device or operating system housing the executable instructions depicted by FIG. 1 terminate the executable instructions, such as when power is terminated or interrupted in some way, the executable instructions will still be operative to detect the executable code reference and the initial score on a non-volatile computer readable medium when the executable instructions are restarted after power is restored.
In step 50 , the calculation performed against the executable code to generate a score is completed periodically or randomly. Moreover, the calculation may be requested manually by another application or by a user. Generating scores randomly or periodically may be configured by the software vendor providing the executable code. Performing operations periodically or randomly are well known in the art and may be implemented within the operation itself or may be initiated by external operations. For example, the executable instructions depicted in FIG. 1 may include logic to read a file having control information, wherein the control information dictates when a calculation is to be performed or initiated against a specific executable code. Alternatively, an external set of executable instructions could be configured to periodically or randomly call a calculation against a specific executable code. By way of example only, two such external sets of executable instructions providing the above referenced utility in the UNIX operating system environment is a “cron” utility and the “at” command.
Once a subsequent score is obtained, the initially generated score associated with the executable code is compared to the newly acquired executable code in step 60 . If the scores are not identical, then the executable code has been altered in some way since the initial score was taken. Unauthorized modifications my be reported in step 40 and the owner of the executable code may be notified electronically as well. Some comparisons producing different scores may in fact be authorized by the software vendor. For example, a software vendor may provide bug fixes to the executable code or patches associated with the executable code. In these instances, the user may be required to reinstall the software and the authorized reinstallation will be detectable by the executable instructions of FIG. 1 and a new initial score will be generated and stored with the newly provided executable code. Alternatively, the software vendors may provide files or passwords which permit or interface with the executable instructions of FIG. 1 so as to permit the generation of a new initial score.
If the subsequent score associated with the executable code does not match the initial score and there is no valid authorization detected, then the executable code may be unloaded from the resident memory of the operating system within which it resides, or significant features associated with the executable code may be disabled in step 70 . Disabling only certain features may be attractive to the software vendor, since even an unauthorized version may have some independent utility which the vendor wants to permit or exploit. For example an image viewer with editing capabilities may have only the editing functions disabled, while still permitting advertisements and viewing capabilities to be operational for the user.
FIG. 2 depicts one method for a flow diagram of a method of disabling executable code which has been altered. Initially a set of executable instructions depicted by FIG. 2 receive a score in step 80 associated with a specific executable code. The initial score is acquired during the loading process of the executable code or shortly thereafter. However, the initial score may be permissibly modified and regenerated if permitted by the software vendor. Such permission may occur in a variety of ways, such as, by way of example only, special tags embedded in the executable code which are detected and associated with vendor authorization, new installation with slight name changes associated with the executable code, passwords supplied by the software vendor, and others.
Once an initial score is obtained, one or more subsequent scores are received in step 90 . Each subsequent score is compared in step 100 to detect if the initial score and the subsequent score are the same. If the comparison is the same (step 110 ), then the executable code associated with the initial score and the subsequent score is permitted to load or remain in the memory of the operating system (step 120 ) within which it is to execute or is presently executing, and the comparison is recorded and registered to a log or history file in step 150 , where it may later be used or audited by the vendor or by utilities provided by the vendor. Such recording may include trapping and saving a variety of system provided variables, such as, by way of example only, user name, date, time, and others.
If the initial score and the subsequent score vary, a determination is made as to whether the variation is a valid condition (e.g. vendor authorized), in which case a new initial score is saved. If the variation in the scores is not valid, the executable code is disabled in step 140 . The executable code may also be removed from the operating system's memory in step 130 . Unauthorized variations are reported in step 160 . Reporting may occur, by way of example only, by electronically notifying the vendor/owner of the software, recording information in a log or history as discussed above, and others.
FIG. 3 depicts one embodiment for a flow diagram of a method of authenticating executable code. An initial score is acquired in step 170 , the score being associated with a specific executable code and acquired by performing a calculation against the executable code when the executable code was initially loaded or shortly thereafter, or if the vendor permitted the modification of the initial score as discussed previously. Moreover, the calculation performed against the executable code, in an exemplary embodiment, is a checksum calculation.
Sometime after an initial score is obtained, one or more subsequent scores are acquired in step 190 . In step 180 , the initial score and the subsequent scores are compared, and if different (step 210 ) the executable code is suspended from operation or disabled in step 220 , and the failed comparison is reported along with relevant system information (e.g. date, time, user, and others) in step 230 . Moreover, comparisons and subsequent scores may be performed each time a user or an application attempts to launch the executable code for use in step 200 . In this way, checks against the executable code by generating scores may be obtained every time the code is attempted to be used, periodically, or randomly. Moreover, a combination of comparisons and score generations may occur. For example, a subsequent score may be acquired each time the executable code is launched for use and then may also be acquired randomly or periodically while the executable is in use. In this way, any alteration to the executable code, after its initial launch may be detected while the executable code is in use. As one skilled in the art will readily appreciate, this will permit changes to the image of the executable code to be detected with the executable code is executing.
The foregoing description of an exemplary embodiment of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive nor to limit the invention to the precise form disclosed. Many alternatives, modifications, and variations will be apparent to those skilled in the art in light of the above teaching. Accordingly, this invention is intended to embrace all alternatives, modifications, and variations that fall within the spirit and broad scope of the attached claims. | Methods of detecting executable code which has been altered are provided. Upon an initial loading of an executable code a calculation is performed to generate a score associated with the executable code, the initial score is retained. Subsequently, one or more additional calculations are performed on the executable code to generate subsequent scores. Any subsequent score not matching the initial score indicates the executable code has been altered in some way. If alteration has occurred, then the executable code is partially or completely disabled and optionally unloaded from the operating system within which it resides. Moreover, an owner associated with the altered executable code may be notified, or other events may be triggered as a result of scores which when compared are not equal. Calculations may be performed on the executable code randomly, at pre-defined intervals, or upon a specific request. | 6 |
FIELD OF THE INVENTION
[0001] The invention relates generally to mobile communications. In particular, the invention relates to methods, computer programs, apparatuses and radio network nodes for getting a timing advance.
BACKGROUND OF THE INVENTION
[0002] The cellular wireless applications have become more and more diverse and bandwidth-demanding. Thus, there is a constant need for increasing the bandwidth for users. In addition to high bandwidth-demand some applications have also very high requirement for quality of service (QoS). One example of this is video call, wherein the transferred data amount is high and there is a need to keep the video fluent in order to provide pleasant user experience.
[0003] Because of this commercial operators have invested to their networks for increasing the capacity. However, the licensed spectrum, supervised by the operators, is a scarce resource of which amount along with the current policy of using the licensed spectrum may not be enough to support huge number of cellular devices and higher QoS requirement traffic in the future. Thus, there is a constant need for finding improvements to the bandwidth and QoS.
[0004] One solution to the above mentioned problem is to use unused parts of radio spectrum. One example of unused part of radio spectrum is the white spaces between TV channels.
[0005] The TV white space (TVWS) bands are the unused parts of radio spectrum—the TV channels—in the 54-698 MHz range. In the US, for example, the Federal Communications Commission (FCC) has approved the regulated use of the white spaces between and among the unused analog TV channels for unlicensed devices. The potential use of TVWS has been investigated widely in the recent years due to their available large bandwidths at suitable frequencies for different radio applications. In the US, the FCC has regulated licensed or license-exempt TV bands for the secondary-system applications, such as cellular, WiFi and WiMax, on TV Band Devices (TVBD). The highly favorable propagation characteristics of the TV broadcast spectrum, as compared to the 2.4 or 5 GHz bands, allow for wireless broadband deployment with greater range of operation with the ability to pass through buildings, weather, and foliage at lower power levels. Thus, the TV white spaces could be used to provide ubiquitous coverage for municipal wireless networks.
[0006] There are multiple available TV channels in the broadcast television frequency bands at 54-60 MHz (TV channel 2 ), 76-88 MHz (TV channels 5 and 6 ), 174-216 MHz (TV channels 7 - 13 ), 470-608 MHz (TV channels 14 - 36 ) and 614- 698 MHz (TV channels 38 - 51 ), which can be used for TVBD. FCC has defined following requirements for different TV band device types.
[0007] 1. Fixed Device.
Operating from fixed location registered to WS database. Geo-location/database access required. Max 1 W transmission power (4 W radiated power (EIRP)). Operating on unoccupied channels between 2 and 51 . Can't operate on the first adjacent channels to TV stations.
[0013] 2. Personal/Portable Devices—Modes II/Mode I.
Can't operate below channel 21 . Do not need to register to WS database. Operating on unoccupied channels between 21 and 51 . Max 100 mW radiated power (EIRP). (40 mW close to TV station's service area). Mode II: Geo-location/database access required. Mode I: Geo-location/database access not required. A mode II device can accesses to a TV bands database either through a direct connection to the Internet or through an indirect connection to the Internet by way of fixed TVBD or another Mode II TVBD, to obtain a list of available channels. A mode II device may select a channel itself and initiate and operate as part of a network of TVBDs, transmitting to and receiving from one or more fixed TVBDs or personal/portable TVBDs. A Mode II device must check its location at least once every 60 seconds while in operation
[0023] 3. Sensing Only Device.
Use spectrum sensing to determine a list of available channels. Max 50 mW radiated power (EIRP). (40 mW close to TV station's service area). Operating on unoccupied channels between 21 and 51 .
[0027] Timing advance is needed in various mobile communication networks for controlling uplink transmissions from a user equipment (UE) to a base station. In the following Long Term Evolution (LTE) networks are used as an example in describing prior art and the problem, however, the same problem may be present also in different network technologies. In LTE networks timing advance is needed so that uplink transmissions from different users arrive at the eNodeB essentially within the cyclic prefix. eNodeB is a radio base station in control of all radio related functions in the fixed part of the LTE system. Such uplink synchronization is needed to avoid interference between the users with uplink transmissions scheduled on the same sub-frame. The timing advance value is measured from Random Access Channel (RACH) transmission when UE does not have a valid timing advance, that is, the uplink for the UE is not synchronized. Timing advance is also needed when LTE user equipments transmit to eNodeB on TVWS due to the large coverage.
[0028] In conventional LTE system timing advance is obtained by doing RACH due initial access, RRC connection re-establishment, handover, downlink data arrival or uplink data arrival.
[0029] One problem of doing RACH to get riming advance is that one contention-based RACH may collide with another one, which decreases the spectrum efficiency. Furthermore, there are channels which can only be used by portable devices and sensing devices such as channels which are the first adjacent channels to TV stations. In these channels, only user equipment transmissions to eNodeB and to other user equipments are allowed. In other words these are downlink disabled channels. So doing RACH on these downlink disabled channels is impossible.
[0030] Thus, there is a need to find a solution to get timing advance on TVWS due to its specific characteristics and regulatory requirements such as on down- link disabled channels.
SUMMARY OF THE INVENTION
[0031] The invention discloses a method for obtaining timing advance. Timing control procedure is needed for uplink transmissions in several communication networks. Some networks and bands have physical and regulatory limitations for obtaining timing advance value in conventional manner. One example of these limitations is disabled downlink channel in TV white spaces. The present invention provides an arrangement for obtaining timing advance value in a situation wherein the use of downlink channel is disabled.
[0032] The method comprises receiving uplink data at a user equipment for uplink data transmission, requesting the location of a base station from a database, receiving the location of the base station from the database and calculating a timing advance value based on the locations of the user equipment and the base station. After calculating the timing advance in the method uplink data is transmitted using the calculated timing advance.
[0033] In an embodiment of the invention a timing advance resolution timer is used. It is determined whether the user equipment receives timing advance command or scheduling signaling from the base station. If the response is not received before the timing advance timer is expired timing advance value is inquired from at least one neighboring user equipment.
[0034] In an embodiment of the invention the timing advance value is chosen from the closest neighboring user equipment. Instead of the closest neighboring user equipment the timing advance value may be chosen based on an average of timing advance values of neighboring devices, selecting randomly one received timing advance value, or any other similar suitable method. If timing advance value is not available from neighboring user equipments random access channel transmission may be performed in order to get timing advance value in some other downlink channel.
[0035] In an embodiment of the present invention the user equipment is an LTE-device. In a further embodiment of the present invention the LTE-device is a mode II device. In an embodiment of the present invention the user equipment is operating on TV white spaces. In an embodiment of the invention the database is a TV white space database.
[0036] In a further embodiment of the invention the method further comprises requesting a timing advance value from a base station as a response for location change. In a further embodiment of the invention the method further comprises sending the timing advance value to neighboring devices as a response for the request from the base station.
[0037] In an embodiment the present invention is implemented as an apparatus comprising receiving and sending unit, location determination unit configured to request and receive the location of the base station from a database and processing unit configured to calculate a timing advance value based on the locations of the user equipment and the base station. In an embodiment of the invention receiving and sending unit is configured to transmit uplink data using the calculated timing advance. In an embodiment of the invention the apparatus further comprises a timing advance resolution timer. In an embodiment of the invention the apparatus is configured determine whether the receiving and sending unit receives timing advance command or scheduling signaling from the base station. If the timing advance resolution timer has expired and a timing advance value has not been received, the apparatus is configured to inquire timing advance value from at least one neighboring user equipment. In an embodiment of the invention the apparatus further comprises an inquiring timer. In a further embodiment the apparatus is configured to choose the timing advance value from the closest neighboring user equipment, wherein the choosing comprises receiving information from neighboring devices and calculating the distance between the user equipment and each of the neighboring devices respectively. Instead of the closest neighboring user equipment the timing advance value may be chosen based on an average of timing advance values of neighboring devices, selecting randomly one received timing advance value, or any other similar suitable determination. In an embodiment of the present invention is configured to perform random access channel transmission when the timing advance value is not received from a neighboring user equipment.
[0038] In an embodiment of the invention the apparatus is an LTE-device. In a further embodiment the apparatus is a chipset. The chipset is suitable for use in a communications device. In a further embodiment of the invention the apparatus is operating on TV white spaces. In an embodiment of the present invention the database is a TV white space database.
[0039] In a further embodiment of the invention the apparatus is further configured to request a timing advance value from a base station as a response for location change. In a further embodiment of the invention the apparatus is further configured to send the timing advance value to neighboring devices as a response for the request from the base station.
[0040] In an embodiment of the invention the invention is implemented as a computer program comprising code adapted to cause the method mentioned above. In an embodiment of the invention the computer program is stored on a computer readable medium.
[0041] The invention as disclosed above provides a solution to the problem of obtaining timing advance value in downlink disabled channels. In addition to this it reduces the need for random access channel transmission and thus reduces overhead and overall load in the network.
BRIEF DESCRIPTION OF THE DRAWINGS
[0042] The accompanying drawings, which are included to provide a further understanding of the invention and constitute a part of this specification, illustrate embodiments of the invention and together with the description help to explain the principles of the invention. In the drawings:
[0043] FIG. 1 a is a block diagram according to a use scenario of an embodiment of the present invention,
[0044] FIG. 1 b is a block diagram of a user equipment of FIG. 1 a,
[0045] FIG. 2 is a method according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0046] Reference will now be made in detail to the embodiments of the present invention, examples of which are illustrated in the accompanying drawings. It must be understood that even if LTE is used as an example technology in the following example, the solution is applicable to all communication networks having similar problem.
[0047] In FIG. 1 a is a block diagram according to a use scenario of an embodiment of the present invention. In the figure a base station 10 is communicating with three user equipments 11 - 13 . In the example of FIG. 1 a the base station is eNodeB of an LTE network and also a fixed device in TVWS. Each of the user equipment 11 - 13 are LTE enabled devices that are also Mode II devices in TVWS. These devices can communicate with an external database 14 . In this example the database is TVWS database.
[0048] FIG. 1 b discloses a user equipment according to the present invention. In the example of FIG. 1 b the user equipment 11 comprises sending and receiving unit 15 , location determining unit 16 , processing unit 17 , inquiry timer 18 and timing advance resolution timer 19 . The functionality of these components are explained in the following description, wherein an example of a method according to the present invention is disclosed.
[0049] In FIG. 2 a method according to the present invention is disclosed. For the sake of the clarity the method is applied to the exemplary application scenario disclosed in FIG. 1 a and 1 b . In the method it is assumed that user equipments UE1-UE3 are LTE user equipments in mode II. Fixed device is an LTE eNodeB. User Equipments can get the location of the eNodeB through a TVWS database.
[0050] In the example of FIG. 2 there is UL data arrival to the UE1. Thus, UE1 needs to get a timing advance value for the UL transmission, step 20 . First UE 1 requests eNodeB's location information from TVWS database, step 21 . When eNodeB's location is known UE 1 can calculate a rough timing advance value for UL transmission based on the own location and eNodeB's location, step 22 . The UE 1 uses this rough timing advance for UL transmission, step 23 . At the same step UE1 sets timing advance resolution timer and the timer starts to decrease. If the timing advance value is not accurate but eNodeB can adjust it by timing advance command, then UE1 will receive timing advance command or scheduling signal within the timing advance resolution timer and it could just continue transmission, step 24 . If UE gets timing advance command or scheduling signaling from eNodeB in step 24 , then eNodeB adjusts timing advance by timing advance command, step 25 . If timing advance is not accurate and is not in the adjustment range, UE1 will not receive TA command and scheduling signaling. Then expiry of the timing advance resolution timer is expected, step 26 .
[0051] After expiration of the timing advance resolution timer UE1 may send out inquiring signaling to request its neighbor UEs, which are within one timing advance step distance, to share their timing advance values with it. At the same time an inquiring timer is set, step 27 . The sent inquiring signaling includes UE1's location information. After receiving UE1's inquiring signaling, its neighbor UEs such as UE2 and UE3 will calculate their distances with UE1 based on their locations. If their distances with UE1 are all beyond one timing advance step distance, they will not send their timing advance values to UE1. If UE2 and UE3 are within one time advance step distance and willing to share their own TA values with UE1, they will send TA feedback signaling to UE1, which includes their timing advance values and their location information. After UE1 receives two timing advance values from UE2 and UE3, it will choose one timing advance value, step 29 . In this example, after calculating the distances with UE2 and UE3, UE1 chooses the timing advance value from UE3 which is nearer, step 211 . If UE2 was nearer UE1 would have chosen timing advance value from UE2, step 210 .
[0052] If UE2 or UE3 do not send their timing advance value, or there is no other user equipments available, and inquiring timer expires at step 212 , UE1 may do contention-based RACH. In this case, it is possible that UE1 gets the RACH response from a different frequency band/channel on which DL transmissions are allowed, step 213 .
[0053] In a further embodiment of the present invention the method is performed in advance. In order to get timing advance on time, UE1 can get a timing advance value based on its distance with eNodeB once its location changes for one timing advance step distance. It can also send out inquiring signaling to request timing advance from neighbor UEs within one timing advance step distance. Once eNodeB updates one UE's timing advance value, it can request this UE to voluntarily share its new timing value with its neighbor UEs. Its neighbor UEs within one timing advance step distance can decide to update their timing advance value or not.
[0054] The exemplary embodiments can include, for example, any suitable servers, workstations, PCs, laptop computers, personal digital assistants (PDAs), Internet appliances, handheld devices, cellular telephones, smart phones, wireless devices, other devices, and the like, capable of performing the processes of the exemplary embodiments. The devices and subsystems of the exemplary embodiments can communicate with each other using any suitable protocol and can be implemented using one or more programmed computer systems or devices.
[0055] One or more interface mechanisms can be used with the exemplary embodiments, including, for example, Internet access, telecommunications in any suitable form (e.g., voice, modem, and the like), wireless communications media, and the like. For example, employed communications networks or links can include one or more wireless communications networks, cellular communications networks, 3G communications networks, Public Switched Telephone Network (PSTNs), Packet Data Networks (PDNs), the Internet, intranets, a combination thereof, and the like.
[0056] It is to be understood that the exemplary embodiments are for exemplary purposes, as many variations of the specific hardware used to implement the exemplary embodiments are possible, as will be appreciated by those skilled in the hardware and/or software art(s). For example, the functionality of one or more of the components of the exemplary embodiments can be implemented via one or more hardware and/or software devices.
[0057] The exemplary embodiments can store information relating to various processes described herein. This information can be stored in one or more memories, such as a hard disk, optical disk, magneto-optical disk, RAM, and the like. One or more databases can store the information used to implement the exemplary embodiments of the present inventions. The databases can be organized using data structures (e.g., records, tables, arrays, fields, graphs, trees, lists, and the like) included in one or more memories or storage devices listed herein. The processes described with respect to the exemplary embodiments can include appropriate data structures for storing data collected and/or generated by the processes of the devices and subsystems of the exemplary embodiments in one or more databases.
[0058] All or a portion of the exemplary embodiments can be conveniently implemented using one or more general purpose processors, microprocessors, digital signal processors, micro-controllers, and the like, programmed according to the teachings of the exemplary embodiments of the present inventions, as will be appreciated by those skilled in the computer and/or software art(s). Appropriate software can be readily prepared by programmers of ordinary skill based on the teachings of the exemplary embodiments, as will be appreciated by those skilled in the software art. In addition, the exemplary embodiments can be implemented by the preparation of application-specific integrated circuits or by interconnecting an appropriate network of conventional component circuits, as will be appreciated by those skilled in the electrical art(s). Thus, the exemplary embodiments are not limited to any specific combination of hardware and/or software.
[0059] Stored on any one or on a combination of computer readable media, the exemplary embodiments of the present inventions can include software for controlling the components of the exemplary embodiments, for driving the components of the exemplary embodiments, for enabling the components of the exemplary embodiments to interact with a human user, and the like. Such software can include, but is not limited to, device drivers, firmware, operating systems, development tools, applications software, and the like. Such computer readable media further can include the computer program product of an embodiment of the present inventions for performing all or a portion (if processing is distributed) of the processing performed in implementing the inventions. Computer code devices of the exemplary embodiments of the present inventions can include any suitable interpretable or executable code mechanism, including but not limited to scripts, interpretable programs, dynamic link libraries (DLLs), Java classes and applets, complete executable programs, Common Object Request Broker Architecture (CORBA) objects, and the like. Moreover, parts of the processing of the exemplary embodiments of the present inventions can be distributed for better performance, reliability, cost, and the like.
[0060] As stated above, the components of the exemplary embodiments can include computer readable medium or memories for holding instructions programmed according to the teachings of the present inventions and for holding data structures, tables, records, and/or other data described herein. Computer readable medium can include any suitable medium that participates in providing instructions to a processor for execution. Such a medium can take many forms, including but not limited to, non-volatile media, volatile media, transmission media, and the like. Non-volatile media can include, for example, optical or magnetic disks, magneto-optical disks, and the like. Volatile media can include dynamic memories, and the like. Transmission media can include coaxial cables, copper wire, fiber optics, and the like. Transmission media also can take the form of acoustic, optical, electromagnetic waves, and the like, such as those generated during radio frequency (RF) communications, infrared (IR) data communications, and the like. Common forms of computer-readable media can include, for example, a floppy disk, a flexible disk, hard disk, magnetic tape, any other suitable magnetic medium, a CD-ROM, CD±R, CD±RW, DVD, DVD-RAM, DVD±RW, DVD±R, HD DVD, HD DVD-R, HD DVD-RW, HD DVD-RAM, Blu-ray Disc, any other suitable optical medium, punch cards, paper tape, optical mark sheets, any other suitable physical medium with patterns of holes or other optically recognizable indicia, a RAM, a PROM, an EPROM, a FLASH-EPROM, any other suitable memory chip or cartridge, a carrier wave or any other suitable medium from which a computer can read.
[0061] While the present inventions have been described in connection with a number of exemplary embodiments, and implementations, the present inventions are not so limited, but rather cover various modifications, and equivalent arrangements, which fall within the purview of prospective claims. | Timing control procedure is needed for uplink transmissions in several communication networks. Some networks and bands have physical and regulatory limitations for obtaining timing advance value in conventional manner. One example of these limitations is disabled downlink channel in TV white spaces. The present invention provides an arrangement for obtaining timing advance value in a situation wherein the use of downlink channel is disabled. | 7 |
BACKGROUND INFORMATION
1. Field of the Invention
The present invention relates to an apparatus and method for preventing condensation in machines processing web-like material. More particularly, the present invention relates to an apparatus and method for preventing condensation in a printing press by controlling temperatures in an area of a printing unit of a printing press.
2. Description of the Related Art
In print shops and press testing facilities there has been a problem that on high-speed machines, condensation occurs on those safety elements, such as finger guards, vital to protecting the press operating staff as well as on other sub-systems of the printing press. Condensation on a guard can be, for example, in the form of droplets on the surfaces which can collect to form drops dripping either onto the surface of the web-type material to be printed upon or into the printing unit itself, thereby causing print defects and other undesirable conditions. Condensation below the web-type material can cause print defects as well, for example, when droplets drip onto surfaces of vibrator rollers or the like of a lower printing unit.
Even on other printing unit components such as shields, rails, frame parts or tail tuckers, condensation may also occur in the form of droplets dripping on the web or on components of the ink train, thus posing a risk for maintaining print quality. For example, condensation of water on the surface of print unit rolls, especially the rolls in the dampening system of a printing press, can have a detrimental effect on the water feed in the lithographic printing process--condensed water added to the dampening solution on a roll can exceed the capacity of the nip resulting in excess water build-up and excess water in the nip can result in unstable water feed, thereby reducing print quality. Indeed, drips onto the web can cause direct lithographic errors and condensation on a roll, especially dampener rolls, can destabilize the lithographic process.
It is an object of the present invention to prevent defects on printed material from a printing press due to condensation. It is another object of the present invention to maintain the air temperature surrounding a selected area of a printing press to prevent condensation.
SUMMARY OF THE INVENTION
According to an exemplary embodiment of the present invention, undesired condensation in a selected area of a printing press, for example a dampener system, is controlled by, for example, controlling the air temperature surrounding the dampener system by cooling and heating the air (thereby also changing the humidity of the air) such that the temperature difference between the components of the dampener system and the surrounding air has a desired value and creates a substantially isothermal condition.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and other features of the present invention will become apparent to those skilled in the art upon reading the following description of preferred embodiments of the invention in view of the accompany drawing, wherein:
FIG. 1 is an exemplary illustration of an isothermal dampener system according to the present invention; and
FIG. 2 is an exemplary flow chart for a method of creating a substantially isothermal condition according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 illustrates an isothermal dampener system according to the present invention. In a conventional dampening system, such as described in U.S. Pat. Nos. 5,592,880 and 5,520,113, which are expressly incorporated herein by reference, excess water may form on the dampening system roller due to the high relative humidity and temperature differential from the atmosphere to the roller surface. The excess water in the dampener due to condensation may cause the delivery of dampening solution to, for example, the printing plate to be inconsistent.
In the isothermal dampener system according to the present invention, however, more consistent delivery of dampening solution to the printing plate is provided by, for example, controlling the temperature of the dampening system rollers, the temperature of dampening fluid and the temperature of the air in the area of the dampening system to be substantially equal via a temperature control unit 110, as illustrated in FIG. 1.
For example, air temperatures slightly less than or slightly greater than the temperature of the dampening fluid and dampening roller are acceptable. This would allow, for example, a small amount of condensation or evaporation which will not cause lithographic problems. Thus, for air temperatures slightly lower than the temperature of the dampening fluid and the dampening roller surface temperature, a low and acceptable level of evaporation of dampening fluid into the air can occur. Similarly, for air temperatures slightly greater than the temperature of the dampening fluid and dampening roller surface temperature, a low and acceptable level of condensation onto the roller surface can occur. Thus, the result of maintaining temperatures in such an acceptable range will result in, for example, a consistent delivery of dampening solution to the printing plate.
As shown in FIG. 1, an exemplary isothermal dampening system 100 according to the present invention includes a temperature control unit 110 connected to a conventional printing unit dampening system 105. The printing unit dampening system 105, may include, for example, a multiplicity of rollers and cylinders via which a dampening solution is applied to a printing form, such as a printing plate on a print cylinder of a conventional web-offset printing press. The printing unit dampening system 105 may be enclosed or isolated from ambient air conditions by, for example, enclosing the dampening system 105 or print unit in a box or similar structure. The entire printing unit including the isothermal dampening system 100 could also be enclosed or isolated from ambient air conditions if desired.
The temperature control unit 110 may include, for example, a programmable control unit 110a, such as a conventional microprocessor based control unit, that receives, for example, a signal T A representing ambient air temperature of the print unit dampening system 105, a signal T F representing the dampening fluid temperature, a signal T wo representing the roller cooling water outlet temperature and a signal T WI representing the roller cooling water inlet temperature.
Also connected to the print unit dampening system 105 is the dampener fluid temperature control unit 115 which may include, for example, a pump and related plumbing to circulate the dampening fluid to the dampening system 105, a tank to hold a reservoir of dampening fluid, and a heater/chiller unit to control the temperature of the dampening fluid temperature by, for example heating or cooling the tank of dampening fluid via conventional methods to maintain a constant temperature of the dampening fluid.
A roller cooling water temperature control unit 120 is also connected to the print unit dampening system 105 and may include, for example, a pump and related plumbing to circulate fluid through dampener system rollers, a tank to hold a reservoir of, for example, water, and a heater/chiller unit to control the temperature of the water into the dampener roller(s). The air temperature control unit 125, also connected to the print unit dampening system 105, may include, for example, a fan to circulate air through the enclosed unit (e.g., the dampening system 105), a heater to increase the air temperature as directed by the temperature control unit 110 and a chiller to decrease the air temperature as directed by the temperature control unit 110, for example, using a conventional heating, ventilation and air conditioning (HVAC) system.
The programmable control unit 110a of the temperature control unit 110 receives the input signals T A , T F , T wo and T WI and outputs a control signal determined as a function of the input signals and a reference temperature T REF . The signals T A , T F , T WO and T WI can be provided from either a sensor measuring each of the respective values in the print unit dampening system 105 or, for example, from a sensor measuring each of the values in the dampener fluid temperature control unit 115 or the roller cooling water temperature control unit 125, respectively. For example, the temperature of the dampener fluid, which flows in both the dampening system 105 and the dampener control unit 115, could be measured at either the print unit dampening system 105 or at the dampener fluid temperature control unit 115, and then provided to the temperature control unit 110.
T REF represents a reference temperature for the isothermal dampener system according to the present invention. T REF can be, for example, a predetermined value, such as a temperature based on the experience of the printing unit operator to provide optimal operating conditions, such as a 72° F. running temperature for the dampener system. Alternatively, T REF can be determined, for example, as a function of the ambient air temperature in the print unit dampening system 105 so that T REF is set to be equal to the ambient air temperature. The programmable control unit 110a thus receives the signals T A , T F , T WO , and T WI and then outputs a control signal to the respective components of the isothermal dampener system 100 according to the present invention based on the desired temperature for the system, T REF , and the current temperatures in each component of the system.
For example, the control signal could be the value of T REF which, when received by a particular component, would cause that component to be cool down or heat up, as appropriate, to achieve the value of T REF . For example, the air temperature control unit 125, the dampener fluid temperature control unit 115 and the roller cooling temperature control unit 120 each receive the control signal and then respond thereto e.g., adjust their respective operating conditions to cool down or heat up as necessary, via, for example, their respective heater/chiller units and circulation systems. Alternatively, the temperature control unit 110 can send an individual heat or cool control signal to each component of the isothermal dampener system 100 instead of a single control signal to each component, the individual control signal being determined as a function of T REF to cause the appropriate temperature adjustment in the receiving unit.
FIG. 2 illustrates an exemplary process for creating an isothermal condition according to the present invention. For example in step 200, the ambient air temperature, T A , is determined. In step 210, the temperature of the dampening fluid, T F , is determined. In steps 220 and 230, the temperature of the roller cooling water outlet and inlet, respectively, are determined. In step 240, the reference temperature, T REF , is determined, either based on the ambient air temperature or a predetermined value. As will be apparent to those skilled in the art, steps 200 to 240 can be performed in any sequence or could even be performed simultaneously. In step 250, the output signal is determined as a function of at least one of T A , T F , T WO , T WI and T REF and provided to components 115, 120 and 125 which can adjust their respective temperatures in response to the control signal so that a substantially isothermal condition is maintained for the print unit dampening system 105.
Accordingly, the control signal from the temperature control unit 110 according to the present invention causes the temperatures of the dampening system rollers, the dampening fluid and the air in the area of the dampening system to be controlled so that the temperatures are substantially equal e.g., so that a substantially isothermal condition exists, each of the components of the isothermal dampening system 100 having a similar and constant temperature. For example, the fan of the air temperature control unit 125 can be controlled in response to the control signal to circulate air through the print unit dampening system 105, the circulated air being heated or cooled by the heater or chiller of the air temperature control unit 125, if necessary. Similarly, the heater or chiller of the roller cooling water temperature control unit 120 and the dampener fluid temperature control unit 115 can be controlled as a function of the control signal to control the temperature of the roller cooling water and dampening fluid, respectively (via the respective reservoir tank and pumping systems) that is circulated through the isothermal dampener system 100 so that the temperatures of the dampening system rollers, the dampening fluid and the air in the area of the dampening system are substantially equal.
As noted earlier, air temperatures slightly above or below the temperature of the dampening fluid and the temperature of the dampening roller surfaces provide a low and acceptable level of evaporation of dampening fluid or condensation onto the roller surface. Accordingly, by measuring the temperature of the dampening liquid, dampening roller cooling water and ambient air temperature and varying the air and component temperatures by, for example, cooling or heating the air or fluids in the system according to the present invention, the temperature difference between the components in the isothermal dampening system and the air becomes minimal. Thus, the result of maintaining temperatures in such an acceptable range manner will result in minimal condensation in the system and, for example, a consistent delivery of dampening solution to the printing plate. | An apparatus and method for preventing condensation in a selected area of a printing press, for example a dampener system, by, for example, controlling the air temperature surrounding the dampener system by cooling, heating or changing the humidity of the air such that the temperature difference between the components of the dampener system and the surrounding air has a desired value. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a divisional of U.S. patent application Ser. No. 10/767,877 filed Jan. 29, 2004, now U.S. Pat. No. 7,223,347 which claims the benefit of priority of U.S. Application No. 60/443,429 filed Jan. 29, 2003 and U.S. Application No. 60/502,383 filed Sep. 12, 2003, all of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
The present invention relates to a method for removing backwash from a filter apparatus.
SUMMARY OF THE INVENTION
In embodiments of the invention, a backwash removal method is provided for removing backwash fluid during circulating and scrubbing of compressible media in a filter apparatus by air-elevating backwash fluid to a “highest” localized level above a lower surface level to drive the backwash fluid in a backwash removal device adjacent and contiguous to the localize elevated portion of backwash. In some embodiments, the process of the invention includes using one or more troughs that receive and remove backwash fluid. In further embodiments of the invention, the backwash process of the invention operates in a filter apparatus with a movable housing.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic cross-sectional view of a single filter apparatus of the present invention showing a flexible housing for containing filter media in an embodiment of the present invention.
FIG. 2 is a schematic cross-sectional view of a filter apparatus of the present invention during initial filling with fluid to be filtered.
FIG. 3 is a schematic cross-sectional view of a filter apparatus of the present invention as the hydraulic head becomes greater upstream than in the downstream flow and the hydrostatic pressure of the unfiltered fluid compresses the flexible housing in an embodiment of the invention.
FIG. 4 is a schematic cross-sectional view of a filter apparatus of the present invention as influent level reaches an optional overflow pipe in an embodiment of the invention.
FIG. 5 is a schematic cross-sectional view of a filter apparatus of the present invention during backwash operation in an embodiment of the invention.
FIG. 6 is a schematic view of fiber being reduced from spools and bound for cutting into fiber media bundles in an embodiment of the invention.
FIG. 7 is a front perspective view of a filter media bundle in an embodiment of the invention.
FIG. 8 is a cross-sectional view of a filter media element including a hog ring/binding wire crimping and holding the center of the filter media bundle fibers in an embodiment of the invention.
FIG. 9 is a schematic cross-sectional view of a concentric bi-component fiber in an embodiment of the invention.
FIG. 10 is a schematic cross-sectional view of an eccentric bi-component fiber in an embodiment of the invention.
FIG. 11 is a schematic cross-sectional view a multi-component fiber in an embodiment of the invention.
FIG. 12 is a schematic cross-sectional view depicting first and second compression zones of compressible filter media in a filter media housing in an embodiment of the invention.
FIG. 13A is a schematic cross-sectional view of a filter media housing including uncompressed filter media and a backwash removal device in an embodiment of the invention.
FIG. 13B is a schematic top plan view of a backwash removal device along line I-I of FIG. 13A in an embodiment of the invention.
FIG. 14A is a schematic top plan view of a plurality of filter units within a large fluid containment in an embodiment of the invention.
FIG. 14B is a schematic cross-sectional view of a plurality of filter units along line II-II of FIG. 14A .
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides an apparatus and method for filtering fluids with compressible filter media contained in a flexible housing. In the described embodiments, fluid outside the housing compresses the housing and filter media; however, it will be appreciated that a variety of external forces may be applied to the outer housing and compressible media to achieve the objectives of the invention in other embodiments. It will also be appreciated that although the invention is described in embodiments for top to down filtering of fluid, the apparatuses and components described herein may be positioned such that the filtration may occur in other directions, and repositioning is within the scope of the invention.
The present invention thus provides improved filtration, and is particularly adapted for the filtration of stormwater, drinking water and wastewater. Those skilled in the art will further appreciate that in other embodiments the present invention is adapted for use with a variety of fluids and filtering applications.
Referring to FIG. 1 , in an embodiment of the present invention a filter apparatus 10 includes an outer fluid container 15 . Outer fluid containment housings include concrete containers, earthen basins, natural water features (including a lake), and like environments in which fluid to be filtered may be contained. An influent pipe 20 provides fluid to be filtered into the outer container 15 . It will be appreciated that the influent pipe 20 may be located in a variety of positions (such as above or below the top of the filter) and or/include a plurality of influent pipes 20 .
Within the outer container 15 an upright filter media housing 25 is provided. FIG. 1 depicts the filter media housing 25 comprising a flexible membrane in both expanded and compressed embodiments to demonstrate compressibility of the housing. The top of the filter media housing 25 includes an upper perforated plate 30 to allow fluid to be filtered into the housing, as well as backwash fluid out of the housing, while retaining the filter media within housing (such as during backwash processes subsequently described).
A housing base 35 secures the filter media housing 25 at the bottom of the outer container 15 .
In one embodiment, the base may include baffles 40 that direct filtered fluid to an effluent pipe 45 carrying filtered fluid from the filter housing 25 out of the containment 15 . The baffles 40 may also direct air and make-up water to the center of lower perforated plate 50 during backwashing operations ( FIG. 5 ).
Referring to FIGS. 14A and 14B , in other exemplary embodiments, the containment 15 may include a plurality of filter units 11 wherein the base may be a wall of an effluent channel/conveyance 45 A or a piping network underlying one or more filter units 11 . In such embodiments, the channel wall or piping serves as the base to support one or more filter units 11 is an upright position within the outer containment 15 . The integrated filter unit 11 into the conveyance 45 A may be provided without baffles 40 .
In a large containment environment as shown in FIGS. 14A and 14B , the underlying effluent conveyances (or piping) 45 A may all connect to a larger effluent conveyance 45 B for carrying off filtered fluid. In other embodiments underlying conveyances 45 A may be directed to other desired locations and conveyance points.
FIGS. 14A and 14B , also show that one or more backwash pumps 72 may be provided for removing backwash fluid from the containment 15 following the backwash process (subsequently described).
In embodiments utilizing a plurality of filter units 11 , it will be appreciated that the containment 15 may include a large basin, natural feature, manmade containments and the like, where a large quantity of fluid is to be filtered. It will also be appreciated each of the filter units 11 includes compressible media 60 and a filter media housing 25 and operates as subsequently described with reference to a single filter unit.
Referring again to FIG. 1 , between the upper plate 30 and base 35 , the lower perforated plate 50 allows filtered fluid to exit the flexible housing 25 . The lower perforated plate 50 also supports filter media 60 ( FIG. 2 ) within the housing 25 .
With further reference to FIG. 2 and FIGS. 7-11 , compressible filter media 60 is housed within the housing 25 between the upper perforated plate 30 and lower perforated plate 50 . Although the filter bundles disclosed in U.S. Pat. No. 5,248,415 to Masuda et al. and U.S. Patent Application Publication No. US2003/0111431 are particularly adapted for use as filter media 60 in the present invention, a variety of compressible fibrous filter elements may be used.
In certain embodiments, the fibrous media 60 of the present invention improves upon the prior art through the use of multi-component fibers where two or more synthetic materials are used in the same fiber to achieve the physical characteristics such as specific gravity, resilience, chemical resistance, stiffness, fiber diameter, and the like. In other embodiments, the filter media fiber may further include components with specifically desired performance characteristics such as specific pollutant removal capabilities. For example, oleophilic fiber components may be used in embodiments for attracting oil from fluid being filtered or hydrophobic fibers may be used to encourage water filtration. Those skilled in the art will appreciate that a wide variety of other combinations of components in the filter media may be adapted for use in the present invention depending on the desired performance the type of fluid and pollutants being filtered.
In one embodiment to achieve a chemically resistant fibrous lump of low resilience and lower specific gravity, the fiber is manufactured with a nylon inner core and polypropylene outer cover.
In another embodiment to obtain a heavier, more resilient lump 61 ( FIGS. 7 and 8 ), the fiber is manufactured using a polyester inner core with a polypropylene sheath.
Referring to FIG. 9 , in one embodiment the multi-component fiber is a bi-component fiber, wherein an inner fiber 65 and an outer fiber 67 (sheath) are provided/extruded in a generally concentric configuration.
Referring to FIG. 10 , in another embodiment the components are generally eccentric with the inner component 65 being off-center. In such embodiment, subsequently described, the eccentric configuration permits heating of the fiber to produce crimping based on the resultant heat distortion.
It will be appreciated that in alternative embodiments a plurality of inner fibers 65 may be contained in a sheath 67 , such as shown in FIG. 11 . In such embodiments, the plurality of inner fibers 65 may be the same or different component materials. It will also be appreciated that one or more additional outer sheaths could be provided in alternative embodiments to achieve specific pollutant removal as well as exhibit desired physical characteristics.
In various embodiments, core and sheath materials may include any combination of the following, or other synthetic fibers: polyester (PET), coPET, polylactic acid (PLA), polytrimethylene terephthalate, polycyclohexanediol terephthalate (PCT), polyethylene napthalate (PEN); high density polyethylene (HDPE), linear low density polyethylene (LLDPE), polyethylene (PE), polypropylene (PP), PE/PP copolymer, nylon, polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE) and polyurethane.
Referring to FIG. 6 , the fibers used as filter media 60 are initially in the form of loosely packed elongated fibers 70 on spools 75 .
With continuing reference to FIG. 6 , several bundles of elongated fibers 70 are brought together from the spools 75 using a reducing device 80 . The device 80 reduces the overall size of the fibers while a hog ring fastener/binding wire 85 or other similar clamp is applied. After the clamps are applied, the fiber bundles are cut at cut lines 90 between each clamp 85 to form a fibrous lump 61 ( FIGS. 7 and 8 ).
In embodiments of the invention, the multi-component fibers can be crimped mechanically and/or by heating.
A mechanical crimping machine is used in one method. Following extrusion, the fibers are mechanically crimped along the length of the fibers to produce crimped fiber. A second method is to produce the multi-component fiber 65 such that the core materials are placed eccentrically from the sheath 65 ( FIG. 10 ). When heat is applied, the fiber materials distort differently resulting in a helically shaped crimp. The amount of heat applied is dependent on the fiber materials.
Referring again to FIG. 2 , during initial filling, fluid 22 to be filtered enters from the influent pipe 20 and fills the void 28 between the outer container 15 and flexible housing 25 . The air inlet 90 is off. The drain 95 is closed.
With continuing reference to FIG. 2 , initial compression of the filter media is adjustable and can be set by the level of fluid and media inside the filter media housing 25 at the beginning of the filter run. After backwashing (see FIG. 5 and related description), the media is in a relatively uniform suspension with density equal to the number of filter media bundles 61 per volume of fluid within the flexible membrane 25 . A lower fluid level inside the flexible membrane 25 will result in a greater density of filter media 60 and thus a greater initial compression when the void space 28 begins to fill and the flexible membrane 25 compresses the filter media 60 . A higher fluid level left inside the flexible membrane 25 at the beginning of the filter cycle will result in a lower initial compression. Initial compression is shown in FIG. 2 . During this initial filling, it will be appreciated that the flexible housing 25 is relatively expanded until the hydrostatic pressure outside the housing 25 exceeds the pressure within the housing 25 .
With further reference to FIGS. 3 and 12 , fluid 22 rises above the upper perforated plate 30 of the flexible membrane housing 25 , the fluid 22 enters the top perforated plate 30 for filtering by the filter media 60 . The fluid being filtered 22 passes downward through the filter media 60 with particulates being removed from the fluid. It will be appreciated that, in general, larger particulates are removed nearer the top of the filter bed with smaller particulates removed deeper in the media bed and as solids begin to bridge the voids between the media fibers a matting takes place resulting in removal of both fine and larger particles in the upper media zone ( FIG. 12 ). It will also be appreciated that less compression with media open to the fluid being filtered 22 results in the upper zone of the media bed and more compression results in the lower zone. Because of the compression zones, the filter bed becomes more effective in removing a larger amount of particulates per unit of media and protect the finer particulates from passing through the filter. The compression differential described above between the upper and bottom zones of the media bed is created in the initial compression developed after backwashing or during initial filter operation.
With continuing reference to FIG. 12 , initial compression shows the lower filter media bed 60 B to be compressed inward by the filter media housing 25 . The upper filter media bed 60 A is relatively uncompressed as the housing 25 , in embodiments where the housing is a flexible membrane, remains tight and relatively inflexible at the upper portion of the housing 25 between upper plate 30 and a taper point 27 .
In other embodiments the filter media housing 25 may include a plurality of components to achieve the similar effect of multiple compression zones. For example, the upper portion of the housing 25 may comprise a rigid element connected to a lower membrane (lower portion of housing 25 ). The upper filter media 60 A in such embodiment would be uncompressed from the external fluid as the rigid upper portion would not flex inward. The flexible lower portion of the filter membrane would be compressible by the outer fluid to generate compressed lower bed 60 B.
In still other embodiments, the housing 25 could include a lower housing portion with hinged plate walls instead of a flexible membrane. In such embodiments, the hinged wall could be provided with a hinge near taper point 27 , wherein the upper portion of the housing 25 would be a relatively rigid component. Such walls could be provided in a variety of shapes, including flat wall plates with leak-resistant membranes or materials joining one plate to the next plate. Sliding mechanisms may also be used for a portion of the housing to compress inward. It will be appreciated that all such embodiments permit the external fluid pressure to compress the lower portion of the housing and the lower filter media bed 60 B inward.
In embodiments where the housing 25 is flexible, it may be constructed of single or multi-ply membranes of chlorosulfonated polyethylene (Hypalon), polyvinyl chloride (PVC), rubber, viton, polypropylene, polyethylene, vinyl, neoprene, polyurethane and woven and non-woven fabrics. In embodiments where rigid materials are used, such as those including an upper rigid portion or including pivotable or sliding housing walls, construction materials could include steel, stainless steel, other metals, reinforced and unreinforced plastics. It will be appreciated, however, that the filter media housing 25 may be constructed of any suitable material depending on the desired filtering use, types of fluids being filtered, desired corrosive characteristics and the like.
It will also be appreciated that although the present invention is shown in embodiments with external fluid pressure generating compressive force against the housing 25 and filter media 60 , other external forces may also, or additionally, be used to compress the lower filter media bed 60 B. For example, in other embodiments, the side walls of the housing 25 may be actuated in an inwardly pivotable or sliding manner through mechanical, electrical, hydraulic and similar operation. In other embodiments, inflatable components may be provided external to the housing and inflated in a balloon-like manner to press against the housing and compress the filter media.
Referring again to FIG. 12 , the top surface of the filter media bed 60 includes space 62 (see also FIGS. 2-4 ) that is open and untouched by the upper perforated plate. In such embodiment, the upper filter media zone 60 A remains uncompressed by not only the housing 25 , but also avoids external top to down compression from the upper plate 30 because of spacing 62 . It will also be appreciated that the initial compression with relatively uncompressed upper filter media bed 60 A with an open surface and the compressed lower filter media bed 60 B will result in greater particulate penetration than if the upper filter media bed 60 A were compressed or the entire bed were compressed. Finer particulates may therefore be captured in the lower media bed 60 B as greater penetration is achieved. It is thus an object of the present invention to maximize fluid filtering efficiency.
Referring further to FIGS. 3 and 4 , as filtration proceeds and more particulates are removed, the hydraulic head differential across the filter becomes greater ( FIG. 3 to FIG. 4 ) causing greater compression in the lower zone 60 B to prevent smaller particulates from passing through. There is also a slight upheaval of upper media zone 60 A as the lower zone 60 B compresses to allow more particulates to enter the filter media 60 . Compression of the filter media 60 , as described with reference to FIGS. 3 and 4 , thus improves filtering as increasingly smaller and more particulate is removed in the filter media bed 60 .
In embodiments of the invention, the flexible housing 25 shape is also generally wider at the upper portion than at the lower portion of the housing 25 . It will be appreciated that in such embodiments, less filter media 60 is required at the bottom as the filter bed narrows to direct the fluid out of the housing 25 and the fluid 22 being filtered is “cleaner” toward the bottom. Further, the generally tapered embodiment provides additional filter benefits as the media is more loosely packed near the more “open” upper portion and is more densely packed nearer the bottom portion of the housing.
In other embodiments, it will be appreciated that in addition to or instead of tapering housing shapes, different compression levels may be created by higher media concentrations with lower inner fluid levels. Different filter materials and combinations of materials with desired physical properties may also be used to achieve different compression levels, including the layering of filter media with different densities, compressibility or other desired physical and performance characteristics to achieve a desired filter bed that may include one or more zones.
FIG. 3 shows the hydraulic head in the upstream portions outside the flexible housing 25 becoming greater than the downstream hydrostatic pressure. The hydraulic head differential is due to both the flow stream through the filter media 60 and the build-up of particles on the filter media 60 , resulting in increasing upstream fluid level as solids are removed ( FIGS. 3 and 4 ). As the hydrostatic pressure outside the filter media housing 25 becomes greater than the hydrostatic pressure inside the housing 25 , the housing 25 is further compressed inward, thereby further compressing the filter media 60 . In embodiments of the invention, the housing 25 and filter media 60 are compressed in a direction non-parallel, including generally perpendicular in some embodiments ( FIGS. 2-4 and 12 ), to the direction of the fluid flow through the filter media. And as also shown in FIG. 12 , and previously described, a plurality of compression zones may be established, such as lower portion of the filter media bed 60 B being compressed to remove finer particulates and protect the filter media bed 60 from particle breakthrough.
Referring to FIG. 4 , an embodiment of the invention is shown when the filtration cycle has reached its latter stages and/or during a period of peak upstream fluid flow. The latter stage of the filtration cycle is reached when the filter media 60 captures its maximum particle load, and the depth of fluid 22 over the top of the upper perforated plate 30 reaches it maximum fluid level.
In one embodiment of the invention, when the fluid 22 over the filter apparatus 10 reaches it maximum fluid level, closing the influent 20 stops the filter cycle. In this embodiment the backwashing cycle ( FIG. 5 ) is initiated.
In another embodiment of the invention where an overflow pipe 100 is provided, the filter cycle continues whereby fluid 22 is both filtered through the media bed 60 and a portion of the fluid bypasses the filter and is discharged from the outer housing 15 along with the filtered effluent 45 . It will be appreciated that filtration of wet weather flows, such as treatment of stormwater or treatment of wet weather discharges from sewer systems, can be designed to remove a specific particle load according to a desired need for a particular event, and after the load is reached or the design flow rate is reached, excess flows and excess particle loads may be discharged from the filter.
FIG. 5 shows the filter media 60 being backwashed to remove particulate build up. During a backwash operation fluid entry from the influent pipe 20 is stopped. Make-up water 23 is introduced into the filter effluent pipe 45 or to an open-close connection valve to the outer section of the housing base portion 35 . A backwash outlet, such as a backwash pump discharge 105 connected to a backwash pump 72 ( FIG. 14A ), can be used to remove the backwashed particles from the containment housing 15 or the backwashed fluid can be removed from the containment 15 by opening a drainpipe 95 . During backwash the fluid level within the containment housing 15 is lower than the water level within the filter media housing 25 causing the housing 25 to expand.
In the backwash cycle, an air inlet 90 , provides air from a blower at the base portion 35 or under the lower perforated plate 50 . It will be appreciated that the backwashed fluid containing the concentrated particulates from the fluid to be filtered 22 is typically transferred to a sanitary sewer system for further treatment, removed by vacuum vehicle equipment for transport to other facilities for further process or by further processing the backwash fluid on-site by other concentrating and dewatering processes.
The air from the air inlet 90 enters the center section of the base 35 and rises through the center of the lower perforated plate 50 and up through the center of the filter media 60 . The upward center airflow causes the filter media 60 to circulate within the expanded filter media housing 25 during the washing cycle. Circulation of the filter media 60 causes the media 60 to collide with the upper perforated plate 35 and with other media bundles 60 , helping particulates to dislodge. The lower specific gravity of the air/fluid mixture or the hydraulic head of the backwash water within the housing 25 causes the fluid level within the housing 25 to rise and flow over the upper perforated plate 30 into the void 28 inside of the outer container 15 and outside the housing 25 . The backwash fluid exits containment 15 by either gravity drainage through drain 95 or pumping through outlet 105 .
Another embodiment, shown in FIGS. 13A and 13B , includes backwash removal device 200 having troughs 201 , placed on the upper perforated plate 30 . In this embodiment, troughs 201 form a donut-shape around the center of the air inlet on the upper perforated plate 30 . The troughs 201 receive the backwash fluid with concentrated particulates as the backwash fluid rises above the perforated plate 30 (through the action of centrally directed air) and is directed through the radial troughs 201 to the void 28 , thus minimizing particulate recirculation during the backwash mode. It can be appreciated that the quicker the backwash fluid is separated from the circulating media, the less make-up water is required to clean the filter and the shorter the backwashing cycle time. It can also be appreciated that water level in the center of the upper plate 30 is at the highest level caused by the central rising air and this hydraulic head is used to drive the backwash fluid through the radial toughs 201 into the void 28 for removal.
In another embodiment, a drain 95 is provided at the bottom of the outer container 15 . The drain 95 can also be opened to remove fluid from inside the outer container 15 , such as following backwashing. Further, the void 28 between the outer container 15 and housing 25 can be cleaned, and the drain 95 opened to remove the cleaning fluid. It will be appreciated that a plurality of drains 95 may also be provided.
In another embodiment, the backwash removal device 200 can be designed with troughs 201 being enclosed, for example, using pipes to carry backwash water out of the outer containment 15 . It can be appreciated that in certain outer containment structures such as earthen basins with permanent lower water levels or natural water features (such as lakes), the outer containment 15 would not be drained and it may be desired that backwash water be discharged outside of the outer containment 15 . It can be further appreciated that in this application the compressible media housing 25 may be actuated inwards or outwards by an inflatable balloon or similar alternative method as described previously. It can be further appreciated that in an application where the outer containment 15 is a natural water feature with a fixed water level, the fluid inlet to the filter may be closed when backwashing occurs.
Accordingly, while the invention has been described with reference to the structures and processes disclosed, it is not confined to the details set forth, but is intended to cover such modifications or changes as may fall within the scope of the following claims. | A filter media backwash removal method and device for transporting backwash fluid and solids away from re-entering a housing containing circulating filter media. | 1 |
BACKGROUND OF THE INVENTION
This invention relates to a driving mechanism for a three-position electrical switch comprising a jump-drive sub-assembly having a switching shaft which is rotatable between ON, OFF and EARTH switching positions, and a storage drive sub-assembly having a disconnecting spring which releases its stored spring force when a fuse is blown or an open circuit trip has occurred.
Existing driving mechanisms for three-position electrical switches require large operating forces. Additionally, high breaking forces are required when a circuit is interrupted by a blown fuse. Furthermore, existing storage drive sub-assemblies take up a large amount of space. Also, a switching operation from ON to OFF can be carried out only by the storage drive sub-assembly, and not by the jump drive sub-assembly (see for example instructions for use for closed circuit installations of the NSM type from October 1969, Brush Switch Gear Limited England).
SUMMARY OF THE INVENTION
The present invention has been developed primarily, though not exclusively, to provide a driving mechanism for a three-position electrical switch which requires low operating and breaking forces, is small, can be switched via the storage drive sub-assembly from ON to OFF when a fuse is blown or when an open circuit trip has occurred, and can be switched via the jump drive sub-assembly when operated manually.
In general, the invention features, in one aspect, a driving mechanism for a three-position electrical switch having:
a jump-drive sub-assembly having a switching shaft which is rotatable between ON, OFF and EARTH switching positions;
a pivotable actuator operable to rotate the switching shaft between its switching positions;
a spring arrangement coupled with the actuator and operable to store spring energy upon rotation of the actuator in either direction from a mean position;
a detent arrangement coupled with the switching shaft and with the spring arrangement;
a circumferentially spaced arrangement of latches disposed around the switching shaft and engageable with the detent arrangement in order to hold the switching shaft in any one of its switching positions;
a release arrangement coupled with the actuator and operable, upon rotation of the actuator from the mean position through a predetermined angle, to disengage the detent arrangement from the latch arrangement and thereby allow the stored spring energy to act upon the switching shaft to rotate the latter rapidly to the ON position or to the EARTH position depending upon the direction of rotation of the actuator; and
a storage drive sub-assembly coupled with the switching shaft and having a disconnecting spring which is operable to release a stored spring force when a fuse of a fusing arrangement is blown or when an open circuit trip has occurred.
wherein the switching shaft is operable automatically by the storage drive sub-assembly when a fuse is blown or when an open circuit trip has occurred, and the switching shaft is operable manually via the jump drive sub-assembly.
In general, the invention features, in another aspect, a driving mechanism for a three-position electrical switch, having;
a jump-drive sub-assembly having a switching shaft which is rotatable between ON, OFF and EARTH switching positions;
a pivotable actuator operable to rotate the switching shaft between its switching positions, the pivotable actuator comprising a sleeve, a helical spring surrounding the sleeve, a first retainer secured to the sleeve and engageable with one end of the spring, and a second retainer secured to the switching shaft and engageable with another end of the spring;
a releasable detent arrangement coupled with the switching shaft and with the spring, the arrangement comprising a detent carrier secured to the shaft and carrying a pair of detents, and circumferentially spaced pairs of latching rollers fixedly arranged around the switching shaft to each determine a respective one of said switching positions when engaged by the detents;
a manually operated lever secured to the sleeve to rotate the latter in a direction from OFF to ON and from OFF to EARTH and vice versa, thereby taking with it, via the first retainer, the end of the spring which is in its path, while the other end of the spring is held by the second retainer, and the detents are engaged with the rollers associated with the starting position;
a release device secured to the sleeve for rotation therewith and operable, when the particular spring end engaged by the first retainer has moved through a predetermined angle, to release the detent situated in the relevant direction of rotation from engagement with its roller so that the switching shaft and the detent carrier are then rotated rapidly by the action of the other end of the spring and the second retainer from OFF to ON, from OFF to EARTH and from EARTH to OFF; and
a storage drive sub-assembly comprising a disconnecting spring which has its spring force releasable when a fuse of a fusing arrangement is blown or when an open circuit trip has occurred; wherein,
1. a crank lever is secured to the switching shaft and engages a switch rod of the storage drive sub-assembly, said switch rod carrying a support roller and said disconnecting spring;
2. the circuit breaker spring is attached at one end to an end of the switch rod remote from the crank lever and is attached at its other end to a rocker pivotally mounted on a first pin which engages a first slot formed in the switch rod and a plate;
3. the plate receives a second pin which engages a second slot formed in the switch rod and which forms the axis of rotation for a detent lever which is pivotable with a detent shoulder arranged adjacent to said support roller;
4. the detent lever has a recessed seat for receiving said support roller and carries a cam roller urged under spring force to engage a rocker arm pivotable about a fixed axis;
5. the detent shoulder of the detent lever lies on an arc which is eccentric to the axis of rotation of the detent lever;
6. the free end of said rocker arm is engageable by a support detent and by a release detent to hold the free end and prevent the rocker arm from pivoting, the support detent being moveable out of a blocking position by a connecting link connected to said crank lever, and the release detent being moveable out of the blocking position via a trip rod controlled by a fusing arrangement and/or an open circuit trip;
7. a blocking detent is pivotally mounted on said rocker for movement under spring action below a fixed stop, said blocking detent being moveable against the spring action to engage with a hook of said detent lever, and the end of the blocking detent facing said fixed stop lying on an arc eccentric to the pivot axis of the blocking detent; and
8. the hook of said detent lever lies on an arc eccentric to said second pin.
In preferred embodiments the invention features a three-position electrical switch which incorporates either of the previously described driving mechanisms.
In the utilization of this novel driving mechanism there is the advantage that an operator only has to carry out one switching operation each time. This is very advantageous because it prevents error that can result when an operator must perform different switching operations each time.
Other features and advantages of the invention will be apparent from the following detailed description, and from the claims.
For a full understanding of the present invention, reference should now be made to the following detailed description and to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
An embodiment of the driving mechanism according to the invention, for a three-position electrical switch, will now be described in more detail, by way of example only, with reference to the accompanying drawing, which are described as follows:
FIG. 1 is a perspective view of a jump-drive sub-assembly of the driving mechanism.
FIG. 2 is a side view of a storage drive sub-assembly of the mechanism in the OFF position, with a disconnecting spring under tension.
FIG. 3 is a view similar to FIG. 2, but with the storage drive sub-assembly in the ON position, and the disconnecting spring under tension.
FIG. 4 is a view similar to FIG. 2, but with the storage drive sub-assembly in the OFF position, and disconnecting spring released.
FIG. 5 is a view similar to FIG. 2, but with the storage drive sub-assembly in the EARTH position, and the disconnecting spring under tension.
DETAILED DESCRIPTION
Referring now to the jump-drive sub-assembly shown in FIG. 1, switch shaft 1, is rotatable from a middle OFF position in one direction to an ON position, and in the opposite direction to an OFF position.
When switch shaft 1 is rotated from the OFF position to the left (counter-clockwise), switching to the ON position occurs. When it is rotated in the opposite direction, switching to EARTH occurs. The ON and EARTH positions are interchangeable.
A pivotable actuator for shaft 1 comprises sleeve 2 mounted on switch shaft 1, which has helical bending spring 3 wound coaxially around it.
Bending spring 3 comprises offset leg ends 3a, 3b, which are separated from each other by cam 4 (first retainer) which is arranged between them, and second retainer 5 which is arranged below cam 4.
Cam 4, a tension lever 6 and a rocker arm 7, are united with sleeve 2. Tension lever 6 is the attaching point for a handle (not shown).
Retainer 5, on the other hand, is secured to switch shaft 1 together with detent carrier 8, which carries two detents 9, 10.
Pairs of support rollers 12 and 12a, 13 and 13a, and 14 and 14a are in fixed arrangement in an arc around switch shaft 1. The element carrying support rollers 12-14a is omitted from the drawing for the sake of clarity.
Support rollers 12 and 12a are associated with the OFF position shown in FIG. 1.
Support rollers 13 and 13a define the ON position, while support rollers 14 and 14a are provided for the EARTH position.
Sleeve 2 is rotatable around switch shaft 1, by means of tension lever 6, from OFF in the ON direction and from OFF in the EARTH direction, and vice versa.
The method of operation of the jump drive sub-assembly shown in FIG. 1 is as follows:
When sleeve 2 is rotated from the OFF switch position (shown) to the ON position, bending spring leg 3b, situated in the direction of rotation, is taken up by cam 4 which is secured to sleeve 2, while bending spring leg 3a is retained by retainer 5, and detents 9 and 10 are clamped between support rollers 12 and 12a, as shown.
When helical bending spring 3 has been sufficiently pre-tensioned for switching on, that is, when a predetermined angle of rotation of bending spring leg 3b has been achieved, detent 10, situated in the direction of rotation, is pivoted free of support roller 12a by the rocker arm 7, via a (second) guide rod 16 acting against a spring 10a.
As soon as detent 10 leaves support roller 12a, retainer 5 released with detent 10 and switch shaft 1 connected to retainer 5 is rotated with a jump into the ON switch position in the direction of rotation by bending spring leg 3a, which was previously secured by retainer 5. This releases helical bending spring 3, and detents 9, 10 now extend between support rollers 13 and 13a.
When switching is carried out from OFF to EARTH, bending spring leg 3a is taken up by cam 4 and bending spring leg 3b is retained by retainer 5. Detents 9, 10 extend, as before, between support rollers 12 and 12a.
After bending spring leg 3a has passed through its path of rotation, detent 9, which is situated in the direction of rotation, is pivoted free of support roller 12a by rocker arm 7 via a (first) guide rod 15 which acts against spring leg 9a.
When detent 9 has left support roller 12, the support is removed from retainer 5. Switch shaft 1 is now rotated suddenly into the EARTH position by bending spring leg 3b (retained up till now by retainer 5). In this switch position, detents 9, 10 extend between support rollers 14 and 14a. The spring legs 9a and 10a effect the swinging back of the detents from the pivoted-out position to their respective positions between support roller pairs 12 and 12a, 13 and 13a, and 14 and 14a.
Another crank lever 20 is secured to switch shaft 1 as well as to retainer 5 and detent carrier 8. Crank lever 20, together with switch shaft 1, is pivotable into the switch positions OFF, EARTH, ON, and vice versa. The unbroken outline of crank lever 20 indicates the OFF switch position, while the dash outlines of the crank lever 20 indicates the ON and EARTH switch positions.
Referring now to the storage drive sub-assembly shown in FIGS. 2 to 5, only two elements from FIG. 1 are shown. These are switch shaft 1, shown in section, and crank lever 20. These two parts, 1, 20, are the members of the jump drive sub-assembly shown in FIG. 1 which connect the storage drive sub-assembly, shown in FIGS. 2 to 5, and the jump drive sub-assembly.
In FIG. 2 all the reference numbers are entered, while in FIGS. 3 to 5 only those numbers which are referred to in the description of the method of carrying out the switching operations, are entered.
As shown in FIG. 2, crank lever 20 is connected by a hinge to switch rod 21 at fulcrum 22.
Switch rod 21 carries support roller 23 and disconnecting spring 24. Spring 24 is released when either a fuse is "blown" or an open circuit trip of a shunt trip device has occurred.
One end of disconnecting spring 24 is attached to the upper end of switch rod 21 and the other end is attached to a first pin 26 of rocker 25, which is pivotable about rotation point 25a.
First pin 26 engages firt slot 27 (FIG. 2) of switch rod 21, and longitudinal slot 28a of cover plate 28.
A second pin 29 also engages plate 28 and a second slot 30 of switch rod 21. Pin 29 is also the axis of rotation for detent lever 31.
Detent lever 31 has an arcuate detent shoulder 32. Central point 32a of the arc of detent shoulder 32 lies eccentric to second pin 29.
Detent lever 31 includes, detent shoulder 32, recessed seat 34 for support roller 23, and cam roller 35.
Rocker arm 38, which is pivotable about fixed axis 39, has curved surface 37 which is held against cam roller 35 by spring 36.
Rotation of the free end of arm 38 is blocked by support detent 45 and release detent 46.
Support detent 45 can be moved out of the blocking position by crank lever 20 which acts via connecting link 47, against spring 45a.
Blocking pawl 46, which is held in place by spring 46a, can be moved out of the blocking position by trip rod 48.
The trip rod 48 is operated by an open circuit trip of a shunt trip device or an indicator pin of a fuse (not shown). During operation by an open circuit trip or by an indicator pin of a fuse, the trip rod 48 contacts the blocking pawl 46 and turns it against the force of spring 46a in such a way that the rocker arm 38, and with it the stored spring tension of disconnecting spring 24, is released.
Blocking detent 58, mounted on rocker 25, is pivotable, below fixed stop 57, about pivot pin 56.
Blocking detent 58 is pivotable onto hook 31a of detent lever 31, in response to the force exerted by spring 55.
The upper end of blocking detent 58, which faces fixed stop 57, lies on an arc eccentric to pivot pin 56. The central point of the arc is located at 58a.
The method of operation of the storage drive sub-assembly, shown in FIGS. 2 to 5, will now be described.
Referring to FIG. 2, the storage drive is shown in the OFF position with disconnecting spring 24 under tension.
Crank lever 20 is placed in the middle OFF position.
Support roller 23 rests on shoulder 32 of detent lever 31. Due to the eccentricity between second pin 29 and central point 32a of the arc of shoulder 32, detent lever 31 is pressed along with cam roller 35 against curved surface 37 of rocker arm 38 by disconnecting spring 24.
To prevent pivoting of rocker arm 38, its free end is blocked by support detent 45 and by blocking pawl 46.
Hook 31a of detent lever 31 will now move to a position exactly below the lower end of blocking detent 58.
Referring now to FIG. 3, the storage drive is shown in the ON position, with disconnecting spring 24 under tension.
This position is reached by the previously described operation of the jump drive (see FIG. 1) starting from the OFF position, with disconnecting spring 24 under tension.
Crank lever 20 moves, during switching from OFF to ON, from its middle position to its lower position. This downward motion also pulls both switch rod 21 and support roller 23 downward.
Since support roller 23 is supported on detent shoulder 32, detent lever 31 is drawn downward with it.
Rocker 25 is also pivoted downward due to the motion of second pin 29, cover plate 28 and first pin 26.
Blocking detent 58 is drawn against stop 25b by spring 55.
The downward motion of crank lever 20 causes downward motion of connecting link 47, which pivots support detent 45 against spring 45a, and out of its blocking position. This occurs just before the ON position is reached as a result of an appropriate arrangement of longitudinal slot 47a.
To switch from ON to OFF by means of the jump drive mechanism, switch rod 21 together with support roller 23, are pushed upward by crank lever 20.
Support roller 23 is located at the upper end of longitudinal slot 28a, so that plate 28 is moved upward by upward motion of the roller.
Plate 28 in turn, pulls up detent lever 31, and rocker 25 pivots above first pin 26 and into the OFF position.
Blocking detent 58 is placed against the end of the pivot path of rocker 25 on fixed stop 57, and the lower end of detent 58 engages exactly behind hook 31a.
The upwards movement of crank lever 20 displaces connecting link 47 and permits support detent 45 to pivot under rocker arm 38. This prevents rotation of arm 38 and results in the position shown in FIG. 2.
Referring to FIG. 4, the storage drive is shown in the OFF position, with disconnecting spring 24 released.
To switch from the ON position described above, with disconnecting spring 24 under tension, to the OFF position by means of disconnecting spring 24, trip rod 48 is pushed upward against spring 46a and blocking pawl 46 is pivoted out of its blocking position.
Rocker arm 38 is thereby released and pivoted to the left against the force exerted by spring 36.
Detent lever 31 is support by rocker arm 38 and therefore lever 31 follows arm 38 by rotating around second pin 29 as a result of the pressure of disconnecting spring 24 acting on detent shoulder 32.
The motion of detent lever 31 releases support roller 23, which moves upward as a result of the upward force exerted by disconnecting spring 24 via second pin 29, plate 28 and first pin 26.
At the same time, rocker 25 moves into the OFF position, in which blocking detent 58 abuts fixed stop 57, and the lower end of blocking detent 58 moves against hook 31a of detent lever 31.
In order to re-tension disconnecting spring 24, crank lever 20 must be jumped due to the action of bending spring 3 (FIG. 1). Spring 3 pushes switch rod 21 upward while rocker 25 remains stationary due to blocking detent 58 which is supported on fixed stop 57.
First pin 26, plate 28 and second pin 29 also remain stationary.
Disconnecting spring 24 is suspended by one end on switch rod 21 and by the other end on first pin 26 of rocker 25, so that it is tensioned with an upward movement of switch rod 21, while releasing bending spring 3.
When bending spring 3 is released, detents 9, 10 pivot between support rollers 12 and 12a (FIG. 1).
At the same time that detents 9, 10 pivot between the pair of support rollers 12 and 12a, detent lever 31 is placed below support roller 23 and rocker arm 38 follows cam roller 35, as it pivots due to the force exerted by spring 36.
Support detent 45 and blocking pawl 46 pivot into their blocking positions due to the forces exerted by springs 45a and 46a respectively.
Meanwhile, hook 31a of detent lever 31 rotates free of blocking detent 58, so the position shown in FIG. 2 results.
Referring now to FIG. 5, the storage drive mechanism is shown in the OFF position, with the disconnecting spring relaxed.
Switch shaft 1 moves to the EARTH position as a result of the release of bending spring 3, previously described. Crank lever 20 is rotated out of its middle position and into its upper position, so that switch rod 21 together with support roller 23, are pushed upward.
Support roller 23 lies at the upper end of longitudinal slot 28a.
Plate 28 is also moved upward with switch rod 21.
Plate 28 takes detent lever 31 and rocker 25 upward. Rocker 25 moves upward into it EARTH position by pivoting around first pin 26.
As a result of the pivoting movement of rocker 25, blocking detent 58 moves below fixed stop 57 and is engaged behind hook 31a of detent lever 31.
Cam roller 35 now abuts, as before, curved surface 37 of rocker arm 38, which is prevented from rotating by detent 45.
There has thus been shown and described a novel apparatus for a driving mechanism for a three-position electrical switch which fulfills all the objects and advantages sought. Many changes, modifications, variations and other uses and applications of the subject invention will, however, become apparent to those skilled in the art after considering this specification and the accompanying drawings which disclose embodiments thereof. All such changes, modifications, variations and other uses and applications which do not depart from the spirit and scope of the invention are deemed to be covered by the invention which is limited only by the claims which follow. | A three-position electrical driving mechanism having a jump-drive sub-assembly, a pivotable actuator and associated spring arrangement for storing energy, a detent arrangement and associated latches for holding the detents in place, a release arrangement for disengaging the detents from the latches, and a storage drive sub-assembly which is operable in response to a blown fuse or an open circuit trip. This switch requires the operator to perform the same switching operation each time the switch is utilized, and therefore errors that occur when an operator must perform several different operations are avoided. | 7 |
CROSS REFERENCES TO RELATED APPLICATIONS
Those objects of this invention relating to the reduction of the emissions of oxides of nitrogen, unburned hydrocarbons and carbon monoxide via the engine exhaust gas are achieved by methods basically similar to those used and described in my earlier patent application entitled, "Improved Gasoline Engine Torque Controller," filing date of Aug. 20, 1973, Ser. No. 389715.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The field of this invention is four stroke cycle, spark ignition, gasoline engines, and, more specifically, the valve driving mechanism and torque control means for such engines.
The term "conventional, four stroke cycle, gasoline engine" is used hereinafter and in the claims to mean the known and conventional combinations of cylinders, cylinder heads, pistons operative within said cylinders and connected to a crankshaft via connecting rods, engine oil supply system, cooling system, spark ignition system, flywheels, starting system, fuel supply system, fuel-air mixing system, exhaust pipes, intake pipes fitted with the usual torque controlling throttle plate, intake valve and intake valve drive mechanism, exhaust valve and exhaust valve drive mechanism, etc., as necessary for the proper operation of said conventional, four stroke cycle gasoline engine. The term "conventional intake valve and exhaust valve driving mechanism" is used hereinafter and in the claims to mean the known and conventional combinations of cams driven at half crankshaft speed to actuate valve lifters and push rods which in turn actuate rocker arms acting directly on the engine intake and exhaust valves to open these valves and return springs acting directly on the engine intake and exhaust valves to close these valves, as used commonly on conventional, four stroke cycle, gasoline engines. The term conventional intake valve and exhaust valve driving mechanism is used hereinafter and in the claims to include also the known and conventional combinations of overhead cams driven at half crankshaft speed to actuate valve lifters acting directly on the engine intake and exhaust valves to open these valves and return springs acting directly on the engine intake and exhaust valves to close these valves, as used occassionally on conventional, four stroke cycle, gasoline engines. The term "usual torque controlling throttle plate" is used hereinafter and in the claims to refer to the throttling valve interposed between the fuel-air mixing device and the intake air pipe connecting to the inlet port of the engine intake valve, said throttling valve acting to control engine torque by throttling the air-fuel mixture on its way into the engine cylinder during the intake stroke and thus reduce the pressure and quantity of the mixture in the cylinder, as used commonly to control torque of conventional, four stroke cycle, gasoline engines.
2. Description of the Prior Art
When the speed of a conventional four stroke cycle gasoline engine, equipped with the conventional intake valve and exhaust valve driving mechanism is increased in order to increase the power output of the engine a speed is finally reached beyond which the engine fails to function properly due to the occurrence of "valve float." Engine valves are said to "float" when the force of the valve closing, return springs is inadequate to overcome the inertia of the mass of the valve, rocker arm, push rod and tappet mechanism and in consequence this mechanism does not follow the cam during the closing of the valve. When the engine designer seeks to prevent valve float by increasing the strength and force of the return spring his efforts are partially offset by the necessarily increased mass and inertia of the return spring itself. Higher engine speeds without valve float can indeed be obtained by using overhead cam shafts which allow reducing the mass whose inertia must be overcome by the return spring. But overhead camshafts are expensive and still have a definite upper limit of engine speed beyond which valve float occurs.
The temperature of the exhaust valves of a conventional four stroke cycle gasoline engine increase rapidly as engine speed is increased due to increased net flow rate of hot exhaust gas over the valve. As a result the exhaust valve deteriorates more rapidly and has a shorter useful life at increased engine speeds.
Some of those problems of the automobile engine created by the shortage of fuel on the one hand and the public desire for reduced exhaust emissions on the other hand can be alleviated if the gasoline engine can be modified to operate properly over a very wide range of speeds. In this way an engine of small displacement can be operated at lower speeds with high efficiency, low fuel consumption, and reduced emissions to propel the vehicle at moderate speed and grade conditions. This same small displacement engine can be operated at higher speeds with high power output to propel the vehicle on steep grades or at high speeds or for rapid acceleration. Since the majority of the running of an automobile engine is at moderate speeds on moderate grades at net improvement in both fuel consumption and exhaust emissions can be realized by substituting the above described small displacement, wide speed range gasoline engine for the present large displacement, moderate speed range gasoline engine required to give the same acceleration, top speed and hill climbing capability. To achieve this desireable, small displacement, wide speed range gasoline engine design will require extensive changes to many portions of the engine, the vehicle transmission and the vehicle drive line but this invention concerns only modifications to the intake valve and exhaust valve driving mechanism so that it will operate properly over a very wide range of engine speeds.
The conventional four stroke cycle gasoline engine operates on the approximate equivalent of the Otto cycle and, in consequence, the temperatures at any point in the engine process do not change appreciably when engine torque is reduced by operating the usual torque controlling throttle plate to throttle the intake air-fuel mixture. Throttling acts to reduce the pressure and density of the intake mixture in the cylinder and in this way the quantity of mixture in the cylinder is reduced and hence the torque is reduced. The temperatures of the air-fuel mixture in the cylinder and of the burned gases after combustion are not, however, appreciably changed by throttling. The concentrations of the undesirable oxides of nitrogen formed during combustion decrease as the temperatures in the cycle are decreased, particularly the maximum temperatures in the cycle following completion of combustion. Hence the oxides of nitrogen concentration in the exhaust gas of a conventional four stroke cycle gasoline engine equipped with the usual torque controlling throttle plate do not change appreciably as engine torque is reduced as is shown in references A and B. This is a serious disadvantage of the conventional four stroke cycle gasoline engine in automobile and other applications where most of the engine operation is at reduced torque settings.
The usual torque controlling throttle plate maldistributes the unevaporated liquid portions of gasoline between the several cylinders of a multicylinder gasoline engine. In consequence some cylinders operate too rich in fuel for the amount of air available and increased quantities of unburned hydrocarbon and carbon monoxide are emitted via the exhaust gas of these cylinders.
Emissions of oxides of nitrogen, unburned hydrocarbons and carbon monoxide by gasoline engines are widely recognized as undesireable since they are pollutants themselves and some of them participate actively in the creation of other types of harmful air pollutants. It is the reduction of these harmful exhaust emissions which constitutes an important beneficial object of my invention.
The usual torque controlling throttle plate produces, at reduced torque, an intake manifold pressure necessarily reduced well below the exhaust manifold pressure and the efficiency of the engine is reduced by the loss due to pumping the gas against this difference in manifold pressure.
SUMMARY OF THE INVENTION
It is an object of this invention to provide a valve drive mechanism for four stroke cycle gasoline engines which positively opens the valve at the desired time in the engine cycle and also positively closes the valve at the desired time in the engine cycle at all speeds of the engine. The conventional engine intake valve and exhaust valve driving mechanism uses cams and connecting linkage to open the valve and springs to close the valve and has an upper speed limit for satisfactory running beyond which the spring cannot close the valve quickly enough. By positively opening and closing the engine valves the valve drive mechanism of this invention permits satisfactory running at higher engine speeds than can be used with the conventional valve driving mechanism and this is one of the beneficial objects of this invention.
The oil flow positive valve drive mechanisim of this invention causes a flow of oil to occur over the stems of the engine intake and engine exhaust valves. In this way these engine valves are cooled by the oil and hence operate at a lower temperature which prolongs the useful life of these engine valves and this is another of the beneficial objects of this invention.
The oil flow positive valve drive mechanism of this invention comprises, a positive displacement oil pump element driven by the engine camshaft or crankshaft which positively displaces oil via a valve opening element into the opening end of a piston and cylinder valve actuator to positively open the engine valve at the proper time and also positively displaces oil via a valve closing element into the closing end of the valve actuator to positively close the engine valve at the desired time. This positive displacement oil pump has displacement well in excess of the valve actuator and this excess flow passes out of the actuator when the valve motion has ceased, via spill ports into a reservoir element and from thence into the engine lubricating oil supply system. The valve opening element consists of a pair of valves, operated by the camshaft at camshaft speed, one of these valves, the supply valve, directing oil from positive displacement oil pump element to the opening end of the valve actuator element, the other valve, the relief valve, allowing oil to escape from the opposite, or closing, end of the valve actuator so that the engine valve is positively opened at the proper time in the engine cycle. The valve closing element is similar to the valve opening element except that it directs oil from the pump element into the closing end of the valve actuator and allows oil to escape from the opposite, or opening, end of the valve actuator at that time in the engine cycle when the valve is to be closed. Both the valve opening element and the valve closing element thus consist of at least two portions, that portion rotating with the camshaft which determines the time of opening and closing of the supply valve and the relief valve, and that non-rotating portion to which the necessary connections are made from the positive displacement oil pump element, to and from the valve actuator element and to the engine oil sump.
A further beneficial object of the oil flow positive valve drive mechanisms described herein is to reduce the quantity of undesireable oxides of nitrogen emitted via the engine exhaust gas of a four stroke cycle, spark ignition gasoline engine when operated at reduced torque.
Another beneficial object of this invention is to reduce the quantities of undesireable unburned hydrocarbons and carbon monoxide emitted via the engine exhaust gas of a four stroke cycle, spark ignition, gasoline engine at reduced torque as compared to the quantities of such emissions from conventional four stroke cycle gasoline engines equipped with the usual torque controlling throttle plate.
Those beneficial objects of this invention relating to reducing the quantities of the several kinds of exhaust emissions are achieved by incorporating in the oil flow positive valve drive mechanisms for all the intake valves on a gasoline engine, as an engine torque control means, devices which delay the closing time of the engine intake valve by an adjustable amount but do not change the opening time of the engine intake valve.
Adjustment of intake valve closing time is achieved on the oil flow positive valve drive mechanism of this invention by making the non-rotating portion of the valve closing element for the intake valve moveable about the engine camshaft through the desired torque control angle of closing time variation. The valve closing element is then fitted with connection means from the positive displacement oil pump, to and from the valve actuator and to the engine oil sump which maintain these connections throughout the full adjustment of the non-rotating portion of the valve closing element through the torque control angle.
In the normal operation of a four stroke cycle gasoline engine the intake valve is opened when the piston is at or near top dead center, and about to begin the intake stroke, and this valve is subsequently closed when the piston is next at or near bottom dead center at the end of the intake stroke. As intake valve closing is longer delayed, beyond this latter bottom dead center position of the piston, an increasing portion of the air-fuel mixture, drawn into the engine cylinder during the intake stroke, is pushed back into the intake manifold as the piston rises during the compression stroke. As a result less air fuel mixture remains within the cylinder to be subsequently burned, the longer intake valve closing is delayed and the engine torque is correspondingly reduced. In this way engine torque and power output may be controlled by adjusting the delay of intake valve closing by use of the devices of this invention.
When engine torque is reduced by delay of intake valve closing, as described above, the compression ratio and thus the compression pressure and temperature, are reduced. In consequence, gas temperatures during combustion and expansion are also reduced. The undesireable oxides of nitrogen are formed during or soon after the combustion process and the quantities formed and surviving to be emitted with the exhaust gas decrease as the gas temperatures are reduced. In this way the device of this invention reduce the emission of oxides of nitrogen at reduced torque, the reduction being greater the greater is the reduction of torque by increasing delay of intake valve closure. Present designs of four stroke cycle gasoline engines control torque by throttling the air fuel mixture on its way into the engine cylinder during the intake stroke and thus reduce the pressure of mixture in the cylinder. But the compression ratio and gas temperatures are not reduced by throttling and, in consequence, the emissions of oxides of nitrogen remain high at part load.
Although delayed intake valve closing reduces the engine compression ratio it does not reduce the expansion ratio upon which the engine efficiency primarily depends. Thus, at part load, an engine using the devices of this invention does not operate upon the equivalent of an Otto cycle but operates rather upon the approximate equivalent of an Atkinson cycle.
When engine torque is controlled by delay of intake valve closure with the devices of this invention the pumping work loss described heretofore does not occur since the pressure is essentially the same in both intake and exhaust manifolds. In this way the devices of this invention improve the part load efficiency of a gasoline engine by eliminating the pumping work loss.
When torque is controlled by use of the devices of this invention no throttle plate is used and the aforementioned maldistribution of liquid gasoline and consequent increased exhaust emissions of unburned hydrocarbons and carbon monoxide do not occur. In this way the devices of this invention act to reduce undesireable emissions of unburned hydrocarbons and carbon monoxide at part load.
BRIEF DESCRIPTION OF THE DRAWINGS
The further detailed description of this invention will refer in part to the accompanying drawings which show particular forms of the invention as follows:
FIG. 1 shows in outline an assembly of a portion of an oil flow positive valve drive mechanism installed on a gasoline engine.
FIG. 2 shows in outline one form of positive displacement oil pump element.
FIG. 3 shows in outline one form of valve opening element or exhaust valve closing element.
FIG. 4 shows a developed view of the moving ports portion of the valve opening element shown in FIG. 3 along the developed arc cross section A--A.
FIG. 5 shows a developed view of the non-rotating ports portion of the valve opening element shown in FIG. 3 along the developed arc cross section A--A.
FIG. 6 shows in outline one form of intake valve closing element.
FIG. 7 shows a developed view of the moving ports portion of the intake valve closing element shown in FIG. 6 along the developed arc cross section B--B.
FIG. 8 shows a developed view of the non-rotating ports portion of the intake valve closing element shown in FIG. 6 along the developed arc cross section B--B.
FIG. 9 shows a developed view of the stationary connection unit of the intake valve closing element shown in FIG. 6 along the developed arc cross section B--B.
FIG. 10 shows a cross section view of a typical valve actuator element secured to the engine valve and the engine frame as shown.
FIG. 11 shows a cross section view of a typical oil reservoir element.
REFERENCES CITED
A. "engine Speed and Load Effects on Charge Dilution and Nitric Oxide Emissions," by W. R. Aiman, Society of Automotive Engineers, Paper No. 720256, presented January 1972 SAE meeting.
B. "exhaust Emissions from Small, Utility, Internal Combustion Engines," by Messrs. B. H. Eccleston and R. W. Hurn, Society of Automotive Engineers, Paper No. 720197, presented January 1972 SAE meeting.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A preferred embodiment of the oil flow positive valve drive mechanism of this invention is shown in part in FIG. 1 as installed on a conventional four stroke cycle gasoline engine. Only those portions of the conventional four stroke cycle gasoline engine as relate to this invention are shown in FIG. 1 as follows:
The engine piston, 10, operative within the engine cylinder, 11, is shown connecting to the engine crankshaft, 12, via the engine connecting rod, 13, and at slightly after top dead center at the start of the engine intake stroke with crankshaft rotation as indicated by the arrow, 14. The engine intake valve, 15, is starting to open so that as the piston, 10, descends on the intake stroke fresh air-fuel mixture will be drawn into the engine cylinder, 11, from the engine intake air system, 16, via the fuel-air mixing device, 17. The crankshaft timing gear, 18, drives the camshaft timing gears, 19 and 101, and hence the engine camshafts about their centerlines, 102 and 103, at exactly one half the crankshaft speed. Two engine camshaft centerlines, 102 and 103, and two camshaft timing gears, 19 and 101, are shown in FIG. 1, but this is done only to improve the clarity of FIG. 1, as in common usage a single engine camshaft and camshaft timing gear will suffice. The engine oil supply system manifold, 104, which supplies lubricating oil under pressure to the several bearings and rubbing surfaces within the gasoline engine is also shown in FIG. 1.
The improvement of this invention comprises; removing the usual torque controlling throttle plate, commonly located just beyond the fuel-air mixing device, 17, and in the engine intake air system, 16, and additionally replacing the conventional intake valve and exhaust valve driving mechanisms with oil flow positive valve drive mechanisms. The portion of an oil flow positive valve drive mechanism shown in FIG. 1 comprises the following elements:
a. A positive displacement oil pump element, 105, positively driven by an eccentric, 106, on the engine camshaft, 102.
b. A valve opening element, 107, whose rotating cylindrical passage component, 108, is driven at the speed of the camshaft, 103.
c. A valve actuator element, 109, which is a double acting piston and cylinder actuator whose actuator piston, 110, connects to, or is integral with, the engine intake valve, 15, and whose actuator cylinder, 111, connects to or is integral with the engine cylinder head, 112.
d. An oil reservoir element, 113, from which oil can discharge into the engine oil supply system manifold, 104.
Additionally required to complete the oil flow positive valve drive mechanism, and not shown in FIG. 1, is a valve closing element, whose mechanical functioning is similar to that of the valve opening element, 107, except that it closes the engine intake valve as described in detail hereinafter.
The several elements of the oil flow positive valve drive mechanism connect to the various portions of the conventional four stroke cycle gasoline engine as described above and, further, connect together and function together as follows:
e. The double acting positive displacement oil pump element, 105, draws engine lubricating oil from the engine lubricating oil sump, 114, via the suction pipe, 115, and the pressure actuated suction valves, 116, and discharges oil via the pressure actuated discharge valves, 118, into the connection, 119, to the non rotating pressure supply port, 120, in the non rotating port ring, 121, portion of the valve opening element, 107.
f. The valve opening element, 107, directs the oil, coming from the positive displacement oil pump element, 105, via the connection 123 to the opening end, 124, of the valve actuator element, 109, at the time in the engine cycle when the engine valve is to be opened. This is done by having the camshaft, 103, index the pressure passage, 122, in the rotating cylindrical passage component, 108, with the non rotating pressure supply port, 120, and simultaneously with the non rotating pressure delivery port, 125, which is axially directly in front of the pressure supply port, at that time in the engine cycle when the valve is to start opening. The pressure passage, 122, is of about 90 camshaft degrees in angular extent and hence the aforedescribed indexing with the ports, 120 and 125, is maintained for about 90° camshaft.
Additionally the valve opening element, 107, allows return flow of oil to occur from the closing end, 126, of the valve actuator, 109, to the engine oil sump, 114, via the connections, 127 and 128, so that the engine valve, 15, can open. This is done by having the camshaft, 103, index the relief passage, 129, in the rotating cylindrical passage component, 108, with the non rotating pressure relief port, 130, and simultaneously with the non rotating vent port, 131, which is axially directly in front of the pressure relief port, at that time in the engine cycle when the spill ports, 132, in the valve actuator element, 109, have been covered by the actuator piston, 110. The relief passage, 129, is of about 90 camshaft degrees in angular extent and hence the aforedescribed indexing with the ports, 130 and 131, is maintained for about 90° camshaft.
g. In the valve actuator element, 109, the actuator piston, 110, is forced downward and hence the engine valve, 15, is opened whenever engine lubricating oil is directed under pressure from the positive displacement oil pump element, 105, into the opening end, 124, of the valve actuator element, while concurrently the oil in the closing end, 126, of the valve actuator is allowed to return flow via the connection, 127, to the engine oil sump, 114. When the engine valve, 15, is fully opened the spill ports, 132, in the valve actuator element are uncovered by the actuator piston, 110, and thereafter the oil delivered by the positive displacement oil pump element, 105, to the valve actuator element, 109, flows as a cooling medium past the actuator piston, 110, through the spill ports, 132, and into the oil reservoir element, 113, via the connection, 133.
The valve actuator element, 109, is also fitted with cushion pistons and cylinders to gradually slow down the valve to a stop and the construction and operation of these cushion pistons and cylinders will be described in detail hereinafter.
h. The oil reservoir element, 113, receives the flow of oil from the positive displacement oil pump element, 105, via the valve actuator element, 109, while holding a back pressure on the oil by action of the reservoir piston, 134, and reservoir piston spring, 135. This back pressure, acting through the connection, 133, and the spill ports, 132, of the valve actuator element, 109, holds the actuator piston, 110, and hence the engine valve, 15, fully open once it has been fully opened, and fully closed once it has been fully closed. Hence the engine valve, 15, will not change position except as controlled by the valve opened element, 107, as described heretofore or the valve closing element as will be described hereinafter. The flow of oil into the oil reservoir element, 113, moves the reservoir piston, 134, against the reservoir piston spring, 135, until the piston uncovers the relief port, 136, and thereafter the flow of oil is directed into the engine oil supply system manifold, 104, via the connection, 137.
Not shown in FIG. 1, but essential to proper operation of the oil flow positive valve drive mechanisms of this invention, is the valve closing element. The valve closing element performs the same function as the valve opening element and by the same method except that it directs oil under pressure from the positive displacement oil pump element, 105, via the connection, 138, into the closing end, 126, of the valve actuator element, 109, and concurrently allows return flow of oil to occur from the opening end, 124, of the valve actuator element, 109, to the engine oil sump, 114, so that the engine valve, 15, can close at the proper time in the engine cycle. To achieve all of the beneficial objects of this invention two different kinds of valve closing elements are used, an exhaust valve closing element and an intake valve closing element. The exhaust valve closing element is similar to the valve opening element described heretofore except that it acts to close the engine exhaust valve at the desired time when the engine piston is at or near top dead center at the end of the exhaust stroke. The intake valve closing element is also similar to the valve opening element described heretofore except that it acts to close the engine intake valve at any chosen time between the usual intake valve closing time when the engine piston is at or near bottom dead center at the end of the intake stroke to any desired later closing time during the compression stroke until slightly before the time when the engine ignition spark is fired. This variation of intake valve closing time is used to control the engine torque and is accomplished by adjusting the non-rotating port ring containing the pressure supply port, the pressure delivery port, the pressure relief port and the vent port, angularly about the camshaft centerline, 103, and hence angularly with respect to the rotating cylindrical passage component via a torque control lever secured to the non-rotating port ring. To maintain proper and continuous connections between the non-rotating but adjustable port ring and the appropriate supply and delivery connections from the positive displacement oil pump element, 105, to and from the valve actuator element, 109, and to the engine oil sump, 114, throughout the full adjustment of the non-rotating port ring, a stationary hollow cylindrical connection ring is fit closely around the non-rotating port ring of the intake valve closing element.
Having thus described a preferred form of the oil flow positive valve drive mechanisms of this invention, how it is connected to the various portions of a conventional four stroke cycle gasoline engine and how the several elements are connected together and how they function together, detailed descriptions of each of the several elements, and some of their various useable forms, will now be presented together with further details of their operation.
The positive displacement oil pump element, 105, shown in detail in FIG. 2, is a double acting single cylinder and piston oil pump comprising the usual pump piston, 20, pump cylinder, 21, pressure actuated suction valves, 116, pressure actuated discharge valves, 118, overpressure relief valves, 22, pump piston rod, 23, eccentric strap, 24, and driving eccentric, 106, which latter is a portion of the engine camshaft, 102, whose rotation for FIG. 2 is shown by the arrow, 25. This positive displacement oil pump element is shown in FIG. 2 in the same operating position as in FIG. 1, with the pump piston, 20, moving away from the camshaft, 102, and hence delivering oil under pressure from that end, 26, of the pump cylinder, 21, away from the camshaft, 102, via the pressure actuated discharge valve into the connection, 119, to the valve opening element, and hence also drawing engine lubricating oil from the engine lubricating oil sump via the suction pipe, 115, and the pressure actuated suction valve into that end, 27, of the pump cylinder, 21, toward the camshaft, 102.
In the running of a conventional four stroke cycle gasoline engine it is desireable that the engine intake valve and the engine exhaust valve be opened as quickly as possible in order to minimize pressure drop and consequent engine power loss due to throttling flow past the partially opened engine valve. For this reason it is preferred that the positive displacement oil pump element be sized, connected, and timed as follows:
i. The displacement of the positive displacement oil pump element, defined as the product of the area of the pump piston, 20, and the pump piston stroke length, is made at least 4 times and preferably at least 10 times the displacement of the valve actuator element, defined as the product of the area of the actuator piston, 110, and the engine valve lift. In this way only a portion of the pump piston stroke length and hence only a portion of the time of a full pump piston stroke is used for the opening and for the closing of the engine valve. As a minimum it is essential that the engine valve be fully opened within the first 90 crankshaft degrees, and hence the first 45 camshaft degrees, which follow the commencement of the engine valve opening. In consequence the ratio of the displacement of the positive displacement oil pump element to the displacement of the valve actuator element should have a value of at least 4.
j. The end, 26, of the pump cylinder, 21, away from the camshaft, 102, delivers oil under pressure via the connection, 119, to the valve opening element and the end, 27, of the pump cylinder, 21, toward the camshaft, 102, delivers oil under pressure via the connection, 138, to the valve closing element. The displacement of the positive displacement oil pump element from the end, 26, away from the camshaft is greater than the displacement of the positive displacement oil pump element from the end, 27, toward the camshaft by the amount of pump displacement lost to the pump piston rod, 23. With these connections engine valve opening may be accomplished more quickly than engine valve closing and this is usually preferred since power is lost largely due to occurrence of throttling during valve opening.
k. The eccentric, 106, is positioned angularly on the camshaft, 102, so that the pump piston, 20, passes its maximum velocity point approximately 90° crankshaft before the engine piston reaches its top dead center position. A further requirement for the angular positioning of the eccentric, 106, on the camshaft, 102, is that the pump piston, 20, is moving away from the camshaft when the engine valve is to be opened and is moving toward the camshaft when the engine valve is to be closed. This timing of the pump insures that a reasonably high value of pump piston velocity and hence oil displacement velocity will prevail both when the engine valve is to be opened and also when the engine valve is to be closed, even though the maximum pump piston velocity is not then used for the opening of the valve.
Any of the several different kinds of positive displacement oil pumps, such as gear pumps or duplex cylinder and piston pumps, could be used as the positive displacement oil pump element of this invention, in lieu of the single cylinder and piston, double acting type of positive displacement oil pump element described above. When used on a multicylinder gasoline engine, the oil being discharged under pressure from any one positive displacement oil pump element, of whatever kind, is to be directed to only one valve actuator element at any one time in the engine cycle. This latter requirement insures that a single positive displacement oil pump element is not called upon to actuate two different valve actuator elements at the same time, since in this latter case one of the valve actuators might not function properly. For duplex cylinder and piston pumps and gear pumps with a large number of gear teeth the oil discharges from the pump at a nearly steady flow rate, and thus when pumps of these kinds are used as positive displacement oil pump elements the pump may be positively driven by either the engine camshaft or the engine crankshaft.
A valve opening element, 107, is shown in a cross section normal to the camshaft centerline, 103, in FIG. 3, with a developed arc cross section, A--A, of the interior surface of the non-rotating port ring, 121, shown in FIG. 5, and a developed arc cross section, A--A, of the exterior surface of the rotating cylindrical passage component, 108, shown in FIG. 4, and comprises the following two components:
1. A non-rotating hollow cylindrical port ring, 121, containing four ports; a pressure supply port, 120, connected externally to the postiive displacement oil pump element, 105, via the connection, 119; a pressure delivery port, 125, connected externally to the opening end, 124, of the valve actuator element, 109, via the connection, 123; a pressure relief port, 130 connected externally to the closing end, 126, of the valve actuator element, 109, via the connection, 127; a vent port, 131, connected externally to the engine lubricating oil sump, 114, via the connection, 128;
2. a rotating cylindrical passage component, 108, fitted closely for sealing purposes to the interior of the non-rotating hollow cylindrical port ring, 121, and being integral with or connected directly to the engine camshaft, 103, and hence rotating at chamshaft speed in the direction shown by the arrow, 30, and containing two separate passages; a pressure passage, 122, which indexes with both the pressure supply port, 120, and the pressure delivery ports, 125; and a relief passage, 129, which indexes with both the pressure relief port, 130, and the vent port, 131; these two passages being displaced along the camshaft centerline, 103, relative to each other so that the pressure passage, 122, cannot index with the vent port, 131, and so that the relief passage, 129 cannot index with the pressure supply port, 120; both the pressure passage, 122, and the relief passage, 129, are of an angular extent of about 90° camshaft.
The pressure passage, 122, and the relief passage, 129, are positioned angularly on the rotating cylindrical passage component, 108, relative to the pair of pressure ports, 120 and 125, and the pair of relief ports, 130 and 131, so that the pressure supply port, 120, is first connected via the pressure passage, 122, to the pressure delivery port, 125, at that time in the engine cycle when the valve is to start opening, and so that the pressure relief port, 130, is first connected via the relief passage, 129, to the vent port, 131, at that somewhat later time in the engine cycle when the spill ports, 132, in the valve actuator element, 109, have been covered by the actuator piston, 110. For example, when the pair of pressure ports, 120 and 125, are located at 180° camshaft directly opposite the pair of relief ports, 130 and 131, as shown in FIG. 3, the pressure passage leading edge, 31, will be 180 degrees less the valve actuator spill port covering delay angle behind the leading edge, 32, of the relief passage, 129, in the direction of rotation, 30.
The exhaust valve closing element can be of identical mechanical construction to the aforedescribed valve opening element and is connected to the valve actuator element, the engine lubricating oil sump, and the closing end of the positive displacement oil pump element, which in FIG. 2 is the pump cylinder end toward the camshaft, as described heretofore, so that it acts to close the engine exhaust valve at the desired time in the engine cycle.
The intake valve closing element differs from the above described exhaust valve closing element in that provision is made to adjust the time of intake valve closing in order to control engine torque. This adjustment is made by moving the non-rotating port ring angularly about the camshaft centerline and then providing for maintaining the necessary external connections to the port ring throughout the adjustment angle. The desired range of adjustment of the engine intake valve closing time, hereinafter and in the claims referred to as the torque control angle, is between the conventional intake valve closing time when the engine piston is at or near bottom dead center at the end of the intake stroke to intake valve closing times later than this during the compression stroke up to but not including the time of firing of the engine ignition spark, which latter is commonly some few crankshaft degrees before top dead center of the engine piston on the compression stroke. The torque control angle is herein expressed in camshaft degrees which are thus one half of the corresponding crankshaft degrees.
An intake valve closing element is shown in a cross section normal to the camshaft centerline in FIG. 6, with a developed arc cross section, B--B, of the exterior surface of the rotating cylindrical passage component, 61, shown in FIG. 7, and with a developed arc cross section, B--B, of the interior surface of the non-rotating adjustable port ring, 62, shown in FIG. 8, and with a developed arc cross section, B--B, of the interior surface of the stationary hollow cylindrical connection unit, 63, shown in FIG. 9. The non-rotating adjustable port ring, 62, and the rotating cylindrical passage component, 61, are seen to be identical to the corresponding portions of the valve opening element shown in FIG. 3, except that the relief passage, 64, has a greater angular extent than the relief passage, 129, in order to accommodate the longer duration of valve opening possible, and the non-rotating adjustable port ring, 62, has the torque control lever, 65, secured to it. The relief passage, 64, has an angular extent of 90 camshaft degrees plus the torque control angle. Control of engine torque is accomplished by movement of the torque control lever, 65, and hence of the non-rotating adjustable port ring, 62, either directly or via whatever additional connecting linkage is convenient. Hence engine torque may be controlled by hand movement of the torque control lever, 65 (as for example in both applications), or by foot movement of the torque control lever, 65 (as for example in automobile applications), or by engine governor mechanism movement of the torque control lever, 65 (as for example in electric generating applications), either directly or via whatever additional connecting linkage is convenient, as is well known in the art. The stationary connection unit, 63, is provided to maintain the necessary external connections to the non-rotating adjustable port ring, 62, and is a hollow cylindrical ring fitted closely for sealing purposes to the exterior of the non-rotating adjustable port ring, 62. Individual supply grooves are recessed into the interior cylindrical surface of the stationary connection unit, 63, the angular extent of each of these supply grooves being somewhat greater than the torque control angle. Each such supply groove is positioned along the axial dimension of the connection unit, 63, so as to index with the corresponding port in the non-rotating adjustable port ring, 62, and is of at least the same axial width as these ports, and is connected externally to the desired connection as follows:
1. The pressure supply groove, 66, connects externally to the pressure discharge outlet, 138, from the closing end of the positive displacement oil pump element, 105, and indexes with the pressure supply port, 67, in the non-rotating adjustable port ring, 62.
2. The pressure delivery groove, 68, connects externally to the closing end, 126, of the intake valve actuator element, 109, and indexes with the pressure delivery port, 69, in the non-rotating adjustable port ring, 62.
3. The pressure relief groove, 601, connects externally to the opening end, 124, of the intake valve actuator element, 109, and indexes with the pressure relief port, 602, in the non-rotating adjustable port ring, 62.
4. The vent groove, 603, connects externally to the engine lubricating oil sump, 114, and indexes with the vent port, 604, in the non-rotating adjustable port ring, 62.
When the pressure passage in the rotating cylindrical passage component no longer connects the pressure supply port to the pressure delivery port, in a valve opening element or a valve closing element, the extra oil flow thereafter discharging under pressure from the positive displacement oil pump element has no place to go. In consequence the overpressure relief valves, 22, on the positive displacement oil pump element are opened by the increase of oil discharge pressure and the extra oil flow is thereby throttled back into the engine lubricating oil sump through these overpressure relief valves. But this method of accommodating the extra oil flow requires a high work input into the positive displacement oil pump element and thus reduces engine efficiency. This particular engine efficiency loss can be minimized by extending the relief passage in the rotating cylindrical passage component of the valve opening element and the valve closing element so that it connects the pressure supply port to the vent port in the non-rotating hollow cylindrical port ring at all angular positions of the rotating cylindrical passage component except those angular positions close to and including those when the pressure passage connects the pressure delivery port to the pressure supply port. This extension of the relief passage, 129, in the rotating cylindrical passage component, 108, of the valve opening element, 107, is shown by the dotted line, C, in FIG. 4. Correspondingly this extension of the relief passage, 64, in the rotating cylindrical passage component, 61, of the intake valve closing element shown in FIG. 6 is shown by the dotted line, D, in FIG. 7. Extended relief passages of this description can only be used when one double acting, single cylinder and piston pump type of positive displacement oil pump element is used for each engine intake valve and for each engine exhaust valve.
The mechanical features of the valve opening elements and valve closing elements described above are seen to be those of timed, port indexing valves and it is evident that other types of valves, such as poppett valves, can also be used in lieu of port indexing valves. For example, to use poppett valves, the rotating cylindrical passage component would be replaced in part by a pair of cams, driven directly by or integrally with the engine camshaft. These cams would then open and close a pair of poppett valves which would replace the non-rotating port ring and the passage portions of the rotating cylindrical passage component to accomplish the same opening and closing of the engine valves as is accomplished by use of port indexing valves. One of these poppett valves, the supply valve, when open would direct oil from the positive displacement oil pump element to the appropriate end of the valve actuator element and the other of these poppett valves, the relief valve, when open would direct return flow of oil from the opposite end of the valve actuator element to the engine oil sump. The timed, port indexing valve form of valve opening element and valve closing element, as described heretofore, is considered preferable because easier and less costly to manufacture, but it is not intended to limit this invention to only this one type of valve.
The valve actuator element, 109, shown in detail in FIG. 10, is a double acting piston and cylinder actuator whose actuator piston, 110, connects to, or is integral with, the engine valve, 15, and fits closely for sealing purposes to the interior bore of the closed ends actuator cylinder, 111, which latter is secured to the engine cylinder head, 112. Oil flow connections are made to the valve actuator element, 109, as follows for an intake valve actuator element:
1. the opening end, 124, of the valve actuator connects to the pressure delivery port, 125, of the valve opening element, 107, via the connection, 123, and also to the pressure relief groove, 601, of the valve closing element shown in FIG. 6, via the connection, 151;
2. the closing end, 126, of the valve actuator connects to the pressure delivery groove, 68, of the valve closing element shown in FIG. 6, via the connection, 152, and also to the pressure relief port, 130, of the valve opening element, 107, via the connection, 127;
3. the spill port, 132, located in the center of the complete motion path of the actuator piston, 110, within the actuator cylinder, 111, connects to the oil reservoir element, 113, via the connection, 133.
The corresponding connections for an exhaust valve actuator element are similar except that those made to the valve closing element are made directly to the ports in the non-rotating port ring of the exhaust valve closing element.
It is preferable that the spill port, 132, be only just fully opened when the actuator piston, 110, is stopped either by the closing of the engine valve, 15, or by coming up against the opening cushion piston, 153, when the engine valve is fully open. Hence the axial length of the cylinder wall sealing portion, 154, of the actuator piston, 110, shall be less than the total engine valve lift by the height of the spill port, 132.
To bring the engine valve, 15, slowly to a stop at the fully opened and fully closed position, and thus to prevent hammering and mechanical damage, cushion pistons, 153 and 155, and cylinders, 156 and 157, are fitted into the valve actuator element. The closing cushion cylinder, 157, is a recessed cylindrical cavity in the actuator piston, 110, and indexes with the closing cushion piston, 155, while the engine valve is completing about the last ten percent portion of its total closing distance, which latter is the valve lift. Correspondingly the opening cushion piston, 153, indexes with the opening cushion cylinder, 156. An oil leakage clearance is provided between the cushion piston and its cushion cylinder so that the oil trapped inside the cushion cylinder, when indexing and hence cushioning commences, can leak out and thus allow full closing and full opening of the engine valve, 15. Additionally a small axial clearance of at least 0.020 inches is provided between the end of the closing cushion piston, 155, and the piston face of the closing cushion cylinder, 157, when the engine valve, 15, is fully closed against the valve seat, 158, to insure that such full closure of the engine valve can always take place.
An oil by pass passage, 159, fitted with a check valve, 160, is provided so that oil may freely enter the closing cushion cylinder, 157, whenever oil is supplied under pressure to the opening end, 124, of the valve actuator element via the connection, 123. In this way the opening of the engine valve is not in any way impeded by the cushion piston and cushion cylinder. The check valve thus seats and seals whenever oil seeks to flow out of the cushion cylinder and unseats and opens whenever oil seeks to flow into the cushion cylinder. A similar by pass passage and check valve are also provided between the opening cushion cylinder, 156, and the closing end, 126, of the valve actuator for this same purpose but these are not shown in FIG. 10 to avoid complicating the drawing unnecessarily.
A cross sectional view of an oil reservoir element, 113, is shown in FIG. 11, comprising a reservoir cavity, 162, a reservoir cylinder, 163, a reservoir piston, 134, a reservoir piston spring, 135, a reservoir piston stop, 166, and relief ports, 136. After the flow of oil from the positive displacement oil pump element, 105, has fully opened or closed the engine valve, 15, and hence has caused the valve actuator spill ports, 132, to be uncovered, the further, and excess, flow of oil from the positive displacement oil pump element, 105, flows from the valve actuator spill ports, 132, via the connection, 133, into the reservoir cavity, 162. This excess flow of oil moves the reservoir piston, 134, against the reservoir piston spring, 135, until the relief ports, 136, are uncovered by the reservoir piston, 134. Once the relief ports, 136, are thus uncovered, the excess flow of oil then flows out the relief ports, 136, into the engine oil supply system manifold, 104, via the connection, 137. While the excess flow of oil is thus occurring via the relief ports, 136, the oil pressure in the reservoir cavity, 162, is equal to the force exerted by the reservoir piston springs, 135, divided by the area of the reservoir piston, 134, and can be set to any desired value by a proper selection of these two factors. When the excess flow of oil ceases the reservoir piston spring, 135, forces the reservoir piston, 134, toward the reservoir cavity, 162, until the relief ports, 136, are covered by the reservoir piston, 134. Thereafter the reservoir piston, 134, will move toward the reservoir cavity, 162, only as needed to compensate for oil leakage occuring elsewhere in the oil flow system, until the reservoir piston, 134, comes to rest against the reservoir piston stop, 166. Until the reservoir piston, 134, comes to rest against the reservoir piston stop, 166, the reservoir piston spring, 135, thus acts upon the reservoir piston, 134, to maintain a desired minimum pressure in the reservoir cavity, 162. This minimum pressure can readily be assured by a proper selection of the area of the reservoir piston, 134, and the spring constant and preset compression of the reservoir piston spring, 135, by methods well known in the art. The pressure thus maintained in the reservoir cavity, 162, acts, via the connection, 133, and the valve actuator spill ports, 132, upon the valve actuator piston, 110, to hold the actuator piston, 110, and hence the engine valve, 15, fully open once it has been opened and fully closed once it has been closed. The axial length of the reservoir piston, 134, along its sealing surface with the reservoir cylinder, 163, must be sufficient to hold the relief ports, 136, closed and sealed when the reservoir piston, 134, rests against the reservoir piston stop, 166, to avoid bleeding oil out of the engine oil supply system manifold, 104.
A separate oil reservoir element, 113, may be connected to each individual engine valve, 15, or alternatively, a single oil reservoir element, 113, may be connected to several or all of the engine valves on a multicylinder engine.
For the preferred embodiment of this invention that portion of the engine camshaft devoted to the driving of the engine valves consists of the following components for any one cylinder of a multicylinder gasoline engine:
1. the eccentric, 106, for positively driving the positive displacement oil pump element, 105, which actuates the engine intake valve, 15;
2. the rotating cylindrical passage component, 108, of the valve opening element, 107, which opens the engine intake valve, 15;
3. the rotating cylinder passage component, 61, of the valve closing element which closes the engine intake valve, 15;
4. the eccentric for positively driving the positive displacement oil pump element which actuates the engine exhaust valve;
5. the rotating cylindrical passage component of the valve opening element which opens the engine exhaust valve;
6. the rotating cylindrical passage component of the valve closing element which closes the engine exhaust valve.
This camshaft must be driven positively, as by gears or chains, at exactly one half the rotative speed of the engine crankshaft. The aforelisted six camshaft components are angularly positioned on the camshaft, as described heretofore, so that opening and closing of the engine intake valves and the engine exhaust valves will occur at the proper times relative to the engine piston motion as follows:
a. the engine exhaust valve opens at or somewhat before the time when the engine piston reaches bottom dead center at the end of the expansion stroke;
b. the engine exhaust valve closes at or about the time when the engine piston reaches top dead center at the end of the exhaust stroke;
c. the engine intake valve opens at or about the time when the engine piston reaches top dead center at the end of the exhaust stroke and start of the intake stroke;
d. for maximum engine torque, that is at full throttle, the engine intake valve closes at or about the conventional time when the engine piston reaches bottom dead center at the end of the intake stroke and start of the compression stroke;
e. for reduced engine torque, that is at part throttle, the engine intake valve closes at times, adjustable by adjustment of the non-rotating adjustable port ring, 62, of the engine intake valve closing element, between the conventional intake valve closing time, described above for maximum engine torque, to intake valve closing times later than this during the compression stroke up to, but not including, the time of firing of the engine ignition spark, the later the engine intake valve closing time the less the engine torque.
If alternate positive displacement oil pump elements, such as gear pumps, or alternate types of valve opening elements and valve closing elements, such as cam actuated poppett valves, are used in lieu of the aforedescribed preferred embodiment of this invention the portion of the engine camshaft devoted to the driving of the engine valves must be changed to include only the camshaft rotated portions of the alternate elements. | This invention provides a valve drive mechanism which positively opens and closes the valves of a gasoline engine at all speeds and provides a flow of cooling oil to the valves. Additionally this mechanism permits control of engine torque by delay of the closing of the engine intake valve and thus reduces the emmissions of oxides of nitrogen. This valve drive mechanism consists of oil pumps driving the valve open and closed via selector valves connecting to a hydraulic valve actuator. | 5 |
FIELD
This disclosure relates to workpiece cooling, and more particularly to an apparatus and a method of cooling a textured workpiece.
BACKGROUND
An electronic device may be created from a workpieces that has undergone various processes. One of these processes may include introducing impurities or dopants to alter the electrical properties of the original workpiece. For example, charged ions, as impurities or dopants, may be introduced to a workpiece, such as a silicon wafer, to alter electrical properties of the workpiece. One process that introduces impurities to the workpiece may be an ion implantation process.
An ion implanter is used to perform ion implantation or other modifications of a workpiece. A block diagram of a conventional ion implanter is shown in FIG. 1 . Of course, many different ion implanters may be used. The conventional ion implanter may comprise an ion source 102 that may be biased by a power supply 101 . The system may be controlled by controller 120 . The operator communicates with the controller 120 via user interface system 122 . The ion source 102 is typically contained in a vacuum chamber known as a source housing (not shown). The ion implanter system 100 may also comprise a series of beam-line components through which ions 10 pass. The series of beam-line components may include, for example, extraction electrodes 104 , a 90° magnet analyzer 106 , a first deceleration (D 1 ) stage 108 , a 70° magnet collimator 110 , and a second deceleration (D 2 ) stage 112 . Much like a series of optical lenses that manipulate a light beam, the beam-line components can manipulate and focus the ion beam 10 before steering it towards a workpiece or wafer 114 , which is disposed on a workpiece support 116 .
In operation, a workpiece handling robot (not shown) disposes the workpiece 114 on the workpiece support 116 that can be moved in one or more dimensions (e.g., translate, rotate, and tilt) by an apparatus, sometimes referred to as a “roplat” (not shown). Meanwhile, ions are generated in the ion source 102 and extracted by the extraction electrodes 104 . The extracted ions 10 travel in a beam-like state along the beam-line components and implanted on the workpiece 114 . After implanting ions is completed, the workpiece handling robot may remove the workpiece 114 from the workpiece support 116 and from the ion implanter 100 .
Referring to FIGS. 2A and 2B , there is shown a block diagram illustrating the workpiece support 116 supporting the workpiece 114 during the ion implantation process. As illustrated in FIG. 2A , the workpiece support 116 may comprise a top layer 210 that is in contact with the workpiece 114 . In addition, the workpiece support 116 may also include at least one cooling region 206 . During the implantation process, cooling gas may be provided to the cooling region 206 prevent the workpiece 114 from overheating. The workpiece support 116 may have gas channels and conduits to allow this cooling gas to flow to the cooling region 206 . The workpiece support 116 may further include a plurality of lift pins 208 that may move so as to push the workpiece 114 away from the workpiece support 116 in the direction indicated by the arrows. The lift pins 208 may be retracted within the workpiece support 116 , as illustrated in FIG. 2B .
The workpiece support 116 may be cylindrical in shape, such that its top surface is circular, so as to hold a disc-shaped workpiece. Of course, other shapes, such as squares, are possible. To effectively hold the workpiece 114 in place, most workpiece supports typically use electrostatic force. By creating a strong electrostatic force on the upper side of the workpiece support 116 , the support can serve as the electrostatic clamp or chuck, the workpiece 114 can be held in place without any mechanical fastening devices. This minimizes contamination, avoids wafer damage from mechanical clamping and also improves cycle time, since the workpiece does not need to be unfastened after it has been implanted. These clamps typically use one of two types of force to hold the substrate in place: coulombic or Johnsen-Rahbek force.
As seen in FIG. 2A , the workpiece support 116 traditionally consists of several layers. The first, or top, layer 210 , which contacts the workpiece 114 , is made of an electrically insulating or semiconducting material, such as alumina, since it must produce the electrostatic field without creating a short circuit. In some embodiments, this top layer 210 is about 4 mils thick. For those embodiments using coulombic force, the resistivity of the top layer 210 , which is typically formed using crystalline and amorphous dielectric materials, is typically greater than 10 14 Ω-cm. For those embodiments utilizing Johnsen-Rahbek force, the volume resistivity of the top layer 210 , which is formed from a semiconducting material, is typically in the range of 10 10 to 10 12 Ω-cm. The term “non-conductive” is used to describe materials in either of these ranges, and suitable for creating either type of force. The coulombic force can be generated by an alternating voltage (AC) or by a constant voltage (DC) supply.
Directly below this layer is a conductive layer 212 , which contains the electrodes that create the electrostatic field. This conductive layer 212 is made using electrically conductive materials, such as silver. Patterns are created in this layer, much like are done in a printed circuit board to create the desired electrode shapes and sizes. Below this conductive layer 212 is a second insulating layer 214 , which is used to separate the conductive layer 212 from the lower portion 220 .
The lower portion 220 is preferably made from metal or metal alloy with high thermal conductivity to maintain the overall temperature of the workpiece support 116 within an acceptable range. In many applications, aluminum is used for this lower portion 220 .
Initially, the lift pins 208 are in a lowered position. The workpiece handling robot 250 then moves a workpiece 114 to a position above the workpiece support 116 . The lift pins 208 may then be actuated to an elevated position (as shown in FIG. 2A ) and may receive the workpiece 114 from the workpiece handling robot 250 . Thereafter, the workpiece handling robot 250 moves away from the workpiece support 116 and the lift pins 208 may recede into the workpiece support 116 such that the top layer 210 may be in contact with the workpiece 114 , as shown in FIG. 2B . The implantation process may then be performed with the lift pins 208 in this recessed position. After the implantation process, the workpiece 114 is unclamped from the workpiece support 116 , having been held in place by electrostatic force. The lift pins 208 may then be extended into the elevated position, thereby elevating the workpiece 114 and separating the workpiece 114 from the top layer 210 of the workpiece support 116 , as shown in FIG. 2A . The workpiece handling robot 250 may then be disposed under the workpiece 114 , where it can retrieve the implanted workpiece 114 at the elevated position. The lift pins 208 may then be lowered, and the robot 250 may then be actuated so as to remove the workpiece 114 from the implanter.
This technique is effective, especially when the workpiece 114 and the workpiece support 116 are both substantially planar. This allows the workpiece 114 and workpiece support 116 to couple together closely when clamped. This tight coupling serves to confine the cooling gas to the cooling regions 206 .
However, in some embodiments, the workpiece may not be planar. For example, it is advantageous for the surface of a solar cell to be textured, to minimize reflection of photons and thus maximize cell efficiency. One common method to achieve this textured surface is to bathe the workpiece in acid or alkaline solutions. While such baths are less expensive than other processes, they will texture both sides, not just the surface exposed to the photons. However, since manufacturing costs are critical for the solar cell industry, this may be an accepted consequence. Also ion implantation into the rear surface of the cell is beneficial in producing a back surface field, so even were only the front of the cell textured it would still be necessary to clamp the textured surface for this application.
One consequence of textured workpiece surfaces is that the workpiece support 116 and the workpiece 114 no longer form a tight coupling as described earlier. FIG. 3 shows an exaggerated view of the interface between a textured workpiece 200 and a workpiece support 116 . This interface presents several issues related to the cooling of the workpiece 200 . First, the textured surface of workpiece 200 implies that a lower percentage of the surface of the workpiece 200 is in physical contact with the workpiece support 116 . This reduces the ability of the workpiece support 116 to pull heat away from the workpiece 200 via conduction. A second issue is related to the cooling gas. The workpiece 116 may have cooling conduits 210 , as shown in FIG. 3 . Gas is injected into the area between the workpiece 200 and the workpiece support 116 , as described above, through the cooling conduits 210 . However, since there is less contact between the textured workpiece 200 and the workpiece support 116 , the gas is not confined to cooling regions (as described in connection to FIG. 2A ). As result, the gas escapes from the edges between the textured workpiece 200 and the workpiece support 116 . This increases the pressure within the chamber, which is preferably held as close to vacuum as possible, and decreases the pressure between workpiece and clamp. This is detrimental to the ion implantation process, and is detrimental in cooling the workpiece 200 . A third issue is the lower available electrostatic clamp force due to the higher average gap.
Accordingly, there is a need in the art for an improved workpiece support that can effectively cool textured workpieces.
SUMMARY
The problems of the prior art are overcome by the apparatus and method of this disclosure. A layer is added on top of a workpiece support. This layer is sufficiently soft so as to conform to the textured workpiece. Furthermore, the layer has a dielectric constant such that it does not alter the normal operation of the underlying electrostatic clamp. In some embodiments, the locations of the ground and lift pins are moved to further reduce the leakage of backside gas.
BRIEF DESCRIPTION OF THE DRAWINGS
In order to facilitate a fuller understanding of the present disclosure, reference is now made to the accompanying drawings, in which like elements are referenced with like numerals. These drawings should not be construed as limiting the present disclosure, but are intended to be exemplary only.
FIG. 1 represents a traditional ion implantation system;
FIG. 2A represents a block diagram showing a workpiece support supporting a workpiece with the lift pins extended;
FIG. 2B represents a block diagram showing a workpiece support supporting a workpiece with the lift pins recessed;
FIG. 3 represents an exaggerated view of the interface between a textured workpiece and a workpiece support in the prior art;
FIG. 4 represents an exaggerated view of the interface between a textured workpiece and a workpiece support according to one embodiment; and
FIG. 5 is a top view of a workpiece support according to one embodiment.
DETAILED DESCRIPTION
In the present disclosure, several embodiments of an apparatus and a method for cooling a textured workpiece are introduced. For purpose of clarity and simplicity, the present disclosure will focus on an apparatus and a method for cooling a textured workpiece that is processed by a beam-line ion implanter. Those skilled in the art, however, may recognize that the present disclosure is equally applicable to other types of processing systems including, for example, a plasma immersion ion implantation (“PIII”) system, a plasma doping (“PLAD”) system, other implantation systems, an etching system, an optical based processing system, and a chemical vapor deposition (CVD) system. As such, the present disclosure is not to be limited in scope by the specific embodiments described herein.
As described above in FIG. 3 , a tight coupling may not be possible when a textured workpiece 200 is placed atop a conventional workpiece support 116 . FIG. 4 shows a first embodiment, where a layer 220 is applied to the top surface of the workpiece support 116 . The layer 220 is sufficiently soft so as to conform to the shape of the textured workpiece 200 . Typically hardness is measured by durometer, and a Shore D scale of about 40 to 90 is appropriate. In addition, it is desirable that the dielectric constant of the layer is relatively low, but much greater than air. The dielectric constant of air is approximately 1 and the dielectric constant of typical electrostatic clamp hard dielectrics is 5 to 10. Desirable dielectric constants for the compliant dielectric are in the range of 2 to 5. Furthermore, the breakdown voltage of the material should be fairly high, so as to function properly when the electrostatic fields are applied. High quality SiO 2 has a breakdown voltage of 10E6 volts/cm, and the breakdown voltage of the dielectric is typically above 5E6/cm.
Materials satisfying these requirements are referred to as “compliant dielectrics”, and include materials such as silicone rubber, polymers such as polyurethane, fluorocarbons like Teflon and certain epoxies.
The layer of compliant dielectric does not need to be thick to perform its intended function. In fact, the thickness of layer 220 can be between 10 μm and 50 μm. This layer 220 can be applied in several ways. For example, many compliant dielectrics are available as thin sheets and can be applied by bonding to the platen surface using some amount of heat. In another embodiment, the compliant dielectric is deposited on the workpiece support. In this embodiment, the dielectric is deposited from a vapor with a subsequent phase change, but without a chemical change from the precursor). In other embodiments, chemical vapor deposition (CVD) from a mixture of precursor gasses (with a chemical change as the film deposits onto the surface) is performed. In other embodiments, physical deposition, such as sputtering from a target made of the dielectric, is performed. For each of these deposition approaches, the apertures for lift and ground pins, and any gas distribution holes are typically masked to prevent deposition in these regions.
The ability of the layer 220 to conform to the shape of the textured workpiece 200 allows a tighter coupling between the textured workpiece 200 and the workpiece support 116 . As stated above, this will improve heat transfer from the workpiece 200 to the workpiece support 116 . Furthermore, this tighter coupling provides closed cooling regions 230 into which the gas can be injected via conduits 210 between the workpiece 200 and the workpiece support 116 (also known as backside gas). Because the layer 220 conforms to the shape of the textured workpiece 200 , the backside gas does not escape from the edges between these components and remains within the closed cooling regions 230 .
In some embodiments, the locations of the gas conduits 210 , relative to the lift pins and ground pins are also altered. Because the textured workpiece 200 may allow gas to escape from the edges, the gas conduits 210 are moved closer to the middle of the workpiece support. FIG. 5 shows a top view of a workpiece support 300 , with gas conduits 210 located near the center of the support 300 . This creates a gas distribution region 240 that is distanced from the edge of the workpiece support 300 . Located outside of the gas distribution region 240 are the ground and lifting pins 260 .
Note that in some embodiments, the compliant dielectric creates an adequate seal such that the gas distribution region 240 can be larger and include a greater portion of the workpiece. In further embodiments, the gas conduits 210 are located outside of the lifting and ground pins 260 .
The present disclosure is not to be limited in scope by the specific embodiments described herein. Indeed, other various embodiments of and modifications to the present disclosure, in addition to those described herein, will be apparent to those of ordinary skill in the art from the foregoing description and accompanying drawings. Thus, such other embodiments and modifications are intended to fall within the scope of the present disclosure. Further, although the present disclosure has been described herein in the context of a particular implementation in a particular environment for a particular purpose, those of ordinary skill in the art will recognize that its usefulness is not limited thereto and that the present disclosure may be beneficially implemented in any number of environments for any number of purposes. | A workpiece support, which more effectively cools a textured workpiece is disclosed. A layer is added on top of a workpiece support. This layer is sufficiently soft so as to conform to the textured workpiece. Furthermore, the layer has a dielectric constant such that it does not alter the normal operation of the underlying electrostatic clamp. In some embodiments, the locations of the ground and lift pins are moved to further reduce the leakage of backside gas. | 7 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present application is a continuation of co-pending U.S. patent application Ser. No. 12/243,374, filed on Oct. 1, 2008, which is a continuation of U.S. patent application Ser. No. 11/938,883, filed on Nov. 13, 2007, which is a continuation of U.S. patent application Ser. No. 11/510,791, and now U.S. Pat. No. 7,297,072, which is a divisional of No. 10/799,118, and now U.S. Pat. No. 7,214,142, which is a continuation-in-part of U.S. patent application Ser. No. 10/428,061, and now U.S. Pat. No. 7,029,403, which is a continuation-in-part of U.S. patent application Ser. No. 09/551,771, and now U.S. Pat. No. 6,605,007. The disclosures of the parent patent applications are incorporated herein in their entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to an improved golf club head. More particularly, the present invention relates to a golf club head with an improved striking face and improved shock absorption between the mating portions making up the body of the club head.
BACKGROUND
[0003] The complexities of golf club design are well known. The specifications for each component of the club (i.e., the club head, shaft, hosel, grip, and sub-components thereof) directly impact the performance of the club. Thus, by varying the design specifications, a golf club can be tailored to have specific performance characteristics.
[0004] The design of club heads has long been studied. Among the more prominent considerations in club head design are loft, lie, face angle, horizontal face bulge, vertical face roll, face progression, face size, sole curvature, center of gravity, material selection, and overall head weight. While this basic set of criteria is generally the focus of golf club engineering, several other design aspects must also be addressed. The interior design of the club head may be tailored to achieve particular characteristics, such as the inclusion of hosel or shaft attachment means, perimeter weights on the face or body of the club head, and fillers within hollow club heads.
[0005] Golf club heads must also be strong to withstand the repeated impacts that occur during collisions between the golf club and the golf ball. The loading that occurs during this transient event can accelerate the golf ball to several orders of magnitude greater than gravity. Thus, the club face and body should be designed to resist permanent deformation or catastrophic failure by material yield or fracture. Conventional hollow metal wood drivers made from titanium typically have a uniform face thickness exceeding 0.10 inch to ensure structural integrity of the club head.
[0006] Players generally seek a metal wood driver and golf ball combination that delivers maximum distance and landing accuracy. The distance a ball travels after impact may be dictated by variables including: the magnitude and direction of the ball's translational velocity; and, the ball's rotational velocity or spin. Environmental conditions, including atmospheric pressure, humidity, temperature, and wind speed, further influence the ball's flight. However, these environmental effects are beyond the control of the golf equipment manufacturer. Golf ball landing accuracy is driven by a number of factors as well. Some of these factors are attributed to club head design, such as center of gravity and club face flexibility.
[0007] The United States Golf Association (USGA), the governing body for the rules of golf in the United States, has specifications for the performance of golf balls. These performance specifications dictate the size and weight of a conforming golf ball. One USGA rule limits the golf ball's initial velocity after a prescribed impact to 250 feet per second ±2% (or 255 feet per second maximum initial velocity). To achieve greater golf ball travel distance, ball velocity after impact and the coefficient of restitution of the ball-club impact must be maximized while remaining within this rule.
[0008] Generally, golf ball travel distance is a function of the total kinetic energy imparted to the ball during impact with the club head, neglecting environmental effects. During impact, kinetic energy is transferred from the club and stored as elastic strain energy in the club head and as viscoelastic strain energy in the ball. After impact, the stored energy in the ball and in the club is transformed back into kinetic energy in the form of translational and rotational velocity of the ball, as well as the club. Since the collision is not perfectly elastic, a portion of energy is dissipated in club head vibration and in viscoelastic relaxation of the ball. Viscoelastic relaxation is a material property of the polymeric materials used in all manufactured golf balls.
[0009] Viscoelastic relaxation of the ball is a parasitic energy source, which is dependent upon the rate of deformation. To minimize this effect, the rate of deformation must be reduced. This may be accomplished by allowing more club face deformation during impact. Since metallic deformation may be purely elastic, the strain energy stored in the club face is returned to the ball after impact thereby increasing the ball's outbound velocity after impact.
[0010] A variety of techniques may be utilized to vary the allowable deformation of the club face, including uniform face thinning, thinned faces with ribbed stiffeners and varying thickness, among others. These designs should have sufficient structural integrity to withstand repeated impacts without permanent deformation of the club face. In general, conventional club heads also exhibit wide variations in the coefficient of restitution depending on the impact location on the face of the club. Furthermore, the accuracy of conventional clubs is highly dependent on impact location.
[0011] It has been reported in F. Werner and R. Greig, “How Golf Clubs Really Works and How to Optimize Their Designs”, Ch. 4, pp. 17-21 (2000) that a typical distribution of golf ball hits on the face of a driver club follows an elliptical pattern with its major axis orientating in a direction from high toe to low heel. The size of the hit distribution depends on the handicap of the golfer. Players with low handicap have smaller elliptical distribution and players with high handicap have larger elliptical distribution. These authors also patented golf clubs that have an elliptical outer hitting face that aligns in the direction of high toe to low heel. See U.S. Pat. No. 5,366,233, entitled “Golf Club Face for Drivers,” issued on Nov. 22, 1994. However, there is no teaching to align the coefficient of restitution of the golf club head to the ball impact pattern.
SUMMARY OF THE INVENTION
[0012] The present invention relates to a golf club head adapted for attachment to a shaft. The head includes a hitting face and a body. The hitting face is configured and dimensioned so that it includes at least an inner zone and a concentric intermediate zone. The inner zone has relatively high flexural stiffness and the intermediate zone has lower flexural stiffness. Preferably, the inner zone has a shape that comprises a major axis and a minor axis and the major axis aligns substantially in the direction of high heel to low toe. The inner zone can have an elliptical shape or a substantially parallelogram shape. The inner zone and intermediate zone may have same shape or different shape.
[0013] This arrangement of inner and intermediate zones forms an area of relatively high flexural stiffness in the direction of high heel to low toe, thereby creating high resilience in the direction of high toe to low heel. In other words, this arrangement creates a gradient of flexural stiffness in the direction of high toe to low heel, and produces a desirable effect of manipulating resilience or higher coefficient of restitution (COR) in that direction. This area of improved coefficient of restitution advantageously coincides with the ball impact pattern that golfers typically make on the hitting face.
[0014] The inventive club head encompasses a measurement zone that exhibits high COR where the lowest COR is at least 93% of the peak COR within this measurement zone. The measurement zone is defined by a rectangle having the dimensions of 0.5 inch by 1.0 inch, and the COR values are measured at the corners of the rectangle, the mid-points of the sides and the geometric center of the rectangle. The geometric center of the measurement zone preferably coincides with the geometric center of the face of the club.
[0015] The above is accomplished by providing the inner zone with a first flexural stiffness and the intermediate zone with a second flexural stiffness. Flexural stiffness is defined as Young's modulus or elastic modulus (E) times the zone's thickness (t) cubed or Et 3 . The first flexural stiffness is substantially higher than the second flexural stiffness. As a result, upon ball impact, the intermediate zone exhibits substantial elastic deformation to propel the ball.
[0016] In one embodiment, the first flexural stiffness is at least three times the second flexural stiffness. In other embodiments, the first flexural stiffness is six to twelve times the second flexural stiffness. More preferably, the first flexural stiffness is greater than 25,000 lb-in. Most preferably, the first flexural stiffness is greater than 55,000 lb-in. Preferably, the second flexural stiffness is less than 16,000 lb-in. More preferably, the second flexural stiffness is less than 10,000 lb-in.
[0017] Since the flexural stiffness is a function of material properties and thickness, the following techniques can be used to achieve the substantial difference between the first and second flexural stiffness: 1) different materials can be used for each portion, 2) different thicknesses can be used for each portion, or 3) different materials and thicknesses can be used for each portion.
[0018] The golf club head may further include a perimeter zone disposed between the intermediate zone and the body of the club. In one embodiment, the perimeter zone has a third flexural stiffness that is at least two times greater than the second is flexural stiffness
[0019] In the club heads discussed above, the inner, intermediate and optional perimeter zones can have any shape that has a major axis and a minor axis, such as elliptical, rhombus, diamond, other quadrilateral shapes with one or more rounded corners and the like. The zones may also have a substantially parallelogram shape. Furthermore, the club head inner cavities can have a volume greater than about 100 cubic centimeters, and more preferably a volume greater than about 300 cubic centimeters. In other words, the club head in accordance to the present invention can be used in driver clubs and/or fairway clubs. In addition, the inner, intermediate, and perimeter zones can each have variable thickness.
[0020] Another feature of the present invention is locating the center of gravity of the club head with respect to a Cartesian coordinate system. The origin of the Cartesian coordinate system preferably coincides with the geometric center of the hitting face. The X-axis is a horizontal axis positioned tangent to the geometric center of the hitting face with the positive direction toward the heel of the club. The Y-axis is another horizontal axis orthogonal to the X-axis with the positive direction toward the rear of the club. The Z-axis is a vertical axis orthogonal to both the X-axis and Y-axis with the positive direction toward the crown of the club. The center of gravity is preferably located behind and lower than the geometric center of the face.
[0021] In one preferred embodiment, the center of gravity is spaced from the geometric center along the Z-axis by about −0.050 inch to about −0.150 inch, and more preferably by about −0.110 inch. The center of gravity is preferably spaced about ±0.050 inch, and more preferably about +0.015 inch from the geometric center along the X-axis. The center of gravity is preferably spaced about +2.0 inches and more preferably about +1.35 inches from the geometric center along the Y-axis.
[0022] The hitting face may comprise a face insert and a face support. The face support defines a cavity adapted to receive the face insert. The hitting face may further comprise at least one side wall, which can be a partial crown portion or a partial sole portion. Preferably, the inner zone is located on the face insert, and the intermediate zone may partially be located on the face insert and partially on the face support.
[0023] Another aspect of the invention provides for a crown portion to be composed of a material having a lower density than a body portion. The material for the crown portion selected from such materials as composite, thermoplastic or magnesium, and preferably graphite composite. The crown portion having an inner surface layer integrally composed of a vibration dampening or acoustical attenuating material. One embodiment would include a titanium mesh material.
[0024] An embodiment of the invention includes a non-integral dampening material, juxtaposed between the body and crown portions.
[0025] A preferred embodiment would be a gasket juxtaposed between the body and the crown portions
[0026] Yet still another embodiment of the invention is comprised of a body and light weight crown with a vibration dampening gap there between. The gap is preferably filled with putty or other shock absorption material such as a rubber based structural adhesive.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] Preferred features of the present invention are disclosed in the accompanying drawings, wherein similar reference characters denote similar elements throughout the several views, and wherein:
[0028] FIG. 1 is a toe side, front, perspective view of an embodiment of a golf club head of the present invention;
[0029] FIG. 2 is a heel side, rear, perspective view of the golf club head of FIG. 1 ;
[0030] FIG. 3 is a front, elevational view of the golf club head of FIG. 1 ;
[0031] FIG. 3A is a cross-sectional view of the face of the golf club head of FIG. 1 along line 3 A- 3 A;
[0032] FIG. 3B shows a cross-sectional view the face of the golf club head of FIG. 1 along line 3 B- 3 B;
[0033] FIGS. 3C and 3D are alternative embodiments of FIGS. 3A and 3B , respectively;
[0034] FIG. 4 is a top view of the golf club head of FIG. 1 ;
[0035] FIG. 5 is a bottom, perspective view of the golf club head of FIG. 1 ;
[0036] FIG. 6 is a schematic view of substantially parallelogram shaped the inner and intermediate zones;
[0037] FIG. 7 is a schematic view of the inner and intermediate zones with substantially parallelogram and elliptical shape;
[0038] FIG. 8 is a front, exploded view of another embodiment of the present invention;
[0039] FIG. 9 is a front, exploded view of another embodiment of the present invention;
[0040] FIGS. 10( a )- 10 ( c ) illustrate the results from a comparative example, which compares iso-COR contour lines of conventional golf club head and of an embodiment of the present invention;
[0041] FIG. 11 is a top view of an embodiment of the invention wherein the crown is composed of a composite material;
[0042] FIG. 12 a is a cross-section view of the crown portion attached to the lip section of the outer portion;
[0043] FIG. 12 b is a plan view showing the layer of titanium mesh material integral with the inner surface of the crown portion;
[0044] FIG. 12 c is a cross-section view of another embodiment of the crown portion wherein a titanium mesh ring is integral about the perimeter edge of the crown portion;
[0045] FIG. 12 d is a plan view showing a ring of titanium mesh about the perimeter edge of the crown portion;
[0046] FIG. 12 e is a cross-section view of an embodiment of the invention wherein a gasket is disposed between the lip section of the outer portion and the crown portion;
[0047] FIG. 12 f is a plan view of the gasket of FIG. 12 e;
[0048] FIG. 12 g is a cross-section view of an embodiment of the invention having a gap filled with a shock absorption material between the crown portion and lip section;
[0049] FIG. 12 h is a cross-section view of an embodiment of the invention having an “L” shaped gasket composed of a shock absorption material between the crown portion and lip section;
[0050] FIG. 12 i is a cross-section view of an embodiment of the invention having a “Y” joint on the crown portion;
[0051] FIG. 12 j is a plan view of the inner side of the crown portion showing the plurality of “Y” joints about the perimeter;
[0052] FIG. 13 is a schematic of the front face of an embodiment of the invention depicting the location of the center of gravity;
[0053] FIG. 14 a is a front schematic depicting a 9 point spin variance across the front face of an embodiment of the invention; and
[0054] FIG. 14 b is a front schematic depicting a 9 point spin variance across the front face of a prior art club head.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0055] Referring to FIGS. 1-5 , a first embodiment of a golf club head 10 of the present invention is shown. Club head 10 includes shell 12 with body 14 , hitting face 16 , toe portion 18 , heel portion 20 , sole plate 22 , hosel 24 , bottom portion 26 , crown portion 28 , and rear portion 29 . The sole plate 22 fits in a recess 30 (as shown in FIG. 5 ) in the bottom portion 26 of body 14 . The shell 12 and sole plate 22 create an inner cavity 31 (as shown in FIG. 5 ). The hitting face 16 has an exterior surface 32 and an interior surface 34 . The exterior surface 32 is generally smooth except for external grooves (which are omitted for clarity). Preferably, interior surface 34 has elevated or depressed areas to accommodate the varying thickness of hitting face, as discussed below and shown in FIGS. 3A-3D .
[0056] A golf club shaft (not shown) is attached at hosel 24 and is disposed along a shaft axis SHA. The hosel may extend to the bottom of the club head or may terminate at a location between the top and bottom portions of the head. The hosel can also terminate flush with the top portion or extend into the cavity within the head.
[0057] Inner cavity 31 of club head 10 may be empty, or alternatively may be filled with foam or other low specific gravity material. It is preferred that the inner cavity 31 has a volume greater than 100 cubic centimeters, and more preferably greater than 300 cubic centimeters. In other words, the club head design in accordance to the present invention can be used with any driver club, as well as any fairway club. Preferably, the mass of the inventive club head is greater than 150 grams but less than 250 grams.
[0058] Referring to FIGS. 1 and 3 - 3 D, the face 16 includes an inner zone or portion 36 , an intermediate zone or surrounding portion 38 adjacent the inner zone 36 , and an optional perimeter zone or outer portion 40 . The intermediate zone 38 preferably surrounds inner zone 36 , and the perimeter zone 40 preferably surrounds the intermediate zone 38 . The inner zone 36 is a contiguous zone located on the hitting face 16 and contains a geometric center (“GC”) of the hitting face. As shown, inner zone 36 and its concentric zones have a generally elliptical shape with a major axis in the direction of high heel to low toe. As used herein, the term “ellipse” or “elliptical” refers to non-circular shapes that have discernable major axis and minor axis, and include, but are not limited to, any quadrilateral shapes, geometrical ellipses, quadrilateral shapes with one or more rounded corner(s) and unsymmetrical elliptical shapes. Also, the term “concentric” refers to shapes that substantially encircle or surround other shapes. The “major axis” is defined as the axis coinciding with the longest length that can be drawn through the non-circular shapes without intersecting the perimeter of the shapes at more than two locations, i.e., at the start and end points of said length. The “minor axis” is orthogonal to the major axis at or near its midpoint.
[0059] The major axis of inner portion 36 forms an angle, θ, with the shaft axis, SHA. Preferably, angle θ is between about 10° to about 60°, more preferably between about 20° and about 50°, and most preferably between about 25° and about 45°. Additionally, the ratio of the length of the major axis to the length of minor axis is preferably greater than 1.0 and more preferably less than about 6.0.
[0060] Preferably, zones 36 , 38 and 40 are concentric to each other within hitting face 16 . The inner zone 36 has a first thickness T 1 . The intermediate zone 38 has a second thickness T 2 . The first thickness T 1 is greater than the second thickness T 2 . Typically, when the club head is cast, the perimeter zone 40 is thicker than the intermediate zone 38 . Alternatively, the hitting face may also be forged. However, the present invention is not limited to any manufacturing technique. T 1 may range from about 1.5 mm to about 7.5 mm and T 2 may range from about 0.8 mm to about 3.0 mm. Preferably, the first thickness T 1 is equal to about one and a half (1.5) times the thickness T 2 to about four (4) times the thickness T 2 .
[0061] The thickness relationships between the zones 36 , 38 , and 40 are provided so that a predetermined relationship exists between flexural stiffness exhibited by each of the zones.
[0062] For clubs that have a hitting face made from a single material, such as titanium or titanium alloy, the area of highest thickness corresponds to the portion with the highest flexural stiffness. Flexural stiffness (FS) of each portion is defined as:
[0000] FS=E ( t 3 ),
[0000] where:
[0063] E is the elastic modulus or Young's modulus of the material of the portion, and
[0064] t is the thickness of the portion.
[0000] Young's modulus of titanium is about 16.5×10 6 lbs/in 2 , and thickness is typically measured in inch. Hence, FS as used in this application has the unit of lb-in.
[0065] The inner zone 36 has a first flexural stiffness FS 1 . The intermediate zone 38 has a second flexural stiffness FS 2 . The perimeter zone 40 has a third flexural stiffness FS 3 . The predetermined relationship between the portions is that the first flexural stiffness FS 1 is substantially greater than the second flexural stiffness FS 2 , and the optional third flexural stiffness FS 3 is substantially greater than the second flexural stiffness FS 2 . Preferably, the first flexural stiffness FS 1 is at least three times greater than the second flexural stiffness FS 2 , i.e., (FS 1 /FS 2 )≧3. When the above ratio of flexural stiffness is less than three, the inner zone sustains excessive deformation during impact and accuracy of the club is diminished. More preferably, the first flexural stiffness FS 1 is about six (6) to twelve (12) times greater than the second flexural stiffness FS 2 . Most preferably, the first flexural stiffness FS 1 is about eight (8) times greater than the second flexural stiffness FS 2 . Preferably, the third flexural stiffness FS 3 is at least two times greater than the second flexural stiffness FS 2 , i.e., (FS 3 /FS 2 )≧2.
[0066] Alternatively, the flexural stiffness, FS 1 , FS 2 or FS 3 , can be determined for two combined adjacent zones, so long as the preferred ratio (FS 1 /FS 2 )≧3 or (FS 3 /FS 2 )≧2 is satisfied. For example, FS 1 , can be calculated to include both zones 36 and 38 , and FS 3 can be calculated to include both zones 38 and 40 .
[0067] The thickness of the zones, T 1 and T 2 , may be constant within the zone as illustrated in FIGS. 3A and 3B , or may vary within the zone as illustrated in FIGS. 3C and 3D . For the purpose of determining FS, when the thickness varies, a weighted average thickness is calculated. The determination of FS when the thickness varies or when the material is anisotropic is fully discussed in the parent patent application, which has already been incorporated by reference in its entirety.
[0068] In club head 10 (as shown in FIGS. 3-3D ), the above flexural stiffness relationships are achieved by selecting a certain material with a particular elastic modulus and varying the thickness of the zones. In another embodiment, the flexural stiffness relationships can be achieved by varying the materials of the zones with respect to one another so that the zones have different elastic moduli and the thickness is changed accordingly. Thus, the thickness of the zones can be the same or different depending on the elastic modulus of the material of each zone. It is also possible to obtain the required flexural stiffness ratio through the use of structural ribs, reinforcing plates, and thickness parameters.
[0069] Quantitatively, it is preferred that the first flexural stiffness FS 1 is greater than 25,000 lb-in. When the first flexural stiffness is less than 25,000 lb-in excessive deformation of the inner region can occur during impact and accuracy is diminished. More preferably, the first flexural stiffness FS, is greater than 55,000 lb-in. Preferably, the second flexural stiffness FS 2 is less than 16,000 lb-in. When the second flexural stiffness is greater than 16,000 lb-in, the resultant ball velocity is reduced. More preferably, the second flexural stiffness FS 2 is less than 10,000 lb-in and, most preferably, less than 7,000 lb-in.
[0070] Referring to FIG. 3 , it is preferred that inner zone 36 has an area that is between about 15% and about 60% of the exterior surface area 32 . The percentage of face area is computed by dividing the area of each zone 36 , 38 , or 40 by the total face area of exterior surface 32 . It should be noted that the face area of exterior surface 32 is equivalent to the total area of zones 36 , 38 , and 40 . When the inner zone 36 is less than 15% of the total face area, then accuracy can be diminished. When inner portion 36 is greater than 60% of the face area 32 , then the coefficient of restitution can be diminished.
[0071] Referring again to FIG. 1 , the club head 10 is further formed so that a center of gravity of the club head has a predetermined relationship with respect to a Cartesian coordinate system with its center located on hitting face 16 and coincident with the geometric center GC of the face 16 . The hitting face 16 includes a vertical centerline VCL and a horizontal centerline HCL perpendicular thereto. The geometric center (GC) of hitting face 16 is located at the intersection of centerlines VCL and HCL. The VCL and HCL are co-linear with the X-axis and the Z-axis of a Cartesian coordinate system, described below. Preferably, the GC of the inner zone 36 is spaced from the GC of hitting face 16 by a distance of less than about 0.10 inch, more preferably less than about 0.05 inch and most preferably less than about 0.025 inch. The GC of inner zone 36 may be coincident with the GC of hitting face 16 . The GC of inner zone 36 can be defined as the intersection between the major axis and the minor axis of the zone.
[0072] The Cartesian coordinate system is defined as having the origin coincident with the geometric center of the hitting face. The hitting face is not a rectilinear plane, but due to the bulge and roll radii it is a curvilinear surface. The X-axis is a horizontal axis lying tangent to the geometric center of the hitting face with the positive direction toward the heel of the club. The Y-axis is another horizontal axis orthogonal to the X-axis with the positive direction toward the rear of the club. The Z-axis is a vertical axis orthogonal to both the X-axis and Y-axis with the positive direction toward the crown of the club.
[0073] The center of gravity is preferably located both behind and lower than the geometric center of the face, when the club head is resting on a flat surface (i.e., at its natural loft). In one preferred embodiment, the center of gravity of club head 10 is spaced from the geometric center along the Z-axis between about −0.050 inch and about −0.150 inch, more preferably about −0.110 inch. The center of gravity is preferably spaced about ±0.050 inch, more preferably about 0.015 inch, from the geometric center along the X-axis. The center of gravity is preferably spaced about 2.0 inches or less and more preferably about 1.35 inches or less from the geometric center along the Y-axis.
[0074] The center of gravity for the club head can be achieved by controlling the configuration and dimensions of the club head in addition to adding predetermined weights to the sole plate or to the club head. Other known methods of weight manipulation can be used to achieve the inventive center of gravity location as set forth above.
[0075] FIG. 6 illustrates another embodiment of the present invention. Central zone 36 has a generally parallelogram shape, such that the opposite sides are generally parallel and the angles formed between adjacent sides are rounded. More specifically, the acute angle α of central zone 36 is preferably between 40° and 85°. Additionally, the major axis of central zone 36 , as shown, forms an angle β with the HCL, which preferably is between 5° and 45°. The major axis is the line connecting the two acute angles of the parallelogram. Similar to the embodiments disclosed is above, intermediate zone 38 surrounds central zone 36 , and the relative thickness and ratio of FS between zone 36 and zone 38 follow the relationships discussed above.
[0076] As shown in FIG. 7 , central zone 36 can be an ellipse while intermediate zone 38 can have a generally parallelogram shape. Conversely, central zone 36 can have a generally parallelogram shape, while intermediate zone 38 can be an ellipse. Furthermore, as illustrated intermediate zone 38 may have varying width.
[0077] In accordance to another aspect of the present invention, hitting face 16 may comprise a face insert 42 and face support 44 , as shown in FIG. 8 . In this embodiment, hitting face 16 is delineated from crown 28 , toe 18 , sole 22 and heel 20 by parting line 46 . Central zone 36 is preferably disposed on the back side of face insert 42 , and, as shown, has a generally parallelogram shape. Intermediate zone 38 , designated as 38 1 and 38 2 , can be disposed partially on face insert 42 and partially on face support 44 . A transition zone 37 having variable thickness is disposed between central zone 36 and intermediate zone 38 . Preferably, the thickness of central zone 36 is reduced to the lesser thickness of intermediate zone 38 within transition zone 37 . This reduces any local stress-strain caused by impacts with golf balls due to abrupt changes in thickness. Face support 44 defines hole 48 , which is bordered by rim 50 . Face insert 42 can be attached to face support 44 by welding at or around rim 50 . For the purpose of determining the FS ratio for this embodiment, the FS 1 of the inner zone includes both zone 36 and zone 37 .
[0078] In accordance to another aspect of the invention, the face insert may include one or more side walls, wherein the side walls may form part of the crown and/or part of the sole. As shown in FIG. 9 , face insert 52 comprises central zone 36 , transition zone 37 , a portion of intermediate zone 38 , partial crown portion 54 and partial sole portion 56 . Club head 10 correspondingly defines cavity 58 sized and dimensioned to receive face insert 52 . Face insert 52 is preferably welded to club head 10 . Face insert 52 together with face support 60 forms hitting face 16 . Similar to the embodiment illustrated in FIG. 8 , intermediate zone 38 , designated as 38 1 and 38 2 , can be disposed partially on face insert 52 and partially on face support 60 .
Example
[0079] In this example, hitting face 16 has the following construction. The central zone 36 has a substantially parallelogram shape, as shown in FIG. 10( a ), with a major axis measuring about 3 inches and a minor axis about 0.75 inches with a thickness T 1 , of about 0.120 inch. The central zone 36 has a concentric transition zone 37 with a similar shape as the central zone 36 . The intermediate zone 38 surrounds the central and transition zones with a thickness T 2 of 0.080 inch and comprises the remainder of the face hitting area. There is no perimeter zone 40 included in this example. The major axis of zone 36 substantially coincides with the major axis of zone 38 , and these two major axes form angle theta (θ) of about 50° with the shaft axis. Furthermore, zones 36 and 37 comprise about 18% of the total face surface area. A single homogeneous material, preferably a titanium alloy, with a Young's modulus (E) of approximately 16.5×106 lbs/in 2 is used. In this example, the (FS 1 /FS 2 ) ratio is 3.4 when FS 1 includes both zones 36 and 37 and FS 2 includes zone 38 .
[0080] The test results were generated using computational techniques, which include finite element analysis models. In the computer model, the following assumptions were made: club head loft of 9°; club head mass of 195 grams; and club head material is 6AL-4V titanium alloy. The golf ball used in the model was a two-piece solid ball. Finite element models were used to predict ball launch conditions and a trajectory model was used to predict distance and landing area. The impact condition used for club coefficient of restitution (COR) tests was consistent with the USGA Rules for Golf, specifically, Rule 4-1e Appendix II Revision 2 dated Feb. 8, 1999.
[0081] Distributions of coefficient of restitution (COR) are shown in FIGS. 10( b ) and 10 ( c ). The lines indicate contour lines, similar to the contour lines in topography maps or weather maps, and indicate lines of constant COR (hereinafter iso-COR lines). The innermost contour line indicates the highest COR region on the hitting face and outer contour lines indicate lower COR regions on the hitting face. FIG. 10( b ) represents the iso-COR contours for a conventional club having a hitting face with uniform thickness, and FIG. 10( c ) represents the iso-COR contours of the inventive club described in this Example.
[0082] COR or coefficient of restitution is one way of measuring ball resiliency. COR is the ratio of the velocity of separation to the velocity of approach. In this model, therefore, COR was determined using the following formula:
[0000] (v club-post −v bail-post )/(v ball-pre −v club-pre )
[0000] where,
v club-post represents the velocity of the club after impact; v bail-post represents the velocity of the ball after impact; v club-pre represents the velocity of the club before impact (a value of zero for USGA COR conditions); and v ball-post represents the velocity of the ball before impact.
[0087] COR, in general, depends on the shape and material properties of the colliding bodies. A perfectly elastic impact has a COR of one (1.0), indicating that no energy is lost, while a perfectly inelastic or perfectly plastic impact has a COR of zero (0.0), indicating that the colliding bodies did not separate after impact resulting in a maximum loss of energy. Consequently, high COR values are indicative of greater ball velocity and distance.
[0088] The iso-COR contour lines generated by the computational analysis are shown within a rectangle having dimensions of 0.5 inch by 1.0 inch, as typically used in the art. Within this rectangle, the inventive club head exhibits relatively high and substantially uniform COR values. The COR values are measured at nine points within this rectangle, i.e., the corners of the rectangle, mid-points of the sides and the geometric center of the rectangle. Additionally, the geometric center of this rectangular measurement zone preferably coincides with the geometric center of the hitting face of the club. In this example, the lowest COR within this measurement zone is 0.828 and the peak COR is 0.865. According to the present invention, the lowest COR is within 93% of the peak COR. This advantageously produces a hitting face with a substantially uniform COR and large “sweet spot.”
[0089] The iso-COR contour lines of the conventional club shown in FIG. 10( b ) follow a substantially elliptical pattern. Furthermore, the center of the innermost iso-COR contour line, which has the highest COR value, is offset from the geometric center of the rectangular measurement zone, indicating a reduction in COR. The major axis of these contour lines is substantially horizontal.
[0090] The iso-COR contour lines for the inventive club also follow an elliptical pattern, and as shown in FIG. 10 ( c ), the major axis of the pattern does not coincide with the horizontal center line, HCL, of the hitting face. The test results indicate that the major axis of the iso-COR pattern makes an angle, delta (δ), with the HCL. The angle δ is at least 5°, and more preferably at least 7° in the direction from high toe to low heel. While the major axis of central zone 36 with the highest FS runs substantially from high heel to low toe, the major axis of the iso-COR contours runs substantially in a different direction, i.e., from high toe to low heel, which advantageously coincides with the typical hit distribution that golfers make on the hitting face, discussed above. Furthermore, the center of the innermost iso-COR contour line is closer to the geometrical center of the rectangular measurement zone, indicating a higher peak COR value.
[0091] Without being limited to any particular theory, the inventors of the present invention observe that when an elliptical area of high thickness or high FS is present at or near the center of the hitting face with areas of less thickness or lower FS surrounding it, the iso-COR contour lines generally form an elliptical shape where the major axis of the iso-COR contours forms an angle with the major axis of the areas of high thickness or high FS. This arrangement of inner and intermediate zones forms a zone of relatively high flexural stiffness in the direction of high heel to low toe thereby creating high resilience in the direction of high toe to low heel. In other words, this arrangement creates a gradient of flexural stiffness in the direction of high toe to low heel and produces a desirable effect of manipulating resilience or higher coefficient of restitution (COR) in that direction. This area of improved coefficient of restitution advantageously coincides with the ball impact pattern that golfers typically make on the hitting face.
[0092] As shown is FIG. 11 , a club head embodiment of the invention is depicted having a club head 10 , which includes a body portion 60 , a composite crown portion 61 , and a hosel 24 for attaching to a shaft (not shown). The body portion 60 comprises an outer portion 40 that includes a lip section 63 , as shown in FIGS. 12 a, c, e, g, h , and i . The transverse surfaces of the lip section 63 define a cutout 65 . As shown in FIG. 12 a , the crown portion 61 attaches to the first body portion 60 by an outer ledge section 62 being attached to the lip section 63 . The outer ledge section 62 substantially forms a perimeter edge of the crown portion 61 . An inventive aspect of the present invention is the inclusion of a shock absorption layer 66 integral with the inner surface 64 of the crown portion 61 . For an embodiment shown in FIG. 12 a , the shock absorption layer 66 covers substantially the entire inner surface 64 of the crown portion 61 , as depicted by FIG. 12 b . This shock absorption layer 66 is preferably composed of titanium mesh material. Although the crown portion is shown herein as only encompassing the crown of the club head 10 , it is appreciated that it could also include parts of the skirt or hosel sections of the club head 10 . The crown portion 61 may be cast, formed, injection molded, machined or pre-preg sheet formed.
[0093] The density range for crown portion 61 is from about 0.1 g/cc to 4.0 g/cc. Preferably the crown portion 61 may be formed from materials such as magnesium, graphite composite, a thermoplastic, but the preferred material for the crown portion 61 is graphite composite. Preferably, the crown portion 61 has a thickness in the range of about 0.1 mm to about 1.5 mm, and more preferably less than about 1.0 mm.
[0094] An embodiment of the invention is shown in FIGS. 12 c and 12 d . In this embodiment, the titanium mesh layer 66 is integral with the inner surface 64 of the crown portion 61 is in the shape of a ring, such that it is juxtaposed the outer ledge 62 and the lip section 63 .
[0095] Another embodiment of the invention is described on FIGS. 12 e and 12 f , wherein, the shock absorption material is a separate gasket 67 , and is disposed between the outer ledge section 62 and the lip section 63 . Other materials, such as a viscoelastic material or an aluminum foil, may be substituted in lieu of the titanium gasket.
[0096] Another way to dampen vibrations according to the invention is shown in FIG. 12 g , wherein a gap 68 is created between the transverse surfaces of the body portion 60 and the crown portion 61 . In FIG. 12 g , this gap 68 has a substantially rectangular shape, while in FIG. 12 h , an L-shaped gap 69 , creates the bond between the transverse surfaces. However, both are preferably filled with a shock absorbing material such as putty or a rubber based structural adhesive, such as those provided by PPG Industries, Inc. under the trade name CORABOND® HC7707.
[0097] The materials for forming the body portion 60 may be stainless steel, pure titanium or a titanium alloy. The more preferred material comprises titanium alloys, such as titanium 6-4 alloy, which comprises 6% aluminum and 4% vanadium. The body portion 60 may be manufactured through casting with a face insert, or formed portions with a face insert. The face insert is made by casting, machining sheet metal or forming sheet metal. Another embodiment can be created by forming a wrapped face, from forging, stamping, powdered metal forming, or metal-injection molding.
[0098] Tests were conducted on each of two golf clubs of the present invention. The only physical difference between the two clubs was that one of the clubs was manufactured with the shock absorption layer 66 , as shown in FIGS. 12 a and 12 b , and the other club was made without any such shock absorption layer. Identical shaft specifications were used for both test clubs, and the ball was a Pinnacle Gold, as manufactured by Titleist®. Test data taken over a frequency range of 3,000 to 12,000 Hz indicated swing speed is a variable in the percentage of dampening that was achieved. At a swing speed of 90 mph, the noise was dampened between a range of about 28% to 50% over a frequency range of about 3800 Hz to 10,000 Hz, while at a swing speed of 105 mph the noise was dampened about 20% to 32% over the same Hz range.
[0099] An embodiment of the invention provides an improvement in the percentage of club area relative to the head volume. With the composite crown portion 61 being considerably lighter than titanium, weight is removed from the crown and may then be redistributed into weight inserts in the body and face. The weight relocation helps to position the center of gravity lower. As seen in FIG. 13 , an embodiment of the present invention provides a club head with the center of gravity located between 50 to 55% of the face height with a face area greater than 50 cm 2 . The combination of shaft characteristics with the present invention provides for dynamic results. The shaft used in the embodiment is a lightweight rayon Model SL-45, as manufactured by Mitsubishi. It has a weight that is less than 50 grams and preferably less than 48 grams. The shaft torque is greater than about 3.5° and preferably greater than about 4°. The shaft tip stiffness is less than 900 cpm and greater than 600 cpm as measured 320 mm from the tip. The face is closed at an angle greater than 1°, preferably 2°, and the face has an effective hitting area greater than 7.0 in 2 and preferably greater than 7.25 in 2 . Combining this center of gravity location with the ultra-light shaft design and low tip stiffness, a high right to left trajectory is promoted with increased swing speed. The lower center of gravity promotes a high launch, a larger head size yields a higher moment of inertia, and the larger face area allows for more forgiveness.
[0100] As suggested above, FIG. 13 shows the position of the center of gravity as it relates to face height for the King Cobra 454 COMP driver as manufactured by The Acushnet Company and depicts a face area of 48.4 cm 2 , overall club weight of 290 (with a Mitsubishi Rayon SL-45 shaft having a weight of 45 grams, and a length of 45.5″). The magnitude of the effective hitting area of the King Cobra 454 COMP golf club is shown in FIGS. 14 a and 14 b . The effective hitting area of the King Cobra 454 is about 7.5 in 2 versus an effective hitting area of about 5.0 in 2 for an ERC Fusion golf club, as manufactured by the Callaway Golf Company of Carlsbad, Calif.
[0101] A significant performance criteria in the design of a golf club is the club's “forgiveness” or its ability to provide near optimum hitting for golf hits that are not struck right on the perfect “sweet spot” of the club. The “sweet spot” of a golf club is usually referred to as that spot on the club face wherein maximum Coefficient of Restitution is obtained. The golf club of the present invention provides a “sweet zone” or nine (9) points across the club face, in which the club will deliver near maximum COR, at not just one particular point on the club face, but at any point within the sweet zone.
[0102] FIGS. 14 a and 14 b make a 9 point comparison of the club faces of a model 454 Cobra versus the ERC Fusion club of Callaway Golf Company. The spin of the golf ball coming off the club face is an important parameter and in a perfect situation, the spin would be the same for the entire club face. In the design of a club face, having a minimum variance of spin across a large area of the face is a highly desired performance characteristic. The performance data shown on FIGS. 14 a and 14 b are based on striking the golf ball at an 11° launch angle and a club speed of 90 mph. The spin imparted to the ball coming off the King Cobra 454 face is much higher across the entire face (average spin of 2375 rpm) than that of the ERC Fusion club (average spin of 2070 rpm), the variance across the “sweet zone” of the King Cobra 454 club is only 475 rpm to 850 rpm for the ERC Fusion club. This demonstrates a club face that will consistently yield shots more consistent over a greater surface area.
[0103] While various descriptions of the present invention are described above, it should be understood that the various features of each embodiment can be used alone or in any combination thereof. Therefore, this invention is not to be limited to only the specifically preferred embodiments depicted herein. Further, it should be understood that variations and modifications within the spirit and scope of the invention may occur to those skilled in the art to which the invention pertains. For example, the face and/or individual zones can have thickness variations in a step-wise or continuous fashion. Other modifications include a perimeter zone that has a thickness that is greater than or less than the adjacent, intermediate zone. In addition, the shapes of the central, intermediate, and perimeter zones are not limited to those disclosed herein. Accordingly, all expedient modifications readily attainable by one versed in the art from the disclosure set forth herein that are within the scope and spirit of the present invention are to be included as further embodiments of the present invention. The scope of the present invention is accordingly defined as set forth in the appended claims. | A metal wood golf club head adapted for attachment to a shaft, comprising of a body portion and a crown portion, each portion constructed of a different density material. Combining a high-density material in the body portion, with a low-density material in the crown portion, creates an ultra-low center of gravity relative to the geometric face center, resulting in higher launch angles and spin rate ratios. The material for the crown portion is preferably a composite. A vibration dampening gasket is disposed between the ledge and lip sections of the body and crown respectively. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of co-pending U.S. patent application Ser. No. 11/101,305, filed Apr. 7, 2005, which is incorporated herein by reference.
BACKGROUND OF THE DISCLOSURE
[0002] 1. Field of the Invention
[0003] Embodiments of the invention generally relate to a baffle plate used to improve film deposition uniformity in a deposition processing chamber.
[0004] 2. Description of the Background Art
[0005] Liquid crystal displays or flat panels are commonly used for active matrix displays such as computer and television monitors. Plasma enhanced chemical vapor deposition (PECVD) is generally employed to deposit thin films on a substrate such as a transparent substrate for flat panel display or semiconductor wafer. PECVD is generally accomplished by introducing a precursor gas or gas mixture into a vacuum chamber that contains a substrate. The precursor gas or gas mixture is typically directed downwardly through a distribution plate situated near the top of the chamber. The precursor gas or gas mixture in the chamber is energized (e.g., excited) into a plasma by applying radio frequency (RF) power to the chamber from one or more RF sources coupled to the chamber. The excited gas or gas mixture reacts to form a layer of material on a surface of the substrate that is positioned on a temperature controlled substrate support. Volatile by-products produced during the reaction are pumped from the chamber through an exhaust system.
[0006] Flat panels processed by PECVD techniques are typically large, often exceeding 370 mm×470 mm. Large area substrates approaching and exceeding 4 square meters are envisioned in the near future. Gas distribution plates (or gas diffuser plates) utilized to provide uniform process gas flow over flat panels are relatively large in size, particularly as compared to gas distribution plates utilized for 200 mm and 300 mm semiconductor wafer processing.
[0007] FIG. 1 illustrates a cross-sectional schematic view of a thin film transistor structure. A common low temperature polysilicon TFT structure is the top gate TFT structure shown in FIG. 1 . The substrate 101 may comprise a material that is essentially optically transparent in the visible spectrum, such as, for example, glass or clear plastic. The substrate may be of varying shapes or dimensions. Typically, for TFT applications, the substrate is a glass substrate with a surface area greater than about 500 mm 2 . The substrate may have an underlayer 102 thereon. The underlayer 102 may be an insulating material, such as, for example, silicon dioxide (SiO 2 ) or silicon nitride (SiN). An n-type doped silicon layer 104 n is deposited on the underlayer 102 . Alternatively, the silicon layer may be a p-type doped layer. In one embodiment, the n-type doped silicon layer 104 n is an amorphous silicon, which is melted and re-crystallized rapidly by an annealing process to form a polysilicon layer.
[0008] After the n-type doped silicon layer 104 n is formed, selected portions thereof are ion implanted to form p-type doped regions 104 p adjacent to n-type doped regions 104 n . The interfaces between n-type regions 104 n and p-type regions 104 p are semiconductor junctions that support the ability of the thin film transistor to act as a switching device. By ion doping portions of semiconductor layer 104 , one or more semiconductor junctions are formed, with an intrinsic electrical potential present across each junction.
[0009] A gate dielectric layer 108 is deposited on the n-type doped regions 104 n and the p-type doped regions 104 p . The gate dielectric layer 108 may comprise, for example, silicon dioxide (SiO 2 ), silicon nitride (SiN), or silicon oxynitride (SiON), deposited using an embodiment of a PECVD system in accordance with this invention. In one embodiment, the gate dielectric layer 103 is a silicon dioxide (SiO 2 ) layer, deposited using TEOS (tetraethylorthosilicate) and oxygen. TEOS is a liquid source precursor and can be vaporized to be carried into the process chamber. TEOS oxide film is known to have better comformality than silane oxide in the semiconductor industry.
[0010] A gate metal layer 110 is deposited on the gate dielectric layer 108 . The gate metal layer 110 comprises an electrically conductive layer that controls the movement of charge carriers within the thin film transistor. The gate metal layer 110 may comprise a metal such as, for example, aluminum (Al), tungsten (W), chromium (Cr), tantalum (Ta), or combinations thereof, among others. The gate metal layer 110 may be formed using conventional deposition techniques. After deposition, the gate metal layer 110 is patterned to define gates using conventional lithography and etching techniques. After the gate metal layer 110 is formed, an interlayer dielectric 112 is formed thereon. The interlayer dielectric 112 may comprise, for example, an oxide such as silicon dioxide. Interlayer dielectric 112 may be formed using conventional deposition processes. The interlayer dielectric 112 is patterned to expose the n-type doped regions 104 n . The patterned regions of the interlayer dielectric 112 are filled with a conductive material to form contacts 120 . The contacts 120 may comprise a metal such as, for example, aluminum (Al), tungsten (W), molybdenum (Mo), chromium (Cr), tantalum (Ta), indium tin oxide (ITO), zinc oxide (ZnO) and combinations thereof, among others. The contacts 120 may be formed using conventional deposition techniques.
[0011] Thereafter, a passivation layer 122 may be formed thereon in order to protect and encapsulate a completed thin film transistor 125 . The passivation layer 122 is generally an insulator and may comprise, for example, silicon oxide or silicon nitride. The passivation layer 122 may be formed using conventional deposition techniques. While FIG. 1 as well as the supporting discussion provide an embodiment in which the doped silicon layer 104 is an n-type silicon layer with p-type dopant ions implanted therein, one skilled in the art will recognize that forming this and other configurations are within the scope of the invention described below. For example, one may deposit a p-type silicon layer and implant n-type dopant ions in regions thereof. The TFT structure described here is merely used as an example.
[0012] FIG. 2A is a schematic cross-sectional view of one embodiment of a prior art plasma enhanced chemical vapor deposition system 200 , available from AKT, a division of Applied Materials, Inc., Santa Clara, Calif. The system 200 generally includes a processing chamber 202 coupled to a gas source 204 . The processing chamber 202 has walls 206 and a bottom 208 that partially define a process volume 212 . The process volume 212 is typically accessed through a port (not shown) in the walls 206 that facilitates movement of a substrate 240 into and out of the processing chamber 202 . The walls 206 and bottom 208 are typically fabricated from a unitary block of aluminum or other material compatible with processing. The walls 206 support a lid assembly 210 that contains a pumping plenum 214 that couples the process volume 212 to an exhaust port (that includes various pumping components, not shown).
[0013] A temperature controlled substrate support assembly 238 is centrally disposed within the processing chamber 202 . The support assembly 238 supports a glass substrate 240 during processing. In one embodiment, the substrate support assembly 238 comprises an aluminum body 224 that encapsulates at least one embedded heater 232 .
[0014] Generally, the support assembly 238 has a lower side 226 and an upper side 234 . The upper side 234 supports the glass substrate 240 . The lower side 226 has a stem 242 coupled thereto. The stem 242 couples the support assembly 238 to a lift system (not shown) that moves the support assembly 238 between an elevated processing position (as shown) and a lowered position that facilitates substrate transfer to and from the processing chamber 202 . The stem 242 additionally provides a conduit for electrical and thermocouple leads between the support assembly 238 and other components of the system 200 .
[0015] A bellows 246 is coupled between support assembly 238 (or the stem 242 ) and the bottom 208 of the processing chamber 202 . The bellows 246 provides a vacuum seal between the chamber volume 212 and the atmosphere outside the processing chamber 202 while facilitating vertical movement of the support assembly 238 .
[0016] The support assembly 238 generally is grounded such that RF power supplied by a power source 222 to a gas distribution plate assembly 218 positioned between the lid assembly 210 and substrate support assembly 238 (or other electrode positioned within or near the lid assembly of the chamber) may excite gases present in the process volume 212 between the support assembly 238 and the distribution plate assembly 218 . The RF power from the power source 222 is generally selected commensurate with the size of the substrate to drive the chemical vapor deposition process. The precursor gas or gas mixture in the chamber is energized (e.g., excited) into a plasma by applying radio frequency (RF) power to the chamber from one or more RF sources coupled to the chamber. The excited gas or gas mixture reacts to form a layer of material on a surface of the substrate 240 that is positioned on a temperature controlled substrate support assembly 238 .
[0017] The support assembly 238 additionally supports a circumscribing shadow frame 248 . Generally, the shadow frame 248 prevents deposition at the edge of the glass substrate 240 and support assembly 238 so that the substrate does not stick to the support assembly 238 . The support assembly 238 has a plurality of holes 228 disposed therethrough that accept a plurality of lift pins 250 . The lift pins 250 are typically comprised of ceramic or anodized aluminum.
[0018] The lid assembly 210 provides an upper boundary to the process volume 212 . The lid assembly 210 typically can be removed or opened to service the processing chamber 202 . In one embodiment, the lid assembly 210 is fabricated from aluminum (Al). The lid assembly 210 includes a pumping plenum 214 formed therein coupled to an external pumping system (not shown). The pumping plenum 214 is utilized to channel gases and processing by-products uniformly from the process volume 212 and out of the processing chamber 202 .
[0019] The lid assembly 210 typically includes an entry port 280 through which process gases provided by the gas source 204 are introduced into the processing chamber 202 . The entry port 280 is also coupled to a cleaning source 282 . The cleaning source 282 typically provides a cleaning agent, such as dissociated fluorine, that is introduced into the processing chamber 202 to remove deposition by-products and films from processing chamber hardware, including the gas distribution plate assembly 218 .
[0020] The gas distribution plate assembly 218 is coupled to an interior side 220 of the lid assembly 210 . The gas distribution plate assembly 218 is typically configured to substantially follow the profile of the glass substrate 240 , for example, polygonal for large area flat panel substrates and circular for wafers. The gas distribution plate assembly 218 includes a perforated area 216 through which process and other gases supplied from the gas source 204 are delivered to the process volume 212 . The perforated area 216 of the gas distribution plate assembly 218 is configured to provide uniform distribution of gases passing through the gas distribution plate assembly 218 into the processing volume 212 .
[0021] The gas distribution plate assembly 218 typically includes a diffuser plate (or distribution plate) 258 suspended from a hanger plate 260 . The diffuser plate 258 and hanger plate 260 may alternatively comprise a single unitary member. A plurality of gas passages 262 are formed through the diffuser plate 258 to allow a predetermined distribution of gas passing through the gas distribution plate assembly 218 and into the process volume 212 . The hanger plate 260 maintains the diffuser plate 258 and the interior surface 220 of the lid assembly 210 in a spaced-apart relation, thus defining a plenum 264 therebetween. The plenum 264 allows gases flowing through the lid assembly 210 to uniformly distribute across the width of the diffuser plate 258 so that gas is provided uniformly above the center perforated area 216 and flows with a uniform distribution through the gas passages 262 .
[0022] FIG. 2B is a partial sectional view of an exemplary diffuser plate 258 . For example, for a 696468 mm 2 (e.g. 762 mm×914 mm) diffuser plate, the diffuser plate 258 includes about 12,000 gas passages 262 . For larger diffuser plates used to process larger flat panels, the number of gas passages 262 could be as high as 100,000. The gas passages 262 are generally patterned to promote uniform deposition of material on the substrate 240 positioned below the diffuser plate 258 . Referring to FIG. 2B , in one embodiment, the gas passage 262 is comprised of a restrictive section 422 , and a conical opening 406 . The restrictive section 422 passes from the first side 418 of the diffuser plate 258 and is coupled to the conical opening 406 . The conical opening 406 is coupled to the restrictive section 422 and flares radially outwards from the restrictive section 422 to the second side 420 of the diffuser plate 258 . The second side 420 faces the surface of the substrate. The flaring angle 416 of the conical opening 406 is between about 20 to about 35 degrees.
[0023] The flared openings 406 promote plasma ionization of process gases flowing into the processing region 212 . Moreover, the flared openings 406 provide larger surface area for hollow cathode effect to enhance plasma discharge. In one embodiment, the diameter of the restrictive section 422 is 1.40 mm (or 0.055 inch). The length of the restrictive section 422 is 14.35 mm (or 0.565 inch). The conical opening 406 has a diameter of 7.67 mm (or 0.302 inch) on the second side 420 of the diffuser plate 258 . The flaring angle of the flared opening 406 is 22 degree. The length of the flared opening is 16.13 mm (or 0.635 inch).
[0024] As the size of substrate continues to grow in the TFT-LCD industry, especially, when the substrate size is at least about 100 cm by about 100 cm (or about 10,000 cm 2 ), film thickness uniformity value of some films becomes too large to meet the stringent requirement of some device manufacturers for large area plasma-enhanced chemical vapor deposition (PECVD). For example, gate dielectric thickness uniformity requirement is below 2-3% for some manufacturers and could not be achieved by the existing designs of gas distribution plates.
[0025] Therefore, there is a need for an improved gas distribution plate assembly that improves the control of film properties, such as film thickness uniformity.
SUMMARY OF THE INVENTION
[0026] Embodiments of a gas distribution plate for distributing gas in a processing chamber are provided. In one embodiment, a gas distribution plate assembly for a plasma processing chamber having a cover plate comprises a diffuser plate having an upstream side, a downstream side facing a processing region, and a plurality of gas passages formed through the diffuser plate, and a baffle plate, placed between the cover plate of the process chamber and the diffuser plate, having a plurality of holes extending from the upper surface to the lower surface of the baffle plate, wherein the plurality of holes have at least two sizes.
[0027] In another embodiment, a plasma processing chamber with a cover plate comprises a diffuser plate having an upstream side, a downstream side facing a processing region, and a plurality of gas passages formed through the diffuser plate, and a baffle plate, placed between the cover plate of the process chamber and the diffuser plate, having a plurality of holes extending from the upper surface to the lower surface of the baffle plate, wherein the plurality of holes have at least two sizes.
[0028] In another embodiment, a method of depositing a thin film on a substrate comprises placing a substrate in a process chamber having a cover and with a diffuser plate having an upstream side, a downstream side facing a processing region, and a plurality of gas passages formed through it, and a baffle plate, placed between the cover plate of the process chamber and the diffuser plate, having a plurality of holes extending from the upper surface to the lower surface of the baffle plate, wherein the plurality of holes have at least two sizes, flowing process gas(es) through the baffle plate and the diffuser plate toward a substrate supported on a substrate support, creating a plasma between the diffuser plate and the substrate support, and depositing a thin film on the substrate in the process chamber.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] The teachings of the present invention can be readily understood by considering the following detailed description in conjunction with the accompanying drawings, in which:
[0030] FIG. 1 (Prior Art) depicts a cross-sectional schematic view of a bottom gate thin film transistor.
[0031] FIG. 2A (Prior Art) is a schematic cross-sectional view of an illustrative processing chamber having a gas diffuser plate.
[0032] FIG. 2B (Prior Art) depicts a cross-sectional schematic view of the gas diffuser plate of FIG. 2A .
[0033] FIG. 3A is a schematic cross-sectional view of an illustrative processing chamber having an exemplary gas diffuser plate and an exemplary baffle plate.
[0034] FIG. 3B depicts a cross-sectional schematic view of the exemplary baffle plate placed between a top plate and the exemplary diffuser plate.
[0035] FIG. 4 shows the process flow of depositing a thin film on a substrate in a process chamber with a diffuser plate.
[0036] FIG. 5A shows the tetraethylorthosilicate (TEOS) oxide deposition rate measurement across a 920 mm by 730 mm substrate collected from deposition with a gas distribution assembly without a baffle plate.
[0037] FIG. 5B shows the TEOS oxide deposition rate measurement across a 920 mm by 730 mm substrate collected from deposition with a gas distribution assembly with a baffle plate with small pinholes.
[0038] FIG. 5C shows a top view of a baffle plate with symmetrically distributed small pinholes.
[0039] FIG. 5D shows the TEOS oxide deposition rate measurement across a 920 mm by 730 mm substrate collected from deposition with a gas distribution assembly with a baffle plate with small pinholes and large holes.
[0040] FIG. 5E shows a top view of a baffle plate with symmetrically distributed large holes.
[0041] FIG. 6A shows the SiN deposition rate measurement across a 920 mm by 730 mm substrate collected from deposition with a gas distribution assembly without a baffle plate.
[0042] FIG. 6B shows the SiN deposition rate measurement across a 920 mm by 730 mm substrate collected from deposition with a gas distribution assembly with a baffle plate with small pinholes and large holes.
[0043] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures.
DETAILED DESCRIPTION
[0044] The invention generally provides a gas distribution assembly for providing gas delivery within a processing chamber. The invention is illustratively described below in reference to a plasma enhanced chemical vapor deposition system configured to process large area substrates, such as a plasma enhanced chemical vapor deposition (PECVD) system, available from AKT, a division of Applied Materials, Inc., Santa Clara, Calif. However, it should be understood that the invention has utility in other system configurations such as etch systems, other chemical vapor deposition systems and any other system in which distributing gas within a process chamber is desired, including those systems configured to process round substrates.
[0045] We have determined that the uniformity of reactive plasma distribution in the process chamber can be improved by adding a baffle plate 257 to the gas distribution plate assembly 218 , as shown in FIG. 3A . The baffle plate 257 is placed between the cover plate 303 of the lid assembly 210 and the gas diffuser plate 258 . The baffle plate 257 is typically configured to substantially follow the profile of the gas distribution plate 258 , for example, polygonal for large area flat panel substrates and circular for wafers. The holes 253 across the baffle plate 257 and the gas passages 262 across the gas diffuser plate 258 together affect the gas distribution from the gas entry port 280 . FIG. 3B is a drawing that shows the relationship between the cover plate 303 , the baffle plate 257 and the diffuser plate 258 . The baffle plate 257 is typically fabricated from stainless steel, aluminum (Al), anodized aluminum, nickel (Ni) or other RF conductive material. The baffle plate 257 could be cast, brazed, forged, hot iso-statically pressed or sintered. The baffle plate 257 is configured with a thickness that maintains sufficient flatness across the aperture 266 as not to adversely affect substrate processing. The baffle plate 257 also should be kept relatively thin to prevent excessive drilling time to make holes 253 . In one embodiment, the thickness of the baffle plate 257 is between about 0.02 inch to about 0.20 inch. Since the baffle plate 257 works together with the gas diffuser plate 258 to affect the gas distribution uniformity, the distance “D” between the baffle plate 257 and the gas diffuser plate 258 should be kept small. In one embodiment, the distance “D” is below 0.6 inch. If the distance between the two plates is too large, the affect of the baffle plate 257 would diminish, since the gas or gas mixture would redistribute between the two plates.
[0046] The holes 253 across the baffle plate 257 have more than one size. The holes 253 should distribute symmetrically across the baffle plate to increase the gas distribution uniformity. The holes 253 are typically cylindrical; however, other shapes of holes can also be used. Different sizes of holes could be placed across the baffle plate 257 symmetrically to control the gas distribution uniformity. In one embodiment, the baffle plate 257 has holes 253 with at least two sets of sizes, small pinholes and large holes. The small pinholes are needed to transport high-flow-rate gas mixture from upstream to downstream without building up pressure in the blocker plate upstream plenum 264 . Building up pressure in the blocker plate upstream plenum 264 could result in recombination of reactive radicals, such as the fluorine radicals from the remote plasma clean source. Large holes are used to adjust the film deposition thickness uniformity and profile across the substrate. These large holes alone are not enough for high gas flow, such as flow rate >3000 sccm, to pass through. For example during remote plasma clean (RPS) clean, the cleaning gas flow rate is about 4000 sccm. Sufficient numbers of small pinholes would prevent the pressure build up in the block plate upstream plenum 264 . The small pinholes could be all at one size or at more than one size. In one embodiment, the diameters of the small pinholes are kept below 1.27 mm (or 0.05 inch). The large holes could also be at one size or at more than one size. In one embodiment, the diameters of these the large holes are between about 1.59 mm (or 1/16 inch) to about 6.35 mm (or ¼ inch).
[0047] The total cross-sectional areas of the small pinholes should be kept to larger than 1 square inch to ensure enough pass-through for the gas mixture, such as cleaning gas species generated by a RPS (remote plasma source) unit. In one embodiment, the diameters of the large holes are kept greater than 1.56 mm (or 1/16 inch).
[0048] The process of depositing a thin film in a process chamber is shown in FIG. 4 . The process starts at step 401 by placing a substrate in a process chamber with a gas distribution assembly. Next at step 402 , flow process gas(es) through the gas distribution assembly toward a substrate supported on a substrate support. Then at step 403 , create a plasma between the gas distribution assembly and the substrate support. At step 404 , deposit a thin film on the substrate in the process chamber.
[0049] FIG. 5A shows a thickness profile of a TEOS oxide film across a glass substrate. The size of the substrate is 920 mm by 730 mm. The gas distribution assembly does not include a baffle plate. The diffuser plate has diffuser holes with design shown in FIG. 2B . The diameter of the restrictive section 422 is 1.40 mm (or 0.055 inch). The length of the restrictive section 422 is 14.35 mm (or 0.565 inch). The conical opening 406 has a diameter of 7.67 mm (or 0.302 inch) on the second side 420 of the diffuser plate 258 . The flaring angle of the flared opening 406 is 22 degrees. The length of the flared opening is 16.13 mm (or 0.635 inch). The TEOS oxide film is deposited using 850 sccm TEOS, 300 sccm He, and 10000 sccm O 2 , under 0.95 Torr, and 2700 watts source power. The spacing between the diffuser plate 258 and the substrate support assembly 238 is 11.94 mm (or 0.47 inch). The process temperature is maintained at about 400° C. The deposition rate is averaged to be 1800 Å/min and the thickness uniformity (with 15 mm edge exclusion) is about 5.5%, which is higher than the 2-3% manufacturing specification for some manufacturers. The thickness profile shows a center thick and edge thick profile, or “W shape” profile.
[0050] FIG. 5B shows a thickness profile of a TEOS oxide film across a glass substrate. The size of the substrate is 920 mm by 730 mm. The gas distribution assembly includes a baffle plate, in addition to the diffuser plate used for FIG. 5A deposition. The baffle plate only has small, cylindrical pinholes. The diameter of the small pinholes is 0.41 mm (or 0.016 inch). They are totally 8426 holes across the baffle plate. FIG. 5C shows the pattern of the pinholes on the baffle plate. The pinholes are radially and symmetrically distributed from the center of the blocker plate to the edges of the blocker plate. In one embodiment, the density of the pinholes near the center of the blocker plate is higher than the density of pinholes near the edges of the blocker plate.
[0051] The distance between the baffle plate and the diffuser plate is 12.55 mm (or 0.494 inch). The thickness of the baffle plate is 1.37 mm (or 0.054 inch). The diffuser plate is similar to the one used for FIG. 5A deposition. The spacing between the diffuser plate and the support assembly is 11.94 mm (or 0.47 inch). The deposition condition and process are the same as those of FIG. 5A . The deposition rate is found to average about 1800 Å/min and the thickness uniformity (with 15 mm edge exclusion) is about 5.0%, which is still higher than the manufacturing specification. The thickness profile still shows a center thick and edge thick profile, or “W shape” profile. The results show that a baffle plate with small pinholes only does not improve the TEOS uniformity.
[0052] FIG. 5D shows a thickness profile of a TEOS oxide film across a glass substrate. The size of the substrate is 920 mm by 730 mm. The gas distribution assembly includes a baffle plate. The baffle plate only has small, cylindrical pinholes, and large, cylindrical holes. The diameter of the small pinholes is 0.41 mm (or 0.016 inch). There are 8426 pinholes across the baffle plate. The size and location of the small pinholes are similar to the small pinholes on the baffle plate used for FIG. 5B deposition. FIG. 5C shows the pattern of the small pinholes on the baffle plate. The baffle plate also has large holes with diameters 1.59 mm (or 1/16 inch), 3.18 mm (or ⅛ inch), and 4.76 mm (or 3/16 inch). There are 14 holes with diameter of 1.59 mm, 4 holes with diameter of 3.18 mm and 4 holes with diameter of 4.76 mm. Their distribution across the baffle plate is shown in FIG. 5E . The distance between the baffle plate and the diffuser plate is 12.55 mm (or 0.494 inch). The thickness of the baffle plate is 1.37 mm (or 0.054 inch). The diffuser plate is similar to the one used for deposition in FIGS. 5A and 5B . The spacing between the diffuser plate and the support assembly is 11.94 mm (or 0.47 inch). The deposition condition and process are the same as those of FIG. 5A and FIG. 5B . The deposition rate is found to be averaged about 1800 Å/min and the thickness uniformity (with 15 mm edge exclusion) is about 1.8%, which is within the manufacturing specification. The thickness profile shows a smooth profile from center to edge. The results show that a baffle plate with small pinholes and large holes improve the TEOS uniformity.
[0053] The addition of the baffle plate does not appear to affect other TEOS oxide film properties. Table 1 compares stress, refractive index (RI), Si—O peak position, and wet etch rate.
[0000]
TABLE 1
Comparison of film properties on substrates
deposited with TEOS Oxide film.
Stress
Si—O
WER
Baffle Plate
RI
(E9Dynes/cm 2 )
Peak Position
(Å/min)
None
1.46
C0.7
1080
2043
small pinholes
1.46
C0.8
1080
2058
small pinholes +
1.46
C0.6
1080
2093
large holes
[0054] The refractive index (RI), film stress, Si—O peak position data and wet etch rate (WER) data all show similar values for three types of baffle plates. The Si—O peak position is measured by FTIR (Fourier Transform Infrared Spectroscopy). Wet etch rate is measured by immersing the samples in a BOE (buffered oxide etch) 6:1 solution.
[0055] In addition to TEOS oxide film, the effect of the baffle plate on other types of dielectric film has also been investigated. FIG. 6A shows the SiN film deposition rate across the substrate surface, using a gas distribution assembly that is the same as the gas distribution assembly of FIG. 5A (without a baffle plate). The SiN film is deposited using 810 sccm SiH 4 , 6875 sccm NH 3 , and 9000 sccm N 2 , under 1.60 Torr, and 3400 watts source power. The spacing between the diffuser plate and the support assembly is 28.83 mm (or 1.135 inch). The process temperature is maintained at about 400° C. The deposition rate is averaged to be about 1850 Å/min and the thickness uniformity (with 15 mm edge exclusion) is about 2.5%, which is within the manufacturing specification. The thickness profile shows a smooth profile from center to edge.
[0056] FIG. 6B shows the SiN film deposition rate across the substrate surface, using a gas distribution assembly that is the same as the gas distribution assembly of FIG. 5D (with a baffle plate with small pinholes and large holes). The SiN film is deposited using 810 sccm SiH 4 , 6875 sccm NH 3 , and 9000 sccm N 2 , under 1.60 Torr, and 3400 watts source power. The spacing between the diffuser plate and the support assembly is 28.83 mm (or 1.135 inch). The process temperature is maintained at about 400° C. The deposition rate is averaged to be about 1850 Å/min and the thickness uniformity (with 15 mm edge exclusion) is about 2.5%, which is within the manufacturing specification. The thickness profile also shows a smooth profile from center to edge.
[0057] The results show that SiN film thickness across the substrate is not affected by the addition of a baffle plate with small pinholes and large holes such as the one used for depositing TEOS film in FIG. 5D and described in FIG. 5C and FIG. 5E . The addition of the baffle plate does not affect other SiN film properties. Table 2 compares stress, refractive index (RI), N—H/Si—H ratio, and wet etch rate.
[0000]
TABLE 2
Comparison of film properties on substrates
deposited with SiN film.
Stress
WER
Baffle Plate
RI
(E9Dynes/cm 2 )
N—H/Si—H
(Å/min)
None
1.87
T5.7
19.6/16.8
1878
small pinholes +
1.87
T5.3
19.7/16.3
1849
large holes
[0058] The refractive index (RI), film stress, N—H/Si—H ratio data and wet etch rate (WER) data all show similar values for substrates deposited with or without a baffle plate with small pinholes and large holes as used in FIG. 5D deposition and described in FIG. 5C and FIG. 5E . The N—H/Si—H ratio is measured by FTIR. Wet etch rate is measured by immersing the samples in a BOE (buffered oxide etch) 6:1 solution.
[0059] The results show that using a baffle plate with small pinholes and large holes improves the TEOS oxide thickness uniformity and does not affect the other film properties of the TEOS film. The results also show that using the same baffle plate with small pinholes and large holes does not affect the film thickness uniformity and other film properties of SiN film. The difference could be due to the fact that TEOS is a liquid source and also has a higher molecular weight.
[0060] Gas distribution plates of gas distribution plate assembly that may be adapted to benefit from the invention described above are described in commonly assigned U.S. patent application Ser. No. 09/922,219, filed Aug. 8, 2001 by Keller et al., U.S. patent application Ser. Nos. 10/140,324, filed May 6, 2002 by Yim et al., and 10/337,483, filed Jan. 7, 2003 by Blonigan et al., U.S. Pat. No. 6,477,980, issued Nov. 12, 2002 to White et al., U.S. patent application Ser. No. 10/417,592, filed Apr. 16, 2003 by Choi et al., and U.S. patent application Ser. No. 10/823,347, filed on Apr. 12, 2004 by Choi et al., which are hereby incorporated by reference in their entireties.
[0061] Although the processes and examples used are for making thin film transistor devices, the concept of the invention can be used for making OLED application, solar panel substrates and other applicable devices.
[0062] Although several preferred embodiments which incorporate the teachings of the present invention have been shown and described in detail, those skilled in the art can readily devise many other varied embodiments that still incorporate these teachings. | Embodiments of a gas distribution plate for distributing gas in a processing chamber for large area substrates are provided. The embodiments describe a gas distribution plate assembly for a plasma processing chamber having a cover plate comprises a diffuser plate having an upstream side, a downstream side facing a processing region, and a plurality of gas passages formed through the diffuser plate, and a baffle plate, placed between the cover plate of the process chamber and the diffuser plate, having a plurality of holes extending from the upper surface to the lower surface of the baffle plate, wherein the plurality of holes have at least two sizes. The small pinholes of the baffle plate are used to allow sufficient pass-through of gas mixture, while the large holes of the baffle plate are used to improve the process uniformity across the substrate. | 2 |
CROSS REFERENCE TO A RELATED APPLICATION
[0001] This application is a continuation-in-part of U.S. patent application Ser. No. 09/202,652 which has been allowed.
BACKGROUND OF THE INVENTION
[0002] In wiper blades, the support element for the entire field swept by the wiper blade is intended to assure the most uniform possible distribution of the wiper blade contact pressure, originating in the wiper arm, against the window. By means of a suitable curvature of the unloaded support element—that is, when the wiper blade is not resting on the window—the ends of the wiper strip, which in wiper blade operation is pressed completely against the window, are located by the then tensed support element toward the window, even if the radii of curvature of spherically curved vehicle windows change in every wiper blade position. That is, the curvature of the wiper blade must be somewhat greater than the greatest curvature measured in the wiping field of the window to be wiped. the support element thus replaces the complicated support bracket construction with two spring rails disposed in the wiper strip of the kind used in conventional wiper blades.
[0003] In a known wiper blade of this type (German Patent Disclosure DE 26 14 457), the connection device is integrally joined to the support element. This may possibly be of secondary importance as long as the support element is made from a plastic which is therefore made by filling a suitable mold. However, if the support element is to be made of metal, then two demands directly contract one another. On the one hand, the support element should have good spring properties, but on the other the attachments of the connection device should be easily bent by approximately 90° out of the plane of the support element and fixed in that position, so that the loads occurring in operation between the wiper blade and the wiper arm can be absorbed on stop faces of these attachments. These two demands are virtually impossible to meet unless disadvantageous compromises in the choice of material are made.
[0004] In another known wiper blade (German Patent Disclosure DE 12 47 161), the support element is provided with a connection device as a separate component. This connection device is solidly joined to the support element with the aid of rivets. The requisite bores in the support element, however, lead to an undesired, because uncontrollable, change in the support element tension, so that a satisfactory window wiping result cannot be attained.
SUMMARY OF THE INVENTION
[0005] Accordingly, it is an object of present invention to provide a wiper blade for motor vehicle windows, which is a further improvement of the existing wiper blades.
[0006] In keeping with these objects and with others which will become apparent hereinafter, one feature of present invention resides, briefly stated, in a wiper blade, in which a connection device for a driven wiper arm has a base which rests flatly on a side remote from the window of a band-shaped support element, and is connected to the band-shaped support element by a welding connection.
[0007] In the inventive wiper blade, a choice of materials that suits the demands made of the particular component can be made for both the support element and the connection device. The joining of the two components to one another is done easily and economically by means of a welded connection. Further assembly steps can be omitted. Tests have shown that a welded connection does not impair, or insignificantly impairs, the contact pressure distribution by the support element and thus the outcome of window wiping.
[0008] If the support element and the connection device of the wiper blade are of metal, it can be expedient if the welded connection is a resistance weld.
[0009] Particularly in a wiper blade in which both the support element and the connection device are made of a plastic, operationally reliable and economical fastening of the connection device to the support element can be attained by means of ultrasonic welding.
[0010] The welding itself, both in resistance welding and ultrasonic welding, can be embodied as preferably multiple spot welds.
[0011] In a wiper blade of which major demands are made in terms of the load, however, the welded connection can also be embodied by a plurality of linear welds; with a view to the specifications to be met in terms of pressure distribution, the welds may extend either crosswise to the longitudinal direction or longitudinally of the band like support element.
[0012] A connection device that can be adapted without difficulty in view of the wiper arm design is obtained if it rests flatly with the base on the side of the bandlike support element remote from the window.
[0013] Especially good lateral guidance and holding of the two components to be joined together is attained if the protrusions are embodied as strips, which extend longitudinally of the support element.
[0014] A further-improved, stable holding of the connection device to the support element is attained if on the free ends of the strips, clawlike attachments oriented counter to one another are disposed, and the spacing between the clawlike attachments and the outside, remote from the legs of the base of the U is adapted to the thickness of the support element.
[0015] For positioning the connection device on the support element in the longitudinal direction thereof, the connection device can have at least one shoulder, pointing longitudinally of the support element, with which shoulder a counterpart shoulder of the support element is associated. The result is accordingly a positive positioning aid that becomes operative before the welding operation.
[0016] Absolute securing of the mounted position of the connection device on the support element is obtained if the connection device has at least two shoulders, pointing in opposite directions, with each of which the counterpart shoulder of the support element is associated.
[0017] Expediently, the shoulders of the connection device are embodied on a protrusion of the connection device, and the counterpart shoulders and are embodied on a recess, associated with the protrusion of the support element.
[0018] Further advantages features and refinements of the invention are described in the ensuing description of embodiments shown in the drawing.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] [0019]FIG. 1 is a side view of a wiper blade according to the invention;
[0020] [0020]FIG. 2 is a plan view on the wiper blade of FIG. 1;
[0021] [0021]FIG. 3 is a view from below, on a larger scale of a support element that is part of the wiper blade and is provided with a first embodiment of the connection device;
[0022] [0022]FIG. 4 is a section taken along the line IV-IV through the arrangement of FIG. 3;
[0023] [0023]FIG. 5 is a view from below, on a larger scale, of a support element that is part of the wiper blade and is provided with a second embodiment of the connection device;
[0024] [0024]FIG. 6 is a section taken along the line VI-VI through the arrangement of FIG. 5;
[0025] [0025]FIG. 7 is a view from below, on a larger scale, of a support element that is part of the wiper blade and is provided with a third embodiment of the connection device; and
[0026] [0026]FIG. 8, a section taken along the line VIII-VIII through the arrangement of FIG. 7.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0027] A wiper blade 10 shown in FIGS. 1 and 2 has an elongated, spring-elastic support element 12 , to the underside of which an elongated, rubber-elastic wiper strip 14 is secured parallel to the longitudinal axis. A connection device 16 , with the aid of which the wiper blade can be detachably joined to a driven wiper arm 18 , is disposed on the support element, which can also be called a spring rail, in the middle portion thereof. A hook acting as a counterpart connection means is formed on the free end 20 of the wiper arm 18 and clasps a pivot pin 22 that belongs to the connection device 16 of the wiper blade. The securing between the wiper arm 18 and the wiper blade 10 is performed by securing means known per se and not shown in further detail, which are embodied as an adapter.
[0028] The wiper arm 18 and thus also the hook on its end 20 are loaded in the direction of the arrow 24 toward the window to be wiped, whose surface to be wiped is represented in FIG. 1 by a dot-dashed line 26 . Since the dot-dashed line 26 is intended to represent the greatest curvature of the window surface, it is clearly apparent that the curvature of the wiper blade, resting with both its ends on the window, is greater than the maximum window curvature. The wiper blade presses with the contact pressure (arrow 24 ) presses over its entire length with its wiper lip 28 against the window surface 26 . In the process, a tensing builds up in the spring-elastic support element 12 that assures proper contact of the wiper strip 14 , or its wiper lip 28 , over its entire length on the window. The connection between the support element 12 and the connection device 16 will now be explained in further detail in terms of FIGS. 3 and 4; 5 and 6 ; and 7 and 8 .
[0029] In the first embodiment of the invention, shown in FIGS. 3 and 4, the connection device 16 is pressed flatly, with the outside of its base 30 , against the surface, remote from the window to be wiped, of the bandlike support element 12 . The legs 32 and 34 of the U of the connection device 16 extend on the side of the base 30 of the U remote from the support element 12 . The pivot pin 22 is supported in the legs 32 and 34 of the U. The fastening of the connection device 16 to the support element 12 is done with the aid of a welded connection which will be described in further detail hereinafter.
[0030] While in the drawings the connection device 16 is substantially U-shaped cross-section, this is not necessary for the present invention. The connection device 16 must have only the base 30 or a base-like part, which can be flatly placed on the support element 12 and connected with the latter.
[0031] As a positioning aid, the base 30 of the connection device has a protrusion 38 , extending from the side remote from the legs 32 and 34 of the U, and this protrusion has two shoulders 40 and 42 pointing in opposite directions—in the longitudinal direction of the support element 12 . These shoulders 40 and 42 are each assigned a respective counterpart shoulder 44 and 46 of the support element, and the counterpart shoulders are embodied at a recess 48 of the support element 12 . Because these shoulders point in the longitudinal direction of the support element, a positive connection is obtained between the support element 12 and the connection device 16 longitudinally of the support element. This positive engagement acts as a positioning aid when the welded connection is to be made.
[0032] In the exemplary embodiment of FIGS. 5 and 6, which shows a refinement of the arrangement of FIGS. 3 and 4, two striplike protrusions 60 and 62 are disposed, spaced apart from one another by a distance adapted to the width 64 of the support element 12 , on the side of the base 30 of the U remote from the legs 32 and 34 of the U. The striplike protrusions 60 and 62 extending longitudinally of the support element 12 from lateral guides, which secure the position of the connection device 16 on the support element 12 crosswise to its longitudinal extent.
[0033] The embodiment of FIGS. 7 and 8 is based on the embodiment of FIGS. 5 and 6. In a departure from that embodiment, for further simplification of preassembly, the striplike protrusions 160 and 162 are provided, on their free ends remote from the base 30 of the U, with clawlike attachments 166 and 168 pointing in opposite directions from one another. The spacing between the outside of the base 30 of the U, remote from the legs 32 , 34 of the U, and the side oriented toward the base of the attachments 166 and 168 is adapted to the thickness 170 of the support element 12 . This adaptation is made such that just as in the embodiment of FIGS. 5 and 6, an easy but largely play-free relative motion between the two components 12 and 16 is possible.
[0034] It is shown in the embodiment of FIGS. 3 and 4 that the welded connectoin comprises a plurality of spotlike welds 36 . In the embodiment of FIGS. 5 and 6, the welded connection has a plurality of linear welds 136 , whose longitudinal extent is crosswise to the longitudinal direction of the support element 12 . In the embodiment shown in FIGS. 7 and 8, the welds 236 are also linear. In a departure from the arrangement in FIGS. 5 and 6, in this embodiment of the invention the linear welds 236 are in the longitudinal direction of the support element 12 .
[0035] The connection device 16 can be welded to the support element in one point or in one strip in a first region, and claws can be provided in which the connection device is additionally fixed to the support element, similarly to the claws shown in FIG. 8. With such a construction, the support element can make, while wiping the windshield having a changing curvature, a movement relative to the connection device which is perpendicular to the windshield. As a result, there is no tension between the connection device and the support element during the wiping movement.
[0036] In practice, it has been found that the few welds 36 or 136 or 236 assure an operationally safe and secure connection between the support element 12 and the connection device 116 . Any impairment to the spring properties of the support element is kept within such narrow limits that in view of the wiping results to be sought it can be practically ignored. It does not matter whether the spring element 12 and the connection device 16 are each of metal or are of plastic. It is illuminating that in this case even different kinds of plastics can be joined together, which in view of their properties meet the demands made of them. In the case of a metal version, a resistance weld can be expedient, while in a plastic version an ultrasonic weld can have advantages.
[0037] It should also be noted that the positive connection described in the embodiment of FIGS. 3 and 4—that is, the protrusion 38 with its shoulders 40 and 42 and the recess 48 with its counterpart shoulders 44 and 46 —can also be used in the embodiments of FIGS. 5 and 6 and FIGS. 7 and 8. It is also worth noting that the bandlike support element 12 in the exemplary embodiments is indeed made in one part, but it can also comprise multiple parts without thereby departing from the scope of the present invention.
[0038] Nor need the arrangement of welds 36 , 136 and 236 be absolutely selected as shown in FIGS. 3, 5 and 7 . On the contrary, it is also conceivable for them ti be disposed on the protrusions 60 , 62 , and 160 , 162 , or on the attachments 166 , 168 .
[0039] It should also be pointed out that the shape of the welds 36 or 136 or 236 is independent of how the connection device 16 is embodied. The disposition and shaping of the welds are merely shown as an example in FIGS. 3, 5 and 7 .
[0040] It is clear that—in a departure from the exemplary embodiment shown—the counterpart shoulders 44 , 46 need not necessarily be embodied on a recess, open at the edge, of the support element. In view of the operating tension present in the support element 12 and oriented toward the window 26 , it may be advantageous to dispose the counterpart shoulders in a region of the support element 12 that is invulnerable in this respect. this can be done for instance in the region of the support element 12 facing the central region of the base of the U. In that case, the counterpart shoulders are embodied on an opening that is closed all the way around. Accordingly, the shoulders cooperating with them should then be placed on the connection device.
[0041] It should also be remembered that the arrangement of the positioning aid described can be employed independently of whatever way in which the connection device is to be joined to the support element. | A wiper blade for motor vehicle windows has an elongated spring-elastic support element, an elongated, rubber elastic wiper strip which is pressable against a window to be wiped and is held substantially parallel to a longitudinal axis by the elongated, spring-elastic support element, a connection device for a driven wiper arm, the connection device being loaded toward the window and secured to a middle portion of the spring-elastic support element, remote from the window, the connection device being formed as a component which is separate from the support element, and a welding connection which connects the connection device with the support element, the support element being band-shaped, the connection device having a base resting flatly on a side remote from the window of the band-shaped support element and connected to the band-shaped supporting element by the welding connection. | 1 |
This is the Section 371 National Phase application of International Application PCT/JP97/03743, filed Oct. 16, 1997.
TECHNICAL FIELD
The present invention relates to a triangular-pyramidal cube-corner retroreflective sheet having a novel structure. More minutely, the present invention relates to a cube-corner retroreflective sheet in which triangular-pyramidal reflective elements having a novel structure are arranged in a close-packed state.
Still more minutely, the present invention relates to a cube-corner retroreflective sheet constituted with triangular-pyramidal cube-corner retroreflective elements (hereafter referred to as triangular-pyramidal reflective elements or merely, elements) useful for signs including traffic signs and construction work signs, license plates of automobiles and motorcycles, safety materials of clothing and life preservers, markings of signboards, and reflectors of visible-light, laser-beam, and infrared-ray reflective sensors.
Still more minutely, the present invention relates to a triangular-pyramidal cube-corner retroreflective sheet in which triangular-pyramidal cube-corner retroreflective elements protruded on one common base plane (X-X') are arranged on the base plane in a close-packed state so as to face each other by sharing one common base edge on the base plane (X-X') with each other, the base plane (X-X') is one common plane including a plurality of the base edges (x, x, . . . ) shared by the triangular-pyramidal retroreflective elements, two these triangular-pyramidal retroreflective elements facing each other form a pair of elements having the substantially same shape facing each other so as to be respectively substantially symmetric to planes (Y-Y', Y-Y', . . . ) vertical to the base plane including the common base edges (x, x, . . . ) on the base plane (X-X'), the triangular-pyramidal retroreflective elements are formed with substantially same pentagonal lateral faces (c 1 , c 2 ) using the common base edges (x, x, . . . ) as one side and substantially same quadrangular lateral faces (a 1 , b 1 ; a 2 , b 2 ) substantially perpendicularly intersecting the face c 1 or c 2 using two upper sides of the face c 1 or c 2 using apexes (H 1 , H 2 ) of the triangular-pyramidal retroreflective elements as starting points as one side respectively, sharing one of ridge lines of the triangular-pyramidal retroreflective elements and using the ridge line as one side and the height (h') from the apexes (H 1 , H 2 ) of the triangular-pyramidal retroreflective elements up to the base plane (X-X') including the base edges (x, x, . . . ) of the pentagonal lateral faces (c 1 , c 2 ) of the triangular-pyramidal retroreflective elements is substantially larger than the height (h) from the apexes (H 1 , H 2 ) of the triangular-pyramidal retroreflective elements up to a substantially horizontal plane (virtual plane Z-Z') including base edges (z, w) of other lateral faces (a 1 , b 1 ; a 2 , b 2 ) of the triangular-pyramidal retroreflective elements.
BACKGROUND ART
A retroreflective sheet for reflecting incoming light toward a light source has been well known so far and the sheet using its retroreflective characteristic is widely used in the above fields. Particularly, a cube-corner retroreflective sheet using the retroreflective theory of a cube-corner retroreflective element such as a triangular-pyramidal reflective element is extremely superior to a conventional retroreflective sheet using a micro glass beads in retroreflectivity and its purpose has been expanded year by year because of its superior retroreflective performance.
However, though a conventionally-publicly-known triangular-pyramidal retroreflective element shows a preferable retroreflectivity when the angle formed between the optical axis of the element (axis passing through the apex of the triangular pyramid of the triangular-pyramidal retroreflective element equally separate from three faces constituting a triangular-pyramidal cube-corner retroreflective element and intersecting each other at an angle of 90°) and an incident light (the angle is hereafter referred to as entrance angle) is kept in a small range, the retroreflectivity rapidly deteriorates as the entrance angle increases (that is, the entrance angle characteristic deteriorates). Moreover, a light entering the triangular-pyramidal retroreflective element face at an angle less than a critical angle (α c ) satisfying an internal total-reflection condition determined by the ratio between the refractive index of a transparent medium constituting the triangular-pyramidal retroreflective element and the refractive index of air penetrates into the back of the element without totally reflecting on the interface of the element. Therefore, a retroreflective sheet using a triangular-pyramidal reflective element generally has a disadvantage that it is inferior in entrance angularity.
However, because a triangular-pyramidal retroreflective element can reflect light in the light incoming direction almost over the entire surface of the element, reflected light does not reflect by dispersing at a wide angle due to aberration differently from the case of a micro-glass-ball reflective element. However, the narrow dispersion angle of the reflected light practically easily causes a trouble that, when the light emitted from a head lamp of an automobile is retro-reflected on a traffic sign, the retro-reflected light hardly reaches, for example, a driver present at a position distant from the axis of the retro-reflected light. Particularly when the distance between an automobile and a traffic sign decreases, the above trouble more-frequently occurs because the angle formed (observation angle) between the entrance axis of a light ray and the axis (observation axis) connecting a driver and a reflective point increases (that is, the observation angularity deteriorates).
For the above cube-corner retroreflective sheet, particularly for a triangular-pyramidal cube-corner retroreflective sheet, many proposals have been known so far and various improvements and studies are performed.
For example, Jungersen's U.S. Pat. No. 2,481,757 discloses a retroreflective sheet constituted by arranging retroreflective elements of various shapes on a thin sheet and a method for manufacturing the sheet. Triangular-pyramidal reflective elements disclosed in the above U.S. patent include a triangular-pyramidal reflective element in which the apex is located at the center of a base-plane triangle and the optical axis does not tilt and a triangular-pyramidal reflective element in which the apex is not located at the center of a base-plane triangle but the optical axis tilts. Moreover, it is described in the U.S. patent to efficiently reflect light toward an approaching automobile. Furthermore, it is described that the size of a triangular-pyramidal reflective element, that is, the depth of the element is 1/10 in (2,540 μm) or less. Furthermore, FIG. 15 in the U.S. patent illustrates a triangular-pyramidal reflective element whose optical axis tilts in the plus (+) direction similarly to the case of a preferred mode of the present invention. The tilt angle (θ) of the optical axis is estimated as approx. 6.5° when obtaining it from the ratio between the longer edge and shorter edge of the base-triangular plane of the illustrated triangular-pyramidal reflective element.
However, the above Jungersen's U.S. patent does not specifically disclose a very small triangular-pyramidal reflective element shown in the present invention or it does not disclose a size or an optical-axis tilt a triangular-pyramidal reflective element must have in order to show superior observation angularity and entrance angularity.
In this specification, the expression "optical axis tilts in the plus (+) direction" represents, as described later, that the optical axis tilts in the direction in which the difference (q-p) between the distance (q) from the intersection (Q) between the optical axis of the triangular-pyramidal reflective element and the base plane (X-X') of the triangular-pyramidal reflective element up to the base edges (x, x, . . . ) shared by the element pair {the distance (q) is equal to the distance from the intersection (Q) up to a plane (Y-Y') vertical to the base plane (X-X') including the base edges (x, x, . . . ) shared by the element pair} and the distance (p) from the intersection (P) between a perpendicular extended from the apex of the element to the base plane (X-X') and the base plane (X-X') up to the base edges (x, x, . . . ) shared by the element pair becomes plus (+). However, when the optical axis tilts in the direction in which (q-p) becomes minus (-), the expression "optical axis tilts in the minus (-) direction" is hereafter used.
Moreover, Stamm's UP Pat. No. 3,712,706 discloses a retroreflective sheet in which so-called equilateral triangular-pyramidal cube-corner retroreflective elements whose base-plane triangles are equilateral triangles are arranged on a thin sheet so that their base planes are brought into a close-packed state on a common plane. Stamm's U.S. patent improves the problem that a retroreflectivity is deteriorated due to increase of an entrance angle through mirror-reflection by vacuum-coating the reflective surface of a reflective element with a metal such as aluminum and the above trouble that the light incoming at an angle of less than an internal total reflection condition passes through the interface between elements and thereby, it does not retro-reflect.
However, because the above Stamm's proposal uses the mirror reflection theory as means for improving the angularity (wide angularity), the proposal easily causes the trouble that the appearance of an obtained retroreflective sheet becomes dark or the reflection brightness easily deteriorates because a metal such as aluminum or silver used for the mirror surface is oxidized due to incoming of water or air while it is used. Moreover, the proposal does not describe means for improving the angularity (wide angularity) by a tilt of an optical axis at all.
Moreover, Hoopman's European Pat. No. 137,736B1 describes a retroreflective sheet in which triangular-pyramidal cube-corner retroreflective elements with a tilted optical axis whose triangular base-plane are isosceles triangles are arranged on a thin sheet so that their base planes are brought into a close-packed state on a common plane. The optical axis of a triangular-pyramidal cube-corner retroreflective element described in the patent tilts in the minus (-) direction inversely to the tilt direction of the optical axis of a preferred triangular-pyramidal reflective element of the present invention and it is described in the patent that the tilt angle of the optical axis is approx. 7° to 13°.
Furthermore, Szczech's U.S. Pat. No. 5,138,488 discloses a retroreflective sheet in which triangular-pyramidal cube-corner retroreflective elements with a tilted optical axis whose base-plane triangles are isosceles triangles are arranged so that the base planes is brought into a close-packed state on a common plane. In the case of the U.S. patent, it is specified that the optical axis of each of the above triangular-pyramidal retroreflective elements tilts in the direction of a side shared by a pair of retroreflective elements facing each other, the tilt angle of the optical axis ranges between 2° and 5°, and the size of each element ranges between 25 μm and 100 μm.
Furthermore, in the case of European Pat. No. 548,280B1 corresponding to the above patent, it is described that the direction of a tilt of an optical axis includes a side common to a pair of elements, the distance between a plane vertical to a common plane and the apex of an element is not equal to the distance between the point where the optical axis of an element intersects the common plane and the vertical plane, the tilt angle of the optical axis of the element ranges between 2° and 5°, and the size of the element ranges between 25 μm and 100 μm.
As described above, in the case of Szczech's European Pat. No. 548,280B1, the tilt of an optical axis ranges between +2° and +5° and between -2° and -5°. In the case of embodiments of the above Szczech's U.S. patent and European patent, however, only triangular-pyramidal retroreflective elements are specifically disclosed which have optical-axis tilt angles of -8.2°, -9.2°, and -4.3° and an element height (h) of 87.5 μm.
The above-described conventionally publicly-known triangular-pyramidal cube-corner retroreflective elements of Jungersen's U.S. Pat. No. 2,481,757. Stamm's U.S. Pat. No. 3,712,706, Hoopman's European Pat. No. 137,736B1 and Szczech's U.S. Pat. No. 5,138,488 and European Pat. No. 548,280B1 are common in that the base planes of a plurality of triangular-pyramidal reflective elements serving as cores of entrance and reflection of light are present on the same plane. Every retroreflective sheet constituted with triangular-pyramidal reflective elements whose base planes are present on the same plane is inferior in entrance angularity, that is, every retroreflective sheet has a disadvantage that retroreflective brightness rapidly decreases when the entrance angle of a light to the triangular-pyramidal reflective elements increases.
In general, high brightness, that is, the height (magnitude) and angularity (wide angularity) of a reflection brightness represented by the reflection brightness of the light incoming from the front of a triangular-pyramidal cube-corner retroreflective sheet are required for the sheet as optical characteristics. Moreover, three performances such as observation angularity, entrance angularity, and rotational angularity are requested for the angularity (wide angularity) of the retroreflective sheet.
As described above, every retroreflective sheet constituted with conventionally publicly-known triangular-pyramidal cube-corner retroreflective elements has a low entrance angularity and has no satisfied observation angularity in general. However, the present inventor et al. found through a ray tracing simulation that it is possible to improve the entrance angularity of the retroreflective sheet constituted with the triangular-pyramidal reflective elements by making the depth (h') of a plane (plane c) having one base edge on the base plane (X-X') of the triangular-pyramidal reflective elements from the apexes (H 1 , H 2 ) of the elements {the depth (h') is equal to the height of the apexes (H 1 , H 2 ) from the base plane (X-X')} substantially larger than the depth (h) of a plane (virtual plane Z-Z') including the base edges (z, w) of two planes (plane a, plane b) substantially perpendicularly intersecting the planes c of the triangular-pyramidal reflective elements.
DISCLOSURE OF THE INVENTION
Still more minutely, the present invention is a triangular-pyramidal cube-corner retroreflective sheet in which triangular-pyramidal cube-corner retroreflective elements protruded on one common base plane (X-X') are arranged on the base plane in a close-packed state so as to face each other by sharing one common base edge on the base plane (X-X') with each other, the base plane (X-X') is one common plane including a plurality of the base edges (x, x, . . . ) shared by the triangular-pyramidal retroreflective elements, two these triangular-pyramidal retroreflective elements facing each other form an element pair of substantially same shapes facing each other so as to be respectively substantially symmetric to planes (Y-Y', Y-Y', . . . ) vertical to the base plane including the common base edges (x, x . . . ) on the base plane (X-X'), the triangular-pyramidal retroreflective elements are formed with substantially same pentagonal lateral faces (c 1 , c 2 ) using the common base edges (x, x, . . . ) as one side and substantially same quadrangular lateral faces (a 1 , b 1 ; a 2 , b 2 ) substantially perpendicularly intersecting the face c 1 or c 2 using two upper sides of the face c 1 or c 2 using the apexes (H 1 , H 2 ) of the triangular-pyramidal retroreflective elements as starting points as one side respectively, sharing one of ridge lines of the triangular-pyramidal retroreflective elements and using the ridge line as one side and the height (h') from the apexes (H 1 , H 2 ) of the triangular-pyramidal retroreflective elements up to the base plane (X-X') including the base edges (x, x, . . . ) of the pentagonal lateral faces (c 1 , c 2 ) of the triangular-pyramidal retroreflective elements is substantially larger than the height (h) from the apexes (H 1 , H 2 ) of the triangular-pyramidal retroreflective elements up to a substantially horizontal plane (virtual plane Z-Z') including base edges (z, w) of other lateral faces (a 1 , b 1 ; a 2 , b 2 ) of the triangular-pyramidal retroreflective elements.
A more preferable triangular-pyramidal cube-corner retroreflective sheet of the present invention is characterized in that triangular-pyramidal cube-corner retroreflective elements protruded on one common base plane (X-X') are arranged in a close-packed state so as to face each other by sharing one common base edge on the base plane (X-X'), the base plane (X-X') is a common plane including the base edges (x, x, . . . ) shared by the triangular-pyramidal reflective elements, two these triangular-pyramidal reflective elements facing each other form a pair of substantially-same-shape elements facing each other so as to be respectively substantially symmetric to planes (Y-Y', Y-Y', . . . ) vertical to the base plane including the common base edges (x, x, . . . ) on the base plane (X-X'), lateral faces (c 1 , c 2 ) of the triangular-pyramidal reflective elements using the common base edges (x, x, . . . ) as one side are continuously arranged along the common base edges by respectively forming a substantially same pentagon, two other lateral faces (a 1 , b 1 and a 2 , b 2 ) constituting the triangular-pyramidal reflective elements respectively form a substantially same quadrangular lateral face using the two upper sides of the face c 1 or c 2 using the apexes (H 1 , H 2 ) of the triangular-pyramidal reflective elements as starting points as one side and sharing one of the ridges of the triangular-pyramidal reflective elements and using the ridge as one side, a plane (virtual plane Z-Z') including base edges (z, w) of the lateral faces (a 1 , b 1 ) formed by the fact that the lateral faces (a 1 , b 1 ) of the quadrangle intersect the corresponding quadrangular lateral face (a 2 or b 2 ) of other triangular-pyramidal reflective elements adjacent to the lateral faces (a 1 , b 1 ) is substantially parallel with the base plane (X-X') and located substantially upper than the base plane (X-X'), and the optical axis of the triangular-pyramidal reflective elements forms at least an angle of 3° from the vertical plane (Y-Y') in the direction in which the difference (q-p) between the distance (q) from the intersection between the optical axis of the triangular-pyramidal reflective elements and the base plane (X-X') up to the base edges (x, x, . . . ) shared by the element pair and the distance (p) from the intersection (P) between a perpendicular extended from the apexes (H 1 , H 2 ) of the elements to the base plane (X-X') and the base plane (X-X') up to the base edges (x, x, . . . ) shared by the elements becomes plus.
The present invention is more minutely described below by properly referring to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top view of triangular-pyramidal cube-corner retroreflective elements of the prior art;
FIG. 2 is a sectional view of triangular-pyramidal cube-corner retroreflective elements of the prior art;
FIG. 3 is a top view of triangular-pyramidal cube-corner retroreflective elements for explaining the present invention;
FIG. 4 is a sectional view of triangular-pyramidal cube-corner retroreflective elements for explaining the present invention;
FIG. 5 is an enlarged top view of a pair of triangular-pyramidal reflective elements for explaining the present invention;
FIG. 6 is an enlarged sectional view of a pair of triangular-pyramidal reflective elements for explaining the present invention;
FIG. 7 is a graph showing the relation between optical-axis tilt angle (θ) and brightness observed from the front calculated through ray tracing simulation; and
FIG. 8 is a sectional view showing the structure of one embodiment of a triangular-pyramidal cube-corner reflective sheet of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Before explaining the present invention, a conventional publicly-known art is first described below.
FIGS. 1 and 2 show a top view and a sectional view for explaining triangular-pyramidal cube-corner retroreflective elements of the prior art in order to compare the elements with triangular-pyramidal cube-corner retroreflective elements of the present invention. In FIG. 1, triangular-pyramidal cube-corner retroreflective elements protruded onto a common plane share common base edges (x, x, . . . ) and base planes of the triangular-pyramidal cube-corner retroreflective elements are arranged on one common plane (X-X') in a close-packed state, as a pair of elements facing each other so as to be symmetric to a plane (Y-Y') vertical to the common plane (X-X') including the base edges (x, x, . . . ) shared by the retroreflective elements.
Moreover, FIG. 2 shows a sectional view of the triangular-pyramidal reflective elements, taken along the line (L-L') of the element group shown in FIG. 1. Optical axes of these element pairs arranged on triangular-pyramidal cube-corner retroreflective sheets tilt in the directions opposite to each other. The optical axes tilt from the vertical plane (Y-Y') in the direction in which the difference (q-p) between the distance (p) from the intersection (P) between a perpendicular extended from the apexes (H 1 , H 2 ) of the elements to the base plane (X-X') and the base plane (X-X') up to the base edges (x, x, . . . ) shared by the elements and the distance (q) from the intersection (Q) between an optical axis and the base plane up to the base edges (x, x, . . . ) shared by the elements becomes plus.
FIGS. 3 and 4 show a top view and a sectional view for explaining triangular-pyramidal cube-corner retroreflective elements of the present invention. FIG. 3 shows that the triangular-pyramidal reflective elements of the present invention protruded onto one common base plane (X-X') are arranged in a close-packed state by sharing one of common base edges (x, x, . . . ) on the base plane (X-X') and facing each other. Moreover, FIG. 4 shows a sectional view of triangular-pyramidal reflective elements of the present invention, taken along the line (L-L') of the element group shown in FIG. 3. As shown in FIG. 3, triangular-pyramidal reflective elements of the present invention are formed with pentagonal lateral faces (c 1 , c 2 ) facing each by sharing one base edge (x) on the base plane (X-X') and substantially same quadrangular lateral faces (a 1 , b 1 and a 2 , b 2 ) substantially perpendicularly intersecting the face c 1 or c 2 using two upper sides of the face c 1 or c 2 using the apexes (H 1 , H 2 ) of the triangular-pyramidal reflective elements as starting points as one side respectively and sharing one of the ridge lines of the triangular-pyramidal reflective elements and using the ridge line as one side.
As shown in FIG. 3, triangular-pyramidal reflective elements of the present invention are arranged in a close-packed state in repetitive patterns by forming a pair of elements having the substantially same shape, sharing one base edge (x) on the base plane (X-X'), and facing each other so as to be substantially symmetric. Therefore, the common base edge (x) forms a continuous straight line. Moreover, a plurality of base edges (x) shared by adjacent groups of other triangular-pyramidal reflective pairs are parallel with the straight line constituting the base edge (x) and form a parallel straight line group having equal repetitive pitches.
Therefore, because the lateral faces (c 1 , c 2 ) of triangular-pyramidal reflective elements of the present invention share the base edge (x) and face each other and the base edge (x) forms a continuous straight line, the face c 1 forms a continuous plane and the face c 2 also forms a continuous plane. Moreover, the quadrangular lateral face observed along the line x in FIG. 3 (small quadrangular lateral face between the faces a 1 and b 1 and two faces c 2 )) are also located on the plane on the ling x formed by the face c 1 or c 2 . As a result, the plane formed with the face c 1 or c 2 and the lateral face having the small quadrangle is present on the continuous straight line and forms the same lateral face as the face c forming a groove with a V-shaped cross section.
The term "substantial" in this specification is an expression including even a very small difference. For example, "substantially symmetric" and "substantially same shape" are expressions including a case in which corresponding side and/or angle is and/or are completely the same and the value of the side or angle is different very slightly, for example, by approx. 1% or less of the value.
To make the present invention easily be understood, the enlarged top view of a pair of triangular-pyramidal reflective elements shown as ##STR1## in FIG. 3 is shown as FIG. 5 and the side view viewed from the direction of the arrow shown by the line L-L' in FIG. 3 is shown as FIG. 6.
In FIG. 6, the face c 1 of an element R 1 at the right of a pair of triangular-pyramidal reflective elements of the present invention (that is, the element shown by ##STR2## in FIG. 3) is a pentagonal plane enclosed by points H 1 -D 1 -A-B-E 1 , the face a 1 is a quadrangular plane enclosed by points H 1 -J 1 -F 1 -D 1 , the face b 1 is a quadrangular plane enclosed by points H 1 -J 1 -G 1 -E 1 , the faces a 1 and b 1 have substantially the same shape, and the faces c 1 , a 1 , and b 1 substantially perpendicularly intersect each other. Moreover, the base plane of a right triangular-pyramidal reflective element R 1 shown by a plane A-B-K 1 forms a part of the common base plane (X-X').
In FIG. 6, a left triangular-pyramidal reflective element shown by R 2 corresponds to the left triangular-pyramidal reflective element of the above elements shown by ##STR3## in FIG. 3 and its base plane is shown by A-B-K 2 . The triangular-pyramidal reflective element R 2 whose base plane is shown by A-B-K 2 has the same shape as the right reflective element R 1 whose base plane is shown by A-B-K 1 and the elements R 1 and R 2 are present at the both sides of the base (A-B) (this is present on the common base edges x in FIG. 3) shared by the both elements R 1 and R 2 , and the left element R 2 has a shape obtained by rotating the right element R 1 about the center (O) of the base (A-B) shared by the both elements R 1 and R 2 by 180° on the base plane X-X'.
Therefore, in FIG. 5, the face c 2 shown by the points H 2 -D 2 -B-A-E 2 of the left element R 2 , the face a 2 shown by the points H 2 -J 2 -F 2 -D 2 , and the face b 2 shown by the points H 2 -J 2 -G 2 -E 2 respectively substantially have the same shape as the faces c 1 , a 1 , and b 1 of the right element R 1 and the faces c 2 , a 2 , and b 2 also substantially perpendicularly intersect each other.
Therefore, in FIG. 6 which is a side view viewed from the direction of the line L-L' in FIG. 5, the side view of the right element R 1 shown by the points B-H 1 -J 1 -K 1 and that of the left element R 2 shown by the points B-H 2 -J 2 -K 2 are substantially symmetric to right and left and have the same shape.
As shown in FIG. 6, apexes of the triangular-pyramidal reflective elements (R 1 , R 2 ) of the present invention are shown by H 1 and H 2 and the height of the apexes (H 1 , H 2 ) from the common base plane (X-X') is shown by h'.
As shown in FIGS. 5 and 6, the height h' corresponds to the depth of a V-shaped trough formed by the faces c 1 and c 2 facing each other of the triangular-pyramidal reflective elements R 1 and R 2 of the present invention from a plane (virtual plane) including the apexes H 1 and H 2 of the elements.
Moreover, as clearly understood from FIGS. 5 and 6, the quadrangular lateral faces a 1 , b 1 and a 2 , b 2 of the triangular-pyramidal reflective elements R 1 and R 2 of the present invention substantially have the same shape, base edges F 1 -D 1 and G 1 -E 1 of the lateral faces a 1 and b 1 of the element R 1 and base edges F 2 -D 2 and G 2 -E 2 of the lateral faces a 2 and b 2 of the element R 2 are present on a virtual plane (Z-Z') forming the same plane, and the height from the virtual plane Z-Z' up to a plane (virtual plane) including the apexes H 1 and H 2 of the elements R 1 and R 2 are shown by h in FIG. 6.
Therefore, the depth of troughs for the lateral faces a 1 , b 1 and a 2 , b 2 of the triangular-pyramidal reflective elements R 1 and R 2 of the present invention to respectively form with corresponding lateral faces of other adjacent elements from a plane including the apexes H 1 and H 2 (the bottoms of the troughs are bases of the lateral faces a 1 , b 1 and a 2 , b 2 ) is shown by h.
The triangular-pyramidal reflective elements (R 1 , R 2 , . . . ) of the present invention are characterized in that the depth (h') of the trough formed with the faces c 1 and c 2 is larger than the depth (h) of the troughs formed by the faces a 1 , b 1 and a 2 , b 2 (and planes corresponding to these faces).
Moreover, as shown in FIGS. 3 and 5, base edges of faces a 1 and a 2 of the triangular-pyramidal reflective elements R 1 and R 2 of the present invention are present on a common line w, base edges of the faces b 1 and b 2 are located on a common line z, and base edges of the faces c 1 and c 2 are located on a common line x.
In the case of the present invention, when assuming the height of the apexes (H 1 , H 2 ) of triangular-pyramidal reflective elements of the present invention from the base plane (X-X') as h' and the height of the apexes (H 1 , H 2 ) from the virtual plane (Z-Z') as h, a cube-corner retroreflective sheet whose value of h'/h ranges between 1.05 and 1.5 is preferable, particularly a cube-corner retroreflective sheet whose value of h'/h ranges between 1.07 and 1.4 is preferable.
Moreover, as shown in FIGS. 3 to 6, a plurality of triangular-pyramidal reflective elements of the present invention are arranged on the base plane (X-X') including the common base edges (x, x, . . . ) in a close-packed state by sharing the base edges (x, x, . . . ) shared by two corresponding faces c of the triangular-pyramidal reflective elements and facing each other as already described.
The present invention is described below by referring to FIGS. 3 to 6. That is, a cube-corner retroreflective sheet is preferable which is characterized in that triangular-pyramidal cube-corner retroreflective elements protruded onto one common base plane (X-X') are arranged on the base plane (X-X') in a close-packed state by sharing one common base edge on the base plane (X-X') and facing each other, the base plane (X-X') is one common plane including a plurality of base edges (x, x, . . . ) shared by the triangular-pyramidal reflective elements, two these triangular-pyramidal reflective elements facing each other form a pair of substantially-same-shape elements facing each other so as to be respectively substantially symmetric to planes (Y-Y', Y-Y', . . . ) vertical to the base plane (X-X') including the common base edges (x, x, . . . ) on the base plane (X-X'), lateral faces (c 1 , c 2 ) using the base edges (x, x, . . . ) shared by the triangular-pyramidal reflective elements as one side form substantially same pentagons and are continuously arranged along the common base edges, two other lateral faces (a 1 , b 1 and a 2 , b 2 ) forming the triangular-pyramidal reflective elements form substantially same quadrangular lateral faces by using two upper sides of the face c 1 of c 2 using the apexes (H 1 , H 2 ) of the triangular-pyramidal reflective elements as starting points and sharing one of the ridge lines of the triangular-pyramidal reflective elements and using the ridge line as one side, a plane (virtual plane Z-Z') including base edges (z, w) of the lateral faces (a 1 , b 1 ) formed by the fact that the quadrangular lateral faces (a 1 , b 1 ) intersect the quadrangular lateral face (a 2 or b 2 ) corresponding to other triangular-pyramidal reflective elements adjacent to the lateral faces (a 1 and b 1 ) is substantially parallel with the base plane (X-X') and located substantially upper than the base plane (X-X') of the triangular-pyramidal reflective elements, and the optical axis of the triangular-pyramidal reflective elements tilts by an angle (θ) of at least 3° from the vertical plane (Y-Y') in a direction in which the difference (q-p) between the distance (q) from the intersection (Q) between the optical axis of the triangular-pyramidal reflective elements and the base plane (X-X') up to the base edges (x, x, . . . ) shared by the element pair and the distance (p) from the intersection (P) between a perpendicular extended from the apexes (H, H 2 ) of the triangular-pyramidal reflective elements to the base plane (X-X') and the base plane (X-X') up to the base edges (x, x, . . . ) shared by the element pair becomes plus.
Moreover, the present invention is described below by referring to FIG. 6. That is, an angle (θ) formed between an optical axis passing through the apex H 1 of the triangular-pyramidal reflective element R 1 and a perpendicular (H 1 -P) extended from the apex H 1 to the base plane (X-X') {this can be also considered as the plane (Y-Y') vertical to the base plane (X-X')} is referred to as optical-axis tilt angle and it is preferable to set an optical-axis tilt angle (θ) to at least 3° in a direction in which the difference (q-p) becomes plus.
Furthermore, in the case of the present invention, a cube-corner retroreflective sheet is preferable in which the optical axis of the triangular-pyramidal reflective elements tilts by 4° to 12° from the plane (Y-Y') in a direction in which the difference (q-p) between the distance (p) from the intersection (P) between a perpendicular extended from the apexes (H 1 , H 2 ) of the triangular-pyramidal reflective elements to the base plane (X-X') and the intersection (P) up to the base edges (x, x, . . . ) shared by the element pair and the distance (q) from the intersection (Q) between the optical axis of the triangular-pyramidal reflective elements and the base plane (X-X') up to the base edges (x, x, . . . ) shared by the element pair becomes plus, particularly a cube-corner reflective sheet is preferable in which the optical axis tilts by 5° to 10° from the vertical plane (Y-Y') in a direction in which the difference (q-p) becomes plus.
Furthermore, in the case of the present invention, a cube-corner retroreflective sheet is preferable which has triangular-pyramidal reflective elements in which the distance (h) from a plane (virtual plane Z-Z') including a plurality of base edges (z, w) of lateral faces (a 1 , b 1 or a 2 , b 2 ) formed by the fact that substantially same quadrangular lateral faces (a 1 , b 1 ) sharing one ridge line using the apex of a plurality of triangular-pyramidal cube-corner retroreflective elements protruded onto a common base plane (X-X') as a starting point and using the ridge line as one side intersect corresponding quadrangular lateral faces (a 2 or b 2 ) of other triangular-pyramidal reflective element adjacent to the lateral faces (a 1 , b 1 ) up to the apexes (H 1 , H 2 ) of the triangular-pyramidal reflective elements ranges 50 μm and 400 μm, particularly between 60 μm and 200 μm, more particularly between 70 μm and 10 μm.
Because the height (h') from the apexes (H 1 , H 2 ) of triangular-pyramidal reflective elements of the present invention up to the common base plane (X-X') is substantially larger than the height (h) from the apexes (H 1 , H 2 ) of the triangular-pyramidal reflective elements up to the virtual plane (Z-Z'), various improvements of optical characteristics are obtained.
These improvements can be achieved because h' is substantially larger than h and thereby, the area of the face c 1 can be increased compared to the lateral face of c 1 of the prior art. Particularly, the light incoming at an angle almost vertically to the face c 1 , in other words, in the case of a large entrance angle, the entrance angularity is remarkably improved because the area of the face c 1 is increased.
Moreover, the above improvements of the optical characteristics by increase of the area of the face c 1 are particularly remarkable in the case of a triangular-pyramidal reflective element having a tilted optical axis, particularly when the optical axis of the triangular-pyramidal reflective element tilts in a direction in which the difference (q-p) between the distance (p) and the distance (q) becomes plus.
In the case of the present invention, when an optical axis tilts so that the difference (q-p) becomes plus, the entrance angularity is particularly improved. In the case of a triangular-pyramidal reflective element having a tilted optical axis according to the prior art, however, there is a disadvantage that areas of the lateral faces (c 1 , c 2 ) having the common base edge (x) become smaller than those of the lateral faces (c 1 , c 2 ) before tilted because a normal triangular-pyramidal reflective element whose optical axis is not tilted tilts the optical axis so that the difference (q-p) becomes plus and thus, the probability of retroreflection due to trihedral reflection decreases. For the incoming light to reflect on three lateral faces and efficiently retro-reflect, it is preferable that the areas of three lateral faces are equal. In the case of a triangular-pyramidal reflective element with a tilted optical axis according to the prior art, however, the probability of retroreflection due to trihedral reflection is decreased because areas of the lateral faces (c 1 , c 2 ) having a common base decrease compared to two other faces (a 1 , b 1 and a 2 , b 2 ) as a tilt angle increases. Therefore, the retroreflective performance (front reflection brightness) of the light incoming from the front is deteriorated and moreover, the retroreflective performance (entrance angularity) when a tilt angle increases is deteriorated.
When an optical axis tilts so that (q-p) becomes plus, areas of the lateral faces (c 1 , c 2 ) of a triangular-pyramidal reflective element decrease to approx. 91% when the optical-axis tilt angle (θ) is +3°, approx. 86% when the angle (θ) is +4°, and approx. 62% when the angle (θ) is +12° compared to areas before the optical axis tilts and thereby, the front reflection brightness and entrance angularity are deteriorated.
It is possible to confirm the deterioration of the front brightness due to decrease of the area ratio through geometric ray-tracing computer simulation. FIG. 7 shows the front brightness of a triangular-pyramidal reflective element of the prior art calculated by assuming the entrance angle as 0° and the observation angle as 0° when keeping the height (h) at 80 μm and changing optical-axis tilt angles (θ) from 0° to +14°. Thus, it is found that the front brightness deteriorates as the tilt angle (θ) increases.
In the case of a triangular-pyramidal reflective element of the present invention, however, it is possible to make areas of the lateral faces (c 1 , c 2 ) larger than the lateral faces of a triangular-pyramidal reflective element formed by the prior art because the height (h') from the apexes (H 1 , H 2 ) up to the common base (X-X') is designed so as to be substantially larger than the height (h) from the apexes (H 1 , H 2 ) up to the virtual plane (Z-Z').
Therefore, in the case of a triangular-pyramidal reflective element of the present invention, it is possible to improve the disadvantage that the brightness is deteriorated due to decrease of the area of the face c of the triangular-pyramidal reflective element by tilting an optical-axis up to +3° or more in a direction in which (q-p) becomes plus. In the case of the present invention, it is preferable that an optical axis tilts so that the optical-axis tilt angle (θ) ranges between +4° and +12°, particularly between +5° and +10°. A triangular-pyramidal reflective element having an optical-axis tilt angle (θ) exceeding 12° is not preferable because the element is excessively deformed, the reflection brightness greatly depends on an angle at which light enters the element (that is, rotation angle), and thus the rotation angularity deteriorates.
In the case of a triangular-pyramidal reflective element, an optimum optical characteristic is obtained when the value of h'/h ranges between 1.05 and 1.5, more preferably ranges between 1.07 and 1.4. Because areas of the lateral faces (c 1 , c 2 ) sharing the base of a triangular-pyramidal reflective element meeting the above values of h'/h can have almost equal areas for areas of two other lateral faces (a 1 , b 1 , and a 2 b 2 ), it is possible to increase light which are retroreflected due to trihedral reflection.
Because three lateral faces (a 1 , b 1 , c 1 ) of a triangular-pyramidal reflective element of the present invention is not greatly changed in the area ratio viewed from the front or the area ratio viewed from the entrance axis direction, the triangular-pyramidal reflective element is improved in both front brightness characteristic and entrance angularity.
Moreover, when the value of h'/h is equal to or less than 1.0, particularly when the value is less than 1.05, increase rates of the areas of the faces c 1 and c 2 are not very remarkable. However, when the value of h'/h exceeds 1.4, the ratio between the areas of two other lateral faces (a 1 , b 1 and a 2 , b 2 ) decreases compared to the areas of the lateral faces (c 1 , c 2 ) sharing a base, it is difficult to improve optical characteristics because of the reason same as the above.
It is preferable that the height (h) from the apexes (H 1 , H 2 ) of a triangular-pyramidal reflective element of the present invention up to the virtual plane (Z-Z') of the triangular-pyramidal reflective element ranges between 50 and 400 μm and it is more preferable that the height (h) ranges between 60 and 200 μm. When the height (h) is less than 50 μm, the size of the element is extremely decreased. Therefore, dispersion of retroreflective light becomes excessive due to the diffraction effect determined by the base-plane opening area of the element and thus, the front brightness characteristic is deteriorated. Moreover, the height (h) exceeding 400 μm is not preferable because the thickness of a sheet is extremely increased and a soft sheet is not easily obtained.
Moreover, three prism face angles formed when three lateral faces (a 1 , b 1 , c 1 ) or (a 2 , b 2 , c 2 ) serving as prismatic faces of a triangular-pyramidal reflective element of the present invention intersect each other substantially form right angles. However, it is not always necessary to form a strict right angle (90°). It is also possible to provide a very small angle deviation for the prism face angles. By providing a very slight angle deviation for the prism face angles, it is possible to properly disperse the light reflected from an obtained triangular-pyramidal reflective element. However, when excessively increasing the angle deviation, the retroreflective performance is deteriorated because the light reflected from the obtained triangular-pyramidal reflective element is excessively dispersed. Therefore, it is preferable to keep at least one prism face angle formed when these three lateral faces (a 1 , b 1 , c 1 ) or (a 2 , b 2 , c 2 ) intersect each other between 89.5° and 90.5° in general or preferably between 89.7° and 90.3°.
A triangular-pyramidal cube-corner retroreflective sheet of the present invention can be generally manufactured by using a cube-corner forming mold in which shapes of the above-described triangular-pyramidal reflective elements are arranged in a close-packed state on a metallic belt as reversed concave shapes, hot-pressing a proper soft resin sheet superior in optical transparency and uniformity against the forming mold, and reversing the shape of the mold and transferring the reversed shape to the resin sheet.
A typical method for manufacturing the above cube-corner forming mold is described in, for example, Stamm's U.S. Pat. No. 3,712,706 in detail. Also in the case of the present invention, it is possible to use a method according to the above method.
Specifically, for example, a microprism master block in which convex very-small triangular pyramids are arranged in a close-packed state by cutting parallel grooves whose groove depths (h) are equal and whose sectional form are V-shaped on a base material with a flatly-ground surface by using a super-hard tool (e.g. diamond-tipped tool or tool made of tungsten carbide) with a point angle of 73.4 to 81.0° and thereby, determining a repetitive pitch, groove depth (h), and mutual crossing angle in each of two directions (z-direction and w-direction in FIG. 3) correspondingly to the shape of a purposed triangular-pyramidal reflective element and then, using a similar super-hard tool with a point angle of 64.5 to 46.5° and thereby, cutting V-shaped parallel grooves on the base material in a third direction (x-direction) at a repetitive pitch (repetitive pitch of the line x in FIG. 3) passing through the intersection between the formed x- and w-directional grooves so as to divide the supplementary angle of the crossing angle between these two directions (in this case, the acute angle is referred to as the crossing angle) into two equal angles. In this case, in the case of the present invention, the x-directional groove depth (h') is made larger than the w-directional groove depth (h).
In the case of a preferred mode of the present invention, the z- and w-directional repetitive pitches range between 100 and 810 μm, the groove depth (h) ranges between 50 and 400 μm, the mutual crossing angle ranges between 43 and 55°, and the x-directional depth (h') ranges between 75 and 600 μm.
In general, these x-, w-, and z-directional grooves are cut so that the cross section of each groove becomes a isosceles triangle. However, it is also possible to cut these three-directional grooves so that the cross section of at least one of these directional grooves is slightly shifted from the isosceles triangle. As specific methods for cutting the grooves, it is possible to list a method of cutting the grooves by a tool whose front-end shape is asymmetric to right and left and a method of cutting the grooves by slightly tilting a tool symmetric to right and left. Thus, by slightly shifting the cross section of a groove from an isosceles triangle, it is possible to provide a very-slight angle deviation from a right angle (90°) for at least one of the prism face angles of three lateral faces (a 1 , b 1 , c 1 ) or (a 2 , b 2 , c 2 ) of an obtained triangular-pyramidal reflective element and thereby, it is possible to properly disperse the light reflected from the triangular-pyramidal reflective element from a complete retroreflective direction.
It is preferable to use a metal having a Vickers hardness (JIS Z 2244) of 350 or more, particularly 380 or more as the base material preferably usable for fabrication of the microprism master block. Specifically, it is possible to use one of amorphous copper, electrolysis nickel, and aluminum. As an alloy-based material, it is possible to use one of copper-zinc alloy (brass), copper-tin-zinc alloy, nickel-cobalt alloy, nickel-zinc alloy, and aluminum alloy.
Moreover, it is possible to use a synthetic resin as the base material. However, it is necessary to avoid using a synthetic resin which causes a trouble that the resin cannot be accurately cut because it is softened under cutting. Therefore, it is preferable to use a material made of a resin having a glass transition point of 150° C. or higher, particularly having a glass transition point of 200° C. or higher and a Rockwell hardness (JIS Z 2245) of 70 or more, particularly 75 or more. Specifically, it is possible to use one of a polyethylene-terephthalate-based resin, polyethylene-phthalate-based resin, polycarbonate-based resin, polymethly-methacrylate-based resin, polyimide-based resin, polyarylate-based resin, polyether-sulfone-based resin, polyether-imide-based resin, and cellulose-triacetate-based resin.
A flat plate can be formed with one of the above synthetic resins by a normal resin forming method such as an extrusion forming method, calendar forming method, or solution casting method and moreover, it is possible to perform treatments such as heating and extending according to necessity. It is possible to apply a preliminary conducting treatment to the plane of the flat plate thus formed in order to simplify the conducting treatment and/or electroforming treatment when making an electroformed mold from the prism master block manufactured by the above method. As the preliminary conducting treatment, it is possible to use the vacuum deposition method for vacuum-depositing metals such as gold, silver, copper, aluminum, zinc, chromium, nickel, and selenium, cathode sputtering method using these metals, or electroless plating method. Moreover, it is possible to provide the conductivity for the flat plate by blending the conductive powder of carbon black or the like or organic metallic salt with a synthetic resin.
Then, electroforming is applied to the surface of the obtained microprism master block and a metallic film is formed on the surface. By removing the metallic film from the surface of the master block, it is possible to make a metallic mold for forming a triangular-pyramidal corner-cube retroreflective sheet of the present invention.
When using a metallic microprism master block, it is possible to clean the surface of the die according to necessity and thereafter, immediately apply the electroforming to the surface. However, when using a synthetic-resin microprism master block, it is necessary to apply the conducting treatment for providing conductivity for the prism surface of a master block before applying the electroforming to the surface. As the conducting treatment, it is possible to use one of the silver mirror treatment, electroless plating treatment, vacuum deposition treatment, and cathode sputtering treatment.
As the silver mirror treatment, it is specifically possible to use a method of cleaning the surface of the master block formed by the above method with an alkaline detergent to remove dirt such as oil component from the surface, thereafter activating the surface with a surface active agent such as tannic acid, and quickly transforming the surface into a silver mirror by using a silver nitrate solution. The sliver-mirror transformation can use the spraying method using a double-cylinder nozzle for a silver nitrate solution and a reducing-agent (e.g. glucose or glyoxal) solution or the soaking method for soaking a master block in a mixed solution of a silver nitrate solution and a reducing agent solution. Moreover, it is preferable that the thickness of a silver mirror film is as thin as possible as long as the conductivity under electroforming is kept and therefore, for example, a thickness of 0.1 μm or less is preferable.
Electroless plating uses copper and nickel. An electroless nickel plating solution can use nickel sulfate or nickel chloride as a water-soluble metallic salt of nickel. A plating solution is obtained by adding a solution mainly containing citrate or malate to the solution as a complexing agent and moreover adding sodium hypophosphite, sodium hydrogen boride, or amine borane to the solution as a reducing agent.
The vacuum deposition treatment can be performed by cleaning the surface of a master block and then putting the master block in a vacuum device, heating and vaporizing a metal such as gold, silver, copper, aluminum, zinc, nickel, chromium, or selenium, precipitating the metal on the cooled mother-die surface, and forming a conductive film on the surface, similarly to the case of the silver mirror treatment. Moreover, the cathode sputtering treatment can be performed by putting a master block treated similarly to the case of the vacuum deposition treatment in a vacuum device in which a flat cathode plate for mounting a desired metallic foil on it and a metallic anode table made of aluminum or iron for mounting a material to be treated on it and putting the master block on the anode table, setting a metallic foil same as the foil used for the vacuum deposition to a cathode, electrifying the foil to cause glow discharge, making a cation flow generated by the glow discharge collide with the metallic foil on the cathode and thereby evaporating metallic atoms or particulates, and precipitating the atoms or particulates on the mother-die surface and forming a conductive film on the surface. It is preferable that a conductive film formed by one of these methods has a thickness of 300 Å.
To form a smooth and uniform electroformed film on a prism master block made of a synthetic resin, it is necessary to uniformly apply the conducting treatment to the entire surface of the master block. When the conducting treatment is ununiformly applied, a trouble may occur that the smoothness of the surface of an electroformed layer at a portion with inferior conductivity deteriorates or no electroformed layer is formed but a defective portion is formed.
To avoid the above trouble, it is possible to use a method of improving the wetting of a silver mirror solution by treating a treatment surface with a solvent such as alcohol immediately before starting the silver mirror treatment. However, because a prism master block made of a synthetic resin formed for the present invention has a very-deep acute-angle concave portion, wetting is not completely improved. The trouble of a conductive film due to the concave shape also easily occurs in the vacuum deposition treatment.
To uniform the surface of an electroformed layer obtained through electroforming, activation treatment is frequently performed. As the activation treatment, it is possible to use a method of soaking the electroformed layer in a sulfamic acid solution of 10 wt %.
When electroforming a master block made of a synthetic resin to which the silver mirror treatment is applied, a sliver layer is integrated with an electroformed layer and easily removed from the synthetic-resin master block. However, when forming a conductive film of nickel through the electroless-plating or cathode-sputtering treatment, it may be difficult to separate an electroformed layer after electroforming from a synthetic-resin layer because the synthetic-resin surface well adheres to the conductive film. To avoid the above trouble, it is necessary to apply the so-called separation treatment such as chromate treatment to the surface of the conductive film layer before starting electroforming. In this case, the conductive film layer remains on the synthetic-resin layer after separation.
The synthetic-resin prism master block with a conductive film layer formed on it undergoes the above various pre-treatments and thereafter, an electroformed layer is formed on the conductive film layer through electroforming. In the case of a prism master block made of a metal, the surface is cleaned and then, an electroformed layer is formed directly on the metal.
Electroforming is generally performed in an aqueous solution of 60 wt % of sulfamic acid at a temperature of 40° C. and a current of approx. 10 A/dm 2 . A uniform electroformed layer is easily obtained by setting an electroformed-layer forming rate to, for example, 48 hr/mm or less. At a forming rate of higher than 48 hr/mm, a trouble easily occurs that the surface smoothness is lost or a defective portion occurs in the electroformed layer.
Moreover, it is possible to perform nickel-cobalt-alloy electroforming in which a component such as cobalt is added to the alloy in order to improve the frictional characteristic of the surface of a mold. By adding 10 to 15 wt % of cobalt, it is possible to harden the Vickers hardness Hv of an obtained electroformed layer up to 300 to 400. Therefore, to manufacture a triangular-pyramidal cube-corner retroreflective sheet of the present invention by using an obtained electroformed mold and thereby forming a synthetic resin, it is possible to improve the durability of the mold.
Thus, a first-generation electroformed mold formed from a prism master block can be repeatedly used as an electroformed master used to further form a second-generation electroformed mold. Therefore, it is possible to form a plurality of electroformed molds from one prism master block.
The electroformed master blocks thus formed are accurately cut and then, they can be used by combining and joining them up to a final mold size for forming a microprism sheet made of a synthetic resin. To join the master blocks, it is possible to use a method of making cut ends butt each other or a method of welding a combined joined portion by, for example, electron beam welding, YAG laser welding, or CO 2 laser welding.
The combined electroformed mold is used to form a synthetic resin as a synthetic-resin forming mold. As the synthetic resin forming method, it is possible to use compression molding or injection molding.
The compression molding can be performed by inserting a formed thin-wall nickel electroformed mold, a synthetic resin sheet having a predetermined thickness, and a silicone-rubber sheet having a thickness of approx. 5 mm as a cushion material into a compression molding press heated up to a predetermined temperature and then, preheating them for 30 sec at a pressure of 10 to 20% of a forming pressure and heating and pressurizing them for approx. 2 min at a temperature of 180 to 250° C. and a pressure of 10 to 30 kg/cm . Thereafter, by cooling them up to room temperature while keeping them pressurized and releasing the pressure, it is possible to obtain a molded prism.
Moreover, it is possible to obtain a continuous sheet-like product by joining thin-wall electroformed molds having a thickness of approx. 0.5 mm formed by the above method to form an endless belt mold, setting the belt mold onto a pair of rollers comprising a heating roller and a cooling roller to rotate it, supplying a melted synthetic resin to the belt mold present on the heating roller in the form of a sheet to pressure-form the melted synthetic resin with one silicone roller or more, thereafter cooling the resin up to the glass transition temperature or lower on the cooling roller, and separating it from the belt mold.
Then, a mode of the structure of a cube-corner retroreflective sheet of the present invention is described below by referring to FIG. 8 showing a sectional view of the structure.
In FIG. 8, symbol 1 denotes a reflective element layer on which triangular-pyramidal reflective elements (R 1 , R 2 ) of the present invention are arranged in a close-packed state, 2 denotes a holding body layer for holding reflective elements, and 10 denotes a light entrance direction. The reflective element layer (1) and the holding body layer (2) are normally united into one body. However, it is also possible to form the layers by superimposing separate layers each other. In accordance with a purpose and an operating environment of a retroreflective sheet of the present invention, it is possible to use a surface protective layer (4), a printing layer (5) for communicating information to an observer or coloring a sheet, a binder layer (6) for realizing an airtight structure for preventing moisture from entering the back of a reflective element layer, a support layer (7) for supporting the binder layer (6), and an adhesive layer (8) and a separating material layer (9) used to attach the retroreflective sheet to other structure.
It is possible to use the resin same as that used for the retroreflective element layer (1) for the surface protective layer (4). Moreover, to improve the weather resistance, it is possible to use an ultraviolet absorbent, light stabilizer, and oxidation inhibitor independently or by combining them. Moreover, it is possible to make the resin contain various organic pigments, inorganic pigments, and dyes serving as coloring agents.
It is possible to normally set the printing layer (5) between the surface protective layer (4) and the holding body layer (2) or on the surface protective layer (4) or the reflection surface of the reflective element (1) by such means as gravure, screen printing, or ink-jet printing.
Though a material constituting the reflective element layer (1) and the holding body layer (2) is not restricted as long as the material meets flexibility which is one of the objects of the present invention, it is preferable to use a material having optical transparency and uniformity. The following resins can be listed as materials usable for the present invention: polycarbonate resin, vinyl chloride resin, (meth)acrylic resin, epoxy resin, polystyrene resin, polyester resin, fluorocarbon resin, polyolefin resin such as polyethylene resin or polypropylene resin, cellulose resin, and polyurethane resin.
In the case of the reflective element layer (1) of the present invention, it is general to set an air layer (3) to the back of a cube-corner retroreflective element in order to increase a critical angle meeting an internal total reflective condition. To prevent a trouble such as decrease of a critical angle due to entrance of moisture or corrosion of a metallic layer under an operating condition, it is preferable that the reflective element layer (1) and the support layer (7) are sealed by the binder layer (6). As the method for sealing the layers, it is possible to use the methods disclosed in U.S. Pat. Nos. 3,190,178 and 4,025,159 and Japanese Utility Model Laid-Open No. Sho 50-28669. The binder layer (6) can use any one of (meth)acrylic resin, polyester resin, alkyd resin, and epoxy resin. As the joining method, it is possible to properly use any one of the publicly-known thermally-fusible-resin joining method, thermosetting-resin joining method, ultraviolet-curing-resin joining method, and electron-beam-curing-resin joining method.
It is possible to apply the binder layer (6) used for the present invention to the entire surface of the support layer (7) or selectively set the layer (6) to the joint with a retroreflective element layer by a method such as the printing method. As a material for forming the support layer (7), it is possible to use a resin for forming a retroreflective element layer, a general resin capable of forming a film, fiber, cloth, and a metallic foil or plate of stainless steel or aluminum independently or by combining them.
For the adhesive layer (8) used to attach a retroreflective sheet of the present invention to a metallic plate, wooden plate, glass plate, or plastic plate and the separation layer (9) for the adhesive, it is possible to properly select publicly-known materials.
EMBODIMENTS
The present invention is further specifically described below in accordance with embodiments.
Embodiment 1
Parallel grooves having a V-shaped sectional form are cut on a brass plate of 100-mm square with a flatly-ground surface in the first direction (z direction in FIG. 3) and the section direction (w direction in FIG. 3) at a repetitive pattern through the fly cutting method by using a diamond-tipped tool having a point angle of 77.89° so that the repetitive pitch in z and w directions becomes 163.64 μm, the groove depth (h) becomes 80 μm, and the crossing angle between lines z and w shown by ∠A-K 1 -B in FIG. 5 becomes 49.22°.
Thereafter, a master block in which a plurality of convex triangular-pyramidal cube corners with a height (h) of 80 μm from the virtual plane (Z-Z') of a triangular-pyramidal reflective element are arranged in a close-packed state is formed on a brass plate by using a diamond-tipped tool with a point angle of 54.53° and thereby cutting V-shaped parallel grooves in the third direction (x direction) so that the repetitive pitch (repetitive pitch of the line x in FIG. 3) becomes 196.46 μm, the groove depth (h') becomes 90 μm, and the crossing angle between the third direction and the first direction and that between the third direction and second direction become 65.39° respectively. The optical-axis tilt angle θ of the triangular-pyramidal reflective elements is +8° and each of prism face angles of three faces forming a triangular pyramid is 90°. Moreover, h'/h is 90/80=1.125.
A concave cube-corner forming mold made of nickel and having a reversed shape is formed by the brass master block through the electroforming method. By using the forming mold, a polycarbonate-resin triangular-pyramidal cube-corner retroreflective sheet in which cube corners in which a support layer has a thickness of approx. 250 μm, h=80 μm and h'=90 μm, and prism face angles of three faces forming a triangular pyramid do not have any angle deviation are arranged in a close-packed state is formed on the surface of a polycarbonate-resin sheet having a thickness of 300 μm {"YUPIRON (transliterated) E2000" made by MISTUSBISHI ENGINEERING PLASTICS (transliterated) Co., Ltd.} by compression-molding the polycarbonate sheet at a molding temperature of 200° C. and a molding pressure of 50 kg/cm 2 and thereafter, cooling the sheet up to 30° C. while pressurized and taking out the sheet.
Embodiment 2
A groove having a V-shaped sectional form is cut on a brass plate of 100-mm square with a flatly-ground surface through the fly cutting method by using a diamond-tipped tool whose point angle is 77.81° in the first direction (z direction) and the second direction (w direction) and 54.45° in the third direction (x direction) so that the repetitive pitch in the first and second directions becomes 163.64 μm, the depth (h) of a cut groove becomes 80 μm, the crossing angle between the first and second directions becomes 49.22° and moreover, the repetitive pitch in the third direction becomes 196.46 μm and the depth (h') of a cut groove becomes 90 μm to form a master block in which a plurality of convex triangular-pyramidal cube corners in which the height (h) of a triangular-pyramidal reflective element from the virtual plane (Z-Z') is 80 μm are arranged on the brass plate in a close-packed state. The optical-axis tilt angle θ of the triangular-pyramidal reflective element is 8° and each of the prism face angles of three faces forming a triangular pyramid is 89.92°. Moreover, h'/h is 90/80=1.125.
Moreover, similarly to the case of the embodiment 1, a cube-corner forming mold made of nickel is formed to form a polycarbonate triangular-pyramidal cube-corner retroreflective sheet in which cube corners in which the thickness of a support layer is approx. 250 μm, h=80 μm and h'=90 μm, and prism face angles of three faces forming a triangular pyramid have a very small angle deviation are arranged in a close-packed state on the surface of a polycarbonate resin sheet same as that of the embodiment 1 by compression-molding the sheet under the same conditions as the case of the embodiment 1.
Comparative Example 1
A groove with a V-shaped sectional form was cut on a brass plate of 100-mm square with a flatly-ground surface at a repetitive pattern through the fly cutting method so that the repetitive pitch in the first direction (z direction) and the second direction (w direction) becomes 181.24 μm and the repetitive pitch in the third direction (x direction) becomes 160.29 μm, and the crossing angle between the first and second directions becomes 68.86° by using a diamond-tipped tool whose point angle is 61.98° in the first and second directions and 86.53° in the third direction to form a master block in which a plurality of convex triangular-pyramidal cube corners with a cube-corner retroreflective element having a height of 80 μm are arranged on the brass plate in a close-packed state. The optical-axis tilt angle θ of the reflective element was -8° and each of the prism face angles of three faces forming a triangular pyramid was 90°.
A polycarbonate-resin triangular-pyramidal cube-corner retroreflective sheet was formed through the same method as the case of the embodiment 1.
Comparative Example 2
A groove with a V-shaped sectional form was cut on a brass plate of 100-mm square with a flatly-ground surface at a repetitive pattern through the fly cutting method so that the repetitive pitch in the first direction (z direction) and the second direction (w direction) becomes 166.92 μm and the repetitive pitch in the third direction (x direction) becomes 177.23 μm, and the crossing angle between the first and second directions becomes 56.18° by using a diamond-tipped tool whose point angle is 77.34° in the first and second directions and 64.53° in the third direction to form a master block in which a plurality of convex triangular-pyramidal cube corners with a reflective element having a height of 80 μm are arranged on the brass plate in a close-packed state. The optical-axis tilt angle θ of the reflective element was +3° and each of the prism face angles of three faces forming a triangular pyramid was 90°.
A polycarbonate-resin triangular-pyramidal cube-corner retroreflective sheet was formed through the same method as the case of the embodiment 1.
Table 1 shows measured data for retroreflection brightnesses of the triangular-pyramidal cube-corner retroreflective sheets formed for the above embodiments 1 and 2 and comparative examples 1 and 2 {the unit of each reflection brightness is (cd/Lx*m 2 )}. The retroreflective sheets of the embodiment 1 and comparative example 2 respectively show a high reflection brightness in a wide range. However, the reflective sheet of the comparative example 1 has a large brightness change particularly at an entrance angle of 5° to 10° and the reflective sheet of the comparative example 2 has a large brightness drop at an entrance angle of 30°. Therefore, any comparative example is inferior to the embodiments in entrance angularity.
TABLE 1______________________________________Entrance Observationangle Embod- Comparative Comparative(Degree) (Degree) iment 1 iment 2 example 1 example 2______________________________________5 0.2 890 830 770 869 18510 800 16430 440 134______________________________________ | The present invention relates to a triangular-pyramidal cube-corner retroreflective sheet constituted with triangular-pyramidal cube-corner retroreflective elements useful for signs including traffic signs and construction work signs, license plates of automobiles and motorcycles, safety materials of clothing and life preservers, markings of signboards, and reflectors of visible-light, laser-beam, and infrared-ray reflective sensors, in which a lateral face (c) using one of the base edge (x) of triangular-pyramidal reflective elements arranged in a close-packed state on a base plane (X-X') and facing each other by sharing the base edge (x) on the base plane (X-X') as one side is pentagonal, other faces (a, b) sharing one of ridge lines starting with apex (H) of the triangular-pyramidal reflective elements are quadrangular, and the height (h) from the apex (H) up to the base plane (X-X') is substantially larger than the height (h') from the apex (H) up to a substantially horizontal plane (virtual plane Z-Z') including the base edges (z, w) of other lateral faces (a, b) of the triangular-pyramidal reflective elements.
CROSS-REFERENCE TO RELATED APPLICATION | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. patent application Ser. No. 11/342,749 filed on Jan. 30, 2006, now U.S. Pat. No. 7,824,559; which application claims the benefit under 35 USC 120 of the filing dates of U.S. Provisional Application No. 60/651,050, filed on Feb. 7, 2005, U.S. Provisional Application No. 60/654,718, filed on Feb. 17, 2005, and U.S. Provisional Application No. 60/723,312, filed on Oct. 4, 2005. The entire disclosures of the above applications are incorporated herein by reference.
FIELD OF THE INVENTION
This invention relates to a device and method for preparing platelet-plasma concentrates with improved wound healing properties for use as a tissue sealant and adhesive. The product has a fully active (un-denatured) fibrinogen concentration that is several times greater than the concentration of fibrinogen in blood and a platelet concentration that is greater than the concentration of platelets in blood.
BACKGROUND OF THE INVENTION
Blood can be fractionated, and the different fractions of the blood are useful for different medical needs. Under the influence of gravity or centrifugal force, blood spontaneously separates into three layers. At equilibrium, the top low-density layer is a straw-colored clear fluid called plasma. Plasma is a water solution of salts, metabolites, peptides, and many proteins ranging from small (insulin) to very large molecules (complement components).
The bottom, high-density layer is a deep red viscous fluid comprising anuclear red blood cells (erythrocytes) specialized for oxygen transport. The red color is imparted by a high concentration of chelated iron or heme that is responsible for the erythrocytes' high specific gravity. The relative volume of whole blood that consists of erythrocytes is called the hematocrit, and in normal human beings this can range from about 37% to about 52% of whole blood.
The intermediate layer is the smallest, appearing as a thin white band above the erythrocyte layer and below the plasma layer; this is called the buffy coat. The buffy coat itself has two major components, nucleated leukocytes (white blood cells) and anuclear smaller bodies called platelets (or thrombocytes). Leukocytes confer immunity and contribute to debris scavenging. Platelets seal ruptures in blood vessels to stop bleeding, and deliver growth and wound healing factors to a wound site. Slower speed centrifugation or shorter duration centrifugation permits separation of erythrocytes and leukocytes from plasma, while the smaller platelets remain suspended in the plasma, resulting in platelet rich plasma (PRP).
U.S. Pat. No. 5,585,007 identifies methods for making plasma concentrates from whole blood for use in wound healing and as a tissue sealant. This patent is hereby incorporated by reference in its entirety. This device, designed for placement in a medical laboratory or surgical amphitheatre, uses a disposable cartridge for preparing tissue sealant. The device was particularly applicable for stat preparations of autologous tissue sealants. Preparation in the operating room of 5 ml of sealant from 50 ml of patient blood required less than 15 minutes and only one simple operator step. There was no risk of tracking error because preparation could take place in the operating room during the surgical procedure. Chemicals added could be limited to anticoagulant (e.g., citrate) and calcium chloride. The disposable cartridge could fit in the palm of the hand and was hermetically sealed to eliminate possible exposure to patient blood and to ensure sterility. Adhesive and tensile strengths of the product were comparable or superior to pooled blood fibrin sealants made by precipitation methods. Use of antifibrinolytic agents (such as aprotinin) was not necessary because the tissue sealant contained high concentrations of natural inhibitors of fibrinolysis from the patient's blood.
This device used a new sterile disposable cartridge with the separation chambers for each run. Since the device was designed to be used in a normal medical setting with ample power, the permanent components were designed for long-term durability, safety and reliability, and were relatively heavy, using conventional centrifuge motors and accessories.
Small, self-contained centrifugal devices for obtaining platelet concentrates from blood are described in commonly assigned, copending application Ser. No. 10/394,828 filed Mar. 21, 2003, the entire contents of which are hereby incorporated by reference. This device separates blood into erythrocyte, plasma and platelet layers and selectively removes the platelet layer as a platelet concentrate, that is, platelets suspended in a minimal amount of plasma. The plasma fraction, being in an unconcentrated form, is not effective as a hemostat or tissue adhesive.
Platelet rich plasma is a concentrated platelet product that can be produced from whole blood through commercially available systems, resulting in varying levels of platelet concentration. Platelets play a crucial role in the signaling cascade of normal wound healing. Activated platelets release the contents of their α-granules resulting in a deposition of powerful growth factors such as platelet derived growth factor (PDGF), transforming growth factor β-(TGF-β), vascular endothelial growth factor (VEGF), and epidermal growth factor (EGF). PRP has been used in many different clinical applications, demonstrating the effectiveness and importance of the product for a variety of medical procedures. For example, percutaneous application of PRP to patients with severe lateral epicondylitis, or tennis elbow, resulted in improved elbow function and reduced pain. Early maturation of bony fusion was observed when platelet concentrate was used during lumbar spinal fusions. Chronic diabetic foot ulcers treated with PRP achieved increased healing rates compared to the control group receiving standard care. Studies by Bhanot el at show decreased formation of hematoma and seroma, decreased postoperative swelling, and improved healing time for plastic surgeries that included PRP in the treatment. Further, during dental surgeries, the use of PRP has improved bone regeneration around implants.
PRPs have demonstrated numerous clinical benefits to patients. There are many devices on the market that concentrate platelets to differing levels. At this time, it is unclear the amount of platelets that is most efficient for each surgical application. Concentrations of at least 1,000×10 3 platelets/μL are recommended. The system described in copending application Ser. No. 10/394,828 can provide platelets up to 8 time baseline concentration, and the normal human platelet range is 200×10 3 platelets/μL to 400×10 3 platelets/μL. This means a highly effective concentrate in a range of 1,600×10 3 platelets/μL to 3,200×10 3 platelets/μL.
However, the PRP products of the prior invention, while achieving greatly increased platelet concentrations, did not have tissue sealant and hemostatic properties needed for many surgeries. The platelet-free plasma concentrates, while they were excellent sealants and hemostats, did not provide the healing properties of platelets.
SUMMARY OF THE INVENTION
It is therefore an objective of the present invention to provide an apparatus and method for preparing a novel PRP concentrate that combines enhanced platelet levels in concentrated plasma, in which the fibrinogen levels have not been significantly denatured.
The device of this invention is a PRP separator-concentrator comprising a housing, a PRP separation assembly, and a PRP concentration assembly. The concentration assembly has a PRP concentration sump. An axially concentric rigid stationary outlet tube is secured to the housing and extends through the PRP separation assembly to the PRP concentrate sump. The PRP separation assembly is attached to and positioned above the PRP concentration assembly to form a combined separator-concentrator assemblage that is rotatable about the outlet tube.
The PRP separation assembly can comprise a separation chamber having an outer wall with an inner wall surface and a sloped floor secured to the outer wall, the inner wall surface being lined with a depth filter having pores and passageways that are sized to receive and entrap erythrocytes during centrifuging. The PRP separation assembly includes a blood inlet.
The separation chamber can include a top plate and a balanced distribution of separator plates attached to the outer wall and floor of the separation chamber, the separator plates lying in a plane that is parallel to the central axis. The separator plates can extend from the outer wall radially inward to a distance beyond the surface of the depth filter and from the floor to a position spaced from the top plate. The separation chamber is balanced for substantially vibration-free rotation about the central axis.
The PRP concentrator can comprise a concentration chamber having a floor for supporting desiccated beads and a wall with at least one opening closed with a screen. The screen has openings that are sized to retain the desiccated beads in the concentration chamber. The concentration chamber can be surrounded by an outer wall with a sloped floor secured thereto, the sloped floor including at its center, a PRP concentrate sump. The concentrator can have a distribution of upright screen supports, the upright screen supports having an inner surface and an outer surface, the cylindrical screen being supported on the outer surface of the upright screen supports.
A stationary bead rake can be secured to the stationary tube and extend outward therefrom, the rake having distal ends that are spaced at a distance from the upright screen supports. The rake can comprise a longitudinal body, the center of which is secured to the rigid outlet tube. The longitudinal body can optionally have weakened fracture points adjacent to the rigid tube, whereby the longitudinal body fractures when it is exposed to excessive strain from swelled bead contact during high speed centrifugation.
The concentration assembly can have secured to its bottom, an axially concentric concentrator drive coupling, the PRP separator-concentrator including a motor assembly with a motor coupling that engages the concentrator drive coupling. The motor assembly can comprise a motor control system for timed rotations of the drive coupling during an acceleration phase, a rapid centrifugal erythrocyte separation phase, a deceleration phase, a slow stir concentrating phase, an acceleration phase, and a rapid centrifugal PRP concentrate separation phase.
The PRP separator-concentrator of this invention can include a valve assembly and a central passageway connecting the separation chamber and the concentration chamber, the upper surface of the central passageway including a valve seat. The valve seat includes a valve face that forms a seal with the valve seat in the close position and separates to disengage the seal in the open position. The valve assembly can include a pair of opposed normally upright valve operator arms, each operator arm having an inflexible body with a weighted distal end and a flexible proximal end. Each flexible proximal end can be secured to the valve face at a level that elevates the valve face in an axial direction to move the valve face to the open position when the operator arms pivot outward under centrifugal force during fast rotation of the separator-concentrator about its central axis. The flexible proximal ends can be positioned between opposed plates extending upward from the floor of the separation assembly, each plate having plate side edges, the plate side edges being positioned to contact the operator arms and thereby restrain the proximal ends against rotation around the central axis when the arms are in the upright position and to free the operator arms from rotation when the flexible proximal ends are raised above the plate side edges when the valve is opened. The plates can have a top edge that is positioned to support the operator arms after their axial rotation, thereby preventing their return to the upright position when centrifugal rotation is ended, thereby preventing closure of the valve assembly.
The method of this invention for preparing PRP concentrate comprises the steps of preparing PRP from patient blood by capturing patient blood erythrocytes in a depth filter and preparing PRP concentrate by absorbing water in the PRP with absorbent beads. The method includes capturing the erythrocytes by rotating blood at centrifugal speeds in a balanced cylindrical separation chamber that is lined with the depth filter, the separation chamber and depth filter being segmented by radially extending plates into separation zones, the plates maintaining substantially balanced distribution of the blood in the separation zones during rotation of the separation chamber, thereby reducing vibration and erythrocyte displacement from the depth filter.
In this method, the rotational speed of the separation chamber can be accelerated to centrifugal speeds at a rate that allows balanced distribution of blood in the separation zones, and after the centrifuging is complete, the rotation speed of the separation chamber can be decelerated to below centrifugal speeds at a rate that allows balanced distribution of the PRP in the separation zones, thereby reducing vibration and erythrocyte displacement from the depth filter. The PRP can be contacted in a rotating concentrating chamber with desiccated beads to produce PRP concentrate while the beads are stirred with a stationary rake. The PRP concentrate can be collected by rotating the concentration chamber at centrifugal speeds to separate PRP concentrate from the beads.
The method for preparing PRP concentrate can comprise the steps of preparing PRP from patient blood by capturing patient blood erythrocytes in a depth filter, and preparing PRP concentrate by absorbing water in the PRP with absorbent beads. PRP concentrate can be produced by contacting PRP with desiccated beads in a rotating concentrating chamber while the beads are stirred with a stationary rake. The PRP concentrate can be collected by rotating the concentration chamber at centrifugal speeds to separate PRP concentrate from the beads.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of a disposable separation and concentration assembly and a permanent drive assembly, with desiccated beads shown in only half of the concentration subassembly.
FIG. 2 is a front view of the outer housing of the separation-concentration assembly of this invention.
FIG. 3 is a perspective view of the outer housing of FIG. 2 showing details of the motor assembly connector.
FIG. 4 is a cross-sectional drawing of the separation-concentration sub-assemblies shown in FIG. 1 .
FIG. 5 is a top view of the outer cap subassembly of the separation-concentration assembly shown in FIG. 4 .
FIG. 6 is a cross-sectional view of the outer cap subassembly shown in FIG. 5 , taken along the line 6 - 6 .
FIG. 7 is an exploded, isometric view of the outer cap subassembly shown in FIG. 5 .
FIG. 8 is a top view of the top bucket cap subassembly of the separation-concentration assembly shown in FIG. 4 .
FIG. 9 is a cross-sectional view of the top bucket cap subassembly shown in FIG. 8 , taken along the line 9 - 9 .
FIG. 10 is an exploded view of the sample inlet subassembly.
FIG. 11 is a top view of the top bucket subassembly of the separation-concentration assembly shown in FIG. 4 .
FIG. 12 is a cross-sectional view of the top bucket subassembly of FIG. 11 , taken along the line 12 - 12 .
FIG. 13 is a front view of the valve assembly of the separation-concentration assembly shown in FIG. 4 .
FIG. 14 is an exploded, isometric view of the valve assembly of FIG. 13 .
FIG. 15 is a cross-sectional view of the bottom bucket subassembly shown in FIG. 4 , taken along the central axis.
FIG. 16 is an enlarged cross-sectional view of the motor drive connector shown in FIG. 15 .
FIG. 17 is a front view of the basket subassembly of the separation-concentration assembly shown in FIG. 4 .
FIG. 18 is a cross-sectional view of the basket subassembly of FIG. 16 , taken along the line 18 - 18 .
FIG. 19 is a top view of the mixer assembly of the separation-concentration assembly shown in FIG. 4 .
FIG. 20 is a cross-sectional view of the mixer assembly of FIG. 19 , taken along the line 20 - 20 .
FIG. 21 is an isometric view of the mixer assembly of FIGS. 19 and 20 .
FIG. 22 is a perspective view of the motor drive assembly of this invention.
FIG. 23 is a cross-sectional view of the motor drive assembly of FIG. 22 taken along the line 23 - 23 .
FIG. 24 is a cross-sectional view of the motor drive assembly of FIG. 22 taken along the line 24 - 24 .
FIG. 25 is a cross-sectional view of the upper bucket and valve assembly of FIG. 4 , taken along the central axis.
FIG. 26 is a cross-sectional view of the upper bucket and valve assembly of FIG. 21 , taken along the line 26 - 26 .
FIG. 27 is a cross-sectional view of the upper bucket and valve assembly of FIG. 4 , after the centrifugal action of the spinning upper bucket has extended the arms of the valve assembly and opened the valve.
FIG. 28 is a cross-sectional view of the view of upper bucket and valve assembly of FIG. 27 , taken along the line 28 - 28 .
FIG. 29 is a cross-sectional view of the upper bucket and valve assembly of FIG. 27 , after rotational displacement of the arms of the valve assembly.
FIG. 30 is a cross-sectional view of the upper bucket and valve assembly of FIG. 29 , taken along the line 30 - 30 .
FIG. 31 is a cross-sectional view of the upper bucket and valve assembly of FIG. 29 , after centrifugal separation has been completed.
FIG. 32 is a cross-sectional view of the separation and concentration assembly of FIG. 1 , after blood has been introduced into the separation chamber.
FIG. 33 is a cross-sectional view of the separation and concentration assembly of FIG. 32 as erythrocytes are separated from the plasma-platelet mixture during high speed centrifugation.
FIG. 34 is cross-sectional view of the separation and concentration assembly of FIG. 33 , after platelet-plasma fraction has passed into the concentration chamber.
FIG. 35 is a cross-sectional view of the separation and concentration assembly of FIG. 34 at the beginning of the high speed centrifugation to separate the platelet-plasma concentrate from the hydrogel bead.
FIG. 36 is a cross a cross-sectional view of the separation and concentration assembly of FIG. 35 after platelet-plasma concentrate has collected in the platelet-plasma concentrate sump.
DETAILED DESCRIPTION OF THE INVENTION
The apparatus and method of this invention prepares a novel PRP concentrate that combines enhanced platelet levels in a plasma concentrate in which the fibrinogen levels have not been significantly denatured. The novel product combines the sealant and haemostatic properties of the plasma concentrates greatly valued in certain types of surgery with the enhanced healing properties provided by elevated platelet levels.
FIG. 1 is a cross-sectional view of a disposable separation and concentration assembly and a permanent drive assembly, with desiccated beads shown in half of the concentration subassembly. Details of the sub-sections of this assembly are hereinafter described in conjunction with more detailed drawings.
The upper housing 2 is described in greater detail hereinbelow in conjunction with FIGS. 2 and 3 .
The motor drive subsystem 4 is described together with the motor drive system in conjunction with FIGS. 22-24 .
The separation system 3 enclosed in the upper housing 2 is described in greater detail with regard to FIG. 4 . The separation system comprises a combination of subsystems including the outer cap subassembly 6 described in greater detail with respect to FIGS. 5-7 ; a top bucket 8 described in greater detail with regard to FIGS. 8 and 9 ; a sample inlet subassembly shown in FIG. 10 ; a top bucket cap subassembly 10 described in greater detail with respect to FIGS. 11 and 12 ; and a valve subassembly 12 described in greater detail with respect to FIGS. 13 and 14 .
The concentrating system 11 includes a lower bucket 14 and drive connector 16 , described in greater detail with regard to FIGS. 15 and 26 ; a basket subassembly 18 described in greater detail with regard to FIGS. 17 and 18 ; and a mixer assembly described in greater detail with regard to FIGS. 19 to 21 .
FIG. 2 is a front view of the outer housing of the separation-concentration assembly of this invention, and FIG. 3 is a perspective view of the outer housing of FIG. 2 showing details of the motor assembly connector.
The upper housing 2 isolates the sterile separation and concentration systems shown in FIG. 1 . The upper portion of the outer housing 2 is sealed with an outer cap subassembly 34 having a blood inlet tube 86 and a PRP concentrate outlet port 62 and cap 66 . Referring to FIG. 3 , the lower assembly connector has a drive recess 42 shaped to engage the motor subassembly, and with spacer receptors 44 for holding spacers 46 . The outer housing 2 and its enclosed separation components are a disposable unit to be used with a permanent drive assembly shown in FIGS. 1 and 22 to 24 . The lower assembly includes an axially concentric motor drive receptor 48 and a plurality of tapered engagement and locking slots 50 that engage with corresponding mounting projections of the motor drive assembly (not shown).
FIG. 4 is a cross-sectional drawing of the separation-concentration sub-assemblies shown in FIG. 1 . The outer housing 2 encloses an upper separation subassembly 3 and a lower concentration subassembly 11 .
The top of the outer housing 2 is closed with outer cap subassembly 6 shown in greater detail with regard to FIGS. 5-7 . The outer cap subassembly 6 comprises a circular cap 56 with an annular flange 58 extending downward for securing it to the top of the upper housing 2 . Concentrate outlet conduit 60 passes through an outlet conduit hole 62 in the center of the plate 56 , extending through the plate and communicating with the separation chamber 64 ( FIG. 4 ). Circular cap 66 has a central receptor 68 that engages with a Luer fitting 70 on the upper end of the outlet conduit 60 to maintain a sterile closure during the separation process.
An inlet port hole 72 is positioned in the circular cap 56 , spaced from the central axis. The inlet port hole 72 is sized to engage the exterior inlet conduit 74 shown in FIG. 4 .
The Luer fitting 70 is provided to engage an empty applicator syringe for removing platelet rich plasma concentrate product according to this invention. The lower end of the concentrate outlet conduit 60 constitutes a receptor for receiving the upper end of rigid tube 74 ( FIG. 4 ).
The bucket cap 10 shown in FIG. 4 is described in greater detail with regard to FIGS. 8 and 9 . FIG. 8 is a top view of the top bucket cap subassembly 10 of the separation-concentration assembly shown in FIG. 4 , and FIG. 9 is a cross-sectional view of the top bucket cap subassembly shown in FIG. 10 , taken along the line 9 - 9 . The cap subassembly 10 closes the top separation bucket 8 shown in greater detail with respect to FIGS. 11 and 12 . The top bucket cap 10 comprises a circular plate 76 with a connecting flange 78 that extends downward from the lower edge of plate 76 . While the upper plate 6 is fixed to the outer housing 2 ( FIG. 4 ) and is stationary during the separation and concentration processes, top bucket cap 10 is secured to the top bucket 8 for rotation with the top bucket 8 during the separation and concentration processes.
The circular cap 10 has an axially concentric hole with a valve assembly guide tube 80 extending downwardly therefrom. The lower end of the guide tube 80 has a valve assembly stop flange 82 secured thereto. The upper end of the guide tube 80 supports sleeve bearing 84 .
The circular cap 10 has a sample inlet subassembly 86 that aligns with the hole 72 in the circular cap 56 ( FIG. 5 ).
FIG. 10 is an exploded view of the sample inlet subassembly 86 . The sample inlet subassembly 86 comprises an inlet tube 92 mounted in the plate 76 , the top of the inlet tube 92 including an annular receptor 94 . A sterile filter 96 is positioned in the lower end of the passageway 97 of tube 92 .
The subassembly 86 includes a removable inlet tube 98 . Inlet tube 98 comprises a central tube 100 having at its upper end an integral Luer fitting 102 . At an intermediate level of the tube 100 , an annular plate 103 extends outward from the tube. An integral cylindrical flange 104 extends downward from the outer edge of the plate 103 . The flange 104 is sized to engage the receptor 94 . The lower end 105 of the tube 100 is sized to engage the upper end of the passageway 97 .
The inlet tube is provided with a cap 106 that engages the Luer fitting 102 to provide a sterile closure of the removable inlet tube 98 during shipment and handling prior to use.
The inlet tube 98 in passing through the hole 72 in the stationary circular cap 56 locks the separation and concentration subassemblies against rotation during shipment and storage. After the patient blood is introduced into the top bucket 8 ( FIG. 4 ) through the inlet subassembly 86 , the inlet tube 98 is removed, unlocking the separation and concentration sub-assemblies 3 and 11 from the stationary circular cap 6 , freeing them for rotation about the central tube 74 .
A sterile breathing tube 108 is secured to the circular plate 76 to permit air flow from the separation chamber 64 when blood is introduced and to permit air movement into the system when platelet-rich concentrate is removed from the concentrating system 11 , as described in greater detail hereinafter. Sterile air filter 110 in breathing tube 108 ( FIG. 9 ) prevents entrance of micro-organisms into the interior of the separation chamber, preserving sterility.
The top bucket subassembly in FIG. 4 is shown in detail in FIGS. 11 and 12 . FIG. 11 is a top view of the top bucket subassembly 10 of the separation-concentration assembly shown in FIG. 4 , and FIG. 12 is a cross-sectional view of the top bucket subassembly of FIG. 11 , taken along the line 12 - 12 . The top bucket subassembly 10 comprises a cylindrical outer wall 112 having a top edge 114 that is secured to the inner surface of the flange 58 of the upper bucket cap 10 . The lower end of the cylindrical outer wall 112 is closed with integral sloped floor plate 116 with a central passageway 118 that constitutes a central flow passageway for separated platelet-plasma. The inner wall surface of the passageway 118 constitutes a valve seat 119 for the valve assembly described in greater detail hereinafter with respect to FIGS. 13 and 14 . Spaced from the central passageway 118 and secured to the floor plate 116 are vent columns 120 with filters 122 in their bottom. The columns 120 serve as vents allowing movement of air from the concentration subassembly into the separation chamber when liquid flows through downward through the central passage 118 , as is explained hereinafter. Filters 122 prevent escape of hydrogel beads from the basket subassembly 18 through the vent columns 120 during transport or handling of the device of this invention. Surrounding the central passageway 118 and secured to the upper surface of the tapered floor plate 116 are upwardly extending abutment plates 124 , each having an upper valve arm abutment surface 128 .
A plurality of radially inwardly extending separation plates 130 are secured to the inner surface of the cylindrical outer wall 112 and the sloped floor plate 116 . Each adjacent pair of these plates defines a separation zone 132 . The plates 130 must be evenly spaced around the cylindrical outer wall to provide a balanced subassembly. They can be in matched, opposed pairs, for example the three matched sets as shown in FIG. 11 . The top edge 134 of each of the separation plates 130 is spaced at a distance below the top edge 114 to permit overflow of blood in order to achieve an even distribution of blood between each the separation zones 132 during the spin acceleration stages and during the spin deacceleration stages, thus maintaining balance and minimizing vibration of the rotating assembly.
The interior surface 136 of the cylindrical outer wall segments in each of the each separation zones 132 is lined with an open-cell foam segment or depth filter segment 138 . The foam segments 138 have pores and passageways sized to allow infiltration of erythrocytes into the foam and subsequent entrapment of erythrocytes during the high speed centrifugation of the separation stage. The pores and passageways are sized to retain entrapped erythrocytes thereafter when the spinning slows or stops and the erythrocyte-free platelet-plasma suspension flows downward through the opening 118 .
FIG. 13 is a front view of the valve assembly 12 of the separation-concentration assembly shown in FIG. 4 , and FIG. 14 is an exploded, isometric view of the valve assembly of FIG. 13 . The valve assembly 12 comprises a central tube 140 , the lower end constituting a valve face 142 . The valve face 142 comprises an annular receptor 144 that receives and holds an O-ring 146 . The outermost surface of the O-ring 146 is sized to form a sealing engagement with the valve seat 119 (See FIGS. 11 and 12 ).
The valve assembly 12 includes two opposed centrifugal arms 148 secured to the tube 140 above the valve face 142 . Each centrifugal arm 148 has a flexible portion 150 adjacent the tube 140 and a rigid arm portion 152 . The distal end of the rigid arm portion 152 includes a weight receptor 154 in which a weight 156 is secured to provide additional weight to the end of the rigid arm portion. Operation of the valve assembly is described hereinafter with respect to FIGS. 25-31 .
The lower bucket 14 in FIG. 4 is shown in detail in FIGS. 15 and 16 . Referring to FIG. 15 , the lower bucket 14 has a cylindrical sidewall 158 and a sloped bucket bottom 160 , the lower portion of which forms a platelet-plasma concentrate sump 162 in which concentrated platelet and plasma concentrate collects. A plurality of basket supports 164 extend upward from the top surface of the slopped bucket bottom 160 , the top surfaces 166 of which support a concentrating basket subassembly 18 described hereinafter with regard to FIGS. 17 and 18 .
An axially concentric drive receptor 168 shown in detail in FIG. 16 is secured to the bottom surface of the slopped bucket bottom 160 . The drive connector receptor 168 can have any configuration that will releasably couple with a suitably configured motor drive connector. In the configuration shown in FIGS. 15 and 16 , the drive receptor 168 comprises an outer cylinder 170 and a plurality of ridges 172 , each ridge having a tapered leading engagement surface 174 , an abutment surface 176 and an upper plate 178 . The upper plate 178 transmits the torque from the drive motor (described hereinafter with respect to FIGS. 22-24 ) to the lower bucket bottom 160 and from there to the concentrating and separating subassemblies, all of which are secured together to form a unitary rotatable assembly.
FIG. 17 is a front view of the basket subassembly 18 of the separation-concentration assembly shown in FIG. 4 , and FIG. 18 is a cross-sectional view of the basket subassembly of FIG. 17 , taken along the line 18 - 18 . The basket subassembly 18 comprises a cylinder 180 secured to a circular floor plate 182 . A slip bearing 184 is positioned in the axial center of the circular plate 182 for engaging the rigid tube 74 ( FIG. 4 ). The cylinder 180 has an array of windows 186 around its circumference, each window closed with a fine screen 188 having a mesh size sufficiently small to prevent escape of hydrogel beads 19 ( FIGS. 1 and 4 ) from the basket during spinning.
FIG. 19 is a top view of the mixer assembly of the separation-concentration assembly shown in FIG. 4 . FIG. 20 is a cross-sectional view of the mixer assembly of FIG. 18 , taken along the line 20 - 20 , and FIG. 21 is an isometric view of the mixer assembly of FIGS. 19 and 20 . The mixer assembly 20 comprises a rake 190 secured to stationary tube 74 . The upper end 192 of the stationary tube 74 is secured to the upper cap subassembly 34 to secure it against rotation. The lower end 194 of the stationary tube 74 is an inlet port for removal of platelet-plasma concentrate from the sump 162 ( FIG. 15 ). The rake 190 comprises a radially extending spine 196 from which integral rake elements 198 extend downward to an elevation short of the bottom plate 182 of the basket subassembly 18 as shown in FIGS. 4 , 17 and 18 . The spine 196 can have optional breakaway notches 200 adjacent its center. The notches 200 weaken the spine and direct fracture of the spine 196 at the location of the notches if the event that the pressure produced by contact by beads 19 with the rake elements 198 during the final centrifugal spin become excessive.
The stationary tube 74 extends through the sleeve bearing 184 of the basket subassembly 18 and through the sleeve bearing 84 of the top bucket cap, permitting free rotation of the separating and concentrating assemblies around the stationary tube. The stationary tube 74 is fixed to the outer cap subassembly 6 and the stationary outer housing 2 .
FIG. 4 is a comprehensive assemblage of the components shown in FIGS. 5-20 .
Concentrating desiccated hydrogel beads 19 fill the lower half of the basket 18 (only one side is shown empty to enable unobstructed viewing of the windows 186 and screen 188 elements ( FIGS. 17 and 18 ).
The concentrating desiccated hydrogel beads 19 can be insoluble beads or disks that will absorb a substantial volume of water and low molecular weight solutes while excluding high molecular weight solutes and particulates and will not introduce undesirable contaminants into the plasma. They can be dextranomer or acrylamide beads that are commercially available (Debrisan from Pharmacia and BIO-GEL P™ from Bio-Rad Laboratories, respectively). Alternatively, other concentrators can be used, such as SEPHADEX™ moisture or water absorbents (available from Pharmacia), silica gel, zeolites, cross-linked agarose, etc., in the form of insoluble inert beads.
FIG. 4 in conjunction with subassembly FIGS. 5-21 shows the assembly prior to use with the valve assembly 12 secured for shipment by the sleeve 80 into which the valve assembly tube 140 extends and the abutment flange 82 secured to the bottom of the sleeve 80 . The valve face 142 is shown in position against the seat 119 . This confines the beads to the basket 18 and prevents escape of beads into the upper separation chamber 64 if the device is inverted or shaken during transport or handling.
The assembly is secured against rotation around the rigid tube 74 by the position of the removable inlet tube 98 in the hole 72 of the stationary outer cap subassembly 6 .
The upper edge of the cylinder 180 of the basket assembly 18 is secured against the lower surface of the tapered bottom 116 , and the lower surface of the plate 182 is secured against the upper edge surfaces 166 ( FIG. 15 ) of the supports 164 .
Thus assembled, the upper separation subassembly 3 and the lower concentration subassembly 11 rotate as a single unit around the fixed tube 74 . The upper separation subassembly is positioned on the central tube 74 by the slip bearing 84 through which the fixed tube 74 extends. The lower separation subassembly is positioned on the central tube 74 by the slip bearing 184 through which the fixed tube extends. The rake assembly 20 including the tube 74 remain stationary during rotation of the separation and concentration subassemblies 3 and 11 in the separation and concentration phases, to be described in greater detail hereinafter.
FIG. 22 is a perspective view of the motor drive assembly of this invention. FIG. 23 is a cross-sectional view of the motor drive assembly taken along the line 23 - 23 , and FIG. 24 is a cross-sectional view of the motor drive assembly taken along the line 24 - 24 .
The outer shell 202 of the motor housing 4 encloses the motor 218 and supports the control interface 204 and the power connector 206 . The separation-concentrating assemblies are supported on the raised annular support surface 208 surrounding the motor connector 210 . Motor connector 210 has a configuration that will releasably engage the drive receptor 168 ( FIG. 16 ). The bottom of the housing 22 is closed by support plate 212 . A control and power plate 214 for the system is supported by four support struts 216 attached to the underside of the housing shell 202 . Plate 214 is a conventional printed circuit or equivalent board with the electronic components of the control and power system for the device, and in its center, a support 217 for the motor 218 . The electrical components are connected to the control interface 204 and power connector 206 by conventional wiring circuits (not shown). Four support feet 220 are secured to the bottom of the support plate 212 and provide friction surfaces 222 to secure the device on a laboratory surface.
FIGS. 25-31 illustrate the operation of the valve subassembly during and immediately after the initial separation process. Blood and blood products are omitted from these cross-sectional views to allow an unobstructed view of the valve assembly elements at each stage.
FIG. 25 is a cross-sectional view of the upper bucket and valve subassembly of FIG. 4 , taken along the central axis, and FIG. 26 is a cross-sectional view of the upper bucket and valve assembly of FIG. 25 , taken along the line 26 - 26 . This is the view when blood is initially introduced into the top bucket 8 . The arms 148 of the valve subassembly are in their initial upright position, with the central tube 140 positioned in the guide tube 80 and the upper end of each arm contacting the flange 82 . The valve face 142 is in position in the valve seat 119 ( FIG. 12 ) at the upper end of the central passageway 118 , closing the passageway and preventing escape of blood. The flexible portions 150 of the arms 148 are positioned in the channels between the abutment plates 124 and 126 , preventing rotation of the arms 148 about tube 74 during shipment and handling.
FIG. 27 is a cross-sectional view of the upper bucket and valve assembly of FIGS. 25 and 26 , after the centrifugal action of the spinning upper bucket has extended the arms of the valve assembly and opened the valve, and FIG. 28 is a cross-sectional view of the view of upper bucket and valve assembly of FIG. 27 , taken along the line 28 - 28 . After the desired volume of patient blood has been introduced into the top bucket 8 , the separation and concentration assembly is rotated around the tube 74 at a high speed, the centrifugal force created by this rotation causing the blood to flow outward and be distributed evenly by the separation plates into the separation zones 132 . The centrifugal force pools the blood against the outer surface of the foam segments 138 where the more dense erythrocytes preferentially move into the foam, leaving behind erythrocyte-free plasma containing the less dense platelets.
Under the force of centrifugation, the valve arms 148 rotate outward until they contact the sloped floor 116 . This action slides the valve central tube 140 upward to the upper portion of the guide cylinder 180 , pulling the valve face 142 from the central passageway 118 and out of contact with the valve seat 119 to open the passageway 118 . As the arms 148 rotate outward and the valve face 142 is lifted, the lower flexible ends 150 of the arms 148 are also pivoted upward from between the abutment plates 124 and 126 , freeing the arms for rotation about the tube 74 . Because the liquid is held against the foam segments 138 by centrifugal force, it does not flow through the open passageway 118 .
FIG. 29 is a cross-sectional view of the upper bucket and valve assembly of FIGS. 27 and 28 , after rotational displacement of the arms of the valve assembly, and FIG. 30 is a cross-sectional view of the valve structure of FIG. 29 , taken along the line 30 - 30 . When the arms 148 are lifted from between the abutment plates and are freed from constraint by the abutment plates 124 , rotational motion causes the arms 148 to rotate about the rigid tube 74 . The rotation continues until one of the arms 148 contacts an adjacent separation plate 130 in its rotational path. This rotational displacement aligns the lower flexible ends 150 of the arms 148 above a portion of an abutment surface 128 of an abutment plate 124 .
FIG. 31 is a cross-sectional view of the upper bucket and valve assembly of FIGS. 29 and 30 , after centrifugal separation has been completed and the rotation of the separation and concentration subassemblies is slowed or stopped. Under the force of gravity, the platelet-plasma mixture flows to the bottom of the tapered floor 116 , down its sloped surface to the central passageway 118 , and through the central passageway 118 to the basket subassembly 18 for concentration. The removal of the strong centrifugal action may permit the arms 148 to spring upward, causing the valve face 142 to move downward toward the central passageway 118 . This movement is stopped when one or both flexible arm portions 150 contact an opposed abutment surface 128 , leaving the central passageway open to the flow of the platelet-plasma mixture.
The operation of the device of this invention including the separation phase and concentrating phase are described hereinafter in conjunction with FIGS. 32-36 .
FIG. 32 is a cross-sectional view of the separation and concentration assemblies of FIG. 4 , after blood 202 has been introduced into the separation assembly 3 through the tube 110 from a syringe secured to the Luer fitting 102 . The upper tube 100 with the Luer fitting is then removed, unlocking the separation and concentration assemblies 3 and 11 for rotation. The blood flows into the bottom of the top bucket 8 . Air displaced by the incoming liquid escapes through breathing tube 108 . The valve face 142 is in a closed position, preventing escape of the blood from the bucket 8 . The operation of the system is then initiated, and the motor 218 spins the separation and concentration assemblies together around the rigid tube 74 .
FIG. 33 is a cross-sectional view of the separation and concentration assemblies of FIG. 32 as erythrocytes are separated from the plasma-platelet mixture during high speed centrifugation. As the separation and concentration assemblies turn at a high speed, the blood is forced against the foam 138 . The erythrocytes, being more dense than other blood components, preferentially migrate into the pores and passageways of the foam. The valve subassembly opens the valve 142 as the centrifugal forces pivot the outer ends of the arms 148 away from the center, raising the valve face 142 face from valve seat 119 in the central passageway 118 . However, as long as the high speed centrifugation continues, all of the liquid is maintained against the foam. The centrifugal forces also force the hydrogel beads 19 radially outward against the outer screens 188 of the basket subassembly, out of contact with elements of the rake 190 . Centrifugation is continued until a majority of the erythrocytes a completely trapped in the foam. Because any erythrocytes weaken the gel product formed when the product of this invention is applied, the removal of a maximum proportion of the erythrocytes is desired. The speed of centrifugation tends to separate erythrocytes from platelets, leaving a substantial portion of the platelets in the plasma while entrapping a majority of the erythrocytes in the foam.
FIG. 34 is a cross-sectional view of the separation and concentration assembly of FIG. 33 . After the spinning is slowed or stopped, the platelet-plasma fraction 204 flows to the bottom of the upper bucket 8 and down through the central passageway 118 into the basket subassembly 18 where it comes into contact with the desiccated hydrogel beads 19 . These beads concentrate the plasma by absorbing water from the liquid. The separation and concentrating assemblies are then rotated at a slow speed by the motor 218 , stirring the beads by moving them through the stationary spines 196 of the rake 190 . Agitating the beads insures maximum contact of the beads surfaces with the plasma and reduces gel polarization that arises when the plasma thickens adjacent the bead surfaces. This phase is continued until the desired proportion of the water has been removed and the desired concentration of the plasma has been achieved.
FIG. 35 is a cross-sectional view of the separation and concentration assembly of FIG. 34 at the beginning of high speed centrifugation separation of the platelet-plasma concentrate from the hydrogel beads. At this stage, removal and maximum recovery of the platelet rich plasma concentrate 206 from the beads 19 is obtained. The separation and concentration assemblies are rapidly rotated by the motor 218 around the stationary tube 74 , creating centrifugal forces that force the platelet rich plasma concentrate and the beads 19 against the screen elements 188 of the basket 18 . The screen elements prevent escape of the beads 19 as the continuing centrifugal force causes the platelet enriched plasma concentrate to flow from the beads and through the screen. This high speed centrifugation is continued until a maximum recovery of the platelet rich plasma is obtained.
The absorption of water by the hydrogel beads is accompanied by an increase in bead diameter, increasing the bead volume. If the increased bead volume causes the ends of the rake 190 to drag on beads packed on the screen surface, the rake breaks along the break-away notches 200 ( FIG. 19 ), and the rake fragments become mixed with the beads.
FIG. 36 is a cross a cross-sectional view of the separation and concentration assembly of FIG. 35 after the high speed centrifugation has ended and the platelet-plasma concentrate has flowed into the platelet-plasma concentrate sump 162 . The cap 66 has been removed, exposing Luer fitting 70 at the upper end of the tube 60 . An applicator syringe (not shown) is secured to the Luer fitting 70 . The platelet-rich plasma concentrate is removed from the sump 162 by retracting the barrel of the applicator syringe, drawing platelet rich plasma concentrate up through the tubes 74 and 60 and into the syringe. Breathing tube 108 permits air to flow into the system to replace the volume of liquid removed by the syringe, thus preventing the creation of a partial vacuum in the system that would impede liquid removal.
Regarding the concentration factor, for maximum wound-healing, the platelet level is maximized and high concentrate ion factors are sought. For homeostasis, plasma concentrations of 3 to 4 fold over anti-coagulated plasma levels are most effective. Concentrations below 3 fold have an insufficient fibrinogen concentrate ion. Concentrations higher than 4 old have excessive levels of total protein (principally albumin) which interferes with the fibrin gel structure. To obtain a preparation that maximizes haemostatic effectiveness while also providing improved (albeit perhaps less than maximal) wound-healing potential, a concentration range of 3 to 4 fold over anti-coagulated plasma levels is a best choice. For applications where sealant activity is not desired, high concentrations may be preferred.
Regarding erythrocyte levels, normal human hematocrits vary from 37 percent or lower to about 52 percent for whole blood, measured after a very high speed spin. To achieve concentrations of 3 fold or higher, some erythrocyte removal is necessary. However, the tensile strength of concentrated plasma gels diminish as the level of erythrocyte contamination increases. The concentration of erythrocytes in the final concentrate should be less than 3 to 5 percent to provide effective haemostatic properties. The device of this invention is intended to remove as much of the erythrocytes as is technically practical with the system, although trace contamination is accept able. For applications where sealant activities are not desired, higher levels of erythrocytes are tolerable.
Regarding volume, both the depth filter and the beads reduce the liquid volumes being processed. Because of this volume loss, only from 14 to 17 percent volume yields of effective haemostatic wound-healing product is generally obtained from average patient blood with the device of this invention. To make an effective product, the depth filter volume is selected to retain about 50 percent of the anti-coagulated blood (blood containing anticoagulant) and product about a 50 percent yield of PRP. The amount of the beads, in water absorption units, is selected to retain water equaling about 67 percent of the PRP volume.
Regarding accuracy, the amount of the depth filter and beads in each system is carefully selected to yield an optimum product. However, because of the wide range of hematocrit levels in patient populations, an approximate balance of components is required.
If too much blood is added to the device, there is a greater chance that the product will have a substantial erythrocyte contamination, and the final product will be less concentrated than desired because the volume exceeds the practical capacity of the depth filter. Because the volume retained by the depth filter is about half the total volume of blood to be processed, if the volume of blood introduced into the device is too small, a substantially lower volume of PRP will be delivered to the beads. For example, if the blood volume is low by only 25 percent, this will result in only 50 percent of the desired volume being delivered to the beads. If the volume of PRP contacting the beads is low by 33 percent or more, no product will be recovered because the beads will always absorb 67 percent of the targeted PRP volume. If the volume contacting the beads is only short by 17 percent, this will yield half of the desired volume of final product with twice the desired concentration (and hence of little value as a hemostat). In other words, a small error in the volume of blood introduced into the device is amplified into a large error in final product volume and concentration factor.
The systems can be designed to specifically match the hematocrit levels of the particular patient's blood to be processed. For a single optimized universal device, the device is optimized for the average patient blood, using fixed volumes of depth filter and blood, and a fixed bead water absorption capacity.
If it is desirable to tolerate inaccuracy of introduced blood volume, the device can incorporate an overflow chamber as described in provisional patent application Ser. No. 60/654,718 filed Feb. 17, 2005 and concurrently filed application Ser. No. 11/342,761, now U.S. Pat. No. 7,708,152, issued on May 4, 2010, the contents of which are hereby incorporated by reference.
EXAMPLE
Standard System Operation
Blood was processed with a device as shown and described in this application.
1) The initial spin was continued for 10 seconds at 250 rpm. This spin allows beads to be flung out into the cage under sufficiently low rpm that the initial imbalance does not generate excessive vibration. The outer ends of the rakes (the outermost tines) level the beads around the perimeter of the basket to balance the beads. 2) The erythrocytes were separated with the an erythrocyte separation spin of 3200 rpm for 90 seconds, packing the erythrocytes into the depth filter. 3) The PRP was concentrated by slowing the spin to 50 rpm for 45 seconds, draining PRP into the concentrator chamber and mixing the PRP with the beads. 4) The PRP concentrate was then removed from the beads by a final high-speed spin at 3200 rpm for 45 seconds.
The rates of acceleration and deceleration between stages were moderated to reduce vibration.
The process parameters were as follows:
Start Volume
150 cc
Retained by depth filter
75 cc
Recovered concentrate
23 cc
Platelet count
3 fold increase over whole blood
Fibrinogen concentration
2.8-3.2 fold increase over while blood
Erythrocytes in product
Undetected (less than 1%) | Disclosed is a separator-concentrator, such as for separating and concentrating platelet-rich-plasma (PRP) from whole blood that is suitable for office use or emergency use for trauma victims. The PRP separator comprises a motorized centrifugal separation assembly and a concentrator assembly. The centrifugal separation assembly comprises a centrifugal drum separator and a motor having a drive axis connected to the centrifugal drum separator. The concentrator assembly comprises a water-removal module for preparing PRP concentrate. | 0 |
RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional Application Ser. No. 61/940,542, filed under 35 U.S.C. §111(b) on Feb. 17, 2014, the disclosure of which is incorporated herein by reference in its entirety.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH
[0002] This invention was made with government support under Grant Number 0933250 awarded by the National Science Foundation. The government has certain rights in the invention.
BACKGROUND OF THE INVENTION
[0003] Lignocellulosic biomass, also referred to as biomass, includes waste materials such as corn stover, sawdust, straws, bagasse, municipal solid waste (paper and cardboard), and dedicated lignocellulose crops such as poplar, miscanthus , and switchgrass. These agricultural and waste materials are being developed as alternate domestic sources for production of carbon-based products such as fuels, chemicals, and the like. Lignocellulosic biomass is an attractive feedstock because it is an abundant, domestic, renewable source that can be converted to carbon-based chemicals or liquid transportation fuels.
[0004] Terrestrial biomass (lignocellulosic material) is composed of three major components: cellulose (30-50%), a highly crystalline polymer of cellobiose (a glucose dimer); hemicellulose (15-30%), a complex amorphous polymer of five-(pentose) and six-(hexose) carbon sugars; and lignin (5-30%), a highly cross-linked amorphous polymer of phenolic compounds. Lignin is a polyphenyl propanoid macromolecular assembly that is covalently cross-linked to hemicellulose. These components of biomass can serve as a source of carbon-based feedstock for fuel and chemical production in much the same way that crude oil serves as the carbon feedstock in petrochemical refineries. Cellulose and hemicellulose are the major polysaccharide components which, when hydrolyzed into their sugars, can be converted into ethanol or butanol fuel, polymer precursors such as 1,3-propanediol, lactic acid, or other products through various fermentation methods. These sugars also form the feedstock for production of a variety of chemicals and polymers through chemical conversion or fermentation. However, the complex and compact structure of lignocellulosic biomass renders this feedstock largely impenetrable to water, catalysts, or enzymes used to hydrolyze its constituent polysaccharides to monomeric sugars (saccharification).
[0005] In its natural state, cellulose is highly crystalline in structure with individual cellulose polymer chains held together by a strong hydrogen bonding network and van der Waals forces. The individual cellulose chains are linear condensation polymer molecules of anhydroglucose units covalently linked by β-1,4 glycosidic bonds with degrees of polymerization (dp) ranging from, typically, 1,000 to 15,000 units. The high crystallinity of cellulose, while imparting structural integrity and mechanical strength to the material, renders it recalcitrant towards hydrolysis aimed at producing glucose (which is a feedstock for producing fuels and chemicals) from this polysaccharide.
[0006] In lignocellulosic biomass, crystalline cellulose fibrils are embedded in a less well-organized hemicellulose matrix which, in turn, is linked to lignin. Hydrolysis of cellulose and hemicellulose polysaccharides into their monomeric sugars, glucose, xylose, and other sugars, provides the basic precursors useful for producing fuels (i.e., ethanol or butanol) and chemicals from biomass via the sugar platform. However, biomass is not easily penetrated by water or enzymes and must be pretreated to realize high yields of sugars during enzymatic hydrolysis of the polysaccharides. Enzyme hydrolysis is often favored over mineral acid-catalyzed hydrolysis since mineral acids produce sugar degradation products such as hydroxymethyl furfural (HMF), furfural, levulinic acid, and formic acid. These sugar degradation products are inhibitory to downstream fermentation steps.
[0007] Due to the structural complexity of lignocellulosic biomass and the inaccessibility of biomass polysaccharides to water and catalysts, hydrolysis rates to the monomeric sugars that form the sugar platform are extremely slow. Proper pretreatment of the biomass is therefore required to enable efficient saccharification of the cellulose and hemicellulose components to their constituent sugars. The pretreatment generally required for biomass is more severe than that required for starch-based (i.e. corn grain) ethanol production. The hydrolysis of biomass polysaccharides (cellulose and hemicellulose) also requires a complex mixture of enzymes (cellulases and hemicellulases) due to the heterogeneity of hemicellulose and the crystalline nature of cellulose in contrast to the less complex amorphous structure of starch-based feedstocks (amylose). Effective pretreatment and hydrolysis (saccharification) of biomass present key challenges in the development of sustainable processes for chemical and fuel production from biomass. Current pretreatment approaches suffer from slow reaction rates of cellulose and hemicellulose hydrolysis (using cellulases and hemicellulases), low sugar yields, and degradation of biomass or pretreatment chemicals due to the severity of the current pretreatment processes.
[0008] Furthermore, enzymatic access to cellulose, for hydrolysis, is restricted by hemicellulose and lignin. Neither the water molecules nor the catalysts for hydrolysis (saccharification) are able to easily penetrate the crystalline matrix of cellulose. As a remedy, slow reaction rates have been increased by pretreatment involving an ionic liquid incubation of the biomass, which is capable of partially dissolving the cellulosic and hemicellulosic portion at various temperatures ranging between about 120° C. and about 160° C., and resulting in higher digestibility yields. However, the high temperature incubation is not favorable from an energy input standpoint. High temperatures can also lead to degradation of the feedstock and ionic liquid, as well as the promotion of unwanted side reactions. Thus, there remains a need for efficient methods of enhancing saccharification of cellulose and hemicellulose from biomass for fuel and chemical production that do not require high temperatures.
SUMMARY OF THE INVENTION
[0009] Provided herein is a method of pretreating lignocellulosic biomass having a lignin component, a hemicellulose component, and a cellulose component, for conversion to sugar, the method comprising contacting the biomass with an oxidizing agent at a first temperature for a first period of time sufficient to at least partially remove or decompose the lignin component, thereby producing LOX biomass; contacting the LOX biomass with an ionic liquid at a second temperature for a second period of time, thereby producing a first mixture comprising IL and LOX biomass; contacting the first mixture with a solvent, thereby producing a second mixture comprising LOXIL-treated biomass and solvent, wherein the IL is substantially soluble in the solvent and at least one of the cellulose component or the hemicellulose component is substantially insoluble in the solvent; and separating the LOXIL-treated biomass from the solvent to produce pretreated lignocellulosic biomass.
[0010] In certain embodiments, the lignocellulosic biomass comprises poplar, corn stover, switchgrass, agricultural or forest wastes, other lignocellulosic biomass sources, or a combination thereof.
[0011] In certain embodiments, the separating comprises mixing the second mixture so as to precipitate the LOXIL-treated biomass from the IL. In particular embodiments, the method further comprises the step of washing the precipitated LOXIL-treated biomass with the solvent so as to displace the IL. In particular embodiments, the method further comprises removing liquid from the precipitated LOXIL-treated biomass through filtration. In certain embodiments, the method further comprises the step of contacting the pretreated lignocellulosic biomass with enzymes capable of hydrolyzing at least one of cellulose or hemicellulose, and converting at least one of the cellulose component or the hemicellulose component to hexose and/or pentose sugars. In certain embodiments, the enzymes comprise a mixture of cellulases and/or hemicellulases.
[0012] In certain embodiments, the method further comprises the step of contacting the second mixture with an acid catalyst to hydrolyze at least one of the hemicellulose component or cellulose component. In certain embodiments, the method further comprises the step of contacting the pretreated lignocellulosic biomass with enzymes capable of hydrolyzing at least one of cellulose or hemicellulose, and converting at least one of the cellulose component or the hemicellulose component to hexose and/or pentose sugars. In certain embodiments, the enzymes comprise a mixture of cellulases and/or hemicellulases.
[0013] In certain embodiments, the first period of time ranges from about 1 hour to about 48 hours. In certain embodiments, the first temperature ranges from about 18° C. to about 40° C. In certain embodiments, the oxidizing agent is combined in an alkaline solution. In particular embodiments the alkaline component is derived from CaO, Ca(OH) 2 , NH 4 OH or NaOH. In particular embodiments, the alkaline oxidizing solution comprises NaOH and H 2 O 2 . In certain embodiments, the alkaline oxidizing solution is mixed with the biomass at a NaOH-to-biomass ratio of about 10 wt %, and a H 2 O 2 -to-biomass ratio of about 12.5 wt %. In certain embodiments, the oxidizing agent is selected from the group consisting of: hydrogen peroxide, calcium hypochlorite, chlorine dioxide, ozone, potassium peroxymonosulfate, and ammonium persulfate.
[0014] In certain embodiments, the second temperature ranges from about 20° C. to about 75° C. In certain embodiments, the second period of time ranges from about 1 hour to about 24 hours.
[0015] In certain embodiments, the LOX biomass is at least partially dried prior to being contacted with the ionic liquid. In certain embodiments, the LOX biomass is filtered prior to being contacted with the ionic liquid.
[0016] In certain embodiments, the ionic liquid comprises a cation selected from the group consisting of: imidazolium, pyrroldinium, pyridinium, phosphonium, and ammonium. In certain embodiments, the ionic liquid has the structural formula of Formula I:
[0000]
[0000] wherein each of R 1 , R 2 , and R 3 is independently hydrogen, an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, or an alkene group having 2 to 8 carbon atoms, and A is a halide, acetate, formate, dicyanamide, carboxylate, or phosphate anion. In particular embodiments, the alkyl group is substituted with sulfone, sulfoxide, thioether, ether, amide, or amine. In particular embodiments, the alkene group is an allyl or vinyl group. In particular embodiments, the halide is a chloride, fluoride, bromide, or iodide. In certain embodiments, the ionic liquid consists essentially of 1-ethyl-3-methylimidazolium acetate. In certain embodiments, the ionic liquid consists essentially of 1-n-butyl-3-methylimidazolium chloride. In certain embodiments, the ionic liquid consists essentially of 1-allyl-3-methyl imidazolium chloride or allyl-imidazlium chloride. In certain embodiments, the ionic liquid consists essentially of 3-methyl-N-butylpyridinium chloride.
[0017] In certain embodiments, the solvent is selected from the group consisting of: water, ethanol, methanol, and acetonitrile.
[0018] In certain embodiments, the method further comprises the step of washing the LOXIL-treated biomass with a second solvent, wherein at least one of the cellulose component or the hemicellulose component is substantially insoluble in the second solvent, and the IL is substantially soluble in the second solvent. In particular embodiments, the washing fractionates and separates the cellulose component and the hemicellulose component. In particular embodiments, the second solvent is selected from the group consisting of: water, ethanol, methanol, and acetonitrile.
[0019] In certain embodiments, the method further comprises the step of recovering the IL by at least one of: distillation, membrane separation, solid phase extraction, or liquid-liquid extraction.
[0020] In certain embodiments, the contacting of the biomass with the oxidizing agent comprises combining the biomass with an oxidizing solution at about 10% (w/w) solids loading. In particular embodiments, the method further comprises the step of mixing the combination of biomass and oxidizing solution.
[0021] In certain embodiments, the contacting of the LOX biomass with the ionic liquid comprises combining the LOX biomass with the ionic liquid at a range of from about 5% to about 20% (w/w) solids loading. In particular embodiments, the method further comprises the step of mixing the combination of LOX biomass and ionic liquid.
[0022] Further provided is the pretreated lignocellulosic biomass produced from the method described herein.
BRIEF DESCRIPTION OF THE DRAWING
[0023] The patent or application file may contain one or more drawings executed in color and/or one or more photographs. Copies of this patent or patent application publication with color drawing(s) and/or photograph(s) will be provided by the U.S. Patent and Trademark Office upon request and payment of the necessary fees.
[0024] FIG. 1 : Drawing of the structure of biomass containing cellulose, hemicellulose, and lignin. The cellulose, shown in blue, is a highly crystalline polymer of glucose or hexose, and a source of fermentable sugar. The hemicellulose, shown in green, is an amorphous polymer of xylose, hexose, and other fermentable sugars. The lignin, shown in black, is a cross-linked polymer network of phenyl propanoid subunits.
[0025] FIGS. 2A-B : Flow charts of exemplary ionic liquid pretreatment processes. EMIM-OAc is an example of an ionic liquid. The mixture of NaOH and H 2 O 2 is an example of an alkaline oxidizing agent. FIG. 2A is a high-temperature ionic liquid pretreatment strategy for enzymatic hydrolysis of lignocellulosic feedstocks. FIG. 2B shows the same pretreatment process coupled with the method described herein, resulting in a low-temperature ionic liquid treatment process.
[0026] FIGS. 3A-B : Total sugar yield for poplar feedstock with a fixed enzyme loading per gram of glucan. These graphs illustrate the difference in yield resulting from methods involving a low temperature ionic liquid pretreatment step ( FIG. 3A ), as described herein, and ( FIG. 3B ) a high temperature ionic liquid treatment step.
[0027] FIGS. 4A-B : Comparative yields of glucose ( FIG. 4A ) and xylose ( FIG. 4B ) for poplar feedstock, shown as a function of ionic liquid treatment temperature with a fixed enzyme loading per gram of feedstock using water as an anti-solvent unless otherwise noted.
[0028] FIG. 5 : Chart illustrating examples of possible sugar platform products.
[0029] FIG. 6A : Comparative XRD intensity as a function of diffraction angle 20 with a poplar substrate. LOX poplar was incubated in an alkaline hydrogen peroxide (AHP) mixture, as described in Example 2. Incubation times and temperatures are noted in the legand for the lignin oxidation and IL treatment steps.
[0030] FIG. 6B : Same intensity plots as shown in FIG. 6B , depicted separately to better visualize each plot. (a) LOX 24 h at 25° C.; (b) LOX 6 h at 25° C.; (c) 4 h at 50° C. IL-treated; (d) native poplar; and (e) 6 h at 25° C. LOX followed by 4 h at 50° C. IL incubation.
DETAILED DESCRIPTION OF THE INVENTION
[0031] Throughout this disclosure, various publications, patents and published patent specifications are referenced by an identifying citation. The disclosures of these publications, patents and published patent specifications are hereby incorporated by reference into the present disclosure in their entirety to more fully describe the state of the art to which this disclosure pertains.
[0032] Due to the structural complexity of lignocellulosic biomass, enzymatic inaccessibility to cellulose results in extremely slow enzymatic hydrolysis rates. One of the pathways to deconstruction of biomass to its constituent sugars is to utilize a pretreatment of substrates by chemical and/or thermal processes followed by enzymatic or acid-catalyzed hydrolysis. A number of these technologies have been developed to overcome the recalcitrance of this cellulosic carbon source to hydrolysis to its monomeric sugars. One such technology is ionic liquid (IL) incubation of biomass at various temperatures ranging between about 120° C. and about 160° C., which results in rapid and efficient enzyme hydrolysis. IL pretreatment produces amorphous cellulose that is accessible to water, catalysts, and enzymes, increasing the rate of hydrolysis of cellulose to glucose or soluble glucose oligomers and hemicellulose to its constituent sugars. However, with a one-step pretreatment of native lignocellulosic biomass consisting of ionic liquid incubation alone, high temperatures are often necessary to unravel the crystalline structure of cellulose. The native crystalline structure of cellulose is a major impediment to saccharification.
[0033] Provided herein is a method that reduces the energy input of IL incubation by lowering the ionic liquid incubation temperatures from 120-160° C. down to a range of from ambient temperatures to about 75° C. The method includes a low-temperature (such as room temperature) pre-processing step that precedes the ionic liquid incubation, where the pre-processing step involves lignin oxidation at ambient temperatures. This pre-processing step enables partial disruption of the biomass structure, and allows for low IL incubation temperatures with subsequently rapid saccharification as well as reduced biomass and ionic liquid degradation, contamination, and derivatization. The method can be used for any type of lignocellulosic biomass, including, but not limited to: poplar, switchgrass, rice straw, hardwood, softwood, herbaceous crops, recycled paper, waste paper, wood chips, pulp, paper wastes, waste wood, thinned wood, cornstalk, chaff, wheat straw, sugar cane stalk, bagasse, agricultural residual products, agricultural wastes, and combinations thereof.
[0034] Though IL incubation is specified in this description for illustrative purposes, the method of the present disclosure can be coupled with any suitable pretreatment step to produce advantageous results such as reduced required energy input and side reactions. Specifically, it is to be understood that the presently disclosed pre-processing step can be coupled with any of several non-IL pretreatment processes. Some non-limiting examples of other suitable pretreatment processes the pre-processing step can be coupled with include, but are not limited to: dilute acid hydrolysis, ammonia fiber explosion, pH-controlled liquid hot water treatment, aqueous ammonia recycling processes, and lime pretreatments. When the preprocessing step is coupled with an ionic liquid treatment step, the result is a dramatically lowered required temperature for the ionic liquid pretreatment step. Suitable ionic liquid pretreatment steps include, but are not limited to, those described in U.S. Pat. No. 7,674,608, U.S. Pat. No. 8,030,030, and U.S. Pat. No. 8,236,536, the entire disclosures of which are incorporated herein by reference. In certain embodiments, coupling a lignin oxidation step with ionic liquid pretreatment lowers the required ionic liquid pretreatment temperature by about 100° C.
[0035] High-temperature ionic liquid pretreatment, ranging between about 120° C. and about 160° C., has previously been necessary to unravel the crystalline structure of cellulose in order to make it accessible to water and enzymes and thereby increase the rate of hydrolysis of cellulose to glucose or soluble glucose oligomers and hemicellulose to its constituent sugars such as xylose or soluble xylose oligomers. An example of an ionic liquid pretreatment is depicted in FIG. 2A . In the method described herein, a lignin oxidation step at ambient, or close to ambient, temperature and ambient pressure precedes the ionic liquid incubation (or other pretreatment step). This coupled pretreatment, a non-limiting example of which is depicted in FIG. 2B , enables partial deconstruction or redistribution of the lignin and the hemicellulose portions of lignocellulosic biomass, enables disruption of the crystalline structure of cellulose, and allows for the formation of dramatically more digestible amorphous cellulose and hemicellulose substrates without requiring high operation temperatures. Similar or higher digestibility yields can be gained at low IL incubation temperatures utilizing this method compared to that gained at elevated temperatures, as illustrated by FIGS. 3-4 and the examples described herein.
[0036] The method of the present disclosure involves conducting an oxidative pre-processing step prior to an IL incubation pretreatment. The oxidative pre-processing step is a lignin oxidation step, which can then be followed by low-temperature ionic liquid incubation. In certain embodiments, the oxidative pre-processing step significantly improves the efficiency of the yield and reaction rates of saccharification of lignocellulosic biomass while minimizing degradation or derivatization of biomass polysaccharides or IL.
[0037] In the lignin oxidation step, chemical delignification is achieved utilizing one or more suitable oxidizing agents. Suitable oxidizing agents include, but are not limited to: potassium peroxymonosulfate, ammonium persulfate, hydrogen peroxide (such as alkaline hydrogen peroxide solutions), calcium hypochlorite (Ca(OCl) 2 ), chlorine dioxide (ClO 2 ), ozone (O 3 ), t-butylhydroperoxide, dibenzoylperoxide, dimethyldioxirane, NaOCl, peracetic acid, trifluoroperacetic acid, perbenzoic acid, monoperoxyphthalic acid, metachlorobenzoic acid, 2-iodoxybenzoic acid, pyridine sulfur trioxide, bis(acetoxy)iodobenzene, bis(trifluoroacetoxy)iodobenzene, NaOBr, lead tetracetate, oxalyl chloride with dimethylsulfoxide (DMSO), nitric acid, nitrous oxide, sodium perborate (PBS), silver oxide, potassium nitrate, sulfuric acid, peroxymonosulfuric acid, osmium tetroxide, compounds having a hexavalent chromium atom, or a combination thereof.
[0038] The lignin oxidation step is conducted at ambient, or close to ambient, temperatures and pressure. In certain embodiments, the biomass is treated with the oxidizing agent(s) for a time period ranging from about 4 hours to about 48 hours. In one non-limiting example, the biomass is treated for about 6 hours. Once biomass is taken through the lignin oxidation step, the liquid phase is removed by filtration or other separation technique, and the solid is added directly to IL (or other pretreatment chemical) for incubation with or without drying. Prior washing is not necessary, though is possible.
[0039] The ionic liquid incubation typically lasts for a period of time of from about 1 hour to about 24 hours, and is typically at a temperature ranging from about 20° C. to about 75° C. In one non-limiting example, the temperature of the IL incubation is about 50° C. The optimal duration and temperature of the IL incubation step depend on the processing parameters of the lignin oxidation step, as well as the biomass source and feedstock properties such as composition, particle size, and moisture content. Washing steps after the lignin oxidation step and prior to IL treatment are not required, though may be included.
[0040] Any ionic liquid capable of swelling or dissolving cellulose or hemicellulose, such as those having a cation structure that includes imadazolium, pyrroldinium, pyridinium, phosphonium, or ammonium, can be used in combination with the lignin oxidation step of the present disclosure. Suitable ionic liquids for use in a coupled pretreatment method include, but are not limited to, ionic liquids represented by Formula I:
[0000]
[0000] wherein each of R 1 , R 2 , and R 3 is hydrogen, an alkyl or alkoxy group having 1 to 8 carbon atoms, or an alkene group having 2 to 8 carbon atoms, wherein the alkyl group may be substituted with sulfone, sulfoxide, thioether, ether, amide, or amine; and A is a halide, acetate, formate, dicyanamide, carboxylate, phosphate, or other anion.
[0041] When the oxidative pre-processing step is coupled with ionic liquid pretreatment, the IL incubation results in partial or complete dissolution or swelling of the biomass. In certain embodiments, the IL incubation is then followed by rapid quenching with the addition of a cellulose and/or hemicellulose “anti-solvent” such as water, alcohol, acetonitrile, or other hydrophilic solvent in which the IL is soluble. The high affinity of anti-solvent for the IL leads to solute displacement of IL and recovery of a precipitated biomass (also referred to as regenerated biomass). The regenerated biomass is in an amorphous and solvent-swollen state. In solvent-swollen cellulose, the degree of crystallinity of the cellulose is progressively reduced as the extent of swelling increases. The regenerated biomass can be separated from the IL/anti-solvent solution through mechanical separations such as, but not limited to, centrifugation or filtration. In certain embodiments, the precipitated amorphous state is then taken through enzyme hydrolysis without drying. The saccharification can be performed with or without a catalyst. Suitable catalysts include, but are not limited to: H 2 SO 4 , HCl, HBr, HNO 3 , CH 3 COOH, HCOOH, HClO 4 , H 3 PO 4 , paratoluene sulfonic acid (PTSA), or a mixture or complex thereof. The ionic liquid can also be recovered from the anti-solvent/IL mixture by flash distillation, solvent extraction, liquid-liquid extraction, membrane separation, or ion exchange techniques.
[0042] Disruption of cellulose, hemicellulose, and lignin linkages increases the accessibility of polysaccharides to water, catalysts, and/or enzymes, thereby increasing the rate of hydrolysis of cellulose to glucose or soluble glucose oligomers and hemicellulose to its constituent sugars. The lignin oxidation at ambient pressure and ambient, or close to ambient, temperature, preceding a low temperature ionic liquid incubation, causes partial deconstruction or redistribution of the lignin and hemicellulose portions of lignocellulosic biomass, enabling disruption of the crystalline structure of cellulose and the formation of dramatically more digestible amorphous cellulose and hemicellulose substrates without requiring high operation temperatures. This method is capable of achieving similar or higher digestibility yields in a two-step process with low IL incubation temperatures, compared to those achieved with a one-step IL incubation process at elevated temperatures.
[0043] Without wishing to be bound by theory, it is believed the improvement and efficiency of ionic liquid pretreatment at low temperatures resulting from the lignin oxidation pre-processing step is at least partly attributable to the oxidation of ferulate and other cross-links to hemicellulose, as well as the mild oxidation and solubilization of lignin. Alteration of linkages between monolignols and breakage in the lignin backbone lead to structural disruptions and smaller chain lengths. This results in lower hydrophobicity of the cell wall matrix and a lower glass transition temperature of lignin, which, in turn, allows for more efficient ionic liquid pretreatment at low temperatures.
[0044] The method of the present disclosure has many advantages. For example, the method increases the sustainability of lignocellulose processing, reduces energy input with low temperature IL incubation, increases the opportunity for effective heat integration and use of waste heat, increases the ease of recycling by reducing the hemicellulose fraction in IL/solvent, produces effective saccharification (hydrolysis to monomeric sugars) at very low enzyme loadings, and provides a renewable non-food-based source for sugar platform chemicals.
[0045] The method of the present disclosure can be utilized to enhance saccharification of cellulose from biomass for fuel and chemical production, and is useful for producing a variety of valuable products from monomeric sugars. Possible products from the sugar platform include, but are not limited to: 1,3-propanediol, which is currently derived from corn grain (amylose) through glucose fermentation and is a green polymer precursor for the production of carpet, textiles, cosmetics, personal care products, and home care products; succinic acid, which is a polymer precursor for adhesives and coatings; and lactic acid, from the fermentation of glucose, which is a polymer precursor for packaging; PET precursors, such as polyethylene glycol from ethanol, which is a polymer precursor used in packaging; 1,4-butanediol (BDO); butylene glycol; furfural from xylose dehydration, which is used in resins, nylon, and as a platform for other classes of chemicals; and hydroxymethylfurfural (HMF), from glucose dehydration, which is used in lubricants and as a platform for the classes of chemicals. FIG. 5 shows a chart of some of the various sugar platform products that are possible from utilizing the hemicellulose, cellulose, and lignin of biomass.
[0046] Further described are methods to optimize the processing conditions for maximal sugar recovery and hydrolysis. For example, methods of minimizing the partitioning of xylan to IL/solvent to ease IL recovery are entirely within the scope of the present disclosure.
EXAMPLES
[0047] In the following examples, lignicellulosic biomass samples taken through both lignin oxidation and IL treatment steps with no drying prior to hydrolysis are referred to as “LOXIL-treated biomass”. Samples taken through only IL treatment with no drying prior to hydrolysis are referred to as “IL-treated biomass.”
[0048] An example of the preparation of LOXIL-treated biomass samples used in the following examples involves combining biomass with an oxidizing solution at 10% solids loading and incubating at room temperature from 4 hours to 24 hours with mixing using an orbital shaker water bath, a magnetic stirrer, or rollers. After lignin oxidation, liquid is removed from the solids through filtration. The solids are combined with 1-ethyl-3-methylimidazolium acetate (EMim-OAc) with a solids concentration of 5-20% in IL with or without drying prior to IL treatment. Samples are incubated at 20° C. to 75° C. for 1 hour to 24 hours with mixing. Anti-solvent is added to the IL incubation container and mixed vigorously, precipitating the biomass from EMim-OAc. The sample is briefly filtered or centrifuged and supernatant is removed. The solid is washed with solvent until the IL is displaced. After washing, the liquid is removed from the regenerated biomass solid through filtration.
[0049] An example of the preparation of the IL-treated biomass samples used in the following examples involves combining biomass with ionic liquid, 1-ethyl-3-methylimidazolium acetate (EMim-OAc), at 5 to 20% (w/w) solids loading and incubating at temperatures ranging from 20° C. to 75° C. for a time period of from 1 to 24 hours with mixing. Anti-solvent is added to the IL incubation container to precipitate the biomass from EMim-OAc, then mixed vigorously. The sample is filtered or centrifuged and the supernatant is removed. The solid is washed with solvent until the IL is displaced.
[0050] The terms “LOX,” “LOX biomass,” or “wet LOX” refer to biomass that is only taken through lignin oxidation at low temperatures ranging from room temperature to 40° C., from 4 hours to 24 hours. An example of the preparation of LOX biomass samples used in the following examples involves combining biomass with an oxidizing solution at 10% (w/w) solids loading and incubating at room temperature from 4 hours to 24 hours with mixing using an orbital shaker water bath, a magnetic stirrer, or rollers. All modes of mixing give similar results. After incubation, liquid is removed from the biomass solid through mechanical separation such as filtration.
[0051] Poplar, switchgrass, and corn stover were used as the biomass feedstocks in the examples below. However, many other types of biomass feedstocks can be used. The following Table 1 indicates the compositions of native biomass.
[0000]
TABLE 1
Composition of native biomass analyzed with the National Renewable
Energy Laboratory (NREL) protocol “Determination of Structural
Carbohydrates and Lignin in Biomass” Crystallinity Index
was estimated from X-ray powder diffraction data. Lignin includes
both acid soluble and insoluble lignin.
Crystallinity
Substrate
Index (Crl)
Glucan (%)
Xylan (%)
Lignin (%)
Poplar
36
47 ± 1
16 ± 0
26 ± 1
Corn Stover
33
34
18
15
Switchgrass
36
32 ± 0
19 ± 1
20 ± 1
Example 1
Structure of Pretreated Biomass
[0052] X-ray powder diffraction (XRD) data were obtained to assess crystallinity for samples of LOX, LOXIL-treated, IL-treated, and native poplar. LOX, LOXIL-treated, and IL-treated poplar were dried under vacuum at 40° C. overnight. Samples were then ground using a mortar and pestle. Smooth films of powder for X-ray powder diffraction data collection were prepared. XRD data were collected at room temperature with a PANalytical XPERT′ PRO powder diffractometer with an Xcelerator′ detector using Nickel-filtered Cu-Kα radiation. Samples were scanned over the angular range 6.0-45.0° 20 with a step size of 0.05°, and step time of 10 seconds. FIGS. 6A-6B show the comparative XRD intensity as a function of diffraction angle 20 with a poplar substrate. LOX poplar was incubated in an alkaline hydrogen peroxide (AHP) mixture, described in Example 2 below. Diffraction data from bottom to top of FIG. 6B with incubation times and temperatures are: (a) LOX 24 h at 25° C.; (b) LOX 6 h at 25° C.; (c) 4 h at 50° C. IL-treated; (d) native poplar; and (e) 6 h at 25° C. LOX followed by 4 h at 50° C. IL incubation. (The baselines are offset for clarity.)
[0053] As seen in FIGS. 6A-6B , LOXIL-treated poplar produced amorphous cellulose whereas cellulose from IL-treated poplar, LOX poplar, and native poplar was highly crystalline. The XRD results indicate the two-step pretreatment process of room temperature lignin oxidation coupled with low temperature IL incubation disrupts cellulose crystallinity, whereas low temperature IL incubation alone or lignin oxidation alone increases the crystallinity of cellulose. This is further displayed in Table 2.
[0000]
TABLE 2
Crystallinity index, Crl, of samples shown
in FIGS. 6A-6B, estimated from the XRD data
Poplar Substrates
Crl
Native
36
IL-treated (4 h at 5° C.)
51
LOX (6 h at 25° C.)
58
LOX (24 h at 25° C.)
61
LOX (6 h at 25° C.),
10
IL-treated (4 h at 50° C.)
Example 2
Enzyme Hydrolysis of Wet LOXIL-Treated Poplar with Lignin Oxidation at Room Temperature for 6 Hours, Using Alkaline Hydrogen Peroxide (AHP) Solution as the Oxidizing Solution, IL Treatment at 50° C. for 4 Hours and 5 wt % Loading, and Water as the Anti-Solvent
[0054] Poplar was incubated for 6 hours in an oxidizing solution of a 10 wt % ratio of NaOH to biomass and a 12.5 wt % ratio of H 2 O 2 to biomass. Water was added to a final concentration of 10% (w/v) biomass solids in the liquid solution. After lignin oxidation, the liquid was removed from the sample through mechanical means such as filtration, producing LOX poplar. The filtered LOX poplar was dried at 40° C. to constant weight. These solids were then combined with EMim-OAc at a 5 wt % biomass-to-ionic-liquid ratio for incubation for 4 hours at 50° C. The anti-solvent for this example was water. The anti-solvent-washed biomass was LOXIL-treated poplar.
[0055] Batch enzymatic hydrolysis of wet LOX, LOXIL-treated, IL-treated (4 hours at 50° C.), and native poplar was carried out in capped Erlenmeyer flasks immersed in an orbital shaker water bath at 50° C. for 24 hours. A commercial cellulase enzyme mixture, Cellic CTec2 (Novozyme), was used at an enzyme loading of 5.1 mg protein per gram of glucan, and a biomass concentration of about 1% (w/v). Native, IL-treated, LOX, and LOXIL-treated poplar were hydrolyzed using the same enzyme stock solution. Solutions were buffered with 0.05M sodium citrate, pH 4.8. Glucose and xylose concentrations in the hydrolysate were measured via high performance liquid chromatography (HPLC).
[0056] The average and standard deviation of replicate samples of 24-hour hydrolysis yields of glucose from glucan and xylose from xylan from treated and untreated poplar are shown in Table 3. Yields are reported as a percentage of monomeric sugars obtained from enzyme hydrolysis divided by the theoretical concentration of monomeric sugar based on the initial mass and composition of untreated biomass. Enzymatic hydrolysis glucose and xylose yields for LOXIL-treated poplar were 20 and 39 times greater than that of native poplar, respectively.
[0000]
TABLE 3
Twenty-four hour enzymatic hydrolysis yields of monomeric
sugars for treated and native poplar substrates. 10 mg/ml
of treated or native poplar samples were hydrolyzed at an
enzyme loading of 5.1 mg protein per gram of glucan. Anti-
solvent for LOXIL and IL-treated poplar was water.
% Glucose Yield
% Xylose Yield
Poplar Substrates
(Enhancement*)
(Enhancement*)
LOX (6 h at 25° C.),
80 ± 2
(20)
39 ± 3
(39)
IL-treated (4 h at 50° C.)
IL-treated (4 h at 50° C.)
16 ± 4
(4)
6 ± 1
(6)
LOX (6 h at 25° C.)
11 ± 0
(>2)
1 ± 0
(1)
Native
4 ± 0
1 ± 0
*Yield Enhancement is defined as the ratio of yield for treated biomass divided by that of untreated ‘native’ biomass.
Example 3
Enzyme Hydrolysis of Wet LOXIL-Treated Poplar with Lignin Oxidation at Room Temperature for 6 Hours, Using Alkaline Hydrogen Peroxide (AHP) Solution as the Oxidizing Solution, IL Treatment at 50° C. for 4 Hours and 5 wt % Solids Loading, and Ethanol as the Anti-Solvent
[0057] Poplar was incubated at 25° C. for 6 hours in an oxidizing solution comprised of a 10 wt % ratio of NaOH to biomass and a 12.5 wt % ratio of H 2 O 2 to biomass, as described in Example 2, to produce LOX poplar. For LOXIL-treated poplar, LOX samples were incubated in IL at 50° C. for 4 hours as described in Example 2. The anti-solvent ethanol was used to displace IL and to produce LOXIL-treated or IL-treated poplar. Batch enzymatic hydrolysis of wet LOX, LOXIL-treated, IL-treated, and native poplar was carried out as described in Example 2.
[0058] The average and standard deviation of replicate samples of the 24-hour hydrolysis yields are shown in Table 4 as a percentage of monomeric sugars obtained from enzyme hydrolysis divided by the theoretical concentration of monomeric sugar based on the initial mass and composition of untreated biomass. Glucose and xylose yields for LOXIL-treated poplar were at least 20 and 54 times greater than that of native poplar, respectively.
[0000]
TABLE 4
Twenty-four hour enzymatic hydrolysis yields of monomeric
sugars for treated and native poplar substrates. 10 mg/ml
of treated or native poplar samples were hydrolyzed at an
enzyme loading of 5.1 mg protein per gram of glucan. Anti-
solvent for LOXIL-treated and IL-treated polar was ethanol.
% Glucose Yield
% Xylose Yield
Poplar substrates
(Enhancement*)
(Enhancement*)
LOX (6 h at 25° C.),
80 ± 0
(20)
54 ± 2
(54)
IL-treated (4 h at 50° C.)
IL-treated (4 h at 50° C.)
11 ± 1
(>2)
4 ± 1
(4)
LOX (6 h at 25° C.)
11 ± 0
(>2)
1 ± 0
(1)
Native
4 ± 0
1 ± 0
*Yield Enhancement is defined as the ratio of yield for treated biomass divided by that of untreated native biomass.
Example 4
Enzyme Hydrolysis of Wet LOXIL-Treated Poplar with Lignin Oxidation at Room Temperature for 6 Hours, Using Alkaline Hydrogen Peroxide (AHP) Solution as the Oxidizing Solution, IL Treatment at 50° C. for 4 Hours and 15 wt % Solids Loading, and Water as the Anti-Solvent
[0059] Poplar was incubated at 25° C. for 6 hours in an oxidizing solution comprised of a 10 wt % ratio of NaOH to biomass and a 12.5 wt % ratio of H 2 O 2 , as described in Example 2 except that the ratio of biomass to IL was increased to 15 wt % instead of 5 wt %. The anti-solvent water was used to displace IL and to produce LOXIL-treated or IL-treated poplar. Batch enzymatic hydrolysis of wet LOX, LOXIL-treated, IL-treated, and native poplar was carried out as described in Example 2.
[0060] The average and standard deviation of replicate samples of 24-hour hydrolysis yields of glucose from glucan and xylose from xylan from treated and untreated poplar are shown in Table 5. Yields are reported as a percentage of monomeric sugars obtained from enzyme hydrolysis divided by the theoretical concentration of monomeric sugar based on the initial mass and composition of untreated biomass. Glucose and xylose yields for LOXIL-treated poplar were 19 and 38 times greater than that of native poplar, respectively.
[0000]
TABLE 5
Twenty-four hour enzymatic hydrolysis yields of monomeric
sugars for treated and native poplar substrates. 10 mg/ml
of treated or native poplar samples were hydrolyzed at an
enzyme loading of 5.1 mg protein per gram of glucan. Anti-
solvent for LOXIL and IL-treated poplar was water.
% Glucose Yield
% Xylose Yield
Poplar Substrates
(Enhancement*)
(Enhancement*)
LOX (6 h at 25° C.),
78 d
(19)
38 d
(38)
IL-treated (4 h at 50° C.)
IL-treated (4 h at 50° C.)
16 ± 4
(4)
6 ± 1
(6)
LOX (6 h at 25° C.)
11 ± 0
(3)
1 ± 0
(1)
Native
4 ± 0
1 ± 0
*Yield Enhancement is defined as the ratio of yield for treated biomass divided by that of native biomass.
d Average of duplicates
Example 5
Enzyme Hydrolysis of Wet LOXIL-Treated Corn Stover with Lignin Oxidation at Room Temperature for 24 Hours, Using Alkaline Hydrogen Peroxide (AHP) Solution as the Oxidizing Solution, IL Treatment at 50° C. for 4 Hours and 5 wt % Solids Loading, and Ethanol as the Anti-Solvent
[0061] Corn stover was incubated at 25° C. for 24 hours in an oxidizing solution comprised of a 10 wt % ratio of NaOH to biomass and a 12.5 wt % ratio of H 2 O 2 to biomass, as described in Example 2, to produce LOX corn stover. For LOXIL-treated corn stover, LOX samples were incubated in IL for 4 hours at 50° C., as described in Example 2. The anti-solvent ethanol was used to displace IL and to produce LOXIL-treated corn stover. Batch enzymatic hydrolysis of wet LOXIL-treated and native corn stover was carried out as described in Example 2.
[0062] The 24-hour hydrolysis yields of glucose from glucan and xylose from xylan from LOXIL-treated and untreated corn stover are shown in Table 6. Yields are reported as a percentage of monomeric sugars obtained from enzyme hydrolysis divided by the theoretical concentration of monomeric sugar based on the initial mass and composition of untreated biomass. Glucose and xylose yields for LOXIL-treated corn stover were at least 3 and 7 times greater than that of native corn stover, respectively.
[0000]
TABLE 6
Twenty-four hour enzymatic hydrolysis yields of monomeric
sugars for treated and native corn stover substrates. 10
mg/ml of treated or native corn stover samples were hydrolyzed
at an enzyme loading of 5.1 mg protein per gram of glucan.
Anti-solvent for LOXIL corn stover was ethanol.
% Glucose Yield
% Xylose Yield
Corn Stover Substrates
(Enhancement*)
(Enhancement*)
LOX (24 h at 25° C.),
72.5 d
(>3)
51.5 d
(>7)
IL-treated (4 h at 50° C.)
IL-treated (4 h at 50° C.)
31 ± 0
17 ± 1
LOX (24 h at 25° C.)
40 ± 0
(>3)
35 ± 1
(5)
Native
24 d
7 d
*Yield Enhancement is defined as the ratio of yield for treated biomass divided by that of untreated biomass.
d Average of duplicates
Example 6
Enzyme Hydrolysis of Wet LOXIL-Treated Switchgrass with Lignin Oxidation at Room Temperature for 24 Hours, Using AHP Solution as the Oxidizing Solution, IL Treatment at 50° C. for 4 Hours with 5 wt % Solids Loading, and Ethanol as the Anti-Solvent
[0063] Switchgrass was incubated at 25° C. for 24 hours in an oxidizing solution comprised of a 10 wt % ratio of NaOH to biomass and a 12.5 wt % ratio of H 2 O 2 to biomass, as described in Example 2, to produce LOX switchgrass. For LOXIL-treated switchgrass, LOX samples were incubated in IL for 4 hours at 50° C. with 5 wt % biomass loading in IL, as described in Example 2. The anti-solvent ethanol was used to displace IL and to produce LOXIL-treated switchgrass. Batch enzymatic hydrolysis of wet LOXIL-treated, IL-treated, and native switchgrass was carried out as described in Example 2.
[0064] The 24-hour hydrolysis yields of glucose from glucan and xylose from xylan from treated and untreated switchgrass are shown in Table 7. Yields are reported as a percentage of monomeric sugars obtained from enzyme hydrolysis divided by the theoretical concentration of monomeric sugar based on the initial mass and composition of untreated biomass. Glucose and xylose yields for LOXIL-treated switchgrass were approximately 5 and 16 times greater than that of native switchgrass, respectively.
[0000]
TABLE 7
Twenty-four hour enzymatic hydrolysis yields of monomeric sugars
for treated and native switchgrass substrates. 10 mg/ml of treated
or native switchgrass samples were hydrolyzed at an enzyme loading
of 5.1 mg protein per gram of glucan. Anti-solvent for LOXIL-
treated and IL-treated switchgrass was ethanol.
% Glucose Yield
% Xylose Yield
Switchgrass Substrates
(Enhancement*)
(Enhancement*)
LOX (24 h at 25° C.),
54 d (>4)
32 d (16)
IL-treated (4 h at 50° C.)
IL-treated (4 h at 50° C.)
15 ± 1
4 ± 0
LOX (24 h at 25° C.)
29 ± 0
19 ± 0
Native
12 d
2 d
*Yield Enhancement is defined as the ratio of yield for treated biomass divided by that of untreated native biomass.
d Average of duplicates
Example 7
Enzyme Hydrolysis of Wet LOXIL-Treated Poplar with Lignin Oxidation at Room Temperature for 24 Hours, Using AHP Solution as the Oxidizing Solution, IL Treatment at 40° C. for 24 Hours with 5 wt % Solids, and Water as the Anti-Solvent
[0065] Poplar was incubated at 25° C. for 24 hours in an oxidizing solution comprised of a 10 wt % ratio of NaOH to biomass and a 12.5 wt % ratio of H 2 O 2 to biomass, as described in Example 2, to produce LOX poplar. For LOXIL-treated poplar, LOX samples were incubated in IL at 40° C. for 24 hours with 5 wt % biomass loading in IL, as described in Example 2. The anti-solvent water was used to displace IL and to produce LOXIL-treated poplar. Batch enzymatic hydrolysis of wet LOXIL-treated, IL-treated, and native poplar was carried out as described in Example 2.
[0066] The 24-hour hydrolysis yields of glucose from glucan and xylose from xylan for treated and untreated poplar are shown in Table 8. Yields are reported as a percentage of monomeric sugars obtained from enzyme hydrolysis divided by the theoretical concentration of monomeric sugar based on the initial mass and composition of untreated biomass. Glucose and xylose yields for LOXIL-treated poplar were at least 18 and 32 times greater than that of native poplar, respectively.
[0000]
TABLE 8
Twenty-four hour enzymatic hydrolysis yields of monomeric
sugars for treated and native poplar substrates. 10 mg/ml
of treated or native poplar samples were hydrolyzed at an
enzyme loading of 5.1 mg protein per gram of glucan. Anti-
solvent for LOXIL-treated and IL-treated poplar was water.
% Glucose Yield
% Xylose Yield
Poplar Substrates
(Enhancement*)
(Enhancement*)
LOX (24 h at 25° C.)
74 ± 2
(>18)
32 ± 2
(32)
IL-treated (24 h at 40° C.)
IL-treated (24 h at 40° C.)
24 d
(>6)
11 d
(13)
LOX (24 h at 25° C.)
13 ± 0
(>3)
19 ± 1
(19)
Native
4 ± 0
1 ± 0
*Yield Enhancement is defined as the ratio of yield for treated biomass divided by that of untreated native biomass.
d Average of duplicates
Example 8
Enzyme Hydrolysis of Wet LOXIL-Treated Poplar with Lignin Oxidation at Room Temperature for 24 Hours, Using AHP Solution as the Oxidizing Solution, IL Treatment at 30° C. for 24 Hours with 5 wt % Solids Loading, and Water as the Anti-Solvent
[0067] Poplar was incubated at 25° C. for 24 hours in an oxidizing solution comprised of a 10 wt % ratio of NaOH to biomass and a 12.5 wt % ratio of H 2 O 2 to biomass, as described in Example 2, to produce LOX poplar. For LOXIL-treated poplar, LOX samples were incubated in IL at 30° C. for 24 hours with 5 wt % biomass loading in IL, as described in Example 2. The anti-solvent water was used to displace IL and to produce LOXIL-treated poplar. Batch enzymatic hydrolysis of wet LOXIL-treated, wet IL-treated, and native poplar was carried out as described in Example 2.
[0068] The 24-hour hydrolysis yields of glucose from glucan and xylose from xylan for treated and untreated poplar are shown in Table 9. Yields are reported as a percentage of monomeric sugars obtained from enzyme hydrolysis divided by the theoretical concentration of monomeric sugar based on the initial mass and composition of untreated biomass. Glucose and xylose yields for LOXIL-treated poplar were at least 16 and 32 times greater than that of native poplar, respectively.
[0000]
TABLE 9
Twenty-four hour enzymatic hydrolysis yields of monomeric
sugars for treated and native poplar substrates. 10 mg/ml
of treated or native poplar samples were hydrolyzed at an
enzyme loading of 5.1 mg protein per gram of glucan. Anti-
solvent for LOXIL and IL-treated poplar was water.
% Glucose Yield
% Xylose Yield
Poplar Substrates
(Enhancement*)
(Enhancement*)
LOX (24 h at 25° C.),
65 ± 2
(>16)
32 ± 2
(32)
IL-treated (24h at 30° C.)
IL-treated (24 h at 30° C.)
13 d
(>3)
4 d
(4)
LOX (24 h at 25° C.)
13 ± 0
(>3)
19 ± 1
(19)
Native
4 ± 0
1 ± 0
*Yield Enhancement is defined as the ratio of yield for treated biomass divided by that of untreated biomass.
d Average of duplicates
Example 9
Enzyme Hydrolysis of LOXIL-Treated Poplar with Lignin Oxidation for 24 Hours, Using Potassium Peroxymonosulfate Triple Salt Solution as the Oxidizing Solution, IL Treatment at 75° C. for 4 Hours and 5 wt % Solids Loading, and Water as the Anti-Solvent
[0069] Poplar was incubated for 24 hours in an oxidizing solution comprised of 65 mM potassium peroxymonosulfate triple salt (2KHSO 5 .KHSO 4 .K 2 SO 4 , average molecular weight of 614.76 g/mol) in water. Water was added such that a 10% (w/v) biomass-to-liquid solution was obtained. After lignin oxidation, the liquid was removed from the poplar via filtration, producing LOX poplar. The LOX poplar was not further dried after filtration. For LOXIL-treated poplar, LOX samples were incubated in IL at 75° C. for 4 hours with 5 wt % biomass loading in IL, as described in Example 2. The anti-solvent water was used to displace IL and to produce LOXIL-treated poplar. Batch enzymatic hydrolysis of wet LOXIL-treated, IL-treated, and native poplar was carried out as described in Example 2.
[0070] The 24-hour hydrolysis yields of glucose from glucan and xylose from xylan for treated and untreated poplar are shown in Table 10. Yields are reported as a percentage of monomeric sugars obtained from enzyme hydrolysis divided by the theoretical concentration of monomeric sugars obtained from enzyme hydrolysis divided by the theoretical concentration of monomeric sugar based on the initial mass and composition of untreated biomass. Glucose and xylose yields for LOXIL-treated poplar were 18 and 52 times greater than that of native poplar, respectively.
[0000]
TABLE 10
Twenty-four hour enzymatic hydrolysis yields of monomeric
sugars for treated and native poplar substrates. 10 mg/ml
of treated or native poplar samples were hydrolyzed at an
enzyme loading of 5.1 mg protein per gram of glucan. Anti-
solvent for LOXIL-treated and IL-treated poplar was water.
% Glucose Yield
% Xylose Yield
Poplar Substrates
(Enhancement*)
(Enhancement*)
LOX (24 h at 40° C.),
72 ± 2
(18)
52 ± 5
(52)
IL-treated (4 h at 75° C.)
IL-treated (4 h at 75° C.)
45 ± 2
(>11)
29 ± 4
(29)
LOX (24 h at 40° C.)
4 s
(4)
2 s
(2)
Native
4 ± 0
1 ± 0
*Yield Enhancement is defined as the ratio of yield for treated biomass divided by that of untreated biomass.
d Average of duplicates
s Single measurement
Example 10
Enzyme Hydrolysis of LOXIL-Treated Poplar with Lignin Oxidation at 40° C. for 24 Hours, Using Ammonium Persulfate as the Oxidizing Solution, IL Treatment at 75° C. for 4 Hours and 5 wt % Solids Loading, and Water as the Anti-Solvent
[0071] Poplar was incubated at 40° C. for 24 hours in an oxidizing solution comprised of 0.34M ammonium persulfate, (NH 4 ) 2 S 2 O 8 , in water. Water was added such that a 10% (w/v) biomass-to-liquid solution was obtained. After lignin oxidation, the liquid was removed via filtration, producing LOX poplar. The LOX poplar was not further dried after filtration. For LOXIL-treated poplar, LOX samples were incubated in IL at 75° C. for 4 hours with 5 wt % biomass loading in IL, as described in Example 2. The anti-solvent water was used to displace IL and to produce LOXIL-treated poplar. Batch enzymatic hydrolysis was wet LOXIL-treated, IL-treated, and native poplar was carried out as described in Example 2.
[0072] The 24-hour hydrolysis yields of glucose from glucan and xylose from xylan for treated and untreated poplar are shown in Table 11. Yields are reported as a percentage of monomeric sugars obtained from enzyme hydrolysis divided by the theoretical concentration of monomeric sugar based on the initial mass and composition of untreated biomass. Glucose and xylose yields for LOXIL-treated poplar were 15 and 46 times greater than that of native poplar, respectively.
[0000]
TABLE 11
Twenty-four hour enzymatic hydrolysis yields of monomeric
sugars for treated and native poplar substrates. 10 mg/ml
of treated or native poplar samples were hydrolyzed at an
enzyme loading of 5.1 mg protein per gram of glucan. Anti-
solvent for LOXIL-treated and IL-treated poplar was water.
% Glucose Yield
% Xylose Yield
Poplar substrates
(Enhancement*)
(Enhancement*)
LOX (24 h at 40° C.),
60 s
(15)
46 s
(46)
IL-treated (4 h at 75° C.)
IL-treated (4 h at 75° C.)
45 ± 2
(>11)
29 ± 4
(29)
LOX (24 h at 40° C.)
4 s
(4)
2 s
(2)
Native
4 ± 0
1 ± 0
*Yield Enhancement is defined as the ratio of yield for treated biomass divided by that of untreated biomass.
d Average of duplicates
s Singlet
Example 11
Enzyme Hydrolysis of LOXIL-Treated Poplar with Lignin Oxidation at 25° C. for 6 Hours, Using AHP as the Oxidizing Solution, IL Treatment at 40° C. for 24 Hours and 5 wt % Solids Loading, and Water as the Anti-Solvent
[0073] Poplar was incubated at 25° C. for 6 hours in an alkaline solution comprised of a 10 wt % ratio of NaOH to biomass and a 12.5 wt % ratio of H 2 O 2 to biomass, as described in Example 2, to produce LOX poplar. For LOXIL-treated poplar, LOX samples were incubated in IL at 40° C. for 24 hours with 5 wt % biomass loading in IL, as described in Example 2. The anti-solvent water was used to displace IL and to produce LOXIL-treated poplar. Batch enzymatic hydrolysis of wet LOXIL-treated, wet IL-treated, and native poplar was carried out as described in Example 2.
[0074] The 24-hour hydrolysis yields of glucose from glucan and xylose from xylan for treated and untreated poplar are shown in Table 12. Yields are reported as a percentage of monomeric sugars obtained from enzyme hydrolysis divided by the theoretical concentration of monomeric sugar based on the initial mass and composition of untreated biomass. Enzymatic hydrolysis glucose and xylose yields for LOXIL-treated poplar were 18 and 34 times greater than that of native poplar, respectively.
[0000]
TABLE 12
Twenty-four hour enzymatic hydrolysis yields of monomeric
sugars for treated and native poplar substrates. 10 mg/ml
of treated or native poplar samples were hydrolyzed at an
enzyme loading of 5.1 mg protein per gram of glucan. Anti-
solvent for LOXIL and IL-treated poplar was water.
% Glucose Yield
% Xylose Yield
Poplar Substrates
(Enhancement*)
(Enhancement*)
LOX (6 h at 25° C.)
75 d
(>18)
34
(34)
IL-treated (24 h at 40° C.)
IL-treated (24 h at 40° C.)
24 d
(6)
11 d
(11)
LOX (6 h at 25° C.)
11 ± 0
(>2)
1 ± 0
(1)
Native
4 ± 0
1 ± 0
*Yield Enhancement is defined as the ratio of yield for treated biomass divided by that of untreated biomass.
d Average of duplicates
Example 12
Enzyme Hydrolysis of Wet LOXIL-Treated Poplar with Lignin Oxidation at Room Temperature for 6 Hours, Using AHP Solution as the Oxidizing Solution, IL Treatment at 30° C. for 24 Hours with 5 wt % Solids Loading, and Water as the Anti-Solvent
[0075] Poplar was incubated for 6 hours in an oxidizing solution comprised of a 10 wt % ratio of NaOH to biomass and a 12.5 wt % ratio of H 2 O 2 to biomass, as described in Example 2, to produce LOX poplar. For LOXIL-treated poplar, LOX samples were incubated in IL at 30° C. for 24 hours with 5 wt % biomass loading in IL, as described in Example 2. The anti-solvent water was used to displace IL and to produce LOXIL-treated poplar. Batch enzymatic hydrolysis of wet LOXIL-treated, wet IL-treated, and native poplar was carried out as described in Example 2.
[0076] The 24-hour hydrolysis yields of glucose from glucan and xylose from xylan for treated and untreated poplar are shown in Table 13. Yields are reported as a percentage of monomeric sugars obtained from enzyme hydrolysis divided by the theoretical concentration of monomeric sugar based on the initial mass and composition of untreated biomass. Enzymatic hydrolysis glucose and xylose yields for LOXIL-treated poplar were 16 and 31 times greater than that of native poplar, respectively.
[0000]
TABLE 13
Twenty-four hour enzymatic hydrolysis yields of monomeric
sugars for treated and native poplar substrates. 10 mg/ml
of treated or native poplar samples were hydrolyzed at an
enzyme loading of 5.1 mg protein per gram of glucan. Anti-
solvent for LOXIL-treated and IL-treated poplar was water.
% Glucose Yield
% Xylose Yield
Poplar Substrates
(Enhancement*)
(Enhancement*)
LOX (6 h at 25° C.)
66 d
(>16)
31
(31)
IL-treated (24 h at 30° C.)
IL-treated (24 h at 30° C.)
13 d
(6)
4 d
(11)
LOX (6 h at 25° C.)
11 ± 0
(>2)
1 ± 0
(1)
Native
4 ± 0
1 ± 0
*Yield Enhancement is defined as the ratio of yield for treated biomass divided by that of untreated biomass.
d Average of duplicates
Example 13
Enzyme Hydrolysis of Wet LOXIL-Treated Poplar with Lignin Oxidation at Room Temperature for 6 Hours, Using AHP Solution as the Oxidizing Solution, Wet IL Treatment at 75° C. for 4 Hours and 5 wt % Loading, and Water as the Anti-Solvent
[0077] Poplar was incubated for 6 hours in an oxidizing solution of a 10 wt % ratio of NaOH to biomass and a 12.5 wt % ratio of H 2 O 2 to biomass. Water was added to a final concentration of 10% (w/v) biomass solids in the liquid solution. After lignin oxidation, the liquid was removed from the sample through mechanical means such as filtration, producing wet LOX poplar. Without further drying, wet LOX poplar was then combined with EMim-OAc at a 5 wt % biomass-to-ionic-liquid ratio (based on dry weight) for incubation for 4 hours at 50° C. The anti-solvent for this example was water. Batch enzymatic hydrolysis of wet LOXIL-treated, wet IL-treated, and native poplar was carried out as described in Example 2.
[0078] The average and standard deviation of replicate samples of 24-hour hydrolysis yields of glucose from glucan and xylose from xylan from treated and untreated poplar are shown in Table 14. Yields are reported as a percentage of monomeric sugars obtained from enzyme hydrolysis divided by the theoretical concentration of monomeric sugar based on the initial mass and composition of untreated biomass. Enzymatic hydrolysis glucose and xylose yields for LOXIL-treated poplar were at least 18 and 52 times greater than that of native poplar, respectively.
[0000]
TABLE 14
Twenty-four hour enzymatic hydrolysis yields of monomeric
sugars for treated and native poplar substrates. 10 mg/ml
of treated or native poplar samples were hydrolyzed at an
enzyme loading of 5.1 mg protein per gram of glucan. Anti-
solvent for LOXIL and IL-treated poplar was water.
% Glucose Yield
% Xylose Yield
Poplar Substrates
(Enhancement*)
(Enhancement*)
LOX (6 h at 25° C.),
75 ± 1
(>18)
52 ± 5
(52)
IL-treated (4 h at 75° C.)
IL-treated (4 h at 75° C.)
45 ± 2
(>11)
29 ± 4
(29)
LOX (6 h at 25° C.)
11 ± 0
(>2)
1 ± 0
(1)
Native
4 ± 0
1 ± 0
[0079] Certain embodiments of the methods disclosed herein are defined in the above examples. It should be understood that these examples, while indicating particular embodiments of the invention, are given by way of illustration only. From the above discussion and these examples, one skilled in the art can ascertain the essential characteristics of this disclosure, and without departing from the spirit and scope thereof, can make various changes and modifications to adapt the compositions and methods described herein to various usages and conditions. Various changes may be made and equivalents may be substituted for elements thereof without departing from the essential scope of the disclosure. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the disclosure without departing from the essential scope thereof. | A method for pretreating lignocellulosic biomass having a lignin component, a hemicellulose component, and a cellulose component, for conversion to sugar is disclosed. Also disclosed is the pretreated lignocellulosic biomass resulting from the method. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
Not applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not applicable.
BACKGROUND OF THE INVENTION
1. Field of the Invention
Embodiments disclosed herein relate to apparatuses and methods used in well operations. More specifically, embodiments disclosed herein relate to slip assemblies used in well operations. More specifically still, embodiments disclosed herein relate to cageless slip assemblies used in well operations.
2. Background Art
This section of this document introduces various information from the art that may be related to or provide context for some aspects of the technique described herein and/or claimed below. It provides background information to facilitate a better understanding of that which is disclosed herein. This is a discussion of “related” art. That such art is related in no way implies that it is also “prior” art. The related art may or may not be prior art. The discussion in this section is to be read in this light, and not as admissions of prior art.
Slip assemblies are used in well completion operations to secure downhole tools in the well bore. For examples, slip assemblies may be run downhole on a tubular string and then radially expanded to secure packers, anchors, plugs, or other downhole tools to the sidewall of a well or well casing.
Typical slip assemblies include a cage or springs that prevent the slips from contacting the annular area, thereby allowing the slip assemblies, to be deployed to a specified depth without becoming stuck or prematurely setting. Once at the specified depth, the slips are released from the case or spring system using mechanical or hydraulic, systems, thereby allowing the slips to radially expand into contact with the well or casing wall. Such cage and spring systems occupy annular space on the tool, thereby reducing the cross-sectional area through which a tool, such as a packer, anchor, or plug may be run. However, the cage and/or spring systems are required to prevent premature actuation of the tool.
Accordingly, there exists a need for a slip assembly that may be run downhole without the requirement of a cage or spring system to prevent premature tool actuation.
The present invention is directed to resolving, or at least reducing, one or all of the problems mentioned above.
SUMMARY OF THE DISCLOSURE
In various aspects and embodiments, the disclosure herein relates to methods and apparatus associated with a slip assembly.
In a first aspect, a slip assembly comprises a plurality of slip segments, wherein each of the plurality of slip segments and a bonding substrate. The slip segments comprise: a first end having a plurality of teeth; a second end opposite the first end; and a transition section between the first end and the second end. The bonding substrate is disposed within the transition sections.
In a second aspect, a method of manufacturing a slip assembly comprises forming a plurality of teeth on at least one of a first end and a second end of a tubular; forming a recess on the tubular, wherein the recess is formed between the first and second ends; milling the tubular to form a plurality of slip segments; and bonding the plurality of slip segments to form an assembled slip assembly.
In a third aspect, a method of deploying a downhole tool comprises: running the downhole tool comprising a slip assembly into a well, wherein the slip assembly comprises a plurality of bonded slip segments; breaking the bonds of the slip segments; radially expanding the plurality of slip segments; and engaging a wall of the well with the slip assembly.
In a fourth aspect, a method of manufacturing a slip assembly comprises, the method comprising: forming a plurality of slip segments, wherein the plurality of slip segments comprise a first end, a second end, and a transition between the first and second ends, and wherein at least one, of the first and second ends have a plurality of teeth; and bonding the plurality of slip segments to form an assembled slip assembly.
The above presents a simplified summary of the invention in order to provide a basic understanding of some aspects of the invention. This summary is not an exhaustive overview of the invention. It is not intended to identify key or critical elements of the invention or to delineate the scope of the invention. Its sole purpose is to present some concepts in a simplified form as a prelude to the more detailed description that is discussed later.
BRIEF DESCRIPTION OF DRAWINGS
The invention may be understood by reference to the following description taken in conjunction with the accompanying drawings, in which like reference numerals identify like elements, and in which:
FIG. 1 is a partial cross-sectional view of a slip assembly according to embodiments of the present disclosure.
FIG. 2 is a perspective view of a slip assembly according to embodiments of the present disclosure.
FIG. 3 is a cross-sectional view of a slip assembly according to embodiments of the present disclosure.
FIG. 4 is a perspective view of a slip assembly according to embodiments of the present disclosure.
FIG. 5 is a flow chart diagram of a method of forming a slip assembly according to embodiments of the present disclosure.
FIG. 6 is a flow chart diagram of a method for using a slip assembly according to embodiments of the present disclosure.
While the invention is susceptible to various modifications and alternative forms, the drawings illustrate specific embodiments herein described in detail by way of example. It should be understood, however, that the description herein of specific embodiments is not intended to limit the invention to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.
DETAILED DESCRIPTION
Illustrative embodiments of the invention are described below. In the interest of clarity, not all features of an actual implementation are described in this specification. It will of course be appreciated that in the development of any such actual embodiment, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which will vary from one implementation to another. Moreover, it will be appreciated that such a development effort, even if complex and time-consuming, would be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure.
In general, embodiments disclosed herein relate to apparatuses and methods used in well operations. More specifically, embodiments disclosed herein relate to slip assemblies used in well operations. More specifically still, embodiments disclosed herein relate to cageless slip assemblies used in well operations.
As explained above, traditional slip assemblies used in downhole tools, such as packers, anchors, plugs, and the like, require use of a cage or spring system to retain slips during downhole deployment. The cage or spring systems take up valuable annular space, as the cage and/or spring systems may extend radially from the tool body. Because the cage and/or spring systems may have an outside diameter that is greater than the slips or other tool portions, the cage and/or spring systems may reduce the cross-sectional area through which the downhole tool may be deployed.
Embodiments disclosed herein provide slip assemblies that do not require the use of a cage or spring system. Rather than rely on cage or spring systems to prevent the premature actuation of the slip assemblies, the slips are divided then bonded in place. The bonds are broken in a controlled fashion once the tool has reached the desired depth.
Referring to FIG. 1 , a partial cross-sectional view of a slip assembly 100 according to embodiments of the present disclosure is shown. In this embodiment, slip assembly 100 has a first end 110 and a second end 120 . As illustrated, the first end 110 and the second end 120 each have a plurality of teeth 130 . The plurality of teeth 130 extend radially from the slip assembly 100 , and are configured to engage a well or casing wall after actuation. In certain embodiments, only one of the first end 110 or second end 120 may include teeth 130 . In such an embodiment, actuation of the slip assembly may thus only cause the teeth 130 of either first end 110 or second 120 to engage a well wall.
Slip assembly 100 further includes a transition section 140 located between first end 110 and second end 120 . Transition section 140 is recessed, such that the outer diameter of transition section 140 may be less than the outer diameter of first end 110 and second end 120 . In embodiments where only one of first end 110 and second end 120 have teeth 130 , the transition section may have an outer diameter that is less than the end 110 / 120 that has teeth 130 . The transition section 140 in this embodiment has a constant outside diameter, however, in alternate embodiments, the transition section 140 may have grooves or other geometric profiles.
Slip assembly 100 is divided into a plurality of slip segments 150 a , 150 b , and 105 c . The plurality of slip segments 150 a , 150 b , and 150 c are milled from a tubular material, so the plurality of slip segments 150 a , 150 b , and 150 c corresponded to one another. The manufacturing process for slip assembly 100 is described in detail below. Depending on the requirements of the operation, the number of slip segments 150 into which slip assembly 100 is divided may vary. For example, in certain embodiments, the slip assembly 100 may be divided into two, three, four, or more slip segments 150 . In such embodiments, the segments may be 180° segments, 120° segments, or 90° segments, respectively. However, in other embodiments, such as when smaller diameter casing is used, e.g., 3-6 inch casing, six to eight segments may be preferable. In other embodiments, such as when larger diameter casing is used, e.g., 12-36 inch casing, as may be used in offshore wells, the slip assembly 100 may be divided into 36 or more segments. The number of slip segments 150 that slip assembly 100 is divided into may be as many as is practical to occupy the full 360° circumference of the slip assembly 100 . The same is generally true for different diameters of so-called “open hole” wells (with no casing).
Referring to FIG. 2 , a perspective view of a slip assembly 200 according to embodiments of the present disclosure is shown. FIG. 2 is a perspective view of the slip assembly 200 of FIG. 1 , i.e., slip assembly 100 , and illustrates the slip assembly 200 prior to connecting individual slip segments 250 with a bonding substrate. Slip assembly 200 has a first end 210 and a second end 220 . As illustrated, the first end 210 and the second end 220 each have a plurality of teeth 230 . Slip assembly 200 further includes a transition section 240 located between first end 210 and second end 220 .
FIG. 2 illustrates a slip assembly 200 that has six slip segments 250 a - f . Each slip segment 250 a - f is 60°, so that when assembled, the slip segments 250 a - f form a complete 360 circumference. As may be readily seen in FIG. 2 , transition 240 extends around the entire circumference of slip assembly 200 ; however, in alternate embodiments, transition 240 may not be continuous around the entire circumference. For example, transition 240 may extend for a limited portion of the circumference, such as around the portions of slip assembly 200 where slip segments 250 a - f are divided.
Referring to FIG. 3 , a cross-sectional view of a slip assembly 300 according to embodiments of the present disclosure is shown. FIG. 3 illustrates slip assembly 300 after individual slip segments 350 have been bonded. Slip assembly 300 has a first end 310 and a second end 320 . As illustrated, the first end 310 and the second end 320 each have a plurality of teeth 330 . Slip assembly 300 further includes a transition section 340 located between first end 310 and second end 320 .
Slip assembly 300 further includes a bonding substrate 360 disposed in transition 340 . The bonding substrate 360 may include various substances capable of bonding slip segments 350 together. Examples of bonding substrates 360 may include various elastomers and/or polymers, including polymer resins and fiber composites. The elastomer and/or polymers may be applied to transition 340 to create a laminated tubular section of slip assembly 300 .
Along the internal diameter of slip assembly 300 , a secondary bonding substrate 370 may be applied to hold slip segments 350 in place during the process of connecting/bonding the individual slip segments 350 . In alternate embodiments, secondary bonding substrate 370 may be used in place of bonding substrate 360 . Depending on the requirements of the slip assembly 300 , bonding substrate 360 and secondary bonding substrate 370 may be formed of the same material, or alternatively, may be formed from different materials. For example, bonding substrate 360 may be an elastomer bond, while secondary bonding substrate 370 may be a polymer bond. Either may be reinforced with fiber in a matrix composite.
Referring to FIG. 4 , a perspective view of a slip assembly 400 according to embodiments of the present disclosure is shown. FIG. 4 illustrates slip assembly 400 in an assembled condition, wherein individual slip segments 450 have been connected through the use of a bonding substrate 460 .
Slip assembly 400 has a first end 410 and a second end 420 . As illustrated, the first end 410 and the second end 420 each have a plurality of teeth 430 . Slip assembly 400 further includes a bonding substrate 460 located between first end 410 and second end 420 . FIG. 4 further illustrates slip assembly 400 that has six slip segments 450 a - f . Each slip segment 250 a - f is 60°, so that when assembled, the slip segments 450 a - f form a complete 360 circumference.
In this embodiment, bonding substrate 460 is disposed in the transition portion (not shown) around the entire circumference of slip assembly 400 . Thus, individual slip segments 450 a - f are held in place so as to form slip assembly 400 . Additionally, secondary bonding substrate 470 is disposed along the inner diameter of slip assembly 400 , thereby providing an additional connection between the slip segments 450 a - f.
Referring to FIG. 5 , a flow chart diagram of a method for manufacturing a slip assembly according to embodiments of the present disclosure is shown. In manufacturing a slip assembly, a tubular portion is selected for a particular application. Examples of types of tubular that may be used include metallic tubulars, such as steel or other metals, as well as non-metallic tubulars, such as fiberglass, carbon, or ceramics.
In manufacturing the slip assembly, a first end of the tubular is formed ( 500 ) to include a plurality of teeth. The first end may be formed by, for example, milling a portion of the tubular to a selected slip profile. Similarly, a second end of the tubular is formed 510 . The second end of the tubular may be formed to include teeth, or may be formed to match an alternative slip profile. Those of ordinary skill in the art will appreciate that the plurality of teeth may be formed to include conventional tooth patterns as known in the oilfield industry.
In addition to forming ( 500 and 510 ) the first and second ends, a recess is formed ( 520 ) on the tubular between the first and second ends. The depth of the recess may be selected based on the requirements of a particular slip assembly or based on operational constraints. For example, the depth of the recess may be determined based on a volume of bonding substrate that is required to hold individual slip segments in place.
The method further includes milling ( 530 ) the tubular to form a plurality of slip segments. During the slip segment milling ( 530 ), the slip assembly may be divided into individual slip segments by milling linearly, or longitudinally, along the length of the tubular. As discussed above, the number of slip segments created may vary based on the requirements of the downhole operation and/or the specifics of the well, such as the diameter of the well bore or casing. In certain embodiments, an inner diameter ring may be disposed in the tubular prior to milling ( 530 ), such that the individual slip segments are held in place throughout the remainder of the manufacturing process. If used, an inner diameter ring may be removed any time after the slip segments are bonded.
After the slip segments are milled ( 530 ), the plurality of slip segments may be bonded ( 540 ) to form an assembled slip assembly. The bonding process may include applying an elastomer or polymer substrate to the transition or recessed section of the slip assembly. In certain embodiments, the bonding ( 540 ) may further include applying a secondary substrate along the inner diameter of the slip assembly, such as along the area in which an inner diameter ring was previously disposed.
After the slip assembly is assembled, the slip assembly may be disposed along a downhole tubular string for disposition into a well. Each slip segment has a load bearing that contacts the mandrel preventing the slip from moving upward/downward into the slip cones and expanding into the well bore or casing. The only way that the slip can be expanded is to have the slip cone hydraulically or mechanically pushed into the cageless slip causing the slip to expand over the load bearing and outward into the well bore or casing.
The methods of manufacturing described herein are by way of example and illustration particular methods by which slip assemblies according to embodiments of the present disclosure may be formed. In alternative embodiments, additional steps may be undertaken or steps may be performed in different orders than expressly described herein. For example, the order that individual portions of the tubular are milled may vary and still be within the scope of the present disclosure.
Alternate methods for manufacturing a slip assembly according to embodiments of the present disclosure may be used. In these embodiments, rather than form a plurality of teeth along a preformed tubular, individual slip segments are formed. The individual slip segments may be formed in a variety of ways, including, for example, casting or molding the individual slip segments. In such an embodiment, a metal or composite may be introduced into a preformed mold, allowed to set, and then the resultant product removed from the mold.
Depending on the forming technique, the casting or molding material may be in liquid or solid state during introduction to the mold, and thus the introduction of the material into the mold may vary depending on the specific properties of the materials. Additionally, the types of materials used may influence the way in which the materials set or cure. In certain embodiments, the materials may be introduced after heating, and thus cooling of the materials in the mold allows the materials to set or cure. In alternative embodiments, such as with the use of thermosetting materials, the materials may be introduced to the mold, heated to a specific temperature, and then allowed to cool, thereby setting or curing the materials.
The mold may include any of the various design features for the slip segments described above. For example, the mold may include a slip segment having first and second ends with a transition section therebetween, wherein at least one of the ends includes a plurality of teeth. In certain embodiments, the mold may include first and second ends with a transition section therebetween, wherein both the first and second ends have a plurality of teeth.
After the slip segments have been formed, by setting or curing in the molds, the slip segments are removed from the molds. The individual slip segments may then be bonded together to form a complete assembled slip assembly. The number of slip segments used in forming the assembled slip assembly may vary according to the requirements of the completion operation as described above. In bonding the slip segments, the individual slip segments may be wrapped around a material tube, such as a metal or composite tubular, and bonded together using a bonding substrate, such as a polymer or elastomeric material. After the bonding substrate has cured, the material tube may be removed. The bonding substrate thus holds the individual slip segments together as an assembled slip assembly.
In certain embodiments a bonding substrate may alternatively be applied along the inner diameter of the slip segments. In such an embodiment, rather than wrapping the slip segments around a material tube, the slip segments may be held in place from either end of the slip segments or by compressing the slip segments into place along the outer diameter of the slip segments. As explained above, in certain embodiments, a bonding substrate may be applied to both the outer diameter and the inner diameter of the slip segments when forming an assembled slip assembly.
The types of composites used in manufacturing the slip assemblies described above may vary based on specific operational requirements. Examples of composite materials that may be used include carbon fiber, ceramics embedded in metal matrices, carbon/carbon materials, metal matrix composites, polymer composites, and the like. Particular resins used in either the composite materials used to form the slip segments or the bonding substrate may also vary depending on operational requirements, but may include, for example, various epoxy and epoxy derivatives, polyesters, vinlyesters, and the like. Those of ordinary skill in the art will appreciate that the aforementioned examples of composite materials and resins are not meant to be exhaustive and are not introduced as a specific limitation of the present disclosure. Rather, the above listed materials are illustrative of types of materials that may be used in forming components of the present disclosure.
Referring to FIG. 6 , a flow chart diagram of a method for using a slip assembly according to embodiments of the present disclosure is shown. During use of the slip assembly, initially, the slip assembly having a plurality of bonded slip segments is run ( 600 ) downhole. The slip assembly is lowered to a desired depth within the well, at which point the bonds holding the slip assembly segments are broken ( 610 ). The method for breaking the bonds may vary depending on the specific application for the slip assembly. For example, in certain embodiments, a hydraulic or mechanical force may be applied to the slip assembly that causes the slip segments to radially expand ( 620 ), thereby breaking/fracturing ( 610 ) the bonding substrate. In certain embodiments, the slip assembly may be self-setting. In such an embodiment, as the tool having the slip assembly is disposed into place within the well, the slip assembly self actuates. Depending on the particular embodiment in which the slip assembly is used, a separate setting tool may be disposed on the downhole tubular string; however, in certain applications, the setting tool may be an integral component of the particular tool in which the slip assembly is used.
As the slip segments radially expand ( 620 ), the teeth of the slip assembly engage ( 630 ) the wall of the well or casing, thereby locking a downhole tool in place. Those of ordinary skill in the art will appreciate that, as used herein, the wall of the well corresponds to any wall tubular, substrate, casing, or the like, with which the slip assembly may engage ( 630 ).
Advantageously, embodiments of the present disclosure may provide for slip assemblies that do not require the use of a cage or spring system. Because the slip assembly does not have a cage or spring system, the slip assembly provides greater radial slip extension, thereby allowing for use in larger inner diameter casing strings.
Additionally, downhole tools, such as packers, anchors, plugs, and the like that include such a slip assembly, may have a smaller outer diameter, which can be run in broader ranges of casing diameters. Thus, a single size tool may advantageously be used in a variety of applications.
Also advantageously, stronger tubular materials, such as steel may be used in place of low tensile ductile irons, which are used in certain applications, because the slip assembly is segmented prior to disposition downhole. Tools formed using low tensile ductile irons tend to fracture or prematurely actuate, thus, the slip assembly of the present disclosure may advantageously prevent tool damage, as well as premature actuation.
While the present disclosure has been described with respect to a limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciate that other embodiments may be devised which do not depart from the scope of the disclosure as described herein. Accordingly, the scope of the disclosure should be limited only by the attached claims. | Methods and apparatus associated with a slip assembly. The slip assembly comprises a plurality of slip segments, wherein each of the plurality of slip segments and a bonding substrate. The slip segments comprise: a first end having a plurality of teeth; a second end opposite the first end; and a transition section between the first end and the second end. The bonding substrate is disposed within the transition sections. | 4 |
BACKGROUND OF THE INVENTION
This invention relates to a sealing assembly for a blending apparatus. More particularly, it relates to a sealing arrangement for a vacuum source connected to a blender wherein the blender is rotated and the vacuum source can be connected in a manner such that the risk of contaminants from outside atmosphere or the sealing assembly itself is substantially reduced.
There exists a problem in making connections to a blending apparatus wherein the contents of the blender are held under a vacuum during the mixing operation. In a conventional blender of this type, a vacuum line is usually placed inside a trunion and ultimately interconnected with the inside of the blender. Some means of sealing the inner vacuum line from outside atmosphere must be accomplished as the trunion rotates over the inner vacuum line. In U.S. Pat. No. 3,313,550, a stuffing box is provided for a mixing apparatus and is in the form of a split seal arrangement to be placed around an agitator shaft. The prior art does not provide a solution to the problem of providing a sealing arrangement for a blending apparatus wherein the contents are placed under a vacuum and a sealing assembly is arranged such that the probability of contaminants entering into the blender are reduced to a minimum.
It is an advantage of the present invention to provide a novel sealing assembly for a blending apparatus. Other advantages are a seal arrangement for a blending apparatus wherein a vacuum connection is made and the sealing assembly is provided separately from the blender; a vacuum line is integrally connected to the blending device and is sealed inside of the separate housing through which the vacuum connection to the vacuum source is made; a sealing assembly for a rotating blending apparatus wherein the sealing means for a vacuum connection is made in such a manner that it can be easily disconnected for maintenance purposes; a sealing assembly for a blender with a vacuum connection wherein the sealing assembly can be mounted to a standard blending apparatus with a vacuum connection.
SUMMARY OF THE INVENTION
The foregoing objects are accomplished and the shortcomings of the prior art overcome by the present sealing assembly for a blending apparatus wherein a vacuum conduit is in fluid communication with the inside of the mixer. The blender will have the usual end wall with means to rotatably support the blender which will include a trunion. Passage means extend through the trunion and are in fluid communication with the inside of the blender. The passage means includes an extending conduit member integrally secured to the blender and rotatable therewith. A sealing housing member is separately supported from the blender and is adapted to receive an end portion of the conduit member. A vacuum conduit is also in fluid-tight communication with the inside of the housing and means are provided to seal the conduit member inside the housing member. The sealing housing member includes a main body portion with at least one opposing end plate removably secured to it. The preferred means of sealing the tubular member inside the housing member includes spaced apart bushing members with sealing rings disposed therebetween. Grease fitments are also provided for purposes of lubricating the bushings.
BRIEF DESCRIPTION OF THE DRAWING
A better understanding of the sealing assembly will be afforded by reference to the drawing wherein:
FIG. 1 is a perspective view illustrating a blending apparatus with means for supporting and driving the blender and the novel vacuum sealing assembly therefor.
FIG. 2 is an enlarged view in vertical section illustrating the sealing assembly for the blender shown in FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The sealing assembly generally 10 is shown in FIGS. 1 and 2 in combination with a blending apparatus 12 which is rotatably supported on supports 16 and 17 by means of trunions 11 and 13 to which are secured guide rollers 15 and 20 rotatably supported on support rollers 33 and 28. Secured to the end of trunion 13 is a bull gear 24 which is driven by drive gear 23 of motor 22. A support platform 18 provides the necessary placement of motor 22. Extending through trunion 11 and in communication with the inside of mixer 12 is a pipe member 40 which terminates in a filter 44. Pipe 40 is attached to a conduit member 14 by engagement of a flange 37 secured to flange 36 connected to pipe 40. The sealing assembly 10 is mounted on a vertical support 35 which in turn extends from support platform 34 attached to support 16. A vacuum pipe 67 is also interconnected to sealing assembly 10 opposite conduit member 14.
Referring to FIG. 2, it will be seen that the sealing assembly includes a cylindrical housing 50 to which are attached end plates 52 and 53 secured through cap screws 55. Conduit member 14 will be integrally connected to flange 36 by means of weldment 39. The opposite end of conduit member 14 will be sealed and positioned in housing 50 through oppositely placed bushings 57 and 58 having grease grooves 64 communicating with grease passage 63 in housing 50. Grease fittings 62 of the Zerk type are placed in communication with the grease passages 63. Disposed between bushings 57 and 58 are packing rings 60 which generally are of the inner fitting V-shaped configuration except for those portions of the packing rings which contact bushings 57 and 58 which are straight edged. It will be noted that bushings 57 and 58 with the packing rings 60 placed therebetween are suitably held in housing 50 by abutment against end wall 47 of housing 50 and end wall 48 of end plate 52. Conduit member 14 will have its end portion terminate a short distance from the end of end plate 53. Secured to end plate 53 in a fixed manner is vacuum pipe 67 which is fixed thereto through weldment 68 and is spaced from conduit member 14.
OPERATION
A better understanding of the advantages of sealing assembly 10 will be had by a description of its assembly and operation. Blender 12 is of a standard variety known in the trade as a twin shell blender/dryer and is manufactured by the PattersonKelly Company of East Stroudsburg, Pennsylvania. In this instance it has a capacity of forty cubic feet. The drive and support mechanisms are indicated merely for illustration purposes as these could take the form of a variety of mechanisms. The essential component and typical vacuum connection to inside the blender 12 is pipe member 40 which is integrally connected and fixed to trunion 11 and communicating with the inside of the blender 12. This connection can be made to the standard blender by merely supplying flanges 36 and 37. Conduit member 14 will be placed inside cylindrical housing 50 with bushing 57, packing rings 60 and bushing 58 placed therein and over tubular member 14 in the indicated manner. End plate 52 will then be attached to housing 50 by cap screws 55 to secure the bushings and packing therein. At the opposite end, vacuum pipe 67 will be attached to cylindrical housing 50 by the securing of cap screws 55.
A vacuum source of 28-29 inches of mercury will be connected to vacuum pipe 67 and will be used for drying purposes. Blender 12 will be rotated through the driving engagement of drive gear 23 and bull gear 24. It should be appreciated that conduit member 14 will also rotate with blender 12 as it is directly fixed to pipe member 40 which in turn is secured to blender 12 for rotation therewith. By having the conduit tubular member 14 sealed in a separate housing 50 it can be appreciated that any contamination from the outside atmosphere and into the blender is extremely remote as none of the packing rings 60 or the bushings 57 and 58 are exposed to the outside atmosphere. Instead, they are housed inside housing 50 and sealed at opposing ends through end plates 52 and 53. Although the sealing assembly 10 provides a separate sealing assembly for a rotating tubular conduit which is in fluid communication with the inside of a blender and a vacuum source, it is easily disassembled for maintenance purposes by merely removing one or two end plates.
The preferred material for fabricating housing 50 is stainless steel and the dimensions are 41/2 inches for the outside diameter and the length. The bore for the packing bushings 57 and 58 is 27/8 inches for the internal diameter and 35/8 inches in depth. The end plates 52 and 53 have an outside diameter of 41/2 inches and are 1/2 inch in width.
In the previous description of the sealing assembly 10 it should be appreciated that the illustration of a blending apparatus of a particular type is intended for illustration purposes only. Any type of a rotatable blending-mixing unit would be operable with sealing assembly 10. It could include an intensifier mixer bar and the housing can be of various geometric configurations. A heating jacket can also be utilized in conjunction with the blender to aid in drying the contents. While a vacuum conduit is connected with the blender any fluid connection would be operable and the same advantages obtained. Further, while a particular bushing and sealing ring arrangement has been described for use in the sealing arrangement, any type of bushings whether of the lubricated or self-lubricating type and any number of sealing rings could be utilized and still accomplish the advantages of this invention.
It will thus be seen that through the present invention there is now provided a novel sealing arrangement for a rotatable blender having a fluid connection which will substantially reduce any problems of contaminants coming in contact with the inside of the blender. The sealing arrangement is placed separately from the blender and permits a vacuum connecting tube to rotate inside the sealing arrangement so as not to expose any of the packing or bushing members to outside atmosphere. At the same time, the sealing arrangement is easily disassembled for maintenance purposes and can be easily lubricated for low maintenance problems.
The foregoing invention can now be practiced by those skilled in the art. Such skilled persons will know that the invention is not necesarily restricted to the particular embodiments presented therein. The scope of the invention is to be defined by the terms of the following claims as given meaning by the preceding description. | A sealing assembly for a vacuum connection to a mixing apparatus so that the contents of the mixing apparatus are held under a vacuum during blending and the introduction of particulate matter is substantially reduced. The sealing assembly for the vacuum conduit is provided by means of a separate housing. A vacuum conduit is integrally attached to and rotates with the blender and an end portion of the conduit is sealed by means of bushings and packing in the assembly housing. The sealing assembly can be easily disconnected for maintenance purposes. | 8 |
[0001] The invention is based on a priority application EP 01 440 41 2.3 which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to a diplexer, particularly for use in microwave devices, comprising a low-pass filter and a high-pass filter, both having inductors and capacitors.
[0003] Generally, a diplexer is a three-port frequency-dependent device that may be used for separating or combining signals. The diplexer comprises a low-pass filter for extracting signals in a low frequency band and a high-pass filter for extracting signals in a high frequency band. Both, the low-pass filter and the high-pass filter are designed as passive units using capacitors and inductors for realising the mentioned functions.
[0004] A diplexer as mentioned above is for example known from U.S. Pat. No. 5,793,265. This diplexer also comprises a high-pass filter and a low-pass filter and serves the function of separating an incoming television signal from an incoming telephony signal, so that each of these signals can be processed by separate receivers when in a private home. Each of the filters is constructed in the form of a ladder network having series branches and parallel branches. In the high-pass filter, the series branches comprise capacitors and the parallel branches comprise inductors, with one of the parallel branches having a series inductor-capacitor circuit. In the low-pass filter, the series branches comprise inductors and the parallel branches comprise capacitors, one of the parallel branches having an inductor-capacitor series circuit.
[0005] In this document, it is proposed that all of the inductors of both filters be constructed as toroids. However, the problem is that these passive components have a physical size which makes it difficult to further minimize the diplexer. Moreover, the inductors have a bad quality factor in a frequency range above 1 GHz.
[0006] It has also turned out that using active filters instead of the passive filters shown for example in the above-mentioned prior art document is not an appropriate approach to the mentioned problem due to the relatively poor characteristics of such active filters. These characteristics make them insufficient for use in diplexers.
[0007] In view of the above, it is the object of the present invention to provide for a diplexer as mentioned in the outset which overcomes the problems mentioned above. Particularly, it is an object of the present invention to provide for a diplexer having a compact design, a high quality factor and stability, and being less expensive than prior art diplexers.
SUMMARY OF THE INVENTION
[0008] This object is solved by a diplexer particularly for use in microwave devices, comprising a low-pass filter and a high-pass filter, both having inductors and capacitors, wherein at least one inductor of each of said filters is provided as an active inductor.
[0009] That means in other words that spiral inductors, like toroids, are replaced with active components being constituted by capacitors, resistors and transistors and having the electrical characteristic of an inductor. The advantage of the diplexer according to the present invention is a substantial reduction of size since an active inductor builds smaller than a corresponding spiral inductor. Preferably, a reduction of about 90% may be achieved.
[0010] A further advantage of the diplexer according to the present invention is a cost reduction of the diplexer due to smaller packaging. Hence, the diplexer according to the present invention is less expensive compared to prior art diplexers.
[0011] A further advantage of the diplexer according to the present invention is an approvement of the quality factor and the stability.
[0012] The diplexer according to the present invention may be designed using GaAs technology. However, it is preferred to implement the diplexer using SiGe technology since the consumption of the diplexer is lower.
[0013] In a preferred embodiment, said active inductor having an input and an output terminal, said terminals being connected by a first branch comprising a first resistor, a first capacitor, a drain-source path of a first transistor and a second capacitor; a second branch comprising a gate-source path of a second transistor, a source-gate path of a third transistor, a third capacitor, a gate-source path of said first transistor and said second capacitor; a third branch comprising a gate-drain path of said second transistor, a fourth capacitor and a second resistor; a fourth branch comprising said gate-source path of said second transistor, a source-gate path of said third transistor, a fifth capacitor and said second resistor; and a fifth branch comprising said gate-source path of said second transistor, said source-drain path of said third transistor, a sixth capacitor and said second resistor.
[0014] This design has turned out as advantageous in view of its electrical characteristics. However, it is to be understood that other designs may be possible and the present invention is not limited thereto.
[0015] In a further embodiment, the low-pass filter comprises series and parallel branches, the series branches having inductor elements and active inductors alternately arranged, and the parallel branches having inductor elements and capacitor elements serially connected. Preferably, said high-pass filter comprises series and parallel branches, the series branches having capacitor elements, and the parallel branches having either inductor elements or active inductors, and capacitor elements serially connected.
[0016] It is to be understood that other inductor elements of the low-pass and high-pass filters may be replaced with active inductors.
[0017] Further features and advantages can be taken from the following description and the enclosed drawings.
[0018] It is to be understood that the features mentioned above and those yet to be explained below can be used not only in the respective combinations indicated, but also in other combinations or in isolation, without leaving the scope of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] An embodiment of the invention is shown in the drawings and will be explained in more detail in the description below with reference to same. In the drawings:
[0020] [0020]FIG. 1 is a schematic block diagram of a diplexer;
[0021] [0021]FIG. 2 is a schematic diagram of a low-pass filter having active inductors;
[0022] [0022]FIG. 3 is a schematic diagram of a high-pass filter having active inductors; and
[0023] [0023]FIG. 4 is a schematic diagram of a preferred design of an active inductor used in the low-pass and high-pass filters shown in FIGS. 2 and 3.
DETAILED DESCRIPTION OF THE INVENTION
[0024] In FIG. 1, a diplexer is shown and indicated with reference number 10 . The diplexer has three terminals 12 , 14 , 16 , two of which 12 , 14 serving as input terminals and the other terminal 16 serving as an output terminal in one operating mode. In a second operating mode, the function of the terminals is reversed, i.e. terminal 16 serves as input terminal and the other two terminals 12 , 14 serve as output terminals.
[0025] The diplexer 10 comprises a low-pass filter 20 and a high-pass filter 40 . The low-pass filter is coupled between the terminal 12 and the terminal 16 , whereas the high-pass filter 40 is coupled between the terminal 14 and the common terminal 16 .
[0026] In a first operating mode, the function of this diplexer is to combine two signals supplied to the terminals 12 and 14 and carrying information in a low frequency band and a high frequency band, respectively, to one signal carrying both information. This combined signal is supplied to terminal 16 .
[0027] In a second operating mode, the function is reversed. I.e., a common signal carrying both information in a low and a high frequency band is separated by the low-pass filter 20 and the high-pass filter 40 in a first signal carrying the information in the low frequency band and a second signal carrying the information in the high frequency band, respectively. The first signal is supplied to terminal 12 , while the second signal is supplied to terminal 14 .
[0028] The field of application of such diplexers is broad. For example, diplexers are used in current dual-band mobile telephone devices in order to separate the frequency ranges 880 MHz-960 MHz and 1710 MHz-1880 MHz. However, it is to be understood that the present diplexer is not limited to this application.
[0029] Referring to FIG. 2, the structure of the low-pass filter 20 is shown. The low-pass filter 20 is constructed as a four stage ladder network, wherein the first stage comprises an inductor 21 . 1 and an inductor 23 . 1 connected in series with a capacitor 25 . 1 . The second, third and fourth stages are constructed similarly to the first stage and also comprise an inductor 21 and an inductor 23 connected in series with a capacitor 25 (the stage number follows the reference number delimited by 11 . 11 ). The series circuits of inductors 23 and capacitors 25 constitute parallel branches of the ladder network, and the inductors 21 . 1 - 21 . 4 constitute series branches of the ladder network. The low-pass filter 20 is terminated with a further inductor 27 coupling an output terminal 17 of the low-pass filter 20 with the common node of the series branch and the parallel branch of the fourth stage of the ladder network.
[0030] In FIG. 2, the inductors 21 . 2 and 21 . 4 of the series branch of the second stage and the fourth stage, respectively, are provided as active inductors 30 . The design of the active inductor will be described in detail below with reference to FIG. 4. The remaining inductors 21 . 1 , 21 . 3 , 27 , 23 . 1 - 23 . 4 are designed as spiral inductors, for example as coils.
[0031] In FIG. 3, the design of the high-pass filter 40 is shown. It is also provided as a four stage ladder network comprising series and parallel branches between the terminal 14 and a second terminal 19 being connected with terminal 16 in the diplexer. Each of the series branches comprises a capacitor 41 . 1 , 41 . 2 , 41 . 3 and 41 . 4 , respectively. The corresponding parallel branches each comprise a series circuit of an inductor 43 . 1 - 43 . 4 and a capacitor 45 . 1 - 45 . 4 . The ladder network is terminated by a capacitor 47 coupling the terminal 19 with the common node of the series branch and the parallel branch of the fourth stage. Here, the digit of the reference number following the point indicates the stage number of the ladder network.
[0032] In the high-pass filter 40 , the inductors 43 . 2 , 43 . 3 of the second and third stage, respectively, are provided as active inductors 30 .
[0033] With reference to FIG. 4, the design of an active inductor 30 will now be described in detail. The active inductor is constructed as a component using resistors, capacitors and transistors but no inductors. However, the electrical characteristic of this active inductor is very similar to that of a passive inductor like a toroid.
[0034] The active inductor 30 comprises a first resistor 31 . 1 connected in series with a first capacitor 33 . 1 . This series circuit is coupled at its first end to a terminal 34 and at its second end to the drain of a first field effect transistor 35 . 1 . The source of this transistor 35 . 1 is coupled to a second capacitor 33 . 2 which is in turn coupled to a further terminal 34 . 2 .
[0035] The gate of the first transistor 35 . 1 is coupled to a third capacitor 33 . 3 which in turn is coupled to the drain of a second field effect transistor 35 . 2 . The source of the second transistor 35 . 2 is coupled to the source of a third field effect transistor 35 . 3 , the gate of which is coupled to the first terminal 34 . 1 .
[0036] The drain of the third transistor 35 . 3 is connected to a node 36 via a fourth capacitor 33 . 4 . The gate of the second transistor 35 . 2 is connected to said node via a fifth capacitor 33 . 5 . Finally, the drain of the second transistor 35 . 2 is connected to said node 36 via a sixth capacitor 33 . 6 .
[0037] A second resistor 31 . 2 connects said node 36 to said terminal 34 . 2 .
[0038] It is to be understood that the described design is only a preferred design for an active inductor. A person skilled in the art will contemplate variations and modifications of this design without departing the scope of the present invention as defined in the claims. One major aspect of the present invention is to avoid the employment of passive inductors, like coils. According to the present invention, at least one such passive inductor is replaced with an active inductor showing substantially the same characteristic as a passive inductor, but using active elements, like transistors. | The invention refers to a diplexer, particularly for use in microwave devices, comprising a low-pass filter and a high-pass filter, both having inductors and capacitors. It is suggested that at least one inductor of each of said filters is provided as an active inductor. | 7 |
BACKGROUND OF THE INVENTION
The invention relates generally to authentication systems and methods for digital images and more particularly to improved methods, systems and signals for authenticating digital images.
The use of digital images and videos by both consumers and professionals is pervasive. Accordingly, it has become important to provide a system and method for authenticating digital images and videos to insure that they have not been tampered with. As an example, an authentication system could insure that someone has not replaced a person's face with that of another on a digital picture or series of video frames.
Authentication systems are known which extract a short signature from images (or video frames) which can be either inserted into the image signal or stored separately. The owner of the original content can use the signature to verify whether the content has been modified or users can confirm that they are receiving authentic digital images.
Conventional content-based image authentication systems typically define an image into many blocks and extract characteristics about the blocks. For example, the image can be broken up into 16×16 blocks as in FIG. 1 or some other number of blocks, and some characteristic about the block, such as average luminance or chrominance values with respect to R, G, B or gray values. The characteristics of adjacent pairs of blocks are commonly compared and a signature is extracted based on this comparison. For example, if the average luminance value for the red component of a first block 110 of an image 100 is greater than or equal to that of a second block 120 , a one bit will be generated. Otherwise, a zero bit will be generated. The process is repeated with successive blocks until a binary signature of ones and zeros is compiled.
A disadvantage to this method is that because pairs of blocks each contribute a bit to the signature, it is possible to change the pair of blocks without affecting the signature by maintaining the difference or similarity of the compared characteristic of each block. It can be possible to reverse engineer the signature and then alter the image in such a manner to generate an identical signature and thus frustrate the authentication mechanism.
The following references discuss processing video signals, coding image blocks and authentication algorithms for digital images, the contents of which are incorporated herein by reference: WO 93/11502, U.S. Pat. No. 4,254,400, U.S. Pat. No. 5,351,095, U.S. Pat. No. 5,520,290 and U.S. Pat. No. 5,870,471.
Techniques for performing pair-wise block comparisons in a non-hierarchical technique are discussed in “Generating robust digital signature for image/video authentication”, C. Y. Lin and S. F. Chang, in Proceedings of Multimedia and Security Workshop at A. C. M. Multimedia, September 1998. Inserting and/or hiding a signature in an image signal is discussed in “Secure spread spectrum water marking for images, audio and video,” I. Cox, et al., in IEEE Int'l. Conf. on Image Processing, Vol. 3, pp. 243-246 (1996). The contents of these references are incorporated herein by reference.
Accordingly, it is desirable to provide an improved method and system for authenticating digital images which overcomes drawbacks of conventional methods and systems.
SUMMARY OF THE INVENTION
Generally speaking, in accordance with the invention, a method and system for creating authentication signatures for digital images is provided. The method and system involves partitioning the image into multiple blocks, comparing characteristics from each block and generating signature data bits based on the comparison. Each block can then be broken up into additional blocks and those blocks can be compared to create additional sets of signature bits which can be combined with the signature bits from the first set of blocks. Each or a portion of these new smaller blocks can be further broken up and the procedure can be repeated to provide an authentication signature of desired length by combining all or parts of the signature segments.
Accordingly, it is an object of the invention to provide an improved method and system for authenticating digital images and video.
Another object of the invention is to provide a method of creating an authentication signature for a digital image which is difficult to duplicate if the image is altered.
Another object of the invention is to provide an improved system for creating, storing and using authentication signatures for digital images which are difficult to duplicate if the original image is altered.
The invention accordingly comprises the several steps and relation of one or more of such steps with respect to each of the others and the product, system, signal and media adapted to effect or resulting from such steps, or as is exemplified in the following detailed description and drawings and the scope of the invention will be indicated in the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
For a fuller understanding of the invention, reference is had to the following description, taken in connection with the accompanying drawings, in which:
FIG. 1 represents a digital image divided into sixteen blocks;
FIG. 2A represents the partition of an image into four blocks at scale zero;
FIG. 2B shows each of the blocks of FIG. 2A broken down into four sub-blocks at scale one;
FIG. 3 is a flow chart of an authentication method in accordance with an embodiment of the invention;
FIG. 4 is a flow chart of an authentication method in accordance with another embodiment of the invention; and
FIG. 5 is a flow chart of an authentication method in accordance with an embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Authentication algorithms for digital data should be difficult to reverse engineer and should insure that it is difficult, if not impossible to alter the image without changing the correspondence between the authentication signature and the image itself. The authentication is preferably performed in a content-based fashion and small, non-malicious changes in the image such as brightening or subjecting the image to various coding or compression algorithms, such as a lossy JPEG-like compression should be allowed. As used herein, the term image will also be used to refer to video frames.
Authentication methods and systems in accordance with the invention use a hierarchical technique, where the image is partitioned into blocks of a selected number of pixels at a first-level or scale (scale 0) and then each or a portion of the blocks are further partitioned into sub-blocks in successive scales. At each scale, the properties or characteristics of blocks (or sub-blocks) are compared to obtain a signature for that scale, and all or part of the signatures for each scale are combined. As the individual blocks are broken down into successive scales of greater detail, the authentication signature generated at each scale can be added onto or otherwise combined with the signature generated from previous scale levels to provide a more robust signature which is more difficult to reverse engineer and evade, compared to conventional mono-scale techniques.
Referring to FIG. 2A, as a non-limiting illustration of a technique in accordance with preferred embodiments of the invention, the image (not shown) has been partitioned into four non-overlapping blocks at scale zero. These blocks are identified as A, B, C and D. The blocks together completely cover the entire image. It is also possible, in accordance with preferred embodiments of the invention, to use overlapping blocks or blocks which cover only a portion of the image, such as when authentication is only desired for a particular section of an image. Partitioning only a portion of the image can simplify the procedure if characteristic information will only be located at a certain location of the image.
A characteristic value is extracted from each block. This characteristic can be a luminance or chrominance characteristics, and the value can be the average luminance of the R (red) value (for example) over the entire block. Other values for the characteristics, such as the standard deviation of the characteristic of the block or some other characteristic value such as DCT coefficient and the like can be used. The computed characteristic values can be identified as ƒ(A), ƒ(B), ƒ(C) and ƒ(D) where ƒ is the function used to compute the desired characteristic value.
The computed characteristic values of the four blocks can then be compared as follows. The ƒ( ) values can be arranged in an ascending, descending or other predefined order. Because there are four blocks, there are twenty-four possible combinations of the ordering. (e.g., ABCD, ABDC, ADBC. . . ). A five-bit binary number can be used to represent each combination in the ordering, i.e., ABCD could be assigned 00001 and CBDA might be assigned 10010. A five-bit binary number can represent 32 different combinations. The remaining eight combinations can be used for the instances where the values of some of the ƒ( ) characteristics are equal. For example, if the four values are all equal, e.g., if the average green level of each block is identical, then a particular 5-bit number such as 11111 can be used to specify that particular combination. Thus, a 5-bit number is obtained at scale 0 (level 1) to form a part of the authentication signature.
Although four blocks are shown in this embodiment of the invention, different numbers of blocks and sub-blocks can be used in alternate embodiments of the invention. Also, the number of sub-blocks, to which a block (or sub-block) is divided need not be identical to the number of blocks or sub-blocks of a higher scale. If the number of blocks is greater than four, then the number of bits used to represent all of the combination will be greater than five.
Referring to FIG. 2B, each of the four blocks from scale 0 (FIG. 2A) are partitioned into four non-overlapping sub-blocks designated AA, AB and so forth. (As noted above, each of the blocks of FIG. 2A could have been divided into two sub-blocks, nine sub-blocks and so forth.) The partitioning of the image as shown in FIG. 2B represents scale 1 in the hierarchical decomposition. The characteristic values of each of blocks AA, AB, AC and AD are computed as discussed above and a 5-bit binary number is obtained for the four groups of sub-blocks of the scale 0 blocks. In alternate embodiments of the invention, different characteristics from those used a scale 0 can be used in each of the additional scales.
After the characteristic values of sub-blocks AA, AB, AC and AD are computed, a 5-bit binary number is obtained. The same process is repeated for the three other sets of sub-blocks at scale 1, resulting in four 5-bit numbers or 20 bits. These 20 bits are combined with the first 5-bit number and the process can be repeated successively for additional sets of sub-blocks at higher scales. The bits obtained from successive scales are concatenated to obtain a signature. For example, if four scales are used, then 5-bits are obtained from scale 0, 20-bits from 1, 80-bits from scale 2, and 320-bits from scale 3. All of these bits are concatenated to form a 425-bit level 4 authentication signature.
In alternate embodiments of the invention, the authentication signature can be obtained for a first color band and then similar signatures can be obtained for the additional color bands. The number of scales used would depend on the size of the image and the desired length of the signature.
The signature can be stored separately or sent with the image signal and transmitted with the signal or stored on a floppy disk, CD, DVD, video tape and the like.
A flow chart 500 corresponding to an authentication method in accordance with preferred embodiments of the invention is shown generally in FIG. 5 . In step 510 , image data 501 is divided into blocks. In step 520 , values corresponding to characteristics of each block are calculated. In step 530 , the blocks are ordered based on the values and in step 540 , a first-level binary code corresponding to the order of the blocks is assigned. In step 550 , each block from the first-level (scale 0) is subdivided into sub-blocks. In step 560 , values for each sub-block are calculated and in step 570 , the sub-blocks are ordered based on these values. In step 580 , sets of binary codes corresponding to the ordered sets of sub-blocks are generated and in step 590 , the binary code is combined with the first-level binary code. In step 600 , the process can be repeated and additional levels (scales) of authentication signature binary code can be developed.
Non-limiting uses of the signature obtained in accordance with preferred embodiments of the invention are illustrated in FIGS. 3 and 4.
Referring to FIG. 3, a data processor can be used to extract the authentication signature from image data using hierarchical algorithms discussed above in step 310 . In step 320 the signature of the image or video frame can be inserted into or added to the signal representing the image. In step 330 the image together with the inserted signature can be transmitted to an image receiver.
In step 340 , the authentication signature can be extracted from the image data using the hierarchical algorithm. In step 350 , the inserted (hidden) signature from the image is extracted.
In step 360 , the signature generated from the transmitted signal is compared to the signature inserted with the image. If they match, authentication is acknowledged in step 370 . If they do not match, authentication failure is indicated in step 380 .
Referring to FIG. 4, a method of authentication is illustrated where the signature is not inserted into the image signal. In step 410 the authentication signature of an image or video frame is extracted using a hierarchical algorithm in accordance with the invention. In step 420 , this signature is stored at a secure location. When verification is desired, in step 430 , the authentication signature is extracted from the image or video frame using the hierarchical algorithm. In step 440 , the signature is compared to that stored during step 420 and if they match, authentication is acknowledged in step 450 . Otherwise, authentication failure is noted in step 460 . | A method and system for creating authentication signatures for digital images and video frames is provided. The method and system involves partitioning the image into multiple blocks, comparing characteristics from each block and generating data bits based on the comparison. Each block is then broken up into additional blocks and those blocks are compared to create additional signature bits which are combined with the signature sets from the first set of blocks. Each of these new smaller blocks can be further broken up and the procedure can be repeated to provide an authentication signature of desired length. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority under 35 U.S.C. §119(e) to U.S. Provisional Application Ser. No. 61/533,980, filed Sep. 13, 2011.
FIELD OF THE INVENTION
[0002] The present invention relates to fluid fabric enhancer compositions and processes for making and using same.
BACKGROUND OF THE INVENTION
[0003] Today's consumers desire high performance fluid fabric enhancer compositions having sufficient structuring to give a rich impression and stabilize/suspend performance ingredients such as perfume microcapsules and softener particles. Current fluid fabric enhancers resort to external structurants to obtain such benefits. Unfortunately, when such current external structurants are employed in fluid fabric enhancer compositions, such compositions are difficult to: pour from a container, dose from laundry machine dispensers as the composition's thickness causes “lump” dosing rather than continuous dosing, and clean from the dispenser. In fact, in many cases fluid fabric enhancer residues remain in the dispenser even after the dispenser is washed with water. Thus what is needed is a fluid fabric enhancer composition that offers the aforementioned benefits without the rheology negatives given above.
[0004] Applicants recognized that the source of the aforementioned rheology negatives was grounded in covalent interactions/bonds that the external structurant formed in the fluid fabric enhancer composition—such interactions/bonds are difficult to break and thus result in the fluid fabric enhancer having a low shear thinning profile. As a result, Applicants disclose fluid fabric enhancer compositions that have a rich impression, that stabilize/suspend performance ingredients such as perfume microcapsules and softener particles. Applicants' fluid fabric enhancer compositions minimize/do not have the negatives of current fluid fabric enhancer compositions as they have a shear thinning profile that allows such compositions to be easily poured/dosed and that minimizes residue build up in laundry machine dispensers. While not being bound by theory, Applicants believe that such advantages are achieved as the external structurants that Applicants employ in their fluid fabric enhancer products are self assembling via hydrogen bonding instead of covalent interactions. Such external structurants also provide Applicants fluid fabric enhancers with tunable rheologies.
SUMMARY OF THE INVENTION
[0005] Fluid fabric enhancer compositions comprising external structurants and processes for making and using same.
DETAILED DESCRIPTION OF THE INVENTION
Definitions
[0006] As used herein, articles such as “a” and “an” when used in a claim, are understood to mean one or more of what is claimed or described.
[0007] As used herein, the terms “include”, “includes” and “including” are meant to be non-limiting.
[0008] As used herein, the term “solid” includes granular, powder, bar and tablet product forms.
[0009] As used herein, the term “fluid” includes liquid, gel and paste product forms.
[0010] As used herein, the term “situs” includes paper products, fabrics, garments, hard surfaces, hair and skin.
[0011] As used herein “neat perfume composition” means a perfume composition that is not contained in a perfume delivery composition.
[0012] As used herein, “non-aminofunctional organic solvent” refers to any organic solvent which contains no amino functional groups.
[0013] Unless otherwise noted, all component or composition levels are in reference to the active portion of that component or composition, and are exclusive of impurities, for example, residual solvents or by-products, which may be present in commercially available sources of such components or compositions.
[0014] All percentages and ratios are calculated by weight unless otherwise indicated. All percentages and ratios are calculated based on the total composition unless otherwise indicated.
[0015] It should be understood that every maximum numerical limitation given throughout this specification includes every lower numerical limitation, as if such lower numerical limitations were expressly written herein. Every minimum numerical limitation given throughout this specification will include every higher numerical limitation, as if such higher numerical limitations were expressly written herein. Every numerical range given throughout this specification will include every narrower numerical range that falls within such broader numerical range, as if such narrower numerical ranges were all expressly written herein.
Fluid Fabric Enhancer Composition
[0016] A fluid fabric enhancer composition comprising:
a) from about 0.5% to about 90%, from about 2% to about 70%, from about 4% to about 40%, or even from about 5% to about 25% by weight of a fabric softener active; and b) from about 0.01 wt % to about 5 wt % from about 0.05 wt % to about 2 wt % or even from about 0.1 wt % to about 0.5 wt % of a pH tuneable di-amido gellant having following formula:
[0000]
[0000] wherein R 1 and R 2 are aminofunctional end-groups; L is a backbone moiety having molecular weight from about 14 g/mol to about 500 g/mol; and at least one of L, R 1 or R 2 comprises a pH-sensitive group selected from the group consisting of
[0000]
wherein the indices n and m are integers from 1 to 20 and the ring aromatic ring moiety of the pH-sensitive group
[0000]
[0000] is optionally substituted at one or more of positions 2, 3, 5 and/or 6
said pH tuneable di-amido-gellant having a pKa of from about 0 to about 30 is disclosed.
[0021] In one aspect of said fluid fabric enhancer composition, said fabric softener active may be selected from the group consisting of quats, amines, fatty esters, sucrose esters, silicones, dispersible polyolefins, clays, polysaccharides, fatty oils, polymer latexes, fatty acids, triglycerides, fatty alcohols, fatty amides, fatty amines, dispersible polyethylenes, and mixtures thereof.
[0022] In one aspect of said fluid fabric enhancer composition, said pH tuneable di-amido gellant may have a pKa of from about 1.5 to about 14, or even from about 2 to about 9.
[0023] In one aspect of said fluid fabric enhancer composition, said pH tuneable di-amido gellant may have a molecular weight from about 150 to about 1,500 g/mol, or from about 300 g/mol to about 900 g/mol, or even from about 400 g/mol to about 700 g/mol.
[0024] In one aspect of said fluid fabric enhancer composition, said pH tuneable di-amido gellant may have a minimum gelling concentration (MGC) of from about 0.1 to about 50 mg/mL, from about 0.1 to about 12.5 mg/mL, or even from about 0.5 to about 5 mg/mL in water, at the target pH of the fluid fabric enhancer composition. The MGC as used herein can be represented as mg/ml or as a wt %, where wt % is calculated as the MGC in mg/ml divided by 10. While the invention includes fluid fabric enhancer compositions having a pH tuneable di-amido gellant concentration either above or below the MGC, the pH tuneable di-amido gellants of the invention result in particularly useful rheologies below the MGC.
[0025] In one aspect of said fluid fabric enhancer composition, said pH tuneable di-amido gellant may be selected from the group consisting of (6S,13S)-6,13-diisopropyl-4,7,12,15-tetraoxo-5,8,11,14-tetraazaoctadecane-1,18-dioic acid, (6S,14S)-6,14-diisopropyl-4,7,13,16-tetraoxo-5,8,12,15-tetraazanonadecane-1,19-dioic acid, (6S,15S)-6,15-diisopropyl-4,7,14,17-tetraoxo-5,8,13,16-tetraazaeicosane-1,20-dioic acid, (6S,16S)-6,16-diisopropyl-4,7,15,18-tetraoxo-5,8,14,17-tetraazaheneicosane-1,21-dioic acid, (6S,17S)-6,17-diisopropyl-4,7,16,19-tetraoxo-5,8,15,18-tetraazadocosane-1,22-dioic acid, (6S,18S)-6,18-diisopropyl-4,7,17,20-tetraoxo-5,8,16,19-tetraazatricosane-1,23-dioic acid, (6S,19S)-6,19-diisopropyl-4,7,18,21-tetraoxo-5,8,17,20-tetraazatetracosane-1,24-dioic acid, (6S,20S)-6,20-diisopropyl-4,7,19,22-tetraoxo-5,8,18,21-tetraazapentacosane-1,25-dioic acid, (6S,21S)-6,21-diisopropyl-4,7,20,23-tetraoxo-5,8,19,22-tetraazahexacosane-1,26-dioic acid, (6S,22S)-6,22-diisopropyl-4,7,21,24-tetraoxo-5,8,20,23-tetraazaheptacosane-1,27-dioic acid, (6S,23S)-6,23-diisopropyl-4,7,22,25-tetraoxo-5,8,21,24-tetraazaoctacosane-1,28-dioic acid, 4-[[(1S)-1-[2-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-methyl-pentanoyl]amino]ethylcarbamoyl]-2-methyl-butyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-[3-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-methyl-pentanoyl]amino]propylcarbamoyl]-2-methyl-butyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-[4-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-methyl-pentanoyl]amino]butylcarbamoyl]-2-methyl-butyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-[5-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-methyl-pentanoyl]amino]pentylcarbamoyl]-2-methyl-butyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-[6-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-methyl-pentanoyl]amino]hexylcarbamoyl]-2-methyl-butyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-[7-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-methyl-pentanoyl]amino]heptylcarbamoyl]-2-methyl-butyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-[8-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-methyl-pentanoyl]amino]octylcarbamoyl]-2-methyl-butyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-[9-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-methyl-pentanoyl]amino]nonylcarbamoyl]-2-methyl-butyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-[10-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-methyl-pentanoyl]amino]decylcarbamoyl]-2-methyl-butyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-[11-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-methyl-pentanoyl]amino]undecylcarbamoyl]-2-methyl-butyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-[12-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-methyl-pentanoyl]amino]dodecylcarbamoyl]-2-methyl-butyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-benzyl-2-[2-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-phenyl-propanoyl]amino]ethylamino]-2-oxo-ethyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-benzyl-2-[3-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-phenyl-propanoyl]amino]propylamino]-2-oxo-ethyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-benzyl-2-[7-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-phenyl-propanoyl]amino]butylamino]-2-oxo-ethyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-benzyl-2-[5-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-phenyl-propanoyl]amino]pentylamino]-2-oxo-ethyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-benzyl-2-[6-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-phenyl-propanoyl]amino]hexylamino]-2-oxo-ethyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-benzyl-2-[7-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-phenyl-propanoyl]amino]heptylamino]-2-oxo-ethyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-benzyl-2-[8-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-phenyl-propanoyl]amino]octylamino]-2-oxo-ethyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-benzyl-2-[9-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-phenyl-propanoyl]amino]nonylamino]-2-oxo-ethyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-benzyl-2-[10-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-phenyl-propanoyl]amino]decylamino]-2-oxo-ethyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-benzyl-2-[11-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-phenyl-propanoyl]amino]undecylamino]-2-oxo-ethyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-benzyl-2-[12-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-phenyl-propanoyl]amino]dodecylamino]-2-oxo-ethyl]amino]-4-oxo-butanoic acid, 4-[2-[[(1S)-1-[2-[[(2S)-2-[[2-(4-carboxyphenyl)acetyl]amino]-3-methyl-pentanoyl]amino]ethylcarbamoyl]-2-methyl-butyl]amino]-2-oxo-ethyl]benzoic acid, 4-[2-[[(1S)-1-[3-[[(2S)-2-[[2-(4-carboxyphenyl)acetyl]amino]-3-methyl-pentanoyl]amino]propylcarbamoyl]-2-methyl-butyl]amino]-2-oxo-ethyl]benzoic acid, 4-[2-[[(1S)-1-[4-[[(2S)-2-[[2-(4-carboxyphenyl)acetyl]amino]-3-methyl-pentanoyl]amino]buylcarbamoyl]-2-methyl-butyl]amino]-2-oxo-ethyl]benzoic acid, 4-[2-[[(1S)-1-[5-[[(2S)-2-[[2-(4-carboxyphenyl)acetyl]amino]-3-methyl-pentanoyl]amino]pentylcarbamoyl]-2-methyl-butyl]amino]-2-oxo-ethyl]benzoic acid, 4-[2-[[(1S)-1-[6-[[(2S)-2-[[2-(4-carboxyphenyl)acetyl]amino]-3-methyl-pentanoyl]amino]hexylcarbamoyl]-2-methyl-butyl]amino]-2-oxo-ethyl]benzoic acid, 4-[2-[[(1S)-1-[7-[[(2S)-2-[[2-(4-carboxyphenyl)acetyl]amino]-3-methyl-pentanoyl]amino]heptylcarbamoyl]-2-methyl-butyl]amino]-2-oxo-ethyl]benzoic acid, -[2-[[(1S)-1-[8-[[(2S)-2-[[2-(4-carboxyphenyl)acetyl]amino]-3-methyl-pentanoyl]amino]octylcarbamoyl]-2-methyl-butyl]amino]-2-oxo-ethyl]benzoic acid, 4-[2-[[(1S)-1-[9-[[(2S)-2-[[2-(4-carboxyphenyl)acetyl]amino]-3-methyl-pentanoyl]amino]nonylcarbamoyl]-2-methyl-butyl]amino]-2-oxo-ethyl]benzoic acid, 4-[2-[[(1S)-1-[10-[[(2S)-2-[[2-(4-carboxyphenyl)acetyl]amino]-3-methyl-pentanoyl]amino]decylcarbamoyl]-2-methyl-butyl]amino]-2-oxo-ethyl]benzoic acid, 4-[2-[[(1S)-1-[11-[[(2S)-2-[[2-(4-carboxyphenyl)acetyl]amino]-3-methyl-pentanoyl]amino]undecylcarbamoyl]-2-methyl-butyl]amino]-2-oxo-ethyl]benzoic acid, 4-[2-[[(1S)-1-[12-[[(2S)-2-[[2-(4-carboxyphenyl)acetyl]amino]-3-methyl-pentanoyl]amino]dodecylcarbamoyl]-2-methyl-butyl]amino]-2-oxo-ethyl]benzoic acid, and mixtures thereof.
[0026] In one aspect of said fluid fabric enhancer composition, said pH tuneable di-amido gellant may be selected from the group consisting of (6S,18S)-6,18-diisopropyl-4,7,17,20-tetraoxo-5,8,16,19-tetraazatricosane-1,23-dioic acid, (6S,19S)-6,19-diisopropyl-4,7,18,21-tetraoxo-5,8,17,20-tetraazatetracosane-1,24-dioic acid, (6S,20S)-6,20-diisopropyl-4,7,19,22-tetraoxo-5,8,18,21-tetraazapentacosane-1,25-dioic acid, (6S,21S)-6,21-diisopropyl-4,7,20,23-tetraoxo-5,8,19,22-tetraazahexacosane-1,26-dioic acid, (6S,22S)-6,22-diisopropyl-4,7,21,24-tetraoxo-5,8,20,23-tetraazaheptacosane-1,27-dioic acid, (6S,23S)-6,23-diisopropyl-4,7,22,25-tetraoxo-5,8,21,24-tetraazaoctacosane-1,28-dioic acid, 4-[[(1S)-1-[6-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-methyl-pentanoyl]amino]hexylcarbamoyl]-2-methyl-butyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-[7-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-methyl-pentanoyl]amino]heptylcarbamoyl]-2-methyl-butyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-[8-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-methyl-pentanoyl]amino]octylcarbamoyl]-2-methyl-butyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-[9-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-methyl-pentanoyl]amino]nonylcarbamoyl]-2-methyl-butyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-[10-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-methyl-pentanoyl]amino]decylcarbamoyl]-2-methyl-butyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-[11-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-methyl-pentanoyl]amino]undecylcarbamoyl]-2-methyl-butyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-[12-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-methyl-pentanoyl]amino]dodecylcarbamoyl]-2-methyl-butyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-benzyl-2-[6-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-phenyl-propanoyl]amino]hexylamino]-2-oxo-ethyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-benzyl-2-[7-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-phenyl-propanoyl]amino]heptylamino]-2-oxo-ethyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-benzyl-2-[8-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-phenyl-propanoyl]amino]octylamino]-2-oxo-ethyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-benzyl-2-[9-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-phenyl-propanoyl]amino]nonylamino]-2-oxo-ethyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-benzyl-2-[10-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-phenyl-propanoyl]amino]decylamino]-2-oxo-ethyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-benzyl-2-[11-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-phenyl-propanoyl]amino]undecylamino]-2-oxo-ethyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-benzyl-2-[12-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-phenyl-propanoyl]amino]dodecylamino]-2-oxo-ethyl]amino]-4-oxo-butanoic acid, 4-[2-[[(1S)-1-[6-[[(2S)-2-[[2-(4-carboxyphenyl)acetyl]amino]-3-methyl-pentanoyl]amino]hexylcarbamoyl]-2-methyl-butyl]amino]-2-oxo-ethyl]benzoic acid, 4-[2-[[(1S)-1-[7-[[(2S)-2-[[2-(4-carboxyphenyl)acetyl]amino]-3-methyl-pentanoyl]amino]heptylcarbamoyl]-2-methyl-butyl]amino]-2-oxo-ethyl]benzoic acid, 42-[[(1S)-1-[8-[[(2S)-2-[[2-(4-carboxyphenyl)acetyl]amino]-3-methyl-pentanoyl]amino]octylcarbamoyl]-2-methyl-butyl]amino]-2-oxo-ethyl]benzoic acid, 4-[2-[[(1S)-1-[9-[[(2S)-2-[[2-(4-carboxyphenyl)acetyl]amino]-3-methyl-pentanoyl]amino]nonylcarbamoyl]-2-methyl-butyl]amino]-2-oxo-ethyl]benzoic acid, 4-[2-[[(1S)-1-[10-[[(2S)-2-[[2-(4-carboxyphenyl)acetyl]amino]-3-methyl-pentanoyl]amino]decylcarbamoyl]-2-methyl-butyl]amino]-2-oxo-ethyl]benzoic acid, 4-[2-[[(1S)-1-[11-[[(2S)-2-[[2-(4-carboxyphenyl)acetyl]amino]-3-methyl-pentanoyl]amino]undecylcarbamoyl]-2-methyl-butyl]amino]-2-oxo-ethyl]benzoic acid, 4-[2-[[(1S)-1-[12-[[(2S)-2-[[2-(4-carboxyphenyl)acetyl]amino]-3-methyl-pentanoyl]amino]dodecylcarbamoyl]-2-methyl-butyl]amino]-2-oxo-ethyl]benzoic acid, and mixtures thereof.
[0027] In one aspect of said fluid fabric enhancer composition, said pH tuneable di-amido gellant may be selected from the group consisting of (6S,20S)-6,20-diisopropyl-4,7,19,22-tetraoxo-5,8,18,21-tetraazapentacosane-1,25-dioic acid, (6S,23S)-6,23-diisopropyl-4,7,22,25-tetraoxo-5,8,21,24-tetraazaoctacosane-1,28-dioic acid, 4-[[(1S)-1-[8-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-methyl-pentanoyl]amino]octylcarbamoyl]-2-methyl-butyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-[12-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-methyl-pentanoyl]amino]dodecylcarbamoyl]-2-methyl-butyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-benzyl-2-[8-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-phenyl-propanoyl]amino]octylamino]-2-oxo-ethyl]amino]-4-oxo-butanoic acid, 4-[[(1S)-1-benzyl-2-[12-[[(2S)-2-[(4-hydroxy-4-oxo-butanoyl)amino]-3-phenyl-propanoyl]amino]dodecylamino]-2-oxo-ethyl]amino]-4-oxo-butanoic acid, -[2-[[(1S)-4-[8-[[(2S)-2-[[2-(4-carboxyphenyl)acetyl]amino]-3-methyl-pentanoyl]amino]octylcarbamoyl]-2-methyl-butyl]amino]-2-oxo-ethyl]benzoic acid, 4-[2-[[(1S)-1-[12-[[(2S)-2-[[2-(4-carboxyphenyl)acetyl]amino]-3-methyl-pentanoyl]amino]dodecylcarbamoyl]-2-methyl-butyl]amino]-2-oxo-ethyl]benzoic acid, and mixtures thereof.
[0028] In one aspect of said fluid fabric enhancer composition, said composition may comprise an adjunct ingredient.
[0029] In one aspect of said fluid fabric enhancer composition, said composition may comprise from about 0.01% to about 10%, or from about 0.1% to about 5%, or even from about 0.2% to about 2% of a neat perfume composition.
[0030] In one aspect of said fluid fabric enhancer composition, said composition may comprise one or more perfume delivery systems.
[0031] In one aspect of said fluid fabric enhancer composition, said composition additionally may comprise a perfume microcapsule.
[0032] In one aspect of said fluid fabric enhancer composition, said composition additionally may comprise a perfume microcapsule that comprises an aminoplast material, polyamide material and/or an acrylate material.
[0033] In one aspect, the fluid fabric enhancer composition said composition additionally comprises a perfume microcapsule comprising a cationic, nonionic and/or anionic deposition aid.
[0034] In one aspect of said fluid fabric enhancer composition, said composition additionally may comprise a perfume microcapsule comprising a deposition aid selected from the group consisting of, a cationic polymer, a nonionic polymer, an anionic polymer and mixtures thereof.
[0035] In one aspect of said fluid fabric enhancer composition, said perfume microcapsule may comprise a cationic polymer.
[0036] In one aspect, the pH tuneable di-amido gellant may impart a shear thinning viscosity profile to the fluid fabric enhancer composition, independently from, or extrinsic from, any structuring effect of the surfactants of the composition. In one aspect, such pH tuneable di-amido gellants may include those which provide a pouring viscosity from about 50 cps to about 20,000 cps, from about 100 cps to about 10,000 cps, or even from about 200 cps to about 7,000 cps.
[0037] The pouring viscosity is measured at a shear rate of 20 sec −1 , which is a shear rate that the fluid fabric enhancer composition is typically exposed to during pouring. The viscosity is measured at 21° C. using a TA AR 2000 (or AR G2) rheometer with a 40 mm stainless steel plate having a gap of 500 microns.
[0038] In one aspect, the pH tuneable di-amido gellant may provide the fluid fabric enhancer composition with a viscosity profile that is dependent on the pH of the composition. The pH tuneable di-amido gellants may comprise at least one pH sensitive group. When a pH tuneable amido gellant is added to a polar protic solvent such as water, it is believed that the nonionic species form the viscosity building network while the ionic species are soluble and do not form a viscosity building network. By increasing or decreasing the pH (depending on the selection of the pH-sensitive groups) the amido gellant is either protonated or deprotonated. Thus, by changing the pH of the solution, the solubility, and hence the viscosity building behaviour, of the amido gellant can be controlled. By proper selection of the pH-sensitive groups, the pKa of the amido gellant can be tailored. Hence, the choice of the pH-sensitive groups can be used to select the pH at which the amido gellant builds viscosity.
Unit Dose Forms
[0039] In one aspect of said fluid fabric enhancer composition, said composition may be enclosed within a water soluble pouch material, in one aspect, comprising polyvinyl alcohols, polyvinyl alcohol copolymers and hydroxypropyl methyl cellulose (HPMC), and combinations thereof.
[0040] In one aspect, said water soluble pouch can be of any form, shape and material which is suitable for holding the fluid fabric enhancer composition, i.e. without allowing the release of the fluid fabric enhancer composition, and any additional ingredient, from said water soluble pouch prior to contact of the water soluble pouch with water. The exact execution will depend, for example, on the type and amount of the compositions in the water soluble pouch, the number of compartments in the water soluble pouch, and on the characteristics required from the water soluble pouch to hold, protect and deliver or release the fluid fabric enhancer compositions or ingredients.
[0041] The water soluble pouch may comprise a water-soluble film which fully encloses at least one compartment, comprising the fluid fabric enhancer composition. The water soluble pouch may optionally comprise additional compartments comprising fluid, solids, and mixtures thereof. Alternatively, any additional solid ingredient may be suspended in a fluid-filled compartment. A multi-compartment water soluble pouch may be desirable for such reasons as: separating chemically incompatible ingredients; or where it is desirable for a portion of the ingredients to be released into the wash earlier or later.
[0042] Water-Soluble Film:
[0043] The water-soluble film typically may have a solubility of at least 50%, at least 75%, or even at least 95%. The method for determining water-solubility of the film is given in the Test Methods. The water-soluble film typically has a dissolution time of less than 100 seconds, less than 85 seconds, less than 75 seconds, or even less than 60 seconds. The method for determining the dissolution time of the film is given in the Test Methods.
[0044] In one aspect, said films are polymeric materials, such as polymers which are formed into a film or sheet. The film can be obtained by casting, blow-moulding, extrusion or blow extrusion of the polymer material, as known in the art. In one aspect, the water-soluble film may comprise: polymers, copolymers or derivatives thereof, including polyvinyl alcohols (PVA), polyvinyl pyrrolidone, polyalkylene oxides, acrylamide, acrylic acid, cellulose, cellulose ethers, cellulose esters, cellulose amides, polyvinyl acetates, polycarboxylic acids and salts, polyaminoacids or peptides, polyamides, polyacrylamide, copolymers of maleic/acrylic acids, polysaccharides including starch and gelatine, natural gums such as xanthan gum and carragum, and mixtures thereof. In another aspect, the water-soluble film may comprise: polyacrylates and water-soluble acrylate copolymers, methylcellulose, carboxymethylcellulose, dextrin, ethylcellulose, hydroxyethyl cellulose, hydroxypropyl methylcellulose, maltodextrin, polymethacrylates, and mixtures thereof. In still another aspect, the water-soluble film may comprise: polyvinyl alcohols, polyvinyl alcohol copolymers, hydroxypropyl methyl cellulose (HPMC), and mixtures thereof. In one aspect, the level of polymer or copolymer in the film is at least 60% by weight. In one aspect, the polymer or copolymer has a weight average molecular weight of from 1,500 to 1,000,000, from 10,000 to 300,000, from 15,000 to 200,000, or even from 20,000 to 150,000 g/mol.
[0045] Copolymers and mixtures of polymers can also be used. In particular, this may be beneficial to control the mechanical and/or dissolution properties of the compartments of the water soluble pouch, depending on the application thereof and the required needs. For example, a water soluble pouch may comprise a mixture of polymers in the film, whereby one polymer material has a higher water-solubility than another polymer material, and/or one polymer material has a higher mechanical strength than another polymer material. Using copolymers and mixtures of polymers may have other benefits, including improved long-term resiliency of the water-soluble or dispersible film to the fluid composition ingredients. For instance, U.S. Pat. No. 6,787,512 discloses polyvinyl alcohol copolymer films comprising a hydrolyzed copolymer of vinyl acetate and a second sulfonic acid monomer, for improved resiliency against detergent ingredients. An example of such a film is sold by Monosol of Merrillville, Ind., US, under the brand name: M8900. In one aspect, a mixture of polymers is used, having different weight average molecular weights, for example a mixture of polyvinyl alcohol or a copolymer thereof, of a weight average molecular weight of from 10,000 to 40,000 g/mol, and of another polyvinyl alcohol or copolymer, with a weight average molecular weight of from 100,000 to 300,000 g/mol. US 2011/0189413 discloses example of blend of polyvinyl alcohol with different molecular weight.
[0046] Also useful are polymer blend compositions, for example comprising hydrolytically degradable and water-soluble polymer blends such as polylactide and polyvinyl alcohol, achieved by the mixing of polylactide and polyvinyl alcohol, typically comprising 1 to 35% by weight of the film of polylactide, and from 65% to 99% by weight of polyvinyl alcohol. In one aspect, the polymer present in the film may be from about 60% to about 98% hydrolysed, or even from about 80% to about 90%, to improve the dissolution/dispersion of the film material.
[0047] The water-soluble film herein may comprise additive ingredients other than the polymer or copolymer material. For example, it may be beneficial to add: plasticisers such as glycerol, ethylene glycol, diethyleneglycol, propylene glycol, sorbitol and mixtures thereof; additional water; and/or disintegrating aids.
[0048] Other suitable examples of commercially available water-soluble films include polyvinyl alcohol and partially hydrolysed polyvinyl acetate, alginates, cellulose ethers such as carboxymethylcellulose and methylcellulose, polyethylene oxide, polyacrylates and combinations of these.
pH Tuneable Di-Amido Gellants
[0049] The pH tuneable di-amido gellants listed for use in fluid fabric enhancers herein may have one or more of the following characteristics:
[0050] In one aspect of said pH tuneable di-amido gellant, said R 1 and R 2 end-groups may comprise amidofunctional end groups.
[0051] In one aspect, said pH tuneable di-amido gellant may comprise at least one amido functional group, and further may comprise at least one pH-sensitive group.
[0052] In one aspect, L has the formula:
[0000] L=A a -B b -C c -D d , [III]
[0000] wherein: (a+b+c+d) is from 1 to 20; and A, B, C and D are independently selected from the linking groups consisting of:
[0000]
[0000] In one aspect, L is selected from C2 to C20 hydrocarbyl chains, from C 6 to C 12 , or even from C 8 to C 10 .
[0053] In one aspect, R 1 is R 3 or
[0000]
R 2 is R 4 or
[0054]
[0000] wherein each AA is independently selected from the group consisting of:
[0000]
[0000] and R 3 and R 4 independently have the formula:
[0000] (L′) o -(L″) q -R, [IV]
[0000] wherein:
(o+q) is from 1 to 10; L′ and L″ are linking groups, independently selected from the same groups as A, B, C and D in equation [III]; and R, R′ and R″ are independently selected either from the same group as AA, either from the pH-sensitive-groups consisting of:
[0000]
[0000] or from the non-pH-sensitive groups consisting of:
[0000]
[0000] such that at least one of L, R, R′ and R″ comprises at least one pH-sensitive group. In one aspect, R may comprise the pH-sensitive group.
[0055] In one aspect, the pH tuneable di-amido gellant having structure [I] is characterized in that: L is an aliphatic linking group with a backbone chain of from 2 to 20 carbon atoms, in one aspect, L may be —(CH 2 ) n — wherein n is selected from 2 to 20, and both R 1 and R 2 have the structure:
[0000]
[0000] in one aspect, AA is selected from the group consisting of:
[0000]
[0000] and R is selected from the pH-sensitive groups consisting of:
[0000]
[0056] In another aspect, two or more of L, L′ and L″ are the same group.
[0057] The pH tuneable di-amido gellant described in formula [I] can be symmetric with respect to the L entity or can be asymmetric. Without intending to be bound by theory, it is believed that symmetric pH tuneable di-amido gellants allow for more orderly structured networks to form, whereas compositions comprising one or more asymmetric pH tuneable di-amido gellants can create disordered networks.
[0058] Suitable pH tuneable di-amido gellants having structure [I] may be selected from Table 1. In one aspect of both types of pH tuneable amido gellant structures, AA may comprise at least one of: Alanine, β-Alanine and substituted Alanines; Linear Amino-Alkyl Carboxylic Acid; Cyclic Amino-Alkyl Carboxylic Acid; Aminobenzoic Acid Derivatives; Aminobutyric Acid Derivatives; Arginine and Homologues; Asparagine; Aspartic Acid; p-Benzoyl-Phenylalanine; Biphenylalanine; Citrulline; Cyclopropylalanine; Cyclopentylalanine; Cyclohexylalanine; Cysteine, Cystine and Derivatives; Diaminobutyric Acid Derivatives; Diaminopropionic Acid; Glutamic Acid Derivatives; Glutamine; Glycine; Substituted Glycines; Histidine; Homoserine; Indole Derivatives; Isoleucine; Leucine and Derivatives; Lysine; Methionine; Naphthylalanine; Norleucine; Norvaline; Ornithine; Phenylalanine; Ring-Substituted Phenylalanines; Phenylglycine; Pipecolic Acid, Nipecotic Acid and Isonipecotic Acid; Proline; Hydroxyproline; Thiazolidine; Pyridylalanine; Serine; Statine and Analogues; Threonine; Tetrahydronorharman-3-carboxylic Acid; 1,2,3,4-Tetrahydroisoquinoline; Tryptophane; Tyrosine; Valine; and combinations thereof.
[0000]
TABLE 1
(6S,13S)-6,13-diisopropyl-4,7,12,15-tetraoxo-
5,8,11,14-tetraazaoctadecane-1,18-dioic acid
(6S,14S′)-6,14-diisopropyl-4,7,13,16-tetraoxo-
(6S,15S)-6,15-diisopropyl-4,7,14,17-tetraoxo-
5,8,12,15-tetraazanonadecane-1,19-dioic acid
5,8,13,16-tetraazaeicosane-1,20-dioic acid
(6S,16S)-6,16-diisopropyl-4,7,15,18-tetraoxo-
(6S,17S)-6,17-diisopropyl-4,7,16,19-tetraoxo-
5,8,14,17-tetraazaheneicosane-1,21-dioic acid
5,8,15,18-tetraazadocosane-1,22-dioic acid
(6S,18S)-6,18-diisopropyl-4,7,17,20-tetraoxo-
(6S,19S)-6,19-diisopropyl-4,7,18,21-tetraoxo-
5,8,16,19-tetraazatricosane-1,23-dioic acid
5,8,17,20-tetraazatetracosane-1,24-dioic acid
(6S,20S)-6,20-diisopropyl-4,7,19,22-tetraoxo-
(6S,21S)-6,21-diisopropyl-4,7,20,23-tetraoxo-
5,8,18,21-tetraazapentacosane-1,25-dioic acid
5,8,19,22-tetraazahexacosane-1,26-dioic acid
(6S,22S)-6,22-diisopropyl-4,7,21,24-tetraoxo-
(6S,23S)-6,23-diisopropyl-4,7,22,25-tetraoxo-
5,8,20,23-tetraazaheptacosane-1,27-dioic acid
5,8,21,24-tetraazaoctacosane-1,28-dioic acid
4-[[(1S)-1-[2-[[(2S)-2-[(4-hydroxy-4-oxo-
4-[[(1S)-1-[3-[[(2S)-2-[(4-hydroxy-4-oxo-
butanoyl)amino]-3-methyl-
butanoyl)amino]-3-methyl-
pentanoyl]amino]ethylcarbamoyl]-2-methyl-
pentanoyl]amino]propylc arbamoyl]-2-methyl-
butyl]amino]-4-oxo-butanoic acid
butyl]amino]-4-oxo-butanoic acid
4-[[(1S)-1-[4-[[(2S)-2-[(4-hydroxy-4-oxo-
4-[[(1S)-1-[5-[[(2S)-2-[(4-hydroxy-4-oxo-
butanoyl)amino]-3-methyl-
butanoyl)amino]-3-methyl-
pentanoyl]amino]butylcarbamoyl]-2-methyl-
pentanoyl]amino]pentylcarbamoyl]-2-methyl-
butyl]amino]-4-oxo-butanoic acid
butyl]amino]-4-oxo-butanoic acid
4-[[(1S)-1-[6-[[(2S)-2-[(4-hydroxy-4-oxo-
4-[[(1S)-1-[7-[[(2S)-2-[(4-hydroxy-4-oxo-
butanoyl)amino]-3-methyl-
butanoyl)amino]-3-methyl-
pentanoyl]amino]hexylcarbamoyl]-2-methyl-
pentanoyl]amino]heptylcarbamoyl]-2-methyl-
butyl]amino]-4-oxo-butanoic acid
butyl]amino]-4-oxo-butanoic acid
4-[[(1S)-1-[8-[[(2S)-2-[(4-hydroxy-4-oxo-
4-[[(1S)-1-[9-[[(2S)-2-[(4-hydroxy-4-oxo-
butanoyl)amino]-3-methyl-
butanoyl)amino]-3-methyl-
pentanoyl]amino]octylcarbamoyl]-2-methyl-
pentanoyl]amino]nonylcarbamoyl]-2-methyl-
butyl]amino]-4-oxo-butanoic acid
butyl]amino]-4-oxo-butanoic acid
4-[[(1S)-1-[10-[[(2S)-2-[(4-hydroxy-4-oxo-
4-[[(1S)-1-[11-[[(2S)-2-[(4-hydroxy-4-oxo-
butanoyl)amino]-3-methyl-
butanoyl)amino]-3-methyl-
pentanoyl]amino]decylcarbamoyl]-2-methyl-
pentanoyl]amino]undecylcarbamoyl]-2-
butyl]amino]-4-oxo-butanoic acid
methyl-butyl]amino]-4-oxo-butanoic acid
4-[[(1S)-1-[12-[[(2S)-2-[(4-hydroxy-4-oxo-
butanoyl)amino]-3-methyl-
pentanoyl]amino]dodecylcarbamoyl]-2-
methyl-butyl]amino]-4-oxo-butanoic acid
4-[[(1S)-1-benzyl-2-[2-[[(2S)-2-[(4-hydroxy-
4-[[(1S)-1-benzyl-2-[3-[[(2S)-2-[(4-hydroxy-
4-oxo-butanoyl)amino]-3-phenyl-
4-oxo-butanoyl)amino]-3-phenyl-
propanoyl]amino]ethylamino]-2-oxo-
propanoyl]amino]propylamino]-2-oxo-
ethyl]amino]-4-oxo-butanoic acid
ethyl]amino]-4-oxo-butanoic acid
4-[[(1S)-1-benzyl-2-[4-[[(2S)-2-[(4-hydroxy-
4-[[(1S)-1-benzyl-2-[5-[[(2S)-2-[(4-hydroxy-
4-oxo-butanoyl)amino]-3-phenyl-
4-oxo-butanoyl)amino]-3-phenyl-
propanoyl]amino]butylamino]-2-oxo-
propanoyl]amino]pentylamino]-2-oxo-
ethyl]amino]-4-oxo-butanoic acid
ethyl]amino]-4-oxo-butanoic acid
4-[[(1S)-1-benzyl-2-[6-[[(2S)-2-[(4-hydroxy-
4-[[(1S)-1-benzyl-2-[7-[[(2S)-2-[(4-hydroxy-
4-oxo-butanoyl)amino]-3-phenyl-
4-oxo-butanoyl)amino]-3-phenyl-
propanoyl]amino]hexylamino]-2-oxo-
propanoyl]amino]heptylamino]-2-oxo-
ethyl]amino]-4-oxo-butanoic acid
ethyl]amino]-4-oxo-butanoic acid
4-[[(1S)-1-benzyl-2-[8-[[(2S)-2-[(4-hydroxy-
4-[[(1S)-1-benzyl-2-[9-[[(2S)-2-[(4-hydroxy-
4-oxo-butanoyl)amino]-3-phenyl-
4-oxo-butanoyl)amino]-3-phenyl-
propanoyl]amino]octylamino]-2-oxo-
propanoyl]amino]nonylamino]-2-oxo-
ethyl]amino]-4-oxo-butanoic acid
ethyl]amino]-4-oxo-butanoic acid
4-[[(1S)-1-benzyl-2-[10-[[(2S)-2-[(4-hydroxy-
4-[[(1S)-1-benzyl-2-[11-[[(2S)-2-[(4-hydroxy-
4-oxo-butanoyl)amino]-3-phenyl-
4-oxo-butanoyl)amino]-3-phenyl-
propanoyl]amino]decylamino]-2-oxo-
propanoyl]amino]undecylamino]-2-oxo-
ethyl]amino]-4-oxo-butanoic acid
ethyl]amino]-4-oxo-butanoic acid
4-[[(1S)-1-benzyl-2-[12-[[(2S)-2-[(4-hydroxy-
4-oxo-butanoyl)amino]-3-phenyl-
propanoyl]amino]dodecylamino]-2-oxo-
ethyl]amino]-4-oxo-butanoic acid
4-[2-[[(1S)-1-[2-[[(2S)-2-[[2-(4-
4-[2-[[(1S)-1-[3-[[(2S)-2-[[2-(4-
carboxyphenyl)acetyl]amino]-3-methyl-
carboxyphenyl)acetyl]amino]-3-methyl-
pentanoyl]amino]ethylcarbamoyl]-2-methyl-
pentanoyl]amino]propylcarbamoyl]-2-methyl-
butyl]amino]-2-oxo-ethyl]benzoic acid
butyl]amino]-2-oxo-ethyl]benzoic acid
4-[2-[[(1S)-1-[4-[[(2S)-2-[[2-(4-
4-[2-[[(1S)-1-[5-[[(2S)-2-[[2-(4-
carboxyphenyl)acetyl]amino]-3-methyl-
carboxyphenyl)acetyl]amino]-3-methyl-
pentanoyl]amino]buylcarbamoyl]-2-methyl-
pentanoyl]amino]pentylcarbamoyl]-2-methyl-
butyl]amino]-2-oxo-ethyl]benzoic acid
butyl]amino]-2-oxo-ethyl]benzoic acid
4-[2-[[(1S)-1-[6-[[(2S)-2-[[2-(4-
4-[2-[[(1S)-1-[7-[[(2S)-2-[[2-(4-
carboxyphenyl)acetyl]amino]-3-methyl-
carboxyphenyl)acetyl]amino]-3-methyl-
pentanoyl]amino]hexylcarbamoyl]-2-methyl-
pentanoyl]amino]heptylcarbamoyl]-2-methyl-
butyl]amino]-2-oxo-ethyl]benzoic acid
butyl]amino]-2-oxo-ethyl]benzoic acid
4-[2-[[(1S)-1-[8-[[(2S)-2-[[2-(4-
4-[2-[[(1S)-1-[9-[[(2S)-2-[[2-(4-
carboxyphenyl)acetyl]amino]-3-methyl-
carboxyphenyl)acetyl]amino]-3-methyl-
pentanoyl]amino]octylcarbamoyl]-2-methyl-
pentanoyl]amino]nonylcarbamoyl]-2-methyl-
butyl]amino]-2-oxo-ethyl]benzoic acid
butyl]amino]-2-oxo-ethyl]benzoic acid
4-[2-[[(1S)-1-[10-[[(2S)-2-[[2-(4-
4-[2-[[(1S)-1-[11-[[(2S)-2-[[2-(4-
carboxyphenyl)acetyl]amino]-3-methyl-
carboxyphenyl)acetyl]amino]-3-methyl-
pentanoyl]amino]decylcarbamoyl]-2-methyl-
pentanoyl]amino]undecylcarbamoyl]-2-
butyl]amino]-2-oxo-ethyl]benzoic acid
methyl-butyl]amino]-2-oxo-ethyl]benzoic
acid
4-[2-[[(1S)-1-[12-[[(2S)-2-[[2-(4-
carboxyphenyl)acetyl]amino]-3-methyl-
pentanoyl]amino]dodecylcarbamoyl]-2-
methyl-butyl]amino]-2-oxo-ethyl]benzoic
acid
Secondary External Structurants
[0059] In one embodiment, the pH tuneable di-amido gellant may be combined with from 0.01 to 5% by weight of one or more additional external structurants. Without being limited by theory, it is believed that the use of an additional external structurant permits improved control of the time-dependent gelling. For example, while the pH tuneable di-amido gellant provides ultimately superior gelling, other external structurants may provide a temporary gel structure while the pH tuneable di-amido gellant is still undergoing gelling. Non-limiting examples of suitable secondary structurants are:
[0060] (i) Bacterial Cellulose
[0061] The fluid fabric enhancer composition may additionally comprise from 0.005% to 1.0% by weight of a bacterial cellulose network. The term “bacterial cellulose” encompasses any type of cellulose produced via fermentation of a bacteria of the genus Acetobacter such as CELLULON® by CPKelco U.S. and includes materials referred to popularly as microfibrillated cellulose, reticulated bacterial cellulose, and the like. Other examples of suitable bacterial cellulose can be found in U.S. Pat. No. 6,967,027; U.S. Pat. No. 5,207,826; U.S. Pat. No. 4,487,634; U.S. Pat. No. 4,373,702; U.S. Pat. No. 4,863,565 and US 2007/0027108. In one aspect, the fibres have cross sectional dimensions of 1.6 nm to 3.2 nm by 5.8 nm to 133 nm. Additionally, the bacterial cellulose fibres have an average microfibre length of at least 100 nm, or even from 100 to 1500 nm. In one aspect, the bacterial cellulose microfibres have an aspect ratio, meaning the average microfibre length divided by the widest cross sectional microfibre width, of from 100:1 to 400:1, or even from 200:1 to 300:1.
[0062] (ii) Coated Bacterial Cellulose
[0063] In one aspect, the bacterial cellulose is at least partially coated with a polymeric thickener. The at least partially coated bacterial cellulose can be prepared in accordance with the methods disclosed in US 2007/0027108 paragraphs 8 to 19. In one embodiment the at least partially coated bacterial cellulose comprises from 0.1% to 5%, from 0.5% to 3.0%, by weight of bacterial cellulose; and from 10% to 90% by weight of the polymeric thickener. Suitable bacterial cellulose may include the bacterial cellulose described above and suitable polymeric thickeners include: carboxymethylcellulose, cationic hydroxymethylcellulose, and mixtures thereof.
[0064] (iii) Non-Polymeric Crystalline Hydroxyl-Functional Materials
[0065] In one aspect, the fluid fabric enhancer composition further comprises from 0.01 to 1% by weight of the composition of a non-polymeric crystalline, hydroxyl functional structurant. Such non-polymeric crystalline, hydroxyl functional structurants generally may comprise a crystallizable glyceride which can be pre-emulsified to aid dispersion into the final fluid detergent composition. In one aspect, crystallizable glycerides may include hydrogenated castor oil or “HCO” or derivatives thereof, provided that it is capable of crystallizing in the liquid detergent composition.
[0066] (iv) Polymeric Structuring Agents
[0067] Fluid fabric enhancer compositions of the present invention may comprise from 0.01 to 5% by weight of a naturally derived and/or synthetic polymeric structurant. In one aspect, said naturally derived polymeric structurants may comprise hydroxyethyl cellulose, hydrophobically modified hydroxyethyl cellulose, carboxymethyl cellulose, polysaccharide derivatives and mixtures thereof. In one aspect, said polysaccharide derivatives may comprise pectine, alginate, arabinogalactan (gum Arabic), carrageenan, gellan gum, xanthan gum, guar gum and mixtures thereof. In one aspect, said synthetic polymeric structurants may comprise polycarboxylates, polyacrylates, hydrophobically modified ethoxylated urethanes, hydrophobically modified non-ionic polyols and mixtures thereof. In one aspect, said polycarboxylate polymer may comprise a polyacrylate, polymethacrylate or mixtures thereof. In one aspect, said polyacrylate is a copolymer of unsaturated mono- or di-carbonic acid and C 1 -C 30 alkyl ester of the (meth)acrylic acid. Such copolymers are available from Noveon inc under the tradename Carbopol Aqua 30.
[0000] Water and/or Non-Aminofunctional Organic Solvent:
The fluid fabric enhancer compositions may be diluted or concentrated aqueous liquids. In one aspect, the fluid fabric enhancer composition may be almost entirely non-aqueous, and comprising a non-aminofunctional organic solvent. Such fluid fabric enhancer compositions may comprise very little water, for instance, that may be introduced with other raw materials.
[0068] In one aspect, the fluid fabric enhancer composition comprises from 1% to 95% by weight of water and/or non-aminofunctional organic solvent. In one aspect, concentrated fluid fabric enhancer compositions may comprise from about 5% to about 85%, or from about 10% to about 50%, or even from about 15% to about 45% by weight, water and/or non-aminofunctional organic solvent.
[0000] In one aspect, said non-aminofunctional organic solvents include monohydric alcohols, dihydric alcohols, polyhydric alcohols, glycerol, glycols, polyalkylene glycols such as polyethylene glycol, and mixtures thereof. In one aspect, mixtures of “non-aminofunctional organic solvent” may be used, especially mixtures of two or more of the following: lower aliphatic alcohols such as ethanol, propanol, butanol, isopropanol; diols such as 1,2-propanediol or 1,3-propanediol; and glycerol. In one aspect, said “non-aminofunctional organic solvents” are liquid at ambient temperature and pressure (i.e. 21° C. and 1 atmosphere), and may comprise carbon, hydrogen and oxygen.
Suitable Fabric Softening Actives
[0069] The fluid fabric enhancer compositions disclosed herein comprise a fabric softening active (“FSA”). Suitable fabric softening actives, include, but are not limited to, materials selected from the group consisting of quats, amines, fatty esters, sucrose esters, silicones, dispersible polyolefins, clays, polysaccharides, fatty acids, softening oils, polymer latexes and mixtures thereof.
[0070] Non-limiting examples of water insoluble fabric care benefit agents include dispersible polyethylene and polymer latexes. These agents can be in the form of emulsions, latexes, dispersions, suspensions, and the like. In one aspect, they are in the form of an emulsion or a latex. Dispersible polyethylenes and polymer latexes can have a wide range of particle size diameters (χ 50 ) including but not limited to from about 1 nm to about 100 μm; alternatively from about 10 nm to about 10 μm. As such, the particle sizes of dispersible polyethylenes and polymer latexes are generally, but without limitation, smaller than silicones or other fatty oils.
[0071] Generally, any surfactant suitable for making polymer emulsions or emulsion polymerizations of polymer latexes can be used to make the water insoluble fabric care benefit agents of the present invention. Suitable surfactants consist of emulsifiers for polymer emulsions and latexes, dispersing agents for polymer dispersions and suspension agents for polymer suspensions. Suitable surfactants include anionic, cationic, and nonionic surfactants, or combinations thereof. In one aspect, such surfactants are nonionic and/or anionic surfactants. In one aspect, the ratio of surfactant to polymer in the water insoluble fabric care benefit agent is about 1:100 to about 1:2; alternatively from about 1:50 to about 1:5, respectively. Suitable water insoluble fabric care benefit agents include but are not limited to the examples described below.
[0072] Quat—Suitable quats include but are not limited to, materials selected from the group consisting of ester quats, amide quats, imidazoline quats, alkyl quats, amdioester quats and mixtures thereof. Suitable ester quats include but are not limited to, materials selected from the group consisting of monoester quats, diester quats, triester quats and mixtures thereof. In one aspect, a suitable ester quat is bis-(2-hydroxypropyl)-dimethylammonium methylsulphate fatty acid ester having a molar ratio of fatty acid moieties to amine moieties of from 1.85 to 1.99, an average chain length of the fatty acid moieties of from 16 to 18 carbon atoms and an iodine value of the fatty acid moieties, calculated for the free fatty acid, of from 0.5 to 60 or 15 to 50. In one aspect, the cis-trans-ratio of double bonds of unsaturated fatty acid moieties of the bis(2 hydroxypropyl)-dimethylammonium methylsulphate fatty acid ester is from 55:45 to 75:25, respectively. Suitable amide quats include but are not limited to, materials selected from the group consisting of monoamide quats, diamide quats and mixtures thereof. Suitable alkyl quats include but are not limited to, materials selected from the group consisting of mono alkyl quats, dialkyl quats quats, trialkyl quats, tetraalkyl quats and mixtures thereof.
[0073] Amines—Suitable amines include but are not limited to, materials selected from the group consisting of esteramines, amidoamines, imidazoline amines, alkyl amines, amdioester amines and mixtures thereof. Suitable ester amines include but are not limited to, materials selected from the group consisting of monoester amines, diester amines, triester amines and mixtures thereof. Suitable amido quats include but are not limited to, materials selected from the group consisting of monoamido amines, diamido amines and mixtures thereof. Suitable alkyl amines include but are not limited to, materials selected from the group consisting of mono alkylamines, dialkyl amines quats, trialkyl amines, and mixtures thereof.
[0074] In one embodiment, the fabric softening active is a quaternary ammonium compound suitable for softening fabric in a rinse step. In one embodiment, the fabric softening active is formed from a reaction product of a fatty acid and an aminoalcohol obtaining mixtures of mono-, di-, and, in one embodiment, tri-ester compounds. In another embodiment, the fabric softening active comprises one or more softener quaternary ammonium compounds such, but not limited to, as a monoalkyquaternary ammonium compound, dialkylquaternary ammonium compound, a diamido quaternary compound, a diester quaternary ammonium compound, or a combination thereof.
[0075] In one aspect, the fabric softening active comprises a diester quaternary ammonium or protonated diester ammonium (hereinafter “DQA”) compound composition. In certain embodiments of the present invention, the DQA compound compositions also encompass diamido fabric softening actives s and fabric softening actives with mixed amido and ester linkages as well as the aforementioned diester linkages, all herein referred to as DQA.
[0076] In one aspect, said fabric softening active may comprise, as the principal active, compounds of the following formula:
[0000] {R 4-m —N + —[X—Y—R 1 ] m }X − (1)
[0000] wherein each R comprises either hydrogen, a short chain C 1 -C 6 , in one aspect a C 1 -C 3 alkyl or hydroxyalkyl group, for example methyl, ethyl, propyl, hydroxyethyl, and the like, poly(C 2-3 alkoxy), polyethoxy, benzyl, or mixtures thereof; each X is independently (CH 2 )n, CH 2 —CH(CH 3 )— or CH—(CH 3 )—CH 2 —; each Y may comprise —O—(O)C—, —C(O)—O—, —NR—C(O)—, or —C(O)—NR—; each m is 2 or 3; each n is from 1 to about 4, in one aspect 2; the sum of carbons in each R 1 , plus one when Y is —O—(O)C— or —NR—C(O)—, may be C 12 -C 22 , or C 14 -C 20 , with each R 1 being a hydrocarbyl, or substituted hydrocarbyl group; and X − may comprise any softener-compatible anion. In one aspect, the softener-compatible anion may comprise chloride, bromide, methylsulfate, ethylsulfate, sulfate, and nitrate. In another aspect, the softener-compatible anion may comprise chloride or methyl sulfate.
[0077] In another aspect, the fabric softening active may comprise the general formula:
[0000] [R 3 N + CH 2 CH(YR 1 )(CH 2 YR 1 )X −
[0000] wherein each Y, R, R 1 , and X − have the same meanings as before. Such compounds include those having the formula:
[0000] [CH 3 ] 3 N (+) [CH 2 CH(CH 2 O(O)CR 1 )O(O)CR 1 ]Cl (−) (2)
[0000] wherein each R may comprise a methyl or ethyl group. In one aspect, each R 1 may comprise a C 15 to C 19 group. As used herein, when the diester is specified, it can include the monoester that is present.
[0078] These types of agents and general methods of making them are disclosed in U.S. Pat. No. 4,137,180. An example of a suitable DEQA (2) is the “propyl” ester quaternary ammonium fabric softener active comprising the formula 1,2-di(acyloxy)-3-trimethylammoniopropane chloride.
[0079] A third type of useful fabric softening active has the formula:
[0000] [R 4-m —N + —R 1 m ]X − (3)
[0000] wherein each R, R 1 , m and X − have the same meanings as before.
[0080] In a further aspect, the fabric softening active may comprise the formula:
[0000]
[0000] wherein each R, R 1 , and A − have the definitions given above; R 2 may comprise a C 1-6 alkylene group, in one aspect an ethylene group; and G may comprise an oxygen atom or an —NR— group;
[0081] In a yet further aspect, the fabric softening active may comprise the formula:
[0000]
[0000] wherein R 1 , R 2 and G are defined as above.
[0082] In a further aspect, the fabric softening active may comprise condensation reaction products of fatty acids with dialkylenetriamines in, e.g., a molecular ratio of about 2:1, said reaction products containing compounds of the formula:
[0000] R 1 —C(O)—NH—R 2 —NH—R 3 —NH—C(O)—R 1 (6)
[0000] wherein R 1 , R 2 are defined as above, and R 3 may comprise a C 1-6 alkylene group, in one aspect, an ethylene group and wherein the reaction products may optionally be quaternized by the additional of an alkylating agent such as dimethyl sulfate. Such quaternized reaction products are described in additional detail in U.S. Pat. No. 5,296,622.
[0083] In a yet further aspect, the fabric softening active may comprise the formula:
[0000] [R 1 —C(O)—NR—R 2 —N(R) 2 —R 3 —NR—C(O)—R 1 ] + A − (7)
[0000] wherein R, R 1 , R 2 , R 3 and A − are defined as above;
[0084] In a yet further aspect, the fabric softening active may comprise reaction products of fatty acid with hydroxyalkylalkylenediamines in a molecular ratio of about 2:1, said reaction products containing compounds of the formula:
[0000] R 1 —C(O)—NH—R 2 —N(R 3 OH)—C(O)—R 1 (8)
[0000] wherein R 1 , R 2 and R 3 are defined as above;
[0085] In a yet further aspect, the fabric softening active may comprise the formula:
[0000]
[0000] wherein R, R 1 , R 2 , and A − are defined as above.
[0086] In yet a further aspect, the fabric softening active may comprise the formula (10);
[0000]
[0000] wherein;
X 1 is a C 2-3 alkyl group, in one aspect, an ethyl group; X 2 and X 3 are independently C 1-6 linear or branched alkyl or alkenyl groups, in one aspect, methyl, ethyl or isopropyl groups; R 1 and R 2 are independently C 8-22 linear or branched alkyl or alkenyl groups; characterized in that; A and B are independently selected from the group comprising —O—(C═O)—, —(C═O)—O—, or mixtures thereof, in one aspect, —O—(C═O)—
[0091] Non-limiting examples of fabric softening actives comprising formula (1) are N,N-bis(stearoyl-oxy-ethyl) N,N-dimethyl ammonium chloride, N,N-bis(tallowoyl-oxy-ethyl) N,N-dimethyl ammonium chloride, N,N-bis(stearoyl-oxy-ethyl) N-(2 hydroxyethyl) N-methyl ammonium methylsulfate.
[0092] Non-limiting examples of fabric softening actives comprising formula (2) is 1, 2 di(stearoyl-oxy) 3 trimethyl ammoniumpropane chloride.
[0093] Non-limiting examples of fabric softening actives comprising formula (3) include dialkylenedimethylammonium salts such as dicanoladimethylammonium chloride, di(hard)tallowedimethylammonium chloride dicanoladimethylammonium methylsulfate, and mixtures thereof. An example of commercially available dialkylenedimethylammonium salts usable in the present invention is dioleyldimethylammonium chloride available from Witco Corporation under the trade name Adogen® 472 and dihardtallow dimethylammonium chloride available from Akzo Nobel Arquad 2HT75.
[0094] A non-limiting example of fabric softening actives comprising formula (4) is 1-methyl-1-stearoylamidoethyl-2-stearoylimidazolinium methylsulfate wherein R 1 is an acyclic aliphatic C 15 -C 17 hydrocarbon group, R 2 is an ethylene group, G is a NH group, R 5 is a methyl group and A − is a methyl sulfate anion, available commercially from the Witco Corporation under the trade name Varisoft®.
[0095] A non-limiting example of fabric softening actives comprising formula (5) is 1-tallowylamidoethyl-2-tallowylimidazoline wherein R 1 is an acyclic aliphatic C 15 -C 17 hydrocarbon group, R 2 is an ethylene group, and G is a NH group.
[0096] A non-limiting example of a fabric softening active comprising formula (6) is the reaction products of fatty acids with diethylenetriamine in a molecular ratio of about 2:1, said reaction product mixture containing N,N″-dialkyldiethylenetriamine with the formula:
[0000] R 1 —C(O)—NH—CH 2 CH 2 —NH—CH 2 CH 2 —NH—C(O)—R 1
[0000] wherein R 1 is an alkyl group of a commercially available fatty acid derived from a vegetable or animal source, such as Emersol® 223LL or Emersol® 7021, available from Henkel Corporation, and R 2 and R 3 are divalent ethylene groups.
[0097] A non-limiting example of Compound (7) is a di-fatty amidoamine based softener having the formula:
[0000] [R 1 —C(O)—NH—CH 2 CH 2 —N(CH 3 )(CH 2 CH 2 OH)—CH 2 CH 2 —NH—C(O)—R 1 ] + CH 3 SO 4 −
[0000] wherein R 1 is an alkyl group. An example of such compound is that commercially available from the Witco Corporation e.g. under the trade name Varisoft® 222LT.
[0098] An example of a fabric softening active comprising formula (8) is the reaction products of fatty acids with N-2-hydroxyethylethylenediamine in a molecular ratio of about 2:1, said reaction product mixture containing a compound of the formula:
[0000] R 1 —C(O)—NH—CH 2 CH 2 —N(CH 2 CH 2 OH)—C(O)—R 1
[0000] wherein R 1 —C(O) is an alkyl group of a commercially available fatty acid derived from a vegetable or animal source, such as Emersol® 223LL or Emersol® 7021, available from Henkel Corporation.
[0099] An example of a fabric softening active comprising formula (9) is the diquaternary compound having the formula:
[0000]
[0000] wherein R 1 is derived from fatty acid. Such compound is available from Witco Company.
[0100] A non-limiting example of a fabric softening active comprising formula (10) is a dialkyl imidazoline diester compound, where the compound is the reaction product of N-(2-hydroxyethyl)-1,2-ethylenediamine or N-(2-hydroxyisopropyl)-1,2-ethylenediamine with glycolic acid, esterified with fatty acid, where the fatty acid is (hydrogenated) tallow fatty acid, palm fatty acid, hydrogenated palm fatty acid, oleic acid, rapeseed fatty acid, hydrogenated rapeseed fatty acid or a mixture of the above.
[0101] It will be understood that combinations of softener actives disclosed above are suitable for use in this invention.
Anion A
[0102] In the cationic nitrogenous salts herein, the anion A − , which comprises any softener compatible anion, provides electrical neutrality. Most often, the anion used to provide electrical neutrality in these salts is from a strong acid, especially a halide, such as chloride, bromide, or iodide. However, other anions can be used, such as methylsulfate, ethylsulfate, acetate, formate, sulfate, carbonate, and the like. In one aspect, the anion A may comprise chloride or methylsulfate. The anion, in some aspects, may carry a double charge. In this aspect, A − represents half a group.
[0000] In one embodiment, the fabric softening agent comprises an fabric softening agent described in U.S. Pat. Pub. No. 2004/0204337 A1, published Oct. 14, 2004 to Corona et al., from paragraphs 30-79.
[0103] In another embodiment, the fabric softening agent is one described in U.S. Pat. Pub. No. 2004/0229769 A1, published Nov. 18, 2005, to Smith et al., on paragraphs 26-31; or U.S. Pat. No. 6,494,920, at column 1, line 51 et seq. detailing an “esterquat” or a quaternized fatty acid triethanolamine ester salt.
[0104] In one embodiment, the fabric softening agent is chosen from at least one of the following: ditallowoyloxyethyl dimethyl ammonium chloride, dihydrogenated-tallowoyloxyethyl dimethyl ammonium chloride, ditallow dimethyl ammonium chloride, dihydrogenatedtallow dimethyl ammonium chloride, ditallowoyloxyethyl methylhydroxyethylammonium methyl sulfate, dihydrogenated-tallowoyloxyethyl methyl hydroxyethylammonium chloride, or combinations thereof.
[0105] Polyssacharides
[0106] One aspect of the invention provides a fabric enhancer composition comprising a cationic starch as a fabric softening active. In one embodiment, the fabric care compositions of the present invention generally comprise cationic starch at a level of from about 0.1% to about 7%, alternatively from about 0.1% to about 5%, alternatively from about 0.3% to about 3%, and alternatively from about 0.5% to about 2.0%, by weight of the composition. Cationic starch as a fabric softening active is described in U.S. Pat. Pub. 2004/0204337 A1, published Oct. 14, 2004, to Corona et al., at paragraphs 16-32. Suitable cationic starches for use in the present compositions are commercially-available from Cerestar under the trade name C*BOND® and from National Starch and Chemical Company under the trade name CATO® 2A.
[0107] Silicone
[0108] In one embodiment, the fabric softening composition comprises a silicone. Suitable levels of silicone may comprise from about 0.1% to about 70%, alternatively from about 0.3% to about 40%, alternatively from about 0.5% to about 30%, alternatively from about 1% to about 20% by weight of the composition. Useful silicones can be any silicone comprising compound. In one embodiment, the silicone is a polydialkylsilicone, alternatively a polydimethyl silicone (polydimethyl siloxane or “PDMS”), or a derivative thereof. In another embodiment, the silicone is chosen from an aminofunctional silicone, amino-polyether silicone, alkyloxylated silicone, cationic silicone, ethoxylated silicone, propoxylated silicone, ethoxylated/propoxylated silicone, quaternary silicone, or combinations thereof. Other useful silicone materials may include materials of the formula:
[0000] HO[Si(CH 3 ) 2 —O] x {Si(OH)[(CH 2 ) 3 —NH—(CH 2 ) 2 —NH 2 ]O} y H
[0000] wherein x and y are integers which depend on the molecular weight of the silicone, in one aspect, such silicone has a molecular weight such that the silicone exhibits a viscosity of from about 500 cSt to about 500,000 cSt at 25° C. This material is also known as “amodimethicone”.
[0109] In another embodiment, the silicone may be chosen from a random or blocky organosilicone polymer having the following formula:
[0000] [R 1 R 2 R 3 SiO 1/2 ] (j+2 )[(R 4 Si(X—Z)O 2/2 ] k [R 4 R 4 SiO 2/2 ] m [R 4 SiO 3/2 ] j
[0000] wherein:
j is an integer from 0 to about 98; in one aspect j is an integer from 0 to about 48; in one aspect, j is 0; k is an integer from 0 to about 200, in one aspect k is an integer from 0 to about 50; when k=0, at least one of R 1 , R 2 or R 3 is —X—Z; m is an integer from 4 to about 5,000; in one aspect m is an integer from about 10 to about 4,000; in another aspect m is an integer from about 50 to about 2,000;
R 1 , R 2 and R 3 are each independently selected from the group consisting of H, OH, C 1 -C 32 alkyl, C 1 -C 32 substituted alkyl, C 5 -C 32 or C 6 -C 32 aryl, C 5 -C 32 or C 6 -C 32 substituted aryl, C 6 -C 32 alkylaryl, C 6 -C 32 substituted alkylaryl, C 1 -C 32 alkoxy, C 1 -C 32 substituted alkoxy and X—Z; each R 4 is independently selected from the group consisting of H, OH, C 1 -C 32 alkyl, C 1 -C 32 substituted alkyl, C 5 -C 32 or C 6 -C 32 aryl, C 5 -C 32 or C 6 -C 32 substituted aryl, C 6 -C 32 alkylaryl, C 6 -C 32 substituted alkylaryl, C 1 -C 32 alkoxy and C 1 -C 32 substituted alkoxy; each X in said alkyl siloxane polymer comprises a substituted or unsubsitituted divalent alkylene radical comprising 2-12 carbon atoms, in one aspect each divalent alkylene radical is independently selected from the group consisting of —(CH 2 ) s — wherein s is an integer from about 2 to about 8, from about 2 to about 4; in one aspect, each X in said alkyl siloxane polymer comprises a substituted divalent alkylene radical selected from the group consisting of: —CH 2 —CH(OH)—CH 2 —; —CH 2 —CH 2 —CH(OH)—; and
[0000]
each Z is selected independently from the group consisting of
[0000]
with the proviso that when Z is a quat, Q cannot be an amide, imine, or urea moiety and if Q is an amide, imine, or urea moiety, then any additional Q bonded to the same nitrogen as said amide, imine, or urea moiety must be H or a C 1 -C 6 alkyl, in one aspect, said additional Q is H; for Z A n− is a suitable charge balancing anion. In one aspect A n− is selected from the group consisting of Cl − , Br − , I − , methylsulfate, toluene sulfonate, carboxylate and phosphate; and at least one Q in said organosilicone is independently selected from —CH 2 —CH(OH)—CH 2 —R 5 ;
[0000]
each additional Q in said organosilicone is independently selected from the group comprising of H, C 1 -C 32 alkyl, C 1 -C 32 substituted alkyl, C 5 -C 32 or C 6 -C 32 aryl, C 5 -C 32 or C 6 -C 32 substituted aryl, C 6 -C 32 alkylaryl, C 6 -C 32 substituted alkylaryl, —CH 2 —CH(OH)—CH 2 —R 5 ;
[0000]
wherein each R 5 is independently selected from the group consisting of H, C 1 -C 32 alkyl, C 1 -C 32 substituted alkyl, C 5 -C 32 or C 6 -C 32 aryl, C 5 -C 32 or C 6 -C 32 substituted aryl, C 6 -C 32 alkylaryl, C 6 -C 32 substituted alkylaryl, —(CHR 6 —CHR 6 —O—) w -L and a siloxyl residue;
each R 6 is independently selected from H, C 1 -C 18 alkyl
each L is independently selected from —C(O)—R 7 or R 7 ;
W is an integer from 0 to about 500, in one aspect w is an integer from about 1 to about 200; in one aspect w is an integer from about 1 to about 50;
each R 7 is selected independently from the group consisting of H; C 1 -C 32 alkyl; C 1 -C 32 substituted alkyl, C 5 -C 32 or C 6 -C 32 aryl, C 5 -C 32 or C 6 -C 32 substituted aryl, C 6 -C 32 alkylaryl; C 6 -C 32 substituted alkylaryl and a siloxyl residue;
each T is independently selected from H, and
[0000]
and wherein each v in said organosilicone is an integer from 1 to about 10, in one aspect, v is an integer from 1 to about 5 and the sum of all v indices in each Q in the said organosilicone is an integer from 1 to about 30 or from 1 to about 20 or even from 1 to about 10.
[0125] In another embodiment, the silicone may be chosen from a random or blocky organosilicone polymer having the following formula:
[0000] [R 1 R 2 R 3 SiO 1/2 ] (j+2) [(R 4 Si(X—Z)O 2/2 ] k [R 4 R 4 SiO 2/2 ] m [R 4 SiO 3/2 ] j ,
[0126] wherein
j is an integer from 0 to about 98; in one aspect j is an integer from 0 to about 48; in one aspect, j is 0; k is an integer from 0 to about 200; when k=0, at least one of R 1 , R 2 or R 3 =—X—Z, in one aspect, k is an integer from 0 to about 50 m is an integer from 4 to about 5,000; in one aspect m is an integer from about 10 to about 4,000; in another aspect m is an integer from about 50 to about 2,000;
R 1 , R 2 and R 3 are each independently selected from the group consisting of H, OH, C 1 -C 32 alkyl, C 1 -C 32 substituted alkyl, C 5 -C 32 or C 6 -C 32 aryl, C 5 -C 32 or C 6 -C 32 substituted aryl, C 6 -C 32 alkylaryl, C 6 -C 32 substituted alkylaryl, C 1 -C 32 alkoxy, C 1 -C 32 substituted alkoxy and X—Z; each R 4 is independently selected from the group consisting of H, OH, C 1 -C 32 alkyl, C 1 -C 32 substituted alkyl, C 5 -C 32 or C 6 -C 32 aryl, C 5 -C 32 or C 6 -C 32 substituted aryl, C 6 -C 32 alkylaryl, C 6 -C 32 substituted alkylaryl, C 1 -C 32 alkoxy and C 1 -C 32 substituted alkoxy; each X comprises of a substituted or unsubstituted divalent alkylene radical comprising 2-12 carbon atoms; in one aspect each X is independently selected from the group consisting of —(CH 2 ) s —O—; —CH 2 —CH(OH)—CH 2 —O—;
[0000]
wherein each s independently is an integer from about 2 to about 8, in one aspect s is an integer from about 2 to about 4;
At least one Z in the said organosiloxane is selected from the group consisting of R 5 ;
[0000]
provided that when
X is
[0000]
then Z=—OR 5 or
[0000]
wherein A − is a suitable charge balancing anion. In one aspect A − is selected from the group consisting of Cl − , Br − ,
I − , methylsulfate, toluene sulfonate, carboxylate and phosphate and
each additional Z in said organosilicone is independently selected from the group comprising of H, C 1 -C 32 alkyl, C 1 -C 32 substituted alkyl, C 5 -C 32 or C 6 -C 32 aryl, C 5 -C 32 or C 6 -C 32 substituted aryl, C 6 -C 32 alkylaryl, C 6 -C 32 substituted alkylaryl, R 5 ,
[0000]
provided that when
X is
[0000]
then Z=—OR 5 or
[0000]
each R 5 is independently selected from the group consisting of H; C 1 -C 32 alkyl; C 1 -C 32 substituted alkyl, C 5 -C 32 or C 6 -C 32 aryl, C 5 -C 32 or C 6 -C 32 substituted aryl or C 6 -C 32 alkylaryl, or C 6 -C 32 substituted alkylaryl,
—(CHR 6 —CHR 6 —O—) w —CHR 6 —CHR 6 -L and siloxyl residue wherein each L is independently selected from —O—C(O)—R 7 or —O—R 7 ;
[0000]
w is an integer from 0 to about 500, in one aspect w is an integer from 0 to about 200, one aspect w is an integer from 0 to about 50;
each R 6 is independently selected from H or C 1 -C 18 alkyl;
each R 7 is independently selected from the group consisting of H; C 1 -C 32 alkyl; C 1 -C 32 substituted alkyl, C 5 -C 32 or C 6 -C 32 aryl, C 5 -C 32 or C 6 -C 32 substituted aryl, C 6 -C 32 alkylaryl, and C 6 -C 32 substituted aryl, and a siloxyl residue;
each T is independently selected from H;
[0000]
wherein each v in said organosilicone is an integer from 1 to about 10, in one aspect, v is an integer from 1 to about 5 and the sum of all v indices in each Z in the said organosilicone is an integer from 1 to about 30 or from 1 to about 20 or even from 1 to about 10.
[0147] In one embodiment, the silicone is one comprising a relatively high molecular weight. A suitable way to describe the molecular weight of a silicone includes describing its viscosity. A high molecular weight silicone is one having a viscosity of from about 10 cSt to about 3,000,000 cSt, or from about 100 cSt to about 1,000,000 cSt, or from about 1,000 cSt to about 600,000 cSt, or even from about 6,000 cSt to about 300,000 cSt,
[0148] Sucrose Esters
[0149] Nonionic fabric care benefit agents can comprise sucrose esters, and are typically derived from sucrose and fatty acids. Sucrose ester is composed of a sucrose moiety having one or more of its hydroxyl groups esterified.
[0150] Sucrose is a disaccharide having the following formula:
[0000]
[0151] Alternatively, the sucrose molecule can be represented by the formula: M(OH) 8 , wherein M is the disaccharide backbone and there are total of 8 hydroxyl groups in the molecule.
[0152] Thus, sucrose esters can be represented by the following formula:
[0000] M(OH) 8-x (OC(O)R 1 ) x
[0000] wherein x is the number of hydroxyl groups that are esterified, whereas (8-x) is the hydroxyl groups that remain unchanged; x is an integer selected from 1 to 8, alternatively from 2 to 8, alternatively from 3 to 8, or from 4 to 8; and R 1 moieties are independently selected from C 1 -C 22 alkyl or C 1 -C 30 alkoxy, linear or branched, cyclic or acyclic, saturated or unsaturated, substituted or unsubstituted.
[0153] In one embodiment, the R 1 moieties comprise linear alkyl or alkoxy moieties having independently selected and varying chain length. For example, R 1 may comprise a mixture of linear alkyl or alkoxy moieties wherein greater than about 20% of the linear chains are C 18 , alternatively greater than about 50% of the linear chains are C 18 , alternatively greater than about 80% of the linear chains are C 18 .
[0154] In another embodiment, the R 1 moieties comprise a mixture of saturate and unsaturated alkyl or alkoxy moieties; the degree of unsaturation can be measured by “Iodine Value” (hereinafter referred as “IV”, as measured by the standard AOCS method). The IV of the sucrose esters suitable for use herein ranges from about 1 to about 150, or from about 2 to about 100, or from about 5 to about 85. The R 1 moieties may be hydrogenated to reduce the degree of unsaturation. In the case where a higher IV is preferred, such as from about 40 to about 95, then oleic acid and fatty acids derived from soybean oil and canola oil are the starting materials.
[0155] In a further embodiment, the unsaturated R 1 moieties may comprise a mixture of “cis” and “trans” forms about the unsaturated sites. The “cis”/“trans” ratios may range from about 1:1 to about 50:1, or from about 2:1 to about 40:1, or from about 3:1 to about 30:1, or from about 4:1 to about 20:1.
[0156] Dispersible Polyolefins
[0157] Generally, all dispersible polyolefins that provide fabric care benefits can be used as water insoluble fabric care benefit agents in the present invention. The polyolefins can be in the format of waxes, emulsions, dispersions or suspensions. Non-limiting examples are discussed below.
[0158] In one embodiment, the polyolefin is chosen from a polyethylene, polypropylene, or a combination thereof. The polyolefin may be at least partially modified to contain various functional groups, such as carboxyl, alkylamide, sulfonic acid or amide groups. In another embodiment, the polyolefin is at least partially carboxyl modified or, in other words, oxidized.
[0159] For ease of formulation, the dispersible polyolefin may be introduced as a suspension or an emulsion of polyolefin dispersed by use of an emulsifying agent. The polyolefin suspension or emulsion may comprise from about 1% to about 60%, alternatively from about 10% to about 55%, alternatively from about 20% to about 50% by weight of polyolefin. The polyolefin may have a wax dropping point (see ASTM D3954-94, volume 15.04- - - “Standard Test Method for Dropping Point of Waxes”) from about 20° to about 170° C., alternatively from about 50° to about 140° C. Suitable polyethylene waxes are available commercially from suppliers including but not limited to Honeywell (A-C polyethylene), Clariant (Velustrol® emulsion), and BASF (LUWAX®).
[0160] When an emulsion is employed with the dispersible polyolefin, the emulsifier may be any suitable emulsification agent. Non-limiting examples include an anionic, cationic, nonionic surfactant, or a combination thereof. However, almost any suitable surfactant or suspending agent may be employed as the emulsification agent. The dispersible polyolefin is dispersed by use of an emulsification agent in a ratio to polyolefin wax of about 1:100 to about 1:2, alternatively from about 1:50 to about 1:5, respectively.
[0161] Polymer Latexes
[0162] Polymer latex is made by an emulsion polymerization which includes one or more monomers, one or more emulsifiers, an initiator, and other components familiar to those of ordinary skill in the art. Generally, all polymer latexes that provide fabric care benefits can be used as water insoluble fabric care benefit agents of the present invention. Non-limiting examples of suitable polymer latexes include those disclosed in US 2004/0038851 A1; and US 2004/0065208 A1. Additional non-limiting examples include the monomers used in producing polymer latexes such as: (1) 100% or pure butylacrylate; (2) butylacrylate and butadiene mixtures with at least 20% (weight monomer ratio) of butylacrylate; (3) butylacrylate and less than 20% (weight monomer ratio) of other monomers excluding butadiene; (4) alkylacrylate with an alkyl carbon chain at or greater than C 6 ; (5) alkylacrylate with an alkyl carbon chain at or greater than C 6 and less than 50% (weight monomer ratio) of other monomers; (6) a third monomer (less than 20% weight monomer ratio) added into an aforementioned monomer systems; and (7) combinations thereof.
[0163] Polymer latexes that are suitable fabric care benefit agents in the present invention may include those having a glass transition temperature of from about −120° C. to about 120° C., alternatively from about −80° C. to about 60° C. Suitable emulsifiers include anionic, cationic, nonionic and amphoteric surfactants. Suitable initiators include initiators that are suitable for emulsion polymerization of polymer latexes. The particle size diameter (χ 50 ) of the polymer latexes can be from about 1 nm to about 10 μm, alternatively from about 10 nm to about 1 μm, or even from about 10 nm to about 20 nm.
[0164] Fatty Acid
[0165] One aspect of the invention provides a fabric softening composition comprising a fatty acid, such as a free fatty acid. The term “fatty acid” is used herein in the broadest sense to include unprotonated or protonated forms of a fatty acid; and includes fatty acid that is bound or unbound to another chemical moiety as well as the various combinations of these species of fatty acid. One skilled in the art will readily appreciate that the pH of an aqueous composition will dictate, in part, whether a fatty acid is protonated or unprotonated. In another embodiment, the fatty acid is in its unprotonated, or salt form, together with a counter ion, such as, but not limited to, calcium, magnesium, sodium, potassium and the like. The term “free fatty acid” means a fatty acid that is not bound (to another chemical moiety (covalently or otherwise) to another chemical moiety.
[0166] In one embodiment, the fatty acid may include those containing from about 12 to about 25, from about 13 to about 22, or even from about 16 to about 20, total carbon atoms, with the fatty moiety containing from about 10 to about 22, from about 12 to about 18, or even from about 14 (mid-cut) to about 18 carbon atoms.
[0167] The fatty acids of the present invention may be derived from (1) an animal fat, and/or a partially hydrogenated animal fat, such as beef tallow, lard, etc.; (2) a vegetable oil, and/or a partially hydrogenated vegetable oil such as canola oil, safflower oil, peanut oil, sunflower oil, sesame seed oil, rapeseed oil, cottonseed oil, corn oil, soybean oil, tall oil, rice bran oil, palm oil, palm kernel oil, coconut oil, other tropical palm oils, linseed oil, tung oil, etc.; (3) processed and/or bodied oils, such as linseed oil or tung oil via thermal, pressure, alkali-isomerization and catalytic treatments; (4) a mixture thereof, to yield saturated (e.g. stearic acid), unsaturated (e.g. oleic acid), polyunsaturated (linoleic acid), branched (e.g. isostearic acid) or cyclic (e.g. saturated or unsaturated α-disubstituted cyclopentyl or cyclohexyl derivatives of polyunsaturated acids) fatty acids. Non-limiting examples of fatty acids (FA) are listed in U.S. Pat. No. 5,759,990 at col 4, lines 45-66.
[0168] Mixtures of fatty acids from different fat sources can be used.
[0169] In one aspect, at least a majority of the fatty acid that is present in the fabric softening composition of the present invention is unsaturated, e.g., from about 40% to 100%, from about 55% to about 99%, or even from about 60% to about 98%, by weight of the total weight of the fatty acid present in the composition, although fully saturated and partially saturated fatty acids can be used. As such, the total level of polyunsaturated fatty acids (TPU) of the total fatty acid of the inventive composition may be from about 0% to about 75% by weight of the total weight of the fatty acid present in the composition.
[0170] The cis/trans ratio for the unsaturated fatty acids may be important, with the cis/trans ratio (of the C18:1 material) being from at least about 1:1, at least about 3:1, from about 4:1 or even from about 9:1 or higher.
[0171] Branched fatty acids such as isostearic acid are also suitable since they may be more stable with respect to oxidation and the resulting degradation of color and odor quality.
[0172] The Iodine Value or “IV” measures the degree of unsaturation in the fatty acid. In one embodiment of the invention, the fatty acid has an IV from about 40 to about 140, from about 50 to about 120 or even from about 85 to about 105.
[0173] Examples of fatty acids are described in WO06007911A1 and WO06007899A1
[0174] Softening Oils
[0175] Another class of optional fabric care actives is softening oils, which include but are not limited to, vegetable oils (such as soybean, sunflower, and canola), hydrocarbon based oils (natural and synthetic petroleum lubricants, in one aspect polyolefins, isoparaffins, and cyclic paraffins), triolein, fatty esters, fatty alcohols, fatty amines, fatty amides, and fatty ester amines. Oils can be combined with fatty acid softening agents, clays, and silicones.
[0176] Clays
[0177] In one embodiment of the invention, the fabric care composition may comprise a clay as a fabric care active. In one embodiment clay can be a softener or co-softeners with another softening active, for example, silicone. Suitable clays include those materials classified geologically smectites and are described in USPA No. 2003/0216274 A1. Other suitable clays are described in U.S. Patent Application Publication No. 20050020476A1 to Wahl, et. al.,.
Adjunct Materials
[0178] According to another aspect of the present invention, the fluid fabric enhancer compositions may comprise one or more of the following optional ingredients: perfume delivery systems such as encapsulated perfumes, dispersing agents, stabilizers, pH control agents, colorants, brighteners, dyes, odor control agent, cyclodextrin, solvents, soil release polymers, preservatives, antimicrobial agents, chlorine scavengers, anti-shrinkage agents, fabric crisping agents, spotting agents, anti-oxidants, anti-corrosion agents, formaldehyde scavengers as disclosed above, bodying agents, drape and form control agents, smoothness agents, static control agents, wrinkle control agents, sanitization agents, disinfecting agents, germ control agents, mold control agents, mildew control agents, antiviral agents, anti-microbials, drying agents, stain resistance agents, soil release agents, malodor control agents, fabric refreshing agents, chlorine bleach odor control agents, dye fixatives, dye transfer inhibitors, color maintenance agents, color restoration/rejuvenation agents, anti-fading agents, whiteness enhancers, anti-abrasion agents, wear resistance agents, fabric integrity agents, anti-wear agents, defoamers and anti-foaming agents, rinse aids, UV protection agents, sun fade inhibitors, insect repellents, anti-allergenic agents, enzymes, flame retardants, water proofing agents, fabric comfort agents, water conditioning agents, shrinkage resistance agents, stretch resistance agents, thickeners, chelants, electrolytes and mixtures thereof.
[0179] Deposition Aid—In one aspect, the fabric treatment composition may comprise from about 0.01% to about 10%, from about 0.05 to about 5%, or from about 0.15 to about 3% of a deposition aid. Suitable deposition aids are disclosed in, for example, U.S. patent application Ser. No. 12/080,358.
[0180] In one aspect, the deposition aid may be a cationic or amphoteric polymer. In one aspect, the deposition aid may be a cationic polymer. In one aspect, the cationic polymer may comprise a cationic acrylate such as Rheovis CDE™. Cationic polymers in general and their method of manufacture are known in the literature. In one aspect, the cationic polymer may have a cationic charge density of from about 0.005 to about 23, from about 0.01 to about 12, or from about 0.1 to about 7 milliequivalents/g, at the pH of intended use of the composition. For amine-containing polymers, wherein the charge density depends on the pH of the composition, charge density is measured at the intended use pH of the product. Such pH will generally range from about 2 to about 11, more generally from about 2.5 to about 9.5. Charge density is calculated by dividing the number of net charges per repeating unit by the molecular weight of the repeating unit. The positive charges may be located on the backbone of the polymers and/or the side chains of polymers.
[0181] One group of suitable cationic polymers includes those produced by polymerization of ethylenically unsaturated monomers using a suitable initiator or catalyst, such as those disclosed in U.S. Pat. No. 6,642,200.
[0182] Suitable polymers may be selected from the group consisting of cationic or amphoteric polysaccharide, polyethylene imine and its derivatives, and a synthetic polymer made by polymerizing one or more cationic monomers selected from the group consisting of N,N-dialkylaminoalkyl acrylate, N,N-dialkylaminoalkyl methacrylate, N,N-dialkylaminoalkyl acrylamide, N,N-dialkylaminoalkylmethacrylamide, quaternized N,N dialkylaminoalkyl acrylate quaternized N,N-dialkylaminoalkyl methacrylate, quaternized N,N-dialkylaminoalkyl acrylamide, quaternized N,N-dialkylaminoalkylmethacrylamide, Methacryloamidopropyl-pentamethyl-1,3-propylene-2-ol-ammonium dichloride, N,N,N,N′,N′,N″,N″-heptamethyl-N″-3-(1-oxo-2-methyl-2-propenyl)aminopropyl-9-oxo-8-azo-decane-1,4,10-triammonium trichloride, vinylamine and its derivatives, allylamine and its derivatives, vinyl imidazole, quaternized vinyl imidazole and diallyl dialkyl ammonium chloride and combinations thereof, and optionally a second monomer selected from the group consisting of acrylamide, N,N-dialkyl acrylamide, methacrylamide, N,N-dialkylmethacrylamide, C 1 -C 12 alkyl acrylate, C 1 -C 12 hydroxyalkyl acrylate, polyalkylene glyol acrylate, C 1 -C 12 alkyl methacrylate, C 1 -C 12 hydroxyalkyl methacrylate, polyalkylene glycol methacrylate, vinyl acetate, vinyl alcohol, vinyl formamide, vinyl acetamide, vinyl alkyl ether, vinyl pyridine, vinyl pyrrolidone, vinyl imidazole, vinyl caprolactam, and derivatives, acrylic acid, methacrylic acid, maleic acid, vinyl sulfonic acid, styrene sulfonic acid, acrylamidopropylmethane sulfonic acid (AMPS) and their salts. The polymer may optionally be branched or cross-linked by using branching and crosslinking monomers. Branching and crosslinking monomers include ethylene glycoldiacrylate divinylbenzene, and butadiene. A suitable polyethyleneinine useful herein is that sold under the tradename Lupasol® by BASF, AG, Lugwigschaefen, Germany.
[0183] In another aspect, the treatment composition may comprise an amphoteric deposition aid polymer so long as the polymer possesses a net positive charge. Said polymer may have a cationic charge density of about 0.05 to about 18 milliequivalents/g.
[0184] In another aspect, the deposition aid may be selected from the group consisting of cationic polysaccharide, polyethylene imine and its derivatives, poly(acrylamide-co-diallyldimethylammonium chloride), poly(acrylamide-methacrylamidopropyltrimethyl ammonium chloride), poly(acrylamide-co-N,N-dimethyl aminoethyl acrylate) and its quaternized derivatives, poly(acrylamide-co-N,N-dimethyl aminoethyl methacrylate) and its quaternized derivative, poly(hydroxyethylacrylate-co-dimethyl aminoethyl methacrylate), poly(hydroxpropylacrylate-co-dimethyl aminoethyl methacrylate), poly(hydroxpropylacrylate-co-methacrylamidopropyltrimethylammonium chloride), poly(acrylamide-co-diallyldimethylammonium chloride-co-acrylic acid), poly(acrylamide-methacrylamidopropyltrimethyl ammonium chloride-co-acrylic acid), poly(diallyldimethyl ammonium chloride), poly(vinylpyrrolidone-co-dimethylaminoethyl methacrylate), poly(ethyl methacrylate-co-quaternized dimethylaminoethyl methacrylate), poly(ethyl methacrylate-co-oleyl methacrylate-co-diethylaminoethyl methacrylate), poly(diallyldimethylammonium chloride-co-acrylic acid), poly(vinyl pyrrolidone-co-quaternized vinyl imidazole) and poly(acrylamide-co-Methacryloamidopropyl-pentamethyl-1,3-propylene-2-ol-ammonium dichloride), Suitable deposition aids include Polyquaternium-1, Polyquaternium-5, Polyquaternium-6, Polyquaternium-7, Polyquaternium-8, Polyquaternium-11, Polyquaternium-14, Polyquaternium-22, Polyquaternium-28, Polyquaternium-30, Polyquaternium-32 and Polyquaternium-33, as named under the International Nomenclature for Cosmetic Ingredients.
[0185] In one aspect, the deposition aid may comprise polyethyleneimine or a polyethyleneimine derivative. In another aspect, the deposition aid may comprise a cationic acrylic based polymer. In a further aspect, the deposition aid may comprise a cationic polyacrylamide. In another aspect, the deposition aid may comprise a polymer comprising polyacrylamide and polymethacrylamidoproply trimethylammonium cation. In another aspect, the deposition aid may comprise poly(acrylamide-N-dimethyl aminoethyl acrylate) and its quaternized derivatives. In this aspect, the deposition aid may be that sold under the tradename Sedipur®, available from BTC Specialty Chemicals, a BASF Group, Florham Park, N.J. In a yet further aspect, the deposition aid may comprise poly(acrylamide-co-methacrylamidopropyltrimethyl ammonium chloride). In another aspect, the deposition aid may comprise a non-acrylamide based polymer, such as that sold under the tradename Rheovis® CDE, available from Ciba Specialty Chemicals, a BASF group, Florham Park, N.J., or as disclosed in USPA 2006/0252668.
[0186] In another aspect, the deposition aid may be selected from the group consisting of cationic or amphoteric polysaccharides. In one aspect, the deposition aid may be selected from the group consisting of cationic and amphoteric cellulose ethers, cationic or amphoteric galactomanan, cationic guar gum, cationic or amphoteric starch, and combinations thereof.
[0187] Another group of suitable cationic polymers may include alkylamine-epichlorohydrin polymers which are reaction products of amines and oligoamines with epicholorohydrin, for example, those polymers listed in, for example, U.S. Pat. Nos. 6,642,200 and 6,551,986. Examples include dimethylamine-epichlorohydrin-ethylenediamine, available under the trade name Cartafix® CB and Cartafix® TSF from Clariant, Basle, Switzerland.
[0188] Another group of suitable synthetic cationic polymers may include polyamidoamine-epichlorohydrin (PAE) resins of polyalkylenepolyamine with polycarboxylic acid. The most common PAE resins are the condensation products of diethylenetriamine with adipic acid followed by a subsequent reaction with epichlorohydrin. They are available from Hercules Inc. of Wilmington Del. under the trade name Kymene™ or from BASF AG (Ludwigshafen, Germany) under the trade name Luresin™.
[0189] The cationic polymers may contain charge neutralizing anions such that the overall polymer is neutral under ambient conditions. Non-limiting examples of suitable counter ions (in addition to anionic species generated during use) include chloride, bromide, sulfate, methylsulfate, sulfonate, methylsulfonate, carbonate, bicarbonate, formate, acetate, citrate, nitrate, and mixtures thereof.
[0190] The weight-average molecular weight of the polymer may be from about 500 to about 5,000,000, or from about 1,000 to about 2,000,000, or from about 2,500 to about 1,500,000 Daltons, as determined by size exclusion chromatography relative to polyethyleneoxide standards with RI detection. In one aspect, the MW of the cationic polymer may be from about 500 to about 37,500 Daltons.
Perfume Delivery Technologies
[0191] The fluid fabric enhancer compositions may comprise one or more perfume delivery technologies that stabilize and enhance the deposition and release of perfume ingredients from treated substrate. Such perfume delivery technologies can also be used to increase the longevity of perfume release from the treated substrate. Perfume delivery technologies, methods of making certain perfume delivery technologies and the uses of such perfume delivery technologies are disclosed in US 2007/0275866 A1, US 2004/0110648 A1, US 2004/0092414 A1, 2004/0091445 A1, 2004/0087476 A1, U.S. Pat. Nos. 6,531,444, 6,024,943, 6,042,792, 6,051,540, 4,540,721, and 4,973,422.
[0192] In one aspect, the fluid fabric enhancer composition may comprise from about 0.001% to about 20%, or from about 0.01% to about 10%, or from about 0.05% to about 5%, or even from about 0.1% to about 0.5% by weight of the perfume delivery technology. In one aspect, said perfume delivery technologies may be selected from the group consisting of: perfume microcapsules, pro-perfumes, polymer particles, functionalized silicones, polymer assisted delivery, molecule assisted delivery, fiber assisted delivery, amine assisted delivery, cyclodextrins, starch encapsulated accord, zeolite and inorganic carrier, and mixtures thereof:
[0193] Perfume Microcapsules:
[0194] In one aspect, said perfume delivery technology may comprise perfume microcapsules formed by at least partially surrounding the perfume raw materials with a wall material. In one aspect, the microcapsule wall material may comprise: melamine, polyacrylamide, silicones, silica, polystyrene, polyurea, polyurethanes, polyacrylate based materials, gelatin, polyamides, and mixtures thereof. In one aspect, said melamine wall material may comprise melamine crosslinked with formaldehyde, melamine-dimethoxyethanol crosslinked with formaldehyde, and mixtures thereof. In one aspect, said polystyrene wall material may comprise polyestyrene cross-linked with divinylbenzene. In one aspect, said polyurea wall material may comprise urea crosslinked with formaldehyde, urea crosslinked with gluteraldehyde, and mixtures thereof. In one aspect, said polyacrylate based materials may comprise polyacrylate formed from methylmethacrylate/dimethylaminomethyl methacrylate, polyacrylate formed from amine acrylate and/or methacrylate and strong acid, polyacrylate formed from carboxylic acid acrylate and/or methacrylate monomer and strong base, polyacrylate formed from an amine acrylate and/or methacrylate monomer and a carboxylic acid acrylate and/or carboxylic acid methacrylate monomer, and mixtures thereof. In one aspect, the perfume microcapsule may be coated with a deposition aid, a cationic polymer, a non-ionic polymer, an anionic polymer, or mixtures thereof. Suitable polymers may be selected from the group consisting of: polyvinylformaldehyde, partially hydroxylated polyvinylformaldehyde, polyvinylamine, polyethyleneimine, ethoxylated polyethyleneimine, polyvinylalcohol, polyacrylates, and combinations thereof. Suitable deposition aids are described above and in the section titled “Deposition Aid”.
Amine Reaction Product (ARP):
[0195] For purposes of the present application, ARP is a subclass or species of PP. One may also use “reactive” polymeric amines in which the amine functionality is pre-reacted with one or more PRMs to form an amine reaction product (ARP). Typically the reactive amines are primary and/or secondary amines, and may be part of a polymer or a monomer (non-polymer). Such ARPs may also be mixed with additional PRMs to provide benefits of polymer-assisted delivery and/or amine-assisted delivery. Nonlimiting examples of polymeric amines include polymers based on polyalkylimines, such as polyethyleneimine (PEI), or polyvinylamine (PVAm). Nonlimiting examples of monomeric (non-polymeric) amines include hydroxylamines, such as 2-aminoethanol and its alkyl substituted derivatives, and aromatic amines such as anthranilates. The ARPs may be premixed with perfume or added separately in leave-on or rinse-off applications. In another aspect, a material that contains a heteroatom other than nitrogen, for example oxygen, sulfur, phosphorus or selenium, may be used as an alternative to amine compounds. In yet another aspect, the aforementioned alternative compounds can be used in combination with amine compounds. In yet another aspect, a single molecule may comprise an amine moiety and one or more of the alternative heteroatom moieties, for example, thiols, phosphines and selenols. The benefit may include improved delivery of perfume as well as controlled perfume release. Suitable ARPs as well as methods of making same can be found in USPA 2005/0003980 A1 and U.S. Pat. No. 6,413,920 B1.
Process of Making:
[0196] A process for making a fluid fabric enhancer composition, said process comprising the steps of:
a) combining the structurant premix with a dispersion, said dispersion may comprise a fabric softener active and optionally an additional active to form a fluid fabric enhancer composition; b) optionally, adjusting the pH of said fluid fabric enhancer composition such that the fluid fabric enhancer composition is at a pH at which the pH tuneable di-amido gellant is in its nonionic, viscosity building, form.
[0199] In one aspect of said process, said structurant premix may be maintained at a temperature of less than about 50° C., or even of less than about 30° C., and said process may comprise a fabric softener active feed that may be maintained at a temperature of less than about 50° C., or even at less than about 30° C.
[0200] In one aspect, the composition of the present invention can be prepared by a process comprising the steps of;
a) mixing and heating of the fabric softener active and/or other additives to form a melt; b) dispensing the melt in water; c) cooling the resulting dispersion to below the Krafft temperature of the softener active before adding other additives such as, non-ionic alkoxylated surfactants, polyols and silicone emulsion and/or other ingredients, wherein the Krafft temperature (or critical micelle temperature), is the minimum temperature at which the fabric softener active forms vesicles/micelles; d) preparing a structurant premix comprising the pH tuneable di-amido gellant, wherein the structurant premix is at a pH such that the pH tuneable di-amido gellant is in its ionic, non-viscosity building, form; e) combining the structurant premix with a dispersion, said dispersion comprising the fabric softener active and/or other additives; f) adjusting the pH of the combined fluid detergent composition as needed, such that the fluid detergent composition is at a pH at which the pH tuneable amido gellant is in its nonionic, viscosity building, form.
[0207] In one aspect, the fluid fabric enhancer compositions comprising a pH tuneable di-amido gellant may be processed such that the temperatures of the structurant premix and/or the ingredient stream are maintained below the Krafft temperature.
Test Methods:
1. Minimum Gelling Concentration (MGC)
[0208] MGC is calculated by a tube inversion method based on R. G. Weiss, P. Terech; “Molecular Gels: Materials with self-assembled fibrillar structures” 2006 springer, p 243. In order to determine the MGC, three screenings are done:
a) First screening: prepare several vials increasing the pH tuneable di-amido gellant concentration from 0.5% to 5.0 weight % in 0.5% steps, at the target pH. b) Determine in which interval the gel is formed (one inverted sample still flowing and the next one is already a strong gel). In case no gel is formed at 5%, higher concentrations are used. c) Second screening: prepare several vials increasing the pH tuneable di-amido gellant concentration in 0.1 weight % steps in the interval determined in the first screening, at the target pH. d) Determine in which interval the gel is formed (one inverted sample still flowing and the next one is already a strong gel) e) Third screening: in order to have a very precise percentage of the MGC, run a third screening in 0.025 weight % steps in the interval determined in the second screening, at the target pH. f) The Minimum Gelling Concentration (MGC) is the lowest concentration which forms a gel in the third screening (does not flow on inversion of the sample).
[0215] For each screening, samples are prepared and treated as follows: 8 mL vials (Borosilacate glass with Teflon cap, ref. B7857D, Fisher Scientific Bioblock) are filled with 2.0000±0.0005 g (KERN ALJ 120-4 analytical balance with ±0.1 mg precision) of demineralized water and/or solvent for which we want to determine the MGC. The vial is sealed with the screw cap and left for 10 minutes in an ultrasound bath (Elma Transsonic T 710 DH, 40 kHz, 9.5 L, at 25° C. and operating at 100% power) in order to disperse the solid in the liquid. Complete dissolution is then achieved by heating, using a heating gun (Bosch PHG-2), and gentle mechanical stifling of the vials. It is crucial to observe a completely clear solution. Handle vials with enhancer. While they are manufactured to resist high temperatures, a high solvent pressure may cause the vials to explode. Vials are cooled to 25° C., for 10 min in a thermostatic bath (Compatible Control Thermostats with controller CC2, D77656, Huber). Vials are inverted, left inverted for 1 minute, and then observed for which samples do not flow. After the third screening, the concentration of the sample that does not flow after this time is the MGC. For those skilled in the art, it is obvious that during heating solvent vapours may be formed, and upon cooling down the samples, these vapours can condense on top of the gel. When the vial is inverted, this condensed vapour will flow. This is discounted during the observation period. If no gels are obtained in the concentration interval, higher concentrations must be evaluated.
2. Dispenser Residue Test
[0216] The dispenser residue test is to visualize the amount of fluid fabric enhancer residue left by either dilute or concentrate fluid fabric enhancer, in a washing machine fabric enhancer dispenser after a full washing machine run. A series of 10 cumulative washes is done in the same washing machine without cleaning out the dispenser in between cycles. Before the first cycle, the washing machine fabric enhancer dispenser needs to be cleaned, removing any residue with hot water and drying the dispenser with a wipe. In between cycles the dispenser must not be cleaned. This test is performed in a Bauknecht Wash. 9850. In first place, the washing machine is loaded with ±2.65 Kg cotton ballast load, comprising 4 pillow cases, 4 tea towels, 800 grams of Muslin and 800 grams of Knitted cotton, previously pre-conditioned 4 times at 95° C. Add 150 grams of a powder detergent into the main wash detergent dispenser and 35 grams of a concentrated fabric softener (as the compositions described below) or 120 grams of a diluted fabric softener into the fabric conditioner dispenser. Start the wash cycle at 95° C., without pre-wash. Within one hour after the washing machine finishes, the residues on the dispenser are visually graded. Grading is done after 1, 5 and 10 cycles.
Grading of the Residues:
[0000]
Grade 0: No residues
Grade 1: Maximum of 3 small spread spots of about 10 mm diameter each
Grade 2: From 4 to 7 small spots of 10 mm diameter each
Grade 3: Maximum of 3 spots of about 0.5 cm each
Grade 4: From 4 to 7 small spots of 0.5 cm diameter each)
Grade 5: Thick residue with diameter from about 1 to about 3 cm diameter (more or less half of the fabric softener dispenser)
Grade 6: Thick residue with diameter from about 3 to about 6 cm diameter (more or less three quarters of the fabric softener dispenser)
Grade 7: Thick residue with diameter from about 6 to about 8 cm diameter (more or less the whole fabric softener dispenser)
Grading from about 0 to about 3 is considered acceptable.
3. Method of Measuring the Solubility of Water-Soluble Films
[0225] 5.0 grams±0.1 gram of the water-soluble film is added in a pre-weighed 400 ml beaker and 245 ml±1 ml of distilled water at 10° C. is added. This is stirred vigorously on a magnetic stirrer set at 600 rpm, for 30 minutes. Then, the mixture is filtered through a sintered-glass filter with a pore size of maximum 20 microns. The water is dried off from the collected filtrate by any conventional method, and the weight of the remaining material is determined (which is the dissolved or dispersed fraction). Then, the percentage solubility or dispersibility can be calculated.
4. Method of Measuring the Dissolution Time of Water-Soluble Films
[0226] The film is cut and mounted into a folding frame slide mount for 24 mm by 36 mm diapositive film, without glass (part number 94.000.07, supplied by Else, The Netherlands, however plastic folding frames from other suppliers may be used).
[0227] A standard 600 ml glass beaker is filled with 500 ml of city water at 10° C. and agitated using a magnetic stirring rod such that the bottom of the vortex is at the height of the 400 ml graduation mark on the beaker.
[0228] The slide mount is clipped to a vertical bar and suspended into the water, with the 36 mm side horizontal, along the diameter of the beaker, such that the edge of the slide mount is 5 mm from the beaker side, and the top of the slide mount is at the height of the 400 ml graduation mark. The stop watch is started immediately the slide mount is placed in the water, and stopped when the film fully dissolves. This time is recorded as the “film dissolution time”.
Examples
Fluid Fabric Enhancer Comprising Di-Amido Gellant
[0229] Non-limiting examples of product formulations containing di-amido gellants are summarized in the following table.
[0000]
EXAMPLES
% wt
A
B
C
D
E
F
G
H
I
J
FSA a
14
16.47
14
12
12
16.47
5
5
FSA b
3.00
FSA c
6.5
Ethanol
2.18
2.57
2.18
1.95
1.95
2.57
0.81
0.81
Isopropyl
0.33
1.22
Alcohol
Starch d
1.25
1.47
2.00
1.25
2.30
0.5
0.70
0.71
0.42
Perfume
0.75
0.6
0.75
0.37
0.60
0.37
0.6
0.37
0.37
microcapsule
Phase
0.21
0.25
0.21
0.21
0.14
0.14
Stabilizing
Polymer f
Suds
0.1
Suppressor g
Calcium
0.15
0.176
0.15
0.15
0.30
0.176
0.1-0.15
Chloride
DTPA h
0.017
0.017
0.017
0.017
0.007
0.007
0.20
0.002
0.002
Preservative
5
5
5
5
5
5
250 j
5
5
(ppm) i, j
Antifoam k
0.015
0.018
0.015
0.015
0.015
0.015
0.015
0.015
Dye
40
40
40
40
40
40
11
30-300
30
30
(ppm)
Ammonium
0.100
0.118
0.100
0.100
0.115
0.115
Chloride
HCl
1
1
1
1
1
1
1
1
1
1
Sodium
1
1
1
1
1
1
1
1
1
1
hydroxide
(6S,19S)-6,19-
0.06
0.1
0.12
0.15
0.18
0.2
0.25
diisopropyl-
4,7,18,21-
tetraoxo-
5,8,17,20-
tetraazatetracosane-
1,24-dioic
acid
(6S,23S)-6,23-
0.02
0.15
0.2
0.1
diisopropyl-
4,7,22,25-
tetraoxo-
5,8,21,24-
tetraazaoctacosane-
1,28-dioic
acid
Neat
0.8
0.7
0.9
0.5
1.2
0.5
1.1
0.6
1.0
0.9
Unencapsulated
Perfume
Deionized
Up to
Up to
Up to
Up to
Up to
Up to
Up to
Up to
Up to
Up to
Water
100
100
100
100
100
100
100
100
100
100
a N,N-di(tallowoyloxyethyl)-N,N-dimethylammonium chloride.
b Methyl bis(tallow amidoethyl)2-hydroxyethyl ammonium methyl sulfate.
c Reaction product of Fatty acid with Methyldiethanolamine in a molar ratio 1.5:1, quaternized with Methylchloride, resulting in a 1:1 molar mixture of N,N-bis(stearoyl-oxy-ethyl) N,N-dimethyl ammonium chloride and N-(stearoyl-oxy-ethyl) N,-hydroxyethyl N,N dimethyl ammonium chloride.
d Cationic high amylose maize starch available from National Starch under the trade name CATO ®.
f Copolymer of ethylene oxide and terephthalate having the formula described in U.S. Pat. No. 5,574,179 at col. 15, lines 1-5, wherein each X is methyl, each n is 40, u is 4, each R1 is essentially 1,4-phenylene moieties, each R2 is essentially ethylene, 1,2-propylene moieties, or mixtures thereof.
g SE39 from Wacker
h Diethylenetriaminepentaacetic acid.
i KATHON ® CG available from Rohm and Haas Co. “PPM” is “parts per million.”
j Gluteraldehyde
k Silicone antifoam agent available from Dow Corning Corp. under the trade name DC2310.
l Hydrophobically-modified ethoxylated urethane available from Rohm and Haas under the tradename Aculyn ™ 44.
[0230] The fluid fabric enhancers provided in this example are tested in accordance with the residue test method described above and the results are:
[0000]
A
B
C
D
E
F
G
H
I
J
Average 10 cycles
0.2
0.2
0.5
0.7
1.3
1.7
1.8
0.2
2.3
1.0
[0231] Thus, it is clear that the use of a pH tuneable di-amido gellant to give a reach impression and to improve the stability of fluid fabric enhancer composition such as perfume microcapsules, unexpectedly leaves no residues in the washing machine dispenser.
[0232] The dimensions and values disclosed herein are not to be understood as being strictly limited to the exact numerical values recited. Instead, unless otherwise specified, each such dimension is intended to mean both the recited value and a functionally equivalent range surrounding that value. For example, a dimension disclosed as “40 mm” is intended to mean “about 40 mm”.
[0233] Every document cited herein, including any cross referenced or related patent or application, is hereby incorporated herein by reference in its entirety unless expressly excluded or otherwise limited. The citation of any document is not an admission that it is prior art with respect to any invention disclosed or claimed herein or that it alone, or in any combination with any other reference or references, teaches, suggests or discloses any such invention. Further, to the extent that any meaning or definition of a term in this document conflicts with any meaning or definition of the same term in a document incorporated by reference, the meaning or definition assigned to that term in this document shall govern.
[0234] While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention. | Fluid fabric enhancer compositions comprising external structurants and processes for making and using same are provided. Such fluid fabric enhancer compositions can have a rich impression, stabilize/suspend performance ingredients such as perfume microcapsules, be easily poured/dosed and minimizes residue build up in laundry machine dispensers. In addition, such compositions have tunable rheologies. | 2 |
RELATED APPLICATION
This application is a continuation-in-part of application Ser. No. 08/171,144 filed Dec. 20, 1993 now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a catalytic converter or reactor and a process for carrying out highly exothermic reactions.
2. Description of the Prior Art
Substantial difficulties are encountered in carrying out highly exothermic reactions where reactants and/or products are temperature sensitive. For example, the catalytic liquid phase reaction of propylene and hydrogen peroxide to produce propylene oxide is a highly exothermic reaction while hydrogen peroxide decomposition is quite temperature sensitive. Thus, removal of the exothermic heat of reaction without causing excess temperature rise presents a serious problem.
Conventional reactors for exothermic reactions are usually of two types:
(1) Quench type which consist of multiple fixed beds with cold feed quench injected in between beds
(2) Tubular type in which the catalyst is placed in the tubes of a vertical shell and tube heat exchanger
If the heat of reaction is high, the first type does not provide sufficient heat removal. This can be overcome by recycling cold reactor effluent but this results in the disadvantages associated with back-mixed reactors.
The tubular reactor cost becomes prohibitive when high heats of reaction have to be removed through heat exchanger surfaces operating with a low heat transfer coefficient. There is also a temperature gradient from the center of the tube which is often detrimental to a process which requires nearly isothermal conditions.
U.S. Pat. Nos. 2,271,646 and 2,322,366 provide catalytic converters for use in catalytic cracking and the like reactions wherein the converters are divided into a series of zones and the reaction mixture from one zone is removed and externally heated or cooled before being returned to the next reaction zone. Such converters are not suitable for the effective temperature and reagent concentration control of a highly exothermic system as is achieved in accordance with the present invention.
BRIEF DESCRIPTION OF THE INVENTION
In accordance with the present invention, a catalytic converter tower is provided containing a series of separate zones each having a bed of solid catalyst contained therein. Liquid reaction mixture containing the appropriate reactants is introduced into a zone and passed at reaction conditions through the catalyst bed. The resulting reaction mixture is removed from the reactor and the exothermic heat of reaction is removed by indirect heat exchange. The great bulk of the cooled reaction mixture is recycled to the zone from which it was removed while a smaller portion is passed to the next zone and reacted in a similar fashion.
The recycle of the great bulk of the reaction mixture after cooling insures that only a modest temperature rise takes place in any one reaction zone. The provision of separate reaction zones enables close control of the reaction compositions approaching a plug flow reactor configuration.
DESCRIPTION OF THE DRAWING
The accompanying drawings, FIGS. 1-3, illustrate the improved reactor and various practices of the invention.
DETAILED DESCRIPTION
Practice of the invention is especially applicable to highly exothermic reactions such as that between propylene and hydrogen peroxide to form propylene oxide. In such a reaction, heat of reaction must be removed and the reaction temperature must be carefully controlled in order to achieve optimum results.
Referring to the attached drawing, FIG. 1, a four zone reactor 1 is illustrated. Each of the zones is provided with liquid inlet means near the upper part thereof, a packed bed of solid catalyst particles, liquid withdrawal means near the bottom of each zone, and vapor passage means permitting vapor to pass from one zone to the next; the lowest zone is not provided with the vapor passage means.
As shown in FIG. 1 and with reference to the production of propylene oxide by reaction of hydrogen peroxide and propylene, feed propylene and a hydrogen peroxide containing solution as well as recycled cooled reaction mixture containing unreacted propylene and hydrogen peroxide together with product propylene oxide is introduced into zone 2 via line 3. Net hydrogen peroxide feed is introduced into line 3 via line 4. Net propylene is introduced via lines 32 and 33 as liquid. The liquid mixture passes downwardly through packed catalyst bed 5 wherein the exothermic reaction of propylene and hydrogen peroxide to form propylene oxide takes place and there is a modest temperature increase of the mixture as a result of the reaction exotherm.
The reaction mixture passes through catalyst bed 5 into the lower section of zone 2. Risers 6 are provided permitting vapor passage downwardly to the next lower zone but preventing passage of liquid therethrough. Liquid level 7 is maintained in the lower section of zone 2 by known liquid level control means.
Liquid reaction mixture is withdrawn from zone 2 via line 8 and passes to indirect heat exchanger 10 wherein the reaction exotherm is removed and the circulating mixture is cooled to about its original temperature.
Most of the cooled mixture passes via lines 11 and 3 back to zone 2 together with the net propylene and hydrogen peroxide feed.
A minor portion of the cooled reaction mixture from zone 2 passes from cooler 10 via lines 11 and 13 to reaction zone 14 in combination with cooled recycle liquid from zone 14 and additional net liquid propylene added via lines 32 and 34.
Zone 14 is essentially similar to zone 2 with the reaction liquid passing downwardly through packed catalyst bed 15 wherein further reaction of hydrogen peroxide with propylene takes place. Risers 16 permit vapor passage therethrough and liquid level 17 is maintained in the lower section of zone 14.
Reaction liquid passes from zone 14 via line 18, to heat exchanger 19 where the reaction exotherm generated in zone 14 is removed. Most of the liquid cooled in exchanger 19 passes via lines 20 and 13 back to zone 14. A minor portion passes via lines 20 and 21 to the next reaction zone 22 together with recycled reaction mixture form zone 22 and additional net liquid propylene introduced via lines 32 and 35.
Zone 22 is similar to the preceding zones. The reaction mixture is passed downwardly through catalyst bed 23 wherein further exothermic reaction of propylene and hydrogen peroxide takes place. Risers 24 permit vapor passage therethrough and liquid level 25 is maintained in the lower section of zone 22.
Reaction liquid passes from zone 22 via line 26 to heat exchanger 27 where the reaction exotherm generated in zone 22 is removed. Most of the cooled liquid passes from exchanger via lines 28 and 21 back to zone 22. A minor portion passes via lines 28 and 29 to the next reaction zone 30.
Zone 30 is similar to the preceding zones but being the bottom zone has no risers for vapor passage. The reaction mixture passes downwardly through bed 31 of packed catalyst wherein the reaction between propylene and hydrogen peroxide is completed. Product liquid is removed via line 41. The lowest reaction zone is essentially a zone where the last generally small amount of hydrogen peroxide is reacted. Normally there is not sufficient reaction exotherm to warrant cooling and partial recycle of the liquid removed therefrom.
In the reactor illustrated in FIG. 1, zone 38 is the lowest and last reaction zone although it will be apparent that a greater or lesser number of zones can be utilized.
A small amount of propylene vapor is introduced into zone 2 via line 45 for purposes of purging any oxygen formed by hydrogen peroxide decomposition. Vapor passes through each zone through catalyst beds 5, 15, 23, and 31 via risers 6, 16, and 24 and is removed as a purge stream via line 46.
There are several advantages which are achieved through practice of the invention. By circulating large quantities of reaction liquid, temperature increase in any one zone can be kept quite small. Due to removal of the exothermic heat by cooling the liquid from each zone, close control of the reaction conditions can be achieved. By maintaining the plurality of separate zones, plug flow reactor conditions are approached and the benefits of reduced product concentrations in the earlier zones are achieved.
In general, of the liquid reaction mixture removed from each zone of the reactor, 60 to 90% is recycled after cooling with 10 to 40% moving forward to the next zone. Generally, flow in each zone is maintained at a level sufficient to limit the temperature rise in a zone to about 10° to 30° C., preferably 5° to 15° C.
A feature of the production of propylene oxide by the present invention is that the selectivity and yields of the desired propylene oxide product are improved by maintaining lower concentrations of hydrogen peroxide and product propylene oxide in the reaction mixture. This can be readily accomplished by dividing the net hydrogen peroxide feed among the several reaction zones rather than feeding all of the net hydrogen peroxide to the first zone or by adding substantial quantities of a diluent such as isopropanol, methanol or mixtures to the first reaction zone or by a combination of these procedures.
FIG. 2 illustrates a practice of the invention which is analogous to that shown in FIG. 1 except that the net hydrogen peroxide feed is divided and fed equally to the several reaction zones.
FIG. 3 illustrates a practice of the invention which is analogous to that shown in FIG. 1 except that alcohol diluent is added to the first reaction zone.
With reference to FIG. 2, the system described therein is essentially similar to that of FIG. 1 except that instead of all of the net hydrogen peroxide feed passing via lines 4 and 3 to zone 2, the net hydrogen peroxide feed is split and fed in equal amounts to zones 202, 214 and 222 via lines 204A, 204B and 204C respectively.
With reference to FIG. 3, the system described therein is essentially similar to that of FIG. 2 except that a diluent alcohol stream is added to zone 302 via lines 304D and 303.
The following examples illustrates the invention. In these examples, propylene oxide is produced by the liquid phase reaction of propylene and hydrogen peroxide in accordance with the following reaction: ##STR1## Solid titanium silicalite is employed as catalyst; see U.S. Pat. No. 5,214,168.
EXAMPLE 1
Referring to FIG. 1, net feed of hydrogen peroxide in isopropanol/water solvent are introduced via line 4 and line 3 to zone 2 with 14 mols/hr. propylene introduced via lines 32 and 33 in combination with 800 mols/hr of recycled reaction mixture via line 11. The total feed to zone 2 comprises by 9.2 mol % propylene, 7.4 mol % hydrogen peroxide, 3.1 mol % propylene oxide, 48.3 mol % isopropanol, and 32 mol % water. The liquid stream entering zone 2 is at 50° C. Purge propylene vapor is introduced into zone 2 via line 45 at the rate of 1 mol/hr.
The liquid passes through catalyst bed 5 wherein propylene and hydrogen peroxide react in accordance with the above equation. The liquid temperature is increased to 58° C. as a result of the reaction exotherm.
The liquid reaction mixture comprised of 8.8 mol % propylene, 7 mol % hydrogen peroxide, 3.5 mol % propylene oxide, 48.2 mol % isopropanol, and 32.5 mol % water passes at the rate of 914 mols/hr from zone 2 via line 8 and is cooled to 50° C. in exchanger 10.
About 800 mols/hr of the cooled mixture is recycled via lines 11 and 3 to zone 2. About 114 mols/hr of the cooled liquid passes via lines 11 and 13 to the next reaction zone 14 together with 800 mols/hr of cooled recycle reaction liquid via line 20 and 4 mols/hr. liquid propylene via lines 32 and 34. The total liquid feed to zone 14 comprises 8.9 mol % propylene, 3.9 mol % hydrogen peroxide, 6.3 mol % propylene oxide, 46.6 mol % isopropanol, and 34.3 mol % water. Temperature of the liquid introduced to zone 14 is 50° C.
In zone 14, the reaction liquid passes through catalyst bed 15 where further reaction in accordance with the above equation takes place. Liquid temperature increases to 58° C. as a result of the reaction exotherm.
Reaction liquid passes from zone 14 via line 18 to exchanger 19 at the rate of 918 mols/hr. This liquid comprises 8.5 mol % propylene, 3.5 mol % hydrogen peroxide, 6.7 mol % propylene oxide, 46.5 mol % isopropanol, and 34.8 mol % water. The liquid is cooled to 50° C. in exchanger 19.
About 800 mols/hr of the cooled mixture is recycled via lines 20 and 13 to zone 14. About 118 mols/hr of the cooled liquid passes via lines 20 and 21 to the next reaction zone 22 together with 800 mols/hr of cooled recycle reaction liquid via line 28 and 4 mols/hr. liquid propylene via lines 32 and 35. The total liquid to zone 22 comprises 8.7 mol % propylene, 0.4 mol % hydrogen peroxide, 9.4 mol % propylene oxide, 45.1 mol % isopropanol, and 36.4 mol % water. Temperature of the liquid introduced to zone 22 is 50° C.
In zone 22, the reaction liquid passes through catalyst bed 23 where further reaction is accordance with the above equation takes place. Liquid temperature increase to 58° C. as a result of the reaction exotherm.
Reaction liquid passes from zone 22 via line 26 to exchanger 27 at the rate of 922 mols/hr. This liquid comprises 8.2 mol % propylene, 0 mol % hydrogen peroxide, 9.9 mol % propylene oxide, 45 mol % isopropanol, and 36.9 mol % water. The liquid is cooled to 50° C. in exchanger 27.
About 800 mols/hr of the cooled mixture is recycled via lines 28 and 21 to zone 22. About 122 mols/hr. of the cooled liquid passes via lines 28 and 29 to the last reaction zone 30.
In zone 30, the reaction liquid passes through catalyst bed 31 where the remaining small reaction takes place. Liquid temperature increase is small, less than 8° C. as a result of the reaction exotherm and about 122 mols/hr. of liquid product is recovered via line 41.
Purge vapor in amount of 1.2 mols/hr. is removed via line 46 and comprises 84 mol % propylene, 8 mol % water and isopropanol, and 8 mol % oxygen.
The overall yield of propylene oxide based on hydrogen peroxide is 90%. This compares with a yield of about 80% which is achieved using conventional tubular reactors wherein the temperature rise in the catalyst exceeds 15° C.
EXAMPLE 2
Referring to FIG. 2, net feed of hydrogen peroxide in isopropanol/water solvent is introduced at the rate of 100 mols/hr via line 204. The feed composition comprises 33 mol % water, 55 mol % isopropanol and 12 mol % hydrogen peroxide. This net hydrogen peroxide feed is divided with 34 mols/hr passing via lines 204A and 203 to zone 202, 33 mols/hr passing via lines 204B, 220 and 213 to zone 214, and 33 mols/hr passing via lines 204C, 228 and 221 to zone 222.
The 34 mols/hr of hydrogen peroxide feed is combined with feed propylene introduced via line 232 and with recycle reaction mixture via line 211 to form a feed mixture to zone 202 via line 203 of 861 mols/hr comprised of 241 mols/hr water, 331 mols/hr isopropanol, 18 mols/hr hydrogen peroxide, 228 mols/hr propylene and 41 mols/hr propylene oxide. This mixture is fed to zone 202 at 54.4° C. and 240 psia.
The liquid passes through catalyst bed 205 wherein propylene and hydrogen peroxide react in accordance with the above equation. The liquid temperature is increased to 60° C. as a result of the reaction exotherm.
The liquid reaction mixture comprised of 25.1 mol % propylene, 1.68 mol % hydrogen peroxide, 5.17 mol % propylene oxide, 38.9 mol % isopropanol, and 28.7 mol % water passes at the rate of 849 mols/hr from zone 202 via line 208 and is cooled to 54.4° C. in exchanger 10.
About 800 mols/hr of the cooled mixture is recycled via lines 211 and 203 to zone 202. About 49 mols/hr of the cooled liquid passes via lines 211 and 213 to the next reaction zone 214 together with 800 mols/hr of cooled recycle reaction liquid via line 220, 25 mols/hr liquid propylene via lines 232 and 234, and 33 mols/hr of the hydrogen peroxide feed. The total liquid feed to zone 214 comprises 26.1 mol % propylene, 1.82 mol % hydrogen peroxide, 5.5 mol % propylene oxide, 37.8 mol % isopropanol, and 28.3 mol % water. Temperature of the liquid introduced to zone 14 is 54.4° C.
In zone 214, the reaction liquid passes through catalyst bed 215 where further reaction in accordance with the above equation takes place. Liquid temperature increases to 60° C. as a result of the reaction exotherm.
Reaction liquid passes from zone 214 via line 218 to exchanger 219 at the rate of 896 mols/hr. This liquid comprises 24.9 mol % propylene, 1.45 mol % hydrogen peroxide, 5.9 mol % propylene oxide, 38.3 mol % isopropanol, and 29.1 mol % water. The liquid is cooled to 54.4° C. in exchanger 219.
About 800 mols/hr of the cooled mixture is recycled via lines 220 and 213 to zone 214. About 96 mols/hr of the cooled liquid passes via lines 220 and 221 to the next reaction zone 222 together with 800 mols/hr of cooled recycle reaction liquid via line 228, 25 mols/hr liquid propylene via lines 232 and 235, and 33 mols/hr of the hydrogen peroxide feed. The total liquid to zone 222 comprises 26.0 mol % propylene, 1.65 mol % hydrogen peroxide, 6.0 mol % propylene oxide, 37.5 mol % isopropanol, and 28.5 mol % water. Temperature of the liquid introduced to zone 222 is 54.4° C.
In zone 222, the reaction liquid passes through catalyst bed 223 where further reaction is accordance with the above equation takes place. Liquid temperature increases to 60° C. as a result of the reaction exotherm.
Reaction liquid passes from zone 222 via line 226 to exchanger 227 at the rate of 943.7 mols/hr. This liquid comprises 24.9 mol % propylene, 1.28 mol % hydrogen peroxide, 6.4 mol % propylene oxide, 37.9 mol % isopropanol, and 29.1 mol % water. The liquid is cooled to 54.4° C. in exchanger 227.
About 800 mols/hr of the cooled mixture is recycled via lines 228 and 221 to zone 222. About 143.7 mols/hr. of the cooled liquid passes via lines 228 and 219 to the last reaction zone 330.
In zone 230, the reaction liquid passes through catalyst bed 231 where the remaining small reaction takes place. Liquid temperature increase is small, less than 8° C. as a result of the reaction exotherm and about 128 mols/hr of liquid product is recovered via line 241.
Purge vapor in amount of 48 mols/hr is removed via line 246 and comprises 92.6 mol % propylene, 0.6 mol % oxygen, 3.8 mol % water and isopropanol, and 3 mol % propylene oxide; this stream is further treated for propylene and propylene oxide recovery (not shown).
The overall yield of propylene oxide based on hydrogen peroxide is 90.8%. This compares with a yield of about 80% which is achieved using conventional tubular reactors wherein the temperature rise in the catalyst exceeds 15° C. The yield is also higher than that is Example 1 due to the separate introduction of hydrogen peroxide feed into the separate zones.
EXAMPLE 3
Referring to FIG. 3, the net hydrogen peroxide composition and feed rate is the same as for Example 2. The net hydrogen peroxide feed passes at the rate of 34 mols/hr via lines 304A and 303 to zone 302, at the rate of 33 mols/hr via lines 304B and 313 to zone 314, and at the rate of 33 mols/hr via lines 304C, 328 and 321 to zone 322. Isopropanol diluent is fed via lines 304D and 303 to zone 302 at the rate of 100 mols/hr.
The 34 mols/hr of hydrogen peroxide feed and 100 mols/hr of isopropanol are combined with feed propylene introduced via line 332 and with recycle reaction mixture via line 311 to form a feed mixture to zone 302 via line 303 of 806 mols/hr comprised of 54.1 mols/hr water, 464.5 mols/hr isopropanol, 7.1 mols/hr hydrogen peroxide, 271.2 mols/hr propylene and 8.2 mols/hr propylene oxide. This mixture is fed to zone 302 at 54.4° C. and 240 psia.
The liquid passes through catalyst bed 305 wherein propylene and hydrogen peroxide react in accordance with the above equation. The liquid temperature is increased to 60° C. as a result of the reaction exotherm.
The liquid reaction mixture comprised of 33.3 mol % propylene, 0.5 mol % hydrogen peroxide, 1.35 mol % propylene oxide, 57.6 mol % isopropanol, and 7.1 mol % water passes at the rate of 806 mols/hr from zone 302 via line 308 and is cooled to 54.4° C. in exchanger 310.
About 600 mols/hr of the cooled mixture is recycled via lines 311 and 303 to zone 302. About 206 mols/hr of the cooled liquid passes via lines 211 and 213 to the next reaction zone 214 together with 600 mols/hr of cooled recycle reaction liquid via line 220 and 25 mols/hr liquid propylene via lines 332 and 334, and 33 mols/hr of the hydrogen peroxide feed via line 304B. The total liquid feed to zone 314 comprises 34.2 mol % propylene, 1.03 mol % hydrogen peroxide, 1.9 mol % propylene oxide, 52.2 mol % isopropanol, and 10.5 mol % water. Temperature of the liquid introduced to zone 14 is 54.4° C.
In zone 314, the reaction liquid passes through catalyst bed 315 where further reaction in accordance with the above equation takes place. Liquid temperature increases to 60° C. as a result of the reaction exotherm.
Reaction liquid passes from zone 314 via line 318 to exchanger 319 at the rate of 860.9 mols/hr. This liquid comprises 33.6 mol % propylene, 0.65 mol % hydrogen peroxide, 2.24 mol % propylene oxide, 52.4 mol % isopropanol, and 10.9 mol % water. The liquid is cooled to 54.4° C. in exchanger 319.
About 600 mols/hr of the cooled mixture is recycled via lines 320 and 313 to zone 314. About 260.9 mols/hr of the cooled liquid passes via lines 320 and 321 to the next reaction zone 322 together with 600 mols/hr of cooled recycle reaction liquid via line 328, 25 mols/hr liquid propylene via lines 332 and 335, and 33 mols/hr of the hydrogen peroxide feed via line 304C. The total liquid to zone 322 comprises 33.2 mol % propylene, 1.04 mol % hydrogen peroxide, 2.54 mol % propylene oxide, 49.76 mol % isopropanol, and 13.32 mol % water. Temperature of the liquid introduced to zone 22 is 54.4° C.
In zone 322, the reaction liquid passes through catalyst bed 323 where further reaction is accordance with the above equation takes place. Liquid temperature increases to 60° C. as a result of the reaction exotherm.
Reaction liquid passes from zone 322 via line 326 to exchanger 327 at the rate of 908.2 mols/hr. This liquid comprises 32.1 mol % propylene, 0.68 mol % hydrogen peroxide, 2.9 mol % propylene oxide, 50.32 mol % isopropanol, and 13.84 mol % water. The liquid is cooled to 54.4° C. in exchanger 327.
About 600 mols/hr of the cooled mixture is recycled via lines 328 and 321 to zone 322. About 308 mols/hr. of the cooled liquid passes via lines 328 and 329 to the last reaction zone 330.
In zone 330, the reaction liquid passes through catalyst bed 331 where the remaining small reaction takes place. Liquid temperature increase is small, less than 8° C. as a result of the reaction exotherm and about 315 mols/hr. of liquid product is recovered via line 341.
Purge vapor in amount of 5 mols/hr. is removed via line 346 and comprises 92 mol % propylene, 4 mol % water and isopropanol, and 4 mol % oxygen.
The overall yield of propylene oxide based on hydrogen peroxide is 92%. This compares with a yield of about 80% which is achieved using conventional tubular reactors wherein the temperature rise in the catalyst exceeds 15° C. The yield is higher than that for Example 2 due to the lower concentrations of propylene oxide and hydrogen peroxide in the reaction zones. | A reactor is provided for carrying out highly exothermic reaction between liquids such as hydrogen peroxide and propylene. The reactor is made up of a series of separate zones containing a packed bed of solid catalyst; liquid from each zone is cooled with the main portion recycled to the same zone and a minor portion passing to the next successive zone. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present patent application/patent claims the benefit of priority of co-pending U.S. Provisional Patent Application No. 62/114,655, filed on Feb. 11, 2015, and entitled “FULL-CORE FITNESS MACHINE,” the contents of which are incorporated in full by reference herein.
FIELD OF THE INVENTION
[0002] The present invention provides a novel fitness machine that is intended to promote the strengthening of multiple areas of the body at one time, providing a more holistic approach to strength conditioning and overall health. The principles of the present invention can be applied to not only general exercise, but to strength training for athletes, as well as therapeutic applications. The present invention promotes physiological balance, strengthening the body core from head to feet in 360 degrees around the body.
BACKGROUND OF THE INVENTION
[0003] Many forms of weight lifting and other physical training concentrate on specific muscle groups. If one is not careful to balance their training, this can lead to muscular imbalance. For example, doing push-ups regularly without balancing them with back exercises can lead to an imbalance in upper body strength between the chest and back, which can lead to postural problems and other issues. Similar problems exist with doing crunches and other exercises focused on the abdominal muscles without balancing them with lower back exercises.
[0004] Participants in regular exercise may tend to over-emphasize one area of the body, while neglecting other areas of the body, due to certain preferences, more recognizable results, and/or other factors. For example, the bench press, which is very popular, focuses on a limited set of muscles, while ignoring others, due simply to the “one degree of freedom” motion (i.e., up and down only) that works the triceps, deltoid, and pectoral muscles, but largely ignores the trapezius, rhomboid, and latissimus dorsi muscles, along with most of the muscles along the side of the abdomen, to name a few.
[0005] Thus, the present invention provides a methodology for ensuring 360 degrees of physical exercise and strengthening by providing a continuous and changing vector of resistance loading. Rather than having one degree of freedom (in the case of the bench press, for example), where the resistance force is always downward from the chest to the back, the present invention provides a force whose direction (vector) constantly changes in infinitesimally small angles to provide a second, and potentially a third, degree of freedom. The benefits of this functionality can range from better balance and posture to therapeutic benefits. For example, 360-degree strengthening of the neck area can help substantially with concussion related injuries, recovery, and prevention.
BRIEF SUMMARY OF THE INVENTION
[0006] Thus, the present invention provides a machine and method for working not only those muscle groups that are addressed by traditional weight lifting, but instead addresses the full 360-degree core of the body in a continually varying motion, which results in a rotary force vector that works every muscle around the body.
[0007] In one exemplary embodiment, the present invention provides a fitness machine, including: a frame structure; a spanning bar rotatably coupled to the frame structure, wherein the spanning bar selectively rotates about a central axis; a gripping bar coupled to the spanning bar; and a retention mechanism coupled to the spanning bar; wherein, when a user grasps the gripping bar with his or her hands and puts his or her feet in the retention mechanism and the spanning bar is selectively rotated about the central axis, the user is also rotated about the central axis. Optionally, the spanning bar selectively rotates about the central axis by operation of an electric motor coupled to the spanning bar. Optionally, the spanning bar also selectively rotates about a secondary axis that is offset from the central axis. Optionally, the gripping bar is translatable along a length of the spanning bar. Optionally, the gripping bar is rotatable with respect to the spanning bar. Optionally, the fitness machine also includes a pair of rotatable hand grips coupled to the gripping bar by which the user selectively grasps the gripping bar. The spanning bar is disposed at an angle with respect to the frame structure such that a center of gravity of the user substantially coincides with the central axis when the user grasps the gripping bar with his or her hands and puts his or her feet in the retention mechanism.
[0008] In another exemplary embodiment, the present invention provides a fitness method, including: providing a frame structure; providing a spanning bar rotatably coupled to the frame structure, wherein the spanning bar selectively rotates about a central axis; providing a gripping bar coupled to the spanning bar; and providing a retention mechanism coupled to the spanning bar; wherein, when a user grasps the gripping bar with his or her hands and puts his or her feet in the retention mechanism and the spanning bar is selectively rotated about the central axis, the user is also rotated about the central axis. Optionally, the spanning bar selectively rotates about the central axis by operation of an electric motor coupled to the spanning bar. Optionally, the spanning bar also selectively rotates about a secondary access that is offset from the central axis. Optionally, the gripping bar is translatable along a length of the spanning bar. Optionally, the gripping bar is rotatable with respect to the spanning bar. Optionally, the fitness method also includes providing a pair of rotatable hand grips coupled to the gripping bar by which the user selectively grasps the gripping bar. The spanning bar is disposed at an angle with respect to the frame structure such that a center of gravity of the user substantially coincides with the central axis when the user grasps the gripping bar with his or her hands and puts his or her feet in the retention mechanism.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The present invention is illustrated and described herein with reference to the various drawings, in which like reference numbers are used to denote like machine components/method steps, as appropriate, and in which:
[0010] FIG. 1 is a series of schematic diagrams illustrating the operation of the motorized full-core fitness machine of the present invention, highlighting the rotation of a user from a push-up configuration to a pull-up configuration and back again;
[0011] FIG. 2 is a series of schematic diagrams illustrating the continuously varying force vector generated by the full-core fitness machine of the present invention, again highlighting the rotation of the user from a push-up configuration to a pull-up configuration and back again;
[0012] FIG. 3 is another series of schematic diagrams illustrating the operation of the motorized full-core fitness machine of the present invention, highlighting the optional use of an adjustable spanning bar and a translatable and/or rotatable gripping bar;
[0013] FIG. 4 is a series of schematic diagrams illustrating the operation of the non-motorized full-core fitness machine of the present invention, highlighting the rotation of a user from a push-up configuration to a pull-up configuration and back again;
[0014] FIG. 5 is a series of schematic diagrams illustrating the operation of a multi-axis fitness machine of the present invention;
[0015] FIG. 6 is a series of schematic diagrams illustrating the operation of the fitness machine of the present invention utilizing an auxiliary frame structure and assistive supports, such as springs or tension members;
[0016] FIG. 7 is a perspective view illustrating one specific embodiment of the full-core fitness machine of the present invention;
[0017] FIG. 8 is another perspective view illustrating one specific embodiment of the full-core fitness machine of the present invention;
[0018] FIG. 9 is a perspective view illustrating another specific embodiment of the full-core fitness machine of the present invention;
[0019] FIG. 10 is another perspective view illustrating another specific embodiment of the full-core fitness machine of the present invention; and
[0020] FIG. 11 is a partial perspective view illustrating another specific embodiment of the full-core fitness machine of the present invention, highlighting the rotating hand grips thereof.
DETAILED DESCRIPTION OF THE INVENTION
[0021] Again, the present invention provides a machine and method for working not only those muscle groups that are addressed by traditional weight lifting, but instead addresses the full 360-degree core of the body in a continually varying motion, which results in a rotary force vector that works every muscle around the body.
[0022] Referring now specifically to FIG. 1 , the full-core fitness machine 10 includes a spanning bar 12 with an attached gripping bar 14 . The proximal end of the spanning bar 12 includes a vertical rotation bar 16 , and the distal end of the spanning bar 12 includes a foot retention mechanism 18 . A user places his or her feet securely in the foot retention mechanism 20 and grasps the gripping bar 14 with his or her hands, thereby placing the user in a push-up configuration, for example. A pair of rotation shafts 20 are coupled to the vertical rotation bar 16 and the foot retention mechanism 18 such that the spanning bar 12 and user can be rotated about a rotational axis 22 of the machine 10 . In this exemplary embodiment, this rotational axis 22 is parallel, or nearly parallel, to the ground. The spanning bar 12 orients the user such that his or her general center of gravity is located about the rotational axis 22 , or the overall center of gravity (including both that of the rotational components and the user) is located about the rotational axis 22 . The pair of rotation shafts 20 couple the spanning bar 12 to a suitable frame structure 24 . An electric motor 26 and optional counterweight 28 are coupled to the vertical rotation bar 16 such that the spanning bar 12 and user can be rotated about the rotational axis 22 in a smooth, controlled manner. In this configuration, the electric motor 26 rotates the spanning bar 12 slowly about the rotational axis 22 while the user attempts to hold position with his or her body. Initially, the user may be in a typical push-up configuration, facing downward. In this position, the user will exercise the triceps, chest, stomach, back of neck, and so on. As the user is rotated to the side, he or she begins using the triceps on the lower arm and biceps on the upper arm, as well as shoulder, back, side neck, and side abdomen. When upside down, in a pull-up configuration, the user uses the back, back shoulder, lower back, buttocks, and front neck. This is illustrated in the various positions of FIG. 1 , showing one complete revolution of the user. The use of the machine of the present invention enables the balanced development of multiple muscle groups without changing machines.
[0023] FIG. 2 is a series of schematic diagrams illustrating the continuously varying force vector generated by the full-core fitness machine 10 ( FIG. 1 ) of the present invention, again highlighting the rotation of the user from a push-up configuration to a pull-up configuration and back again.
[0024] Referring now specifically to FIG. 3 , in another exemplary embodiment, the spanning bar 12 may be adjustable (in vertical displacement and/or slope) to lower or raise the gripping bar 14 , such that the “static” position of the user's arms changes, working the muscle group in a different range. Similarly, the gripping bar 14 can be rotated (when viewed from the top) to work yet another muscle group, and/or it can be shifted fore and aft to work yet another muscle group.
[0025] Referring now specifically to FIG. 4 , in a further exemplary embodiment, the spanning bar 12 can be free-spinning (or slightly damped or otherwise controlled), rather than motorized, in such a way that when the user changes the position of his center of gravity from a neutral position, it instigates rotating movement. This movement provides more of a dynamic workout, while working the muscle groups through ranges of motion, rather than isometric (i.e., static) exercises. The user controls the rate of rotation by carefully controlling the position of his or her center of gravity. This element adds a degree of control necessary to operate the machine 10 , such that it does not rotate too quickly. Specifically, FIG. 4 illustrates the user in a neutral position; instigating rotation with a raised center of gravity; and, once upside down, pulling himself or herself upward using the back muscles to again raise the center of gravity above the axis of rotation, thereby instigating or continuing rotational motion.
[0026] Referring now specifically to FIG. 5 , in a still further exemplary embodiment, the frame structure 24 can be rotatably coupled to a suitable secondary frame structure 30 such that multiple rotating axes (providing multiple rotational orientations) may be imparted to the spanning bar 12 and user, thereby working more muscle groups in more directions.
[0027] Referring now specifically to FIG. 6 , in a still further exemplary embodiment, an auxiliary frame structure 32 and assistive devices 34 can be added to aid the user in difficult orientations, or if the user is a novice. For example, springs are shown in FIG. 6 to help to support the weight of the user when upside down, thereby assisting in a vertical push-up or the like. Side supports and/or other assistive devices may be added as well.
[0028] Any of these configurations can be used in conjunction with weight belts to augment training in certain areas of the body. For example, weights may be added about the waist to strengthen core muscles (i.e., abs, back, and sides about the abdomen). A weighted headband may be used to augment neck strengthening in 360 degrees, an exercise that may be used to significantly reduce the risk of concussions, for example.
[0029] The machine(s) of the present invention may be used not only for physical training and conditioning, but also for medical and physical therapy purposes. For example, concussions are known to be reduced through neck strengthening exercises. These devices can be used by athletes to reduce the likelihood of concussions. The use of assistive aids can help a patient gradually reach strength levels without the risk of dropping free weights, etc.
[0030] Referring now specifically to FIGS. 7 and 8 , in more detail, the full-core fitness machine 10 includes a tubular-steel spanning bar 12 or the like with an attached tubular-steel gripping bar 14 or the like. The gripping bar 14 is translatable along a portion of the length of the spanning bar 12 , and is locked into place by means of a locking peg and series of holes 36 or the like. The proximal end of the spanning bar 12 includes a tubular-steel vertical rotation bar 16 or the like, and the distal end of the spanning bar 12 includes a foot retention mechanism 18 , such as a foot platform 38 and plurality of padded foot pegs 40 or the like. It will be readily apparent to those of ordinary skill in the art that other configurations can be used to perform the functions of these components equally. A user places his or her feet securely in the foot retention mechanism 20 and grasps the gripping bar 14 with his or her hands, thereby placing the user in a push-up configuration, for example. A pair of rotation shafts/bearings 20 or the like are coupled to the vertical rotation bar 16 and the foot retention mechanism 18 such that the spanning bar 12 and user can be rotated about a rotational axis 22 of the machine 10 . In this exemplary embodiment, this rotational axis 22 is parallel, or nearly parallel, to the ground. The spanning bar 12 orients the user such that his or her general center of gravity is located about the rotational axis 22 , or the overall center of gravity (including both that of the rotational components and the user) is located about the rotational axis 22 . The pair of rotation shafts 20 couple the spanning bar 12 to a suitable frame structure 24 . In this exemplary embodiment, the frame structure 24 includes any combination of frame members 42 that are suitable for stably supporting the various components and user. The electric motor 26 ( FIG. 1 ) and optional counterweight 28 ( FIG. 1 ) are coupled to the vertical rotation bar 16 such that the spanning bar 12 and user can be rotated about the rotational axis 22 is a smooth, controlled manner. In this configuration, the electric motor 26 rotates the spanning bar 12 slowly about the rotational axis 22 while the user attempts to hold position with his or her body. The electric motor 26 may be coupled to a gear 44 ( FIG. 1 ) or the like associated with the spanning bar 12 and/or the proximal rotation shaft 20 via a pulley 46 ( FIG. 1 ) or the like. Initially, the user may be in a typical push-up configuration, facing downward. In this position, the user will exercise the triceps, chest, stomach, back of neck, and so on. As the user is rotated to the side, he or she begins using the triceps on the lower arm and biceps on the upper arm, as well as shoulder, back, side neck, and side abdomen. When upside down, in a pull-up configuration, the user uses the back, back shoulder, lower back, buttocks, and front neck. Again, the use of the machine of the present invention enables the balanced development of multiple muscle groups without changing machines.
[0031] Referring now specifically to FIGS. 9-11 , in more alternative detail, the full-core fitness machine 10 includes a tubular-steel spanning bar 12 or the like with an attached tubular-steel gripping bar 14 or the like. The gripping bar 14 is translatable along a portion of the length of the spanning bar 12 , and is locked into place by means of a locking peg and series of holes 36 or the like. In this exemplary embodiment, the gripping bar 14 includes a plurality of members arranged in a diamond shape, to which rotating hand grips 50 are coupled. It will be readily apparent to those of ordinary skill in the art that other configurations can be used to perform the functions of these components equally. The proximal end of the spanning bar 12 includes a tubular-steel vertical rotation bar 16 or the like, and the distal end of the spanning bar 12 includes a foot retention mechanism 18 , such as a foot platform 38 and plurality of padded foot pegs 40 or the like. It will be readily apparent to those of ordinary skill in the art that other configurations can be used to perform the functions of these components equally. A user places his or her feet securely in the foot retention mechanism 20 and grasps the gripping bar 14 with his or her hands, thereby placing the user in a push-up configuration, for example. A pair of rotation shafts/bearings 20 or the like are coupled to the vertical rotation bar 16 and the foot retention mechanism 18 such that the spanning bar 12 and user can be rotated about a rotational axis 22 of the machine 10 . In this exemplary embodiment, this rotational axis 22 is parallel, or nearly parallel, to the ground. The spanning bar 12 orients the user such that his or her general center of gravity is located about the rotational axis 22 , or the overall center of gravity (including both that of the rotational components and the user) is located about the rotational axis 22 . The pair of rotation shafts 20 couple the spanning bar 12 to a suitable frame structure 24 . In this exemplary embodiment, the frame structure 24 includes any combination of frame members 42 that are suitable for stably supporting the various components and user. The electric motor 26 ( FIG. 1 ) and optional counterweight 28 ( FIG. 1 ) are coupled to the vertical rotation bar 16 such that the spanning bar 12 and user can be rotated about the rotational axis 22 is a smooth, controlled manner. In this configuration, the electric motor 26 rotates the spanning bar 12 slowly about the rotational axis 22 while the user attempts to hold position with his or her body. The electric motor 26 may be coupled to a gear 44 ( FIG. 1 ) or the like associated with the spanning bar 12 and/or the proximal rotation shaft 20 via a pulley 46 ( FIG. 1 ) or the like. Initially, the user may be in a typical push-up configuration, facing downward. In this position, the user will exercise the triceps, chest, stomach, back of neck, and so on. As the user is rotated to the side, he or she begins using the triceps on the lower arm and biceps on the upper arm, as well as shoulder, back, side neck, and side abdomen. When upside down, in a pull-up configuration, the user uses the back, back shoulder, lower back, buttocks, and front neck. Again, the use of the machine of the present invention enables the balanced development of multiple muscle groups without changing machines.
[0032] Although the present invention is illustrated and described herein with reference to preferred embodiments and specific examples thereof, it will be readily apparent to those of ordinary skill in the art that other embodiments and examples may perform similar functions and/or achieve like results. All such equivalent embodiments and examples are within the spirit and scope of the present invention, are contemplated thereby, and are intended to be covered by the following non-limiting claims. | A fitness machine, including: a frame structure; a spanning bar rotatably coupled to the frame structure, wherein the spanning bar selectively rotates about a central axis; a gripping bar coupled to the spanning bar; and a retention mechanism coupled to the spanning bar; wherein, when a user grasps the gripping bar with his or her hands and puts his or her feet in the retention mechanism and the spanning bar is selectively rotated about the central axis, the user is also rotated about the central axis. Optionally, the spanning bar selectively rotates about the central axis by operation of an electric motor coupled to the spanning bar. Optionally, the spanning bar also selectively rotates about a secondary access that is offset from the central axis. Optionally, the gripping bar is translatable/rotatable with respect to the spanning bar. The spanning bar is disposed at an angle with respect to the frame structure such that a center of gravity of the user substantially coincides with the central axis. | 0 |
FIELD OF THE INVENTION
[0001] The present invention relates to a fluid sample separation device, and in particular to a disk-based fluid sample separation device that selectively allows a fluid sample contained in a sample storage reservoir to flow to a sample processing reservoir through the control of air vent and being subjected to a rotating motion.
BACKGROUND OF THE INVENTION
[0002] Techniques for fluid sample separation are of wide applications, such as separation of cells, separation of fetal cells, cell separation for whole blood samples, and separation of endothelial colony forming cells (ECFC) contained in umbilical cord blood (UCB).
[0003] For example, detection and quantification of cancer cells or rare cells present in body fluids are regarded as a potential indicator for clinical diagnoses, prognostication, and biomedicine research. For example, circulating tumor cells (CTC) are rare in the blood of patients with metastatic cancer, and it is possible to monitor the response of CTC to adjuvant therapy. Such rear cells must be first separated from the body fluids, before detection and quantification of these rare cells can be made. For such a purpose, various cell techniques have been developed.
[0004] The cell separation techniques that are commonly used includes fluorescence activated cell separation (FACS), dielectrophoresis (DEP) cell separation, separation techniques that employ massively parallel microfabricated sieving devices, magnetically activated cell separation (MACS), and other techniques that uses optics and acoustics. Among these cell separation techniques, FACS and MACS are most often used.
[0005] Although it is often used, FACS is disadvantageous in respect of high cost, difficulty in disinfection, and consuming a great amount of sample in the operation thereof. Contrary to FACS, MACS is efficient to obtain a major quantity of target cells in a short period with a reduced consumption of sample. However, these cells must be transferred to a slide or an observation platform before they can be observed with a microscope. Such a process of transfer often leads to a great loss of cells.
[0006] Since MACS shows advantages in respect of high throughput, high performance, and simplified facility, it is often adopted in separation of fluid samples. Using immune cells to separate a desired component from a blood sample and the operation of immunofluorescence require multiple samples and manually-operated transfer, so that the result of detection is heavily dependent upon the skill of an operator, making it not fit for industrial use.
SUMMARY OF THE INVENTION
[0007] In view of the above description of the conventional techniques, it is a major issue for this field to provide a fluid sample separation technique that realizes high throughput of cell selection, easy operation, low cost, simple facility, and excellent sensitivity and reliability.
[0008] Thus, an objective of the present invention is to provide a disk based fluid sample separation device, which is of low cost, is easy for detection and observation, and has reduced cell loss, and is applicable to separate a labeled component from a fluid sample.
[0009] Another objective of the present invention is to provide a disk based fluid sample separation device that is operated to selectively conduct a fluid sample contained in a sample storage reservoir to a sample processing reservoir by means of control realized by an air vent and rotary motion.
[0010] A further objective of the present invention is to provide a disk based fluid sample separation device that is operated to separate, in a fluid sample, at least two types of cells, which are respectively labeled and not labeled with the immunomagnetic beads.
[0011] The solution adopted in the present invention to achieve the above objectives is a microfluidic disk that forms therein a flow channel pattern. The flow channel pattern comprises at least one air vent. A sealing cover is set on a top surface of the microfluidic disk. The sealing cover forms at least one air passage. The sealing cover is rotatable with respect to the microfluidic disk between a first position, where the air passage of the sealing cover communicates the air vent of the flow channel pattern, and a second position, where the sealing cover closes the air vent of the flow channel pattern. The flow channel pattern comprises a sample storage reservoir, at least one sample processing reservoir, and a communication channel communicating between the sample storage reservoir and the sample processing reservoir. The sealing cover is operable through manual rotation or electrically-driven rotation to have the air passage of the sealing cover to align or close the air vent of a selected sample storage reservoir. In an embodiment of the present invention, the air vent of the sealing cover is replaced by a solenoid-controlled air vent structure.
[0012] In a preferred embodiment of the present invention, at least one magnetic unit is set on a top of the sealing cover at a location corresponding to the sample processing reservoir of the microfluidic disk for providing a uniform magnetic force of predetermined magnitude on the sample processing reservoir.
[0013] When the present invention is applied to separation of magnetically-labeled components contained in a fluid sample, it is capable of capturing all the magnetically-labeled components in whole blood cells. Further, the disk-based fluid sample separation device according to the present invention can be manufactured with a simple process, which can be carried out with laser machining, CNC machining, micromachining, or injection molding. Further, the material for manufacturing the disk is readily available, leading to an advantage of low manufacturing cost.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The present invention will be apparent to those skilled in the art by reading the following description of preferred embodiments thereof, with reference to the attached drawings, in which:
[0015] FIG. 1 is a perspective view showing a disk-based fluid sample separation device constructed in accordance with a first embodiment of the present invention;
[0016] FIG. 2 is an exploded view showing the disk-based fluid sample separation device of first embodiment of the present invention;
[0017] FIG. 3 is a top plan view showing a microfluidic disk of the first embodiment of the present invention;
[0018] FIG. 4 is a top plan view showing a sealing cover of the first embodiment of the present invention;
[0019] FIG. 5 is a schematic view showing an air passage of the sealing cover of the present invention in alignment with an air vent of a sample storage reservoir to set the air vent in an open condition;
[0020] FIG. 6 is a cross-sectional view showing the sealing cover of FIG. 5 in a first position;
[0021] FIG. 7 is a schematic view showing the sealing cover of the present invention being rotated by an angle to have the air passage aligning an air vent of another sample storage reservoir to set the air vent in an open condition;
[0022] FIG. 8 is a cross-sectional view showing the sealing cover of FIG. 7 in a second position;
[0023] FIG. 9 is a schematic view showing the air vent of the sample storage reservoir of the present invention in a closed condition, whereby a fluid sample contained in the sample storage reservoir is not allowed to flow to a sample processing reservoir;
[0024] FIG. 10 is a schematic view showing the air vent of the sample storage reservoir of the present invention in an open condition, whereby a fluid sample contained in the sample storage reservoir is acted upon by a centrifugal force to flow through a communication channel to the sample processing reservoir;
[0025] FIG. 11 is a cross-sectional view taken along line 11 - 11 of FIG. 1 ;
[0026] FIG. 12-16 are schematic views demonstrating a fluid sample contained in the sample storage reservoir according to the present invention and secondary samples contained in secondary sample storage reservoirs conducted, under the control of air vents and subjected to rotating motion, to the sample processing reservoir;
[0027] FIG. 17 is an exploded view showing a disk-based fluid sample separation device constructed in accordance with a second embodiment of the present invention;
[0028] FIG. 18 is a top plan view showing a disk-based fluid sample separation device constructed in accordance with a third embodiment of the present invention;
[0029] FIG. 19 is a cross-sectional view taken along line 19 - 19 of FIG. 18 ;
[0030] FIG. 20 is a cross-sectional view of an air passage opening/closing control unit of FIG. 19 setting an air vent in an open condition;
[0031] FIG. 21 is a cross-sectional view of the air passage opening/closing control unit of FIG. 19 setting an air vent in a closed condition;
[0032] FIG. 22 is a top plan view showing a disk-based fluid sample separation device constructed in accordance with a fourth embodiment of the present invention; and
[0033] FIG. 23 is a cross-sectional view taken along line 23 - 23 of FIG. 22 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0034] With reference to the drawings and in particular to FIG. 1 , which is a perspective view showing a disk-based fluid sample separation device constructed in accordance with a first embodiment of the present invention, and FIG. 2 , which is an exploded view showing the disk-based fluid sample separation device of first embodiment of the present invention, the disk-based fluid sample separation device according to the present invention, generally designated at 100 , comprises a microfluidic disk 1 , which has a geometric center 11 , a top surface 12 , and a circumferential surface 13 , and is coupled, at the geometric center 11 , to a spindle of a rotation driving device 14 , whereby the microfluidic disk 1 is selectively driven by the rotation driving device 14 to rotate about the geometric center 11 , which serves as a rotation center, in a predetermined rotation direction I.
[0035] The microfluidic disk 1 forms a flow channel pattern 2 . In the instant embodiment, the microfluidic disk 1 is composed of a bottom base board 15 and a flow channel pattern layer 16 formed on the bottom base board 15 . The flow channel pattern 2 is defined in and by the flow channel pattern layer 16 . The microfluidic disk 1 is covered by a sealing cover 3 set on the top surface 12 thereof.
[0036] Referring also to FIG. 3 , which is a top plan view of the microfluidic disk 1 shown in FIG. 2 , the flow channel pattern 2 comprises at least one sample storage reservoir 21 , which is formed in the flow channel pattern layer 16 of the microfluidic disk 1 to store a fluid sample (such as a blood sample). The sample storage reservoir 21 is in fluid communication with at least one air vent 211 . The flow channel pattern 2 also comprises at least one secondary sample storage reservoir 21 a , which is formed in the flow channel pattern layer 16 of the microfluidic disk 1 for store a secondary sample (such as reaction reagent). Each of the secondary sample storage reservoirs 21 a is set in fluid communication with a respective air vent 211 a.
[0037] A plurality of secondary sample storage reservoirs 21 a that comprises air vents 211 a may be arranged on the microfluidic disk 1 as a circle centered at the geometric center 11 . Alternatively, secondary sample storage reservoirs comprising air vents may be arranged along inner and outer concentric circles on the microfluidic disk 1 . In the embodiment illustrated, a plurality of secondary sample storage reservoirs 21 a that each comprises an air vent 211 a is arranged as an outer circle in the flow channel pattern layer 16 of the microfluidic disk 1 , and a plurality of secondary sample storage reservoirs 21 b that each comprises an air vent 211 b is arranged as an inner, concentric circle in the flow channel pattern layer 16 of the microfluidic disk 1 .
[0038] The flow channel pattern 2 further comprises at least one sample processing reservoir 22 . The sample processing reservoir 22 is located closer to the circumferential surface 13 of the microfluidic disk 1 than the sample storage reservoir 21 is. The sample processing reservoir 22 has a fluid inlet end 221 and a fluid outlet end 222 . The fluid inlet end 221 communicates through at least one communication channel 23 , 23 a with the sample storage reservoir 21 and the secondary sample storage reservoirs 21 a . The fluid outlet end 222 communicates with a capillary 24 . The capillary 24 has an opposite end extending to the circumferential surface 13 of the microfluidic disk 1 to form an opening 241 .
[0039] In the instant embodiment, the bottom base board 15 and the flow channel pattern layer 16 are both made of acrylic resins, such as polymethylmethacrylate (PMMA), and the sealing cover 3 is made of a transparent material. Laser light, such as CO2 laser, is employed to machine the flow channel pattern layer 16 for forming the flow channel pattern 2 . The flow channel pattern layer 16 so formed may then be combined with the bottom base board 15 . Afterwards, the sealing cover 3 is set to cover the flow channel pattern layer 16 to thereby seal the top of the flow channel pattern 2 .
[0040] Apparently, the flow channel pattern layer 16 can alternatively be formed as a multiple-layered structure by stacking or laminating multiple layers. Further, the microfluidic disk 1 can be alternatively made a single-layered structure and the material used is not limited to acrylic resins. The flow channel pattern 2 can alternatively be machined by for example other types of laser machining, or CNC machining, micromachining, and injection molding.
[0041] The sealing cover 3 is positioned on the top surface of the microfluidic disk 1 and forms at least one air passage 31 a , 31 b (also see FIGS. 2 and 4 ). The sealing cover 3 is rotatable with respect to the microfluidic disk 1 . For example, when the sealing cover 3 is rotated to a first angular position P 1 (also see FIG. 5 , as well as the cross-sectional view of FIG. 6 ), the air passage 31 a of the sealing cover 3 is located exactly corresponding to the air vent 211 a of the sample storage reservoir 21 a , thereby setting the air vent 211 a in an open condition, while the air vents of the remaining sample storage reservoir are kept in a closed condition. Under this condition, the microfluidic disk 1 is driven to rotate about the geometric center 11 , and the air passage (such as 31 a ) of the sealing cover 3 is in alignment with the air vent (such as 211 a ) of a selected sample storage reservoir (such as 21 a ), the fluid sample stored in the selected sample storage reservoir 21 a may be driven by a centrifugal force to flow through the communication channel 23 a into the sample processing reservoir 22 .
[0042] When the sealing cover 3 is rotated by a predetermined angle θ (also see FIG. 7 , as well as the cross-sectional view of FIG. 8 ), the air passage 31 b of the sealing cover 3 is positioned to align the air vent 211 b of the sample storage reservoir 21 b , thereby setting the air vent 211 b in an open condition, while the air vents of the remaining sample storage reservoirs are kept closed. The number of the air passages formed in the sealing cover 3 may be varied as desired, and the locations where the air passages are formed are also variable as desired. Through the selective rotation of the sealing cover 3 , it is possible to selectively set the air vent of each individual sample storage reservoir in an open condition or a closed condition.
[0043] Taking the sample storage reservoir 21 as an example, when the air vent 211 of the sample storage reservoir 21 is set in a closed condition (see FIG. 9 ), the fluid sample W contained in the sample storage reservoir 21 is not allowed to flow to the sample processing reservoir 22 , whether the microfluidic disk 1 is kept standstill (not in rotation) or the microfluidic disk 1 is in rotation. On the other hand, when the air vent 211 of the sample storage reservoir 21 in an open condition (see FIG. 10 ), if the microfluidic disk 1 is kept in standstill (not in rotation), the fluid sample W contained the sample storage reservoir 21 cannot flow to the sample processing reservoir 22 , but if the microfluidic disk 1 is driven and rotated, the fluid sample W contained in the sample storage reservoir 21 is acted upon by centrifugal force to flow into the sample processing reservoir 22 .
[0044] With such an operation model, for an arrangement of a plurality of sample storage reservoirs, the angular displacement θ of the sealing cover 3 can be selected through rotation of the cover (see FIG. 7 ) in order to selectively set the air vents of some of the sample storage reservoirs in a closed condition, while the air vents of the selected sample storage reservoirs are simultaneously opened to allow the fluid samples contained in the selected sample storage reservoirs to flow into the sample processing reservoir. Repeating the rotating and positioning process for the sealing cover 3 would allow the fluid sample contained in each of the sample storage reservoirs to be conducted into the sample processing reservoir (see FIG. 10 ).
[0045] Compared to a hydrophobic valve or a capillary valve adopted in the conventional centrifugal microfluidic platforms, the device of the present invention is less prone to influence by the nature of fluid sample, surface characteristics, size of communication channel, and rotational speed of microfluidic disk.
[0046] Also referring to FIG. 11 , which is a cross-sectional view taken along line 11 - 11 of FIG. 1 , at least one magnetic unit 4 is additionally provided on the top of the sealing cover 3 at a location corresponding to the sample processing reservoir 22 of the microfluidic disk 1 for providing a predetermined magnetic field above the sample processing reservoir 22 of the microfluidic disk 1 .
[0047] In an example application, the present invention is applied to separation of cells that are labeled with immunomagnetic beads. A fluid sample W with which the operation of cell separation is to be performed is first filled into the sample storage reservoir 21 . The fluid sample W contains two types of cell, one of which (target samples W 1 ) is labeled with immunomagnetic beads C. With the sealing cover 3 being angularly displaced to have the air passage 31 a aligning the air vent 211 of the sample storage reservoir 21 and thus opening the air vent 211 , when the microfluidic disk 1 is driven by the rotation driving device 14 to rotate in a predetermined rotation direction I, the fluid sample W is acted upon by the centrifugal force induced by the rotation of the microfluidic disk 1 and thus flows from the sample storage reservoir 21 through the communication channel 23 into the sample processing reservoir 22 . Under this condition, the target samples W 1 that are labeled with immunomagnetic beads C contained in the fluid sample W are subjected to magnetic attraction induced by the magnetic unit 4 to collect at the underside of the sealing cover 3 . In the embodiment illustrated, the magnetic unit 3 comprises a rectangular array of magnets, which applies a uniform magnetic field of a predetermined intensity on the sample processing reservoir 22 of the microfluidic disk 1 .
[0048] In another example of application, the present invention is used to separate for example MCF7 cells and Jurkat cells. It is apparent that the present invention is applicable to separation of fetal cells, separation of cells from whole blood sample, and separation of endothelial colony forming cells (ECFC) contained in umbilical cord blood (UCB).
[0049] FIGS. 12-16 are schematic views demonstrating a fluid sample contained in the sample storage reservoir according to the present invention and secondary samples contained in secondary sample storage reservoirs conducted, under the control of air vents and subjected to rotating motion, to the sample processing reservoir. Firstly, the fluid sample is filled into the sample storage reservoir 21 and secondary samples are respectively filled into the respective secondary sample storage reservoirs 21 a , 21 b (see FIG. 12 ). The sealing cover 3 is then rotated to have the air passage 31 b of the sealing cover 3 aligning the air vent 211 a of the sample storage reservoir 21 a . Afterwards, when the microfluidic disk 1 is put into rotation, the secondary sample contained in the secondary sample storage reservoir 21 a is acted upon by a centrifugal force to flow through the communication channel 23 a into the sample processing reservoir 22 (see FIG. 13 ).
[0050] After the secondary sample of the secondary sample storage reservoir 21 a is completely received into the sample processing reservoir 22 (see FIG. 14 ), the sealing cover 3 may be rotated again to have the air passage 31 a of the sealing cover 3 aligning the air vent 211 b of the sample storage reservoir 21 b (see FIG. 15 ). Under this condition, when the microfluidic disk 1 is put into rotation, the secondary sample contained in the secondary sample storage reservoir 21 b is acted upon by a centrifugal force to flow through the communication channel 23 b into the sample processing reservoir 22 (see FIG. 16 ). As such, through sequential rotation of the sealing cover 3 , the fluid sample contained in the sample storage reservoir 22 and the secondary samples contained in the secondary sample storage reservoirs 21 a , 21 b can be individually conducted into the sample processing reservoir 22 .
[0051] FIG. 17 is an exploded view showing a disk-based fluid sample separation device constructed in accordance with a second embodiment of the present invention, wherein the disk-based fluid sample separation device 100 a of the second embodiment is formed of multiple layers stacked together, comprising a sealing cover 3 , three flow channel pattern layers 16 a , 16 b , 16 c , and a bottom base board 15 .
[0052] In the previously discussed embodiments, the sealing cover 3 is positioned on the microfluidic disk 1 and is manually operable for rotation so as to have the air passage of the sealing cover 3 to correspond to or close an air vent of a selected sample storage reservoir. In another embodiment of the present invention, manual rotation of the sealing cover 3 is substituted by motor-driven rotation. Further, the air vent of the sealing cover 3 may be replaced by a solenoid controlled air vent structure.
[0053] For example, FIG. 18 is a top plan view showing a disk-based fluid sample separation device constructed in accordance with a third embodiment of the present invention, and FIG. 19 is a cross-sectional view taken along line 19 - 19 of FIG. 18 . In this embodiment, the disk-based fluid sample separation device, which is designated at 100 b , similarly comprises a microfluidic disk 5 that forms a flow channel pattern composed of a plurality of sample storage reservoirs 51 and/or secondary sample storage reservoir(s). A sealing cover 6 is set to cover the microfluidic disk 5 . The sealing cover 6 forms air vent channels 61 corresponding to the sample storage reservoirs 51 of the microfluidic disk 5 . Each air vent channel 61 has a top end to which an air passage opening/closing control unit 7 (such as a solenoid) is mounted and each air vent channel 61 has a bottom end 61 a corresponding to and in fluid communication with the respective sample storage reservoir 51 . The top end of each the air vent channel 61 forms an air passage 61 b.
[0054] Referring to FIGS. 20 and 21 , which are cross-sectional views of the air passage opening/closing control unit 7 respectively showing the air vent in open and closed conditions as being controlled by the air passage opening/closing control unit, the air passage opening/closing control unit 7 comprises a solenoid 71 , an electromagnetic operation unit 72 , and a valve membrane 73 . When the solenoid 71 is excited by electrical power applied thereto, the electromagnetic operation unit 72 is operated to move the valve membrane 73 upwards, making the air vent channel 61 communicating an external air channel 61 c (see FIG. 20 ), whereby the fluid sample contained in the sample storage reservoir 51 , when acted upon by a centrifugal force, is allowed to flow out through the communication channel 51 a . When the solenoid 71 does not receive electrical power applied thereto, the electromagnetic operation unit 72 is not operated and the valve disk 73 returns to the original position to block the air vent channel 61 from the external air channel 61 c (see FIG. 21 ). Under this condition, the fluid sample stored in the sample storage reservoir 51 is prohibited from flowing out.
[0055] FIG. 22 is a top plan view showing a disk-based fluid sample separation device 100 c constructed in accordance with a fourth embodiment of the present invention, and FIG. 23 is a cross-sectional view taken along line 23 - 23 of FIG. 22 . In this embodiment, an arrangement that a single air passage opening/closing control unit 7 is operable for controlling multiple sample storage reservoirs 51 is provided. In other words, the sealing cover 6 has an air vent channel 61 that has a bottom end 61 a , which besides being in fluid communication with a sample storage reservoir 51 , is in communication with an extended air vent channel 2 for further communicating other sample storage reservoirs 51 through the extended air vent channel 62 , whereby when the solenoid 71 of the air passage opening/closing control unit 7 is excited by electrical power applied thereto, the fluid samples contained in the sample storage reservoirs 51 that are in communication with both the air vent channel 61 and the extended air vent channel 62 are allowed to flow out through the communication channel 51 a . When the solenoid 71 is not excited, the fluid sample contained in each of these sample storage reservoirs 51 is prohibited from flowing out.
[0056] Although the present invention has been described with reference to the preferred embodiments thereof, it is apparent to those skilled in the art that a variety of modifications and changes may be made without departing from the scope of the present invention which is intended to be defined by the appended claims. | A disk-based fluid sample separation device including at least one air vent forming a part of a flow channel pattern on a microfluidic disk is disclosed. The fluid sample separation device is provided with an air vent sealing cover having at least through hole and is placed on the top surface of the disk. The air vent sealing cover is rotated with respect to the disk either at a first position or a second position. At the first position, the hole of the air vent sealing cover is in correspondence to the air vent of the flow channel pattern to control the sample liquid delivery. At the second position, the air vent of the flow channel pattern is closed. The flow channel pattern includes at least one sample storage reservoir, at least one sample processing reservoir, and at least one communication channel which is in fluid communication between the sample storage reservoir and the sample processing reservoir. In alternative, the status of the hole of the air vent sealing cover is controlled by a control unit. | 1 |
TECHNICAL FIELD
[0001] This description relates to electrosurgical generators.
BACKGROUND
[0002] Lower back pain is a common ailment and affects many people at some point in their lives. Frequently, this pain is the result of cracks or fissures that develop in the wall of the intervertebral disc. These fissures are filled with small nerve endings and blood vessels, and often are a chronic source of pain. Additionally, the inner disc tissue (nucleus) frequently bulges (herniates) into these fissures in the outer region of the disc, likewise stimulating pain sensors within the disc.
[0003] Electrosurgical procedures provide minimally invasive treatment options for treating lower back pain by applying thermal energy (i.e., heat) to the affected area. Electrosurgical procedures have been developed for use in other pain management procedures, such as denervation procedures. An electrosurgical generator provides electrical energy, such as, for example, high frequency and radio frequency electrical energy. In particular, the electrical energy provided by the electrosurgical generator is used in pain management procedures to modify the structure of tissue.
SUMMARY
[0004] The electrosurgical generator can be used, for example, to provide radio-frequency (RF) energy for localized tissue coagulation, cutting, ablation, and to create lesions in nervous tissue. The generator is, e.g., a line-powered radio-frequency generator capable of delivering up to approximately 20 watts of power. The generator can provide controls for line power, RF power, setting temperature and/or power, for selecting preset temperature and power combinations, and for selecting programmed treatment profiles. The generator can have a display to display the desired probe and tissue temperature, measured probe impedance, actual probe and/or tissue temperature, delivered power, treatment time, mode setting, preset selection, and messages, and indicators for RF Power On, Stimulation On, and Fault Condition. The software for the generator can be upgraded using a special card.
[0005] The generator can include the ability to generate low frequency pulses to stimulate nerves and to assist in the proper placement of the electrosurgical probe in the location that is causing pain. For example, the generator may include the ability to generate low frequency pulses of 0.1 to 3 ms in duration at a frequency between approximately 2-50 hz.
[0006] Temperature and impedance monitoring can be used to assist the surgeon by automatically adjusting energy delivery to maintain effective tissue heating during temperature control applications. Preset temperature and power settings can offer the convenience of quickly configuring the generator for use. Programmed temperature profiles can provide the convenience of selecting a treatment setting for use with a particular type of probe, for example, the Smith and Nephew SPINECATH® Intradiscal Catheter, the Smith and Nephew Decompression Catheter, and the Smith & Nephew RF Denervation Probe.
[0007] In one general aspect, a method includes recognizing an electrosurgical probe coupled to an electrosurgical generator, selecting a mode of the electrosurgical generator based upon the recognized probe, setting a therapy profile based upon the selected mode, and displaying the therapy profile. The generator can include user inputs for modifying the therapy profile.
[0008] Implementations may include one or more of the following features:
[0009] Setting the therapy profile includes automatically setting a default parameters for the selected mode. The therapy profile includes an automatic temperature profile, such as a temperature rise from an initial temperature to a peak temperature and a dwell time at the peak temperature. The temperature rise is, e.g., a fixed rate of temperature rise such as one degree Celsius per thirty seconds, one degree Celsius per six seconds, or one degree Celsius per eighteen seconds. Alternatively, the temperature rise is discontinuous. The rate of temperature rise is selected automatically. The initial temperature, the peak temperature and/or the dwell time at the peak temperature is selected automatically and also can be manually overridden.
[0010] In one implementation, the therapy profile includes a frequency parameter and a pulsewidth parameter. The therapy profile also can include an adjustable voltage parameter. A rotary encoder knob that is configured to adjust the voltage parameter can be used.
[0011] In another implementation, the therapy profile is switched between a first therapy profile and a second therapy profile. A user modified parameter may be retained when switching between the first therapy profile and the second therapy profile. The therapy profile includes a temperature parameter and a time duration parameter, and also can include a frequency parameter, a pulsewidth parameter, and/or an amplitude parameter. The frequency parameter, the pulsewidth parameter, and/or the amplitude parameter can be adjusted to control a tissue temperature. The pulsewidth may be, for example, 20 ms. In one implementation, the frequency parameter and/or the amplitude parameter are adjusted to control tissue temperature and the pulse width parameter is not adjustable.
[0012] The display of at least a portion of the display of the therapy profile can be updated. The therapy profile can be modified, and the modified therapy profile can be displayed.
[0013] In another general aspect, a computer program stored on a computer readable medium includes instructions for recognizing an electrosurgical probe coupled to an electrosurgical generator, selecting a mode of the electrosurgical generator based upon the recognized probe, setting a therapy profile based upon the selected mode, and displaying the therapy profile. The generator can include user inputs for modifying the therapy profile.
[0014] In another general aspect, a computer implemented method for achieving a target temperature includes: a) receiving the target temperature; b) calculating a first set temperature; c) commanding a first output power level until a measured temperature is equal to or greater than the first set temperature; d) calculating an updated set temperature based upon the target temperature; e) commanding a second output power level until the measured temperature is equal to or greater than the updated set temperature; and repeating d and e until the updated set temperature is equal to the target temperature.
[0015] Implementations may include one or more of the following features:
[0016] Receiving the target temperature can include retrieving the target temperature from a storage location and receiving the target temperature can include receiving a user input. Calculating the first set temperature can include subtracting a predetermined value from the target temperature or retrieving a pre-stored value. The first power output level can be a maximum power output level, and the second power output level can be a power output level less than the maximum power output level. The maximum power output level can be a maximum output power level for a particular probe being used. In another implementation, the maximum output power level can be the maximum power output level of the generator. In other implementations, the maximum output power level can be a different pre-determined value or a dynamically calculated value. The first output power level can be an output power level based upon an identity of a surgical probe. The first power output level can be greater than the second power output level. Calculating the updated set temperature can include subtracting a predetermined value from the target temperature, adding a predetermined value to the first set temperature, or retrieving a pre-stored value.
[0017] In another implementation, a proportional-integral routine can be used to control to the target temperature by adjusting the output voltage.
[0018] In another general aspect, a computer program stored on a computer readable medium includes instructions for: a) receiving a target temperature; b) calculating a first set temperature; c) commanding a first output power level until a measured temperature is equal to or greater than the first set temperature; d) calculating an updated set temperature based upon the target temperature; e) commanding a second output power level until the measured temperature is equal to or greater than the updated set temperature; and repeating d and e until the updated set temperature is equal to the target temperature.
[0019] In another general aspect, an electrosurgical generator includes means for recognizing an electrosurgical probe, means for selecting a mode of the electrosurgical generator based upon the recognized probe and for setting a therapy profile based upon the selected mode, means for displaying the therapy profile, and means for modifying the therapy profile.
[0020] Implementations can include one or more of the following features:
[0021] The means for recognizing the electrosurgical probe can include a probe recognition circuit. The means for selecting the mode and for setting the therapy profile can include a processor. The means for displaying the therapy profile can include a visual display, such as, for example, an LCD display. The means for modifying the therapy profile can include a user control, such as, for example, a soft key, an arrow key, or a rotary encoder knob.
[0022] In another general aspect, an electrosurgical generator includes a probe recognizing circuit configured to recognize an electrosurgical probe, a processor configured to select a mode of the electrosurgical generator based upon the recognized probe and to set a therapy profile based upon the selected mode, a display configured to display the therapy profile, and a user control configured to modify the therapy profile.
[0023] Implementations can include one or more of the following features:
[0024] The display can include a visual display, such as, for example, an LCD display. The user control may include, for example, a soft key, an arrow key, or a rotary encoder knob.
[0025] In another general aspect, an electrosurgical generator includes means for receiving a target temperature, calculating a first set temperature, commanding a first output power level until a measured temperature is equal to or greater than the first set temperature, calculating an updated set temperature based upon the target temperature, commanding a second output power level until the measured temperature is equal to or greater than the updated set temperature, and determining whether the updated set temperature is equal to the target temperature, and means for modifying the target temperature.
[0026] Implementations can include one or more of the following features:
[0027] The means for receiving the target temperature, calculating a first set temperature, commanding a first output power level until a measured temperature is equal to or greater than the first set temperature, calculating an updated set temperature based upon the target temperature, commanding a second output power level until the measured temperature is equal to or greater than the updated set temperature, and determining whether the updated set temperature is equal to the target temperature can include a processor. In one implementation, the processor is configured to retrieve the target temperature from a storage location. In another implementation, the processor is configured to receive the target temperature from a user input.
[0028] In one implementation, the processor is configured to subtract a predetermined value from the target temperature to obtain the first set temperature. In another implementation, the processor is configured to retrieve a pre-stored value of the first set temperature. In one implementation, the processor is configured to subtract a predetermined value from the target temperature to obtain the updated set temperature. In another implementation, the processor is configured to add a predetermined value to the first set temperature to obtain the updated set temperature. In yet another implementation, the processor is configured to retrieve a pre-stored value of the updated set temperature. The first power output level can be greater than the second power output level, and the means for modifying the target temperature can include a user control.
[0029] In another implementation, the set temperature is not ramped to the target temperature. Instead, the measured temperature is controlled directly to achieve the target temperature. The set temperature is not changed or updated. A proportional-integral routine, or other similar routine, can be used to control to the target temperature by adjusting the output voltage.
[0030] In another implementation, a first output power can be commanded if the measured temperature is less than a specified value below the target temperature. Once the measured temperature is within the specified value of the target temperature, a control routine, such as a PID or a PI routine, can be used to calculate a second output level for the generator.
[0031] In another general aspect, an electrosurgical generator includes a processor configured to receive the target temperature, calculate a first set temperature, command a first output power level until a measured temperature is equal to or greater than the first set temperature, calculate an updated set temperature based upon the target temperature, command a second output power level until the measured temperature is equal to or greater than the updated set temperature, and determine whether the updated set temperature is equal to the target temperature.
[0032] Implementations can include one or more of the following features:
[0033] The processor can be configured to retrieve the target temperature from a storage location or receive the target temperature from a user input. The processor can configured to calculate the first set temperature by subtracting a predetermined value from the target temperature or by retrieving a pre-stored value. The processor can be configured to calculate the updated set temperature by subtracting a predetermined value from the target temperature, by adding a predetermined value to the first set temperature, or by retrieving a pre-stored value.
[0034] The first power output level can be greater than the second power output level. The generator can include a user control configured to modify the target temperature.
[0035] In another general aspect, a computer program stored on a computer readable medium includes instructions for: a) receiving a target temperature; b) commanding a first output power level until a measured temperature is within a specified value of the target temperature; c) calculating a second output power level when the measured temperature is within the specified value of the target temperature; d) commanding the second output power level; and repeating c and d until the measured temperature is equal to the target temperature.
[0036] Implementations can include one or more of the following features:
[0037] The instructions for receiving the target temperature can include instructions for receiving a user input. The first output power level can include a maximum output power level. The maximum output power level can include a maximum output power level based upon an identity of a surgical probe. The second output power level can include a output power level less than the maximum output power level. The first output power level can be an output power level based upon an identity of a surgical probe. The first output power level can be greater than the second output power level. The instructions for calculating the second output power level can include instructions for using a PID algorithm or a PI algorithm to calculate the second output power level. The instructions can also include instructions for receiving an initial second output power level. The instructions for receiving an initial second output power level can include instructions for retrieving the initial second output power level from a storage location. The initial second output power level can be based upon an identity of a surgical probe. The instructions for calculating the second output power level c can include instructions for retrieving a pre-stored value.
[0038] In another general aspect, a method for achieving a target temperature includes: a) receiving a target temperature; b) commanding a first output power level until a measured temperature is within a specified value of the target temperature; c) calculating a second output power level when the measured temperature is within the specified value of the target temperature; d) commanding the second output power level; and repeating c and d until the measured temperature is equal to the target temperature.
[0039] In another general aspect, an electrosurgical generator can include means for receiving a target temperature, commanding a first output power level until a measured temperature is within a specified value of the target temperature, calculating a second output power level when the measured temperature is within the specified value of the target temperature, commanding the second output power level, and determining whether the measured temperature is equal to the target temperature and means for modifying the target temperature.
[0040] Implementations can include one or more of the following features:
[0041] The means for receiving a target temperature, commanding a first output power level until a measured temperature is within a specified value of the target temperature, calculating a second output power level when the measured temperature is within the specified value of the target temperature, commanding the second output power level, and determining whether the measured temperature is equal to the target temperature can include a processor.
[0042] In another general aspect, an electrosurgical generator can include a processor configured to receive a target temperature, command a first output power level until a measured temperature is within a specified value of the target temperature, calculate a second output power level when the measured temperature is within the specified value of the target temperature, command the second output power level, and determine whether the measured temperature is equal to the target temperature.
[0043] Implementations can include one or more of the following features:
[0044] The processor can be configured to retrieve the target temperature from a storage location. The processor can be configured to receive the target temperature from a user input. The first output power level can include an output power level based upon an identity of a surgical probe. The first output power level can be greater than the second output power level. The electrosurgical generator can include a user control configured to modify the target temperature.
[0045] In another general aspect, a computer program stored on a computer readable medium includes instructions for: a) receiving a target temperature; b) receiving a first generator output setting corresponding to a first generator output power; c) commanding the first generator output setting when a difference between the target temperature and a measured temperature is greater than a specified value; d) calculating a second generator output setting if the first generator output power is less than a maximum allowed generator output power for an identified surgical probe and if the difference between the target temperature and the measured temperature is greater than the specified value, wherein the second generator output setting corresponds to a second generator output power that is greater than the first generator output power, and commanding the second generator output setting; e) calculating a third generator output setting if the first generator output power is greater than the maximum allowed generator output power for the identified surgical probe and the difference between the target temperature and the measured temperature is greater than the specified value, wherein the third generator output setting corresponds to a third generator output power that is less than the first generator output power, and commanding the third generator output setting; and f) repeating c through e until the difference between the target temperature and the measured temperature is less than or equal to the specified value.
[0046] Implementations can include one or more of the following features:
[0047] The instructions for receiving the target temperature can include instructions for receiving a user input. The instructions for calculating the second generator output setting can include instructions for adding a predetermined value to the first generator output setting. The instructions for calculating the third generator output setting can include instructions for subtracting a predetermined value from the first generator output setting.
[0048] The computer program can further include instructions for: g) calculating a fourth generator output setting corresponding to a fourth generator output power if the difference between the target temperature and the measured temperature is less than or equal to the specified value; and h) commanding the fourth generator output setting. Instructions for calculating the fourth generator output setting can include instructions for calculating the fourth generator output setting using a control algorithm. The control algorithm can include setting the fourth generator output setting equal to a first constant multiplied by an integral of an error value plus a second constant multiplied by the error value, wherein the first constant and the second constant are defined for an identified surgical probe and the error value equals the target temperature minus the measured temperature.
[0049] The computer program can further include instructions for limiting the fourth generator output control setting to a maximum value. The maximum value can include the first generator output control setting. The computer program can include instructions for not integrating the error value when the fourth generator control setting is equal to the maximum value. The computer program can include instructions for limiting the fourth generator output control setting to a minimum value. The minimum value can be zero.
[0050] In another general aspect, a method for achieving a target temperature includes: a) receiving a target temperature; b) receiving a first generator output setting corresponding to a first generator output power; c) commanding the first generator output setting when a difference between the target temperature and a measured temperature is greater than a specified value; d) calculating a second generator output setting if the first generator output power is less than a maximum allowed generator output power for an identified surgical probe and if the difference between the target temperature and the measured temperature is greater than the specified value, wherein the second generator output setting corresponds to a second generator output power that is greater than the first generator output power, and commanding the second generator output setting; e) calculating a third generator output setting if the first generator output power is greater than the maximum allowed generator output power for the identified surgical probe and the difference between the target temperature and the measured temperature is greater than the specified value, wherein the third generator output setting corresponds to a third generator output power that is less than the first generator output power, and commanding the third generator output setting; and f) repeating c through e until the difference between the target temperature and the measured temperature is less than or equal to the specified value.
[0051] In another general aspect, an electrosurgical generator includes: means for receiving a target temperature, receiving a first generator output setting corresponding to a first generator output power, commanding the first generator output setting when a difference between the target temperature and a measured temperature is greater than a specified value, calculating a second generator output setting if the first generator output power is less than a maximum allowed generator output power for an identified surgical probe and if the difference between the target temperature and the measured temperature is greater than the specified value, wherein the second generator output setting corresponds to a second generator output power that is greater than the first generator output power, and commanding the second generator output setting, calculating a third generator output setting if the first generator output power is greater than the maximum allowed generator output power for the identified surgical probe and the difference between the target temperature and the measured temperature is greater than the specified value, wherein the third generator output setting corresponds to a third generator output power that is less than the first generator output power, and commanding the third generator output setting and determining whether the difference between the target temperature and the measured temperature is less than or equal to the specified value; and means for modifying the target temperature.
[0052] In another general aspect, an electrosurgical generator includes a processor configured to: receive a target temperature; receive a first generator output setting corresponding to a first generator output power; command the first generator output setting when a difference between the target temperature and a measured temperature is greater than a specified value; calculate a second generator output setting if the first generator output power is less than a maximum allowed generator output power for an identified surgical probe and if the difference between the target temperature and the measured temperature is greater than the specified value, wherein the second generator output setting corresponds to a second generator output power that is greater than the first generator output power, and command the second generator output setting; calculate a third generator output setting if the first generator output power is greater than the maximum allowed generator output power for the identified surgical probe and the difference between the target temperature and the measured temperature is greater than the specified value, wherein the third generator output setting corresponds to a third generator output power that is less than the first generator output power, and command the third generator output setting; and determine whether the difference between the target temperature and the measured temperature is less than or equal to the specified value.
[0053] Implementations can include one or more of the following:
[0054] The processor can be configured to retrieve the target temperature from a storage location. The processor can be configured to receive the target temperature from a user input.
[0055] Other features will be apparent from the description and drawings, and from the claims.
DESCRIPTION OF DRAWINGS
[0056] FIG. 1 is a perspective view of an electrosurgical generator.
[0057] FIG. 2 is a plan view of a front panel of the electrosurgical generator of FIG. 1 .
[0058] FIG. 3 is an exemplary standby mode interface implemented by the electrosurgical generator of FIG. 1 while executing the processes of FIGS. 4, 11 , 12 , and 13 .
[0059] FIGS. 4, 11 , 12 , and 13 are flow charts of exemplary processes implemented by the electrosurgical generator of FIG. 1 .
[0060] FIG. 5 is an exemplary SPINECATH® AUTOTEMP®D mode interface implemented by the electrosurgical generator of FIG. 1 while executing the processes of FIGS. 4, 11 , 12 , and 13 .
[0061] FIG. 6 is an exemplary Decompression AUTOTEMP® mode interface implemented by the electrosurgical generator of FIG. 1 while executing the processes of FIGS. 4, 11 , 12 , and 13 .
[0062] FIG. 7 is an exemplary Sensory Stimulate mode interface implemented by the electrosurgical generator of FIG. 1 while executing the processes of FIGS. 4, 11 , 12 , and 13 .
[0063] FIG. 8 is an exemplary Motor Stimulate mode interface implemented by the electrosurgical generator of FIG. 1 while executing the processes of FIGS. 4, 11 , 12 , and 13 .
[0064] FIG. 9 is an exemplary RF Lesion mode interface implemented by the electrosurgical generator of FIG. 1 while executing the processes of FIGS. 4, 11 , 12 , and 13 .
[0065] FIG. 10 is an exemplary Pulsed RF mode interface implemented by the electrosurgical generator of FIG. 1 while executing the processes of FIGS. 4, 11 , 12 , and 13 .
DETAILED DESCRIPTION
[0066] As shown in FIG. 1 , an electrosurgical generator 100 includes a chassis 105 , and a front panel 110 . The front panel 110 includes a display 115 , soft keys 120 , arrow keys 125 , status indicators 130 , an RF output on/off control button 135 , a grounding pad receptacle 140 , a probe receptacle 145 , and a rotary encoder knob 150 . Probe receptacle 145 receives a probe 165 via a cable plug 160 , a cable 155 , and a cable plug 162 . The display 115 is, for example, an LCD screen that displays certain information during a surgical procedure, as will be discussed in more detail below with respect to FIGS. 2-3 and 5 - 10 .
[0067] Generator 100 can be used with probes such as, for example, the Smith and Nephew SPINECATH® Intradiscal Catheter, the Smith and Nephew Decompression Catheter, and the Smith & Nephew RF Denervation Probe. The electrosurgical generator 100 is capable of therapy profiles through several modes of operation, including SPINECATH® AUTOTEMP® (automatic temperature) mode, Decompression AUTOTEMP® mode, stimulation mode, RF lesion mode, and Pulsed RF mode. When using the Smith & Nephew RF Denervation Probe, the generator initially enters the stimulation mode, and the RF lesion mode or Pulse RF mode is accessed through the stimulation mode.
[0068] During a disc denervation procedure, the rotary encoder knob 150 is used to turn on/off the stimulation mode output voltage and adjust the stimulation mode output voltage for motor and sensory stimulus prior to applying RF energy to treat tissue. The rotary encoder knob is pushed to turn the stimulation mode power on or off. With the stimulation mode power on, the rotary encoder knob 150 can be rotated clockwise to increase the stimulation mode output voltage and counter clockwise to decrease the stimulation mode output voltage.
[0069] In all modes other than stimulation mode, the RF output on/off control button 135 is used to start or stop RF power delivery. The button 135 is pressed, or alternatively, a foot switch (not shown) is pressed, to start and stop RF power delivery. If the RF output on/off control button 135 is pressed in succession, then RF power delivery toggles on and off.
[0070] Referring to FIG. 2 , the status indicators 130 include an indication for “RF On” such as an LED 240 that is illuminated when the electrosurgical generator 100 is delivering RF power in all modes but the stimulation mode, a “Stimulation On” indication such as an LED 245 that is illuminated when the generator 100 is delivering stimulation power, and a fault indication such as an LED 250 that is illuminated when a fault condition is detected. The arrow keys 125 and soft keys 120 are used to control different parameters for different modes of operation of the generator 100 . The soft keys and arrow keys are associated with controls shown in the display 115 . The operator manipulates a control by operating the soft key or arrow key corresponding to the control. Typically, the function associated with the soft key can change as the display is changed, and the arrow keys are used to adjust a particular parameter up or down.
[0071] As shown, the soft keys 120 include three separate soft keys 205 , 215 , and 220 . Soft key 205 operates on control 260 and soft key 215 operates on control 265 . In the implementation shown in FIG. 2 , soft key 220 does not have a corresponding control shown in the display 115 . Arrow keys 125 include three sets of arrow keys 225 , 230 , and 235 . Arrow keys 225 include a down arrow key 225 a and an up arrow key 225 b . Arrow keys 230 include a down arrow key 230 a and an up arrow key 230 b . Arrow keys 235 include a down arrow key 235 a and an up arrow key 235 b . The arrow keys 225 , 230 , and 235 operates on controls 280 , 275 , and 270 of display 115 , respectively.
[0072] When line power is initially applied to the generator 100 , the generator performs a system self-test to determine if it is performing properly. After the self-test, the generator 100 enters a standby mode in which RF power cannot be delivered. In the standby mode, a user interface (UI), such as the UI 300 shown in FIG. 3 , is displayed to the user on display 115 . To exit standby mode, a start control 305 is displayed on the user interface 300 after a probe 165 is connected to the generator. The start control 305 is activated by depressing soft key 220 . When activated, the start control 305 causes the generator 100 to exit the standby mode and enter an appropriate operating mode as described below.
[0073] FIG. 4 shows an exemplary procedure 400 employed using the electrosurgical generator 100 discussed above with respect to FIGS. 1 and 2 . After the operator powers up the generator 100 and the generator 100 boots (step 402 ), the operator connects a probe 165 to the generator 100 (step 405 ) and depresses soft key 220 to activate the start control 305 . The generator 100 recognizes the probe (step 410 ) and selects a desired mode based on the recognized probe (step 415 ). For example, if the recognized probe is a SPINECATH®, SPINECATH® AUTOTEMP® mode is entered, if the recognized probe is a Decompression Catheter, Decompression AUTOTEMP® mode is entered, and if the recognized probe is a Denervation Probe, the stimulate mode is entered.
[0074] The generator includes a processor (not shown) running software that recognizes which type of probe 165 is being connected to the generator by reading a sensor in the handle of the probe 165 . The processor can be, for example, a microprocessor. The processor is capable of responding to and executing instructions in a defined manner. The software can include a program, a piece of code, an instruction, a device, or a combination of these for independently or collectively instructing the processor to interact and operate as described. The software can be embodied permanently or temporarily in various types of machines, components, physical or virtual equipment, storage media, or propagated signals capable of providing instructions to the processor. The processor typically has an associated memory (not shown), such as an internal or external memory, for storing data and programs. In one implementation, the processor can access programs externally stored in and/or performed by one or more device(s) external to the processor. The processor can include a single processor or multiple processors.
[0075] The generator also includes a probe recognition circuit (not shown) that is configured to recognize a probe that is connected to the generator. In one implementation, the probe recognition circuit can recognize a probe by recognizing a resistance value of the probe. Different probes may be have different resistance values or ranges of resistance values. In one implementation, the probe recognition circuit measures a voltage that corresponds to a resistance value. The probe recognition circuit can convert the measured analog voltage into a digital value. In one implementation, the probe recognition circuit includes a feature to identify the probe based upon the digital value. In another implementation, the probe recognition circuit supplies the digital value to the processor and the processor identifies the probe.
[0076] When the probe 165 is connected to the generator 100 , the generator 100 automatically switches to the appropriate mode, resets a timer, and sets default values for the selected mode (step 420 ). Switching to the appropriate mode can include selecting a maximum allowed power output based on the recognized probe. The maximum allowed power for the recognized probe typically is less than the maximum power output of the generator. In one implementation, the processor controls the switching of the mode, the resetting of the time, and the setting of default values for the selected mode based on the recognized probe. The display 115 is updated to reflect the mode entered and the default values set (step 425 ). In one implementation, the processor supplies the mode entered and the default values to the display. The operator can change the default settings from the preset values using the soft keys and/or arrow keys (step 430 ). In one implementation, the soft keys and/or arrow keys are connected to provide an input to the processor to change the default settings. The display is updated (step 435 ) to reflect the values set by the operator. In one implementation, the processor supplies the values set by the operator to the display. The operator then performs the desired surgical procedure (step 440 ). During the surgical procedure, the operator may change the mode, if allowed (step 445 ). For example, when in stimulation mode, the operator can change between a motor stimulation mode and a sensory stimulation mode, and can change from a stimulation mode to RF lesion mode or pulsed RF mode. If the mode is changed, then steps 420 - 440 are repeated as described above for the new mode.
[0077] SPINECATH® AUTOTEMP® Mode
[0078] Referring to FIG. 5 , when the recognized probe is a SPINECATH®, the generator enters SPINECATH® AUTOTEMP® mode and user interface (UI) 500 is presented to the operator on display 115 . User interface 500 indicates the generator mode as the SPINECATH® mode 505 . Several parameters for the SPINECATH® mode are displayed to the operator. For example, the measured probe impedance 510 , elapsed procedure time 515 , actual probe temperature 525 , set temperature 530 , and set temperature profile 535 are displayed.
[0079] The actual probe temperature 525 is measured by a temperature sensing device, such as a thermocouple in the probe. The set temperature 530 is a target temperature that the generator 100 attempts to achieve and hold. The set temperature 530 can be entered manually by the operator or adjusted automatically by the generator 100 . For example, the set temperature 530 can be changed manually using arrow keys 230 or can be adjusted automatically by the generator 100 while executing a set profile 535 . Typically, a manual entry of set temperature 530 overrides an automatic adjustment of set temperature 530 . The set profile 535 is a peak temperature that is to be achieved by the generator 100 for a predetermined duration of time. The generator 100 increases the temperature in a controlled manner until the peak temperature is achieved, and dwells at the peak temperature for a predetermined dwell time. Multiple profiles can be stored, and a particular profile selected manually by the operator or automatically by the generator. The set profile can be changed manually using arrow keys 235 , or set automatically by the generator using a default setting or based upon other criteria. The operator also has a control 520 to reset the timer and set temperature using soft key 205 . Typically, the reset control 520 may be activated only after a pause in the delivery of RF energy. When reset, the timer re-zeroes, the set temperature 530 returns to the default value, and the set profile 535 remains unchanged.
[0080] An exemplary set of profiles is shown below in Table 1. The profiles include information about a peak temperature, the time required to achieve the peak temperature, the dwell time at the peak temperature, and the total treatment time. By manipulating arrow keys 235 , the operator can change the set profile, and the profile set by the operator will perform according to the values shown in Table 1. In the SPINECATH® auto-temperature mode, the set profile 535 typically defaults to the profile “P90”, which corresponds to a peak temperature of 90° C. Other implementations are possible, and the values in Table I are meant to be exemplary.
[0081] The generator 100 automatically ramps up the actual probe temperature in a controlled manner up to the peak temperature shown in Table 1 for the set profile 535 , and then dwells for the given dwell time at the peak temperature according to the profile. The set temperature 530 is the temperature at which the controlled ramp up is started. The set temperature 530 is initialized to a default value and is incremented by the generator in a controlled manner until the set temperature equals the peak temperature. As the generator automatically increments the set temperature, the displayed value of set temperature 530 in display 115 also is incremented.
[0082] For example, the parameters may include a default temperature profile “P90,” a default value of the set temperature of 65° C., and a measured probe temperature below 65° C. In this case, the generator initially increases the temperature up to a value of 65° C. by, for example, applying full power until the set temperature of 65° C. is achieved. Full power can be a maximum allowed power for a given probe, or may be the maximum power that can be supplied by the generator. Once delivery of RF power has begun the elapsed procedure time clock 515 begins counting up. When a probe temperature of 65° C. is reached, the generator follows a ramped profile which is usually defined by a temperature increment per unit time, e.g., 1° C. every 30 seconds. The temperature ramp typically is discontinuous because the temperature increment (e.g., 1° C.) often is achieved more rapidly than the increment of unit time allotted until the temperature increment (e.g., more rapidly than 30 seconds). In other words, the generator affects the 1° C. temperature increase much more quickly than 30 seconds, and the remainder of the 30 second period before the next increase is spent at the newly achieved temperature. A ramped profile that increments the temperature 1 ° C. every 30 seconds takes 12.5 minutes to reach the peak temperature 90° C. Once the peak temperature of 90° C. is reached, that temperature is maintained for the dwell time of 4.0 minutes, as shown in Table 1. The entire profile takes 16.5 minutes of total treatment time—12.5 minutes to achieve the peak temperature and 4 minutes duration at the peak temperature. Energy delivery automatically stops upon completion of the profile. Once the procedure is complete, another procedure typically cannot be started without first removing the probe 165 and inserting a new probe. The energy delivery is started, and can be stopped if desired, by pressing the RF output on/off control 135 or the foot switch (not shown).
[0083] The profiles are chosen to balance patient comfort against overall treatment time, and typically are derived experimentally. If the probe temperature is raised rapidly, the overall treatment time is decreased. However, it may be more likely to cause patient discomfort.
[0084] Because the tolerance of individuals will vary, the temperature may be raised more rapidly or more slowly than the exemplary profiles described herein.
[0085] In another implementation, the maximum power allowed for the particular probe is applied until the measured temperature is equal to or within a specified value, such as, for example, 1° C., of the target temperature. When the difference between the target temperature and the measured temperature is equal to or less than the specified value, a control routine, such as a proportional-integral (“PI”) routine, proportional-integral-derivative (“PID”) routine, or other suitable routine, is used to control to the target temperature by adjusting the output voltage of the generator. However, when the difference between the target temperature and the measured temperature is greater than the specified value, no control routine is used. Instead, the maximum power allowed for the particular probe is applied while the difference between the target temperature and the measured temperature is greater than the specified value. Thus, the specified value acts as a transition point between a mode of applying the maximum power output allowed for the particular probe and a mode of controlling the temperature by using a control routine. The control routine can control, for example, the power output or the voltage output of the generator.
[0086] SpineCATH Autotemp Profiles
TABLE 1 Peak Total Treatment Selected Temperature Time to Peak Dwell Time Time Profile ° C. (min.) (min.) (min.) P80 80 7.5 6.0 13.5 P81 81 8.0 5.7 13.7 P82 82 8.5 5.5 14.0 P83 83 9.0 5.5 14.5 P84 84 9.5 5.2 14.7 P85 85 10.0 5.0 15.0 P86 86 10.5 4.7 15.2 P87 87 11.0 4.5 15.5 P88 88 11.5 4.5 16.0 P89 89 12.0 4.2 16.2 *P90 90 12.5 4.0 16.5 P91 91 13.0 4.0 17.0 P92 92 13.5 4.0 17.5 P93 93 14.0 4.0 18.0 P94 94 14.5 4.0 18.5 P95 95 15.0 4.0 19.0 *Default setting
[0087] The operator can change the selected profile using the arrow key 235 before the procedure begins or while the procedure is in progress. If the selected profile is changed, the generator automatically changes the peak temperature and the initial set temperature to the default value. For example, if the selected profile is changed before the procedure begins, the default set temperature is used and the temperature profile behaves similarly to the example above for profile P90, except that the actual values used in the profile will differ according to the selected profile. If the selected profile is changed while the procedure is in progress and the selected profile corresponds to a higher peak temperature, the generator 100 continues to increase the set temperature according to the temperature ramp (e.g., 1° C. every 30 seconds) until reaching the new peak temperature in order to keep a smooth profile that increases temperature quickly with minimal patient discomfort. The dwell timer begins counting once the newly selected peak temperature is reached. If, on the other hand, the selected profile corresponds to a lower peak temperature and the new peak temperature is below the current set temperature, the set temperature value is decreased to the new peak temperature by stopping or reducing the RF energy to the probe and waiting for the actual temperature to decrease to the new peak temperature. The dwell timer begins counting when the new, lower, peak temperature is reached. If the selected profile corresponds to a lower peak temperature and the new peak temperature is above the current set temperature, the generator continues to increase the set temperature according to the ramp (e.g., 1° C. every 30 seconds) until reaching the new, lower, peak temperature. The dwell timer begins counting when the new peak temperature is reached. If the profile is changed to a new profile after the peak temperature has been reached for the current profile, the peak temperature, dwell timer, and other parameters are reset to the values corresponding to the new profile and the new profile is reached as described above.
[0088] The operator can change the set temperature 530 using the arrow keys 230 while the procedure is in progress, typically to manually expedite the temperature ramp by rapidly achieving the initial set temperature. For example, if a P90 profile is selected, the operator can change the set temperature to 80° C. and the generator 100 rapidly achieves the 80° C. setting, e.g., by applying full power until the set temperature is achieved, before starting the temperature ramp of, e.g., 1° C. every 30 seconds from the 80° C. initial set temperature to the 90° C. peak temperature. The set temperature is adjustable by 1° C. for each time a key 230 a , 230 b is depressed. When the set temperature is manually changed, the generator 100 tracks the new temperature. Once the manual setting is complete and the new set temperature is achieved, the generator automatically increases the set temperature 1° C. every 30 seconds until reaching the peak temperature for the selected profile.
[0089] To pause delivery of RF power, the operator presses the RF output on/off control 135 . The generator stops the timer and continues to monitor and display the device parameters. To continue with the automatic temperature profile, the operator presses the RF output on/off control 135 , causing the generator to restart RF delivery with the timer counting from where it left off. The procedure can be reset using soft key 205 , as discussed above. Typically, the reset control 520 may be activated only after a pause in the delivery of RF energy. When reset, the timer re-zeroes, the set temperature 530 returns to the default value, and the set profile 535 remains unchanged. After resetting the procedure, RF delivery is continued by pressing the RF output on/off control 135 .
[0090] FIG. 11 shows an exemplary procedure 1100 for automatic temperature control, which may be used, for example, in the automatic temperature control of the SPINECATH® AUTOTEMP® mode described above or the Decompression AUTOTEMP® mode described below. First, a target temperature is received (step 1105 ). Next, a first set temperature is calculated (step 1110 ). The first set temperature may be calculated by subtracting a predetermined value, e.g. ten degrees, from the default value of set temperature. The default set temperature is usually 65° C. Therefore, the first set temperature typically is 55° C. (i.e., a value that is ten degrees less than the default set temperature of 65° C.).
[0091] Next, the generator 100 commands a first output power level (step 1115 ). The first output power level typically is full power. The generator receives a measured temperature (step 1120 ). If the generator determines that the measured temperature is less than the first set temperature (step 1125 ), then the generator waits a first predetermined period, e.g., 400 ms, (step 1130 ) and repeats steps 1120 , 1125 and 1130 until the measured temperature is equal to (or has exceeded) the first set temperature (e.g., 55° C.).
[0092] Once the generator determines that the measured temperature is equal to (or has exceeded) the first set temperature (step 1125 ), e.g., 55° C., the generator commands a second power output level (step 1135 ). The second power level usually is a power level that will cause a temperature increase according to a desired temperature ramp profile, e.g., 1° C. every 30 seconds. The second power output level typically is less than the first power output level of step 1115 . Thus, the temperature increases more slowly and in a controlled manner according to a temperature ramp profile at this point onward in the procedure 1100 .
[0093] Next, the generator 100 calculates an updated set temperature (step 1140 ). The updated set temperature is calculated, e.g., by adding a pre-selected amount (e.g., one degree) to the first set temperature. The generator receives a measured temperature 1145 . If the generator determines that the measured temperature is less than the updated set temperature (step 1150 ), the generator waits a second predetermined period of time, e.g., 400 ms (step 1155 ) and repeats steps 1145 , 1150 , and 1155 until the measured temperature is equal to the updated set temperature.
[0094] Once the generator determines that the measured temperature is equal to or greater than the updated set temperature, a determination is made as to whether the updated set temperature is equal to the target temperature (step 1160 ). If the updated set temperature is not equal to the target temperature, a new updated set temperature is calculated (step 1165 ). Typically, the new updated set temperature is calculated as described above with respect to the updated set temperature in step 1140 . The new updated set temperature is used in steps 1145 - 1160 . In another implementation, the set temperature is not updated and is equal to the target temperature.
[0095] Steps 1145 - 1160 are repeated until the updated set temperature is equal to the target temperature. Then, the target temperature is maintained (step 1175 ). Typically, the target temperature is maintained for the pre-selected dwell time according to temperature profile selected for the given procedure.
[0096] In another implementation, a control routine such as, for example, a PI or a PID routine can be used to adjust the output voltage to control to the measured temperature to achieve the set temperature.
[0097] FIG. 12 shows an exemplary procedure 1200 for automatic temperature control which may be used, for example, in automatic temperature control of the SPINECATH® AUTOTEMP® mode described above or the Decompression AUTOTEMP® mode described below. A target temperatures is received (step 1205 ). Next, a first output level is delivered (step 1210 ). The first output level can be chosen based upon a recognized probe that is connected to the generator 100 . Next, a temperature measurement is received (step 1215 ). The probe is able to measure a temperature, or the temperature measurement may be received from a different source.
[0098] A test is made to determine whether the measured temperature is within a specified value of the target temperature (step 1220 ). The specified value may be stored by the generator, retrieved by the generator, or calculated by the generator. In one example, the specified value may be 1° C. The specified value can vary, for example, depending upon the identity of the probe that is connected to the generator 100 . If the measured temperature is not within the specified value (e.g., 1° C.) of the target temperature, the first power output level continues to be delivered until the measured temperature is within the specified value of the target temperature.
[0099] If the measured temperature is within the specified value of the target temperature, then a control algorithm is used to control power delivery by the generator (step 1225 ). The control algorithm calculates a second power level and controls the generator power delivery so as to make the measured temperature equal to the target temperature. The control algorithm can be a PID algorithm, a PI algorithm, or other suitable control algorithm. The control algorithm can control, for example, the output power or the output voltage of the generator 100 .
[0100] In implementations using a PID (proportional-integral-derivative) control algorithm, the coefficient of the derivative term can be set to zero so that the control algorithm uses only the proportional and integral terms. In other implementations, the coefficient of the derivative term is non-zero and the control algorithm uses the derivative, proportional, and integral terms.
[0101] Also, the control values of the PID control algorithm can be pre-loaded with a starting value for the second output power level. Pre-loading a starting value for the second output power level allows for a smooth transition between the first output level and the second output level. Thereafter, the second output level typically is calculated by the control algorithm. Using a pre-loaded value for the second output level helps to ensure a more continuous transfer between the first and the second output levels. The starting value for the second output power can be derived, for example, by measuring the steady state output of the generator once the measured temperature is equal to the target temperature. The steady-state output can be measured for each type of probe that will be connected to the generator, and thereafter used as a base point for the pre-loaded value.
[0102] If the starting value for the second output level is too low, the measured temperature will drop some during transition between the first output level and the second output level, leading to an increased time required to achieve the target temperature. A low starting value also may lead to oscillations about the target temperature. Also, if the starting value is too high at the point of transition, the measured temperature can exceed the target temperature for a period of time until the control algorithm can reduce the output of the generator.
[0103] Each device used with the generator can have its own preload value for the second output level. In one example, the preloaded value is not adjusted for changes in target temperature. In another example, the preloaded value is calculated so to improve the algorithm performance. The pre-loaded value can differ depending upon the identity of the probe connected to the generator 100 . The pre-loaded value can be stored in a computer readable format, or can be calculated based upon the target temperature.
[0104] Finally, the control algorithm is used to maintain the target temperature (step 1230 ).
[0105] FIG. 13 shows an exemplary procedure 1300 for automatic temperature control which may be used, for example, in automatic temperature control of the SPINECATH® AUTOTEMP® mode described above or the Decompression AUTOTEMP® mode described below. In the example of FIG. 13 , the RF output of the generator 100 is controlled by a digital to analog converter (DAC). In one implementation, the output value of the DAC ranges from 0 to 4095. Other output values of the DAC may be used.
[0106] A target temperature (TARGET_TEMP) is received (step 1305 ). Next, a maximum DAC setting (MAX_DAC) is received (step 1310 ). The MAX_DAC value is chosen for the particular probe being used, and the probe is installed in the electrosurgical generator 100 . A check is made to determine whether RF output is activated for the generator 100 (step 1315 ). If the RF output is activated, then a RAMP_FLAG is set to TRUE (step 1320 ).
[0107] A check is made to determine: (1) if the RAMP_FLAG is set to TRUE and; (2) if the difference between the target temperature (TARGET_TEMP) and the actual temperature (ACTUAL_TEMP) is greater than 1° C. (step 1325 ). If both are true, then the maximum DAC setting (MAX_DAC) is delivered (step 1330 ). A check is made to determine if the power output is less than the maximum power output allowed for the particular probe connected to the electrosurgical generator (step 1335 ). The probe connected to the generator 100 may be identified, for example, in a manner similar to that discussed above with respect to the probe recognition step (step 410 ) of FIG. 4 . After the probe is identified, a maximum power output corresponding to that probe may be retrieved from a storage location or dynamically computed. If the TARGET_TEMP and ACTUAL_TEMP difference is more than 1° C., then the maximum DAC setting (MAX_DAC) is increased by a value, such as 5 (step 1340 ). On the other hand, if the power is not less than the maximum allowed power for the particular probe connected to the generator, then a test is made to determine whether the power is more than the maximum allowed power for the device (step 1345 ). If the power is more than the maximum power allowed for the device, then the maximum DAC setting (MAX_DAC) is decreased by a value such as 5 (step 1350 ). If on the other hand, the power is not more than the maximum power allowed by the device, then a test is again made to determine whether the power is less than the maximum allowed power (step 1335 ).
[0108] Referring again to step 1325 , if the difference between the TARGET_TEMP and the ACTUAL_TEMP is not greater than 1° C., then the RAMP_FLAG is set to FALSE (step 1355 ). Next, the output of the generator 100 is set to the initial DAC control level defined for the specific probe connected to the generator 100 (step 1360 ). Next, the DAC output is set to a calculated value (step 1365 ). The calculated value may be, for example, a value equal to Ki*ERROR Integral +Kp*ERROR, where the ERROR is the difference between TARGET_TEMP and ACTUAL_TEMP, and where Ki and Kp are defined for the specific probe connected to the electrosurgical generator.
[0109] Next, a test is made to determine whether the set value of the DAC output exceeds the MAX_DAC (step 1370 ). If the set value of DAC output exceeds the MAX_DAC, then the output is limited to the MAX_DAC (step 1375 ). On the other hand, if the set value of the DAC output does not exceed the MAX_DAC, then a test is made to determine whether the set value of the DAC output is less than 0 (step 1380 ). If the set value of the DAC output is less than 0, then the output is limited to 0 (step 1385 ). If, on the other hand, the set value of the DAC output is not less than 0, then a test is made to determine whether the set value of the DAC output equals the MAX_DAC (step 1390 ). If the set value of the DAC output equals the MAX_DAC, then the ERROR value, which is the difference between the TARGET_TEMP and the ACTUAL_TEMP is not integrated in the computation of the DAC output described above with respect to step 1365 (step 1295 ).
[0110] Decompression AUTOTEMP® Mode
[0111] Referring to FIG. 6 , when the recognized probe is a Decompression catheter, the generator enters Decompression AUTOTEMP® mode and user interface (UI) 600 is presented to the operator on display 115 . User interface 600 indicates the generator mode as the Decompression mode 605 . Several parameters for the Decompression mode are displayed to the operator. For example, measured probe impedance 610 , elapsed procedure time 615 , actual probe temperature 625 , set temperature 630 , and set profile 635 . A reset control 620 is activated by soft key 205 . The set temperature 630 can be changed by manipulation of arrow keys 230 and the set profile 635 can be changed through manipulation of arrow keys 235 . An example of possible Decompression AUTOTEMP® profiles are illustrated in Table 2. Table 2 shows the selected profile, the peak temperature, the time to achieve the peak temperature, dwell time, and the total treatment time. The decompression auto-temperature mode default profile is shown as profile “P90.” In a similar manner to that discussed above with respect to FIG. 5 , the generator 100 automatically increases the temperature in a controlled manner from the initial set temperature to the peak temperature, and then dwells at the peak temperature. Energy delivery stops automatically at the completion of the profile.
TABLE 2 Peak Total Treatment Selected Temperature Time to Peak Dwell Time Time Profile ° C. (min.) (min.) (min.) P80 80 3.0 6.0 9.0 P81 81 3.3 6.0 9.3 P82 82 3.6 6.0 9.6 P83 83 3.9 6.0 9.9 P84 84 4.2 6.0 10.2 P85 85 4.5 6.0 10.5 P86 86 4.8 6.0 10.8 P87 87 5.1 6.0 11.1 P88 88 5.4 6.0 11.4 P89 89 5.7 6.0 11.7 *P90 90 6.0 6.0 12.0 P91 91 6.3 6.0 12.3 P92 92 6.6 6.0 12.6 P93 93 6.9 6.0 12.9 P94 94 7.2 6.0 13.2 P95 95 7.5 6.0 13.5
[0112] The set temperature 630 default typically is 50° C. for the start of the automatic 5 temperature ramp for the decompression automatic temperature mode. The set profile default of P90 corresponds to a peak temperature of 90° C. as shown by Table 2. To begin delivery of the RF power, the operator presses RF output on/off control 135 and the elapsed procedure time clock 615 begins counting up. Once the delivery of the RF power has begun and the initial set temperature of 50° C. is achieved, the temperature is increased at a rate corresponding to a desired temperature ramp, e.g., 1° C. every 6 seconds, from 500 to a value of 80° C. Above 80° C., and until reaching the peak temperature of 90° C. for the selected P90 profile, the temperature is increase at a different desired temperature ramp, e.g., a rate of 1° C. every 18 seconds. Thus, the temperature ramp changes slope at a certain point so as to increase the temperature more slowly as the actual temperature approaches the peak temperature value. This change in temperature ramps will reduce the possibility of overshooting the peak temperature and enhances patient comfort. Upon reaching the peak temperature, the generator holds the peak temperature for a dwell time of a predetermined duration as shown in Table 2.
[0113] The values for the temperature profiles in the Decompression AUTOTEMP® mode typically differ from the values for the temperature profiles in the SPINECATH® AUTOTEMP® mode due to differences in the probes used for each mode. As with the SPINECATH® AUTOTEMP® profiles, the Decompression AUTOTEMP® profiles are derived experimentally and balance speed of achieving the peak temperature against patient comfort.
[0114] The operator can change the set profile before or during power delivery by pressing arrow keys 235 . As described above with respect to the SPINECATH® automatic temperature mode of FIG. 5 , when the set profile is increased during the procedure, the generator 100 increases the set temperature according to a temperature ramp (e.g., 1° C. every 18 seconds) until reaching the new peak temperature. The dwell timer begins counting when the new peak temperature is reached. When the set profile is decreased and the new peak temperature is below the current set temperature, the set temperature value is changed to the new peak temperature and the new peak temperature is achieved as described above. The dwell timer begins counting when the new peak temperature is reached. When the set profile is decreased and the current set temperature is below the peak temperature, the generator 100 continues to increase the temperature according to the profile (e.g., 1° C. every 18 seconds) until reaching the new peak temperature. The dwell timer begins counting when the new peak temperature is reached. When the set profile is changed after the peak temperature for the current profile has been reached, the peak temperature, dwell duration timer, and other parameters are reset to the values corresponding to the new profile and the new peak temperature is achieved as described above.
[0115] The set temperature 630 can be manually changed during the auto-temperature routine using arrow keys 230 . The set temperature is adjustable by 1° C. for each time the key is pressed. The temperature range typically ranges from 50° C. to the peak temperature of the selected profile. The set temperature 630 can be used, for example, to manually expedite the temperature ramp. When the initial set temperature is manually changed, the generator tracks the new set temperature and will rapidly achieve the new set temperature by, for example, applying full power until the new set temperature is reached. Once the manual setting is complete and the generator has achieved the new set temperature, the generator automatically increments the set temperature according to a desired temperature ramp (e.g., 1° C. every 6 seconds if the new set temperature is from 50° C.-80° C. and 1° C. every 18 from a set temperature of 80° C. onward) until reaching the peak temperature for the selected profile.
[0116] The automatic temperature routine can be paused by depressing the RF output on/off control 135 , and can be resumed by pressing RF output on/off control 135 again. Upon the continuation of the procedure, the RF power delivery commences and the timer begins counting from where it left off. The procedure can be reset by activating the reset control 620 , which is activated by soft key 205 . This reset action resets the timer to zero and set temperature to the default value, and leaves the profile selection unchanged. RF power delivery can be continued by pressing the RF output on/off control 135 .
[0117] Sensory Stimulation Mode
[0118] Referring to FIG. 7 , when the recognized probe is a denervation probe, the generator enters sensory stimulation mode and user interface (UI) 700 is presented to the operator on display 115 . User interface 700 indicates the generator mode as the Sensory Stimulation mode 705 . The sensory stimulation mode is one of two stimulations modes, sensory stimulation and motor stimulation, and each has its own default parameters. The sensory stimulation mode stimulates sensory nerves to cause a pain sensation in the patient, and the motor stimulation mode stimulates motor nerves that cause muscle movement in the patient. The stimulation modes are used to confirm proper placement of a probe in a denervation or other pain management procedure.
[0119] Upon connection of a denervation probe, the generator 100 defaults to the sensory stimulate mode as shown in UI 700 . In sensory stimulation, the frequency typically defaults to 50 hertz and the pulse width defaults to 1 millisecond. The stimulation output voltage typically defaults to zero volts and is displayed as “off.” Once the stimulate mode is activated, the output voltage typically starts at zero volts and may be incremented by operator action.
[0120] UI 700 shows the sensory stimulation mode 705 , which includes parameters such as measured probe impedance 710 , stimulation volts 730 , frequency 735 , pulse width 740 , and controls the switching between other modes including the motor stimulation mode 715 , pulsed RF mode 720 , and RF lesion mode 725 . The mode may be switched between the sensory stimulation and the motor stimulation modes by activation of soft key 205 . The motor stimulation mode is shown and described with respect to FIG. 8 . The mode may be changed between the sensory stimulation mode and the pulsed RF mode by activating soft key 215 . The pulsed RF mode is shown and described with respect to FIG. 10 . The mode may be changed between the sensory stimulation mode and the RF lesion by activating soft key 220 . The RF lesion mode is shown and described with respect to FIG. 9 . When switching between modes, a user modified parameter may be retained.
[0121] After placing the probe in the patient, the rotary encoder knob 150 is pressed once to turn the voltage on. The stimulation volts display 730 will change from “off” to zero volts. The rotary encoder knob 150 is then turned clockwise to increase the stimulate voltage from zero volts up to a maximum of 1 volt. The width of the stimulate pulses 740 may be changed using the arrow keys 235 . The pulse width may be adjusted to 0.1, 0.5, 1, 2, or 3 milliseconds. In another implementation, the pulse width is not adjustable. The frequency of the pulses is typically 50 hertz for the stimulation mode 735 and is not adjustable. The voltage may be turned off by depressing the rotary encoder knob 150 . Thus, the rotary encoder knob 150 acts as a “radio knob” with complete on/off and voltage increase and decrease control. Sequentially pressing the rotary encoder knob 150 toggles voltage between off and active. The active voltage is typically restarted at zero volts when switching between off and active states. When active, the voltage may be incremented up from zero volts by operator action. The voltage range for the sensory stimulation mode typically is 0-1 volt, and the pulse width range typically is 0.1, 0.5, 1, 2, and 3 milliseconds. In another implementation, the pulse width is not adjustable.
[0122] Motor Stimulation Mode
[0123] Referring to FIG. 8 , if the operator enters motor stimulation mode from sensory stimulation mode, user interface (UI) 800 is presented to the operator on display 115 . User interface 800 indicates the generator mode as the Motor Stimulation mode 805 .
[0124] The UI 800 includes parameters such as stimulation volts 825 , frequency 830 , and pulse width 840 . Indications are also provided to switch to a different mode including the stimulation sensory mode 810 , the pulsed RF mode 815 , and RF lesion mode 820 . These controls are activated by using soft key 205 to switch to the sensory mode 810 , soft key 215 to switch to the pulsed RF mode 815 , and soft key 220 to switch to the RF lesion mode 820 .
[0125] After the probe is placed in the patient, the rotary encoder knob 150 is pressed once to activate the voltage output. The output voltage defaults to 0 volts at a default pulse width value therapy profile. The rotary encoder knob 150 then is turned clockwise to increase the motor stimulate voltage from zero volts up to a maximum value, which typically is 10 volts. The width of the stimulate pulses may be changed using the arrow keys 235 . The pulse width may be adjusted to 0.1, 0.5, 1, 2, or 3 milliseconds. In another implementation, the pulse width is not adjustable. The frequency of the pulse is fixed at 2 hertz for the motor stimulate mode. The voltage may be turned off at any time by depressing the rotary encoder knob 150 . Sequentially depressing the rotary encoder knob 150 toggles the voltage between active and off. The active voltage is restarted at 0 volts, and may be incremented by the operator. The voltage range for the motor stimulation mode typically is 0-10 volts, the pulse width typically is adjustable but frequency typically is not, and the pulse width range typically is 0. 1, 0.5, 1, 2, and 3 milliseconds.
[0126] RF Lesion Mode
[0127] Referring to FIG. 9 , if the operator enters RF Lesion Mode from the sensory or motor stimulation mode, user interface (UI) 900 is presented to the operator on display l l 5 . User interface 900 indicates the generator mode as the RF Lesion mode 905 . The RF Lesion mode is used to destroy tissue in a denervation procedure once the probe has been properly placed. In this mode, the generator automatically controls the power to reach and maintain a selected temperature for a selected time.
[0128] The UI 900 includes parameters such as measured probe impedance 910 , elapsed procedure time 915 , actual probe temperature 935 , set temperature 940 , and set time 945 . Controls are also provided to reset the mode 920 , and to switch to other modes including the sensory stimulation mode 925 and the motor stimulation mode 930 . The reset control is activated by soft key 205 , switching to the sensory mode is done using soft key 215 , and switching to the motor stimulation mode is done using soft key 220 .
[0129] The actual probe temperature reads room temperature if the probe is in free air and body temperature if the probe is inside the patient. The measured probe impedance 910 reads between 0 and 999 ohms when the denervation probe is placed in the patient. The set temperature 940 default is 80° C. for the RF lesion mode. The set temperature may be selected in a range from approximately 50° C. to 90° C. using arrow key 230 . The default set time value for the RF lesion mode is 90 seconds. The timer may be set to 30, 60, 90, or 120 seconds using arrow key 235 .
[0130] To begin delivery of the RF power to the probe, the operator presses the RF output on/off control 135 . The elapsed procedure time display starts counting up when the RF power delivery begins. RF power delivery ceases when the elapsed procedure time reaches the set time. The RF lesion mode is exited by pressing one of the soft keys 120 across the bottom of the display that correspond to sensory stimulation mode 925 and the motor stimulation mode 930 , to switch to the respective mode.
[0131] When the set temperature 940 is increased by the operator, the generator increases the actual temperature until reaching the new set temperature. When the set temperature 940 is decreased by the operator, the generator decrease the actual temperature by decreasing or stopping the RF power delivery until the actual temperature reaches the set temperature. The set time 945 may be changed by the operator to change the RF deliver time. Typically, RF power delivery is paused by pressing the RF output on/off control 135 prior to changing the set time 945 . If the probe 165 is repositioned during the pause, typically the operator returns to the stimulate mode to confirm that the probe is positioned correctly prior to recommencing the denervation procedure. Upon leaving the stimulate mode and returning to the RF lesion or pulsed RF mode, the timer resets to zero. While paused, the timer may be reset by pressing the reset soft key 205 to operate control 920 . This reset action will reset the elapsed procedure time and leave the set temperature selection unchanged, RF power delivery may then be continued by pressing the RF output on/off control 135 .
[0132] For the RF lesion mode, the set time typically is adjusted for 30, 60, 90, and 120 seconds. The default time is usually 90 seconds. The RF lesion mode set temperature range normally is 50° C. to 90° C.
[0133] Pulsed RF Mode
[0134] Referring to FIG. 10 , if the operator enters Pulsed RF Mode from sensory or motor stimulation mode, user interface (UI) 1000 is presented to the operator on display 115 . User interface 1000 indicates the generator mode as the Pulsed RF mode 1005 . The Pulsed RF mode is used to denature nervous tissue by exposing it to voltage.
[0135] UI 1000 includes parameters such as measured probe impedance 1010 , elapsed procedure time 1015 , actual probe temperature 1040 , RF volts 1035 , frequency 1045 , set temperature 1050 , and set time 1055 . Controls are also provided to reset 1020 the timer, and to switch to other modes including the sensory stimulation mode 1025 and the motor stimulation mode 1030 . In Pulsed RF mode, the temperature defaults to 42° C., the set time defaults to 2 minutes, the frequency defaults to 2 hertz, and the RF voltage displays zero.
[0136] In the Pulsed RF mode, the generator delivers pulsed RF energy to reach and maintain the selected set temperature for the set time. Typically, the RF pulses are approximately 20 ms in duration. The amplitude, frequency and/or pulsewidth of the pulses can be automatically adjusted to maintain the specified set temperature. In one implementation, the pulse width is not adjustable. The RF output on/off control 135 is pressed to begin delivery of RF power. The actual probe temperature reads room temperature if the probe is in free air or body temperature if the probe is placed in the patient. The measured probe impedance typically reads between 80 and 999 ohms when the denervation probe is placed in the patient. The set temperature typically is selected from a range of 35° C. to 50° C. using arrow keys 230 . The frequency typically may be set to 1, 2, 4, or 8 hertz using arrow keys 225 . The set time may be set to 1, 2, 3, 4, or 5 minutes using arrow keys 235 .
[0137] The elapsed procedure time display 1015 starts counting up when the RF power delivery begins. The RF power delivery ceases when the elapsed procedure time reaches the set time. The Pulsed RF mode may be exited by pressing one of the soft keys on the bottom of the display corresponding to the sensory stimulation mode 1025 and the motor stimulation mode 1030 . When the set temperature is increased in the pulsed RF mode, the rate of increase in temperature varies depending upon the current frequency setting. The temperature increases more slowly with a low frequency setting and more rapidly with a higher frequency setting. The rate of temperature increase typically is a function of the duty cycle of the power applied and is directly related to the frequency of pulses. When the set temperature is decreased the generator decreases the actual temperature to the set temperature by reducing or stopping the RF energy output.
[0138] RF power delivery may be paused by pressing the RF output on/off control 135 . When the RF output on/off control 135 is pressed again, RF power delivery resumes. If the probe is repositioned during the pause, then the operator typically returns to the stimulate mode to confirm that the probe is properly placed prior to recommencing denervation. Upon leaving the stimulate mode and returning to the RF lesion or pulsed RF mode, the timer resets to zero. While paused, the timer may be reset 1020 by pressing the reset soft key 205 . This action resets the elapsed procedure time and leave the set temperature selection unchanged. RF power delivery may then be continued by pressing the RF output on/off control 135 . The set time may be changed while RF power delivery is paused using the arrow keys 235 .
[0139] For the Pulsed RF mode, the set time is usually adjustable from 1 to 5 minutes. The default duration normally is 2 minutes. The Pulsed RF mode set temperature range typically is 35° C. to 50° C.
[0140] A number of implementations have been described. Nevertheless, it will be understood that various modifications may be made. For example, in the SPINECATH® AUTOTEMP® mode and the Decompression AUTOTEMP® mode, the initial set temperature and/or the first set temperature may have a different default value for each of the different profiles. The initial set temperature and/or the first set temperature may be a fixed, pre-stored value, or it may be calculated dynamically. For example, the initial set temperature may be calculated dynamically by subtracting a predetermined value from the target temperature or by subtracting a predetermined value from the default set temperature. Also, the updated set temperature may be calculated by subtracting a pre-selected amount, e.g., ten degrees, from the target temperature or by adding a selected amount, e.g., one degree, to the initial set temperature or the first set temperature. Furthermore, other controls may be used. For example, other controls such as a switch and/or a dial may be used in place of the soft keys and the arrow keys.
[0141] In procedure 1100 , certain steps may be omitted or the order of steps may be changed. For example, steps 1130 and/or 1155 maybe omitted. Also, the updated set temperature may be calculated (step 1140 ) prior to commanding the second power output level (step 1135 ).
[0142] The generator typically uses an input power source of 100-120 volts AC or 200-240 volts AC, 50 or 60 hertz. The output power is a maximum of approximately 20 watts into a 90-250 ohm load. The output power is 0-5 watts when the generator is used with the SPINECATHφ Intradiscal Catheter, 0-3 watts when the generator is used with the Decompression Catheter, and 0-20 watts when the generator is used for denervation with the RF Denervation Probe. The maximum output voltage is 160 volts RMS. In the stimulate mode, the maximum output is 10V peak. The generator uses a sine wave for the RF lesion and pulsed RF modes, and a square wave for the stimulate modes.
[0143] Accordingly, other implementations are within the scope of the following claims. | A method includes recognizing an electrosurgical probe coupled to an electrosurgical generator, selecting a mode of the electrosurgical generator based upon the recognized probe, setting a therapy profile based upon the selected mode, and displaying the therapy profile. The generator can include user inputs for modifying the therapy profile. A computer implemented method for achieving a target temperature includes: a) receiving the target temperature; b) calculating a first set temperature; c) commanding a first output power level until a measured temperature is equal to or greater than the first set temperature; d) calculating an updated set temperature based upon the target temperature; e) commanding a second output power level until the measured temperature is equal to or greater than the updated set temperature; and repeating d and e until the updated set temperature is equal to the target temperature. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to reducing the amount of fluid normally maintained in the bottom of a tank and, specifically, reducing the amount of undrawable oil located below the top edge of the suction line in an oil storage tank.
2. Description of the Prior Art
In the modern world the storage of petroleum, both crude and refined, is an important part of efficient energy management. The typical oil storage tank, whether fixed or floating roof, has an inlet pipe and intake valve located in the side of the tank near the bottom and a corresponding suction line and delivery valve also located in the side near the bottom of the tank. The tank bottom is generally sloped downwardly toward the middle to collect water and other sediment, which settles out during storage. A valved water draw off line is connected to the lowermost point in the tank so that water and sediment that has collected can be periodically removed. The suction line or outlet is round and may be typically one to three feet in diameter. It is located with its bottom edge as close to the bottom of the tank as is consistent with ensuring that no water or sediment enters the suction line, usually about one foot is sufficient. When drawing off the stored oil, the oil level can not be permitted to fall below the top edge of the suction line, otherwise the pump will suck air and other vapors in the tank and lose its prime, thereby becoming vapor locked, and be ineffective. Therefore, there exists at the bottom of all oil storage tanks a layer of oil, of a depth at least equal to the diameter of the suction line, with reasonable margins above and below. This layer of oil is typically up to four feet deep and is not available for use during the period the tank is in service. This is the deadstock or undrawable bottoms. Only at the time that the tank is totally drained through the water drawoff line can this oil be recovered and made available for use. Such draining takes place only about once every five years when the tank is emptied and cleaned. As soon as the tank goes back into service, the deadstock is there again. Given the large size of most oil storage tanks and an approximate price of $30 a barrel, it can be easily seen that vast amounts of oil worth millions of dollars are presently represented by these "undrawable bottoms" or "heels" in the bottoms of the existing oil storage tanks. The present requirement to maintain a relatively large inventory due to uncertainties of availability and price is in no way assisted by this deadstock, since it is undrawable and, therefore, not available to meet product demands.
OBJECTS AND SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide method and apparatus for use with bulk oil storage tanks that reduce the volumes held as undrawable bottoms.
It is another object of the present invention to reduce the volumes of oil held as undrawable bottoms in bulk storage by adding a volume displacement device at the bottom of the tank, without impeding required tank operations.
It is a further object of the present invention to reduce the volume of oil held as undrawable bottoms in bulk storage tanks by specially sized or specially oriented suction lines.
It is also an object of the present invention to provide apparatus to reduce the amount of oil held as undrawable bottoms that may be incorporated in newly fabricated bulk storage tanks or that may be retrofitted to existing tanks, either when they are removed periodically from service for maintenance and cleaning or while they are still in service.
In one aspect of the present invention, a positive displacement device is arranged in the bottom of a bulk storage tank to displace the volume of oil normally held below the top edge of the suction line and the bottom of the tank that was previously undrawable. The inventive apparatus includes structural elements to permit water and sediment to be drawn off from the bottom of the tank in the conventional fashion and also provides structural elements to prevent occluding the suction line during delivery of the oil in storage. The displacement device can comprise a closed hollow disc structure to displace the oil or a tray-like structure to hold water, clay bricks, or plastic spheres or containers filled with water or sand or the like. In all cases the oil intake line, the suction line and the water draw off line must remain unobstructed.
In another aspect of the invention, coffer dams are arranged around the intake and suction lines; the volume defined by the coffer dams and the bottom of the tank is then filled with water or other inert material. The water level is monitored and adjusted periodically to maintain it below the height of the coffer dam. The stored oil occupies the volume above the controlled level of the water and spills over the coffer dam to keep the suction well around the suction line full of oil at all times.
The invention also provides a means of utilizing previously undrawable bottoms by altering the size and arrangement of the suction line or delivery line, particularly when a tank cannot be removed from service for internal modifications. The quantity of deadstock in the undrawable bottom is a function of the location of the top of the suction line and, therefore, the vertical dimensions of the suction line. The present invention provides method and apparatus to lower this location in relation to the bottom of the tank by providing a flattened delivery tube that has approximately the same cross sectional area as the original round delivery line but because of the flattened profile, the lowered top reduces the thickness of the deadstock layer. The invention also contemplates use of a plurality of smaller diameter delivery lines so arranged that the lowest points on these lines are at the same level as the low point of the original delivery tube and are connected through a manifold or header to the suction pump.
The manner in which these and other objects are accomplished by the present invention will be explained in relation to the following detailed description and drawings, wherein like reference numerals denote like parts.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic representation in cross section of a storage tank according to one embodiment of the present invention;
FIG. 2 is a schematic representation in cross section of a storage tank according to another embodiment of the present invention;
FIG. 3 is a schematic representation of a top plan view of the tank of FIG. 2;
FIG. 4 is a schematic representation in cross section of a floating roof storage tank according to an embodiment of the invention;
FIG. 5 is a schematic representation in cross section of a storage tank according to another embodiment of the invention;
FIG. 6 is a schematic representation in cross section of a storage tank employing the coffer dam embodiment of the present invention;
FIG. 7 is a top plan view in cross section of the embodiment of FIG. 6;
FIGS. 8A, 8B, and 8C are schematic representations of suction or delivery lines for use in a storage tank according to the present invention; and
FIG. 9 is another schematic representation of suction lines for use according to the present invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
Referring now to FIG. 1, an oil storage tank 10 is shown having an embodiment of the present invention installed therein. Bulk storage tank 10 is of the conventional kind having a valved intake line 12 and a valved delivery or suction line 14. It is known practice to slope the bottom of the tank toward the center, as shown at 16, and to provide a valved outlet line 18 connected to the lowest point in the tank bottom. The sloped bottom 16 serves to collect water and sediment in the tank, so that it may be drained off through line 18.
The amount of oil in tank 20 according to known procedures that constitutes the undrawable bottom is defined by the top edge 20 of outlet line 14 and the bottom edge 24 of outlet line 14 and reasonable operating margins above and below these edges. It is not an acceptable solution to simply lower the location of delivery line 14, since the volume below the lower edge 24 of delivery line 14 must be maintained to accumulate water and sediment and the like between the times that such is drawn off by line 18.
This volume heretofore occupied by deadstock is filled according to the present invention by a closed metal disc 26 that is hollow and fluid tight. The hollow disc 26 rests on the tank bottom 16 by means of several legs or supports, shown typically at 28. The top surface 30 of the hollow metal disc 26 is sloped gently upwardly so that water and sediment in the oil will not reside upon the hollow metal positive displacement disc 26.
Disc 26 has the same diameter as the tank, except that an adequate clearance space is provided in front of delivery tube 14, thus providing a suction well inside the tank around delivery tube 14. It is necessary that these tubes not be obstructed and to further assist smooth fluid flow to the suction line, the side walls 32 of disc 26 are sloped generally inwardly. A similar intake well is provided around the intake tube 12, or the intake tube 12 can be relocated upwardly.
FIG. 2 shows another embodiment of the present invention in which in place of the closed hollow disc of FIG. 1, structure 40 or tray filled with water or other solid inert material is provided. This fluid filled tray 40 again serves to displace the oil that would normally be deadstock in the volume of tank 10 defined by the top edge 20 of delivery tube 14 and the bottom edge 24 of the delivery tube. The interior of structure 40 is in communication with a valved fill/drain pipe 42 so that structure 40 can be filled with water to occupy the volume previously occupied by deadstock. A sight glass or gauge glass 44 may be provided so that the level of fluid in structure 40 can be monitored. Once again it is necessary to maintain the delivery tube 14 free from obstructions, and the overflow weir 46 of structure 40 is slanted inwardly to provide adequate clearance for fluid flow. This embodiment may similarly have a provision to keep the area around oil intake line 12 free of obstruction or the line may be relocated above the level of water in the tray. A central drain 50 may be provided to permit excess water flow to the bottom of the tank to be ultimately drawn off. The level of water in the tray is determined by the height of the central drain 50 and may be set slightly lower than the overflow weir 46, so that within structure 40, there always remains a thin layer of oil on top of the water level with additional volumes of oil spilling over the overflow weir 46 to fill the suction well around delivery outlet 14. Structure 40 can be supported by legs or supports, shown typically at 52.
FIG. 3 is a top plan view of the storage tank of FIG. 2. and shows the section lines 2--2 along which the cross-sectioned view of FIG. 2 is taken. The overflow weir 46 has a corresponding inlet cutout 60 also formed in tray 40 in order to maintain free access for the liquid relative to oil inlet tube 12. Specifically, cutout 60 is formed in tray 40 at the location of inlet line 12, and cutout 46 is formed in tray 40 at the location of delivery line 14. Each of these cutouts 46, 60 is formed as a weir, with the edges thereof being slightly higher than the top of central overflow drain tube 50, in this fashion a thin layer of oil is formed on top of the water held in tray 40 and the suction well around delivery tube 14 remains free of water and filled with oil. The tray 40 is attached at its periphery to the inside of tank 10, as seen in FIG. 3. The need for providing cutout 60 can be avoided by repositioning the oil inlet tube 12 above the level of water in tray 40.
All of the above described bulk storage tanks have been of the fixed roof kind, however, there is at least one other kind of bulk storage tank adaptable for use according to the present invention, e.g., the floating roof bulk storage tank. In this kind of tank the position of the top or roof of the tank is adjusted vertically depending upon the volume of fluid stored therein. One such floating roof tank according to the present invention is shown in FIG. 4, and the floating roof 70 is movable in the vertical direction in relation to the tank 72 and is in sealing relation therewith in the conventional fashion, as represented typically at 74. A positive displacement element 76 is arranged in the bottom of the tank at the location normally occupied by the deadstock and, in the example in FIG. 4, the positive displacement element is the closed hollow disc 26 of FIG. 1. Any of the other embodiments of the positive displacement element described herein could also be employed. Because the floating roof 70 can move downwardly to such an extent as to interfere with the closed hollow disc, standoffs or supports 78 are affixed to the lower inner surface of floating roof 70. By means of these standoffs, when the floating roof 70 is at its lowermost point of travel, it will be limited and supported by the positive displacement element 76, that has its own supports or legs, shown typically at 80.
All of the heretofore described embodiments to lessen the volume of deadstock in bulk storage tanks require taking the tank off line, cleaning it, entering it with personnel and constructing the modification. In FIG. 5 an embodiment of the present invention is shown that does not require taking the tank off line and that can be modified to lessen the amount of deadstock by inserting elements through a hatch (not shown) in the top of the tank. More specifically, the amount of deadstock in tank 10 is reduced as much as possible by filling the space normally occupied by the deadstock with positive displacement elements, these elements being inserted into the oil contained in tank 10 and allowed to sink to the bottom of the tank. In this embodiment the deadstock volume is occupied by plastic or neoprene rubber spheres filled with water, shown typically at 86. The water-filled plastic sphere 86 is only one embodiment, and there are many equivalents that could be employed following the present invention. As in the previously described embodiments, it is necessary to prevent the outlet or delivery tube 82 from being occluded, as well as keeping the water drain line 84 and oil intake line 86 free. To accomplish this the invention provides shields or guards that may be either inserted through the hatch in tank 10 and appropriately arranged or the shields may be inserted through the tube or line that they are protecting, in which case, the shield would be of a partially collapsible nature. Specifically, shield 88 is arranged in front of delivery line 82 in order to prevent the positive displacement devices 86 from obstructing the line. Similarly, shield or guard 90 is arranged in front of water drawoff line 84 and shield 92 is arranged in front of intake line 86. These shields, 88, 90, and 92 are constructed as a frame work that permit oil and water to flow through, yet will prevent the positive displacement means from obstructing fluid flow. Note that the insertion of the shield into the tank through the respective fluid line is made possible because these lines are substantial in size. Although the figures herein are not to scale, the delivery line 82 is typically one to three feet in diameter.
The above-described embodiments of the invention have all relied upon the insertion or addition of positive displacement structures into the tank to replace the deadstock volume, however, in the embodiment of FIGS. 6 and 7, water is caused to reside in the tank at the location previously occupied by the deadstock. Although there is normally a certain amount of water residing in the bottom of a bulk storage tank, the invention teaches to increase the amount of water substantially with the water 100 contained behind a coffer dam 102 so arranged at the inlet of delivery line 104 as to keep the delivery line free of water and filled with oil. The level of water is monitored by a sight glass 106 and controlled to be below the height of the coffer dam 102 by periodic drainage through the existing water draw off line 108. Since over a period of time, small amounts of entrained water may settle out in the suction well around delivery line 104, the suction well defined by coffer dam 102 is also provided with a small water draw off line 110, in addition to the main water draw off line 108. A similar coffer dam 114 relative to the intake line 116 is provided, however, this coffer dam 114 can be eliminated by repositioning the oil inlet line 116 to a higher level. The level of water 100 can be adjusted by periodically drawing off water through drawoff line 108.
The above-described embodiments of the invention all serve to reduce undrawable bottoms by adding elements to the inside of a tank, however, in another embodiment of the invention, the amount of deadstock in a tank is reduced by means attached only to the outside of a tank. The present invention contemplates replacing the conventional round suction nozzle used in bulk storage tanks with an elliptical or rectangular nozzle or with several smaller nozzles with a view to reducing the thickness of the layer of oil required to keep the suction line primed and full of oil. The dimensional relationships of the new nozzles are represented in 8A, 8B, 8C, and 9.
As set forth above, a primary determinant of the amount of undrawable bottoms in a bulk storage tank is the diameter of the suction nozzle. The lowest level to which the oil may be drawn is the top edge of the suction nozzle, since going below this line will permit the pump to suck air or other vapors and to become vapor locked. Because many delivery lines or suction lines are frequently as large as one to three feet in diameter, it is evident that a large layer of oil must reside in the tank as deadstock.
The invention reduces this volume of deadstock by lowering the topmost level of the suction nozzle. In one aspect of the invention, this can be done by providing an elliptical or rectangular suction nozzle of a size to provide the same cross-sectional area as the standard round suction nozzle. This relationship is easily demonstrated by the dimensions of the various sized nozzles. For instance, FIG. 8A represents a standard round nozzle of radius r, while FIG. 8b represents a flattened nozzle having the same cross-sectional area as the nozzle of FIG. 8C. FIG. 8C is a still flatter suction nozzle but still having a cross-sectional area equal to the other nozzles. Note that in both nozzles of FIGS. 8B and 8C the uppermost edge of the nozzle is lower than or below the upper edge of the standard round suction nozzle of FIG. 8A, thus permitting a reduction in the volume of oil held as deadstock. As another alternative, the conventional round suction line can be replaced by four smaller suction nozzles having a diameter r that is equal to the radius r of the original suction nozzle. The bottom edge of these four replacement nozzles would be at a line defined by the botton edge of the original round suction nozzle, thus reducing by 50% the thickness of the layer required to fill the suction nozzle and thereby the volume of oil held as deadstock. Other variations in sizes are of course possible, with multiple nozzles of the smallest possible size providing the maximum reduction in deadstock.
In still another emodiment, the existing round suction nozzle 120 of FIG. 9 is retained, but the upper half of the nozzle is blocked off, as represented by the shaded area 122. This has the effect of permitting the oil in the tank to be at a lower level before there is a danager of vapor-locking the pump. The area lost by block 122 is made up by two additional nozzles 124 and 125, again located with their bottom edge aligned with the bottom edge of main suction nozzle 120.
The suction nozzles of FIG. 9 can be installed in new tanks or they can be retrofitted on existing tanks. Such retrofitting can be accomplished while the tank remains in service using the hot-tapping procedures, known to those with skill in the petroleum storage field. Thus, the inventive nozzles can be hot-tapped to existing tanks and connected to existing suction lines and the existing nozzle sealed off either partially or fully at the tank. A manifold or header (not shown) can be used to combine the multiple nozzles for connection to the existing suction line.
The above description relates to various preferred embodiments of the present invention, however, it will be apparent that many other modifications and variations can be effected by one skilled in the art without departing from the spirit and scope of the novel concepts of the present invention, wherein the scope of the invention may be determined only by the appended claims.
For example, in regard to the modifications to the oil delivery nozzles, as an alternative to providing repositioned nozzles of smaller cross section the same result may also be achieved by extending the existing suction nozzle inwardly and swaging it down, so as to similarly lower the level at which the suction takes place. | A positive-displacement mass is introduced at the lowermost portion of an oil storage tank in order to reduce the amount of undrawable oil that remains at all times below the top edge of the suction line. It is necessary that the suction line not be occluded or interfered with and that the settled water at the bottom of the tank be permitted to be drawn off. In one aspect a tray is fitted into the bottom area of the tank and filled with water, or with inert solids, to displace the oil normally held as inventory at such location. In another aspect, a coffer dam is arranged around the suction line to permit the accumulation of water in the tank bottom, and in yet another aspect the shape and placement of the suction line nozzles are altered to improve storage efficiency. | 8 |
BACKGROUND OF THE INVENTION
[0001] CMOS-based (complementary metal-oxide-semiconductor) digital logic IC (integrated circuit) technologies have been devised over the last several years which operate at progressively lower power supply voltages with each passing design generation. Lower supply voltages dictate lower voltage swings for the associated digital signals, which typically traverse between ground and the power supply voltage. The benefits of using lower supply voltages are lower power consumption and faster signal switching times. CMOS logic IC power supply voltages currently available include, for example, 3.3 volts (V), 2.5 V, 1.8 V, and 1.5 V. Due to the multitude of IC technologies available, a mix of these technologies may be used in any particular electronic product.
[0002] One consequence of this mixing of technologies is that a digital signal with a relatively high voltage swing, such as a signal switching between 0 and 3.3 V, may have to be driven either off-chip or on-chip via input/output (I/O) pads using IC technology designed for lower voltages swings, such as from 0 to 2.5 V. Typically, for economic considerations, a single IC technology is utilized for the I/O pads of an IC. As lower voltage IC technology, such as 2.5 V circuitry, generally provides higher performance than that associated with higher voltages, such as 3.3 V, lower voltage IC technology is normally selected for all I/O pads of an IC. Therefore, the desirable solution in most cases is to employ low-voltage IC technology for all I/O signals, no matter what voltage range they traverse.
[0003] [0003]FIG. 1 shows a standard digital signal driver circuit 1 , consisting of a pair of complementary MOS FETs (Field Effect Transistors) structured as a CMOS inverter. A PFET (p-channel FET) P 1 and an NFET (n-channel FET) N 1 are connected in series between a power supply voltage V DD and a ground reference. The gate terminals of P 1 and N 1 are connected together and driven by an input signal V IN . The source terminal of P 1 and the drain terminal of N 1 are connected together to drive an output signal V OUT .
[0004] [0004]FIG. 2 graphically shows the operation of the standard driver circuit 1 . As V IN rises from LOW logic state at about zero volts up to a HIGH logic state of essentially V DD volts, P 1 turns OFF and N 1 turns ON, thereby driving V OUT from about V DD volts down to near zero volts. Oppositely, when V IN then returns from its HIGH state down to its low voltage level, P 1 returns to its ON state, N 1 shuts off, thereby driving V OUT up close to V DD volts.
[0005] Therefore, each of the FETs P 1 and N 1 must be able to handle drain-to-source voltages of approximately V DD volts. Unfortunately, in the case of a V DD power supply voltage of approximately 3.3 V, IC technology that is designed to support a V DD of 2.5 V cannot reliably handle such significantly higher power supply and digital signal voltages. For example, assume the standard driver circuit 1 was manufactured using 2.5 V technology. If a V DD of 3.3 V is employed to support input is and output signals switching between zero and 3.3 V, P 1 and N 1 , each will periodically have about 3.3 V across their drain-to-source junctions. As P 1 and N 1 are designed for 2.5 V operation, the overvoltage across each FET is likely to cause their eventual breakdown, resulting in the ultimate failure of the standard driver circuit 1 . Additionally, the extensive voltage swing in the input signal V IN periodically places 3.3 V across the gate-to-source junctions of both P 1 and N 1 , which also are only designed to handle 2.5 V. This gate-to-source overvoltage promotes breakdown of the FET gate oxide, causing even more permanent damage to the FETs involved.
[0006] Alternately, as displayed in FIG. 3, small linearizing resistors R P and R N may be connected in series with P 1 and N 1 , respectively, resulting in a modified driver circuit 2 . Although any current passing through the resistors R P and R N will cause a small portion of the high voltage power supply V DD to appear across the resistors, the voltage across each of the FETs P 1 and N 1 is likely to still be too high to guarantee proper operation of the modified driver circuit 2 .
[0007] From the foregoing, a need exists for a driver circuit that drives digital signals and utilizes a power supply voltage that both exhibit higher voltage levels than those for which the associated IC technology was designed. Such a driver circuit would operate under those high voltage conditions without suffering significant voltage breakdown or other reliability problems.
SUMMARY OF THE INVENTION
[0008] Embodiments of the invention, to be discussed in detail below, utilize PFETs and NFETs that clip the voltage present across both the drain-to-source and gate-to-source junctions of a driving PFET and driving NFET of the driver circuit. The clipping PFETs and NFETs ensure that the drain-to-source and gate-to-source voltages of all of the FETs of the driver circuit are within the voltage design limits of the associated IC technology when the imposed power supply and digital signal voltages are substantially higher than those for which the associated IC technology was designed.
[0009] Other aspects and advantages of the invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, illustrating by way of example the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] [0010]FIG. 1 is a schematic diagram of a standard digital signal driver circuit from the prior art.
[0011] [0011]FIG. 2 is an idealized voltage vs. time graph describing the operation of the standard digital signal driver circuit of FIG. 1.
[0012] [0012]FIG. 3 is a schematic diagram of a modified driver circuit from the prior art.
[0013] [0013]FIG. 4 is a schematic diagram of a digital signal driver circuit according to an embodiment of the invention.
[0014] [0014]FIG. 5A and FIG. 5B are schematic diagrams of two alternative active voltage dividers that generate bias voltages for the digital signal driver circuit of FIG. 4.
[0015] [0015]FIG. 6 is an idealized voltage vs. time graph describing the operation of the digital signal driver circuit of FIG. 4.
[0016] [0016]FIG. 7 is a schematic diagram of a second digital signal driver circuit according to an embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0017] One embodiment of the invention, an enhanced digital signal driver circuit 100 , is displayed in FIG. 4. A p-channel FET P DRIVE and an n-channel FET N DRIVE are employed to drive an output signal V OUT to a logic HIGH or LOW, depending on the voltage level of an input signal V IN . In the case of FIG. 4, a logic HIGH for either V IN or V OUT corresponds with a high voltage power supply V DDH , and a logic LOW is essentially at a ground reference point. Assuming that the enhanced driver circuit 100 is implemented using technology suited for lower power supply voltages, the presence of voltage of the magnitude of V DDH would cause reliability problems within the enhanced driver circuit 100 without the surrounding circuitry shown. For example, if V DDH were approximately 3.3 V, and the circuit used to implement the enhanced driver circuit 100 were designed for 2.5 V operation, the presence of 3.3 V across the drain-to-source junction or the gate-source junction of either P DRIVE or N DRIVE would likely cause reliability problems, and possibly permanent damage, to those FETs, as described above in relation to the prior art standard driver circuits 1 and 2 .
[0018] To alleviate this problem, the enhanced driver circuit 100 includes additional circuitry that “clips,” or reduces, the voltage imposed on the driving FETs P DRIVE and N DRIVE . With respect to P DRIVE , a PFET P CLIP1 is positioned in series with P DRIVE between the source of P DRIVE and the output signal V OUT . P CLIP1 clips the voltage across the drain-to-source junction of P DRIVE by sharing part of the high voltage power supply level V DDH that will exist across P DRIVE and P CLIP1 whenever V OUT is driven LOW, close to the ground voltage reference. With each of P DRIVE and P CLIP1 sharing a portion of V DDH , both of those two FETs will be operating within their voltage design limits, thus eliminating the reliability concerns associated with older driver circuits.
[0019] A second P FET , P CLIP2 , addresses the problem of potentially excessive voltage across the gate-to-source junction of P DRIVE by sharing that voltage with P DRIVE . For example, with V IN at a logic LOW level, V OUT will be driven HIGH, thus causing both the source and drain of P DRIVE to reside at or near V DDH volts. If V IN were to be asserted directly at the gate of P DRIVE , the gate-to-source (and gate-to-drain) junction of P DRIVE would have to handle the full magnitude of V DDH , potentially causing gate oxide breakdown of P DRIVE , as described above. However, with P CLIP2 residing between the input signal V IN and the gate of P DRIVE , the possibility for V DDH volts to be impressed across the gate-to-source (or gate-to-drain) junction of P DRIVE is eliminated due to P CLIP2 accepting part of that voltage.
[0020] Concerning the bottom portion of the enhanced driver circuit 100 , as depicted in FIG. 4, the driving FET N DRIVE is similarly protected by way of a pair of clipping NFETs, N CLIP1 and N CLIP2 . These clipping NFETs work in a fashion analogous to the clipping PFETs P CLIP1 and P CLIP2 , described above. The drain-to-source junction of N DRIVE is protected by the use of N CLIP1 between the drain of N DRIVE and the output signal V OUT during those times when V OUT is at a logic HIGH level as a result of V IN being forced toward the ground reference voltage. Similarly, N CLIP2 , which is positioned between the input signal V IN and the gate of N DRIVE , protects N DRIVE from gate oxide breakdown by limiting the voltage across the gate-to-source (and gate-to-drain) junction of N DRIVE when V IN is at the logic HIGH state, at about V DDH volts.
[0021] To ensure that the clipping FETs operate properly, the gate of each of the clipping FETs is biased at a voltage level which prevents each clipping FET from operating in saturation during those times when the FET is required to clip the voltage across a junction of the associated driving FET. For example, the gates of P CLIP1 , and P CLIP2 are tied to a voltage V LBIAS , which resides at an intermediate value between V DDH /2 and the ground reference voltage. Likewise, the gates of N CLIP1 and N CLIP2 have a voltage V HBIAS forced thereupon at an intermediate value between V DDH and V DDH /2.
[0022] In the specific example of FIG. 5A, V HBIAS and V LBIAS are generated by way of an active voltage divider 200 formed from a set of four stacked PFETS P B1 , P B2 , P B3 and P B4 connected in series between V DDH and ground. Each of the stacked PFETs is essentially in the OFF state, as the gate and source of each stacked PFET are connected together. As a result of the stacked configuration, V HBIAS maintains a voltage of approximately 3V DDH /4, while V LBIAS resides at about V DDH /4. Optionally, other circuits providing similar bias voltages may also be employed. In addition, low bias voltage V LBIAS and high bias voltage V HBIAS each may be coupled to the ground voltage reference via capacitors C H and C L to stabilize their voltage levels. These capacitors may be of substantial capacity (on the order of a microfarad, for example), especially if one such active voltage divider 200 is employed to service several enhanced driver circuits 100 .
[0023] [0023]FIG. 5B displays an alternate active voltage divider 250 that uses four stacked NFETs N B1 , N B2 , N B3 and N B4 , with the gate of each NFET connected to the drain of that same NFET. The alternate active voltage divider 250 generates essentially the same values for V HBIAS and V LBIAS as those associated with the active voltage divider 200 of FIG. 5A.
[0024] The effects of the clipping FETs, as biased by the high and low bias voltages, can be seen in the waveform diagrams of FIG. 6, while referencing the enhanced driver circuit 100 of FIG. 4. As V IN proceeds from a logic LOW level to a logic HIGH of about V DDH volts, the drain of N CLIP2 rises to that level. With V HBIAS driving the gate of N CLIP2 to some voltage less than V DDH to prevent saturation of N CLIP2 (3V DDH /4, in this case), N CLIP2 develops a significant voltage across its drain-to-source junction, thereby allowing the voltage at the gate of N DRIVE (indicated by the reference point V NCLIP2 ) to rise to some level significantly less than V DDH while still allowing the gate of N DRIVE to be driven high enough to turn ON N DRIVE . This action aids in pulling the drain of N DRIVE and the source of N CLIP1 (indicated by the reference point V NCLIP1 ) toward ground. With the gate of N CLIP1 biased at V HBIAS , N CLIP1 is turned ON as well, pulling the output signal V OUT approximately to the ground reference voltage.
[0025] As V OUT is pulled LOW, thus pulling the source of P CLIP1 along with it, P CLIP1 tends toward the OFF state since the gate of P CLIP1 is held at the voltage level V LBIAS . At the same time, with V IN causing a HIGH logic level at the drain of P CLIP2 , and the gate of P CLIP2 being held at the low bias voltage V LBIAS , P CLIP2 is essentially ON, thereby forcing the gate of P DRIVE to a logic HIGH. Hence, P DRIVE is turned OFF as well, causing the drain of P CLIP1 (indicated by the reference point V PCLIP1 ) to reside at a voltage near the midpoint between V DDH and ground, at which V OUT is driven.
[0026] In the case that V IN then is driven toward the ground reference voltage, the drain of P CLIP2 is pulled to ground as well. With the gate of P CLIP2 being held at V LBIAS (in this case, V DDH /4), P CLIP2 conducts at less than the saturation level, causing a significant voltage drop across the drain-to-source junction of P CLIP2 . As a result, the voltage at the gate of P DRIVE (i.e., V PCLIP2 ), drops to an intermediate voltage between V DDH and ground which is low enough to turn ON P DRIVE , which, in turn, causes the source of P DRIVE and the drain of P CLIP1 (denoted by V PCLIP1 ) to raise essentially to V DDH . With the gate of P CLIP1 , being maintained at V LBIAS , P CLIP1 is turned ON as well, causing V OUT to rise essentially to V DDH .
[0027] With V OUT being pulled HIGH, along with the drain of N CLIP1 , N CLIP1 tends toward the OFF state because of the gate of N CLIP1 being held at V HBIAS . At the same time, the LOW logic level of V IN is forced upon the drain of N CLIP2 , thus causing N CLIP2 to be essentially turned ON, ensuring the source of N CLIP2 and the gate of N DRIVE (i.e. V NCLIP2 ) are brought down to essentially ground. N DRIVE is thus essentially OFF, along with N CLIP1 . In that state, the drain of N DRIVE and the source of N CLIP1 (indicated by V NCLIP1 ) reside at an intermediate voltage between V DDH and ground.
[0028] Thus, whether V IN attains the logic HIGH level (at about V DDH volts) or the logic LOW level (at about ground), none of the FETs of the enhanced driver circuit 100 sustain a voltage beyond which the FETs can safely handle. The maximum voltage across any FET will be in the neighborhood of V DDH /2, depending on the physical characteristics of the FETs and the actual voltage levels of V HBIAS and V LBIAS . As a result, the FETs should be implemented using an IC technology that can handle voltages of about V DDH /2 in order to prevent any damage or reliability problems due to overvoltage. For example, assuming IC technology of 2.5 volts is employed for the enhanced driver circuit 100 , a V DDH of 3.3 V, as well as input and output signal voltage swings between ground and 3.3 V, are handled effectively. However, power supply and signal voltage levels well in excess of 5 V would not be applicable to the use of 2.5 V IC technology.
[0029] Other embodiments based upon the enhanced driver circuit 100 may also be employed in accordance with the present invention. For example, FIG. 7 shows a second enhanced driver circuit 300 comprising the FETs of the enhanced driver circuit 100 of FIG. 4 with a couple of additional linearizing resistors R P and R N connected in series with P CLIP1 and N CLIP1 . The junction of R P and R N form the signal output V OUT . Other modifications of the enhanced driver circuit 100 may also be employed in accordance with the inventive concepts described herein.
[0030] Due to the additional FETs employed in enhanced driver circuit 100 over that required for the standard driver circuit 1 , the total amount of capacitance of the enhanced driver circuit 100 that is charged and discharged when the input signal V IN changes logic states causes the enhanced driver circuit 100 to operate more slowly in most cases than the standard driver circuit 1 of similar IC technology. As a result, embodiments of the present invention are particularly well-suited for applications that value small circuit footprint and design flexibility over the highest possible circuit switching speeds. For example, many system interface bus implementations, such as Peripheral Component Interconnect X (PCIX), a popular 64-bit computer bus architecture capable of running at bus speeds of up to 133 Megahertz (MHz), would benefit from employment of embodiments of the invention. Other systems requiring similar performance characteristics could particularly benefit the use of such driver circuits.
[0031] From the foregoing, the invention provides a simple digital signal driver circuit capable of driving high-voltage digital signals using comparatively low-voltage IC technology while eliminating the circuit damage and operational reliability problems exhibited by other driver circuits. Embodiments other than those shown above are also possible. As a result, the invention is not to be limited to the specific forms and arrangements of components so described and illustrated; the invention is limited only by the claims. | An enhanced digital signal driver circuit that allows the driving of digital signals with a larger voltage swing than that which is typically allowed by the associated IC technology is provided. The driver circuit employs PFETs and NFETs that clip the voltage present across both the drain-to-source and gate-to-source junctions of a driving PFET and a driving NFET of the driver circuit. The clipping PFETs and NFETs ensure that the drain-to-source and gate-to-source voltages of all of the FETs of the driver circuit are within the voltage design limits of the associated IC technology when the imposed power supply and digital signal voltages are substantially higher than those for which the associated IC technology was designed. | 7 |
This application is a continuation of application Ser. No. 043,909, filed May 30, 1979, now abandoned.
BACKGROUND OF THE INVENTION
This invention relates to portable hair dryers used in close proximity to the user's hair. More specifically, this invention relates to axial fan driven portable hair dryers with means for preventing hair entanglement of the user when the hair dryer is used in close proximity with the hair, such as during a styling or drying maneuver.
In the past, most electrically heated forced-air hair dryers included a transverse flow fan when used with styling attachments such as a comb or a brush. Axial fan hair dryers when used with attachments were typically bulky in nature and inconvenient to use.
If a more compact design of a portable axial fan hair dryer with or without attachments was desirable, a problem resulted in that the working end would be within a few inches of the axial fan. This may result in hair entanglement through the air inlet of the hair dryer.
The prevention of hair entanglement through the air inlet may be somewhat helped by including a mesh screen over the air inlet. However, the mesh may not be too fine since it will cause lint or the like to clog up the air inlet screen and thus restrict air flow causing the unit to overheat.
When a compact hair dryer, with a relatively short air flow portion, is used with or without styling implements, the hair of the user may readily enter through the air inlet portion of the hair dryer either when still attached to the user's head or as separate pieces of hair. The aerodynamics of the hair dryer system and the presenting of the center of rotation of the axial fan very proximate the air inlet is believed to create hair entanglement problems more serious than those associated with a transverse flow hair dryer used with styling attachments.
There are two basic types of hair entanglement problems which will effect the operation of the hair dryer and/or the safety or ease of use of the hair dryer. The first type deals with hair entanglement when the hair remains attached to the user's head. If hair enters through the air inlet portion of the hair dryer, the hair strands may engage the fan shaft or its associated bearing and result in the fan stalling. Such an entanglement may cause the user to be pulled toward the dryer, and if the fan stalls, a situation may momentarily exist where the user is attached to the hair dryer and the heat of the hair dryer is increasing.
Another hair entanglement problem occurs when hair strands of the user enter through the air inlet in front of the fan. Because the center of rotation of the axial fan faces the air inlet, the hair strands tend to find the center of the system and start to twist. If such a twisting occurs among several strands, the hair may become twisted together and form a knot inside the screen thus causing the user to either pull free or cut the entangled hair.
Further problems result when loose hair falls into the air inlet portion through the screen. These loose hairs may eventually wrap around the shaft beneath the fan until they fill up whatever space is available. When the loose hair builds up, the fan may slow down and cause an associated thermostat to open which ultimately may result in consumer dissatisfaction and excessive returns.
These prior art difficulties have been substantially overcome by providing a compact axial fan hair dryer suitable for use as a dryer or styler in close proximity to the hair. The hair dryer includes a stationary guard or shield assembly in the air inlet portion of the hair dryer and a collar affixed to the downstream portion of the fan blades and disposed about the motor.
SUMMARY OF THE INVENTION
It is an object of this invention to provide an axial fan hair dryer which may be used in a safe and convenient manner in close proximity to the hair.
It is another object of this invention to provide a compact axial fan hair dryer which substantially prevents hair knotting and tangling problems.
It is a further object of this invention to provide an axial fan compact hair dryer which may be used with a plurality of styling attachments which includes means for substantially preventing hair entanglement of the user without unreasonably interfering with the air flow dynamics of the system.
Briefly stated, and according to an aspect of this invention, an axial fan hair dryer is provided which substantially prevents hair entanglement problems by means of a stationary shield and a rotating collar without detrimentally affecting the air flow characteristics of the system.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention both as to its organization and principles of operation, together with further objects and advantages thereof, may better be understood by referring to the following detailed description of an embodiment of the invention taken in conjunction with the accompanying drawings in which:
FIG. 1 is a perspective view of a compact axial fan hair dryer and an associated styling attachment, in accordance with this invention.
FIG. 2 is a cross-sectional top view of the air flow portion of the hair dryer of FIG. 1, in accordance with this invention.
FIG. 3 is an end view, partial in section, of the air inlet of the air flow portion of the hair dryer of FIG. 1, in accordance with this invention.
DETAILED DESCRIPTION
Referring now to FIG. 1, the hair dryer includes a dryer housing 10 which is preferably made of plastic and comprises separate mating sections 11 and 12. The sections 11 and 12 are connected together by means of snap locks located along their respective periphery and also by means of screws (not shown) or the like. The housing 10 includes handle portion 13 which is generally cylindrical or eliptical in cross section to provide a comfortable grip for the user, and an air flow portion 14.
The handle portion 13 provides an aperture for access to an on/off switch 15. The on/off switch 15 is electrically connected to an AC line cord 16 extending from the bottom of the handle portion 13 in the manner well known in the art. Other types of control circuitry which provide a variety of fan speed/heating settings, as well as a dual voltage capability, may be provided in a manner well known in the art.
The upper part of the handle portion 13 is integrally molded at about the mid-point of the air flow portion 14 to provide for a balanced easy-to-manipulate hair dryer 10. The air flow portion 14, which may be approximately three inches in length, defines an air inlet 17 and an air exhaust or outlet 18. Preferably the air inlet 17 is generally circular in shape and the air flow portion 14 gradually forms an air outlet 18 of a generally rectangular cross section. The generally rectangular cross section of air outlet 18 includes shorter upper and lower parallel sides which each include an integrally molded stud or post such as posts 19 and 20 to be used with snap-on attachments, in a manner well known in the art.
Attachment 21, which includes a styling portion 22 such as a comb or brush, has upper and lower plastic resilient arms 23 and 24. Apertures 25 and 26 are defined respectively in upper and lower arms 23 and 24 to provide a snap fit over posts 19 and 20, all in a manner well known in the art. Other types of mounting arrangements for styling attachments are suitable when the hair dryer is to be used for styling the hair.
Referring now to FIGS. 2 and 3 of the drawings, air is drawn in through the air inlet 17 of the air flow portion 14 through a wire mesh screen 27. The screen 27 is interlocked at its generally circular periphery into the cabinet sections 11 and 12 in a manner well known in the art. Disposed downstream from the screen 27 is a screen support 28 best seen when referring to FIG. 3. The screen support 28 is made up of a piece of metal, plastic or the like preferably in a generally cross configuration and of minimum size in order to block as little of the air passageway as possible. The crosslike screen support 28 is bowed out toward the screen 27 to provide structural rigidity to the screen 27. The center point of the support 28 defines an aperture 29 through which a securing member such as screw 30 fixes a guard or shield 31 to the support 28. The screen support 28 may be interlocked into the sections 11 and 12 of housing 10 or otherwise affixed thereto in any manner well known in the art.
The guard or shield 31 may be made of a plastic and is generally dome shaped. The shield 31 is connected to the screen support 28 through its integrally molded threaded mounting post 32. The shield 31 is positioned such that it provides proper clearance to the fan blades 33 and fan hub 34. The smooth downstream outer surface of the shield 31 provides minimum air flow restriction. The shield 31 is fixed only to the center portion of the screen support 28 to minimize air flow restriction problems and also to substantially prevent the knotting problem previously described. That is, if loose hair gets through the screen 27, it tends to collect or wind about the mounting post 32. The resulting hair causes little air flow restriction and does not detrimentally affect the operation or safety of the hair dryer.
Further, when hair connected to the user finds its way through the screen 28 onto the outer surface of the shield 31, the aerodynamic forces that are present still cause the hair to migrate toward the center of the system. However, because the shield 31 is present, the user's hair tends to lay across the outer surface of the shield 31. Since the hub is not spinning, the hair tends not to get knotted. Thus, when the dryer is moved away from the hair, the hair strands in the dryer laying on the surface of the shield 31 will tend to ease readily through the mesh of the screen 27.
Disposed within the upstream inner surface of the dome shaped shield 31 is a brass bushing 35 which, in a manner well known in the art, mounts the fan 33 with its hub 34 to the motor shaft 36. The fan 33 is a stamped aluminum fan having a plurality of blades 33, such as four in number, all joined by means of the generally circular fan hub 34. The fan hub 34 has a centrally defined aperture through which the motor shaft 36 is disposed.
Between the upstream portion of the motor 37 in the bushing 35 and the downstream side of the fan hub 34 and connected to the downstream portion of the fan blades 33 is a rotating collar 38. The collar 38 which may be integrally formed of plastic or formed as a stamped metal piece with the fan assembly (fan 33 and fan hub 34) is generally cylindrical in shape and comprises a wall portion 39, concentrically disposed about part of a motor mount 44, and a top portion 40. The top portion 40 is, of course, generally circular and defines a central aperture for receiving the motor shaft 36 and motor bearing 42. The length of the wall portion 39 of the collar 38 is preferably long enough to extend beyond the most downstream portion of the fan blades 33 such as extended portion 41. The extended portion 41 of the collar 38 beyond the fan blades 33 is believed to aid in the prevention of hair entanglement problems previously described.
In general, the collar 38 on its upstream surface is affixed to fan blades 33 and bushing 35 and accordingly rotates in unison with the fan blades 33 about the motor axis 36. The collar 38 substantially prevents hair connected to the user from wrapping around the motor shaft 36 on the downstream side of bushing 35 and pulling the user toward the hair dryer. In addition, the collar 38 substantially prevents loose hairs from being disposed about the motor shaft 36 and interfering with the normal operation of the system and causing premature breakdown and customer dissatisfaction.
The motor 37 is capable of driving the associated fan assembly, made up of blades 33 and fan hub 34, and collar 38 at about 15,000 to 18,000 rpm. The motor 37 is a DC permanent magnet motor such as that manufactured by Mabuchi in Japan as Model RS-365. However, it is understood that the choice of a motor is not critical in practicing this invention.
If desired, in order to take the spin out of the air flow, a fixed vane assembly is provided. Although not necessary for the practice of this invention, the fixed vane assembly provides a more efficient hair dryer system. In general, the fixed vane assembly may be formed of a plastic such as polycarbonate and comprises an integrally formed generally cylindrical shroud 43 disposed about the outside of the fan/motor assembly and a generally cylindrical motor mount 44 disposed about an upstream portion of motor 37. The inner surface of the shroud 43 and the outer surface of the motor mount 44 are interconnected through a plurality of air foils or fixed vanes 45, such as nine in number, all in a manner well known in the art. The shroud 43 may extend about the fan blades 33 and also about the fixed vanes 45 located downstream from the fan blades 33.
Located downstream from the fixed vane assembly are concentrically wound iron chrome resistance wire heater coils 46 disposed in the downstream portion of the air flow portion 14 and partially disposed about the motor 37. The coils 46 are mounted in appropriate slots of Micaboards 47 and 48 in a manner well known in the art. The Micaboards 47 and 48 in turn are connected to the inner walls of sections 11 and 12 of housing 10.
An air exhaust grill 49 is disposed over the air exit or outlet 18 and is interconnected to sections 11 and 12 of housing 10 and Micaboards 47 and 48 through interlocks or the like.
While an embodiment and application of the invention has been shown and described, it will be apparent to those skilled in the art that many more modifications are possible without departing from the inventive concepts herein described. The invention, therefore, is not to be restricted except as is necessary by the prior art and by the spirit of the appended claims. | A hand-held portable axial fan hair dryer having an air inlet and an air outlet is provided with a shield and collar assembly proximate the air inlet to substantially prevent hair knotting and tangling. Hair styling attachments, such as a comb or brush, may be removably attached proximate the air outlet. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation application of application Ser. No. 09/368,034, filed Aug. 3, 1999, now U.S. Pat. No. 6,479,706 which is a continuation-in-part application of application Ser. No. 09/017,852, filed Feb. 3, 1998, now abandoned, which is related to commonly owned Provisional Application Ser. No. 60/037,155, filed Feb. 4, 1997. This application is also related to pending application Ser. No. 08/858,268, filed May 19, 1997, which is related to commonly owned Provisional Application Ser. No. 60/017,127, filed May 20, 1996. All of the above-described applications are incorporated in their entirety by reference.
FIELD OF THE INVENTION
This invention relates generally to novel photoactive compounds and methods for using the same. More particularly, this invention relates to aminobenzophenones and methods of using the same in photoactivatable polymerization systems.
BACKGROUND OF THE INVENTION
Ethylenically unsaturated compounds, and in particular acrylate derivatives, can be polymerized by irradiation with ultraviolet light of wavelength between 200 and 450 nanometers (nm) in the presence of a bimolecular photoinitiating system. The photoinitiating system can include, for example, (1) a benzophenone derivative and (2) a coinitiator or synergist, that is, a molecule which serves as a hydrogen atom donor. The coinitiators or synergists are typically alcohols, tertiary amines or ethers which have available hydrogens attached to a carbon adjacent to a heteroatom.
One commercially available benzophenone derivative useful as a photoinitiator is 4,4′-bis(dimethylamino)benzophenone, also referred to in the art as “Michler's Ketone”. Michler's Ketone has the following structure:
While Michler's Ketone can be useful as a photoinitiator in radiation curing of polymers, it is typically used little in the industry due to its potentially hazardous characteristics.
4,4′-Bis(diethylamino)benzophenone (also referred to as tetraethyl Michler's Ketone) has been proposed as a possible alternative to Michler's Ketone due to its lower toxicity. However, this compound does not exhibit good photoinitiating activity and thus has not been widely adopted as an alternative to Michler's Ketone.
Other Michler's Ketone derivatives are described, for example, in U.S. Pat. No. 4,507,497 to Reilly, Jr., which is directed to water soluble Michler's Ketone analogs which include amino groups substituted by R 1 COOH, in which R 1 is an alkylene group having 1 to 8 carbon atoms.
Examples of other commercially available photoinitiators useful in bimolecular photoinitiator systems include benzophenone, 2,4-dimethylbenzophenone, isopropylthioxanthone, and 2,4-diethylthioxanthone. The UV absorption spectrum for these individual photoinitiators, however, do not match-up efficiently with the UV emission spectra of the standard commercially available mercury vapor bulbs.
Thus, commercially viable UV curing processes can require a relatively large amount of initiator and synergist incorporated into the formulation. This can lead to cured articles which contain high levels of residual photoinitiator and synergist, which in turn can result in decreased light fastness and lower resistance to oxidative degradation. In addition, the residual photoinitiator and synergist can be extracted or leach out of the cured article or migrate to the surface of the article. Many times the physical properties of the article are degraded by the presence of the residual photoinitiator and synergist.
SUMMARY OF THE INVENTION
It is accordingly an object of the present invention to provide compounds which can be used as photoinitiators in photopolymerization processes. It is also an object of the invention to provide compounds which exhibit useful photoinitiation activity with minimal or no adverse hazardous characteristics. These and other objects of the present invention will become apparent from the following general and detailed description of the invention.
The objects of the present invention are achieved based on the discovery of novel compounds useful in photopolymerization systems. The compounds can display highly active photoinitiation and photopolymerization properties with minimal or no adverse hazardous characteristics. Specifically the compounds can be essentially or substantially non-mutagenic. As is well known in the art, photoinitiator that is not consumed in the photopolymerization reaction may be extracted or leached from the cured product. Therefore a non-mutagenic photoinitiator is especially desirable.
Still further, the compounds can have desirable ultraviolet wavelength absorbance, which in turn can provide advantages when using narrow wavelength lamps. In this regard, advantageously the compounds possess UV spectra with significant absorption bands between 250 and 350 nm and in particular between 290 and 325 nm. Accordingly, the compounds can be irradiated with a narrow wavelength band, high pressure fill UV curing lamp known as an excimer lamp with spectral emphasis in the 250 to 350 nm range, and in particular with its peak emission wavelength at or near 308 nm, as described in U.S. Pat. No. 5,504,391.
Compounds showing a significantly elevated level of reactivity at these wavelengths can be used in considerably lower amounts. For example, when the compounds of the invention are used with an excimer lamp versus a medium pressure mercury lamp, only about one-fourth of the amount of photoinitiator can be required to give equivalent cure speeds. In addition, when the same concentration of photoinitiator is used with both an excimer and a medium pressure mercury lamp the excimer lamp can provide greatly increased cure speeds. Because less photoinitiator is required, less residual photoinitiator can remain in the cured articles, thereby minimizing problems associated with leaching or extraction, decreased light fastness and lower resistance to oxidative degradation.
The compounds of the invention have a structure according to Formula (I) below:
wherein:
each A is independently selected from the group consisting of hydrogen, lower alkyl, cycloalkyl, aryl, lower alkanol, lower alkoxy, halogen, sulfonyl, alkylsulfonyl, trihaloalkyl, trihaloalkoxy, trihaloalkylthio, polymerizable moiety, and oligomeric moiety, with the proviso that no more than three A are the same lower alkyl;
each R is independently selected from the group consisting of hydrogen, lower alkyl, cycloalkyl, aryl, lower alkanol, lower alkoxy, halogen, sulfonyl, alkylsulfonyl, trihaloalkyl, trihaloalkoxy, trihaloalkylthio, polymerizable moiety, and oligomeric moiety; and
n is an integer from 1 to 4.
The present invention also provides photopolymerizable compositions which include the compounds of Formula (I) above as a component thereof, as well as methods for the manufacture of the compounds of Formula (I) and methods for the use of the compounds of Formula (I) in photopolymerization systems.
BRIEF DESCRIPTION OF THE DRAWINGS
Some of the features and advantages of the invention having been described, others will become apparent from the detailed description which follows, and from the accompanying drawings, in which:
FIG. 1 illustrates the ultraviolet (UV) emission spectrum of an excimer lamp as described in U.S. Pat. No. 5,504,391; and
FIG. 2 illustrates the UV absorption of 4,4′-bis(methylethylamino)benzophenone (MEAB).
DETAILED DESCRIPTION OF THE INVENTION
The novel compounds of the invention include compounds according to Formula (I) below:
wherein:
each A is independently selected from the group consisting of hydrogen, lower alkyl, cycloalkyl, aryl, lower alkanol, lower alkoxy, halogen, sulfonyl, alkylsulfonyl, trihaloalkyl, trihaloalkoxy, trihaloalkylthio, polymerizable moiety, and oligomeric moiety, with the proviso that no more than three A are the same lower alkyl;
each R is independently selected from the group consisting of hydrogen, lower alkyl, cycloalkyl, aryl, lower alkanol, lower alkoxy, halogen, sulfonyl, alkylsulfonyl, trihaloalkyl, trihaloalkoxy, trihaloalkylthio, polymerizable moiety, and oligomeric moiety; and
n is an integer from 1 to 4.
As used herein, the term lower alkyl refers to linear or branched C1-C8 alkyl, such as but not limited to methyl, ethyl, propyl, isopropyl, n-butyl, t-butyl, and the like, optionally substituted with one or more halogen, aryl, arylalkyl, alkylaryl, cycloalkyl, alkoxy, heteroatom, and the like. The term cycloalkyl refers to C3 to C6 cyclic alkyl, such as but not limited to cyclopropyl, cyclobutyl, cyclopentyl and cyclohexyl, optionally substituted with one or more halogen, aryl, alkyl, arylalkyl, alkylaryl, cycloalkyl, alkoxy, heteroatom, and the like. The term alkanol refers to lower alkyl substituted with one or more hydroxyl groups. The term lower alkoxy refers to lower alkyl substituted with one or more oxygen atoms, including but not limited to methoxy, ethoxy, propoxy, butoxy, and the like. The term alkylsulfonyl refers to lower alkyl substituted with sulfonyl. The terms trihaloalkyl, trihaloalkoxy, and trihaloalkylthio refer to lower alkyl, lower alkoxy and lower alkylthio, respectively, in which hydrogen atoms on the organic group are replaced with halogen, preferably fluorine. The term aryl refers to C3 to C10 cyclic aromatic groups such as but not limited to phenyl, naphthyl, and the like, optionally substituted with one or more halogen, alkyl, arylalkyl, alkylaryl, cycloalkyl, alkoxy, heteroatom, and the like. The term heteroatom refers to oxygen, nitrogen, sulfur or phosphorous.
The term polymerizable moiety refers to ethylenically unsaturated moieties known in the art which are capable of reaction with another compound (for example by a free radical mechanism), such as but not limited to, acrylate and methacrylate moieties. For example A can have the structure —(CH 2 ) n —OC(O)—CRH═CH 2 , wherein n is an integer from 1 to 10 and R is H or lower alkyl. Yet another exemplary polymerizable moiety can be a maleimide moiety
wherein:
R′ is selected from the group consisting of —(CH 2 ) n —, wherein n is an integer from 0 to 10, optionally substituted with one or more heteroatom in the —CH 2 — chain; and
each R″ is independently selected from the group consisting of hydrogen, lower alkyl and halogen.
The term oligomeric moiety refers to a moiety including two or more monomer units (dimer, trimer, etc.) such as but not limited to an C2C20 alkylene or polyalkylene polyol, wherein hydroxy groups of the polyol are optionally alkylated, and preferably an alkylene or polyalkylene polyol derived from ethylene glycol. Other suitable oligomer moieties include C2-C20 alkylene or polyalkylene moieties end capped with trihaloalkyl, and optionally substituted with one or more halogen atoms along the chain, preferably fluorine. Other exemplary oligomeric moieties include C2-C20 alkylene or polyalkylene moieties including carbonate groups and end capped with lower alkyl.
In one embodiment of the invention, each A of the compound of Formula (I) is lower alkyl, preferably methyl or ethyl, with the proviso that no more than three As are the same. In another embodiment of the invention at least one A is lower alkyl, preferably methyl or ethyl, and at least one other A is a polymerizable moiety or an oligomeric moiety.
Exemplary compounds in accordance with Formula I include without limitation:
wherein x is an integer from 1 to 20; and the like.
Advantageously the compounds of the invention, such as MEAB, are appropriately substituted to possess UV spectra with significant absorption bands between 250 and 350 nanometers (nm), more preferably between 290 and 325 nm, and most preferably about 308 nm.
In another embodiment of the invention, photopolymerizable compositions are provided which include a compound of Formula (I) above as a photoinitiator. As used herein, and as will be appreciated by the skilled artisan, the term photopolymerizable composition refers to compositions which harden or cure upon exposure to radiation.
Generally the compositions of the invention include ethylenically unsaturated compounds, including monomers, oligomers, polymers, prepolymers, resinous materials, optionally dispersed or dissolved in a suitable solvent that is copolymerizable therewith, and mixtures thereof, which are photopolymerizable when exposed to a source of ultraviolet (“UV”) radiation. As will be appreciated by the skilled artisan, the photopolymerizable compounds can be monofunctional, or can include two or more terminal polymerizable ethylenically unsaturated groupings per molecule.
Exemplary photopolymerizable compounds or precursors include, but are not limited to, reactive vinyl monomers, including acrylic monomers, such as acrylic and methacrylic acids, and their amides, esters, salts and corresponding nitriles. Suitable vinyl monomers include, but are not limited to, methyl acrylate, ethyl acrylate, n- or tert-butylacrylate, isooctyl acrylate, methyl methacrylate, ethylmethacrylate, 2-ethylhexyl methacrylate, butylacrylate, isobutyl methacrylate, the corresponding hydroxy acrylates, i.e., hydroxy ethylacrylate, hydroxy propylacrylate, hydroxy ethylhexyl methacrylate, glycol acrylates, i.e., ethylene glycol dimethacrylate, hexamethylene glycol dimethacrylate, the allyl acrylates, i.e., allyl methacrylate, diallyl methacrylate, the epoxy acrylates, i.e., glycidyl methacrylate, and the aminoplast acrylates, i.e., melamine acrylate. Others such as vinyl acetate, vinyl and vinylidene halides and amides, i.e., methacrylamide, acrylamide, diacetone acrylamide, butadiene, styrene, vinyl toluene, and the like are also included. Prepolymers include acrylated epoxides, polyesters and polyurethanes, and are typically combined with a suitable monomer for viscosity control. The photopolymerizable compounds may be polymerized to form homopolymers or copolymerized with various other monomers.
The photopolymerizable compound can be present in the compositions of the invention in amounts between about 99.8 and about 90 percent by weight of the composition, preferably between about 99.5 and about 95 percent by weight.
In this aspect of the invention, the compounds of Formula (I) act as photopolymerization initiators. The compounds of Formula (I) are added to the photopolymerizable compound in an amount sufficient to initiate polymerization thereof upon exposure to ultraviolet radiation. Preferably the compounds of Formula (I) are present in the photopolymerizable composition an amount between about 0.2 and 10 parts by weight of the composition, and more preferably between about 0.5 and about 5 parts by weight, depending on the specific application.
The use of the compounds of Formula (I) can exhibit photoinitiation activity similar to that of Michler's Ketone, but unexpectedly also have greatly reduced toxicity.
The compositions of the invention can also include any of the various pigments, organic and inorganic, known in the art. Exemplary pigments include, but are not limited to, opacifying pigments such as zinc oxide, titania, e.g., anatase and rutile; basic lead sulfate, magnesium silicate, silica, clays, wollastonite, talcs, mica, chromates, iron pigments, wood fluor, microballons, hard polymer particles, glass fiber or flake. Pigments can be present in the compositions of the invention in conventional amounts, i.e., between about 1 and about 40 percent by weight.
It can also be advantageous to also include as a component of the compositions of the invention a coinitiator or synergist, that is, a molecule which serves as a hydrogen atom donor. Coinitiators or synergists are known in the art, and are typically alcohols, tertiary amines or ethers which have available hydrogens attached to a carbon adjacent to a heteroatom. Such co-initiators are typically present in an amount between about 0.2 and about 25 percent by weight. Suitable compounds include triethanolamine, methyl-diethanolamine, ethyldiethanolamine and esters of dimethylamino benzoic acid. These compounds behave as co-initiators or accelerators for the primary photoinitiators and can increase the efficiency and speed of the polymerization process.
In addition, the compositions of the present invention may contain polymerization inhibitors, fillers, ultraviolet absorbers and organic peroxides.
The compositions of the invention can be applied or deposited to a surface of a substrate using conventional techniques and apparatus. The composition can be applied as a substantially continuous film; alternatively, the composition can be applied in a discontinuous pattern. Usually the compositions of the invention are fluid at ordinary operating temperatures (between ambient and up to about 60° C.).
The thickness of the deposited composition can vary, depending upon the desired thickness of the resultant cured product. Advantageously, the composition is applied to the substrate surface in an amount sufficient to provide a cured coating having a thickness between about 1 micron and about 250 mils.
Typically, the substrate is coated with the uncured photopolymerizable composition and passed under an ultraviolet providing light beam by a conveyer moving at predetermined speeds. The substrate to be coated can be, for example, metal, mineral, glass, paper, plastic, fabric, ceramic, and the like.
The active energy beams used in accordance with the present invention may be ultraviolet light or may contain in their spectra both visible and ultraviolet light. The polymerization may be activated by irradiating the composition with ultraviolet light using any of the techniques known in the art for providing ultraviolet radiation, i.e., in the range of 240 nm and 420 nm ultraviolet radiation. The radiation may be natural or artificial, monochromatic or polychromatic, incoherent or coherent and should be sufficiently intense to activate the photoinitiators of the invention and thus the polymerization. Conventional radiation sources include fluorescent lamps, mercury, metal additive and arc lamps. Coherent light sources are the pulsed nitrogen, xenon, argon ion- and ionized neon lasers whose emissions fall within or overlap the ultraviolet or visible absorption bands of the compounds of the invention. In one embodiment of the invention, the composition including the compounds of the invention is exposed to ultraviolet radiation having a wavelength of about 240 to about 420 nm.
As noted above, advantageously the compounds of the invention are appropriately substituted to possess UV spectra with significant absorption bands between 250 and 350 nm and in particular between 290 and 325 nm. Accordingly, the compounds can be irradiated with a narrow wavelength band, high pressure fill UV curing lamp known as an excimer lamp with spectral emphasis in the 250 to 350 nm range, and in particular with its peak emission wavelength at or near 308 nm, as described in U.S. Pat. No. 5,504,391, the entire disclosure of which is hereby incorporated in its entirety. The compounds of Formula (I) show a significantly elevated level of reactivity at these wavelengths. Because of the increased level of activity the photoinitiator can be used in considerably lower amounts. For example, when the compounds of the invention are used with an excimer lamp versus a medium pressure mercury lamp, only about one-fourth of the amount of photoinitiator can be required to give equivalent cure speeds. IN addition, when the same concentration of photoinitiator is used with both an excimer and a medium pressure mercury lamp the excimer lamp can provide greatly increased cure speeds. UV Spectra are provided for the excimer lamp and for MEAB in FIGS. 1 and 2, respectively.
When polymerized by exposure to UV radiation, the compositions of the invention give a substantially tack-free product which is durable for ordinary handling. The compositions of the invention are useful in any of the types of applications known in the art for photopolymerizations, including as a binder for solids to yield a cured product in the nature of a paint, varnish, enamel, lacquer, stain or ink. The compositions are particularly useful in the production of photopolymerizable surface coatings in printing processes, such as lithographic printing, screen printing, and the like.
The compounds of the invention can be prepared from an aniline compound which may be substituted at any position except the 4 position. The nitrogen atom of the aniline can be substituted using techniques known in the art. For example, the aniline can be alkylated using known techniques. In this regard, the aniline can be converted to an N-ethylaniline by reductive alkylation with acetaldehyde by methods reviewed by Rylander in “Catalytic Hydrogenation over Platinum Metals.” The N-ethylaniline may be converted to an N-ethyl, N-methylaniline by subsequent reductive alkylation with formaldehyde. These N-alkylations may also be performed with alcohol reagents by methods known in the art. The order of the N-alkylations may also be reversed in order to firstly form the N-methyl and secondly form the N-ethyl, N-methyl intermediate. The N-ethyl, N-methylaniline may be converted to the 4,4′-bis(methylethylamino)benzophenone by reaction with phosgene in the method of Michler disclosed in Chemische Berichte in the year 1876, p. 1914. This synthesis is described in detail in the following example of the conversion of N-ethylaniline, which is commercially available from First Chemical Corporation, to the photoinitiator 4,4′-bis(methylethylamino)benzophenone.
Alternative synthetic routes are disclosed in Japanese Kokai 08-12630 published Jan. 16, 1996 and in German patent 2226039, which teach the formation of a diphenylmethane and subsequent oxidation to form the benzophenone. For example, to prepare MEAB, N-ethylaniline can be reacted with formaldehyde with palladium catalyst to produce N-ethylmethyl aniline, which can be reacted with formaldehyde to give 4,4′-bis(ethylmethylamino)diphenyl methane, which is oxidized using a suitable oxidizing agent, such as chloranil/sodium chlorite. Yet another alternative route is amination of 4,4′-bis(chloro)benzophenone with methylethylamine by the method disclosed in U.S. Pat. No. 2,231,067.
The nitrogen atoms can alternatively be hydroxylated as known in the art, or one can start with hydroxy substituted aniline compounds, such as N-alkyl, N′-hydroxyalkyl anilines, commercially available, for example, from First Chemical Corporation. The hydroxyl functionality is reacted with suitable reagents as known in the art to provide the desired functionality. For example, a hydroxyl functionality can be reacted with a sulfonyl halide to provide sulfonyl groups. A hydroxyl functionality can alternatively be reacted with acryloyl halide to provide an acrylate group.
In yet another embodiment of the invention, compounds having at least one maleimide unit can be prepared according to techniques known in the art. For example, a suitably attached aromatic amine can be reacted with maleic anhydride (or a substituted maleic anhydride such as citraconic anhydride) in a polar solvent to provide the amic acid. This is followed by an acid catalyzed ring closure to form the imide. Compounds having maleimide functional groups are described in pending U.S. provisional application Serial No. 60/047,729; pending U.S. application Ser. No. 08/917,024; Z. Y. Wang, Synthetic Comm. 20(11) 1607 -1610 (1990); P. O. Tawnet et al., J.Org.Chem. 26, 15 (1961); and U.S. Pat. No. 2,542,145, the entire disclosure of each of which is hereby incorporated by reference. See also U.S. Pat. Nos. 5,629,356 and 5,468,904 and WO 96/33156, the entire disclosure of each of which is also incorporated by reference, which are directed to compounds which have polymerizable or oligomeric moieties incorporated therein.
Other compounds which can be converted to a benzophenone include, but are not limited to, N-ethyl-m-toluidine, o-toluidine, m-toluidine, 3-propylaniline, 2,3-dimethylaniline, 2,5-dimethylaniline, 2,6-dimethylaniline, 3,5-dimethylaniline, 2-cyclopentylaniline, o-anisidine, m-anisidine, 2-(methylsulfonyl)aniline, 2-fluoroaniline, 2-chloroaniline, 3-chloroaniline, 2,6-dichloroaniline, 2,3,5,6-tetrachloroaniline, 2-(trifluoromethyl)aniline, 3-(trifluoromethyl)aniline, 2-(trifluoromethoxy)aniline, 2-[(trifluoromethyl)thio]aniline, and the like.
The present invention will be further illustrated by the following non-limiting examples.
EXAMPLE 1
Synthesis of 4,4′-Bis(methylethylamino)benzophenone (MEAB)
Ethyl-aniline is methylated by reductive alkylation with formaldehyde using isopropyl alcohol as a solvent at 100° C. under 120 psi of H 2 . After the solvent is stripped the product ethylmethylaniline (NEMA) is purified by distillation at 120° C. at a pressure of 21 mm mercury (Hg). NEMA (80 g, 0.59 mol) is charged to a vessel fitted with a dry-ice condenser and is heated to 50 -60° C. Phosgene is transferred from a cylinder to a calibrated trap placed in dry-ice. After condensing 10 mL (14.3 g, 0.145 mol), the trap was connected to the vessel containing NEMA and the phosgene was added over 1 hour. After the addition was complete, the mixture was heated to 120° C. and held at this temperature for 1 hour. The mixture was cooled to 50-60° C. before 11 g (0.275 mol) of NaOH dissolved in 100 mL of water was added to hydrolyze the unreacted acid chloride. The resulting mixture was then extracted with two 100 mL portions of toluene. The product 4,4′-bis(methylethylamino)benzophenone (MEAB) was purified by chromatography on silica gel using toluene as an eluent followed by recrystallization from methylene chloride/hexane. Several grams of highly pure MEAB were obtained. No impurities were detectable by NMR; m.p. 122-124° C. NMR, IR and mass spectra were consistent with the proposed structure.
EXAMPLE 2
Use of MEAB as Photoinitiator
Michler's Ketone (also tetramethyl Michler's Ketone or TMMK), tetraethyl Michler's Ketone (also 4,4′-bis(diethylamino)benzophenone or TEMK), and MEAB were tested in curing hexanediol diacrylate compositions. The composition included 1% isopropylthioxanthone, 2% ethyl 4-N,N-dimethylaminobenzoate, 4% benzophenone, 1% aminobenzophenone compound, and the balance hexanediol diacrylate. The composition was applied as a 0.15 inch film to a substrate and cured with a Fusion UV Systems “H” bulb with 600 Watts/inch power with a belt speed of 55 feet per minute. MEAB and TMMK both required 10 passes under the lamp to obtain a well-cured hard polymer, and TEMK required 25 passes. This illustrates that MEAB and TMMK have approximately the same activity, and both are much superior to the tetraethyl compound.
EXAMPLE 3
Comparative Mutagenicity of TMMK, TEMK and MEAB
Michler's ketone (TMMK) is listed by the National Toxicology Program as “reasonably anticipated to be a carcinogen” based on the results of cancer studies in rats and mice. Seventh Annual Report on Carcinogens, U.S. Dept. Health Human Services, p. 259, 1994. Based on comparisons of mutagenicity studies with animal cancer studies, mutagens are more likely to cause cancer, to produce tumors in multiple organs, and to affect multiple species. Gold, L. S. et al., Mutat. Res. 286, 75-100 (1993).
Mutagenicity can be measured by a variety of assays. The most commonly used method is the Salmonella/Mammalian-Microsome Reverse Mutation Screening Assay (Ames Test), which commonly uses four or five strains of Salmonella bacteria to detect different types of mutations.
Michler's Ketone has been tested in the Ames Test a number times. Scribner, J. D. et al. Cancer Lett. 9, 117-121 (1980); McCarthy, D. J. et al. Mutat. Res. 119, 7-14 (1983); Dunkel, V. C. et al., Environ. Mutagen. 7 (Suppl. 5), 1-248 (1985); Zeiger, E. et al., Environ. Mol. Mutagen. 19 (Suppl. 21), 2-141 (1992). In this assay, the bacterial strain which was consistently found to have mutations when adequate concentrations of test material were used was strain Salmonella typhimurium tester strain TA98, with added mammalian metabolic activation. Dunkel, V. C. et al., Environ. Mutagen. 7 (Suppl. 5), 1-248 (1985); Zeiger, E. et al., Environ. Mol. Mutagen. 19 (Suppl. 21), 2-141 (1992).
TMMK, TEMK and MEAB were evaluated for the ability to induce reverse mutations at the histidine locus in the genome of a specific Salmonella typhimurium tester strain in the presence of an exogenous metabolic activation system of mammalian microsomal enzymes derived from Aroclor™-induced rat liver (S9). The tester strain used in the mutagenicity assay was Salmonella typhimurium tester strain TA98 with added activation. The assay was conducted using eight doses of the test article, along with the appropriate vehicle and positive controls in the presence of S9 mix (S9 homogenate was purchased from Molecular Toxicology, Inc., Annapolis, Md. 21401, Batch 0646, 43.4 mg of protein per ml). Positive controls were also plated in the absence of S9 mix. All doses of test article, vehicle, and positive controls were plated in triplicate.
1. Test Article Handling
The test article TMMK was stored at room temperature. Acetone (CAS# 67-64-1, Fisher Scientific Co., Lot 961140) was used as the vehicle. At 20 mg per ml, which was the most concentrated stock solution which could be prepared, the test article formed a clear, light yellow solution. The test article remained a solution in all succeeding dilutions prepared for the mutagenicity assay. The maximum aliquot of acetone which can be used in the test system is 200 μl. Thus, the maximum concentration which could be tested was 4,000 μg per plate. The test article and vehicle controls were plated using a 200 μl plating aliquot. Positive control articles were plated using 50 μl plating aliquot.
The test article TEMK was stored at room temperature. Acetone (CAS# 67-64-1, Fisher Scientific Co., Lot 961140) was used as the vehicle. At 100 mg per ml, which was the most concentrated stock solution prepared, the test article formed a clear, yellow solution. The test article remained a solution in all succeeding dilutions prepared for the mutagenicity assay. The test article, vehicle controls and positive control articles were plated using a 50 μl plating aliquot.
The test article MEAB was stored at room temperature. Acetone (CAS# 67-64-1, Fisher Scientific Co., Lot 961140) was used as the vehicle. At 25 mg per ml, which was the most concentrated stock solution prepared, the test article formed a clear, light yellow solution. The test article remained a solution in all succeeding dilutions prepared for the mutagenicity assay. The test article and vehicle controls were plated using a 200 μl plating aliquot. Positive control articles were plated using a 50 μl plating aliquot.
2. Mutagenicity Assay
The mutagenicity assay results for TMMK, TEMK, and MEAB are presented in Table 1. The data are presented as individual plate counts along with a mean and standard deviation.
The results of the Salmonella/Mammalian-Microsome Reverse Mutation Screening Assay (Ames Test) indicate that TMMK did cause a positive (3.9-fold) increase in the number of revertants per plate with tester strain TA98 in the presence of S9 mix. Test articles TEMK and MEAB did not cause a positive increase in the number of revertants per plate with tester strain TA98 in the presence of S9 mix. Of the three test materials, only TMMK was mutagenic. For aromatic amino or nitro compounds such as these test materials, very few which were not mutagenic in the Ames test have been found to cause tumors in animal cancer studies. Ashby, J. and Tennant, R. W., Mutat. Res. 257, 229-306 (1991). Therefore, these results suggest that MEAB has a lower potential to cause tumors than TMMK.
TABLE 1
MUTAGENICITY ASSAY RESULTS
INDIVIDUAL PLATE COUNTS
REVERTANTS PER PLATE
COMPOUND
TMMK
TEMK
MEAB
BACK
BACK
BACK
GROUND
GROUND
GROUND
SAMPLE
1
2
3
LAWN*
1
2
3
LAWN*
1
2
3
LAWN*
MICROSOMES: Rat Liver
10
22
30
1
16
36
11
1
9
20
30
1
VEHICLE CONTROL
TEST ARTICLE
(DOSE/PLATE)
3.33 μg
14
29
24
1
22
22
30
1
13
21
22
1
10.0 μg
9
19
19
1
30
24
20
1
25
28
11
1
33.3 μg
21
35
37
1
13
23
19
1
24
25
24
1
100 μg
16
12
22
1sp
28
26
24
1
20
18
20
1sp
333 μg
18
23
12
1mp
20
17
19
1sp
21
31
19
1mp
1000 μg
35
26
33
1mp
32
23
17
1mp
36
23
21
1mp
3330 μg
78
82
78
6mp
27
15
25
1mp
27
14
17
1hp
4000 μg
80
70
93
6mp
NT
NT
NT
—
NT
NT
NT
—
5000 μg
NT
NT
NT
—
27
19
19
1mp
23
23
27
1hp
POSITIVE CONTROL**
1053
920
932
1
1264
1032
1133
1
1196
1225
1226
1
**TA98 2-aminoanthracene 2.5 μg/plate
*Background Lawn Evaluation Codes:
1 = normal
2 = slightly reduced
3 = moderately reduced
4 = extremely reduced
5 = absent
6 = obscured by precipitate
sp = slight precipitate
mp = moderate precipitate (requires hand count)
hp = heavy precipitate (requires hand count)
NT = Not tested.
TABLE 2
MUTAGENICITY ASSAY RESULTS
SUMMARY
MEAN REVERTANTS PER PLATE WITH STANDARD DEVIATION
COMPOUND
TMMK
TEMK
MEAB
BACKGROUND
BACKGROUND
BACKGROUND
DOSE/PLATE
MEAN
S D.
LAWN*
MEAN
S.D.
LAWN*
MEAN
S.D.
LAWN*
MICROSOMES: Rat Liver
21
10
1
21
13
1
20
11
1
VEHICLE CONTROL
DOSE/PLATE
3.33 μg
22
8
1
25
5
1
19
5
1
10.0 μg
16
6
1
25
5
1
21
9
1
33.3 μg
31
9
1
18
5
1
24
1
1
100 μg
17
5
1sp
26
2
1
19
1
1sp
333 μg
18
6
1mp
19
2
1sp
24
6
1mp
1000 μg
31
5
1mp
24
8
1mp
27
8
1mp
3330 μg
79
2
6mp
22
6
1mp
19
7
1hp
4000 μg
81
12
6mp
NT
—
—
NT
—
—
5000 μg
NT
—
—
22
5
1mp
24
2
1hp
POSITIVE CONTROL**
968
74
1
1143
116
1
1216
17
1
**TA98 2-aminoanthracene 2.5 μg/plate
*Background Lawn Evaluation Codes.
1 = normal
2 = slightly reduced
3 = moderately reduced
4 = extremely reduced
5 = absent
6 = obscured by precipitate
sp = slight precipitate
mp = moderate precipitate (requires hand count)
hp = heavy precipitate (requires hand count)
NT = Not tested.
The foregoing examples are illustrative of the present invention and are not to be construed as limiting thereof. The invention is defined by the following claims, with equivalents of the claims to be included therein. | Novel benzophenone derivatives and methods of making and using the same are disclosed. The novel compounds can display highly active photoinitiation and photopolymerization properties. | 2 |
FIELD OF THE INVENTION
[0001] This invention relates to a novel composition containing urea and select trace elements for treating, protecting and re-epitheliazation of cutaneous wounds and damaged skin.
BACKGROUND OF THE INVENTION
[0002] Urea has been long recognized as a cosmetic ingredient in formulations acting as a humectant and moisturizer. Urea is also recognized as a medically useful keratolytic agent because of urea's ability at high concentrations to solubilize and denature protein. High concentrations of urea are also known to have an antibacterial effect.
[0003] U.S. Pat. No. 5,919,470 describes dermatological compositions using high concentrations of urea for treating xerosis and other skin conditions. This patent is being incorporated herein by reference.
[0004] Urea is known to have a strong proteolytic action and is an effective keratolytic agent particularly at an optimal concentration of 40%. Urea is very effective in dispersing epidermal keratin. Urea is non-toxic even at these high concentrations.
[0005] Trace elements play an important role in the biochemistry of living organisms including wound healing and healthy skin. Removal of necrotic tissue from wounds is essential to facilitate wound healing. Eschar and devitalized tissue may be removed by sharp, autolytic, enzymatic or surgical debridement. Urea is an excellent chemical debridement agent and can be applied directly to the wound became it is non-toxic.
[0006] Wound healing is promoted through maintenance of a moist environment and an environment which prevents microbial contamination. Both these essential wound healing aspects are provided by urea, as urea has good antimicrobial properties and can entrap water in the wound tissue/skin. Besides urea is an excellent chemical debridement agent particularly for eschar and devitalized skin and nail.
[0007] Trace amounts of zinc, copper and manganese are known to help in accelerating the healing of cutaneous wounds. Although the mechanism by which this is achieved is not clearly understood, these trace elements accelerate the re-epitheliazation of cutaneous wounds. Zinc, copper and manganese promote keratoinocyte proliferation.
[0008] There remains a need in the industry to improve upon compositions used in wound healing and repairing damaged skin.
SUMMARY OF THE INVENTION
[0009] We have found that combining urea and trace amounts of zinc, copper and manganese in a dermatological composition provides a novel approach for treating, protecting and re-epitheliazation of cutaneous wounds and the skin.
[0010] Accordingly, the present invention includes an improved method of treatment of a variety of dermatoses characterized by dry scaly skin, and cutaneous wounds using concentrations of about 21 to about 40 wt-% of urea in a suitably defined formulation containing trace elements of zinc, copper and manganese.
[0011] Thus, one aspect of the present invention is a dermatological composition including from about 21 to about 40 wt-% urea and trace elements of zinc, copper and manganese and the balance being dermatologically acceptable excipients.
[0012] The use of such high concentrations of urea combined with skin protectants of an oleaginous nature derived from petroleum and further combined with suitable emulsifiers and thickeners have been found to be effective for treating dermatological conditions manifested by dry scaly skin and cutaneous wounds without the need of traditional preservatives.
[0013] Accordingly, another aspect of the present invention is a dermatological composition including:
[0014] a) about 21 to about 40 wt-% urea;
[0015] b) trace amounts of zinc (1 ppm to 0.2%)
[0016] c) trace amounts of copper (1 ppm to 0.2%)
[0017] d) trace amounts of manganese (1 ppm to 0.2%)
[0018] e) about 5.5 to about 20 wt-% petrolatum or a synthetic or semi-synthetic hydrocarbon, or a semi-solid mixture thereof;
[0019] f) about 10 to about 20 wt-% of a liquid petrolatum or a synthetic or semi-synthetic oleaginous liquid fraction, or a mixture thereof;
[0020] g) about 0.25 to about 2 wt-% of C16-18 aliphatic straight or branched chain fatty alcohol or fatty acid, or a mixture thereof;
[0021] h) about 1 to about 5 wt-% propylene glycol;
[0022] i) about 1 to about 3 wt-% glyceryl stearate;
[0023] j) about 0.01 to about 0.5 wt-% xanthum gum; and
[0024] k) the balance being water.
[0025] Still another embodiment of the invention includes a dermatological composition containing:
[0026] a) about 21 to about 40 wt-% urea;
[0027] b) trace amounts of zinc (1 ppm to 0.2%)
[0028] c) trace amounts of copper (1 ppm to 0.2%)
[0029] d) trace amounts of manganese (1 ppm to 0.2%)
[0030] e) about 5.5 to about 20 wt-% petrolatum or a synthetic or semi-synthetic hydrocarbon, or a semi-solid mixture thereof;
[0031] f) about 10 to about 20 wt-% of a liquid petrolatum or a synthetic or semi-synthetic oleaginous liquid fraction, or a mixture thereof;
[0032] g) about 0.25 to about 2 wt-% of a C16-18 aliphatic straight or branched chain fatty alcohol or fatty acid, or a mixture thereof;
[0033] h) about 1 to about 5 wt-% propylene glycol;
[0034] i) about 1 to about 2 wt-% glyceryl stearate;
[0035] j) about 0.01 to about 0.5 wt-% xanthan gum;
[0036] k) about 0.05 to about 30 wt-% of a mixture of a carbomer and triethanolamine; and the balance being water.
[0037] Still another aspect of the present invention is a method of treating skin and cutaneous wounds by applying to an affected area in need of treatment an effective amount of a semi-solid dermatological composition containing about 21 to about 40 wt-% urea and trace amounts of zinc, copper and manganese as their respective pharmaceutically acceptable, i.e., bio-compatible salts.
DETAILED DESCRIPTION
[0038] The dermatological composition of the present invention is a semi-solid at room temperature. A preferred application of the formulation is a cream which contains a petroleum based liquid and solid fraction as skin protectants when applied to skin. A preferred application of the formulation is for application to cutaneous wounds and damaged skin.
[0039] The cream composition has advantageous properties for the treatment of dry scaly skin clinically characterized as xerosis and for the temporary relief of itching associated with various pathological dermatological conditions. The formulation produces a keratolytic action found beneficial in the treatment of ichthyosis, psoriasis and atopic dermatitis. Application of the cream to the skin as needed provides relief of the conditions.
[0040] Trace amounts of the zinc, copper and manganese metals range in the composition from about 1 part per million (ppm) to about 0.2 wt-%, or from about 10 ppm to about 0.2 wt-%, of active metal sourced from its corresponding pharmaceutically acceptable, bio-compatible salts. Examples of bio-compatible salts of manganese are manganese carbonate, chloride, gluconate, glycerophosphate, lactate, or nitrate. Examples of copper bio-compatible salts include copper acetate, bromide, carbonate, chloride, citrate, gluconate, glycinate, iodide or nitrate. Bio-compatible zinc salts include but are not limited to zinc acetate, bromide, carbonate, chloride, citrate, gluconate, glycinate, lactate, nitrate, or sulfate. The preferred salts for these metals are the gluconate salts. These salts are commercially available, for example, from Spectrum Chemical and Laboratory Products, Gardena, Calif.
[0041] In addition to containing about 21 to about 40 wt-% of urea and trace amounts of zinc, copper and manganese as their bio-compatible salts, the composition of the present invention includes skin protectants which include a combination of semi-solid and liquid petroleum fractions. The semi-solid skin protectant is contained in about 5.5 to about 20 wt-% and includes petrolatum or a synthetic or semi-synthetic hydrocarbon of the same nature as petrolatum. Mixtures of such ingredients can also be used. The preferred semi-solid material is petrolatum, commercially available from a wide variety of sources.
[0042] The liquid portion skin protectant is a liquid petrolatum and contained in the composition in about 5 to about 30 wt-%. This material can include any synthetic or semi-synthetic oleaginous liquid fraction. A preferred embodiment is mineral oil which is a liquid mixture of hydrocarbons obtained from petroleum.
[0043] Another preferred ingredient encompassed in the composition of the present invention is propylene glycol which may be contained up to about 5 wt-% in the composition, preferably in the range of from about 1 to about 5 wt-%.
[0044] Although not to be held by theory, it is believed that the mild antibacterial properties of the urea and propylene glycol allow the composition of the present invention to be free of conventional preservatives such as methyl paraben, propyl and butyl imidazolidinylurea, diazolidinylurea, methylchloroisothiazolinone and methylisothiazolinone.
[0045] In addition to the above embodiments, the present composition also contains dermatologically acceptable excipients, such as for example emulsifiers and thickeners. Among these are, for example, C16 to C18 straight or branched chain fatty alcohols or fatty acids or mixtures thereof. Preferably these include cetyl alcohol, stearyl alcohol, stearic acid, palmitic acid, or mixtures thereof. Fatty acids or fatty alcohols may be present in from about 0.25 to 2 wt-%.
[0046] Another ingredient useful in the composition of the present invention may be glyceryl stearate, which is a monoester of glycerine and stearic acid, or other suitable forms of glyceryl stearate, for example glyceryl stearate SE, which is a commercially available self-emulsifying grade of glycerol stearate that contains some sodium and/or potassium stearate. Glyceryl stearate may be in the composition anywhere from about 1 to about 3 wt-%.
[0047] Xanthan gum is another ingredient which may be used in the present invention. Xanthan gum is a high molecular weight heteropolysaccharide gum produced by pure-culture fermentation of a carbohydrate with Xanthomonas campestris. The gum is also commercially available from various sources.
[0048] As part of the dermatologically acceptable excipients, the composition includes thickeners which provide a high viscosity cream designed to remain in place upon application to the skin. Preferred thickeners include a mixture of triethanolamine and a carbomer combined together and added to the composition in an amount totaling anywhere from about 0.05 to 30 wt-%. Triethanolamine is purchased as Trolamine NF from BASF. The carbomers come in various molecular weights and identified by numbers. These are otherwise known as Carbopol. A preferred embodiment of the present invention is Carbopol 940. The carbomer or Carbopols are resins which are known thickening agents. They are homopolymers of acrylic acid crosslinked with an allyl ether of pentaerythritol, an allyl ether of sucrose or an allyl ether of propylene. The carbomer is present in the composition as a thickener and also is used to suspend and stabilize the emulsion. Although Carbopol 940 is preferably used in the present invention, other analogs may also be used such as Carbomer 910, 2984, 5984, 954, 980, 981, 941 and 934. Carbopol ETD 2001, 2020, and 2050 and Ultrez 20 are also commercially available and can be used since they are similar in chemistry and function.
[0049] A typical formulation representing a particular embodiment of the present invention is illustrated as follows:
Ingredient % w/w Purified water 36.149 Urea, USP 40.000 Zinc (as bio-compatible Salt) Trace* Copper (as bio-compatible Salt) Trace* Manganese (as bio-compatible Salt) Trace* Carbopol 940 0.150 Petrolatum 5.940 Mineral oil 12.060 Glyceryl stearate 1.875 Cetyl alcohol 0.626 Propylene glycol 3.000 Xanthan gum 0.050 Trolamine NF 0.150 TOTAL 100.000
[0050] Glossary of Ingredients
[0051] The formulation of the present invention has been defined above and more specifically exemplified in the following examples. Since the formulation employs various ingredients, some of the ingredients have been defined generically and by common name. In addition, the following is a glossary of technical names and trade names with manufacturing sources for some of the ingredients employed in the formulation of the present invention.
[0052] Mineral Oil
[0053] Definition
[0054] Mineral oil is a liquid mixture of hydrocarbons obtained from petroleum.
[0055] Technical Names
[0056] Heavy Mineral Oil
[0057] Light Mineral Oil
[0058] Liquid Paraffin
[0059] Paraffin Oil
[0060] Trade Names
[0061] Benol White Mineral Oil (Witco/Sonneborn)
[0062] Blandol White Mineral Oil (Witco/Sonneborn)
[0063] Britol 6 (Witco Corporation)
[0064] Britol 7 (Witco Corporation)
[0065] Britol 9 (Witco Corporation)
[0066] Britol 20 (Witco Corporation)
[0067] Britol 24 (Witco Corporation)
[0068] Britol 35 (Witco Corporation)
[0069] Britol 50 (Witco Corporation)
[0070] Carnation White Mineral Oil (Witco/Sonneborn)
[0071] Crystosol NF 70 (Witco Corporation)
[0072] Crystosol NF 90 (Witco Corporation)
[0073] Crystosol USP 200 (Witco Corporation)
[0074] Crystosol USP 240 (Witco Corporation)
[0075] Crystosol USP 350 (Witco Corporation)
[0076] Drakeol 5 (Penreco)
[0077] Drakeol 6 (Penreco)
[0078] Drakeol 7 (Penreco)
[0079] Drakeol 8 (Penreco)
[0080] Drakeol 9 (Penreco)
[0081] Drakeol 10 (Penreco)
[0082] Drakeol 13 (Penreco)
[0083] Drakeol 15 (Penreco)
[0084] Drakeol 19 (Penreco)
[0085] Drakeol 21 (Penreco)
[0086] Drakeol 32 (Penreco)
[0087] Drakeol 34 (Penreco)
[0088] Drakeol 35 (Penreco)
[0089] Draketex 50 (Penreco)
[0090] Ervol White Mineral Oil (Witco/Sonneborn)
[0091] Gloria White Mineral Oil (Witco/Sonneborn)
[0092] Kaydol White Mineral Oil (Witco/Sonneborn)
[0093] Klearol White Mineral Oil (Witco/Sonneborn)
[0094] Parol 70 (Penreco)
[0095] Parol 80 (Penreco)
[0096] Parol 100 (Penreco)
[0097] PD-23 White Mineral Oil (Witco/Sonneborn)
[0098] Peneteck (Penreco)
[0099] Protol White Mineral Oil (Witco/Sonneborn)
[0100] Superla Mineral Oil #5 NF (Amoco Lubricants)
[0101] Superla Mineral Oil #6 NF (Amoco Lubricants)
[0102] Superla Mineral Oil #7 NF (Amoco Lubricants)
[0103] Superla Mineral Oil #9 NF (Amoco Lubricants)
[0104] Superla Mineral Oil #10 NF (Amoco Lubricants)
[0105] Superla Mineral Oil #13 NF (Amoco Lubricants)
[0106] Superla Mineral Oil #18 NF (Amoco Lubricants)
[0107] Superla Mineral Oil #21 NF (Amoco Lubricants)
[0108] Superla Mineral Oil #31 NF (Amoco Lubricants)
[0109] Superla Mineral Oil #35 NF (Amoco Lubricants)
[0110] Uniwhite Oil 55 (UPI)
[0111] Uniwhite Oil 70 (UPI)
[0112] Uniwhite Oil 85 (UPI)
[0113] Uniwhite Oil 130 (UPI)
[0114] Uniwhite Oil 185 (UPI)
[0115] Uniwhite Oil 205 (UPI)
[0116] Uniwhite Oil 350 (UPI)
[0117] Glyceryl Stearate
[0118] Empirical Formula
C 21 H 42 O 4
[0119] Definition
[0120] Glyceryl stearate is the monoester of glycerin and stearic acid. It conforms generally to the formula:
CH 3 (CH 2 ) 16 COOCH 2 CN(OH)CH 2 OH
[0121] Technical Names
[0122] 2.3-Dihydroxypropyl octadecanoate
[0123] Glyceryl monostearate
[0124] Monostearin
[0125] Octadecanoic acid, 2.3-dihydroxypropyl ester
[0126] Octadecanoic acid, monoester with 1,2,3-propanetriol
[0127] Trade Names
[0128] Aldo HMS (Lonza Inc./Lonza Ltd.)
[0129] Aldo MS (Lonza Inc./Lonza Ltd.)
[0130] Aldo MSLG (Lonza Inc./Lonza Ltd.)
[0131] Alkamuls GMS (Rhone-Poulenc)
[0132] Arlacel 129 (ICI)
[0133] Atmos 150 (ICI)
[0134] Atmul 84 (ICI)
[0135] Atmul 124 (ICI)
[0136] Capmul GMS (Karishamns Lipid Specialties)
[0137] Ceral MN (Fabriquimica)
[0138] Ceral MNT (Fabriquimica)
[0139] Cerasynt GMs (ISP Van Dyk)
[0140] Cerasynt SD (ISP Van Dyk)
[0141] Cithrol GMS N/E (Croda Surfactants Ltd.)
[0142] CPH-53-N (Hall)
[0143] CPH-144-N (Hall)
[0144] Cutina GMS (Henkel)
[0145] Cutina MD (Henkel)
[0146] Cutina MD-A (Henkel)
[0147] Dimodan PM (Grinsted)
[0148] Dimodan PM 300 (Grinsted)
[0149] Elfacos GMS (Akzo BV)
[0150] Emerest 2400 (Henkel/Organic Products)
[0151] Empilan GMS NSE (Albright & Wilson)
[0152] Emuldan FP 40 (Grinsted)
[0153] Emuldan HA 60 (Grinsted)
[0154] Emuldan HLT 40 (Grinsted)
[0155] ESTOL GMS90 1468 (Unichema)
[0156] ESTOL GMSveg 1474 (Unichema)
[0157] Geleol (Gattefosse)
[0158] Grillomuls S 40 (Grillo-Werke)
[0159] Grillomuls S 60 (Grillo-Werke)
[0160] Grillomuls S 90 (Grillo-Werke)
[0161] Hefti GMS-33 (Hefti)
[0162] Hodak GMS (Calgene)
[0163] Imwitor 191 (Huls AG/Huls America)
[0164] Imwitor 900 (Huls AG/Huls America)
[0165] Kemester 5500 (Witco)
[0166] Kemester 6000 (Witco)
[0167] Kessco GMS (Akzo BV)
[0168] Lanesta 24 (Lanaetex)
[0169] Lasemul 92 AE (Industrial Quimica)
[0170] Lasemul 92 AE/A (Industrial Quimica)
[0171] Lasemul 92 N 40 (Industrial Quimica)
[0172] Lexemul 503 (Inolex)
[0173] Lexemul 515 (Inolex)
[0174] Lexemul 55G (Inolex)
[0175] Lipo GMS 410 (Lipo)
[0176] Lipo GMS 450 (Lipo)
[0177] Lipo GMS 600 (Lipo)
[0178] Nikkol MGS-DEX (Nikko)
[0179] Norfox GMS (Norman, Fox & Co.)
[0180] Norfvox GMS-SE (Nornan, Fox & Co.)
[0181] Prodhybase GLA (Prod'Hyg)
[0182] Protachem 26 (Protameen)
[0183] Protechem G 5509 (Protameen)
[0184] Protechem GMS-540 (Protameen)
[0185] Protechem HMS (Protameen)
[0186] Sterol GMS (Auschem)
[0187] Tegin 90 (Goldschmidt)
[0188] Tegin 515 (Goldschmidt)
[0189] Tegin 4011 (Goldschmidt)
[0190] Tegin 4100 (Goldschmidt)
[0191] Tegin GRB (Goldschmidt)
[0192] Tegin ISO (Goldschmidt)
[0193] Tegin M (Goldschmidt)
[0194] Tegin MAV (Goldschmidt)
[0195] Unitina MD (UPI)
[0196] Unitina MD-A (UPI)
[0197] Unitolate GS (UPI)
[0198] Witconol 2400 (Witco)
[0199] Witconol 2401 (Witco)
[0200] Witconol MST (Witco SA)
[0201] Witconol MST (Witco)
[0202] Zohar GLST (Zohar)
[0203] Definition
[0204] Glyceryl stearate SE is a self-emulsifying grade of glyceryl stearate (q.v.) that contains some sodium and/or potassium stearate.
[0205] Trade Names
[0206] Aldo MSD (Lonza Inc./Lonza Ltd.)
[0207] Ceral ME (Fabriquimica)
[0208] Ceral MET (Fabriquimica)
[0209] Ceral TN (Fabriquimica)
[0210] Cerasynt Q (ISP Van Dyk)
[0211] Cithrol GMS S/E (Croda Surfactants Ltd.)
[0212] Cutina KD-16 (Henkel)
[0213] Dermalcare GMS/SE (Rhone-Poulenc)
[0214] Dracorin GMS SE O/W 2/008475 (Dragoco)
[0215] Emerest 2407 (Henkel/Organic Products)
[0216] Empilan GMS SE (Albright & Wilson)
[0217] Emuldan HA 32/S3 (Grinsted)
[0218] ESTOL BMSse 1462 (Unichema)
[0219] Hefti GMS-33-SES (Hefti)
[0220] Hodag GMS-D (Calgene)
[0221] Imwitor 960 (Huls Ag/Huls America)
[0222] Kemester 6000 SE (Witco)
[0223] Lamecreme KSM (Grunau)
[0224] Lanesta 40 (Lanaetex)
[0225] Lexemul 530 (Inolex)
[0226] Lexemul T (Inolex)
[0227] Lipo GMS 470 (Lipo)
[0228] Mazol GMSD-K (PPG)
[0229] Prodhybase GLN (Prod'Hyg)
[0230] REWOMUL MG SE (Rewo Chemische)
[0231] Tegin (Goldschmidt)
[0232] Tegin Spezial (Goldschmidt)
[0233] Tegin V (Goldschmidt)
[0234] Unitolate GMS-D (UPI)
[0235] Witconol 2407 (Witco)
[0236] Cetyl Alcohol
[0237] Empirical Formula
C 16 H 34 O
[0238] Definition
[0239] Cetyl alcohol is the fatty alcohol that conforms generally to the formula:
CH 3 (CH 2 ) 14 CH 2 OH
[0240] Technical Names
[0241] 1-Hexadecanol
[0242] n-Hexadecyl alcohol
[0243] Palmityl alcohol
[0244] Trade Names
[0245] Adol 52 (Witco)
[0246] Adol 520 (Witco)
[0247] Adol 52-NF (Witco)
[0248] Adol 520-NF (Witco)
[0249] Cachalot C-50 (Michel)
[0250] Cachalot C-51 (Michel)
[0251] Cachalot C-52 (Michel)
[0252] Cetaffine (Laserson & Sabetay)
[0253] Cetal (Amerchol)
[0254] Cetyl Alcohol (Rhone-Poulenc)
[0255] CO-1695 (Procter & Gamble)
[0256] Crodacol C-70 (Croda Chemicals, Inc.)
[0257] Crodacol C90 (Croda Chemicals Ltd.)
[0258] Crodacol C-95 (Croda, Inc.)
[0259] Fancol CA (Fanning)
[0260] Hyfatol 16-95 (Aarhus)
[0261] Hyfatol 16-98 (Aarhus)
[0262] Lanette 16 (Henkel)
[0263] Lanol C (SEPPIC)
[0264] Laurex 16 (Albright & Wilson)
[0265] Lipocol C (Lipo)
[0266] Stearic Acid
[0267] Empirical Formula
C 18 H 36 O 2
[0268] Definition
[0269] Stearic acid is the fatty acid that conforms generally to the formula:
CH 3 (CH 2 ) 16 COOH
[0270] Trade Names
[0271] Crosterene SA4310 (Croda Universal Ltd.)
[0272] Dar-Chem 14 (Darling)
[0273] Emersol 120 (Henkel/Emery)
[0274] Emersol 132 (Henkel/Emery)
[0275] Emersol 150 (Henkel/Emery)
[0276] Glycon DP (Lonza Inc./Lonza Ltd.)
[0277] Glycon P-45 (Lonza Inc./Lonza Ltd.)
[0278] Glycon S-65 (Lonza Inc./Lonza Ltd.)
[0279] Glycon S-70 (Lonza Inc./Lonza Ltd.)
[0280] Glycon S-90 (Lonza Inc./Lonza Ltd.)
[0281] Glycon TP (Lonza Inc./Lonza Ltd.)
[0282] Hy-Phi 1199 (Darling)
[0283] Hy-Phi 1303 (Darling)
[0284] Hy-Phi 1401 (Darling)
[0285] Hystrene 4516 (Witco)
[0286] Hystrene 5016 (Witco)
[0287] Hystrene 7018 (Witco)
[0288] Hystrene 9718 (Witco)
[0289] Industrene 5016 (Witco)
[0290] Industrene 7018 (Witco)
[0291] Karacid 1890 (Akzo BV)
[0292] Neo-Fat 18 (Akzo)
[0293] Neo-Fat 18-54 (Akzo)
[0294] Neo-Fat 18-55 (Akzo)
[0295] Neo-Fat 18-61 (Akzo)
[0296] Pearl Stearic (Darling)
[0297] PRIFAC 2981 (Unichema)
[0298] Pristerene 4900 (Unichema)
[0299] Pristerene 4901 (Unichema)
[0300] Pristerene 4902 (Unichema)
[0301] Pristerene 4904 (Unichema)
[0302] Pristerene 4905 (Unichema)
[0303] Pristerene 4910 (Unichema)
[0304] Pristerene 4911 (Unichema)
[0305] Pristerene 4915 (Unichema)
[0306] Pristerene 4921 (Unichema)
[0307] Pristerene 4968 (Unichema)
[0308] Pristerene 9550 (Unichema)
[0309] Safacid 18 (Pronova)
[0310] Safacid 16/18 CR (Pronova)
[0311] Unifat 54 (UPI)
[0312] Unifat 55L (UPI)
[0313] Stearyl Alcohol
[0314] Empirical Formula
C 18 H 38 O
[0315] Definition
[0316] Stearyl alcohol is the fatty alcohol that conforms generally to the formula:
CH 3 (CH 2 ) 16 CH 2 OH
[0317] Technical Name
[0318] 1-Octadecanol
[0319] Trade Names
[0320] Adol 63 (Witco)
[0321] Adol 61-NF (Witco)
[0322] Adol 62-NF (Witco)
[0323] Adol 620-NF (Witco)
[0324] Cachalot S-53 (Michel)
[0325] Cachalot S-54 (Michel)
[0326] Cachalot S-56 (Michel)
[0327] CO-1895 (Procter & Gamble)
[0328] Crodacol S-70 (Croda, Inc.)
[0329] Crodacol S-95 (Croda, Inc.)
[0330] Crodacol S-95 (Croda Chemicals, Inc.)
[0331] Fancol SA (Fanning)
[0332] Hyfatol 18-95 (Aarhus)
[0333] Hyfatol 18-98 (Aarhus)
[0334] Lanette 18 (Henkel)
[0335] Lanol S (SEPPIC)
[0336] Laurex 18 (Albright & Wilson)
[0337] Lipocol S (Lipo)
[0338] Stearal (Amerchol)
[0339] Stearyl Alcohol (Rhone-Poulenc)
[0340] Steraffine (Laserson & Sabetay)
[0341] Unihydag WAX-18 (UPI)
[0342] Palmitic Acid
[0343] Empirical Formula
C 16 H 32 O 2
[0344] Definition
[0345] Palmitic acid is the fatty acid that conforms generally to the formula:
CH 3 (CH 2 ) 14 COOH
[0346] Technical Name
[0347] n-Hexadecanoic acid
[0348] Trade Names
[0349] Crodacid PD3160 (Croda Universal Ltd.)
[0350] Edenor L2SM (Henkel)
[0351] Emersol 142 (Henkel/Emery)
[0352] Emersol 144 (Henkel/Emery)
[0353] Hystrene 7016 (Witco)
[0354] Hystrene 9016 (Witco)
[0355] Kartacid 1692 (Akzo BV)
[0356] Neo-Fat 16 (Akzo)
[0357] Neo-Fat 16-54 (Akzo)
[0358] Neo-Fat 16-56 (Akzo)
[0359] Neo-Fat 16-S (Akzo)
[0360] PRIFAC 2962 (Unichema)
[0361] Prifac 2690 (Unichema)
[0362] Trade Name Mixture
[0363] N.S.L.E. (Sederma)
[0364] Propylene Formula
C 3 H 8 O 2
[0365] Definition
[0366] Propylene glycol is the aliphatic alcohol that conforms generally to the formula: CH 3 CH(OH)CH 2 OH
[0367] Technical Name
[0368] 1,2-Propanediol
[0369] Trade Names
[0370] Lexol PG-865 (855) (Inolex)
[0371] 1,2-Propylene Glycol USP (BASF)
[0372] Xanthan Gum
[0373] Definition
[0374] Xanthan gum is a high molecular weight hetero polysaccharide gum produced by a pure-culture fermentation of a carbohydrate with Xathomonas campestris.
[0375] Technical Names
[0376] Corn sugar gum
[0377] Xanthan
[0378] Trade Names
[0379] Kelgum CG (Calgon)
[0380] Keltrol (Kelco)
[0381] Keltrol CG 1000 (Calgon)
[0382] Keltrol CG BT (Calgon)
[0383] Keltrol CG F (Calgon)
[0384] Keltrol CG GM (Calgon)
[0385] Keltrol CG RD (Calgon)
[0386] Keltrol CG SF (Calgon)
[0387] Keltrol CG T (Calgon)
[0388] Keltrol CG TF (Calgon)
[0389] Kelzon (Kelco)
[0390] Merezan 8 (Meer)
[0391] Merezan 20 (Meer)
[0392] Rhodigel (Vanderbilt)
[0393] Rhodigel (Rhone-Poulenc)
[0394] Rhodopol SC (Rhone-Poulenc)
[0395] Xanthan gum (Jungbunzlauer)
[0396] Triethanolamine
[0397] Empirical Formula
C 6 H 15 O 3 N
[0398] Definition
[0399] Triethanolamine is an alkanolamine that conforms generally to the formula:
N(CH 2 CH 2 OH) 3
[0400] Technical Names
[0401] Ethanol, 2,2′2″-Nitrilotris-2,2′,2″-Nitrilotris[Ethanol]
[0402] TEA
[0403] Trolamine
[0404] Trade Name
[0405] Triethanolamine Pure C (BASF)
EXAMPLE
[0406] The typical formulation illustrated above is prepared commercially as follows:
Ingredient Batch Units Purified water 1084.47 Gm Urea USP 1200.00 Gm Zinc (as bio-compatible salt) 0.5 Mg Copper (as bio-compatible salt) 0.5 Mg Manganese (as bio-compatible salt) 0.5 Mg Carbopol 940 4.50 Gm Petrolatum 178.20 Gm Mineral oil 361.80 Gm Glyceryl stearate 56.25 Gm Cetyl alcohol 18.78 Gm Propylene glycol 90.00 Gm Xanthan gum 1.50 Gm Trolamine NF 4.50 Gm
[0407] The above product was manufactured as follows:
[0408] Step 1
[0409] Placed in Tank A and heated to 80-82° C. with constant stirring using a lightning mixer were the following:
[0410] 1069.47 Gm purified water
[0411] 1200.00 Gm urea
[0412] After the urea dissolved added the zinc, copper and manganese salts and mixed to dissolve.
[0413] Step2
[0414] In a separate tank heated to 70-75° C. with constant stirring using a lightning mixer was placed:
[0415] 178.20 Gm petrolatum
[0416] 361.80 Gm mineral oil
[0417] 56.25 Gm glyceryl stearate
[0418] 18.78 Gm cetyl alcohol
[0419] Step 3
[0420] Using a lightning mixer in Tank A, there was dispersed 4.50 Gm Carbopol 940 added in small increments.
[0421] Step 4
[0422] The solution in Tank A was kept at 70-75° C., while stirring, by dispersing 90 Gm of propylene glycol and 1.5 Gm of xanthan gum. This was followed by the addition of 4.5 Gm of Trolamine, triethanolamine, and 15 Gm of purified water.
[0423] When the oil phase in the second tank was completely melted, it was added to the first tank and mixing continued for approximately 15 minutes. The mixture was then cooled to about room temperature. The bulk product was sampled for testing and packaged into conventional containers for use as a cream. Other dosage forms can be made appropriate for topical applications including cutaneous wounds. In particular, a paste formulation is preferred for application on wounds. | Described are dermatological compositions for treating, protecting and re-epitheliazing cutaneous wounds and damaged skin, such compositions including about 21 to about 40% urea and trace amounts of zinc, copper and manganese in the form of their respective pharmaceutically acceptable salts. | 8 |
CROSS-RELATED APPLICATION
This application is a continuation of copending application 531,818 filed Dec. 11, 1974 and now abandoned.
FIELD OF THE INVENTION
The invention relates to methods of mass producing bulb sockets for plug-in miniature lights directly on an electric cord.
BACKGROUND AND PRIOR ART
It is known to use miniature lamps with or without plug bases for decorating Christmas trees and for other purposes. These require suitable sockets on the electric wire. A process is also known for manufacturing, continuously and automatically, sockets for plug-in microlamps on a flexible two-wire cable as an electric line cord insures feed continuity of the cord throughout the working phases of preparation whereafter injection molding of a socket is effected for each completed cycle. Since the working cycle comprises several phases and while the various mechanical operations take place very quickly, the socket-molding phase involves more time to enable the molded object to cool. This means that the time involved in completing the cycle is conditioned upon the time involved in the socket-molding phase.
SUMMARY OF THE INVENTION
An object of this invention is to provide improvements in the above-mentioned process and to produce a notably better product. The invention is based essentially on the concept of carrying out the various operations of cable preparation and socket molding simultaneously at various points of the cable with the expedient of arranging the different cable portions that are taken in and unite the sockets two by two according to a comb-like string or series of objects. For this purpose a double-wire cable is no longer used and only a single-pole cable is required. The invention contemplates arranging the winding cable with its various intervals on a cylinder, rotating the cylinder on its horizontal axis, with an intermittent forward motion that corresponds to the speed of movement of the string; distributing working stations for the different operations, fixed and independent of the cable support, along one or both base circumferences of said cylinder, i.e., in front of the loops or bends of the string; placing a mold for the molding of the sockets in front of each bend of the string and integral with the cable support, so that each mold is used but once for every each working cycle, thereby enabling the mold to remain closed after injection of the thermosplastic material for the time it takes the molded object to cool.
This invention will next be described in greater detail by referring to the attached drawings which schematically show the series of working phases which make up the operation cycle.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a diagrammatic view showing the operation of the method of the invention,
FIG. 2 is a detail of the wire in one stage of operation of the method,
FIG. 3a is a plan view of a further detail in another stage of operation of the method,
FIG. 3b is an elevation view of the detail of FIG. 3a,
FIG. 3c is a section taken along line 3c--3c in FIG. 3b,
FIG. 4a is a sectional view taken on line 4a--4a in FIG. 4b, and
FIG. 4b is a sectional view taken on line 4b--4b in FIG. 4a.
DETAILED DESCRIPTION
FIG. 1 shows the arrangement of a portion of the electric wire according to a comb-like string, on which the operations are carried out at six different points on both sides of the string. Stage 1 represents the first phase of the locking of the wire. Stage 2 represents the second phase of cutting the wire at each end of each bend or turn of the string. Stage 3 represents the third phase of baring the wire at a portion of the end of each bend of the string. Stage 4 represents the fourth phase of applying a blade-like contact on each portion of the barred wire, the two contacts provided for the same socket being opposite each other and parallel. Stage 5 represents the fifth phase of thermoplastic injection molding of a socket in correspondence with each pair of blade-like contacts. Stage 6 represents the sixth phase of inserting a plug-in microlamp in each of the molded sockets.
FIG. 2 is a plan view of a fragment of wire showing a bared end portion and FIGS. 3a-3b represent plan and side views of a blade-like contact applied to the bared end of said wire fragment, FIG. 3c being a section through the base of the applied contact. FIG. 4 is an end sectional view of a socket and FIG. 4b is a longitudinal section through the socket.
According to the process of this invention, reduced to its essential features and with reference to the attached drawings there are effected the steps comprising causing intermittent forward movement of flexible single-pole cable 1, properly tensioned and having a purposely serpentine or comb-like string configuration and carrying out all phases of the working cycle, each at one loop or bend of the string at one or both ends of the string so that the operations are effected simultaneously on this cable at constant time intervals.
These phases in progressive order of movement of the cable include the first phase during which the cable is locked in correspondence at each bend 2; the second phase during which a portion of a cable forming the central part 3 of each bend of the string is cut; the third phase during which the insulation at 4 is removed from the cable at the cut-off ends of each bend for baring the wire 5; the fourth phase during which two blades 6 of electroconductive material are clinched on symmetrically and opposite one another with respect to the plane of symmetry 7 of each bend; the fifth phase during which a socket 8 is injection-molded of thermoplastic material onto the wire around a a pair of blades; and the sixth phase during which a miniature lamp 9 is placed into the now molded socket 8. When the cable string has gone through the entire course, passing the front of the various working stations, the manufactured article is finished.
It is to be understood that the cable 1 is periodically fed or drawn from a cylinder (not shown) into the support (shown in dotted outline), by a conventional looper (not shown) such that the cable is wound with the alternating upper and lower loops or bends in the supports where the cable is clamped. The support undergoes stepwise movement in synchronization with the cable feed to carry the cable through the successive stages of operation. FIG. 1 shows two loops or bends formed in the cable at the top and bottom and it is possible to provide a plurality of pairs of top and bottom bends in which case a corresponding plurality of operations would be carried out at each state of operation.
It is to be further appreciated that despite the separation of adjacent wires at the bends during cutting, these are ultimately re-united by the molding of the sockets to provide continuity of the finished string.
As regards the product obtained by the process, this comprises an electric line of decorative lights in series with any number of miniature lamps arranged in series. Additionally, the side surface of the sockets is totally or at least partially knurled to facilitate handling during application. Finally, the sockets 8 can be equipped with two flexible and elastic stalk-like pieces 10 coming out of the bottom of the base and/or with a hook 11 attached to the side surface to enable the sockets to be clipped onto whatever is to be decorated.
In practice, the details of execution can vary as regards shape, sizes and arrangement of the elements, and nature of the materials used, remaining always within the purview of the original concept and therefore within the limits defined by the appended claims. | A method for mass producing bulb sockets for plug-in miniature lights directly on an electric cable comprising successively passing a single line flexible cable through a plurality of stages of operation inclusive of a socket molding station where sockets are heat molded on the cable, and effecting the operation at the stages simultaneously to continuously produce a completed cable. | 5 |
This is a continuation of application Ser. No. 213,944, filed Dec. 30, 1971, now abandoned.
BACKGROUND OF THE INVENTION
The present invention has for its object an electrical connection between groups of lead plates for electric accumulator elements, and a method for forming connections of that type or others.
No absolutely satisfactory solution has been found for the problem of making sealed electric connections between two adjacent accumulator elements, either from the point of view of perfect sealing of the connection, or from the point of view of easy production thereof. The Applicants have perfected connections having excellent sealing characteristics, which are the object of their French patent application No. 69.04 068 of Feb. 19, 1969, but requiring the use of at least one seal per connection. They have also studied an extremely rapid method for manufacturing rods for connecting together plates of same polarity of an element, and connections of rods for plates of opposite polarity of adjacent elements, the plates being arranged in the accumulator box already provided with its lid, which was the object of their French Pat. No. 69.08 974 of March 26, 1969. This method does not, however, enable the production of connections between adjacent elements as well sealed as the sealed connections in their aforementioned patent application, and requires the use of certain tooling adapted to the dimensions, and more particularly, to the number of elements, of the accumulators to be produced.
With a view to making strictly sealed connections, the Applicants have described, in French Pat. No. 69.39 218, a method for forming connections between lead plates of electric accumulators, in which method an elementary mould is fitted on the plate lugs arranged in an element of the accumulator, then molten lead is run into that mould so as to connect the plate lugs together by rods, and the rods of the plates of opposite polarity are connected through holes provided in the partition separating two adjacent elements, these operations being made preferably before the fixing of the accumulator lid on its box.
The mould provided for surrounding the plate lugs of same polarity has the general shape of a channel, preferably having a flat bottom, whose bottom is drilled with rectangular openings having a cross-section firstly equal to those of the plate lugs, then tapering downwardly, preferably in the shape of a truncated pyramid with a rectangular base.
SUMMARY OF THE INVENTION
The present invention proposes to make such connections by an appreciably modified method, using, more particularly, either an elementary mould having a different structure, or parts moulded onto the accumulator box.
The invention, therefore, has for its object a method of forming lead plates on an electric accumulator having several elements, and for interconnecting the plates of the elements by melting the plate lugs, in which the plate lugs arranged in an element of the accumulator are inserted in the openings made in the bottom of at least one elementary mould, the plate lugs then are connected together by rods produced by melting the lead, and the connection of the rods associated with the plates of opposite polarities of two adjacent elements of the accumulator is made, these operations being carried out preferably before the fixing of the accumulator lid on its box, characterised in that the elementary mould comprises two channels, each of these having the plate lugs of same polarity fitted in them.
It must be understood that the method which is the object of the present invention enables electrical connections having the advantage of sealing previously obtained to be produced.
It must be stated, moreover, that such a method enables the avoidance of the use of connection rods having special shapes formed by moulding, and having an appreciable cost price.
Also, it should be observed that such a process ensures a reduction in the length of the electric connection circuit as well as an appreciable gain in the weight of the lead alloy used.
Further, it should be noted that the upper faces of the channels of the walls of the box, as well as of the partitions, are arranged substantially in a same plane, so that fixing of the accumulator lid on the box is effected in a particularly easy way by thermo-welding.
Likewise, the implementing of the invention enables the avoidance of the use of numerous tools such as welding combs and the like adapted to each type of accumulator, with a view to making such connections. Moreover, it is not necessary to create a special work station, which would be difficult to automate, on the production line.
It should be observed also that the moulds are inserted in the elements of the battery and remain therein after the lid has been welded. The result is that they subsequently resist all possible deformation of the walls, thus ensuring a forming function.
Moreover, they can, to great advantage, comprise a reference of the electrolyte level, as well as a deflecting orifice preventing any splashing of acid towards the upper part of the battery.
BRIEF DESCRIPTION OF THE DRAWINGS
Other characteristics and advantages of the invention will become apparent from the following description, given by way of a merely illustrating and non-limiting example, with reference to the accompanying drawings and diagrams, in which:
FIG. 1 is a perspective view of an accumulator box comprising an elementary mould consisting of a channel common to two adjacent elements, and moulded onto the box, according to the present invention;
FIG. 2 is a perspective view of a self-contained elementary mould provided with two channels according to the invention, comprising an electrolyte level indicator;
FIG. 3 is an elevational view in section of an elementary mould according to the invention, inserted in an element of the battery, and resting on the separators;
FIG. 4 is a sectional view taken substantially along the line I--I of FIG. 3;
FIG. 5 is an elevational view in section of an elementary mould according to the invention, inserted in an element of the battery on the plate lugs and comprising a deflecting unit; and
FIG. 6 is a perspective view of an accumulator box comprising elementary moulds moulded onto the said box according to the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Thus, FIG. 1 shows the box 2 of an accumulator battery whose elements are limited by partitions 1, the lid of such a battery being assumed to be detached from the box. Such a box comprises, at its upper part, channels 30, each of these being common to two adjacent elements of the battery, with the exception of the end channels 30' used for forming, more particularly, the end terminals. Such channels are moulded onto the box itself, made of plastic material such as polypropylene or a copolymer of ethylene and propylene, actually implementing any appropriate shaping technique.
Inasmuch as concerns the channels 30, they comprise a flat bottom 6 arranged between two rims 7 and 8, the said bottom being provided with rectangular openings 9 having a cross-section substantially equal to that of the plate lugs 10. Moreover, the openings 9 can also comprise means (not shown) such as chamfers ensuring the guiding of the plate lugs when they are inserted. Of course, each channel has the plate lugs of an element of given polarity, as well as the plate lugs of the adjacent element of opposite polarity fitted to it.
The forming of the connections is effected in the following manner:
The box 2 being assumed to be in an upturned position, the plate lugs 10 are inserted in the openings 9 of the channels 30. The welding of the bottom 31 of the box onto the box itself is then effected, and the latter is up-turned so that it assumes the position illustrated in FIG. 1. The melting of the plate lugs 10 can then be effected, such an operation being carried out, for example, either by means of a blow-pipe or by means of a heating rod, or by implementing turns through which a high-frequency current flows. Preferably, the plate lug assembly comprises a sufficient quantity of lead for producing, after melting and cooling, the rod for connecting elements together. Of course, such a melting can be produced by casting lead in the channels, in a quantity corresponding to the dimensions of the connections to be made.
The last operation consists in welding the lid onto the box 2, such an operation being, to great advantage, and very easily, effected by thermo-welding, the upper faces of the channels, of the box walls, as well as of the partitions, being arranged in a same plane.
FIG. 2 shows a self-contained elementary mould having a flat bottom 40 in its assembly, and intended for surrounding the plate lugs of an accumulator element. The mould comprises two channels 42 and 43 provided with openings 9 having a cross-section which, firstly, is equal to those of the plate lugs, then tapering downwards in the shape of a truncated pyramid having a rectangular base. The mould comprises, at its central portion, an electrolyte level indicator 44. Such a mould may be made of a suitable plastic material, implementing any appropriate shaping technique.
FIG. 3 shows such an elementary mould 40 inserted in an accumulator element, limited, in that figure, by the walls of the box 2 and resting laterally against these walls and likewise against the element separating partition 1 (FIG. 4), with the mould 40 resting, moreover, on the separators 45. It can be seen, in FIG. 3, that the lugs 46 of the positive plates 47, for example, are fitted into the openings 9 made in the bottom of the channel 42, whereas the lugs 48 of the negative plates 49 are fitted into the openings 9 of the channel 43. FIG. 3 also shows skirts 11 providing guiding means for the plate lugs when they are inserted in the openings 9.
FIG. 4 shows, in a sectional view along the line I--I of FIG. 3, such an arrangement of the mould 40 on the lugs 46 of the positive plates 47. Moreover, FIG. 4 shows an orifice 50 formed in the accumulator element separation partition 1 in which a connection rod 51 has been formed by welding two tabs 52 together, a seal 53 being, to great advantage, inserted between the rod 51 and the orifice 50.
FIG. 5 shows that the elementary mould referenced 40' in this case can rest on the lateral rims 54 arranged on the lugs 46 and 48 of the positive plate 47 and negative plate 49, respectively. Likewise, ribs (not shown) can be provided on the inner face of the partitions of the element and of the box, and can use the mould 40 or 40' as a resting member.
Moreover, FIG. 5 shows that the mould 40' comprises, at its central portion, a deflector 55 which serves to prevent any splashing of electrolyte towards the upper part of the accumulator.
With further reference to FIG. 4, as previously mentioned, the connections between the plates of one element and the plates of an adjacent element are formed by melting the lugs 46, 48 of both positive and negative plates, such melting being effected either by means of a blow-pipe or a heating rod, or by casting lead in the channels 42 and 43 of the moulds 40 or 40'; or by means of turns through which a high-frequency current flows.
Thus, after the solidifying of the lead, the rods 15 and 16 in two neighboring elements are interconnected by means of the previously welded tabs 52, and connected by their lower portion to the rods, such connection being effected at the same time as that of the plate lugs.
It is also possible to connect the rods 15 and 16 together by direct moulding of the lead coming from the melting, through one or several orifices provided in the element separating partition, the tabs 52 not being used in this case, of course.
It has been assumed, in the above, that the elementary moulds 40, 40' were self-contained and fitted to the plate lugs of each element manually, the plates being previously arranged in the box after the bottom has been welded on the latter.
Of course, as shown in FIG. 6, it is possible to produce a box 2 comprising, for each element, an elementary mould 41, the assembly forming one moulded piece. In this case, it being assumed that the box 2 is in the up-turned position, the plate lugs are inserted in the channels 42 and 43 of the moulds 41, then the bottom 31 is welded onto the box 2 itself and the latter is up-turned. The melting of the plate lugs can then be effected as previously described.
In any case, the last operation consists in welding the cover onto the box 2, such an operation being, to great advantage, and easily, effected by thermo-welding.
The invention can be implemented in all types of accumulator batteries.
It must be understood that the invention is in no way limited to the embodiments described and illustrated, which have been given merely by way of examples. More particularly, without going beyond the scope of the invention, details may be modified, certain arrangements may be changed or certain means may be replaced by equivalent means. | The method comprises the steps of inserting plate lugs in the openings made in the bottom of at least one elementary mould, connecting together the plate lugs by rods formed by melting lead, and making the connection between the rods associated with plates of opposite polarities of two adjacent elements of the accumulator; the said elementary mould comprising a channel common to two adjacent elements of the accumulator. A varied version of an embodiment consists in implementing an elementary mould comprising two channels, each of them having the plate lugs of same polarity fitted in them. The invention is for use in the accumulator industry. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority to U.S. Provisional Patent Application No. 61/757,996, filed Jan. 29, 2013, and U.S. Provisional Patent Application No. 61/785,661, filed Mar. 14, 2013, the contents of which are hereby incorporated in their entirety.
BACKGROUND
The present disclosure relates to metal pistons used in internal combustion engines fueled by gasoline, diesel, alcohol or any other combustible fuel. Internal combustion engine pistons are usually composed of two elements; a skirt and crown. The crown may have a plurality of circumferentially extending lands spaced from a top of the land toward the piston skirt with a groove disposed between adjacent lands for receiving a piston ring. Therefore, pistons have a series of alternating lands and grooves fabricated into the crown of the piston. In some piston examples the skirt and crown are joined by a mechanical method, e.g. welding. Other examples cast or machine the pistons as a one piece skirt and crown.
In operation, a piston is received within a mating cylinder or liner of an internal combustion engine. A lubricant such as oil minimizes friction as the piston moves up and down within the cylinder, portions of the piston (e.g., the piston rings) coming into sliding contact with a cylinder wall surface.
In reality, however, during engine operation, pistons are subjected to lateral and rotational forces as they move up and down vertically within a cylinder, causing the pistons to move in an eccentric motion within the cylinder or liner of the internal combustion engine. The eccentric motion takes the piston out of the desired straight vertical path within the cylinder or liner. The off center piston alignment may cause portions of the skirt, piston rings and lands to scrape the lubricating oil off of the cylinder wall, respectively breaking through of the oil film forcing metal to metal contact.
It is known to have a land adjacent to an uppermost land, a so-called second land, and the skirt provide the vertical guidance for the piston in its mating cylinder during engine operation. In previous piston embodiments where there are multiple lands, the second land has a greater axial extent (e.g., is taller) than the other lands positioned below it (e.g. intermediate and bottom lands). Moreover, at most there is only a minimal oil film between the second land and the cylinder wall or liner during engine operation with limited lubrication and hence limited damping of the rocking motion of the reciprocating piston within the cylinder.
An approach to introduce a guidance land spaced away from the heat of combustion such as the bottom land has been developed to significantly dampen the kinetic forces that cause the eccentric and otherwise erratic piston movement within a mating cylinder during engine operation. Therefore, lubricant such as in the form of an oil film remains intact on the cylinder or liner wall. Metal to metal contact and wear, piston power loss through undesired frictional contact, and possible temperature spikes resulting from enhanced frictional contact are all reduced.
Reducing the lateral and rotational motion of the piston also reduces the noise generated by the phenomenon known as piston slap. Limiting unnecessary, detrimental movement and frictional contact of engine pistons also increases engine efficiency. The present disclosure combines several modifications to the piston crown and skirt, thereby resulting in greatly improved engine performance and efficiency.
SUMMARY
According to an exemplary illustration, there is provided a piston for use in an internal combustion engine. The piston has a central piston axis and three circumferentially recessed grooves machined into the piston. Between each groove is a circumferentially raised land that is cast into the piston. More specifically, a land positioned away from the heat of combustion such as the bottom land has a greater axial extent (e.g., is taller) than all but possibly the uppermost land (e.g., having a greater extent than the second land and an intermediate land). The increased axial extent or height of this land gives the piston increased operational performance characteristics. The piston skirt in this exemplary illustration may be shorter in height or axial extent as compared to previously known pistons. A shorter piston skirt axial extent advantageously lowers the center of gravity of the piston. A lower center of gravity increases the stability of the piston within the cylinder with regards to eccentric movement such as the contributing aspects of both lateral and rotational movement within the cylinder or liner during engine operation, particularly if the compression height (CH) is short (e.g., approximately 40 to 60% of the piston diameter)
Another exemplary illustration uses the bottom land as a component to limit both lateral and rotational movement of the piston during engine operation. In current piston constructions the land positioned below the uppermost land (e.g., the second land) is used for piston guidance. By moving the guidance land feature to a land further away from the heat of combustion such as the bottom land, the distance from the source of heat in the combustion chamber increases. The bottom land of the piston is exposed to less heat than the second land. The closer to the combustion chamber a point on the piston is, the hotter the temperature is at that point. The cooler the temperature of the land, the amount of thermal expansion seen by the land will be less. Less thermal expansion means a better control of the clearance between the piston and its mating surface since there is a reduced tolerance required to account for metal expansion because of heat. It becomes practical to reduce the clearance between the bottom land and the mating surface of the cylinder wall or liner and minimize undesired eccentric movement.
Another exemplary effect using the bottom land guidance is the hydrodynamic aspect where the oil control ring (OCR) located right above the guidance land scrapes the remaining oil on the cylinder wall or liner directly into the gap between bottom land and mating cylinder surface (e.g., liner). This oil cushion prevents asperity contact and therefore improves friction.
BRIEF DESCRIPTION OF THE DRAWINGS
Referring now to the drawings, exemplary illustrations are shown in detail. Although the drawings represent representative examples, the drawings are not necessarily to scale and certain features may be exaggerated to better illustrate and explain an innovative aspect of an illustrative example. Further, the exemplary illustrations described herein are not intended to be exhaustive or otherwise limiting or restricting to the precise form and configuration shown in the drawings and disclosed in the following detailed description. Exemplary illustrations are described in detail by referring to the drawings as follows:
FIG. 1 is a cross-sectional isometric side view of a typical prior art piston for an internal combustion engine where the fourth land has a smaller axial extent relative to the second land from the top;
FIG. 2 is a cross-sectional isometric side view of a piston according to an exemplary implementation where the fourth land has a greater axial extent relative to the second land and the piston skirt has a decreased axial extent as compared to the piston skirt of FIG. 1 ; and
FIG. 3 is a flow chart illustrating a method of assembling the piston of FIG. 2 .
DETAILED DESCRIPTION
The various features of the exemplary approaches illustrated and described with reference to any one of the figures may be combined with features illustrated in one or more other figures, as it will be understood that alternative illustrations that may not be explicitly illustrated or described may be able to be produced. The combinations of features illustrated provide representative approaches for typical applications. However, various combinations and modifications of the features consistent with the teachings of the present disclosure may be desired for particular applications or implementations. The representative illustrations below relate generally to a four-stroke, multi-cylinder, direct-injected, spark-ignition internal combustion engine. Artisans may recognize similar applications or implementations with other engine/vehicle technologies and configurations.
FIG. 1 is an isometric drawing of the side view of a prior art piston 100 without the advantages of the present disclosure. A piston 100 may include a piston crown 102 and a piston skirt 104 that may be fixed or otherwise connected with the crown (e.g., by way of a welding or casting). The crown 102 may include piston ring grooves 106 and related lands 108 extending circumferentially with two lands defining each groove 106 . Additionally, the crown 102 may include a combustion bowl 110 and a cooling gallery 112 . The piston skirt 104 generally supports the crown 102 during engine operation, e.g., by interfacing with surfaces of an engine bore or cylinder (not shown) during reciprocal motion. For instance, known skirts 104 may have an elongated outer surface 114 that generally defines a circular outer shape about at least a portion of a perimeter of the piston 100 . The outer surface 114 may generally correspond to the engine bore or cavity surfaces, which may be generally cylindrical. Known pistons 100 with elongated piston skirts 104 have an increased center of gravity, ultimately leading to increases in lateral motion during reciprocation. As such, the piston skirt 104 , and the piston 100 as a whole, is more susceptible to eccentric motion which may cause scuffing, increased friction, and reduced engine efficiency. The skirt 104 may additionally include piston pin bosses 116 extending downward from the skirt 104 . The piston pin bosses 116 may generally be formed with an aperture 118 configured to receive a piston pin (not shown). For instance, a piston pin may be inserted through the aperture 118 in the piston pin bosses 116 , thereby generally securing the skirt 104 to a connecting rod (not shown). The pin bosses 116 may generally define an open area between the pin bosses, e.g., for receiving the connecting rod.
FIG. 1 shows that lands 3 and 4 are smaller in the form of an axial extent (e.g., vertical height) than a second land 2 positioned between an uppermost land 1 of the piston and intermediate land 3 . This is a typical configuration of a piston 100 . However, known designs such as the piston illustrated in FIG. 1 are vulnerable to eccentric motion within the engine cylinder causing the skirt 104 and lands 108 to come into contact with the cylinder wall thereby leading to detrimental scuffing.
FIG. 2 is a cross-sectional isometric side illustration of a piston 200 incorporating the advantages of the present disclosure. The piston 200 may include many components illustrated in FIG. 1 , including but not limited to a crown 202 , skirt 204 , combustion bowl 210 , cooling gallery 212 , pin bores 216 , and aperture 218 . The piston crown 202 and skirt 204 may be formed of a heat-resistant metal, such as steel. According to one example, the skirt 204 may generally have an axially extent shorter or less than the axial extent of known designs, such as the skirt 104 illustrated in FIG. 1 . Consequently, the skirt 204 according to the present disclosure with a decreased axial extent lowers the center of gravity of the piston 200 . A lower center of gravity increases the stability of the piston 200 within the engine cylinder with regards to lateral movement during reciprocating motion, thereby reducing detrimental noise, vibration, and harshness (NVH) during engine operation and consequently prolonging the working life of the piston 200 .
Moreover, the piston 200 has a plurality of circumferentially extending lands cast into the piston crown 202 . The plurality of lands may include a second land 7 positioned between an uppermost land 6 and an intermediate land 8 . In turn intermediate land 8 is positioned between second land 7 and a bottom land 9 . Bottom land 9 has a greater axial extent (e.g., vertical height) than its counterpart land 4 in FIG. 1 . Land 9 may likewise have a greater axial extent than lands 7 and 8 . Additionally or alternatively, bottom land 9 may have a greater axial extent than lands 2 and 3 in prior art FIG. 1 . According to one example, top land 6 has a greater axial extent than bottom land 9 . The top or first land, being closest to the combustion bowl 210 , generally has the greatest axial extent relative to the second, third, and fourth land, as the first land has to compensate for the large combustion force and high temperatures associated with engine operation. However, according to another example, bottom land 9 may have a greater axial extent than top land 6 if operating conditions so permit. That is, the axial extent of the uppermost land may depend at least in part on fuel type (e.g., the combustion force and temperature), and/or load amounts. Accordingly, the engine performance characteristics may permit a top land 6 with a smaller than normal axial extent, in which the bottom land 9 may include a greater axial extent than the top land 6 .
According to an illustrative implementation, the piston 200 may be machined or cast to have a concave combustion bowl 210 located on the top of the piston 200 . The bowl 210 can be described geometrically as a sectioned off portion of a sphere by intersection with a plane. The concave combustion bowl 210 is symmetrically arranged on the piston top such that a center of the bowl 210 is roughly coincident with a longitudinal axis A of piston 200 .
Still referring to FIG. 2 , the piston crown 202 includes cast or machined annular grooves 14 , 15 & 16 provided about the perimeter or periphery of the crown 202 , adjacent to the cooling gallery 212 . The annular grooves 14 , 15 , and 16 may be configured to accommodate the piston rings (not shown). The grooves 14 , 15 , 16 separate and are defined by adjacent lands.
During engine operation, the piston 200 is attached to a connecting rod (not shown) and reciprocates upwardly and downwardly axially in an associated cylinder or liner. The cylinder or liner is covered with a film of oil on its outer exposed surface by an oil supply and an oil control ring carried in the lowermost piston ring groove 16 disposed between lands 8 and 9 . During normal engine operation, reciprocation generates lateral and rotational forces; these two forces impart a non-uniform, irregular or eccentric piston motion within the cylinder or liner. In previously known operation, the eccentric motion of the piston may cause the piston lands and/or skirt to be misaligned with respect to the cylinder or liner wall. The misaligned lands shear off/break through the lubricating oil film otherwise present on the cylinder or liner wall. When the oil film is removed, metal to metal contact and frictional forces in the cylinder-piston system increases, power is lost and engine life may be significantly reduced, resulting in increased risk of scuffing.
The present disclosure minimizes the generation of undesirable and harmful eccentric motions of the piston. In the present exemplary illustration as shown in FIG. 2 , the height or axial extent of the second land 7 is reduced as compared to its corresponding counterpart land 2 in the known art represented in FIG. 1 . The axial extent of the bottom land 9 in FIG. 2 is increased and is therefore greater than known bottom lands 4 . Additionally, the overall axial extent or length of the piston skirt 204 is shortened as compared to skirt 104 .
The illustrative piston 200 identifies a direct correlation between: the increased height of the bottom land or guide land 9 , a reduced height of the piston skirt 204 and the lowering of the piston's center of gravity, and the elimination of the undesirable lateral and rotational forces present in previous piston implementations. The exemplary piston 200 described notes that the distance defined by the bottom land 9 to be a specific interval of the overall axial extent of crown 202 (e.g., an axial extent of about two (2) to seventeen (17) percent the diameter of the crown 202 ) to eliminate the harmful lateral and rotational forces. The overall axial extent of skirt 204 is also reduced as compared to the known art.
As illustrated in prior art FIG. 1 , pistons 100 are produced with relatively long in the form of axial extent piston skirts 104 and long in the form of axial extent second land 2 height as compared to the intermediate 3 and bottom 4 piston lands. This known configuration of piston lands (e.g., second land 2 with a greater axial extent than the fourth land 4 ) allows the piston 100 to tilt relative to the associated cylinder or liner during engine operation. Parts of the tilted piston scrape the film of lubricating oil off of the cylinder or liner wall exposing bare metal. In the illustrative embodiment detailed in FIG. 2 , increasing the axial size of a land located a greater distance from the heat of combustion, such as the bottom land 9 , reducing the height of the second land 7 , and decreasing the axial length of the piston skirt 204 , consequently reduces and otherwise minimizes the lateral and rotational motion of the piston. Therefore, the lubricating oil film is unbroken and the harmful metal to metal frictional contact is eliminated.
During normal engine operation, a plentiful, uninterrupted source of lubricating oil is available in accordance with the teachings set forth above with respect to FIG. 2 as compared to the teaching of FIG. 1 . As noted above, when there is little to no lubrication between a piston and its mating cylinder wall or liner (e.g., the lack of an oil film between the second land and its mating cylinder surface), reduced oil volume and resulting lubrication availability leads to scuffing of the cylinder wall and increased metal to metal contact of the piston to cylinder wall at locations such as that illustrated by land 2 of FIG. 1 .
Having a marginal oil film between the second lands and the associated cylinder or liner increases the noise generated by the piston during reciprocation. Another issue relates to blow-by, resulting from undesired clearance between a piston and its mating cylinder wall or liner surface, reducing engine efficiency while also increasing oil consumption.
Therefore, a piston 200 according to the present disclosure including a guide land (e.g., land 9 ) that is located axially away from the heat of combustion (e.g., the combustion bowl 210 ) along the outer periphery of the crown 202 reduces the thermal expansion of the guide land since the maximum temperature of that portion of the crown is lower than for the lands closer to the uppermost portion of the piston crown 202 where the combustion bowl 210 is located. In view of the foregoing, it is possible to have tighter tolerances since the radial expansion of the guide land 9 is reduced as compared to lands at a higher temperature. By having tighter tolerances the cold installation clearance between the piston and its mating cylinder or liner surface may be reduced. As such, a land having an increased axial extent as compared to other lands closer to the combustion bowl, but positioned downwardly of the uppermost land, presents significant advantages. The piston surface pressure is redistributed (with lower asperity contact and higher hydro contact because of enhanced lubrication as compared to the prior approaches) that may be quantified by a reduction in friction power loss. Additionally, piston kinetic energy is reduced, which may be quantified by a reduction in mechanical power loss.
Another exemplary effect using bottom land 9 guidance is the hydrodynamic aspect where the oil control ring (OCR) located right above the guide land scrapes the remaining oil on the cylinder wall or liner directly into the gap between the bottom land 9 and mating surface (e.g., liner). This oil cushion prevents asperity contact and therefore reduces friction, improving performance.
The overall reduction in the axial height of the piston 200 because of a desired positioning of a land best able to minimize eccentric motion, in combination with a potential reduced height of the associated skirt as noted above, either individually or together help contribute to the reduction of energy losses. The disclosed enhancements reduce eccentric motion of the type discussed above.
Moreover, as previously noted, additional advantages are realized by minimizing eccentric motion. For example, (1) engine blow-by is reduced, (2) oil consumption is reduced, (3) cylinder wall or liner cavitation occurrences are minimized, and (4) issues related to engine noise, vibration, and harshness (NVH) are also reduced.
It is also envisioned that by having a land such as the bottom land 9 with an increased axial extent, the overall size of a cooling gallery 212 including a region positioned between the skirt 204 and the bottom land 9 may be enhanced as compared to known pistons, increasing cooling channel volume, and thereby intended to increase cooling channel efficiency. The cooling gallery 212 helps to facilitate the placement of oil to the contact surfaces represented by the piston and the cylinder wall or liner to enhance hydrodynamic lubrication as the piston 200 strokes up and down.
According to one example, the uppermost land may be known as L 1 . The next land (i.e., the second land) may be known as L 2 . The next land down (i.e., the intermediate land) may be known as L 3 . Finally, the bottom land may be known as L 4 . In the current illustrative approach according to FIG. 2 , L 4 (land 9 ) is used for piston guidance within the cylinder as opposed to typical embodiments that use L 2 (land 2 of the prior art from FIG. 1 ) for piston guidance. L 4 (land 9 ) is located farther away from the combustion chamber 210 as compared to the other lands and therefore is exposed to a lower operating temperature than L 2 (land 2 of the prior art from FIG. 1 ). In typical approaches radial thermal expansion of L 2 (land 2 ) is greater than L 4 (land 9 ) due to the proximity of L 2 (land 2 ) to the combustion chamber 210 heat. L 4 (land 9 ) expands radially less than L 2 (land 2 ). Therefore, there is less friction of L 4 (land 9 ) in engagement with its mating cylinder wall or liner. In the current illustrative implementation, L 4 (land 9 ) has an enhanced large surface area which has a minimized clearance (0 um to 60 um) with its mating cylinder wall or liner resulting in the benefits discussed above.
In one illustrative approach, land 9 (L 4 ) may have an axial extent of between approximately two (2) to seventeen (17) percent of the overall piston 200 and/or piston crown 202 diameter. The piston skirt height or axial extent may be between approximately ten (10) to fifty (50) percent of the overall piston 200 and/or piston crown 202 diameter. In an exemplary approach the axial extent of an “opening” 220 representing a portion of cooling gallery 212 positioned between the top of skirt 204 and the bottom land 9 may also have a dimension of approximately ten (10) to fifty (50) percent of the piston 200 and/or piston crown 202 diameter.
Additionally, land 9 (L 4 ) may be coated with one of several friction reducing materials to wear resistance. These coatings can be but are not limited to: TiN, CrC, CrN or Cr. The coatings may also be known by such names as Grafal™ and Evoglide™. The coatings can be applied in a variety of ways not limited to: thermal spray, physical vapor deposition or electrochemical plating.
FIG. 3 illustrates a method 300 of configuring a piston 200 . At block 305 , the piston crown 202 and piston skirt 204 may be provided. The piston 200 may have a combustion bowl 210 machined or cast into the crown 204 . The piston crown 202 and skirt 204 may define a circumferentially extending cooling gallery 212 about the perimeter of the piston 200 . The piston skirt 204 may include a pair of oppositely disposed pin bosses 216 defining a piston pin bore or aperture 218 . The skirt 204 may be defined by a skirt axial extent (e.g., height) which may be less than that of a typical piston skirt (e.g., as compared to the piston skirt 104 illustrated in FIG. 1 ). The exemplary skirt axial extent may be no more than fifty (50) percent of a diameter of the piston 200 or piston crown 202 . Accordingly, the skirt axial extent or height, and consequently the overall height of the piston 200 , is reduced thereby lowering the center of gravity of the piston 200 . Consequently, stability of the piston is increased as it moves within the engine cylinder and eccentric motion is reduced.
At block 310 , a plurality of lands may be formed in the piston crown 202 . The lands 6 , 7 , 8 , and 9 may be separated by a groove 14 , 15 , and 16 , respectively, that is cast or machined into the crown 202 and which is defined between circumferentially raised adjacent lands. According to one example, the plurality of lands may include a first land having a first axial extent, a second land having a second axial extent, and a third land having a third axial extent. The first land may be near the combustion area (e.g., the combustion bowl 210 ), the second land may be positioned intermediate the first and third land, and the third land may be away from the region of combustion with respect to the first land. For instance, the first land may be the top or uppermost land 6 , the second land may be land 7 , and the third land may be the bottom land 9 , as illustrated in FIG. 2 . The third land may be configured as the guide land having a greater axial extent than the intermediate second land. The axial extent of the third land may be about two (2) to seventeen (17) percent of a diameter of the piston crown 202 . By moving the guide land (e.g., the third land) away from the combustion area, the land is exposed to less heat and therefore the thermal expansion seen be the land is decreased. Consequently, less thermal expansion may lead to less oil removed from the engine cylinder walls by way of the land.
According to another example, the piston crown may be composed of four lands (e.g., land 6 , 7 , 8 , and 9 ), numbered sequentially from the top or uppermost part of the crown down towards the direction of the skirt. Pursuant to one implementation, the fourth or bottom land 9 may have a greater axial extent than the second and third lands 7 , 8 . The first or uppermost land 6 , however, may have the greatest axial extent in relation to the second 7 , third 8 , and fourth land 9 in order to compensate for the large combustion forces and high temperatures created at the top of the piston (e.g., in the region of the combustion bowl) during engine operation. However, as mentioned above, depending on the performance characteristics of the engine (e.g., combustion force, temperature, load), the bottom guide land 9 may have a greater axial extent than the top or uppermost land 6 .
At block 315 , the piston crown 202 and skirt 204 may be adjoined or otherwise secured together to form the piston 200 . For example, the piston crown 202 and skirt 204 may be joined by a mechanical process, such as welding, brazing, soldering, etc. Conversely, the piston 200 may be cast or machined as a one piece crown 202 and skirt 204 .
At block 320 , the guide land (e.g., land 9 ) may be coated with a friction reducing layer or surface to decrease friction and/or wear resistance. Exemplary coatings may include, but are not limited to, TiN, CrC, CrN, or Cr. The coating may be applied via a variety of processes, including thermal spray, physical vapor deposition, or electrochemical plating.
Accordingly, while illustrative implementations of the present disclosure have been shown and described, it is obvious that changes and modifications may be made thereunto without departing from the spirit and scope of the disclosure. For example, in some approaches, a land positioned upwardly of the bottom land, but located sufficiently away from the combustion chamber may still have sufficiently low thermal expansion in operation to have the enhanced axial extent.
With regard to the processes, systems, methods, etc. described herein, it should be understood that, although the steps of such processes, etc. have been described as occurring according to a certain ordered sequence, such processes could be practiced with the described steps performed in an order other than the order described herein. It further should be understood that certain steps could be performed simultaneously, that other steps could be added, or that certain steps described herein could be omitted. In other words, the descriptions of processes herein are provided for the purpose of illustrating certain embodiments, and should in no way be construed so as to limit the claimed invention.
Accordingly, it is to be understood that the above description is intended to be illustrative and not restrictive. Many implementations and applications other than the examples provided would be apparent upon reading the above description. It is anticipated and intended that future developments will occur in the arts discussed herein, and that the disclosed systems and methods will be incorporated into such future implementations. In sum, it should be understood that the invention is capable of modification and variation.
All terms used in the claims are intended to be given their broadest reasonable constructions and their ordinary meanings as understood by those skilled in the art unless an explicit indication to the contrary in made herein. In particular, use of the singular articles such as “a,” “the,” “said,” etc. should be read to recite one or more of the indicated elements unless a claim recites an explicit limitation to the contrary. | Steel pistons used in many internal combustion engines are generally composed of a skirt and a crown. The skirt's function is to reduce the lateral and rotational movement of the piston in the cylinder while the engine is in operation. Lateral and rotational frictional forces imparted to a piston during engine operation cause the piston to scrape off the lubricating oil film present on the cylinder wall. The reduced oil film thickness increases piston and cylinder wall wear due to metal to metal contact. The subsequent metal to metal contact produces a phenomenon called scuffing. This disclosure incorporates several design modifications to the piston and results in a significant reduction of the lateral and rotational motion of the piston during engine operation. The reduction of piston motion reduces the amount of oil film removed from the cylinder wall and increases lubrication efficiency. The Increased lubrication efficiency realized reduces frictional wear power loss and scuffing. | 5 |
FIELD OF THE INVENTION
The present invention relates generally to home automation control functions. More specifically, the invention relates to ganged positioning of window coverings and analogous automated control processes.
BACKGROUND OF THE INVENTION
Home automation control systems have established a growing industry and can be expected to persist as controller devices, programming methods, function concepts, and communication technologies advance in capability and decline in incremental cost to market. Particular functions continue to extend capability of existing products, adding and refining convenience, security, safety, and enjoyment features.
Among potential beneficial improvements in home automation functionality are apparatus and methods capable of providing substantially simultaneous operation of multiple motor-driven devices. Known devices provide incomplete realization of such functionality. For example, barrier positioners that are motorized, can exhibit varying condition of operation as a consequence of manufacturing tolerances, age, wear, bearing condition, battery state, and other factors. A home automation controller that relies on previous designs to command several barrier positioners simultaneously to first start, then run, then stop in a uniform fashion is unlikely to perform these functions consistently over product life. The consequences of uncertain start delay, nonuniform run speed, and variable response to stop commands include uneven appearance after stopping except at ends of travel (i.e., full up and full down positions), undesirable at least in a high-end consumer product.
What is needed is an apparatus or method that can ensure highly uniform action of multiple, separately-installed actuator devices at least in a home automation environment.
SUMMARY OF THE INVENTION
The above needs are met to a large extent by apparatus and methods in accordance with the present invention, wherein multiple home automation devices can realize uniform net operation despite variability in individual actuation characteristics, through enhanced operational control.
In one embodiment, a method for operating a plurality of autonomous, processor-controlled, multi-position actuators in unison from a separate control station is presented. The method includes establishing a wireless communication network that originates with the separate control station and provides bidirectional message transfer between the separate control station and each multi-position actuator, assigning a processor-readable address to each multi-position actuator, and providing a command set for each of the plurality of multi-position actuators that includes for each command in the command set the assigned actuator address and one of a plurality of executable functions. The command set includes at least one command to realize one position value from a plurality of position values defined for the actuator, and at least one stop command. The method further includes assigning the plurality of multi-position actuators to a group, and defining a plurality of group commands, including in each group command a plurality of discrete commands to perform a like executable function, directed to the addresses of the plurality of multi-position actuators in the group.
In another embodiment, the above method is modified through the use of broadcast commands in lieu of group commands, so that the method includes providing a command set for each of the plurality of multi-position actuators that includes for each command in the command set the assigned actuator address and one of a plurality of executable functions. The command set includes at least one command to realize one position value from a plurality of position values defined for the actuator. The command set further includes at least one stop command. The method further includes defining a plurality of broadcast commands that includes for each broadcast command the broadcast address of the plurality of actuators and one of a plurality of executable functions.
In still another embodiment, an autoleveling, remotely controlled multiple window shade positioner system is presented. The system includes a plurality of motorized window shade positioners, each including a wireless radio frequency transceiver assigned to a predetermined frequency band, a command decoder, a command address comparator, a polling reply message generator, a spoolable window shade, a window shade spool drive motor, and a calibratable position detector. The system further includes a control station, including a command generator, a wireless radio frequency transceiver assigned to the frequency band of the positioner transceivers, a command generator, and a polling reply data processor.
In yet another embodiment, an autoleveling, remotely controlled multiple-value positioner system is presented. The system includes a short-range radio transceiver-based network with a separate control station that provides bidirectional message transfer between the separate control station and each of a plurality of autonomous, processor-controlled, multi-position actuators, each of which has a corresponding transceiver. Each multi-position actuator includes support for retention of a processor-readable address, with the actuator addresses non-repeating within the plurality of multi-position actuators. Each of the plurality of multi-position actuators recognizes both its retained address and a plurality of executable function codes. The set of executable function codes includes at least one code commanding translation to one position value among a plurality of position values defined for the addressed actuator. The set of executable function codes further includes at least one stop command. The plurality of multi-position actuators are assignable to a group using assignment routines in the control station. The group is commandable by the control station by any group command associated with that group, with the group command including a plurality of discrete commands addressed to the actuators in the group, to perform a like executable function.
There have 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 below 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. It is also to be understood that the phraseology and terminology employed herein, as well as in the abstract, are for the purpose of description, 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.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a single roller blind configured for remotely commanded operation in a home automation system.
FIG. 2 is a perspective view of controller devices compatible with operation of multiple roller blinds of styles such as that shown in FIG. 1 .
FIG. 3 is a first graphical representation of multiple roller blinds commanded from a common control unit, according to the prior art.
FIG. 4 is a second graphical representation of multiple roller blinds commanded from a common control unit, controlled using the processes of the present invention.
FIG. 5 is a first flow chart representing operation in accordance with the present invention.
FIG. 6 is a second flow chart representing operation in accordance with the present invention.
DETAILED DESCRIPTION
The invention will now be described with reference to the drawing figures, in which like reference numerals refer to like parts throughout. An embodiment in accordance with the present invention provides an improved barrier positioner control method for home automation, as well as apparatus in support thereof, wherein a basic scene command to a group of similar devices can compensate for variability in operation of the individual devices to present a uniform final appearance. Quantification, verification, and repeatability made possible by the present invention overcome producibility limitations intrinsic to earlier concepts.
FIG. 1 shows a roller blind 10 , also termed a shade, compatible with use as a part of a home automation system. In addition to a flexible shading panel 12 that can be spooled and unspooled to provide and remove a barrier to light, in at least the senses of blocking visual exposure and obstructing illumination, the roller blind 10 includes a roller (equivalently termed a spool) 14 around which the panel 12 is wrapped in multiple layers when not providing a light barrier, and a housing 16 , shown in part exploded, that supports the roller 14 at the ends thereof and permits attachment to a home structure. The roller blind 10 further includes a wiring provision 18 for applying electrical power for use by a controller 20 and by a motorized actuator such as an electric motor 22 , in order to actuate the roller blind 10 without physical contact by a user. In some embodiments, the wiring provision 18 and/or the controller 20 may include a battery pack 24 for use as a primary or backup power source. A weighted shade end bar 26 may apply downward force to the panel 12 . A top-of travel stop 28 may have the form of a slot as shown; a bottom-of-travel stop 30 may have the form of a simple window ledge.
The controller 20 of the apparatus of FIG. 1 may preferably support being commanded, for example, by a radio signal from a short-range transmitter or transceiver, within a finite effective working space, limited by the transmitted signal power, receive sensitivity, and characteristics of the associated antennas and the propagation environment, including an assigned frequency band of operation. Alternative command communication technologies, such as infrared or other optical transmission, ultrasonic or other acoustical transmission, utility (mains) power line signal transmission, and the like, may be preferred in other embodiments, with the understanding that technologies that support bidirectional and wireless communication may be preferred, and that realization of bidirectional data flow may introduce complexity or additional cost to some embodiments not based on well-defined wireless home automation control systems and existing channel spectra.
FIG. 2 shows enclosures for a fixed-base controller 32 and a hand-held remote 34 according to the present invention, superficially similar to many known styles of home automation controller apparatus, but incorporating functionality that makes one or the other capable of operating pluralities of the roller blinds 10 of FIG. 1 , for example, according to the present invention. User interface and system control devices such as the controller 32 and remote 34 shown include discrete, fixed-assignment push buttons 36 as user interface elements in the embodiment shown. In other embodiments, the user interface elements may include specified touch-screen areas, slide bar input values, dynamically-defined push buttons associated with display elements, combinations of functions that provide mouse- or trackball-like functionality, or other interface forms. Either a controller 32 or a remote 34 may include a display portion 38 , which may be limited to one or more lamps or to text or special symbol indication, or may provide more extensive information.
The wall-mount capability of the fixed-base controller 32 shown is peripheral to its function. Embodiments of such a controller 32 may be powered by self-contained primary or secondary batteries or through a utility (mains) source, which may be augmented at least in part by solar cells or other resources. In still other embodiments, user interface through a fixed-base controller 32 may be augmented by a personal digital assistant (PDA), a computer, or another communication unit configured to access a home automation network directly or indirectly.
In embodiments such as those shown, a broad-functionality fixed-base controller 32 may be configured to transmit commands to home automation-compatible devices such as the shades 10 shown in FIG. 1 . Where a manufacturing process, initial programming, or system setup has established an address for each shade 10 that is retained within the controller 32 , the commands may include, in at least some embodiments, such directions as “go up,” “go down,” “stop,” “report position,” “calibrate yourself,” “go to position x,” and the like for each shade 10 . The inclusion of position-related commands implies adequate precision and measuring capability within each shade 10 to execute such commands. The remote 34 may communicate with the controller 32 , or may communicate directly with home automation devices or groups thereof. A sparse display 36 and button 38 set in some embodiments of hand-held remotes 34 may dictate that a command set be structured in a particular fashion, such as assigning a single button to cycle through “start upward,” “stop,” “start downward,” and again “stop,” for a group of any size, with other functions reduced in availability through the remote 34 .
It is to be understood that the calibration and precision motion control functions referred to above may require detector functions within each shade 10 or comparable device used in an application. Such detector functions may preferably include, as components, a shaft angle transducer, such as an encoder that may be integral with the motor 22 in some embodiments, a shaft angle telemetry storage element, such as a memory location maintained by a processor portion of the controller 20 in the shade 10 , and the weighted shade end bar 26 , similar to ordinary wooden bars in spring-powered roller blinds but thicker and/or heavier in some embodiments to provide increased stabilizing downward force. The detector function may further include a shade retraction end-of-travel stop 28 , such as a slot through which the flexible shading panel 12 passes freely but which blocks the bar 26 , and a shade extension end-of-travel stop, which may be as simple as a window ledge 30 struck by the bar 26 when fully extended. Use of these styles of stops 28 , 30 may require that current applied by the controller 20 to the motor 22 be monitored with precision, so that detection of motor 22 overcurrent may be interpreted as the shading panel 12 having retracted to the retraction end-of-travel stop 28 , while motor 22 undercurrent may be interpreted as the shading panel 12 having extended to the extension end-of-travel stop 30 .
The above apparatus supports positioning a constant-length shading panel 12 with reference to a window or other panel. Further calibration may include a processor 20 function within the shade 10 , such as using a scaling algorithm to correlate the output pulse count range of an encoder (more generally, the value range of a shaft angle or other position transducer) to a realizable range of motion of the flexible shading panel 12 . Such a scaling algorithm may allow computing with some precision the absolute extent of payout, or scope, of the flexible shading panel 12 .
Scope and scaling data may be volatile in some embodiments that employ it, requiring calibrating the actuation mechanism driven by the motor 22 in the roller blinds 10 after a power initialization. Some embodiments may calibrate automatically during each initialization after power loss by driving the flexible shading panel 12 or any other movable elements of each roller blind 10 directly to, for example, a fully-retracted position, then to an opposite position, such as a fully-extended position, capturing during this process both a zero point and a range of traverse, such as a maximum encoder count, and storing in each shade 10 calibration values for a start point and range of traverse. Positioning commands may be based directly on transducer values or may be subject to scaling. It may be noted that strictly battery-powered embodiments can change in speed as a function of battery 24 condition, although contemporary high-efficiency regulators can adjust battery 24 discharge rate over a wide range of battery 24 condition in lieu of permitting variation in motor 22 speed. Certain motor designs, such as stepper motors, may detect position with considerable accuracy as a function of drive pulse count and sensing ends of travel by current/voltage phasing, for example, while obviating separate transducers.
FIG. 3 shows a prior-art compatible configuration of several shades 10 , whereof the flexible shading panels 46 , 48 can be translated as a group 40 to a different height, such as to implement a part of a “scene” as defined in applicable Z-Wave® (© Zensys® Corporation) specification documents. As illustrated in FIG. 3 , the heights of individual windows 42 , 44 may not be similar, and the result of a fixed time-of-run command directed to a group 40 , whether manual or automatic, may result in uneven extension of the respective shading panels 46 , 48 . Correction of such uneven positioning, herein termed leveling, may require a user to direct individual motion commands to the respective shades 10 .
FIG. 4 shows several shades 10 that are compatible with receiving and executing commands issued by a home automation controller 32 or 34 of FIG. 2 , and incorporating the present invention. Embodiments incorporating the present invention realize a uniform group positioning function, herein termed autoleveling, according to at least one of the positioning modes described herein. It is to be understood that the term autoleveling may refer to relative height, as in the roller blinds 10 shown in FIG. 4 , and may equally refer to relative lateral, angular, or other physical displacement, or to relative temperature, motor speed, sound level, air flow rate, etc.
In one positioning mode, a manual actuation by a user with a fixed-base controller 32 or a hand-held remote 34 commands all of the shades 10 in a group 50 to start to translate in an up or down direction. At a subsequent time, the user commands the group 50 to stop. The present invention thereupon polls the group members 52 , 54 , 56 , that is, it issues a series of position inquiries from the remote 34 or the fixed-base controller 32 to the group members 52 , 54 , 56 . Each of the group members 52 , 54 , 56 responds by transmitting a present position value based on measurements acquired as described above. The present invention compares these position values, then issues discrete commands to the respective group members 52 , 54 , 56 to further translate to one of the position values just received. The selected position value may be established according to a rule, such as by assuming that a user will preferentially halt a process when a first of the group members 52 , 54 , 56 —in effect, a leader—has reached a user-desired position. It may be observed that one or more members of the group will receive a command to translate to the position already occupied; this can be a known function for a device configured for operation in a home automation control environment, and may allow simplification of the procedure steps—the controller compares all of the devices, and, based on the commanded direction of travel, finds the most-extended or least-extended position value and commands all shades 10 to that position. In some embodiments, it may be preferred to issue commands only to the shade 10 that need to move further to reach a uniform position.
In other embodiments, scaling may be required before comparison and before command issuance in order to achieve a common height, or a preferred differential height may be commanded. For example, observing that a window and its shading panel 54 are taller (or shorter in other cases) than others in a group, it may be desired to have all of the group members 52 , 54 , 56 move together over the common part of their range, with any odd units either stopping or continuing to respective end-of-travel positions after the others have stopped. If calibration for the devices is based on end-to-end measurement, and position values are based on percentage of travel, for example, then commands can combine offset and scaling to provide a final result. Values of offset as well as origin and scaling may be computed and/or stored within each roller blind 52 , 54 , 56 , or within a controller 32 , 34 . Programming in support of assigning one or more offset values to one or more of the roller blinds 52 , 54 , 56 and management of the combined positioning instructions according to the present invention can likewise reside within each roller blind 52 , 54 , 56 , or within the fixed-base controller 32 or hand-held remote 34 .
If a group member 52 , 54 , or 56 has reached end of travel (fully extended or fully retracted) before the stop command is issued, that group member 52 , 54 , or 56 may be excluded from the comparison routine in some embodiments, such as by omitting 0% and/or 100% values from the comparison, which can ensure positioning away from one or both ends of travel by default. In other embodiments, ends of travel may be treated as regular positions.
In a second positioning mode, substantially all functionality may be equivalent to that in the first mode except that a push-and-hold operation applied to a button 36 or equivalent user interface element is required in order to cause the group 50 to continue to move, and release of the button 36 or equivalent results in a halt and the above-described after-halt position adjustment.
In a third positioning mode, a command function other than a manual user input may accomplish an equivalent position adjustment. In a first case consistent with this mode, a scene may include a brightness level in a room, detected by a photoreceptor module integrated into a home automation system, with the brightness level to be realized in part by opening roller blinds 10 part way if possible. In this case, a photoreceptor-referring command may be issued to start to change the heights of the group members 52 , 54 , 56 . When the intended light level is achieved (at a startup event for operation in this mode) or restored (after a change in available light, such as from sun motion or cloud cover, and typically after a fixed minimum time interval has passed), a preliminary halt directed by passing a threshold from the photoreceptor may be followed by the above-described polling and subsequent issuance of an adjustment command. Hysteresis in the control system and moderate uniformity in the actions of the group members 52 , 54 , 56 allow a single adjustment of position to be applied. Where system function is less well tuned, a first adjustment that exceeds the tolerance range for the photoreceptor module can trigger a second commanded positioning activity followed by a second polling and adjustment step. Readjustment of a system function such as that described in this case can occur as often as needed or at time intervals permitted by the controller 32 .
Where system limits are subject to being exceeded, such as in the above case if no amount of shade 10 repositioning can realize an intended light level, additional process stages can be appended. For example, a scene may activate interior lighting if maximum shade 10 opening fails to introduce enough light, and may further readjust or close the shades 10 . Time-of-day and seasonal factors may likewise be incorporated into such a scene calculation, for example to determine whether or when to attempt subsequent reopening of the shades 10 to provide the desired light level from natural sources. Previous knowledge, such as that interior lighting cannot reach a sunlight-keyed threshold, may be programmed into the scene to advance from the previous scene configuration, invoking a second threshold.
Similarly, the control process may be used for functions other than flexible shading panel 12 positioning: if a scene calls for temperature and/or humidity regulation to include natural climate sources, for example, then any combination of opening and closing of windows, activating of variable-speed ventilation fans, combining heating and cooling to remove moisture, extending and retracting variable-position awnings, and the like may involve polling and issuing successive commands in response to feedback to establish a desired uniformity of appearance or function.
A control system maintaining conditions in multiple rooms in a home, school, office building, or the like may monitor one or more criteria for each of the rooms, operating available variable-value actuators to regulate each independently, particularly in view of changes in outdoor conditions over the course of a day or a season. For example, using at least one thermostat-style temperature sensor, in a room having a plurality of multi-speed or variable-speed ceiling fans with state feedback, the control system can set the fans to blow up or down at a common rate, adjust the rate as temperature shifts over a day, coordinate fan function with window and shade function, and the like. Where fan speed is substantially continuously variable, such as over a finely stepped digital command range, realized speed for each fan may differ from a command-signal speed reference, so that a compensation table or a calibration function may be required for each fan in order to regulate all fans within a group to an effectively uniform speed and/or acoustic signature.
In another exemplary embodiment, closer to the basic application strategy, a window covering system may include a row of upward-raised shades and a row of downward-lowered shades, with the spools of the respective rows vertically proximal. In such an arrangement, users may view from lower windows, or may admit light through upper windows while maintaining privacy by keeping the lower row of shades fully closed. Adjusting the shades in each row to a uniform appearance may be performed automatically using the invention. By extension, any number of groups of actuators may be autoleveled or otherwise reconciled to a uniform state within each group using the invention.
FIG. 5 is a flowchart 100 showing representative manually-activated process flow for an embodiment of the present invention. After initialization 102 , a first motion command 104 from a user-operated control device orders that a previously-defined group of N distinct elements begin 106 and continue to move in a chosen direction—i.e., apply power to the respective motors of the group members in such a way as to cause the respective window shades of the group in the embodiment shown to all move up or down as determined by an input external to the command. As previously addressed, such a group may be of any size. Processes for identifying or defining such a group are addressed in references such as U.S. patent application Ser. No. 12/191,912, filed Aug. 14, 2008, and incorporated herein by reference in its entirety.
After an indeterminate period, as decided by and under the control of a user, a second motion command 108 orders that all N group members stop 110 the motion previously initiated. In the embodiment shown, the motion begin process 106 and the motion stop process 110 take the form of commands issued by the controller 32 to the individual, autonomous members of the group, each of which is a transceiver-equipped roller blind 10 . Since starting each motor in response to a command may take an uncertain amount of time and begins an open-ended process, confirmation of starting may not be critical, and is not shown in this embodiment. Completion of the stopping operation, however, determines when the next process may begin. As a consequence, the embodiment monitors group stopping 112 , by a process represented as a series of tight loops blocking execution of subsequent processes.
It is to be understood that numerous alternative programming procedures are equivalent to the series of tight loops 112 shown, so that the process should be viewed as representative and not limiting. For example, the group members, roller blinds 10 , may be configured to transmit an echo in response to each received command and to report each status change, such as “started moving up” or “finished stopping”, so that replies from all members arrive at the controller 32 for each start command, each startup event, each stop command, and each stop event. The controller 32 may then filter these messages for the ones needed in realizing the present invention. If the controller 32 functionality for the present invention is interrupt driven, then the process of waiting for all group member stop reports may be intrinsic, albeit operationally equivalent to the tight loops 112 shown. Such a routine can confirm group members that report and can perform further tests such as timing errors during execution. In still other embodiments, a group address may be definable, allowing the controller 32 to broadcast a single command for each of starting 104 and stopping 108 in lieu of the multiple commands shown. System design for classes of commands may further determine whether outgoing group commands result in confirmations, as well as communication protocols such as collision control.
The embodiment may assume by default that each such group member is operational. The controller 32 can include functionality to assess group member state of health, a process substantially independent of the present invention.
Following confirmation of stopping 112 , the process in the embodiment shown includes polling 114 to determine the current position of each group member. As indicated above, alternative embodiments may be realized; in some of these, position reporting may be automatic as a part of a status change report message, so that separate polling 114 for position can be limited to data loss or timeout conditions. Thus the process shown is not to be viewed as limiting.
Once the accumulated group element position data is available to the controller 32 , the extreme among the group is identified 116 by a process identified herein as sorting. If each group member is a positioner, as characterized in the embodiment shown, and includes a measuring capability, such as with an electric motor 22 coupled to both the flexible shading panel 12 and a rotary encoder providing a direction-flagged series of pulses corresponding to panel extension, then the motor controller 20 may hold a datum that has a maximum value when the panel 12 is fully extended and a minimum value when the panel 12 is fully retracted, for example. In such embodiments, the sort function 116 may be as simple as configuring the controller 32 to receive successive poll 114 results and retain only the desired extreme value, either the lowest value, representing the most retracted shading panel 12 , or the highest value, representing the most extended shading panel 12 , as desired for the function.
Following determination of the “most advanced” value among the group members, which is defined as the preferred value by the default logic indicated, the controller 32 can transmit individual fixed-destination motion commands 118 to the respective group members, which are configurable to move autonomously to the indicated position. Zero-motion commands, that is, commands to group members that direct them to locations currently occupied, may be assumed to be defined and harmless to the affected group members, so that the controller 32 need not screen previous position reports to avoid such transmissions. Following issuance of the fixed-destination motion commands 118 , the user-controlled auto leveling group opening routine of FIG. 5 has reached termination 120 .
It is to be observed that an extent of time to execute the described position alignment depends on the processing speed of the electronic devices involved and on characteristics of the communication system employed. In substantially all anticipated systems, each such function is likely to be performed in a small fraction of a second, so that a perception of a pause between panel 12 stopping and panel 12 restarting following user stop input 112 is likely to be minimally perceptible to a user, although readily detectable by suitable instrumentation. Time to reach final alignment depends on properties of the window shade 10 drive systems, including panel 12 inertia (angular momentum), extension distance (off-balance weight), motor power, extent of discrepancy between group member positions, and details of the start/stop algorithm used by the respective shade controllers 20 in an embodiment, as well as state of battery charge in battery-powered equipment.
FIG. 6 illustrates in flow chart 130 form a second embodiment of the present invention, supporting broadcast communication in addition to or in lieu of defining groups and addressing the individual elements of the groups. The controller 32 and/or hand-held remote 34 supports a broadcast mode, wherein commands are recognized by individuals configured as members of a broadcast group. Following initialization 132 , a single broadcast command 134 directs all group devices to begin translation in a chosen direction 136 . The user subsequently commands the group to stop 138 at a selected location. In the embodiment shown, interrupt based software architecture is employed, so following the broadcast 140 of the stop command, the system waits for interrupts from all group members 142 . Each interrupt 144 restarts a service routine; once all group members are accounted for 146 , the controller polls for a first group member's position 148 , stores this as the default target value 150 , then continues to poll each remaining group member 152 , replacing the current target value 156 with the newly acquired one 154 if it represents greater travel. Once all values are acquired and this de facto sort is completed, the residual value is the target. This target value is thereupon broadcast to all group members 158 . At this juncture, execution is complete 160 for at least some embodiments. In other embodiments, status reports may be provided by the group members as a default action. In these embodiments, a final verification and/or position adjustment may be performed prior to completion 160 , functionally equivalent to that described above for FIG. 5 at steps 114 , 116 , and 118 .
Position sensor technologies are numerous; neither the shaft encoder nor the stepper motor referred to above should be viewed as limiting. Optical, sonar, tilt sensor, and radar type devices are well known and may be sufficiently useful and cost effective to be desirable in some embodiments. Tilt sensors, for example, attached to arms of an awning, and optical or sonar-based sensors attached to a fan fold or so-called cellular blind, are embodiments that may be suited to applications that do not extend and retract fabric shade material using motorized rollers. In addition, less widely applied technologies such as surface-acoustic-wave (SAW) devices—these can transmit pulses that travel along a strip-form device and produce detectable reflections from discontinuities in propagation characteristics caused by phenomena such as bends or partial immersion—can be effective if joined to shade fabric and spooled with the shade, with the transmitter/detector embedded in the spool, coupled through the pivot shaft, or the like, or if used for other applications. All known and future physical property sensing technologies capable of application to the present invention are subject to use.
The many features and advantages of the invention are apparent from the detailed specification, and, thus, it is intended by the appended claims to cover all such features and advantages of the invention which fall within the true spirit and scope of the invention. Further, since numerous modifications and variations will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation illustrated and described, and, accordingly, all suitable modifications and equivalents may be resorted to that fall within the scope of the invention. | A control routine for groups of remotely controlled, variable-position, position-aware, transceiver-equipped actuators manages data discrepancies by issuing a first set of generic actuation commands to start and stop the actuators, then polling the actuators to report their achieved positions. The routine then applies a rule to determine a preferred position value from among the reports and issues a second set of position-specific actuation commands to all of the actuators. The routine can further poll the actuators to confirm the extent to which the commands have been realized, and can retain and apply compensation factors for performance deviations in the individual actuators. The routine can further manage multiple groups of actuators, dissimilar activators within groups, assignment of an actuator to more than one group, and application of variable control factors as inputs modifying the rule applied by the routine for determining the commands to be issued. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a division of U.S. patent application Ser. No. 14/179,773 filed Feb. 13, 2014, which claims the benefit of U.S. Provisional Patent Application No. 61/904,129 filed Nov. 14, 2013. The disclosures of the above-referenced applications are incorporated by reference as if fully set forth in detail herein.
FIELD
The present disclosure relates to a method and a machine for assembling a propshaft assembly.
BACKGROUND
This section provides background information related to the present disclosure which is not necessarily prior art.
The consumers of modern automotive vehicles are increasingly influenced in their purchasing decisions and in their opinions of the quality of a vehicle by their satisfaction with the vehicle's sound quality. In this regard, consumers increasingly expect the interior of the vehicle to be quiet and free of noise from the power train and drive line. Consequently, vehicle manufacturers and their suppliers are under constant pressure to reduce noise to meet the increasingly stringent expectations of consumers.
Drive line components and their integration into a vehicle typically play a significant role in sound quality of a vehicle as they can provide the forcing function that excites specific driveline, suspension and body resonances to produce noise. Since this noise can be tonal in nature, it is usually readily detected by the occupants of a vehicle regardless of other noise levels. Common driveline excitation sources can include driveline imbalance and/or run-out, fluctuations in engine torque, engine idle shake, and motion variation in the meshing gear teeth of the hypoid gear set (i.e., the pinion gear and the ring gear of a differential assembly).
Propshafts are typically employed to transmit rotary power in a drive line. Modern automotive propshafts are commonly formed of relatively thin-walled steel or aluminum tubing and as such, can be receptive to various driveline excitation sources. The various excitation sources can typically cause the propshaft to vibrate in a bending (lateral) mode, a torsion mode and a shell mode. Bending mode vibration is a phenomenon wherein energy is transmitted longitudinally along the shaft and causes the shaft to bend at one or more locations. Torsion mode vibration is a phenomenon wherein energy is transmitted tangentially through the shaft and causes the shaft to twist. Shell mode vibration is a phenomenon wherein a standing wave is transmitted circumferentially about the shaft and causes the cross-section of the shaft to deflect or bend along one or more axes.
Several techniques have been employed to attenuate vibrations in propshafts including the use of foam inserts. U.S. Pat. No. 6,752,722 to Armitage, et al. for example discloses the use of a pair of foam insert members that are inserted into a propshaft tube and located at the second bending mode anti-nodes. It is known in the art to employ a vacuum to install form inserts into a propshaft tube. The installation of the foam insert(s) into a propshaft tube can be time consuming and may not be capable of locating the foam insert(s) in as precise a manner as desired.
SUMMARY
This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features.
In one form, the present teachings provide a method for assembling a propshaft assembly. The method can include: providing a tubular member, the tubular member having an annular wall with an inside circumferential surface; pushing a first ram through the tubular member; loading a damper between the first ram and a second ram; twisting the damper between the first and second rams; moving the first and second rams to translate the twisted damper into the tubular member; untwisting the damper in the tubular member; and withdrawing the first and second rams from the tubular member.
In another form, the present teachings provide a propshaft assembly machine that includes a tube holder, a headstock, a tailstock and a controller. The tube holder is configured to hold the tubular member such that a longitudinal axis of the tubular member is coincident with a central axis. The headstock has a first ram that is movable along the central axis. The tailstock has a second ram that is movable along the central axis. The controller is configured to coordinate movement of the first and second rams. At least one of the first and second rams is rotatable about the central axis to cause the damper to be twisted between the first and second rams. The controller can coordinate translation of the first and second rams to cause the damper to be installed into the tubular member.
Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.
DRAWINGS
The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.
FIG. 1 is a schematic illustration of an exemplary vehicle having a propshaft assembly constructed in accordance with the teachings of the present disclosure;
FIG. 2 is a top partially cut-away view of a portion of the vehicle of FIG. 1 illustrating a rear axle and the propshaft assembly in greater detail;
FIG. 3 is a sectional view of a portion of the rear axle and the propshaft assembly;
FIG. 4 is a top, partially cut away view of the propshaft assembly;
FIG. 5 is a schematic view of an assembly machine that is configured to compress a damper and install the damper to a tubular member of the propshaft assembly in accordance with the teachings of the present disclosure; and
FIG. 6 is schematic view in flow-chart form of an exemplary method for assembling a propshaft assembly in accordance with the teachings of the present disclosure.
Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.
DETAILED DESCRIPTION
With reference to FIG. 1 of the drawings, an exemplary vehicle constructed in accordance with the teachings of the present disclosure is generally indicated by reference numeral 10 . The vehicle 10 can include an engine 14 and a drive line 16 . The drive line 16 can include a transmission 18 , a propshaft assembly 20 , a rear axle 22 and a plurality of wheels 24 . The engine 14 can produce rotary power that can be transmitted to the transmission 18 in a conventional and well known manner. The transmission 18 can be conventionally configured and can include a transmission output shaft 18 a and a gear reduction unit (not specifically shown). As is well known in the art, the gear reduction unit can change the speed and torque of the rotary power provided by the engine such that a rotary output of the transmission 18 (which can be transmitted through the transmission output shaft 18 a ) can have a relatively lower speed and higher torque than that which was input to the transmission 18 . The propshaft assembly 20 can be coupled for rotation with the transmission output member 18 a to permit drive torque to be transmitted from the transmission 18 to the rear axle 22 where can be selectively apportioned in a predetermined manner to the left and right rear wheels 24 a and 24 b , respectively.
It will be appreciated that while the vehicle in the particular example provided employs a drive line with a rear-wheel drive arrangement, the teachings of the present disclosure have broader applicability. In this regard, a shaft assembly constructed in accordance with the teachings of the present disclosure may interconnect a first drive line component with a second drive line component to transmit torque therebetween. In the context of an automotive vehicle, the drive line components could be a transmission, a transfer case, a viscous coupling, an axle assembly, or a differential, for example.
With reference to FIG. 2 , the rear axle 22 can include a differential assembly 30 , a left axle shaft assembly 32 and a right axle shaft assembly 34 . The differential assembly 30 can include a housing 40 , a differential unit 42 and an input shaft assembly 44 . The housing 40 can support the differential unit 42 for rotation about a first axis 46 and can further support the input shaft assembly 44 for rotation about a second axis 48 that is perpendicular to the first axis 46 .
With additional reference to FIG. 3 , the housing 40 can be formed in a suitable casting process and thereafter machined as required. The housing 40 can include a wall member 50 that can define a central cavity 52 that can have a left axle aperture 54 , a right axle aperture 56 , and an input shaft aperture 58 . The differential unit 42 can be disposed within the central cavity 52 of the housing 40 and can include a case 70 , a ring gear 72 , which can be fixed for rotation with the case 70 , and a gearset 74 that can be disposed within the case 70 . The gearset 74 can include first and second side gears 82 and 86 and a plurality of differential pinions 88 , which can be rotatably supported on pinion shafts 90 that can be mounted to the case 70 . The case 70 can include a pair of trunnions 92 and 96 and a gear cavity 98 . A pair of bearing assemblies 102 and 106 can support the trunnions 92 and 96 , respectively, for rotation about the first axis 46 . The left and right axle assemblies 32 and 34 can extend through the left and right axle apertures 54 and 56 , respectively, where they can be coupled for rotation about the first axis 46 with the first and second side gears 82 and 86 , respectively. The case 70 can be operable for supporting the plurality of differential pinions 88 for rotation within the gear cavity 98 about one or more axes that can be perpendicular to the first axis 46 . The first and second side gears 82 and 86 each include a plurality of teeth 108 which meshingly engage teeth 110 that are formed on the differential pinions 88 .
The input shaft assembly 44 can extend through the input shaft aperture 58 where it can be supported in the housing 40 for rotation about the second axis 48 . The input shaft assembly 44 can include an input shaft 120 , a pinion gear 122 having a plurality of pinion teeth 124 that meshingly engage the teeth 126 that are formed on the ring gear 72 , and a pair of bearing assemblies 128 and 130 that can cooperate with the housing 40 to rotatably support the input shaft 120 . The input shaft assembly 44 can be coupled for rotation with the propshaft assembly 20 and can be operable for transmitting drive torque to the differential unit 42 . More specifically, drive torque received the input shaft 120 can be transmitted by the pinion teeth 124 to the teeth 126 of the ring gear 72 such that drive torque is distributed through the differential pinions 88 to the first and second side gears 82 and 86 .
The left and right axle shaft assemblies 32 and 34 can include an axle tube 150 that can be fixed to the associated axle aperture 54 and 56 , respectively, and an axle half-shaft 152 that can be supported for rotation in the axle tube 150 about the first axis 46 . Each of the axle half-shafts 152 can include an externally splined portion 154 that can meshingly engage a mating internally splined portion (not specifically shown) that can be formed into the first and second side gears 82 and 86 , respectively.
With reference to FIG. 4 , the propshaft assembly 20 can include a tubular member 200 , a first end connection 202 a , a second end connection 202 b , and a damper 204 . The tubular member and the first and second end connections 202 a and 202 b can be conventional in their construction and need not be described in significant detail herein. Briefly, the tubular member 200 can be formed of an appropriate structural material, such as steel or aluminum, and can include an annular wall member 224 . The annular wall member 224 can have an interior circumferential surface 228 and can define a hollow cavity 230 . Depending on the particular requirements of the vehicle 10 ( FIG. 1 ), the wall member 224 may be sized in a uniform manner over its entire length, as is shown in FIG. 4 , or may be necked down or stepped in diameter in one or more areas along its length. The first and second end connections 202 a and 202 b can be configured to couple the propshaft assembly 20 to other rotary components of the vehicle 10 ( FIG. 1 ) in a desired manner to transmit rotary power therebetween. For example, the first end connection 202 a and/or the second end connection 202 b could comprise a universal joint (e.g., Cardan or constant velocity joint) or components thereof that can be fixedly coupled to the tubular member 200 . For example, the first and second end connections 202 a and 202 b could comprise weld yokes that are welded to the opposite ends of the tubular member 200 . Optionally, one or both of the first and second end connections 202 a and 202 b can be vented to permit air to flow into or out of the hollow cavity 230 . In the particular example provided, a vent 232 is installed to each of the first and second end connections 202 a and 202 b . In the particular example provided, the vents 232 comprise holes formed in the first and second end connections 202 a and 202 b , but it will be appreciated that the vent(s) 232 can be constructed in any desired manner.
The damper 204 can be effective in attenuating shell mode vibration transmitted through the tubular member 200 , but may also be effective in attenuating other vibration modes, such as torsion mode vibration and/or bending mode vibration through the tubular member 200 . Shell mode vibration, also known as breathing mode vibration, is a phenomenon wherein a standing wave is transmitted circumferentially about the tubular member 200 and causes the cross-section of the shaft to deflect (e.g., expand or contract) and/or bend along one or more axes. Torsion mode vibration is a phenomenon wherein energy is transmitted tangentially through the shaft and causes the shaft to twist. Bending mode vibration is a phenomenon wherein energy is transmitted longitudinally along the shaft and causes the shaft to bend at one or more locations.
The damper 204 can be formed of a suitable damping material, such as a length of foam or other compressible but resilient material. In the particular example provided, the damper 204 is a length of a cylindrically-shaped closed-cell foam that can be formed of a suitable material. Examples of suitable materials include polyethylene; polyurethane; sponge rubber; PVC and vinyl nitrile blends; PP and nylon foam blends; and melamine, polyimide and silicone. It will be appreciated that various other materials, such as an open-cell foam, or that one or more apertures could be formed longitudinally through the damper 204 .
The damper 204 can have an appropriate density, such as between 1.0 pounds per cubic foot to 2.5 pounds per cubic foot, preferably between 1.2 pounds per cubic foot to about 1.8 pounds per cubic foot, and more preferably between 1.20 pounds per cubic foot to 1.60 pounds per cubic foot. In the particular example provided, the damper 204 has a density of 1.45 pounds per cubic foot. The damper 204 can be sized in a manner so that it is compressed against the inside circumferential surface 228 of the tubular member 200 to a desired degree. For example, the damper 204 can have an outer circumferential diameter that is about 5% to about 20% larger than the diameter of the inside circumferential surface 228 of the tubular member 200 , and more preferably about 10% larger than the diameter of the inside circumferential surface 228 of the tubular member 200 .
The damper 204 can be tuned for a particular vehicle configuration in part by altering one or more characteristics of the damper 204 , such as its position relative to the tubular member 200 , its length, etc. In the particular example provided, damper is disposed in the middle of the tubular member 200 .
The damper 204 can be installed to the tubular member 200 by pre-compressing the damper 204 and then sliding the (compressed) damper 204 into the tubular member 200 such that it is positioned relative to the tubular member in a desired manner. Any means may be employed to compress the damper 204 prior to its insertion into the tubular member 200 . In the particular example provided, the damper 204 compressed is twisted to achieve the desired level of compression.
With reference to FIG. 5 , an exemplary assembly tool 500 for inserting the damper 204 into the tubular member 200 is illustrated. The assembly tool 500 may be procured from the Cardinal Machine Company of Clio, Mich. The assembly tool 500 can include a base 502 , a headstock 504 , a tailstock 506 , a damper holder 508 , a tube holder 510 and a control system 512 . The base 502 can be a suitably configured structure to which the headstock 504 , the tailstock 506 , the damper holder 508 and the tube holder 510 are mounted or coupled. The headstock 504 can include a first ram 520 and a first ram movement mechanism 522 that permits the first ram 520 to be moved in an axial direction along a central axis 524 that is defined by the base 502 . The first ram movement mechanism 522 can also permit the first ram 520 to be rotated about the central axis 524 . The first ram 520 can include a first end effector 526 that is configured to engage the damper 204 as will be discussed in further detail below.
The tailstock 506 can include a second ram 530 and a second ram movement mechanism 532 that can permit the second ram 530 to be moved in an axial direction along the central axis 524 and rotated about the central axis 524 . It will be appreciated that one or both of the first and second rams 520 and 530 may be configured to be driven (by the first and second ram movement mechanisms 522 and 532 , respectively) about the central axis 524 . The second ram 530 can include a second end effector 536 that is configured to engage the damper 204 as will be discussed in further detail below.
The damper holder 508 can be configured to hold the damper 204 prior to its insertion into the tubular member 200 , as well as locate or position the damper 204 relative to the tubular member 200 prior to its insertion into the tubular member 200 . The damper holder 508 could comprise any suitable structure, such as a pair of rollers that are mounted to the base 502 . In the particular example provided, the damper holder 508 comprises at least a portion of a tubular shell that is configured to cradle the damper 204 , as well as to orient the damper 204 such that its longitudinal axis is coincident with the central axis 524 . The damper holder 508 can be positioned axially between the headstock 504 and the tailstock 506 .
The tube holder 510 can be configured to hold the tubular member 200 prior to and during the assembly process so that a longitudinal axis of the tubular member 200 is coincident with the central axis 524 and the tubular member 200 is position along the central axis 524 in an accurate and repeatable manner. For example, the tube holder 510 can comprise a set of rollers or a portion of a tubular shell 540 , which can be coupled to the base 502 , a clamping member 542 , which can clamp the tubular member 200 against the rollers or tubular shell to inhibit movement of the tubular member 200 relative to the tube holder 510 , and a stop member 546 that is fixedly coupled to the base 502 . The tubular member 200 can be slid on the tube holder 510 and abutted against the stop member 546 to position the tubular member 200 in a known manner relative to the base 502 .
The control system 512 can include a controller 550 that can coordinate the operation of the first and second ram movement mechanisms 522 and 532 .
With additional reference to FIG. 6 , which schematically depicts an exemplary assembly method, the control can proceed to block 600 where the tubular member 200 to the loaded to the tube holder 510 . It will be appreciated that the loading of the tubular member 200 to the tube holder 510 can additionally comprise abutting the tubular member 200 to the stop member 546 and clamping or otherwise securing the tubular member 200 to the tube holder 510 to resist axial movement of the tubular member 200 along the central axis 524 . Control can proceed to block 604 .
In block 604 , the damper 204 can be loaded to the damper holder 508 to align the damper to the central axis 524 and optionally to locate or position the damper 204 relative to another structure, such as the base 502 or the tubular member 200 . Control can proceed to block 608 .
In block 608 , control can operate the first and second ram movement mechanisms 522 and 532 such that the first and second end effectors 526 and 536 engage the opposite ends of the damper 204 . It will be appreciated that the first ram 520 must extend through the tubular member 200 to engage the damper 204 . The first and second end effectors 526 and 536 could be configured with tines or forks to engage the ends of the damper 204 , or could be configured to clamp (and compress) the opposite ends of the damper 204 . It may be desirable to support one or both of the first and second rams 520 and 530 and/or one or both of the first and second end effectors 526 and 536 prior to engagement of the first and second end effectors 526 and 536 with the damper 204 . In the particular example provided, a support 610 is provided between the tubular member 200 and the damper 204 to support the first ram 520 when the first end effector 526 is initially positioned proximate the damper 204 . The support 610 can comprise any type of structure, such as a plate or rollers, but in the particular example provided, comprises a V-block that is mounted on a pneumatic cylinder (not specifically shown) that is mounted to the base 502 . The V-block can be normally positioned in a lowered position, which permits the end effector 526 to pass between the tube holder 510 and the damper holder 508 , but can be raised to support the distal end of the first ram 520 to ensure alignment of the longitudinal axis of the first ram 520 to the central axis 524 . In practice, it may be beneficial to have the V-block engage a positive stop that is mounted in an adjustable manner to the base 502 when the V-block is raised to ensure that the desired alignment between the longitudinal axis of the first ram 520 and the central axis 524 is achieved. Those of skill in the art will appreciate that a similar support (not shown) could be provided to directly support the second ram 530 and/or the second end effector 536 . Control can proceed to block 612 .
In block 612 , control can operate one or both of the first and second ram movement mechanisms 522 and 532 to twist the damper 204 to a point where the outside diameter of the damper 204 is smaller than the inside diameter of the annular wall member 224 ( FIG. 4 ) that forms the tubular member 200 . In the particular example provided, the damper 204 is twisted to reduce its outside diameter from about 6.38 inches (162 mm) to about 4.0 inches (102 mm). Control can proceed to block 616 .
In block 616 , control can operate the first and second ram movement mechanisms 522 and 532 to translate the (twisted) damper 204 along the central axis 524 and position the damper 204 along the length of the tubular member 200 in a desired manner. Control can proceed to block 620 .
In block 620 , control can operate one or both of the first and second ram movement mechanisms 522 and 532 to untwist the damper 204 and to thereafter release the damper 204 and withdraw the rams 520 and 530 from the tubular member 200 . Once untwisted, the damper 204 will expand and engage the inner circumferential surface 228 ( FIG. 4 ) of the annular wall member 224 ( FIG. 4 ). Control can proceed to block 624 where the tubular member 200 can be unclamped or released from the tube holder 510 and the intermediate assembly, which consists of the damper 204 installed to the tubular member 200 , can be removed from the assembly tool 500 . Control can proceed to block 628 , where the first and second end connections 202 a and 202 b ( FIG. 4 ) can be coupled to respective ends of the tubular member 200 to form the propshaft assembly 20 ( FIG. 4 ). Control can proceed to bubble 632 , where control can terminate.
The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure. | A method for assembling a propshaft assembly. The method can include: providing a tubular member, the tubular member having an annular wall with an inside circumferential surface; twisting a damper; installing the twisted damper in the tubular member; untwisting the damper in the tubular member such that the damper engages the inside circumferential surface of the annular wall. A machine for assembling a propshaft assembly is also provided. | 5 |
TECHNICAL FIELD
The present invention relates to a malfunction prevention method, a delay time shortening method, a current consumption reduction method, and a circuit area reduction method for a level shift circuit typified by a half bridge power supply.
BACKGROUND ART
In a half bridge circuit, or the like, in which switching elements are connected in series and which is driven by a high potential power supply, a level shift circuit is used in order that a high potential side switching element is driven by a low potential signal.
FIG. 1 shows a configuration diagram of a half bridge circuit 100 using a heretofore known level shift circuit. The half bridge circuit 100 shown in FIG. 1 is configured of an output circuit 110 , a high potential side drive circuit 120 , and a low potential side drive circuit 130 . The output circuit 110 is connected to the high potential side drive circuit 120 and low potential side drive circuit 130 . Also, synchronized signals are input from the exterior into each of the high potential side drive circuit 120 and low potential side drive circuit 130 .
The output circuit 110 is configured of a switching element XD 1 , a switching element XD 2 , a power source E, and a load L 1 . In the output circuit 110 , the switching element XD 1 is connected in series to the switching element XD 2 , to which the load L 1 is connected in parallel, and the high voltage power source E supplies power to the load L 1 via the switching element XD 1 . The switching element XD 1 is a high potential side switching element, and can be, for example, an n-channel or p-channel MOS transistor, a p-type or n-type IGBT (Insulated Gate Bipolar Transistor), or the like. The switching element XD 2 is a low potential side switching element, and can be, for example, an n-channel MOS transistor, an n-type IGBT, or the like. Hereafter, the switching element XD 1 and switching element XD 2 will be assumed to be n-channel MOS transistors.
The high potential side drive circuit 120 is configured of a level shift circuit, a high side driver 123 , and a power source E 1 (hereafter, the output voltage thereof will also be expressed as E 1 ). The level shift circuit is a portion of the high potential side drive circuit 120 excluding the high side driver 123 and power source E 1 , and is configured of a latch malfunction protection circuit 121 , a latch circuit 122 , a first series circuit 124 , a second series circuit 125 , feedback resistors R 3 , R 4 , R 5 , and R 6 (the resistance values thereof are also taken to be R 3 , R 4 , R 5 , and R 6 respectively), p-channel MOS transistors (hereafter expressed as PM) 1 and PM 2 , a diode D 1 and diode D 2 , and an inverter INV.
The first series circuit 124 is configured of a level shift resistor R 1 (the resistance value thereof is also taken to be R 1 ) and a high breakdown voltage n-channel MOSFET (hereafter expressed as HVN) 1 connected in series, and outputs a level shift output signal setdrn (hereafter expressed as a setdrn signal) to the latch malfunction protection circuit 121 via a first connection point Vsetb (the potential thereof is also taken to be Vsetb). Herein, the first series circuit 124 includes a first level shift output terminal (corresponding to the first connection point Vsetb) for outputting the setdrn signal to the latch malfunction protection circuit 121 , and the first level shift terminal is connected to the latch malfunction protection circuit 121 .
The second series circuit 125 is configured of a level shift resistor R 2 (the resistance value thereof is also taken to be R 2 ) and an HVN 2 connected in series, and outputs a level shift output signal resdrn (hereafter expressed as a resdrn signal) to the latch malfunction protection circuit 121 via the HVN 2 and a second connection point Vrstb (the potential thereof is also taken to be Vrstb). Herein, the second series circuit 125 includes a second level shift output terminal (corresponding to the second connection point Vrstb) for outputting the resdrn signal to the latch malfunction protection circuit 121 , and the second level shift terminal is connected to the latch malfunction protection circuit 121 .
The PM 1 is connected in parallel to the resistor R 1 configuring the first series circuit 124 . The PM 2 is connected in parallel to the resistor R 2 configuring the second series circuit 125 .
A connection point of the feedback resistors R 3 and R 5 is connected to the gate terminal of the PM 2 , and a connection point of the feedback resistors R 4 and R 6 is connected to the gate terminal of the PM 1 . A feedback circuit is configured of the inverter INV, the feedback resistors R 3 , R 4 , R 5 , and R 6 , the PM 1 , and the PM 2 . Also, regarding the resistance values of the level shift resistors R 1 and R 2 and the feedback resistors R 3 , R 4 , R 5 , and R 6 , it is taken that R 1 =R 2 , R 3 =R 4 , and R 5 =R 6 .
The setdrn signal and resdrn signal are input into the latch malfunction protection circuit 121 . The latch malfunction protection circuit 121 is a circuit that, when a false signal called dv/dt noise occurs because of source-to-drain parasitic capacitors Cds 1 and Cds 2 of the HVN 1 and HVN 2 , that is, when the potential Vsetb and the potential Vrstb are both at an L (low) level, outputs at a high impedance so that the latch circuit 122 is not affected.
The latch circuit 122 is connected to the latch malfunction protection circuit 121 and high side driver 123 . The latch circuit 122 is a circuit into which the output from the latch malfunction protection circuit 121 is input that stores and outputs the value of the input when the input is at an L or H level and, when the input is of a high impedance, holds and outputs the value stored immediately before the input reaches the high impedance.
The output terminal of the latch circuit 122 is connected via the feedback resistors R 4 and R 6 to the second connection point Vrstb, which is a connection point of the level shift resistor R 2 and HVN 2 configuring the second series circuit 125 . Also, by inverting the output of the latch circuit 122 using the inverter INV, an output the inverse of the output of the latch circuit 122 is obtained. The output terminal of the inverter INV that outputs the inverted output is connected via the feedback resistors R 3 and R 5 to the first connection point Vsetb, which is a connection point of the level shift resistor R 1 and HVN 1 configuring the first series circuit 124 .
The high side driver 123 is connected to the high potential side switching element XD 1 and latch circuit 122 , and outputs a signal HO in accordance with the output of the latch circuit 122 , thereby controlling the turning on and off of the switching element XD 1 .
The output terminal of the high side driver 123 is connected to the gate terminal of the switching element XD 1 . The latch malfunction protection circuit 121 , the latch circuit 122 , the high side driver 123 , and the low potential side power source terminal of the power source E 1 are connected to a connection point vs (hereafter, the potential thereof will also be expressed as vs) of the switching elements XD 1 and XD 2 . Also, the latch malfunction protection circuit 121 , latch circuit 122 , and high side driver 123 receive a supply of power from the power source E 1 . In the same way, although not shown, the low potential side power source terminal of the inverter INV is also connected to the connection point vs, and receives a supply of power from the power source E 1 .
One end of each of the first series circuit 124 and second series circuit 125 is connected to a power source line vb (hereafter, the potential thereof will also be expressed as vb) connected to the high potential side terminal of the power source E 1 , while the other end of each is connected to a ground potential (GND). A set signal, which is a signal input into the level shift circuit of the high potential side drive circuit 120 , is input into the gate of the HVN 1 , while a reset signal, which is a signal input into the level shift circuit of the high potential side drive circuit 120 , is input into the gate of the HVN 2 .
The anodes of the diodes D 1 and D 2 are connected to the connection point vs of the switching elements XD 1 and XD 2 , the cathode of the diode D 2 is connected to the first connection point Vsetb, and the cathode of the diode D 1 is connected to the second connection point Vrstb. The diodes D 1 and D 2 are for clamping the voltages Vsetb and Vrstb so that they do not drop to or below the potential vs, thus protecting the latch malfunction protection circuit 121 by ensuring that no overvoltage is input.
The feedback resistors R 5 and R 6 are connected to the vb potential or vs potential via a PMOS or NMOS of a CMOS circuit or logic inversion CMOS circuit (INV) used in the latch circuit 122 , but for the sake of simplicity, the PMOS and NMOS are not shown in the latch circuit 122 , and in the same way, will not be shown hereafter.
The low potential side drive circuit 130 is configured of a low side driver 131 that controls the turning on and off of the low potential side switching element XD 2 , and a power source E 2 (hereafter, the potential thereof will also be expressed as E 2 ) that supplies power to the low side driver 131 .
The low side driver 131 is supplied with power from the power source E 2 , amplifies a signal S input into the low side driver 131 , and inputs it into the gate terminal of the switching element XD 2 . According to this configuration, the switching element XD 2 is turned on (energized) when the signal S is at an H (high) level, and the switching element XD 2 is turned off (cut off) when the signal S is at an L (low) level. That is, the signal S is a signal that directly commands the turning on or off of the switching element XD 2 .
Of the set signal and reset signal input into the high potential side drive circuit 120 , the set signal is a signal that indicates the timing of the start of an on-state period (the end of an off-state period) of the switching element XD 1 , while the reset signal is a signal that indicates the timing of the start of an off-state period (the end of an on-state period) of the switching element XD 2 .
The switching elements XD 1 and XD 2 are turned on and off in a complementary way such that when one is in an on-state the other is in an off-state, except during a dead time to be described hereafter, with the potential vs of the connection point vs reaching the ground potential when the switching element XD 2 is in an on-state, and the potential vs of the connection point vs reaching the output voltage E of the power source E when the switching element XD 1 is in an on-state. Also, the load L 1 is a load that receives a supply of power from the half bridge circuit 100 , and is connected between the connection point vs and the ground potential.
In the kind of heretofore known half bridge circuit 100 shown in FIG. 1 , it is often the case that there is a large difference in potential of in the region of several hundred volts between the low potential side power source voltage E 2 and high potential side power source voltage E 1 . Because of this, it may happen that the difference in potential occurs between wiring linking the high potential side circuit and low potential side circuit and a semiconductor forming an underlay of the wiring. In particular, when the wiring potential is a high voltage due to the high potential side circuit and a subsequent stage is a low potential side circuit region, voltage generation and the effect thereof are marked. When simply applying metal wiring of a semiconductor as the wiring linking the high potential side circuit and low potential side circuit, a high electric field is generated between the wiring and the semiconductor immediately below, and various problems occur in the level shift circuit. In order to solve the heretofore described kind of problem, it is possible to apply a wire bonding method in the level shift circuit. A wire bonding method is a method whereby the drain of the HVN 1 and the first connection point Vsetb, and the drain of the HVN 2 and the second connection point Vrstb, are connected by wiring in, for example, FIG. 1 . As the wiring is point-to-point wiring distanced from the semiconductor when using a wire bonding method, it is possible to prevent a high electric field from being generated in the semiconductor region forming the underlay.
However, the application of a wire bonding method has a detrimental effect on the cost of the level shift circuit and on downsizing the product due to, for example, an increase in man-hours, the need for wiring space, and the like. Consequently, there is a demand for a level shift circuit that does not use a wire bonding method. The technologies shown in PTL 1 and PTL 2 (identified below) exist as level shift circuits that do not use a wire bonding method.
CITATION LIST
Patent Literatures
PTL 1: Japanese Patent No. 3,941,206
PTL 2: Japanese Patent No. 3,214,818
A high breakdown voltage IC having a device configuration wherein HVNs are embedded in a high breakdown voltage separation portion (hereafter referred to as an HVJT), and having parasitic resistors (R 1 in FIG. 3 of PTL 1) configured in parallel with level shift resistors configuring a level shift circuit, and a technology for controlling the resistance value of the parasitic resistors used in the level shift circuit, are described in PTL 1. FIG. 2 shows a configuration of the level shift circuit shown in PTL 1. The same reference signs are given to regions the same as in FIG. 1 , and a detailed description will be omitted. As shown in FIG. 2 , the level shift circuit shown in PTL 1 differs from the level shift circuit shown in FIG. 1 in that it includes, in addition to level shift resistors LSR 1 and LSR 2 , parasitic resistors LSRp 1 , LSRp 2 , and LSRp 3 . A first series circuit of the parallel resistance of the level shift resistor LSR 1 and parasitic resistor LSRp 1 and the HVN 1 , and a second series circuit of the parallel resistance of the level shift resistor LSR 2 and parasitic resistor LSRp 2 and the HVN 2 , are configured in the level shift circuit shown in PTL 1. The resistance values of the parasitic resistor LSRp 1 configured in parallel with the level shift resistor LSR 1 and the parasitic resistor LSRp 2 configured in parallel with the resistor LSR 2 can be controlled in the level shift circuit shown in PTL 1.
A high voltage power integrated circuit having a device configuration, differing from that in PTL 1, wherein a level shift from a low potential signal to a high potential signal is made without using wire bonding, wherein a level shift operation is possible, and that does not have a metal crossover, is described in PTL 2.
The technologies described in PTL 1 and PTL 2 are both such that the circuit area is reduced by embedding the HVNs in the HVJT region, thereby realizing a high voltage breakdown IC. Also, the kinds of method shown in PTL 1 and PTL 2 that do not use a wire bonding method differ from the wire bonding method in terms of device structure in that parasitic resistors corresponding to the level shift resistors are added, and that a parasitic resistor is added between the two series circuits.
However, the technology described in PTL 1 is such that the first series circuit and second series circuit have the same circuit configuration and device configuration. Because of this, a malfunction occurs due to the drain potentials of the turn-on signal side HVN and turn-off signal side HVN both exceeding the threshold value of a logic circuit at a subsequent stage due to the effect of the current flowing into the parasitic capacitor Cds 1 of the HVN 1 and the parasitic capacitor Cds 2 of the HVN 2 when dV/dt noise occurs. When reducing the resistance value of the level shift resistors in order to avoid this malfunction, the current flowing through the level shift resistors increases when an HVN is turned on and dV/dt noise occurs, and current consumption increases. Also, when the resistance value of the level shift resistors is not reduced, it is necessary to strengthen a noise cancellation function such as a low-pass filter in order to prevent a malfunction caused by level shift output fluctuation due to the occurrence of dv/dt noise, and there is a problem in that delay time increases because of the effect of the noise cancellation function.
Also, the technology described in PTL 2 too, in the same way as the technology described in PTL 1, is such that the first series circuit and second series circuit have the same circuit configuration and device configuration, because of which there is the problem of malfunction when dV/dt noise occurs, or the like, the problem of power consumption increasing due to reducing the resistance value of the level shift resistors in order to avoid malfunction, and the problem of delay time increasing due to strengthening the noise cancellation function when the resistance value of the level shift resistors is not reduced.
Consideration will be given to a case of replacing the level shift resistors of the heretofore known level shift circuit with the parasitic resistors described in PTL 1 or PTL 2 in order to avoid wire bonding and reduce the circuit area. FIG. 3 shows an example wherein the heretofore known level shift circuit shown in FIG. 1 is configured using the HVN-embedded type of HVJT described in PTL 1. The same reference signs are given to regions the same as in FIG. 1 , and a detailed description will be omitted. The main difference between a high potential side drive circuit 220 of a half bridge circuit 200 shown in FIG. 3 and the high potential side drive circuit 120 of the half bridge circuit 100 shown in FIG. 1 is the adoption of a configuration wherein the feedback resistors R 3 and R 4 are eliminated, the level shift resistor R 1 is replaced with a parasitic resistor Rpar 1 in the semiconductor substrate, the level shift resistor R 2 is replaced with a parasitic resistor Rpar 2 in the semiconductor substrate, and a parasitic resistor Rpar 3 is connected between a first series circuit 221 and second series circuit 222 . The first series circuit 221 is configured of the PM 1 or parasitic resistor Rpar 1 and the HVN 1 , while the second series circuit 222 is configured of the PM 2 or parasitic resistor Rpar 2 and the HVN 2 . By applying the device structure described in PTL 1, PTL 2, and the like in this way, it is possible to configure a level shift circuit without using wire bonding in the half bridge circuit 200 shown in FIG. 3 .
The resistance value of the parasitic resistors varies depending on temperature, power source voltage, and the like. FIG. 4 shows the temperature dependency of the parasitic resistor resistance value. As shown in FIG. 4 , the parasitic resistor resistance value is 3 kΩ when the temperature is −50° C., while the resistance value is 10 kΩ when the temperature is 150° C. FIG. 5 shows the power source voltage dependency of the parasitic resistor resistance value. As shown in FIG. 5 , the parasitic resistor resistance value is 3 kΩ when the voltage between the vb and GND is 0V, while the resistance value is 30 kΩ when the voltage between the vb and GND is 800V. In this way, the resistance value of the parasitic resistors, which are resistors in the semiconductor substrate, has temperature dependency and power source voltage dependency. Because of this, the rise time of the setdrn signal and resdrn signal varies in accordance with the temperature and power source voltage conditions, which may affect the operation of the level shift circuit, as will be described hereafter.
Also, the resistance value of the parasitic resistor Rpar 3 provided between the first series circuit 221 and second series circuit 222 varies depending on the distance between the HVN 1 and HVN 2 . FIG. 6 shows the dependency of the parasitic resistor Rpar 3 resistance value on the distance between the HVN 1 and HVN 2 . As shown in FIG. 6 , the parasitic resistor Rpar 3 resistance value is 500 kΩ when the distance between the HVN 1 and HVN 2 is 1,000 μm.
In the level shift circuit shown in FIG. 3 , the resistance value of the parasitic resistors Rpar 1 and Rpar 2 is regulated so as to be around 10 kΩ, while the resistance value of the parasitic resistor Rpar 3 is regulated so as to be around 500M. When the resistance value of the parasitic resistor Rpar 3 is on the high side, it is possible to reduce the effect when the level shift circuit carries out each operation.
The half bridge circuit 200 shown in FIG. 3 can change the potential at one end of the feedback resistors R 5 and R 6 to the vb potential or the vs potential in accordance with the latch circuit 122 output status by changing the connection status of the feedback resistors R 5 and R 6 in accordance with the latch circuit 122 output status. FIG. 7 shows an equivalent circuit diagram of the level shift circuit shown in FIG. 3 when an output HO of the high side driver 123 is at an L level, while FIG. 8 shows an equivalent circuit diagram of the level shift circuit shown in FIG. 3 when the output HO is at an H level. As shown in FIG. 7 , when the output HO is at an L level, the parasitic resistor Rpar 1 and feedback resistor R 5 are in a condition wherein they are connected in parallel, while the parasitic resistor Rpar 2 and feedback resistor R 6 are in a condition wherein they are connected in series. Consequently, by the gate potential of the PM 1 becoming lower than the potential vb and the PM 1 ceasing to be in a cut off state, the impedance of the output terminal of the first series circuit 221 decreases, and by the gate potential of the PM 2 becoming the potential vb and the PM 1 becoming cut off, the impedance of the output terminal of the second series circuit 222 increases. As shown in FIG. 8 , when the output HO is at an H level, the parasitic resistor Rpar 1 and feedback resistor R 5 are in a condition wherein they are connected in series, while the parasitic resistor Rpar 2 and feedback resistor R 6 are in a condition wherein they are connected in parallel. Consequently, by the gate potential of the PM 1 becoming the potential vb and the PM 1 becoming cut off, the impedance of the output terminal of the first series circuit 221 increases, and by the gate potential of the PM 2 becoming lower than the potential vb and the PM 1 ceasing to be in a cut off state, the impedance of the output terminal of the second series circuit 222 decreases.
FIG. 9 shows an operation time chart of the level shift circuit shown in FIG. 3 . On the input pulse of the set signal switching to an H level at a time t 1 , the setdrn signal drops to the vs potential, and the latch output starts to rise to an H level. While the input pulse of the set signal is at an H level, the setdrn signal continues to be at the vs potential level. On the output of the latch circuit 122 switching from an L level to an H level at a time t 2 , the parallel/series condition of the feedback resistors R 5 and R 6 switches. On the input pulse of the set signal switching from an H level to an L level at a time t 3 , the setdrn signal rises. On the input pulse of the reset signal switching to an H level at a time t 4 , the resdrn signal drops to the vs potential, and the latch output starts to fall to an L level. While the input pulse of the reset signal is at an H level, the resdrn signal continues to be at the vs potential level. On the output of the latch circuit 122 switching from an H level to an L level at a time t 5 , the parallel/series condition of the feedback resistors R 5 and R 6 switches. On the input pulse of the reset signal switching from an H level to an L level at a time t 6 , the resdrn signal rises.
When the timing of the inversion (setting) of the output of the latch circuit 122 is earlier than the input pulse width of the set signal, the impedance of the output terminal of the first series circuit 221 when the setdrn signal starts to rise becomes high, as heretofore described, the time constant of a time constant circuit configured of this and the parasitic capacitor Cds 1 increases, and the rise of the setdrn signal is delayed.
Also, when utilizing the parasitic resistors Rpar 1 and Rpar 2 as level shift resistors, the rise time fluctuates due to the effect of temperature and power source voltage, as heretofore described. As shown in FIG. 4 and FIG. 5 , the resistance value of the parasitic resistors Rpar 1 and Rpar 2 increases when the temperature or voltage rises. When the resistance value of the parasitic resistors Rpar 1 and Rpar 2 increases, the delay in the rise of the setdrn signal and resdrn signal increases, but provided that the pulses of the set signal and reset signal are generated singly, there is no problem however long the rise of the setdrn signal and resdrn signal is delayed. However, when the resistance value of the parasitic resistors Rpar 1 and Rpar 2 is high, the pulse interval between the set signal and reset signal is short, the pulses of the set signal and reset signal are generated continuously, and the next pulse falls before the previous pulse has finished rising, both the setdrn signal and resdrn signal will be at an L level. As dV/dt noise is generated when both the setdrn signal and resdrn signal are at an L level, it is arranged, in order to combat the generation of dV/dt noise, that the latch malfunction protection circuit 121 does not transmit this state to a subsequent circuit. Consequently, as the subsequent pulse does not become effective until the previous pulse has finished rising, the delay time increases, as shown in FIG. 9 , and responsiveness worsens.
FIG. 10 shows circuit simulation results for the half bridge circuit 200 shown in FIG. 3 when the pulse interval between the set signal and reset signal is 0.5 μs. FIG. 11 shows circuit simulation results for the half bridge circuit 200 shown in FIG. 3 when the pulse interval between the set signal and reset signal is 0.2 μs. As shown in FIG. 10 , when the pulse interval between the set signal and reset signal is 0.5 μs, the latch output waveform shown by the broken line when the parasitic resistor resistance value is 5 kΩ, and the latch output waveform shown by the solid line when the parasitic resistor resistance value is 35 kΩ, are the same.
However, as shown in FIG. 11 , when comparing the output waveform when the parasitic resistor resistance value is 5 kΩ and the output waveform when the parasitic resistor resistance value is 35 kΩ when the pulse interval between the set signal and reset signal is 0.2 μs, it can be seen that a delay occurs in the latch output waveform when the parasitic resistor resistance value is 35 kΩ.
SUMMARY
The invention provides a level shift circuit that does not affect delay time, regardless of the size of parasitic resistor resistance value.
In order to solve the heretofore described problem, the invention according to a first aspect is a level shift circuit, characterized by including a first series circuit wherein a first resistor in a semiconductor substrate, a first switching element connected to an input terminal that inputs a first level shift input signal, and a first level shift output terminal for outputting a first level shift output signal are connected in series, a second series circuit wherein a second resistor in a semiconductor substrate, a second switching element connected to an input terminal that inputs a second level shift input signal, and a second level shift output terminal for outputting a second level shift output signal are connected in series, a rise detector circuit, connected to the first series circuit and second series circuit and into which are input the first level shift output signal and second level shift output signal output from the first series circuit and second series circuit respectively, that compares the rise potential of the first level shift output signal and second level shift output signal with a predetermined threshold value, and outputs a first output signal and second output signal, which are pulse outputs of a constant duration, when the threshold value is exceeded, a third switching element connected in parallel to the first resistor, wherein the source terminal of the third switching element is connected to a power source potential, the drain terminal of the third switching element is connected to the first level shift output terminal, and the gate terminal of the third switching element is connected to the rise detector circuit, and a fourth switching element connected in parallel to the second resistor, wherein the source terminal of the fourth switching element is connected to a power source potential, the drain terminal of the fourth switching element is connected to the second level shift output terminal, and the gate terminal of the fourth switching element is connected to the rise detector circuit, wherein the third switching element is turned on by the first output signal from the rise detector circuit, and the fourth switching element is turned on by the second output signal from the rise detector circuit.
The level shift circuit according to a second aspect is the level shift circuit according to the first aspect, characterized in that the first resistor and second resistor are parasitic resistors in the semiconductor substrate.
The level shift circuit according to a third aspect is the level shift circuit according to the first or second aspects, characterized by including a logic circuit that outputs a third output signal when either of the first output signal or second output signal is output from the rise detector circuit, wherein a dead time is provided for the input times of the first level shift input signal and second level shift input signal, the output pulse width of the rise detector circuit is equal to or less than the dead time, and the third switching element and fourth switching element are turned on when the third output signal is output.
The level shift circuit according to a fourth aspect is the level shift circuit according to any one of the first to third aspects, characterized by further including a latch malfunction protection circuit, into which the first level shift output signal and second level shift output signal are input, that outputs a high impedance signal when both the first level shift output signal and second level shift output signal are at an L level, and a latch circuit, into which an output from the latch malfunction protection circuit is input, that stores and outputs the value of the output from the latch malfunction protection circuit when the output is at an L or H level and, when the output from the latch malfunction protection circuit is of a high impedance, holds the value stored immediately before the input reaches the high impedance, and outputs the stored value together with an inverse signal of the stored value, wherein one output terminal of the latch circuit is connected via a first feedback resistor to the first level shift output terminal, and the other output terminal is connected via a second feedback resistor to the second level shift output terminal.
The level shift circuit according to a fifth aspect is the level shift circuit according to any one of the first to fourth aspects, characterized by further including a first feedback transistor connected in parallel to the first resistor and a second feedback transistor connected in parallel to the second resistor, wherein the gate of the first feedback transistor is connected to the second level shift output terminal, and the gate of the second feedback transistor is connected to the first level shift output terminal.
Advantageous Effects of Invention
According to the invention according to the first aspect, it is possible to reduce delay time to a minimum, even when using resistors with temperature characteristics and power source voltage characteristics as level shift resistors. Also, it is possible to shorten the pulse input interval between a set side pulse input and a reset side pulse input.
According to the invention according to the second aspect, it is possible to use parasitic resistors with temperature characteristics and power source voltage characteristics as level shift resistors.
According to the invention according to the third aspect, it is possible to prevent shoot-through current when the level shift circuit according to the first aspect is operating.
According to the invention according to the fourth and fifth aspects, it is possible to prevent malfunction caused by dV/dt noise.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a configuration diagram of a half bridge circuit using a heretofore known level shift circuit.
FIG. 2 shows a configuration diagram of the heretofore known level shift circuit.
FIG. 3 shows a circuit configuration diagram when level shift resistors in the heretofore known level shift circuit configuration are replaced with parasitic resistors.
FIG. 4 is a diagram showing the temperature dependency of parasitic resistor resistance value.
FIG. 5 is a diagram showing the voltage dependency of parasitic resistor resistance value.
FIG. 6 is a diagram showing the dependency of parasitic resistor resistance value on the distance between HVNs.
FIG. 7 shows an equivalent circuit diagram of the circuit configuration shown in FIG. 3 when a feedback resistor R 5 and parasitic resistor Rpar 1 are in a condition in which they are connected in parallel, while a feedback resistor R 6 and parasitic resistor Rpar 2 are in a condition in which they are connected in series.
FIG. 8 shows an equivalent circuit diagram of the circuit configuration shown in FIG. 3 when the feedback resistor R 5 and parasitic resistor Rpar 1 are in a condition in which they are connected in series, while the feedback resistor R 6 and parasitic resistor Rpar 2 are in a condition in which they are connected in parallel.
FIG. 9 shows an operation time chart of the level shift circuit shown in FIG. 3 .
FIG. 10 is a diagram showing circuit simulation results for the half bridge circuit 200 shown in FIG. 3 when the pulse interval between the set signal and reset signal is 0.5 μs.
FIG. 11 is a diagram showing circuit simulation results for the half bridge circuit 200 shown in FIG. 3 when the pulse interval between the set signal and reset signal is 0.2 μs.
FIG. 12 shows a circuit configuration diagram according to Example 1 of the invention.
FIG. 13 shows an internal configuration diagram of a rise detector circuit.
FIG. 14 shows an operation time chart of the rise detector circuit shown in FIG. 13 .
FIG. 15 is a diagram showing another circuit configuration of a rise detector circuit.
FIG. 16 shows an operation time chart of the rise detector circuit shown in FIG. 15 .
FIG. 17 is a diagram showing the results of a circuit simulation when the pulse interval between a set signal and reset signal is 0.5 μs.
FIG. 18 is a diagram showing the results of a circuit simulation when the pulse interval between a set signal and reset signal is 0.2 μs.
FIG. 19 is a diagram showing a circuit configuration of a half bridge circuit 400 according to Example 2 of the invention.
FIG. 20 is a diagram showing a circuit configuration of a rise detector circuit for utilizing the circuit configuration according to Example 2.
FIG. 21 is a diagram showing the relationship between the pulse intervals of a set signal, reset signal, and gen signal and the output waveforms of a setdrn signal and resdrn signal.
FIG. 22 is a diagram showing circuit simulation results when the pulse interval between the set signal and reset signal is 0.5 μs.
FIG. 23 is a diagram showing circuit simulation results when the pulse interval between the set signal and reset signal is 0.2 μs.
FIG. 24 is a diagram showing a circuit configuration of a half bridge circuit 500 according to Example 3 of the invention.
FIG. 25 is a diagram showing circuit simulation results when the pulse interval between the set signal and reset signal is 0.5 μs.
FIG. 26 is a diagram showing circuit simulation results when the pulse interval between the set signal and reset signal is 0.2 μs.
DETAILED DESCRIPTION
Example 1
FIG. 12 is a circuit configuration diagram according to Example 1 of the invention. The same reference signs are given to regions the same as in FIG. 3 , and a detailed description will be omitted. As shown in FIG. 12 , a half bridge circuit 300 according to Example 1 of the invention differs from a half bridge circuit 200 shown in FIG. 3 in that the half-bridge circuit 300 further includes a PM 11 , a PM 21 , a first rise detector circuit 321 , and a second rise detector circuit 322 . The resistance values of parasitic resistors Rpar 1 and Rpar 2 in a high potential side drive circuit 320 of the half-bridge circuit 300 shown in FIG. 12 can be controlled as described in PTL 1. As one example, the parasitic resistors Rpar 1 and Rpar 2 at a predetermined power source voltage and predetermined temperature conditions are taken to be of 10 kΩ, taking into consideration the temperature characteristics shown in FIG. 4 and power source voltage characteristics shown in FIG. 5 . The resistance value of a parasitic resistor Rpar 3 at a predetermined power source voltage and predetermined temperature, based on the dependency on the distance between HVN 1 and HVN 2 shown in FIG. 6 , is taken to be the 500 kΩ when the distance between HVN 1 and HVN 2 is 1,000 μm.
The first rise detector circuit 321 is connected to a first series circuit 221 and the gate terminal of the PM 11 , detects a rise of a setdrn signal output from the first series circuit 221 , and inputs a set-gen signal into the gate terminal of the PM 11 . The second rise detector circuit 322 is connected to a second series circuit 222 and the gate terminal of the PM 21 , detects a rise of a resdrn signal output from the second series circuit 222 , and inputs a reset-gen signal into the gate terminal of the PM 21 .
The PM 11 is connected in parallel with the parasitic resistor Rpar 1 of the first series circuit 221 , while the PM 21 is connected in parallel with the parasitic resistor Rpar 2 of the second series circuit 222 . The gate terminal of the PM 11 is connected to the output terminal of the first rise detector circuit 321 , while the gate terminal of the PM 21 is connected to the output terminal of the second rise detector circuit 322 .
FIG. 13 is an internal configuration diagram of the first rise detector circuit 321 and second rise detector circuit 322 . As shown in FIG. 13 , the first rise detector circuit 321 and second rise detector circuit 322 are configured of a delay circuit 330 , a comparator 325 , a PMOS gate signal connection terminal logic circuit 335 , and a threshold value voltage source E 3 . The first rise detector circuit 321 differs from the second rise detector circuit 322 , which inputs the resdrn signal and outputs the reset-gen signal, only in that it inputs the setdrn signal and outputs the set-gen signal. Hereafter, in order to describe the configuration of a rise detector circuit, a description will be given using the first rise detector circuit 321 as an example, but the same operation is carried out in the second rise detector circuit 322 too, except that the input signals and output signals differ, as heretofore described.
When the setdrn signal is input into the first rise detector circuit 321 , the setdrn signal is input into the comparator 325 and delay circuit 330 . The comparator 325 is such that the setdrn signal is input into one input terminal thereof while a threshold value voltage E 3 from the threshold value voltage source E 3 (the output voltage thereof is also taken to be E 3 ) is input into the other input terminal, and the comparator 325 compares the setdrn signal and threshold value voltage E 3 . The comparator 325 inputs a comparison signal CMO into the PMOS gate signal connection terminal logic circuit 335 , with the comparison signal CMO being at an H level when the signal level of the setdrn signal is higher than the threshold value voltage, and with the comparison signal CMO being at an L level when the signal level of the setdrn signal is lower than the threshold value voltage.
The delay circuit 330 delays the input setdrn signal, and inputs it into the PMOS gate signal connection terminal logic circuit 335 as a delay signal DLY. The delay circuit 330 is realized by, for example, a delay circuit using a method whereby the number of stages of a CMOS logic inverter is changed, a delay circuit wherein a resistive element and capacitive element are combined, a delay circuit using a method whereby the parameters of a resistive element and capacitive element are changed, or the like. The rise detector circuit may be configured so that, by the comparison signal CMO from the comparator 325 being input into the delay circuit 330 , the signal CMO rather than the setdrn signal is delayed.
The input terminal of the PMOS gate signal connection terminal logic circuit 335 into which the delay signal DLY is input is set to have a function of inverting and inputting the delay signal DLY, while the output terminal that outputs the set-gen signal has a function of inverting the logical product of the comparison signal CMO and the inverted delay signal DLY, and outputting the set-gen signal. That is, the comparison signal CMO and delay signal DLY are input into the PMOS gate signal connection terminal logic circuit 335 , the PMOS gate signal connection terminal logic circuit 335 sets the set-gen signal at an L level only when the comparison signal CMO is at an H level and the delay signal DLY is at an L level, sets the set-gen signal at an H level at all other times, and inputs the set-gen signal into the gate terminal of the PM 11 . In the same way, the second rise detector circuit 322 too, going through the same operation as in the case of the first rise detector circuit 321 , but with the resdrn signal as an input, inputs the reset-gen signal into the gate terminal of the PM 21 .
FIG. 14 shows an operation time chart of the rise detector circuit shown in FIG. 13 . As shown in FIG. 14 , on the setdrn signal or resdrn signal being switched from an H level to an L level at a time t 7 , the comparison signal CMO is also switched from an H level to an L level. The delay signal DLY is switched from an H level to an L level at a time t 8 . On the setdrn signal or resdrn signal starting to rise to an H level, the signal level becoming higher than the threshold value voltage E 3 at a time t 9 , and the comparison signal CMO being switched to an H level, the set-gen signal or reset-gen signal is switched from an H level to an L level. Then, as a PM 1 or PM 2 is turned on (energized), the set-gen signal or reset-gen signal rises swiftly, and the rise time is shortened. On the delay signal DLY switching to an H level at a time t 10 , the set-gen signal or reset-gen signal is also switched to an H level.
FIG. 15 shows another circuit configuration of a rise detector circuit. Hereafter, a description will be given using the first rise detector circuit 321 as an example. The first rise detector circuit 321 according to the other circuit configuration includes the delay circuit 330 and PMOS gate signal connection terminal logic circuit 335 . When the setdrn signal is input into the first rise detector circuit 321 , the setdrn signal is input into the delay circuit 330 and one input terminal of the PMOS gate signal connection terminal logic circuit 335 . The delay circuit 330 delays the input setdrn signal, and inputs it into the other input terminal of the PMOS gate signal connection terminal logic circuit 335 as the delay signal DLY. As the threshold value of the input terminals of the PMOS gate signal connection terminal logic circuit 335 is a potential intermediate between vb and vs, the PMOS gate signal connection terminal logic circuit 335 outputs the set-gen signal at an L level only when the signal level of the setdrn signal is higher than the threshold value and the delay signal DLY is at an L level, and outputs the set-gen signal at an H level at all other times. However, as the threshold value of the input terminals of the PMOS gate signal connection terminal logic circuit 335 is a potential intermediate between vb and vs, there is a drawback in that the time at which the output pulse of the first rise detector circuit 321 changes is delayed, but this drawback is eliminated by lowering the threshold value of the H level side input terminal of the PMOS gate signal connection terminal logic circuit 335 .
FIG. 16 shows an operation time chart of the rise detector circuit shown in FIG. 15 . As shown in FIG. 16 , the setdrn signal or resdrn signal is switched from an H level to an L level at the time t 7 . The delay signal DLY is switched from an H level to an L level at the time t 8 . On the setdrn signal or resdrn signal starting to rise to an H level, and the signal level becoming higher than the threshold value of the input terminals of the PMOS gate signal connection terminal logic circuit 335 at the time t 9 , the set-gen signal or reset-gen signal is switched from an H level to an L level. Then, as the PM 1 or PM 2 is turned on, the set-gen signal or reset-gen signal rises swiftly, and the rise time is shortened. On the delay signal DLY switching to an H level at the time t 10 , the set-gen signal or reset-gen signal is also switched to an H level.
FIG. 17 and FIG. 18 show results of the level shift circuit according to Example 1 shown in FIG. 12 being tested by circuit simulation. FIG. 17 shows the results of a circuit simulation when the pulse interval between a set signal and reset signal is 0.5 μs. As shown in FIG. 17 , even when comparing cases in which the resistance values of the parasitic resistors Rpar 1 and Rpar 2 are 5 kΩ and 35 kΩ, no delay occurs in latch output, which is the same as the simulation results of a heretofore known level shift circuit shown in FIG. 10 . FIG. 18 shows the results of a circuit simulation when the pulse interval between the set signal and reset signal is 0.2 μs. Despite the fact the a delay occurs in the latch output in the simulation results of a heretofore known level shift circuit shown in FIG. 11 , no delay occurs in the latch output waveform shown in FIG. 18 .
Example 2
FIG. 19 is a circuit configuration of a half bridge circuit 400 according to Example 2 of the invention. The basic circuit configuration of the half bridge circuit 400 is the same as that in Example 1. Example 2 differs from Example 1 in that the configuration is such that the first rise detector circuit 321 and second rise detector circuit 322 shown in Example 1 are eliminated, one rise detector circuit 421 is provided instead, the setdrn signal and resdrn signal output from the first series circuit 221 and second series circuit 222 are input into the rise detector circuit 421 , and one gen signal output from the rise detector circuit 421 is input into the PM 11 and PM 21 .
FIG. 20 shows a circuit configuration of the rise detector circuit 421 for utilizing the circuit configuration according to Example 2. As shown in FIG. 20 , the rise detector circuit 421 of a high potential side drive circuit 420 includes the threshold value voltage source E 3 , a first comparator 435 , a first delay circuit 436 , a first logical circuit 437 , a second comparator 438 , a second delay circuit 439 , a second logical circuit 440 , and a PMOS gate signal connection terminal logic circuit 441 .
The first comparator 435 and first delay circuit 436 are connected to the first series circuit 221 , and the setdrn signal is input into each of them. The setdrn signal is input into one input terminal of the first comparator 435 , the threshold value voltage E 3 is input into the other input terminal, and the first comparator 435 compares the setdrn signal and threshold value voltage E 3 . The first comparator 435 inputs a comparison signal CMO into the first logic circuit 437 , with the comparison signal CMO being at an H level when the signal level of the setdrn signal is higher than the threshold value voltage E 3 , and with the comparison signal CMO being at an L level when the signal level of the setdrn signal is lower than the threshold value voltage E 3 .
The first delay circuit 436 delays the input setdrn signal, and outputs it to the first logic circuit 437 as a delay signal DLY.
The comparison signal CMO and delay signal DLY are input into the first logic circuit 437 . The input terminal into which the delay signal DLY is input is set to have a function of inverting and inputting the delay signal DLY from the first delay circuit 436 , while the output terminal of the first logic circuit 437 has a function of inverting the logical product of the comparison signal CMO from the first comparator 435 and the inverted delay signal DLY, and outputting a signal.
The second comparator 438 and second delay circuit 439 are connected to the second series circuit 222 , and the resdrn signal is input into each of them. The resdrn signal is input into one input terminal of the second comparator 438 , the threshold value voltage E 3 is input into the other input terminal, and the second comparator 438 compares the resdrn signal and threshold value voltage E 3 . The second comparator 438 inputs a comparison signal CMO into the second logic circuit 440 , with the comparison signal CMO being at an H level when the signal level of the resdrn signal is higher than the threshold value voltage E 3 , and with the comparison signal CMO being at an L level when the signal level of the resdrn signal is lower than the threshold value voltage E 3 .
The second delay circuit 439 delays the input resdrn signal, and outputs it to the second logic circuit 440 as a delay signal DLY.
The comparison signal CMO and delay signal DLY are input into the second logic circuit 440 . The input terminal into which the delay signal DLY is input is set to have a function of inverting and inputting the delay signal DLY from the second delay circuit 439 , while the output terminal of the second logic circuit 440 has a function of inverting the logical product of the comparison signal CMO from the second comparator 438 and the inverted delay signal DLY, and outputting a signal.
The PMOS gate signal connection terminal logic circuit 441 inputs a gen signal into the PM 11 and PM 21 , with the gen signal being at an L level in a case in which an output when the comparison signal CMO of the first comparator 435 is at an H level and the delay signal DLY of the second delay circuit 436 is at an L level is input from the first logic circuit 437 , and in a case in which an output when the comparison signal CMO of the second comparator 438 is at an H level and the delay signal DLY of the second delay circuit 439 is at an L level is input from the second logic circuit 440 , and with the gen signal being at an H level in all other cases.
When applying the rise detector circuit shown in FIG. 20 , a temporal restriction (a dead time DT) is provided for the set signal and reset signal.
FIG. 21 shows the relationship between the pulse intervals of the set signal, reset signal, and gen signal and the output waveforms of the setdrn signal and resdrn signal. As shown in FIG. 21 , on the set signal being switched from an L level to an H level at a time t a , the setdrn signal is switched to an L level. On the set signal being switched from an H level to an L level at a time t b , the setdrn signal starts to rise to an H level, and on the signal level of the setdrn signal becoming higher than the threshold value voltage E 3 at a time t c , the gen signal is switched from an H level to an L level. On the delay signal DLY of the first delay circuit switching to an H level at a time t d , the set-gen signal or reset-gen signal is also switched to an H level. On the reset signal being switched from an L level to an H level at a time t e , the resdrn signal is switched to an L level. On the reset signal being switched from an H level to an L level at a time t f , the resdrn signal starts to rise to an H level, and on the signal level of the resdrn signal becoming higher than the threshold value voltage E 3 at a time t g , the gen signal is switched from an H level to an L level. On the delay signal DLY of the first delay circuit switching to an H level at a time t h , the gen signal is also switched to an H level.
A dead time period DT is provided for the set signal and reset signal so that the pulses of the two are not superimposed. That is, unless the dead time period DT has elapsed since the fall of one of the set signal or reset signal, the other signal is not raised. Further, a pulse width PW of the gen signal of the rise detector circuit 421 is regulated so as to be equal to or less than DT. The pulse width PW of the gen signal can be regulated by the delay circuit shown in FIG. 20 . It is assumed that the output amplitude of the gen signal is of a voltage level such that a turning on and off of the PM 11 and PM 21 is possible.
FIG. 22 and FIG. 23 show circuit simulation results for the level shift circuit of FIG. 19 . FIG. 22 is the test results when the pulse interval between the set signal and reset signal is 0.5 μs, while FIG. 23 is the test results when the pulse interval between the set signal and reset signal is 0.2 μs. As shown in FIG. 22 and FIG. 23 , no delay in latch output due to a difference in parasitic resistance occurs, even when the pulse intervals differ.
There is an advantage in applying the rise detector circuit 421 shown in FIG. 20 in that, even when a rise of the setdrn signal or resdrn signal is detected, the PM 11 and PM 21 are turned on, the set-gen signal or reset-gen signal rises swiftly, and the rise time is shortened. Owing to a relative operation of the parasitic resistors Rpar 1 and Rpar 2 and feedback resistors R 5 and R 6 , there is no change in an operation whereby one series circuit is connected in parallel while the other series circuit is connected in series, because of which a relationship between the impedances of the first series circuit 221 and second series circuit 222 wherein one is low while the other is high is maintained, and a relationship such that no malfunction occurs is maintained.
Example 3
FIG. 24 shows a circuit configuration of a half bridge circuit 500 according to Example 3 of the invention. The same reference signs are given to regions the same as in FIG. 19 , and a detailed description will be omitted. A high potential side drive circuit 520 of the half bridge circuit 500 shown in FIG. 24 is such that a first series circuit 521 is configured using a series circuit of the parasitic resistor Rpar 1 and a parasitic resistor Rpar 4 , while a second series circuit 522 is configured using a series circuit of the parasitic resistor Rpar 2 and a parasitic resistor Rpar 5 . The PM 11 and PM 21 are connected in parallel to the parasitic resistor Rpar 1 and parasitic resistor Rpar 2 respectively. The source terminal of the PM 1 is connected to a power source line Vb, while the drain terminal is connected to a first connection point Vsetb, and the gate terminal is connected via a second connection point Vrstb and the feedback resistor R 6 to the output terminal of a latch circuit 122 . The source terminal of the PM 2 is connected to the power source line Vb, while the drain terminal is connected to the second connection point Vrstb, and the gate terminal is connected via the first connection point Vsetb and the feedback resistor R 5 to the output terminal of an inverter INV.
FIG. 25 and FIG. 26 show circuit simulation results for the level shift circuit shown in FIG. 24 . FIG. 25 is the test results when the pulse interval between the set signal and reset signal is 0.5 μs, while FIG. 26 is the test results when the pulse interval between the set signal and reset signal is 0.2 μs. As shown in FIG. 25 and FIG. 26 , no delay in latch output due to a difference in parasitic resistance occurs, even when the pulse intervals differ.
INDUSTRIAL APPLICABILITY
In the description thus far, the Rpar 1 , Rpar 2 , Rpar 4 , and Rpar 5 have been adopted as parasitic resistors in a semiconductor substrate but, the invention not being limited to parasitic resistance, the normal resistance in a semiconductor substrate may be applied instead of the parasitic resistors Rpar 1 , Rpar 2 and Rpar 4 . Even when these resistors have properties in accordance with FIGS. 4 to 6 , the effect thereof can be suppressed by the invention. | A level shift circuit does not affect delay time, regardless of the size of resistor resistance value. The level shift circuit includes first and second series circuits wherein first and second resistors and first and second switching elements are connected in series, rise detector circuits that compare the rise potentials of output signals of the first and second series circuits with a predetermined threshold value, and output first and second output signals, which are pulse outputs of a constant duration, when the threshold value is exceeded, and third and fourth switching elements connected in parallel to the first and second resistors respectively. The gate terminals of the third and fourth switching elements are connected to the rise detector circuits, and the third and fourth switching elements are turned on by the first and second output signals respectively. | 7 |
CROSS REFERENCE TO RELATED APPLICATION
This is a division of U.S. patent application Ser. No. 627,028, filed July 2, 1984 and now U.S. Pat. No. 4,569,109.
TECHNICAL FIELD
This invention relates to split bearing assemblies of the type comprising a main body and a separable cap which are secured together to define a journal encircling bearing, or bearing receiving opening, for supporting a journal of a rotatable shaft, or the like. Further the invention relates to methods and means for making split bearing assemblies of the type described.
BACKGROUND
It is known in the mechanical arts to provide split bearing assemblies in various structural and machine components for supporting, or being supported by, the journals of rotating shafts and the like. Examples of applications for split bearing assemblies include engine crankshaft main and connecting rod bearing assemblies, some camshaft bearing assemblies, crank-supporting bearing assemblies for compressors, presses and other machines, and other rotatable shaft-supporting bearing assemblies, in all of which a removable saddle-like bearing cap is secured to a mating saddle-like main body to provide for the installation and removal of a rotatable shaft, an attached connecting rod, or another device.
Undoubtedly the most common method for manufacturing the separable main bodies and caps of split bearing assemblies is to separately form them by casting, forging or otherwise, whether they be for connecting rods, engine crankcases or other devices, and to subsequently bolt, or otherwise secure together, the caps and the main bodies. In many cases, finish machining of the journal encircling opening is completed after initial assembly of these components. This manufacturing method requires a large number of machining operations, as well as preliminary assembly and disassembly of the components, before the supporting or supported shaft may be installed.
Another known manufacturing method involves forming the main body and cap integral and separating them during manufacture by sawing or cutting away excess material provided to initially join the components. This method also requires machining of the connecting surfaces and other portions, generally including preliminary assembly.
In the case particularly of connecting rods, the prior art teaches other methods of forming the main body and cap as integral members and completely machining all necessary surfaces, including the journal encircling opening or bore, before separating the main body and cap members. The members are separated by material fracture techniques which involve fracturing the components along predetermined fracture planes, leaving interlocking rough surfaces that are capable of being re-engaged for assembly of the components into an operating assembly.
The prior art fracture techniques include various methods of weakening the separation planes, such as by drilling holes therein and/or providing weakening notches along one or more edges. Embrittlement of the material in the separating planes may also be provided for either by material selection, heat treatment (including hardening of various types), or by freezing the material to reduce its temperature below the embrittlement point.
The various types of prior fracture techniques introduce various problems, among which are reduction of the engageable surface area of the separated parts that reduces the allowable clamping load and, in some cases, the introduction of excessive bending of the separating parts which results in yielding deformation of metal along the edges that interfere with proper reassembly of the separated components. Deformation of the previously machined opening can also be a problem with some methods. Such difficulties limit the useable applications of fracture techniques and sometimes require additional machining operations to clean up or correct deformation and yielding problems.
SUMMARY OF THE INVENTION
The present invention provides methods and apparatus for making split bearing assemblies which substantially reduce the amount of machining over the most common methods. The methods and apparatus of the present invention utilize novel fracture techniques that eliminate problems of bending deformation during fracture and avoid the necessity for additional machining after separation. The novel methods are applicable not only to connecting rods and similar items to which fracture separation has been previously applied, but also to components having a plurality of bearing caps connected to a single body, such as an engine block, to provide a novel assembly. Novel splitting apparatus are provided for the manufacture of engine blocks and the like.
The various features and advantages of the method and apparatus as well as the novel structures involved will be more completely disclosed and understood in the following decsription of certain specific embodiments, chosen for purposes of illustration, together with the accompanying drawings.
BRIEF DRAWING DESCRIPTION
In the drawings:
FIG. 1 is a plan view of the crankpin-encircling end of a connecting rod, forming a split bearing assembly in accordance with the invention;
FIG. 2 is a longitudinal cross-sectional view from the plane indicated by the line 2--2 of FIG. 1 showing the interior of the bearing bore;
FIG. 3 is a fragmentary transverse cross-sectional view from the plane indicated by the line 3--3 of FIG. 2 showing the cap securing means;
FIGS. 4 and 5 are fragmentary plan views showing the results of sequential fracture separation steps of the manufacturing process;
FIG. 6 is a pictorial view illustrating known apparatus for performing a fracture separation process;
FIG. 7 is a fragmentary end view of the crankshaft carrying portion of the engine block, including attached main bearing caps;
FIG. 8 is a partial cross-sectional view from the plane indicated by the line 8--8 of FIG. 7 and showing the bearing bores;
FIG. 9 is a fragmentary cross-sectional view from the plane indicated by the line 9--9 of FIG. 8 showing the securing means;
FIGS. 10 and 11 are fragmentary pictorial views of one of the crankcase webs before and after the fracture separation steps of the manufacturing method;
FIGS. 12 and 12A are fragmentary cross-sectional views through alternative embodiments of split bearing assemblies for supporting crankshaft main journals;
FIG. 13 is a side view of a novel gang splitting tool adapted for use in simultaneous fracture separation of multiple main bearing caps from their associated bodies, and
FIG. 14 is cross-sectional view from the plane indicated by the line 14--14 of FIG. 13 showing the splitting die construction.
DETAILED DESCRIPTION
FIGS. 1-3 of the drawings illustrate the crankpin-encircling large end of a connecting rod assembly generally indicated by numeral 20 and of the type for use in internal combustion engines and the like. Connecting rod 20 includes a saddle-like main body 21 which is bifurcated to form first and second legs 22, 24 respectively and a removable saddle-like bearing cap 25 that is also bifurcated to define first and second legs 26, 28, respectively. The first legs 22, 26 of the body and cap have mating ends 29, 30 respectively and the second legs 24, 28 of the body and cap have mating ends 32, 33, respectively.
The mating ends 29, 30 and 32, 33 are secured in end-to-end engagement so that the saddle-like members 21, 25 define a journal receiving opening 34 in which a crankpin journal, not shown, may be received. Commonly, split insert bearing shells, not shown, are clamped within the journal receiving opening 34 to provide a suitable bearing surface for relative rotation of the crankpin, not shown, within the connecting rod.
As shown, the bifurcated legs 22, 24, 26, 28 of the body and cap incorporate integral bolt bosses through which bolt openings 36 extend from the distal ends of the cap legs 26, 28 through the mating ends 29, 30, 32, 33 and into the legs 22, 24 of the body to receive body bolts 37 that threadably engage the legs 22, 24 of the body and secure the legs 26, 28 of the cap in engagement therewith.
The mating ends 29, 30 and 32, 33 of the legs of the cap and body are comprised of rough, uneven mating surfaces formed by the fracture separation methods to be subsequently described and lying generally along split planes 38, 39 located on opposite sides of the opening 34. In the present instance the split planes lie on a common transverse diametral plane passing through the axis 40 of the pin encircling opening 34 and at right angles to the main longitudinal axis 41 of the connecting rod. It would be possible, however, to form the split planes 38, 39 outside of, or at angles to, the diametral plane. At the inner edges of the mating ends, along the split planes 38, 39, notches 42, 44 are formed in the periphery of and extending longitudinally for the length of the cylindrical opening 34 to initiate and locate the starting points of separation in the subsequent fracture steps and form the inner edges of the mating legs of the cap and body. The cap may be formed of any suitable material such as cast iron, steel or aluminum as will be subsequently more fully discussed.
The steps in a preferred form of method, according to the invention, for manufacturing the connecting rod assembly of FIGS. 1-3 are as follows. An integral unfinished connecting rod 20, including unseparated body and cap portions, 21, 25, respectively, with a pin-encircling opening defined thereby, is first formed in any suitable manner, such as, by casting, forging or the like. The integral rod is then machined to its finished dimensions by machining the bore 34, drilling and threading the bolt openings 36 and finishing the opposite sides of the connecting rod at the ends of the bore 34, if desired. Preferably, notches 42, 44 are also machined (or otherwise formed such as by casting or forging ) extending longitudinally along the opposite lateral sides of the bore 34.
Following finish machining, preparation is made for separating the bearing cap 25 from the main body 21. For this purpose, the material, at least that in the split planes 38 and 39, must be sufficiently brittle. If the material of the connecting rod is inherently brittle, such as cast iron and some aluminum alloys, no additional preparation may be required. Less brittle materials, such as steel, may require heat treatment or selective hardening by any suitable process to embrittle the material sufficiently along the split planes to avoid excessive yielding when fractured. As a third alternative, ductile or insufficiently brittle materials may be made temporarily brittle for processing purposes by reducing the temperature to a sufficiently low level. This may be done, for example, by soaking the parts in liquid nitrogen until they reach a temperature level of -150° F. in preparation for the fracturing step.
When the material along the split planes is, or has been made, sufficiently brittle, force applying means are utilized to apply a separating force on opposite sides of the bore 34, acting outwardly in opposite directions parallel to the longitudinal axis 41 of the connecting rod, as shown by the arrows in FIG. 4 of the drawings. The application of force in this manner causes tension across the split planes extending outwardly from the notches on opposite sides of the opening 34. The tension causes a crack 45 to progress from the edge of either one of the notches 44 generally along the normal split plane 39 to the outer edge of the connecting rod, causing fracture separation of one pair of the mating legs, in this case 24 and 28, and forming their mating ends as previously described. (If desired the tension can be restricted to a selected one of the split planes. Also other means for limiting initial cracking to one pair of legs can be applied as will be discussed subsequently.)
After cracking of one pair of legs, continued force application along the connecting rod longitudinal axis, causing further expansion of the opening 34, would cause the formation of a second crack along the split plane 38, on the opposite side of the connecting rod and result in fully separating the cap and main body. However, experience has shown that completing the fracture in this manner may cause excessive bending of the material at the outer edges of the mating legs defined by the second crack. This bending results in deformation of the material along the outer edge which can interfere with proper mating engagement of the cap and main body upon attempted reassembly of the two members. Thus, it is advisable to provide means to prevent excessive opening of a space at the point of crack 45 which would allow the devlopment of bending stresses to the material in the opposite split plane.
This may be accomplished, as shown in FIG. 5, by applying a clamping force on opposite ends of the initially separated legs after the crack 45 has been formed. Continued application, or reapplication, of the longitudinal separating force against the cap and main body sides of the bore 34 is, then, effective to create a second crack 46, starting from the notch 42 and extending outwardly, generally in the split plane 38 to the outer edge of the rod, causing fracture separation of the mating legs 22, 26 and forming their mating ends.
Since the clamping force maintained against the already separated mating legs 24, 28 on the other side of the rod prevents their moving apart in a substantial degree, bending of the material at the ends of the legs 22, 26, defined by the opposite crack 46, is prevented and the problem of yielding deformation is avoided. Thus, upon assembly of the cap 25 to the main body 21, the installation of closely fitted body bolts 37 will be effective to positively realign the members in their original positions and allow the rough hills and interstices of the opposing fractured surfaces to tightly engage and form a securely clamped assembly.
If desired, it is contemplated that the fracture process may be accomplished with retaining bolts already loosely installed in the openings 36 to prevent full disassembly of the cap and main body. Thus, the parts are retained in assembly until such time as installation of the finished part in an actual engine or other mechanism is desired. In this manner, the uniquely matched cap and rod will be maintained together in proper orientation at all times until final assembly, reducing the possibility of assembly errors.
FIG. 6 illustrates known simple force applying means, in the form of a separating tool adapted to apply the desired separating force to the opposite sides of bore 34 of the cap and main body without substantial deformation of either member. Tool 48 consists of a pair of semi-cylindrical flat-sided pressure dies 49, 50 respectively containing longitudinal grooves 52, 53 extending along their flat sides 54, 55. When the dies are placed with their flat sides together, the grooves 52, 53 cooperate to form a rectangular opening for a separating wedge 56, the grooves having oppositely angled bottoms arranged to engage the angled sides 57, 58 of the wedge.
In use, the die elements 49, 50 are inserted into the opening 34 with their flat sides 54, 55 together and generally aligned with the plane 38 through the notches 42, 44. The wedge 56 is then inserted into the opening formed by the grooves with the wedge sides 57, 58 engaging the angled bottoms of the grooves. Force is then applied to the wedge 56 so as to force the dies 49, 50 apart and apply a separating force along a major portion of the longitudinally opposed interior surfaces of the opening 34. This in turn creates the desired tension across the split planes 38, 39 to develop the cracks 45, 46.
Limitation of the opening movement of the fractured portions of the cap and body after formation of the first crack 45 separating the mating legs may be accomplished in any suitable manner. For example, the ends of the bolt bosses in the mating legs could be clamped or placed within movement restricting jaws that prevent substantial further separation after a crack has been formed. Alternatively, the wedge 56 could be formed or moved in a manner that limits separating movement of the dies to a predetermined limited amount. In this way, bending and the resultant deformation of metal at the separated leg ends of the body and cap are avoided as previously described.
Referring now to FIGS. 7-9 of the drawings, there is shown an engine cylinder block assembly, generally indicated by numeral 60, formed with the methods and means of the present invention. Block 60 includes a main body 61 having, in the illustrated lower crankshaft supporting portion, a plurality of saddle-like webs 62 recessed or bifurcated to form first and second legs 63, 64, respectively. The assembly further includes a plurality of saddle-like bearing caps 66 bifurcated to form legs 67, 68 having ends 70, 71 that respectively engage ends 72, 74 of the block legs 63, 64 at each of the main transverse webs 62 of the crankcase portion.
Outwardly adjacent the legs 63, 64, the lower surface of the crankcase (shown inverted) is provided with longitudinal grooves 75, 76 that provide a break between the outer edges of the legs 63, 64 and the outer mounting surfaces 78, 79 of the cylinder block. As in the case of the connecting rod, the caps 66 and the associated legs 63, 64 of the webs 62 are provided with bolt openings 80 that receive shoulder bolts 82 to maintain the caps in engagement with the block upon assembly.
In manufacture, the block assembly 60 is begun by forming a block body 61 with the bearing caps 66 integral with the webs 62. Finish machining of the block assembly 60 is then completed while the body 61 and its individual webs 62 and associated main bearing caps 66 are integral as shown in FIG. 10.
After complete machining, the caps 66 are separated from their respective webs 62 by a process like that described with respect to the connecting rod embodiment of FIGS. 1-3. That is, force is applied across the pin receiving openings 83 of all the webs simultaneously, or sequentially, in directions perpendicular to the split planes inwardly defined by notches 84, 85. Upon separation of the mating legs on one side of the cap and body, a clamping force is applied to prevent substantial separation of the fractured legs while continued separating force is applied in the opening 83 to fracture the other pair of mating legs. The result is the separated cap and web construction shown in FIG. 11 which, with the addition of body bolts 82 in the bolt openings 80 may be assembled and secured in the manner illustrated in FIGS. 7-9.
FIGS. 12 and 12a illustrate alternative embodiments of the split bearing assemblies 86, 86a, respectively, for supporting crankshafts or other shafts and which may be made by the methods and means of the present invention. In each case, a crankcase is constructed by placing a plurality of prefabricated bearing caps 87, 87a of one material, such as cast iron, in a mold in which the main body 88, 88a of a cylinder block or crankcase is subsequently cast using another material, such as aluminum. The separate components are integrally joined along a preroughened split line and finish machining is completed in the manner previously described. Subsequently, the caps 87, 87a are separated from the main body 88, 88a using fracture separation techniques in accordance with the invention as previously described.
In the FIG. 12 embodiment, the complete cap 87 is formed of one material such as cast iron. In the embodiment of FIG. 12A, a cast iron portion of the cap 87a has a larger recess to receive an inner lining 89 of aluminum, cast with the main body and retained within the cap by projections 90 extending into recesses of the cast iron portion of the cap. Upon separation of the cap from the main body 88a, the lining portion 89 is retained within the cast iron cap 87a and is capable of acting as a bearing surface for lightly loaded shafts and the like.
FIGS. 13 and 14 illustrate a novel separating tool 92 for simultaneously separating the caps from the webs of a multiple-webbed cylinder block. Tool 92 includes a cylindrical body 93 having a longitudinal central opening 94 of rectangular cross-section intersecting longitudinally spaced laterally extending semicircular recesses 95 in which are disposed semicircular die members 96 having mating grooves 98. A longitudinally movable actuator 99 having a plurality of angularly disposed wedge surfaces 100 is received in the opening 94 with its wedge surfaces engaging the slanted bottoms 101 of the die grooves 98.
In operation, the tool 92 is inserted through the bores or openings 83 in the webs of an integral block and cap assembly with the dies 96 positioned within the individual bearing caps. The actuating member 99 is then forced in a direction to cause the wedge surfaces 100 to force the die members 96 outwardly, applying separating forces to all of the bearing caps simultaneously. The caps are, thereby, separated from their respective webs of the cylinder block using the two step fracture separation method previously described.
While the invention has been disclosed by reference to certain preferred methods and embodiments chosen for purposes of illustration, it should be understood that numerous changes could be made within the spirit and scope of the inventive concepts described. For example, changes could be made in the design of the components or in details of the fracture process. In addition, various forms of force applying tools or fixtures could be utilized. Possibilities for the latter include not only mechanical tension applying devices but also advanced technologies such as stress waves excited by sound, magnetic fields, mechanical means, etc. Accordingly it is intended that the invention not be limited to the described methods and embodiments, but that it have the full scope permitted by the language of the following claims.
As to the fracture process, it should be recognized that the clamping step may be accomplished in other ways than by applying a clamping force on the ends of the separated legs as described in the specification. Accordingly, any method whereby the separated pair of legs are maintained essentially in their mated positions is to be considered as within the claimed step of "clamping". | Split bearing assemblies are disclosed having separable bearing caps for both single applications, such as connecting rods, and multiple applications, such as engine crankshaft supports, together with methods and apparatus for making such assemblies by integrally forming the caps with the main body and separating them by fracture separation. A two step separation method is disclosed with bore starter notches and semicircular die expanders that minimize split plane and bore distortion. | 5 |
[0001] The present invention relates to a polymerization process wherein at least one diacyl peroxide of formula (I)
is used as a source of free radicals.
[0002] Such processes are known from, for instance, WO 00/17245, where diisobutanoyl peroxide is used to polymerize vinyl chloride by means of the radicals that are formed during the thermal decomposition of the peroxide.
[0003] However, the use of diacyl peroxides of formula (I) can be cumbersome. More particularly, the peroxides of formula (I) are very thermally labile, as a result of which they show significant decomposition during storage at temperatures as low as −5° C. In order to ensure the quality and assay of the product, it is typically produced at temperatures of 0° C. or lower and kept at temperatures of −20° C. during its storage and handling. However, even at such low temperatures, a noticeable reduction of the assay of the material is noted. Furthermore, it is necessary to phlegmatize the peroxides of formula (I), particularly the products wherein R 1 , R 2 , R 3 , and R 4 contain less than 20 carbon atoms in total, using a water-immiscible, hydrophobic solvent, such as isododecane, because the peroxides cannot be handled in the pure form for safety reasons. Such solvents will end up in the polymer made in the polymerization process, which for a variety of well-known reasons (undesired plasticizing of the polymer, exudation from finished polymer articles, which may lead to fogging, and the like), is typically undesired.
[0004] Therefore, there is need for a process wherein peroxides of formula (I) can be used without undesired refrigeration and solvents being obligatory. Preferably, the process also allows the use of water to reduce the safety hazards associated with the diacyl peroxides, so that they can be handled safely during processing and handling/metering to the polymerization reactor.
[0005] Surprisingly, we have found that the use of a specific process for making and using the diacyl peroxides of formula (I) fulfills this need.
[0006] The process according to the invention is characterized in that
an aqueous mixture comprising a peroxide of formula (I) is produced in a peroxidation step wherein i) one or more acid halides of formula (II)
are reacted with ii) MOOH/M 2 O 2 and/or one or more peracids (or their salts) of formula (III)
in an aqueous phase, in which peroxidation step the acid halide, or mixture of acid halides, is essentially only brought into contact with water containing MOOH/M 2 O 2 and/or one or more peracids (or their M salts), to give an aqueous mixture, and iii) optionally one or more colloids and/or surfactants are combined with said aqueous mixture before, during, or after the peroxidation step and the resulting aqueous mixture is used in a polymerization process.
[0014] It is noted that the term MOOH/M 2 O 2 stands for the product that is formed from H 2 O 2 and a suitable source of metal (M) ions. The product typically is not a discrete product M 2 O 2 , but the equilibrium comprising H 2 O 2 , MOOH and M 2 O 2 .
[0015] From an industrial point of view it is preferred that the starting material from which the diacyl peroxides of formula (I) are prepared, i.e. the one or more acid halides of formula (II)
and the one or more peracids (or their M salts) of formula (III)
are easily available or obtainable. Most preferably, these compounds are commercially available.
[0016] The process of this invention is pre-eminently suitable for diacyl peroxides that are liquid at the process temperature, since these diacyl peroxides have a lower hydrolytic and thermal stability than diacyl peroxides that are solid at the process temperature.
[0017] In a preferred embodiment, the aqueous mixture comprising diacyl peroxide of formula (I) is used in the polymerization process within a period of 168, more preferably 102, even more preferably 48, more preferably still 24, yet more preferably 12, yet more preferably still 2 hours after the peroxidation step. In a most preferred embodiment, the reactor wherein the peroxidation step is conducted is directly linked by means of piping and optional further holding or processing tanks to the reactor in which the polymerization process is conducted.
[0018] In another preferred embodiment, the diacyl peroxide is stored and handled in this process at temperatures up to 5° C., since it was observed that, depending on the hydrolytic and thermal stability of the diacyl peroxide, it can be acceptable in the process according to the invention to store and handle the diacyl peroxide up to temperatures of −5° C., preferably 0° C. or more preferably 5° C.
[0019] In the process of the present invention it is necessary to prevent just water and acid halide of formula (II) from being combined at any given time, since otherwise the acid halide would hydrolyze, resulting in low yields of peroxide and causing contamination of the aqueous mixture. Also, a mixture of just water and acid halide was found to be very corrosive, which would require the use of more expensive process equipment. Hence, when it is stated that in the process the acid halide is essentially only brought into contact with water containing MOOH/M 2 O 2 and/or one or more peracids, what is meant is that water and just acid halide are contacted for a period of at most 1 minute, preferably at most 20 seconds, more preferably at most 10 seconds, even more preferably at most 5 seconds, most preferably at most 1 second. Therefore, the only viable ways to make diacyl peroxide are: i) to pre-charge water, MOOH/M 2 O 2 (or, optionally, to make the MOOH/M 2 O 2 from H 2 O 2 and a source of M) and dose acid halide thereto, ii) to pre-charge water and H 2 O 2 and dose both the source of M and acid halide, iii) to pre-charge water and dose both MOOH/M 2 O 2 (optionally H 2 O 2 together with a source of M) and acid halide, and iv) to pre-charge water and a source of M and dose both H 2 O 2 and acid halide. If a peracid is used in the present process, the same viable ways are available (substituting the peracid for H 2 O 2 , and substituting the M salt of the peracid for MOOH/M 2 O 2 ). In order to optimize the yield of peroxide, using one of the four viable ways is preferred.
[0020] It is noted that U.S. Pat. No. 3,923,766 discloses a so-called “in-situ” process where a diacyl peroxide of formula (I) is used that is produced from an anhydride and a peracid. The “in-situ” process is characterized in that the diacyl peroxide is produced in the polymerization reactor in the presence of the monomer, which is not a process according to the invention. Such “in-situ” processes are undesired, since they do not allow a flexible mode of operation. More particularly, most of the peroxide is formed near the start of the process, preventing a constant polymerization rate, and thus resulting in a heat output that is not constant. Such a variation in heat output is undesired, since polymerization reactors are run most cost-effectively under conditions where cooling is at the maximum rate. To overcome this problem, it is suggested in U.S. Pat. No. 3,923,766 to use a second (conventional) more stable initiator. However, such more stable initiators will partially end up in the final polymer, which is undesired for polymer stability reasons (the remaining initiator will lead to premature decomposition of the resin during heat treatment, such as moulding operations).
[0021] U.S. Pat. No. 3,936,506 discloses a method of preparing asymmetrical α-halogen substituted diacyl peroxides of formula (I) wherein R 2 is chloride or bromide, R 4 is hydrogen, and each of R 1 and R 3 is a long chain alkyl radical having about 10 to about 16 carbon atoms. It is noted that these α-halogen substituted diacyl peroxides of U.S. Pat. No. 3,936,506 are not of interest for the present invention, since the starting materials from which these diacyl peroxides are to be prepared are not easily available or obtainable. From an industrial point of view this is an undesirable situation.
[0022] It is furthermore noted that WO 01/32613 discloses a process where peroxy-dicarbonates are produced ex-situ. However, it is desired to offer alternative processes allowing the production of a broader range of peroxides. More specifically, the peroxydicarbonates of WO 01/32613 all have a half-life of 1 hour at a temperature of about 64° C. This means a rather limited freedom when it comes to selecting the polymerization temperature. Also, the chloroformate used to make the peroxydicarbonates is much more hydrolytically stable than the acid halides that are used to make the diacyl peroxides of the present invention. At lower temperatures (say about 50° C.) the peroxydicarbonates will not decompose fast enough to give efficient polymerization times and lead to an unacceptably high residual peroxide content in the final polymer, which adversely affects the thermal stability of the formed polymer. At higher polymerization temperatures (say about 60° C.) the peroxydicarbonates will decompose too quickly, leading to inefficient use and too slow polymerization rates towards the end of the polymerization. Surprisingly, it was found that, after further modification, the concept of WO 01/32613 could be extended to diacyl peroxides of formula (I). The modification needed is, inter alia, to make sure that the acid halide is not just substituted for the chloroformate, but that it is brought into contact with water only when an inorganic peroxide or peracid (salt) is present in the aqueous phase.
DETAILED DESCRIPTION OF THE INVENTION
[0023] The present invention relates to a process comprising the steps of:
producing an aqueous mixture comprising a diacyl peroxide of formula (I)
wherein R 1 -R 4 are independently selected from the group consisting of hydrogen, halogen, and saturated or unsaturated, linear or branched alkyl, alkaryl, and aralkyl moieties optionally substituted with one or more halogen atoms, provided that if R 1 and/or R 2 are hydrogen, then R 3 and/or R 4 are not hydrogen and, vice-versa, that if R 3 and/or R 4 are hydrogen, then R 1 and/or R 2 are not hydrogen, in which process R 1 —C—R 2 and/or R 3 —C—R 4 can be part of a ring structure that can be saturated or unsaturated and substituted with one or more independently chosen groups R 1 , or one of R 1 —C(R 2 )H and R 3 —C(R 4 )H represents an, optionally substituted, aromatic ring structure, by reacting, in a so-called peroxidation step, one or more acid halides of formula (II)
wherein X is halide, preferably chloride or bromide, most preferably chloride, with i) MOOH/M 2 O 2 , wherein M is any metal or ammonium-containing group that will react with H 2 O 2 to form MOOH/M 2 O 2 without decomposing one or more of the peroxides present in the process, preferably M is selected from the group consisting of ammonium, sodium, potassium, magnesium, calcium, and lithium, and/or ii) one or more peracids of formula (III)
or preferably the M salts thereof, in an aqueous phase, in which process the acid halide, or mixture of acid halides, is essentially only brought into contact with water containing MOOH/M 2 O 2 and/or one or more peracids (or their peracid salts), preferably M 2 O 2 or the M salt of the peracid, optionally introducing one or more solvents for the acid halide in any part of the process, optionally introducing one or more salts in any part of the process, optionally introducing one or more colloids and/or surfactants, before, during, or after the peroxidation step, optionally purifying the aqueous mixture in one or more purification steps, optionally homogenizing the aqueous mixture in one or more homogenization steps, transferring the product from the previous steps that comprises the diacyl peroxide of formula (I) to a polymerization reactor, and thermally decomposing said diacyl peroxide, to generate organic free radicals, in the presence of one or more ethylenically unsaturated monomers, to polymerize said monomers in said polymerization reactor.
[0035] In a preferred embodiment, the aqueous mixture comprising said diacyl peroxide is used in said polymerization process within a period of 168, more preferably 102, even more preferably 48, more preferably still 24, yet more preferably 12, yet more preferably still 2 hours after said peroxidation step. In a most preferred embodiment, the reactor wherein the peroxidation step is conducted is directly linked by means of piping and optional further holding or processing tanks to the reactor in which the polymerization process is conducted. Preferably, the diacyl peroxide-containing mixture is prepared just prior to when it is needed in the polymerization step. Should the dispersion be stored for any period of time, then it is preferred, from a safety point of view, to keep the dispersion in motion to prevent phase separation. Any conventional agitation can be used, such as a shaft with blades, a system to bubble inert gas through the dispersion, and/or a recirculation pump. If one or more of the optional colloids and/or surfactants are used in the process, then the diacyl peroxide-containing mixture typically is less prone to phase separation, increasing safety margins.
[0036] In another preferred embodiment, the diacyl peroxide is stored and handled in this process at temperatures up to 5° C., since it was observed that, depending on the hydrolytic and thermal stability of the peroxide, it can be acceptable to store and handle the peroxide in the process according to the invention up to temperatures of −5° C., preferably 0° C. or more preferably 5° C.
[0037] In a further preferred embodiment, the process involves diacyl peroxides of formula (I)
wherein R 1 -R 4 are independently selected from the group consisting of hydrogen, halogen, and saturated or unsaturated, linear or branched alkyl, alkaryl, and aralkyl moieties optionally substituted with one or more halogen atoms, provided that if R 1 and/or R 2 are hydrogen, then R 3 and/or R 4 are not hydrogen and, vice-versa, that if R 3 and/or R 4 are hydrogen, then R 1 and/or R 2 are not hydrogen, in which process R 1 —C—R 2 and/or R 3 —C—R 4 can be part of a ring structure that can be saturated or unsaturated and substituted with one or more independently chosen groups R 1 , or one of R 1 —C(R 2 )H and R 3 —C(R 4 )H represents an, optionally substituted, aromatic ring structure, with the further proviso that diacyl peroxides of formula (I) wherein R 2 is halogen and R 4 is hydrogen, and both R 1 and R 3 are long chain alkyl groups having about 10 to about 16 carbon atoms, are excluded from this invention.
[0038] In yet another preferred embodiment, the process involves diacyl peroxides of formula (I)
wherein R 1 -R 4 are independently selected from the group consisting of hydrogen, halogen, and saturated or unsaturated, linear or branched alkyl, alkaryl, and aralkyl moieties optionally substituted with one or more halogen atoms, provided that if R 1 and/or R 2 are hydrogen, then R 3 and/or R 4 are not hydrogen and, vice-versa, that if R 3 and/or R 4 are hydrogen, then R 1 and/or R 2 are not hydrogen, in which process R 1 —C—R 2 and/or R 3 —C—R 4 can be part of a ring structure that can be saturated or unsaturated and substituted with one or more independently chosen groups R 1 , or one of R 1 —C(R 2 )H and R 3 —C(R 4 )H represents an, optionally substituted, aromatic ring structure, with the further proviso that if R 2 is halogen and R 4 is hydrogen, and both R 1 and R 3 are alkyl groups, then each of these alkyl groups has up to about 6 carbon atoms.
[0039] In yet another preferred embodiment, the process involves diacyl peroxides of formula (I)
wherein R 1 -R 4 are independently selected from the group consisting of hydrogen and saturated or unsaturated, linear or branched alkyl, alkaryl, and aralkyl moieties optionally substituted with one or more halogen atoms, provided that if R 1 and/or R 2 are hydrogen, then R 3 and/or R 4 are not hydrogen and, vice-versa, that if R 3 and/or R 4 are hydrogen, then R 1 and/or R 2 are not hydrogen; in which process R 1 —C—R 2 and/or R 3 —C—R 4 can be part of a ring structure that can be saturated or unsaturated and substituted with one or more independently chosen groups R 1 , or one of R 1 —C(R 2 )H and R 3 —C(R 4 )H represents an, optionally substituted, aromatic ring structure.
[0040] In yet another preferred embodiment of this invention, the diacyl peroxide of formula (I), when transferred to the polymerization reactor, is always transferred from the previous step in the aqueous phase, with the diacyl peroxide being represented by formula (I)
wherein R 1 -R 4 are independently selected from the group consisting of hydrogen, halogen, and saturated or unsaturated, linear or branched alkyl, alkaryl, and aralkyl moieties optionally substituted with one or more halogen atoms, provided that if R 1 and/or R 2 are hydrogen, then R 3 and/or R 4 are not hydrogen and, vice-versa, that if R 3 and/or R 4 are hydrogen, then R 1 and/or R 2 are not hydrogen, in which process R 1 —C—R 2 and/or R 3 —C—R 4 can be part of a ring structure that can be saturated or unsaturated and substituted with one or more independently chosen groups R 1 , or one of R 1 —C(R 2 )H and R 3 —C(R 4 )H represents an, optionally substituted, aromatic ring structure.
[0041] In one still more preferred embodiment only one reactor is used to produce the diacyl peroxide. Most preferably, only one reactor is used to react both the source of M and H 2 O 2 and to carry out the peroxidation step to make the diacyl peroxide.
[0042] The amount of diacyl peroxide (which acts as an initiator) to be used as a source of free radicals in the polymerization step according to the invention is within the range conventionally used in polymerization processes. Typically, from 0.005 to 2% by weight (% w/w) of initiator, preferably 0.01-1% w/w, more preferably 0.01-0.5% w/w, based on the weight of the ethylenically unsaturated monomer(s) to be polymerized, is used. It is noted that the diacyl peroxide initiator of the present invention may be used in combination with other initiators.
[0043] Preferably, the acid halide of formula (II) is derived from C 1 -C 30 carboxylic acids, preferably from isobutanoic acid, 2-methylbutanoic acid, 2-methylpentanoic acid, 2-methylhexanoic acid, 2-methylheptanoic acid, octanoic acid, 2-methyloctanoic acid, decanoic acid, 2-methylnonanoic acid, tetradecanoic acid, hexadecanoic acid, octadecanoic acid, lauric acid, 2-ethylbutanoic acid, 2-ethylpentanoic acid, 2-ethylhexanoic acid, 2-ethylheptanoic acid, 2-ethylnonanoic acid, 2-propylcaprylic acid, 2-propylheptanoic acid, 2-propylhexanoic acid, 2-propyloctanoic acid, 2-propylpentanoic acid, 2-propyl-4-pentanoic acid, 2-butylcaproic acid, 2-butyl-heptanoic acid, 2-butyloctanoic acid, (substituted) cyclohexane carboxylic acid, chloroacetic acid, 2-chloropropionic acid, 2-chlorobutanoic acid, 2-chlorohexanoic acid, dichloroacetic acid, propanoyl-C 16 acid, and aromatic acids such as benzoic acid, 2-chlorobenzoic acid, 3-chlorobenzoic acid, 2-methylbenzoic acid, 3-methylbenzoic acid, 4-methylbenzoic acid, naphtoic acid, and toluic acid. More preferably, at least one of the acid halides is selected from isobutanoyl halide, 2-ethylbutanoyl halide, 2-ethylhexanoyl halide, 2-chloropropanoyl halide, dichloroacetic acid halide, lauroyl halide, cyclohexane carbonyl halide, 3-methylcyclohexane carbonyl halide, 2,3 dihalocyclohexane carbonyl halide, benzoyl halide, 2-methylbenzoyl halide, and 2-chlorobenzoyl halide. If so desired, also the acid halides of polycarboxylic acids, with two or more acid moieties, can be used, such as (cyclo) hexyl dicarboxylic acid, phthalic acid (any isomer), maleic acid, fumaric acid, 1,2,4-butanetricarboxylic acid, (oligomeric) polyacrylic acid, and copolymers with maleic anhydride derivable acid groups. Suitably, a mixture of any of these acid halides is used, typically resulting in a mixture of three or more diacyl peroxides of formula (I), as is known in the art.
[0044] If the acid halide of formula (II) is reacted with a peracid of formula (III), or the salt of such a peracid, wherein R 3 and R 4 are not hydrogen, then also acid halides of formula (II) can be used wherein R 1 and/or R 2 are hydrogen. Examples of such acid halides include chloroacetic acid halide, chloropropionic acid halides (all isomers), acetyl chloride, propionyl chloride, butanoyl chloride, pentanoyl or valeroyl chloride, decanoyl chloride, lauroyl chloride, malonyl chloride, succinoyl chloride, glutaroyl chloride, adipoyl chloride, azeloyl chloride, sebacoyl chloride. Most preferably, the diacyl peroxide produced is diisobutanoyl peroxide.
[0045] The M 2 O 2 is preferably prepared by combining hydrogen peroxide and NaOH, KOH, K 2 CO 3 , and/or Na 2 CO 3 . The M 2 O 2 can be prepared separately or in a reaction step of the present process.
[0046] Any peracid used can be prepared in a conventional way. Preferably, a C 2 -C 20 peracid is used. It is noted that when a peracid is reacted with acid halide, typically an asymmetrical diacyl peroxide is obtained, meaning that R 1 and R 2 are not the same as R 3 and R 4 , whereas if a mixture of two different acid halides is reacted with MOOH/M 2 O 2 , a statistical mixture of two symmetrical and one asymmetrical diacyl peroxides is obtained. The use of a peracid allows better control of the polymerization rate, since just one product with a dedicated half-life time is formed. Furthermore, it is noted that if asymmetrical diacyl peroxide is desired of which R 3 or R 4 is hydrogen, the use of a mixture of acid halides will partially result in the formation of diacyl peroxide that shows no branching on the two α-carbons (relative to the diacyl peroxide function). Such α-carbon unbranched diacyl peroxides are quite stable and part of them will end up in the final polymer, typically resulting in a lower than desired heat stability of the polymer. Hence, it is preferred to use a peracid if it is desired that R 3 and/or R 4 are hydrogen. More preferably, the peracid is selected from the group consisting of peracetic acid, perpropionic acid, perisobutanoic acid, perhexanoic acid, perbenzoic acid, 3-chloroperbenzoic acid, and perlauric acid, the use of perpropionic acid and perlauric acid being most preferred.
[0047] Preferably, the process is conducted such that it is essentially free of solvent, since such solvents are not desired in the final polymer. For the purpose of this specification, essentially solvent-free means that less than 20% w/w of solvent, based on the weight of the diacyl peroxide, is present. Preferably less than 10% w/w, more preferably less than 5% w/w, most preferably less than 2% w/w of solvent is present, all based on the weight of the diacyl peroxide. However, if the use of certain solvents, such as conventional plasticizers for PVC or phlegmatizers for the peroxide, is acceptable in the polymer obtained in the polymerization step, it may be advantageous to use such solvents. Conventional plasticizers include epoxidized soybean oil, dialkyl esters, such as alkyl esters of aliphatic carboxylic acids with two or more carboxylic acid moieties, and less desired phthalate esters. Conventional phlegmatizers include hydrocarbons, such as isododecane.
[0048] Preferably, the peroxidation step of the process is conducted without a salt being added to the reaction mixture. However, if so desired, a salt may be added, for instance to increase the yield of diacyl peroxide. If used, the salt is preferably selected from alkali and/or alkaline-earth metals. Preferably, they are salts of strong acids that do not react with H 2 O 2 , peracid, or a salt thereof. More preferably, the salt is selected from NaCl, KCl, Na 2 SO 4 , K 2 SO 4 , and NH 4 Cl.
[0049] If used, the colloids are advantageously selected from the group consisting of hydrolyzed polyvinyl acetate, alkyl cellulose, hydroxyalkyl alkyl cellulose, gelatin, polyvinyl pyrrolidone, polyoxyethylene sorbitan monolaurate, and polyacrylic acid. Preferably, said dispersant is a non-ionic compound. Most preferably, it is a mixture of one or more hydrolyzed polyvinyl acetates (PVA). Suitably, the degree of hydrolysis of the PVA ranges from 50 up to 95%, preferably up to 90%. Preferably, the degree of hydrolysis is at least 55%, more preferably at least 60%, so that the PVA is soluble in the diacyl peroxide-containing mixture. In order to increase the solubility of the PVA, it can be advantageous to add a C 1 -C 4 alcohol, preferably methanol, ethanol, and/or isopropanol.
[0050] All conventional surfactants can be used. However, in order not to disturb the dispersion of the polymerization reaction and not to adversely affect the properties of the final polymer, the surfactant preferably is a (biodegradable) cationic compound, such as preferred quaternary ammonium compounds, or a non-ionic surfactant. Preferred conventional non-ionic surfactants include, but are not limited to, alkoxylated (fatty) alcohols and alkoxylated sugars.
[0051] The aqueous mixture that results from the peroxidation step can be transferred to the polymerization reactor “as is”. However, in order to enhance the safety of handling of the diacyl peroxide, it is preferred to add at least one surfactant and/or colloid, so that a physically stable dispersion of the diacyl peroxide in the aqueous mixture, or a dispersion of the aqueous phase in the diacyl peroxide, is obtained. If need be, the size of the dispersed phase (droplet or particle size) can be reduced in an optional further homogenization step. However, such a step is only a prerequisite when the dispersion as obtained is not safe. Suitably, this is detected by heating a 100 g sample of the dispersion up to a temperature where the diacyl peroxide decomposes. If a certain phase separation is observed, the safety characteristics of the least safe phase are decisive. However, it may also be desired to obtain a very finely dispersed phase, for instance to enhance an even distribution of the diacyl peroxide over the monomer(s) in the polymerization reactor (e.g. to reduce the fish-eye level in PVC that is produced by a suspension polymerization process). If such fine dispersions (with the average size by volume of the dispersed phase being less than 10 μm, preferably less than 5 μm, most preferably less than 2 μm) are of interest, then also an extra homogenization step can be advantageously introduced. The homogenization step can be performed using any suitable (high) shear mixer, such as rotor/stator homogenizers, colloid mills, ultrasonic devices, and the like.
[0052] In a preferred embodiment, the diacyl peroxides of this invention are prepared in a feed line, such as a pipe, that is directly connected to the polymerization reactor. The desired (raw) materials for the peroxidation step are then fed into the pipe at suitable points. Optionally, an in-line mixer is then used to homogenize the resulting product of the peroxidation step before it is used in the polymerization step. If so desired, part of the product of the peroxidation step may be recycled in such a set-up to increase the yield of diacyl peroxide. If so desired, the line may be flushed clean with water after the peroxidation step. However, it can also be switched to another polymerization reactor, such that the peroxidation can be an essentially continuous operation.
[0053] The product resulting from the peroxidation step typically contains by-products and residual raw materials. Particularly when the diacyl peroxide is prepared using MOOH/M 2 O 2 , a substantial quantity of a salt (MX) is formed. The by-products must not be a hindrance in the polymerization reaction. However, it is known that salts adversely affect the stability of the emulsion of the diacyl peroxide, which is a safety concern, while salts may also adversely affect the electrical properties of the final polymer. Hence, it may be preferred to include a purification step. Depending on safety considerations, it can be acceptable to conduct the peroxidation step without any surfactants and/or colloids being used and then to separate and discard (part of) the water layer, after which the diacyl peroxide-rich organic layer may be dispersed and/or diluted, if so desired, using the appropriate media and/or solvents. If an aqueous diacyl peroxide dispersion is to be achieved, conventional surfactants and/or colloids can be used in the dispersion step. Alternatively, (part of) the salt may be removed using conventional techniques, such as (reverse) osmosis, nanofiltration, ion-exchange, precipitation, and the like. A less preferred process would involve a step wherein a conventional solvent for the diacyl peroxide is added to extract the diacyl peroxide from the mixture.
[0054] The process according to the invention is pre-eminently suited to polymerize one or more ethylenically unsaturated monomers, including (meth)acrylic acid (esters), styrene, vinyl acetate, acrylonitrile, vinyl chloride monomer (VCM), and the like. Preferably, the process according to the invention involves the polymerization of monomer mixtures comprising at least 50% w/w of VCM, based on the weight of all monomer(s). In this preferred process, preferred comonomers for use are of the conventional type and include vinylidene chloride, vinyl acetate, ethylene, propylene, acrylonitrile, styrene, and (meth)acrylates. More preferably, at least 80% w/w of the monomer(s) being polymerized is made up of VCM, while in the most preferred process the monomer consists essentially of VCM. As is known in the art, the polymerization temperature of such processes determines to a large extent the molecular weight of the final polymer.
[0055] The polymerization process can be conducted as a mass process where the reaction mixture is predominantly monomer(s) or as a suspension process where the reaction mixture typically is a suspension of monomer(s) in water, or as an emulsion or micro-emulsion process where the monomer(s) typically is/are emulsified in water. In these processes the usual additives will have to be used. For example, if the monomer(s) is/are present in the form of a suspension in water, the usual additives such as surfactant(s), protective colloid(s), anti-fouling agent(s), pH-buffer(s), etc. may be present. Depending on the type of polymer desired, each of the abovementioned processes may be preferred. The process according to the invention is especially suited for mass and suspension processes. In the aqueous suspension process to produce PVC from VCM, the polymerization is usually conducted at a temperature in the range of about 0° C. to 100° C. However, for the process of the present invention it is preferred to employ polymerization temperatures of about 40° C. to about 70° C., since this is the temperature at which VCM is polymerized efficiently. The polymerization reaction time may vary from about 1 to about 15 hours, and is preferably from 2 to 6 hours. The aqueous suspension VCM polymerization process in addition to the VCM typically contains water, dispersants, free radical initiator, and optional further ingredients, such as buffers, short stop agents, pre-stabilizers, and the like.
[0056] After the polymerization, the resulting (co)polymer (or resin) will be worked up as is usual in the art. Polymers obtained by a suspension polymerization according to the invention, for example, will be submitted to the usual drying and screening steps. The resulting resin preferably is characterized in that it contains less than 50 ppm of residual diacyl peroxide, more preferably less than 40 ppm, and most preferably less than 25 ppm of diacyl peroxide, immediately after drying for 1 hour at 60° C. and screening. The resin was found to exhibit excellent heat stability, as measured with a Metrastat® PSD260 testing oven in accordance with ISO 182-2 (1990E). The improved heat stability proved that the resin hardly discoloured when submitted to melt-processing steps, e.g., to form shaped articles.
[0057] The process according to the present invention is pre-eminently suited for combination with polymerization processes as disclosed in WO00/17245. Accordingly, a preferred embodiment of the present invention relates to a process of claim 1 wherein at least part of the diacyl peroxide is dosed to the polymerization mixture at the reaction temperature. More preferably, essentially all of the organic initiator, i.e. diacyl peroxides and, if used, other conventional initiators, dosed in the polymerization process has a half-life of from 0.0001 hour to 1.0 hour at the polymerization temperature, preferably from 0.001 to 0.8 hour, more preferably from 0.002 to 0.5 hour at the polymerization temperature. If the one or more diacyl peroxides are dosed together with other initiators, it is preferred that the diacyl peroxide(s) as well as all other initiators fulfill these half-life requirements. It is noted that half-lives are determined in conventional thermal decomposition studies in monochlorobenzene, as is well-known in the art (see for instance the brochure “Initiators for high polymers” with code 10737 obtainable from Akzo Nobel).
[0058] The dosing of the extremely fast initiators to the polymerization reaction mixture can be intermittent or continuous over a period of time wherein at least 20%, preferably at least 40%, more preferably at least 60% of all monomer used in the process is polymerized. If an intermittent operation is selected, there are at least 2, preferably at least 4, more preferably at least 10, and most preferably at least 20 moments at the polymerization temperature at which the initiator is dosed. If so desired, the intermittent and continuous operations may be combined, such that the initiator is dosed intermittently for certain (longer or shorter) periods of time. Most preferably, the diacyl peroxide is dosed continuously and/or intermittently after at least 5%, preferably at least 10%, more preferably at least 20%, most preferably at least 30% of the monomer(s) has already been polymerized and while during the dosing period at least 10%, preferably at least 20%, more preferably at least 30%, and most preferably at least 50% of all monomer used in the process is polymerized.
[0059] Preferably, the diacyl peroxide is dosed in a concentration of 0.1 to 60% w/w, more preferably 0.5 to 25% w/w, and most preferably 2 to 15% w/w, based on the weight of the diacyl peroxide-containing mixture, in order to facilitate the even distribution of the diacyl peroxide over the monomer.
[0060] The dosing can be effected at any suitable entry point to the reactor. If water is added in the course of the polymerization process, for example to compensate for the shrinkage of the reactor content due to the polymerization reaction, it may be advantageous to use the line through which this water is dosed to also dose the initiator. In a most preferred embodiment, the diacyl peroxide has also been produced in said line.
EXPERIMENTAL
[0061] The following chemicals were used in the process to manufacture diacyl peroxides. It is noted that all experiments were performed taking sufficient safety measures. In this respect it is also noted that pure diisobutanoyl peroxide is a detonatable explosive.
[0062] Commercially available aqueous H 2 O 2 with an assay of 69.97% was used.
[0063] NaOH solution (NaOH-25 and NaOH-33) containing 25% w/w and 33% w/w, respectively, of NaOH was produced from Baker-grade NaOH and distilled water.
[0064] NaCl solution (NaCl-15 and NaCl-25) containing 15% w/w and 25% w/w, respectively, of NaCl was produced from Baker-grade NaCl and distilled water.
[0065] Na 2 CO 3 solution containing 10% w/w of Na 2 CO 3 was produced from Baker-grade Na 2 CO 3 and distilled water.
[0066] HCl solution containing 18% w/w of HCl was produced from Baker-grade HCl and distilled water.
[0067] Isobutanoyl chloride (99.3%) was supplied by BASF
[0068] Lauroyl chloride (98%/o) was supplied by Acros.
[0069] A fresh PVA solution, 5% w/w Alcotex® 72.5 ex Harco in demineralized water was prepared fresh, 1 day prior to use.
Example 1
[0070] For the preparation of isobutanoyl-lauroyl peroxide, a reactor was charged at 0° C. with 35 g deionized water, 286 g NaCl-25 solution, 110 g of Na 2 CO 3 solution, 39 g NaOH-25 solution, and 32.5 g H 2 O 2 solution. Then, within 50 minutes 103.0 g isobutanoyl chloride were dosed while maintaining a pH-value of 11.0 with the aid of NaOH-25 solution. The temperature was maintained at 0° C., and meanwhile the contents of the reactor were homogenised. After addition of the total amount of isobutanoyl chloride, the reaction mixture was stirred for another 15 minutes at pH 11.0. Then, the pH was lowered to 10.0 with HCl solution and the temperature was brought to 5° C. Next, 70.5 g lauroyl chloride were dosed over a period of 10 minutes, while maintaining the pH on 10.0 with the aid of NaOH-25 solution. After addition of the total amount of lauroyl chloride, stirring was continued for another 15 minutes.
[0071] The reaction mixture was set aside for 30 minutes in order to allow the two-phase system to separate. The aqueous layer was removed (713 g) and the organic peroxide layer was washed with 300 g NaCl-15 solution. Again, the aqueous layer and the organic layer were allowed to separate, in order to facilitate the isolation of the peroxide layer (Isolated yield: 145.0 g).
[0072] Analysis of the isolated peroxide layer:
35% diisobutanoyl peroxide 64% isobutanoyl-lauroyl peroxide <1% dilauroyl peroxide <0.01% acid chloride
Example 2 and Comparative Examples A-D
[0077] In Example A, the procedure of WO 01/32613 was repeated. First, a solution of Na 2 O 2 was prepared by combining 108.3 g of demineralized water, 18.5 g of NaOH-33 solution, and 3.7 g of the aqueous H 2 O 2 . A second reactor was charged with 33.3 g of demineralized water, 27.7 g of the PVA solution, and 16.3 g of isobutanoyl chloride while controlling the temperature between 5-10° C. Next, the Na 2 O 2 solution was dosed while the system was homogenized. No diisobutanoyl peroxide was obtained and only an aqueous phase formed.
[0078] In Example B, the same procedure was followed as in Example A, except that 2-ethylbutyroyl chloride was used instead of the isobutanoyl chloride. Again, no diacyl peroxide was obtained.
[0079] In Example C, the same procedure was followed as in Example A, except that 2-ethylhexanoyl chloride was used instead of the isobutanoyl chloride. Again, no diacyl peroxide was obtained. The resulting mixture was milky white, probably because a lot of 2-ethylhexanoic acid was formed which did not all dissolve in the water.
[0080] In Example D, the procedure of Example A was modified in that the second reactor was charged with all the water, PVA solution, isobutyroyl chloride, and aqueous H 2 O 2 , and the NaOH-33 solution was then dosed to it at a temperature of 5-10° C. The yield of diisobutanyl peroxide is expected to be less than 20% w/w.
[0081] In Example 2, a single reactor was charged with 141.5 g of demineralized water, 18.5 g of NaOH-33 solution, 27.7 g of PVA solution, and 3.7 g of the aqueous H 2 O 2 , after which 16.3 g of isobutanoyl chloride were dosed to the contents of the reactor, while maintaining a temperature of 5-10° C. and while homogenizing the contents of the reactor. An emulsion resulted. The yield of diisobutanoyl peroxide was 82% w/w. It is expected that if the emulsion is used within 48 hours in a polymerization reaction, it will show the same polymerization rates for VCM as were observed when using the same amount of a conventional 30% w/w diisobutanoyl peroxide solution in isododecane.
Example 3
[0082] The product of Example 2 was stored for 1.5 hours at 5° C. without being stirred. The active oxygen content (a measure of the amount of diacyl peroxide of formula (I)) of the emulsion was reduced by 2.5% and a little phase separation occurred. In Example 3, a reactor was charged with 175 g of demineralized water, 16.4 g of NaOH-33 solution, 43.8 g of NaCl-25 solution, 250.5 g of Na 2 CO 3 solution, and 4.8 g of the aqueous H 2 O 2 . Then 23.1 g of isobutanoyl chloride was dosed to the contents of the reactor, while maintaining a temperature of 5-10° C. and homogenizing the contents of the reactor. At the end of the reaction the mixture was neutralized to pH=7. Taking sufficient safety measures, the two-phase system was allowed to separate and about 70% by volume of the aqueous phase was removed. To the organic layer and the remainder of the water layer were added 207.2 g of demineralized water, 109.3 g of PVA solution, 13.7 g of methanol, and 21.9 g of an aqueous 0.2% w/w Berol® 08 (non-ionic emulsifier ex Akzo Nobel) solution. A dispersion resulted which was stable for more than 2.5 hours and showed good performance in the polymerization process of VCM. The yield of diisobutanoyl peroxide was 86% on isobutanoyl chloride and 93% on H 2 O 2 . | The invention relates to a process to make and use specific diacyl peroxides in polymerization reactions. The peroxides are produced and used in a polymerization process within a short timeframe in order to overcome stability issues associated with them. | 2 |
BACKGROUND OF THE INVENTION
Field of the Invention
The invention relates to a method for the characteristic map-based obtention of values for at least one control parameter of an installation, particularly an internal combustion engine, whereby support points for the control parameter, which provide a value for the control parameter, are defined across a range of operational parameters within a characteristic map in accordance with operational parameters of the installation.
For installations, in particular for internal combustion engines, it has long been known to store control parameters in characteristic maps so that an optimal value can be obtained for the control parameter for a current operating point according to the most varied input quantities, such as, for example, speed, load, operating temperature, oil temperature.
For internal combustion engines that can be run in different discrete operating modes, i.e. where one can choose between different operating modes, it is usual to have a characteristic map ready for each operating mode, which map is specific to and optimized for the respective mode. Then when an operating mode is changed, there is a switch over to the characteristic map specific to the operating mode, so that this characteristic map will be accessed in the further operation of the internal combustion engine, in any event as long as the assigned operating mode continues. An example for such an operating mode change can be found in internal combustion petrol engines, which can be run in stoichiometric or various lean operating modes. Normally there are three known operating modes for such internal combustion engines, that is to say, stoichiometric, uniform-lean and stratified-lean.
A further internal combustion engine type which allows several operating modes, are internal combustion diesel engines, whereby fuel is injected from a high pressure reservoir (common-rail injection system). There, the fuel quantity injected for a work cycle can be distributed practically at will into single (shot) injections. In this context, one talks about pre, main and post injections. The flexibility of the design of an injection process effects very many different operating modes for such internal combustion engines, each modes being characterized by the distribution of the fuel quantity per work cycle in the above mentioned injections. As each operating mode must have its own characteristic map held ready, the memory requirement for operating control units of internal combustion engines of this type is greatly increased. Furthermore the application, i.e. the adaptation of an internal combustion engine control structure to a current internal combustion engine model, becomes relatively complex with the plurality of characteristic maps.
SUMMARY OF THE INVENTION
The object of the invention is therefore to provide a method for the characteristic map-based obtention of values for at least one control parameter of an installation of the type cited above, whereby the memory requirement can be kept as low as possible even if there are many different operating modes.
This task is achieved according to the invention by a method for the characteristic map-based obtention of values for at least one control parameter of an installation, particularly an internal combustion engine, whereby support points for the control parameter, each of which provide a value for the control parameter, are defined across a range of operational parameters within a characteristic map in accordance with operational parameters of the installation, the range of operational parameters covered in said characteristic map is divided into a first and a second subdomain which comprises several of the support points, and the value for the control parameter is obtained by extrapolation when a boundary of the first subdomain is reached before the value for the control parameter is obtained by accessing support points of the second subdomain.
Thus the invention departs from the previous approach of providing a specific characteristic map for each operating mode and instead uses subdomains in characteristic maps. As a change from one subdomain to the next corresponds in prior art to the switching between individual characteristic maps, but regularly involves a non continuous change in the value of the control parameter, which change is, it is not possible to simply change from one subdomain to the next, as that would result in a jump. When operating at the boundary of the subdomain, this would lead to continual jumps, this being incompatible with smooth control of the installations.
A hysteresis is achieved by means of the extrapolation according to the invention across the subdomain, which nevertheless results in a continuous, uniform and fault free installation operation despite the transition of the control parameter values at the subdomain boundaries not being constant, even when there are operating points at boundaries of subdomains over a longer period of time. The obtention of values for the control parameter within the subdomains is carried out by the standard method, i.e. by evaluating the support points and possibly suitable interpolation.
Thus the invention carries out a standard interpolation between support points within a subdomain, and in the case of support points at subdomain boundaries, i.e. in the case of support points that are adjacent to other subdomains, the invention carries out an extrapolation based on that support point. By means of the extrapolation, the transitions between the subdomains are cleanly separated and at the same time a memory, in which the characteristic map is held ready, is optimally utilized.
The hysteresis provided for the transition between the two subdomains is in principle already achieved by the fact that an extrapolation occurs starting from a subdomain. A particularly large hysteresis, and hence one resulting in stable operating behavior of the installation, is achieved, however, by effecting an initial extrapolation also after a change of subdomain. It is therefore preferable that when a certain distance from the last support point of the first subdomain is reached, the value is obtained by extrapolation from support points of the second subdomain.
In principle the number of subdomains can be chosen at will, a person skilled in the art will select this in accordance with the operating behavior of the installation. It is particularly preferable for internal combustion engines in particular, that a (discrete) operating mode of the installation is assigned to each subdomain. A one-to-one correspondence between subdomain and operating mode then makes it possible for a single characteristic map to suffice for all operating modes of the installation.
The method according to the invention is especially advantageous with the internal combustion engine type mentioned above, in which engine fuel is injected directly into combustion chambers and the discrete operating modes are differentiated by the number of injections per work cycle. The internal combustion diesel engines mentioned that have direct injection from high pressure reservoirs provide an example of such internal combustion engines.
In the case of internal combustion engines with direct injection, the quantity of fuel that is introduced into the combustion chambers with the main injection is an important parameter for controlling the operation of the internal combustion engine. A further injection parameter is the time of the injection. Therefore, it is especially preferred that the characteristic map contains values of injection parameters in accordance with speed and load of the internal combustion engine, whereby the injection parameters can include injection quantity and/or injection angle.
The 1:1 assignment mentioned, between subdomains of the characteristic map and operating modes of the internal combustion engine, has the advantage that an application, i.e. an adaptation of a control structure to an internal combustion engine model, is especially simple. It then possible to control the internal combustion engine in such a way that when the stated specific operating state is reached, i.e. when a boundary of a subdomain is reached, simultaneously a change of the operating mode is carried out. Then, the subdomain of the characteristic map which is assigned to the respective operating mode is always accessed in order to obtain the values of the at least one control parameter.
The invention is described in more detail below with reference to the drawing by way of example in which;
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a block diagram of an internal combustion diesel engine with high pressure reservoir injection,
FIGS. 2-5 shows time sequences of the process of an injection for a work cycle of a cylinder in an internal combustion engine of FIG. 1 ,
FIG. 6 shows a schematic representation of a characteristic map for the operation of the internal combustion engine in FIG. 1 ,
FIG. 7 a flow chart for the obtention of control parameter values in the internal combustion engine in FIG. 1 ,
FIG. 8 a model cycle through the characteristic map in FIG. 6 in an operational phase at a constant speed and
FIG. 9 the values for a control parameter obtained during the cycle in FIG. 8 .
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a schematic representation of an internal combustion engine 1 , which has a injection system 2 , which injects the fuel directly into the combustion chambers of the internal combustion engine 1 via (not shown in detail) lines and injectors. The injection system 2 has a high pressure accumulator, which feeds injectors leading into the combustion chambers of the internal combustion engine 1 . These injectors of the injection system 2 can be controlled independently of the rotational position of a crankshaft of the internal combustion engine 1 , so that it is possible to freely control the injection discharge rate from the high pressure accumulators.
A control device 3 controls both the internal combustion engine 1 and the injection system 2 , said control device being connected to these units via lines (not shown in detail). The control device 3 has a characteristic map 4 and a control core 5 , which control the operation of the internal combustion engine. Values for the duration of injection as function of the speed and load of the internal combustion engine are stored in the characteristic map 4 (which is detailed further later), the characteristic map having several support points, each of which provide a value for the injection quantity for a specific combination of load/speed.
The control device 3 naturally has other characteristic maps and control elements, which are, however, of no further relevance for the following description for the characteristic map-based obtention of values for a control parameter.
The control device 3 controls the injection system with respect to the duration the injectors are active. Thereby, as already mentioned, different injection discharge rates can be set for a work cycle. For example, the control device 3 of the internal combustion engine 1 can realize the injection discharge rates illustrated in FIGS. 2 to 5 . In FIGS. 2 to 5 , a fuel quantity rate MF over the time t is illustrated in each injection discharge rate 6 .
FIG. 2 shows a first operating mode M 1 , in which the injectors only deliver one main injection 7 . Thereby, a fuel quantity 8 of the main injection 7 results from the integration of the fuel quantity rate MF over the time t of the main injection 7 .
FIG. 3 shows another mode M 2 , which differs from the mode M 1 in the fact that the main injection 7 precedes a pre-injector 9 . Thereby, in the main injection 7 the fuel quantity 8 is delivered, and a fuel quantity 10 is delivered by the pre-injector 9 . Normally, such pre-injectors are used to make combustion proceed “softly” and to reduce the operating noise of an internal combustion engine.
A further reduction in noise is produced in a mode M 3 , illustrated in FIG. 4 . Here an additional pre-injector 11 precedes the pre-injector 9 , and said pre-injector 11 injects a fuel quantity 12 into the combustion chamber. Otherwise mode M 3 corresponds to mode M 2 .
The great flexibility that the injection system supplied from a pressure reservoir allows is shown in FIG. 5 in which a further mode M 4 is illustrated. In this mode, in addition to the main injection 7 , which feeds the fuel quantity 8 into the combustion chamber, and to the pre-injector 9 , which contains the fuel quantity 10 , a post injector 13 with a fuel quantity 14 is delivered after the main injection 7 . Using such a post injector produces an increase in torque at low speeds.
As can be clearly seen, in the operation of the internal combustion engine 1 , only one of the modes M 1 to M 4 can be executed at a time. The control device 3 therefore effects an appropriate mode switch, which is triggered by control core 5 , which has recourse to the characteristic map 4 and ensures that the internal combustion engine 1 is always running in the most appropriate operating mode M 1 to M 4 . Thereby, the control core 5 accesses the characteristic map 4 , schematically represented in FIG. 6 , in order to select or determine the fuel quantity 8 of the main injection 7 .
FIG. 6 shows the basis of the characteristic map 4 , which extends over the speed N and the torque TQI. The shaded areas of the characteristic map 4 contain support points, each of which provides a value for the fuel quantity 8 . In a three dimensional interpretation of the characteristic map 4 the support points would be vectors running perpendicular to the plane of projection, the length of which vectors specifies the fuel quantity 8 . Thereby, the support points (not drawn in FIG. 6 ) are distributed across the shaded areas of the characteristic map 4 , the distribution being normally, though not necessarily, equidistant. Thus a higher support point density can be planned for certain operational areas, in particular where speeds are low.
The characteristic map 4 has four subdomains T 1 to T 4 , which are allocated to the respective operating modes M 1 to M 4 . The diagrammatic view in FIG. 6 differentiates the subdomains by the shading. The subdomains border on each other in transition areas 15 to 18 , whereby the transition area 15 separates the subdomains T 2 and T 3 (corresponding to the modes M 2 and M 3 ), the transition area 16 separates the subdomains T 2 and T 4 (corresponding to the modes M 2 and M 4 ), the transition area 17 separates the subdomains T 3 and T 4 (corresponding to the modes M 3 and M 4 ) and the transition area 18 separates the subdomains T 1 and T 2 (corresponding to the modes M 1 and M 2 ) from each other. There are no support points in the transition areas 15 to 18 , which are symbolized by thicker black lines in FIG. 6 .
To achieve a smooth running of the internal combustion engine when the internal combustion engine 1 is operated near or in the vicinity of one of the transition areas 15 to 18 , the transition areas 15 to 18 are used to execute a hysteresis, as represented in FIG. 7 as a flow chart.
First in a step S 0 , the internal combustion engine is started with defined subdomain and defined mode, for example, subdomain T 3 and mode M 3 . The values for the fuel quantity 8 are then obtained within this subdomain by an interpolation between the support points; this occurs in step S 1 . By interpolation it is also understood, of course, that in the event that speed N and torque TQI are exactly at a support point, exactly the value supplied by the support point is used for the fuel quantity 8 . Thereby, the internal combustion engine is operated in the operating mode M 3 , i.e. two pre-injectors 9 and 11 are executed and the main injection 7 lasts so long that the fuel quantity supplied by the subdomain T 3 of the characteristic map 4 is delivered by the fuel quantity 8 .
After each obtention of a value for the fuel quantity 8 , in a step S 2 it is queried whether the operating point is in a transition area. This query can be carried out by checking whether there is a further support point within the subdomain for the active mode, beyond the current operating point, i.e. in the direction in which the dynamic of the operation of the internal combustion engine indicates a development of speed N and torque TQI. If this is not the case, there is an operation in the transition area. If there is no transition area (N branch) then a jump back is made before step S 1 .
If, on the other hand, there is a transition area (J branch) step S 3 is continued with, in which step there now occurs an extrapolation with recourse to the support points of the subdomain T 3 to find the value for the fuel quantity 8 of the main injection 7 .
After each extrapolation, a step S 4 queries whether a hysteresis distance H exceeds a threshold value SW. In this way a check is made as to whether the distance from the last support point of the active subdomain, which is valid for the current mode, exceeds the threshold value SW, i.e. it is checked whether there is (still) an operation in the transition area. If this is not the case (N branch) a jump back is made before step S 2 .
Nevertheless if the hysteresis distance H has exceeded the threshold value SW, i.e. if a certain minimum distance from the nearest support point of the active subdomain is reached, then step S 5 (J branch) is continued with, said step effecting a change of the operating mode. Thereby, the change occurs into the mode which has the nearest support point in relation to speed N and torque TQI. Exceeding the threshold value of the hysteresis distance H, thereby ensures that this query delivers an unequivocal result and hence the determination of the operating mode now to be used.
After the operating mode and thus also the relevant subdomain was changed in step S 5 , step S 1 comes in again, i.e. the determination of the fuel quantity 8 is made again by interpolation in the now current subdomain of the characteristic map 4 . If an interpolation is not possible, an extrapolation can possibly also be carried out analogously to step S 3 .
The choice of the threshold value SW for the hysteresis distance H ensures that, in any case, support points of the now current subdomain are closer than those of the subdomain that has just been left.
FIGS. 8 and 9 show the process described using FIG. 7 again and in greater detail. FIG. 8 thereby shows a section from the characteristic map 4 in FIG. 6 and shows the passage through two operating mode changes at a constant speed. The graph in FIG. 9 shows the associated fuel quantity 8 as a function of the torque TQI.
Operating points B 1 to B 9 are drawn in FIG. 8 and FIG. 9 shows the corresponding data points D 1 , D 2 , E 3 a , E 3 b , D 4 , D 5 , D 6 , E 7 a , E 7 b , D 8 and D 9 which are allocated to said points. The data points marked with D are values obtained by interpolation from the characteristic map 4 or a subdomain of the characteristic map 4 , the data points marked with E are values obtained by extrapolations.
In the process illustrated in FIGS. 8 and 9 , the internal combustion engine 1 is first operated in an operating point B 1 . For reasons of simplicity, a constant speed will be assumed for the following operating point change. By increasing the torque TQI or the requirement for this torque, the internal combustion engine reaches the operating point B 2 , which, like the operating point B 1 is handled in the mode M 3 , in which the subdomain T 3 is accessed. The data point D 2 is obtained for the operating point B 2 from the subdomain T 3 of the characteristic map 4 by interpolation.
By dint of a further torque increase, the internal combustion engine reaches the operating point B 3 , which now lies in the transition area 15 . Thus now (for the first time) the query in step S 2 leads to the J branch. From now on, the fuel quantity 8 is obtained by extrapolation, and hence there is an extrapolated data point E 3 a in FIG. 9 . Further development of the torque TQI results in the hysteresis distance H exceeding the threshold value SW, which is why mode change 19 is carried out, and the internal combustion engine subsequently runs in operating mode M 2 . Thus the additional pre-injector 11 will no longer be delivered.
In operating mode M 2 , the obtention of the value for the fuel quantity 8 is made by extrapolation with recourse to the values of the subdomain T 2 of the characteristic map, so that now an extrapolated data point E 3 b provides the value for the fuel quantity 8 in the operating mode M 2 . The torque increases further and brings the internal combustion engine to the operating point B 4 , for which a read-out data point D 4 gives the value for the fuel quantity 8 of the main injection 7 , and possibly does so by interpolation.
In subsequent torque increases, operating points B 5 and B 6 are reached in operating mode M 2 , and (read-out) data points D 5 and D 6 are allocated to said operating points. The torque TQI continues to rise, this results in an operating point B 7 , which operating point is in a transition area, in this case in the transition area 16 . Here the description given for the transition area 15 applies analogously, i.e. the next value for the fuel quantity 8 is obtained by extrapolation at a data point E 7 a , whereby the support points of the subdomain T 2 , which is allocated to the operating mode M 2 , are used for the extrapolation.
In the moment in which the hysteresis distance exceeds the threshold value (J branch of step S 4 ), there is a mode change 20 , and when the internal combustion engine is operated in mode M 4 , now in addition post injector 13 is delivered. The valid fuel quantity 8 of the main injection 7 for this operating mode is obtained from subdomain T 4 by extrapolation, so that there is an extrapolated data point E 7 b . Further torque increases bring the internal combustion engine to operating points B 8 and B 9 , at which the value for the fuel quantity 8 is obtained using data points D 8 and D 9 . | Disclosed is a method for the characteristic map-based obtention of values for at least one control parameter of an installation, particularly an internal combustion engine. According to the inventive method, support points for the control parameter, which provide a value for the control parameter, are defined across a range of operational parameters within a characteristic map ( 4 ) in accordance with operational parameters of the installation, the range of operational parameters covered in said characteristic map is divided into a first and a second subdomain which comprises several of the support points, and the value for the control parameter is obtained by extrapolation when a boundary of the first subdomain is reached before the value for the control parameter is obtained by accessing support points of the second subdomain. | 5 |
BACKGROUND OF THE INVENTION
The present invention relates to elongated decorative mouldings, for protecting the bodies of land and water vehicles and the like from damage caused by minor impacts. In particular, the invention relates to mouldings of this type which comprise an extruded strip having a decorative strip attached thereto and carrying adhesive means for fastening the moulding to a vehicle body.
Such mouldings have enjoyed increasing popularity since about 1965 among auto body customizers and the automobile-buying public. The growth in popularity of these mouldings was not only because of their decorative qualities but also because they significantly lessen the paint chipping and minor dents inflicted in parking lots by the careless opening of adjacent car doors. More recently, automobile manufacturers such as the Ford Motor Company have been installing such mouldings on their new vehicles for the above reasons and because they did not require fasteners as did the chromed metallic moulding strips which had previously been used on new cars.
In their most popular form, such mouldings are formed by laminating a decorative strip of thin material (for example vinyl or polyvinyl chloride material) to the impact-absorbing surface of a thicker extruded strip of, for example, vinyl or polyvinyl chloride material. The exposed outer surface is typically coated with a metallic material such as aluminum in order to present an attractive chrome-like appearance to the decorative strip. Because the metallic material is susceptible to discolouration due to weathering, it is common to use decorative strips which have a protective polyester film applied over the metallized surface.
In practice, such decorative strips are formed by first metallizing a wide, thin sheet of, for example, polyvinyl chloride material, laminating it with a wide polyester film, and then slitting the metallized, polyester film covered sheet into narrow decorative strips. Unfortunately, slitting causes slight delamination of the polyester film from the metallized surface along the edges of the decorative strips. This "slitting delamination" later permits weathering and discolouration of the metallic decorative material after the decorative strip has been attached to the thick extruded strip to form the finished moulding and the later has been attached by a adhesive to a car body. It is believed that this discolouration is caused by the progressive action oxidation, salt and other corrosive elements of the atmosphere which begin at the edges of the decorative strip and gradually corrode most of the aluminum or other metallic material between the polyester film and the polyvinyl chloride strip. As a result, the decorative strip typically becomes dull and discoloured within about one year after the moulding has been applied to the vehicle body. Such discolouration is very undesirable and gives rise to numerous consumer complaints.
Previous attempts at overcoming this problem have met with little success. The most common approach has been to bury the edges of the decorative strip into the thick extruded strip in order to prevent their exposure to weathering. Unfortunately, this solution is complex, is unsuited to many popular decorative moulding designs, and may even cause delamination of the protective polyester film by the migration of plasticizer compounds from the thick extruded strip into the adhesive used to attach the polyester film over the metallized decorative strip.
Accordingly, it is the principal object of the invention to provide an elongated decorative moulding which is highly resistant to weathering and the attendant discolouration of the metallized or otherwise decorative strips carried by the moulding.
It is a further object to provide a weather-resistant moulding which obviates the need to use expensive decorative strips which have a highly weather-resistant polyester film laminated thereto.
It is a further object to render the moulding weather resistant while permitting production thereof to be carried out with safety at the extrusion rate of the thick extruded strip.
SUMMARY OF THE INVENTION
To achieve the foregoing and other unstated objects and advantages, the present invention provides an elongated decorative moulding for protecting vehicle bodies from minor impacts, said decorative moulding comprising:
(a) an extruded strip of pliable material having a first surface and an impact-absorbing second surface spanning said first surface;
(b) adhesive means carried by said first surface and adapted to fasten said first surface to a vehicle body;
(c) a decorative strip having two major surfaces and two minor edge surfaces, one major surface being attached to said impact-absorbing second surface, the other major surface having a decorative material thereon, said decorative material being susceptible to weathering at least at the edge surfaces of said decorative strip; and
(d) a transparent weather-resistant coating covering at least the edge surfaces and the portion of said decorative strip immediately adjacent each edge surface thereof and the portion of said extruded strip immediately adjacent said decorative strip.
According to a preferred embodiment of the invention, the decorative moulding comprises;
(a) an extruded strip of pliable material having a first substantially flat surface and an impact-absorbing second surface spanning said first surface;
(b) adhesive means carried by said first surface and adapted to fasten said first surface to a vehicle body;
(c) a decorative strip having two major surfaces and two minor edge surfaces, one major surface being attached to said impact-absorbing second surface of said extruded strip, the other major surface having a decorative material thereon, said decorative material being susceptible to weathering; and
(d) a transparent weather-resistant coating covering said decorative strip and at least the portion of said impactabsorbing second surface immediately adjacent each edge surface of said decorative strip.
Preferably, the weather-resistant coating comprises an acrylic material which covers the decorative strip and the impact-absorbing second surface. For safety and to achieve rapid curing, the weather-resistant coating is formed by applying a liquid which comprises acrylic monomers and then curing the liquid by brief exposure to ultra-violet radiation.
INTRODUCTION TO THE DRAWINGS
For a better understanding of the invention and its advantages, reference may be made to the following detailed description, taken in conjunction with the appended drawings, wherein:
FIG. 1 is an elevational view of a vehicle having the novel decorative moulding applied to the body thereof;
FIG. 2 is a lateral cross-sectional view of a decorative moulding in accordance with one embodiment of the invention;
FIG. 3 is a lateral cross-sectional view of a decorative moulding in accordance with a second embodiment of the invention;
FIG. 4 is a lateral cross-sectional view of a decorative moulding in accordance with a third embodiment of the invention; and
FIG. 5 is a lateral cross-sectional view of a decorative moulding in accordance with a fourth embodiment of the invention.
DETAILED DESCRIPTION
Throughout the figures of the drawings, like reference characters have been used to indicate corresponding parts of the decorative moulding embodiments illustrated therein.
FIG. 1 shows a vehicle A to the body of which a decorative moulding B has been applied as protection against minor impacts causing dents and chipping of paint. Mouldings of this kind are also used on the bodies of trucks, trailers, boats, and other vehicles.
FIG. 2 shows a lateral cross-section of one embodiment of the novel decorative moulding. As shown, the moulding comprises a thick extruded strip 1 of vinyl, polyvinyl chloride, or other material which is sufficiently pliable to conform to the gradually curved surfaces of a vehicle body. Extruded strip 1 has a first surface 1a, which is preferably substantially flat, and an impact-absorbing second surface 1b. Adhesive means, shown as a layer 3 of pressure-sensitive adhesive covered by a strip 3a of protective wax paper or other non-adherent material, is carried by first surface 1a. After stripping away strip 3a, the exposed adhesive layer 3 is used to fasten first surface 1a in the position illustrated for moulding B in FIG. 1.
A decorative strip 2a of thin vinyl, polyvinyl chloride, or other material has two major surfaces and two minor edge surfaces extending the length of decorative strip 2a. The lower, or inner, major surface of decorative strip 2a is attached to the impact-absorbing second surface 1b of extruded strip 1, as by adhesives or by pressure-lamination. The outer major surface of decorative strip 2a has a layer 2b of decorative material thereon which may, for example, be a metallic material such as aluminum. In any event, the decorative material of layer 2b is susceptible to weathering as discussed hereinbefore. To reduce discolouration of layer 2b due to weathering, it is covered with a polyester film 2c. To this point this description of FIG. 2 has been concerned only with prior art features of the moulding cross-section shown therein. In particular, decorative material 2b is uncovered by polyester film 2c, and is therefore susceptible to weathering, at least at the edge surfaces of decorative strip 2a. During prolonged outdoor exposure, the entire layer 2b commonly becomes discoloured and dull because its edges are exposed to weathering.
To overcome this problem a transparent weather-resistant coating 4 is formed to cover the edge surfaces of decorative strip 2a and the portions of decorative strip 2a (or, more specifically, of its protective polyester film 2c) and of surface 1a of extruded strip 1 which are immediately adjacent the aforementioned edge surfaces, Preferably, the coating 4 shown in FIG. 2 is formed by applying a liquid which comprises acrylic monomers and then curing or polymerizing this liquid coating by exposing it to ultraviolet radiation.
It has been found particularly advantageous to use, as the liquid acrylic coating material, the high energy cure coating resin manufactured by Hughson Chemicals Inc. of Erie, Pennsylvania under their product designation RD-3419-60, This liquid acrylic material may be applied by a squeegee roller or the like to the moulding 1 as the latter is extruded (and after decorative strip 2a, layer 2b, and film 2c are bonded to molding 1) at speeds of the order of 90 feet per minute. Moreover, and advantageously, this RD-3419-60 material is a high energy cure coating resin which can be cured very rapidly and with little risk of fire by exposing it briefly to ultraviolet radiation. Thus, the liquid-coated moulding may be conveyed at extrusion speed (e.g. 90 feet/minute) through a chamber irradiated by ultraviolet lamps of preferably high intensity; upon passing through this chamber, the liquid coating will have been cured into a hard acrylic protective coating and the overcoated moulding will be ready for packaging and marketing.
FIGS. 3, 4, and 5 each each show the use of a protective coating 4 on mouldings to which has been applied a decorative strip 2a which has no protective polyester film 2c (as was present in FIG. 2). For this reason, coating 4 covers the entire decorative strip 2a (including its decorative layer 2b) and at least the portion of the impact-absorbing second surface 1b which is immediately adjacent to each edge surface of decorative strip 2a.
FIG. 4 illustrates a moulding provided with a decorative strip along each side of surface 1b, with coating 4 extending for only a short distance beyond decorative strips 2a onto surface 1b. In FIG. 5, coating 4 has been applied over decorative strips 2a and over the entire portion of surface 1b disposed between them.
In acid bath tests, it has been found that prior art mouldings (protected only by polyester film 2c) had their metallic layers 2b disintegrate in several minutes. By contrast, mouldings (as shown in FIGS. 3 and 5) overcoated with only a 0.001 inch thick acrylic coating were found to maintain a bright metallic appearance of their decorative metallic layers 2b for several hours after immersion into the same acid bath. Extrapolation of these results to the much less corrosive atmosphere encountered outdoors by vehicle bodies indicates that the overcoated mouldings of this invention may well maintain a bright appearance for the life of the vehicle to which they are applied.
The invention has been described with reference to the preferred embodiments shown in the drawings. Obvious modifications and changes will suggest themselves to those having ordinary skill, and it is intended that these modifications and changes be encompassed by the invention insofar as they come within the scope of the appended claims. | Decorative extruded vinyl mouldings for protecting auto bodies commonly have a metallized strip of chrome-like appearance laminated to the exposed impact-absorbing surface of the moulding. During prolonged exposure to weathering, the metallized strip becomes dull and unattractive. In this invention, a liquid acrylic coating is applied over the entirety of the metallized strip and cured by utlra-violet radiation at the extrusion speed of the vinyl moulding. | 1 |
CROSS-REFERENCE TO RELATED APPLICATION
This application claims the benefit of U.S. Provisional Application No. 60/260,051, filed Jan. 5, 2001.
SUMMARY OF THE INVENTION
This invention relates to a fence and will have particular but not limited application to a fence formed with substantially extruded plastic materials.
In this invention, the fence includes an upper horizontal rail and a lower horizontal rail with boards extending between the rails. At least one of the rails is formed by separable half parts with each part including a cooperating fastener for securing the parts together about the boards. At least one, and preferably both, of the joined half parts, are formed with protruding ribs which form spacers extending between the boards. A space is formed between adjacent paired ribs of the joined half parts which permits a board to be fitted between the parts and separated from the adjacent board by a protruding rib.
Accordingly, it is an object of this invention to provide a fence which is of simple manufacture and assembly.
Another object of this invention is to provide a fence which can be rapidly and easily assembled and installed.
Still, a further object of this invention is to provide a fence which is of durable and economical construction.
Other objects of this invention become apparent upon the reading of the following description.
BRIEF DESCRIPTION OF THE DRAWINGS
The following described drawings relate to the invention as follows:
FIG. 1 is a perspective view of one embodiment of this invention.
FIG. 2 is a detailed perspective view of that portion of FIG. 1 within circle 2 .
FIG. 3 is a detailed perspective view of that portion of FIG. 1 within circle 3 .
FIG. 4 is a detailed perspective view of that portion of FIG. 1 within circle 4 .
FIG. 5 is a perspective view in fragmentary form of the upper portion of the fence of FIG. 1 with the components thereof separated for purposes of illustration.
FIG. 6 is a fragmentary perspective view of the lower portion of the fence of FIG. 1 .
FIG. 7 is a detailed view similar to FIG. 4 but illustrative of a modified embodiment in which a single half part is utilized as the bottom rail of the fence.
FIG. 8 is a sectional view taken through line 8 — 8 of FIG. 7 .
FIG. 9 is an end view of the rails utilized for the fence of FIG. 1 showing with the half parts thereof in separated form.
FIG. 10 is a perspective view of the separated half parts illustrated in FIG. 9 .
FIG. 11 is a partial elevational view of a fence construction embodying the components of this invention and shown in a modified form.
FIG. 12 is a vertical sectional view of a fence of FIG. 11 .
FIG. 13 is a partial elevational view of another embodiment utilizing the component parts of the invention.
FIG. 14 is a vertical sectional view of a fence of FIG. 13 .
FIG. 15 is partial elevational view of still another embodiment of this invention utilizing the components thereof.
FIG. 16 is a vertical sectional view of the fence of FIG. 15 .
FIG. 17 is an end view of a modified rail construction.
FIG. 18 is an end view of another modified construction of the rail of this invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The preferred embodiments illustrated are not exhaustive or intended to limit the invention to the precise forms disclosed. They are chosen to better describe the invention to enable one skilled in the art to best utilize the invention.
Fence 10 illustrated in FIGS. 1–6 includes a bottom rail 12 , an intermediate rail 14 , and a top rail 16 . Interconnecting rails 12 , 14 and 16 are end posts 18 . Extending between bottom rail 12 and intermediate rail 14 are of boards 20 . In some constructions of this invention, the use of top rail 16 would be eliminated with only rails 12 and 14 being utilized to retain boards 20 . (See FIG. 13 ).
Each of the rails 12 , 14 and 16 are formed into two half parts 22 and 24 . Except for the fasteners 26 which connect the half parts, one half part 22 is essentially a mirror image of the other half part 24 . As best illustrated in FIGS. 5 and 10 , each rail half part 22 and 24 includes an intermediate longitudinal portion which accommodates boards 20 and which is formed with outer edges 28 , 30 , each having a flange 32 spaced inwardly from the upper and lower edges. Overlying flanges 32 are longitudinally spaced ribs 34 which for each rail half part, 22 , 24 protrude inwardly from one of the outer edges 28 , 30 . Ribs 34 forms spacers which separate boards 20 as they extend between the rails. The remaining outer edge 28 , 30 of each rail half part 22 , 24 is formed, preferably, into an uninterrupted flange 36 which parallels the underlying adjacent flange 32 . As will be explained later, in some forms of this construction, flange 36 could also be formed into longitudinally spaced ribs of 34 depending upon the intended construction of the fence. Fasteners 26 form a part of flanges 32 which, when the two half parts are mated or pressed together, form an interfering fit between the half parts, thus forming the rail. The manner and form of fasteners 26 can vary which is shown in FIG. 17 illustrative of a different form of fasteners 26 ′ and in FIG. 18 in which fasteners 26 ′ are illustrated.
With half parts 22 , 24 of each rail 12 , 14 and 16 joined by their respective fasteners 26 , ribs 34 confront one another to form a space 40 between the paired adjacent ribs. This space 40 provides an opening into which a board 20 is fitted with the confronting ribs 34 forming a spacer 41 between the boards. At each end portion of each rail half part 22 , 24 of intermediate rail 14 , flanges 32 and 36 as well as ribs 34 have been removed or notched at 50 to accommodate the end posts 18 . For bottom rail 12 and top rail 16 , flange 36 is not notched at the end portions, although flanges 32 and ribs 34 have been removed at the end portions 51 which not only accommodates the end posts 18 , but allows flanges 36 of half parts 22 , 24 to overlie the top or bottom of the end post 18 as the case may be in an abutting relationship so to provide a covering face at the upper and lower edges of the fence. (See FIGS. 2 and 4 ). The cutout portions 50 , 51 of each rail half part 22 , 24 accommodates end posts 18 when the two half parts are joined and interlocked together by their respective fasteners 26 .
It is best illustrated in FIGS. 2–4 , the end posts are connected to the joined rail half parts 22 , 24 by screw fasteners 44 , which are turned through the half part and into the adjacent end post. The boards 20 which extend between rails 12 and 14 are spaced apart by ribs 34 with the bottom end of the boards resting upon a flange 32 of the adjoining half parts 22 , 24 of bottom rail 12 . FIGS. 7 and 8 depict only a single half part 22 , 24 attached by fastener 44 to the end post 18 .
FIGS. 11 and 12 depict a modified embodiment of this invention in which a lattice work 46 has been inserted between rails 14 and 16 of the fence of the FIG. 1 . This is accomplished by cutting or deleting the ribs 34 , and depending upon the thickness of the lattice work, reducing the middle longitudinal portion of each of the attached half part 22 , 24 of the rails so as to permit the lattice work to be fitted at its upper and lower marginal edges between the connected half parts, as best seen in FIG. 12 . FIGS. 13 and 14 are illustrative of yet another embodiment of this invention in which the top rail 16 and the extended parts of the end posts 18 have been eliminated with only two rails 12 and 14 being utilized to contain the extending boards 20 . FIGS. 15 and 16 are illustrated as still another embodiment of this invention in which extensions 48 of the boards 20 are inserted into rail 14 with its uppermost flanges 36 having been removed to accommodate the post extensions which rest upon the adjacent underlying flange 32 . The posts are held by screw fasteners 49 which extend into the half part 24 of rail 14 and the extensions.
The component parts of this invention are preferably formed from extruded plastic. This provides for an economical, durable, and easily maintained product.
The invention is not to be limited by the details above given, but may be modified within the scope of the appended claims. | A fence which includes upper and lower horizontal rails with boards extending between the rails. The rails are formed into separable half parts which are connectable together about the boards. The half parts include opposing ribs which separate the boards. | 4 |
BACKGROUND OF THE INVENTION
This invention relates to methods of and apparatus for wrapping books and the like. More particularly, the invention relates to wrap-around packing wherein discrete articles are deposited upon carton blanks which are wrapped about the articles to surround all sides of the articles. The thus obtained packages are then ready for stacking, storage or transport
In the art of packaging products of variable length, width and height, it is the practice of the manufacturer to maintain a large inventory of pre-scored and pre-slit containers of varying sizes together with an inventory of filler pads for insertion into the filled containers since normal size variations in so-called standard size products will result in the container selected being slightly too small or too large. Thus, a tight package of the product is not obtained without the use of the aforementioned filler pads.
Moreover, when the production is changed to new sized articles to be wrapped, a different sized pre-scored and pre-slit blank must be inventoried and used. This contributes to the initial cost of the packages and necessitates relatively long interruptions of the packing operation during conversion from the processing of a first dimensioned article to the processing of articles of a different second dimension.
SUMMARY OF THE INVENTION
In accordance with the present invention, articles of different sizes such as different pack sizes of books, are wrapped with a carton formed from a blank in a continuous manner in a new and improved process. This is achieved by taking a standard size blank or blanks and custom trimming the blanks to a size related to the pack size and adjusting the slotting and scoring means to form the blank so that it wraps neatly about the book pack. The preferred process is practiced by an in-line, high speed, case packing machine which can be readily adjusted to handle and carton different sizes of book packs. Preferably information on sizing from previous orders of book packs is stored and used by a controller to reposition slitting knives to cut the blanks to size, to reposition slotting knives to slot the blanks, and/or to reposition scoring blades to score the blanks to neatly fit the carton to the size of the book pack. Thus, the same size of blanks, such as corrugated board blanks, can be customized to the order without having to inventory a large number of blank sizes and/or without having to use filler pads.
This invention provides a machine capable of performing this method in high speed production operation and which will produce a tightly wrapped pack or case that can easily be handled and which is well suited to reduce and to avoid damage to the contents in any such later handling.
In this invention a controller for controlling the sizing, scoring and slotting means has stored information on sizing from previous orders of identical sizes and uses this stored information for automatically adjusting the appropriate scoring blades, trimming knives, etc. in order to produce a pre-sized and pre-formed flat blank which is identical to the said previous orders.
BRIEF DESCRIPTION OF THE DRAWINGS
The drawings show a preferred embodiment of the invention and such embodiment will be described, but it will be understood that various changes may be made from the construction disclosed, and that the drawings and description are not to be construed as defining or limiting the scope of the invention, the claims forming a part of this specification being relied upon for that purpose.
FIG. 1 is a plan view of the system to transport the articles to be packed to the wrapping station and to prepare a properly sized and scored flat blank of wrapping material as shown in FIG. 2;
FIG. 1A shows one possible configuration for the second rotatable cutting wheels of the second cutting and coring station;
FIG. 1B shows one possible configuration for the second rotating scoring wheels of the second cutting and scoring station; and
FIG. 1C shows the third rotating scoring wheel for the second scoring station.
FIG. 2 is a view of a completed pre-scored, trimmed and pre-cut flat blank of wrapping material;
FIG. 3 shows the pre-cut blank wrapping material of FIG. 2 in a first position about material to be wrapped (not shown).
FIG. 4 shows the continued wrapping process with all four sides enclosed.
FIG. 5 shows continued wrapping process with bottom side flaps in final position.
FIG. 6 shows continued wrapping process with top cover in place.
FIG. 7 shows final wrapping with formed lid for opening carton and prior to gluing, labeling and taping.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The carton is formed from a single corrugated sheet or blank 10 , shown in FIG. 2, by the apparatus shown in FIG. 1 .
Flat, corrugated blanks 10 are fed from a stack in a hopper 11 of an up stack sheet feeder 14 by an automatic vacuum blank feed from the top of the stack. The sheet (FIG. 1) is fed by the automatic up stack sheet feeder 14 under the control of a controller 200 in timed relationship onto a conveyor 12 to a first scoring and cutting station 15 . Hopper 11 has the capacity for holding enough blanks 10 for a predetermined period of time, e.g. 10 minutes of operation without refilling. A central controller 200 such as a CPU and/or several programmable controllers controls the timed operation of the sheet feeder 14 and conveyors to deliver the standard size blanks 10 for cutting the blank 10 into the appropriate size for the carton needed to pack a particular pack size of books.
The controller 200 has stored therein the various carton sizes for various book packs. The operator of the apparatus identifies the pack size for the books and the controller has stored in memory the size of carton to be cut from the standard size of blanks and the location of the slits to be made in the blank and location of the scores to be made in the blank. Prior to feeding the first blank into a cutting and scoring station 15 where the blank is cut to size and scored, the cutting knives or knife wheels 25 are first positioned to define lateral sides for the trimmed blank. Herein, the knife wheels 25 may be mounted on oppositely threaded portions of a shaft driven by a precisely positioned stepping motor or the like 205 . The motor is operated by an electrical line 205 a connected to the controller 200 to rotate the shaft 16 and cause the blades to move toward or away from one another relative to a center line through the center of the sheet feeder 14 and the blanks 10 being fed thereby so that equal amounts will be cut from opposite sides of the blank. If desired, each cutting blade 25 could have a separate motor and a separate positioning shaft so that the knives could be moved independently and through respectively different distances.
The controller 200 will in a like manner position scoring wheels 20 mounted on a common shaft 21 having oppositely threaded ends with the shaft 21 being driven by a stepper motor 206 or the like which is connected over and electrical control line 206 a to the controller 200 . Thus, the scoring wheels 20 are adjusted to the positions needed to provide the scoring line locations for the particular carton to be erected for a given pack size of books. The location of the score lines may vary one pack size of books to the next pack size of books.
Prior to feeding the first blank 10 , second edge trimmer knife wheels 65 and second scoring wheels 70 at a second cutting station 55 are positioned by reversible motors in a manner similar to that described above for the knife wheels 25 and scoring wheels 20 .
The location of the cutting and scoring blades in the first station 15 have been predetermined by the programmable controller in the electrical cabinet 200 , and placed in these locations by reversible motors 205 and 206 . The leading edge of a single corrugated sheet 10 is conveyed from the up stacker sheet feeder 12 to the right in the longitudinal direction of the sheet 10 in FIG. 1 through the first scoring and cutting station 15 by a positive feed assembly that either grips and pulls the sheet 10 or pushes the sheet 10 as near as possible to the outside edges. The first scoring wheels 20 will form the first and second score lines 30 and 35 , respectively, as well as the lid flap cuts 45 (FIG. 2) on the corrugated sheet 10 . Rotatable, first edge-trimming knife wheels 25 , are capable of trimming the outside horizontal longitudinally extending edges 40 of the corrugated sheet 10 by up to 3 inches. Scrap trimmed from the longitudinally extending edges 40 will be dropped into and accumulated in a hopper which is at a lower level and which is equipped for rolling out of the machine for dumping by an individual fork lift. The scrap may also be accumulated in a remote area by means of a vacuum system (not shown).
The corrugated sheet 10 is then fed at right angles from the cross feed station 41 to a second cutting station 55 for the short dimension scoring and slitting operations. The location of the cutting and scoring blades 70 and 110 in this station 55 have also been predetermined by a programmable controller in the electrical cabinet 200 , and placed in these locations by reversible motors 207 and 208 . At this second cutting station 55 , rotatable, second edge-trimming knife wheels 65 sever the corrugated sheet 10 at the outside vertical edges 60 to trim the sheet to size. Also, second rotating scoring wheels 70 (FIG. 1 B), will make the third, fourth, and fifth score lines 75 , 80 , and 85 , respectively, while the third rotating scoring wheel 71 (FIG. 1 C), accomplishes the scoring of the sixth score line 90 which includes the scoring of the seventh score lines 115 at first and second top inside end flaps 185 and 190 respectively in the corrugated sheet 10 . Second rotatable cutting wheels 110 (FIG. 1A) sever the sheet to make first and second side-bottom cuts 95 and 100 , respectively, and side-top cut 105 , in the corrugated sheet 10 . The sheet 10 is fed into the wrap-around station 130 to await the arrival of a stack of articles.
Individual articles 120 are fed to the cartoning machine (FIG. 1) by a continuous conveyor 125 , the articles 120 , are then turned and stacked by turner, stacker 127 , delivered by the stack, delivery 128 , and moved on to the transfer, loader 133 , by the infeed, indexing 132 . The transfer, loader 133 , is preferably an air lift transfer table which feeds the stack of individual articles over the top of a scored and cut flat corrugated sheet 10 , in the wrap-around station 130 .
At the wrap-around station 130 , the stacks of individual articles 120 , are seated on the bottom panel 135 , and the stacks and sheet are pushed downward forcing the carton blank through former guides to turn up end and side flaps. A table supports the carton blank and the stack as they move downward. Therefore, as the stacks and carton blank are pushed down, first and second side flaps 160 and 165 (FIG. 3) are bent up about third and fourth score lines 75 and 80 , respectively, to position the first and second side flaps 160 and 165 along the sides of the stack's outer side. Also, first side and second side inside end flaps 150 and 155 (FIG. 4) are plowed to fold along first and second score lines 30 a , 35 a , 30 c , and 35 c ; and first and second bottom end flaps 140 and 145 (FIG. 5) are bent about first and second score lines 30 b , and 35 b to cover the first and second side inside end flaps 150 and 155 . Thus, the stacks of individual articles 120 , are covered on the bottom and the four vertical sides.
Next, the stacks of individual articles 120 , and the corrugated sheet 10 are fed horizontally to a former station where a top panel 170 (FIG. 6) is bent at fifth score line 85 over the top of the stacks of books 120 ; and first and second top outside end flaps 175 and 180 are plowed down about first and second score lines 30 d and 35 d . At the next station, the first and second top inside end flaps 185 and 190 (FIG. 7) are folded at seventh score lines 115 across the first side panel 160 . A top primary flap 195 connected to the top panel 170 at sixth score line 90 is folded down, which is glued to first and second top inside end flaps 185 and 190 to form the lid by which the carton may be opened.
The incoming corrugated sheets 10 and the stacks of individual articles 120 , continuously travel through the cartoning station without stopping. The cartoning machine can accept a stream of 100 books per minute with surges up to 105 BPM and is capable of delivering sealed cartons containing from 8 to 30 books without delaying or causing slowdowns in the incoming product stream. The carton may also be kept compressed, and tape may be wrapped about the carton instead of, or, in addition to, the aforementioned gluing process.
While specific details of a preferred embodiment have been set forth above, it will be apparent that many changes and modifications may be made therein without departing from the spirit of the invention. It will therefore be understood that what has been described herein is intended to be illustrative only and is not intended to limit the scope of the invention. | An apparatus and method for forming a carton from a blank sheet of material, in line, and wrapping it about articles of a predetermined size including cutting and scoring blades which are automatically preset according to parameters previously stored, for these particular articles, in a programmable controller. | 1 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of, and claims the benefit of priority to U.S. patent application Ser. No. 14/789,419 filed on Jul. 1, 2015, which is a continuation of U.S. patent application Ser. No. 14/666,595 filed on Mar. 24, 2015 (and issued as U.S. Pat. No. 9,113,165 on Aug. 18, 2015), which is a continuation of U.S. patent application Ser. No. 14/093,852 filed on Dec. 2, 2013 (and issued as U.S. Pat. No. 9,294,771 on Mar. 22, 2016), which is a continuation of U.S. patent application Ser. No. 14/017,618 filed on Sep. 4, 2013 (and issued as U.S. Pat. No. 8,615,041 on Dec. 24, 2013), which is a continuation of U.S. patent application Ser. No. 13/565,278 filed on Aug. 2, 2012 (and issued as U.S. Pat. No. 8,548,047 on Oct. 1, 2013), which is a continuation of U.S. patent application Ser. No. 13/216,836 filed on Aug. 24, 2011 (and issued as U.S. Pat. No. 8,259,795 on Sep. 4, 2012), which is a continuation of U.S. patent application Ser. No. 11/128,125 filed on May 11, 2005 (and issued as U.S. Pat. No. 8,045,614 on Oct. 25, 2011), which claims the benefit of the filing date of U.S. Provisional Patent Application Ser. No. 60/573,017 filed on May 19, 2004, all of which are hereby incorporated by reference in their entirety.
FIELD OF THE INVENTION
[0002] This invention relates to digital methods for data compressing moving images, and, in particular, to lossy methods that utilize quantization to control the balance between the degree of compression and the fidelity of the compressed result. The invention includes not only methods but also corresponding computer program implementations and apparatus implementations.
BACKGROUND OF THE INVENTION
[0003] A digital representation of still or video images consists of spatial samples of image intensity and/or color quantized to some particular bit depth. This bit depth is typically dependent upon the devices used to capture and display the still or video images. The dominant bit depth for still and video images has been 8 bits. This provides reasonable image quality and each sample fits perfectly into a single byte of digital memory.
[0004] Consequently, almost all image and video compression systems have been limited to 8-bit samples. For example, JPEG is specified only for 8-bit samples of R/G/B and MPEG-2 is specified only for 8-bit samples of Y/U/V. However, 8 bits is certainly not the limit imposed by human vision, and many applications require more fidelity than 8-bit samples can provide. For the case of images captured on film, professional scanners use 10-12 bits in approximately logarithmic units or roughly 14-16 bits linear. Professional video systems routinely require 10-bit data formats. Furthermore, an evolution to bit depths greater than 8 bits is coming to consumers in general. The next version of Microsoft's operating system, code-named Longhorn, is expected to have a new 10-bit per component display interface. In addition, modern compression techniques, such as JPEG2000 and H.264 are more efficient and have fewer artifacts than their predecessors. This makes them capable of compressing higher quality images without artifacts that would negate the benefits of greater bit depths. Also, the ever-increasing bandwidth of wireless and wired networks allows transporting video of larger format and higher quality. Taken together, this means that compression at higher quality levels is efficient enough to be practical. Thus, there is an emerging need for compression systems that operate with samples whose bit depth is greater than 8 bits.
[0005] Such greater bit depths allow higher fidelity in the overall compression. The fidelity of a compressed image is measured by the distortion, which is the mean-squared error (MSE) between the original image or frame and the reconstructed (compressed) image or frame normalized to the maximum possible (peak) amplitude and measured in logarithmic units. In short, the distortion PSNR (Peak Signal-to-Noise Ratio) in dB is
[0000] PSNR=10 log(peak 2 /MSE) (1)
[0000] Greater bit depths permit higher values for PSNR. For example, the quantization error for N-bit sampling is commonly modeled as independent, uniformly distributed random noise over the interval [−½, ½] so that the MSE is 1/12 with respect to the least significant bit. Since the input samples are integers in the range [0, 2 N −1], the peak value is 2 N −1. The PSNR corresponding to this MSE is
[0000] PSNR=10 log((2 N −1) 2 /( 1/12)) (2)
[0000] Since this represents the error between the original, unquantized image and its quantized representation, it represents an upper bound for the fidelity of the compressed result compared to the original image. Table 1 shows this upper bound for some representative bit depths:
[0000]
TABLE 1
Maximum PSNR as a function of bit depth
PSNR limit (dB)
bit depth (bits)
(due to round-off)
8
58.92
10
70.99
12
83.04
14
95.08
16
107.12
[0006] All lossy compression systems, such as the example schematically shown in FIG. 1 , incur some form of a trade-off between the degree of compression (the number of compressed bits in the case of a still image and the bit rate in the case of moving images) and the fidelity. This performance is formally characterized by a “rate-distortion” (R-D) curve. This curve is a graph of the distortion (in PSNR) as a function of the bits or bit rate required for the compressed representation (typically in Kbytes for images and Mbits/sec for moving images or video). FIG. 5 shows an example of a typical R-D curve. Rate-distortion curves show how well a particular compression-decompression system, or “codec,” performs over a range of compression ratios or bit rates for a particular input image or video sequence.
[0007] FIG. 1 shows schematically a generic prior art image compression/decompression system in which an original image is applied to an Encoder 2 . The encoder's compressed bits output are applied to a Decoder 4 that produces a decompressed version of the image. The original image is compared to the decompressed image in a PSNR calculation 6 to provide the PSNR.
[0008] The method used to control where along the rate-distortion curve a compression system operates is through the use of a quantization parameter, or QP, to control quantization as indicated in FIGS. 4 and 5 , which figures are described further below. The parameter QP determines the quantization step-size, QS, which is then directly used in quantization and dequantization functions or devices. The most general interpretation is that an integer QP is used to index a table of values for QS. Such a table contains a mapping from QP to QS. Thus, in FIG. 4 , which shows schematically a generic prior art quantization and dequantization system, the quantization parameter QP is applied to a first mapping function 10 that generates a corresponding quantization step-size QS in accordance with predetermined mapping relationships. The same QP value is also applied to a second mapping function 12 that generates the same corresponding quantization step-size QS in accordance with the same predetermined mapping relationships. The quantization step-size QS produced by mapping function 10 controls the step size of quantizer 14 that receives an N-bit data word X. Quantizer 14 produces a quantized data word Q having a bit length that is a function of N, the quantization parameter QP, and the quantization step-size QS. Dequantizer 16 receives the quantized data word Q along with QS and produces a dequantized N-bit data word X′ that approximates the input N-bit data word X.
[0009] FIG. 5 , shows a rate-distortion curve (distortion PSNR versus bit rate as QP is varied) for a hypothetical codec that employs both an identity mapping (QP=QS), such as that employed in prior art MPEG-1, MPEG-2 and MPEG-4 systems, and an exponential mapping, such as that employed in the H.264 system (QS=2 QP/6-L ). The distribution of quantization parameters QP is shown along the curve. The QP values above the curve are those for the identity mapping and the QP values below the curve are those for the exponential mapping. For identity mapping, low values of QP (indicating higher quality coding) are relatively sparse, becoming denser for high values of QP (lower quality coding). For exponential mapping, more values of QP are available for low values of QP and the distribution of QP values is more uniform than for the identity mapping.
[0010] FIG. 2 and FIG. 3 show block diagrams for an H.264 encoder and decoder, respectively. H.264, also known as MPEG-4/AVC, is considered the state-of-the-art in modern video coding. Although H.264 possesses many of the features common to previous MPEG (ISO) and ITU video codecs, it has many innovations. Although aspects of the present invention are usable in MPEG-1, MPEG-2 and MPEG-4 coding environments, aspects of the present invention may be used with particular advantage in H.264 coding environments. Details of H.264 coding are set forth in “Draft ITU-T Recommendation and Final Draft International Standard of Joint Video Specification (ITU-T Rec. H.264 | ISO/IEC 14496-10 AVC),” Joint Video Team (JVT) of ISO/IEC MPEG & ITU-T VCEG (ISO/IEC JTC1/SC29/WG11 and ITU-T SG16 Q.6), 8 th Meeting: Geneva, Switzerland, 23-27 May 2003. Details of the “Fidelity Range Extensions” to the basic H.264 specifications are set forth in “Draft Text of H.264/AVC Fidelity Range Extensions Amendment,” Joint Video Team (JVT) of ISO/IEC MPEG & ITU-T VCEG (ISO/IEC JTC1/SC29/WG11 and ITU-T SG16 Q.6), 11 th Meeting: Munich, Del., 15-19 Mar. 2004. Both of the just-identified documents are hereby incorporated by reference in their entireties. The “Fidelity Range Extensions” will support higher-fidelity video coding by supporting increased sample accuracy, including 10-bit and 12-bit coding. Aspects of the present invention are particularly useful in connection with the implementation of such increased sample accuracy. Further details regarding the H.264 standard and its implementation may be found in various published literature, including, for example, “The emerging H.264/AVC standard,” by Ralf Schafer et al, EBU Technical Review, January 2003 (12 pages) and “H.264/MPEG-4 Part 10 White Paper: Overview of H.264,” by kin E G Richardson, Jul. 10, 2002, published at www.vcodex.com. Said Schafer et al and Richardson publications are also incorporated by reference herein in their entirety.
[0011] The H.264 encoder shown in FIG. 2 has elements now common in video coders: transform and quantization methods, entropy (lossless) coding, motion estimation (ME) and motion compensation (MC), and a buffer to store reconstructed frames. H.264 differs from previous codecs in a number of ways: an in-loop deblocking filter, many modes for intra-prediction, a new integer transform, two modes of entropy coding (variable length codes, and arithmetic coding), motion block sizes down to 4×4 pels, and so on. Of particular importance here is that H.264 has a different distribution of quantization step-sizes that makes its extension to higher bit depths more efficient than MPEG-2, for example. The outlined portion of FIG. 2 relates to the description of FIG. 7 a , below.
[0012] The H.264 decoder shown in FIG. 3 can be readily seen as a subset of the encoder. The new quantization methods forming aspects of the present invention apply to both the decoder and the encoder. The outlined portion of FIG. 3 relates to the description of FIG. 7 b , below.
[0013] All lossy image and video compression systems, including H.264 and all the other JPEG/MPEG/ITU standards, use quantization as the primary means to control the degree of compression, and hence the fidelity of the result. In other words, the degree of quantization used determines the operating point along the rate-distortion curve. This may be seen, for example, in FIG. 5 .
[0014] The most common form of quantization is uniform (linear) quantization. MPEG-2 employs uniform quantization. In uniform quantization the quantized value is the original value scaled by a quantization step size (whose inverse is called the quantization resolution), QS, and converted to an integer
[0000] Q=int[X /QS+ r] (3)
[0000] where X is the continuous variable to be quantized, Q is the quantized value, and r is an optional rounding parameter in the interval [0,1). If r is 0, the quotient is truncated. If r is ½, the result corresponds to simple rounding. Other values of r are possible and useful. The corresponding dequantized value is
[0000] X′=Q ×QS+ s (4)
[0000] where s is another rounding parameter, so that X′ is the quantized approximation to X. As described above, FIG. 4 shows this prior art in quantization and dequantization. Note that the number of bits used for the input, X, and the number of bits for the output, X′, are the same and there is a single quantization step-size, QS.
[0015] As discussed above, the method used to control where along the rate-distortion curve a compression system operates is through the use of a quantization parameter, or QP, to control quantization as indicated in FIGS. 4 and 5 . The parameter QP determines the quantization step-size, QS, which is then directly used in the quantization and dequantization equations 3 and 4 (above). The most general interpretation is that an integer QP is used to index a table of values for QS. This table contains the mapping from QP to QS. There are two common mappings from QP to QS: an identity mapping (used in MPEG-2 and other standards)
[0000] QS=QP (5)
[0000] and an exponential mapping
[0000] QS=2 QP/6-L (6)
[0000] which is used in H.264 (the value of L differs for quantizing luma versus chroma in this standard). Note that the quantization step-size is an integer for the identity mapping, while for the exponential mapping it is a floating-point number approximated by an integer. More precisely, in H.264, QS is represented by one of six integers, {2 M , 2 M+1/6 , . . . , 2 M+5/6 }, for some value of M plus a number of shifts necessary to account for the difference between M and the integer portion of (QP/6) and L.
[0016] The identity and exponential mappings distribute quantization step-sizes very differently. The identity mapping is sparse for low QP values, but dense for high QP values, as indicated in FIG. 5 . In contrast, the density of QP values for H.264 is more uniform. Table 2 compares these two mappings for each factor of two (octave) in quantization step-size. “QS#” is the number of quantization step sizes in the octave. This information may also be seen in FIG. 5 . As shown in the table and in the figure, QP values of 1, 2, 4, 8, 16 and 32 for identity mapping correspond, respectively, to QP values of 0, 6, 12, 18, 24 and 30 for exponential mapping.
[0000]
TABLE 2
Distribution of quantization step-sizes
Identity Mapping
Exponential Mapping
Octave
QS# {QP values}
QS# {QP values}
1
1
{1}
6
{0-5}
2
2
{2-3}
6
{6-11}
3
4
{4-7}
6
{12-17}
4
8
{8-15}
6
{18-23}
5
16
{16-31}
6
{ 24-29}
6
1
{32}
6
{30-35}
7
—
6
{36-41}
8
—
6
{42-47}
9
—
5
{48-52}
[0017] The exponential mapping has the same density of quantization step-sizes for each octave. FIG. 5 shows how these two compare for a hypothetical rate-distortion plot (“hypothetical” in the sense that no existing codec is known to use both mappings). As mentioned above, the identity mapping is relatively sparse for low QPs, and very dense for high QPs, while the exponential mapping is relatively uniform for all QPs. As discussed further below, this makes the extension of quantization to higher bit depth much more efficient for H.264 with its exponential mapping than with the identity mapping of MPEG-2.
[0018] The prior art does nothing to normalize the effects of varying bit depth when performing quantization and dequantization operations. That is, the prior art simply uses equation (3) with equations (5) or (6) for quantization, and equation (4) for dequantization, without any modification for bit depth. This was the approach taken in the MPEG-4 N-Bit and Studio video compression profiles, which were designed to encode bit depths of up to 12 bits. However, because no changes were made to the quantization and dequantization methods when bit depth changes, the same value for QP produces different values for PSNR at different bit depths. What causes this is discussed below in connection with prior art quantization methods (and Table 3). At this point, the effects are set forth.
[0019] Suppose that for the MPEG-2 N-Bit profile a particular value of QP results in a PSNR of 40 dB at an 8-bit encoding depth; at a 10-bit encoding depth the same QP will result in a PSNR of roughly 52 dB. This change in PSNR reflects underlying differences in the coded bitstream—the number of bits in each quantized word in the bitstream is greater in the case of the 10-bit encoding depth. In order to have the same PSNR and the same quantized word lengths in the bitstream, the 10-bit QP would have to be four times as large. These differences make it more difficult to design encoders and decoders that can handle different bit depths, even though the 8-bit compression at QP and the 10-bit compression at 4 times that QP produce nearly identical compressed data—the quantized word lengths are the same but the underlying data represented by them may differ by a rounding difference. Thus, for a given QP value, the syntax and semantics of the bitstream produced by current encoders is not compatible for different bit depths. It would be advantageous to standardize QP parameters and quantized values among different bit depths. For the prior art, a compressed bitstream generated from 10-bit data using a 10-bit encoder will not play on current 8-bit decoders because QP and all the quantized values mean different things at different bit depths.
SUMMARY OF THE INVENTION
[0020] In a first aspect, the invention provides a method for digital encoding and decoding, comprising (1) processing digital symbols representing a moving image, each symbol S having a bit depth N, to provide intermediate variables X, each having a bit depth N+K, where K is a function of the processing, (2) quantizing each intermediate variable X with a quantizing step size QS N to produce a quantized data word Q, wherein QS N is a function of a quantization parameter QP, which function has been normalized to the most significant bit of the N-bit bit depth, (3) processing, including entropy coding, the quantized data words Q to provide an encoded bitstream, (4) processing, including entropy decoding, the encoded bitstream, to provide quantized data words Q, (5) dequantizing each quantized data word Q with a dequantization step size QSM to produce a dequantized intermediate (M+K)-bit variable X′ that approximates the intermediate (N+K)-bit variable X, wherein QSM is the same function of the quantization parameter QP as is QS N but has been normalized to the most significant bit of an M-bit bit depth, and (6) processing the intermediate variables X′ to produce digital symbols, each symbol S′ having a bit depth M, representing an approximation of the moving image.
[0021] In another aspect, the invention provides for a method for producing an encoded bitstream in response to digital symbols representing a moving image, comprising (1) processing the digital symbols, each symbol S having a bit depth N, to provide intermediate variables X, each having a bit depth N+K, where K is a function of the processing, (2) quantizing each intermediate variable X with a quantizing step size QS N to produce a quantized data word Q, wherein QS N is a function of a quantization parameter QP, which function has been normalized to the most significant bit of the N-bit bit depth, and (3) processing, including entropy coding, the quantized data words Q to provide an encoded bitstream having the same syntax and semantics for a given quantization parameter QP regardless of the bit depth N.
[0022] In a further aspect, the invention provides for another method for producing an encoded bitstream in response to digital symbols representing a moving image, comprising (1) processing the digital symbols, each symbol S having a bit depth N, to provide intermediate variables X, each having a bit depth N+K, where K is a function of the processing, (2) quantizing each intermediate variable X with a quantizing step size QS N to produce a quantized data word Q, wherein QS N is a function of a quantization parameter QP, which function has been normalized to the most significant bit of the N-bit bit depth, and (3) processing, including entropy coding, the quantized data words Q to provide an encoded bitstream wherein the portions of the bitstream representing the quantized data words Q are substantially identical for a given quantization parameter QP regardless of the bit depth N, differing by rounding errors between respective ones of the intermediate variables X and the quantized data words Q for different bit depths N.
[0023] In yet another aspect, the invention provides for a method for digital encoding, comprising processing digital symbols representing a moving image, each symbol S having a bit depth N, to provide intermediate variables X, each having a bit depth N+K, where K is a function of the processing, and quantizing each intermediate variable X with a quantizing step size QS N to produce a quantized data word Q, wherein QS N is a function of a quantization parameter QP, which function has been normalized to the most significant bit of the N-bit bit depth.
[0024] In yet a further aspect, the invention provides for a method for digital encoding and decoding, comprising (1) processing digital symbols representing a moving image, each symbol S having a bit depth Nc, where Nc is a function of the color component c, where c represents one of the color components RGB or YUV or equivalent, to provide intermediate variables Xc, each having a bit depth Nc+K, where K is a function of the processing, (2) quantizing each intermediate variable Xc with a quantizing step size QS Nc to produce a quantized data word Qc, wherein QS Nc is a function of a quantization parameter QP, which function has been normalized to the most significant bit of the Nc-bit bit depth, (3) processing, including entropy coding, the quantized data words Qc to provide an encoded bitstream, (4) processing, including entropy decoding, the encoded bitstream, to provide quantized data words Qc, (5) dequantizing each quantized data word Qc with a dequantization step size QS Mc to produce a dequantized intermediate (Mc+K)-bit variable Xc′ that approximates the intermediate (Nc+K)-bit variable Xc, where Mc is also a function of the color component c, wherein QS Mc is the same function of the quantization parameter QP as is QS Nc but has been normalized to the most significant bit of an Mc-bit bit depth, and (6) processing the intermediate variables Xc′ to produce digital symbols, each symbol S′ having a bit depth Mc, representing an approximation of the moving image.
[0025] In still another aspect, the invention provides for a method for decoding a bitstream wherein the bitstream was generated by processing digital symbols representing a moving image, each symbol S having a bit depth N, to provide intermediate variables X, each having a bit depth N+K, where K is a function of the processing; quantizing each intermediate variable X with a quantizing step size QS N to produce a quantized data word Q, wherein QS N is a function of a quantization parameter QP, which function has been normalized to the most significant bit of the N-bit bit depth; and processing, including entropy coding, the quantized data words Q to provide an encoded bitstream, comprising (1) processing, including entropy decoding, the encoded bitstream, to provide quantized data words Q, (2) dequantizing each quantized data word Q with a dequantization step size QSM to produce a dequantized intermediate (M+K)-bit variable X′ that approximates the intermediate (N+K)-bit variable X, wherein QSM is the same function of the quantization parameter QP as is QS N but has been normalized to the most significant bit of an M-bit bit depth, and (3) processing the intermediate variables X′ to produce digital symbols, each symbol S′ having a bit depth M, representing an approximation of the moving image.
[0026] Other aspects of the invention include apparatus adapted to perform the methods of any one of the aspects of the invention just described and computer programs, stored on a computer-readable medium for causing a computer to perform the methods of any one of the aspects of the invention just described.
[0027] Aspects of the present invention provide for uniform bitstream syntax and semantics, independent of the bit depth.
[0028] Another aspect of the present invention is that the effect of a given QP should be essentially independent of bit depth. In other words, a particular QP value should have a standard effect on image quality, regardless of bit depth. This may be referred to as “QP invariance” and it may be achieved by normalizing the quantization step-size QS to the most significant bit of the bit depth of the variable being quantized. By doing nothing different as bit depth changes, previous image processing methods normalize the quantization step-size to the least significant bit of the bit depth of the variable being quantized.
[0029] Once the effects of QP are standardized with respect to the bit depths of the input samples, it is easier to allow the bit depth of individual color components to be different from each other. Formats with different bit depths for different color components are quite common, often a result of the sensitivity of human vision to different colors. For example, the 5/6/5 RGB format uses 5 bits for Red, 6 bits for Green, and 5 bits for Blue, which fits exactly into a 16-bit word and represents the important green color with higher fidelity. If one attempts to use such color formats with existing compression systems, it would compress the different color components with vastly differing fidelity. This could be remedied by adding separate QP parameters for each component, for example QP R , QP G , QP B . However, current standards for video compression do not allow this. This invention facilitates the native compression and decompression for these color formats that have unequal bit depths. Formats with unequal bit depths can also arise from color space transformations. Malvar and Sullivan have described a lifting-based transformation between RGB at N/N/N bits and YCoCg at N/N+1/N+1 bits, which is exactly invertible using integer arithmetic. H. Malvar and G. Sullivan, “YCoCg-R: A Color Space with RGB Reversibility and Low Dynamic Range,”,” ISO/IEC JTC1/SC29/WG11 and ITU-T SG16 Q.6 document JVT-I014r3, July 2003. Thus, the ability to code YCoCg at unequal bit depths allows the indirect coding of N-bit RGB data without any fidelity loss from the color space transformation. Thus, it is a further aspect of the invention to allow different bit depths for different components of a video signal and to compress each with the same fidelity (i.e., the same QP).
[0030] It is a further aspect of the present invention to produce a single compressed representation for any given value of QP that can be decoded, at least approximately (e.g., subject to round off errors), at any desired bit depth. With this invention, it no longer necessary to have different bitstreams that are incompatible because of bit depth. By standardizing the effects of QP, two decoders at different bit depths perform the identical calculations but with differing precision. Without this standardization, decoders require determining the meaning of QP with respect to the bit depth of the encoder versus the bit depth of the decoder.
[0031] Another aspect of the invention is that one may encode the image or video input at its native (original) bit depth and decoding may take place at whatever bit depth is desired or possible. While this may result in small drift between an N-bit decoding and an M-bit decoding if the decoded bit depth is greater than the encoded bit depth, such drift may not be noticeable for common coding situations.
[0032] The invention is designed so that the rate-distortion performance of a compression system is independent of the bit depth of the data that is encoded. Therefore, the rate-distortion performance at a given QP should be the same (within the limits of round-off error) regardless of bit depth. This is achieved by normalizing the quantization step-size, QS, to the most significant bit of the data to be encoded. Thus the quantization step-size, QS, is a function of both the quantization parameter, QP, and the number of bits used in data being encoded as shown in FIG. 6 .
DESCRIPTION OF THE DRAWINGS
[0033] FIG. 1 shows schematically a generic prior art image compression/decompression system.
[0034] FIG. 2 shows a block diagram for an H.264 encoder.
[0035] FIG. 3 shows a block diagram for an H.264 decoder.
[0036] FIG. 4 shows prior art in quantization and dequantization.
[0037] FIG. 5 shows a rate-distortion curve.
[0038] FIG. 6 shows schematically a generic quantization and dequantization system in accordance with aspects of the present invention.
[0039] FIGS. 7( a ) and 7( b ) show schematically a generic depiction of a video encoder and decoder, respectively, showing how quantization and dequantization aspects of the present invention may be employed in such encoders and decoders.
[0040] FIG. 8 shows schematically how higher bit depths add more negative values for QP.
[0041] FIG. 9 shows a rate-distortion curve.
DETAILED DESCRIPTION OF THE INVENTION
[0042] In a preferred embodiment, a quantization parameter, QP, determines the quantization step-size, QS. In order to achieve QP invariance as bit depth changes, it is necessary to normalize QS with respect to the most significant bit of the input data sample bit depth. If a given QP maps to a quantization step-size QS 8 for 8-bit samples, then the resulting quantization step-size for N-bit samples is
[0000] QS N =QS 8 ×2 N-8 (7)
[0000] so that the basic quantization equation for N-bit samples
[0000] Q=int[X /QS N +r] (8)
[0000] becomes
[0000] Q=int[X× 2 8-N /QS 8 +r] (9)
[0000] Then dequantization for M-bit samples
[0000] X′=Q ×QS N +s (10)
[0000] becomes
[0000] X′= 2 M−8 ×Q ×QS 8 +s (11)
[0000] Note that the implementation of these changes simply requires additional shift operations with respect to the operations on 8-bit data. Although equations 7 through 11 may be expressed more generally, they are expressed with respect to an 8-bit reference because 8-bit bit depths have been common heretofore.
[0043] FIG. 6 shows schematically a generic quantization and dequantization system in accordance with aspects of the present invention. The quantization parameter QP is applied to a first mapping function 22 that generates a quantization step-size QS N in accordance with predetermined QP to QS mapping relationships and a bit depth N. The quantization step-size QS N is determined in accordance with equation 7 (above). N+K is the bit depth of the (N+K)-bit data words X applied to quantizer 24 that quantizes the X data words in accordance with step-size QS N to produce quantized data words Q having a bit length that is a function of QP, as discussed further below The same QP value is also applied to a second mapping function 26 that generates a quantization step-size QSM in accordance with the same predetermined QP to QS mapping relationships but in response to a bit depth M that may be different from the bit depth N to which mapping 22 is responsive. Bit depth M+K is the bit depth of the (M+K)-bit data words produced by dequantizer 28 . The dequantization step size QSM is determined in accordance with equation 7 (above). Dequantizer 28 receives the quantized data words Q and produces (M+K)-bit data words X′ that approximate the X data words.
[0044] FIG. 7 shows schematically a generic depiction of a video encoder and decoder, such as the H.264 encoder and decoder shown in FIG. 2 and FIG. 3 , showing how quantization and dequantization aspects of the present invention may be employed in such encoders and decoders. For the encoder of FIG. 7( a ) , the block labeled “Process (Transformation)” transforms the input samples into the variables to be quantized. This block corresponds generally to the portion of FIG. 2 enclosed by the dashed lines. The block labeled “Process (Entropy coding)” assembles an encoded bitstream after entropy coding the quantized variables. Similarly, for the decoder in FIG. 7( b ) , the block labeled “Process (Entropy decoding)” parses encoded bitstream and entropy decodes the entropy-coded quantized variables. The block labeled “Process (Reconstruction)” reconstructs the output samples from the decoded and dequantized variables and corresponds generally to the portion of FIG. 3 enclosed by the dashed line.
[0045] The encoder shown in FIG. 7( a ) receives input symbols S of N bits and transforms them into a sequence of variables X having N+K bits where K is a function of the “Process (Transformation)” block and is typically greater than zero. The encoder is also provided with a QP value and the bit depth N of the input symbols S. Each variable X is quantized by a quantizing step-size QS N appropriate for a sample bit depth of N. QSN is determined by a mapping from QP to QS 8 followed by the normalization given by equation 7. The resulting quantized variables are entropy coded and combined with N, QP and other parameters to produce an encoded bitstream. In practice, QP needs to be sent in the bitstream only when it changes. Sending N is useful for indicating that drift reduction is required if M<N or that emulation of lower precision arithmetic in the decoder is required if M>N. N is required to indicate the number of additional values of QP may be required. The encoded bitstream is decoded by the decoder shown in FIG. 7( b ) to yield the original N, QP, additional parameters and the quantized variables Q. In the decoder, these quantized variables are dequantized with a quantization step-size QSM appropriate for M bit samples of the desired output. QSM is derived analogously to QS N using a mapping from QP to QS 8 followed by the normalization to M bits given by equation 7. The final output S′ is thus an M-bit approximation to the N-bit samples S in the original image.
[0046] Fully utilizing the capabilities of greater bit depths requires smaller values for the quantization step-size, QS. To achieve the improved quality (the higher PSNR shown in Table 1) possible with greater bit depths while maintaining QP invariance requires not only the retention of existing values for QS but also requires additional values for QP to indicate the newly added finer values for QS. Retaining the existing values of QS may also require newly added intermediate values of QP, as is explained further below.
[0047] The prior art, by normalizing the quantization with respect to the least significant bit, adds finer quantization step-sizes at the expense of losing coarser values of QS as shown in Table 3. The example of Table 3 pertains to identity mapping in which QP=QS. While the quantization step-sizes are the same with respect to the LSB for 8-bit and 10-bit bit depths (QS 8 and QS 10 are the same value as QP for both bit depths in the case of LSB normalization), they are not with respect to the MSB (for example, 2 −8 for QS 8 and 2 −10 for QS 10 for QP=1 in the case of MSB normalization). Thus the quantization step-sizes for 10 bits have additional fine values for QP=1,2,3, but sacrifice all the quantization step-sizes larger than 2 −5 with respect to the MSB.
[0000]
TABLE 3
Prior art quantization for identity mapping
QS 8
QS 10
QP
LSB (MSB)
LSB (MSB)
1
1 (2 −8 )
1 (2 −10 )
2
2 (2 −7 )
2 (2 −9 )
3
3
3
4
4 (2 −6 )
4 (2 −8 )
. . .
. . .
. . .
8
8 (2 −5 )
8 (2 −7 )
. . .
. . .
. . .
16
16 (2 −4 )
16 (2 −6 )
. . .
. . .
. . .
32
32 (2 −3 )
32 (2 −5 )
[0048] For this invention, the manner in which these new quantization step sizes are added depends on the mapping from QP to QS introduced previously in equations (5) and (6).
[0049] In the case of the identity mapping
[0000] QS=QP (12)
[0000] used in MPEG-2 and elsewhere this means that QP should now indicate additional values for QS in order to exploit more fully the benefits of greater bit depths. For example, suppose that for 8-bit bit-depth, input samples the values for QP are the integers {1, 2, 3, 4 . . . K} and therefore the values for QS are simply the same integers {1, 2, 3, 4 . . . K}. The quantization step-sizes for 10 bits that achieve QP invariance (for the original values of QP) are then the intermediate QS values {4, 8, 12, 16 . . . 4×K}. This skips over the integers up to and between those values, i.e., {1, 2, 3, 5, 6, 7, 9, 10, 11 . . . 4×K−2, 4×K−1}. Thus, to have all the possible integer quantization step-sizes at 10-bits (i.e., all of the original step sizes and all of the new finer step sizes), QP requires two extra “fractional” bits to indicate the values {¼, ½, ¾, 1, 1¼, 1½, 1¾, 2, . . . , K−¼, K}. An example of such a relationship between QP and QS at bit depths of 8 and 10 that achieves QP invariance is shown in Table 4.
[0000]
TABLE 4
QP, and QS at 8 and 10 bits for identity
mapping to achieve QP invariance
QP
QS 8
QS 10
¼
¼
1
½
½
2
¾
¾
3
1
1
4
1 ¼
1 ¼
5
. . .
. . .
. . .
K-¼
K-¼
4 × K-1
K
K
4 × K
[0050] The case of identity mapping requires determining the number of fractional and integer bits in QP. One way to achieve this is to send the input bit depth, N, in the compressed bitstream. The number of fractional bits in QP (and hence QS) is simply N−8.
[0051] The following two examples illustrate the quantization method according to aspects of the present invention for the case of identity mapping. Table 5 compares the coding of 10-bit data and the same data rounded to 8-bits at QP=1 to show that the results agree as one would expect. In practice, one would not have to make a separate encoding at 8 bits, instead, one could encode at 10 bits and then decode at 8 or 10 bits. For a given value of QP, the quantization step-size, QS, changes with bit depth according to Equation (7). X is the data to be quantized, which, in this example, has two more bits than the input data, i.e., K=2. Thus, what is referred to herein as the “8-bit X” has 10 (=N+K) bits. The 8-bit X is the 10-bit X rounded to 8 bits. Note that the quantized values Q are exactly the same because they are a function of QP (in this example, a QP of 1 results in a quantized bit length of 10 bits regardless of the bit depth). It is the equality, within rounding error, of the quantized values Q that unifies operation for a given value of QP at different bit depths, allowing the bitstreams for different bit depths to be compatible for a given value of QP. Note that the dequantized values X′ are the same to within the rounding error (interpreting the 2 least significant bits of the 10-bit version as fractional bits when comparing to the 8-bit version). Thus, substantially the same quality results at different bit depths when QP has the same value at the different bit depths.
[0000]
TABLE 5
Comparing 8 and 10 bit encoding and decoding
8-bit encoding
10-bit encoding
Variable
and decoding
and decoding
QP
1
1
QS
1
4
X
0001110101
000111010011
Q
0001110101
0001110101 (assuming r = ½)
X′
0001110101
000111010100
[0052] Table 5 example shows that the quantized values, Q, always have the same scale regardless of bit depth for a given QP. This makes 8-bit and 10-bit compressed bitstreams nearly identical in content, differing only to the extent of any rounding error. The respective bitstreams resulting from the same QP value thus may be identical in syntax and semantics even though they represent different encoded bit depths.
[0053] The second example, in Table 6, compares 8- and 10-bit decoding at a QP of ¼, assuming an enhanced 8-bit decoder that can accept fractional QPs. In this case X′ differs by rounding error as one would expect.
[0000] TABLE 6 Comparing 8 and 10 bit decoding 10-bit encoding and Variable 8-bit decoding decoding QP ¼ ¼ QS ¼ 1 X . . . 000111010011 Q 000111010011 000111010011 X′ 0001110101 (assuming s = ½) 000111010011
Overall, the differences in dequantized values X′ are within rounding error (Table 1). As in the Table 5 example, the number of bits required for the quantized values, Q, is a function of QP, but not bit depth. Such results are due to the scaling for QS given in Equation 7 and are true independent of the mapping from QP to QS. In the Table 6 example, QP has a lower value, resulting in the potential of a higher quality decoded X′ (Q is 10 bits rather than 8 bits as in the Table 5 example, allowing a 10-bit decoding (or, if desired, an 8-bit decoding with a loss of resolution). For the case of 8-bit decoding, it is assumed that the encoder receives an input X having a bit depth of 10 bits (or more) in order to obtain a 10-bit quantized value Q in which the last two least significant bits are not zero.
[0054] For the case of the exponential mapping used in H.264,
[0000] QS=2 QP/6-L (13)
[0000] making it necessary only to extend the range of QP in the negative direction. The values for QP remain integers although they are now signed. Because of the QP/6 in the exponent, every additional bit of sample bit depth allows the minimum value for QP to decrease by 6. Thus if the QP range for 8 bits is, say, [0, 51] then the QP range for 10 bits would be [−12, 51]. In addition to QP remaining an integer, this mapping allocates QP values more efficiently than the identity mapping as was described earlier and shown in Table 2 and FIG. 5 . Higher bit depths enable higher quality, which occurs at lower values of QP. The exponential mapping adds all these additional QP values in this range. FIG. 8 shows schematically how higher bit depths add more negative values for QP. We can now see why the exponential mapping provides a more efficient framework in which to add these new QP values. In going from 8 to 10 bits, the identity mapping requires two extra bits to represent QP but only adds three values, {¼, ½, ¾}, of smaller quantization step-sizes, with the other additional values filling in between existing QP values, most of which are at high QP (low quality) values. In contrast, with the exponential mapping each additional bit of sample depth adds six smaller QP (and QS) values. Thus, going from 8 to 10 bits adds 12 finer QS values for the exponential mapping while the identity mapping adds only 3. Furthermore, it requires fewer bits to signal these additional QP values. Using just one extra bit (the sign bit) in the representation of QP is sufficient to handle a bit depth of 16 bits.
[0055] These changes enable the possibility of compatible compressed bitstreams. Once the effects of bit depth are properly accounted for, the compressed representation is essentially independent of bit depth. That is, all control elements of the stream (such as QP) are exactly the same. Numerical elements (such as quantized values, like Q) are the same to within round-off error. Informational elements (such as the bit depth, N) can differ. Consequently, decoders of differing bit depths simply use more or less precision in their calculations. Examples of decoding at bit depths greater than encoded bit depths are give in United States Patent Publication US 2002/0154693 A1, of Gary A. Demos et al, published Oct. 24, 2002. Said Demos et al application is hereby incorporated by reference in its entirety.
[0056] The rate-distortion curve in FIG. 9 illustrates a fundamental principle—that QP determines the overall system performance within the constraints of the encoding and decoding bit depths. That is, QP, which represents the quantization of the compressed data is the dominant controller of quality, while the bit depth, which represents the quantization of the input and output samples, only determines whether or not the best performance possible for a given QP is achieved. The operating point indicated by “X” is at one QP and the two indicated by “Y” are at a different and smaller QP. The QP indicated by X yields essentially the same performance regardless of bit depth. Conversely, the performance at the QP indicated by Y is a case where the QP is so low that 10 bits are required to achieve the best possible PSNR.
[0057] Thus, it becomes possible, for example, to encode data at its original or native (i.e., highest) bit depth, and then decode at any desired bit depth. In this way, the original bit depth limits the quality of the decompressed result, the decompressed bit depth, and the compressed bit rate in an optimal way.
[0058] FIG. 9 shows the resulting behavior. In this case, the original source material has a bit depth of 10 bits. This is encoded according to aspects of the present invention. This bitstream can then be decoded at both the original 10 bits, as well as an approximate version at 8 bits. Note that at low bit rates the R-D curves for both cases are nearly identical. Then, as the rate-distortion curves approach the round-off threshold for 8 bits (˜59 dB as shown in Table 1), the 8-bit curve begins to fall away leaving only the 10-bit curve to achieve the higher PSNRs. The more limited range of QP values at 8 bits causes its curve to terminate at lower PSNR and bit rate.
[0059] As mentioned above, as 8-bit decoding of some quantized value differs only from the corresponding 10-bit decoding by round-off error. This round-off error can accumulate from prediction to prediction, i.e. P-frames. This error results in a MSE between the 8-bit and 10-bit decodings, which is known as drift. This drift typically is neither noticeable nor objectionable in normal practice (i.e. I-frame spacing). In the case where the decoded bit depth, M, is greater than the input (encoding) bit depth, N, the resulting drift can be eliminated by sending N in the bitstream, and then emulating the coarser arithmetic of an N-bit decoder.
Implementation
[0060] The invention may be implemented in hardware or software, or a combination of both (e.g., programmable logic arrays). Unless otherwise specified, the algorithms included as part of the invention are not inherently related to any particular computer or other apparatus. In particular, various general-purpose machines may be used with programs written in accordance with the teachings herein, or it may be more convenient to construct more specialized apparatus (e.g., integrated circuits) to perform the required method steps. Thus, the invention may be implemented in one or more computer programs executing on one or more programmable computer systems each comprising at least one processor, at least one data storage system (including volatile and non-volatile memory and/or storage elements), at least one input device or port, and at least one output device or port. Program code is applied to input data to perform the functions described herein and generate output information. The output information is applied to one or more output devices, in known fashion.
[0061] Each such program may be implemented in any desired computer language (including machine, assembly, or high level procedural, logical, or object oriented programming languages) to communicate with a computer system. In any case, the language may be a compiled or interpreted language.
[0062] Each such computer program is preferably stored on or downloaded to a storage media or device (e.g., solid state memory or media, or magnetic or optical media) readable by a general or special purpose programmable computer, for configuring and operating the computer when the storage media or device is read by the computer system to perform the procedures described herein. The inventive system may also be considered to be implemented as a computer-readable storage medium, configured with a computer program, where the storage medium so configured causes a computer system to operate in a specific and predefined manner to perform the functions described herein.
[0063] A number of embodiments of the invention have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. For example, some of the steps described above may be order independent, and thus can be performed in an order different from that described. Accordingly, other embodiments are within the scope of the following claims. | The quantization parameter QP is well-known in digital video compression as an indication of picture quality. Digital symbols representing a moving image are quantized with a quantizing step that is a function QSN of the quantization parameter QP, which function QSN has been normalized to the most significant bit of the bit depth of the digital symbols. As a result, the effect of a given QP is essentially independent of bit depth a particular QP value has a standard effect on image quality, regardless of bit depth. The invention is useful, for example, in encoding and decoding at different bit depths, to generate compatible, bitstreams having different bit depths, and to allow different bit depths for different components of a video signal by compressing each with the same fidelity (i.e., the same QP). | 7 |
BACKGROUND
1. Technical Field
The disclosure generally relates to gas turbine engines.
2. Description of the Related Art
Gas turbine engines, particularly those for military use, typically are designed to accommodate either the desire for aircraft speed (e.g., supersonic capability) or on-station time (i.e., loiter capability). In this regard, turbojet engines are commonly used to accommodate high aircraft speed, whereas turbofan and turboprop engines are commonly used to accommodate increased range or high on-station time.
SUMMARY
Gas turbine engine systems involving tip fans are provided. In this regard, an exemplary embodiment of a gas turbine engine system comprises: a multi-stage fan having a first rotatable set of blades and a second counter-rotatable set of blades, the first rotatable set of blades defining an inner fan and a tip fan; and an epicyclic differential gear assembly operative to receive a torque input and differentially apply the torque input to the first set of blades and the second set of blades.
An exemplary embodiment of a gas turbine engine system comprises: a tip fan having a first rotatable set of blades; a second rotatable set of blades located downstream of the first set of blades; and a differential gear assembly operative to receive a torque input and differentially apply the torque input to the first set of blades and the second set of blades.
An exemplary embodiment of a gas turbine engine comprises: a first annular gas flow path; a second annular gas flow path located radially outboard of the first gas flow path; a third annular gas flow path located radially outboard of the second gas flow path; a first rotatable set of blades operative to interact with gas moving along the first gas flow path, the second gas flow path and the third gas flow path; a second rotatable set of blades located downstream of the first set of blades and operative to interact with gas moving along the first gas flow path and the second gas flow path; and a differential gear assembly operative to receive a torque input and differentially apply the torque input to the first set of blades and the second set of blades.
Other systems, methods, features and/or advantages of this disclosure will be or may become apparent to one with skill in the art upon examination of the following drawings and detailed description. It is intended that all such additional systems, methods, features and/or advantages be included within this description and be within the scope of the present disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
Many aspects of the disclosure can be better understood with reference to the following drawings. The components in the drawings are not necessarily to scale. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views.
FIG. 1 is a schematic diagram depicting an exemplary embodiment of a gas turbine engine.
FIG. 2 is a schematic diagram depicting another exemplary embodiment of a gas turbine engine.
DETAILED DESCRIPTION
Gas turbine engine systems involving tip fans are provided, several exemplary embodiments of which will be described in detail. In this regard, some embodiments of a gas turbine engine system incorporate the use of a fan that can adapt to a variety of operating conditions, such as supersonic and sub-sonic loiter conditions. In some embodiments, the fan is a multi-stage fan that incorporates a tip fan and is driven by a differential gear assembly. Notably, the differential gear assembly enables stages of the multi-stage fan to exhibit different rotational speeds.
In this regard, reference is made to FIG. 1 , which schematically depicts an exemplary embodiment of a gas turbine engine system. As shown in FIG. 1 , system 100 incorporates a multi-stage fan 102 that includes a forward fan stage 104 and a rear fan stage 106 . Notably, the forward fan stage incorporates an inner fan 108 and a tip fan 109 . Specifically, each of the blades of the forward fan stage includes distal end portions that form the tip fan. Each of the fan stages includes a corresponding set of rotatable blades, with each of the sets of blades being powered by a differential gear assembly 110 .
Differential gear assembly 110 is coupled to a low-pressure turbine 112 via shaft 114 . In addition to providing torque for rotating the multi-stage fan, low-pressure turbine 112 powers a low-pressure compressor 116 . Low-pressure turbine 112 is located downstream of a high-pressure turbine 118 that is connected through shaft 120 to a high-pressure compressor 122 . A combustor 130 is located downstream of the high-pressure compressor and upstream of the high-pressure turbine.
Low-pressure compressor 116 , high-pressure compressor 122 , combustor 130 , high-pressure turbine 118 and low-pressure turbine 112 are located along an annular gas flow path 140 . Gas flow path 140 also receives a flow of gas from multi-stage fan 102 . However, gas from multi-stage fan 102 also is directed along an annular gas flow path 142 (e.g. a primary bypass stream), which is located radially outboard of gas flow path 140 , and along an annular gas flow path 144 (e.g., a secondary bypass stream), which is located radially outboard of gas flow path 142 . Specifically, tip fan 109 is positioned along gas flow path 144 .
In operation, the differential gear assembly enables rotational speeds of the fan stages of the multi-stage fan to accommodate various operational requirements. By way of example, for high-speed flight operations, the forward fan stage can be set to a relatively high rotational speed while the rotational speed of the rear fan stage is set to a lower rotational speed. Notably, achieving a desired rotational speed can be accomplished by altering the pitch and/or camber of the blades of one or more of the fan stages. For instance, by increasing the pitch and/or camber of the blades of the forward fan stage, fan stage work and fan pressure ratio of the forward fan stage is increased, which causes a corresponding decrease in rotational speed of the forward fan stage. Responsive to this speed decrease, the differential gear assembly causes the rotational speed of the rear fan stage to increase.
With respect to low-speed operations, the forward fan stage can be controlled via pitch and/or camber change to exhibit a higher fan pressure ratio and corresponding reduced rotational speed, whereas the rear fan stage can exhibit a lower fan pressure ratio and a corresponding higher rotational speed. In transitioning to high-speed operations, the pitch and/or camber of the blades of the forward fan stage can be decreased, which causes a corresponding increase in rotational speed of the forward fan stage and an increase in rotational speed of the rear fan stage.
Additionally or alternatively, the tip fan 109 can be used to influence high-speed and low-speed operations. In addition, the flow characteristics of the secondary bypass stream 144 can be used separately, or in concert with the primary bypass stream 142 to affect exhaust system cooling and/or engine or vehicle thermal management. In this regard, high rotational speed typically is exhibited by the forward fan stage during high-speed operations. In this mode of operation, airflow to the tip fan can be restricted. As such, the tip fan is not able to perform a high degree of work and, therefore, the tip fan does not significantly reduce the rotational speed of the forward fan stage. In contrast, for low-speed operations in which slower rotational speed of the forward fan stage typically is exhibited, airflow to the tip fan can be increased. This tends to slow the forward fan stage and reduces the pressure ratio across the forward fan stage.
It should be noted that the embodiment of FIG. 1 includes two fan stages that are configured to exhibit different rotational speeds. In other embodiments, various other numbers of stages can be used. In some of these embodiments, two or more of the stages can be controlled to exhibit the same rotational speed.
FIG. 2 is a schematic diagram depicting another embodiment of a gas turbine engine system. As shown in FIG. 2 , system 200 includes a multi-stage fan that incorporates a forward fan stage 202 and a rear fan stage 204 . Notably, the forward fan stage incorporates an inner fan 203 and a tip fan 205 . Each of the fan stages includes a corresponding set of rotatable blades, with first and second sets of blades ( 206 , 208 ) of a low-pressure compressor 210 being located between the fan stages.
Each of the blades of the forward fan stage includes distal end portions that form the tip fan. Each of the blades of the rear fan stage includes an inner portion, which is located along an annular inner gas flow path 212 , and an outer portion, which is located along an annular outer gas flow path 214 (located radially outboard of gas flow path 212 ). For instance, blade 212 includes an inner portion 216 located along gas flow path 212 and an outer portion 218 located along gas flow path 214 . The first and second sets of blades ( 206 , 208 ) of the low-pressure compressor are located along inner gas flow path 212 , whereas the tip fan is located along an annular gas flow path 219 (located radially outboard of gas flow path 214 ).
Each of the sets of blades of the multi-stage fan and of the low-pressure compressor is powered by an epicyclic differential gear assembly 220 . The differential gear assembly is coupled to a low-pressure turbine 222 via shaft 224 . Low-pressure turbine 222 is located downstream of a high-pressure turbine 228 that is connected through shaft 230 to a high-pressure compressor 232 . A combustor 234 is located downstream of the high-pressure compressor and upstream of the high-pressure turbine.
In the embodiment of FIG. 2 , differential gear assembly 220 incorporates a forward epicyclic gear 240 and a rear epicyclic gear 250 . The forward epicyclic gear includes a carrier 242 , planet gears (e.g., planet gear 244 ) held by the carrier, a ring gear 246 surrounding the planet gears, and a sun gear 248 about which the planet gears rotate. The rear epicyclic gear includes a carrier 252 , planet gears (e.g., planet gear 254 ) held by the carrier and a ring gear 256 surrounding the planet gears. Notably, the rear epicyclic gear and the forward epicyclic gear share sun gear 248 .
In operation, the first and second sets of blades ( 206 , 208 ) of the low-pressure compressor rotate with corresponding sets of blades of the fan stages. Specifically, the forward fan stage 202 (i.e., the inner fan and the tip fan) and first set of compressor blades 206 rotate with carrier 242 of the forward epicyclic gear. In contrast, the rear fan stage 204 and second set of compressor blades 208 rotate with ring gear 246 of the forward epicyclic gear. Note that the fan stages, and thus the first and second set of compressor blades, are counter-rotating.
In operation, the differential gear assembly enables rotational speeds of the multi-stage fan and the low-pressure compressor to accommodate various operational requirements. By way of example, for high-speed flight operations, the forward fan stage and first set of compressor blades can be set to a relatively high rotational speeds, while the rotational speeds of the rear fan stage and second set of compressor blades can be lower.
Achieving a desired rotational speed can be accomplished by altering the flow of air to the tip fan. For instance, by increasing the flow of air to the tip fan, fan pressure ratio of the first stage fan is increased, which causes a corresponding decrease in rotational speeds of the first stage fan and the first set of compressor blades. Responsive to this speed decrease, the differential gear assembly causes the rotational speeds of the rear stage fan and the second set of compressor blades to increase.
With respect to low-speed operations, the forward fan stage can be controlled to exhibit a higher fan pressure ratio, which results in corresponding reduced rotational speeds of the forward fan stage and the first set of compressor blades. Responsive to these reduced speeds, the rear fan stage can exhibit a higher rotational speed (which also is exhibited by the second set of compressor blades) and a corresponding lower fan pressure ratio. Notably, the counter-rotating configuration embodied provides high relative velocities between adjacent low pressure compressor blades resulting in relatively high levels of pressure ratio. This counter-rotating arrangement allows for a preservation of core supercharging and thermodynamic efficiency as fan speeds are modulated through the epicyclic differential gearbox.
In transitioning to high-speed operations, the flow of air to the tip fan can be decreased, which causes a corresponding increase in rotational speeds of the first stage fan and the first set of compressor blades. This can be accomplished by selectively closing one or more valves (e.g., valve 262 ) of an inlet valve assembly 260 . In this embodiment, the inlet valve assembly includes an annular arrangement of valves that can be controlled to alter airflow to the tip fan. It should be noted that, in transitioning to slower speeds, spillage drag oftentimes is experienced by gas turbine engines as the need for intake air required by the engine for reduced thrust reduces quicker, and to a level ultimately lower, than the aircraft inlet's ability to deliver flow to the engine. During such a transition, inlet valve assembly 260 can be adjusted to an open position. In the open position, excess air, which could otherwise cause spillage drag, could be diverted from gas flow path 219 to gas flow path 214 .
With respect to low-speed operations, one or more valves of inlet valve assembly 260 can be maintained in the open position. As such, an increased flow of air is provided to the tip fan, which causes the work of the forward fan stage to increase. Responsive to the increase in work, rotational speed of the forward fan stage slows, which causes a corresponding increase in the rotational speed of the rear fan stage as described above.
It should be emphasized that the above-described embodiments are merely possible examples of implementations set forth for a clear understanding of the principles of this disclosure. Many variations and modifications may be made to the above-described embodiments without departing substantially from the spirit and principles of the disclosure. All such modifications and variations are intended to be included herein within the scope of this disclosure and protected by the accompanying claims. | Gas turbine engine systems involving tip fans are provided. In this regard, a representative gas turbine engine system includes: a multi-stage fan having a first rotatable set of blades and a second counter-rotatable set of blades, the first rotatable set of blades defining an inner fan and a tip fan; and an epicyclic differential gear assembly operative to receive a torque input and differentially apply the torque input to the first set of blades and the second set of blades. | 5 |
SUMMARY OF THE INVENTION
This invention relates to a flexible high energy coaxial cable for conducting an electric current in the range of 1 to 500 kiloamperes, wherein a high voltage conductor is surrounded by high voltage insulation. A first braided wire tube is positioned to surround the insulation and a first flexible reinforcing layer is positioned to surround the first braided wire tube. A second braided wire tube surrounds the first reinforcing layer and a second flexible reinforcible layer surrounds the second braided wire tube. An outer flexible insulation layer surrounds the second flexible reinforcing layer and the cable has a first end connector at one end in electrical contact with the high voltage conductor and a second end connector at the opposite end in electrical contact with the high voltage conductor.
In another aspect of the invention, the high energy coaxial cable has a minimum bend radius of substantially 11 1/2 inches and includes a high voltage center conductor for conducting current up to 500 kiloamperes. A layer of high voltage insulation surrounds the center conductor and a first braided wire tube surrounds the insulation. A first reinforcing wrap surrounds the first braided wire tube and the second braided wire tube surrounds the first reinforcing wrap. The first and second braided wire tubes are in electric contact with each other at the ends thereof. A second reinforcing wrap is placed surrounding the second braided wire tube and first and second end connectors are attached to opposing ends of the high voltage center conductor. First and second return connectors are isolated from the first and second end connectors and surround the high voltage insulation adjacent to the ends of the cable. Clamping is provided surrounding the second braided wire tubes at the ends thereof for holding the wire tubing in contact with the first and second return connectors. A flexible outer insulation layer surrounds the clamping means and the second reinforcing wrap.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross section of an old art high current conducting coaxial cable.
FIG. 2 is a cross section of the high energy flexible coaxial cable of the present invention.
FIG. 3 is a section view along the length of the high energy flexible coaxial cable of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Electrothermal chemical (ETC) guns require large amounts of energy to initiate firing. Such energy must be transferred to the gun in very short periods of time resulting in large electrical currents. It is not uncommon for such guns to require several hundred thousand amperes for firing. It is difficult to pass such large electrical currents through conductors connecting a pulse power supply to the gun without destroying the conductors. Destruction of conductors under these circumstances is due to the strong magnetic forces generated by the large electrical currents. Several conductor configurations have been used in the past to attempt to carry high current. Such conductor configurations were constructed to minimize the magnetic forces on the conductors. One such configuration is a parallel plate conductor plate configuration in which the conductors are plate-like and parallel to each other, separated by insulating material and carry the current in alternate directions. Another design used in the past is the coaxial configuration in which one conductor is placed inside another hollow conductor which is shaped in the form of a tube. The tubular or outer conductor is separated from the inner conductor by an insulating material which is wrapped around the inner conductor. The coaxial configuration has an advantage in that the magnetic field outside the outer conductor is 0. Thus, no magnetic forces are exerted on any metallic object in the immediate surroundings of the cable. While such a configuration provides a magnetic field free environment on the outside of the conductor cable, the space in between the two conductors experiences a very strong magnetic field. As a result, a force is exerted outwards on the outer conductor on every element of the outer conductor, wherein the force per unit area of the outer conductor is referred to as magnetic pressure. Such magnetic pressure is similar to the air pressure that is exerted against the inside surface of an inflated automobile tire. Thus, when a high current is passed through coaxial cable, the outer conductor experiences the same forces as are experienced by a tube filled with a high pressure fluid. As a result, the outer conductor in a coaxial cable may be literally "blown out" when the cable carries currents at levels of several hundred thousand amperes. Initially, the designers of such coaxial cables used copper tubes as the outer conductors in the coaxial cable. Such a configuration is useful as long as there is no relative movement between a system power supply and the portion of the system which must receive the high current pulse. However, when a large gun fires, it recoils up to two feet or more and therefore inflexible coaxial energy transfer lines cannot be used. One of the more recent coaxial line designs may be seen in FIG. 1 of the drawings wherein a central polyethylene rod 11 is surrounded by a tubular inner conductor 12. An insulation layer 13 surrounds the inner conductor 12 and a tubular outer conductor 14 is depicted surrounding the insulation layer. An outer insulation layer 16 is depicted surrounding the outer conductor. The cable of FIG. 1 has severe limitations inasmuch as current carrying capacity and cable flexibility are inadequate for most ETC gun applications. The large polyethylene core 11 limits minimum bend radius to greater than 32 inches and there is not sufficient mechanical confinement for the high magnetic pressures induced at high current levels to the conductors. Known coaxial cables of the type of FIG. 1 have been found to have current carrying capabilities less than 25 kiloamperes. Moreover, the coaxial cable design of FIG. 1 severely complicates the task of constructing end connectors for the current carrying inner and outer conducting tubes 12 and 14 respectively.
The present invention relates to the construction of a coaxial cable which is capable of carrying currents up to five hundred thousand amperes without suffering mechanical damage from the magnetic pressures resulting therefrom. Furthermore, the coaxial cable at the same time is sufficiently flexible so that it may be used in ETC gun firing applications.
With reference now to FIG. 2 of the drawings, it may be seen that an inner force/zero conductor 17 (4/0 wire size) is provided which is surrounded by high voltage insulation 18. A double layered braided wire tube 19 surrounds the insulation 18 and a high tensile strength tape 21 is wrapped around the double layered braided wire tube 19. An outer doubled layered braided wire tube 22 surrounds the high tensile strength reinforcing tape layer 21 and an outer high tensile strength reinforcing tape wrap 23 is applied around the outer braided wire tube. A shrink wrap tubing 24 is positioned around the layered construction just described. It should be noted that the section of the high energy flexible coaxial cable described in conjunction with FIG. 2 is taken through a portion of the cable removed from either end where end connectors are positioned on the cable and are hereinafter described.
In the drawing of FIG. 3 the high energy coaxial flexible cable of the present invention is shown with the center length portion of the cable broken away. The cable as used in ETC gun firing applications by the inventors to date have been up to 55 feet long. It should be recognized that longer or shorter cable length are included within the boundaries of this disclosure as long as the cable length is sufficient to afford the desired flexibility in the cable. Flexibility of the cable in this invention affords a minimum bend radius of about eleven and one half inches. At the left end of the cable shown in FIG. 3 is a power supply end connector shown generally at 26 on the coaxial cable of the present invention. An electrically conductive connector 27, of some material such as copper, is shown having a bore 28 therein for receiving the end of the center conductor 17. Two holes 29 are drilled along a diameter of the power supply end connector 27 and through the center conductor 17. A pin 31 is placed within each of the holes 29 and secured therein to firmly hold the power supply end connector on the end of the flexible coaxial cable described herein.
An insulator 32 is positioned around the insulation 18 for the center conductor 17 adjacent to the power supply end connector 27. A return conductor connector 33 is positioned surrounding the insulation 18 abutting the end of the insulator 32 and thereby being spaced from the power supply end connector 27. Return conductor connector 33 is provided made of some conductive material such as copper or aluminum. The inner and outer double layered braided wiring tubes 19 and 22 respectively, are placed in electrical contact with one another at the power supply end and are positioned surrounding a smaller diameter on the return conductor connector 33 as shown at the left end of FIG. 3. A series of magnetically shrunk clamps 34, four clamps in this embodiment, are shown surrounded by the outer heat shrink tubing insulation layer 24 to securely hold the tubular braided wire return connectors 19 and 22 in contact with each other and the return conductor connector 33. A magniflex machine manufactured by Maxwell Labs., San Diego, Calif. may be used to magnetically shrink or crimp the clamps 34. The clamps 34 are copper bands or may be any other electrically conductive bands to utilize the magnetic clamping feature. Alternatively, some type of hose clamp could be used to mechanically secure the double layered braided wire tubular return conductors 19 and 22 to the return conductor connector 33.
On the opposite or gun end of the high energy flexible coaxial cable the gun end return conductor connector 36 is shown surrounding the high voltage insulation 18 for the center conductor 17. The return conductor connector 36 like the supply end return conductor connector 33 is made of some electrically conductive material such as copper or aluminum. The connector 36 has a small diameter which fits beneath the double layered braided wire tubes 19 and 22 as shown in FIG. 3. The braided wire tubes 19 and 22 are joined together electrically in the area surrounding the smaller diameter of the return conductor connector 36 and are held firmly in place thereagainst by the magnetically shrunk clamps 34 or some other clamping device described hereinbefore. A gun end connector insulator 37 is shown disposed adjacent to the return conductor connector 36 and is positioned surrounding the high voltage insulation 18. Adjacent to the insulator 37 and spaced from the return conductor connector 36 is a gun end connector 38 which has a bore 39 in one end thereof. As in the power supply end connector 27, a pair of holes 41 are drilled through a diameter of the gun end connector 38 and a pin 42 is inserted in each of the holes 41 to fit tightly therein and secure the gun end of the high current conductor 17 within the gun end connector 38. An additional bore 43 is drilled into the gun end connector 38 at the end thereof opposite the end having the bore 39 therein. A slot 44 is cut across the diameter of the gun end connector 38 and a series of threaded holes 46 is placed parallel to but spaced from the diameter of the gun end connector to receive screws 47 extending through aligned clearance holes 48. As a result, a conductor similar to conductor 17 may be inserted in the bore 43 at the breech of a gun and clamped into the gun end connector 38 by advancing the screws 47 in the threads 46. An insulated wire voltage probe 49 is shown at the gun end connector for monitoring purposes.
As a result a high energy flexible coaxial cable is provided which is useful for providing high energy electrical pulses between a fixed power supply and a moving breech of an ETC gun, thereby solving the problem associated with delivering high energy pulses to gun systems which recoil or must be able to accommodate variable barrel elevations to accommodate various angles of fire. Current as high as 300 kiloamperes at 20 kilovolts has been transmitted through the disclosed coaxial cable and the design is deemed to be capable of carrying currents as high as 500 kiloamperes. The double layered tubular braided wire provides the cable flexibility while maintaining a current return flow path within the cable. The reinforcing tapes help contain high magnetic pressures associated with high currents and also provides for the flexibility of the coaxial cable and high voltage standoff capability. Kevlar (tm) tape is utilized in the reinforcing tape wraps 21 and 23 for currents above 250 kiloamperes and fiberglass wrapping tape has been used in the coaxial cable of the present invention for current levels below the 250 kiloampere level. The Kevlar wraps for the layers 21 and 23 of FIG. 2 provide greater strength for retaining the magnetic pressures experienced at the higher current levels while the fiberglass tape wraps for layers 21 and 23 appear to be sufficient for pressures due to currents below the 250 kiloampere level. In both instances the flexibility of the high energy coaxial cable disclosed herein is sufficient to obtain the 111/2 inch bend radius mentioned hereinbefore.
Although the best mode contemplated for carrying out the present invention has been herein shown and described, it will be apparent that modification and variation may be made without departing from what is regarded to be the subject matter of the invention:
HMS:lu | A high energy coaxial cable is disclosed which is flexible to the extent of allowing a bend radius as short as 11 1/2 inches. The cable will conduct up to 500 kiloamperes and is reinforced to resist the high magnetic forces within the cable caused by the high current conducted. The cable is therefore useful in coupling high current between parts which experience relative movement such as a stationary power supply and a recoiling gun breech. | 7 |
This is a division, of application Ser. No. 801,488 filed May 31, 1977 now U.S. Pat. No. 4,125,625 which in turn is a continuation-in-part of U.S. Ser. No. 697,296 filed June 17, 1976 and now U.S. Pat. No. 4,057,556.
BACKGROUND OF THE INVENTION
(a) Field of the Invention
This invention relates to novel tropone derivatives, to processes for their preparation, to methods for using said derivatives, and to therapeutically acceptable salts and compositions of said derivatives.
More specifically, the present invention relates to novel troponyl-oxamic acid derivatives possessing valuable pharmacologic properties. For example, these derivatives are useful for preventing or treating allergic conditions in a mammal at dosages which do not elicit undesirable side effects. The combination of these pharmacologic properties render the troponyl-oxamic acid derivatives of the invention therapeutically useful.
(b) Description of the Prior Art
A rather large number of reports dealing with tropone derivatives are available. The prior art relating to tropone derivatives is summarized in various reviews; for example, see the review by F. Pietra in Chem. Rev., 73, 293 (1973). Another report describes a class of alkyl esters of 5-aminotropolones which exhibit anti-neoplastic activity, see L. D. Donaruma, Canadian Pat. No. 787,451, issued June 11, 1968.
The tropone derivatives of the present invention are distinguished from the prior art compounds by the nature of the substituents on the tropone nucleus and by their pharmacologic properties. More specifically, the novel tropone derivatives of this invention are distinguished from the prior art compounds by having the tropone nucleus substituted with one or two oxamic acid derivatives.
SUMMARY OF THE INVENTION
The compounds of this invention are represented by formula I ##STR1## in which R 1 and R 4 are the same or different selected from the group consisting of hydrogen, halo, trifluoromethyl, lower alkoxy, lower alkyl, phenyl, hydroxy, phenoxy, mercapto, (2-carboxyphenyl)thio, NR 7 R 8 wherein R 7 and R 8 each is hydrogen or lower alkyl or R 7 is alkyl and R 8 is p-toluenesulfonyl, and a radical of formula NR 9 COR 10 wherein R 9 is hydrogen or lower alkyl and R 10 is carboxy, lower alkoxycarbonyl, hydrazinocarbonyl or a radical of formula COO(CH 2 ) n COR 11 wherein n is an integer from one to six and R 11 is hydroxy or lower alkoxy; and R 2 , R 3 , R 5 and R 6 are the same or different selected from the group consisting of hydrogen, halo, trifluoromethyl, lower alkoxy, lower alkyl, phenyl, hydroxy, phenoxy, mercapto, (2-carboxyphenyl)thio, and NR 7 R 8 wherein R 7 and R 8 each is hydrogen or lower alkyl; or R 7 is lower alkyl and R 8 is p-toluenesulfonyl; with the proviso that at least one of R 1 and R 4 must be a radical of formula NR 9 COR 10 wherein R 9 and R 10 are as defined herein.
A preferred group of compounds of formula I are those in which R 10 is hydrazinocarbonyl or a radical of formula COO(CH 2 ) n COR 11 wherein n is an integer from one to six and R 11 is hydroxy or lower alkoxy.
Still another preferred group of compounds of this invention are represented by formula I in which R 1 is a radical of formula NR 9 COR 10 in which R 9 is hydrogen and R 10 is hydrazinocarbonyl or a radical of formula COO(CH 2 ) n COR 11 wherein n is an integer from one to six and R 11 is hydroxy or lower alkoxy; and R 2 , R 3 , R 4 , R 5 and R 6 are hydrogen.
Another preferred group of compounds of this invention is represented by formula I in which
(a) R 1 is a radical of formula NR 9 COR 10 in which R 9 is hydrogen or lower alkyl and R 10 is carboxy, lower alkoxycarbonyl, hydrazinocarbonyl or a radical of formula COO(CH 2 ) n COR 11 wherein n is an integer from one to six and R 11 is hydroxy or lower alkoxy; and R 2 , R 3 , R 4 , R 5 and R 6 are the same or different selected from the group consisting of hydrogen, lower alkoxy and hydroxy; or
(b) R 4 is a radical of formula NR 9 COR 10 in which R 9 is hydrogen or lower alkyl and R 10 is carboxy, lower alkoxycarbonyl, hydrazinocarbonyl or a radical of formula COO(CH 2 ) n COR 11 wherein n is an integer from one to six and R 11 is hydroxy or lower alkoxy; and R 1 , R 2 , R 3 , R 5 and R 6 are the same or different selected from the group consisting of hydrogen, lower alkoxy and hydroxy; or
(c) R 1 and R 4 are a radical of formula NR 9 COR 10 wherein R 9 is hydrogen or lower alkyl and R 10 is carboxy, lower alkoxycarbonyl, hydrazinocarbonyl or a radical of formula COO(CH 2 ) n COR 11 wherein n is an integer from one to six and R 11 is hydroxy or lower alkoxy; and R 2 , R 3 , R 5 and R 6 are the same or different selected from the group consisting of hydrogen, lower alkoxy and hydroxy.
Still another preferred group of compounds of this invention are represented by formula I in which
(a) R 1 is a radical of formula NR 9 COR 10 in which R 9 is hydrogen or lower alkyl and R 10 is carboxy, lower alkoxycarbonyl, hydrazinocarbonyl or a radical of formula COO(CH 2 ) n COR 11 wherein n is an integer from one to six and R 11 is hydroxy or lower alkoxy; and R 2 , R 3 , R 4 , R 5 and R 6 are the same or different selected from the group consisting of hydrogen, lower alkoxy and hydroxy, with the proviso that at least three of R 2 , R 3 , R 4 , R 5 and R 6 are hydrogen or
(b) R 4 is a radical of formula NR 9 COR 10 in which R 9 is hydrogen or lower alkyl and R 10 is carboxy, lower alkoxycarbonyl, hydrazinocarbonyl or a radical of formula COO(CH 2 ) n COR 11 wherein n is an integer from one to six and R 11 is hydroxy or lower alkoxy; and R 1 , R 2 , R 3 , R 5 and R 6 are the same or different selected from the group consisting of hydrogen, lower alkoxy and hydroxy, with the proviso that at least three of R 1 , R 2 , R 3 , R 5 and R 6 are hydrogen; or
(c) R 1 and R 4 are a radical of formula NR 9 COR 10 wherein R 9 is hydrogen of lower alkyl and R 10 is carboxy, lower alkoxycarbonyl, hydrazinocarbonyl or a radical of formula COO(CH 2 ) n COR 11 wherein n is an integer from one to six and R 11 is hydroxy or lower alkoxy; and R 2 , R 3 , R 5 and R 6 are the same or different selected from the group consisting of hydrogen, lower alkoxy and hydroxy, with the proviso that at least two of R 2 , R 3 , R 5 and R 6 are hydrogen.
The therapeutically acceptable salts of the compounds of formula I are also included within the scope of this invention.
The compounds of this invention of formula I are prepared by a process comprising: condensing a compound of formula II ##STR2## in which R 12 and R 15 are the same or different selected from the group consisting of hydrogen, halo, trifluoromethyl, lower alkoxy, lower alkyl, phenyl, hydroxy, phenoxy, mercapto, (2-carboxyphenyl)thio, NR 7 R 8 wherein R 7 is lower alkyl and R 8 is hydrogen, lower alkyl or p-toluenesulfonyl, and NHR 9 wherein R 9 is hydrogen or lower alkyl: and R 13 , R 14 , R 16 and R 17 are the same or different selected from the group consisting of hydrogen, halo, trifluoromethyl, lower alkoxy, lower alkyl, phenyl, hydroxy, phenoxy, mercapto, (2-carboxyphenyl)thio, and NR 7 R 8 wherein R 7 is lower alkyl and R 8 is hydrogen, lower alkyl or p-toluenesulfonyl; with the proviso that at least one of R 11 and R 14 must be NHR 9 , with a compound of formula III
Halogen-COR.sup.10 (III)
in which R 10 is lower alkoxycarbonyl and the halogen is bromine, chlorine or iodine in the presence of a proton acceptor to obtain the corresponding compound of formula I in which R 1 and R 4 are the same or different selected from the group consisting of hydrogen, halo trifluoromethyl, lower alkoxy, lower alkyl, phenyl, hydroxy, phenoxy, mercapto, (2-carboxyphenyl)thio and NR 7 R 8 wherein R 7 is lower alkyl and R 8 is hydrogen, lower alkyl or p-toluenesulfonyl, and a radical of formula NR 9 COR 10 wherein R 9 is as defined herein and R 10 is lower alkoxycarbonyl; and R 2 , R 3 , R 5 and R 6 are the same or different selected from the group consisting of hydrogen, halo, trifluoromethyl, lower alkoxy, lower alkyl, phenyl, hydroxy, phenoxy, mercapto, (2-carboxyphenyl)thio and NR 7 R 8 wherein R 7 is lower alkyl and R 8 is hydrogen, lower alkyl or p-toluenesulfonyl; and, if desired and required, followed by transformation of the compound of formula I, prepared as described above, to other compounds of formula I by methods described herein.
Another aspect of this invention involves a pharmaceutical composition comprising a compound of formula I or a therapeutically acceptable addition salt thereof, and a pharmaceutically acceptable carrier therefor.
Still another aspect of this invention involves a method for preventing or treating allergic conditions in a mammal which comprises administering to said mammal an effective allergy alleviating amount of a compound of formula I or a therapeutically acceptable addition salt thereof.
DETAILED DESCRIPTION OF THE INVENTION
The term "lower alkyl" as used herein contemplates both straight and branched chain alkyl radicals containing from one to six carbon atoms and includes methyl, ethyl, propyl, isopropyl, butyl, isobutyl, pentyl, hexyl and the like.
The term "lower alkoxy" as used herein contemplates both straight and branched chain alkoxy radicals containing from one to six carbon atoms and includes methoxy, ethoxy, isopropoxy, butoxy, hexanoxy and the like.
The terms "halogen" as used herein contemplate halogens and include fluorine, chlorine, bromine and iodine, unless stated otherwise.
The term "lower alkanol" as used herein contemplates both straight and branched chain alkanols containing from one to six carbon atoms and includes methanol, ethanol, isopropanol, butanol, hexanol and the like.
The acidic compounds of formula I in which R 1 and/or R 4 is a radical of formula NR 9 COR 10 wherein R 10 is carboxy or a radical of formula COO(CH 2 ) n COR 11 wherein n is as defined herein and R 11 is hydroxy form salts with suitable therapeutically acceptable inorganic and orgaic bases. These derived salts possess the same activity as the parent acid and are included within the scope of this invention. The acid is transformed in excellent yield into the corresponding therapeutically acceptable salt by neutralization of said acid with the appropriate inorganic or organic base. The salts are administered in the same manner as the parent acid compounds. Suitable inorganic bases to form these salts include, for example, the hydroxides, carbonates, bicarbonates or alkoxides of the alkali metals or alkaline earth metals, for example, sodium, potassium, magnesium, calcium and the like. Suitable organic bases include the following amines; lower mono-, di- and trialkylamines, the alkyl radicals of which contain up to three carbon atoms, such as methylamine, dimethylamine, trimethylamine, ethylamine, di- and triethylamine, methylethylamine, and the like; mono, di- and trialkanolamines, the alkanol radicals of which contain up to three carbon atoms, for example, mono-, di- and triethanolamine; alkylene-diamines which contain up to six carbon atoms, such as hexamethylenediamine; cyclic saturated or unsaturated bases containing up to six carbon atoms, such as pyrrolidine, piperidine, morpholine, piperazine and their N-alkyl and N-hydroxyalkyl derivatives, such as N-methyl-morpholine and N-(2-hydroxyethyl)-piperidine, as well as pyridine. Furthermore, there may be mentioned the corresponding quaternary salts, such as the tetraalkyl (for example tetramethyl), alkyl-alkanol (for example methyltrimethanol and trimethyl-monoethanol) and cyclic ammonium salts, for example the N-methylpyridinium, N-methyl-N-(2-hydroxyethyl)morpholinium, N,N-dimethylmorpholinium, N-methyl-N-(2-hydroxyethyl)morpholinium, N,N-dimethylpiperidinium salts, which are characterized by havinggood water-solubility. In principle, however, there can be used all the ammonium salts which are physiologically compatible.
The transformations to the salts can be carried out by a variety of methods known in the art. For example, in the case of the inorganic salts, it is preferred to dissolve the acid of formula I in water containing at least one equivalent amount of a hydroxide, carbonate, or bicarbonate corresponding to the inorganic salt desired. Advantageously, the reaction is performed in a water-miscible, inert organic solvent, for example, methanol, ethanol, dioxane, and the like in the presence of water. For example, such use of sodium hydroxide, sodium carbonate or sodium bicarbonate gives a solution of the sodium salt. Evaporation of the solution or ddition of a water-miscible solvent of a more moderate polarity, for example, a lower alkanol, for instance, butanol, or a lower alkanone, for instance, ethyl methyl ketone, gives the solid inorgaic salt it that form is desired.
To produce an amine salt, the acid of formula I is dissolved in a suitable solvent of either moderate or lower polarity, for example, ethanol, methanol, ethyl acetate, diethyl ether and benzene. At least an equivalent amount of the amine corresponding to the desired cation is then added to that solution. If the resulting salt does not precipitate, it can usually be obtained in solid form by addition of a miscible diluent of low polarity, for example, benzene or petroleum ether, or by evaporation. If the amine is relatively volatile, any excess can easily be removed by evaporation. It is preferred to use substantially equivalent amounts of the less volatile amines.
Salts wherein the cation is quaternary ammonium are produced by mixing the acid of formula I with an equivalent amount of the corresponding quaternary ammonium hydroxide in water solution, followed by evaporation of the water.
The basic compounds of formula I in which R 1 , R 2 , R 3 , R 4 , R 5 and/or R 6 is NR 7 R 8 wherein R 7 and R 8 are as defined herein or R 1 and/or R 4 is a radical of formula NR 9 COR 10 wherein R 9 is as defined herein and R 10 is hydrazinocarbonyl form addition salts with suitable inorganic and organic acids. These salts possess the same activities as the parent base compound when administered to a mammal and may be utilized in the same manner. Suitable acids to form these salts include, for example the common mineral acids, hydrohalic, sulfuric or phosphoric, as well as the organic acids, formic, acetic, maleic, malic, citric, or tartaric acid, or acids which are sparingly soluble in body fluids and which impart slow-release properties to their respective salts such as pamoic or tannic acid or carboxymethyl cellulose. The addition salts thus obtained are the functional equivalent of the parent base compound in respect to their therapeutic use. Hence, these addition salts are included within the scope of this invention and are limited only by the requirement that the acids employed in forming the salts be therapeutically acceptable.
Also included within the scope of this invention are the isomers of the compounds of formula I resulting from the asymmetric centers contained therein.
Also included within the scope of this invention are the tautomeric forms of the compounds of formula I in which R 1 , R 2 , R 3 , R 4 , R 5 and/or R 6 is hydroxy resulting from the keto-enol equilibrium contained therein.
ANTI-ALLERGIC ACTIVITY
The compounds of this invention of formula I or therapeutically acceptable salts thereof are useful in the prevention or treatment of allergic reactions in a mammal upon oral or parenteral administration.
More specifically, the compounds of this invention are useful for the prophylactic treatment as well as for the management of anaphylactic reactions and atopic allergic manifestations, for example, bronchial asthma, hay fever, allergic rhinitis, allergic conjunctivitis, food allergies, urticaria and the like, in a sensitized mammal.
More specifically exemplified, the compounds of this invention are effective anti-allergic agents when tested using the passive cutaneous anaphylaxis (PCA) method, described by I. Mota, Immunology, 7, 681(1964). The anti-allergic activity of a given compound is measured in rats by its ability to inhibit the increase in vascular permeability at the site of injection of rat immunoglobulin E (IgE) followed by i.v. administration of the specific antigen. Evans blue is injected i.v. at the same time as the specific antigen, and the size of the wheal or of the area infiltrated with Evans blue is measured and compared with that of untreated controls. An effective anti-allergic agent will prevent or inhibit the release of inflammatory mediators (mainly serotonin and histamine from the mast cells) which causes an increase in vascular permeability and thus an infiltration of Evans blue surrounding the site of injection of IgE.
The anti-allergic activity of the compounds of formula I is demonstrated by the reduction of the wheal size of sensitized skin tissue compared to that of control animals. A comparison of the anti-allergic activity of the compounds of this invention with the anti-allergic activity of a standard compound, such as disodium cromoglycate, indicates that the compounds of this invention function in the same manner as disodium cromoglycate by blocking the release of mediators from the mast cells responsible for the allergic reaction.
When the compounds of formula I of this invention are used for suppressing allergic manifestations of anaphylactic reactions and atopic hypersensitivity in a mammal, they are used alone or in combination with pharmacologically acceptable carriers, the proportion of which is determined by the solubility and the chemical nature of the compound, chosen route of administration and standard biological practice. For example, they are administered parenterally by injection; orally; by the nasal route, for instance, as drops or aerosol; or by inhalation from an aerosol.
In addition, the compounds of this invention can be administered in conjunction with common anti-allergics, for example, known compounds effecting anti-histaminic, analgesic, central nervous system depressant, anti-hypertensive, immunosupressive, anti-bradykinin, anti-serotonin or endocrinological responses.
Therapeutic compositions containing the compounds of this invention are effective anti-allergic agents for preventing or relieving anaphylactic allergic manifestations at dosages of 0.1 mg to 100 mg/kg body weight when administered parenterally to a mammal. For administration to a mammal by parenteral injection, it is preferred to use the compounds of formula I in solution in a sterile aqueous vehicle which may also contain other solutes such as buffers or preservatives, as well as sufficient quantities of pharmaceutically acceptable salts or of glucose to make the solution isotonic.
A number of the compounds of this invention of formula I are useful in the management of allergic reactions when administered orally at dosages of 0.5 mg to 500 mg/kg body weight to a sensitized mammal. For example, the representative compounds of formula I,
[(2-oxo-3,5,7-cycloheptatrien-1-yl)amino] oxo-acetic acid ethyl ester (see Example 1),
[N-(2-oxo-3,5,7-cycloheptatrien-1-yl)-N-methylamino]oxo-acetic acid ethyl ester (see Example 1),
2,2'-[(2-oxo-3,5,7-cycloheptatrien-1,5-diyl)diimino]bis[2-oxo-acetic acid] diethyl ester (see Example 6),
[(2-oxo-3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic acid pentyl ester (see Example 31) and
[(5-methoxy-4-oxo-2,5,7-cycloheptatrien-1-yl)amino]oxo-acetic acid 1-methylethyl ester (see Example 31),
are effective anti-allergic agents when administered orally at dosages of 1.0 mg to 100 mg/kg body weight.
When the compounds of this invention are employed as antiallergic agents in mammals, e.g. rats, orally effective, anti-allergic amounts of the compounds are administered to the mammal, either alone or combined with pharmaceutically acceptable excipients in a dosage form, i.e. capsule or tablet, or the compounds are administere orally in the form of solutions or suspensions.
The tablet compositions contain the active ingredient in admixture with non-toxic pharmaceutical excipients known to be suitable in the manufacture of tablets. Suitable pharamaceutical excipients are, for example, starch, milk sugar, certain types of clay and so forth. The tablets may be uncoated or they may be coated by known techniques so as to delay disintegration and absorption in the gastrointestinal tract and thereby provide a sustained action over a longer period.
The aqueous suspensions of the invention contain the active ingredient in admixture with one or more non-toxic pharmaceutical excipients known to be suitable in the manufacture of aqueous suspensions. Suitable excipients are, for example, methylcellulose, sodium alginate, gum acacia, lecithin and so forth. The aqueous suspensions may also contain one or more preservatives, one or more coloring agents, one or more flavoring agents and one or more sweetening agents.
Non-aqueous suspensions may be formulated by suspending the active ingredient in a vegetable oil, for example, arachis oil, olive oil, sesame oil, or coconut oil, or in a mineral oil, for example liquid paraffin, and the suspension may contain a thicknening agent, for example beeswax, hard paraffin or cetyl alcohol. These compositions may also contain a sweetening agent, a flavoring agent and an anti-oxidant
The compounds of formula I can also be administered as nasal powders or insufflations. For such purpose the compounds are administered in finely divided solid form together with a pharmaceutically acceptable solid carrier, for example, a finely divided polyethylene glycol ("Carbowax 1540") or finely divided lactose. Such compositions may also contain other excipients in finely divided solid form, for instance, preservatives, buffers, or surface active agents.
When administering the compounds of this invention by inhalation from an aerosol, the compound of formula I is dissolved in water or ethanol and mixed with a volatile propellant, for example, dichlorotetrafluoroethane and dichlorodifluoromethane, and placed in a pressurized container having a metering valve to release a predetermined amount of material.
The dosage of the compounds of this invention will vary with the form of administration and the particular compound chosen. Furthermore, it will vary with the particular host under treatment. Generally, treatment is initiated with small dosages substantially less than the optimum dose of the compound. Thereafter, the dosage is increased by small increments until the optimum effect under the circumstance is reached. In general, the compounds of this invention are most desirably administered at a concentration level that will generally afford effective results without causing any harmful or deleterious side effects, and preferably at a level that is in a range of from about 0.1 mg to about 500 mg per kilogram body weight, per day although as aforementioned variations will occur. However, a dosage level that is in the range of from about 0.5 mg to about 200 mg per kilogram body weight per day is most desirably employed in order to achieve effective results.
Processes
Useful and practical starting materials for the preparation of the compounds of this invention of formula I are the tropone derivatives of formula II ##STR3## in which R 12 , R 13 , R 14 , R 15 , R 16 and R 17 are as defined in the first instance.
The tropone derivatives of formula Ii suitable as starting materials are described in a number of reports; for example, see the recent review on tropone derivatives, their preparation and their interconversions by F. Pietra, supra. Thus, the tropone derivatives suitable as starting materials are either known or they can be prepared by conventional means.
The compounds of this invention of formula I are prepared by condensing the compounds of formula 11 in which R 12 , R 13 , R 14 , R 15 , R 16 and R 17 are as defined in the first instance with one to ten molar equivalents, preferably one to three molar equivalents, of a compound of formula III.
Halogen-COR.sup.10 (III)
in which R 10 is lower alkoxycarbonyl and the halogen is bromine, chlorine or iodine in the presence of a proton acceptor to obtain the corresponding compound of formula I in which R 1 and R 4 are the same or different selected from the group consisting of hydrogen, halo, trifluoromethyl, lower alkoxy, lower alkyl, phenyl, hydroxy, phenoxy, mercapto, (2-carboxyphenyl)thio and NR 7 R 8 wherein R 7 is lower alkyl and R 8 is hydrogen, lower alkyl or p-toluenesulfonyl, and a radical of formula NR 9 COR 10 wherein R 9 is as defined herein and R 10 is lower alkoxycarbonyl; and R 2 , R 3 , R 5 and R 6 are the same or different selected from the group consisting of hydrogen, halo, trifluoromethyl, lower alkoxy, lower alkyl, phenyl, hydroxy, phenoxy, mercapto, (2-carboxyphenyl)thio and NR 7 R 8 wherein R 7 is lower alkyl and R 8 is hydrogen, lower alkyl or p-toluenesulfonyl.
In practicing the above condensation it is preferable to use an inert solvent as a reaction medium. Suitable solvents include benzene, toluene, chloroform, methylene chloride, lower alkyl ketones (i.e. 2-propanone, 2-butanone and 3-pentanone) and the like. However, if the reactants are mutually soluble, the solvent can be omitted without deleterious effects.
Suitable proton acceptors include the organic bases, or amines for instance, triethylamine, pyridine, N-ethylmorpholine, 1,5-diazabicyclo-[3.4.0]nonene-5 and the like, as well as the inorganic bases, preferably the alkali metal hydroxides, carbonates, hydrides, amides and alkoxides, for example, sodium ethoxide, sodium hydroxide, potassium hydroxide, potassium carbonate, sodium methoxide and the like. The preferred proton acceptors employed are the organic bases or amines. The amount of the organic bases can vary from one molar equivalent to a large molar excess. When a large molar excess is used, the organic base can also serve as the solvent for the condensation.
The duration and temperature of the condensation are not critical; however, the preferred time is from about ten minutes to about two days and the temperature can range from about -10° C. to 100° C. or the boiling point of the reaction mixture, preferably from about 20° C. to the boiling point of the reaction mixture. The compounds of formula I are separated from the reaction mixture by conventional means, for example, evaporation, filtration, extraction, chromatography and/or crystallization.
The compounds of formula I obtained from the above described condensation can be further reacted to obtain other compounds of formula I by methods described hereinafter.
For instance the compound of formula I in which at least one of R 1 , R 2 , R 3 , R 4 , R 5 and R 6 is lower alkoxy or halo can be reacted with a molar excess of ammonia or an amine of formula HNR 7 R 8 in which R 7 and R 8 are as defined herein to obtain the corresponding compound of formula I in which at least one of R 1 , R 2 , R 3 , R 4 , R 5 and R 6 is NR 7 R 8 in which R 7 and R 8 are as defined herein. The reaction is conducted either using the amine of formula HNR 7 R 8 as solvent or a suitable solvent can be selected from water and a lower alkanol (i.e. methanol, ethanol and the like). Suitable conditions for the reaction are a temperature of from about -50° C. to about 100° C., preferably 0° to 100° C., for about ten minutes to 12 hours. If the temperature necessary for reaction is above the boiling point of the reaction mixture, the reaction can be conducted at the desired temperature in a pressure vessel without deleterious effects.
The compound of formula I in which at least one of R 1 and R 4 is a radical of formula NR 9 COR 10 wherein R 9 is as defined herein and R 10 is lower alkoxycarbonyl, prepared as described above, can be reacted with hydrazine to obtain the corresponding hydrazide of formula I in which the corresponding R 1 and R 4 is a radical of formula NR 9 COR 10 wherein R 9 is as defined herein and R 10 is hydrazinocarbonyl. The hydrazinolysis in preferably achieved by reacting the compound of formula I with one to three molar equivalents of anhydrous hydrazine in an inert anhydrous organic solvent, for example methanol or ethanol, at 0° to 30° C. for two to ten hours and isolating the hydrazide of formula I from the reaction mixture.
The compound of formula I, prepared as above, in which at least one of R 1 and R 4 is a radical of formula NR 9 COR 10 wherein R 9 is as defined herein and R 10 is lower alkoxycarbonyl can be hydrolyzed to obtain the corresponding acidic compound of formula I in which the corresponding R 1 and R 4 is a radical of formula NR 9 COR 10 wherein R 9 is as defined herein and R 10 is carboxy. The preferred method of hydrolysis comprises the use of 0.1 to 2.0 molar equivalents, preferably 0.5 to 1.0 molar equivalents, of a mild alkali, for example a suitable mild alkali selected from the bicarbonates and acetates of sodium or potassium, in an inert solvent, for instance, water, a lower alkanol (i.e. methanol or ethanol) or mixtures thereof, at a temperature of about 20° to 120° C. for about one to ten hours. Acidification of the reaction mixture with a dilute mineral acid, such as hydrochloric acid, sulfuric acid, phosphoric acid and the like, gives the corresponding acidic compound of formula I.
In turn, if desired, the latter acidic compound of formula I in which at least one of R 1 and R 4 is a radical of formula NR 9 COR 10 wherein R 9 is as defined herein and R 10 is carboxy can be reacted with a compound of formula ω-halo-(CH 2 ) n --COR 11 wherein the halo is chloro, bromo or iodo, n is as defined herein and R 11 is lower alkoxy in the presence of a mild base to obtain the corresponding compound of formula I in which at least one of R 1 and R 4 is a radical of formula NR 9 COR 10 wherein R 9 is as defined herein and R 10 is a radical of formula COO(CH 2 ) n COR 11 wherein n is as defined herein and R 11 is lower alkoxy. For this reaction, about 0.5 molar equivalents of the mild base, preferably sodium or potassium carbonate, and about an equivalent molar quantity of the compound of formula ω-halo-(CH 2 ) n -COR 11 is required. The reaction is conducted in an inert organic solvent, preferably dimethyl sulfoxide, at 50° to 100° C. for one to five hours.
The compounds of formula I in which at least one of R 1 and R 4 is a radical of formula NR 9 COR 10 wherein R 9 is as defined herein and R 9 is a radical of formula COO(CH 2 ) n COR 11 wherein n is as defined herein and R 11 is hydroxy are readily obtained from the corresponding compound of formula I in which R 1 and/or R 4 is a radical of formula NR 9 COR 10 wherein R 9 is as defined herein and R 10 is a radical of formula COO(CH 2 ) n COR 11 wherein n is as defined herein and R 11 is t-butoxy by hydrolyzing the latter ester with an acid selected from a mineral acid or a strong organic acid. Suitable acids for this hydrolysis can be selected from 50 to 90% trifluoroacetic acid, 1 to 12 M hydrochloric acid, 0.5 to 10 M sulfuric acid and 1 to 12 M hydrogenchloride in anhydrous organic solvents at a temperature in the range of -30° to 30° C. The preferred reaction conditions for this hydrolysis consist of reacting the latter ester with 6 to 12 N hydrochloric acid at -30° to -10° C. for one to three hours and isolating the above mentioned acid of formula I in which R 10 is a radical of formula COO(CH 2 ) n COR 11 wherein R 11 is hydroxy.
In addition, a number of the compounds of formula I are readily converted to other compounds of formula I. In some cases it is convenient and preferable to prepare a specific compound of formula I by the transformation of another compound of formula I. Examples of each interconversions of the compound of formula I are described hereinafter.
For example, the acidic compound of formula I described above (i.e. R 1 and/or R 4 is a radical of formula NR 9 COR 10 wherein R 9 is as defined herein and R 10 is carboxy or R 10 is a radical of formula COO(CH 2 ) n COR 11 wherein R 11 is hydroxy) is readily esterified to obtain the corresponding ester of formula I (i.e. R 1 and/or R 4 is a radical of formula NR 9 COR 10 wherein R 9 is as defined herein and R 10 is lower alkoxycarbonyl or R 10 is a radical of formula COO(CH 2 ) n COR 11 wherein R 11 is lower alkoxy). Suitable esterification conditions include a variety of methods; for example, ester exchange, treatment with diazomethane or conversion of the acid to the corresponding activated carbonyl (i.e., acid halide, anhydride, succinimido, imidazolide and the like), followed by treatment of the latter with an appropriate lower alkanol, see also L. F. Fieser and M. Fieser, "Advanced Organic Chemistry", Reinhold Publishing Corporation, New York 1961, pp. 370-381
A preferred and convenient method of esterification comprises dissolving the acidic compound of formula I in an inert solvent, preferably dimethyl sulfoxide, in the presence of one to ten molar equivalents of a mild base, for example, sodium or potassium carbonate. One to three molar equivalents of a lower alkyl bromide or chloride is added and the solution is maintained at a temperature of about 20° to 100° C., preferably at about 40° to 80° C., for about 30 minutes to five hours.
The compound of formula I in which at least one of R 1 , R 2 , R 3 , R 4 , R 5 and R 6 is hydroxy can be alkylated to obtain the corresponding compound of formula I in which the corresponding R 1 , R 2 , R 3 , R 4 , R 5 and R 6 is alkoxy. The alkylation is conveniently carried out by reacting said hydroxy compound with one to five molar equivalents of a di(lower)alkyl sulfate in the presence of one to five molar equivalents of a mild alkali, for instance sodium or potassium carbonate in an inert solvent, for example, a lower alkyl ketone, preferably 2-butanone, 2-propanone and the like. The alkylation is conducted at a temperature from about 30° C. to the boiling point of the reaction mixture for about 30 minutes to ten hours.
A useful alternative method of esterification or alkylation comprises reacting the acidic hydroxy compound of formula I with an excess of a diazoalkane, for instance diazomethane, diazoethane and the like, in an inert solvent, e.g. diethyl ether or methanol.
The compound of formula I in which at least one of R 1 , R 2 , R 3 , R 4 , R 5 and R 6 is lower alkoxy, chlorine, bromine or iodine can be reacted with sodium sulfhydrate in an inert solvent, preferably a lower alkanol (i.e. methanol, ethanol and the like) to obtain the corresponding compound of formula I in which the corresponding R 1 , R 2 , R 3 , R 4 , R 5 and R 6 is mercapto. This reaction is preferably carried out at a temperature of from about -70° C. to about 30° C. for about one to ten hours.
The following examples illustrate further this invention.
EXAMPLE 1
[(2-Oxo-3,5,7-cycloheptairien-1-yl)amino]oxo-acetic Acid Ethyl Ester: I (R 1 ═NH-CO-COOC 2 11 5 and R 2 , R 3 , R 4 , R 5 and R 6 ═11)
A solution of ethyl oxalyl chloride (0.30 g) in pyridine (15ml) is added to a solution of 2-amino-2,4,6-cycloheptatrien-1-one [0.242 g, described by T. Nozoe et al., Proc. Japan Acad. 27, 556-560 (1951), CA 46 7559 g] in pyridine (0.5 ml). The mixture is heated until a solution forms and the solution is stirred at room temperature for 45 minutes. Water is added and collection of the precipitate gives the title compound, mp 114° C.
In the same manner but replacing 2-amino-2,4,6-cycloheptatrien-1-one with an equivalent amount of 2-methylamino-2,4,6-cycloheptatrien-1-one [described by N. Soma et al., Chem. Pharm. Bull., 13, 457-64 (1965)], [N-(2-oxo-3,5,7 -cycloheptatrien-1-yl)-N-methylamino]oxoacetic acid ethyl ester, mp 70°-71° C., is obtained.
In the same manner but replacing ethyl oxalyl chloride with an equivalent amount of methyl or propyl oxalyl chloride, the methyl and propyl esters of the title compound are obtained.
EXAMPLE 2
[(3-Bromo-2-oxo-3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic Acid Ethyl Ester I (R 1 ═NH-CO-COOC 2 H 5 ; R 2 , R 3 , R 4 and R 5 ═11 and R 6 ═Br)
A solution of 7-bromo-2-methoxy-2,4,6-cycloheptatrien-1-one [1.0 g, described by T. Nozol et al., Proc. Japan Acad., 27, 556-60 (1951), (CA 46, 7560c)] in methanol (30 ml) is cooled to -20° C. and saturated with gaseous ammonia. The reaction mixture is heated in a pressure bottle at 80° C. for four hours and cooled to -70° C. The bottle is opened and the solvent is removed under reduced pressure. The residue is boiled with ethyl acetate and the ethyl acetate extract is evaporated to give 2-amino-7-bromo-2,4,6-cycloheptatrien-1-one.
A solution of the latter compound (0.800 g) in pyridine (10 ml) is cooled to 0° C. and ethyl oxalyl chloride (0.544 g) is added dropwise. The mixture is stirred at 0° C. for one hour and at room temperature for two hours. The solvent is removed under reduced pressure and the residue is crystallized from methanol-acetone to give the title compound, mp 161°-163° C.
In the same manner but replacing 7-bromo-2-methoxy-2,4,6-cycloheptatrien-1-one with an equivalent amount of 5-chloro-2-methoxy-2,4,6-cycloheptatrien-1-one (described by T. Sato, Nippon Kagaku Zasshi, 80, 1171-4 (1959), (CA 55, 4389c), [(5-chloro-2-oxo-3,5,7-cycloheptatrien-1-yl)-amino]oxo-acetic acid ethyl ester, mp 178°-179° C., is obtained.
In the same manner but replacing ethyl oxalyl chloride with an equivalent amount of methyl or propyl oxalyl cloride, the methyl and propyl esters of the title compound are obtained.
EXAMPLE 3
[(3-Phenoxy-2-oxo-3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic Acid Ethyl Ester; I (R 1 ═NH-CO-COOC 2 H 5 ; R 2 , R 3 , R 4 and R 5 ═H and R 6 ═OC 6 H 5 )
(a) A mixture of 2-hydroxy-3-phenoxy-2,4,6-cycloheptatriene-1-one (13.0 g), described by Y. Kitahara, Sci. Repts. Tohoku Univ. First Ser., 39, 265-74 (1956), (CA 51, 12874f) potassium carbonate (28.9 g), dimethylsulfate (26.5 g) and methyl ethyl ketone (680 ml) is healed at reflux for two hours. The hot mixture is filtered and the filtrate is evaporated under reduced pressure. The residue is subjected to chromatography on silica gel using ether. The appropriate fractions of the eluate are combined and evaporated to give 2-methoxy-3-phenoxy-2,4,6-cycloheptatrien-1-one and 2-methoxy-7-phenoxy-2,4,6-cycloheptatrien-1-one.
(b) A solution of 2-methoxy-7-phenoxy-2,4,6-cycloheptatrien-1-one (2.0 g, described above) in methanol (30 ml) is cooled to -25° C. and saturated with gaseous ammonia. The mixture is heated in a pressure bottle at 80° C. for four hours and cooled to -70° C. The bottle is opened and the solvent is removed under reduced pressure. The residue is crystallized from ethyl acetate to give 2-amino-7-phenoxy-2,4,6-cycloheptatrien-1-one.
In the same manner but replacing 2-methoxy-7-phenoxy-2,4,6-cycloheptatrien-1-one with an equivalent amount of 2-methoxy-3-phenoxy-2,4,6-cycloheptatrien-1-one [described above in (a)], 2-amino-3-phenoxy-2,4,6-cycloheptatrien-1-one is obtained.
(c) A solution of 2-amino-7-phenoxy-2,4,6-cycloheptatrien-1-one [1.38 g, described above in (b)] in pyridine (50 ml) is cooled to 0° C. and ethyl oxalyl chloride (0.980 g) is added dropwise. The mixture is stirred at 0° C. for one hour and at room temperature for two hours. Most of the solvent is removed under reduced pressure and water (200 ml) is added. The precipitate is collected and crystallized from ethyl acetate to give the title compound, mp 145°-145.5° C.
In the same manner but replacing ethyl oxalyl chloride with an equivalent amount of methyl or propyl oxalyl chloride, the methyl and propyl esters of the title compound are obtained.
In the same manner but replacing 2-amino-7-phenoxy-2,4,6-cycloheptatrien-1-one with an equivalent amount of 2-amino-3-phenoxy-2,4,6-cycloheptatrien-1-one (described above in (b))], [(7-phenoxy-2-oxo-3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic acid ethyl ester, mp 121°-122° C., is obtained.
EXAMPLE 4
[(5-Hydroxy-4-oxo-2,5,7-cycloheptatrien-1-yl)amino]oxo-acetic Acid Ethyl Ester: I (R 1 ═OH, R 2 , R 3 , R 5 and R 6 =H and R 4 ═NH-CO-COOC 2 H 5 )
Ethyl oxalyl chloride (1.36 g) is added dropwise to a solution of 0° C. of 5-amino-2-hydroxy-2,4,6-cycloheptatrien-1-one [0.680 g, described by T. Nozoe et al., Sci. Repts. Tohoku Univ. 1, 35. 274- 82 (1952)] in pyridine (15 ml). After 30 min. the reaction mixture is allowed to reach room temperature. The solvent is removed under reduced pressure and the residue is dissolved in methylene chloride. The solution is washed with water, dried, evaporated and the residue is crystallized from ethyl acetate to give the title compound, mp 186°-187° C.
In the same manner but replacing ethyl oxalyl chloride with an equivalent amount of ethyl oxalyl bromide, the title compound is obtained.
In the same manner but replacing ethyl oxalyl chloride with an equivalent amount of methyl oxalyl chloride or propyl oxalyl bromide [(5-hydroxy-4-oxo-2,5,7-cycloheptatrien-1-yl)amino]oxo-acetic acid methyl ester and [(5-hydroxy-4-oxo-2,5,7-cycloheptatrien-1-yl)amino]oxo-acetic acid propyl ester are obtained respectively.
EXAMPLE 5
[(3-Hydroxy-2-oxo-3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic Acid Ethyl Ester; I (R 1 ═NH-CO-COOC 2 H 5 ; R 2 , R 3 , R 4 and R 5 ═H and R 6 ═OH
The hot solutions of 3-bromo-2-hydroxy-2,4,6-cycloheptatriene-1-one (30.0 g) in methanol (2000 ml) and cupric acetate (18.0 g) in methanol (2000 ml) are mixed and the precipitate is collected to give 3-bromo-2-hydroxy-2,4,6-cycloheptatrien-1-one copper complex.
A mixture of the latter compound (11.65 g), potassium p-toluenesulfonamide (15.7 g) and pyridine (150 ml) is heated at reflux for 16 hours. The pyridine is evaporated under reduced pressure and chloroform is added to the residue. The precipitate is collected and washed with chloroform. The precipitate is suspended in chloroform and 2N sulfuric acid (40 ml) followed by the addition of hydrogen sulfide gas until the copper complex is decomposed. The precipitate is removed by filtration and the organic phase of the filtrate is separated. The organic phase is dried over sodium sulfate and evaporated. The residue is mixed with methanol and the precipitate is collected to obtain 2-hydroxy-3-[[(4-methylphenyl)sulfonyl]amino]-2,4,6-cycloheptatrien-1-one, mp 177°-179° C.
A solution of the latter compound (5.0 g) in conc. sulfuric acid (25 ml) is stirred at room temperature for 16 hours. The solution is poured on ice, neutralized with sodium carbonate and extracted with chloroform. The solvent is removed by evaporation to give a residue of 3-amino-2-hydroxy-2,4,6-cycloheptatrien-1-one [the latter compound is described in Sci. Repts. Tohoku Univ. First Ser., 69, 83- 91 (1956)].
To a solution of the latter compound (1.19 g) and triethylamine (1.1 g) in methylene chloride (25 ml) at room temperature, ethyl oxalyl chloride (1.27 g) in methylene chloride (5 ml) is added dropwise. The mixture is stirred for four hours and washed with water. The organic phase is dried over sodium sulfate and evaporated. The residue crystallized from ethyl acetate to give the title compound, mp 158°-159° C.
In the same manner but replacing ethyl oxalyl chloride with an equivalent amount of methyl or propyl oxalyl chloride, the methyl and propyl esters of the title compound are obtained.
EXAMPLE 6
2,2'[(2-Oxo-3,5,7-cycloheptatrien-1,5-diyl)diimino]bis[2-oxo-acetic acid] Diethyl Ester; I (R 1 and R 4 ═NH-CO-COOC 2 H 5 and R 2 ,R 3 ,R 5 and R 4
Conc. ammonium hydroxide solution (50 ml) is added dropwise to a suspension of 2-hydroxy-5-nitroso-2,4,6-cycloheptatrien-1-one [10 g, described by T. Nozoe et al., Sci. Repts. Tohoku Univ., 35, 274- 82 (1952), (CA 47 3291a)] collected and washed with water then acetone to give 2-amino-5-nitroso-2,4,6-cycloheptatrien-1-one.
A mixture of the latter compound (5.0 g) and 5% palladium on charcoal (1.5 g) in ethanol (2000 ml) is stirred rapidly under an atmosphere of hydrogen for 12 minutes (hydrogen absorbed is 1600 ml). The mixture is filtered and the filtrate is evaporated to give 2,5-diamino-2,4,6-cycloheptatrien-1-one.
The latter compound is dissolved in pyridine (150 ml), cooled to 0° C. and ethyl oxalyl chloride (9.55 g) is added dropwise. The reaction mixture is warmed to room temperature and stirred for two hours. Half of the pyridine is evaporated under reduced pressure and the residue is added to water (400 ml). The precipitate is collected, crystallized from ethyl acetate and subjected to chromatography on silica gel using ethyl acetate for elution. The eluates are evaporated and the residue is crystallized from ethyl acetate to give the title compound, mp 217°-218° C.
In the same manner but replacing ethyl oxalyl chloride with an equivalent amount of methyl or propyl oxalyl chloride, the methyl and propyl esters of the title compound are obtained.
EXAMPLE 7
[(6-Methoxy-2-oxo-3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic Acid Ethyl Ester; I (R 1 ═ NH-CO-COOC 2 H 5 ; R 2 , R 4 , R 5 and R 6 ═H and R 3 ═OCH 3 )
(a) A solution of 3-bromo-2-hydroxy-2,4,6-cycloheptatrien-1-one [27.5 g, described by T. Toda et al., Nippon Kagaku Zasshi, 88, 1234-5 (1967), (CA 68 101342)] and sodium methoxide (prepared from 12.6 g of sodium in methanol followed by evaporation of the methanol) in dimethyl sulfoxide (300 ml) is heated at 80° C. for one hour. The solution is cooled poured on ice, acidified with 2N sulfuric acid and extracted with ethyl acetate. The organic extract is washed with brine, dried over sodium sulfate and evaporated. The residue is crystallized from ethyl acetate-hexane to give 2-hydroxy-3-methoxy-2,4,6-cycloheptatrien-1-one. Evaporation of the mother liquors gives 2-hydroxy-4-methoxy-2,4,6-cycloheptatrien-1-one.
(b) A mixture of 2-hydroxy-4-methoxy-2,4,6-cycloheptatrien-1-one (described above, 13 g), potassium carbonate (23.6 g), dimethyl sulfate (21.6 g) and 2-butanone (130 ml) is heated at reflux for 3 hours. The mixture is filtered and the filtrate is evaporated. The residue is subjected to chromatography on silica gel using acetone-ethyl acetate (1:1) and evaporation of the eluates gives 2,4-dimethoxy-2,4,6-cycloheptatrien-1-one and 2,6-dimethoxy-2,4,6-cycloheptatrien-1-one.
In the same manner but replacing 2-hydroxy-4-methoxy-2,4,6-cycloheptatrien-1-one with an equivalent amount of 2-hydroxy-3-methoxy-2,4,6-cycloheptatrien-1-one [(described above in(a)], 2,3-dimethoxy-2,4,6-cycloheptatrien-1-one and 2,7-dimethoxy-2,4,6-cycloheptatrien-1-one are obtained.
(c) A solution of 2,4-dimethoxy-2,4,6-cycloheptatrien-1-one [described above in(b),2.4 g] in methanol (70 ml) is cooled to -25° C. and saturated with ammonia gas. The solution is heated in a pressure bottle at 80° C. for 4 hours and cooled to -70° C. The pressure bottle is opened and the solvent is evaporated to give 2-amino-4-methoxy-2,4,6-cycloheptatrien-1-one.
In the same manner replacing 2,4-dimethoxy-2,4,6-cycloheptatrien-1-one with an equivalent amount of 2,6-dimethoxy-2,4,6-cycloheptatrien-1-one or 2,3-dimethoxy-2,4,6-cycloheptatrien-1-one, 2-amino-6-methoxy-2,4,6-cycloheptatrien-1-one and 2-amino-3-methoxy-2,4,6-cycloheptatrien-1-one are obtained, respectively. (d) A solution of ethyl oxalyl chloride (2.16 g) in methylene chloride (25 ml) is added dropwise to a solution of 2-amino-4-methoxy-2,4,6-cycloheptatrien-1-one [described above in (c), 2.9 g] and triethylamine (1.84 g) in methylene chloride (50 ml). The mixture is stirred at room temperature for 3 hours, washed with water, dried over sodium sulfate and evaporated. The residue is subjected to chromatography on silica gel using ethyl acetate-hexane (2:3). The eluates are evaporated to give the title compound, mp 132°-134° C.
In the same manner but replacing ethyl oxalyl chloride with an equivalent amount of methyl or propyl oxalyl chloride, the methyl and propyl esters of the title compound are obtained.
In the same manner but replacing 2-amino-4-methoxy-2,4,6-cycloheptatrien-1-one with an equivalent amount of 2-amino-6-methoxy-2,4,6-cyclopheptatrien-1-one or 2-amino-3-methoxy-2,4,6-cycloheptatrien-1-one, [(4-methoxy-2-oxo-3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic acid ethyl ester, mp 157°-158° C., and [(7-methoxy-2-oxo-3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic acid ethyl ester are obtained, respectively.
In the same manner but replacing dimethyl sulfate with an equivalent amount of diethyl sulfate, [(6-ethoxy-2-oxo-3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic acid ethyl ester is obtained.
EXAMPLE 8
[[7-Oxo-4-[(2-carboxyphenyl)thio]-1,3,5-cycloheptatrien-1-yl]amino]oxo-acetic acid Ethyl Ester; I (R 1 ═NH-CO-COOC 2 H 5 ; R 2 , R 3 , R 5 and R 6 ═H and R 4 ═2-carboxyphenylthio)
A solution of 5-[(2-carboxyphenyl)thio]-2-methoxy-2,4,6-cycloheptatrien-1-one (1.0 g, prepared from 5-chloro-2-methoxy-2,4,6-cycloheptatrien-1-one and 2-mercaptobenzoic acid) in methanol (30 ml) at -25° C. is saturated with ammonia gas. The solution is heated in a pressure bottle at 80° C. for 8 hours and cooled to -70° C. The bottle is opened and the solvent is evaporated to give 2-amino-5-[(2-carboxyphenyl)thio]-2,4,6-cycloheptatrien-1-one.
A solution of ethyl oxalyl chloride (1.0 g) in methylene chloride (10 ml) is added dropwise to a suspension of 2-amino-5-[(2-carboxyphenyl)thio]-2,4,6-cycloheptatrien-1-one (1.0 g) and triethylamine (0.74 g) in methylene chloride (30 ml). The mixture is stirred at room temperature for 30 minutes, washed with water, dried over sodium sulfate and evaporated. The residue is crystallized from ethyl acetate to give the title compound, mp 225-228° C.
In the same manner but replacing 2-amino-5-[(2-carboxyphenyl)thio]2,4,6-cycloheptatrien-1-one with an equivalent of 5-amino-2-[(2-carboxyphenyl)thio]-7-methyl-2,4,6-cycloheptatrien-1-one or 2-methylamino-6-[(2-carboxyphenyl)thio]-4-phenyl-2,4,6-cycloheptatrien-1-one, [[5-oxo-4-[(2-carboxyphenyl)thio]-6-methyl-1,3,6-cycloheptatrien-1-yl]-amino]oxo-acetic acid ethyl ester and [N-[7-oxo-5-[(2-carboxyphenyl)thio]-3-phenyl- 1,3,5-cycloheptatrien-1-yl]-N-methylamino]oxo-acetic acid ethyl ester are obtained, respectively.
EXAMPLE 9
[[3-[N-[(4-Methylphenyl)sulfonyl[ -N-Methylamino]-2-oxo-3,5,7-cycloheptatrien-1-yl]amino]oxo-acetic Acid Ethyl Ester; I [R 1 ═NH-CO-COOC 2 H 5 ; R 2 , R 3 , R 4 and R 5 ═H annd R 6 ═[N-(4-methylphenyl)sulfonyl]-N-methylamino]
(a) A mixture of 2-hydroxy-3-[N-[(4-methylphenyl)sulfonyl]-amino]-2,4,6-cycloheptatrien-1-one (14.5 g), potassium carbonate (12.5 g), dimethyl sulfate (12.5 g) and 2-butanone (145 ml) is heated at reflux for one hour. The mixture is filtered and the precipitate is washed with water and suspended in ethyl acetate. Hydrochloric acid (10%) is added until the solution is acidic. The organic phase is collected and dried over sodium sulfate. Evaporation of the solvent and crystallization of the residue from ethyl acetate-hexane gives 2-methoxy-7-[N-[(4-methylphenyl)sulfonyl]amino]-2,4,6-cycloheptatrien-1-one, mp 163°-164° C. The above filtrate is evaporated annd the residue is subjected to chromatography on silica gel using ethyl acetate-hexane (3:1). Evaporation of the eluates are crystallization of the residue from ethyl acetate gives 2-methoxy-3-[N-[(4-methylphenyl)sulfonyl]-N-methylamino]-2,4,6-cycloheptatrien-1-one, mp 101°-102° C. and 2-methoxy-7-[N-[(4-methylphenyl)sulfonyl]-N-methylamino]-2,4,6-cycloheptatrien-1-one, mp 94.5° C.
(b) A solution at -25° C. of 2-methoxy-7-[N-[(4-methylphenyl)-sulfonyl]-N-methylamino]-2,4,6-cycloheptatrien-1-one (described above, 4.0 g) in methanol (40 ml) is saturated with ammonia gas and heated in a pressure bottle at 80° C. for 4 hours. The solution is cooled to -70° C., the bottle is opened and the solvent is evaporated to yield 2-amino-7-[N-[(4-methylphenyl)sulfonyl]-N-methylamino]-2,4,6-cycloheptatrien-1-one, mp 221°-222° C.
In the same manner but replacing 2-methoxy-7-[N-[(4-methylphenyl)sulfonyl]-N-methylamino]-2,4,6-cycloheptatrien-1-one with an equivalent amount of 2-methoxy-7-[N-[(4-methylphenyl)sulfonyl]-amino]-2,4,6-cycloheptatrien-1-one or 2-methoxy-3-[N-[(4-methylphenyl)sulfonyl]-N-methylamino]-2,4,6-cycloheptatrien-1-one, 2-amino-7-[N-[(4-methylphenyl)sulfonyl]amino]-2,4,6-cycloheptatrien-1-one and 2-amino3-[N-[(4-methylphenyl)sulfonyl]-N-methylamino]-2,4,6-cycloheptatrien- 1-one are obtained respectively.
(c) A solution of ethyl oxalyl chloride (0.475 g) in methylene chloride (10 ml) is added dropwise to a solution of 2-amino-7-[N-[(4-methylphenyl)sulfonyl]-N-methylamino]-2,4,6-cycloheptatriene-1-one (described above, 0.87 g) and triethylamine (0.354 g) in methylene chloride (10 ml). The solution is stirred at room temperature for 2 hours, washed with water, dried over sodium sulfate and evaporated. The residue is crystallized from ethyl acetate-hexane to give the title compound, mp 148.5°-150° C.
In the same manner but replacing ethyl oxalyl chloride with an equivalent amount of methyl or propyl oxalyl chloride, the methyl and propyl esters of the title compound are obtained.
In the same manner but replacing 2-amino-7-[N-[(4-methylphenyl)sulfonyl]-N-methylamino]-2,4,6-cycloheptatrien-1-one with an equivalent amount of 2-amino-7-[N-[(4-methylphenyl)sulfonyl]amino]-2,4,6-cycloheptatrien-1-one or 2-amino-3-[N-[(4-methylphenyl)sulfonyl] -N-methylamino]-2,4,6-cycloheptatrien-1-one, [[3-[ N-[(4-methylphenyl)sulfonyl]amino]-2-oxo-3,5,7-cycloheptatrien-1-yl]amino]oxo-acetic acid ethyl ester and [[7-[N-[(4-methylphenyl)sulfonyl]-N-methylamino]-2-ox0-3,5,7-cycloheptatrien-1-yl]amino]oxo-acetic acid ethyl ester are obtained respectively.
In the same manner but replacing dimethyl sulfate with an equivalent amount of diethyl sulfate, the title compound is obtained.
EXAMPLE 10
[(3-Methylamino-2-oxo-3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic Acid Ethyl Ester; I (R 1 ═NH-CO-COOC 2 H 5 ; R 2 , R 3 , R 4 and R 5 ═H and R 6 ═NHCH 3 )
A solution of 2-amino-7-[N-[(4-methylphenyl)sulfonyl]-N-methylamino]-2,4,6-cycloheptatrien-1-one [described in Example 9 (b). 2.53 g] in conc. sulfuric acid (25 ml) is heated at 75° C. for 1 hour and added to ice. The ice-mixture is neutralized with sat. sodium carbonate solution and extracted with chloroform. The organic extract is dried over sodium sulfate and evaporated to give 2-amino-7-methylamino-2,4,6-cyclopheptatrien-1-one.
A solution of ethyl oxalyl chloride (2.46 g) in methylene chloride (10 ml) is added dropwise to a solution of 2-amino-7-methylamino-2,4,6-cycloheptatrien-1-one (1.32 g) and triethylamine (1.95 g) in methylene chloride (15 ml). The mixture is heated at reflux for 3 hours, washed with water, dried over sodium sulfate and evaporated. The residue is subjected to chromatography on silica gel using acetone-hexane (3:7) and the eluates are evaporated to give the title compound, mp 178°-181° C.
In the same manner but replacing ethyl oxalyl chloride with an equivalent amount of methyl or propyl oxalyl chloride, the methyl and propyl esters of the title compound are obtained.
In the same manner but replacing 2-amino-7-[N-[(4methylphenyl)sulfonyl]-N-methylamino]-2,4,6-cycloheptatrien-1-one with an equivalent amount of 2-methoxy-7-[N-[(4-methylphenyl)sulfonyl]amino]- 2,4,6-cycloheptatrien-1-one [described in Example (9 )], [(3-methoxy-2-oxo-3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic acid ethyl ester, mp 164°-167° C., is obtained.
By following a procedure selected from Examples 1 to 10 using the appropriate starting material of formula II and the appropriate compound of formula III in which R 10 is lower alkyl, other compounds of formula I in which at least one of R 1 and R 4 is NR 9 COCOOR 10 wherein R 9 is as defined herein and R 10 is lower alkyl are obtained. Examples of the latter compounds of formula 1 are listed as products in Table 1 together with the appropriate starting material of formula II used for the preparation of the compound of formula I.
TABLE 1__________________________________________________________________________ Product: [(prefix listed below)-cycloheptatrien-l-yl)amino]-Starting Material of Formula II oxo-acetic acid (suffix listed below)]Ex. R.sup.12 R.sup.13 R.sup.14 R.sup.15 R.sup.16 R.sup.17 Prefix/Suffix__________________________________________________________________________11 H H H NH.sub.2 Br CH.sub.3 [(2-bromo-3-methyl-4-oxo-2,5,7 // ethyl ester12 NHCH.sub.3 H CH.sub.3 H C.sub.6 H.sub.5 H [N-methyl-N-(6-methyl-2-oxo-4-phenyl-3,5 ,7 // ethyl ester13 NH.sub.2 H H OC.sub.2 H.sub.5 H I [(5-ethoxy-3-iodo-2-oxo-3,5,7 // methyl ester14 NH.sub.2 H H NHCH.sub.3 CH.sub.3 H [[5-[N-(2-ethoxy-1,2-dioxoethyl)methylam ino]-4-methyl-15 H C.sub.3 H.sub.7 H NH.sub.2 H CF.sub.3 [(2-oxo-7-propyl-3-trifluromethyl-3,5,7 // methyl ester16 NH.sub.2 C.sub.5 H.sub.11 H H H OC.sub.3 H.sub.7 [(2-oxo-7-pentyl-3-propoxy-3,5,7 // propyl ester17 NHC.sub.3 H.sub.7 H OH F H H [N-butyl-N-(5-fluoro-6-hydroxy-2-oxo-3,5 ,7 // propyl ester18 NHC.sub.3 H.sub.7 H H NH.sub.2 H OC.sub.6 H.sub.5 [[5-[N-(2-ethoxy-1,2-dioxoy-1,2-dioxoeth yl)propylamino]-4-oxo-3- phenoxy-2,5,7 // ethyl ester19 OC.sub.2 H.sub.5 H C.sub.4 H.sub.9 NHC.sub.2 H.sub.5 H H [N-ethyl-N-(7-butyl-5-ethoxy-4-oxo-2,5,7 // methyl ester20 H OCH.sub.3 H NH.sub.2 H OH [(3-hydroxy-6-methoxy-4-oxo-2,5,7 // ethyl ester21 H SH H NH.sub.2 C.sub.2 H.sub.5 H [(2-ethyl-6-mercapto-4-oxo-2,5,7 // propyl ester22 NH.sub.2 H Cl H OH H [(6-chloro-4-hydrpxy-2-oxo-3,5,7 // ethyl ester23 NHC.sub.4 H.sub.9 H OC.sub.6 H.sub.5 H H SH [N-butyl-N-(3-mercapto-2-oxo-6-phenoxy-3 ,5,7 // methyl ester24 CF.sub.3 Br H NH.sub.2 H H [(6-bromo-4-oxo-5-trifluoromethyl-2,5,7 // ethyl ester25 NH.sub.2 H H N(CH.sub.3).sub.2 Cl H [(4-chloro-5-dimethylamino-2-oxo-3,5,7 // ethyl ester26 NH.sub.2 H OC.sub.2 H.sub.5 H H N(C.sub.3 H.sub.7).sub.2 [(6-ethoxy-3-dipropylamino-2-oxo-3,5,7 // methyl ester27 N(C.sub.2 H.sub.5).sub.2 CH.sub.3 OH NH.sub.2 H H [(5-diethylamino-7-hydroxy-6-methyl-4-ox o-2,5,7 // ethyl ester28 NH.sub.2 SH H H N(CH.sub.3) (C.sub. 2 H.sub.5) H [[4-(N-ethyl-N-methylamino)-7-mercapto-2 -oxo-3,5,7 //propyl ester__________________________________________________________________________
EXAMPLE 29
[(5-Methoxy-4-oxo-2,5,7-cyclopheptatrien-1-yl)amino]oxo-acetic Acid Methyl Ester; I (R 1 =OCH 3 ; R 2 , R 3 , R 5 and R 6 H and R 4 =NH-CO-C00CH 3 )
[(5-Hydroxy-4-oxo-2,5,7-cyclopheptatrien-1-yl)amino]oxoacetic acid ethyl ester (4.1 g, described in Example 4) is dissolved in boiling methanol (500 ml) and the mixture is cooled to room temperature and reacted with a solution of diazomethane in ether (ca. 351 ml). The reaction mixture is stirred for one hour until all the solid is reacted with diazomethane. The solvent is removed under reduced pressure and the residue is crystallized from methanol to give the title compound, mp 198°-200° C.
In the same manner but replacing [(5-hydroxy-4-oxo-2,5,7-cycloheptatrien-1-yl)amino]oxo-acetic acid ethyl ester with an equivalent amount of [(3-hydroxy-2-oxo-3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic acid ethyl ester (described in Example 5), [(3-methoxy-2-oxo-3,5,7-cycloheptatriem-1-yl)amino]oxo-acetic acid methyl ester is obtained.
EXAMPLE 30
[(2-Oxo-3,5,7-cycloheptatrient-1-yl)amino]oxo-acetic Acid; I (R 1 =NH-CO-C00H and R 2 , R 3 , R 4 , R 5 and R 6 =H)
A solution of potassium acetate (0.98 g) in water (5 ml) is added to a suspension of [(2-oxo-3,5,7-cyclopheptatrien-1-yl)amino]oxo-acetic acid ethyl ester (2.21 g, described in Exaple 1) in water (15 ml) and the resulting mixture is heated at 100° C. for five hours. The mixture is cooled, diluted with water, charcoalized and filtered. The filtrate is acidified with 10% hydrochloric acid and the precipitate is collected to give the title compound, mp 193°-194° C.
In the same manner but replacing potassium acetate with an equivalent amount of sodium bicarbonate or potassium carbonate, the title compound is obtained.
In the same manner but replacing the starting material [(2-oxo-3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic acid ethyl ester with other esters of formula 1, other acids of formula 1 are obtained. For example, replacing the starting material with the title compound of Examples 2,3,5,6,7,8,14 and 23, the following acids of formula 1 are obtained respectively: [(3-bromo-2-oxo-3,5,7cycloheptatrien-1-yl)amino]oxo-acetic acid, [(3-phenoxy-2-oxo-3,5,7cycloheptatrien-1-yl)amino]oxo-acetic acid, [(3-hydroxy-2-oxo-3,5,7cycloheptatrien-1-yl)amino]oxo-acetic acid, 2,2'[(2-oxo-3,5,7cyclohpetatrien-1,5-diyl)diimino]bis[2-oxo-acetic acid], [(6-methoxy2-oxo-3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic acid, [(3-methylamino2-oxo-3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic acid. [[5-[N-(carboxycarbonyl)-N-methylamino]-4-methyl-2-oxo-3,5,7-cyclopheptatrien-1-yl]amino]oxoacetic acid and [N-(3-mercapto-2-oxo-6-phenoxy-3,5,7-cycloheptatrien-1-yl)-N-butylamino]oxo-acetic acid.
A solution of the title compound (0.57 g) and 2-amino-2-hydroxymethyl-1,3-propanediol (0.363 g) in water (1 ml) is stirred at 25° C. for 75 min and lyopholized. The residue is crystallized from methanol-acetone to obtain crystals of the 2-amino-2-hydroxymethyl-1,3-propanediol salt of the title compound, mp 148°-152° C.
A solution at 50°-60° C. of the title compound (0.386 g) in methanol (35 ml) is added to a solution of potassium hexanonate (0.92 g) in methanol-diethyl ether (1:1, 7 ml). The resulting solution is stirred at room temperature for 30 min and cooled to 0° C. The precipitate is collected, washed with water and crystallized from acetone-water to obtain crystals of the potassium salt of the title compound, mp 245°-265° C.
EXAMPLE 31
[(2-Oxo-3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic Acid Pentyl Ester: I (R 1 =NH-CO-COOC 5 H 11 and R 2 , R 3 , R 4 , R 5 and R 6 =H
A solution of [(2-oxo-3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic acid (1.54 g, described in Example 30) and potassium carbonate (0.82 g) in dimethylsulfoxide (8 ml) is stirred at room temperature for 15 minutes. A solution of 5-bromopentane (1.52 ml) in dimethylsulfoxide (8 ml) is added and the resulting mixture is stirred at 80° C. for 40 minutes. The mixture is cooled to room temperature and poured over ice. The mixture is stirred for ten minutes and the precipitate is collected by filtration. The precipitate is dissolved in ether, treated with charcoal and crystallized by the addition of hexane to give the title compound, mp 87°-89° C.
In the same manner but replacing the alkyl halide, 5-bromopentane, with an equivalent amount of 2-bromopropane or 2-bromo-2-methylpropane, [(2-oxo-3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic acid 1-methylethyl ester, mp 91°-93° C. and [(2-oxo-3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic acid, 1,1-dimethylethyl ester, mp 76°-78° C., are obtained respectively.
In the same manner but replacing the starting material, [(2-oxo-3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic acid, with other acids of formula I and using an appropriate alkyl halide other esters of formula I are obtained. For example, replacing the starting material with an acid described in Example 30, the following esters of formula I are obtained.
[(3-bromo-2-oxo-3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic acid 2-methylpropyl ester, [(3-phenoxy-2-oxo-3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic acid hexyl ester, 2,2'-[(2-oxo-3,5,7-cycloheptatrien-1,5-diyl)diimino]bis[2-oxo-acetic acid]dipropyl ester, [(6-methoxy-2-oxo-3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic acid 1,1-dimethylethyl ester and [[5-[N-2-butoxy-1,2-dioxoethyl)methyl amino]-4-methyl-2-oxo-3,5,7-cyclopheptatrien-1-yl]amino]oxo-acetic acid butyl ester.
EXAMPLE 32
[(2-Oxo-3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic Acid Hydrazide; I (R 1 =NH-CO-CONHNH 2 and R 2 , R 3 , R 4 , R 5 and R 6 ═H)
A mixture of [(2-oxo-3,4,7-cycloheptatrien-1-yl)amino]oxo-acetic acid ethyl ester (1.2 g, described in Example 1) and anhydrous hydrazine in anhydrous ethanol (25 ml) is stirred at 25° C. for 5 hr. The precipitate is collected on a filter and crystallized from methanol to give crystals of the title compound, mp 193° C.
In the same manner but replacing [(2-oxo-3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic acid ethyl ester with an equivalent amount of [N-(2-oxo-3,5,7-cycloheptatrien-1-yl)-N-methylamino]oxo-acetic acid ethyl ester (described in Example 1), [(3-bromo-2-oxo-3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic acid ethyl ester (described in Example 2), [(5-hydroxy-4-oxo-2,5,7-cycloheptatrien1-yl)amino]oxo-acetic acid ethyl ester (described in Example 4), 2,2'[(2-oxo-3,5,7-cycloheptatrien-1,5-diyl)diimino]bis[2-oxo-acetic acid] diethyl ester (described in Example 6) or [(3-methylamono-2-oxo3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic acid ethyl ester (described in Example 10), the following compounds of formula I are obtained, respectively: [N-(2-oxo-3,5,7-cycloheptatrien-1-yl)-N-methylamino]-2-oxoacetic acid hydrazide, [(3-bromo-2-oxo-3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic acid hydrazide, [(5-hydroxy-4-oxo-2,5,7-cycloheptatrien-1-yl)amino]oxo-acetic acid hydrazide, 2,2'[(2-oxo-3,5,7-cycloheptatrien-1,5-diyl)diimino]bis[2-oxo-acetic acid] dihydrazide and [(3-methylamino-2 -oxo-3,5,7-cycloheptatrien-1-yl)-amino]oxo-acetic acid hydrazide.
EXAMPLE 33
2 [2-(2-Oxo-3,5,7-cycloheptatrien-1-yl)amino]-1,2-dioxoethoxy]acetic Acid Ethyl Ester; I (R 1 =NHCOCOOCH 2 COOC 2 H 5 and R 2 , R 3 , R 4 , R 5 and R 6 =H)
A solution of bromo ethyl acetate (1.6 ml) in dimethyl sulfoxide (8 ml) is added to a solution of [(2-oxo-3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic acid (1.93 g, described in Example 30) and potassium carbonate (1.03 g) in dimethyl sulfoxide (8 ml). The solution is stirred at 70° C. for 1.5 hr, cooled to 0° C. and a mixture of ice and water is added. The precipitate is collected and crystallized from chloroform-hexane to obtain crystals of the title compound, mp 110°-112° C.
In the same manner but replacing bromo ethyl acetate with an equivalent amount of bromo t-butyl acetate, 3-chloro-propionic acid methyl ester or 5-iodo-pentanoic acid propyl ester, the following compounds of formula I are obtained, respectively, 2-[2-(2-oxo3,5,7-cycloheptatrien-1-yl)amino]-1,2-dioxo-ethoxy]acetic acid t-butyl ester, mp 264°-266° C., 2[2-(2-oxo-3,5,7-cycloheptatrien-1-yl)-amino]-1,2-dioxo-ethoxy]acetic acid propyl ester, and 2-[2-(2-oxo3,5,7-cycloheptatrien-1-yl)amino]-1,2-dioxo-ethoxy]acetic acid pentyl ester.
In the same manner using bromo ethyl acetate but replacing [(2-oxo-3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic acid with the following acids described in Example 30, [(3-bromo-2-oxo-3,5,7-cycloheptatrien-1-yl)-amino]oxo-acetic acid, [(3-phenoxy-2-oxo-3,5,7-cycloheptatrien-1-yl)-amino]oxo-acetic acid, 2,2'[(2-oxo-3,5,7-cycloheptatrien-1,5-diyl)diimino]bis[2-oxo-acetic acid] or [(6-methoxy-2-oxo-3,5,7-cycloheptatrien-1-yl)amino]oxo-acetic acid, the following compounds of formula I are obtained, respectively: 2-[2-[(3 -bromo-2-oxo-3,5,7-cycloheptatrien-1-yl)amino]-1,2-dioxo-ethoxy]-acetic acid ethyl ester, 2-[2-(3-phenoxy-2-oxo-3,5,7-cycloheptatrien1-yl)-amino]-1,2-dioxo-ethoxy]-acetic acid ethyl ester, 2,2'-[2,2'-[(2-oxo-3,5,7-cycloheptatrien-1,5-diyl)diimino]bis-(1,2-dioxo-ethoxy)-]diacetic acid diethyl ester, 2-[2-(6-methoxy-2-oxo-3,5,7-cycloheptatrien1-yl)-amino]-1,2-dioxo-ethoxy]acetic acid ethyl ester.
EXAMPLE 34
2-[2[-(2-Oxo-3,5,7-cycloheptatrien-1-yl)amino]-1,2-dioxo-ethoxy]acetic Acid; I (R 1 =NHCOCOOCH 2 COOH and R 2 , R 3 , R 4 , R 5 and R 6 =H)
A mixture of 2-[2-[2-(2-oxo-3,5,7-cycloheptatrien-1-yl)-amino]1,2-dioxo-ethoxy]acetic acid t-butyl ester(8.4 g, described in Example 33) and concentrated hydrochloric acid (90 ml) is stirred at -20° C. for 2 hr and ice is added. The precipitate is collected and dried to obtain a powder of the title compound, nmr (D 2 O) δ 4.7 (s, 2H) and 7.3 (m, 5H).
A solution of the latter compound (7.1 g) and potassium hexanoate (12.7 g) in dry tetrahydrofuran (30 ml) is heated at 80° C. for 2 hr and cooled. The precipitate is collected and crystallized from water-methanol to obtain crystals of the potassium salt of the title compound, mp. 257°-259° C. | Tropone derivatives characterized by having a derivative of oxamic acid at positions 2 and or 5 are disclosed. In addition, the tropone nucleus can be optionally further substituted. The foregoing compounds are useful for preventing or treating allergic conditions in a mammal. Methods for the preparation and use of said compounds are disclosed. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION(S)
[0001] This application claims the benefit of U.S. Provisional Patent Application Nos. 60/633,007 and 633,089 filed on Dec. 3, 2004, both of which are incorporated herein by reference.
TECHNICAL FIELD
[0002] The embodiments described below relate generally to wireless communication systems, and more particularly, relate to simultaneous demodulation and decoding of amplitude-modulated (AM) and frequency-modulated (FM) signals in a utility data collection system.
BACKGROUND
[0003] Historically meter readings of the consumption of utility resources such as water, gas, or electricity have been accomplished manually by human meter readers at customers premises. The relatively recent advances in this area include collection of data by telephone lines, radio transmission, walk-by, or drive-by reading systems using radio communications between the meters and meter reading devices. Although some of these methods require close physical proximity to the meters, they have become more desirable than the manual reading and recording of the consumption levels. Over the last few years, there has been a concerted effort to automate meter reading by installing fixed networks that allow data to flow from the meter to a host computer system without human intervention. These systems are referred to in the art as Automated Meter Reading (AMR) systems.
[0004] A mobile AMR system comprises an Encoder-Receiver-Transmitter (ERT), which is a meter interface device attached to the meter and either periodically or in response to a request transmits utility consumption data. Today, some ERTs transmit AM, while others transmit FM signals. In other fields, there are systems configured to receive both types of signals concurrently. For example in the automotive field, radio receivers possessing both AM and FM reception are common.
[0005] The Kaufman (U.S. Pat. No. 4,001,702), Funabashi (U.S. Pat. No. 4,070,628), von der Neyen (U.S. Pat. No. 4,304,004), Mason (U.S. Pat. No. 3,206,680), Peil (U.S. Pat. No. 3,665,507), Lundquist et al (U.S. Pat. No. 3,745,467), Ohsawa et al. (U.S. Pat. No. 3,919,645) and Denenberg (U.S. Pat. No. 3,971,988) patents are all radio receivers capable of receiving AM and FM signals; however, most automotive radio receivers, such as the ones of Funabashi, Mason, Peil, Lundquist et al, Ohsawa et al, and Denenberg receive AM and FM signals as alternatives and merely allow the user to select between the two signals. As such, two kinds of traditional receivers are required for demodulation and decoding of the two possible transmission types, which complicates the required hardware, entails extra cost, etc.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 illustrates the basic elements and processes of a mobile AMR system that may employ aspects of the invention.
[0007] FIG. 2 is a high level block diagram of elements of a dual-mode receiver in accordance with an embodiment of the invention.
[0008] FIG. 3A is a schematic diagram of a signal presented in a Cartesian coordinate system constructed by two basis functions φ 1 (t) and φ 2 (t).
[0009] FIG. 3B is a schematic diagram of a signal presented in a Polar coordinate system constructed by two basis functions φ 1 (t) and φ 2 (t).
[0010] FIG. 4 is a flow diagram of an example of steps involved in decoding an AM-FM AMR signal.
[0011] FIGS. 5 and 6 are two alternative embodiments to the receiver of FIG. 2 .
DETAILED DESCRIPTION
[0012] Various embodiments of the invention will now be described. The following description provides specific details for a thorough understanding and enabling description of these embodiments. One skilled in the art will understand, however, that the invention may be practiced without many of these details. Additionally, some well-known structures or functions may not be shown or described in detail, so as to avoid unnecessarily obscuring the relevant description of the various embodiments.
[0013] The terminology used in the description presented below is intended to be interpreted in its broadest reasonable manner, even though it is being used in conjunction with a detailed description of certain specific embodiments of the invention. Certain terms may even be emphasized below; however, any terminology intended to be interpreted in any restricted manner will be overtly and specifically defined as such in this Detailed Description section. In the following description, several specific details are presented to provide a thorough understanding of the embodiments of the invention. One skilled in the relevant art will recognize, however, that the invention can be practiced without one or more of the specific details, or in combination with or with other components, etc. In other instances, well-known implementations or operations are not shown or described in detail to avoid obscuring aspects of various embodiments of the invention. Even though different aspects of this invention are mostly presented in the context of utility data collection, they can be applied to any AM and FM receiving system, and the description of the invention is not intended to limit its applicability to any particular field of usage.
[0000] Suitable System
[0014] FIG. 1 illustrates the basic elements and processes of a mobile AMR system 100 . The mobile AMR system 100 consists of three basic components: an Encoder-Receiver-Transmitter (ERT) 106 , a Data Collection Unit (DCU) 110 , and AMR Software. The ERT 106 is a meter interface device attached to the meter, which either periodically transmits utility consumption data 108 (“bubble-up” ERTS), or receives a “wake up” polling signal or a request 104 for its meter information from a transceiver mounted in a passing vehicle 102 or carried by the meter reader. The ERT 106 , in response to a wake-up signal 104 , broadcasts the meter number, the meter reading, and other information to the DCU 110 , which is a mobile computer, for example, in the meter reading vehicle 102 . The DCU 110 collects the information from the ERTs 106 for subsequent uploading into the AMR Software system. The AMR Software interfaces with the main system 112 and updates the appropriate accounts of the billing system with the new meter readings.
[0000] Dual AM-FM Decoding
[0015] As described in detail below, the AMR system 100 provides for simultaneous demodulation and decoding of both amplitude-modulated (AM) and frequency-modulated (FM) signals by the Data Collection Unit (DCU) 110 . Demodulating and decoding both kinds of signals arise, for example, as a result of some endpoint Encoder-Receiver-Transmitters (ERTs) broadcasting utility data through AM signals, while newer ERT endpoints transmit meter readings via FM signals.
[0016] The need for demodulation and decoding of both kinds of signals also arises as a result of simultaneous transmission of both signals by a hybrid system which is configured to broadcast both AM and FM signals. As long as both transmission methods coexist and are in use, the DCU 110 can easily, efficiently, interchangeably or simultaneously decode signal types. The prior art has addressed this problem by merely employing separate AM and FM receivers.
[0017] The embodiments of this invention utilize the frequency spectrum of an arriving signal to identify its modulation type, to demodulate the data, and to direct the demodulated data to an appropriate path for decoding. For the purpose of demonstration, the examples presented in this application employ the output of an FFT (Fast Fourier Transform) process as the basis for identifying, demodulating and decoding an arriving signal. While not requiring traditional dedicated narrow-band FM receiver to decode FM data, the embodiments of this invention utilize an FFT engine to decode FM data in a channelized radio.
[0018] FIG. 2 is a high level block diagram of elements of a dual-mode receiver for DCU 110 in accordance with an embodiment of the invention. In this embodiment, a sampled and quantized RF (Radio Frequency) signal 210 passes through a Fast Fourier Transform (FFT) engine 212 for deciphering its frequency spectrum 214 . The incoming signal is modulated on a particular carrier and includes a preamble followed by a data packet. Two different preambles may be used to distinguish between AM and FM signals, wherein a preamble is a data pattern, unique to each type of transmission, sent on the front of a data packet. For example an FM modulated data packet may have a unique and distinct preamble that is different from the preamble of an AM modulated data packet.
[0019] The frequency spectrum 214 of the digitized RF signal 210 , at the output of the FFT engine 212 , is subsequently fed into both an AM demodulator 216 and an FM demodulator 218 . The demodulated information 220 from the AM demodulator 216 is bit-sliced and entered, bit-by-bit, into a correlator 222 that stores a copy of the preamble specific to the AM signal, while the demodulated information 224 from the FM demodulator 218 is bit-sliced and entered, bit-by-bit, into a correlator 226 that stores a copy of the preamble specific to the FM signal. The demodulated and bit-sliced information entering both correlators are compared with the stored preambles for a possible match. In other words, the AM and FM signals have differing preambles that permit their corresponding correlators to identify each other as a valid data signal.
[0020] In one embodiment of the invention the preambles of the AM and the FM signals may be the same, for example, to merely identify information-bearing signals. Yet, in other embodiments the preambles of the AM and the FM signals may be designed to be different for various additional considerations. For example, in an embodiment the AM and the FM signals may be orthogonal for identifying the endpoints or merely be unique for classification of the packet type (e.g. coming from a repeater or an endpoint). The preambles may even be arbitrary, or Manchester encoded for synchronization purposes.
[0021] In one embodiment the correlators may be arranged in series, illustrated in FIG. 5 . In this embodiment each of the AM demodulated signal 220 and the FM demodulated signal 224 passes through both correlators 222 and 226 for identification of a valid preamble. In an alternative embodiment there may be a single correlator 222 , illustrated in FIG. 6 . In this embodiment both the AM demodulated signal 220 and the FM demodulated signal 224 pass through correlator 222 for identification of a valid preamble. In yet another embodiment the passage of each demodulated signal 220 or 224 through a single correlator or two series correlators, for example, can be controlled by a control signal 227 in combination with two serial memory elements 221 and 223 and a multiplexer 225 , wherein the control signal 227 can be a clock signal.
[0022] Once one of the correlators 222 or 226 recognizes an input preamble as valid (appropriate AM or FM preamble), which is an indication of the existence of useful information on that particular signal carrier (e.g. data packets), the correlator provides an appropriate signal, or otherwise communicates its discovery, to a selector module 228 . The selector module 228 then connects the output of the appropriate demodulator to a DSP (Digital Signal Processing) or other decoder 230 to decode the rest of the data bits of that particular information-bearing signal, until it exhausts the information bits within the data packet. The combination of the two AM and FM demodulators 216 and 218 , the two correlators 222 and 226 , and the selector module 228 , along with their associated data paths, form a receiver “channel” 232 .
[0023] The FFT engine, the decoders, the correlators, the selector, and the DSP decoder can be all or individually implemented by one or more dedicated processors, computers, programmable gate arrays, etc., or monolithically integrated on an Application Specific Integrated Circuit (ASIC). There are no limitations for the implementation methods and apparatus regarding the functions involved in this disclosure.
[0024] In another embodiment of this invention a dual mode receiver has two or more of such channels, enabling the receiver to decode AM and FM signals simultaneously. This would be helpful in a system with different endpoints, some of which employ AM transmission while others employ FM. In this embodiment the selector module of one channel may pass the demodulated data bits of an AM signal to be decoded in the DSP decoder, while the selector module of another channel passes the demodulated data bits of an FM signal to the DSP decoder.
[0025] In yet another embodiment of this invention an AM transmitting endpoint uses an ASK (Amplitude Shift Keying) modulation method or an OOK (On-Off Keying) form, and an FM transmitting endpoint uses an FSK (Amplitude Shift Keying) modulation method.
[0026] In one embodiment of the present invention, transmitting endpoints use I-Q channels to broadcast both ASK and FSK modulated signals and the receiver's AM, FM, or AM and FM demodulators demodulate the complex output of the FFT engine; however, each channel operates in the same general manner as described before. Detailed description of the ASK and FSK modulations and I-Q channels of signal transmission abounds in the literature; nevertheless, some aspects of these methods will be briefly reviewed in the following paragraphs, as they relate to the embodiments disclosed in this application.
[0000] Processing Improvement
[0027] Modulation techniques vary a parameter of a sinusoid to represent desired information. A sinusoidal wave has three parameters that can be varied: amplitude, phase and frequency. In ASK, the amplitude of the signal is changed in response to the modulating information. Bit ‘ 1 ’ is transmitted by a signal of one particular amplitude and bit ‘ 0 ’ by a signal of different amplitude, while keeping the frequency constant. On-Off Keying (OOK) is a special form of ASK, where one of the two amplitudes is zero. In FSK, the frequency is changed in response to information, one particular frequency for a ‘ 1 ’ and another frequency for a ‘ 0 ’.
[0028] The sinusoidal carrier signals of the foregoing modulations, like any other sinusoidal waveform, can be represented as a vector whose length is the amplitude of the sine wave and its phase angle is its phase difference with a reference vector. Moreover, any vector can be written as a linear combination of orthogonal functions, called basis functions. Ideally, a minimum number of basis functions, with the following attributes, is desired for constructing a vector and forming a coordinate system:
1. each basis function has unit energy, such as (1, 0) and (0, 1) vectors; and 2. each basis function is orthogonal to all the other basis functions, represented mathematically by:
∫ - ∞ + ∞ ϕ i ( t ) ϕ j ( t ) = { 1 i = j 0 i ≠ j
[0031] FIGS. 3A and 3B are schematic diagrams of a signal presented in a Cartesian and a polar coordinate system, respectively, constructed by two basis functions φ 1 (t) and φ 2 (t). One example of such set of basis functions for a sinusoidal wave is a pair of sine and cosine functions of unit amplitude. Such basis functions, which can be represented as (1, 0) and (0, 1) vectors, are used in all real and modern communication systems. The axis defined by (1, 0) vector represents the I-channel and the one defined by (0, 1) vector represents the Q-channel. In FIG. 3A , s 1 is the I-channel projection and S 2 is the Q-channel projection of the carrier signal vector.
[0032] FIG. 3B shows the same signal in polar form, with its length equal to its amplitude and its angle ⊖ equal to its phase difference with respect to the (1, 0) reference signal vector. The coefficients s 1 represent the amplitude of the I-signal and s 2 the amplitude of the Q-signal. These amplitudes when plotted on the x- and y-axes, respectively, form the signal vector, where
Magnitude of the signal S=(s 1 2 +s 2 2 ) 1/2 Phase of the signal ⊖=tan −1 (s 2 /s 1 )
[0035] For example, if the I-channel's basis function is cos(ωt) and the Q-channel's basis function is sin(ωt), at any time t an I-Q sample of the non-modulated channel signals yields s 1 cos(ωt) and s 2 sin(ωt), from the I- and Q-channel respectively, from which the equation of the actual carrier signal can be written as:
carrier signal= s 1 cos(ω t )+ s 2 sin(ω t ) (1)
Equation 1 can also be written as
carrier signal= S [( s 1 /S )cos(ω t )+( s 2 /S )sin(ω t )] (2)
And if S is such that
S =( s 1 2 +s 2 2 ) 1/2 (3)
which results in
( s 1 /S ) 2 +( s 2 /S ) 2 =1 (4)
then there will exist an angle ⊖ for which
( s 1 /S )=cos(⊖) (5)
and
( s 2 /S )=sin(⊖) (6)
Using Equations 5 and 6, the carrier signal equation can be rewritten as
carrier signal= S [cos(⊖)cos(ω t )+sin(⊖)sin(ω t )] (7)
and be simplified to
carrier signal= S cos(ω t −⊖) (8)
where Equation 8 illustrates the fact that the resulting carrier signal has the same frequency as the basis functions along with a constant phase difference of ⊖. The FFT, data demodulation, data decoding, correlation, and data selection can all be performed in a field programmable gate array (FPGA) such as from Altera, Part No. EP1S20F484.
[0036] It is important to note that in the polar coordinate system a non-modulated sinusoidal carrier signal is simply represented by a stationary vector. This is because its amplitude remains constant as a result of being non-modulated and its phase remains constant with respect to the basis functions as a result of being a combination of the basis functions and therefore having the same frequency as the basis functions. However, any other sinusoidal signal with a different frequency than that of the basis functions (or that of the carrier signal) will be represented by a rotating vector since its phase is constantly changing with respect to the basis functions. The rotation direction of such a vector depends on whether its frequency is higher or lower than the frequency of the basis functions.
[0037] In yet another embodiment of the invention in which the transmitted signals are I-Q modulated, the proposed dual mode receiver identifies and demodulates an FM modulated signal by a mere cross-product operation which reduces the required time of the traditional demodulation by a factor of more than forty (40). As described above, the frequency deviation of an FM modulated signal from the carrier frequency manifests itself as a frequency of rotation around the origin of the polar plot, where a clockwise or a counter-clockwise rotation may be defined as a ‘ 0 ’ or a ‘ 1 ’. Therefore, data is decoded by calculating the frequency of the I-Q phasor rotation, which is the phase change divided by the elapsed time. The phase change itself is:
tan −1 [(change in Q)/(change in I)] (9)
[0038] Since new I and Q values are obtained at each sampling instance and the time between the samples are known, the phase change and the deviation frequency can be calculated to determine whether the received data presents a logic ‘0’ or a logic ‘1’.
[0039] Therefore, rate of rotation of the phasor will reflect a new input frequency and will produce a different angular change between incoming samples. By taking the difference between subsequent angle calculations, frequency changes can be detected, which provides a means for decoding the FM data. FM decoding has been done using an FFT by setting the deviation wide enough that as the carrier deviates it travels from one bin to the other. The decoder then decodes the data by monitoring the excursions in and out of the bin pairs. This requires either very narrow bins or wide deviation. Another method of FM decoding is to set the bin edge close to the carrier center frequency so that the amplitude in one bin changes as the carrier deviates in and out of the bin. By using I and Q vectors the deviation can be decoded when the carrier is anywhere within the bin. Bench testing has shown improvements in receiver sensitivity using FM modulation over AM.
[0040] Traditionally a CORDIC (COrdinate Rotation Dlgital Computer) algorithm is employed for calculating trigonometric functions. A CORDIC algorithm is an iterative method that requires no multiplications and is particularly suited for hardware implementation. However, if merely the direction of the rotation of a signal vector is required to identify a frequency deviation and demodulate a signal, the CORDIC calculations, or for that matter any other calculation for obtaining deviation frequency, will be a waste of time and resources.
[0041] After each sampling, in this embodiment of the invention, the cross-product of the sampled I-Q phasor and its preceding I-Q phasor is calculated. At each sampling, the generated I-Q phasor is of the form αi+βq, where i is a unit vector in the I-direction, q is a unit vector in the Q-direction, α is the I-channel sample value, β is the Q-channel sample value, and i×q=p, where p is a unit vector perpendicular to the I-Q plane and coming out of it toward the observer. Since the cross-product operation is not commutative, and A×B=−B×A, a change of direction in the deviation rotation of the I-Q phasor results in a change in the sign of the computed cross-product. For example, for a clockwise deviation rotation the value of the cross product of a sampled I-Q phasor with its preceding I-Q phasor sample will be a positive number:
(sampled I-Q phasor)×(preceding I-Q phasor sample)>0,
[0042] while the cross-product for a counter-clockwise rotation yields a negative number. Thus, the received data can be demodulated by merely calculating the above mentioned cross-product and observing its sign.
[0043] In addition to simplification of the computations, the cross-product of two consecutive I-Q samples provides both the FM demodulation and the digital slicing of the received data in one operation. Moreover, the cross-product proposed in this embodiment takes only three (3) machine cycles and directly provides a logic ‘1’ or a logic ‘0’, while the CORDIC method of calculating the deviation frequency takes approximately 140 machine cycles and requires further decision-making cycles to decipher the logic value of the received signal.
[0044] FIG. 4 is a flow diagram representing an example of steps involved in decoding an AM/FM AMR signal. At block 410 , an AM/FM signal is received by a receiver. At block 420 , the receiver samples and quantizes the signal. At block 430 , a frequency spectrum of the quantized signal is computed. At block 440 , separate AM and FM demodulators demodulate the received signal, using the computed frequency spectrum. At block 450 , the outputs of both the AM and the FM demodulators are checked for one of at least two valid preambles. At block 460 , a selector selects and routes, to a decoder, the output with a valid preamble. At block 470 , the decoder decodes the routed demodulated signal.
[0045] Conclusion
[0046] Unless the context clearly requires otherwise, throughout the description and the claims, the words “comprise,” “comprising,” and the like are to be construed in an inclusive sense, as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to.” As used herein, the terms “connected,” “coupled,” or any variant thereof, means any connection or coupling, either direct or indirect, between two or more elements; the coupling of connection between the elements can be physical, logical, or a combination thereof. Additionally, the words “herein,” “above,” “below,” and words of similar import, when used in this application, shall refer to this application as a whole and not to any particular portions of this application. Where the context permits, words in the above Detailed Description using the singular or plural number may also include the plural or singular number respectively. The word “or,” in reference to a list of two or more items, covers all of the following interpretations of the word: any of the items in the list, all of the items in the list, and any combination of the items in the list.
[0047] The above detailed description of embodiments of the invention is not intended to be exhaustive or to limit the invention to the precise form disclosed above. While specific embodiments of, and examples for, the invention are described above for illustrative purposes, various equivalent modifications are possible within the scope of the invention, as those skilled in the relevant art will recognize. For example, while processes or blocks are presented in a given order, alternative embodiments may perform routines having steps, or employ systems having blocks, in a different order, and some processes or blocks may be deleted, moved, added, subdivided, combined, and/or modified. Each of these processes or blocks may be implemented in a variety of different ways. Also, while processes or blocks are at times shown as being performed in series, these processes or blocks may instead be performed in parallel, or may be performed at different times.
[0048] The teachings of the invention provided herein can be applied to other systems, not necessarily the utility data collection system described above. The elements and acts of the various embodiments described above can be combined to provide further embodiments.
[0049] All of the above patents and applications and other references, including any that may be listed in accompanying filing papers, as well as the International PCT Patent Application No. ______, entitled “Frequency Shift Compensation, Such As for Use in a Wireless Utility Meter Reading Environment,” filed Mar. 30, 2005, assigned to Itron, (Attorney Docket No. 10145-8013WO), are incorporated herein by reference. Aspects of the invention can be modified, if necessary, to employ the systems, functions, and concepts of the various references described above to provide yet further embodiments of the invention.
[0050] These and other changes can be made to the invention in light of the above Detailed Description. While the above description describes certain embodiments of the invention, and describes the best mode contemplated, no matter how detailed the above appears in text, the invention can be practiced in many ways. Details of the compensation system described above may vary considerably in its implementation details, while still being encompassed by the invention disclosed herein. As noted above, particular terminology used when describing certain features or aspects of the invention should not be taken to imply that the terminology is being redefined herein to be restricted to any specific characteristics, features, or aspects of the invention with which that terminology is associated. In general, the terms used in the following claims should not be construed to limit the invention to the specific embodiments disclosed in the specification, unless the above Detailed Description section explicitly defines such terms. Accordingly, the actual scope of the invention encompasses not only the disclosed embodiments, but also all equivalent ways of practicing or implementing the invention under the claims.
[0051] While certain aspects of the invention are presented below in certain claim forms, the inventors contemplate the various aspects of the invention in any number of claim forms. For example, while only one aspect of the invention is recited as embodied in a computer-readable medium, other aspects may likewise be embodied in a computer-readable medium. Accordingly, the inventors reserve the right to add additional claims after filing the application to pursue such additional claim forms for other aspects of the invention. | Methods and apparatus demodulate and decode a plurality of AM and FM arriving signals, which permit, for example, a utility data-collecting unit to concurrently receive and decode transmitted signals of legacy transmitters as well as more recent FM based transmitters, or signals arriving from hybrid systems configured to transmit both AM and FM. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of priority to U.S. Provisional Patent Application No. 60/883,124, filed 2 Jan. 2007 and entitled “METHOD AND SYSTEM OF DETERMINING AND ISSUING USER INCENTIVES ON A WEB SERVER VIA ASSESSMENT OF USER-GENERATED CONTENT RELEVANCE AND VALUE,” which is incorporated herein by reference in its entirety. This application is also related to Applicants' pending U.S. patent application Ser. No. 11/465,731 filed on Aug. 18, 2006 and entitled “STRATEGIES FOR ANNOTATING DIGITAL MAPS,” which is also incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
[0002] Aspects of the invention relate generally to web based tools and e-commerce tools that incorporate user-generated web content, and more particularly to novel methods for providing a reward and/or incentive to a user based on the value of the user's content.
SUMMARY
[0003] Provided are computer implemented methods for rewarding a user of a web-based application, comprising: providing a web-based application accessible by a plurality of users via an interface, wherein the application interface provides for user-directed posting and retrieval of content relating to the application; monitoring use by the plurality of users of user-specific content; assessing a value of the user-specific content; determining an incentive or reward, based on the assessed value of the user-specific content; and providing the specific user with the determined incentive or reward. Also provided is a computer network apparatus or system for rewarding a user of a web-based application. Further provided are methods of data mining, comprising: providing a web-based application (e.g., geospace, E-marketing, E-photo) for sharing posted application information accessible by a plurality users using client-server interfaces; monitoring use by the plurality of users of posted data content; and identifying a subset of users thereby.
[0004] Particular aspects provide a computer implemented method for rewarding a user of a web-based application, comprising: providing a web-based application accessible by a plurality users using client-server interfaces, wherein the application interface provides for user-directed posting and retrieval of user-provided content relating to the application; monitoring use by the plurality of users of content posted by a specific user; assessing a value of the content posted by the specific user; determining an incentive or reward, based on the assessed value of the content posted by the specific user; and providing the specific user with the determined incentive or reward. In certain embodiments, the web-based application comprises at least one of a geospace system for sharing information in a geospatial context, an E-Marketplace web-based application, and an E-Photo Storage Site web-based application. In particular aspects, the content posted by the specific user comprises at least one of geospatial data, items for sale and digital images for viewing or sale. In certain embodiments, the geospatial data comprises at least one selected from the group consisting of maps, map annotations, map modifications, map path or routes, text, hyperlinks, geospatial data associated electronic files, music files, digital photographs, images and digital multimedia files. In certain implementations, monitoring use by the plurality of users of content posted by a specific user comprises the monitoring of any third party activity related to the specific user's content. In certain embodiments, the third party activity is selected from the group consisting of the number of ‘hits’ the specific user's content receives, the number of times the specific user's content is retrieved from a database, the number of unique users viewing the specific user's content, the number of users opening a user account after viewing the specific user's content, and the number of sale items viewed or purchased based on specific user's content. In particular embodiments, advertising information is associated with the specific user's content, and monitoring comprises determining the total amount of advertising revenue generated based on third party viewing of the content-associated advertisement. In certain embodiments, third party users are charged to view the specific user's content, and monitoring comprises determining a total amount of revenue generated by viewing of the content. In preferred aspects, the application comprises a geospace system for sharing information in a geospatial context having a zoom level feature wherein user-specific content is associable with one or more zoom levels, and wherein monitoring comprises tracking of a combination of zoom level, location, and time spent viewing a location at a specific zoom level, uniquely allowing identification of a specific user subset. In certain aspects, assessing the value of the content posted by the specific user comprises at least one of determining a number of ‘hits’ received by the specific user's content, determining the number of times the specific user's content is retrieved from a database, determining the number of unique users viewing the specific user's content, determining the number of users opening a user account after viewing the specific user's content, determining the total amount of advertising revenue generated based on third party viewing of user-specific content-associated advertisement, determining a total amount of revenue generated by viewing of the content, and determining the number of sale items viewed or purchased based on specific user's content. In certain embodiments, determining an incentive or reward, based on the assessed value of the content posted by the specific user comprises at least one of determining an amount of additional storage space on the server, determining an amount of access to special features of the web-based application, determining an amount of access to “professional” or subscription fee-based tools, determining an amount of access to cooperative third party web-based services, and determining an amount of free publicity or promotion. In certain embodiments, providing the specific user with the determined incentive or reward comprises at least one of providing an amount of additional storage space on the server, providing an amount of access to special features of the web-based application, providing an amount of access to “professional” or subscription fee-based tools, providing an amount of access to cooperative third party web-based services, and providing an amount of free publicity or promotion.
[0005] In certain aspects, the method further comprises determining a value of the user, based on the value of the user-specific content or a subset thereof.
[0006] Additional aspects provide a computer network apparatus or system for rewarding a user of a web-based application, comprising: a server having a processor and at least one storage device connected to the processor; a server-based application accessible by a plurality users using client-server interfaces, wherein the application interface provides for user-directed posting to, and retrieval from the server of user-provided content relating to the application; a database of content posted by the plurality of users; a stored software program operative with the processor to monitor use by the plurality of users of content posted by a specific user, assess a value of the content posted by the specific user, and determine an incentive or reward, based on the assessed value of the content posted by the specific user; and provide the incentive or reward to the user. In certain aspects, the server-based application comprises at least one of a geospace system for sharing information in a geospatial context, an E-Marketplace web-based application, and an E-Photo Storage Site web-based application. In particular embodiments, the content posted by the specific user comprises at least one of geospatial data, items for sale and digital images for viewing or sale.
[0007] Further aspects provide a method of data mining, comprising: providing a web-based geospace application for sharing information in a geospatial context accessible by a plurality users using client-server interfaces, wherein the application interface provides for user-directed posting and retrieval of user-provided geospatial data content relating to the application; monitoring use by the plurality of users of geospatial data content posted by one or more users; identifying a subset of users based on the monitored use of a defined subset of the posted geospatial data content; and providing the identified user subset to an acquiring entity for use in targeting, soliciting or otherwise interacting with the subset of users. In certain embodiments, the geospatial data comprises at least one selected from the group consisting of maps, map annotations, map modifications, map path or routes, text, hyperlinks, geospatial data associated electronic files, music files, digital photographs, images and digital multimedia files. In certain implementations, the geospace application for sharing information in a geospatial context comprises a zoom level feature wherein user-specific content is associable with one or more zoom levels, wherein monitoring comprises tracking of a combination of zoom level, location, and time spent viewing a location at a specific zoom level, uniquely allowing identification of a specific user subset.
BRIEF DESCRIPTION OF THE FIGURES
[0008] FIG. 1 shows a screen shot of a web-based geospace application for sharing information in a geospatial context accessible by a plurality users according to Example 1, herein.
[0009] FIGS. 2-6 show, according to additional embodiments, additional mapping screen shots of a web-based geospace application for sharing information in a geospatial context accessible by a plurality users according to Example 1, herein.
DETAILED DESCRIPTION
[0010] Particular aspects are directed toward a web-based tool for determining the relevance or value of user-generated web content to a third party (e.g., persons viewing the content, and/or a web-based service provider providing the content to the persons viewing it) and providing a reward and/or incentive (e.g., additional server storage space, and/or access to special features of the web based application such as preferred placement, and/or access to ‘professional’ or subscription fee-based tools, and/or free access to other (cooperative) web companies' service, and/or free publicity and/or promotion, and the like.) to the user based on the value of the user's content.
[0011] Particular aspects may be understood with reference to the following examples.
EXAMPLE 1
Exemplary GeoMonkey™ Application Embodiment Comprising Reward and/or Incentive Based on User Content Value
[0012] In one embodiment, the present invention may be used to determine the value of user-generated content that includes maps. Specifically, a web-based application referred to as GeoMonkey™ (Appendix A of this Example 1; “Preferred GeoMonkey Embodiments,” below) can be used to generate maps based, at least in part, on user input; a geospace system for sharing information in a geospatial context. As with many” web-based applications, the functionality of the GeoMonkey™ application may be divided between a web server and client computers that access the web server via the World Wide Web. As is appreciated by those of ordinary skill in the art, software for accessing the Internet and communicating with the web server, such as a web browser, may be installed on the client computer. Additional computers and databases may be communicatively coupled to the web server to provide additional storage space, information, and/or functionality.
[0013] The web server of the GeoMonkey™ application may also access other computers coupled to the Internet. For example, a client computer may send a request for a map (or other geospatial data) to the web server of the GeoMonkey™ application. The web server may access another computer via the World Wide Web to obtain data necessary to provide the requested map to the client computer. The data may then be forwarded to the client computer. In one embodiment, the map (or other geospatial data) may be provided by a third party mapping API (e.g., maps.yahoo.com) installed on a third party computer and accessible to the web server of the GeoMonkey™ application via the Internet.
[0014] The web server of the GeoMonkey™ application provides a user interface to the client computer that allows the user to send the request for a map to the web server and display the data received from the web server. The user interface may include an image or map viewer that displays an interactive map using the map data sent to the client by the web server. FIG. 1 is a copy of an exemplary user interface of the GeoMonkey application (see APPENDIX A of this Example 1), and shows an interactive map. The interactive map may be viewed using an image viewer installed on the client computer. In one embodiment, the user interface includes a special viewer for images, such as a plug-in installed in the web browser or a viewer generated using dynamic html. The interactive map includes interactive features such as panning and zooming (e.g., see Appendix A under IV; Use-Case Examples). The user may use these interactive features to create a view of the geographic map data that has significance to the user (Id). The map view may include a subset of the map data sent to the client computer by the web server. As appreciated by those of ordinary skill in the art, the client computer may send requests to the web server and/or third party computer to receive additional data required to support the interactive features of the interactive map. For example, zooming into a region of the interactive map may require additional data. To support the zooming feature, the client computer may request additional data from the web server and/or third party computer upon which the third party mapping API is installed.
[0015] After the user has created the map view, the user can annotate the map view (see see Appendix A, items 8, 10, and 11 under IV. Use-Case Examples). FIG. 1 includes the annotation “WSUV” in a box with an arrow portion pointing to the geographic location corresponding to the text. Additionally, the user may associate information and content such as text, hyperlinks, and the like with geographic locations present in the map view. Further, a user may associate electronic files with geographic locations. These electronic files may include music files, digital photographs, images, digital multimedia files, and the like. Using the GeoMonkey™ application, users can associate any type of file with a geographic location. To store electronic files on the web server or a computer communicatively coupled thereto, the GeoMonkey™ application includes a file-upload interface (e.g., see see Appendix A, item 7 under IV; Use-Case Examples). Methods and apparatuses for uploading electronic files and generating hyperlinks to those files are well known in the art.
[0016] The GeoMonkey™ application also contains a path or route creation tool that allows the user to specify a route on the map and link content to the route interface (e.g., see Appendix A, item 11 under IV; Use-Case Examples). One exemplary use of this tool includes specifying a road trip on the map view and then associating photographs taken at various locations during the road trip with the corresponding locations on the map view. The user interface also allows users to add web links to the map view that will associate web content with the geographic location on the map view. The map view and all information/content associated with that map view added by the user is referred to hereafter as “geospatial content.”
[0017] A user may wish to save geospatial content for future viewing and/or sharing. In particular, the user may wish to share his/her map views with others and/or view map views created by others based on geographic location. In one embodiment, all of the geospatial content is stored in a memory in communication with a web server, and the data entered by a map creator (author) remains unchanged. However, the underlying map (which gives the author's data geospatial context) is always dynamically loaded, so a new road subsequently entered (e.g., by another user) would appear even though the author of the map did not explicitly add the road.
[0018] To manage the storage space on the server, a user account may be created for each user (e.g., see Appendix A, item 2 under IV; Use-Case Examples). The instructions for creating a user account may reside on the web server and may provide a user interface that allows users to apply for and/or create an account by submitting personal information such as their name and email address. The instructions for creating a user account may assign a predetermined amount of storage space to each user. In one embodiment, all new users are assigned the same amount of storage space. The instructions for creating a user account may provide the user with a user name and password. Geospatial content created by users with accounts and stored on the server within the allocated space is referred to hereafter as “content.”
[0019] The content may be stored in files in memory or in a database configured to store the content. In particular embodiments, for example, the data model is based upon object-oriented data structures that represent the articles that can be displayed upon a map. The database may reside on the web server and/or on another computer in communication with the web server.
[0020] The system allows the user to ‘publish’ his/her content, by placing (at the user's request) the content in a location where it can be accessed using a world wide web URL interface (e.g., see Appendix A, item 12 under IV. Use-Case Examples). For example, a ‘publish’ button is provided on an author's map, and when the author clicks/selects this button a new web accessible page is generated that represents the author's map. In particular embodiments, the new webpage retrieves the most recent map data each time it is accessed. In certain embodiments, authors can publish to various community maps, (e.g. an events community map may contain a link to an author's marathon map)]. In particular aspects, client computers other than the user's may send a request to the web server to view the user's content. If the user has indicated to the web server that his/her content may be shared with the requester, the web server will send the content to the requestor's client computer for viewing.
[0021] In particular aspects, because a user's content may be viewed by others requesting to view it, data related to such requests to view the content may be monitored and/or collected. Particular aspects of the present invention are directed toward determining a value of a user's content and rewarding the user based on the assessed value of the content. Particular aspects include methods and/or instructions for monitoring third party activity with respect to the user's content and determining the value of the user's content based on the activity monitored. These methods and/or instructions may be executed by the web server and/or database.
[0022] The instructions for monitoring third party activity may monitor any third party activity related to user's content. For example, the instructions may count the number of times the content is viewed and/or the number of visitors viewing the content. If advertisements are included with the content or added to the user interface for viewing the content, income may be generated based on the display of the advertisements. Further, users may be charged to view content. The instructions may total the amount of revenue generated by the content (i.e., total the advertising revenue generated and/or fees collected related to viewing the content), and the like.
[0023] Methods of monitoring activities such as counting the number of hits a website receives, the number of times a record is retrieved from a database, calculating advertising revenue, and determining the number of unique users viewing the content are well known in the art. The present invention is not limited by the method used to monitor activity related to the content. In particular novel embodiments, a combination of zoom level, location, and time spent viewing a location at a specific zoom level is tracked, uniquely allowing targeting of a segment of the population based upon a very specific location and their interest based on time spent between clicks.
[0024] Particular aspects comprise instructions for determining the value of the content using data collected by the monitoring instructions. The data collected may be compared to one or more predetermined categorical ‘threshold’ values to determine the value of the content. For example, content viewed by more than a predetermined number of visitors may be considered “valuable.” Additionally, or alternatively content viewed by visitors that subsequently apply for user accounts may be considered more “valuable” than content viewed by visitors that do not apply for accounts. Content viewed by visitors that click on advertisements may be considered more “valuable” than content viewed by visitors that do not. Additionally, or alternatively the data collected related to a first content (e.g., geospatial content created with respect to a single map view) may be compared to the data collected related to a second content or all of the other content to determine the popularity of the first content. The popularity of the content may be used to determine its value.
[0025] Certain aspects may comprise instructions that may use the value of the user's content to determine a value of the user. For example, the value of the user may be determined based on the collective or aggregated value of all of the user's content or a subset thereof. Additionally, the data collected related to the content of a first user may be compared to the data collected related to another user or all of the other users to determine the popularity of the first user's content. The popularity of the user's content may be used to determine the value of the user. While exemplary methods for evaluating the value of the content and/or user have been provided herein it is apparent to those of ordinary skill in the art that a number of other application based metrics may also be used and are within the scope of the present invention. In preferred aspects, user value metrics are normalized based upon time.
[0026] Particular embodiments comprise instructions for determining an incentive and/or reward based upon the assessed value of the content and/or the value of the user. For example, in certain embodiments, a user receives X MB of additional space (see also list herein below). Instructions for determining an incentive and/or reward may be executed by the web server. In one embodiment, the user earns additional storage space by providing content that is determined to be “valuable” (e.g., deserving of reward and/or incentive), or is determined to be of some categorical level of relative value. In particular embodiments, a scale or internal scale is used, where the size of rewarded free storage is related directly or indirectly to an assessed degree of popularity.
[0027] In certain aspects, the incentive and/or reward comprises additional free server storage space, and/or access to special features of the web based application. For example, certain maps may be ‘highlighted’ on the home page. A reward or incentive may comprise access to “professional” or subscription fee-based tool, and/or free access to other (cooperative) web companies' service, and/or free publicity and/or promotion, and the like. The instructions for awarding the incentive and/or reward to the user may be executed by the web server. For example, these instructions may instruct the web server to allocate more storage space, service access, etc., to the user.
Appendix A of Example 1
Preferred GeoMonkey Embodiments
I. Overview
[0028] Certain aspects of the invention relate generally to web based tools and geospacial content mapping, and more specifically to web based tools for creating custom ‘geospatial registered’ content that can be saved, edited, and presented interactively via the World Wide Web to a user-selected audience; a geospace system for sharing information in a geospatial context.
[0029] In particular aspects, a Geospace System comprises a web based tool (works in any web browser with a web connection, visit http://geospace.vancouver.wsu.edu) for creating custom “geospatial registered” content that can be saved, edited, and presented interactively via the World Wide Web to an audience of the users choosing. Geospatial registered content means that the system uses interactive maps to associate user data with location. The Geospace System uses a third party mapping API (maps.yahoo.com) to generate the geospatial content (maps). The system allows users to add their own data to the maps and allows them to save that data associated with a location or locations for future viewing or sharing. Thus the system stores user information in a customized geo-spatial database. The system allows the users to “publish” their customized data and maps, by placing (at the users request) the content in a location where it can be accessed using a world wide web URL. In addition, the system allows users to place privacy restrictions on their data. By default the data is not publicly available. The user can than choose to make it public to the whole world, or they can make it available using password protection.
[0030] In certain embodiments, users can upload any type of file and associate that file with a location. The system has a special viewer for images. Users can store and share images based on location. Users can create annotations on the map. The system also contains a path creation tool that allows users to label and specify paths within a geospatial context (map). One common use for this tool is to specify a road trip on a map, and then upload pictures that were taken at various locations. The system also allows users to create web links on a map. Thus if a first user is zoomed into a second user's map showing, e.g., the WSU Vancouver campus, the first user will see a link to the second user's webpage.
[0031] In certain aspects, one of the key functions of the system is the ability to specify the zoom level at which a geo-located item becomes visible. Without this property maps can quickly become cluttered, because every uploaded item will be displayed no matter what the zoom level (see use-case 14 in section III). Uploading/managing data files have been uncoupled, with/by geo-spatially placing the data file. This allows users to place geo-spatial links at several locations on a map that all reference the same data file (see use-cases 7 & 8 in section III).
[0032] There are applications such as MapQuest.com which allow viewing of selected maps; however, the current systems do not allow the user to save the particular map view and then share it with another user. Users of this system can interact with maps and at any time save the current view of the map (which may contain uploaded data). Thus users can create as many different map views as they desire and save those views.
II. Applications and Exemplary Embodiments
[0033] One particular aspect of interest is the ability to build web based communities around sharing information through geo-location. There are many opportunities to customize this system for a specific market. Most subject matter can be geo-located and shared with others, whether it is for personal or commercial reasons. Examples of exemplary embodiments include but are not limited to:
[0034] (A) In one scenario, a news story unfolds wherein a major event occurs and is witnessed and photographed by a user. With this system available, the user could login, locate the site of the news story on the map, mark it with an annotation, upload the images, and publish. Pretty soon the URL to this map would circulate all over the web. People would send the link to their friends, creating a social network based around the Geospace System.
[0035] (B) Fishermen on the Columbia River. Fishermen need geo-located data from several different sources, including tide information, weather, currents, etc. This system can provide customized content that caters to specific groups of people, thus advertising could be narrowly focused.
[0036] (C) Travel Guides can be created by individuals to map out their vacations and then later add their photos for each stop they make.
[0037] Travel agencies, Airlines, Cruise lines, Touring companies etc. can map out specific travel packages or destinations complete with photos linked to the exact location of where they were taken.
[0038] (D) Specific travel interests can be mapped for different industries. For example—Vineyards and wine tasting rooms in Napa Valley, Antique car shows in the Northwest, Summer fairs and festivals in Washington, Family vacation destinations, Hiking trails and campgrounds, or even Sports & Entertainment venues.
[0039] (E) Genealogy is one of the fastest growing areas of popular research by individuals and scholars alike. They can map an ancestor's journey to a new land or pinpoint with photos where all their relatives have resided.
[0040] (F) Auto Fuel—see on one map all the current gasoline or diesel prices in your area and where they are located.
[0041] (G) News—see the major headlines for news in your area and where they took place.
[0042] (H) Real Estate agents can map their listings complete with photos and share them with their clients. Clients can then see on one map exactly where the house is located and what is around it. The most important factor in Real Estate—Location. Location. Location.
[0043] (I) Other items for sale—map where your car is on display with a photo so interested parties can go look at it with convenient instructions.
[0044] (J) Farms to buy fresh produce. So many farmers have decided to diversify their business to survive. Many have opened up their farms for U-Pick opportunities, added entertainment such as rides and cooked foods or created festivals such as the Lentil Festival in Pullman, Wash.
[0045] (K) Professional Conferences can be mapped with their locations and specific information such as deadlines and fees.
[0046] (L) National and international chains can map their store locations complete with photos of their store, directions and a listing of services.
[0047] With each niche market, web traffic will be created and an opportunity to sell advertising space will arise specifically for that market. Advertising schemes include, but are not limited to linking advertisements to the geographic location of a particular map, or providing ad space on the screen, next to a relevant map. Advertising sources include, but are not limited to small local businesses, large national chains, state or federal institutions and governments, individuals, etc.
III. Additional Embodiments
[0048] In additional embodiments, users are allowed to search published maps using a bounding box. The user of the system will be able specify a bounding box on a “search map interface”, as well as the type of information they are looking for (map, pictures, newsfeed, pdfs, etc) and keywords. By clicking on the search button, the user will start a complex query engine that will use this geo-spatial database to search on both location (using the bounding box), data type, and keywords. The search interface will return links to all published data that is within the bounding box, and meets the data type and keyword criteria.
[0049] In other embodiments, a “news feed” database is created. The news feed database uses “spiders” (programs which browse the World Wide Web in a methodical, automated manner) to search for RSS (real simple syndication) feeds online and establish their geo-location using information inside the feed or network information. Once the geo-location has been establishing, the spider will create a record in the database giving the geo-location, the web address of the RSS, as well as keywords. Users can then use the search engine (specified in new additions 1) to read news for specific locations.
[0050] In other embodiments, adapters are developed to read a wide variety of geo-spatial data formats, including but not limited to GPS data. This implementation would allow the system to be amenable to several niche markets; for example, running clubs who use a specific data format to record running information. Any type of data could be geo-located, and users could be allowed to share that data.
IV. Use-Case Examples
[0051] In software engineering, a use case is a technique for capturing the potential requirements of a new system or software change. Each use case provides one or more scenarios that convey how the system should interact with the end user or another system to achieve a specific business goal.
1 Display Login Webpage
[0052] Actor: Web user
[0053] Pre-condition: User has internet access and a web browser.
[0054] Main Scenario:
1. User navigates their web browser to the hosted site. 2. Web browser displays hosted site.
[0057] Post Condition:
User is on the geospace login page.
[0059] Exception: The web page is unable to load for any reason.
[0060] Alternative Actions:
1. An error message will display on the main page stating the reason why the web page could not be displayed properly.
2 Create User Account
[0062] Actor: Web user
[0063] Pre-condition: Use-Case 1 Display Login Webpage.
[0064] Main Scenario:
1. The user clicks on create account. 2. User's browser opens create account web page 3. User enters login name, e-mail, and password twice for verification. 4. The user clicks the create account. 5. Browser Display's User Homepage Use-Case 6.
[0070] Post Condition:
User is logged in and his ‘home page’ is displayed. A default map is selected in the view toolbar. The boundaries of this map are used to display a world region in the Yahoo map.
[0072] Exception: User name already exists.
[0073] Alternative Actions:
1. User starts over with a new login name.
3 User Logs into System
[0075] Actor: Web user
[0076] Pre-condition: Use-Case 2 Create User Account (successfully).
[0077] Main Scenario:
1. The user enters in login name and password. 2. The user clicks login button. 3. The user's home page with all interface tools is displayed. Some default view is selected and used to display the Yahoo map.
[0081] Post Condition:
User is logged in and on his ‘home page’. A default map is selected in the view toolbar. This map's boundaries are used to display a world region in the Yahoo map.
4 User Logs Out of System
[0083] Actor: Web user
[0084] Pre-condition: User is on his Home Page.
[0085] Main Scenario:
1. User clicks on logout hyperlink. 2. Browser displays main page with login displayed.
[0088] Post Condition:
User is on the geospace login page. His login status is displayed above the name and password text fields.
5 Creating a Map View
[0090] Actor: Web User
[0091] Pre-condition: User is on his Home Page.
[0092] Main Scenario:
1. The user inserts a title for the new map then clicks on the new map button. 2. The system responds by adding the map to the map view list. 3. The new map moved to the top of the list and is highlighted to indicate it is selected. Any map that was previously selected returns to its former position in the list.
[0096] Post Condition:
The view associated with the selected map has been used to change what section of the world the Yahoo map displays.
6 Selecting a Map View
[0098] Actor: Web User
[0099] Pre-condition: User is on his Home Page.
[0100] Main Scenario:
1. The user moves his cursor to the map list toolbar, and then clicks on the name of an available map. 2. The selected map is moved to the top of the list and highlighted. Any map that was previously selected returns to its former position in the list.
[0103] Post Condition:
The view associated with the selected map has been used to change what region of the world is displayed by Yahoo maps.
7 Uploading a Document
[0105] Actor: Web User
[0106] Pre-condition: User is on his Home Page.
[0107] Main Scenario:
1. The user clicks on the upload document area. 2. The system responds by bringing up a file transfer window. 3. The user browses to the directory which contains the file to be uploaded. 4. The user selects the file to be uploaded and clicks okay in the file directory window. 5. The system responds by opening a modal window requiring the user to name the file that is uploaded. 6. The user names the file to be uploaded and clicks okay. 7. The file is added to the uploaded files area.
[0115] Post Condition:
A new FiledArticle is visible in the FiledArticle toolbar. It can now be linked to the map using the ‘Add An Image’ use case. The link associated with the map and image is displayed as a link beneath the selected map.
8 Adding a Picture (or Other FiledArticle) to the Map
[0117] Actor: Web User
[0118] Pre-condition: User is on his Home Page.
[0119] Main Scenario:
1. The user must first select a location on the map that they wish to add the icon. 2. The user must click on the tool labeled “Image” (doc, or media). 3. A dropdown menu appears listing all Picture articles 4. The user selects a named article from the dropdown menu. 5. He clicks on the button ‘Add Article’ 6. A popup dialog asks the user to name the displayed article. 7. When completed, an icon representing the picture (doc, media) appears on the map.
[0127] Post Condition:
[0128] The selected view in the view toolbar shows a new link for the added picture. In the yahoo map display, a clickable icon is displayed representing the type of linked article (camera for picture . . . etcetera).
[0000] 9 Interacting with the Map/Image Interface
[0129] Actor: Web User
[0130] Pre-condition: User is on his Home Page.
[0131] Main Scenario:
The first time the user logs into the homepage the map interface should provide a world map. Additional logins should display the last map used by the user. 1. The first time the user logs into the homepage the map interface should provide a world map. Additional logins should display the last map used by the user. 2. The user can choose to use scaling buttons to increase or decrease the view scale. 3. The user can expand and shrink the map display rectangle. 4. The user can scroll in the cardinal directions using arrow buttons. 5. The user can double click to scroll to a location 6. The user can click and drag to change the perspective.
[0139] Post Condition:
[0141] The displayed view shows an area of the world which the user has selected. This display is not directly associated with any views in the view toolbar.
10 Adding an Icon to the Map
[0142] Actor: Web User
[0143] Pre-condition: User is on his Home Page.
[0144] Main Scenario:
1. The user must first select a location on the map that they wish to add the icon. 2. The user must click on the icon labeled “ICON” 3. A dropdown menu will appear. The user will need to click on the down arrow and menu options will then appear. The user can then choose either to add:
a. House b. Bank c. Church d. Telephone
4. The user will now need to click the “Add Icon” button. This will display a popup window that prompts the user to enter in a title for the icon. 5. The user will need to enter in a title for the icon in text area provided by the popup window. Once completed, the user has to click the “OK” button and the icon that was selected will be placed at the location previously determined.
[0154] Post Condition:
A new link is listed in the selected map which is associated with the path.
11 Adding a Path to the Map
[0156] Actor: Web User
[0157] Pre-condition: User is on his Home Page.
[0158] Main Scenario:
1. The user clicks on the add path icon which puts the system into path mode. 2. The user clicks on the map adding the desired path. 3. When the user is finished the user clicks the add path icon which takes the system out of path mode.
[0162] Post Condition:
A new link is listed in the selected map which is associated with the path.
12 Publishing a Map View
[0164] Actor: Web User
[0165] Pre-condition: User is on his Home Page and has at least one View in his View Toolbar.
[0166] Main Scenario:
1. The user moves his cursor over a view in the view toolbar. 2. The user clicks on the lock icon which trails the map name. 3. The lock icon switches from a closed lock icon to an open lock icon.
[0170] Post Condition:
The target view is now published and accessible via published map viewing.
13 Examining a Published Map View
[0172] Actor: Web User
[0173] Pre-condition: User is on the Login Page.
[0174] Main Scenario:
1. The user clicks on the link, “browse published maps”. 2. The page changes, prompting the user to enter the name of a publisher. 3. The user clicks on ‘Search’ 4. All published GeoViews associated with the entered name are displayed as clickable links. 5. The user clicks on a link. 6. The user enters a Published Map Page. This displays the location and contents of the selected view using Yahoo maps with movement tools.
[0181] Post Condition:
The user is on a Published Map Page. The map he selected is displayed. The same navigations tools are used as in Use-Case 9.
14 Setting the Zoom Level of an Article on the Map
[0183] Actor: Web User
[0184] Pre-condition: User has selected a map and has clicked on an article. The default zoom level values for an article span the entire range. Thus the upper bound is set to the greatest value and the lower bound is set to the smallest value. Thus the default values allow the article to be seen at all zoom levels. (However, this might result in cluttering up maps at high zoom levels, thus we added this use-case to allow users to specify the zoom levels.)
[0185] Main Scenario:
1. The user selects a “zoom level” by navigating using the zoom bar on the selected map. 2. The user can either choose to set this zoom level as the upper bound or the lower bound for the given article. The upper bound specifies that the article will not be available at zoom levels greater than this value. The lower bound specifies that the article will not be available at zoom levels less than this value. 3. The user does this for both zoom levels. If the user does not specify the zoom level for either, the default values are used.
[0189] Post Condition:
The article is only visible within the zoom range specified by the user. FIG. 1 shows an exemplary Screen Shot.
EXAMPLE 2
Exemplary E-Marketplace Embodiment
[0191] In another exemplary embodiment, an E-Marketplace web-based application example is in some respects similar to the herein described GeoMonkey™ web-based application example, except that instead of monitoring activity related to a user's geospatial content, the ‘instructions’ monitor activity related to an item offered for sale by a seller.
[0192] In particular embodiments, each seller is initially granted a predetermined amount of storage space on the web server, in which they may upload digital photographs, images, descriptions of the item, and other information related to the item for sale. As is appreciated by those of ordinary skill in the art, each seller may offer multiple items for sale at the same time and such embodiments are within the scope of the present invention. Further, persons of ordinary skill in the art will appreciate that E-Marketplace web-based applications (such as those provided by www.eBay.com, www.Amazon.com, and the like) that provide instructions allowing users to list items for sale are well known in the art.
[0193] Particular aspects of the present invention provide instructions for monitoring activity related to the item for sale and determining the value of each of the items and/or the value of the seller. For example, the value of an item may be based on at least one of the following data collected by monitoring activity related to the item for sale: the amount of revenue generated by the sale of the item; the number of visitors that view the item; the number of visitors to the item that subsequently request user accounts; the selling price of the item; and the like The value of the items that generate more revenue and/or have a higher selling price may be regarded as greater than that of items that generate less revenue and/or have lower selling prices. Items viewed by more visitors and/or more visitors that subsequently request user accounts may be considered more valuable.
[0194] The value of a seller may be based on the data collected by monitoring activity related to the items the seller has offered for sale. Data collected with respect to all of the items offered by the seller or a subset of the items offered may be considered. For example, the data collected may include at least one of: the amount of revenue generated by the sale of the seller's items; the number of visitors to the seller's items that subsequently request user accounts; the number of visitors that view the seller's items; and the like. The value of sellers who generate more revenue and/or have a higher selling price items may be regarded as greater than that of sellers who generate less revenue and/or have lower selling price items. Sellers whose items are viewed by more visitors and/or more visitors that subsequently request user accounts may be considered more valuable.
[0195] In particular aspects, the inventive E-Marketplace web-based application includes instructions for determining a reward and/or incentive such as additional storage space on the webserver, access to special features, etc. based on the value of the item and/or the value of the seller and providing that reward to the seller.
EXAMPLE 3
Exemplary E-Photo Storage Site Embodiment
[0196] In another exemplary embodiment, an E-Photo Storage Site web-based application example is in some respects similar to the GeoMonkey™ web-based application example, except instead of monitoring activity related to the user's content, the ‘instructions’ monitor activity related to digital images a user has provided to the E-Photo Storage Site. Initially, each user is granted a predetermined amount of storage space on the website server, in which they may upload digital photographs, images, descriptions of the photographs, and/or other information related to the images. The images may be viewed by or shared with third parties. Persons of ordinary skill in the art appreciate that E-Photo Storage Site web-based applications (such as those provided by www.snapfish.com, www.dotphoto.com, www.kodakgallery.com, and the like) that provide instructions allowing users to post images and share them with others are well known in the art.
[0197] The present invention provides instructions for monitoring activity related to the image posted and determining the value of each of the image and/or the value of the user who posted the image. For example, the value of the image may be based on at least one of the following data collected by monitoring activity related to the image: the amount of revenue generated by the image (e.g., via advertising, fees, and/or purchases of copies (or prints) of the image); the number of visitors that view the image; the number of visitors to the image that subsequently request user accounts; and the like. The value of the images that generate more revenue may be regarded as greater than that of images that generate less revenue. Images viewed by more visitors and/or more visitors that subsequently request user accounts may be considered more valuable.
[0198] The value of the user may be based on the data collected by monitoring activity related to the images the user has shared. Data collected with respect to all of the images posted by the user or a subset of the images may be considered. The data collected may include at least one of: the amount of revenue generated by the user's images (i.e., via advertising, fees, and/or purchases of copies (or prints) of the images); the number of visitors to the user's images that subsequently request user accounts; the number of visitors that view the user's images; and the like. The value of users who generate more revenue may be greater than that of users who generate less revenue. Users whose images are viewed by more visitors and/or more visitors that subsequently request user accounts may be considered more valuable.
[0199] In certain aspects, the E-Photo Storage Site web-based application includes instructions for determining the reward and/or incentive such as additional storage space on the webserver, access to special features, etc. based on the value of the image and/or the value of the user and providing that reward to the user. | Provided are computer implemented methods for rewarding a user of a web-based application, comprising: providing a web-based application accessible by a plurality of users via an interface, wherein the application interface provides for user-directed posting and retrieval of content relating to the application; monitoring use by the plurality of users of user-specific content; assessing a value of the user-specific content; determining an incentive or reward, based on the assessed value of the user-specific content; and providing the specific user with the determined incentive or reward. Also provided is a computer network apparatus or system for rewarding a user of a web-based application. Further provided are methods of data mining, comprising: providing a web-based application (e.g., geospace, E-marketing, E-photo) for sharing posted application information accessible by a plurality users using client-server interfaces; monitoring use by the plurality of users of posted data content; and identifying a subset of users thereby. | 6 |
This is a Division, of application Ser. No. 08/296,244 filed on Aug. 25 1994 now U.S. Pat. No. 5,556,922.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to methods for preparing aqueous dispersions comprising alkyl (meth)acrylates which are suitable as pressure sensitive adhesives.
2. Description of the Background Art:
Pressure sensitive adhesives (also known as “self-adhesive compounds”) form a permanently adhesive film which, under slight pressure, adheres immediately to various surfaces at room temperature. (See 1985, “Ullmann's Encyclopedia of Industrial Chemistry”, 5th Ed., Vol. A1, pub. VCH, pp. 235-236.)
Pressure sensitive adhesives are used principally for coating of supports, such as those based on paper or polymer films or sheets. These coated supports provide products such as self-stick labels, adhesive tapes and self-stick film which have a characteristic broad spectrum of properties, including:
short-contact-time adhesion of the adhesive film to the substrate surface (“tack”) and
water-resistance of the adhesive layer.
Understandably, a single pressure sensitive adhesive cannot display all desirable properties, particularly those properties which are mutually exclusive. Accordingly, a compromise must be made and an “optimized” set of properties must be found for each application. Often, product optimization is accomplished by the use of various auxiliary substances, such as synthetic resins, tackifiers, crosslinking agents and viscosity regulators. The particular adhesives, depending on their compositions, are applied to the substrates in the form of solutions, dispersions, or even melts. After the adhesive sets, the layer of pressure sensitive adhesive is present as a film on the support. Prior to use, the film is often covered, with a suitable anti-adhesive material, such as a silicone-based film. However, adhesive tapes may also be employed with no covering layer (see “Ullmann's Encyclopedia”, loc.cit., 258). Natural and synthetic rubbers, in modified form, may be used as adhesive materials for pressure sensitive adhesives. Also frequently used are adhesives prepared from poly(meth)acrylic acid esters, polyvinyl ethers, and polyisobutylene, often in combination with phenolformaldehyde-or hydrocarbon resins.
Polyacrylate dispersions or vinyl acetate copolymers are also often used as so-called “dispersion pressure sensitive adhesives”, to which resins are often added.
The problem with most pressure sensitive adhesives can be better understood by way of an illustrative example based on adhesive tapes made of (corona treated) polypropylene strip material. Such adhesive tapes are often used as packaging tape for cardboard boxes. The most important requirements in this area of application are for good adhesion of the tape to the surface of the box, and good internal strength (or cohesion) of the adhesive layer. In most cases, it has not been possible to satisfy both of these requirements simultaneously, because many of the means of producing good cohesion are detrimental to good adhesion. For example, while it is known that cohesion increases with increasing molecular weight of the polymer, adhesion decreases correspondingly.
In Ullmann, loc.cit., it is stated:
“There are indications that a pressure sensitive adhesive must always be comprised of
a high polymer principal resin, which contributes cohesion and the specific adhesion, and
so-called tackifiers, wherewith in many systems the latter may be replaced by low molecular weight components of the principal polymer. To increase cohesion, in many systems the principal resin is crosslinked (or vulcanized, in the case of rubbers) after application.”
Certain techniques for preparing the adhesive by emulsion polymerization have found favor, despite the fact that a number of variants are known. Thus, the use of ammonium peroxydisulfate (APS) as an initiator has become standard procedure. Conventionally peroxydisulfate compounds are used as initiators in amounts of 0.001-0.05 wt. % (based on the weight of the monomers) (see Houben and Weyl, 1961, “Methoden der Organischen Chemie”, 4th Ed., Vol XIV/1, pub. G. Thieme, p. 1049; and 1968, Rauch-Puntigam, H. and Voelker, Th., “Acryl- und Methacrylvergindungen”, pub. Springer-Verlag, 221).
Thus, it is desired in the art to improve the overall set of properties of the known acrylate pressure sensitive adhesives, particularly their adhesion and cohesion, without requiring the use of auxiliary additives as noted above.
SUMMARY OF THE INVENTION
Accordingly, one object of the present invention is to provide a method for preparing a pressure sensitive adhesive composition which has both high adhesion and high cohesion.
A further object of the present invention is to provide a pressure sensitive adhesive prepared by the method of the present invention, in which the adhesive composition has both good adhesion and good cohesion.
A further object of the present invention is to provide a method for preparing a pressure sensitive adhesive having both high adhesion and high cohesion, without the use of conventional auxiliary additives to provide such adhesion and cohesion.
These and other objects of the present invention have been satisfied by the discovery that dispersions for pressure sensitive adhesives can be prepared by a method for preparing a dispersion, wherein the dispersions comprise a copolymer (CP) comprised of units of n-butyl acrylate and (meth)acrylic acid; the method comprising the steps of polymerizing an aqueous emulsion (EM) containing butyl acrylate, an anionic emulsifier and a non-ionic emulsifier, in the aqueous phase, under heating and in the presence of at least one water-soluble initiator (IN) of formula (I)
M R 1 (I)
where M represents a metal cation, and
R1 represents an anion of a peroxyacid or azo-group-containing acid,
wherein said (IN) is present in an amount of 0.5-1.5 wt. % (based on weight of the monomers);
emulsifying-in (meth)acrylic acid while maintaining an elevated reaction temperature; and
adding a second initiator (RI) to complete the polymerization.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The starting point for the present invention is a principal resin comprised of butyl acrylate in combination with relatively small amounts (<15 wt. %) of (meth)acrylic acid.
The present invention relates to a method of producing dispersions for pressure sensitive adhesives, which dispersions are based on a copolymer CP comprised of units of n-butyl acrylate and small amounts of (meth)acrylic acid, wherewith, in a first step, butyl acrylate is polymerized, preferably as a core, in aqueous phase preferably under the conditions of a core and shell polymerization, in the presence of water-soluble initiators IN of formula I
M R 1 (I)
where M represents a metal cation such as sodium or potassium, and
R1 represents the anion of a peroxyacid or azo-group-containing acid,
which initiators are present in the amount of 1±0.5 wt. % (based on the weight of the aqueous phase); and in a second step butyl acrylate and (meth)acrylic acid are polymerized, in an overall ratio in the range 99.5:0.5 to 90:10 in terms of parts by weight (pbw), preferably 98:2 to 96:4 in terms of pbw, wherewith the (weight) ratio of core to shell is preferably in the range 30:70 to 70:30, particularly preferably 50:50, and the polymerization is carried out to completion, wherewith preferably at the end of the polymerization the (meth)acrylic acid groups are neutralized with ammonia (neutralization pH 9.5). The procedure is performed according to customary methods of emulsion polymerization, such as in a semicontinuous “feed” process or in a batch process (see Houben and Weyl, loc.cit., Vol. XIV/I).
According to the present invention, the internal strength of the adhesive layer can be increased by copolymerization with various crosslinking agent systems in various concentrations (one might mention, e.g., allyl (meth)acrylate, ethylene glycol dimethacrylate, methacrylamide, N-(hydroxymethyl) methacrylamide, and triallyl cyanurate) (see 1968, Rauch-Puntigam, H. and Voelker, Th., loc.cit.). However, systems crosslinked in this way ordinarily have low adhesion, and the adhesion is not increased to a significant degree by regulating molecular weight in the emulsion polymerization.
When the method of the present invention is used, however, the required set of properties—very good cohesion along with excellent adhesion—can be surprisingly achieved in n-butylacrylate (meth)acrylic acid-based polymers produced by emulsion polymerization, if one employs special water-soluble initiators IN in amounts which are very large compared with the concentrations customarily used.
In accordance with the present invention, the desired set of properties for pressure sensitive adhesive films is fully realized only if the dispersions for the pressure sensitive adhesives are polymerized by the method of core and shell polymerization. (While the method employed according to the invention will be designated a “core and shell” method, This designation is not meant to limit the present invention to an ideal core-shell polymer but can also include structures with only partial “shells” on the “core” portion also. Further, there is no need to accept as given certain model concepts associated therewith.) In the core and shell polymerization, the core will be comprised of butyl acrylate. If one tries homogeneous incorporation of (meth)acrylic acid or a variation of the core and shell conditions, the result is usually a major deterioration of temperature resistance of the final polymer.
The initiators IN are, per se, known compounds (see Brandrup, J., and Immergut, E. H., 1989, “Polymer Handbook”, 3rd Ed, Vol. II-1, pub. J. Wiley). The initiators IN include azo compounds, which may preferably be selected from among azo compounds represented by formula I-A
where R2 represents CH 3 , and
n represents a number from 1 to 4.
Most preferably, the initiators IN of formula I are selected from the group consisting of metal salts of peroxydisulfuric acid, such as potassium peroxydisulfate (KPS), sodium peroxydisulfate (NaPS), and the metal salts (e.g. K or Na salt) of 4,4′-azobis-(4-cyanovaleric acid). However, the conventionally used ammonium salts should not be used. The final polymerization may advantageously be promoted by addition of a redox initiator RI. Suitable redox initiators include those listed in “Kirk-Othmer Encyclopedia of Chemical Technology” Vol. 13, pp. 355-373 (1981), which is hereby incorporated by reference, with the redox initiators tert-butyl hydroperoxide/ferrous sulfate and tert-butyl hydroperoxide/sodium hydroxymethylsulfinate being preferred.
Based on available knowledge, homogeneous incorporation of the (meth)acrylic acid and appreciable variation of the core/shell ratio beyond the range stated leads to a substantial decrease in temperature resistance of the adhesive. If the (meth)acrylic acid groups are neutralized by ammonia at the end of the polymerization, the processibility of the dispersion (shear stability) and its application characteristics (film formation) are improved. Determination of the acid distribution in the dispersions shows a relatively large proportion of acid-group-containing oligomers (M w ≦400 g/mol) in the serum, which oligomers form in the aqueous phase as a result of the large amount and reactivity of the starting radicals (oligomer radicals). While the present inventors do not wish to be limited by the following hypothesis, the inventors propose that the increased content of acid group-containing oligomers in the serum of the dispersion is responsible for the observed major increase in the adhesion of the polymer film, somewhat in the manner of a tackifier.
The pressure sensitive adhesives of the present invention are produced by the method of emulsion polymerization, which is, per se, known (see Houben and Weyl, 1987, loc.cit., Vol. E20, pp. 1150-1156; 1992, “Ullmann's”, loc.cit., Vol. 21 A; and Rauch-Puntigam and Voelker, 1967, loc.cit., pp. 217-230).
While the general course employed in the method relies on the state of the art, the particular steps performed provide a novel result. Particularly, surface-active substances with an HLB (hydrophilic-lipophilic balance) value >12 are used as emulsifiers; these surface active substances include anionic emulsifiers such as sulfates and sulfonates of oligoglycol ethers, and particularly non-ionic emulsifiers such as oxyethylation products of alkylphenols and alkanols having 12-20 C. atoms. Examples of anionic emulsifiers which might be mentioned are sulfosuccinic acid esters, which are effective at pH values below the neutral point.
Specifically, a preferred embodiment of the present method can be performed as follows:
To a reaction vessel equipped with a stirring apparatus, temperature control means, and dosing means are changed completely desalinated water (comprising c. 35% of the aqueous phase), an emulsifier (such as c. 0.03% of a sulfosuccinic acid ester), and an acrylate-based seed latex (having particle diameter of 50 nm for example).
The mixture thus charged is heated to 80° C., and c. 10 wt. % of the total amount of initiator (neutralized with a suitable alkali, such as sodium hydrogen carbonate, and dissolved in approximately twice the amount of water) is added.
To this solution is added, portionwise, over a few hours at the chosen temperature, generally from 50 to 120° C., preferably from 65 to 90° C., under stirring, an emulsion of butyl acrylate in desalinated water, which emulsion contains the non-ionic surfactant as well as the anionic emulsifier (in a preferred weight ratio of the surfactant to the emulsifier of c. 1:4).
The emulsion, which may contain butyl acrylate and water in a ratio of c. 2:1 by weight, also preferably contains c. 0.5 wt. % of an initiator IN of formula I, neutralized with a suitable alkali hydrogen carbonate.
After about half of the feed time, the (meth)acrylic acid is emulsified-in, without interrupting the feed.
Preferably, the reaction mixture is held at elevated temperature (generally the same temperature used for the initial polymerization step) for the desired period, such as 1 hr, and then is allowed to cool to room temperature.
The final polymerization may then be carried out at a slightly lower temperature, generally less than or equal to 70° C., preferably with the addition of a redox initiator RI, such as tert-butyl hydroperoxide/ferrous sulfate or tert-butyl hydroperoxide/sodium hydroxymethylsulfinate.
Finally, defoamants such as a hydrocarbon-fat emulsion are added, and the pH adjusted to alkaline (pH 9.5±0.5) with ammonia.
The resulting dispersions for pressure sensitive adhesives are then applied in simple fashion to the desired substrate (support), such as the above-mentioned (corona-treated) polypropylene strip material. Application of the disperser made to the support by any conventional method, such as may be, by means of a doctor blade method, at a thickness such that after evaporation of the water and film formation the film weight of the remaining pressure sensitive adhesive layer is in the range 20-30 g/sq m.
The adhesive films produced by the dispersions of the present invention show very good adhesion as well as good temperature resistance, in technical tests. It should be noted that the present adhesive dispersions produce adhesive films with good adhesion and thermal resistance solely on the basis of the production method of the present invention, and without addition of tackifiers or condensation resins.
Having generally described this invention, a further understanding can be obtained by reference to certain specific examples which are provided herein for purposes of illustration only and are not intended to be limiting unless otherwise specified.
EXAMPLES
Adhesion was measured by Test Method No. 1 of the PSTC (Pressure Sensitive Tape Council).
The cohesion of the adhesive films was characterized by measuring the temperature resistance (PSTC Test Method No. 7).
The “tack” was determined by PSTC Test No. 6 (see PSTC, “Test Methods for Pressure sensitive Tapes”, 9th Ed.).
A. Production of the Adhesive Dispersions
Example 1
11.22 kg desalinated water, 0.0033 kg diisohexyl sulfosuccinate (Rewopol® SB MB 80), and 0.042 kg of an acrylate-based seed latex (particle diameter 50 nm) were heated to 80° C. in a reaction vessel equipped with a stirrer, temperature control means, and a dosing device. At this temperature, 0.028 kg initiator (4,4′azobis-(4cyanovaleric acid) dissolved in 0.052 kg water and neutralized with 0.018 kg NAHCO 3 ) was added. To this solution an emulsion produced from the following components was added portionwise at 80° C. under stirring, over a period of 4 hr:
41.16 kg butyl acrylate
20.04 kg desalinated water
0.175 kg diisohexyl sulfosuccinate
0.175 kg 25% aqueous solution of a nonionic surfactant (Marlipal® 013/400) (a C 13 keto alcohol with 40 mol ethylene oxide)
2.1 kg 4,4′-azobis-(4-cyanovaleric acid) (“azo”) solution, comprised of 0.21 kg “azo”, 1.89 kg water, and 0.135 kg NaHCO 3 .
After 2 hr of the portionwise feed of the emulsion, 0.84 kg methacrylic acid was emulsified-in without interruption of the feed. After completion of the feed, the reaction mixture was maintained at 80° C. for an additional 1 hr and then was cooled to room temperature. During this cooling, the final polymerization was carried out at 70° C. by addition of 0.035 kg tert-butyl hydroperoxide, 0.0003 kg ferrous sulfate, and 0.028 kg sodium hydroxymethylsulfinate. 0.011 kg defoamant (Nopco® NXZ, a hydrocarbon/fat emulsion) was added at 40° C., and the pH was adjusted with ammonia.
Standard Characteristics of the Dispersions for Pressure Sensitive Adhesives
Solids content (%)
53 ± 1
Viscosity (mPa-sec)
100-600
Particle radius, r NS (nm),
250 ± 50
measured with a Nanosizer (R)
by photocorrelation microscopy
pH
9.5 ± 0.5.
The following Table reports on other Examples analogous to Example 1, wherein the polymer composition was the same and the dispersions for pressure sensitive adhesives differed only as shown in the initiator system or the amount of initiator used.
TABLE
Tack
Adhesion
Temperature
(mm),
Ex-
Initiator, IN
(N/25
resistance
measured
am-
(wt. %, based
mm), measured
(hr), measured
by PSTC
ple
on the weight of
by PSTC Test
by PSTC Test
Test Method
No.
the water phase)
Method No. 1
Method No. 7
No. 6
2.
0.75%
7.0
>170
70
“Azo” (NaHCO 3 )
is *
3.
1.0% “Azo”
7.1
>170
90
(NaHCO 3 )
4.
1% KPS,
8.3
>120
90
potassium
peroxydisulfate
5.
0.75% KPS
7.5
>100
60
6.
1% NaPS, sodium
8.3
>100
peroxydisulfate
7.
0.35% “Azo”
8.5
>170
20
(NaHCO 3 ) +
0.5% KPS
8.
0.25% “Azo”
5.2
<10
(NaHCO 3 )
9.
1% APS,
9.5
<2
60
ammonium
peroxydisulfate
10.
1% “Azo”
7.1
<1
(NH 4 HCO 3 )
*) 4,4′-azobis-(4-cyanovaleric acid) neutralized with NaHCO 3
As seen from the above Table, the adhesive films of the present invention have the desired set of properties (high adhesion and high temperature resistance) when metal-salt-containing initiators are used in sufficient amounts in producing the dispersions. When the corresponding ammonium-neutralized form of the initiator (such as APS) is used for the polymerization, the temperature stability (i.e. cohesion) is greatly reduced. If the amount of initiator is reduced substantially (e.g. 4,4′-azobis-(4-cyano valeric acid) in the amount of 0.25%, neutralized with NaHCO 3 )′ the adhesive film produced has unacceptably poor properties. | A method for preparing a dispersion for a pressure sensitive adhesive is provided, wherein the dispersions contain a copolymer (CP) having units of butyl acrylate and meth)acrylic acid; the method involving the steps of polymerizing an aqueous emulsion (EM) containing butyl acrylate, an anionic emulsifier and a non-ionic emulsifier, in the aqueous phase, under heating and in the presence of at least one water-soluble initiator (IN) of formula (I)
MR 1 (I)
where M represents a metal cation, and
R1 represents an anion of a peroxyacid or azo-group-containing acid,
wherein (IN) is present in an amount of 0.5-1.5 wt. % (based on weight of the monomers);
emulsifying-in (meth)acrylic acid while maintaining an elevated reaction temperature; and
adding a second initiator (RI) to complete the polymerization. | 8 |
BACKGROUND OF THE INVENTION
The present invention relates to a stable formulation of omeprazole. It is well known that omeprazole is sensitive to acidic conditions and after contact with an acid, omeprazole will degrade and will not function in its intended manner. Initially, alkaline materials were added to a core of omeprazole and later an enteric coating was applied over the core to prevent the omeprazole from contacting the acidic pH conditions of the stomach. This approach is satisfactory if the product is administered within a short time after it is manufactured but if the product is stored under ambient conditions, the acidic residue of the enteric coating appears to degrade the omeprazole before it is administered to a patient. To solve this problem, the prior art has used a separate layer of a coating agent to coat a pellet core which contains omeprazole and an alkaline material which is thereafter coated with the enteric coating. This technique is described in U.S. Pat. No. 4,786,505. In addition WO 96/24338 discloses the use of an in situ formed interlayer that is based on the reaction of an aqueous enteric coating material with an alkaline material in the core.
This dual layer coating technique requires the application of two separate functional coating operations which increases the length of the manufacturing process and the cost of the product. The applicants have surprisingly discovered a coating system which avoids the need to use a coating layer to separate the omeprazole core from the enteric coating layer in an omeprazole dosage form. The separate coating system is based on the combined use of an enteric coating agent which is applied to a pelletized core or a granular core of omeprazole as a suspension in a suitable solvent.
The applicants have also surprisingly discovered that arginine or lysine can be used as a pH stabilizing agent
SUMMARY OF THE INVENTION
The present invention provides a novel stable pharmaceutical composition of omeprazole for oral administration which consists essentially of:
(a) a core of omeprazole or a pharmaceutically equivalent salt, a filler and an alkaline material selected from the group consisting of lysine and arginine; and
(b) a single layer of coating on said core which comprises a layer of an enteric coating agent applied from an organic based solvent coating system.
The core of the pharmaceutical composition can be in the form of a compressed tablet which is further comprised essentially of a surface active agent, and a binder. Alternatively, the pharmaceutical composition can have a pelleted core which is further comprised essentially of an inert core component, a surface active agent and a binder.
Accordingly, it is a primary object of this invention to provide a pharmaceutical dosage formulation of omeprazole which is stable upon prolonged storage, is stable when administered to a patient and is capable of providing the desired therapeutic effect.
It is also an object of this invention to provide a pharmaceutical dosage form of omeprazole which is bioequivalent to dosage forms of omeprazole which have an intermediate layer of an inert coating material.
It is also an object of this invention to provide a stable dosage form of omeprazole which may be produced without the need to provide an intermediate coating layer that separates the omeprazole containing core from the enteric coating layer.
These and other objects of the invention will become apparent from a review of the appended specification.
DETAILED DESCRIPTION OF THE INVENTION
The omeprazole formulation of the invention is preferably based on a core of omeprazole or pharmaceutically equivalent salt, a filler and an alkaline material selected from the group consisting of arginine or lysine; and a single layer of coating on said core which comprises a layer of an enteric coating agent applied from an organic solvent based system. The Omeprazole core can either be pelleted or tabletted as described herein.
In the case of both the pelleted form and the tabletted form of the core a filler is used. A filler is used as a granulation substrate. Sugars such as lactose, dextrose, sucrose, maltose, or microcrystalline cellulose and the like may be used as fillers in either the pellet or the granulation composition. In the case of the pelleted form the filler may comprise from 20 to 90 wt % and preferably 65-85 wt % based on the total weight of the drug layer composition. In the case of the tabletted form the filler may comprise from 20 to 60 wt % and preferably 20 to 40 wt % based on the total weight of the granulation. In the case of the tabletted form of the invention a tablet disintegrant may be added which comprises corn starch, potato starch, croscarmelose sodium, crospovidone and sodium starch glycolate in an effective amount. An effective amount which may be from 3 to 10 wt % based on the total weight of the granulation.
In the case of both the tabletted form and the pelleted form of the core an alkaline agent that is either lysine or arginine is used as a stabilizer. In the case of the tabletted form a level of from 20 to 60 wt % and preferably 30 to 55 wt % based on the weight of the granulation may be employed. In the case of the pelleted form a level of from 0.5 to 10 wt % and preferably 1 to 3 wt % based on the weight of the pellet may be employed.
In the case of the pelleted form and the tabletted form of the invention an enteric coating agent is placed over the core. In both cases the enteric coating may comprise an acid resisting material which resists acid up to a pH of above about 5.0 or higher which is selected from the group consisting of cellulose acetate phthalate, hydroxypropylmethyl cellulose phthalate, polyvinyl acetate phthalate, carboxymethylethylcellulose, Eudragit L (poly(methacrylic acid, methylmethacrylate), 1:1 ratio; MW (No. Av. 135,000—USP Type A) or Eudragit S (poly(methacrylic acid, methylmethacrylate, 1:2 ratio MW (No. Av. 135,000—USP Type B) and mixtures thereof.
The enteric coating agent may also include an inert processing aid in an amount in the case of the tabletted form from 15 to 55 wt % and preferably 20 to 45 wt % based on the total weight of the acid resisting component and the inert processing aid. In the case of the pelleted form the inert processing aid is preferably in an amount from 5 to 50 wt % and most preferably 10-20 wt %. The inert processing aids include finely divided forms of talc, silicon dioxide, magnesium stearate etc. Typical solvents which may be used to apply the acid resisting component-inert processing aid mixture include isopropyl alcohol, acetone, methylene chloride and the like. Generally the acid resistant component-inert processing aid mixture will be applied from a 5 to 20 wt % of acid resisting component-inert processing aid mixture based on the total weight of the solvent and the acid resistant component-inert processing aid.
In the case of both the tabletted form and the pelleted form of the invention omeprazole or a pharmaceutically equivalent salt is used in the core. In the tabletted formulation the omeprazole may comprise from 5 to 70 wt % and preferably 10 to 30 wt % of the granulation. In the pelleted form the Omeprazole may comprise from 10 to 50 wt % and preferably 10 to 20 wt % of the drug layer composition.
A surface active agent is used in both the tabletted and the pelleted form of the invention. The surface active agent may be any pharmaceutically acceptable, non-toxic surfactant. Suitable surface active agents include sodium lauryl sulfate, polysorbate 20, polysorbate 40, polysorbate 60, polysorbate 80 and the like. The surface active agent may be present at a level of from 0.1 to 5 wt %. In the case of the tabletted form the surface active agent is preferably 0.20 to 2.0 wt % based on the total weight of the granulation. In the pelleted form the surface active agent is preferably 0.20 to 2.0 wt % of the total weight of the drug layer composition.
The binder is used in both the tabletted and the pelleted form of the invention. The binder may be any pharmaceutically acceptable, non-toxic pharmaceutically acceptable binder. The binder is preferably a water soluble polymer of the group consisting of polyvinyl alcohol, polyvinylpyrrolidone, methylcellulose, hydroxypropyl cellulose, hydroxymethyl cellulose and the like. A water soluble binder is preferred which is applied from an aqueous medium such as water at a level of from 0.1 to 10 wt % and preferably from 0.25 to 7.5 wt % of binder based on the total weight of the granulation.
In the case of the tabletted form of the invention a granulation is formed by contacting the alkaline agent, the omeprazole, the surface active agent and the binder with a medium which may comprise any low viscosity solvent such as water, isopropyl alcohol, acetone, ethanol or the like. When fluids such as water are employed, this will usually require a weight of fluid which is about three times the weight of the dry components of the coating composition.
After the granulation is formed and dried, the granulation is tabletted and the tablets are directly coated with the enteric coating agent. A color imparting agent may be added to the enteric coating agent mixture or a rapidly dissolving seal coat containing color may be coated over the enteric coating agent layer provided that the seal coat is compatible with and does not affect the dissolution of the enteric coating layer. The rapidly dissolving seal coat may comprise Opadry pink which comprises approximately 91 wt % hydroxypropyl methylcellulose (E-6), color and 9 wt % polyethylene glycol which is applied as a 8-15% w/w solution in purified water. In addition the color may be provided as Chromateric which is available from Crompton & Knowles. This product contains water, talc, TiO 2 , triethyl citrate, propylene glycol, synthetic red iron oxide, potassium sorbate, xanthan gum, sodium citrate and synthetic yellow iron oxide. If desired, conventional sugar based seal coats may be used which contain FDA certified dyes.
In the case of a pelleted form the invention is preferably based on pellets having a core forming inert component which may comprise a starch or sugar sphere such as non-pareil sugar seeds having an average size of 14 to 35 mesh, preferably about 18 to 20 mesh. The core forming inert component is coated with a formulation which comprises Omeprazole, a surface active agent, a filler, an alkaline material that is either lysine or arginine and a binder, which are collectively referred to as the drug layer composition. The core forming inert component is employed at 1:1 to 5:1 and preferably from 2:1 to 3:1 weight ratio to the drug layer composition.
The cores are formed by spraying the non-pareil seeds with an aqueous or non-aqueous suspension which contains the alkaline agent, the omeprazole, the surface active agent and the binder. The suspension medium may comprise any low viscosity solvent such as water, isopropyl alcohol, acetone, ethanol or the like. When fluids such as water are employed, this will usually require a weight of fluid which is about seven times the weight of the dry components of the coating composition.
After the cores are dried, the cores are coated with the enteric coating agent. A color imparting agent may be added to the enteric coating agent mixture or a rapidly dissolving seal coat over the enteric coating agent layer provided that the seal coat is compatible with and does no affect the dissolution of the enteric coating layer.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Examples 1 to 5 describe a tabletted form of the invention and Example 6 describes a pelleted form of the invention.
EXAMPLE 1
Granulation.
A granulation containing omeprazole is formed in a fluid bed coater using a top spray granulation forming suspension containing omeprazole, micronized to 95% less than 15 microns, 5% w/w of the total amount of L-arginine, polyvinyl pyrrolidone, sodium lauryl sulfate and purified water which is sprayed onto a mixture of microcrystalline cellulose, 95% w/w of the total amount of L-arginine and sodium starch glycolate. The formulation for making the granulation has the following composition:
povidone, USP (Plasdone K90)
100.0
g
sodium starch glycolate
100.0
g
sodium lauryl sulfate, NF/USP
6.0
g
microcrystalline cellulose (AvicelPH101)
965.6
g
L-arginine, USP/FCC
1020.0
g
omeprazole, USP (micronized)
340.0
g
purified water, USP
1100.0
g
Tabletting.
The granulation is tabletted into tablets containing 20 mg of omeprazole by first mixing the omeprazole granules with glyceryl monostearate:
omeprazole granules
118.0
g
glyceryl monostearate (Myvaplex)
6.0
g
Tabletting tools: 0.2812″
target weight
:
124
mg/tab
target hardness
:
7
Kp
LOD of granules
:
less than 3%
Enteric Coating.
An enteric coating is applied to prepare enteric coated tablets as follows:
omeprazole tablets
124.0
g
(prepared above)
hydroxypropyl methylcellulose
14.7
g
phthalate
talc
4.2
g
acetyl tributyl citrate
2.9
g
acetone
148.0
g
isopropyl alcohol
148.0
g
The solid coating materials were dissolved in the acetone and isopropyl alcohol and this solution was coated onto the omeprazole tablets using a perforated pan
Seal Coat:
A seal coat was applied to the enteric coated tablets as follows:
Enteric coated tablet
146.0
g
Opadry II pink
4.5
g
Water
450.0
g
The seal coat was applied onto the enteric coated omeprazole tablets using a perforated pan coater.
EXAMPLE 2
Granulation.
A granulation containing omeprazole is formed in fluid bed coater using a top spray granulation forming suspension containing omeprazole, micronized to 95% less than 15 microns, 2.68% w/w of the total amount of L-arginine, polyvinyl pyrrolidone, polysorbate 80 and purified water which is sprayed onto a mixture of microcrystalline cellulose and 95.0% w/w of the total amount of L-arginine. The formulation for making the granulation has the following composition:
mg/tablet
povidone, USP (Plasdone K90)
5.88
polysorbate 80 (Tween 80)
0.58
L-arginine, USP/FCC
60.0
omeprazole, USP (micronized)
20.0
microcrystalline cellulose (Avicel PH102)
25.54
purified water, USP
n/a
Tabletting.
The granulation is tabletted into tablets containing 20 mg of omeprazole by first mixing the omeprazole granules with glyceryl monostearate:
omeprazole granules
112.0
mg
glyceryl monostearate (Myvaplex)
6.8
mg
crospovidone XL
16.2
mg
Tabletting tools: 0.2812″
target weight : 135 mg/tab
target hardness : 7 Kp
LOD of granules : less than 3%
Enteric Coating.
An enteric coating was applied to prepare enteric coated tablets as follows:
omeprazole tablets
135.0
mg
(prepared above)
Eudragit L30D-55
14.0
mg
color (Chromateric)
7.0
mg
1M NaOH (to adjust pH to 5.0)qs
na
Purified water qs
na
The solid coating materials were dispersed in the water and this mixture was coated onto the omeprazole tablets using a perforated pan.
EXAMPLE 3
Granulation.
A granulation containing omeprazole is formed in fluid bed coater using a top spray granulation forming suspension containing omeprazole, micronized to 95% less than 15 microns, 5.0% w/w of the total amount of L-arginine, polyvinyl pyrrolidone, sodium lauryl sulfate and purified water which is sprayed onto a mixture of microcrystalline cellulose and 95.0% w/w of the total amount of L-arginine. The formulation for making the granulation has the following composition:
mg/tablet
povidone, USP (Plasdone K90)
5.0
sodium lauryl sulfate
0.3
L-arginine, USP/FCC
60.0
omeprazole, USP (micronized)
10.0
g
microcrystalline cellulose (AvicelPH102)
24.7
purified water, USP
n/a
Tabletting.
The granulation is tabletted into tablets containing 10 mg of omeprazole by first mixing the omeprazole granules with glyceryl monostearate:
omeprazole granules
100.0
mg
glyceryl monostearate (Myvaplex)
5.0
mg
sodium starch glycolate
5.0
mg
Tabletting tools: 0.2812″
target weight : 110 mg/tab
target hardness : 7 Kp
LOD of granules : less than 3%
Enteric Coating.
The tablets were coated with the same enteric coating that was applied to the tablets in Example 2.
EXAMPLE 4
Granulation.
A granulation containing omeprazole is formed in fluid bed Coater using a top spray granulation forming suspension containing omeprazole, micronized to 95% less than 15 microns, 5.0% w/w of the total amount of L-arginine, polyvinyl pyrrolidone, sodium lauryl sulfate and purified water which is sprayed onto a mixture of microcrystalline cellulose and 95.0% w/w of the total amount of L-arginine. The formulation for making the granulation has the following composition:
mg/tablet
povidone, USP (Plasdone K90)
5.88
polysorbate 80
0.60
L-arginine, USP/FCC
60.0
omeprazole, USP (micronized)
20.0
crospovidone XL
5.88
microcrystalline cellulose
25.54
purified water, USP
n/a
Tabletting.
The granulation is tabletted into tablets containing 20 mg of omeprazole by first mixing the omeprazole granules with glyceryl monostearate:
omeprazole granules
117.9
mg
glyceryl monostearate (Myvaplex)
6.1
mg
Tabletting tools: 0.2812″
target weight : 124 mg/tab
target hardness : 7 Kp
LOD of granules : less than 3%
Enteric Coating.
The tablets were coated with the same enteric coating that was applied to the tablets in Example 1.
EXAMPLE 5
The granulation of Example 1 was prepared and tabletted into tablets containing 20.0 mg of omeprazole. These tablets were coated as follows:
Enteric Coating.
An enteric coating was applied to prepare enteric coated tablets as follows:
omeprazole tablets
126.00
mg
(prepared above)
Eudragit L30D-55
17.00
mg
1M NaOH (to adjust pH to 5.0)qs
na
acetyl tributyl citrate
1.70
mg
talc
3.80
mg
polysorbate 80
1.50
mg
Purified water qs
na
The solid coating materials were dispersed in the water and this mixture was coated onto the omeprazole tablets using a perforated pan. A seal coat was applied using the procedure of Example 1.
EXAMPLE 6
In the case of a pharmaceutical formulation with a pelleted omeprazole core, the core is comprised of omeprazole, a surface active agent, a filler, an alkaline material and a binder.
Omeprazole activated pellets (sodium free) are prepared as follows: 13.650 kg of Purified water is dispensed into a suitably sized stainless steel container. L-Arginine Base (0.210 kg), Lactose Anhydrous, NF (1.75 kg) and Povidone (Plasdone® K-90) (0.056 kg) is added to the purified water while homogenizing at full speed (about 5,000 rpm). Homogenizing is continued until the materials are completely dissolved. Polysorbate 80, NF (0.044 kg) is added to the solution while homogenizing at a lower speed (700-3300 rpm) to avoid excess foaming.
The material is homogenized until dissolved completely. Half of the solution (7.855 kg) is transferred into a 5-10 gallon stainless steel container. The original container is hereafter referred to as “container A” and the new container is henceforth referred to as “container B.” Micronized omeprazole 95% less than 15 microns (0.980 kg) is added to container A while homogenizing at a lower speed (700-3300 rpm) to avoid excess foaming. The Omeprazole is allowed to disperse into the solution completely and then homogenized for another 10 minutes. The homogenizer is replaced with a mechanical stirrer and the suspension is continuously stirred throughout the coating process. When approximately three fourth of the omeprazole suspension in container A is consumed, 0.980 kg of micronized omeprazole is added to container B while homogenizing at a lower speed (700-3300) to avoid excess foaming. The Omeprazole is allowed to disperse in the solution completely and homogenization is continued for another 10 minutes. The homogenizer is replaced with a mechanical stirrer and the suspension is continuously stirred throughout the coating process. 9.98 kg of sugar spheres are added to a fluidized bed coater and preheated until the product reaches 40-45° C. The drug suspension from containers A and B are sprayed onto the spheres. The atomization pressure is between 1.5 to 3.5 bar and the pump rate is 2-100 ml/min. The spray rate does not exceed 20 ml/min in the first two hours to avoid agglomeration of the sugar spheres. The coating suspension is transferred to a smaller container to facilitate stirring when the surface of the coating suspension reaches the stirring blade. After the coating suspension has been consumed the pump is stopped and the fluidization is continued in the fluidized bed coater with the heat off until the product temperature drops below 32° C.
The pellets are then transferred to a fluidized bed coater into a 50° C. oven (45-55° C.). The pellets are dried until the moisture content of the pellets is not more then 2.5%. The pellets are separated into different size fractions by using a SWECO Separator equipped with 14 and 24 mesh screens. The pellets are collected in doubled polyethylene lined plastic containers and stored with desiccant.
Enteric Coating Process
10.844 kg of isopropyl alcohol, USP is dispensed into a suitably sized stainless steel container. 10.844 kg of acetone is added to the isopropyl alcohol. 1.683 kg of hydroxypropyl methylcellulose phthalate (Hypromellose 55, Substitution type 200731) and cetyl alcohol, NF (0.084 kg) are added to the solution while homogenizing at full speed until all the materials are dissolved completely. The homegnizer is then removed and replaced with a mechanical stirrer.
Talc (1.683 kg) is added while stirring. The talc is mixed until fully dispersed in the solution and the mixing is continued throughout the entire coating process. A fluidized bed coater is preheated to 32° C. The omeprazole active pellets (11.550 kg) are loaded into the fluidized bed coater and preheated until the temperature reaches 30° C.
The coating suspension is sprayed on the pellets using a product temperature of 25-35° C., an atomization pressure of 1.5 to 3.0 bar and a pump rate of 200-300 ml/min. The coating suspension is transferred to a smaller container to facilitate stirring when the surface of the coating suspension reaches the stirring blade.
After the coating suspension has been consumed the coated pellets are dried in a fluidized bed coater for 20 minutes using the same coating conditions except lowering the atomization pressure to 2 bars or below. The coated pellets are discharged into double polyethylene bags. The pellets are separated into different size fractions by using a SWECO separator equipped with 14 and 24 mesh screens. The pellets which are larger than 14 mesh and smaller than 24 mesh are rejected. The pellets that passed through the 14 mesh and retained on the 24 mesh are retained in polyethylene bags.
Blending
Omeprazole enteric coated pellets (Sodium Free), blended are prepared as follows:
14.400 kg of omeprazole enteric coated pellets (Sodium free) are charged, into a blender. Talc, USP (0.225 kg) is sprinkled on top of the pellet bed and then blended at 28 rpm for 5 minutes. 0.2 to 0.5 grams of each sample is withdrawn into separate vials from the blender. The blended pellets are unloaded into plastic containers lined with double polyethylene. The excess talc is screened off using a SWECO separator equipped with a 24 mesh screen. The pellets are collected in containers lined with double polyethylene bags and stored with desiccant.
Encapsulation
An encapsulation room is prepared in which the relative humidity is in the range of 35-65% and the temperature is in the range of 15-25° C. Omeprazole enteric coated pellets (Sodium Free) blended are encapsulated using the following equipment and guidelines. A capsule machine model MACOFAR MT-20 is prepared for the procedure placing the machine setting at 4, using capsule machine size part 1, capsule magazine 1. The target-filled capsule weight is 457.15 mg. If the total weight is not within 3% of the target weight, further adjustment must be performed. Capsule fill verification is performed at twenty minutes intervals on ten individual capsules. Acceptable capsules are collected in containers lined with double polyethylene bags and placed under desiccant.
While certain preferred and alternative embodiments of the invention have been set forth for purposes of disclosing the invention, modifications to the disclosed embodiments may occur to those who are skilled in the art. Accordingly, the appended claims are intended to cover all embodiments of the invention and modifications thereof which do not depart from the spirit and scope of the invention. | A stable pharmaceutical pellet formulation that employs a core containing omeprazole or a pharmaceutically acceptable salt of omeprazole and lysine or arginine. The pellet core is directly enteric coated without a separating layer being applied between the core and the enteric coating. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present methods and systems generally relate to processing and transmitting information to facilitate providing service in a telecommunications network. The methods and systems discussed herein more particularly relate to use of global satellite positioning to facilitate processing and transmission of information associated with telecommunications service locations and routing travel between more than one such service location.
2. Description of the Related Art
Efficient and effective customer service is an essential requirement for commercial enterprises to compete successfully in today's business world. In the telecommunications industry, for example, providing customer service is an important part of sustaining market share in view of the many competitors in the industry. Customers whose telephone service, for example, is interrupted or disconnected for even a relatively short period of time may desire to seek an alternative source for service, especially if the interruption or disconnection is not addressed by a quick and effective customer service response.
One important aspect of providing customer service is maintaining accurate and complete knowledge of the customer's location. Computer systems and databases that provide customer addresses often only provide vague references, however, to the exact location of the customer. Such customer addresses typically do not include information of sufficient specificity to permit efficient identification of a service location associated with the customer. In the context of a technician transporting a vehicle to a customer's service location, for example, this lack of sufficient service location information can generate excessive driving time and slow response time. Where the response time is unacceptably high, the lack of sufficient service location information can result in delayed or missed customer commitments. It can be appreciated that such delayed or missed customer commitments can cause a commercial enterprise to lose valuable customers.
What are needed, therefore, are methods and systems for acquiring information associated with a customer's service location. Such methods and systems are needed to obtain, for example, a latitude and longitude associated with the customer's service location. In one aspect, if latitude and longitude information could be collected by a service technician when the customer's service location is visited, those coordinates could then be used to find the customer at a later date. Moreover, if latitude and longitude coordinates could be made available in a database associated with that specific customer, the coordinates could be used to assist in determining the service location of that customer. Such service location information could permit a service technician to drive directly to the customer service location with little or no time lost searching for the service location.
What are also needed are methods and systems for providing a service technician with directions, such as driving directions between two or more service locations. Such directions could be employed to route travel from a first customer service location to a second customer service location. It can be seen that such directions would further reduce the possibility of error in locating a customer service location and thereby enhance customer service response time.
SUMMARY
Methods and systems are provided for obtaining information related to a customer service location. One embodiment of the method includes requesting at least one set of coordinates associated with the customer service location; accessing a technician server to direct a global satellite positioning system to obtain the set of coordinates for the customer service location; obtaining the coordinates and updating one or more databases with the coordinates. The coordinates may include at least one of a latitude and a longitude associated with the customer service location. One embodiment of a system for obtaining information related to a customer service location includes an input device configured for use by a service technician at the customer service location. A technician server is included in the system for receiving data transmissions from the input device. The technician server is in communication with a global positioning satellite system for determining a set of coordinates associated with the input device. Computer-readable media embodiments are also presented in connection with these methods-and systems.
In addition, methods and systems are discussed herein for generating directions for a service technician traveling from a first customer service location to at least a second customer service location. One embodiment of the method includes obtaining through a technician server at least one set of “from” coordinates associated with the first customer service location and at least one set of “to” coordinates associated with the second customer location; transmitting the “from” and “to” coordinates to a mapping system; and, generating directions in the mapping system based on the “to” and the “from” coordinates. One system embodiment includes an input device configured for use by a service technician at a first customer service location. A technician server is provided for receiving data transmissions from the input device. A global positioning satellite system, which is configured for determining at least one set of “from” coordinates associated with the input device is provided for use on an as needed basis. At least one database is included in the system for storing a “to” set of coordinates associated with the second customer service location and the “from” set of coordinates. The system further includes a mapping system operatively associated with the input device for generating travel directions based on the “from” and “to” coordinates. At least one of the sets of coordinates includes latitude and a longitude data. Computer-readable media embodiments of these methods and systems are also provided.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is a schematic diagram depicting one embodiment of a system for obtaining, processing, and transmitting information related to providing customer service at a customer service location;
FIG. 2 is a schematic diagram depicting a portion of the system of FIG. 1 in more detail;
FIG. 3 is a process flow diagram showing one embodiment of a method for obtaining, transmitting and processing information related to providing service at a customer service location;
FIG. 4 is a schematic diagram depicting one embodiment of a system for obtaining, processing, and transmitting information related to providing customer service at a customer service location; and,
FIG. 5 is a progress flow diagram depicting one embodiment of a method for obtaining, processing, and transmitting information related to providing customer service at a customer service location.
DETAILED DESCRIPTION
Referring now to FIGS. 1 and 2, a service technician visiting a customer service location is provided with a technician input device 2 for receiving and transmitting information related to a disruption or interruption of service at the service location. The input device 2 can be a wireless PC, for example, a laptop, a personal digital assistant (PDA), a wireless pager or any other device suitable for receiving and transmitting data associated with providing service at the customer service location. A transponder system 4 is operatively associated with the input device 2 for receiving and transmitting signals such as satellite transmission signals, for example.
The input device 2 is configured and programmed to permit the service technician to access a technician server 6 . As shown in FIG. 1, access to the technician server 6 can be enabled through a wireless data network 8 through a radio connection 10 . Access to the technician server can also be enabled by a modem connection 12 through a landline server 14 . The landline server 14 can be a server configured in accordance with a server having a CSX 7000 trade designation employed by BellSouth Telecommunications (BST—Atlanta, Ga.).
A protocol server 16 receives and processes communications from both the wireless data network 8 and the landline server 14 . In operation of the input device 2 , the protocol server 16 processes information transmitted from the input device 2 including, for example, a user ID, a password, a radio serial number, an input device serial number, and other similar data associated with a service technician and service provided at a customer service location. In one aspect, the protocol server 16 can include one or more WINDOWS NT servers (Microsoft Corporation) configured to assign one or more logical ports to transmissions received from the input device 2 .
In one aspect of the present methods and systems, the technician server 6 can be a server having a TECHACCESS trade designation (Telcordia Technologies). The technician server 6 can be a conventional server configured and programmed to verify and/or process information received from the input device 2 . The technician server 6 functions as a transaction request broker between the protocol server 16 and one or more other systems operatively connected to the technician server 6 . The systems operatively associated with the technician server 6 can include, among other possible systems, a global positioning satellite system 18 (GPS system), a dispatch system 20 , an address guide system 22 , and a customer records system 24 .
In one embodiment of the present methods and systems, the GPS system 18 can be configured in accordance with the BellSouth Telecommunications Global Positioning Satellite System (GPS) as implemented by SAIC's Wireless Systems Group (WSG). The GPS system 18 is operatively associated with the transponder system 4 and can be employed to track, dispatch, and monitor service technicians and their input devices at numerous customer service locations. In one aspect, the GPS system 18 interacts with a transponder mounted on a mobile vehicle (not shown) employed by the service technician at a customer service location.
One purpose of the GPS System 18 is to provide supervisors and managers of service technicians with more comprehensive technician activity information. The GPS system 18 can include one or more servers (not shown) and one or more databases (not shown) for transmitting, receiving and storing data associated with satellite communications. In the context of the present methods and systems, the GPS system 18 serves to acquire information associated with a customer service location including, for example, the latitude and longitude coordinates of the customer service location.
The dispatch system 20 serves to receive, process and transmit information related to service required at one or more customer service locations. In one embodiment, the dispatch system 20 includes a server, a database and one or more graphical interfaces for receiving commands from a user. Such commands can include, for example, entry on a graphical user interface (GUI) of customer information and a problem description associated with a particular interruption or disruption of service. The dispatch system 20 communicates with the technician server 6 to process and transmit information related to actions to be performed at a customer service location. Examples of dispatch systems suitable for use in connection with the present methods and systems include the “LMOS,” “IDS” and “WAFA” systems of BellSouth Telecommunications.
The address guide system 22 includes a database 26 for storing universal type address information, examples of which are shown in FIG. 2 . The address guide system 22 can be considered the keeper of all addresses in the universe of telecommunications services. The address guide system 22 helps to promote valid addresses as customer service locations. For example, if a customer contacts a telecommunications service provider, the customer can be queried for the customer's address. If the customer provides an address of 123 XYZ Street and there is no 123 XYZ Street in the database 26 of the address guide system 22 , then a correct address for the customer can be confirmed and entered into the database 26 . An example of an address guide system 22 suitable for use in accordance with the present methods and systems is the “RSAG” application of BellSouth Telecommunications.
The customer record system 24 is operatively connected to the address guide system 22 and includes a database 28 for storing customer related information, examples of which are shown in FIG. 2 . In one embodiment of the present methods and systems, the customer record system 24 serves to store information related to a particular service location and customer. For example, when telephone service is initially requested by a customer, a record in the database 28 can be populated with information that will create a correspondence between the customer's address and the details of the telephone service to be installed. Records in the database 28 of the customer record system 24 typically remain effective as long as service at a particular address remains the same for that customer. The customer record system 24 interfaces with the dispatch system 20 during the operation of the dispatch system 20 to generate work orders associated with service issues at customer service locations. For example, if problems arise with a customer's service, such as the initial installation order for that service, the dispatch system 20 schedules the work order. The dispatch system 20 draws on information contained in the customer record system 24 to create the dispatch order for a service technician to perform any actions required by the work order.
Referring now to FIGS. 1 through 3, an operative example of the present methods and systems include a service technician at a customer service location with an input device 2 . In accordance with the connections described above, in step 32 the technician server 6 can request the coordinates, in terms of latitude and longitude, from the service technician at the customer service location. The request of step 32 can be performed, for example, in step 34 by a job closeout script application of the technician server 6 that is adapted to query the service technician regarding the customer's location at the conclusion of a service call. The technician server 6 may check to determine whether a latitude and longitude are already present in the customer's information in the database 28 of the customer record system 24 .
The technician server 6 can then instruct the service technician in step 35 to verify his presence at the customer service location. In step 36 , the GPS system 18 is accessed, such as through a “Fleet Optimizer” application (BellSouth Technologies) associated with the technician server 6 , to obtain latitude and longitude coordinates derived from the location of the service technician's input device 2 . In step 38 , the GPS system 18 transmits a signal to the transponder system 4 operatively associated with the input device 2 and obtains coordinates of the customer service location in step 40 . The GPS system transmits the obtained coordinates to the technician server 6 in step 42 . In step 44 , the dispatch system 20 is updated with the newly obtained latitude and longitude information. In step 46 , the database 28 of the customer records system 24 is updated to reflect this latitude and longitude information. In step 48 , the latitude and longitude information is transmitted to and stored in the database 26 associated with the address guide system 22 .
It can be seen that just because one has a street address for a customer service location, it does not necessarily follow that locating the customer service location can be readily performed. For example, a street address in Pittsburgh, Pa. might be Three Rivers Stadium Park. If this is the only information available, however, it may be difficult to find the customer service location where work needs to be performed. Use of a GPS system to associate coordinates with a street address permits one to know the position of a customer service location, and hence the location of a service technician performing work at that customer service location.
In another example of the present methods and systems, a new customer requests service installation at ABC Street. Verification is performed to determine that ABC Street is a valid address. If it is a valid address, and if latitude and longitude information has been populated in the address guide system 22 , then the information can be used effectively by a service technician to address the customer's needs. In addition, if a service issue later arises with the customer service location, the dispatch system 20 can obtain the customer record, including the customer name, contact number, the type of facilities the customer has, and latitude and longitude information associated with the customer service location. This complete record of information provides enhanced response time for addressing the customer's service needs.
Referring now to FIGS. 4 and 5, in another aspect of the present methods and systems, a mapping system 52 can be provided for routing travel of a service technician between more than one customer service location. The mapping system 52 is configured and programmed to provide travel or routing directions to a service technician from a first location to at least a second location where customer service is to be performed. The mapping system 52 can include conventional mapping software installed on a computer-readable medium operatively associated with the input device. The mapping system 52 can also be accessed remotely, such as through a wireless connection between the mapping system 52 and the input device 2 .
In one embodiment, the technician server 6 functions to provide latitude and longitude information to the mapping system 52 . This information includes “from” information (i.e., the origin customer service location of the service technician) and “to” information (i.e., the destination customer service location to where travel is desired for the service technician). Before dispatch to the next customer service location, the service technician requests driving instructions in step 62 . The technician server 6 queries the “Fleet Optimizer” application, or its functional equivalent, in step 64 to obtain the current customer service location in step 66 , which can be used by the mapping system 52 as the “from” location. If necessary, and in accordance with previous discussion of the present methods and systems, the GPS system 18 can be accessed to obtain “from” latitude and longitude coordinates in step 68 .
The address guide system 22 can then be accessed by the technician server 6 in step 70 to provide the “to” location to the mapping system 52 , including latitude and longitude information for the destination customer service location. In step 72 , the technician server 6 transmits the “from” and “to” coordinates to the technician input device 2 . In step 74 , the mapping system 52 processes the “from” and “to” coordinates. The mapping system 52 can then generate and output driving directions from the “from” location to the “to” location for the service technician in step 76 . It can be appreciated that the output of the mapping system 52 including the driving directions can be in any conventional format suitable for communicating the directions to the service technician. For example, the output including the driving directions can be in electronic format or hard copy format.
As discussed above, accurate latitude and longitude coordinates may have already been established for the present or origin customer service location. In the process of dispatching a service technician to a next customer service location, however, it may be necessary to engage the GPS system 18 to obtain these latitude and longitude coordinates. The GPS system 18 can therefore be employed to provide knowledge of one or more service technician locations for various customer service locations where service is required. The GPS system 18 also functions to promote providing correct customer service location information, including latitude and longitude coordinates associated with customer addresses and/or associated critical equipment. It can be seen that algorithms can be applied in the dispatch system 20 and/or the technician server 6 to use this knowledge of service technician whereabouts and customer service locations to facilitate moving the next best or available service technician to the next highest priority or most appropriate service location.
The term “computer-readable medium” is defined herein as understood by those skilled in the art. A computer-readable medium can include, for example, memory devices such as diskettes, compact discs of both read-only and writeable varieties, optical disk drives, and hard disk drives. A computer-readable medium can also include memory storage that can be physical, virtual, permanent, temporary, semi-permanent and/or semi-temporary. A computer-readable medium can further include one or more data signals transmitted on one or more carrier waves.
It can be appreciated that, in some embodiments of the present methods and systems disclosed herein, a single component can be replaced by multiple components, and multiple components replaced by a single component, to perform a given function. Except where such substitution would not be operative to practice the present methods and systems, such substitution is within the scope of the present invention.
Examples presented herein are intended to illustrate potential implementations of the present communication method and system embodiments. It can be appreciated that such examples are intended primarily for purposes of illustration. No particular aspect or aspects of the example method and system embodiments, described herein are intended to limit the scope of the present invention.
Whereas particular embodiments of the invention have been described herein for the purpose of illustrating the invention and not for the purpose of limiting the same, it can be appreciated by those of ordinary skill in the art that numerous variations of the details, materials and arrangement of parts may be made within the principle and scope of the invention without departing from the invention as described in the appended claims. | Methods and systems are provided for obtaining information related to a customer service location and directions for routing a service technician from one customer service location to another. One embodiment includes requesting at least one set of coordinates associated with the customer service location; accessing a technician server to direct a global satellite positioning system to obtain the set of coordinates for the customer service location; obtaining the coordinates and updating one or more databases with said coordinates. The coordinates may include at least one of a latitude and a longitude associated with the customer service location. Another embodiment includes obtaining through a technician server at least one set of “from” coordinates associated with the first customer service location and at least one set of “to” coordinates associated with the second customer location; transmitting the “from” and “to” coordinates to a mapping system; and, generating directions in the mapping system based on the “to” and “from” coordinates. At least one of the sets of coordinates includes latitude and longitude data. System and computer-readable media embodiments of these methods are also provided. | 6 |
SUMMARY OF THE INVENTION
This invention relates to improvements in a donation box of the type employed to solicit and receive donations, as in behalf of charitable organizations. Such boxes are commonly used to receive donations and to provide means to display and make available candy and other merchandise as partial compensation for a donation. Such boxes are usually displayed in retail establishments or other places frequented by the public in readily accessable locations, and usually receive coins as donations.
The primary object of the invention is to provide a construction of a donation box which is quickly converted between closed and open positions and into which candy and other merchandise can be filed for convenient and transportable condition when closed, and which exposes the candy or other contained items and the coin receiving slot when open.
A further object is to provide a donation box in which a coin receptacle is removable and is inserted in the manner which resists pilferage thereof by concealing the access means thereto from would-be pilferers.
A further object is to provide a donation box which has interfitting parts of a nature which reenforces the construction thereof, exposes data identifying the organization soliciting donations, and which is strong, of light weight, which provides convenience to persons making donations and makes available to such persons candy or other merchandise which a donator can easily reach while making a donation.
Other objects will be apparent from the following specifications.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the donation box in open or use condition.
FIG. 2 is a perspective view of the donation box in its closed or storage position.
FIG. 3 is a perspective view of a removably mounted donation receptable carried by the donation box.
FIG. 4 is a longitudinal vertical sectional view of the donation box taken on line 4--4 of FIG. 1 and illustrating the box in its open or use condition.
FIG. 5 is a transverse sectional view taken on line 5--5 of FIG. 1.
FIG. 6 is a horizontal sectional view taken on line 6--6 of FIG. 4.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the drawings, the box 10, which preferably may be formed of paper board or corrugated paper board or plastic material of semi-rigid nature, is characterized by a bottom panel 12, side panels 14, end panels 16 and a top panel 18. Top panel 18 is preferably formed integrally with one end panel 16 and is provided with a crease at 19 to accommodate selected position thereof as between the vertical open position illustrated in FIGS. 1 and 4 and the horizontal closed position thereof illustrated in FIG. 2. The panel 18 is also provided with a crease 20 to facilitate selected position thereof as between the closed position illustrated FIG. 2 and the open position illustrated in FIGS. 1 and 4. The free end portion 22 of top panel 18 is preferably of slightly less width than the remaining portion thereof to accommodate insertion thereof between the side walls 14 when the box is in its open position illustrated in FIGS. 1 and 4, or insertion thereof into the box as seen in its closed position of FIG. 2. The opposite side walls 14 are characterized by downwardly inturned wall portions 24, which extend for a portion of the length thereof and to the end wall 16 from which the top panel 18 projects. The end panel 16 from which the top panel 18 projects may include and have folded therefrom supplemental side panels 26 adapted to bear against the inner surfaces of the respective side walls 14 and to be confined in contact with the sides 14 by the inturned side panels 24.
The end panel 16 shown at the right in FIGS. 1 and 2, has formed integral therewith and folded therefrom the top panel 30 of a donation box receiver chamber, which is characterized by a coin receiving slot 32. The coin receiving chamber is completed by a downturned panel 34 and the box sides 14 and bottom 12. Supplemental side panels 36 project from opposite sides of the downturned panel 34 and bear against the inner surfaces of the side panels 14, as best seen in FIG. 6, while being confined in that position by the inturned side panels 24. If desired, the top panel 18 may terminate in a downturned flange, not shown, to facilitate maintenance of the panel 18 in closed position illustrated in FIG. 2. Spaced partitions 38 may be secured to the box end 16 within the chamber defined by top panel 30, side and end walls 16, bottom 12 and panel 34 to form guides in the event coin receptacle 40 is of a dimension less than width of the box 10.
The coin receptacle 40 may be of the construction illustrated in FIG. 3. Receptacle 40 is preferably formed of paper board, corrugated board or plastic sheet material and is characterized by a top 42 having an opening 44 therein, preferably slightly larger than and adapted to register with the coin slot 32 when the coin receptacle is in operative position while the box is closed. The coin receptacle also includes end walls 46, side walls 48, and 52, and bottom 50. Wall 48 may be free to swing between an open position as seen in FIG. 3 and a closed position when operatively positioned within the box. Wall 48 may have side flanges 54 which may be inserted into the coin receptacle when the receptacle is closed, and may include an end flange 56 to overlie the bottom panel 50 when the coin receptacle is closed. The coin receptacle may be positioned within the box as shown in FIG. 4 with its wall 48 bearing against the adjacent end wall 16 of the container, or may be reversed to bear against the panel 34.
When the box is assembled and is open as shown in FIGS. 1 and 4 and contains candy or other merchandise, the parts of the box are substantially self-locking, and the coin receptacle is fully confined and effectively retained. Thus the candy or contents in the container, when fully or partially filling the container, hold in place effectively the top panel 18 in its vertical position, the inturned side panels 24 and the flanges 36 of panel 34. The coin slot 32 will be of a size to limit access for pilfering purposes so as to retain the coins collected within the coin receptacle.
Access to the compartment containing the coin receptacle is normally limited to a condition in which candy or other merchandise is removed so as to permit the cover panel 18 to be released from its vertical position seen in FIGS. 1 and 4. Release of the cover from operative FIG. 1 position permits the inturned side panels 24 to be swung out of the container to a substantially vertical position at which the supplemental panels 36 are released so that the panel 34 of the receptacle-receiving compartment may be swung open to provide access to the receptacle 40 and removal of the receptacle from the container. Alternatively, assuming that the wall 48 of the coin receptacle is positioned adjacent to panel 34 of the receptacle compartment, the receptacle wall 48 may be swung to open position illustrated in FIG. 3 to facilitate removal of coins from the receptacle. If desired, access openings 58 may be formed in wall 48 and flange 56 of the receptacle to facilitate manual manipulation of the wall 48 from its closed position to its open position illustrated in FIG. 3.
From the foregoing it will be seen that the container provides concealed enclosure of a coin receptacle into which coins may be easily applied and from which coins may not normally be removed. While in condition for use the contents of the box, such as candy or other merchandise, hold the component parts of the box in operative position in which the various parts interfit and reenforce each other. An observer of the construction, while in its normal open position containing candy or other merchandise, cannot observe the manipulation of the respective parts required to open the box and its coin receptacle compartment. At the same time the construction is such that no latching or closing means separate from the components of the box need be provided. Also, the knowledgeable persons who service the box to supply candy and merchandise thereto, and to collect coins therein, can open the coin receptacle compartment quickly and easily so that the time required to service the box and to collect coins deposited therein is minimal.
While the preferred construction of the box has been illustrated and described, it will understood that changes in the construction may be made within the scope of the appended claims without departing from the spirit of the invention. | A donation box having a collection receptacle receiving chamber and a merchandise compartment, wherein the constituent panels are interengaged in assembled form in a manner which permits merchandise in its compartment to maintain the box parts interengaged. | 0 |
The present invention generally relates to an apparatus and a method for communicating parameters relating to down-hole conditions to the surface. More specifically, it pertains to such an apparatus and method for communication using an optical fiber.
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefits of priority from Application Number 0524827.3, entitled “BOREHOLE TELEMETRY SYSTEM,” filed in the United Kingdom on Dec. 6, 2005, and which is commonly assigned to assignee of the present invention and hereby incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
One of the more difficult problems associated with any borehole is to communicate measured data between one or more locations down a borehole and the surface, or between down-hole locations themselves. For example, communication is desired by the oil industry to retrieve, at the surface, data generated down-hole during operations such as perforating, fracturing, and drill stem or well testing; and during production operations such as reservoir evaluation testing, pressure and temperature monitoring. Communication is also desired to transmit intelligence from the surface to down-hole tools or instruments to effect, control or modify operations or parameters.
Accurate and reliable down-hole communication is particularly important when complex data comprising a set of measurements or instructions is to be communicated, i.e., when more than a single measurement or a simple trigger signal has to be communicated. For the transmission of complex data it is often desirable to communicate encoded digital signals.
Widely considered for borehole communication is to use a direct wire connection between the surface and the down-hole location(s). Communication then can be made via electrical signal through the wire. While much effort has been spent on “wireline” communication, its inherent high telemetry rate is not always needed and very often does not justify its high cost.
Another borehole communication technique that has been explored is the transmission of acoustic waves. Whereas in some cases the pipes and tubing within the well can be used to transmit acoustic waves, commercially available systems utilize the various liquids within a borehole as the transmission medium. Examples of the use of hydraulic lines for downhole power generation and telemetry are described in WO 2004/085796 A1 and WO 2005/024177 A1.
Yet another borehole communication system is based on optical signals. Communication over an optical fiber is accomplished by using an optical transmitter to generate and transmit laser light pulses that are communicated through the optical fiber. Downhole components can be coupled to the optical fiber to enable communication between the downhole components and surface equipment. Examples of such downhole components include sensors, gauges, or other measurement devices.
Typically, an optical fiber is deployed by inserting the optical fiber into a control line, such as a steel control line, that is run along the length of other tubing (e.g., production tubing). The control line is provided as part of a production string that is extended into the wellbore.
As described for example in the published United Kingdom patent application GB 2409871 A, optical fibers can also be applied to intervention, remedial, or investigative tools as being deployed by a wireline, slickline, coiled tubing, or some other type of conveyance structure.
Further uses of optical fibers for communication inside a wellbore are described in the related U.S. Pat. Nos. 5,898,517, 5,808,779 and 5,675,674, which describe an optical fiber modulation and demodulation system using Bragg gratings and piezoelectric crystal combination.
However, a major limitation of conventional optical communications systems applied to hostile environments such as hydrocarbon production wells is the need to terminate the fiber at each node of the communication system. The termination might be accomplished by connecting the optical cable to the communication node, which involves expensive parts and lengthy procedures to ensure that the connection is hermetically sealed against the ingress of the downhole fluids. Alternatively, special optical connectors might be used that are suitable for the hostile environment; however these are expensive. In both cases these connections, whether spliced or connectorised are expensive and create a weak point that could degrade the overall reliability of the communications system.
Outside the technical field of borehole telemetry, Berwick M. and al. describe a magnetometer in their paper: “Alternating-current measurement and non-invasive data ring utilizing the Faraday effect in a closed-loop fiber magnetometer” Optics Letters Vol. 12. No. 4, 1987. Berwick M. and al. also propose to use the system as data ring. Similar methods and apparatus can be found in the U.S. Pat. Nos. 6,462,856 B1 and 4,996,692.
It is therefore an object of the present invention to provide optical fiber based communication system that overcomes the limitations of existing devices to allow the communication of data into one or more nodes along the fiber without breaking into the fiber. The system provided is particularly for hostile environment where the fiber is enclosed in a protective tube or sheath. An example suitable for the invention could be the communication between a down-hole location and a surface location.
SUMMARY OF THE INVENTION
In accordance with a first aspect of the invention, there is provided a telemetry apparatus and method for communicating digital data from a down-hole location through a wellbore to the surface. The apparatus or methods includes a light source; an optical fiber being placed along the length of the wellbore and receiving light from the light source, wherein the optical fiber is surrounded by a protective hull; one or more transducers located to modulate optical properties of the optical fiber interacting with the fiber so as to impart information onto the fiber without breaking into the protective hull at the downhole location; one or more sensors for measuring down-hole conditions and/or parameters; a controller to provide a modulated signal to the transducer, said modulated signal being under operating conditions representative of measurements by the one or more sensors; and an optical detector adapted to detect changes in the properties of light passing through the fiber.
It is another aspect of the invention to provide apparatus and methods for modulating any one or any combination of these properties of the light traveling through the fiber without penetrating the fiber or interrupting its physical integrity of an protective hull, sheath or tube encapsulating the fiber at the point where the modulation is applied. Hence no mechanical element of the transducer extends into or beyond the boundary defined by the hull.
In a variant of the invention the fiber and the modulating transducer are separated without direct mechanical contact. In a preferred embodiment of this variant of the invention the modulating transducer modulates the light properties through a protective sheath or tube that seals the tube from the environment without using or causing a perforation in the protective sheath or tube at the location of modulation. Thus, the fiber can be installed separately from the transducer.
The transducer is preferably a magnetic field generator and even more preferably a solenoid wound around the optical fiber or its protective sheath or tube such that the fiber is preferably guided through the core area of the solenoid.
The invention includes the variant of having several such transducers placed along the length of the fiber thus creating a plurality of communication nodes where data and information can be fed into the fiber.
The light transmitted through the fiber is preferably in a defined known polarization state, and more preferably linear polarized. In operation the transducer may then changes a polarization state of the light passing through the fiber. In a variant of this embodiment, the invention is making use of the Faraday effect.
In another variant of the invention, the transducer changes the amplitude, phase or frequency of the light preferably by causing a mechanical force to act on the fiber. The section of fiber that is affected by the transducer might also be modulated in its optical path length, the change being detectable preferably by interferometric means.
To enhance the effect of the transducer on the fiber, it is preferably at least partially coated with hetero-material designed to respond specifically to the force generated by the transducer. For example a magnetostrictive material may be used in the case of a magnetic field and a, preferably polymeric, piezo-electric coating in case of an electrical field. Heat can also be used as a force field with temperature induced changes of the optical properties of the fiber being registered at the surface.
In yet another variant, information is conveyed to the fiber by means of acoustic waves that modulate the local refractive index of optical fiber via the stress-optical effect and thus modulate the optical path length of the fiber. Such changes in the optical path length can be converted to measurable changes in the light, for example by interferometric techniques.
Still another variant involves applying an electric field across the fiber and modulating its refractive index through the electro-optic effect; the Kerr effect applies to all fibers and responds to the square of the electric field; specially poled fibers are responsive linearly to the electric field through the Pockels effect.
While the apparatus of the invention can be attached directly to casing or production tubing, it is regarded as a preferable placement method to guide the optical fiber through a control line attached to the production tubing with the transducer or transducers being placed such that the optical fiber inside the control line is within the force field.
The optical fiber may either form a loop from a wellhead to the downhole location and returning back to the wellhead to guide light from the source to the detector or may be terminated in the borehole with a mirror.
It is further seen as advantageous to compensate for ambient drifts in the detector signal through the use of a control loop preferably placed at surface. This control loop may include a modulator to change the polarization of light passing through the fiber.
The invention further contemplates the use of a downhole power source to provide a current for the magnetic field generator. If a battery or battery pack is not suitable, the power source can be a generator converting for example pressure fluctuation, temperature gradients or vibrations of tubing into electrical power.
These and other aspects of the invention will be apparent from the following detailed description of non-limitative examples and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates elements of an optical fiber telemetry system for a wellbore in accordance with an example of the invention;
FIG. 2A shows details of an embodiment of the invention using a magnet field;
FIG. 2B shows details of a variant of the invention as shown in FIG. 2A ;
FIG. 3 shows a signal generated using a method in accordance with an example of the invention;
FIG. 4 schematically illustrates another embodiment of the invention; and
FIG. 5A , B schematically illustrate another embodiment of the invention using a pressure field.
DETAILED DESCRIPTION
In a first example, the light propagating through an optical fiber is assumed to be polarized. The state of polarization at any location inside the fiber refers to the variation of the electric field vector E of the propagating light as a function of time. The most general polarization state is the elliptical polarization, but in the present example the light is assumed to be linear polarized. For a definition of the polarization state the electric field vector can be decomposed into the superposition of two orthogonal fields. When the phase between the two vectors is 0 or π, the extremity of the electric field vector describes a line. The light is thus polarized linearly.
When light propagates through a given medium, the state of polarization can change and the material is then classified as birefringent. For example, in the case of a circularly birefringent material, the linearly polarized light is strongly affected, whilst the circularly polarized light is unchanged in its state of polarization, although its velocity is dependent on whether the light is left- or right-hand circularly polarized
The Faraday effect, which is known as such, is the induction of circular birefringence in some materials by the application of a magnetic field. The circular birefringence induced in the fiber rotates the polarization azimuth by an angle θ. The amount of rotation is expressed in terms of the Verdet coefficient V, which depends on the solid-state properties of the material, its temperature and the wavelength of the propagating light:
θ=∫ 0 l V{right arrow over (H)}·d{right arrow over (l)}, [1]
where the integration is carried out over the length of fiber exposed to the external magnetic field, H.
Therefore if the magnetic field is generated by a long solenoid carrying a current I wrapped N times around the fiber (ignoring ending effect), the expression of the angle of rotation can be approximated by:
θ=VNI [2]
This is the physical effect used for Faraday magnetometers. To detect the variation of θ, in the polarization azimuth, a polarization analyzer is used.
It was found that the above-described Faraday effect can be advantageously used for the purpose of this invention to transmit signals from a location inside a wellbore to a surface location.
In FIG. 1 there is shown the schematics of a wellbore 10 . The wellbore 10 is lined with casing tubes 11 . The lower part of the wellbore is shown with perforations 12 allowing the entry of produced fluids into the wellbore. The top of the wellbore terminates in a wellhead 13 .
Inside the wellbore 10 there is shown part of a production tube 14 to convey produced fluids to the surface. The perforated section of the wellbore 10 is isolated from the remaining sections of the wellbore by a packer 15 . Installed alongside the production tubing 14 is a (hydraulic) control line 16 .
The control line is used to place an optical fiber 17 into the well using for examples fluid drag methods as disclosed in U.S. Pat. No. Re 37,283, which patent is incorporated herein by reference. The fiber 17 used in the example is a mono-mode or single-mode fiber known per se.
The example of FIG. 1 further shows a solenoid 18 surrounding the control line 16 , a module 19 including a power generator and a controller to control the feeding current for the solenoid 18 .
The power generator can be a suitable battery if communication is required only for a limited period of time. Otherwise the present invention contemplates the use of downhole power generators powered for example through the hydraulic line 16 . Details of such power generators are for example described in the above referenced international patent application WO 2005/024177 A1, incorporated herein by reference for all purposes.
The module 19 is also connected to sensors 20 which are adapted to measure parameter or downhole conditions such as pressure, temperature, chemical composition, fluid properties, flow conditions and flow components or the state of downhole components, such as control valves, packers and so on. On the surface there is shown further modules 21 designed to project light into the fiber and control and measure the characteristics of the light which passed through the fiber. Details of the surface equipment 21 are shown in FIGS. 2A and 2B .
To the left side of FIG. 2A there is shown a light source, e.g. a laser diode 22 . The light emitted by the light source is polarized using a polarizer 221 and projected into the optical fiber 17 using a suitable method, which could be a lens 222 as shown.
Light thus fed into the fiber 17 forms a loop that at a downhole location passed through the core of the solenoid 18 and returns to the surface.
At the surface the light enters a beam-splitter 23 through lens 231 . The two beams of light emerging from the beam-splitter are each guided through polarization filters 241 , 242 and respective photodetectors 243 , 244 . The output of the photodetectors 243 , 244 is connected to a feedback unit 25 that computes the variation of θ as described above. The feedback unit provides also a controlled amount of current to the compensation solenoid 26 that steers the polarization mode such that the output of the polarization filters 241 , 242 is set in accordance with the quadrature condition to be explained in further detail below.
In operation the analogue signal of the down-hole sensor 20 is digitized inside the control module 19 . An amplitude, frequency, or phase modulated current corresponding to the obtained data sequence is then applied to the solenoid 18 through which the optical fiber passes axially. This external variation in magnetic field varies the polarization azimuth, θ of the propagating light via the Faraday effect. This change in θ is then detected at the surface via the polarization analyzer 21 . The output signal is then demodulated via an amplitude or phase demodulation algorithm as appropriate.
In the polarization analyzer 21 , the output light beam goes through the polarizers 241 , 242 oriented at ±45° with respect to the input light beam polarization axis, followed by the photo-detectors 243 , 244 . The signal power at each detector is therefore given by:
P=P o (1±cos 2(θ+θ 0 )), [3]
where θ 0 is the offset angle between the original polarization axis and the polarization azimuth of the output beam without any external magnetic field. The offset value θ 0 is due to the internal birefringence of the fiber and the temperature gradient inside the wellbore. This offset value and the Verdet coefficients are both temperature dependent and will drift. It is therefore difficult to measure absolute variation in θ. Alternatively the functions of 23 , 241 and 242 can be combined in a polarizing beamsplitter, such as a Wollaston prism
However when following the above set-up the two photo-detector outputs are arranged in antiphase:
i 1 =P 1 (1+cos 2(θ+θ 0 ))
i 2 =P 2 (1−cos 2(θ+θ 0 )), [4]
where θ 0 , P 1 , P 2 are constant. The signals i 1 and i 2 can be recombined differentially and by adjusting the gains a new output is obtained:
i 0 ≈cos 2(θ+θ 0 ). [5]
This system response is most sensitive at:
2(θ+θ 0 )=π/4+2 nπ [6]
This is the so-called quadrature condition.
In an ideal system, before the start of data transmission (but with light propagating in the fiber 17 ), the polarization analyzers are set to satisfy the quadrature condition. However the drift in the offset phase prevents the system from staying at the optimal quadrature condition. Therefore an integration feedback loop using the second coil 26 at the surface is used to restore the quadrature conditions. It will be appreciated that the solenoid can be replaced by any other method known to change the polarization of the light beam such as Lefevre loops, mechanical manipulation (squeezing, twisting) and electro-optical modulation.
To overcome for example linear birefringence induced by bending in the fiber, the fiber may be twisted. Introducing a twist rate onto an optical fiber is known to induce a fixed circular birefringence that annihilates the unwanted linear birefringence effect. Further methods to improve the output may include annealing the fiber.
The above example can be modified to include more fiber-based optical components to eliminate bulk optical components referred to.
In the example of FIG. 2B the laser source used is either a distributed feedback or DFB semiconductor laser or a superluminescent light-emitting or SLD/SLED semiconductor laser diode 22 . The DFB laser has very narrow optical bandwidth (<1 MHz) and it is highly polarized optical source with polarization maintaining fiber pigtail. The SLED source has very wide optical bandwidth (>35 nm) and it has single mode fiber pigtail. The output optical power is about 10 mW for both devices.
In order to eliminate any return signal, an optical isolator 222 with a polarization-maintaining fiber pigtail is introduced into the optical circuit. The SPFI-SS device offered by Micro-Optics Inc of Hackettstown, N.J., USA is, an example of a suitable device.
To increase the polarization extinction ratio from the optical source, a fiber pigtailed polarizer 223 may be used. It has a single mode or polarization-maintaining fiber at its input and polarization maintaining fiber at its output. For example, a fiber side-polished type of polarizer may be used and its polarization extinction ratio is about 23 dB. Alternatively, devices based metal inserts in the fiber or coiled birefringent fiber may be used. In certain instances, isolator 222 also incorporates a polarizer function. The plarizer 223 is set to generate linear polarized at 45° from the principal axes of 224 . In the case of an all fiber system, this may be accomplished by splicing the output fiber of the polarizer to the input of the coupler 224 such the principal axes of these two fibers are rotated at 45° from each other
A special polarization maintaining fiber coupler 224 (a suitable device is one from the PMC-IL-1×2 family provided by Micro-Optics Inc.) is used here. It is based on thin film technology and the polarization extinction ratio is designed to be higher than 23 dB at both its fast and slow axes. The conventional fused-taper polarization maintaining fiber coupler could be used as an alternative with slightly lower performance (specifically, it cannot provide the same splitting ration on both polarization axes).
Behind the coupler 224 the light enters into the fiber 17 and passes through the core of the solenoid 18 . The fiber is terminated at the remote end by a Faraday rotate mirror 225 . The remote end of the fiber can be sited down the well, or brought up to the surface in a looped control line as described in the previous example.
The Faraday rotate mirror 225 is single mode fiber pigtailed and spliced to the normal single mode fiber 17 . At room temperature it will make polarization state change of 90° against its input. The actual state change is however a function of temperature and operating wavelength. The mirror has a relatively narrow optical bandwidth (<20 nm) and also its operating temperature range is quite small (±5° C.). It may be replaced by similar mirrors such as a fiber mirror or a fiber Bragg grating.
The polarization beam combiner 232 is also a fiber component based on thin film technology and it divides the x- and y-polarization components into the separate output arms. A suitable device is, for example, one of the PDM-I1 family supplied by Micro-Optics Inc. The output of both arms is captured using sensitive photo-detectors such as 10 MHz adjustable-bandwidth balanced photo-receivers available as Model 2117 supplied by New Focus Inc.
The 45°-angle splicing between two polarization-maintaining fibers creates two orthogonal linear polarization components along its fast- and slow-axis. Both of them are launching into the PM coupler 224 and propagate along the single mode down-lead fiber 17 . The polarization state will change along the single mode fiber, however the returned optical signal will trace back along its original path with rotating 90°-angle after it reflected from the Faraday rotate mirror. Therefore the x- and y-polarization components swap the position after re-entering the PM coupler 224 .
The result of a test of the system of FIG. 2B is shown in the FIG. 3 , using a 2 km coiled fiber and a 1800 turn electro-magnetic coil and a commercially available polarization controller for adjustment of the polarization state. The wire diameter is 0.56 mm, the length is 200 m and the resistance is measured as 16Ω. The average coil diameter is about 35 mm and sensing fiber length is about 53 mm. Applying a 160 Hz modulation frequency to the coil with a driving current of 0.45 A peak current resulted in the shown single-shot measurement recorded with no further averaging. The gain of the balanced receivers has been set to 3×10 4 and the band-pass filter is set from 10 Hz to 1 kHz. In this experiment, the source power at the input to the isolator is 0.75 mW and that reaching each input to the balanced receivers is 7 μW. In further tests, it was found that readily detectable modulation on the optical signal was achieved with an electrical input to the coil below 35 mW.
It was found that the magnetic signals were transmitted through a stainless steel control line without significant effect on the modulation depth.
The variations in a magnetic field or its gradient can also be sensed with an optical fiber by using the induced dimensional change (i.e. strain) in a magneto-strictive element bonded to the fiber. This induced strain forces some light out of the fiber and thus results in a decrease in light intensity. This light intensity can then be modulated according to a recorded digital sequence to transmit data on the optical fiber. At the surface, the light intensity can be monitored by a photo detector.
In this example of the invention, as illustrated in FIG. 4 an optical fiber 41 is locally coated with a layer 411 of magneto-strictive material. In operation this part of the fiber 41 is located downhole in the solenoid 42 similar to the apparatus described above. Permanent magnets 421 , 422 are located at each end of the solenoid 42 . The magnets are used to indicate an accurate placement of the coated part of the fiber 41 in the solenoid: A first change in the light intensity is registered as the magneto-strictively coated fiber 41 passes the first permanent magnet 421 . When the coated part of the fiber exits the solenoid 42 and passes the second permanent magnet 422 a second modulation can be registered at the surface, thus indicating the accurate placement.
In operation the current through the solenoid 42 will be controlled as described above. However, in this embodiment changes in the magnetic field created by the solenoid are translated into a mechanical force on the fiber and thus into a modulation of the light intensity, which is monitored (and demodulated at the surface).
In a further variant of the invention, as shown in FIG. 5A the fiber 51 - or a downhole section of the fiber, is formed into an interferometer, for example by providing a least two partial reflectors 511 , 512 along its length. Any modulation of the optical length between a reflector pair may be read by a remote interferometer (not shown) which can conveniently be sited at surface. Fibers incorporating reflectors can be formed without significant changes in the external dimensions of the coated fiber, for example, by inscribing gratings 511 , 512 into the fiber 51 . The spacing between reflectors 511 , 512 may be selected to ensure that just one, or several transducer modules 52 are located between the reflectors. The transducer 52 mounted on the outside of a protective tube 53 which is turn is attached to a production tubing 54 . The transducer 52 is a piezo-electric transducer using an acoustic horn 521 generating acoustic waves 522 which travel through the protective tube 53 and induces a pressure change inside which is largest in the region between the gratings 511 , 512 . The acoustic wave generated by the sonic transducer 52 affixed to the control line 53 is focused by the horn 521 inside the control line where the fiber resides. The pressure induces a corresponding change of the optical path length L to L+ΔL between the second pair of gratings as schematically illustrated in FIG. 5B . Optical fiber has a small, but detectable sensitivity to hydrostatic pressure and the sensitivity of the interferometric detection system is sufficient for communications purposes.
The interrogation technique as illustrated in FIG. 5B is described in greater detail but for other purposes by Dakin and Wade in Patent GB2126820 fully incorporated herein by reference.
If more than one pair of reflectors exists, then each can be interrogated individually with minimal cross-talk. The inventors have interrogated arrays incorporating some 40 reflector pairs with better than 1:1000 cross-talk between any element in the array. Given that further multiplexing of such arrays is possible using reflectors optimised for different optical wavelengths, it will be seen that the number of nodes of such a system is essentially unlimited.
Based on the above description, it will be appreciated by a skilled person that any of the above effects which modulate the optical distance between the reflectors in a pair may be used either alone or in combination with other such methods to impart information onto the fiber.
Special coatings can be applied to the fiber to enhance the sensitivity of the fiber to an exposure to acoustic, magnetic or electric waves or fields such as the above-mentioned magneto-strictive coatings or piezo-electric coatings in the case of electric fields. In the case of electric fields, it is also desirable to include in the control line which is generally metallic with a non-conductive section, which in turn can be placed in the electric field generated by a capacitor or dipole. The main direction the electrical field may be parallel or perpendicular to the axis of the optical fiber.
While the invention has been described in conjunction with the exemplary embodiments described above, many equivalent modifications and variations will be apparent to those skilled in the art when given this disclosure. Accordingly, the exemplary embodiments of the invention set forth above are considered to be illustrative and not limiting. Various changes to the described embodiments may be made without departing from the spirit and scope of the invention, for example a temperature gradient may be used as the force field described above. Changes of the temperature modulate the optical properties across the protective hull and can be registered as signal on the surface. | A telemetry apparatus and method for communicating data from a down-hole location through a borehole to the surface is described including a light source, an optical fiber being placed along the length of the wellbore and receiving light from the light source, a transducer located such as to produce a force field (e.g. a magnetic field) across the optical fiber and its protective hull without mechanical penetration of the hull at the down-hole location, one or more sensors for measuring down-hole conditions and/or parameters, a controller to provide a modulated signal to the magnetic field generator, said modulated signal being under operating conditions representative of measurements by the one or more sensors, and an optical detector adapted to detect changes in the light intensity or polarization of light passing through the fiber. | 4 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a National Stage of International Application No. PCT/JP2011/080531 filed Dec. 29, 2011, claiming priority based on Japanese Patent Application No. 2011-014598filed Jan. 26, 2011, the contents of all of which are incorporated herein by reference in their entirety.
TECHNICAL FIELD
The present invention relates to a gripping device, a transfer device with the gripping device and a method for controlling a gripping device.
BACKGROUND ART
Conventionally, if a gripping device for gripping works is used to grip various works having different shape from each other, contact sections of the gripping device which directly contact the works should be changed corresponding to the shape of the work to be gripped. Thus, it is desired that the gripping device is capable of flexibly dealing with various works having different shapes from each other.
For example, JP 2008-528408 A or JP H09-123082 A discloses such gripping device that can grip various works having different shapes from each other.
The gripping device of JP 2008-528408 A or JP H09-123082 A is provided with contact sections including flexible bags containing a large number of particulate substances. The vacuum pump or the like is used to evacuate the inside of the bags or to release the vacuum, whereby the shape of the contact sections can be changed corresponding to the work shape.
The gripping operation of the gripping device makes the contact sections contact the work in order to change the shapes of the contact sections along the shape of the work, after that the flexible bags are vacuumed. Thereby, a lot of particulate substance is anchored with each other, and the shapes of the contact sections are maintained corresponding to that of the work. Releasing the vacuum of the flexible bags, the shapes of the contact sections are returned to the soft state.
CITATION LIST
Patent Literature
PTL 1: JP 2008-528408 A
PTL 2: JP H09-123082 A
SUMMARY OF INVENTION
Technical Problem
In the conventional gripping device, if the contact sections repeatedly grip the work at one contact point, the bags filled with the particulate substances suffer from the damage at the particular point, so that that point is likely to break. As the result of that, the conventional gripping device may have a short lifetime.
The objective of the present invention is to provide a technique of gripping various works having different shapes from each other and providing longer operating life than the conventional technique.
Technical Solutions
The first embodiment according to the invention relates to a gripping device for gripping a work which includes: a gripping unit for gripping the work; a controller for controlling the gripping operation of the gripping unit; and multiple contact sections attached to the gripping unit at contact points with the work, each of the contact sections being deformable following the outer shape of the work and being able to maintain the deformed shape. The gripping operation of the gripping unit makes the contact sections pressed to the work and deformed along the outer shape of the work, and the gripping unit grips the work where the deformed shape of the contact section is maintained. The controller changes the contact points of the contact sections with the work after gripping at predetermined times.
In a preferable embodiment of the invention, the controller shifts the contact points of the contact sections in a plane perpendicular to a gripping direction of the gripping unit.
The contact section preferably includes a bag in which a group of particulate substances are filled.
Furthermore, the shape of the contact section is maintained by evacuating the inside of the bag and increasing a volume ratio of the particulate substances relative to the internal volume of the bag so as to anchor the particulate substances with each other.
The second embodiment according to the invention relates to a transfer device, which is provided with the gripping device of the first embodiment. The transfer device is used for transferring the work upon gripping the work with the gripping device, and the transfer device comprises a robot arm adjusting the relative position between the gripping device and the work, the action of the robot arm being controlled by the controller.
The third embodiment according to the invention relates to a method for controlling a gripping device. The gripping device includes: a gripping unit for gripping the work; and multiple contact sections attached to the gripping unit at contact points with the work, each of the contact sections being deformable following the outer shape of the work and being able to maintain the deformed shape, wherein the gripping operation of the gripping unit makes the contact sections pressed to the work and deformed along the outer shape of the work, and the gripping unit grips the work where the deformed shape of the contact section is maintained. The controlling method includes changing the contact points of the contact sections with the work after gripping at predetermined times.
In the advantageous embodiment, the contact points of the contact sections are shifted in a plane perpendicular to a gripping direction of the gripping unit.
Advantageous Effects Of Invention
The embodiment according to the present invention provides the technique of gripping various works having different shapes from each other and providing longer operating life than the conventional technique.
Furthermore, without changing the structure of the conventional gripping device, the contact sections can prevent the local damage due to wear or tear.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 depicts a transfer device, ( a ) shows a block diagram and ( b ) shows a front view (X-Z plane).
FIG. 2 depicts a gripping device, ( a ) is a front view (X-Z plane), ( b ) shows A-A section view, and ( c ) shows B-B section view.
FIG. 3 illustrates a gripping operation of the gripping device, ( a ) is a front view (X-Z plane) and ( b ) shows a top view (X-Y plane).
FIG. 4 is a flow sheet of controlling the gripping device.
FIG. 5 is a perspective view showing a changing of the contact point of the gripping device.
DESCRIPTION OF EMBODIMENTS
Referring to FIGS. 1 to 3 , the structure of a transfer device 15 with a gripping device 1 is described.
Notice that in this embodiment, the XYZ coordinates as shown in FIGS. 1 and 2 are defined in the griping device.
As shown in FIG. 1 , the transfer device 15 is used for transferring a work 50 , including the gripping device 1 and a robot arm 16 . The transferring device 15 holds the work 50 by the gripping device 1 and transfers the work 50 from the initial place to the desired place.
As shown in FIG. 1 , the gripping device 1 includes a gripping unit 2 , a controller 7 and vacuum equipment 8 . The gripping device 1 is disposed at the hand 16 a of the robot arm 16 .
The gripping unit 2 directly grips the work 50 , and includes an actuating unit 3 , multiple claws 4 and 5 , multiple contact sections 6 .
As depicted in FIG. 2 , the actuating unit 3 has two sliders 3 a and 3 b . The actuating unit 3 telescopically moves the sliders 3 a and 3 b separately in the X direction. The actuating unit 3 may be an electric actuator with reciprocating equipment having a ball screw, a nut and a motor.
The actuating unit 3 is electrically connected to the controller 7 , which controls the movements of the sliders 3 a and 3 b of the actuating unit 3 .
The pair of the claws 4 and 5 is configured to clamp the work. The claws 4 and 5 clamp and hold the work 50 located therebetween.
The structure of the claws 4 and 5 can be changed in accordance with a shape or size of the work, or with stroke amounts of the sliders 3 a and 3 b.
As depicted in FIG. 2 , the first claw 4 has a support 4 a fixed to the slider 3 a and two clamp portions 4 b supported by the support 4 a . The clamp portions 4 b are arranged apart from each other by the predetermined distance.
The second claw 5 has a support 5 a fixed to the slider 3 b and a clamp portion 5 b supported by the support 5 a.
The controller 7 actuates the sliders 3 a and 3 b , whereby the clamp portions 4 b , 5 b move telescopically in the X-direction. In such manner, the claws 4 and 5 move in the X-direction, and the clamping portions 4 b and 5 b hold the work 50 at three points from the lateral direction (X-direction).
The contact sections 6 of the gripping device 1 directly contact the work 50 . Each contact section can provide a flexible structure and a solid structure, and can change the structure from the flexible structure to the solid structure (hardening) or from the solid structure to the flexible structure (softening). In the initial state of the gripping device 1 , the contact sections 6 are in the flexible state (softened).
As illustrated in FIG. 2 , the contact section 6 includes an elastic bag 6 a , and a group of particulate substances 6 b filled in the bag 6 a.
The contact sections 6 are attached to the clamping portions 4 b , 5 b of the claws 4 , 5 to face each other.
As depicted in FIG. 1( a ), each of the contact sections 6 is connected to the vacuum equipment 8 . The vacuum equipment 8 is configured to soften or harden the contact sections 6 , and includes a vacuum pump 8 a , a vacuum pipe 8 b and an electric valve 8 c . The bag 6 a of the contact section 6 is communicated to the vacuum pipe 8 b.
In the embodiment, the vacuum equipment 8 includes the vacuum pump 8 a , but the other evacuating means such as an ejector may be employable.
Furthermore, the gripping device can employ various structures for softening and hardening the contact sections, i.e., means for softening and hardening the contact section is not limited to the vacuum equipment.
For instance, the vacuum pump 8 a can be substituted for a check valve connected to the vacuum pipe 8 b to evacuate air from the bag 6 a . In such structure, the gripping operation leads the evacuation of air from the bag 6 a , thereby hardening the contact section 6 .
Evacuating the inside of the bag 6 a by means of the vacuum pump 8 a , the particulate substances 6 b filled in the bag 6 a are anchored with each other and the contact section 6 is hardened, whereby the shape of the contact section is solidly maintained.
In the softened state as shown in FIG. 3 (( a ) and ( b )), the contact sections 6 can be entered into the uneven surface including holes and projections existing on the surface of the work 50 by the clamping force acted by the clamp portions 4 and 5 . The shapes of the contact sections 6 are deformed following the outer surface of the work 50 .
After the contact sections 6 change their shapes corresponding to the outside of the work, the vacuum equipment 8 works, thereby hardening the contact sections 6 while the shapes are maintained. Thus, the solid contact sections 6 are formed in the shape corresponding to the outer shape of the work.
In this embodiment, the contact sections 6 are hardened by evacuating the inside of the bags 6 a , but the gripping device according to the invention may employ various structures. For example, the particulate substances are substituted for magnetic powder, and the magnetic force due to the magnetic powder hardens the contact sections.
As depicted in FIG. 3 , in the gripping unit 2 , the clamping portion 5 b is located at the center of the clamping portions 4 b in the Y direction. Thus, three contact sections 6 disposed on the clamping portions 4 b , 5 b steadily grip the work 50 . Such simple structure brings stable gripping, which can bear the swinging of the work 50 .
In the embodiment, the gripping unit 2 has three-point support structure, but the work 50 may be held by means of other structure, such as two-point mounting with wide clamping portions or four-point support.
As depicted in FIG. 1 , upon the transferring operation using the transfer device 15 , the work 50 is positioned by positioning pins 16 b and located at the predetermined position of a mounting place 16 c.
The controller 7 is electrically connected to the robot arm 16 in which information regarding the position or angle of the hand 16 a of the robot arm 16 is transmitted to the controller 7 as a feedback.
Referring to FIGS. 1 and 3 , the controlling structure for the gripping device 1 and robot arm 16 , during gripping the work 50 with the gripping device 1 , is described below.
Controlling the robot arm 16 , the position and angle of the hand 16 a are adjusted such that the gripping unit 2 is located in the predetermined place being suitable to hold the work 50 . In other words, the robot arm 16 adjusts the relative position between the gripping device 1 and the work 50 . In the embodiment, the position of the gripping unit 2 is set such that the contact sections 6 face the predetermined points of the work 50 .
Thereafter, the controller 7 receives the signal from the robot arm 16 that the gripping unit 2 is located in the suitable position to hold the work 50 .
After that, the controller 7 adjusts the strokes of the sliders 3 a , 3 b such that the distance between the claws 4 and 5 is smaller than the width of the work 50 . The pair of the claws 4 , 5 clamps the work 50 at the predetermined clamping pressure.
At that time, the contact sections 6 are pressed toward the work 50 and therefore deformed in accordance with the outer configuration of the work 50 .
Clamping the work 50 with the predetermined pressure by the claws 4 and 5 , the controller 7 transmits the signal to the vacuum pump 8 a in order to evacuate the inside of the bag 6 a of the contact sections 6 . Thus, the group of the particulate substances 6 b of the contact sections 6 is hardened in the shape corresponding to the outer shape of the work 50 .
The contact sections 6 are hardened being sunk into the predetermined points of the work 50 , so that the gripping unit 2 can hold the various works 50 each of which has different shape from each other without changing the gripping unit.
In the embodiment, the controller 7 adjusts the strokes of the sliders 3 a , 3 b so as to deform the contact sections 6 in response to the outer surface of the work 50 , namely the contact sections 6 are controlled by their positions. However, the gripping structure is not limited to the embodiment. For example, detecting the servo electric current or torque amount while moving the sliders 3 a and 3 b , the stable gripping is determined by sensing that the torque mount becomes the predetermined value, i.e., the sliders 3 a and 3 b may be controlled by the torque amount thereof. Additionally, the gripping device may have both controlling structures based on the position control and torque control in order to deform the contact sections according to the work shape.
Hereinafter, referring to FIGS. 4 and 5 , the method of controlling the gripping device 1 is described.
The gripping device 1 includes contact sections 6 capable of being hardened with shapes in accordance with the outer shape of the work 50 . Therefore, the gripping device can keep gripping even if the contact sections 6 do not contact the same points of the work 50 .
The gripping device 1 utilizes the features and grips the work 50 positively changing the contact points of the contact sections 6 with the work 50 . The controller 7 memorizes the following program to change the gripping position.
As shown in FIG. 4 , at the start of gripping operation by the gripping device 1 , the controller 7 sets the initial position ((X, Y, Z) coordinate of the gripping unit 2 ) of the gripping device 1 where the work 50 is suitably gripped (STEP- 1 ).
The controller 7 subsequently sets the initial number ([a]=0) of the transfer count [a] of the transfer device 15 (STEP- 2 ). The controller also sets the initial number ([b]=0) of the gripping count [b] with the gripping device 1 (STEP- 3 ).
Based on the control signal from the controller 7 , the robot arm 16 moves the gripping unit 2 such that each of the contact sections 6 faces the corresponding gripping points of the work 50 (STEP- 4 ).
Based on the control signal from the controller 7 , the actuating unit 3 is actuated so that the gripping unit 2 grips the work 50 (STEP- 5 ).
The controller 7 adds “1” to the gripping count [b], thereby counting the number of the work 50 which is gripped through the contact sections 6 installed in the gripping unit 2 (STEP- 6 ).
The controller 7 transmits the control signal to the robot arm 16 to transfer the work 50 to the predetermined place (STEP- 7 ).
Here, the controller 7 adds “1” to the transfer count [a], thereby counting the number of the work 50 which is transferred by the gripping device 1 (STEP- 8 ).
In the embodiment, the purpose of counting the transfer count [a] is to prevent the damage of the contact sections 6 while operating the manufacturing line, thereby preventing the unexpected stop of the line. The contact section 6 (or the bag 6 a ) has a certain lifetime based on the transfer count [a], and counting the number [a] allows the contact section 6 to be systematically changed before the contact section 6 has the damage. In an alternative method of setting the lifetime of the contact section 6 , detecting the vacuum degree of the bag 6 a after the evacuation, the contact section 6 will be replaced if the vacuum degree is lower than the predetermined value.
The controller 7 determines the lifetime on the basis of the transfer count [a] (STEP- 9 ).
If the transfer count [a] is less than a set value, the transferring operation is continued and followed by next STEP- 10 .
On the other hand, if the transfer count [a] is not less than the set value, the transferring operation is stopped.
In the embodiment, the control algorithm in the controlling process for the gripping device 1 includes the determining process based on the transfer count [a], however, the control algorithm may not include such determining process.
If the transfer count [a] is less than the set value, the controller 7 subsequently determines the lifetime based on the gripping count [b] (STEP- 10 ).
If the gripping count [b] is less than a set value, the former gripping points are maintained, and go back to the STEP- 4 .
If the gripping count [b] is not less than the set value, the controller 7 changes the gripping points (STEP- 11 ), and go back to the STEP- 3 .
In the embodiment, the STEP- 11 for changing the gripping points is performed by changing the positioning ((Y, Z) coordinate) of the gripping unit 2 by means of the robot arm 16 based on the control signal from the controller 7 . For instance, the positioning of the gripping unit 2 is shifted by 10 [mm] or more in the Y-direction (lateral direction) and Z-direction (vertical direction). Thus, the contact points of the contact sections 6 with respect to the work 50 change due to the gripping count, or change after gripping at predetermined number of times.
The changing amount or direction of the gripping points may be selected within the range capable of stably gripping the work 50 with the gripping unit 2 .
For example, once (every time) the gripping device 1 grips the work 50 , the gripping points may be changed, or after gripping three times, the gripping points may be changed. The frequency for change can be chosen in accordance with the operation condition of the gripping device 1 .
As a result, the contact sections 6 can be prevented from damages such as wear and tear in the particular point, thereby providing long lifetime of the contact sections 6 .
In the gripping device 1 , the contact points of the contact sections 6 with respect to the work 50 shift in the plane (Y-Z plane) perpendicular to the gripping direction (X-direction).
Therefore, without changing the conventional structure, the contact sections 6 can be easily prevented from local damages such as the wear or tear. Accordingly, the lifetime of the contact sections 6 can be improved.
In the embodiment, the robot arm 16 moves the gripping unit 2 , thereby adjusting the position of the gripping points. However, the gripping device is not limited to the structure, but may employ the structure wherein the contact sections are capable of moving relative to claws and the gripping points of the contact sections change by predetermined intervals.
Moreover, changing the arrangement of the gripping unit 2 , the gripping points for the work 50 are shifted, and the contact positions of the contact sections 6 are changed. However, the arrangement of the claws 4 and 5 may be changed for shifting the contact points of the contact sections 6 without modification of the structure of the gripping unit 2 .
In the STEP- 11 for changing the gripping points, the controller 7 preferably changes the displacement of the sliders 3 a and 3 b in the X-direction (stroke amount) in response to the shift of the gripping unit 2 in the Y-direction and Z-direction.
Thus, the contact sections 6 can be deformed along the outer shape of the work 50 , thereby securing the gripping force of the gripping unit 2 .
Industrial Applicability
The present invention can be applicable to a gripping device for gripping various works with various shapes.
Description of Numerals
1 : gripping device, 2 : gripping unit, 3 : actuating unit, 4 : claw, 5 : claw, 6 : contact section, 7 : controller, 15 : transfer device, 16 : robot arm, 50 : work | A gripping device comprises: a gripping unit for gripping a work; a controller for controlling the gripping operation of the gripping unit; and contact sections attached to the gripping unit contacting the work, the contact sections being adapted to deform following the shape of the work, and to maintain the deformation. The gripping operation of the gripping unit presses the contact sections against the work to cause the contact sections to follow the outside of the work, and grips the work with the shape of the contact sections maintained. After predetermined number of times of gripping operation, the controller changes the positions of the contact points of the contact sections with the work when the work is gripped. As a result, different works having different shapes can be stably gripped and the lifetime of the contact sections can be extended to be longer than that of conventional products. The change, by the controller, in the positions of the points on the work with which the contact sections are in contact when the work is gripped is performed by shifting the contact sections in a plane vertical to the gripping direction. | 8 |
FIELD OF THE INVENTION
The present invention relates to a method for designing of an elliptical structure, and the same.
BACKGROUND
Conventional building structures are typically square, rectangular, and circular in horizontal section, and although some of them use walls having a variety of curves as outer walls and the like, structures which horizontal section is elliptical are not often encountered. If structures which outer walls partly adopts an elliptic curve can be encountered, those which are entirely elliptical in horizontal section, in other words, which entire perimeter forms an elliptical cylinder are rarely encountered. However, structures which horizontal section is elliptical are extremely graceful in shape, and have a high strength, therefore, as future building structures providing a novel feeling and a beautiful appearance, they can be greatly expected to be popularized.
Then, the present invention provides efficient and economic means for serving the design, drawing, land survey, manufacture, and construction in building an elliptical structure.
The elliptic curve is a quadratic curve which is characterized in that the sum of the distances from a particular point thereon to the two focuses of ellipse is constant. For drawing an elliptic curve, two coordinate points which are to be on the elliptic curve may be connected to each other with a single straight line as a convenient method, or with a polygonal line approximate to the elliptic curve as a more precise method. However, for connecting two coordinate points to each other with a polygonal line, the distance between the two coordinate points must be finely divided, and minute polygonal line components must be drawn, being connected to one another. Therefore, to connect two coordinate points by means of such a polygonal line to provide an approximate elliptic curve, complex computations and operations are required. Thus, using such an approximate elliptic curve which is thus obtained means that it requires intricate calculations and drawings in designing an elliptical structure, and that it is not efficient, economical, and feasible in land surveying on the building site for the elliptical structure, and fabricating member materials for the structure.
SUMMARY OF THE INVENTION
The present invention eliminates these problems by connecting circular segments to provide an approximate elliptic curve. The locus of a circle is determined depending upon the center and the radius, and thus a circular segment can be easily drawn. Therefore, connecting circular segments to generate an approximate elliptic curve makes the design and drawing of elliptical structures substantially more efficient and provides feasible means for constructing elliptical structures.
The first purpose of the present invention is to provide an approximate elliptic curve for an elliptical structure by connecting circular segments.
The second purpose of the present invention is to provide a method for designing an elliptical structure efficiently, economically, and practically by connecting circular segments to generate an approximate elliptic curve.
The third purpose of the present invention is to provide an elliptical structure which can be efficiently, economically and practically designed by connecting circular segments to generate an approximate elliptic curve.
These purposes can be achieved by the present invention, which embodiments will be described here with reference to the accompanying drawings. It is needless to say that any possible modifications and variations of the present invention can be covered by the claims which are later given.
As shown in the accompanying drawings which are described later, the present invention provides the following items [1], [2], and [3]:
[1] A method for designing an elliptical structure (A) which is symmetrical about the major axis (M) and the minor axis (N) thereof, and has an outline (B 1 ) of an approximate elliptic curve, comprising the steps of:
a) establishing a first fixed point (C 1 ) outside the elliptical structure (A); from the first fixed point (C 1 ), drawing a straight line segment (L 0 ) to the farthest end point of the minor axis (N) through the intersecting point (o) of the major axis (M) and the minor axis (N); and drawing a first circular segment (d 1 ) from said farthest end point (P 0 ) of the minor axis (N) with the use of the first fixed point (C 1 ) as the center and the first straight line segment (L 1 ) having the same length as that of said straight line segment (L 0 ) as the radius, through an arbitrary angle a α 1 set at said first fixed point (C 1 );
b) establishing a second fixed point (C 2 ) on said first straight line segment (L 1 ); and drawing a second circular segment (d 2 ) following said first circular segment (d 1 ) with the use of the second fixed point (C 2 ) as the center and the second straight line segment (L 2 ) as the radius, through an arbitrary angle a α 2 set at said second fixed point (C 2 );
c) establishing a third fixed point (C 3 ) on said second straight line segment (L 2 ); and drawing a third circular segment (d 3 ) following said second circular segment (d 2 ) with the use of the third fixed point (C 3 ) as the center and the third straight line segment (L 3 ) as the radius, through an arbitrary angle α 3 set at said third fixed point (C 3 );
d) repeating this step as required;
e) finally drawing an nth circular segment (d n ) following (n−1)th circular segment (d n−1 ) and ranging from the finish end (P n−1 ) of the (n−1)th circular segment (d n−1 ) to the major axis (M) with the use of the intersecting point (C n ) of (n−1)th straight line segment (L n−1 ) and the major axis (M) as the center, and a part of the (n−1)th straight line segment (L n−1 ) as the radius; and
f) using these steps to draw a part of the outline (B 1 ) in each of the other quadrants for drawing the entire outline (B 1 ).
[2] A method for designing an elliptical structure (A) which is symmetrical about the major axis (M) and the minor axis (N) thereof, and has an outline (B 2 ) of an approximate elliptic curve, comprising the steps of:
a) establishing a first fixed point (C,) outside the elliptical structure (A); from the first fixed point (C 1 ), drawing a straight line segment (L 0 ) to the farthest end point (P 0 ) of the minor axis (N) through the intersecting point (o) of the major axis (M) and the minor axis (N); and drawing a first circular segment (d 10 ) from said farthest end point (P 0 ) of the minor axis (N) with the use of the first fixed point (C 1 ) as the center and a first straight line segment (L 10 ) having the same length as the straight line segment (L 0 ) as the radius, through an arbitrary angle α 1 set at said first fixed point (C 1 );
b) establishing a second fixed point (C 20 ) on said first straight line segment (L 10 ); and drawing a second circular segment (d 20 ) following said first circular segment (d 10 ) with the use of the second fixed point (C 20 ) as the center and the second straight line segment (L 20 ) as the radius, through an arbitrary angle α 2 set at said second fixed point (C 20 );
c) finally drawing a third circular segment (d 30 ) following the second circular segment (d 20 ) and ranging from the finish end (P 20 ) of the second circular segment (d 20 ) to the major axis (M) with the use of the intersecting point (C 30 ) of the second straight line segment (L 20 ) and the major axis (M) as the center, and a part of the second straight line segment (L 20 ) as the radius; and
d) using these steps to draw a part of the outline (B 2 ) in each of the other quadrants for drawing the entire outline (B 2 ).
[3] An elliptical structure (A) which has an outline (B 1 ), (B 2 ) of an approximate elliptic curve, being constructed using building materials designed by the method as mentioned in either of the item [1] and item [2].
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a bird's eye view of an elliptical structure (A) to be built on the present invention;
FIG. 2 is an example of elliptic curve drawn for the elliptical structure as shown in FIG. 1 ;
FIG. 3 shows an embodiment of the method for designing an elliptical structure according to the present invention; and
FIG. 4 shows another embodiment of the method for designing an elliptical structure according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a bird's eye view of an elliptical structure (A) to be built on the present invention. FIG. 2 is an example of elliptic curve drawn for the elliptical structure (A) as shown in FIG. 1 , which outline or perimeter basically forms an ellipse, the elliptic curve being provided as a result of mathematical computation made by manual operation or by using such means as a computer. The elliptic curve has a major axis (M) and a minor axis (N) on the coordinate axes x and y (providing center lines), respectively, a partial outline (b 1 ), (b 2 ), (b 3 ), and (b 4 ) in the first quadrant (I), the second quadrant (II), the third quadrant (III), and the fourth quadrant (IV), respectively, being connected to one another to provide a complete outline (B) which forms an ellipse, and the elliptic curve is symmetrical about the major axis (M) and also about the minor axis (N).
Thus, with the present invention, the elliptic curve for the elliptical structure (A) is provided by connecting circular segments to one another.
Specifically, as shown in FIG. 3 , an outline (B 1 ) approximating said outline (B) is created by connecting circular segments to one another. In other words, the major axis (M) and the minor axis (N) for the outline (B 1 ), i.e., the coordinate axes x and y are established, and a first fixed point (C 1 ) is established on the coordinate axis y. By drawing a straight line segment (L 0 ), which has a length equal to half the length of the previously established minor axis (N) plus the length from the first fixed point (C 1 ) to the major axis (M), i.e., the origin (o), which is the intersecting point of the major axis (M) and the minor axis (N), a point (P 0 ) which must exist on the outline (B 1 ) is determined. An angle α 1 is set at said first fixed point (C 1 ), and a first circular segment (d 1 ) is drawn from the point (P 0 ) to a point (P 1 ) with the first fixed point (C 1 ) being used as the center, and a first straight line segment (L 1 ), which length is set at the same as the length of the straight line segment (L 0 ), being used as the radius. In this context, the point (P 1 ) provides a point where a first tangent line segment (k 1 ) at the end of the first circular segment (d 1 ) forms a right angle with the first straight line segment (L 1 ), in other words, an angle γ 1 at the point (P 1 ) is 90 deg. The first circular segment (d 1 ) drawn provides the partial outline (b 1 ) as mentioned above.
Next, a point distant from the first fixed point (C 1 ) by an arbitrary length l 1 . is established as a second fixed point (C 2 ) on the first straight line segment (L 3 ); an angle of α 2 is set to draw a second straight line segment (L 2 ) to a point (P 2 ); and with the second fixed point (C 2 ) being used as the center, and the second straight line segment (L 2 ) being used as the radius, a second circular segment (d 2 ), which follows the first circular segment (d 1 ), is drawn to the point (P 2 ). The beginning of the second circular segment (d 2 ) provides a point where a second tangent line segment (k′ 1 ) at the start end of the second circular segment (d 2 ) forms a right angle with the first straight line segment (L 1 ), in other words, an angle γ′ 1 at the point (P 1 ) is 90 deg. Thus, the angle γ 1 plus the angle γ′ 1 is equal to 180 deg, and at the point (P 1 ), the first tangent line segment (k 1 ) for the first circular segment (d 1 ) and the second tangent line segment (k′ 1 ) at the start end of the second circular segment (d 2 ) form a straight line segment, thereby the first circular segment (d 1 ) drawn previously and the second circular segment (d 2 ) drawn subsequently are smoothly and curvedly connected to each other with no offset being produced.
Next, a point distant from the second fixed point (C 2 ) by an arbitrary length l 2 is established as a third fixed point (C 3 ) on the second straight line segment (L 2 ); an angle of α 3 is set to draw a third straight line segment (L 3 ) to a point (P 3 ); and with the third fixed point (C 3 ) being used as the center, and the third straight line segment (L 3 ) being used as the radius, a third circular segment (d 3 ), which follows the second circular segment (d 2 ), is drawn to the point (P 3 ). The beginning of the third circular segment (d 3 ) provides a point where a third tangent line segment (k 2 ) at the finish end of the second circular segment (d 2 ) and a fourth tangent line segment (k′ 2 ) at the start end of the third circular segment (d 3 ) form a right angle with the second straight line segment (L 2 ), respectively, in other words, an angle γ 2 , γ′ 2 at the point (P 2 ) is 90 deg. Thus, the angle γ 2 plus the angle γ′ 2 is equal to 180 deg, and at the point (P 2 ), the third tangent line segment (k 2 ) for the second circular segment (d 2 ) and the fourth tangent line segment (k′ 2 ) for the third circular segment (d 3 ) form a straight line segment, thereby the second circular segment (d 2 ) drawn previously and the third circular segment (d 3 ) drawn subsequently are smoothly and curvedly connected to each other with no offset being produced.
Next, a point distant from the third fixed point (C 3 ) by an arbitrary length l 3 is established as a fourth fixed point (C 4 ) on the third straight line segment (L 3 ); an angle of α 4 is set to draw a fourth straight line segment (L 4 ) to a point (P 4 ); a point where the major axis (M) intersects with the fourth straight line segment (L 4 ) is established as a fifth fixed point (C 5 ), which is the final fixed point; and a fifth circular segment (d 5 ), which follows the fourth circular segment (d 4 ), is drawn to the major axis (M) to provide a point (P 5 ). By this, one end of the major axis (M) is actually established. The angle which the third straight line segment (L 3 ) forms with tangent line segments at the point (P 3 ) and that which the fourth straight line segment (L 4 ) forms with tangent line segments at the point (P 4 ) are 180 deg (as a result of 90 deg plus 90 deg), respectively, as is the case at the point (P 2 ). In this way, a partial outline (b 1 ) is sequentially formed in the first quadrant (I) for the outline (B 1 ).
If the values of angles α 1 , α 2 , α 3 , and α 4 , and the values of lengths l 1 l 2 , and l 3 are given, the values of lengths l 4 and l 5 can be determined by calculation (as later described). Then, as can be easily conjectured from FIG. 4 (although this figure illustrates another embodiment of the present invention), the same technique is used to draw a partial outline (b 2 ) at left of the first fixed point (C 1 ) in the second quadrant (II) for the outline (B 1 ), and for the third quadrant (III) and the fourth quadrant (IV), a fixed point (C′ 1 ) is established at the point symmetrical to the first fixed point (C 1 ), and by the same technique, partial outlines (b 3 ) and (b 4 ) are drawn. Now, said entire outline (B 1 ) has been formed by these partial outlines (b 1 ), (b 2 ), (b 3 ) and (b 4 ). By increasing the number of angles α, as α 1 , α 2 , α 3 , α 4 , and α 5 , . . . , and the number of straight line segments L, as L 1 , L 2 , L 3 , and L 4 , . . . , the deviation of the components of the outline (B 1 ) from the corresponding components of the real elliptic curve can be decreased, in other words, the precision of the outline (B 1 ) created can be enhanced.
In FIG. 3 , the length of the straight line segment (L 0 ) is equal to the distance between the first fixed point (C 1 ) and the point (P 0 ); the length of the first straight line segment (L 1 ) is equal to the distance between the first fixed point (C 1 ) and the point (P 1 ); the length of the second straight line segment (L 2 ) is equal to the distance between the second fixed point (C 2 ) and the point (P 2 ); the length of the fourth straight line segment (L 4 ) is equal to the distance between the fourth fixed point (C 4 ) and the point (P 4 ); (although it is not indicated in the figure), the length of the nth straight line segment (L n ) is equal to the distance between the nth fixed point (C n ) and the point (P n ); and the intersecting point of the major axis (M) and the (n−1)th straight line segment (L n−1 ) provide the nth fixed point (C n ), which is the final fixed point.
Further, in FIG. 3 , the length l 1 is equal to the distance between the first fixed point (C 1 ) and the second fixed point (C 2 ); the length l 2 is equal to the distance between the second fixed point (C 2 ) and the third fixed point (C 3 ); the length l 3 is equal to the distance between the third fixed point (C 3 ) and the fourth fixed point (C 4 ); the length l 4 is equal to the distance between the fourth fixed point (C 4 ) and the fifth fixed point (C 5 ); and here the distance between the fifth fixed point (C 5 ) and the point (P 4 ) is equal to the distance between the fifth fixed point (C 5 ) and the point (P 5 ), therefore, the length of the fifth straight line segment (L 5 ) is equal to the length l 5 . Here, the length of the fifth straight line segment (L 5 ) is equal to the distance between the fifth fixed point (C 5 ) and the point (P 5 ), which is equal to the length of the fourth straight line segment (L 4 ) minus the length l 4 . The fifth fixed point (C 5 ) is said final fixed point, which provides the intersecting point of the fourth straight line segment (L 4 ) drawn from the fourth fixed point (C 4 ) and the major axis (M). By drawing a fifth circular segment (d 5 ), which follows the fourth circular segment (d 4 ), from the point (P 4 ) to the major axis (M), with the fifth fixed point (C 5 ) being used as the center, said point (P 5 ) is provided. Thereby, as stated above, the partial outline (b 1 ) is completed in the first quadrant. Here, if a straight line segment (s) which is parallel to the y axis is drawn from the fourth fixed point (C 4 ) toward the x axis, the angle θ formed between the straight line segment (s) and the fourth straight line segment (L 4 ) is equal to the sum of the angles α 1 , α 2 , α 3 , and α 4 .
Hereinbelow, it will be described that, by arbitrarily determining the distance between the first fixed point (C 1 ) and the point (P 0 ), the distance between the first fixed point (C 1 ) and the origin (o), half the length of the minor axis (N), i.e., [N/2], the lengths l 1 , l 2 , and l 3 , the angles α 1 , α 2 , α 3 , and α 4 , the lengths l 4 and l 5 can be determined. In FIG. 3 , it is assumed that the intersecting point of a straight line drawn from the second fixed point (C 2 ) in parallel with the x axis and intersecting with the y axis is E 1 , the distance between the first fixed point (C 1 ) and E 1 is l′ 1 ; the intersecting point of a straight line drawn from the third fixed point (C 3 ) in parallel with the x axis and intersecting with the y axis is E 2 , the distance between E 1 and E 2 is l′ 2 ; and the intersecting point of a straight line drawn from the fourth fixed point (C 4 ) in parallel with the x axis and intersecting with the y axis is E 3 , the distance between E 2 and E 3 is l′ 3 . Then, l′ 2 is equal to the distance between E 1 and E 2 ; l′ 3 is equal to the distance between E 2 and E 3 ; and l′ 4 is equal to the distance between E 3 and the origin (o). Here is a description using mathematical expressions.
cos
α
1
=
l
1
′
l
1
l
1
=
l
1
′
cos
α
1
l
1
′
=
l
1
cos
α
1
(
1
)
l
2
=
l
2
′
cos
(
α
1
+
α
2
)
l
2
′
=
l
2
cos
(
α
1
+
α
2
)
(
2
)
l
3
=
l
3
′
cos
(
α
1
+
α
2
+
α
3
)
l
3
′
=
l
3
cos
(
α
1
+
α
2
+
α
3
)
(
3
)
If C 1,0 denotes the distance between C 1 and o, and P 0 , C 1 the distance between P 0 and C 1 ,
C 1,0 =P 0 , C 1 −N/ 2
is a known number, and l′ 1 , l′ 2 , and l′ 3 can be calculated from the above equations (1), (2), and (3), thus, l′ 4 can be determined from the equation:
l′ 4 =C 1,0 −l′ 1 −l′ 2 −l′ 3
Then, by the equation:
cos θ = l 4 ′ l 4
the value of l 4 can be determined as follows:
l 4 = l 4 ′ cos θ
where θ is expressed by the following equation:
θ=α 1 +α 2 +α 3 +α 4
Then, the length of the fourth straight line segment (L 4 ) is equal to the length of the straight line segment (L 0 ) minus (l 1 +l 2 +l 3 ), and l 5 is equal to the length of L 4 minus l 4 , thus, the value of l 5 can be calculated.
The length of the nth straight line segment (L n ), where n≧2, is equal to the length of the (n−1)th straight line segment (L n−1 ) minus l n−1 , where l n−1 is expressed by the following equation:
l
n
-
1
=
l
n
-
1
′
cos
(
α
1
+
α
2
+
⋯
+
α
n
-
1
)
FIG. 4 shows another embodiment. In FIG. 4 , to create an outline (B 2 ) which approximate said outline (B), the major axis (M) and the minor axis (N) for the outline (B 2 ) of a building (A), i.e., the coordinate axes x and y are established; a first fixed point (C 1 ) is established on the coordinate axis y; by drawing a straight line segment (L 0 ), which has a length equal to half the length of the previously established minor axis (N) plus the length from the first fixed point (C 1 ) to the major axis (M), i.e., the origin (o), which is the intersecting point of the major axis (M) and the minor axis (N), a point (P 0 ) which must exist on the outline (B 2 ) is determined; an angle α 1 is set at said first fixed point (C 1 ); a first circular segment (d 10 ) is drawn from the point (P 0 ) to a point (P 10 ) with the first fixed point (C 1 ) being used as the center, and a first straight line segment (L 10 ), which length is set at the same as the length of the straight line segment (L 0 ), being used as the radius. The point (P 10 ) provides a point where an angle γ 1 at the point (P 10 ) is 90 deg, in other words, a first tangent line segment (k 10 ) at the end of the first circular segment (d 10 ) forms a right angle with the first straight line segment (L 10 ).
Next, a point distant from the first fixed point (C 1 ) by an arbitrary length l 10 is established as a second fixed point (C 20 ) on the first straight line segment (L 10 ); An angle of α 2 is set to draw a second straight line segment (L 20 ) to a point (P 20 ); and with the second fixed point (C 20 ) being used as the center, and the second straight line segment (L 20 ) being used as the radius, a second circular segment (d 20 ), which follows the first circular segment (d 10 ), is drawn to the point (P 20 ). The beginning of the second circular segment (d 20 ) provides a point where a second tangent line segment (k′ 10 ) at the start end of the second circular segment (d 20 ) forms a right angle with the first straight line segment (L 10 ), in other words, an angle γ′ 1 at the point (P 10 ) is 90 deg. Thus, the angle γ 1 plus the angle γ′ 1 is equal to 180 deg, and at the point (P 10 ), the first tangent line segment (k 10 ) for the first circular segment (d 10 ) and the second tangent line segment (k′ 10 ) at the start end of the second circular segment (d 20 ) form a straight line segment, thereby the first circular segment (d 10 ) drawn previously and the second circular segment (d 20 ) drawn subsequently are smoothly and curvedly connected to each other with no offset being produced.
Also at the point (P 20 ), the angle γ 2 plus the angle γ′ 2 is equal to 180 deg, and at the point (P 20 ), a third tangent line segment (k 20 ) for the second circular segment (d 20 ) and a fourth tangent line segment (k′ 20 ) at the start end of a third circular segment (d 30 ) (later described) form a straight line segment, thereby the second circular segment (d 20 ) drawn previously and the third circular segment (d 30 ) drawn subsequently are smoothly and curvedly connected to each other with no offset being produced.
In this case, the second circular segment (d 20 ) intersects with the major axis at an angle of α 3 , and the sum of the angles α 1 , α 2 , and α 3 is equal to 90°. By using this intersecting point as a third fixed point (C 30 ) (the final fixed point), the third circular segment (d 30 ), which follows the second circular segment (d 20 ), is drawn to the major axis (M). Thereby, one end of the major axis (M), i.e., a point (P 30 ), is determined. In this way, a partial outline (b 1 ) is sequentially formed in the first quadrant (I) for the outline (B 2 ).
In FIG. 4 , the length of the straight line segment (L 0 ) is equal to the distance between the first fixed point (C 1 ) and the point (P 0 ); the length of the first straight line segment (L 10 ) is equal to the distance between the first fixed point (C 1 ) and the point (P 10 ); and the length of the second straight line segment (L 20 ) is equal to the distance between the second fixed point (C 20 ) and the point (P 20 ). Therefore, if the values of angles α 1 and α 2 , and the value of length l 10 are given, the length of the second straight line segment (L 20 ) is determined, and the values of lengths l 20 and l 30 can be determined by calculation. In other words, if the third fixed point (C 30 ) is established, the length l 20 can be determined, and thus the length l 30 can be determined from the relationship: the length l 30 is equal to the length of the second straight line segment (L 20 ) subtracted by the length l 20 .
Thus, also in the present embodiment, the elliptic curve for an elliptical structure (A) can be formed by connecting circular segments to one another.
Then, as shown in FIG. 4 , the same technique is used to draw a partial outline (b 2 ) at left of the first fixed point (C 1 ) in the second quadrant (II) for the outline (B 2 ), and for the third quadrant (III) and the fourth quadrant (IV), a fixed point (C′ 1 ) is established at the point symmetrical to the first fixed point (C 1 ), and by the same technique, partial outlines (b 3 ) and (b 4 ) are drawn. Now, said entire outline (B 2 ) has been formed by these partial outlines (b 1 ), (b 2 ), (b 3 ) and (b 4 ).
Thus, with the present invention, the members based on the first circular segment (d 1 ) to the fifth circular segment (d 5 ), and the first circular segment (d 1 ) to the third circular segment (d 3 ) as shown in FIGS. 3 and 4 , respectively, are individually designed and manufactured to be connected to one another for creating building materials for all the four quadrants, which are then assembled to one another to provide a particular floor of the elliptical structure (A), and all the floors are jointed to one another to provide an entire elliptical structure (A).
The present invention can provide efficient and economic means for serving the design, drawing, land survey, manufacture, and construction in building an elliptical structure on a particular site. The present invention allows forming the outline of an elliptical structure by connecting circular segments while smoothly forming the joint of the respective circular segments, and makes it possible to perform the related computation by setting the radii of the respective circular segments and the required angles, thus permitting efficient construction of elliptical structures. Such elliptical structures are excellent in structural strength, durable, and helpful to prevent strong wind blowing along a street of highrise buildings. | A method for designing an elliptical structure with an outline of an approximate elliptic curve, which is generated by connecting circular segments to one another, and an elliptical structure created on said method. A first fixed point is established outside the elliptical structure; from the first fixed point, a straight line segment is drawn to the farthest end point of the minor axis through the origin; a first circular segment is drawn from said farthest end point of the minor axis with the use of the first fixed point as the center and the first straight line segment having the same length as that of said straight line segment as the radius, through an arbitrary angle set at said first fixed point; a second fixed point is established on said first straight line segment; a second circular segment following said first circular segment is drawn with the use of the second fixed point as the center and the second straight line segment as the radius, through an arbitrary angle set at said second fixed point; this step is repeated as required; an nth circular segment following (n−1)th circular segment and ranging from the finish end of the (n−1)th circular segment to the major axis is drawn with the use of the intersecting point of (n−1)th straight line segment and the major axis as the center, and a part of the (n−1)th straight line segment as the radius; and these steps are used to draw a part of the outline in each of the other quadrants for drawing the entire outline. | 4 |
REFERENCE TO EARLIER FILED APPLICATIONS
"This is a continuation of copending U.S. patent application(s) Ser. No. 07/556,111 filed on Jul. 20, 1990, now abandoned which is a continuation of U.S. patent application Ser. No. 06/916,402, entitled PENETRATION EXCHANGERS FOR TRANSDERMAL DELIVERY OF SYSTEMIC AGENTS, filed Oct. 7, 1986, now abandoned, which was a continuation-in-part of U.S. patent application Ser. No. 06/824,436, filed on Jan. 31, 1986, now abandoned.
BACKGROUND OF THE INVENTION
1) Field of the Invention
The invention generally relates to an improved method of drug delivery. More particularly, the invention relates to an improved membrane penetration enhancer for use in the transdermal delivery of systemically active drugs to humans and animals.
2) Background of the Prior Art
For some years, pharmaceutical researchers have sought an effective means of introducing drugs into the bloodstream by applying them to unbroken skin. Among other advantages, such administration can provide a comfortable, convenient, and safe way of giving many drugs now taken orally or infused into veins or injected intramuscularly.
Using skin as the portal for drug entry offers unique potential, because transdermal delivery permits close control over drug absorption. For example, it avoids factors that can cause unpredictable absorption from the gastrointestinal tract, including: changes in acidity, motility, and food content. It also avoids initial metabolism of the drug by the liver. Thus, controlled drug entry through skin can achieve a high degree of control over blood concentrations of drug.
Close control over drug concentrations in blood can translate readily into safer and more comfortable treatment. When a drug's adverse effects occur at higher concentrations than its beneficial ones, rate control can maintain the concentrations that evoke only--or principally--the drug's desired actions. This ability to lessen undesired drug actions can greatly reduce the toxicity hazards that now restrict or prevent the use of many valuable agents.
Transdermal delivery particularly benefits patients with chronic disease. Many such patients have difficulty following regimens requiring several doses daily of medications that repeatedly cause unpleasant symptoms. They find the same drugs much more acceptable when administered in transdermal systems that require application infrequently--in some cases, only once or twice weekly--and that reduce adverse effects.
Transdermal delivery is feasible for drugs effective in amounts that can pass through the skin area and that are substantially free of localized irritating or allergic effects. While these limitations may exclude some agents, many others remain eligible for transdermal delivery. Moreover, their numbers will expand as pharmaceutical agents of greater potency are developed. Particularly suitable for transdermal delivery are potent drugs with only a narrow spread between their toxic and safe blood concentrations, those having gastrointestinal absorption problems, or those requiring frequent dosing in oral or injectable form.
Transdermal therapy permits much wider use of natural substances such as hormones. Often the survival times of these substances in the body are so short that they would have to be taken many times daily in ordinary dosage forms. Continuous transdermal delivery provides a practical way of giving them, and one that can mimic the body's own patterns of secretion.
At present, controlled transdermal therapy appears feasible for many drugs used for a wide variety of ailments including, but not limited to, circulatory problems, hormone deficiency, respiratory ailments, and pain relief.
Percutaneous administration can have the advantage of permitting continuous administration of drug to the circulation over a prolonged period of time to obtain a uniform delivery rate and blood level of drug. Commencement and termination of drug therapy are initiated by the application and removal of the dosing devices from the skin. Uncertainties of administration through the gastrointestinal tract and the inconvenience of administration by injection are eliminated. Since a high concentration of drug never enters the body, problems of pulse entry are overcome and metabolic half-life is not a factor of controlling importance.
U.S. Pat. Nos. 3,989,815; 3,989,816; 3,991,203; 4,122,170; 4,316,893; 4,415,563; 4,423,040; 4,424,210; 4,444,762 and 4,755,535 generally describe a method for enhancing the topical (as contrasted to the systemic) administration of physiologically active agents by combining such an agent with an effective amount of a penetration enhancer and applying the combination topically to humans or animals, in the form of creams, lotions, gels, etc.
Penetration enhancers for enhancing systemic administration of therapeutic agents transdermally are cited in U.S. Pat. Nos. 4,405,616; 4,562,075; 4,031,894, 3,996,934; and 3,921,636.
SUMMARY OF THE INVENTION
It has been discovered that the penetration enhancers, previously disclosed in U.S. patent application Ser. No. 06/824,436 to enhance topical delivery of physiologically active agents, also enhance the transdermal delivery of systemically active agents through the skin or other body membranes of humans and animals directly in the bloodstream without localized irritating or allergic effects on the skin, i.e., the penetration enhancers are non-toxic.
The invention therefore provides a method for topically administering systemically active agents through the skin or mucosal membranes of humans and animals, utilizing a transdermal device or formulation, wherein the improvement in said method comprises topically administering with said systemic agent an effective amount of a non-toxic, effective, membrane penetration enhancer having the structural formula ##STR3## wherein X may represent sulfur or two hydrogen atoms; R' is H or a lower alkyl group having 1-4 carbon atoms; m is 2-6; n is 0-18 and R is --CH 3 , ##STR4## wherein R" is H or halogen. The topical administration of the non-toxic, effective membrane penetration enhancer may be simultaneous with, before, or after topical administration of the therapeutic agent.
The invention also provides an improved method for administering systemically active therapeutic agents topically through the skin of humans in a transdermal device or formulation to obtain therapeutic blood levels of the therapeutic agent, wherein the improvement in said method comprises the use of non-toxic, effective skin penetration enhancing amount of the above membrane penetration enhancer with said therapeutic agent.
Preferably R is --CH 3 and R' is H.
In a more preferred embodiment of the present invention R is --CH 3 , R' is H and m equals 4. Even more preferably n is 4-17, e.g., 11.
DETAILED DESCRIPTION OF THE INVENTION
The compounds useful as non-toxic, membrane penetration enhancers in the formulations or devices of the instant invention may be made as described in U.S. patent application Ser. No. 06/824,436, hereby incorporated by reference. Typical examples of compounds represented by the above structural formula include:
1-n-Dodecylazacycloheptane
1-n-Dodecylazacycloheptan-2-one
1-n-Dodecylazacycloheptan-2-thione
1-n-Butylazacyclohexan-2-thione
1-n-Butylazacyclopentan-2-thione
1-n-Octylazacyclopentan-2-thione
1-n-Butylazacycloheptan-2-thione
1-n-Octylazacycloheptan-2-thione
1,1'-Hexamethylenediazacyclopentan-2-thione
1-n-Dodecylazacyclohexan-2-thione
1-n-Decylazacycloheptane
1-n-Hexadecylazacycloheptane
1-n-Octadecylazacycloheptane
1-n-Undecylazacycloheptane
1-n-Tetradecylazacycloheptane
Typical systemically active agents which may be delivered transdermally are therapeutic agents which are sufficiently potent such that they can be delivered through the skin or other membrane to the bloodstream in sufficient quantities to produce the desired therapeutic effect. In general, this includes therapeutic agents in all of the major therapeutic areas including, but not limited to, anti-infectives, such as antibiotics and antiviral agents, analgesics and analgesic combinations, anorexics, anthelmintics, antiarthritics, antiasthma agents, anticonvulsants, antidepressants, antidiabetic agents, antidiarrheals, antihistamines, anti-inflammatory agents, antimigraine preparations, antimotion sickness, antinauseants, antineoplastics, antiparkinsonism drugs, antipruritics, antipsychotics, antipyretics, antispasmodics, including gastrointestinal and urinary; anticholinergics, sympathomimetics, xanthine derivatives, cardiovascular preparations including calcium channel blockers, beta-blockers, antiarrhythmics, antihypertensives, diuretics, vasodilators including general, coronary, peripheral and cerebral; central nervous system stimulants, cough and cold preparations, decongestants, diagnostics, hormones, hypnotics, immunosuppressives, muscle relaxants, parasympatholytics, psychostimulants, sedatives and tranquilizers.
Dosage forms for application to the skin or other membranes of humans and animals include creams, lotions, gels, ointments, suppositories, sprays, aerosols, buccal and sublingual tablets and any one of a variety of transdermal devices for use in the continuous administration of systemically active drugs by absorption through the skin, oral mucosa or other membranes, see for example, one or more of U.S. Pat. Nos. 3,598,122; 3,598,123; 3,731,683; 3,742,951; 3,814,097; 3,921,636; 3,972,995; 3,993,072; 3,993,073, 3,996,934; 4,031,894; 4,060,084; 4,069,307; 4,201,211; 4,230,105; 4,292,299 and 4,292,303. U.S. Pat. No. 4,077,407 and the foregoing patents also disclose a variety of specific systemically active agents which may also be useful in transdermal delivery, which disclosures are hereby incorporated herein by this reference.
Typical inert carriers which may be included in the foregoing dosage forms include conventional formulating materials, such as, for example water, isopropyl, alcohol, gaseous fluorocarbons, ethyl alcohol, polyvinyl pyrrolidone, propylene glycol, fragrances, gel-producing materials such as "Carbopol", stearyl alcohol, stearic acid, spermaceti, sorbitan monooleate, "Polysorbates", "Tweens", sorbital, methylcellulose, etc.
Systemically active agents are used in amounts calculated to achieve and maintain therapeutic blood levels in a human or animal over the period of time desired. These amounts vary with the potency of each systemically active substance, the amount required for the desired therapeutic or other effect, the rate of elimination or breakdown of the substance by the body once it has entered the bloodstream and the amount of penetration-enhancer in the formulation. In accordance with conventional prudent formulating practices, a dosage near the lower end of the useful range of a particular agent is usually employed initially and the dosage increased or decreased as indicated from the observed response, as in the routine procedure of the physician.
The amount of penetration enhancer which may be used in the invention varies from about 1 to 100 percent although adequate enhancement of penetration is generally found to occur in the range of about 1 to 10 percent by weight of the formulation to be delivered without localized irritating or allergic effects on the skin or other body membrane. The non-toxic penetration enhancer disclosed herein may be applied in combination with the active agent or may be applied separately to the skin or other body membrane though which the systemically-active agent is intended to be delivered as long as the non-toxic penetration enhancer and systemically active agent are together on the skin or other body membrane.
The invention is further illustrated by the following examples which are illustrative of a specific mode of practicing the invention and is not intended as limiting the scope of the appended claims.
EXAMPLE 1
A composition, in the form of a gel, suitable for transdermal delivery of haloperidol, an antidyskinetic or antipsychotic drug, is prepared by mixing the following components in the given concentration:
______________________________________Component Weight %______________________________________Haloperidol 1-51-n-Dodecylazacycloheptan-2-one 1-10Carbopol 934 P 0.5-2(Available from B. F. Goodrich)Neutralizing Agent (NaOH) q.sTween-20 1-10(Available from Atlas Chemical,a Div. of I.C.I.)Preservative (Sorbic Acid) q.s.Antioxidant (Ascorbic Acid) q.s.Chelating Agent (Disodium salt q.s.of ethylenediaminetetra aceticacid)Deionized Water q.s. to 100______________________________________
This composition is topically applied to the skin or mucosal membrane of a human subject and after the passage of a suitable period of time, haloperidol is found in the blood-stream of said subject, and no localized irritating or allergic effects on the skin or mucosal membrane are observed.
EXAMPLE 2
When an amine, e.g., triethylamine or triethanolamine, is substituted for NaOH, the results are substantially similar; i.e., a topical composition suitable for transdermally delivering haloperidol to the bloodstream is obtained without localized irritation or allergic effects on the skin or mucosal membrane.
EXAMPLE 3
When potassium sorbate or a lower alkyl paraben, e.g., methyl, ethyl propyl, or butyl paraben, is substituted for the preservative of the composition of Example 1, the results are substantially similar, i.e., a topical composition suitable for the transdermal delivery of haloperidol to the bloodstream is obtained without localized irritation or allergic effects on the skin or mucosal membrane.
EXAMPLE 4
When ascorbyl palmitate, Vitamin E, thioglycerol, thioglycolic acid, sodium formaldehyde sulfoxylate, BHA, BHT, propyl gallate or sodium metabisulfite are substituted for the antioxidant of the composition formulated in Example 1, the results are substantially similar in that a topical composition suitable for transdermally delivering haloperidol to the bloodstream is obtained without localized irritation or allergic effects on the skin or mucosal membrane.
EXAMPLE 5
The composition of Example 1 is prepared in the form of a sodium alginate gel by mixing the following components in the following given concentrations:
______________________________________Component Weight %______________________________________Haloperidol 1-51-n-Dodecylazacycloheptan-2-one 1-10Sodium Alginate 0.5-5Calcium Salts q.sTween-20 1-10Preservative* q.s.Antioxidant** q.s.Chelating Agent*** q.s.Deionized Water to 100______________________________________ *Suitable preservatives are those used in Example 3 as well as sorbic acid. **Suitable antioxidants are those used in Example 4 including ascorbic acid. ***The chelating agent is the disodium salt of ethylenediaminetetraacetic acid.
This composition when applied topically is found to transdermally deliver haloperidol to the bloodstream of a subject without localized irritation or allergic effects on the skin or mucosal membrane.
EXAMPLE 6
The composition of Example 1 is prepared in the form of a hydrophilic cream by mixing the following components.
______________________________________Component Weight %______________________________________Oil PhaseCetyl Alcohol 5-15Stearyl Alcohol 1-101-n-Dodecylazacycloheptan-2-one 0.5-10Glycerol Monostearate 2-7Water PhaseSodium Laurylsulfate 0.1Solvent* 2-20Tween-20 1-5Water q.s. to 100______________________________________ *Suitable solvents are propylene glycol, glycerin, alcohols (for example, ethyl alcohol, isopropyl alcohol, etc.) and polyethylene glycols.
The oil phase and the water phase are made up separately and then agitated to form an emulsion. (When, as in Example 8, the active ingredient is other than haloperidol, depending on its lipophilicity, it will be distributed in the oil or water phase.) This hydrophilic cream, applied topically to the skin or mucosal membrane of a human, transdermally delivers haloperidol into the bloodstream without localized irritation or allergic effects on the skin or mucosal membrane.
EXAMPLE 7
The composition of the instant invention may also be delivered by use of a polymeric matrix. For example, a solid polymer such as cellulose triacetate, polyvinyl acetate, terpolymers and copolymers of polyvinyl alcohol and polyvinyl acetate, and silicon elastomers is imbibed with a liquid having the following components in the given concentrations:
______________________________________Component Weight %______________________________________Polymer 5-40Haloperidol q.s.1-n-Dodecylazacycloheptan-2-one 0.5-80Solvent* 5-90Surfactant** 1-10Preservative*** q.s.Antioxidant**** q.s.______________________________________ *Solvents may be the solvents used in Example 6 above. **The Surfactant may be Tween20, glycerol monostearate or sodium laurylsulfate, etc. ***The preservative may be any of the preservatives used in Example 3 above. ****The antioxidants may be any of those used in Example 4 above.
When solid matrix, containing the active ingredients formulated above, is contacted with the skin or mucosal membrane of a human subject, after a period of time the active agent is found in the bloodstream of said subject without localized irritation or alergic effects on the skin or mucosal membrane.
EXAMPLE 8
Examples 1 to 7 are repeated except that the following active ingredients in the given concentrations are substituted for haloperidol:
______________________________________Active Ingredient Weight %______________________________________Isosorbide Dinitrate 5-15Nitroglycerin 1-5Estradiol 1-5Clonidine 0.5-3Propranolol 1-5Indomethacine 5-15Nifedipine 1-5Nicardipine 1-5Diclorofenac 5-15Metaproterenol 1-5______________________________________
EXAMPLE 9
Examples 1 to 8 are repeated except that the compounds exemplified on pages 5-6 (except for 1-n-Dodecylazacycloheptan-2-one) are substituted for 1-n-Dodecylazacycloheptan-2-one. Similar results are obtained in that the active ingredients are transdermally delivered to the bloodstream of an animal without localized irritation or allergic effects on the skin or mucosal membrane.
While particular embodiments of the invention have been described, it will be understood of course that the invention is not limited thereto since many obvious modifications can be made; and it is intended to include without this invention any such modifications as will fall within the scope of the appended claims. | This invention relates to a method for administering systemically active agents, including therapeutic agents, through the skin or mucosal membranes of humans and animals in a transdermal device or formulation comprising topically administering with said systemic agent a non-toxic, effective, penetrating amount of a membrane penetration enhancer having the structural formula ##STR1## wherein X represents sulfur or two hydrogen atoms; R' is H or a lower alkyl group having 1-4 carbon atoms; m is 2-6; n is 0-18 and R is --CH 3 , ##STR2## wherein R" is H or halogen. | 8 |
BACKGROUND OF THE INVENTION
1. Field of Invention
The present invention relates to a drain plug, more particular to a captive drain plug assembly that has an interesting appearance.
2. Description of the Related Art
A conventional drain plug closes a drain of a sink. Many types of drain plugs exist, and some conventional drain plugs have interesting appearances for fun. With reference to FIG. 6 , a conventional drain plug ( 60 ) selectively closes a drain ( 70 ) and comprises a stopper ( 61 ) and a decorative knob ( 62 ). The stopper ( 61 ) is removably mounted in the drain ( 70 ) and has a top surface and a mounting recess ( 611 ). The mounting recess ( 611 ) is defined in the top surface of the stopper ( 61 ) and has an annular recess. The decorative knob ( 62 ) has a bottom and a connector ( 621 ). The connector ( 621 ) is formed on and protrudes from the bottom of the decorative knob ( 62 ), is mounted in the annular recess ( 611 ) and has an annular lip. The annular lip is formed around the connectors, corresponds to and is selectively mounted in the annular recess in the mounting recess ( 611 ).
When the conventional drain plug ( 60 ) is removed from a drain ( 70 ), the decorative knob ( 62 ) pulls out of the stopper ( 61 ), and the stopper ( 61 ) does not come out of the drain ( 70 ). Furthermore, the entire plug ( 60 ) is easily lost when removed from the drain ( 70 ).
The drain plug in accordance with the present invention obviates or mitigates the aforementioned problems.
SUMMARY OF THE INVENTION
The primary objective of the present invention is to provide a drain plug assembly that a stopper that cannot be removed completely from a drain easily and has an aesthetically appealing appearance.
To achieve the objective, a captive drain plug assembly is securely attached to a drain trap and has a mounting anchor, a sleeve and a decorative stopper. The mounting anchor is mounted inside the drain trap. The sleeve mounted slidably on the mounting anchor. The decorative stopper is attached to the sleeve. When the drain plug is used, the decorative stopper will not detach from the mounting anchor. Further, the decorative stopper can be formed as an interesting figure to increase fun when the decorative stopper is used.
Other objectives, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded perspective view of a drain plug assembly in accordance with the present invention;
FIG. 2 is a side view in partial section of the drain plug assembly in FIG. 1 when a decorative stopper and a sleeve is attached to a mounting anchor connected to a drain trap;
FIG. 3 is a side view in partial section of the drain plug assembly in FIG. 1 when the decorative stopper is pressed down;
FIG. 4 is a side view in partial section of the drain plug assembly in FIG. 1 when the decorative stopper is pulled up;
FIG. 5 is a side view in partial section of a second embodiment of the drain plug assembly in accordance with the present invention; and
FIG. 6 is an operational side view in partial section of a conventional drain plug in accordance with the prior art.
DETAILED DESCRIPTION OF THE INVENTION
With reference to FIGS. 1 and 2 , a drain plug assembly in accordance with the present invention is mounted in a drain trap ( 10 ) and has a mounting anchor ( 20 ), a sleeve ( 30 ) and a decorative stopper ( 40 ).
The drain trap ( 10 ) is adapted to be mounted in a drain pipe and has a center, a top edge, a bottom, a cavity, a mounting hole ( 12 ) and an annual lip ( 13 ). The cavity is formed in the center of the drain trap ( 10 ) from the top edge to the bottom and has an open top and a partially open bottom. The mounting hole ( 12 ) is defined in the center of the body ( 10 ) at the partial open bottom. The annual lip ( 13 ) is formed at and extends outwardly from the top edge of the drain trap ( 10 ).
The mounting anchor ( 20 ) is mounted in the mounting hole ( 12 ) in the drain trap ( 10 ) and has a post ( 200 ) and a head ( 21 ).
The post ( 200 ) is mounted in the mounting hole ( 12 ) and has a top end, a bottom end, a side surface and a limiting device. The bottom end is mounted in the mounting hole ( 12 ) in the drain trap ( 10 ). In a preferred embodiment, the bottom end is threaded and is screwed into the mounting hole ( 12 ) in the drain trap ( 10 ). The limiting device is on the side surface of the post ( 200 ). In a preferred embodiment, the limiting device has two recesses ( 23 ), a bracing piece ( 24 ), two optional limit slots ( 25 ) and a resilient body ( 26 ). The recesses ( 23 ) are defined in the side surface, and each recess ( 23 ) has a bottom corner. The bracing piece ( 24 ) is formed between the recesses ( 23 ) and forms a mounting slot ( 241 ) that communicates with the recesses ( 23 ). The limit slots ( 25 ) are defined respectively in the bottom corners of the recesses ( 23 ). The resilient body ( 26 ) is mounted in the mounting slot ( 241 ) and has two optional legs ( 261 ). The resilient body ( 26 ) is mounted in the mounting slot ( 241 ), and the legs ( 261 ) are mounted respectively in the limited slots ( 25 ).
The head ( 21 ) has a top, a conical hook ( 210 ) and a slot ( 211 ). The conical hook ( 210 ) is formed on the top of the head ( 21 ), and the slot ( 211 ) is defined longitudinally in the head ( 21 ).
The sleeve ( 30 ) is mounted on the mounting anchor ( 20 ) and has a top edge, an inner surface, a lip ( 31 ), an inner shoulder ( 34 ) and an optional tube ( 35 ). The lip ( 31 ) is formed on and extends out from the top edge. The inner shoulder ( 34 ) is defined in the inner surface, and the tube ( 35 ) is mounted inside the inner surface of the sleeve ( 30 ).
The decorative stopper ( 40 ) is mounted on the sleeve ( 30 ) and has a plug ( 43 ), a decorative knob ( 42 ) and a seal ( 41 ). The plug ( 43 ) has a top, a bottom, a top edge, an inner surface, a cavity ( 44 ) and an annual recess ( 45 ). The cavity ( 44 ) is defined in the plug ( 43 ). The annual recess ( 45 ) is defined in the inner surface near the bottom, communicates with the cavity ( 44 ) and holds the lip ( 31 ) of the sleeve ( 30 ). The decorative knob ( 42 ) is formed on the top of the plug ( 43 ) and may be formed as an interesting character. The seal ( 41 ) is formed on the top edge of the plug ( 43 ) and extends out radially.
With reference to FIGS. 3 and 5 , the decorative stopper ( 40 ) is pressed down to seal the drain trap ( 10 ), and the head ( 21 ) of the mounting anchor ( 20 ) moves into the cavity ( 44 ) in the decorative stopper ( 40 ), and the seal ( 41 ) overlaps the annular lip ( 13 ) on the drain trap ( 10 ) to form a watertight seal. The sleeve ( 30 ) is pressed down onto the resilient body ( 26 ), and the legs ( 261 ) of the resilient body ( 26 ) are pressed inside the limit slots ( 25 ).
With reference to FIG. 4 , the decorative stopper ( 40 ) is pulled up to open the drain trap ( 10 ), and the head ( 21 ) on the mounting anchor ( 20 ) engages the inner shoulder ( 34 ) of the sleeve ( 30 ). The legs ( 261 ) of the resilient body ( 26 ) press against the inner surface of the sleeve ( 30 ) to hold the decorative stopper ( 40 ) up and prevent the drain trap ( 10 ) from being closed again.
The drain plug assembly has the following advantages.
1. The decorative stopper is attached securely to the mounting anchor and does not release from the mounting anchor easily.
2. The decorative knob is formed as an interesting character to increase enjoyment.
The invention may be varied in many ways by a person skilled in the art. 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. | A captive drain plug assembly is securely attached to a drain trap and has a mounting anchor mounted inside the drain trap, a sleeve mounted slidably on the mounting anchor and a decorative stopper attached to the sleeve. When the drain plug is used, the decorative stopper will not detach from the mounting anchor. Further, the decorative stopper can be formed as an interesting figure to increase fun when the decorative stopper is used. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a system for generating and rapidly changing the time delays of electrical signals for true time delay beam formation and steering.
2. Description of Related Art
The use of wide aperture, wide bandwidth phase steered array antennas for transmitting and receiving wideband signals is a known technique. Such known antennas suffer from a problem of beam dispersion or broadening when steering away from the array normal.
Attempts have been made to avoid this problem of beam dispersion through the use of time delays between the array elements. One approach for implementing true time delay beam formation is to switch in different lengths of signal transmission delay lines between the common signal source and the antenna array elements. This known approach tends to be bulky and cumbersome for scanning an array with a large number of array elements over a wide range of nearly continuous angles.
It is an object of the present invention to provide a system that is simple and that does not require a bulky and complex implementation.
It is a further object of the present invention to provide a system for implementing true time delay beam formation that may fit into a small lightweight package, that is relatively rugged, and that consumes relatively small amounts of power.
SUMMARY OF THE INVENTION
In accordance with the present invention, these and other objectives are achieved by providing a system in which time delays may be generated by using an acousto-optic (AO) Bragg cell as a continuous tapped delay line. Selected points in the Bragg cell may be optically mapped to the output. The optical mapping may be controlled using additional optical and acousto-optical devices. The optical mapping may make use of prisms and/or holographic optical elements, in addition to other standard passive optical elements.
A system in accordance with the present invention is capable of generating and rapidly changing time delays for true time delay beam formation and steering. A system in accordance with the present invention enables a time delay beam formation array to simultaneously scan multiple beams rapidly over a continuum of angles.
A system in accordance with the present invention may be used, for example, in airborne reconnaissance and surveillance, space-based radar, satellite communications, or large space-based arrays, where size, weight and power are major considerations.
A system in accordance with the present invention does not require a bulky and complex implementation. The hardware required to implement a true time delay beam formation system in accordance with the present invention may fit into a small lightweight package, may be rugged, and may consume relatively small amounts of power. The simplicity and compactness of the system dramatically reduces unwanted variability in the relative time delays.
BRIEF DESCRIPTION OF THE DRAWINGS
A detailed description of a preferred embodiment of the present invention will be made with reference to the accompanying drawings.
FIG. 1 shows an example of an acousto-optic system for generating a time delay for a one-dimensional transmitting array.
FIG. 2 shows an example of an acousto-optic system for generating a signal time delay.
FIG. 3 shows an example of a reference wave on a photodiode.
FIG. 4 shows an example of an acousto-optic system for generating a time delay for a two-dimensional transmitting array.
FIG. 5 shows an example of an acousto-optic system for generating a time delay for a one-dimensional receiving array.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following detailed description is of the best presently contemplated mode of carrying out the invention. This description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention. The scope of the invention is best defined by the appended claims.
FIG. 1 shows an example of an acousto-optic system 10 for generating time delays for a one-dimensional transmitting array. The skilled artisan will recognize a resemblance between the system 10 shown in FIG. 1 as a Mach-Zehnder interferometer.
The signal to be transmitted may be represented by s(t), where the complex amplitude of the signal s is a function of time t. The signal s(t) drives an acousto-optic Bragg cell 12 located in a first leg 14 of the interferometer system 10. Coherent light from a laser source 16 may be passed through the Bragg cell 12 and may be modulated by the signal s(t).
A Fourier transform lens 18 may also be provided in the first leg 14 of the interferometer system 10. Light that is passed through the Fourier transform lens 18 is separated into a spectrum. Modulated light exiting from the Bragg cell 12 may be passed through the Fourier transform lens 18, thereby causing the spectrum of the modulated light signal to illuminate an array 20 of wideband photodiodes 22. In the system illustrated in FIG. 1, the photodiode array 20 is preferably located in the Fourier transform plane of the first Bragg cell 12.
Each of the photodiodes 22 in the photodiode array 20 is preferably narrower in one dimension and wider in another dimension. As shown in FIG. 1, for example, each of the photodiodes 22 is narrower in the vertical dimension and wider in the horizontal dimension. The width of each photodiode 22 is preferably large enough to capture the full spectrum of the modulated light signal illuminating the photodiode.
The interferometer system 10 illustrated in FIG. 1 also includes a beam splitter 24. The beam splitter 24 splits the coherent light from the laser source 16 into a first leg 14 and a second leg 26.
The second leg 26 includes a second Bragg cell 28. A beam steering signal may be inserted into the second Bragg cell 28. For a single beam, the beam steering signal may be in the form of a sine wave. For forming and steering multiple beams, multiple sine waves may be used.
The second leg 26 of the interferometer system 10 may also be provided with a stack of prisms 30. The stack of prisms 30 performs the function of creating, from the output of the second Bragg cell 28, a set of plane reference waves having a range of orientations required to generate a desired range of time delays.
More specifically, the prism stack 30 performs the function of taking an input beam from the second Bragg cell 28 at incidence angle θ' and producing multiple output beams at angles θ proportional to θ'. For example, if the input angle is θ', then the output angles would be aθ'+k, bθ'+k, cθ'+k, etc. The prism stack 30 thereby performs the function of mapping a single angle into multiple angles. The difference between successive output angles of the prism stack 30 is a function of the input angle θ', thereby producing variable differential time delays.
Alternatively, the prism stack 30 may be replaced by a holographic optic element. Such a holographic optic element would similarly perform the function of creating, from the output of the second Bragg cell 28, a set of plane reference waves having a range of orientations required to generate a desired range of time delays. In the two dimensional system shown in FIG. 4, for example, the volume hologram 150 performs substantially the same function as the prism stack 30 in the one-dimensional system shown in FIG. 1. Prisms or volume hologram elements may be used for beam formation in antennas having array elements arranged linearly, as well as antennas having array elements lying along a curve.
Referring to FIG. 1, the optics in the second leg 26 are preferably arranged so that there is a one-to-one correspondence between the photodiodes 22 of the photodiode array 20 and the prisms of the prism stack 30, whereby each photodiode 22 in the photodiode array 20 is illuminated by a reference plane wave output of a corresponding prism of the prism stack 30.
The interferometer system 10 illustrated in FIG. 1 is arranged so that the signal spectrum associated with the first leg 14 and the reference plane wave associated with the second leg 26 interfere at the photodiode array 20. Each of the photodiodes 22 detects the interference between the signal spectrum and the reference plane wave. Each of the photodiodes 22 produces an output signal that corresponds to the detected interference, integrated over the width of the photodiode. Since the width of each photodiode 22 is preferably large enough to capture the full signal spectrum, the integration occurs over the full spectral frequency.
The output signal of each of the photodiodes 22 corresponds to a delayed replica of the input signal. The amount of the delay is determined by the angle between the reference plane wave and the surface of the photodiode 22.
The output of the photodiode array 20 may be sent to a linear transmitting array (not shown). In a preferred embodiment, there is a one-to-one correspondence between each photodiode 22 of the photodiode array 20 and each element of the transmitting array.
The following paragraphs provide a mathematical description of how a system such as that shown in FIG. 1 may generate variable time delays.
As shown in FIGS. 2 and 3, a reference plane wave makes an angle θ with the surface of a photodiode 22. The reference plane wave at the surface of the photodiode 22 may be represented mathematically by: ##EQU1## where y represents the physical distance along the photodiode 22, λ represents the optical wavelength of the reference plane wave, f o represents the optical carrier frequency of the reference plane wave, and c represents the velocity of light. The spectral frequency f of the signal in the Fourier transform plane is proportional to the physical distance y along the photodiode 22. Therefore, a factor τ,having units of time, may be defined such that: ##EQU2## As indicated in Equation (2), the factor τ is proportional to sin(θ). The reference plane wave at the photodiode may therefore be expressed as,
r(t,f)=e.sup.j2πfτ e.sup.j2πf.sub.o.sup.t (3)
In the first leg 14 of the interferometer system 10, a coherent optical beam, modulated and Doppler shifted by the frequency component S(f) of the signal, also illuminates the photodiode 22. At the photodiode 22 this modulated coherent beam has the following functional form:
S(f)·e.sup.j2πft e.sup.j2πf.sub.o.sup.t (4)
The oscillators,
e.sup.j2πft TM (5)
result from the fact that each frequency component of the signal in the first Bragg cell 12 Doppler shifts the optical carrier by the frequency of that component.
To negate the Doppler shift of the steering signal, a point modulator may be placed in the second leg 26 of the interferometer system to downshift the frequency of the optical beam by the frequency of the steering signal. This Doppler shift could also be removed electrically at the photodiode output.
The sum of the beams illuminating the photodiode may be square-law detected using the photodiode. The output d(t) of the photodiode at each instant of time is equal to the square-law detection integrated along the length of the photodiode (i.e., integrated with respect to the frequency f): ##EQU3## Consequently, the photodiode output d(t) may be represented as,
d(t)=bias+2Real[s(t-τ)] (7)
As indicated in Equation (7), the photodiode output d(t) is equal to the input signal s(t) delayed by a time τ.
The delay time τ is proportional to the sine of the angle of incidence of the reference plane wave on the photodiode. The bias allows negative and positive values of the delayed signal to be represented.
A physical explanation of how an acousto-optic system (as shown, for example, in FIGS. 1, 2 and 3) can produce an output signal that is a delayed replica of the input signal, with the amount of the delay being determined by the angle of incidence of the reference plane wave on the photodiode, is as follows:
Since the photodiode coherently sums all of the frequency components of the signal s(t), only those components of the spectrum that are in phase with one another, after being phase shifted by the reference signal, will lead to a significant output signal relative to the bias. Since the reference signal is a plane wave, the component of the signal spectrum, in optical form, that contributes to an output signal must also be a plane wave if, after being phase shifted by the reference signal, all points on the photodiode are to be at the same phase. Referring to FIG. 1, for example, components of the optical signal that contribute to a plane wave in the Fourier plane (at the photodiode array 20) come from a single point in the Bragg cell 12. Thus, the reference wave selects which point in the Bragg cell 12 (a delay line) is mapped to the output. The angle of the reference wave determines the delay of the output signal relative to the input signal.
The systems described above relate generally to systems for generating a time delay for a one-dimensional transmitting array. In the above-described systems, the photodiode array is preferably located in the Fourier transform plane of the first Bragg cell. Time delays may also be generated by placing the photodiode array in the image plane of the first Bragg cell. Placement of the photodiode array in the image plane of the first Bragg cell is particularly appropriate for two-dimensional array beam formation.
FIG. 4 shows an example of a system 110 for generating time delays of a signal for forming and steering the beam of a two-dimensional (planar) array. The skilled artisan will recognize a resemblance between the system 110 shown in FIG. 4 and a Mach-Zehnder interferometer.
In the system 110 illustrated in FIG. 4, time delays may be generated by placing a photodiode array 120 in an image plane of a first Bragg cell 112 and optically mapping points in the first Bragg cell 112 onto the photodiode array 120. The electrical outputs of the photodiode array 120 are time delayed replicas of the signal s(t). These time delayed replicas of the signal s(t) are then sent to the elements of the planar array.
In the system 110 for a two-dimensional transmitting array shown in FIG. 4, each of the photodiodes in the photodiode array 120 sees only the image of a single point in the first Bragg cell 112. Consequently, both the vertical and horizontal dimensions of each photodiode in the photodiode array 120 are preferably relatively small. In contrast, in the system 10 for a one-dimensional transmitting array shown in FIG. 1, the photodiode array 20 is preferably located in the Fourier transform plane of the first Bragg cell 12. The width of each photodiode 22 in the photodiode array 20 is preferably large enough in the horizontal dimension to capture the full spectrum of the modulated light signal illuminating the photodiode.
As shown in FIG. 4, a collimated coherent laser beam from a laser source 116 is divided into a first leg 114 and a second leg 126 by a beam splitter 124. The optical beam passing through the second leg 126 provides a reference at the photodiode array 120 for heterodyne detection, so that the voltages from the electrical signals out of the photodiode array 120 are proportional to the voltages of the time delayed replicas of the input signal to the device. Although the embodiment illustrated in FIG. 4 shows a reference beam generated by a beam splitter 124, it is noted that neither the reference beam nor the beam splitter are required elements of the invention. For example, a reference beam may be provided by a separate coherent light source. Alternatively, if the signal to be delayed is of an on-off modified type, then no reference beam may be required.
In the first leg 114 the input electrical signal s(t), the signal to be transmitted by the RF planar array, drives the first acousto-optic Bragg cell 112. The result is that the first Bragg cell 112 which is a delay line contains a time span of the signal, in acoustic form, from time t-T a to time t, where T a represents the time aperture of the first Bragg cell 112. The coherent laser beam passing through the first Bragg cell 112 may be modulated by the signal and Fourier transformed by a first lens 140. Points in the first Bragg cell 112 are plane waves at a second Bragg cell 142 and a third Bragg cell 144. The angular orientations of the plane waves are determined by the positions of the points in the first Bragg cell 112.
The mapping of points in the first Bragg cell 112 to the photodiode array 120 is controlled by the frequencies of a vertical electrical signal v(t) and a horizontal electrical signal h(t) that drive the second Bragg cell 142 and the third Bragg cell 144. Both the vertical signal v(t) and the horizontal signal h(t) are preferably sine waves. The signal in the second Bragg cell 142 changes the angular orientation of the plane waves passing through the second Bragg cell with respect to vertical. The signal in the third Bragg cell 144 changes the angular orientation of the plane waves passing through the third Bragg cell with respect to horizontal.
The positions and focal lengths of a second lens 146 and a third lens 148 are such that the volume hologram 150 is also in the Fourier transform plane of the first Bragg cell 112, so that points in the first Bragg cell 112 are plane waves in the volume hologram. The volume hologram 150 is also approximately in the image planes of the second Bragg cell 142 and the third Bragg cell 144. Therefore, the vertical signal v(t) and the horizontal signal h(t) control the angular orientation of the plane waves at the volume hologram 150.
The volume hologram 150 is constructed such that the plane waves at the volume hologram (points in the first Bragg cell 112) are mapped into points on the photodiode array 120. The mapping is determined by the angular orientation of the plane waves at the volume hologram 150. The mapping of points in the first Bragg cell 112 onto the photodiode array 120, and therefore the steering angle of the planar array, is controlled by the vertical signal v(t) and the horizontal signal h(t).
A large set of point-to-point mappings may be required to generate the different time delays necessary for pointing an RF planar array in a large number of directions. Referring to FIG. 4, for example, the mapping of points from the first Bragg cell 112 is not required to be one-to-one for a planar array. For each orientation of the beam, some number of points in the Bragg cell 112 may be mapped to a larger number of photodiodes in the photodiode array 120.
FIG. 5 shows an example of an acousto-optic system 210 for generating a time delay for a one-dimensional receiving array. To form a beam in a particular direction with a receiving linear RF array, the outputs of the array elements must be delayed relative to one another and then summed. The amount of relative delay between the array elements may be determined by the spacing between the array elements and by the angle between the beam and the normal to the linear array.
The principle of how the system 210 illustrated in FIG. 5 delays a signal is essentially the same as for the system 10 for a one-dimensional transmitting array as shown in FIG. 1. In a first leg 214 of the system 210 illustrated in FIG. 5 a multi-channel Bragg cell 212 is used. The number of channels of the Bragg cell 212 is preferably equal to the number of antenna elements in the linear array. An electrical signal from each element of the receiving array drives a channel of the multi-channel Bragg cell 212. The signal in a channel of the multi-channel Bragg cell 212 is optically Fourier transformed onto a corresponding photodiode 222. As previously described herein, the electrical output of the photodiode 222 is a time delayed replica of the electrical signal that drives the corresponding channel of the multi-channel Bragg cell 212. The time delay may be determined by the angle between the reference plane wave from a second leg 226 of the illustrated system 210 and the face of the photodiode 222.
the second leg 226 of the illustrated system 210 functions substantially identically to the second leg 26 in the system 10 shown in FIG. 1 to generate time delays for transmitting a signal with a one-dimensional array. A stack of prisms 230 in the second leg 226 results in reference plane waves having a distribution of angles incident on the photodiode array 220. This allows a single channel Bragg cell 228, preferably driven with sine waves, to control a range of time delays.
The electrical outputs of the photodiodes 222 may be summed electrically. This sum is the signal arriving at the linear array from the direction determined by the frequency of the steering signal driving the Bragg cell 228 in the second leg 226 of the illustrated system 210.
The system shown in FIG. 5 may also be used for the formation and steering of beams for two-dimensional (planar) receiving arrays.
The projection of a pointing direction of a receiving array is a straight line on the face of the array. The time delays are all the same on each line on the array that is normal to this projection of the beam pointing direction. Therefore, to form a beam with a planar receiving array using the system shown in FIG. 5, the outputs of the array elements that lie along the lines normal to the projection of the desired beam pointing direction may first be summed electrically, one sum for each line. The spacing between the lines is approximately equal to the spacing between the antenna array elements that lie along the projection of the beam pointing direction onto the face of the antenna. The electrical sums may then be used to drive the channels of the channeling AO Bragg cell 212 shown in FIG. 5. The steering signal in this case determines the angle of the formed beam with respect to the normal to the face of the array.
The electrical outputs of the antenna array elements may be phase shifted before summing to compensate for the small deviations of positions of the array elements from the lines normal pointing direction.
The presently disclosed embodiments are to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims, rather than the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. | Optical systems are disclosed which are capable of generating and rapidly changing time delays of electrical signals for true time delay beam formation and beam steering. The systems utilize an interferometer configuration. A first optical modulator and a Fourier transform lens define a Fourier transform plane in a first leg of the interferometer. In a second leg of the interferometer, a second optical modulator provides beam steering to a prism stack, which produces a set of plane reference waves having a range of orientations required to generate a desired range of time delays. Preferably the optical modulators are acousto optic Bragg cells. Alternatively, a holographic optic element could be used in place of the prism stack. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a divisional of application of U.S. patent application Ser. No. 10/671,660 filed on Sep. 29, 2003 and now U.S. Pat. No. 7,032,350 B2; which is a divisional of U.S. patent application Ser. No. 09/878,947 filed on Jun. 13, 2001 and now U.S. Pat. No. 6,665,984.
BACKGROUND OF THE INVENTION
The invention is directed to a door or lid which is normally hinged to a washer opening to define a top-loading or a front-loading washer. Conventionally such doors or lids have been made of metal with or without a glass panel through which the interior of the washer can be viewed.
DESCRIPTION OF THE RELATED ART
U.S. Pat. No. 4,695,420 granted on Sep. 22, 1987 and assigned to Caterpillar, Inc. makes reference to the desirability of injection molding plastic articles having a variety of complex shapes and sizes including panels and doors of vehicles or equipment enclosures, such as cab doors. Such cab doors were originally manufactured by utilizing a flat rigid frame fabricated from metal to which is unitized a window in what is termed a costly and time-consuming operation. The window or glazing is floated in a soft gasket channel isolated from the frame to reduce shock-loads and thermal stresses induced by varying coefficients of thermal expansion between the metal frame and the glazing/glass panel. It is believed that the process just described is workable because the window panes in all cases are sheets of transparent plastic material, such as polycarbonate and acrylic with the preferred material being a polycarbonate having a silicone hard coat applied thereto to make the polycarbonate glazing or window pane more scratch-resistant. The silicone hard coat on the peripheral edge is removed by sanding or grinding to assure good bonding between the eventually molded frame and the polycarbonate glazing.
With the advent of excellent molding qualities of modem plastic materials, an effort was made to form a door by first manufacturing a pre-shaped pane of transparent glass and subsequently integrally molding the latter into a door frame as the window thereof. Following this process, the window pane was distorted and wavy and the door frame had a tendency to warp. However, by utilizing a high modulus plastic material, such as polyurethane and a shrink-reducing filler material, undesired high temperature rise from exothermic reaction was moderated, particularly when a catalyst was added in sufficient amounts to control the weight of the reaction and the heat evolution. Also, by heating the glass and forming the frame by reaction injection molding, both the frame and the glass window pane thermally contract similarly absent window pane buckle and with bonding of the edges of the glass window pane to the frame.
Glass and specifically tempered glass have heretofore never been provided with an injection molded polymeric/copolymeric frame to form a door or lid, and particularly a washer lid. However, injection-molding polymeric/copolymeric material as an encapsulation or border to form a shelf is well known, as is evidenced by U.S. Pat. No. 5,273,354 granted on Dec. 28, 1993; U.S. Pat. No. 5,362,145 granted on Nov. 8, 1994; U.S. Pat. No. 5,403,084 granted on Apr. 4, 1995; U.S. Pat. No. 5,429,433 granted on Jul. 4, 1995; U.S. Pat. No. 5,441,338 granted on Aug. 15, 1995; U.S. Pat. No. 5,454,638 granted on Oct. 3, 1995; U.S. Pat. No. 5,540,493 granted on Jul. 30, 1996 and U.S. Pat. No. 5,735,589 granted on Apr. 7, 1998.
Other patents dealing with glass to which material is injection molded normally include windshields to which a gasket is molded and/or cured in situ so as to encapsulate a marginal peripheral edge of the windshield. Typical of such window assemblies and methods of forming the same are found in such patents as U.S. Pat. No. 4,778,366 granted on Oct. 18, 1998; U.S. Pat. No. 4,688,752 granted on Aug. 25, 1987 and U.S. Pat. No. 4,732,553 granted on Mar. 22, 1988.
Other patents which were located during the search of the instant invention include U.S. Pat. No. 4,543,283 granted on Sep. 22, 1987; U.S. Pat. No. 3,843,982 granted on Oct. 29, 1974; U.S. Pat. No. 6,146,574, granted on Nov. 14, 2000 and U.S. Pat. No. 4,336,301 granted on Jun. 22, 1982.
SUMMARY OF THE INVENTION
The present invention is specifically directed to a door or lid for a washer, but contrary to the door of U.S. Pat. No. 4,695,420, the transparent panel is constructed from tempered glass and an open frame-like encapsulation is preferably a polymeric/copolymeric synthetic plastic material in the form of acrylonitrile/styrene/acrylate polymer blended with mica glass beads at a ratio of substantially 70%-30% to 90%-10% by weight, but preferably 80%-20% by weight. The latter specifics of the blended material which is injection molded to form the open frame-like encapsulation achieves a much lower shrink ratio and elasticity, as compared to polypropylene which is normally used in the injection molding of a tempered glass substrate to form a shelf (not a door). Since tempered glass or a similar glass substrate has virtually a zero coefficient of expansion, the same obviously will not expand or contract in relationship to the expansion or contraction of conventional polymeric/copolymeric material, such as polypropylene. Consequently, typical “weld lines” created in the injection molded open frame-like encapsulation or border tend to fracture, particularly as such parts experience temperatures varying between −30° F. to +104° F. However, through the utilization of the specific blended materials latter defined at the ratios stated, such fracture has been essentially eliminated and the washer door or lid of the present invention achieves unexpected longevity, absent deterioration, and aesthetic characteristics at competitive prices, particularly at higher price-ranged washers.
The aesthetics of the washer lid are also enhanced by designing the exterior of the frame-like encapsulation which is exposed to the consumer as a relatively smooth, unbroken surface except as might otherwise be desired by a washer manufacturer who might specify a recess in the outer surface for reception of a decal, label or the like carrying trademark or other information. The interior of the washer lid which is less susceptible to scrutiny because of it being opened essentially only when the washer is being loaded or unloaded is engineered to include structural characteristics necessary for optimum functionality of the washer lid including, for example, an internally stepped relatively thick inner periphery of the frame-like encapsulation which securely grips and reinforces the peripheral edge of the tempered glass panel, an outboard depending peripheral skirt achieving exterior peripheral rigidity of the frame-like encapsulation, an indiscrete handle portion along an underside of a front wall of the encapsulation which is essentially unobservable when the washer lid is closed, a reinforced corner for a switch actuator, and opposite rear comers rigidly supporting hinges which are utilized to hinge the washer lid to an associated washer opening for movement between open and closed positions thereof.
With the above and other objects in view that will hereinafter appear, the nature of the invention will be more clearly understood by reference to the following detailed description, the appended claims and the several views illustrated in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmentary top perspective view, and illustrates a washer with a washer lid or door of the present invention hinged thereto in its closed position.
FIG. 2 is a fragmentary perspective view of the washer of FIG. 1 , and illustrates the washer lid in its open position.
FIG. 3 is a bottom plan view of the washer lid or door, and illustrates a tempered glass panel bonded by an open frame-like encapsulation formed of one-piece injection molded polymeric/copolymeric plastic material.
FIG. 4 is a fragmentary cross sectional view through a corner portion of two identical rear comers of the washer lid, and illustrates a generally L-shaped hinge defined by a mounting portion and a pintle portion with the former being fastened to a depending peripheral skirt of the frame-like encapsulation and the pintle portion passing through a slot of the depending peripheral skirt.
FIG. 5 is an exterior fragmentary side elevational view of the hinge of FIG. 4 , and illustrates the details thereof.
FIG. 6 is an interior fragmentary side elevational view of the hinge of FIG. 4 .
FIG. 7 is a fragmentary bottom plan view of a forward corner of the frame-like encapsulation, and illustrates a switch actuator seated upon reinforcing ribs projecting from a top panel of the frame-like encapsulation and being secured to the peripheral skirt by fasteners.
FIG. 8 is an outside fragmentary side elevational view of the forward corner illustrated in FIG. 7 , and illustrates details of the switch actuator.
FIG. 9 is a fragmentary cross sectional view of the peripheral skirt of the corner of FIG. 7 , and illustrates further details of the switch actuator.
DETAILED DESCRIPTION OF THE INVENTION
A washer 10 is illustrated in FIGS. 1 and 2 of the drawings and includes a conventional washer body 11 having an interior tub or chamber 12 including an upper frame 13 to which is hinged a novel washer lid or door 20 of the present invention. The upper frame 13 defines an upstanding inner peripheral wall 14 ( FIGS. 2 and 4 ) at opposite rear comers (unnumbered) which the upper frame 13 is provided with openings 15 ( FIG. 4 ) for hinging the washer lid 20 thereto in a manner to be described more fully hereinafter.
A conventional agitator (not shown) is mounted in the tub or chamber 12 and reciprocates arcuately in a conventional fashion. A conventional safety switch or “ON”/“OFF” switch 18 ( FIG. 2 ) is carried by and beneath an apertured horizontal frame portion 16 of the upper frame 13 of the washer 10 , and is switched “on” and “off” by the washer lid 20 in a manner to be described more fully hereinafter.
The washer lid or door 20 includes a tempered glass panel 21 of a predetermined peripheral configuration defined by a substantially continuous peripheral edge 22 . The glass panel 21 further includes opposite inner and outer surfaces 23 , 24 , respectively, bridged by the peripheral edge 22 . A peripheral portion 25 of the glass panel 21 is defined by the peripheral edge 22 and immediately adjacent surface portions of the opposite inner and outer surfaces 23 , 24 , respectively.
An open frame-like encapsulation or border 30 is formed as a one-piece of injection molded polymeric/copolymeric synthetic plastic material. The polymeric/copolymeric synthetic plastic material is preferably acrylonitrile-styrene-acrylate polymer blended with mica glass beads at a ratio of substantially 70%-90% of the polymer and substantially 30%-10% of the mica glass beads, respectively, by weight. The preferable range by weight of the blend is substantially 80% of the polymer to substantially 20% of the mica glass beads. The latter ranges of the polymer and the mica glass beads achieve an extremely low shrink ratio and elasticity, as compared to polypropylene. As the injection molded blended polymer of the open frame-like encapsulation 30 cools, its virtually minimal shrink ratio parallels the almost zero coefficient of expansion of the tempered glass panel 21 . Consequently, weld lines of the injection molded frame-like encapsulation 30 will not fracture, particularly when subject to temperature anywhere between −30° F. to 140° F.
The open frame-like encapsulation 30 includes an outer peripheral portion 31 and an inner peripheral portion 32 with the inner peripheral portion 32 entirely encapsulating the glass panel outer peripheral portion 25 including the peripheral edge 22 and immediately adjacent surface portions of the opposite inner and outer surfaces 23 , 24 , respectively. The frame-like encapsulation 30 further includes an inner or lower surface 34 and an outer or upper surface 35 defining therebetween the overall inner and outer surface configurations of the frame-like encapsulation 30 and the wall thickness thereof. The frame-like encapsulation inner surface 35 is stepped ( FIG. 2 ) at the frame-like inner peripheral portion 32 and defines thereat a relatively thicker wall thickness than the wall thickness at the outer peripheral portion 31 . However, the outer surface 34 has a configuration which is substantially continuous and unstepped which presents an aesthetic appearance to the washer lid 20 when in the closed position ( FIG. 1 ), and all remaining injection-molded characteristics are formed along the inner surface 35 and are hidden from view ( FIG. 1 ) except, of course, when the washer lid 20 is opened ( FIG. 2 ).
The outer peripheral portion 31 of the washer lid 20 is defined as continuously downward depending peripheral wall or skirt which is smooth and unbroken except along a front edge (unnumbered) of the frame-like encapsulation 30 . At the front edge ( FIGS. 1-3 ) of the frame-like encapsulation 30 a curved wall portion 38 ( FIGS. 2 and 3 ) of the depending skirt 31 is recessed inwardly and opens concavely outwardly to define a handgrip recess 40 in association with an overlying ledge or lip 39 of the frame-like encapsulation 30 . In order to open the washer lid 20 , a person merely inserts one or more fingers within the handgrip area 40 ( FIG. 1 ) and lifts upwardly against the ledge 39 to pivot the washer lid 20 from the position shown in FIG. 1 to the position shown in FIG. 2 .
The frame-like encapsulation 30 also includes substantially identical corner portions 50 , 50 ( FIGS. 1 and 4 ) defined by the peripheral skirt 31 with a radius (unnumbered) of each corner portion 50 including an elongated curved slot or opening 52 ( FIGS. 4 and 5 ). Two bosses 53 , 54 project inwardly of the peripheral skirt 31 and each includes a respective bore 55 , 56 . Hinge means in the form of a hinge pin 60 is associated with each corner portion 50 and is of a generally L-shaped configuration defined by a pintle portion 61 connected by a radius portion 62 to a mounting portion 63 which includes respective flattened recessed portions 64 , 65 seated upon and receiving therein the bosses 53 , 54 , respectively. Threaded fasteners 64 ′, 65 ′ are fed through bores (unnumbered) of the bosses 53 , 54 and are threaded into threaded openings (unnumbered) of the flattened portions 64 , 65 , respectively, of the mounting portion 63 of each hinge 60 thereby rigidly attaching each of the hinges 60 to the peripheral skirt 31 adjacent an associated one of the rear corner portions 50 . The pintle portions 61 of the hinge pins 60 lie in coaxial relationship to each other and project in opposite directions. Each pintle portion 61 is fitted in one of the openings 15 ( FIG. 4 ) of the inner peripheral wall 14 of the upper frame 13 of the washer body 11 to thereby permit pivoting movement of the washer lid 20 between the positions shown in FIGS. 1 and 2 of the drawings.
At the corner portion 50 adjacent the hand recess 40 ( FIGS. 3 , 7 , 8 and 9 ), a one-piece molded switch-actuator mechanism 69 defined by a mounting block 70 having a switch actuator leg 71 rests upon four substantially parallel relatively spaced reinforcing ribs 72 which project downwardly from the inner surface 34 of the frame-like encapsulation 30 . The peripheral skirt 31 in the area of the ribs 72 includes two bores 74 through which pass fasteners 75 which are threaded into the mounting block 70 to rigidly secure the same in the manner illustrated in FIGS. 7 through 9 of the drawings. The leg 71 of the switch-actuating mechanism 69 is aligned with the safety “ON”/“OFF” switch 18 to close the latter when the washer lid 20 is closed ( FIG. 1 ) and open the latter when the washer lid 20 is open ( FIG. 2 ) to respectively start and stop the washer agitator (not shown) in a conventional manner.
A substantially inwardly directed flange 85 is located at each of the front corners 50 , 50 of the washer lid 20 in spaced relationship to the inner surface 34 ( FIGS. 3 , 7 and 9 ). The flange 85 illustrated at the upper left hand corner 50 of FIG. 3 includes an opening 86 carrying a rubber or similar flexible stop (not shown) which contacts and rests upon the horizontal frame portion 16 of the upper frame 13 of the washer body 11 when the washer lid 20 is in the closed position thereof ( FIG. 1 ). The leg 71 of the switch-actuating mechanism 69 passes through and is radially supported by the opening 86 of the flange 85 ( FIGS. 7 and 9 ).
As is most readily apparent from FIG. 1 of the drawings, the washer lid 20 presents an extremely aesthetic appearance to the overall washer 10 due to the relatively smooth and unbroken upper/outer surface 35 of the encapsulation 30 . Even in the open position ( FIG. 2 ) of the washer lid 20 , the interior of the washer lid 20 is relatively aesthetic in appearance since the hinges 60 , 60 are unobtrusive, as is the design and location of the switch block 69 which is partially hidden by the flange 85 ( FIG. 7 ). However, most important is the fact that, even though the panel 21 is constructed from glass, the specific blend of the polymer and the mica glass beads from which the frame-like encapsulation 30 is injection molded achieves an intimate bond between the components, absent fracture or weakening of the encapsulation 30 due to the similarities between the low shrink ratios and elasticities of these materials. Since the tempered glass panel 21 has almost a zero coefficient of expansion, there will obviously not be any material of the expansion or contraction of the same relative to the injected polymeric/copolymeric material of the encapsulation 30 at temperatures ranging between −30° F. to −140° F., temperatures which heretofore would cause injection molded polypropylene to fracture. Hence, a strong, durable and aesthetic acceptable washer lid 20 is achieved by the present invention, though usage is as other than a washer lid is well within the breadth of the present disclosure.
Although a preferred embodiment of the invention has been specifically illustrated and described herein, it is to be understood that minor variations may be made in the apparatus without departing from the spirit and scope of the invention, as defined by the appended claims. | A washer door or lid as defined by a tempered glass panel bordered by an open frame-like encapsulation of one-piece injection molded polymeric/copolymeric synthetic plastic material. The latter material is preferably acrylonitrile/styrene/acrylate polymer blended with mica glass beads at a ratio of substantially 70%-30% to 90%-10% by weight, but preferably 80%-20% by weight. Further specifics of the washer lid include a relatively thick inner periphery of the encapsulation which securely grips and reinforces an outer peripheral edge of the tempered glass panel, a rigid outer peripheral skirt, an indiscrete handle, a reinforced hand corder for a switch actuator and opposite rear corners carrying hinges for securing the washer lid to an associated washer opening. | 3 |
This application is a continuation-in-part of U.S. patent application Ser. No. 11/383,192, filed May 12, 2006 now abandoned.
FIELD OF THE INVENTION
The present invention relates to manufacture of heat dissipation devices, and more specifically, to manufacture of embedding a heat pipe into a seat.
BACKGROUND OF THE INVENTION
FIG. 1 shows a U-shaped heat pipe pressed. The heat pipe 1 a has an evaporation section 10 a . The bottom of the evaporation section 10 a must be pressed to form a flat heated surface 100 a for directly and planarly touching a heat source. During the pressing process, the stamping die must have a flat plane. When a plane of the stamping die initially meets a curved surface of the heat pipe 1 a , the touch portion will be linear and then become planar. However, the initially linear touch tends to invite a problem of stress concentration. Therefore, a recess 101 a often forms on the heated surface 100 a of the heat pipe 1 a . When once the recess 101 a appears, an additional grinding procedure after pressing will be necessary for effacing the recess 101 a.
This problem can be solved by adopting a multi-stroke progressive pressing procedure. This procedure can progressively press the pipe to be flat, but it must use various stamping dies with different recessing depth or shapes. Meanwhile, only one stamping die can be used to press the pipe at some time. Thus, during the pressing process those stamping dies must be changed one by one in order to ensure the flatness of the pipe being pressed. It is very inconvenient and uneconomical for the manufactures.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a new and improved method, which can embed a heat pipe into a slot of a seat and form a flat plane on the heat pipe at the same time without changing stamping dies.
To accomplish the object abovementioned, one preferred embodiment of the invention includes the steps of:
a) preparing a heat pipe and a heat-conducting seat having a slot;
b) disposing the heat pipe in the slot;
c) arranging the heat pipe with the heat-conducting seat on a power press machine, wherein the power press machine has:
a bolster bed for being placed by the heat pipe with the heat-conducting seat; and
a ram over the bolster bed, having a plurality of stamping dies, each of the stamping dies having a pressing surface, wherein one of the pressing surfaces is a flat plane, and each of the others has a recess sequentially with different depth; and
d) pressing the heat pipe deposed in the slot sequentially with each of the stamping dies.
BRIEF DESCRIPTION OF THE DRAWINGS
The object, features and advantages of the invention will become readily apparent to those skilled in the art upon reading the description of the exemplary embodiment, in conjunction with the attached drawings, in which:
FIG. 1 shows a heat pipe with a plane pressed by conventional method;
FIG. 2 is a flowchart of the method according to the present invention;
FIG. 3 is an exploded view of the heat pipes, heat-conducting seat and holder;
FIGS. 4 and 5 illustrate how the heat pipe passes through the heat-conducting seat and the holder;
FIG. 6 is a partially sectional view showing the heat pipe in the slot;
FIG. 7 illustrates a perspective view of the power press machine;
FIG. 8 shows how the holder is mounted on the working area of the bolster bed;
FIG. 9 shows the holder with the heat pipe and heat-conducting seat, which is mounted on the power press machine;
FIGS. 10A-D sequentially illustrate the progressive status for the heat pipe pressed by different stamping dies; and
FIG. 11 shows a heat pipe pressed by the method of the invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 2 , which shows a flowchart of the invention, the present invention provides a method for embedding a heat pipe into a heat-conducting seat.
Referring to FIGS. 2 and 3 , step S 1 of the method provides at least one heat pipe 1 and a heat-conducting seat 2 for coupling with the heat pipe 1 . FIG. 2 shows an embodiment in which there are 3 heat pipes 1 , but those skilled in the art must know the number of the heat pipes 1 can vary for practical requirements. The bottom 20 of the heat-conducting seat 2 has slots 21 for accommodating an evaporation section 10 of the heat pipes 1 .
Step S 2 of the method disposes the evaporation section 10 of the heat pipes 1 in the slots 21 of the heat-conducting seat 2 . Both the heat pipes 1 and the heat-conducting seat 2 are fixed on a holder 3 . As shown in FIGS. 4 and 5 , the holder 3 may have a through hole 30 for accommodating the condensation section 11 of the heat pipes 1 . Further referring to FIG. 6 , the slot 21 is of a C shape. A part of the heat pipe 1 is higher than the bottom 20 of the heat-conducting seat 2 and protrudes from the slot 21 when the heat pipe 1 is accommodated in the slot 21 . The protrusive portion of the heat pipe 1 is just the portion which will be pressed in later steps. Additionally, as shown in FIG. 3 , the holder 3 may preferably has one or more handles 32 for conveniently being held by a user.
Referring to FIGS. 2 and 7 , step S 3 of the invention arranges the holder 3 on a power press machine 4 . The holder 3 includes a bolster bed 40 and a ram 41 over it. There are a plurality of working areas for positioning the holder 3 on the bolster bed 40 . In a preferred embodiment as shown in FIG. 7 , there are a first working area 400 , a second working area 401 , a third working area 402 and a fourth working area 403 . These working areas 400 - 403 are arranged in a row. Each of the working areas 400 - 403 has two positioning bars 400 a - 403 a responding to grooves 31 on the holder 3 as shown in FIG. 8 , so that the holder 3 can be precisely mounted on each working area 400 - 403 of the bolster bed 40 . Moreover, one or more receiving holes 400 b , 401 b , 402 b and 403 b , which can accommodate excessive portion of the heat pipe 1 , are disposed on each working area 400 - 403 . The holder 3 is not a necessary element. The heat pipe 1 and heat-conducting seat 2 may also be directly mounted on the bolster bed 40 if there is a particular arrangement between them.
The ram 41 of the power press machine 4 is used for downward pressing a material on the bolster bed 40 . There are a plurality of stamping dies 410 - 413 under the ram 41 . In a preferred embodiment as shown in FIG. 9 , the number of the stamping dies 410 - 413 is four, i.e. first, second, third and fourth stamping die. Those stamping dies 410 - 413 are corresponding to the working areas 400 - 403 , respectively.
FIGS. 10A-10D shows the differences among the stamping dies 410 - 413 . Each of the stamping dies 410 - 413 has a pressing surface 410 a - 413 a , wherein the fourth pressing surface 413 a is a flat plane as shown in FIG. 10D , and the first, second and third pressing surfaces 410 - 412 separately have a recess 410 b - 412 b with different depth from deep to flat. Additionally, a plurality of guiding rods 414 downward extend from the ram 41 . The guiding rods 414 are corresponding to guiding holes 404 on the bolster bed 40 for providing necessary pressing depth of the guiding rods 414 .
Step S 4 of the invention sequentially presses the heat pipe 1 with different stamping dies 410 - 413 by means of moving the heat pipe 1 onto different working areas 400 - 403 . In other words, the holder 3 holding both the heat pipe 1 and the heat-conducting seat 2 is moved sequentially from the first working area 400 to the fourth working area 403 after one of the stamping dies 410 - 413 corresponding to heat pipe 1 on the holder 3 has pressed the heat pipe 1 once. For example, the first stamping die 410 presses the heat pipe 1 on the holder 3 mounted on the first working area 400 . Then, the holder 3 is moved to the second working area 401 for being pressed by the second stamping die 411 . Therefore, the heat pipe 1 being pressed by the stamping dies 410 - 413 can be progressively transformed to form a flat plane 100 as shown in FIG. 11 .
While exemplary embodiment of the foregoing invention has been set forth for purposes of illustration, the foregoing description should not be deemed a limitation of the invention herein. Accordingly, various modifications, adaptations, and alternatives may occur to one skilled in the art without departing from the spirit and the scope of the present invention. | A method for embedding a heat pipe into a slot of heat-conducting seat is disclosed. The method has the exposed portion of the heat pipe be flat and coplanar with the surface of the heat-conducting seat after the heat pipe is embedded into the slot of the seat. The method utilizes a power press machine with multiple stamping dies to progressively press the heat pipe. | 8 |
RELATED APPLICATIONS
[0001] This application is a division of U.S. patent application Ser. No. 11/296,053, filed Dec. 5, 2005, which is incorporated herein by reference.
BACKGROUND
[0002] The invention relates to a fluid-heating apparatus, such as an electric water heater, that can determine an operating condition of the apparatus, and a method of detecting a dry-fire condition and preventing operation of the fluid-heating apparatus when a dry-fire condition exists.
[0003] When an electric-resistance heating element fails in an electric water heater, the operation of the heater is diminished until the element is replaced. This can be an inconvenience to the user of the water heater.
SUMMARY
[0004] Failure of the electric-resistance element may not be immediate. For example, the element typically has a sheath isolated from an element wire by an insulator, such as packed magnesium oxide. If the sheath is damaged, the insulator can still insulate the wire and prevent a complete failure of the element. However, the insulator does become hydrated over time and the wire eventually shorts, resulting in failure of the element. The invention, in at least one embodiment, detects the degradation of the heating element due to a damaged sheath prior to failure of the heating element. The warning of the degradation to the element prior to failure of the element allows the user to replace the element with little downtime on his appliance.
[0005] A heating element generates heat that can be transferred to water surrounding the heating element. Water can dissipate much of the heat energy produced by the heating element. The temperature of the heating element rises rapidly initially when power is applied and then the rate of temperature rise slows until the temperature of the heating element remains relatively constant. Should power be applied to the heating element prior to the water heater being filled with water or should a malfunction occur in which the water in the water heater is not at a level high enough to surround the heating element, a potential condition known as “dry-fire” exists. Because there is no water surrounding the heating element to dissipate the heat, the heating element can heat up to a temperature that causes the heating element to fail. Failure can occur in a matter of only seconds. Therefore, it is desirable to detect a dry-fire condition quickly, before damage to the heating element occurs.
[0006] In one embodiment, the invention provides a method of detecting a dry-fire condition of an electric-resistance heating element. The method includes applying a first electric signal to the heating element and detecting a first value of an electrical characteristic during the application of the first electric signal. The first electric signal is then disconnected from the heating element and a second electric signal, substantially different from the first electric signal, is applied to the heating element. The second electric signal is disconnected from the heating element and a third electric signal, substantially different from the second electric signal, is applied to the heating element. A second value of the electrical characteristic is detected during the application of the third electric signal, and a determination is made of the potential for a dry-fire condition based on the first and second values of the electrical characteristic.
[0007] In another embodiment, the invention provides a fluid-heating apparatus for heating a fluid. The fluid-heating apparatus includes a vessel, an inlet to introduce the fluid into the vessel, an outlet to remove the fluid from the vessel, a heating element, and a control circuit. The control circuit is configured to apply a first electric signal to the heating element, read a first value of an electrical characteristic, apply a second electric signal to the heating element, the second electric signal being substantially different than the first electric signal, apply a third electric signal to the heating element, the third electric signal being substantially different than the second electric signal, read a second value of the electrical characteristic, determine whether a potential dry-fire condition exists based on the first and second values, and apply a fourth electric signal to the heating element if the potential dry-fire condition does not exist, the fourth electric signal being substantially different than the first third signal.
[0008] Other aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 is a partial exposed view of a water heater embodying the invention.
[0010] FIG. 2 is a partial exposed, partial side view of an electrode capable of being used in the water heater of FIG. 1 .
[0011] FIG. 3 is a partial block diagram, partial electric schematic of a first control circuit capable of controlling the electrode of FIG. 2 .
[0012] FIG. 4 is a partial block diagram, partial electric schematic of a second control circuit capable of controlling the electrode of FIG. 2 .
[0013] FIG. 5 is a partial block diagram, partial electric schematic of a third control circuit capable of controlling the electrode of FIG. 2 .
[0014] FIG. 6A is a chart of a temperature curve of the electrode of FIG. 2 submerged in water.
[0015] FIG. 6B is a chart of a temperature curve of the electrode of FIG. 2 exposed to air.
[0016] FIG. 7 is partial block diagram, partial electric schematic of a fourth control circuit capable of controlling the electrode of FIG. 2 and detecting a dry-fire condition.
[0017] FIG. 8 is a flowchart of the operation of the control circuit of FIG. 7 for detecting a dry-fire condition.
[0018] FIG. 9A is a chart of a resistance curve of the electrode of FIG. 2 submerged in water.
[0019] FIG. 9B is a chart of a resistance curve of the electrode of FIG. 2 exposed to air.
DETAILED DESCRIPTION
[0020] Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limited. The use of “including,” “comprising” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. The terms “mounted,” “connected,” “supported,” and “coupled” are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings. Further, “connected” and “coupled” are not restricted to physical or mechanical connections or couplings, and can include electrical connections or couplings, whether direct or indirect.
[0021] FIG. 1 illustrates a storage-type water heater 100 including an enclosed water tank 105 (also referred to herein as an enclosed vessel), a shell 110 surrounding the water tank 105 , and foam insulation 115 filling the annular space between the water tank 105 and the shell 110 . A typical storage tank 105 is made of ferrous metal and lined internally with a glass-like porcelain enamel to protect the metal from corrosion. However, the storage tank 105 can be made of other materials, such as plastic. A water inlet line or dip tube 120 and a water outlet line 125 enter the top of the water tank 105 . The water inlet line 120 has an inlet opening 130 for adding cold water to the water tank 105 , and the water outlet line 125 has an outlet opening 135 for withdrawing hot water from the water tank 105 . The tank may also include a grounding element (or contact) that is in contact with the water stored in the tank. Alternatively, the grounding element can be part of another component of the water heater, such as the plug of the heating element (discussed below). The grounding element comprises a metal material that allows a current path to ground.
[0022] The water heater 100 also includes an electric resistance heating element 140 that is attached to the tank 105 and extends into the tank 105 to heat the water. An exemplary heating element 140 capable of being used in the water heater 100 is shown in FIG. 2 . With reference to FIG. 2 , the heating element 140 includes an internal high resistance heating element wire 150 , surrounded by a suitable insulating material 155 (such as packed magnesium oxide), a metal jacket (or sheath) 160 enclosing the insulating material, and an element connector assembly 165 (typically referred to as a plug) that couples the metal jacket 160 to the shell 110 , which may be grounded. For the construction shown, the connector assembly 165 includes a metal spud 170 having threads, which secure the heating element 140 to the shell 110 by mating with the threads of an opening of the shell 110 . The connector assembly 165 also includes connectors 175 and 180 for electrically connecting the wire 150 to the control circuit (discussed below), which provides controlled power to the wire 150 . While a water heater 100 having the element 140 is shown, the invention can be used with other fluid-heating apparatus for heating a conductive fluid, such as an instantaneous water heater or an oil heater, and with other heater element designs and arrangements.
[0023] A partial electrical schematic, partial block diagram for one construction of a control circuit 200 used for controlling the heating element 140 is shown in FIG. 3 . The control circuit 200 includes a microcontroller 205 . As will be discussed in more detail below, the microcontroller 205 receives signals or inputs from a plurality of sensors or circuits, analyzes the inputs, and generates one or more outputs to control the water heater 100 . In one construction, the microcontroller 205 includes a processor and memory. The memory includes one or more modules having instructions. The processor obtains, interprets, and executes the instructions to control the water heater 100 . Although the microcontroller 205 is described as having a processor and memory, the invention may be implemented with other controllers or devices including a variety of integrated circuits (e.g., an application-specific-integrated circuit) and discrete devices, as would be apparent to one of ordinary skill in the art. Additionally, the microcontroller 205 and the control circuit 200 can include other circuitry and perform other functions not discussed herein as is known in the art.
[0024] Referring again to FIG. 3 , the control circuit 200 further includes a current path from a power supply 201 to the heating element 140 back to the power supply 201 . The current path includes a first leg 202 and a second leg 203 . The first leg 202 connects the power source 201 to a first point 206 of the heating element 140 and the second leg 203 connects the power source 201 to a second point 207 of the heating element 140 . A thermostat, which is shown as a switch 210 that opens and closes depending on whether the water needs to be heated, is connected in the first leg 202 between the power source 201 and the heating element 206 . When closed, the thermostat switch 210 allows a current from the power source 201 to the heating element 140 and back to the power source 201 via the first and second legs 202 and 203 . This results in the heating element 140 heating the water to a desired set point determined by the thermostat. The heating of the water to a desired set point is referred to herein as the water heater 100 being in a heating state. When open, the thermostat switch 210 prevents a current flow from the power source 201 to the heating element 140 and back to the power source 201 via the first and second legs 202 and 203 . This results in the water heater 100 being in a non-heating state. Other methods of sensing the water temperature and controlling current to the heating element 140 from the power source 201 are possible (e.g., an electronic control having a sensor, the microcontroller 205 coupled to the sensor to receive a signal having a relation to the sensed temperature, and an electronic switch such as a triac controlled by the microcontroller in response to the sensed temperature).
[0025] As just stated, the thermostat switch 210 allows a current through the heating element 140 when the switch 210 is closed. A variable leakage current can flow from the element wire 150 to the sheath 160 via the insulating material 155 when a voltage is applied to the heating element 140 . The variable resistor 215 represents the leakage resistance, which allows the leakage path. The resistance between the wire and ground drops from approximately 4,000,000 ohms to approximately 40,000 ohms or less when the heating element 140 degrades due to a failure in the sheath 160 . This will be discussed in more detail below.
[0026] The control circuit 210 further includes a voltage measurement circuit 220 and a current measurement circuit 225 . The voltage measurement circuit 220 , which can include a filter and a signal conditioner for filtering and conditioning the sensed voltage to a level suitable for the microcontroller 205 , senses a voltage difference between the first and second legs 202 and 203 . This voltage difference can be used to determine whether the thermostat switch 210 is open or closed. The current measurement circuit 225 senses a current to the heating element 140 with a torroidal current transformer 230 . The torroidal current transformer 235 can be disposed around both legs 202 and 203 to prevent current sense signal overload during the heating state of the water heater 100 , and accurately measure leakage current during the non-heating state of the water heater 100 . The current measurement circuit 225 can further include a filter and signal conditioner for filtering and conditioning the sensed current value to a level suitable for the microcontroller 205 .
[0027] During operation of the water heater 100 , the sheath 160 may degrade resulting in a breach (referred to herein as the aperture) in the sheath 160 . When the aperture exposes the insulating material 155 , the material 155 may absorb water. Eventually, the insulating material 155 may saturate, resulting in the wire 150 becoming grounded. This will result in the failure of the element 140 .
[0028] When the insulating material 155 absorbs water, the material 155 physically changes as it hydrates. The hydrating of the insulating material 155 decreases the resistance 215 of a leakage path from the element wire 150 to the grounded element (e.g., the heating element plug 165 and the coupled sheath 160 ). The control circuit 200 of the invention recognizes the changing of the resistance 215 of the leakage path, and issues an alarm when the leakage current increases to a predetermined level.
[0029] More specific to FIG. 3 , it is common in the United States to apply 240 VAC to the element wire 140 by connecting a first 120 VAC to the first leg 202 and a second 120 VAC to the second leg 203 . The thermostat switch 210 removes the first 120 VAC from being applied to the heating element 140 , thereby having the water heater 100 enter a non-heating state. However, as shown in FIG. 3 , the second 120 VAC through the second leg is still applied to the heating element 140 . As a consequence, a leakage current can still flow through the leakage resistance 215 . The voltage measurement circuit 220 provides a signal to the microcontroller 205 representing, either directly or through analysis by the microcontroller 205 , whether the thermostat switch 210 is in an open state, and the current measurement circuit 230 provides a signal to the microcontroller 205 representing, either directly or through analysis by the microcontroller 205 , the current through the circuit path including the leakage current. The microcontroller 205 can issue an alarm when the measured leakage current is greater than a threshold indicating the heating element 140 has a degrading sheath 160 . The threshold value can be set based on empirical testing for the model of the water heater 100 . The alarm can be in the form of a visual and/or audio alarm 250 . It is even envisioned that the alarm can be in the form of preventing further heating of the water until the heating element 140 is changed.
[0030] In another construction of the water heater 100 , the voltage measurement circuit 220 may not be required if the control of the current to the heating element 140 is performed by the microcontroller 205 . That is, the voltage measurement circuit 220 can inform the microcontroller 205 when the water heater 100 enters a heating state. However, in some water heaters, the microcontroller 205 receives a temperature of the water in the tank 105 from a temperature sensor and controls the current to the heating element 140 via a relay (i.e., directly controls the state of the water heater 100 ). For this construction, the voltage measurement circuit 220 is not required since the microcontroller knows the state of the water heater 100 .
[0031] In yet another construction of the water heater 100 , the microcontroller 205 (or some other component) may control the current measurement circuit 225 to sense the current through the heating element 140 only during the “off” state. This construction allows the current measurement circuit 225 to be more sensitive to the leakage current during the non-heating state.
[0032] Referring to TABLE 1, the table provides the results of eight tests performed on eight different elements. Each of the elements where similar in shape to the element 140 shown in FIG. 2 . The elements were 4500 watt elements secured in 52 gallon electric water heaters similar in design to the water heater 100 shown in FIG. 1 . Various measurements of the elements were taken during the tests. The measurements include the “Power ‘On’ Average Measured Differential Current”, the “Power ‘On’ Maximum Measured Differential Current”, the “Power ‘Off’ Average Measure Differential Current (ma)”, and the “Power ‘Off’ Maximum Measured Differential current.” Aperture were introduced to the sheath 160 of elements E, F, G, and H. The apertures resulted in the degradation of the insulating materials 155 . Measurements for the elements EFGH were taken while the insulators degraded. The data in TABLE 1 shows that the current measurements of elements with intact sheaths 160 taken during the “on” state (or heating state), overlap with the current measurements of elements with a damaged sheath 160 . For example, the element “Edge Hole G”, has a lower average current than the good element C and the good element D. In contrast, the current measurements made during the “off” state (or non-heating state) indicate a wide gap in current readings for an element with a damaged sheath 160 versus the element with an intact sheath 160 . For example, the lowest average current measured for a degraded sheath 160 , Edge Hole G at 12.5 ma, is over six times higher than the highest average current measured for an uncompromised element, i.e., Good D.
TABLE 1 DIFFERENTIAL CURRENT MEASUREMENTS POWER “ON” POWER “ON” POWER “OFF” POWER “OFF” AVERAGE MAXIMUM AVERAGE MAXIMUM MEASURED MEASURED MEASURED MEASURED DIFFERNTIAL DIFFERENTIAL DIFFERNTIAL DIFFERNTIAL ELEMENT CURRENT(ma) CURRENT(ma) CURRENT(ma) CURRENT(ma) Good A 0.45 2.78 0.56 3.15 Good B 3.78 4.19 0.15 1.72 Good C 4.41 5.15 0.10 0.12 Good D 8.38 9.73 2.07 2.90 Center Hole E 59.9 >407 218.8 >407 Center Hole F 79.8 >407 144.3 378 Edge Hole G 4.38 24.5 12.5 78.2 Edge Hole H 9.44 14.7 13.8 15.2
[0033] A partial electrical schematic, partial block diagram for another construction of the control circuit 200 A used for controlling the heating element 140 is shown in FIG. 4 . Similar to the construction shown in FIG. 3 , the control circuit 200 A includes the microcontroller 205 , the thermostat switch 210 A, the voltage measurement circuit 220 , and the current measurement circuit 225 . However, for the construction of the control circuit in FIG. 4 , the first leg 202 A of the circuit 200 A is connected to 120 VAC or 240 VAC and the second leg 203 A of the control circuit 200 is connected to ground. As further shown in FIG. 4 , the double pole thermostat switch 210 A is electrically connected between the current measurement circuit 225 and 120 VAC or 240 VAC. The operation of the control circuit 200 A for FIG. 4 is similar to the control circuit 200 for FIG. 3 . TABLE 2 demonstrates a comparison between a heating element 140 initially having no apertures and the element 140 having an aperture at the edge of the element 140 . As can be seen, TABLE 2 demonstrates a large difference in current between the degraded element and the good element during the non-heating state.
TABLE 2 DIFFERENTIAL CURRENT MEASUREMENTS DURING POWER “OFF” CONDITION (240 VAC) ELEMENT ID Starting Current (mA) Current at 1 Hour (mA) Good 0.04 mA 0.15 mA Carter Hale 560 mA 693 mA
[0034] Before proceeding further, it should be understood that the constructions described thus far can include additional circuitry to allow for intermittent testing. For example and as shown in FIG. 2 , a second switch 255 controlled by the microcontroller 225 can be added to attach the power source 201 A to the heating element 140 when thermostat switch 210 A is open, allowing the microcontroller 225 to perform a leakage current calculation.
[0035] A partial electrical schematic, partial block diagram for yet another construction of the control circuit 200 B used for controlling the heating element 140 is shown in FIG. 5 . Similar to the construction shown in FIG. 3 , the control circuit 200 B includes the microcontroller 205 , a thermostat switch 210 B, the voltage measurement circuit 220 , and a current measurement circuit 225 B. However, for the construction of the control circuit 200 B in FIG. 5 , the arrangement and operation of the circuit 200 B shown in FIG. 5 is slightly different than the arrangement of the circuit 200 shown in FIG. 3 . As shown in FIG. 5 , the current measurement circuit 225 B includes a current resistive shunt 500 that is electrically connected between a 12 VDC (or 12 VAC) power supply 505 and the thermostat switch 210 B. The thermostat switch 210 B is controlled by the thermostat temperature sensor and switches between the 120 VAC (or 240 VAC) power source and the 12 VDC (or 12 VAC) power supply 505 . The voltage measurement circuit 220 is electrically connected in parallel with the heating element to determine the state of the water heater 100 . The operation of the control circuit 200 B for FIG. 5 is somewhat similar to the control circuit 200 for FIG. 3 . However, unlike the control circuit 200 for FIG. 3 , when the control circuit 200 B moves to the non-heating state, the thermostat switch 210 B applies the voltage of the low-voltage power supply 505 to the heating element 140 . TABLE 3 demonstrates a comparison between a heating element 140 initially having no apertures and the element 140 having an aperture at the edge of the element 140 . As can be seen, TABLE 3 demonstrates a large difference in current between the degraded element and the good element during the non-heating state.
TABLE 3 DIFFERENTIAL CURRENT MEASUREMENTS DURING POWER “OFF” CONDITION (12 VDC) ELEMENT ID Starting Current (mA) Current at 1 Hour (mA) Good 0.0 mA 0.0 mA Center Hole 18 mA 18 mA
[0036] When the temperature in the water heater 100 drops below a predetermined threshold the water heater 100 attempts to heat the water to a temperature greater than the predetermined threshold plus a dead band temperature by applying power to the heating element 140 . The heating element 140 generates heat that can be transferred to water surrounding the heating element 140 . Much of the heat energy produced by the heating element 140 can be dissipated by the water. FIG. 6A illustrates the temperature of a heating element 140 following application of power to the heating element 140 and wherein the heating element 140 is surrounded by water. The temperature of the heating element 140 rises rapidly initially and then the temperature rise slows until the temperature of the heating element 140 remains relatively constant. The constant temperature maintained by the heating unit 140 can be below a temperature wherein the heating element 140 fails.
[0037] Should power be applied to the water heater 100 prior to the water heater 100 being filled with water or should a malfunction occur in which the water in the water heater 100 is not at a level high enough to surround the heating element 140 , applying power to the heating element 140 creates a condition known as “dry-fire.” As shown in FIG. 6B , during a dry-fire condition the heating element 140 heats up and, because there is no water surrounding the heating element 140 to dissipate the heat, continues to heat up to a temperature that causes the heating element 140 to fail. Failure of the heating element 140 during a dry-fire condition can occur in only a matter of seconds. It is, therefore, desirable to detect a dry-fire condition quickly, before damage occurs to the heating element 140 .
[0038] FIG. 7 illustrates a partial block diagram, partial schematic diagram of a construction of a fourth control circuit 600 that detects a dry-fire condition and prevents power from being applied to the heating element 140 when a dry-fire condition exists.
[0039] In some constructions, the control circuit 600 includes a relatively high-voltage power source (e.g., 120 VAC, 240 VAC, etc.) 201 B, a heating element 140 , a relatively low voltage power source (e.g., +12 VDC, 12 VAC, +24 VDC, etc.) 605 , a current sensing circuit 610 , a controller 205 , a temperature sensing circuit 615 , an alarm 620 , a normally open switch 625 , and a double-pole, double-throw relay 630
[0040] As shown in the construction of FIG. 7 , the normally closed (“NC”) contacts of the relay 630 are coupled to the high-voltage power source 201 B through switch 625 . The normally open (“NO”) contracts of the relay 630 are coupled to the low-voltage power supply 605 . The output contacts of the relay 630 are coupled to the heating element 140 . When the switch 625 is closed and power is not applied to the coil (indicated at 635 ) of the relay 630 , the relay 630 remains in a state wherein the normally closed contacts remain closed and high voltage is applied to the heating element 140 enabling the heating element 140 to generate heat. When power is applied to the coil 635 of the relay 630 , the relay 630 closes the NO contacts and +12 VDC is applied to the heating element 140 . The voltage of the low-voltage power supply 605 can be selected such that the heating element 140 would not be harmed from prolonged exposure in a dry-fire condition.
[0041] In this construction, the controller 205 is coupled to the temperature sensor 615 and the current sensor 610 , and receives indications of the temperature in the water heater 100 and the current drawn from the low-voltage power supply 605 from each sensor respectively. The controller 205 is also coupled to the alarm 620 , the switch 625 , and the relay 630 .
[0042] FIG. 8 represents a flow chart of an embodiment of the operation of the control circuit 600 for detecting a dry-fire condition. When the water heater 100 is powered on (block 700 ), the controller 205 applies power (block 705 ) to the coil 635 of the relay 630 . This opens the NC contacts of the relay 630 and closes the NO contacts of the relay 630 . Closing the NO contacts of the relay 630 couples the low-voltage power supply 605 to the heating element 140 .
[0043] In some constructions, the controller reads (block 710 ), from the current sensor 610 , a first current being supplied by the low-voltage power supply 605 to the heating element 140 . Other constructions of the dry-fire detection system 600 can read other electrical characteristics (e.g., voltage via a voltage sensor) of the circuit created by the low-voltage power supply 605 and the heating element 140 .
[0044] Next, the controller 205 closes (block 715 ) the switch 625 and couples the high-voltage power supply 201 B to the NC contacts of the relay 630 . The controller 205 also removes (block 720 ) power from the coil 635 of the relay 630 . This opens the NO contracts of the relay 630 which decouples the low-voltage power supply 605 from the heating element 140 and closes the NC contacts of the relay 630 coupling the high-voltage power supply 201 B to the heating element 140 . Coupling the high-voltage power supply 201 B to the heating element 140 causes the heating element 140 to heat up. The controller 205 delays (block 725 ) for a first time period (e.g., three seconds).
[0045] Following the delay (block 725 ), the controller 205 applies (block 730 ) power to the coil 635 of the relay which opens the NC contacts of the relay 635 and decouples the high-voltage power supply 201 B from the heating element 140 . The first time period can be a length of time that allows the heating element 140 to heat up but can be short enough to ensure the heating element 140 does not achieve a temperature at which it can fail if a dry-fire condition were to exist. Applying power to the coil 635 of the relay 630 also enables the NO contacts of the relay 630 to close and couples the low-voltage power supply 605 to the heating element 140 .
[0046] The controller 205 delays (block 735 ) for a second time period (e.g., ten seconds). During the delay, the heating element 140 begins to cool. The rate at which the heating element 140 cools can be faster if the heating element 140 is surrounded by water. The controller 205 reads (block 740 ), from the current sensor 610 , a second current being supplied by the low-voltage power supply 605 to the heating element 140 . The controller 205 compares (block 745 ) the first sensed current to the second sensed current and determines if the second sensed current is greater than the first sensed current by more than a threshold. If the second sensed current is not greater than the first sensed current by more than the threshold, the controller 205 determines that a dry-fire condition does not exist and continues (block 750 ) normal operation.
[0047] If the second sensed current is greater than the first sensed current by more than the threshold, the controller 205 determines that a dry-fire condition exists and opens (block 755 ) the switch 625 . Opening the switch 625 ensures that the high-voltage power supply 201 B is decoupled from the heating element 140 and prevents the heating element from being damaged. The controller 205 then signals (block 760 ) an alarm to inform an operator of the dry-fire condition.
[0048] FIGS. 9A and 9B illustrate the resistance of the heating element 140 at different points during the dry-fire detection process for a wet-fire condition ( FIG. 9A ) and a dry-fire condition ( FIG. 9B ). At block 720 , the high-voltage power is applied to the heating element 140 . The temperature of the heating element 140 rises which increases the resistance of the heating element 140 . After a delay (block 725 ) the high-voltage power is disconnected from the heating element 140 (block 730 ). In a wet-fire condition, FIG. 9A , the heating element 140 cools relatively rapidly causing the resistance of the heating element 140 to drop relatively rapidly to near the level of resistance of the heating element 140 prior to originally applying the high voltage as shown at block 740 .
[0049] Referring to FIG. 9B , the resistance of the heating element 140 in a dry-fire condition is similar to the resistance of the heating element 140 in a wet-fire condition ( FIG. 9A ) for blocks 720 to 730 . Following disconnection of the high-voltage power at block 730 the heating element 140 , in a dry-fire condition, retains more heat and has a higher resistance for a relatively longer period of time. Testing an electrical characteristic of a circuit including the heating element 140 as explained at block 740 results in, when a dry-fire condition exists, a relatively large differential between the first reading at block 710 and the second reading at block 740 .
[0050] The control circuit 600 can execute the dry-fire detection process once, when power is first applied to the water heater 100 , each time the temperature sensing circuit 615 indicates that heat is needed, or at some other interval. Other constructions of the control circuit 600 can execute the dry-fire detection process at other times where it is determined that the potential for a dry-fire condition exists (e.g., following a period of time wherein the heating element 140 has been coupled to the high power signal).
[0051] Thus, the invention provides, among other things, a new and useful water heater and method of controlling a water heater. Various features and advantages of the invention are set forth in the following claims. | A fluid-heating apparatus for heating a fluid and method of operating the same. The fluid-heating apparatus includes a heating element for heating a fluid surrounding the heating element and a control circuit connected to the heating element and connectable to a power source. The control circuit is configured to determine whether a potential dry-fire condition exists for the heating element. In one implementation, the method includes applying a first electric signal to the heating element, detecting a first value of an electrical characteristic during the application of the first electric signal, applying a second electric signal to the heating element, applying a third electric signal to the heating element, detecting a second value of the electrical characteristic during the application of the third electric signal; and determining whether a potential dry-fire condition exists based on the first and second values. | 5 |
BACKGROUND OF THE INVENTION
[0001] The present invention is directed generally to a valve device for a control cylinder, which is preferably of the type used for electronically controlled pneumatic actuation of the clutch of a motor vehicle.
[0002] In conventional single-acting pneumatic control cylinders in which the pneumatic piston is shifted into its initial position (zero position of the piston rod fixed to the piston) via a return spring, a specified actuation position is established by virtue of the pneumatic pressure prevailing in the piston chamber of the control cylinder. This means that the piston rod of the control cylinder is extended by a specified travel distance compared with its zero position. The air pressure in the control cylinder piston chamber determines the position of the control cylinder piston rod; the air pressure is lowered for retraction of the piston rod toward its zero position and raised for extension toward its maximum position allowed by the cylinder length.
[0003] The air pressure in the control cylinder piston chamber is varied by means of valves. In the simplest case, a switching pressurizing valve raises the air pressure and a switching venting valve lowers the air pressure.
[0004] For application of the control cylinder as an electronically controlled, pneumatically actuated clutch control cylinder as mentioned above, the pressurizing and venting valves are designed as electrically switched valves; the air pressure in the control cylinder piston chamber being varied as desired by the switching of these valves. For precision adjustment of a specified pressure or for establishing a specified pressure gradient, such as in the clutch-engagement process, the valves are actuated in a pulsed mode.
[0005] The control cylinder is connected to the motor vehicle clutch (which can be a push-type or pull-type clutch) in such a way that the motor vehicle clutch is completely disengaged in the piston rod zero position corresponding to a piston chamber pressure of zero. During an increase in the piston chamber pressure, the piston rod becomes extended, engagement begins at a specified piston rod position (clutch engagement point) and, beginning with a further specified position, the clutch is then completely engaged.
[0006] In the zero position of the control cylinder piston rod, in which, as explained, the piston chamber of the cylinder is depressurized and, also, the two valves are in unactuated position, it is possible that small leaks in the pressurizing valve in communication with the supply pressure can cause a gradual pressure buildup in the control cylinder piston chamber. This pressure buildup could be accompanied by undesired extension of the control cylinder piston rod from zero position, which could potentially lead to undesired engagement of the motor vehicle clutch, with the result that the vehicle might experience undesired movement under certain circumstances.
[0007] Undesired pressure buildup can be prevented by occasional actuation of the venting valve. For this purpose, however, the control electronics would require additional programming which may not be consistent with the program that controls the desired switching processes of the valve. Furthermore, additional functions may be required, for example, pressure sensing, that may not be needed for other purposes. Moreover, the system would then have to be continuously energized (current consumption, battery discharge). Such a solution is therefore not particularly advantageous.
SUMMARY OF THE INVENTION
[0008] Generally speaking, in accordance with the present invention, a valve device is provided which avoids the foregoing disadvantages associated with prior art devices and arrangements.
[0009] A valve device for pressurizing or venting the piston chamber of a control cylinder (such as is used, for example, to actuate the clutch of a motor vehicle) according to a preferred embodiment of the present invention includes at least one solenoid-actuated multi-way pressurizing valve and at least one solenoid-actuated multi-way venting valve. Preferably, the pressurizing and venting valves include at least 2/2 ways. The pressurizing valve has a port in communication with a supply pressure and another port in communication with the control cylinder piston chamber; the venting valve has a port in communication with a vent and another port in communication with the control cylinder piston chamber. Both the pressurizing valve and the venting valve are in closed position when deenergized.
[0010] The valve device further includes at least one non-return valve. The non-return valve has a pneumatic inlet in communication with the control cylinder piston chamber. The non-return valve is constructed and arranged to assume an unactuated position when the pneumatic inlet is depressurized, and an actuated position when the pneumatic inlet is pressurized. In unactuated position, the non-return valve has a defined pressure leak. The pressure leak is established as a nominal width which corresponds to a preselected proportion of the nominal width of the pressurizing valve.
[0011] The non-return valve according to the present invention can be disposed separate from or in the control cylinder. If in the control cylinder, the non-return valve can be disposed in the piston or, alternatively, in the housing (including in the end wall thereof). The non-return valve can also be disposed in the pressurizing or venting valves.
[0012] Accordingly, it is an object of the present invention to provide a valve device which is constructed and arranged such that slight leaks in the pressurizing valve do not lead to undesired extension of the control cylinder piston rod, and which does not require additional programming to accomplish such purpose.
[0013] It is also an object of the present invention to provide a valve device which can be readily integrated as a component in devices that are present in any case, whereby additional assembly and connecting-line costs can be avoided.
[0014] Still other objects and advantages of the present invention will in part be obvious and will in part be apparent from the specification.
[0015] The present invention accordingly comprises the features of construction, combination of elements, and arrangement of parts which will be exemplified in the constructions hereinafter set forth, and the scope of the invention will be indicated in the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] For a fuller understanding of the invention, reference is had to the following description taken in connection with the accompanying drawings in which:
[0017] [0017]FIG. 1 a is schematic diagram depicting the pneumatic valve connections for admission of compressed air to a spring-loaded control cylinder containing a valve device according to a preferred embodiment of the present invention;
[0018] [0018]FIG. 1 b is an enlarged view of the inventive valve device depicted in FIG. 1 a;
[0019] [0019]FIG. 1 c is a cross-sectional view of the inventive valve device taken along lines 1 c - 1 c in FIG. 1 b;
[0020] [0020]FIG. 2 is a sectional view depicting the valve device according to a preferred embodiment of the present invention disposed in the piston of a spring-loaded control cylinder;
[0021] [0021]FIG. 3 is a sectional view depicting the valve device according to a preferred embodiment of the present invention alternatively disposed in the housing of a spring-loaded control cylinder;
[0022] [0022]FIG. 4 is a sectional view depicting the valve device according to a preferred embodiment of the present invention alternatively disposed in the venting valve of a spring-loaded control cylinder; and
[0023] [0023]FIG. 5 is an enlarged sectional view depicting a valve device in accordance with an alternative embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0024] Referring to the drawing figures where like reference numerals are used for corresponding parts, FIG. 1 shows a pressurizing (solenoid) valve 1 having a first port 2 in communication with a supply pressure 10 and a second port 3 in communication with a piston chamber 9 of a spring-loaded control cylinder 8 . A venting (solenoid) valve 4 is also provided having a first port 5 in communication with a vent 11 and a second port 6 also in communication with control cylinder piston chamber 9 .
[0025] Solenoid valves 1 and 4 are preferably provided with 2/2 ways, which represent the smallest possible number of ways for such directional multi-way control valves. It should be understood, however, that more than 2/2 ways can also be provided for these valves.
[0026] Solenoid-actuated valves 1 and 4 can be switched via an electronic control device (not shown in the drawings). In order to adjust pressure exactly in control cylinder piston chamber 9 , for example, during the process of clutch engagement in the application of control cylinder 8 as a clutch control cylinder, the valves can be switched in pulsed mode.
[0027] For such an application, it may also be advantageous to provide a further pressurizing valve and a further venting valve, each with larger nominal widths, for example, for the purpose of both rapid pressurizing and rapid venting. Except for the changed nominal width, such valves can have similar designs to those of valves 1 and 4 and can be connected in parallel therewith. In such a paired arrangement, therefore, faster or slower pressure buildup or pressure reduction can be achieved as desired by appropriate valve actuation.
[0028] In the event of a leak in pressurizing valve 1 (in this regard, an explanation of how a sealing seat 28 of venting valve 4 —having the same design as that of pressurizing valve 1 —can be achieved via a magnet armature sealing element 30 is set forth hereinafter in connection with FIG. 4), air passes from supply 10 to control cylinder piston chamber 9 . Even though the air flow is relatively small, pressure that can lead to shifting of control cylinder 8 will eventually build up in piston chamber 9 .
[0029] To prevent such a pressure buildup, pneumatic communication can be provided between the control cylinder piston chamber and an inlet 12 of a non-return valve 7 constructed and arranged in accordance with the present invention.
[0030] Non-return valve 7 preferably has two switched positions. A first, unactuated position is occupied when pneumatic inlet 12 is depressurized. In this situation, as shown in FIG. 1 b , a sealing ball 13 is pressed by the force of a spring 19 against a first sealing seat 17 at pneumatic inlet 12 . In this position, non-return valve 7 is designed to allow a defined leak.
[0031] Preferably, non-return valve 7 is provided with a groove comprising a radial portion 36 and a longitudinal portion 16 (shown in cross section in FIG. 1 c taken along line 1 c - 1 c in FIG. 1 b through the center of sealing ball 13 ) by which a small air opening to vent 11 is formed. Sealing ball 13 is housed in a cylindrical guide 14 , and groove 16 in the cylindrical guide therefore extends as far as a bore 15 at pneumatic inlet 12 .
[0032] A second or actuated position of non-return valve 7 is established when pneumatic inlet 12 is pressurized. Because pressure is present at pneumatic inlet 12 , and also because the leak is relatively small, a backpressure sufficient to press sealing ball 13 sealingly against a second sealing seat 18 can build up, and so inlet 12 is pneumatically shut off from vent 11 .
[0033] The defined leak of non-return valve 7 in its first, unactuated position is determined by the cross section of groove 36 , 16 (FIG. 1 c ). A leak nominal width, such as, for example, 0.3 mm can be established.
[0034] In designing the individual valves, the leak nominal width is preferably matched to the nominal widths of the other valves, especially that of the pressurizing valve. Preferably, the leak nominal width is small compared to the nominal width of the pressurizing valve (in the case of two pressurizing valves, the nominal width of the pressurizing valve having larger cross section is the determining factor for the leak, since a larger sealing seat also exhibits larger leaks). When the pressurizing valve is opened, a backpressure that presses sealing ball 13 against the force of spring 19 onto second sealing seat 18 , thus closing it, builds up promptly at inlet 12 of non-return valve 7 .
[0035] For comparison with inventive non-return valve 7 , the construction of a conventional non-return valve is now described. A conventional non-return valve is used to shut off the air stream in one flow direction and to allow it to pass in the other flow direction. In a conventional ball type non-return valve, the sealing ball is pressed via a spring against a sealing seat at the inlet. In the case of air flow directed from the inlet outward, this sealing seat is opened because air flowing in this direction lifts the sealing ball from the valve seat. On the other hand, the sealing seat remains closed in the case of air flow directed toward the inlet.
[0036] In comparison with the conventional non-return valve, the non-return valve 7 according to the present invention exhibits a very different functional principle. At very low backpressures at inlet 12 , the valve is opened with very small nominal width, to allow a small air stream to pass through. Even at a “normal” small backpressure, however, second sealing seat 18 is promptly occupied, and so the valve is closed. Spring 19 is therefore preferably designed with a relatively compliant spring rate, in such a way that the second sealing seat position is already occupied at a sufficiently low backpressure desired for this purpose, such as, for example, 0.2 bar. On the other hand, it should be appreciated that the ability of a non-return valve of conventional construction to shut off an air stream directed toward the inlet has no bearing for inventive non-return valve 7 .
[0037] It should be understood that, besides application in a spring-loaded control cylinder designed as an actuating cylinder for a motor vehicle clutch, the valve arrangement depicted in FIG. 1 is suitable for all applications in which a gradual pressure buildup in the piston chamber of the spring-loaded control cylinder as a result of valve leaks can lead to undesired actuation of the control cylinder.
[0038] Considering the connections illustrated in FIG. 1, since inlet 12 of non-return valve 7 is in pneumatic communication with a compressed air port 21 of control cylinder piston chamber 9 , with second port 3 of pressurizing valve 1 and with second port 6 of venting valve 4 , it should be understood that non-return valve 7 can also be installed at a position other than that shown in FIG. 1 a , in which case it would not be designed as a separate valve unit, as is the case in FIG. 1 a . For example, non-return valve 7 can also be disposed in spring-loaded control cylinder 8 , which is advantageous because separate installation of a non-return valve is obviated and also because separate connecting lines are not required.
[0039] Referring to FIG. 2, non-return valve 7 is shown installed inside a piston 23 of spring-loaded control cylinder 8 . A piston rod 24 is also depicted. The cylinder return spring is not shown; it is disposed in the inside chamber of piston 23 .
[0040] It is possible to dispense with a return spring in control cylinder 8 , namely in applications in which a return spring is installed in the very device that is actuated by control cylinder 8 (for example, this is the case in certain embodiments of vehicle clutches described above). Moreover, in contrast to the embodiment of a single-acting control cylinder 8 , a control cylinder can also be provided as a double-acting control cylinder, in which a further piston chamber for retraction of piston rod 24 is provided in addition to piston chamber 9 for extension of piston rod 24 . Valves for raising and lowering the pressure are also provided for this further piston chamber.
[0041] Referring now to FIG. 3, as an alternative to the arrangement depicted in FIG. 2, non-return valve 7 can also be installed in a housing 22 of spring-loaded control cylinder 8 , specifically, in the end wall thereof.
[0042] Non-return valve 7 can also be disposed in at least one of the two solenoid-actuated multi-way valves 1 or 4 ; this is depicted in FIG. 4 for the example of venting valve 4 . Indeed, instead of one non-return valve 7 , two non-return valves can be mounted in an arrangement of connections as depicted in FIG. 1.
[0043] Referring now to FIG. 4, venting valve 4 preferably includes a first housing part 26 and a second housing part 27 joined to the first housing part. An armature guide tube 32 together with a magnet coil 31 is preferably disposed in first housing part 26 , and an O-ring seal 33 ensures that second port 6 of the venting valve, in pneumatic communication with control cylinder port 21 , is also sealed relative to armature guide tube 32 and, thus, relative to first housing part 26 .
[0044] A magnet armature 29 is preferably mounted displaceably inside armature guide tube 32 . While magnet coil 31 is not energized, the armature is pushed toward second housing part 27 by a spring (not shown) disposed in a valve pressure volume 35 , as explained in greater detail hereinafter, in such a way that a magnet armature sealing element 30 bears compliantly on a sealing seat 28 of the second housing part, thus closing the sealing seat when the magnet is not actuated (in pressurizing valve 1 of similar design, a slight leakage in the air stream to control cylinder piston chamber 9 can develop due to leaks from supply 10 via the sealing seat).
[0045] When magnet coil 31 is energized, magnet armature 29 is lifted toward a stationary core 37 , magnet armature sealing element 30 lifts up from sealing seat 28 , and pneumatic communication is established between first port 5 of venting valve 4 in communication with vent 11 and control cylinder piston chamber 9 , thus permitting venting of the piston chamber. Preferably, non-return valve 7 is disposed in stationary core 37 such that valve pressure volume 35 is formed between the valve and magnet armature 29 .
[0046] Valve pressure volume 35 is in communication with second port 6 of venting valve 4 via a pressure channel 34 in magnet armature 29 . Valve pressure volume 35 is therefore always in pneumatic communication with control cylinder piston chamber 9 , regardless of the switched position of venting valve 4 . Venting of valve pressure volume 35 is therefore synonymous with venting of control cylinder piston chamber 9 itself.
[0047] As indicated above, the design of pressurizing valve 1 is desirably similar to that of venting valve 4 , with the difference that first port 2 is in communication not with vent 11 but with supply pressure 10 . Just as for venting valve 4 , however, second port 3 is in communication with control cylinder piston chamber 9 , and so non-return valve 7 for venting control cylinder piston chamber 9 can also be disposed above valve pressure volume 35 of pressurizing valve 1 .
[0048] In the embodiment of non-return valve 7 according to FIGS. 1 b and 1 c , sealing ball 13 at first sealing seat 17 forms a circumferential sealing edge which forms an airtight sealing edge. As explained above, the defined leak is achieved by the cross section of radial portion 36 of the groove in the circumferential sealing edge.
[0049] As shown in FIG. 5, the defined leak can also be established by a leak built into the structure of a circumferential sealing edge 38 of first valve seat 17 . Notches 41 are provided in the valve housing around the circumference at first valve seat 17 in order to establish the defined leak (for example, eight notches 41 are provided in the preferred embodiment depicted).
[0050] Non-return valve 7 according to FIG. 5 also exhibits further differences in configuration compared with non-return valve 7 according to FIGS. 1 b and 1 c . For example, instead of a ball there is provided a rotationally symmetric sealing member 39 , which is mounted in cylindrical guide 14 with a certain play (exaggerated in FIG. 5), which ensures the leakage function of longitudinal portion 16 of the groove depicted in FIGS. 1 b and 1 c.
[0051] Furthermore, second sealing seat 18 is desirably formed not as a seat sealing by metal-to-metal contact but as an elastomeric sealing seat. For this purpose, an elastomeric sealing cone 40 can be provided on sealing member 39 . This embodiment is particularly advantageous because of its airtight and “compliant” sealing effect. It should be understood that the sealing member can also have a different shape, such as a rotationally symmetric shape (e.g., like a torpedo or an egg).
[0052] Accordingly, a valve device is provided which is constructed and arranged to prevent undesired extension of the control cylinder piston rod caused by slight leaks in the pressurizing valve, and which does not require additional programming to accomplish this function. The valve device according to the present invention can be readily integrated as a component in devices that are present in any case, such that additional assembly and connecting-line costs can be avoided.
[0053] It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained, and since certain changes may be made in the above constructions without departing from the spirit and scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.
[0054] It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween. | For a valve arrangement of a pneumatically actuated, spring-loaded control cylinder, a non-return valve in pneumatic communication with the control cylinder piston chamber. At very low backpressures in the control cylinder piston chamber caused by leaks of the valve responsible for pressurization of the piston chamber, the chamber is vented by passage of a very small air stream via the non-return valve. In this way, leaks cannot cause a very slow pressure buildup in the control cylinder piston chamber, followed at some time by undesired shifting of the control cylinder. In contrast, in the case of normal pressure buildup, i.e., during switching of the pressurizing valve, the non-return valve is promptly closed and the pressure in the control cylinder piston chamber is not influenced. | 5 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to an image display device and, more particularly, to an image display device wherein image lights are subjected to an image modulation of different colors by a plurality of spatial light modulation elements, the modulated image lights are synthesized by a color synthesizer, and the synthesized image light is displayed while selectively shifting an optical path thereof by a pixel shift device.
[0003] 2. Description of Related Art
[0004] As a conventional image display device, there is known a 3LCD-type image display device wherein a light from a white light source is separated into a red (R) light, a green (G) light and a blue (B) light, and the separated lights are projected to respective liquid crystal display elements as spatial light modulation elements and thereby subjected to image modulation. The modulated R, G and B lights are synthesized by a color synthesizer in the form of a dichroic prism, for example, and then displayed on a screen through a projection lens.
[0005] In such a 3LCD-type image display device, the synthesized image light may be subjected to a wavelength shift due to incidence angle characteristics of a dichroic film of the dichroic prism, thereby causing color irregularities. This sort of color irregularities may occur particularly when an integrator optical system is arranged in an illumination optical system, in order to equalize the illumination distribution of an illumination light emitted from the white light source. This is because the image lights modulated by the respective liquid crystal display elements are projected to the dichroic film at different incidence angles.
[0006] For eliminating such a problem, there is known a method that takes into account the polarization characteristics of the dichroic film, such that the G image light is projected to, and transmitted through the dichroic film in P-polarization, whereas the R and B image lights are projected to, and reflected on the dichroic film in S-polarization, before the R, G and B image lights are synthesized.
[0007] Also, various image display devices have been proposed, wherein the optical paths of the image lights subjected to image modulation by spatial light modulation elements are selectively shifted by pixel shift device, so as to achieve a high resolution. Reference may be had, for example, to Patent Document 1 identified below.
[0008] The pixel shift device includes, as shown in FIG. 9 by way of example, a polarization conversion element 110 and a double refraction plate 111 , such as a liquid crystal panel and a quartz plate, for example. The polarization conversion element 110 selectively rotates the direction of the linear polarization of the modulated image light by 90 degrees while being synchronized with the image modulation by the spatial light modulation elements (not shown), so that the double refraction plate 111 shifts the optical path of the image light according to the direction of the linear polarization, for example, by half a pixel pitch with respect to a horizontal pixel arrangement of the spatial light modulation elements. There are also known a pixel shift device in which a plurality of sets of a polarization conversion element 110 and a double refraction plate 111 are provided so that the position of a displaying pixel can be selectively shifted in different directions, for example, in the horizontal direction, in the vertical direction, or in the oblique direction.
[0009] There is also known an image display device in the form of combination of the above mentioned 3LCD image display device and the pixel shift device shown in FIG. 9 , in which the optical path of the image light synthesized by the dichroic prism is selectively shifted by the pixel shift device so as to achieve a high resolution.
[0010] FIG. 10 shows the configuration of the relevant parts of such an image display device, including a liquid crystal display element 120 R for performing an image modulation for the R light, a liquid crystal display element 120 G for performing an image modulation for the G light, a liquid crystal display element 120 B for performing an image modulation for the B light, a dichroic prism 121 for synthesizing the image lights modulated by the liquid crystal display elements 120 R, 120 G and 120 B, a pixel shift device 122 for selectively shifting the optical paths of the synthesized image lights, and a projection lens 123 for projecting the image lights from the pixel shift device 122 onto a screen (not shown). FIG. 10 further shows an example of the pixel shift device 122 , which includes a set of a polarization conversion element 110 and a double refraction plate 111 , for performing a double-point pixel shift.
[0011] In the image display device shown in FIG. 10 , however, in an attempt to prevent color irregularities caused by incidence angle characteristics of the dichroic film of the dichroic prism 121 , if the G image light from the liquid crystal display element 120 G is projected to, and transmitted through the dichroic film in P-polarization, while the R image light and the B image light from the liquid crystal display element 120 R and the liquid crystal display element 120 B, respectively, are projected to, and reflected by the dichroic film in S-polarization, and those R, G and B image lights are synthesized so that the optical path of the synthesized image lights is selectively shifted by the pixel shift device, the display position of the G image light will be misaligned from the display positions of the R and B lights, because the directions of the linear polarizations of the R, G and B image lights projected to the pixel shift device 122 are not aligned with each other.
[0012] More specifically, in the image display device shown in FIG. 10 , the G image light is projected to the polarization conversion element 110 of the pixel shift device 122 in P-polarization, whereas the R and B image lights are projected to the polarization conversion element 110 in S-polarization. Accordingly, if the R, G and B image lights are projected to the double refraction plate 111 without changing the directions of the linear polarizations of the incident lights by the polarization conversion element 110 , the optical paths of the R and B image lights are not subjected to pixel shift, and only the optical path of the G image light is subjected to a pixel shift, as shown in FIG. 11( a ). Conversely, if the directions of the linear polarizations of the incident lights are rotated by 90 degrees by the polarization conversion element 110 , the G image light is projected to the double refraction plate 111 in S-polarization, whereas the R and B image lights are projected to the polarization conversion element 110 in P-polarization. Accordingly, the optical paths of the R and B image lights are subjected to a pixel shift, and only the optical path of the G image light is not subjected to pixel shift, as shown in FIG. 11( b ). Therefore, the display position of the G image is misaligned from the display positions of the R and B images, which is an obstacle to achievement of high resolution and which may degrade the image quality.
[0013] In order to solve these problems, there has been proposed an image display device wherein a color-selective polarization plane rotation means including a laminated phase plate is arranged between the dichroic prism and the pixel shift device. With such an image display device, the polarization plane of the G light in P-polarization, for example, is rotated and converted into S-polarization, while the polarization planes of the R and B lights are not rotated so as to remain in S-polarization, so that the polarization directions of the image lights of different colors projected to the pixel shift device are aligned with S-polarization. Reference may be had, for example, to Patent Document 2 identified below.
[0014] Patent Document 1: JP 2813041B2
[0015] Patent Document 2: JP 2003-207747A
[0016] In the case of pixel shift device such as that disclosed in JP 2813041B2 mentioned above, it is common to make the pixel shift device into a unit in order to assemble it while managing the specific characteristics inherent to the pixel shift device.
[0017] Therefore, in the case of an arrangement wherein a color-selective polarization plane rotation means in the form of a laminated phase plate is simply arranged between the dichroic prism and the pixel shift device, as in the image display device disclosed in JP 2003-207747A, the pixel shift device and the laminated phase plate would be installed separately for assembling the image display device.
[0018] Furthermore, since the laminated phase plate is exposed to outside, it is necessary to carry out an advance step of applying an antireflection coating to a purchased laminated phase plate or cleaning the surface of the laminated phase plate for removing dust thereon, resulting in burdensome assembling operation and increased cost.
[0019] In addition, the pixel shift may cause a color mixture if, in terms of the polarization conversion characteristics of the laminated phase plate, there are overlaps of a P-polarization component and an S-polarization component in the transitional regions of the polarization conversion at upper or lower edge of the P-S conversion or, in other words, in the transitional region from the longer wavelength band of the B light to the shorter wavelength band of the G light, and the transitional region from the longer wavelength band of the G light to the shorter wavelength band of the R light, as shown in FIG. 12 .
[0020] More specifically, if there are overlaps of the P-polarization component and the S-polarization component at the boundary regions between the R and G lights and between the G and B lights, a colored light containing a P-polarization component is mixed with the R light that is supposed to be S-polarized in the shorter wavelength band of the R light (RP 1 ) in a transitional region between the P-polarization and the S-polarization, and a colored light containing a P-polarization component is mixed with the G light that is supposed to be S-polarized in the longer wavelength band of the G light (GS 1 ). Similarly, a colored light containing the P-polarization component is mixed with the G light that is supposed to be S-polarized in the shorter wavelength band of the G light (GP 1 ), and a colored light containing the P-polarization component is mixed with the B light that is supposed to be S-polarized in the longer wavelength band of the B light (BS 2 ). Thus, the pixel shift may cause color mixtures if there are mixtures of the P-polarization and S-polarization, to degrade the image quality.
[0021] Such a problem may also occur also when the color synthesizer is comprised of a polarizing beam splitter.
DISCLOSURE OF THE INVENTION
[0022] It is a therefore primary object of the present invention to provide an image display device capable of displaying a high quality and high resolution image without causing color irregularities, and adapted to be assembled easily and at low cost.
[0023] To this end, a first aspect of the present invention resides in an image display device comprising: a plurality of spatial light modulation elements illuminated by lights of different colors for performing an image modulation; a color synthesizer for synthesizing image lights modulated by said spatial light modulation elements, respectively; an incident polarized light controller for converting at least one of said plurality of image lights of different colors projected to said color synthesizer, into a different polarization than those of the other image lights; a pixel shift device comprised of at least one set of a polarization conversion element and a double refraction plate, said pixel shift device being for selectively shifting the optical paths of the image lights synthesized by said color synthesizer; wherein a color-selective polarization converter is arranged between said polarization conversion element and said double refraction plate forming a first set in said pixel shift device, said color-selective polarization converter forming an integral unit together with said pixel shift device and aligning polarizations of said plurality of image lights from said polarization conversion element with each other, before the image lights are projected to said double refraction plate.
[0024] A second aspect of the present invention resides in the image display device according to the first aspect, wherein the color synthesizer comprises a dichroic prism.
[0025] A third aspect of the present invention relates to the image display device according to the first aspect, wherein said color synthesizer comprises a polarizing beam splitter.
[0026] A fourth aspect of the present invention resides in the image display device according to any one of the first to third aspects, wherein said plurality of spatial light modulation elements comprise three spatial light modulation elements for performing an image modulation for a red light, a green light and a blue light, and said green light is projected to said color synthesizer in P-polarization, while said red light and said blue light are projected to said color synthesizer in S-polarization.
[0027] A fifth aspect of the present invention resides in the image display device according to any one of the first to third aspects, wherein said plurality of spatial light modulation elements comprise a spatial light modulation element for performing an image modulation for a green light and a spatial light modulation element for selectively performing an image modulation for a red light and a blue light, and said green light is projected to said color synthesizer in P-polarization, while said red light and said blue light are projected to said color synthesizer in S-polarization.
[0028] A sixth aspect of the present invention resides in the image display device according any one of the first to fifth aspects, wherein each of said plurality of spatial light modulation elements is a transmissive spatial light modulation element.
[0029] A seventh aspect of the present invention resides in the image display device according to any one of the first to fifth aspects, wherein each of said plurality of spatial light modulation elements is a reflective spatial light modulation element.
[0030] An eighth aspect of the present invention resides in the image display device according to any one of the first to seventh aspects, wherein said color-selective polarization converter has such polarization conversion characteristics that it performs a polarization conversion for a light in a wavelength band not being overlapped with those of said lights of different colors which are not subjected to a polarization conversion by said color-selective polarization converter.
[0031] According to the present invention, since the color-selective polarization converter is arranged between the first set of the polarization conversion element and the double refraction plate of the pixel shift device so as to form an integral unit with the pixel shift device, and the color-selective polarization converter aligns the polarizations of the plurality of image lights from the polarization conversion element projected to the double refraction plate, a high quality and high resolution image can be displayed without causing color irregularities, besides that the color-selective polarization converter can be assembled in a simple manner and at low cost.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] FIG. 1 is a schematic diagram of an image display device according to a first embodiment of the present invention;
[0033] FIGS. 2( a ) and 2 ( b ) are diagrams explaining the pixel shift operation in the first embodiment;
[0034] FIG. 3 is a schematic diagram of an image display device according to a second embodiment of the present invention;
[0035] FIGS. 4( a ) and 4 ( b ) are diagrams explaining the pixel shift operation in the second embodiment;
[0036] FIG. 5 is a schematic diagram of an image display device according to a third embodiment of the present invention;
[0037] FIGS. 6( a ) and 6 ( b ) are diagrams explaining an image display device according to a fourth embodiment of the present invention;
[0038] FIG. 7 is a diagram showing a modification of the pixel shift device;
[0039] FIG. 8 is a diagram showing an example of the polarization conversion characteristics of the color-selective polarization converter;
[0040] FIG. 9 is a diagram showing a basic configuration of a pixel shift device;
[0041] FIG. 10 is a diagram showing a configuration of the relevant parts in a conventional image display device;
[0042] FIGS. 11( a ) and 11 ( b ) are diagrams explaining the pixel shift operation in the image display device of FIG. 10 ; and
[0043] FIG. 12 is a diagram showing an example of the polarization conversion characteristics of a laminated phase plate.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0044] The present invention will be explained below with reference to some preferred embodiments shown in the accompanying drawings.
First Embodiment
[0045] FIG. 1 is a schematic diagram of an image display device according to a first embodiment of the present invention. In this embodiment, three transmissive spatial light modulation elements are used, which are in the form of transmissive liquid crystal display elements, for example, and a dichroic prism is used as a color synthesizer. With reference to FIG. 1 , an illumination light from a white light source 1 , such as a mercury discharge lamp, is transmitted through an integrator optical system 2 and projected to a dichroic mirror 3 such that the R light is transmitted whereas the lights of other wavelengths are reflected to separate the R light.
[0046] The R light separated by the dichroic mirror 3 is projected, via reflecting mirrors 4 and 5 , to a spatial light modulation element 6 R for the R light as an illumination light, so that the R light is subjected to an image modulation and projected to a dichroic prism 7 as a color synthesizer.
[0047] The lights reflected on the dichroic mirror 3 , on the other hand, are projected to a dichroic mirror 8 so that the B light is transmitted whereas the G light is reflected, thereby separating the B and G lights from each other. The B light from the dichroic mirror 8 is projected, via a reflecting mirror 9 , to a spatial light modulation element 6 B for the B light as an illumination light, so that the B light is subjected to an image modulation and then projected to the dichroic prism 7 .
[0048] The G light separated by the dichroic mirror 8 is projected, via a reflecting mirror 11 , to a spatial light modulation element 6 G for the G light as an illumination light after the polarization plane thereof has been rotated by 90 degrees by means of a half-wavelength plate 10 as an incident polarized light controller, so that the G light is subjected to an image modulation and projected to the dichroic prism 7 .
[0049] The integrator optical system 2 may be of a type known, per se, comprised of an optical system including an integrator rod or a fly-eye lens for realizing a substantially uniform illumination intensity distribution of the illumination light for the spatial light modulation elements 6 R, 6 G and 6 B, and a P-S conversion element for converting the emitted light into a predetermined kind of linear polarization.
[0050] The dichroic prism 7 reflects the R light modulated by the spatial light modulation element 6 R, and the B light modulated by the spatial light modulation element 6 B, while transmitting the G light modulated by the spatial light modulation element 6 C; in order that the images of the R, G and B lights are synthesized and then emitted.
[0051] According to the present embodiment, the light emitted from the integrator optical system 2 is made into S-polarization. The spatial light modulation elements 6 R and 6 B are respectively illuminated with the R and B lights in S-polarization, and each modulated image light is then projected to the dichroic prism 7 in S-polarization. The spatial light modulation element 6 G, on the other hand, is illuminated with the G light in P-polarization since the polarization plane of the G light has been rotated by 90 degrees by means of a half-wavelength plate 10 . The modulated G light is then projected to the dichroic prism 7 in P-polarization. Accordingly, a wavelength shift may be made of the synthesized image lights due to incidence angle characteristics of a dichroic film 7 a of the dichroic prism 7 , so that color irregularities in a displaying image is prevented
[0052] The optical paths of the synthesized image lights from the dichroic prism 7 is shifted by a pixel shift device 15 , being synchronous with image modulation performed by the spatial light modulation elements 6 R, 6 G and 6 B. The image lights from the pixel shift device 15 is projected and displayed by means of a projector lens 16 onto a screen which is not illustrated.
[0053] In the present embodiment, the pixel shift device 15 is of a double-point pixel shift configuration comprising a set of a polarization conversion element 21 and a double refraction plate 22 . A laminated phase plate 25 as a color-selective polarization converter is provided between the polarization conversion element 21 and the double refraction plate 22 . The polarization plane of the G light is rotated by 90 degrees by means of this laminated phase plate 25 , and the polarizations of the R, G and B image lights from the polarization conversion element 21 are aligned with each other and then projected to the double refraction plate 22 .
[0054] The pixel shift device 15 is made into a unit by holding the polarization conversion element 21 and the double refraction plate 22 integrally with a holder member 31 . The laminated phase plate 25 is held with the holder member 31 together with the polarization conversion element 21 and the double refraction plate 22 to be made into a part of the unitized pixel shift device 15 . As the laminated phase plate, there may be used a “Color Select” (trade name; manufactured by Color Link Inc., USA).
[0055] When the polarization conversion element 21 included in the pixel shift device 15 comprises, e.g., a liquid crystal panel as in the present embodiment, the polarization conversion element 21 transmits the incident light without any conversion of polarization in an ON state where a required voltage is applied to the polarization conversion element 21 . On the other hand, in an OFF state where the voltage to the polarization conversion element 21 is shut off, the polarization conversion element 21 transmits the incident light while rotating the polarization plane of the incident light by 90 degrees.
[0056] Accordingly, in the ON state of the polarization conversion element 21 , the image lights synthesized by the dichroic prism 7 is projected to the laminated phase plate 25 without being subjected to rotation of the polarization plane at the polarization conversion element 21 , as shown in a schematic diagram in FIG. 2( a ). More specifically, since the G light is projected to the laminated phase plate 25 in P-polarization while the R and B lights are projected to the laminated phase plate 25 in S-polarization, only the polarization plane of the G light is rotated by 90 degrees by means of the laminated phase plate 25 and converted from P-polarization into S-polarization. Accordingly, the R, G and B image lights synthesized by the dichroic prism 7 is projected to the double refraction plate 22 in uniform S-polarization. Thus, each image light is transmitted through the double refraction plate 22 without being subjected, e.g., to an optical path shift.
[0057] On the other hand, in the OFF state of the polarization conversion element 21 , the image lights synthesized by the dichroic prism 46 are projected to the laminated phase plate 25 while being subjected to rotation of the polarization plane by means of the polarization conversion element 21 , as schematically shown in the diagram of FIG. 2( b ). More specifically, since the G light is projected to the laminated phase plate 25 in S-polarization while the R and B lights are projected to the laminated phase plate 25 in P-polarization, only the polarization plane of the G light is rotated by 90 degrees by means of the laminated phase plate 25 and thereby converted from S-polarization into P-polarization. Accordingly, the R, G and B image lights synthesized by the dichroic prism 7 are projected to the double refraction plate 22 in uniform P-polarization. Thus, each image light is transmitted through the double refraction plate 22 while being subjected to an optical path shift.
[0058] As described above, according to the present embodiment, the modulated images of the R and B lights are projected to the dichroic prism 7 in S-polarization while the modulated image of the G light is projected to the dichroic prism 7 in P-polarization, before the image lights are synthesized. The polarizations of the synthesized image lights are aligned with each other by means of the laminated phase film 25 and subjected to pixel shift. Therefore, it is possible to prevent color irregularities that may be otherwise caused by the incidence angle characteristics of the dichroic prism 7 , and to display an image of high quality and high resolution. Further, the pixel shift device 15 is made into a unit by integrally holding the polarization conversion element 21 and the double refraction plate with the holder member 31 , and the laminated phase plate 25 for aligning the polarizations of the synthesized image lights is provided between the polarization conversion element 21 and the double refraction plate 22 and held by the holder member 31 to be made into a part of the unitized pixel shift device 15 . Therefore, the polarization conversion element 21 , the laminated phase plate 25 and the double refraction plate 22 can be joined with an adhesive having a similar refractive index, which will make it possible to assemble it in a simple manner and at low cost without any need of applying an antireflective coating to the laminated phase plate 25 or cleaning the surface thereof.
Second Embodiment
[0059] FIG. 3 is a schematic diagram of an image display device according to a second embodiment of the present invention. In the present embodiment, three reflective spatial light modulation elements are used, which are in the form of reflective liquid crystal display elements or DMDs (digital micro mirror devices), for example, and a dichroic prism is used as a color synthesizer.
[0060] With reference to FIG. 3 , an illumination light emitted from a white light source 41 is transmitted through an integrator optical system 42 and is projected to a dichroic mirror 43 in P-polarization, so that the R light is reflected while the lights of other wavelengths are transmitted, thereby separating the R light.
[0061] The R light separated by the dichroic mirror 43 is projected to a polarizing beam splitter 44 and transmitted through a multiple layer 44 a thereof. The R light from this polarizing beam splitter 44 is projected to a spatial light modulation element 45 R for the R light as an illumination light to be subjected to an image modulation by the spatial light modulation element 45 R. The R light modulated by the spatial light modulation element 45 R is converted into S-polarization since the spatial light modulation element 45 R is a reflective one, and thus the R light is reflected on the multiple layer 44 a of the polarizing beam splitter 45 and is projected to the dichroic prism 46 as a color synthesizer.
[0062] The lights transmitted through the dichroic mirror 43 , on the other hand, are projected to a dichroic mirror 48 through a reflecting mirror 47 , so that the B light is transmitted while the G light is reflected, thereby separating the B and G lights from each other. The B light separated by the dichroic mirror 48 is projected to a polarizing beam splitter 49 and transmitted through a multiple layer 49 a thereof. The B light from the polarizing beam splitter 49 is projected to a spatial light modulation element 45 B for the B light as an illumination light, and subjected to an image modulation by the spatial light modulation element 45 B to be converted into S-polarization. The S-polarized B light modulated by the spatial light modulation element 45 B is reflected on the multiple layer 49 a of the polarizing beam splitter 49 and projected to the dichroic prisms 46 .
[0063] The polarization plane of the G light separated by the dichroic mirror 48 is rotated by 90 degrees by means of a half-wavelength plate 50 to be converted into S-polarization. The G light is then projected to a polarizing beam splitter 51 and reflected on a multiple layer 51 a thereof. The G light from the polarizing beam splitter 51 is projected to a spatial light modulation element 45 G for the G light as an illumination light, and subjected to an image modulation by the spatial light modulation element 45 G to be converted into P-polarization. The P-polarized G light modulated by the spatial light modulation element 45 G is transmitted through the multiple layer 51 a of the polarizing beam splitter 51 and projected to the dichroic prism 46 .
[0064] At the dichroic prism 46 , the S-polarized R light modulated by the spatial light modulation element 45 R and the S-polarized B light modulated by the spatial light modulation element 45 B are reflected while the P-polarized G light modulated by the spatial light modulation element 45 G is transmitted, and the images of the R, G and B lights are synthesized and emitted.
[0065] The polarizations of the image lights modulated by the spatial light modulation elements 45 R, 45 G and 45 B are aligned with each other with the use of a pixel shift device 15 and a laminated phase plate 25 . The pixel shift device 15 is of double-point pixel shift configuration and made into a unit comprising a set of a polarization conversion element 21 and a double refraction plate 22 which are integrally held by a holder member 31 . The laminated phase plate 25 is provided between the polarization conversion element 21 and the double refraction plate 22 and made into a part of the unitized pixel shift device 15 . The optical paths of the image lights are shifted thereby being synchronous with an image modulation, and the image lights are then projected by means of a projection lens 16 onto a screen which is not illustrated.
[0066] In the present embodiment, in the same way as in Embodiment 1, in the ON state of the polarization conversion element 21 , the image lights synthesized by the dichroic prism 46 are projected to the laminated phase plate 25 without being subjected to rotation of the polarization plane by the polarization conversion element 21 , as shown in a schematic diagram in FIG. 4( a ). More specifically, since the G light is projected to the laminated phase plate 25 in P-polarization while the R and B lights are projected to the laminated phase plate 25 in S-polarization, only the polarization plane of the G light is rotated by 90 degrees by means of the laminated phase plate 25 to be converted from P-polarization into S-polarization. With this, the R, G and B image lights synthesized by the dichroic prism 46 are projected to the double refraction plate 22 in uniform S-polarization. Thus, each image light is transmitted through the double refraction plate 22 without being subjected, e.g., to an optical path shift.
[0067] In the OFF state of the polarization conversion element 21 , on the other hand, the image lights synthesized by the dichroic prism 46 are projected to the laminated phase plate 25 while being subjected to rotation of the polarization plane at the polarization conversion element 21 , as shown in a schematic diagram in FIG. 4( b ). More specifically, since the G light is projected to the laminated phase plate 25 in S-polarization while the R and B lights are projected to the laminated phase plate 25 in P-polarization, only the polarization plane of the G light is rotated by 90 degrees by means of the laminated phase plate 25 to be converted from S-polarization into P-polarization. Accordingly, the R, G and B image lights synthesized by the dichroic prism 46 are projected to the double refraction plate 22 in uniform P-polarization. Thus, each image light is transmitted through the double refraction plate 22 while being subjected to an optical path shift.
[0068] With the present embodiment, therefore, it is possible to prevent color irregularities caused by incidence angle characteristics of the dichroic prism 46 and to display an image of high quality and high resolution. Further, because the laminated phase plate 25 is made into a part of the unitized pixel shift device 15 , it can be assembled in a simple manner and at low cost without any need of applying an antireflective coating to the laminated phase plate 25 or cleaning the surface thereof.
Third Embodiment
[0069] FIG. 5 is a schematic diagram of an image display device according to a third embodiment of the present invention. In the present embodiment, a transmissive spatial light modulation element for the G light and a transmissive spatial light modulation element shared for the R and B lights are used as spatial light modulation elements, and a polarizing beam splitter is used as a color synthesizer.
[0070] With reference to FIG. 5 , an illumination light emitted from a white light source 61 is transmitted through an integrator optical system 62 and emitted in S-polarization to be projected to a dichroic mirror 63 , whereby the G light is reflected while the lights of other wavelengths are transmitted, and the G light is thus separated.
[0071] The polarization plane of the G light separated by the dichroic mirror 63 is rotated by 90 degrees by means of a half-wavelength plate 64 as an incident polarized light controller to be converted into P-polarization. The G light is then projected to a spatial light modulation means 65 G for the G light and subjected to an image modulation. The modulated G light is projected to a polarizing beam splitter 66 as a color synthesizer and is emitted through a multiple layer 66 a thereof.
[0072] The lights transmitted through the dichroic mirror 63 , on the other hand, are projected to a dichroic mirror 67 so that the R light is reflected while the B light is transmitted, to thereby separate the R and B lights from each other. The R light separated by the dichroic mirror 67 is reflected on a dichroic mirror 69 via a shutter 68 , and projected to a spatial light modulation element 65 RB that is shared for both the R and B lights. The B light separated by the dichroic mirror 67 is passed through a reflecting mirror 70 , a shutter 71 and a reflecting mirror 72 , transmitted through the dichroic mirror 69 , and projected to the spatial light modulation element 65 RB.
[0073] The shutters 68 and 71 are controlled so as to be alternately opened and closed, so that the R and B lights are subjected to a time-shared image modulation and projected to the polarizing beam splitter in S-polarization.
[0074] Since a P-polarized light is transmitted through the polarizing beam splitter 66 while an S-polarized light is reflected thereon, the P-polarized G light modulated by the spatial light modulation element 65 G is transmitted through the multiple layer 66 a of the polarizing beam splitter 66 while the S-polarized R or B light modulated by the spatial light modulation element 65 RB is reflected on the multiple layer 66 a , so that the G light and the R light, or the G light and the B light, are synthesized and then emitted.
[0075] The polarizations of the synthesized R and G lights or the synthesized B and G lights emitted from the polarizing beam splitter 66 are aligned with each other with the use of the pixel shift device 15 and the laminated phase plate 25 , in the same way as in the above embodiment. The pixel shift device 15 is of double-point pixel shift configuration and made into a unit comprising a set of a polarization conversion element 21 and a double refraction plate 22 which are integrally held by a holder member 31 . The laminated phase plate 25 is provided between the polarization conversion element 21 and the double refraction plate 22 and made into a part of the unitized pixel shift device 15 . The optical paths of the image lights are shifted being synchronous with an image modulation, and the image lights are then projected by means of a projection lens 16 onto a screen which is not illustrated.
[0076] According to the present embodiment, in the ON state of the polarization conversion element 21 , the R and G image lights or the B and G image lights synthesized by the polarizing beam splitter 66 are projected to the laminated phase plate 25 without being subjected to rotation of the polarization plane at the polarization conversion element 21 . More specifically, since the G light is projected to the laminated phase plate 25 in P-polarization while the R or B light is projected to the laminated phase plate 25 in S-polarization, only the polarization plane of the G light is rotated by 90 degrees by means of the laminated phase plate 25 and thereby converted from P-polarization into S-polarization. With this, the R and G image lights or the B and G image lights synthesized by the polarizing beam splitter 64 are projected to the double refraction plate 22 in uniform S-polarization. Thus, each image light is transmitted through the double refraction plate 22 without being subjected to e.g. an optical path shift.
[0077] In the OFF state of the polarization conversion element 21 , on the other hand, the R and G image lights or the B and G image lights synthesized by the polarizing beam splitter 66 are projected to the laminated phase plate 25 while being subjected to rotation of the polarization plane at the polarization conversion element 21 . More specifically, since the G light is projected to the laminated phase plate 25 in S-polarization while the R or B light is projected to the laminated phase plate 25 in P-polarization, only the polarization plane of the G light is rotated by 90 degrees by means of the laminated phase plate 25 and thereby converted from S-polarization into P-polarization. Accordingly, the R and G image lights or the B and G image lights synthesized by the polarizing beam splitter 66 are projected to the double refraction plate 22 in uniform P-polarization. Thus, each image light is transmitted through the double refraction plate 22 while being subjected to an optical path shift. In this way, by modulating the G light and the time-shared R and B lights synchronously with the ON/OFF states of the polarization conversion element 21 of the pixel shift device 15 , an image of higher resolution can be displayed.
[0078] Accordingly, with the present embodiment, it is possible to prevent color irregularities caused by incidence angle characteristics of the polarizing beam splitter 66 and to display an image of high quality and high resolution. Further, since the laminated phase plate 25 is made into a part of the unitized pixel shift device 15 , the polarization conversion element 21 , it can be assembled in a simple manner and at low cost without any need of applying an antireflective coating to the laminated phase plate 25 or cleaning the surface thereof.
Fourth Embodiment
[0079] FIG. 6 is a diagram for explaining an image display device according to a fourth embodiment of the present invention. FIG. 6( a ) shows an overall schematic configuration, while FIG. 6( b ) shows a configuration of an example of a rotating color filter shown in FIG. 6( a ). In the present embodiment, a reflective spatial light modulation element for the G light and a reflective spatial light modulation element shared for the R and B lights are used as spatial light modulation elements, and a polarizing beam splitter is used as a color synthesizer.
[0080] With reference to FIG. 6( a ), an illumination light from a white light source 81 is transmitted through an integrator optical system 82 and emitted in S-polarization, and this S-polarized illumination light is transmitted through the rotating color filter 86 and a color-selective polarization conversion element 83 as an incident polarized light controller, and then projected to a polarizing beam splitter 84 as a color synthesizer.
[0081] The rotating color filter 86 comprises, for example as shown in a plan view of FIG. 6( b ), equally divided six regions of a circle, which are alternately provided therein with a color filter GB for transmitting the G and B lights therethrough, or a color filter GR for transmitting the G and R lights therethrough. With rotation of the rotating color filter 86 , the GB light and the GR light are switched in a time-shared manner. Here, the color-selective polarization conversion element 83 converts the G light into P-polarization, and it may be the laminated phase plate explained in the above embodiment.
[0082] P-polarized light is transmitted through the polarizing beam splitter 84 while S-polarized light is reflected thereon. G light included in GB illumination light or GR illumination light projected to the polarizing beam splitter 84 in a time-shared manner, which has been converted into P-polarization by means of the color-selective polarization conversion element 83 , is transmitted through a multiple layer 84 a and projected to a reflective spatial light modulation element 85 G for the G light, whereby the G light is subjected to an image modulation and converted into S-polarization. The S-polarized G light modulated by the spatial light modulation element 85 G is reflected on the multiple layer 84 a of the polarizing beam splitter 84 and emitted.
[0083] The S-polarized R or B light incident on the polarizing beam splitter 84 in a time-shared manner is reflected on the multiple layer 84 a and subjected to an image modulation by a reflective spatial light modulation element 85 RB shared for the R and B lights while being converted into P-polarization. The P-polarized R or B light modulated by the spatial light modulation element 85 RB is transmitted through the multiple layer 84 a of the polarizing beam splitter 84 and synthesized with the G light modulated by the spatial light modulation element 85 G to be emitted.
[0084] The polarizations of the synthesized R and G lights or the synthesized B and G lights emitted from the polarizing beam splitter 84 are aligned with each other with a pixel shift device 15 and a laminated phase plate 25 , in the same way as in the above embodiment. The pixel shift device 15 is of double-point pixel shift configuration and made into a unit comprising a set of a polarization conversion element 21 and a double refraction plate 22 which are integrally held by a holder member 31 . The laminated phase plate 25 is provided between the polarization conversion element 21 and the double refraction plate 22 and made into a part of the unitized pixel shift device 15 . The optical paths of the image lights are shifted thereby being synchronous with an image modulation, and the image lights are then projected by means of a projection lens 16 onto a screen which is not illustrated.
[0085] According to the present embodiment, in the ON state of the polarization conversion element 21 , the R and G image lights or the B and G image lights synthesized by the polarizing beam splitter 84 are projected to the laminated phase plate 25 without being subjected to rotation of the polarization plane by the polarization conversion element 21 . More specifically, since the G light is projected to the laminated phase plate 25 in the S-polarization while the R or B light is projected to the laminated phase plate 25 in the P-polarization, only the polarization plane of the G light is rotated by 90 degrees by means of the laminated phase plate 25 and converted from the S-polarization into the P-polarization. In this instance, the R and G image lights or the B and G image lights synthesized at the polarizing beam splitter 84 are projected to the double refraction plate 22 in alignment with the P-polarization. Thus, each image light is transmitted through the double refraction plate 22 while being subjected, for example, to an optical path shift.
[0086] In the OFF state of the polarization conversion element 21 , on the other hand, the R and G image lights or the B and G image lights synthesized by the polarizing beam splitter 84 is projected to the laminated phase plate 25 while being subjected to rotation of the polarization plane at the polarization conversion element 21 . More specifically, since the G light is projected to the laminated phase plate 25 in G-polarization while the R or B light is projected to the laminated phase plate 25 in S-polarization, only the polarization plane of the G light is rotated by 90 degrees by means of the laminated phase plate 25 to be converted from P-polarization into S-polarization. Accordingly, the R and G image lights or the B and G image lights synthesized by the polarizing beam splitter 84 are projected to the double refraction plate 22 in uniform S-polarization. Thus, each image light is transmitted through the double refraction plate 22 without being subjected to an optical path shift. In this way, by modulating the G light and the time-shared R and B lights synchronously with the ON/OFF states of the polarization conversion element 21 of the pixel shift device 15 , it is possible to display a high resolution image.
[0087] With the present embodiment, as well as with the third embodiment, it is possible to prevent color irregularities that may be otherwise caused by incidence angle characteristics of the polarizing beam splitter 84 , and to display an image of high quality and high resolution. Further, since the laminated phase plate 25 is made into a part of the unitized pixel shift device 15 , the polarization conversion element 21 , it can be assembled in a simple manner and at low cost without any need of applying an antireflective coating to the laminated phase plate 25 or cleaning the surface thereof.
[0088] The present invention is not limited to the embodiments described above, and various modifications or changes may be made without departing from the scope of the invention. For example, the pixel shift device 15 is not limited to the double-point pixel shift configuration having a set of a polarization conversion element 21 and a double refraction plate 22 , and there may be applied a four-point pixel shift configuration shown in FIG. 7 , in which two sets of polarization conversion elements 21 a , 21 b and double refraction plates 22 a , 22 b are held integrally with a holder member 31 as a part of the unitized pixel shift device. Further, the pixel shift device 15 may be of a six-point pixel shift configuration in which not less than three sets of polarization conversion elements and double refraction plates are held integrally with a holder member as a part of the unitized pixel shift device, so as to allow pixel shift configurations of not less than six points. In case where the pixel shift device 15 is made into an integral unit comprising a plurality of sets of polarization conversion elements and double refraction plates, a color-selective polarization converter 25 is preferably arranged between the polarization conversion element 21 a and the double refraction plate 22 a of the first set of the pixel shift device 15 as a part of the unitized pixel shift device 15 , as illustrated in FIG. 7 .
[0089] Moreover, the light source of the illumination light is not limited to a white light source, and colored light sources such as LEDs for emitting R, G and B lights may also be used. The color-selective polarization converter provided integrally with the pixel shift device may convert a polarization of the R or B light instead of that of the G light. Further, the color-selective polarization converter may also be configured to have such polarization conversion characteristics that a light in a wavelength band subjected to polarization conversion is not overlapped with a light in a wavelength band not subjected to polarization conversion, as shown in FIG. 8 . In this instance, since the P-polarized component is not mixed with the S-polarized component in the wavelength regions ranging from the longer wavelength band of the B light to the shorter wavelength band of the G light, and from the longer wavelength band of the G light to the shorter wavelength band of the R light, a pixel shift can be made without color mixtures, thereby allowing an image of higher quality to be displayed. In addition, instead of controlling polarization conversion characteristics of the color-selective polarization converter, similar effects may also be achieved by controlling the reflection characteristics or transmission characteristics of a coating applied on the optical elements such as a dichroic prism, a polarizing beam splitter or a dichroic mirror so that the wavelength bands of R, G and B are not overlapped. Further, when a colored light source such as an LED is used, similar effects may be achieved by using narrow-banded colored light sources so that the illumination wavelength bands of R, G and B are not overlapped.
LISTING OF REFERENCE NUMERALS
[0000]
1 white light source
2 integrator optical system
3 , 8 dichroic mirror
4 , 5 , 9 , 11 reflecting mirror
6 R, 6 G, 6 B spatial light modulation element
7 dichroic prism
10 half-wavelength plate
15 pixel shift device
16 projection lens
21 , 21 a , 21 b polarization conversion element
22 , 22 a , 22 b double refraction plate
25 laminated phase plate
31 holder member
41 white light source
42 integrator optical system
43 , 48 dichroic mirror
44 , 49 , 51 polarizing beam splitter
44 a , 49 a , 51 a multiple layer
45 R, 45 G, 45 B spatial light modulation element
66 polarizing beam splitter
66 a multiple layer
68 , 71 shutter
70 , 72 reflecting mirror
81 white light source
82 integrator optical system
83 color-selective polarization conversion element
84 polarizing beam splitter
85 G, 85 R, 85 B spatial light modulation element
86 rotating color filter
91 color-selective polarization converter | An image display device for displaying a high quality and high resolution image without causing color irregularities, adapted to be assembled simply and at low cost. The device includes a plurality of spatial light modulation elements ( 6 R, 6 G; 6 B) illuminated by lights of different colors for performing an image modulation; a color synthesizer ( 7 ) for synthesizing image lights modulated by each of the spatial light modulation elements; an incident polarized light controller ( 10 ) for converting at least one of the plurality of image lights of different colors projected to the color synthesizer, into a different polarization than those of the other image lights; and a pixel shift device ( 15 ) that includes at least one set of a polarization conversion element ( 21 ) and a double refraction plate ( 22 ). The pixel shift device ( 15 ) selectively shifts the optical paths of the image lights synthesized by the color synthesizer. A color-selective polarization converter ( 25 ) is arranged between the polarization conversion element ( 21 ) and the double refraction plate ( 22 ) forming a first set in the pixel shift device ( 15 ). The color-selective polarization converter ( 25 ) forms an integral a unit with the pixel shift device and aligning polarizations of the plurality of image lights from the polarization conversion element ( 21 ) to each other before the image lights are projected to the double refraction plate ( 22 ). | 7 |
FIELD OF INVENTION
This invention relates to a process for the upgrading of hydrocarbon streams. More particularly the invention relates to a process for upgrading gasoline boiling range petroleum fractions containing substantial proportions of sulfur impurities.
BACKGROUND OF THE INVENTION
The removal of sulfur from petroleum fractions represents a major challenge in petroleum refining. Sulfur compounds, such as hydrogen sulfide, mercaptans, thiophenes, and elemental sulfur are impurities in petroleum fractions. If these impurities not removed from petroleum fractions, these sulfur impurities will corrode process equipment, impart poor color and odor properties to products, and poison downstream catalytic processes. The environmental impact of sulfur in various refining products may also be significant. For example, even though the current level of sulfur in motor gasoline is limited to less than 0.10 wt %, there are indications that even this level is not low enough to meet future standards for emissions from automobile exhaust. In a modem U.S. refinery, roughly over 50% of the gasoline pool comprises cracked gasoline produced from a fluid catalytic cracking (FCC) process. This makes FCC gasoline a major part of the gasoline product pool in the United States. Because FCC gasoline is produced from the heaviest and often the most sulfur-contaminated streams in the refinery, it provides a large portion of the sulfur in the gasoline product pool. The reduction of sulfur in gasoline, particularly to levels such as 300 ppm-wt as required to comply with environmental regulations are said to reduce automobile exhaust emissions of carbon monoxide, nitrogen oxides and hydrocarbons as well as sulfur oxides.
Naphthas and other light fractions such as heavy cracked gasoline may be hydrotreated by passing the feed over a hydrotreating catalyst at elevated temperature and somewhat elevated pressure in a hydrogen atmosphere. One suitable family of catalysts which has been widely used for this service is a combination of a Group VIII and a Group VI element, such as cobalt and molybdenum, on a substrate such as alumina. After the hydrotreating operation is complete, the product may be fractionated, or simply flashed, to release the hydrogen sulfide and collect the now sweetened gasoline.
Cracked naphtha, as it is produced from the FCC and without any further treatments such as purifying operations, has a relatively high octane number as a result of the presence of olefinic components. In some cases, this fraction may make a significant contribution to product octane. Hydrotreating of any of the sulfur-containing fractions which boil in the gasoline boiling range causes a reduction in the olefin content and, consequently, a reduction in the octane number. As the degree of desulfurization increases, the octane number of the normally liquid gasoline boiling range product decreases. Some of the hydrogen may also cause some hydrocracking as well as olefin saturation, depending on the conditions of the hydrotreating operation further lowering the octane of the fraction.
U.S. Pat. No. 2,514,997 to Floyd discloses a process for the removal of sulfur from a non-aromatic hydrocarbon feed using a solvent comprising a poly-olefin glycol having a molecular weight in the range of about 400 to 4,000 to produce a raffinate phase being substantially sulfur free.
U.S. Pat. No. 3,957,625 to Orkin discloses that the sulfur impurities tend to concentrate in the heavy portion of the cracked gasoline fraction. Orkin discloses a process wherein the cracked gasoline is fractionated to separate the heavy fraction of the catalytically cracked gasoline and hydrotreating the heavy fraction. Orkin does not attempt to recover octane lost in the hydrotreating of the heavy fraction.
Processes for removing sulfur without reducing the octane of the FCC gasoline and similar streams are disclosed in U.S. Pat. Nos. 5,298,150 and 5,290,427 Fletcher et al. wherein sulfur containing fraction of the FCC gasoline is desulfurized and the desulfurized fraction is contacted with an acidic catalyst to restore the octane of the desulfurized fraction. This process requires an energy intensive fractionation of the entire cracked gasoline stream to obtain the higher boiling fraction which contains the bulk of the sulfur impurities in the cracked gasoline.
U.S. Pat. No. 2,634,230 to Arnold et al. discloses a process for the desulfurization of high sulfur olefinic naphtha which Arnold teaches is the most difficult to desulfurize or otherwise refine by conventional methods. In the process 2,4-dimethyl sulfolane is employed to extract sulfur from a highly olefinic naphtha, such that the solvent does not affect separation between olefins and paraffins, to provide a sulfur lean raffinate phase and a sulfur rich extract. Both the raffinate and extract phases are distilled to remove the solvent and provide a dewatered raffinate and a dewatered extract. The dewatered extract is catalytically desulfurized and the resulting desulfurized extract is blended with the dewatered raffinate to provide a desulfurized naphtha product. Although Arnold avoids a costly fractionation step on the cracked gasoline stream, Arnold's process includes the costly distillation of both the extract and the raffinate streams to recover the sulfolane solvent.
U.S. Pat. No. 2,664,385 to Wolff et al. discloses a process for the extraction of organic sulfur compounds from a mixture thereof with hydrocarbons wherein the mixture is contacted with an ester of a thiosulfonic acid containing 2 to 20 hydrocarbons per molecule to provide a raffinate phase and an extract phase comprising the ester and the organic sulfur compound.
U.S. Pat. No. 2,956,946 to King et al. relates to a solvent extraction process for the removal of acid oils such as alkylated phenols, aerosols, xylenols, thiophenols and the like from petroleum distillates boiling between about 100° F. and about 900° F. by employing an ethylene glycol monoalkylamine ether to extract the acid oils and recover an acid-free raffinate. King et al. discloses that the acid oils were extracted by the solvents in preference to aromatics regardless of the conditions employed. King et al. discloses a process whereby the feedstream containing the acid oils is contacted in an extraction zone with a solvent to provide a raffinate stream and a rich solvent stream. The raffinate stream is water washed to provide a treated petroleum distillate and a water and solvent stream. The water and solvent stream is passed to a settling zone where the water and solvent stream is contacted with the rich solvent stream to provide an aromatics fraction and a second rich solvent stream. The second rich solvent stream is passed to a distillation column to separate water from the second rich solvent stream to provide an anhydrous rich solvent stream. The anhydrous rich solvent stream is passed to a vacuum tower to separate the acid oils and to provide a lean solvent stream. The lean solvent stream and a portion of the anhydrous rich solvent stream are returned to the extraction zone.
U.S. Pat. No. 2,792,332 to Hutchings discloses a process for the removal of aromatics and sulfur compounds from a feedstream comprising heavy naphtha, aromatics and sulfur compounds wherein the feedstream comprising heavy naphtha is contacted in a first extraction column with a solvent combination comprising isopropyl alcohol and polyethylene glycol having a molecular weight of about 600, in volume percent ratio of about 70 to 30 of glycol to alcohol, respectively, to obtain a concentrated aromatic fraction and a paraffinic-naphthenic raffinate. Hutchings recycles the raffinate for reprocessing with the feedstream. The raffinate is first distilled to remove the alcohol, and the resulting alcohol depleted raffinate is water washed to remove traces of the polyethylene glycol 600 and then dried. The extract phase is similarly processed to first remove the alcohol by distillation and the alcohol-free extract is steam distilled to recover an aromatic product and to provide an aromatic-free polyethylene glycol/water stream. The polyethylene glycol/water stream is then passed to a solvent recovery tower to distill off the remaining water. In a second extraction column, the concentrated aromatic fraction is contacted with pure polyethylene glycol to recover an aromatic extract and the aromatic extract is steam distilled to provide a purified aromatic product comprising aromatic sulfur-type compounds.
U.S. Pat. No. 4,781,820 to Forte and U.S. Pat. No. 4,498,980 to Forte et al. disclose processes for the separation of aromatic and non-aromatic hydrocarbons from a mixed hydrocarbon feed wherein the feedstream is contacted with a solvent comprising a polyalkylene glycol and a co-solvent comprising a glycol ether. The U.S. Pat. Nos. 4,781,820 and 4,498,980 are hereby incorporated by reference.
In any case, regardless of the mechanism by which it happens, the decrease in octane which takes place as a consequence of sulfur removal by hydrotreating creates a conflict between the growing need to produce gasoline fuels with higher octane number and--because of current ecological considerations - the need to produce cleaner burning, less polluting fuels, especially low sulfur fuels.
Processes are sought for the efficient removal of sulfur compounds from FCC gasoline and similar petroleum refinery streams without the loss of gasoline octane yield and quality, and at a minimum reprocessing cost.
SUMMARY
It is a broad object of this invention to provide an effective means for removing sulfur contaminants from petroleum streams such as FCC gasoline. By the process of the present invention the sulfur contaminants are efficiently concentrated into a smaller stream and the much smaller stream may be further treated in a mild desulfurization step to remove the sulfur without the accompanying loss of valuable octane quality.
In one embodiment the invention relates to a process for the removal of sulfur impurities from a mixture thereof with FCC gasoline. The process comprises contacting the mixture in an extraction zone with a lean solvent including a component selected from the group consisting of a poly alkylene glycol, a polyalkylene glycol ether, and mixtures thereof having a molecular weight less than about 400 to provide a raffinate stream having a reduced sulfur content relative to the mixture and a rich-solvent stream enriched in the sulfur impurities. The rich-solvent stream is passed to a stripping zone wherein the rich-solvent stream is contacted with a stripping medium to produce an extract phase comprising sulfur impurities and a stripped solvent stream depleted of the impurities. The extract phase is separated into an extract product and a first aqueous phase. The raffinate stream is washed with at least a portion of the first aqueous phase to provide a raffinate product and a second aqueous phase. At least a portion of the second aqueous phase is passed to the stripping zone as the stripping medium. At least a portion of the stripped solvent stream is returned to the extraction zone as the lean solvent.
In a further embodiment the invention is a process for the extraction of sulfur compounds from a hydrocarbon feedstream comprising FCC gasoline and sulfur compounds. The process comprises passing the hydrocarbon feedstream to an extraction zone and therein contacting the feedstream with a first lean selective solvent including a component selected from the group consisting of tetraethylene glycol, penta ethylene glycol, methoxytriglycol, and mixtures thereof to provide a rich-solvent stream enriched in sulfur relative to the hydrocarbon feedstream and a raffinate stream. The rich-solvent stream is passed to a reboiled flash zone to provide a first overhead stream and a second rich-solvent stream. The second rich-solvent stream is passed to a reboiled distillation zone and therein the second rich-solvent stream is contacted with a stripping medium to provide a second lean solvent stream and a second overhead stream comprising hydrocarbons and sulfur compounds. The first overhead stream and at least a portion of the second overhead stream are admixed to provide a mixed overhead stream. The mixed overhead stream is cooled and condensed to provide a sulfur-rich hydrocarbon stream and a first aqueous stream. At least a portion of the first aqueous stream is admixed with the raffinate stream to provide a raffinate admixture. The raffinate admixture is cooled and condensed to provide a lean hydrocarbon stream and a second aqueous stream. At least a portion of the second aqueous stream is passed to the reboiled distillation zone to provide the stripping medium. At least a portion of the second lean solvent stream is returned to the extraction zone to provide the first lean solvent stream.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a process flow diagram of the process arranged in accordance with the present invention
DETAILED DESCRIPTION
The feed to the process comprises a sulfur-containing petroleum fraction which boils in the gasoline boiling range. Feeds of this type include light naphthas typically having a boiling range of about C 6 to 330° F. (166° C.); full range naphthas, typically having a boiling range of about C 5 to 420° F. (216° C.), heavier naphtha fractions boiling in the range of about 260° F. (127° C.) to 412° F. (211° C.), or heavy gasoline fractions boiling at, or at least within, the range of about 330° (166° C.) to 500° F. (260° C.), preferably about 330° F. (166° C.) to 412° F. (211° C.). While the most preferred feed appears to be a heavy gasoline produced by catalytic cracking; or a light or full range gasoline boiling range fraction, the best results are obtained when, as described below, the process is operated with a gasoline boiling range fraction which has a 95 percent point (determined according to ASTM D 86) of at least about 325° F. (163° C.) and preferably at least about 350° F. (177° C.), for example, 95 percent points of at least 380° F. (about 193° C.) or at least about 400° F. (about 220° C.).
The process may be operated with the entire gasoline fraction obtained from the catalytic cracking step or, alternatively, with part of it, depending on the amount and the identity of the sulfur compounds present. If the front end of the cracked fraction contains relatively few sulfur components, it may be possible to separate the higher boiling fractions and process them through the steps of the present process without processing the lower boiling cut. The cut point between the treated and untreated fractions may vary according to the sulfur compounds present but usually, a cut point in the range of from about 100° F. (38° C.) to about 300° F. (150° C.), more usually in the range of about 200° F. (93° C.) to about 300° F. (150° C.) will be suitable. The exact cut point selected will depend on the sulfur specification for the gasoline product as well as on the type of sulfur compounds present; lower cut points will typically be necessary for lower product sulfur specifications.
The sulfur which is present in components boiling below about 150° F. (65° C.) is mostly in the form of mercaptans which may be removed by extractive type processes which convert the mercaptans to disulfides and extract the disulfides, but hydrotreating is appropriate for the removal of thiophene and other cyclic sulfur compounds present in higher boiling components, e.g., component fractions boiling above 180° F. (82° C.). Typically, the mercaptan sulfur will include methyl mercaptan, ethyl mercaptan, propyl mercaptan, butyl mercaptan, higher mercaptans, and mixtures thereof; and the concentration of mercaptan sulfur compounds in the hydrocarbon feedstream will range from about 1 to about 500 ppm wt. Treatment of the lower boiling fraction in an extractive type process coupled with hydrotreating of the higher boiling component may therefore represent a preferred economic process option. Higher feed cut points will be preferred in order to minimize the amount of feed which is passed to the hydrotreater and the final selection of cut point together with other process options such as the extractive type desulfurization will therefore be made in accordance with the product specifications, feed constraints and other factors.
The sulfur content of these catalytically cracked fractions will depend on the sulfur content of the feed to the cracker as well as on the boiling range of the selected fraction used as the feed in the process. Lighter fractions, for example, will tend to have lower sulfur contents than the higher boiling fractions. As a practical matter, the sulfur content will exceed 50 ppm-wt and usually will be in excess of 100 ppm-wt and in most cases in excess of about 500 ppm-wt. For the fractions which have 95 percent points over about 380° F. (193° C.), the sulfur content may exceed about 1,000 ppm-wt and may be as high as 4,000 to 5,000 ppm-wt or even higher, as shown below. The nitrogen content is not as characteristic of the feed as the sulfur content and is preferably not greater than about 20 ppm-wt although higher nitrogen levels typically up to about 50 ppm-wt may be found in certain higher boiling feeds with 95 percent points in excess of about 380° F. (193° C.). The nitrogen level will, however, usually not be greater than 250 or 300 ppm-wt. As a result of the cracking which has preceded the steps of the present process, the feed to the hydrodesulfurization step will be olefinic, with an olefin content of at least 5 and more typically in the range of 10 to 20, e.g. 15-20, weight percent.
In the process of the present invention, the extract stream, a much smaller stream than the feed to the extraction zone, will be enriched in sulfur compounds and aromatic hydrocarbons relative to the fraction of the FCC gasoline being treated. The extract stream is further processed in a mild hydrotreating zone to remove the sulfur compounds providing a hydrotreated extract stream without significantly altering the octane number of the recombined raffinate and hydrotreated extract stream by hydrotreating at conditions which do not saturate the aromatic content of the extract stream. Although some of the olefins in the extract will be converted to paraffins in the mild hydrotreating step, the overall loss of the total FCC gasoline will be minimal when the hydrotreated extract is recombined with the raffinate in the gasoline pool. The mild hydrotreating step may be carried out in the conventional manner by passing the extract stream at a temperature ranging from about 220° C. to about 450° C. and a pressure ranging from about 445 kPa to about 10.4 MPa (50 psia to 1500 psia) over a conventional desulfurization catalyst prepared from a Group VI and/or a Group VIII metal on a suitable substrate. Combinations such as Ni--Mo or Co--Mo are typical. The support for the desulfurization catalyst is conventionally an alumina, or silica-alumina, but other porous solids such as magnesia, titania or silica--either alone or mixed with alumina or silica-alumina--may be used. The space velocity-for the mild hydrodesulfurization step is typically about 0.5 to about 10 LHSV (hr- 1 ), based on the total feed and the total catalyst volume. The hydrogen to hydrocarbon ratio in the feed is typically about 500 to about 5000 SCF/Bbl (about 90 to 900 N1/1) based on the total feed to the hydrotreater and hydrogen volumes. The extent of desulfurization will depend on the extract sulfur content and the product sulfur specification.
SOLVENTS
Solvents acceptable for the instant invention should be able to remove sulfur compounds, particularly organosulfur components such as mercaptans, sulfides, disulfides, thiophenes, benzothiophenes, and mixtures thereof from hydrocarbon feedstreams derived from petroleum fractions in the gasoline boiling range. The selective solvent of the present invention selectively removes sulfur compounds such as mercaptans, sulfides, thiophenes, and mixtures thereof from a hydrocarbon feedstream. The liquid-liquid extraction zone may operate at a capacity and efficiency necessary to remove essentially all of the sulfur compound impurities. The selective solvents employed in the instant invention, in general, are water-miscible organic liquids at the operating temperature of the process. Furthermore, the selective solvents must have a boiling point and a decomposition temperature higher than the operating temperature of the process, wherein the operating temperature of the process refers to the liquid-liquid extraction temperatures at which the feedstock is contacted with the solvent. The term "water-miscible" describes those solvents which are completely miscible with water over a wide range of temperatures, which have a high partial miscibility with water at room temperature, and which are completely miscible with water at operating temperatures. By the term "essentially all of the sulfur compounds," it is meant that the sulfur content of the treated stream is preferably less than 200 ppm-wt sulfur and more preferably that it is less than 100 ppm-wt, and most preferably that it is less than 50 ppm-wt.
The selective solvents employed in the instant invention are low molecular weight, preferably having a molecular weight less than about 400 and more preferably having a molecular weight less than about 200. Examples of such solvents include polyalkylene glycols of the formula:
HO--[CHR.sub.1 --(CR.sub.2 R.sub.3).sub.n --O--].sub.m --H
wherein n is an integer from 1 to 5 and is preferably the integer 1 or 2; m is an integer having a value of 1 or greater, preferably between about 1 to about 20 and most preferably between about 1 and about 8; and wherein R 1 , R 2 , and R 3 may be hydrogen, arkyl, aryl, aralkyl or alkylaryl and are preferably hydrogen and alkyl having between 1 and about 10 carbon atoms and most preferably are hydrogen. Examples of the polyalkylene glycol solvents employable herein are diethylene glycol, triethylene glycol, tetraethylene glycol, pentaethylene glycol, 1,3-butane glycol, 1,2-butane glycol, 1,5-pentane glycol, water, and mixtures thereof and the like. In addition to the polyalkylene glycol solvents, the solvent may be selected from the group consisting of sulfolane, furfural, n-formyl morpholine, n-methyl-2pyrrolidone. Preferred solvents are diethylene glycol, triethylene glycol, tetraethylene glycol, pentaethylene glycol, water, and mixtures thereof, with pentaethylene glycol being most preferred. In addition, such solvents may be combined with a cosolvent component having a low molecular weight, preferably less than 400 and more preferably having a molecular weight less than about 200. Examples of such cosolvents include a glycol ether of the formula:
R.sub.4 O--[CHR.sub.5 --(CHR.sub.6).sub.x --O].sub.y --R.sub.7
wherein R 4 , R 5 , R 6 , and R 7 may be hydrogen, alkyl, aryl, aralkyl, alkylaryl, and mixtures thereof with the proviso that R 4 or R 7 are not both hydrogen. The value of x is an integer from 1 to 5 preferably 1 or 2 and y may be an integer from 1 to 10 and is preferably from 2 to 8, and most preferably from 2 to 5 R 4 , R 5 , R 6 , and R 7 are preferably selected from the group consisting of hydrogen and alkyl having 1 to about 10 carbons with the proviso that R 4 and R 7 may not both be hydrogen and most preferably R 4 is alkyl having from 1 to 5 carbons and R 5 , R 6 , and R 7 are hydrogen.
DESCRIPTION OF THE DRAWING
The process of the present invention is hereinafter described with reference to the drawing which illustrates various aspects of the process. It is to be understood that no limitation to the scope of the claims which follow is intended by the following description. Those skilled in the art will recognize that these process flow diagrams have been simplified by the elimination of many necessary pieces of process equipment including some heat exchangers, process control systems, pumps, fractionation systems, etc. It may also be discerned that the process flow depicted in the figures may be modified in many aspects without departing from the basic overall concept of the invention.
With reference to the figure, a feedstream comprising an FCC gasoline with compounds including organosulfur components is passed via line 10 to a recovery zone 100. In this context, the amount of sulfur in the FCC gasoline ranges between 50 and 3000 ppm-wt sulfur. In the recovery zone 100, the feedstream 10 is contacted with a lean solvent in line 14 which has been chilled in cooler 102 to a temperature of between 50° C. and 200° C. A raffinate stream in line 12--being essentially free of mercaptans and sulfides is withdrawn from the top of the recovery zone and passed to a water-wash zone 300 via lines 12, 18 and 20. An in-line mixer 112 facilitates the admixing of the raffinate in line 12 with wash water stream 66. The wash water stream 66 is introduced to the raffinate stream in line 12 to remove any traces of the solvent which might have remained in stream 18 and the resulting mixture is separated in water-wash zone 300 into a product stream which is withdrawn in line 21 and a water phase which is withdrawn in line 22. A rich solvent stream is withdrawn from the recovery zone 100 via line 16 and passed to a reboiled flash zone 103 wherein the rich solvent stream is heated and flashed by cross exchange with hot, lean solvent stream 38 and passed in line 47 to the top of a stripping zone 200. In the stripping zone the liquid from the reboiled flash zone is contacted with a stripping medium which is introduced to the stripping zone 200 via lines 60 and 62. A bottom stream is withdrawn from the stripping zone in line 35. A portion of the bottoms stream 35 is passed via line 49 through reboiler 201 and reboiled bottoms 50 is returned to the stripping zone 200. The net bottoms 37 is passed through pump 303 and via line 38 to reboiled flash zone 103 wherein heat from the bottoms stream 38 is transferred to the rich solvent stream 16 to at least partially vaporize the rich solvent stream in line 47. This cross exchange of heat results in a first cooled lean solvent stream in line 46 which is then passed to cooler 102 which further cools the lean solvent stream and provides the lean solvent stream in line 14 which is returned to the recovery zone 100 as hereinabove described. A vapor stream 48 is produced in the reboiled flash zone 103 acting as a kettle reboiler wherein a portion of the rich solvent is vaporized which then serves to further cool the first cooled lean solvent stream 46. The overhead vapor stream 24 from the stripping zone 200 is combined with the vapor stream 48 withdrawn from the reboiled flash zone 103 and the admixture is passed via line 26 to overhead condenser 105. A cooled overhead stream in line 28 is passed to accumulator 104. In accumulator 104 the hydrocarbon phase is withdrawn via line 30 as the extract stream and the aqueous phase comprising water soluble sulfur compounds is passed via line 32 and combined with line 22 comprising solvent recovered from the raffinate wash 300 and the admixture is passed via lines 34 and 52 to a water still 106. The water still 106 by means of reboiling with such available medium as low pressure steam provides a rejected stream 54 comprising sulfur compounds which is passed overhead in line 54 to condenser 108 and the cooled overhead 55 is passed to accumulator 107. A condensed stream 68 comprising the sulfur compounds withdrawn from accumulator 107 may be passed to a refinery sour water system for further disposal. A portion of the condensed stream 56 is withdrawn from accumulator 107, admixed with line 34, and returned to the water still 106 in line 52. Vapor water stream 62 is returned to the stripping zone 200 and liquid water stream 58 is split such that a portion is passed via line 60 to be returned to the stripping zone 200 and a portion is passed via lines 64 and 66 and pump 302 to provide wash water for the raffinate stream 12.
In the above described scheme, the recovery zone may be operated as a liquid-liquid extraction zone wherein the feed stream is introduced as a liquid hydrocarbon stream. In this operation, the liquid-liquid extraction zone 100 typically is operated at conditions to maintain all of the streams in liquid state. Such operation would include a pressure ranging from approximately 200 kPa (30 psia) to approximately 1.1 MPa (165 psia) and a temperature ranging from about 20° C. to approximately 200° C. The operation of the stripping zone 200 may be characterized by operating conditions including a pressure ranging from about 20 kPa (3 psia) to approximately 450 kPa (65 psia) and a temperature ranging from approximately 100° C. to approximately 250° C. The water still 114 is conventionally operated at temperatures ranging from 20° C. to approximately 140° C. and a pressure ranging from 20 kPa (3 psia) to approximately 450 kPa (65 psia).
In an alternate embodiment, referring to the above figure, stream 10 may be passed to the recovery zone 100 as a vaporized stream which is at least partially vaporized and the recovery zone is operated as a gas absorption zone having an absorption temperature ranging from 100° C. to about 235° C. and an absorption pressure ranging from 20 kPa to about 430 kPa.
The invention will be further clarified by a consideration of the following examples, which are intended to be purely exemplary of the use of the invention.
EXAMPLES
Other embodiments of the invention will be apparent to the skilled in the art from a consideration of this 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.
EXAMPLE I
A single-stage wash procedure for determining the degree of sulfur removal from a petroleum fraction in a single-stage of extraction was carried out in the following manner. A 100 ml sample of the hydrocarbon was poured into a 500 ml separatory funnel. An appropriate volume amount of solvent, according to a desired solvent to feed ratio was added to the funnel and the contents were mixed thoroughly for about 5 minutes. The phases were permitted to separate and the contents were mixed again for about 5 minutes. The mixing and phase separation were continued until the mixing time had reached a total of 25 minutes. The phases were collected and analyzed for the amount of hydrocarbon and sulfur in the solvent phase.
According to the above procedure, a sample of a light FCC gasoline with an ASTM initial boiling point (IBP) of 27° C. (80° F.) and an end point of about 82° C. (180° F.) containing about 2 vol-% aromatics, about 45% olefins and having a total sulfur content of 464 ppm-wt was evaluated with varying solvent to feed ratios for three solvents. The solvents tested were tetra-ethylene glycol (TETRA), pentaethylene glycol (PENTA), and a 75:25 mixture of tetraethylene glycol and methoxytriglycol (MIXED). The results are shown in Table 1 for solvent to feed ratios varying from 1:1 to 3:1. Determinations were made at 22° C. and at 60° C. for the TETRA solvent. At 22° C., the sulfur removal ranged from 28 to 49% as the solvent to feed ratio was increased from 1:1 to 3:1 and the amount of hydrocarbon in the solvent phase increased from 6 to 18 vol-%. At 60° C., the results for TETRA showed that for a 3:1 solvent to feed ratio, the sulfur removal increased to 57% and the entrained hydrocarbon phase was reduced to about 10 vol-%. Using the pentaethylene glycol (PENTA) solvent showed that the sulfur removal ranged from 38 to 72 wt-% for solvent to feed ratios from 1:1 to 3:1. Surprisingly, the MIXED solvent showed an even higher sulfur removal at the low solvent to feed ratio, 82 percent higher than TETRA alone and 34 percent higher than PENTA. At a solvent to feed ratio of 3:1 the use of the MIXED solvent resulted in a 75% sulfur removal with an entrainment of about 22% of the hydrocarbon phase, resulting in a hydrocarbon phase having a sulfur content of 150 ppm-wt. The molecular weights of the solvents tested ranged from about 187 to 240.
TABLE 1__________________________________________________________________________SOLVENT EXTRACTION OF LIGHT FCC GASOLINESulfur Content: 464 ppm-wt SINGLE WASH AT INDICATED VOLUME RATIO 1:1 2:1 3:1SOLVENT AVE MW T,°C. ppm HC % Sulf % ppm HC % Sulf % ppm HC % Sulf %__________________________________________________________________________TETRA 194.2 22 356 6% 28% 322 12% 39% 289 18% 49%TETRA 194.2 60 400 7% 20% 304 12% 42% 262 10% 57%PENTA 238.3 22 308 7% 38% 180 15% 67% 169 22% 72%MIXED 186.7 ave 22 246 8% 51% 197 17% 65% 150 22% 75%__________________________________________________________________________ TETRA Tetraethylene glycol PENTA Pentaethylene glycol MIXED 75 vol% TETRA/25 vol% methoxytriglycol
EXAMPLE II
A single-stage wash of the full boiling range FCC gasoline having a nominal ASTM IBP of 36° C. (96° F.), a 50% point of 99° C. (211° F.) and an end point of 217° C. (422° F.) with 22 vol-% aromatics and about 29 vol-% olefins and 677 ppm-wt sulfur was evaluated according to the procedure of Example I at 22° C. with TETRA, PENTA, and the MIXED solvents for solvent to feed ratios of 1:1 to 3:1. The results for the full boiling FCC gasoline are shown in Table 2. At the 1:1 solvent to feed ratio, the MIXED solvent sulfur removal was 20% higher than the TETRA and 10% higher than the PENTA solvents. As the solvent to feed ratio was increased, the sulfur removal rates were above 60 percent for all the solvents and the entrained hydrocarbon amounts ranged from 20 to 24 vol-%.
TABLE 2__________________________________________________________________________EXTRACTION OF FULL BOILING RANGE FCC GASOLINESulfur Content: 677 ppm-wt SINGLE WASH AT INDICATED VOLUME RATIO AVE 1:1 2:1 3:1SOLVENT T,°C. MW ppm HC % Sulf % ppm HC % Sulf % ppm HC % Sulf %__________________________________________________________________________TETRA 22 194 462 7% 36% 368 14% 53% 315 20% 63%PENTA 22 238 453 9% 39% 343 20% 59% 269 25% 70%MIXED 22 187 427 10% 43% 365 19% 56% 285 24% 68%__________________________________________________________________________
EXAMPLE III
A 100 gm sample of heavy FCC gasoline with an initial boiling point of about 160° C. (320° F.) and an end point the same as the full range gasoline of Example II and having a sulfur content of 2200 ppm-wt was mixed with 100 gm of TETRA at 100° C. according to the single-wash procedure of Example I. The single-wash extraction at a 1:1 solvent to feed ratio removed about 37 wt-% of the sulfur yielding 88 gms of raffinate with a sulfur content of 1602 ppm-wt and 12 gms of extract with a sulfur content of 6833 ppm-wt.
EXAMPLE IV
The procedure of Example II was repeated with 200 gms of TETRA at 100° C. to yield 71.8 gms of raffinate with a sulfur content of about 710 ppm-wt and 28.2 gms of extract with a sulfur content of about 5993 ppm-wt. This corresponds to about 77 wt-% sulfur removal based on the sulfur content of the extract at a solvent to feed ratio of 2:1.
EXAMPLE V
An engineering simulation of the process based on the single-wash data of Examples I and II for the present invention as shown in the Figure was developed for treating about 20,000 barrels per day (99.4 MKg/hr) of FCC gasoline. The total sulfur in the FCC gasoline is about 500 ppm wt, comprising mercaptans and thiophenes. The FCC gasoline stream is passed to a liquid-liquid extraction zone at a temperature of about 121° C. and a pressure of about 830 kPa. In the extraction zone, the FCC gasoline is contacted with tetraethylene glycol (TETRA) at a solvent to feed value ratio of about 2.2. A raffinate stream at a volumetric yield of 76 percent with a total sulfur content of about 111 ppm-wt is withdrawn from the stripping zone. The extract stream having a total sulfur content of about 1,620 ppm-wt is hydrotreated at mild conditions to remove essentially all of the sulfur from the extract and is recombined with the raffinate to provide a treated gasoline stream having a sulfur content of about 82 ppm-wt. Table 3 presents an overall material balance for Example V and indicates the percent removal of the components from the feedstream. Essentially all of the mercaptans and about 82.8 percent of the thiophenes in the feedstream are removed from the raffinate in the extraction step. In addition, about half or 53.6 percent of the aromatics are removed from the feedstream along with minor amounts of paraffins, olefins, and naphthenes. Because the aromatics in the extract were largely light (C 6 -C 8 ) aromatics such as benzene, toluene, and xylene, and the extract contained a minor portion (about 16.3%) of olefins, there is very little octane loss in the mild hydrotreating step. None of the octane of the light aromatics is lost at the mild hydrotreating conditions.
The energy consumption for the extraction process is about 150 MMkJ/hr of treated gasoline with approximately 77 percent of the energy supplied by low pressure saturated stream at 275 kPa pressure.
TABLE 3__________________________________________________________________________EXTRACTION OF SULFUR COMPOUNDSFROM FCC GASOLINE WITH 500 PPM SULFUR FCC GASOLINE RAFFINATE EXTRACT %COMPOUNDS WT % WT % WT % REMOVAL__________________________________________________________________________Paraffins 31.410 38.569 10.833 8.9Olefins 31.200 35.220 19.643 16.3Naphthenes 5.130 6.113 2.304 11.6Aromatics 32.090 20.062 66.664 53.6Mercaptans 0.016 -- 0.062 100.0Thiophenes 0.154 0.036 0.494 82.8TOTAL 100.00 100.00 100.00 25.8Flow Rates, MKg/hr 99.44 25.66Sulfur, ppm wt 500 111 1620 83.6Sulfur, ppm wt 82 73.78in Treated GasolineEXTRACTION CONDITIONSSolvent/Feed, Kg/Kg 3.2Solvent/Feed, Vol/Vol 2.2Temperature, °C. 49No. of Trays 60STRIPPING CONDITIONSTemperature, °C. 182Pressure, kPa 41No. of Trays 10ENERGY CONSUMPTIONMMkJ/hr 150 (142.2 MM BTU/hr)__________________________________________________________________________
EXAMPLE VI
In Example VI, a liquid extraction scheme is evaluated for the processing of an FCC gasoline stream having 1500 ppm wt sulfur compounds. The results are shown in Table 4. As in Example V, the FCC gasoline to be treated is passed to an extraction zone to provide a raffinate stream depleted in sulfur compounds containing about 130 ppm wt sulfur and an extract stream containing about 4052 ppm wt sulfur. After a mild hydrotreating step the extract stream and the raffinate are combined to provide the treated FCC gasoline stream with a total of 85 ppm wt sulfur. The energy requirement for processing the feedstream of Example V is about 212 MMkJ/hr, of which about 78% is supplied by saturated stream at about 275 kPa.
TABLE 4__________________________________________________________________________EXTRACTION OF SULFUR COMPOUNDS FROM FCC GASOLINEWITH 1500 PPM SULFUR FCC GASOLINE RAFFINATE EXTRACT %COMPOUNDS WT % WT % WT % REMOVAL__________________________________________________________________________Paraffins 31.410 42.232 11.243 12.5Olefins 31.200 36.932 20.518 23.0Naphthenes 5.130 6.580 2.428 16.5Aromatics 32.090 14.213 64.430 --Mercaptans 0.016 -- 0.139 100.0Thiophenes 0.154 0.043 1.242 94.0TOTAL 100.00 100.00 100.00 34.9Flow Rates, MKg/hr 99.44 64.72 34.72Sulfur, ppm wt 1500 130 4052 94.3Sulfur, in treated gasoline, 85EXTRACTION CONDITIONSSolvent/Feed, Kg/Kg 4.5Solvent/Feed, Vol/Vol 3.02Temperature, °C. 49No. of Trays 60STRIPPING CONDITIONSTemperature, °C. 182Pressure, kPa 41No. of Trays 10ENERGY CONSUMPTIONMM kJ/hr 212 (201.1 MM BTU/Hr)__________________________________________________________________________ | A process is disclosed for the removal of sulfur from petroleum fractions such as FCC gasoline by employing a solvent selected from the group consisting of a polyalkylene glycol, polyalkylene glycol ether, and mixtures thereof and having a molecular weight less than 400. The process is useful for saving energy, saving hydrogen consumption, and retaining octane. By requiring only the mild hydrotreatment of an extracted or absorbed stream concentrated with the sulfur impurities, the sulfur impurities are removed without the loss of octane resulting from conversion of either high octane olefins or aromatic components. In addition, the extract stream is a significantly smaller stream than the original feedstream. | 2 |
This is a continuation of co-pending application serial no. 756,210 filed on 7/18/85 now U.S. Pat. No. 4,725,099.
FIELD OF INVENTION
The present invention relates to a rotatable cutting bit of the type having an improved head portion and depending shank.
BACKGROUND OF INVENTION
Bits that are used in mining and for removing road surfaces are typically mounted in a machine having a power driven cutting wheel.
When employed on abusive material such as concrete, the attack bits encounter high pressures and undergo excessive steel wear around the tip section. Currently employed conically shaped tips not only experience degrees of blunting, thereby reducing machines speed, but also suffer from the presence of manufacturing flaws which can lead to total bit failure.
One example of commercially successful bits is described in U.S. Pat. No. 4,497,520, issued on Feb. 5, 1985 to Ojanen and assigned to the same assignee as the present invention. The patent discloses and claims a rotatable cutting bit where the head portion consists of a base section, a conical tip section with a maximum diameter, and an intermediate section contiguous with the base and tip sections. Under manufacturing conditions the dies used in forming these bits experience wear at the point of maximum tip diameter (the seam) resulting in unwanted accumulation of uncompressed carbide material (flashing). Commonly known methods of polishing, such as mechanical tumbling, remove the flashing but generate stress cracks along the same thereby increasing the likelihood of bit failure.
As a consequence of the commercial success of assignees Patent No. 4,497,520, consideration has now been given to improvements in construction relative to methods of manufacture for such tooling for better quality and control in production volumes.
SUMMARY OF THE INVENTION
In accordance with the present invention there is provided, a rotatable cutting bit comprising a head portion, a shank portion depending from said head portion along a longitudinal axis, said head portion having a socket at the forward end, a hard insert having coaxially aligned and integral sections, said sections comprising a base section, a tip section, a first intermediate section contiguous with said base, a second intermediate section of uniform diameter contiguous with said first intermediate and tip sections, said base being fixedly mounted in said socket and having a first diameter, said tip section being conically shaped and having a maximum second diameter, said first intermediate section having a maximum third diameter, said second intermediate section having a fourth diameter equal to said second diameter, said second and third diameters each being less than said first diameter, said first intermediate section at said base forming a fillet at the junction thereof whereby said base forms a shoulder with said first intermediate section.
The present invention alleviates the disadvantages of premature blunting and the formation of manufacturing flaws by providing a small diameter tip and by providing an adjoining cylindrical intermediate section. In production, the tip end plunger completes its compression stroke on a vertical section of the die rather than on the angular seam section of the prior art, thereby reducing die wear and the associated problems of flashing accumulation and stress crack formation.
DRAWINGS
FIG. 1 is a partially sectioned view of a bit mounted in block.
FIG. 2 is a side view of a tip;
FIG. 3 is an end view of a tip; and
FIG. 4 is a cut-out side view of the fillet section joining the first intermediate section and the base section.
DETAILED DESCRIPTION
Referring to the drawings, FIG. 1 shows a rotatable bit 11 having a head portion 13 and a depending shank portion 15 . The head portion 13 and shank 15 are coaxially aligned with the head 13 having an enlarged section 17 which prevents the head 13 from being forced into the opening in the mounting block 19 . The shank portion 15 which is a cylindrical configuration includes a sleeve 21 which is radially contracted when present in the opening so as to hold the bit 11 in the block 19 .
A hard insert 23 typically made of a carbide material is fixedly secured to the forward end of the head 13 . Preferably the base section 25 of the insert 23 is positioned in the socket and brazed in such a manner that the braze flows over and around the base section 25 .
In accordance with the principals of the present invention, the insert 23 includes a plurality of sections coaxially aligned with the head 13 and shank 15 of the bit 11 . The sections include a base section 25 , a tip section 27 , a first intermediate section 29 contiguous to both the base 25 and a second intermediate section 28 , and a tip section 27 contiguous with the second intermediate section 28 .
The tip section 27 tapers outwardly at an included angle “c” of from about 83 degrees to about 93 degrees. Preferably the angle is about 88 degrees. The point portion of the tip may be rounded to promote even wearing. Preferably the tip 27 extends downwardly in an axial direction toward the base 25 a distance of from about 0.12 to about 0.18 inches. The maximum diameter of the tip 27 is from about 0.36 to about 0.44 inches, and most preferably about 0.40 inches.
The second intermediate section 28 extends downwardly from the junction with tip 27 or forwardly from the junction with the first intermediate section 29 along a longitudinal direction a distance of about 0.02 to about 0.05 inches and most preferably about 0.03 inches. The second intermediate section 28 is cylindrical in shape and exhibits a uniform diameter equal to the maximum diameter of the tip 27 .
The first intermediate section 29 extends downwardly from the juncture with the second intermediate section 28 or forwardly from the juncture with the base 25 along a longitudinal direction a distance of about 0.22 to about 0.28 inches. Preferably the first intermediate section 29 has a frusto-conical shape and tapers outwardly to the base section 25 at an included angle “d” of from about 17 to about 23 degrees. The taper is outwardly from the junction with the second intermediate section 28 to the junction with the base 25 . The first intermediate section 29 has a maximum diameter less than the diameter of the base 25 .
The base section 25 preferably has a diameter of from about 0.60 to about 0.66 and most preferably about 0.63. The extension of the base 25 in the axial direction or the height of the base is from about 0.05 to about 0.11 inches preferably about 0.08. As illustrated in FIG. 3 and FIG. 4, a fillet 30 may be utilized to give a smooth transition from the base 25 to the first intermediate section 29 whereby the base 25 forms a shoulder with the first intermediate section 29 . The transition is in the form of an arc of radius between about 0.15 inches and about 0.25 inches which sweeps out a distance starting from the base section 25 forwardly to a diameter in the first intermediate section 24 of between about 0.54 to about 0.60 inches and preferably about 0.60. A more severe transition between the first intermediate section 29 and the base 25 often results in the formation of stress cracks along the fillet thereby increasing the likelihood of bit failure.
The total axial length of the hard insert is the sum of the axial lengths of the tip section ( 0 . 12 inches to 0 . 18 inches ) , the second intermediate section ( 0 . 02 inches to 0 . 05 inches ) ( which is a fifth distance ) , the first intermediate section ( 0 . 22 inches to 0 . 28 inches ) , and the base section ( 0 . 05 inches to 0 . 11 inches ) . It can this be seen that the axial length of the hard insert, which is a sixth distance, can range between 0 . 41 inches to 0 . 62 inches. Using the preferred dimensions, the axial length ranges between about 0 . 45 inches and about 0 . 57 inches.
The ratio of the fifth distance, which is the axial length of the second intermediate section, to the first diameter of the base section ranges between about 0 . 03 and about 0 . 08 . Based upon the preferred dimensions, this ratio of the fifth distance to the first diameter equals about 0 . 05 .
The ratio of the fifth distance ( the axial length of the second intermediate section ) to the sixth distance ( the overall axial length of the hard insert ) has a range between a minimum ratio and a maximum ratio. The minimum ratio is the ratio of the minimum fifth distance ( i.e., 0 . 02 inches ) to the maximum sixth distance that uses the minimum fifth distance. This sixth distance ( i.e., 0 . 59 inches ) used to arrive at the minimum ratio equals the sum of the maximum axial length of the tip section ( 0 . 18 inches ) , the minimum axial length of the second intermediate section ( 0 . 02 inches ) , the maximum axial length of the first intermediate section ( 0 . 28 inches ) , and the maximum axial length of the base section ( 0 . 11 inches ) . This minimum ratio equals about ( 0 . 02 / 0 . 59 ) 0 . 03 . The maximum ratio is the ratio of the maximum fifth distance to the minimum sixth distance that uses the maximum fifth distance. The sixth distance equals the sum of the minimum axial lengths of the tip section ( 0 . 12 inches ) , the first intermediate section ( 0 . 22 inches ) , and the base section ( 0 . 05 inches ) , and the maximum fifth distance ( 0 . 05 inches ) . This maximum ratio equals about ( 0 . 05 / 0 . 44 ) 0 . 11 . Based upon the preferred dimensions to the extent they are set forth, the preferred ratio of the fifth distance to the sixth distance ranges between about ( 0 . 03 / 0 . 57 ) 0 . 05 and about ( 0 . 03 / 0 . 45 ) 0 . 07 .
Since variations of this invention will be apparent to those skilled in the art, it is intended that this invention be limited only by the scope of the appended claims. | A rotatable cutting insert of improved geometry having a shank depending from a head portion and having a hard insert mounted therein, includes an insert having a conically shaped tip section, a base section contiguous with a first intermediate section, a second intermediate section contiguous with both tip and first intermediate section, and where the diameter of the second intermediate section is equal to the maximum diameter of the tip but is smaller than the diameter of the base section. | 4 |
FIELD OF THE INVENTION
Background of the Invention
The present invention relates to knitted therapeutic medical compression garments. More particularly, the present invention relates to knit therapeutic graduated compression stockings having courses of crimped bi-component yarns having an elastomeric core with a thermoplastic sheath and inlay courses containing spandex yarn.
Therapeutic medical compression stockings have been used on a relatively wide scale to assist in the prevention of venous diseases and/or embolism in a patient. The purpose of such stockings is to overcome the elevated internal pressures within a human extremity caused by gravity or disease processes.
The pressure gradient stocking and its use are well documented in the literature. The custom pressure gradient stocking was developed by Conrad Jobst a sufferer of venous disease. Mr. Jobst found relief from his problem while standing in a swimming pool. Mr. Jobst reasoned that the water pressure in the pool, which increases with depth, cancelled out the internal pressure in the veins of his leg. Jobst and others have identified a need to apply a relatively large compressive force in proximity to the ankle. See, page 535 of the article entitled “Conrad Jobst and the Development of Pressure Gradient Therapy for Venous Disease.” Also see, the article entitled “Treatment of venous disease—The innovators” at page 681 thereof quoting from an article by J. Horner, et al. entitled “Value of graduated compression stockings in deep venous insufficiency,” Br Med J. 1980; zz: 820-1 wherein it is stated “the greater the compression gradient between the ankle and calf produced by the stocking, the lower the ambulatory pressures.” Cited in U.S. Pat. No. 5,823,195.
Therapeutic medical graduated compression stockings are designed to provide sufficient external circumferential counter pressure to maintain the normal venous and lymphatic pressures at a given level in the extremity, thus assisting the movement of venous blood and lymph from the extremity. Another important effect of compression is the reduction of the venous volume. Reduction of venous volume leads to an increase of the venous flow velocity. Gerwen H J L van. Pressure gradient tolerance in compression hosiery . Katholike Universiteit Nijmegen. 1994, pp. 103-105.
Furthermore, while the exact mechanism(s) of action of gradient compression therapy remain unknown improvements in skin and subcutaneous tissue microcirculatory hemodynamics may contribute to the benefits of compression therapy. The direct effect of compression on subcutaneous pressure is a plausible mechanism. Edema reduction and edema prevention is the goal in patients with chronic venous insufficiency, lymphedema, and other edema causing conditions. Subcutaneous pressures increase with elastic compression. Nehler M R, Moneta G L, Woodard D M, et al. Perimalleolar subcutaneous pressure effects of elastic compression stockings. J Vasc Surg 1993;18(5):783-88. This rise in subcutaneous tissue pressure should act to counter transcapillary Starling forces, which favor leakage of fluid out of the capillary.
For instance, gradient compression stockings 20 mmHg and above have demonstrated the following effects in persons with venous insufficiency:
Improved venous hemodynamics
Prolonged (more normalized) venous refill time (VRT). Samson R H, Scher L A, Veith F J, et al. Compression stocking therapy for patients with chronic venous insufficiency. J Cardiovasc Surg 1985;26:10.
Reduced venous volume and increased venous flow velocity Reduction and control of edema. Dale W A. The Swollen Limb in Current Problems In Surgery , edited by Mark M Ravitch, et al. 1973 Year Book Medical Pub, Chicago. p. 29-31.
Most of the patients suffering from minor to moderate varicosities, moderate edema, superficial thronbophlebitis, and post sclerotherapy need to use stockings with the compression at ankle in the range from 15-20 to 20-30 mm Hg. More complicated and severe cases require pressure of 40 mm Hg and higher.
A variety of therapeutic medical graduated compression stockings are on the market today. The stockings of various descriptions have been proposed. Unfortunately, therapeutic stockings, in order to provide the necessary compression, are often thick and rather unsightly or have other drawbacks. An example of a therapeutic stocking is described in U.S. Pat. No. 3,975,929 which describes a thigh length anti-embolism stocking made with alternating courses of covered spandex yarn on a circular hosiery knitting machine. Another example of a therapeutic stocking is described in U.S. Pat. No. 4,069,515 to Swallow, et al., which discloses a non-slip therapeutic stocking having a covered elastomeric yarn (spandex core-nylon covering) inlaid into every other course of the jersey knit stitches made of stretch nylon. In particular, the Swallow patent describes the foot portion as having alternating courses of jersey knit stitches of non-elastomeric yarn. One of these yarns is a Z-twist stretch nylon and the other is an S-twist nylon. A covered elastomeric yarn such as a single covered elastomeric yarn having a 280 denier spandex core and covered with nylon 6 yarn is preferably inlaid into every other course of the jersey stitches.
The use of bi-component crimped yarns is known in the manufacture of pantyhose. Such garment construction is described in U.S. Pat. No. 5,352,518 to Muramoto, et al., who teach a stocking having a bi-component core and sheath type yarn wherein the sheath is composed of a fiber forming a thermoplastic polymer and the core is composed of a fiber forming elastomer. It is stated that the filament has excellent elastic properties, a small surface friction coefficient and a matting effect due to diffusion reflection of light caused by rough surfaces, and is agreeable when worn in the form of a knitted textile structure, particularly as a lady's stocking.
SUMMARY OF THE INVENTION
A principle feature of the present invention is the provision of a therapeutic medical compression stocking made with bi-component fibers. It has been found that the use of bi-component yarns, in particular, those crimped yarns having an elastomeric core and a thermoplastic sheath when knit with inlaid courses of spandex or spandex covered with a bi-component yarn form therapeutic stockings that provide excellent compression control. In addition, these therapeutic stockings are more transparent than conventional therapeutic stockings. The therapeutic stockings of the present invention may be knit on a conventional circular knitting machine.
In a first preferred embodiment every course of the therapeutic stocking is knit with a crimped bi-component yarn having an elastomeric core and a thermoplastic sheath. Courses of an inlay yarn of spandex are provided at least every third course. In a second embodiment, the therapeutic stocking is knit with every other course being the crimped bi-component yarn and the inlay yarn is spandex present in every course. The alternate courses are covered spandex yarn. It was found that the use of spandex yarns in combination with the bi-component yarn enables the reduction in size of the spandex used in the inlay courses and maintains the desired compression.
In yet another embodiment of the present invention, there is provided a knitted therapeutic stocking comprising a crimped bi-component yarn in every course and an inlay yarn of spandex covered with a bi-component yarn. In a fourth embodiment there is provided a knitted therapeutic stocking comprising a crimped bi-component yarn in every other course and inlay course of spandex covered with a bi-component yarn.
It has been found that the therapeutic medical compression stockings of this invention provide a smooth, silky, cool and supple hand of fabric; easier donning, lighter weight, good durability and very good compliance with patient needs.
It is an object of the present invention to provide a therapeutic stocking having excellent compression by using an improved bi-component crimped yarn of the present invention.
Another object of the present invention is to provide an improved air-permeable therapeutic stocking because the spandex inlay yarns do not need to be covered.
Yet another object of the present invention is to provide a therapeutic stocking having improved transparency.
Other features and advantages of the present invention will become apparent in the following detailed description of the embodiments of the invention when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Having thus described the invention in general terms, reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein:
FIG. 1 is an isometric view of a therapeutic stocking of the present invention;
FIG. 2 shows a bi-component, uncrimped yarn used to knit the therapeutic stockings of the present invention illustrating;
FIG. 3 shows the bi-component yarn of FIG. 2 used to make the therapeutic stockings of this invention in its crimped condition;
FIG. 4 is a photomicrograph of a fragmentary portion of a fabric made of bi-component yarns showing a first embodiment of a knit fabric used to make the therapeutic stocking of the present invention taken in the area of rectangle A in FIG. 1;
FIG. 5 is a photomicrograph of a fragmentary portion of a fabric made of bi-component yarns showing a second embodiment of a knit fabric used to make the therapeutic stocking of the present invention taken in the area of rectangle A in FIG. 1;
FIG. 6 is an enlarged view of a fragmentary portion of a fabric made of bi-component yarns showing a third embodiment of a knit fabric used to make the therapeutic stocking of the present invention taken in the area of rectangle A in FIG. 1;
FIG. 7 is an enlarged view of a fragmentary portion of a knit fabric made of bi-component yarns showing a fourth embodiment of the fabric used to make the therapeutic stocking of the present invention taken in the area of rectangle A in FIG. 1;
FIG. 8A shows a spandex yarn covered with a double bi-component yarn used in the inlay courses of the therapeutic stockings of the fourth embodiment of the present invention; and
FIG. 8B shows a spandex yarn covered with a single covering of bi-component yarn used in the inlay courses of the therapeutic stockings of the fourth embodiment of the present invention.
FIG. 9A shows a spandex yarn core covered with two bi-component yarns used in the inlay courses of the therapeutic stockings of an embodiment of the present invention.
FIG. 9B, shows an embodiment of the inlay yarn having a spandex core covered with a single layer of bi-component yarn used in the inlay courses of the therapeutic stockings of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention now will be described more fully hereinafter with reference to the accompanying drawings, in which preferred 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.
There is shown in FIG. 1 the therapeutic medical compression stocking 10 of the present invention. The stocking 10 includes a leg portion having an enlarged upper section 11 and a foot portion 12 . The foot portion 12 including a heel pocket 13 and a toe pocket 14 . The upper section 11 of the medical stocking can be provided with an upstanding and integrally knit band 15 for knee length or thigh length stockings, or a sewn in anti-slip band. Alternatively, the stockings can be an integral part of a panty hose garment.
An example of a bi-component yarn used to make the therapeutic medical compression stockings is shown in FIG. 2 . The yarn 20 is composed of an elastomeric core 21 , that is preferably a polyurethane, more preferably a cross-linked polyurethane. Any of such known polyurethane as polycarbonate-urethanes, polyactone-urethanes and polyether-urethanes may be used as the polymer that forms the polyurethane core in the form of a homopolymer or copolymer of polyurethane or a mixture thereof. As a yarn forming thermoplastic polymer forming the sheath 22 of the yarn a polyamide such as nylon 6, nylon 66, or nylon 12 is preferred. Additionally, polyolefins also can be suitably employed. The core/sheath bi-component weight ratio is in the range between 20:80 and 80:20, with 50:50 by weight especially preferred. The core/sheath bi-component ratio is preferably within the range between 5/1 and 90/1, more preferably between 10/1 and 50/1, by cross-sectional area. Especially preferred are those polyurethane yarns disclosed in U.S. Pat. No. 5,164,262, incorporated herein by reference.
Additionally, the bi-component yarn may have an eccentric configuration such as those yarns disclosed in U.S. Pat. No. 5,352,518. The use of eccentric yarns allows the attainment of latent crimping properties that allow coil-like crimps to be produced by the crimp development treatment. An illustration of a bi-component yarn in crimped configuration is shown in FIG. 3 wherein the crimped yarn 30 has an elastomeric core 31 and a polyamide sheath 32 . The bi-component yarns used to make the therapeutic stocking of this invention may be self-crimping yarns that form crimps, including helical coil-like crimps spontaneously. The yarns may also be externally treated such as by using an elevated temperature, or a swelling agent. Such bi-component yarns are commercially available under the name Sideria® available from Kanebo of Japan.
The elastomeric yarn used in the alternating or inlay courses is preferably spandex, such as Globe's Clearspan® manufactured by Globe Manufacturing Inc., Fall River, Mass. Other spandex yarns that may be used includes Lycra® spandex manufactured by DuPont, or Dorlastan® spandex manufactured by Bayer, or any other applicable spandex yarn. In some embodiments of the invention the spandex yarn is covered with a bi-component yarn such as described above or with nylon yarns as shown in FIG. 8 A and FIG. 8 B. In some embodiments of the invention the spandex yarn can be covered with one (so-called single covered as shown in FIG. 8A) or two layers (double covered as shown in FIG. 8B) of nylon or bi-component yarn.
The fragmentary view A of a portion of fabric structure in the leg section 11 of the stocking (FIG. 4) is illustrates a first preferred embodiment of the therapeutic stocking of this invention as if the fabric were stretched in both coursewise and walewise directions. As shown in FIG. 4, each course (C- 40 , C- 42 , C- 44 , C- 46 and C- 48 ) of the therapeutic stocking is knit with a crimped bi-component yarn. Courses (C- 41 , C- 43 , C- 45 , C- 47 and C- 49 ) of inlay yarn are spandex. Courses of inlay yarn are laid in at least every three courses. It should be understood, however, that if more compression is needed the inlay courses may be used more frequently as shown by inlay yarns in every course in FIG. 4 . It was found that the combination of bi-component yarns and spandex enabled the reduction in size of the spandex core used in the inlay courses and maintain the desired compression.
As shown in the second embodiment, that of FIG. 5 illustrating a fragmentary view A if a portion of fabric structure in the leg section 11 of the stocking, the therapeutic stocking is knit with alternating rows of jersey knit stitches of crimped bi-component polyurethane yarn. The intervening rows are courses of covered elastic yarn. A covered elastic yarn is a single covered elastic yarn, such as spandex with a covering yarn singly or double wound around the elastic yarn. Any polyamides such as nylon 6 and nylon 66, which are used for common polyamide fibers, can be used as the material of the polyamide filaments constituting the covering yarn. As shown in FIG. 5, every other course (C- 50 , C- 53 , and C- 56 ) of the therapeutic stocking is knit with a crimped bi-component yarn. The intervening courses (C- 52 , C- 55 and C- 58 ) are of covered elastic yarn. Courses (C- 51 , C- 54 and C- 57 ) of inlay yarn are spandex.
In FIG. 6 there is shown a third embodiment of the fabric structure A in the leg section 11 of FIG. 1 used to knit the therapeutic stockings of the present invention. In this embodiment every course (C- 60 , C- 61 , C- 63 , C- 64 and C- 66 ) of the knit stocking is a bi-component yarn. Each course of inlay yarn (C- 61 and C- 65 ) is comprised of spandex covered with a bi-component yarn. Such construction enables the reduction in the size of spandex in each course.
There is shown in FIG. 7 a fourth embodiment of the fabric structure A used to knit the therapeutic stockings of the present invention. As shown in FIG. 7, every other course (C- 70 , C- 73 and C- 76 ) of the therapeutic stocking is knit with a crimped bi-component yarn. The intervening course (C- 72 and C- 74 ) are of covered elastic yarn. Courses (C- 71 and C- 75 ) of inlay yarn are spandex covered with a bi-component yarn. Preferred yarns are shown in FIG. 8 A and FIB. 8 B.
In FIG. 9A there is shown a spandex yarn core covered with two bi-component yarns used in the inlay courses of the therapeutic stockings of the fourth embodiment of the present invention. As shown in FIG. 9A, the yarn 80 has a spandex yarn component 81 . The spandex yarn is covered with one layer of bi-component yarn 82 wound in one direction and then a second bi-component yarn 83 wound in the other direction. In FIG. 9B, there is also shown another embodiment of the inlay yarn 85 having a spandex core 86 covered with a single layer of bi-component yarn used in the inlay courses of the therapeutic stockings of the fourth embodiment of the present invention.
EXAMPLE 1
A therapeutic stocking was knit with a jersey knit structure on a conventional circular knit hosiery machine. The leg yarn was a crimped bi-component yarn having a polyurethane core with a polyamide sheath in each course as shown by the fabric structure of FIG. 4 . The inlay yarn was bare spandex. This stocking was then compared to the stocking presently on the market. The result is shown in Table 1.
TABLE 1
Property
Prior Art 1
Invention
Knit structure
Jersey with bare spandex inlay
Jersey with bare spandex
inlay
Leg yarn
Covered, polyurethane core
Bi-component,
and polyamide over wrap
polyurethane core with
polyamide sheath 2
Total (Sum) linear density
50
50
of leg yarn
Denier (Linear Density)
20
25
Weight of polyurethanecore
part (yarn)
Denier (Linear Density) of
30
25
cover part (yarn)
(double covering with 15 den
(sheath)
nylon)
Linear density of inlay yarn
105 den polyurethane yarn 4
70 den polyurethane
yarn 3
Total linear density of
125
95
polyurethane yarns
Pressure at ankle
18.5
21.6
Donning force at ankle, kg 5
3.3
2.5
Weight, g, one leg size
26
17.8
medium
Suppleness/stiffness -
Less supple
Very supple. Not stiff.
expert evaluation
Thin
Hand
Not silky, feels harsher than
Smooth, silky, cool, not
prototype, slightly rubbery
rubbery
especially inside a stocking
Air permeability, ASTM-
730
876
737 cm 3 /s/cm 2
1 Jobst UltraSheer 15-20 medical hosiery.
2 Sideria yarn from Kanebo.
3 162C Lycra from DuPont.
4 S85 Glospan from Globe Manufacturing Co.
5 These measurements were taken according to the test set forth in PCT/U.S.99/21676 filed September 17, 1999.
EXAMPLE 2
To further demonstrate advantages in donning, and fabric's air-permeability and suppleness the stockings were knitted from bi-component and conventionally covered yarns. Yarns of similar deniers were used and conditions of knitting were adjusted to produce stockings with similar pressure values.
TABLE 2
Property
Prior Art 1
Invention
Knit structure
Jersey with bare spandex
Jersey with bare
inlay
spandex inlay
Leg Yarn
20 den Lycra double
Bi-component
covered with 20 den nylon
Total leg yarn denier
60
50
Denier of inlay yarn
140
140
Total linear density of
160
165
polyurethane yarns
Pressure at ankle
25.1
23.9
Donning force at ankle,
3.7
2.3
kg
Air-permeability
598
746
Stiffness, g, ASTM
18.5
9.2
1 Jobst UltraSheer 20-30 medical hosiery.
Again it can be easily seen that use of bi-component yarn results in significant improvements in stocking's donning, and fabric's air-permeability and suppleness.
As can be seen from the results obtained, the first embodiment provides a therapeutic stocking that has superior properties, which is very supple and has a smooth silky cool hand.
Many modifications and other embodiments of the invention will come to mind to one skilled in the art to which this invention pertains having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the invention is not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation. | A knitted therapeutic medical compression stocking made from courses of bi-component fibers inlaid courses of spandex yarn. The use of bi-component yarns, in particular, crimped yarns having an elastomeric core preferably of a polyurethane and a thermoplastic sheath preferably of a polyamide when knit with inlaid courses of bare spandex, covered spandex, or spandex covered with a bi-component yarn forms therapeutic medical stockings that provide excellent compression control. In addition, these therapeutic stockings are more transparent than conventional therapeutic stockings. The therapeutic stockings of the present invention may be knit on a conventional circular hosiery knitting machine. | 3 |
BACKGROUND OF THE INVENTION
The present invention relates to a novel intermittent continuous method and device for recovering refined activated carbon from waste tyres and the like and, in particular, to a treatment process to for producing effectively by refining activated carbon with a high added value from waste rubbers such as waste tyres, through an intermittent continuous process of treatments without formation of a secondary public nuisance while the oil-gas produced thereby as a by-product being recovered and used as a source for outer heating in the splitting decomposition and activation thus achieving a recovery of resources, and to a device for use in this process.
Owing to the development in public roads and the popularity of cars and motorcycles, the number in the growth of waste tyres of consummable materials has increased greatly and has been a problem for an immediate resolution on environmental protection.
For solving this problem on waste tyres, generally, three methods have been adopted, these are: burial, incineration and pyrolysis. By burial, the waste tyres are discarded and buried as general garbage and are not regenerated. It is therefore a waste of resources and the method will not be discussed here. As according to the incineration method, the waste tyres are pulverized and the weight (volume) is reduced to become fuel for combustion, mainly for use in burning the specially made boiler to recover the thermal energy thereof to warm houses water, etc. However, because such a method is of a direct combustion, the costs in the treatment of secondary public nuisance on removal of smoke, stink, burned ash and separation of steel wire and in the equipment have become another problem. As regards the splitting decomposition (dry distillation), waste tyres are pulverized and then thrown into a sealed splitting decomposition furnace where the pulverized waste tyres are subject to a high temperature heat splitting decomposition and dry distillation and the gases that are produced by decomposition are then cooled, separated and absorbed to obtain the fuel oil, fuel gas, carbonized substance and steel wire residues while the fuel oil and gas are for general use and part of which can be recovered for use in a thermal decomposition furnace, the ash residues have to be separately buried or magnetically separated to separate out the iron wire with the remaining carbonized substance after pulverization and granulation to produce low grade carbon black for use as packings in the tyre manufacture. Although such a process can have a considerable result in the recovery of resources for reuse and can also reduce the problem of secondary public nuisance in smoke elimination, equipments and the processing system are far from being ideal and the process works by batch only. Operation can be disintegrated and not continuous, and the procedures can be redundant and can result in the wastage of energy resources. The method is much in need for improvement.
Japanese Patent Application No. Showa 58-25384 discloses a method and device whereby waste tyres are thrown directly into an incinerator for combustion, and the gases formed are led out from a smoke outlet. The carbonized substances are recovered via a pipeline while on the other hand, the melted fluid is recovered from the bottom of the incinerator as fuel. This direct and open type incineration method results, however, in the secondary public nuisance of stinking smell and black smoke.
On the other hand, U.S. Pat. No. 5,326,791 teaches a process of splitting decomposition and oil treatment of thermoplastic high molecular compounds and heating hydraulic separation of non-hydrolyzable waste plastics.
However, none of the above cited prior references is involved in the process or system for recovering activated carbon from rubber of any waste tyres or discloses a precise device for possibly recovering activated carbon from the waste tyres; still further, no suggestion has been made that would affect improved method or device in batch splitting decomposition manner for processing the production energy.
SUMMARY OF THE INVENTION
Accordingly, a major object of the present invention is to provide a method for the recovery treatment of waste tyres and the like, whereby waste tyres are thrown into a specially made sealed splitting decomposition furnace of the processing system and through an intermittent and continuous integrated treatment to extract activated carbon and also to obtain by-products of the combustible oil-gas to be used for heating by the system to thereby raise considerably the processing production energy while at the same time lowering the processing cost.
A further object of the present invention is to provide a recovery processing device for waste tyres and the like, where it is capable of intermittently and continuously processing the waste tyres without having to shut down the furnace or to hang it up for cleaning or to replace the tank in the splitting decomposition furnace, and the final product obtained is the activated carbon with a high added value.
A still further object of the present invention is to provide a waste tyre recovery processing system capable of recovering almost all of the waste tyres and returning them into resources thereby solving the problem on environmental protection.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of a preferred embodiment of the invention, as illustrated in the accompanying drawings.
FIG. 1 shown a flowchart of the waste tyre recovery processing system of the invention; and
FIG. 2 shows a longitudinal sectional view of the splitting decomposition furnace of the the invention.
DETAILED DESCRIPTION OF THE INVENTION
With reference to FIGS. 1 and 2, the intermittent and continuous processing system for waste tyres and the like, in accordance with the present invention, will be described in detail as follows.
T denotes waste tyres, 1, conveyer belt and 2, pulverizer, and the waste tyres T are transported via the conveyer belt 1 to pulverizer 2 where they are pulverized into sizes below 5 cm (the smaller the cm the better will be the sizes). The pulverized waste tyres are then transported by a conveyer 3 into a feed tank 4, at the outlet end of the feed tank 4 is disposed a continuous intermittent type pulverized pieces automatic metering and throw-in device 5 for throwing the pulverized waste tyres each time at a determined amount into a splitting decomposition reactor 6. This reactor 6 comprises a double-bottom reaction tank 61 for splitting dry distillation and a closed furnace body 62 encircling the reactor tank 61 for heating the tank. The reaction tank 61 is provided on the inside with an agitator 63, which will be dealt with in detail later.
In the reaction tank 61, the pulverized pieces are gasified after heating and splitting decomposition. The temperature inside the reaction tank 61 is maintained always at 400° C. to 600° C., preferably between 450° C. to 550° C., while the pressure is kept under a pressure of 1.0 to 2.5 kg/cm 2 . From an outlet at the upper end of the reaction tank 61 the oil-gas MG produced in the gasification is led through a conduct pipe L1 into a condenser 7 where it is cooled to below 50° C. or room temperature and is then passed into an oil-gas separating tank 8. The combustible fluid when condensed, that is, the fuel oil F, is deposited on the bottom of a separating tank 8, and is next forced by a pump 9 to flow through a conduct pipe L2 to an oil storage tank 10 for storage. The non-condensing gases, that is, fuel gas G, is compressed by a compressor 11 and, after passing through a conduct pipe L3 and having impurities and odors absorbed at an absorption tank 12, is then stored in a gas storage tank 13. The fuel oil F and the fuel gas G, thus obtained, are led respectively by conduct pipes L4 and L5 into combustors 64 mounted on the furnace body 62 of the splitting decomposition reactor 6 for combustion in order to heat the reaction tank 61 and the fuel oil F and fuel gas G that are left unused can be supplied to other equipments in the factory or neighboring houses as fuel. Thus, any thermal energy needed for operating the reactor 6 can be supplied from the recovered oil-gas and this can result in a saving of energy resources. On the other hand, if electric heating method is used for heating by the reactor 6, the fuel oil and gas may then be utilized as reserve fuel during power failure.
By analysis, the non-condensing fuel gases are mostly found to be methane and ethane, which having stored in the gas storage tank 13 can be re-used or sold out. On the other hand, the fuel oil can be used as heavy oil in combustion or, if it is necessary for further refining, the fuel oil can be refined into light oil and heavy oil by passing separately through refining equipment of filtering and fractional distillation apparatuses (not shown).
On the other hand, the mainly solid carbonized substances left over in the bottom of the reaction tank 61, namely, the carbon black C, upon reaching a determined amount, are discharged through the upper and lower double cone bottom parts 65 and 66 into the inlet of a screw conveyer 14 at the bottom of the furnace and are again discharged through an outlet feed discharge pipe 14a into a carbon black cooling water tank 15 for cooling. Midway of the feed discharge pipe 14a is located an obstruction part 14b passed with an inert gas such as: nitrogen, which together with a water-sealed portion formed by the cooling water tank 15 constitutes a double-seal action to block the gas, produced as a result of high temperature and low pressure in the reaction tank 61, from joining together with the atmosphere thereby ensuring a double safety.
The cooled carbonized substances C are delivered by a conveyer belting 19 to a magnetic separator 16, where the steel wire S contained in the carbonized substances is adsorbed, separated and next sent into a steel wire tank 17. The carbonized substances C, after having the steel wire S separated out, are then delivered in sequence by means of acid-alkali resistant conveyer beltings or any other suitable devices 19a, 19b into an alkali bath 18 and an acidic bath 20 where, the substances C are alkaline-cleaned and acidic-pickled to remove the ash content or impurities containing ZnS, ZnO, FeS, Fe 2 O 3 and CaS, which are soluble in acid, and SiO 2 which are soluble in alkali. Thereafter, the substances C are sent to a water washing bath 21 for washing with water so as to obtain a pure and clean carbon black C. This carbon black is again sent by a conveyer belting 19c into a drying stove 22 in which it is dried. The dried carbon black is then collected in a feed tank 23 and is next sent into a fine grinding machine 24 to be ground into fine powdered carbon C1 of 100 to 200 mesh. Thereafter, the powdered carbon is delivered to a cyclone separator 26 and is separated there to obtain fine carbon powders. The carbon powders are next sent into an activation furnace 25 for activation at a passage of steam and a temperature maintained at above 700° C. The product thus obtained is the activated carbon 9 with a very high degree of purity. Precisely, the fine carbon powder C1 is delivered through a charging hopper 251 into a reaction chamber 252 of the activation furnace 25, the temperature in the reaction chamber 252 is maintained at above 700° C., preferably at 800° C. to 900° C., and into which is also passed air and steam separately, through a steam inlet a and an air inlet b. In the reaction chamber 252, the fine carbon powder C1 is subject to contact with the high temperature and steam and the activation reaction to form activated carbon, which is next sent through a conduct pipe 253 by an airflow into an activated carbon collecting chamber 254 and is again gathered in a collecting barrel 255. As to the waste gases, they are expelled out through an air outlet 256. Furthermore, the numerical reference 257 denotes a normally closed opening for sweeping use.
A detailed construction of the one embodiment of the splitting decomposition reactor 6 utilized in this invention is as shown in FIG. 2, in which the reactor 6 comprises a cylindrical reaction tank 61 and a large-diameter cylindrical furnace body 62 encircling on the outer circumference of the reactor 6. On the circumferential wall of the furnace body 62 is located a plurality of combustors 64 for uniformly heating the interior of the furnace body 62 from upper to lower on all sides thereof. The interior of the reaction tank b1 is provided with an agitator 63 with the upper end supported by an upper cover 67. This agitator 63 has large-and-small size agitating vanes 632, 633 arranged one above the other on a shaft 631 and is capable of performing reciprocating agitating movement in an up and down manner. Thus, when the cylinder 634 is driven, the agitator 63 moves up and down and brings the solid materials inside the reaction tank b1 into an up and down agitating movement so that the solid materials, that have been thrown into the reactor, are exposed to an atmosphere of high-temperature heat. While the materials are sufficiently and evenly heated, at the same time the carbonized substances, that have attached to the inner wall of the tank, are scraped, so that materials can be heated and decomposed in a relatively short time where it helps raise the efficiency of thermal decomposition. The outer wall of the reaction tank 61 is preferably provided with a screw heat absorbing sheet in order to increase the heating area and save energy resources by allowing the flame stagnant time to be extended. The bottom of the reaction tank 61 is formed into an upper and a lower double cone bottom parts 65, 66, an outlet 651 on the bottom of the upper bottom part 65 is closed by a discharge port lower cover 681 of the air cylinder 68 disposed on the outer part of the lower bottom part 66 and capable of opening and closing by extending action. Again, the bottom of the lower bottom part 66 is formed into a feed outlet 661 passing to the inlet of the screw conveyer 14 driven by a motor M. When the air cylinder 68 moves into action and the lower cover 681 is opened with pivot on one end by means of its own body weight, the carbonized substances that have stored up in the reaction tank 61 fall into the lower bottom part 66 by the own body weight thereof and the up and down velocity pressure of the agitator 63 and from the feed outlet 661 the substances enter the screw conveyer 14. When discharge of the carbonized substances is finished, the air cylinder 68 is started again and pushes the lower cover 681 upwardly to cover the outlet 651 tightly. In order to allow the pulverized materials to enter the reaction tank 61 and thereafter to be dispersedly scattered in the tank, the feeding hole of the tank is preferably equipped at the lower part with a dispersion plate 612.
The high-temperature air exhaust on the furnace body 62 of the reactor 6 can be led by conduct pipe L0 and dispenser 69 to the lower portion of the upper bottom part 65 and the drying room or to any other devices where a heat resource is required, for re-use.
Owing to special design of the reactor 6, the materials, which have been thrown into the reactor, are dispersed and fall down scatteringly, and by up and down agitating movement of the agitator 63 in the reaction tank 61 the materials appear to be in a floating and scattering states. This, while reducing the speed in the fall-down, extends also the contacting time with the hot air whereby the surface area of the materials appears to be in maximum limit of an effective heating surface and because the tank bottom 65 is provided with many heat transfer sheets 621 to absorb the exhaust heat content coming from the dispenser 69, the materials on reaching the tank bottom 65 thus possess a good heat transfer effect. Hence, the entire reaction process can be finished within a short time.
The splitting decomposition reaction is an endothermic reaction and in the conventional batchwise large-volume filling-type reaction, a very large quantity of heat is needed so as to adequately supply the quantity of heat required in the reaction. Nevertheless, according to the present invention, the materials are thrown into the reaction tank in small scale each time in an intermittent and continuous manner and thus a large quantity of heat is not required. Furthermore, since according to the present invention the reaction proceeds at a state of up and down agitating motion, it is thus possible to finish the reaction in a very short period and depending on the composition of the materials and the size of the pulverized particles, the time may generally be from 30 to 50 min., which will and also help in a saving of heat energy.
During the alkaline cleaning of the carbonized substances, 2% to 3.5% NaOH solution is preferably used, whereas in the acid pickling (treatment) 7% to 15% HCl solution is generally preferred. After the alkaline cleaning and the acid pickling, the ash content of the carbonized substances may fall to below 3%. Because by the alkaline cleaning only SiO is dissolved and the majority of the ash content will not dissolve in alkali but is dissoluble in acids, therefore, from an economical point of view the alkaline cleaning step may be omitted if necessary, and the acid treatment only is to be followed.
After a treatment in accordance with the method of the present invention of a mixture of waste tyres of different brands, the following contents are obtained, in which the fuel gas is about 10% to 12%, the fuel oil, about 25% to 30%, the activated carbon, about 50% to 55% , the steel wire, 10% to 12% and the others, about 5% to 9%.
Again, according to the steam activation method of the present invention, the activation process may be completed within a short time of a few minutes and the purified carbon black is activated at two types of temperature of 800° C. and 900° C., respectively, to obtain the activated carbon, the property of which is as follows (Table 1).
TABLE 1______________________________________Activation Temperature 800° C. 900° C.______________________________________Recovery Rate (%) 85.8 82.2 Adsorptive Capacity 32.7 35.2 Methylbenzene g/g Activated Carbon BET Surface Area 627 852 (m.sup.2 /g) Single-point Surface 619 843 Area (m.sup.2 /g)______________________________________
It is to be appreicated that the pulverized pieces of waste tyres from the upper part of the reaction tank 61 are metered and thrown into the device intermittently and by the external heat under agitation in the reaction tank 6, the pulverized pieces perform the intermittent and continuous splitting decomposition reaction to produce oil-gas and the carbonized substances. The oil-gas after cooling and separating forms the fuel gas and the fuel oil for use by the reactor and in addition to that, the carbonized substances that have accumulated in the tank are expelled out intermittently. The substances, after absorption of steel wire by the magnetic separator and subject to the alkaline and acid treatments to first remove the ash content and next subject to purification, are activated by steam to form the activated carbon. This process, under the most effective system, has achieved the effectiveness in completely reducing the amount of waste tyres and in the recovery of resources.
DESCRIPTION OF REFERENCE NUMERALS
______________________________________T waste tyres 18 alkaline cleaning 1 conveyer belt 19 conveyer belting 3 conveyer 20 acid pickling bath 4 feed tank 21 water washing 5 automatic metering device 22 drying stove 6 reactor 23 feed tank 61 reaction tank 24 grinding machine 62 furnace body 25 activation furnace 63 agitator 251 hopper 64 combustor 252 reaction chamber 65 upper bottom part 254 activated carbon collecting chamber 66 lower bottom part 255 collecting barrel 67 upper cover 2 pulverizer 7 condenser 26 cyclone separator 8 oil-gas separating tank 611 heating absorbing sheet 9 pump 612 dispersion plate 10 oil storage tank 68 air cylinder 11 compressor 681 lower cover 12 absorption tank 69 dispenser 13 gas storage tank 14 screw conveyer 15 cooling water tank 16 magnetic separator 17 steel wire tank______________________________________ | A method and device is provided which is capable of producing gasified substance and solid-shaped carbonized substances from solid-shaped wastes such as waste tyres by a series of heating, dry distillation and splitting decomposition. After discharging out from the bottom of a splitting decomposition reactor, the solid-shaped carbonized substances are subject to a series of treatments: water washing, magnetic separating, alkaline cleaning and acid pickling (treatment) to separate out iron wire and to remove heavy metal-bearing ash contents. The carbonized substances are next pulverized to the desired particle size so that highly purified carbon black is formed. Subsequently, the carbon black granules are led into an activation furnace and are heated and activated at the atmosphere of steam being passed in to produce powder particulate activated carbon. On the other hand, from the gasified substance produced by-products of the combustible oil and gas are respectively formed. This combustible oil and/or combustible gas can be led into the splitting decomposition reactor and the activation furnace as fuels for heating on the outside of the furnace and where the remaining portion of which may be sold to the outside. The above process of treatments is accomplished at an intermittent and continuous way and recovery rate of the activated carbon is high whereas the treatment time is shortened. | 2 |
This application is a DIV of Ser. No. 08/659,636 Jun. 6, 1996 ABN which is a DIV of Ser. No. 08/351,140 Nov. 30, 1994 U.S. Pat. No. 5,650,013 which is a CON of Ser. No. 08/064,212 May 12, 1993 ABN which is a DIV of Ser. No. 07/842,758 Feb. 28, 1992 ABN which is a CON of Ser. No. 07/595,762 Oct. 3, 1990 ABN which is a CON of Ser. No. 07/312,420 Feb. 21, 1989 ABN which is a CON of Ser. No. 07/092,130 Sep. 2, 1987 ABN which is a DIV of Ser. No. 06/801,768 Nov. 26, 1985 ABN.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a layer member forming method which is suitable for use in the fabrication of various electronic devices of the type having an insulating, protecting, conductive, semiconductor or like layer member formed on a substrate member.
2. Description of the Prior Art
Heretofore there has proposed a method for forming such a layer member on a substrate member through use of a photo CVD or plasma CVD process.
According to the method utilizing the photo CVD technique, the substrate is placed in a reaction chamber provided with a light transparent window and a reactive gas mixture, which contains at least a gas of a material for the formation of the layer member desired to obtain, is introduced into the reaction chamber. Then light is introduced into the reaction chamber through the light transparent window thereof by which the reactive gas mixture introduced thereinto is excited for vapor-phase decomposition and the material for the layer is deposited on the substrate member.
With the method utilizing the plasma CVD technique, the substrate is placed in a reaction chamber and a reactive gas mixture, which contains a gas of a material for the formation of the layer, is introduced into the reaction chamber. In the reaction chamber the reactive gas mixture is excited into a plasma by grow discharge or electron cyclotron resonance for vapor-phase decomposition by high frequency electric power so that the material for the layer is deposited on the substrate.
With the photo CVD process, since the material gas resulting from the vapor-phase decomposition of the photo-excited reactive gas is not accelerated, it is possible to form the layer on the substrate with substantially no damage inflicted on the substrate surface. On this account the layer can easily be formed without containing the material forming the substrate surface or without introducing into the substrate surface the material forming the layer, without developing any undesirable interface level between the layer and the substrate and without applying any internal stress to the layer and the substrate. Furthermore, since the photo-excited material gas has a characteristic to spread on the surface of the substrate member, the layer can be deposited in close contact with the substrate even if the substrate surface is uneven.
Accordingly, the use of the photo CVD technique permits easy formation of the layer of desired characteristics, without causing any damages to the substrate surface, even if the substrate has an uneven surface.
With the photo CVD process, however, since the photo-excited material gas is not accelerated toward the substrate, the deposition rate of the layer is lower than in the case of employing the plasma CVD technique. Therefore, the photo CVD process takes much time for forming the layer as compared with the plasma CVD process. Furthermore, the material for the layer is deposited as well on the light transparent window during the formation of the layer, causing a decrease in the light transmittivity of the window as the deposition proceeds. Therefore, the layer cannot be formed to a large thickness. For instance, in the case of forming a silicon nitride layer, it is difficult, in practice, to deposit the layer to a thickness greater than 1000 A. Moreover, difficulties are encountered in forming a silicon layer to a thickness greater than 200 A, a silicon oxide (SiO 2 ), or aluminum nitride (AlN) layer to a thickness greater than 3000 A, a silicon carbide (Si xC 1-x , where 0<x<1) layer to a thickness greater than 500 A and a germanium silicide (Si x Ge 1-x , where 0<x <1) or metal silicide (SiM x , where M is metal such as Mo, W, In, Cr, Sn Ga or the like and 0<X≦4) layer to a thickness greater than 100 to 200 A.
with the plasma CVD process, since the material gas resulting from the vapor decomposition of the reactive gas excited by electric power can be accelerated toward the substrate, the deposition rate of the layer is higher than in the case of using the photo CVD process. Therefore, the layer can be formed on the substrate in a shorter time than is needed by the photo CVD technique. Furthermore, even if the material for the layer is deposited on the interior surface of the reaction chamber as well as on the substrate, no limitations are imposed on the excitation of the reactive gas by electric power. Consequently, the layer can easily be formed to a desired thickness on the substrate.
With the plasma CVD technique, however, since the material gas excited by electric power is accelerated by an electric field, it is difficult to deposit the layer on the substrate without causing damage to its surface. On account of this, the layer contains the material forming the substrate surface, or the substrate surface contains the material forming the layer. Moreover, an interface level is set up between the layer and the substrate and internal stresses are applied to the layer and the substrate.
Besides, in the case of employing the plasma CVD technique, since the excited material gas is accelerated by an electric field and its free running In the reaction chamber is limited, there is the possibility that when the substrate surface is uneven, the layer cannot be formed in close contact therewith, that is, the layer cannot be deposited with desired characteristics.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a novel layer member forming method which is free from the abovesaid defects of the prior art.
The layer member forming method of the present invention comprises the steps of depositing a layer of a desired material on a substrate by the photo CVD technique and depositing on the first layer a second layer of a material identical with or different from that of first layer by the plasma CVD technique, thereby forming a layer member composed of at least the first and second layers.
According to such a method of the present invention, since the first layer is deposited by the photo CVD technique on the substrate, even if the substrate surface is uneven, the first layer can be deposited in close contact with the substrate surface and with substantially no damage thereon. Accordingly, the first layer does not substantially contain the material forming the substrate surface, or the substrate surface does not substantially contain the material forming the first layer. Further, the deposition of the first layer is not accompanied by provision of an undesirable interface level between the first layer and the substrate and the application of internal stresses to the first layer and the substrate. In addition, since the second layer is deposited by the plasma CVD technique on the first layer, the second layer can easily be formed to a desired thickness in a short time.
In accordance with an aspect of the present invention, by forming the first and second layers as insulating, protecting or conductive layers of the same or different types or compositions, the layer member as a insulating, protecting or conductive layer member of desired characteristics can easily be deposited to desired thickness in a short time without inflicting damage on the substrate surface.
In accordance with another aspect of the present invention, by forming the first and second layers as semiconductive layers of the same type or composition, the layer member as a semiconductor layer member can easily be deposited to a desired thickness in a short time without inflicting damage to the substrate surface.
In accordance with another aspect of the present invention, by forming the first and second layers as semiconductor layers of different types or compositions, the layer member can easily be deposited as a semiconductor layer member composed of a first semiconductor layer which may preferably be relatively thin and a second semiconductor layer which may preferably be relatively thick, in a short time without causing damage to the substrate surface.
In accordance with another aspect of the present invention, by forming the first and second layers as an insulating layers and as a conductive or semiconductor layer, respectively, the layer member as a composite layer member can easily be deposited including a conductive or semiconductor layer formed to a desired thickness on the insulating layer of the least possible thickness, in a short time without impairing the substrate surface.
In accordance with yet another aspect of the present invention, by forming the first and second layers as a conductive or semiconductor layer and as an insulating or protecting layer, respectively, the layer member as a composite layer member can easily be deposited including an insulating or protecting layer formed to a desired thickness on the conductive or semiconductive layer of the least possible thickness, in a short time without impairing the substrate surface.
Other objects, features and advantages of the present invention will become more fully apparent from the following description taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWING
The accompanying sheet of a drawing schematically illustrates an example of the layer forming method of the present invention and an example of apparatus used therefor.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A description will be given first of an apparatus for the formation of a layer member according to the present invention.
The apparatus has a conductive reaction chamber 10 . The reaction chamber 10 is provided with a plurality of conductive nozzles 11 arranged at the lower portion of the chamber 10 and each having upper and lower nozzle parts 12 a and 12 b . The conductive nozzles 11 are connected to one end of a power supply 15 for gas excitation.
A gas introducing pipe 13 is connected to the upper nozzle parts 12 a of the nozzle 11 and extends out of the reaction chamber 10 . The gas introducing pipe 13 is connected to a gas source 14 A via a valve 15 A and a flowmeter 16 A and to another gas source 14 B via a valve 15 B and a flowmeter 16 B.
Another gas introducing pipe 17 is connected to the lower nozzle parts 12 b of the nozzle 11 and extends out of the reaction chamber 10 . The gas introducing pipe 17 is connected to a gas source 18 A via a valve 18 A and a flowmeter 20 A, to a gas source 18 B via a valve 19 B and a flowmeter 20 B and to a gas source 18 C via a valve 19 C and a flowmeter 20 C.
The reaction chamber 10 is provided with an exhaust pipe 21 which extends to the outside through the bottom wall of its extending portion 10 ′ wherein the nozzles 11 are not placed. The exhaust pipe 21 is connected to a vacuum pump system 22 via a control valve 23 and a change-over valve 24 . The vacuum pump system 22 has a tandem structure of a turbo pump 25 and a rotary pump 26 .
Provided on the bottom wall of the reaction chamber 10 is a light source chamber 30 , in which is disposed light sources 31 each of which emits light having a wavelength 300 nm or less, such as a low pressure mercury lamp. The light sources 31 are connected to an external power supply (not shown). Provided on the bottom wall of the chamber 30 are cooling pipes 51 which are connected to a cooling tower (not shown).
The reaction chamber 10 and the light source chamber 30 optically intercommunicate through a window 33 made in, for instance, a quartz plate disposed therebetween.
The light source chamber 30 has a gas introducing pipe 34 which extends to the outside through its one end portion of the bottom wall. The gas introducing pipe 34 is connected to a gas source 35 via a valve 36 and folwmeter 37 . The light source chamber 30 has an exhaust pipe 38 which extends from the other end portion of the bottom wall of the chamber 30 into the extending portion 10 ′ of the reaction chamber 10 . A heater 39 is provided on the exhaust pipe 38 .
Disposed on the upper wall of the reaction chamber 10 is a heat source chamber 40 , in which is disposed a heat source 41 formed by, for example, a halogen lamp. The heat source 41 is connected to an external power supply (not shown). Provided on the top wall of the chamber 40 is costing pipes 61 which are connected to the abovesaid costing tower.
The reaction chamber 10 and the heat source chamber 40 thermally intercommunicate through a window 43 made in, for example, quartz plate disposed there between.
The light source chamber 40 has a gas introducing pipe 44 which extends through its one end portion of the upper wall to the outside and is connected to abovesaid gas source 35 via the valve 36 and the flowmeter 37 . The heat source chamber 40 has an exhaust pipe 48 which extends from its other end portion of the upper wall into the extending portion 10 ′ of the reaction chamber 10 . A heater 49 is provided on the exhaust pipe 48 .
The reaction chamber 10 has attached thereto on the side of its extending portion 10 ′ a substrate take-in/take-out chamber 70 with a shutter means 71 interposed therebetween. The shutter means 71 is selectively displaced to permit or inhibit the intercommunication therethrough between the chambers 10 and 70 .
The chamber 70 has another shutter means 72 on the opposite side from the shutter means 71 . The chamber 70 has an exhaust pipe 73 which extends from its bottom to the vacuum system 22 via the aforementioned change-over valve 24 . The chamber 70 has another pipe 75 which extends to the outside and terminates into the atmosphere via a valve 76 .
The apparatus includes a conductive holder 81 for mounting a plurality of substrate members 90 . The holder 81 is combined with thermally conductive press plates 82 for placing on the substrate members 90 mounted on the holder 81 .
According to an example of the present invention, the abovesaid layer member is deposited on the substrate member 90 through use of such an apparatus, as described hereinafter.
Embodiment 1
A description will given of a first embodiment of the present invention for forming the layer member as a insulating layer member on the substrate member 90 .
(1) The shutter means 71 between the reaction chamber 10 and the substrate take-in/take-out chamber 70 , the shutter means 72 of the chamber 70 a valve 76 between the chamber 70 and the outside, the valves 15 A and 15 B between the nozzle parts 12 a and the gas sources 14 A and 14 B, the valve 19 A, 19 B and 19 C between the nozzle parts 12 b and the gas sources 18 A, 18 B and 18 C and the valve 36 between the chambers 30 and 40 and the gas source 35 are closed.
(2) Next, the valve 23 between the reaction chamber 10 and the vacuum pump system 22 is opened and change-over valve 24 is also opened to the both chambers 10 , 70 , 30 and 40 to a pressure of 10 −7 Torr.
(3) Next, the turbo pump 25 and the rotary pump 26 of the vacuum pump system 22 are activated, evacuating the chambers 10 and 70 .
(4) Next, the valve 23 is closed and the change-over valve 24 is also closed relative to the both chambers 10 and 70 , followed by stopping of the vacuum pump system 22 from operation.
(5) Next, the valve 76 is opened, raising the pressure in the chamber 70 up to the atmospheric pressure.
(6) Next, the shutter means 72 is opened, through which the substrate 90 mounted on a holder 81 with, its surface for the formation thereon of the layer held down, is placed in the chamber 70 with a press plate 82 mounted on the substrate 90 .
(7) Next, the shutter means 72 and the valve 76 are closed.
(8) Next, the change-over valve 24 is opened to the chamber 70 alone and the pump system 22 is activated, evacuating the chamber 70 to substantially the same vacuum as that in which the chamber 10 is retained.
(9) Next, the change-over valve 24 is closed relative to the both chambers 10 and 70 and then the pump system 22 is stopped from operation.
(10) Next, the shutter means 71 is opened, the holder 81 carrying the substrate 90 is moved from the chamber 70 into the chamber 10 and disposed at a predetermined position in the upper part of the chamber 10 . At this time, the holder 81 is connected to the other end of the power source 15 .
(11) Next, the shutter means 71 is closed.
(12) Next, the heat source 41 in the heat source chamber 40 is turned ON, heating the substrate 90 up to a temperature of 350° C.
(13) Next, the light source 31 in the light source chamber 30 is turned ON.
(14) Next, the valve 19 A connected to the lower nozzle part 12 b of the nozzle 11 in the reaction chamber 10 is opened, through which ammonia gas (NH 3 ) is introduced as a first reactive material gas from the gas source 18 A into the chamber 10 . At the same time, the valve 23 is opened and the valve 24 is opened relative to the chamber 10 alone and, further, the pump system 22 is activated, raising the pressure in the chamber 10 to 3 Torr. Then the valve 15 B connected to the upper nozzle parts 12 a of the nozzle 11 is opened, through which disilane (Si 2 H 6 ) is introduced as a second reactive material ga from the gas source 14 B into the chamber 10 to provide therein a gas mixture of the ammonia gas and the disilane. The pressure in the chamber 10 is held at 3 Torr by regulating the valve 23 . In this instance, exhaust pipes 38 and 48 between the chambers 30 and 40 and the reaction chamber 10 are heated by heaters 39 and 49 mounted thereon, respectively. Even if the gas mixture flows back from the reaction chamber 10 in the pipes 38 and 48 toward the chambers 30 and 40 , it is vapor-decomposed by heat to deposit silicon nitride and silicon on the interior surfaces of the pipes 38 and 48 , preventing the silicon nitride and silicon from deposition on the inside surfaces of the chambers 30 and 40 . Furthermore, in order to prevent such a reverse flowing of the gas mixture, the valve 36 is opened, through which nitrogen or argon gas is introduced from the gas source 35 into the chambers 30 and 40 .
In such a condition, the gas mixture is excited by light from the light source 31 desposed in the light source chamber 31 , by which it is excited and vapor-decomposed, depositing a first silicon nitride layer as a first insulating layer on the substrate 90 at a rate of 17 A/min.
(15) Next, when the first silicon nitride layer is deposited to a thickness of about 500 A on the substrate 90 , the valve 23 is regulated and when the pressure in the chamber 10 is reduced to 1 Torr, the power source 15 is turned ON and then the light source 31 is turned OFF.
In such a condition, the gas mixture of the ammonia gas and the disilane is discharged or excited by electric power from the power source 15 into a plasma, in consequence of which a second silicon nitride layer is deposited as a second insulating layer on the first silicon nitride layer at a rate 2.1 A/sec.
(16) Next, when the second silicon nitride layer is deposited to a thickness of about 0.5 μm, the power source 15 is turned OFF and then the valves 15 B 19 A and 36 are closed but the valve 23 is fully opened, evacuating the chambers 10 and 30 to the same degree of vacuum as that under which the chamber 70 is held.
(17) Next, the valve 23 is closed and the pump system 22 is stopped and then the shutter means 71 is opened, through which the holder 81 carrying the substrate member 90 with the first and second insulating layers deposited thereon in this order is moved from the chamber 10 to the chamber 70 .
(18) Next, the shutter means 71 is closed and then the valve 76 is opened, through which the pressure in the chamber 70 is raised to the atmospheric pressure.
(19) Next, the shutter means 72 is opened, through which the holder 81 is taken out to the outside and then the substrate member 90 having formed thereon the first and second insulating layers is removed from the holder 81 .
In the manner described above, the insulating layer member as the layer member is formed on the substrate 90 .
(20) Next, the holder 81 with no substrate member 90 mounted thereon is placed in the chamber 70 , after which the shutter means 72 and the valve 76 are closed, the valve 24 is opened to the chamber 70 and the vacuum pump system 22 is put in operation, evacuating the chamber 70 to the same degree of vacuum as that under which the chamber 10 is retained.
(21) Next, the valve 24 is closed relative to the both chambers 70 and 10 , after which the shutter means 71 is opened, through which the holder 81 is placed in the chamber 10 , and then the shutter means 71 is closed.
(22) Next, the valve 19 B connected to the lower nozzle parts 12 b of the nozzle 11 is opened, through which nitrogen fluoride (NF 3 ) is introduced as a first cleaning gas form the gas source 18 B into the chamber 10 . On the other hand, the valve 23 is opened and the valve 24 is opened to the chamber 10 and then the pump system 22 is put in operation, holding the pressure in the chamber 10 at 0.1 Torr.
(23) Next, the power source 15 is turned ON.
In such a condition, the first cleaning gas is discharged or excited into a plasma by electric power from the power source 15 , etching away unnecessary layers deposited on the inside surface of the chamber 10 , the inside surfaces of the windows 33 and 34 , the outside surface of the nozzle 11 and the outside surface of the holder 81 . The unnecessary layers are composed of the materials of abovesaid first and second insulating layer.
(24) Next, when the unnecessary layers are almost etched away, the power source 15 is turned OFF and the valve 19 B is closed, but the valve 19 C is opened, through which hydrogen as a second cleaning gas, supplied from the gas source 18 C, is introduced into the chamber 10 , maintaining the pressure therein at 0.1 Torr.
(25) Next, the power source 15 is turned ON again. The second cleaning gas is discharged or excited into a plasma by electric power from the power source 15 , cleaning the interior of the reaction chamber 10 including the windows 33 and 34 , the nozzles 11 and the holder 81 .
(26) Next, the power source 15 is turned OFF, after which the valve 19 C is closed and the valve 23 is fully opened, through which the chamber 10 is evacuated. When the chamber 10 is evacuated to the same degree of vacuum as that under which the chamber 70 is retained, the valve 23 is closed, stopping the pump system 22 from operation.
Thus a series of steps for forming an insulating layer member as a layer member on a substrate is completed.
Embodiment 2
Next, a description will be given of a second embodiment of the present invention for forming a semiconductor layer member as a layer member on a substrate.
This embodiment forms an amorphous silicon layer as the semiconductor layer member on the substrate 90 by the same steps as those in Embodiment 1 except the following steps.
(12′) In step (12) in Embodiment 1 the heating temperature of the substrate 90 is changed from 350 C to 250 C.
(14′) In step (14) of Embodiment 1 only the disilane (Si 2 H 6 ) gas is introduced into the chamber 10 and the pressure in the chamber 10 is changed from 3 Torr to 2.5 Torr. A first amorphous silicon layer is deposited as a first semiconductor layer on the substrate 90 .
(15′) In step (15) of Embodiment 1, when the first amorphous silicon layer, instead of the first silicon nitride layer, is deposited about 1000 A thick on the substrate member 90 , the disilane is discharged or excited into a plasma in place of the gas mixture of the ammonia and disilane, by which a second amorphous silicon layer is deposited as a second semiconductor layer on the first amorphous silicon layer.
(16′) In step (16) of Embodiment 1, when the second amorphous silicon layer, instead of the silicon nitride layer, is deposited about 1000 A, the power source 15 is turned OFF.
Embodiment 3
Next, a description will be given of a third embodiment of the present invention which forms an aluminum nitride (AlN) layer member as a insulating layer member on a substrate.
Embodiment 3 employs a same steps as those in Embodiment 1 except the following steps.
(14′) In step (14) of Embodiment 1 methyl aluminum (Al(CH 3 ) 3 ), instead of the disilane, is introduced from the gas source 14 A into the chamber 10 , whereby a first aluminum nitride (AlN) layer is deposited as a first insulating layer on the substrate 90 . In this case, the deposition rate of the first aluminum nitride layer is 230 A/min.
(15′) In step (15) of Embodiment 1 a second aluminum nitride layer, instead of the second silicon nitride layer, is deposited on the first aluminum nitride layer.
While in the foregoing the present invention has been described in connection with the cases of forming an insulating layer member having two insulating layers of the same material and a semiconductor layer member having two semiconductor layers of the same material, it is also possible to form an insulating layer member which has two insulating or protecting layers of different materials selected from a group consisting of, for example, Si 3 N 4 , SiO 2 , phosphate glass, borosilicate glass, and aluminum nitride. Also it is possible that an insulating or protecting layer of, for instance, the abovesaid insulating or protecting material and a conductive layer of such a metal as aluminum, iron, nickel or cobalt are formed in this order or in the reverse order to form a composite layer member. Furthermore, a semiconductor layer of a material selected from the group consisting of, for example, Si, Si x C 1-x (where 0<x<1), SiM x (where 0<x<4 and M is such a metal as Mo, W, In, Cr, Sn or Ga) and the abovesaid insulating or protecting or conductive layer can also be formed in this order or in the reverse order to obtain a composite layer member. Moreover, although in the foregoing a low pressure mercury lamp is employed as the light source, an excimer laser (of a wavelength 100 to 400 nm), an argon laser and a nitrogen laser can also be used.
It will be apparent that many modifications and variations may be effected with out departing from the scope of the novel concepts of the present invention. | A vapor reaction method including the steps of providing a pair of first and second electrodes within a reaction chamber where the pair of electrodes are arranged substantially parallel with each other. The method further includes the steps of placing a substrate in the reaction chamber where the substrate is held by said first electrode so that a first surface of the substrate faces toward the second electrode. A first film forming gas is introduced into the reaction chamber through the second electrode. The first film forming gas is excited to form a first insulating film by vapor deposition. The first insulating film may be silicon nitride. The method may also include the step of introducing a second film forming gas into the reaction chamber through the second electrode to ultimately form a second film. After removing the substrate from the reaction chamber, a cleaning gas may then be introduced through the second electrode to remove unnecessary layers from the inside of the reaction chamber. | 2 |
BACKGROUND OF THE INVENTION
[0001] This invention relates to one-way clutches, which are common components in rotary mechanical power transmission systems. More specifically, the invention is an improvement on the planar “strut” type of one-way clutch as first seen in U.S. Pat. No. 5,670,978 and subsequent improvements sold under the Trademark, “Mechanical Diode” (®).
[0002] One-way clutches or OWC's as they are commonly known provide a variety of different functions in rotary power transmission systems such as safety devices for helicopter auto-rotation, hold-backs for conveyor systems and as shift components in automotive transmissions to name a few.
[0003] All OWC's including the planar type, require significant lubrication in high-speed applications to prevent wear and damage due to friction. The presence of fluid is more critical in the planar type of OWC as the lubrication serves as an active component in stabilizing the behavior of the strut when overrunning in excess of the maximum dry speed. This speed varies according to the actual geometry of the clutch but has been experimentally established at ˜2,000 RPM for the general example shown later in this discussion. In very high speed applications, all OWC's require a copious amount of lubricant flow to carry off waste heat generated as a consequence of fluid shear.
[0004] One problem currently not well addressed in all OWC's is in the rare occasions where system failure, contamination or momentary inertial forces cause a momentary cessation of lubricant flow. While damaging to all types of OWC's, this event can cause a rapid, catastrophic failure in a planar OWC.
[0005] In the example of helicopter auto-rotation this is very serious since the reason this safety feature might be needed is in the event of sudden loss of oil and the subsequent seizing of the engine and gear train.
[0006] Refinements have been made on the original strut geometry of planar OWC's that improve this situation so as to give a longer survivable time in an oil starved condition such as in U.S. Pat. No. 5,597,057 and U.S. Pat. No. 6,116,394. While this material shows an improvement, the techniques disclosed do not address the lack of stability of the strut but merely seek to restrain its resultant poor behavior. U.S. Pat. No. 6,116,394 describes the problem where unconstrained and deprived of fluid, the rear portion of the strut can enter the space of a notch and Impact with high force causing damage. U.S. Pat. No. 5,597,057 treats this by elongating the ears on the strut so that they protrude past the notch and will impact against the face of the notch plate rather than on a ramp of a notch. U.S. Pat. No. 6,116,394 shows a different strategy. It attempts to trap one edge of the strut between its pocket and the face of the notch plate so as to constrain its rotation in the event of oil loss.
[0007] In the particular case of an OWC with one member stationary and the other rotating, there is a simple solution that allows high-speed over running in the absence of fluid without strut failure. It is one purpose of this invention to show such a method.
[0008] Another purpose of this invention is to address the root cause of this failing in planar OWC design and remove the stimulus for bad behavior in those situations where the clutch is deprived of operating fluid. This is done by biasing the strut out of contact with the notch plate during overrun by utilizing the outward force generated by the strut carried by its pocket plate and to force a reaction with a cooperating feature on the pocket plate to counteract the bias of the engagement spring.
[0009] It is important to describe the sequence of events that cause catastrophic strut failure during high-speed, no-oil overrun in these prior art devices. FIG. 1 shows the general construction of a strut type planar clutch comprised of notch plate 7 , pocket plate 2 , strut 3 and spring 9 . FIGS. 2 through 4 show sequential cross-sectional views of a single strut 3 according to the prior art during over run with no oil.
[0010] First, according to FIG. 2, the strut 3 is biased upward into a passing notch 10 by its spring 9 . Next, the strut tip 11 is struck a glancing blow by the passing ramp of notch 10 , imparting a rotational moment about the strut 3 center of mass and also generating a downward thrust to the strut 3 . It is important to note that this initial impact is relatively small in magnitude. Now looking to FIG. 3, the strut impacts the bottom of its pocket 13 , rebounding upward and pivoting about the point of contact as can be seen in FIG. 4. The rear of the strut 3 continues to rise into an adjacent notch 10 . Finally, the rear of the strut 12 is struck smartly by that notch 10 ramp, imparting a large shock to the strut 3 .
[0011] It is this last impact in the series that imparts the damaging forces and velocities to the strut 3 . Since this last impact requires the strut 3 to be in an orientation contrary to the bias of the spring 9 , it does not happen normally but only as a consequence of the entire sequence of FIGS. 2 to 4 as described above and only in the absence of surrounding fluid.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] [0012]FIG. 1 is a cutaway perspective view of the prior art clutch.
[0013] [0013]FIG. 2 is a cross section view of the prior art clutch taken along lines 2 , 3 , 4 , of FIG. 1 approximately through the center of one strut and normal to centrifugal force acting on the strut.
[0014] [0014]FIG. 3 is a similar view of the prior art clutch to FIG. 2 showing the components later in the sequence.
[0015] [0015]FIG. 4 is a similar view of the prior art clutch to FIG. 3 showing the components still later in the sequence.
[0016] [0016]FIG. 5 is an exploded perspective view showing the components of the invention.
[0017] [0017]FIG. 6 is a cutaway perspective view.
[0018] [0018]FIG. 7 is an enlarged detail of the area noted in FIG. 6.
[0019] [0019]FIG. 8 is a side cutaway view corresponding to the lines 8 - 8 of FIG. 6 and sectioning one strut 17 parallel to the centrifugal force 24 (F 1 ).
[0020] [0020]FIG. 9 is a sketch showing the forces and geometry of the embodiment.
[0021] [0021]FIG. 10 is a schematic gear train diagram showing the proposed invention in its location in a typical application.
DETAILED DESCRIPTION
[0022] [0022]FIG. 5 is an exploded view of the assembly consisting of notch plate 15 , pocket plate 16 , a plurality of struts 17 carried by the pocket plate 16 , an outer strut support ring 20 and a retaining ring 18 . FIG. 6 shows these components in their assembled configuration. FIG. 7 is an enlarged view of the cutaway portion showing the components in more detail.
[0023] In operation, the outer component, the notch plate 15 is held stationary and the pocket plate 16 is connected to the desired element to be controlled. During over-run, the pocket plate 16 rotates clockwise 25 , in this example, and at high speed carrying the struts 17 , which are forced outward by momentum , F 1 indicated by the arrow 24 which is a function of the speed of rotation of the pocket plate 16 . This force 24 pushes angled strut faces 21 against the angled surfaces 23 of the outer strut support 20 thereby generating a force perpendicular to force 24 and counter to the bias of the spring 19 as seen in FIG. 8 thus preventing the strut 17 form tilting away from its pocket 16 and towards the notch plate 15 . When rotation of the pocket plate 16 exceeds a designed “sleep” speed, rotation of the strut 17 in any axis is inhibited by the forces generated by the cooperating angled strut edge 21 and the angled surface 23 , thereby keeping the strut 17 out of contact with the notch plate 15 .
[0024] At the point in time when the clutch is about to engage and lock (direction reversal), the rotational speed of the pocket plate 16 must match to the stationary notch plate 15 before reversing. Before this point is reached, the velocity drops below the calculated point of balance, the centrifugal force 24 on the strut 17 subsides and the spring 19 overcomes the forces generated by the angled surfaces 21 and 23 . Once this speed threshold is crossed, the strut 17 then behaves normally e.g. as the prior art devices operate. This normal behavior is only allowed at velocities below the critical limiting speed for dry over-running. Above the sleep speed, the struts 17 are inhibited from interacting with the notch plate 15 in any way, regardless of fluid condition.
[0025] [0025]FIG. 10 is a schematic drawing showing an example of this OWC invention 25 in use in a typical application involving speed reduction using a generic planetary gear set 24 . In this example, input rotation 27 is present at the sun gear 31 of the gear set 24 and the ring gear 29 becomes the output 28 . This common application can only function if the planet gear carrier 32 is constrained from rotating e.g. “is grounded”. Interposing the previously described OWC 25 between the planet carrier 32 and ground 26 will provide for an over-running output 28 that will function properly even in the intermittent absence of oil supply such as in the case desirable for Helicopter auto rotation.
[0026] When the input 27 is driving the output 28 at the designed ratio of the gear set 24 , the carrier 32 is forced in an absolute rotational direction e.g. relative to ground, similar to that rotational direction of the sun gear 31 . Constraining the carrier 32 to not rotate in this direction, via the lock function of the OWC assembly 25 , allows the gear set 24 to function and thereby drive the output 28 at the required ratio.
[0027] In the case where the input rotation 27 ceases, or in other general cases where output 28 over-running of the input 27 prescribed speed is desired, The output 28 is now pulling the input 27 rather than being pushed by it and therefore all forces in the assembly reverse. This force reversal urges the carrier 32 to rotate in a direction, relative to ground 26 , opposite to the driving case above and the one-way clutch assembly 25 unlocks in response to this direction reversal allowing the free over-run of the output 28 at a velocity greater than that prescribed by the input 27 .
[0028] As previously described, the grounded member of this OWC 25 , is the notch plate 34 , similar to that described as 15 . The rotating member connected to the carrier 32 is the pocket plate previously described as 16 . When the output 28 described above over-runs the input 27 , the pocket plate 33 of OWC assembly 25 is forced to rotate, relative to ground 26 , in its over-running direction. In the case where this rotational speed becomes too fast for safe, oil free, operation, the inventive features previously described come into play to inhibit contact of the orbiting struts carried by pocket plate 33 with the stationary notch plate 34 .
[0029] Going back to FIG. 8, the strut 17 behavior is controlled as a function of the rotational speed of the pocket plate 16 , which happens to be clockwise 24 in this example. Different rotational directions or switching of the pocket plate 16 and notch plate 15 as inner and outer members are obvious and does not avoid the invention herein. Similarly, the notch plate 15 is not required to be stationary so long as the absolute velocity of the pocket plate 16 controls the behavior of the struts 17 within the bounds of an acceptable “dry” rotational speed difference between pocket plate 16 and notch plate 15 and as long as the point of relative rotation reversal between the two members allows an absolute pocket plate 16 rotational velocity below the sleep threshold.
[0030] As an actual example, A clutch having struts 17 radially positioned at 2.5 inches from the axis of rotation will retract its struts 17 and not interact with the stationary notch plate 15 at approximately 790 RPM speed of the pocket plate 16 if the geometry defined in FIG. 9 is used with a strut 17 mass of 0.08 ounces. This “sleep” speed can be tuned by varying the mass and geometry of the strut 17 , as well as the spring 19 force in accordance with the equation provided below and according to FIG. 9.
ω 2 = ( F s D s - F 2 D 2 ) g D 1 W r
[0031] Where:
[0032] ω—Clutch pocket plate angular velocity
[0033] F S —Spring force in the strut down position
[0034] D S —Distance from strut inner angled edge to spring force
[0035] D 1 —One-half of the strut thickness
[0036] D 2 —Planar distance between the wedge side strut edges
[0037] F 2 —Cam down force exerted by the wedge
[0038] W—Strut weight
[0039] r—Distance from MD axis to strut center of mass
[0040] g—Gravitational Constant | A planar type of over-running clutch including first and second confronting plates is disclosed herein. The second plate itself includes movable struts and associated biasing mechanisms for cooperative engagement with cooperating shoulder members of the first plate under certain circumstances. An arrangement forming part of said second plate and cooperating with each strut and biasing mechanism of said second plate is provided for preventing the struts from moving to certain biased first positions when said second plate rotates in a particular way. | 5 |
FIELD OF THE INVENTION
[0001] The invention relates to the use of synergistic mixtures of phytostenols or phytostenol esters and conjugated fatty acids for producing preparations for decreasing the cholesterol content in the serum of warm-blooded animals.
PRIOR ART
[0002] Hypocholesteremic active agents are understood as meaning preparations which lead to a decrease in the cholesterol content in the serum of warm-blooded animals without an inhibition or lowering of the formation of cholesterol in the blood occurring. Phytostenols, i.e. plant stenols, and their esters with fatty acids have already been proposed for this purpose by Peterson et al. in J. Nutrit. 50, 191 (1953). The patent Specifications U.S. Pat. No. 3,089,939, U.S. Pat. No. 3,203,862 as well as the German Laid-Open Specification DE-A 2035069 (Procter & Gamble) also point in the same direction. The active agents are customarily added to cooking or food oils and then ingested via the food, the amounts employed, however, as a rule being low and customarily below 0.5% by weight in order to prevent the food oils from becoming cloudy or the stenols from being precipitated on addition of water. For use in the foodstuffs area, in cosmetics, pharmaceutical preparations and in the agrarian sector, storage-stable emulsions of the stenol esters in sugar or polyglycerol esters are proposed in European Patent Application EP-A1 0289636 (Ashai). The incorporation of sitostanol esters to decrease the blood cholesterol content in margarine, butter, mayonnaise, salad dressings and the like is proposed in European Patent Specification EP-B1 0594612 (Raision).
[0003] The disadvantage, however, is that the phytostenol esters can customarily be added to the food-stuffs only in small amounts, as otherwise there is the danger that they will impair the taste and/or the consistency of the preparations. For a lasting effect on the cholesterol content in the blood, however, the intake of larger amounts of phytostenols or phytostenol esters would be desirable. Furthermore, the rate at which the substances decrease the content of cholesterol in the serum is worthy of improvement. The object of the invention consequently consisted in remedying these deficiencies.
DESCRIPTION OF THE INVENTION
[0004] The invention relates to the use of mixtures of active agents for producing hypocholesteremic preparations with the proviso that
(a) phytostenols and/or phytostenol esters and (b) fatty acids having 6 to 24 carbon atoms and at least two conjugated double bonds or their glycerides
are employed.
[0007] Surprisingly, it has been found that mixtures of phytostenols or phytostenol esters with conjugated fatty acids or fatty acid glycerides synergistically cause the reduction of the cholesterol content in the blood serum. Encapsulated in gelatin or directly added to foodstuffs, both the mixtures of active agents can be taken orally without problems.
[0000] Phytostenols and Phytostenol Esters
[0008] Phytostenols (or synonymously phytosterols) are understood as meaning plant steroids which carry a hydroxyl group only on C-3, but otherwise no functional groups. As a rule, the phytostenols have 27 to 30 carbon atoms and a double bond in the 5/6, optionally 7/8, 8/9 or other positions. In addition to these unsaturated species, suitable stenols are also the saturated compounds obtainable by hardening, which are designated stanols and are additionally included by the present invention. Typical examples of suitable phytostenols are, for example, ergostenols, campestenols, stigmastenols, brassica stenols, and preferably sitostenols or sitostanols and in particular β-sitostenols or β-sitostanols. In addition to the phytostenols mentioned, their esters are preferably employed. The acid component of the ester can have its origin in carboxylic acids of the formula (I)
R 1 CO—OH (I)
in which R 1 CO is an aliphatic, linear or branched acyl radical having 2 to 22 carbon atoms and 0 and/or 1, 2 or 3 double bonds. Typical examples are acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, 2-ethylhexanoic acid, capric acid, lauric acid, isotridecanoic acid, myristic acid, palmitic acid, palmitoleic acid, stearic acid, isostearic acid, oleic acid, elaidic acid, petroselinic acid, linoleic acid, linolenic acid, elaeostearic acid, arachic acid, gadoleic acid, behenic acid and erucic acid, and their technical mixtures, which are obtained, for example, in the pressure cracking of natural fats and oils, in the reduction of aldehydes from Roelen's oxo synthesis or the dimerization of unsaturated fatty acids. Preferred technical fatty acids are those having 12 to 18 carbon atoms such as, for example, coconut, palmitic, palm kernel or tallow fatty acid. The use of esters of β-sitostenol or β-sitostanol with fatty acids having 12 to 18 carbon atoms is particularly preferred. These esters can be produced both by direct esterification of the phytostenols with the fatty acids or else by transesterification with fatty acid lower alkyl esters or triglycerides in the presence of suitable catalysts, such as, for example, sodium ethylate or especially also enzymes [cf. EP-A2 0195311 (Yoshikawa)]. The hypocholesteremic action of phytostenols or phytostenol esters is disclosed, for example, in European Patent Specification EP-B1 0594612 (Raision) and the literature cited therein.
Conjugated Fatty Acids
[0009] The term conjugated fatty acids is understood as meaning aliphatic carboxylic acids having 6 to 24, preferably 16 to 18, carbon atoms and at least two double bonds which are conjugated to one another, i.e. are separated by exactly one single bond. Typical examples are the conjugated linoleic acid (CLA) or conjugated fish fatty acids. It is known of conjugated linoleic acid that it has a low hypocholesteremic action; its use in foodstuffs or as a foodstuff supplement, however, is attributed to the fact that it assists the combustion of endogenous fats [cf. EP-B1 0579901, WO 94/16690, WO 96/06605; (WARF)]. Instead of the conjugated fatty acids, the corresponding full or partial esters with glycerol can also be employed for reasons of taste and because of the better fat solubility.
[0000] Tocopherols
[0010] The mixtures of active agents may contain potentiating agents of the tocopherols type as further constituents. Tocopherols are understood as meaning chroman-6-ols (3,4-dihydro-2-H-1benzopyran-6-ols) substituted in the 2-position by 4,8,12-trimethyl-tridecyl radicals, which obey the formula (II)
in which R 2 , R 3 and R 4 independently of one another are hydrogen or a methyl group. Tocopherols belong to the bioquinones, i.e. polyprenylated 1,4-benzo- or naphthoquinones whose prenyl chains are saturated to a greater or lesser extent. Typical examples of tocopherols which are possible within the meaning of the invention as component (b) are ubiquinones, boviquinones, K vitamins and/or menaquinones (2-methyl-1,4-naphthoquinones). In the case of the tocopherols, a differentiation is furthermore made between α, β, γ-, δ- and ε-tocopherols, where the latter can still have the original unsaturated prenyl side chain, and α-tocopherolquinone and -hydroquinone, in which the pyran ring system is opened. Preferably, as component (b), α-tocopherol (vitamin E) of the formula (II) is employed, in which R 2 , R 3 and R 4 are methyl groups, or esters of α-tocopherol with carboxylic acids having 2 to 22 carbon atoms, such as, for example, α-tocopherol acetate or α-tocopherol palmitate.
Chitosans
[0011] As further constituents, the mixtures of active agents can contain potentiating preparations of the chitosans type. Chitosans are biopolymers and are included in the hydrocolloids group. Considered chemically, they are partially deacetylated chitins of different molecular weights, which contain the following—idealized—monomer unit (III)
[0012] In contrast to most hydrocolloids, which are negatively charged in the biological pH region, chitosans are cationic biopolymers under these conditions. The positively charged chitosans can interact with oppositely charged surfaces and are therefore employed in cosmetic hair- and body-care preparations and pharmaceutical preparations (cf. Ullmann's Encyclopedia of Industrial Chemistry, 5th Ed., Vol. A6, Weinheim, Verlag Chemie, 1986, pp. 231-332). Overviews on this subject have also appeared, for example, by B. Gesslein et al. in HAPPI 27, 57 (1990), O. Skaugrud in Drug Cosm. Ind. 148, 24 (1991) and E. Onsoyen et al. in Seifen-Öle-Fette-Wachse 117, 633 (1991). To produce chitosans, chitin, preferably the shell remains from crustaceans, which are available in large amounts as cheap raw materials, is used as a starting material. In a process which has been described for the first time by Hackmann et al., the chitin is customarily first deproteinated by addition of bases, demineralized by addition of mineral acids and finally deacetylated by addition of strong bases, it being possible for the molecular weights to be distributed over a wide spectrum. Corresponding processes are known, for example, from Makromol. Chem. 177, 3589 (1976) or French Patent Application FR-A 2701266. In a preferred embodiment of the invention, a chitin degradation product, as is described in International Patent Application WO 96/16991 (Henkel), or its degradation product with hydrogen peroxide is employed.
[0000] Phytostenol Sulfates
[0013] The mixtures of active agents can contain potentiating preparations of the phytostenol sulfates type as further constituents. Phytostenol sulfates are known substances which can be prepared, for example, by sulfation of phytostenols with a complex of sulfur trioxide and pyridine in benzene [cf. J. Am. Chem. Soc. 63, 1259 (1941)]. Typical examples are the sulfates of ergostenols, campestenols, stigmastenols and sitostenols. The phytostenol sulfates can be present as alkali metal and/or alkaline earth metal salts, as ammonium, alkylammonium, alkanolammonium and/or glucammonium salts. As a rule, they are employed in the form of their sodium salts.
[0000] (Deoxy)ribonucleic Acids
[0014] The mixtures of active agents can finally contain potentiating preparations of the (deoxy)ribonucleic acids type as further constituents. (Deoxy)ribonucleic acids (DNA or RNA) are understood as meaning high molecular weight, threadlike polynucleotides which are derived from 2′-deoxy-β-D-ribonucleosides or D-ribonucleosides, which for their part in turn are synthesized from equivalent amounts of a nucleobase and the pentose 2-deoxy-D-ribofuranose or D-ribofuranose. As nucleobases, the DNA or RNA can contain the purine derivatives adenine and guanine and also the pyrimidines cytosine and thymine or uracil. In the nucleic acids, the nucleobases are linked N-glycosidically with carbon atom 1 of the ribose, adenosines, guanosines, cytidines and thymidines being formed in the individual case. In the acids, a phosphate group links the 5′-hydroxyl group of the nucleosides with the 3′-OH group of the following nucleoside in each case by means of a phosphodiester bridge with formation of single-stranded DNA or RNA. Because of the large ratio of length to diameter, DNA and RNA molecules are prone, even on mechanical stress, for example during extraction, to strand breakage. For this reason, the molecular weight of the nucleic acids can reach 10 3 to 10 9 daltons. Within the meaning of the invention, concentrated DNA and RNA solutions are employed, which are distinguished by a liquid-crystalline behavior. Preferably, deoxy- and ribonucleic acids are employed which are obtained from marine sources, for example by extraction of fish sperm, and which have a molecular weight in the region from 40,000 to 1,000,000 daltons.
[0000] Commercial Applicability
[0015] The mixtures of active agents of the invention can contain the phytostenols and/or phytostenol esters and the conjugated fatty acids in the weight ratio 99:1 to 1:99, preferably 90:10 to 10:90, in particular 75:25 to 25:75 and particularly preferably 60:40 to 40:60. In a particular embodiment of the invention, the mixtures of active agents are encapsulated in gelatin in a manner known per se, components (a) and (b) in each case being employed in amounts from 0.1 to 50, preferably 1 to 30, in particular 5 to 25 and particularly preferably 10 to 15, % by weight—based on the weight of the gelatin capsules. In addition, it is possible to dissolve or to disperse the mixtures in customary foodstuffs, such as, for example: butter, margarine, dietetic food, deep-frying oils, food oils, mayonnaises, salad dressings, cocoa products, sausage and the like.
EXAMPLES
Examples 1 to 5, Comparative Examples C1 to C5
[0016] Gelatin capsules (weight about 1.5 g) having a content of 5 or 10% by weight of β-sitostenol or β-sitostenol ester and, if appropriate 5 or 10% by weight of conjugated linoleic acid (CLA) and also 0.5% by weight of radiolabeled cholesterol were prepared. To investigate the hypocholesteremic action, male rats (individual weight about 200 g) were allowed to fast overnight. The following day, a comminuted gelatin capsule was introduced into the experimental animals in each case with some salt-containing water by means of a stomach tube. After 3, 6, 12, 24 and 48 h, blood was taken from the animals and the content of radioactive cholesterol was determined. The results, which represent the mean value of the measurements of 10 experimental animals, are summarized in Table 1. The details on the decrease in the radioactivity are in each case interpreted with respect to a blind group of experimental animals, to which only gelatin capsules having a content of 20% by weight of vitamin E and an appropriate amount of radiolabeled cholesterol had been administered. The mixtures 1 to 5 are according to the invention; the mixtures C1 to C5 serve for comparison.
TABLE 1 Hypocholesteremic action (quantitative data as % by weight based on gelatin capsule) Composition 1 2 3 4 5 C1 C2 C3 C4 C5 β-Sitostenol 5 — — — — 10 — — — — β-Sitostanol — 5 — — — — 10 — — — Lauric acid β-sitostenol — — 5 — — — — 10 — — ester Lauric acid β-sitostanol — — — 5 10 — — — 10 — ester Conjugated linoleic acid 5 5 5 5 5 — — — — 10 Radioactivity [% rel] after 3 h 93 93 93 93 93 93 93 93 93 98 after 6 h 84 83 83 83 81 87 86 87 86 91 after 12 h 75 75 75 74 71 79 79 78 78 87 after 24 h 54 51 47 45 40 62 60 59 69 75 after 48 h 23 21 22 19 12 35 32 35 32 60
[0017] The examples show the synergistic decrease in the cholesterol content in the blood when using mixtures of the stenols or stenol esters with CLA. | A hypocholesteremic preparation containing at least one component (a) selected from the group consisting of phytostenols and phytostenol esters and at least one component (b) selected from conjugated fatty acids having from about 6 to about 24 carbon atoms and glycerides of conjugated fatty acids having from about 6 to about 24 carbon atoms is disclosed. Methods of reducing serum cholesterol content in a mammal via administration of hypocholesteremic preparations described herein are also disclosed. | 0 |
BACKGROUND
The present invention relates to a reset controller for a domino circuit characterized by improved turn off times.
As is known, integrated circuits may include domino circuits that carry active data on only one phase of a driving clock, called the “evaluation phase.” During another phase of the clock, the “precharging phase,” the domino circuit precharges its output to a predetermined value. A reset circuit in the domino circuit controls the precharging.
An evaluation circuit also is coupled to the output terminal having a data input terminal. If active data is input to the evaluation circuit during the evaluation phase, the evaluation circuit may drive the output terminal from the precharge voltage. The active data typically is removed from the evaluation circuit prior to the precharge phase. The reset circuit precharges the output terminal in preparation for another evaluation phase.
Known reset circuits may include a propagation path that extends from the output terminal to a precharge transistor. An output of the reset circuit drives the gate of the precharge transistor. Such reset circuits typically are characterized by a propagation delay that is sufficient to guarantee that the reset circuit will not cause the precharge transistor to precharge the output terminal at the same time that the evaluation terminal causes the output terminal to be driven to a different potential. If two transistors were permitted to drive the same terminal to two different potentials, it would cause contention and damage to the circuit. Thus, the delay of the reset circuit typically is designed to be large enough so that the precharge transistor is turned on only after the data signal that is input to the evaluation circuit is deactivated.
In known self-resetting domino circuits, the reset circuit that turns on the precharge transistor also turns it off. Thus, after the precharge circuit is activated, it remains activated for the same propagation delay that was designed into the reset circuit to avoid contention.
This feature of reset circuits may be disadvantageous. Although a relatively long delay in turning the precharge transistor on may be necessary to avoid contention at the output terminal, a long delay in turning off the precharge transistor is not necessary. An output terminal may be precharged very quickly relative to the length of the data pulse input to the domino circuit. No known reset circuit provides a different delay for activating a precharge transistor than for deactivating a precharge transistor.
Accordingly, there is a need in the art for a reset circuit in a domino circuit that provides activates a precharge transistor after a first delay but deactivates the precharge transistor after a second, shorter delay.
SUMMARY
According to an embodiment, the present invention provides a method of precharging a node in an integrated circuit in which the node is precharged a first predetermined delay after the node evaluates and, thereafter, the precharge ceases after a second shorter predetermined delay.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram of self-timed atomic circuit constructed in accordance with an embodiment of the present invention.
FIG. 2 is a timing diagram of the atomic circuit of FIG. 1 operating in accordance with an embodiment of the present invention.
FIG. 3 is diagram of a self-timed atomic circuit constructed in accordance with another embodiment of the present invention.
FIG. 4 is diagram of a self-timed atomic circuit constructed in accordance with yet another embodiment of the present invention.
DETAILED DESCRIPTION
Embodiments of the present invention provide domino circuit having a self-timed reset circuit in which the reset circuit is characterized by a long delay path to enable the reset precharge and also a short delay path to disable the reset precharge once the reset is activated. An understanding of these embodiments may be facilitated by reference to the figures and the following description.
FIG. 1 is a circuit diagram of a domino circuit 100 according to an embodiment of the present invention. The domino circuit 100 includes an output terminal 110 that is precharged to a predetermined potential (the “precharge” or “standby” potential). In the example of FIG. 1, the output terminal 110 is precharged to V cc . The domino circuit 100 includes an evaluate circuit 120 having an input terminal 130 . The evaluate circuit 120 couples the output terminal 110 to a second predetermined potential, shown as ground in FIG. 1 (the “evaluation” potential). During the evaluation phase, the evaluate circuit 120 may cause the output terminal 110 to discharge to ground based upon the state of the signal at input terminal 130 .
In the example of FIG. 1, the domino circuit 100 is shown as a latch circuit. Of course, as is understood by those of skill, the domino circuit 100 may be designed to accommodate a host of logical functions. As is known, different applications of the present invention may cause the nature and character of the evaluate circuit 120 to deviate from the structure shown in the present invention. Such deviations are within the spirit of the present invention.
The domino circuit 100 also may include a precharge transistor 140 that couples the output terminal 110 to the precharge potential across a source to drain path. A reset circuit 150 couples the gate 141 of the precharge transistor 140 to the output terminal 110 . The precharge transistor 140 may be a PMOS transistor that is conductive when the signal applied at the gate 141 goes low. When the precharge transistor 140 is conductive, it pulls the voltage at the output terminal to the precharge potential.
According to an embodiment of the present invention, the reset circuit 150 may be populated by two circuit paths, a “long delay path” 160 and a “short delay path” 170 , each extending from the output terminal 110 to the gate 141 of the precharge transistor 140 . The two paths each are input to a common NAND gate 151 .
The long delay path 160 and the short delay path 170 each may be populated by one or more inverter buffers 161 - 163 , 171 . The inverter buffers of each path 160 , 170 are interconnected in a cascaded relationship. As is known, each inverter buffer imposes a propagation delay upon an input data signal; the number of inverter buffers in each path 160 , 170 determines how much delay the respective path imposes upon a signal as it propagates from the output terminal 110 through the respective path to the NAND gate 151 . The NAND gate 151 itself may impose a propagation delay upon an input signal.
In the example of FIG. 1, only one inverter buffer 171 is shown in the short delay path 170 and three inverter buffers 161 - 163 are shown in the long delay path 160 . These numbers are merely exemplary. Typically, the number of inverters in a particular domino circuit 100 will be tuned to the application for which the circuit 100 is to be used.
For notational purposes, the input from the long delay path 160 to the NAND gate 151 is labeled node “A” and the input from the short delay path 170 to the NAND gate 151 is labeled node “B.” An output of the NAND gate 151 is input to the gate of the precharge transistor 140 at a node “C.”
FIG. 2 is a timing diagram illustrating the state of signals in the domino circuit 100 of FIG. 1 according to an embodiment of the present invention. In the example of FIG. 2, the inverter buffers 161 - 163 , 171 are assumed to impose an identical propagation delay upon a signal. FIG. 2 illustrates signals at the input terminal 130 , at nodes A-C and at the output terminal 110 . The dashed lines represent time samples measured in units of delay imposed by a single inverter buffer.
During a rest state, the data signal at terminal 120 is precharged to the precharge potential. Assume that the output terminal 110 is precharged to a high state but that no external source maintains the output terminal 110 at such a state. Nodes A and B therefore are low. The input to the precharge transistor 140 (node C), therefore, is high. Thus, both the evaluate circuit 120 and the precharge transistor 140 are nonconductive.
The data signal is shown as evaluating in sample 1. When the data signal evaluates, the evaluate circuit 120 conducts and discharges the output terminal 110 to ground. Thus, the inputs to both the long delay path 160 and the short delay path 170 are low. The exemplary data signal is shown as being low for over three samples. It drives the output terminal 110 to ground during the time that the data signal is in the evaluate state.
At sample 3, the signal at the output terminal 110 will have propagated through the short delay path 170 . Thus, node B is shown as being high. But the data signal will not have propagated through the long delay path 160 (Node A remains low). The output of the NAND gate 151 (node C) does not change. The precharge transistor 140 remains nonconductive. The output terminal 110 remains driven to ground by the data signal.
As shown in FIG. 2, sometime during the duration of sample 4, the data signal ceases to evaluate and returns to its high state. The evaluate circuit 120 no longer drives the output terminal 110 low. Although no longer driven to ground, the output terminal 110 will remain at ground until driven by some other potential.
At sample 5, the data signal that was input to the long delay path 160 in sample 1 will have propagated through the long delay path 160 . Thus, nodes A and B both are high. The NAND gate 151 goes low and the precharge transistor 140 conducts. When the precharge transistor 140 conducts, the output terminal 110 is driven to the precharge potential. The precharge potential is input to the two paths 160 , 170 of the reset circuit 150 .
At sample 8, the state change at the output terminal (sample 7) will have been inverted by inverter 171 and input to NAND gate 151 . The input from the long delay path 160 does not change. Thus, node B will be low but node A will remain high. The output of the NAND gate 150 (node C) goes high and the precharge transistor 140 ceases to conduct. The output terminal 110 remains at the precharge potential but is no longer driven so. It is precharged and ready for the next evaluation phase.
As shown in FIG. 2, the delay of the long delay path 160 (in combination with delays that may be introduced by the NAND gate 151 and precharge transistor 140 ) determines the time when the precharge transistor 140 precharges the output terminal 110 . Typically, the delay path 160 may be tuned to a period that is longer than the duration of the input data pulse so as to ensure there will be no contention between the evaluate circuit 120 and the precharge transistor 140 . Such tuning may require calibrating a number of inverter buffers in the delay path 160 to introduce a desired propagation delay to the path.
Also as shown in FIG. 2, the delay of the short delay path 170 (again, in combination with delays that may be introduced by the NAND gate 151 and precharge transistor 140 ) determines the time after the precharge begins when the precharge transistor 140 ceases to precharge the output terminal. In an embodiment, this path may be tuned to maintain the precharge transistor 140 conductive only so long as may be required to precharge the output terminal 100 . Such an embodiment increases the speed at which the domino circuit 100 may receive a new data signal and, therefore, increases the throughput of the system as a whole.
FIG. 3 illustrates a domino circuit 200 constructed in accordance with another embodiment of the present invention. The domino circuit 200 may be populated by an output terminal 210 and input terminal 220 . An evaluate circuit 230 couples the output terminal to an evaluation potential (such as ground) and a precharge transistor 240 couples the output terminal to a precharge potential (such as V cc ). A reset circuit 250 couples the output terminal to the gate of the precharge circuit.
According to an embodiment of the present invention, the reset circuit 250 provides a short delay path 260 and a long delay path 270 from the output terminal 210 to the gate 241 of the precharge transistor 240 . A NAND gate 251 receives inputs from the two delay paths 260 , 270 and has an output coupled to the gate 241 of the precharge transistor 240 . The long delay 270 path includes a cascaded chain of inverter buffers 271 - 273 extending from the output terminal 210 to the NAND gate 251 . The short delay path 260 provides a shunt path from an intermediate point in the chain of inverter buffers to a second input of the NAND gate 251 . In the exemplary reset circuit 250 of FIG. 3, an output of the first inverter buffer 273 is input directly to the NAND gate 241 . Thus the short delay path 260 includes a fewer number of inverter buffers than would the long delay path 270 .
The embodiment of FIG. 3 operates in a similar manner to the embodiment of FIG. 1 particularly as it relates to the signals and timing shown in FIG. 2 . However, the embodiment of FIG. 3 includes fewer inverter buffers than that of FIG. 1 . Thus, the embodiment of FIG. 3 may be preferable for use in integrated circuits where it is desired to conserve elements and chip area.
FIG. 4 illustrates a domino circuit 300 according to yet another embodiment of the present invention. FIG. 4 illustrates use of the present invention in an embodiment where the precharge potential is V ss (ground) and the evaluation potential is V cc . The domino circuit 300 may include an output terminal 310 , an evaluation circuit 320 , an input terminal 330 and a precharge circuit 340 .
The domino circuit further may include a reset circuit 350 having a short delay path 360 and a long delay path 370 . Each delay chain may include a chain of cascaded inverter buffers, each chain having an input coupled to the output terminal 310 . The short delay path 360 may include a smaller number of inverter buffers than the long delay path. Outputs of the two delay chains 360 , 370 may be input to a NOR gate 351 . An output of the NOR gate may be input to the precharge circuit 340 .
Several embodiments of the present invention are specifically illustrated and described herein. However, it will be appreciated that modifications and variations of the present invention are covered by the above teachings and within the purview of the appended claims without departing from the spirit and intended scope of the invention. | A method is provided for precharging a node in an integrated circuit in which the node is precharged a first predetermined delay after the node evaluates and, thereafter, the precharge ceases after a second shorter predetermined delay. | 7 |
BACKGROUND OF THE INVENTION
In treating the leg and knee, particularly when fitting orthosis apparatus to the leg and knee, it is desirable to be able to accurately measure the dimensions of the leg and knee and compare the limb measurements to a reference point. As each person's leg differs, to produce an orthosis of maximum efficiency and comfort accurate measurements are highly desirable, but heretofore, were not readily obtainable.
Various devices for measuring the position and movement of human limbs are known, typical devices being shown in U.S. Pat. Nos. 3,020,639; 4,436,099 and 4,742,832. However, known orthosis measuring devices are expensive, cumbersome to install and use, and require highly skilled technicians.
It is an object of the invention to provide an orthosis device for the leg and knee which is of economical manufacture, readily applied to the patient, is capable of providing accurate limb measurements relative to a reference, and may be utilized by technicians having limited skills.
A further object of the invention is to provide an orthosis measurement device for the leg and knee which is lightweight, easy to use, and permits a plurality of measurements to be quickly taken at various locations along the leg.
Yet another object of the invention is to provide a leg and knee orthosis measuring device wherein a plurality of portions of the leg may be quickly measured with respect to a reference column mounted in a predetermined manner to the leg.
In the practice of the invention an elongated column is attached to the leg front portion in a relatively parallel relationship. Pads mounted at the upper and lower regions of the column are strapped to the leg wherein the column constitutes a reference element or line with respect to the approximate center line of the leg, and a measurement device selectively movable along the column contains probes for engaging the leg and permitting measurement of the leg relative to the column.
The measurement device comprises a caliper-like apparatus using a pair of spaced probes movable toward and away from each other. The probes are mounted upon a guide having a scale defined thereon whereby the distance of the probe from the column is immediately ascertainable. A plurality of reference indices are defined along the column whereby the measurement apparatus may be selectively raised or lowered to known locations, and the measurement devices utilize a spring biased detent for selectively engaging an index recess defined on the column.
By sliding the probe along the guide for engagement with the side of the leg the transverse location of the engaged portion of the leg relative to the column may be quickly determined by reference to the guide scale, and an operator may take a plurality of leg measurements at various locations along the leg and column in a short time without discomfort or inconvenience to the patient.
BRIEF DESCRIPTION OF THE DRAWINGS
The aforementioned objects and advantages of the invention will be appreciated from the following description and accompanying drawings wherein:
FIG. 1 is a perspective view of leg and knee orthosis measuring apparatus in accord with the invention,
FIG. 2 is a front elevational view illustrating the apparatus of the invention as mounted upon the leg of a patient,
FIG. 3 is a plan sectional view as taken along a Section III--III of FIG. 1,
FIG. 4 is an enlarged, elevational, sectional view as taken through the upper pad along Section IV--IV of FIG. 1,
FIG. 5 is an elevational sectional view of the guide and probe inner end as taken along Section V--V of FIG. 3, and
FIG. 6 is an elevational view taken through the measurement carriage along Section VI--VI of FIG. 3.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The orthosis measuring device of the invention includes a column 10 such as formed of a cylindrical one half inch diameter rod or tube having an upper end region 12 and a lower end region 14 with the intermediate region 16 being defined therebetween. The upper and lower ends of the column may have caps 17 placed thereon for decorative and protection purposes. A pad indicated at 18 is located upon the column upper end region while a lower pad assembly 20 is mounted upon the column lower end region. The leg measurement means 22 is mounted upon the column intermediate region 16 for selective movement thereon in a vertical direction.
The column mounting pads 18 and 20 are identical except that the upper pad 18 is of a larger dimension in that the pad 18 is associated with the wearer's thigh while the smaller lower pad 20 is mounted to the wearer's ankle. As the structural components of the pads are identical the lower pad components are identified by primed reference numerals.
The pads are attached to the column 10 by blocks 24 and 24' and the blocks each include a vertical bore 26 which slidably receives the column. A set screw and knob assembly 28 and 28' is associated with each of the blocks 24 and 24', respectively, and the set screw assemblies are threaded into threaded holes defined in the associated block intersecting the associated bore 26 for engaging the column and axially and rotatably fixing the associated block to the column.
The pads also each include a synthetic plastic sheet 30 and 30' of a generally rectangular configuration interiorly lined by the foam liner 32 which is bonded to the associated sheet. The sheet and liner assembly is attached to the associated block 24 and 24' by screws 34, FIG. 4.
Straps 36 and 36' are associated with the ends of the pads 18 and 20, respectively, and the straps are mounted to the sheets 30 and 30' and include a buckle 38 and 38' whereby the lengths of the straps can be readily adjusted in the known manner.
The measurement device 22 includes a block-like carriage 40 having a vertical bore 42, FIG. 6, defined therein for slidably receiving the column intermediate region 16. The carriage 40 also includes a transverse bore 44 which intersects bore 42 and a ball 46 is located within bore 44 and is biased to the right, FIG. 6, by spring 48 which engages the threaded plug 50 consisting of an Allen screw for rotation and axial positioning within the bore 44. The spring 48 biases the ball 46 to the right for selective engagement with the recesses 52 defined along the column at axially spaced locations wherein the recesses 52 define indices and the ball 46 constitutes an index for selectively locating the carriage 40 along the column.
An elongated guide 54 is bonded to the top of the carriage 40 having an opening through which the column extends. The guide 54 includes portions extending transversely from both sides of the carriage 40 and the column 10 and indicia 56, FIG. 3, is formed on the guide 54 to indicate the distance from the column 10.
Probes 58 and 58' are slidably mounted upon the lateral portions of the guide 54 and the probes 58 and 58' are identical mirror images of each other. Each of the probes includes an inner leg contact surface 60 or 60', and the inner ends are indicated at 62. A hole 64 is defined in the inner end of each of the probes wherein the indicia 56 formed on the guide 54 may be viewed therethrough, and a reference line 65 is formed on the probe inner ends 62 adjacent the holes 64 so that the position of the probes on the guide 54 may be accurately determined.
The probes are mounted upon the guide 54 by a slide 66, FIG. 5, which includes a U shaped recess 68 closely, but slidably, receiving the guide 54, and screws 70 attach the slide 66 to the probe inner ends 62. In this manner the probes 58 and 58' may be moved in a transverse manner relative to the column 10 and the position of the reference surfaces 60 and 60' from the center of the column 10 can be accurately determined by reference to the indicia 56 to the reference lines 65.
Preferably, to improve visibility and appearance the blocks 24, carriage 40, guide 54, probes 58 and slides 66 are formed of transparent material, such as acrylic.
In use, the apparatus is located at the front part of the patient's leg 72 and the upper pad 18 is located at the upper thigh region and is mounted to the patient's leg by the strap 36 which passes about the lower torso and can be drawn snug by means of buckle 38. In a similar manner the lower pad 20 is located at the ankle 76 and the strap 36' passes around the patient's ankle and is drawn snug by the buckle 38'. The measurement device 22 will normally be located adjacent the patient's knee region 74 as illustrated in FIG. 2.
When the apparatus is mounted upon the patient's leg as shown in FIG. 2 the column 10 will be located in front of the leg and relatively parallel thereto thereby forming a reference line or standard. When installing the device to the leg the column 10 is located in line with leg center line as closely as possible. Once the measurement device is firmly affixed to the leg the technician will locate the carriage 40 upon the column 10 as desired so that the detant ball 46 will be received within a recess 52. The recesses are located upon the column at those locations wherein the most critical measurements are desired, i.e. at the center of the knee, and at predetermined locations above and below the knee centerline, and also at thigh and shin locations. Once the carriage 40 is located upon the column as desired the probes 58 and 58' are moved toward each other until the edges 60 and 60', respectively, engage the side of the leg, and at that time the technician will observe and record the position of each probe to the guide 54 as indicated by reference lines 65 to indicia 56. As the measurement apparatus 22 is moved up and down the leg, and measurements taken at each location, a very accurate record can be made of the patient's leg so that orthosis devices for the knee or leg can be accurately formed, and much of the trial and error fitting process presently utilized with orthosis fittings is eliminated.
The measurement device of the invention is lightweight, inexpensive, is readily usable by technicians of limited skill without discomfort to the patient, and yet, accurate measurements for permitting the fitting of leg and knee orthosis devices is achieved.
It is appreciated that various modifications to the inventive concepts may be apparent to those skilled in the art without departing from the purpose and scope of the invention. | Knee orthosis measurement apparatus for attaching to the leg including a linear column having measurement probes mounted thereon for engaging the leg. The probes are mounted upon a scale connected to the column whereby the position of the probes to the columns may be readily determined to compare the position of various locations of the leg to the column. | 0 |
FIELD OF THE INVENTION
This invention relates to a method for separating m-xylene from p-xylene or o-xylene using specific alcohols, either alone or admixed with certain organic compounds as the agent in extractive distillation.
DESCRIPTION OF PRIOR ART
Extractive distillation is the method of separating close boiling compounds or azeotropes by carrying out the distillation in a multi-plate rectification column in the presence of an added liquid or liquid mixture, said liquid(s) having a boiling point higher than the compounds being separated. The extractive agent is introduced near the top of the column and flows downward until it reaches the stillpot or reboiler. Its presence on each plate of the rectification column alters the relative volatility of the close boiling compounds in a direction to make the separation on each plate greater and thus require either fewer plates to effect the same separation or make possible a greater degree of separation with the same number of plates. When the compounds to be separated normally form an azeotrope, the proper agents will cause them to boil separately during the extractive distillation and this make possible a separation in a rectification column that cannot be done at all when no agent is present. The extractive agent should boil higher than any of the close boiling liquids being separated and not form minimum azeotropes with them. Usually the extractive agent is introduced a few plates from the top of the column to insure that none of the extractive agent is carried over with the lowest boiling component. This usually requires that the extractive agent boil twenty Celcius degrees or more higher than the lowest boiling component.
At the bottom of a continuous column, the less volatile components of the close boiling mixtures and the extractive agent are continuously removed from the column. The usual methods of separation of these two components are the use of another rectification column, cooling and phase separation or solvent extraction.
p-Xylene, B.P.=138.4° C. and m-xylene, B.P.=139.1° C. have a relative volatility of only 1.02 and are virtually impossible to separate by rectification. m-Xylene and o-xylene, B.P.=144.4° C. have a relative volatility of 1.12 and are difficult to separate by rectification. Extractive distillation would be an attractive method of effecting the separation of xylenes if agents can be found that (1) will enhance the relative volatility between the xylenes and (2) are easy to recover from the xylenes, that is, form no azeotrope with xylene and boil sufficiently above xylene to make the separation by rectification possible with only a few theoretical plates.
The advantage of using extractive distillation in this separation can be seen from the data shown in Table 1 below.
TABLE 1______________________________________Theoretical and Actual Plates Required vs. RelativeVolatility for Xylene SeparationRelative Theoretical Plates Required Actual PlatesVolatility At Total Reflux, 95% Purity Required, 75% Eff.______________________________________1.12 52 701.20 33 441.25 27 361.30 23 311.35 20 271.40 18 241.50 15 20______________________________________
The relative volatility of m-xylene to o-xylene is 1.12 and thus require 52 theoretical plates for separation by conventional rectification at total reflux. Plates possessing an efficiency of 75% are commonly employed and thus about 70 actual plates are required, clearly a difficult separation. Several of the agents that I have discovered yield a relative volatility of 1.50 which would reduce the plate requirement to only 20.
The relative volatility of p-xylene to m-xylene is only 1.02 making this separation impossible by rectification. If an extractive distillation agent can be found that would increase the relative volatility to 1.2, p-xylene could be separated from m-xylene by rectification in a column with only 44 actual plates.
Extractive distillation typically requires the addition of an equal amount to twice as much extractive agent as the m-xylene and o-xylene on each plate of the rectification column. The extractive agent should be heated to about the same temperature as the plate into which it is introduced. Thus extractive distillation imposes an additional heat requirement on the column as well as somewhat larger plates. However this is less than the increase occasioned by the additional agents required if the separation is done by azeotropic distillation. Another consideration in the selection of the extractive distillation agent is its recovery from the bottoms product. The usual method is by rectification in another column. In order to keep the cost of this operation to a minimum, an appreciable boiling point difference between the compound being separated and the extractive agent is desirable. It is desirable that the extractive agent be miscible with o-xylene otherwise it will form a two-phase azeotrope with the o-xylene in the recovery column and some other method of separation will have to be employed.
Previous work on the separation of m-xylene from o-xylene by extractive distillation has been reported by Berg et al. U.S. Pat. No. 4,488,937 described the use of sulfolane; U.S. Pat. No. 4,585,526 used ether-alcohols; U.S. Pat. No. 4,673,465 employed polychloro compounds; U.S. Pat. No. 4,676,872 described adiponitrile; U.S. Pat. No. 4,676,875 reported dimethylformamide and U.S. Pat. No. 4,738,755 used benzoates. None of the agents described in the above five patents were effective in enhancing the relative volatility of p-xylene from m-xylene.
OBJECTIVE OF THE INVENTION
The objects of this invention are to provide a process or method of extractive distillation that will enhance the relative volatility of p-xylene to m-xylene and m-xylene to o-xylene in their separation in a rectification column. It is a further object of this invention to identify compounds that are stable, can be separated from xylenes by rectification with relative few plates and can be recycled to the extractive distillation column with little decomposition.
SUMMARY OF THE INVENTION
The objects of the invention are provided by a process for the separation of m-xylene from o-xylene and p-xylene from m-xylene which entails the use of certain alcohols, either alone or admixed with specific organic compounds as the agent in extractive distillation.
DETAILED DESCRIPTION OF THE INVENTION
I have discovered that certain alcohols, either alone or admixed with other specific organic compounds, will effectively increase the relative volatility between m-xylene and o-xylene or p-xylene from m-xylene and permit the separation of m-xylene from o-xylene or p-xylene from m-xylene when employed as the agent in extractive distillation. Table 2 lists the agents that I have found to be effective in the separation of m-xylene from o-xylene. The data in Table 2 was obtained in a vapor-liquid equilibrium still. The alcohols which are effective are, 1-decanol, diisobutyl carbinol, 1-octanol, 2-octanol, 1-nonanol, undecyl alcohol, isodecanol, isooctanol, isononyl alcohol 1-dodecanol and cyclododecanol. Table 2 also lists a number of non-alcoholic compounds which when mixed with cyclododecanol, gave effective relative volatilities but when used alone, were relatively ineffective. They are dimethylsulfoxide, methyl salicylate, ethyl salicylate, sulfolane, dimethylformamide, dimethylacetamide, acetophenone, nitrobenzene, diethylene glycol butyl ether, diethylene glycol ethyl ether and phenyl acetate. Table 3 lists a number of compounds which might be expected to be effective but were not either when used alone or when mixed with an effective alcohol.
Table 3 lists a number of compounds which might have been expected to act favorably with cyclododecanol in the separation of m-xylene from o-xylene but which failed to yield an effective relative volatility.
Pure cyclododecanol, whose relative volatility had been determined in the vapor-liquid equilibrium still was then evaluated in a glass perforated plate rectification column possessing 7.3 theoretical plates in the extractive distillation mode. It yielded a relative volatility of 1.31 after one hour and 1.37 after two hours of continuous operation. These data are listed in Table 4.
TABLE 2______________________________________Effective Agents For Separating m-Xylene From o-Xylene RelativeCompounds Volatility______________________________________Isodecanol (EXXON) 1.181-Decanol 1.21Diisobutyl carbinol 1.271-Octanol 1.382-Octanol 1.301-Nonanol 1.32Undecyl alcohol 1.40Isodecanol (ASHLAND) 1.27Isooctanol (U.C.) 1.27Isooctanol (EXXON) 1.24Isononyl alcohol (EXXON) 1.221-Dodecanol 1.31Cyclododecanol 1.37Cyclododecanol, Dimethylsulfoxide 1.32Cyclododecanol, Methyl salicylate 1.45Cyclododecanol, Ethyl salicylate 1.30Cyclododecanol, Dimethylformamide 1.34Cyclododecanol, Sulfolane l.38Cyclododecanol, Acetophenone 1.31Cyclododecanol, Dimethylacetamide 1.35Cyclododecanol, Nitrobenzene 1.33Cyclododecanol, Diethylene glycol butyl ether 1.42Cyclododecanol, Diethylene glycol ethyl ether 1.36Cyclododecanol, Phenyl acetate 1.33Cyclododecanol, Benzyl alcohol 1.30Cyclododecanol, 1-Decanol 1.37Cyclododecanol, 1-Octanol 1.36Cyclododecanol, Isodecanol (EXXON) 1.46Cyclododecanol, 2-Octanol 1.39Cyclododecanol, Diisobutyl carbinol 1.40Tridecyl alcohol 1.21Tridecanol 1.25______________________________________
TABLE 3______________________________________Ineffective Agents For Separating m-Xylene From o-XyleneWhen Mixed With Cyclododecanol RelativeCompounds Volatility______________________________________Methyl benzoate 1.0Benzonitrile 1.16Butyl butyrate 1.26Diethyl malonate 1.23Propylene carbonate 1.07Adiponitrile 1.212-Hydroxyacetophenone 1.212-Ethyl hexyl acetate 1.22Benzyl benzoate 1.0Diethylene glycol hexyl ether 0.72-Nitrotouene 1.25Diethylene glycol diethyl ether 1.24Ethylene glycol butyl ether acetate 1.1Propiophenone 0.8Phenethyl alcohol 1.292-Ethyl-1-hexanol 1.29Tridecyl alcohol 1.21______________________________________
TABLE 4______________________________________Data From Run Made In RectificationColumn - m-Xylene From o-Xylene Rela- Weight Weight tive Time % % Vol-Agent Column hrs. m-Xylene o-Xylene atility______________________________________Cyclododecanol Overhead 1 95.5 4.5 1.31 Bottoms 75 25" Overhead 2 96.5 3.5 1.37 Bottoms 73.6 26.4______________________________________
Table 5 lists the agents that I have found to be effective in the separation of p-xylene from m-xylene. The data in Table 5 was obtained in a vapor-liquid equilibrium still. The alcohols which are effective in bringing m-xylene out as the overhead from p-xylene are benzyl alcohol, diisobutyl carbinal, 1-dodecanol, 1-nonanol, undecyl alcohol, 1-decanol, isodecanol, tridecanol and tridecyl alcohol. Cyclododecanol brings out the p-xylene as overhead product. The compounds which when mixed with cyclododecanol enhance the relative volatility are benzonitrile, dimethylsulfoxide, dimethylacetamide, dimethylformamide, adiponitrile, diethylene glycol butyl ether, diethylene glycol diethyl ether, butoxypropanol, ethylene glycol butyl ether acetate, phenethyl alcohol, n-octanol, tetrahydrofurfuryl alcohol, propiophenone, benzyl alcohol, isodecyl alcohol and diisobutyl carbinol.
Table 6 lists a number of compounds which might have been expected to to act favorably as agents in the separation of p-xylene from m-xylene but which failed to yield an effective relative volatility.
A mixture comprising 75% cyclododecanol and 25% phenethyl alcohol, whose relative volatility had been determined in the vapor-liquid equilibrium still, was then evaluated in a glass perforated plate rectification column possessing 7.3 theoretical plates in the extractive distillation mode. It yielded a relative volatility of 1.28 after one hour and 1.33 after two hours of continuous operation. These data are listed in Table 7.
TABLE 5______________________________________Effective Agents For Separating p-Xylene From m-Xylene RelativeCompounds Volatility______________________________________Cyclododecanol, alone 1.11Cyclododecanol, Benzonitrile 1.16Cyclododecanol, Dimethylsulfoxide 1.14Cyclododecanol, Dimethylacetamide 1.24Cyclododecanol, Dimethylformamide 1.17Cyclododecanol, Adiponitrile 1.13Cyclododecanol, Diethylene glycol butyl ether 1.16Cyclododecanol, Diethylene glycol diethyl ether 1.41Cyclododecanol, Butoxypropanol 1.38*Cyclododecanol, Ethylene glycol butyl ether acetate 1.5*Cyclododecanol, Phenethyl alcohol 1.35Cyclododecanol, n-Octanol 2.3Cyclododecanol, Tetrahydro furfuryl alcohol 2.1*Cyclododecanol, Propiophenone 1.20Cyclododecanol, Benzyl alcohol 1.57Cyclododecanol, Isodecanol (EXXON) 1.63*Cyclododecanol, Diisobutyl carbinol 1.73*Benzyl alcohol 1.19*Isodecanol (EXXON) 1.21*Diisobutyl carbinol 1.23*1-Dodecanol 1.11*1-Nonanol 1.14*Undecyl alcohol 1.14*1-Decanol 1.21*Isodecanol 1.16*Tridecanol 1.30*Tridecyl alcohol 1.25*______________________________________ *Brings the mXylene out as overhead
TABLE 6______________________________________Ineffective Agents For Separating p-Xylene From m-Xylene______________________________________Butyl benzoate Benzyl benzoateButyl butyrate NitrobenzeneMethyl salicylate Diethylene glycol hexyl etherPropylene carbonate Diethylene glycol ethyl etherDiethyl malonate ButoxypropanolSulfolane Phenyl acetateAcetophenone 2-Octanol2-Hydroxyacetophenone 1-Octanol2-Ethyl hexyl acetate Tetrahydrofurfuryl alcoholIsooctyl alcohol Isononyl alcohol2-Ethyl-1-hexanol______________________________________
TABLE 7__________________________________________________________________________Data From Run Made In Rectification Column - p-Xylene From m-Xylene Time Weight % Weight % RelativeAgent Column hrs. p-Xyene m-Xylene Volatility__________________________________________________________________________75% Cyclododecanol, Overhead 1 93.8 6.2 1.2825% Phenethyl alcohol Bottoms 70.8 29.275% Cyclododecanol, Overhead 2 97.5 2.5 1.3325% Phenethyl alcohol Bottom 68.4 31.6__________________________________________________________________________
THE USEFULNESS OF THE INVENTION
The usefulness of this invention can be demonstrated by referring to the data presented in Tables 2 to 7. All of the successful agents show that m-xylene can be separated from m-xylene or p-xylene by means of extractive distillation in a rectification column and that the ease of separation as measured by relative volatility is considerable.
WORKING EXAMPLES
Example 1
Ten grams of m-xylene, 30 grams of o-xylene and 20 grams of cyclododecanol were charged to a vapor-liquid equilibrium still and refluxed for three hours. Analysis indicated a vapor composition of 29.8% m-xylene, 70.2% o-xylene; a liquid composition of 23.6% m-xylene, 76.4% o-xylene which is a relative volatility of 1.37.
Example 2
Ten grams of m-xylene, 30 grams of o-xylene, 20 grams of cyclododecanol and ten grams of diisobutyl carbinol were charged to the vapor-liquid equilibrium still and refluxed for 14 hours. Analysis indicated a vapor composition of 31.2% m-xylene, 68.8% o-xylene; a liquid composition of 24.5% m-xylene, 74.5% o-xylene which is a relative volatility of 1.40.
Example 3
225 grams of m-xylene and 75 grams of o-xylene were placed in the stillpot of a glass perforated plate rectification column containing 7.3 theoretical plates, and heated. When refluxing began, an extractive agent comprising cyclododecanol was pumped into the column at a rate of 15 ml/min. The temperature of the extractive agent as it entered the column was 95° C. After establishing the feed rate of the extractive agent, the heat input to the column was adjusted to give a total reflux rate of 40 ml/min. After one hour of operation, overhead and bottoms samples of approximately two ml. were collected and analysed by gas chromatography. The overhead analysis was 95.5% m-xylene, 4.5% o-xylene and the bottoms analysis was 75% m-xylene, 25% o-xylene. Using these compositions in the Fenske equation, with the number of theoretical plates in the column being 7.3, gave an average relative volatility of 1.31 for each theoretical plate. After a total of two hours of continuous operation, samples of overhead and bottoms were again taken and analysed. The overhead analysis was 96.5% m-xylene, 3.5% o-xylene; the bottoms analysis was 73.6% m-xylene, 26.4% o-xylene which is a relative volatility of 1.37. These data are listed in Table 4.
Example 4
Twenty grams of m-xylene, 60 grams of p-xylene, 30 grams of cyclododecanol and 15 grams of benzyl alcohol were charged to the vapor-liquid equilibrium still and refluxed for five hours. Analysis indicated a vapor composition of 86.9% p-xylene, 13.1% m-xylene; a liquid composition of 80.8% p-xylene, 19.2% m-xylene which is a relative volatility of p-xylene to m-xylene of 1.57.
Example 5
Twenty grams of m-xylene, 60 grams of p-xylene, 30 grams of cyclododecanol and 15 grams of diisobutyl carbinol were charged to the vapor-liquid equilibrium still and refluxed for four hours. Analysis indicated a vapor composition of 68.9% p-xylene, 31.1% m-xylene; a liquid composition of 79.3% p-xylene, 20.7% m-xylene which is a relative volatility of m-xylene to p-xylene of 1.73.
Example 6
A glass perforated plate rectification column was calibrated with m-xylene and o-xylene which possesses a relative volatility of 1.11 and found to have 7.3 theoretical plates. A solution comprising 225 grams of p-xylene and 75 grams of m-xylene was placed in the stillpot and heated. When refluxing began, an extractive agent comprising 75% cyclododecanol and 25% phenethyl alcohol was pumped into the column at a rate of 15 ml/min. The temperature of the extractive agent as it entered the column was 95° C. After establishing the feed rate of the extractive agent, the heat input to the p-xylene-o-xylene in the stillpot was adjusted to give a total reflux rate of 40 ml/min. After one hour of operation, the overhead and bottoms samples of approximately two ml. were collected and analysed by gas chromatography. The overhead analysis was 93.8% p-xylene, 6.2% m-xylene and the bottoms analysis was 70.8% p-xylene, 29.2% m-xylene. Using these compositions in the Fenske equation, with the number of theoretical plates in the column being 7.3, gave an average relative volatility of 1.28 for each theoretical plate. After two hours of continuous operation, samples of overhead and bottoms were again taken and analysed. The overhead analysis was 97.5% p-xylene, 2.5% m-xylene; the bottoms analysis was 68.4% p-xylene, 31.6% m-xylene which is a relative volatility of 1.33. These data are listed in Table 7. | m-Xylene is difficult to separate from p-xylene or o-xylene by conventional distillation or rectification because of the close proximity of their boiling points. m-Xylene can be readily separated from p-xylene or o-xylene by using extractive distillation in which the agent is an alcohol. Typical examples of effective agents are: for m-xylene from o-xylene, 1-octanol and cyclododecanol; for p-xylene from m-xylene, diisobutyl carbinol and cyclododecanolphenethyl alcohol mixture. | 2 |
The present invention relates to a card reading device for a self-service terminal and in particular for an automated teller machine (ATM) according to the preamble of claim 1 . Furthermore the invention relates to a self-service terminal equipped with the same and to a method for monitoring the same according to the preambles of the independent claims.
BACKGROUND OF THE INVENTION
Very often, the card reading devices in self-service terminals are a primary target for manipulation-attempts and skimming-attacks. This is because a user, attempting to use the self-service terminal that in particular can be an ATM, requires a banking-card that usually comprises a chip and/or a magnet strip on which card data including the personal customer and account access data are stored. Unfortunately, self-service terminals are becoming subject of manipulation by third persons who try to obtain these data in a criminal manner. Amongst other techniques they try to insert a spy-device into the card-slot of the card reading device in an inconspicuous manner, wherein this spy-device is capable to directly read out the magnetic strip or to attach to an internal interface (such as an USB-interface) of the card reading-device. This shall finally realize a readout of the banking-card data in order to make an illegal copy of the card. Moreover, skimming-attempts are known in which an alien card reader is attached to the card reading device as an unobtrusive superstructure, capable to e.g. send the read out card data via a radio transmission. If the frausdster is also capable to obtain the personal identification number (so-called PIN) of the card he/she can easily withdraw money from accompanying account. Moreover, skimming-attacks are known in which an internal interface directly simulates/pretends a card reading process and thus manipulates the software control of the self-service terminal or ATM.
Moreover, direct trapping of a card is another known attack scenario. Within this trapping scenario a superstructure is mounted in front of the card reading device to steal the card. This superstructure comprises a “Lebanese loop” extending towards the card reading device and being mounted directly behind the card insert slot and having a flap which only allows one way insertion of the card. Once a customer inserts a card, said card is captured and trapped by the Lebanese loop; the flap blocks the card from being ejected. By this behaviour of the apparatus the user believes his/her card that a (rightfully) withheld or retract of the card occurs. Then he/she consequently leaves the self-service terminal. In the following the frauder or deceiver takes the card together with the superstructure.
In order to detect card trapping, the process of card-retract has been modified in the prior art. The card is first retracted, then driven out and then retracted again by the card reading device. If this procedure is not possible in a perfect manner, i.e. ejecting a card is not possible, it can be assumed that a card theft has been attempted. However, this security procedure/approach increases the transaction time at the device.
It is also known to counteract such manipulation attempts of self-service terminals be using sensors. The German patent application DE 196 05 102 A1 discloses to use one or more infrared sensors for safeguard the self-service terminal, wherein the signals of these sensors are processed by an evaluator device to detect superstructures.
In the German patent application DE 10 2008 012 231 A1 a protection device is proposed that comprises a protection-shield-generator and a connected induction coil to create an electromagnetic protection shield that covers the electromagnetic fields which are created during (illegally) reading-out the card and therefore influence/interfere the functionality of the alien card reading device (spy-device) such that it fails to deliver useful data. To avoid that the deceiver may detect this protection device, the electromagnetic protection-field is generated with a special protection signal simulating a standard card-reading signal that only contains unuseful psuedo-data. However, this protection device can not be used to avoid or impede such skimming-attempts that are directly targeted to the interior of the card reading device and e.g. receive signals from an inserted spy-device or even from an interior data interface.
In this context there is also to mention the German patent application DE 10 2009 019 708 A1 which discloses to create a stray or noise field via permanent magnets that are moved by piezo-elements, in order to generate an induced magnetic alternating field which effectively interferes the skimming card reading device while reading-out the data. Furthermore the European patent application EP 1 394 728 A1 is cited in which supersonic sensors are disclosed to detect an attached superstructure to the self-service terminal. But also these solutions are not capable to avoid or impede skimming-attempts that occur in the interior of the card reading device.
In the US patent application US 2006/0249574 A1 the misuse of a card is mentioned, but not a manipulation within the interior of the card reading device as such. Herein, it is proposed to equip the card with a microcontroller and an encryption function (cf. FIG. 2 ). For the power supply of the microcontroller there are photovoltaic or piezo-electric components proposed. However, monitoring of or defense against skimming-attempts via sensors is not described.
Furthermore, it is well known to protect devices that are commonly used to store money or valuables, in particular vaults or bank-vaults with sensors. For instance the German patent application DE 2 318 478 A1 discloses a monitoring system for a strongroom, in which supersonic-sensors are used to determine motions therein via the Doppler-effect. Another disclosure that is relying on an ultrasonic alarm mechanism is disclosed in the German patent application DE 2 617 467 A1.
Accordingly, conventional self-service terminals comprise a card reading device into which a card can be inserted that contains data to be read, wherein the self-service terminal comprises at least one sensor for defense against manipulation attempts and an evaluator device. However, these solutions are not capable for protection against manipulations attempts that aim on the interior of the card reading device.
Therefore, it the object of the present invention to further develop a card reading device as mentioned before in order to be capable to protect against manipulation attempts and skimming-attacks at the interior of the card reading device or at least make such attempts more difficult. Also a self-service terminal being equipped with such a card reading device and a method to monitor such a self-service terminal is provided.
SUMMARY OF THE INVENTION
The preceding object is achieved by a card reading device comprising the features of claim 1 as well as by a self-service terminal and a method having the features of the according juxtaposed claims.
Accordingly a card reading device is presented wherein at least one sensor system is attached in the card reading device and comprises at least one linearly extending sensor arrangement, wherein the evaluator device verifies at least one spatial dimension of the card via at least one sensor system. Hence, a card reading device is presented, in which a sensor system is directly arranged inside the card reading device but is particularly arranged in or at the intake compartment for the cards to be read, wherein the card reading device verifies at least one spatial dimension, in particular the length or width, via the sensor system. The sensor system can be e.g. an opto-electric sensor system.
The present invention also provides a self-service terminal that in particular can be an ATM, comprising said card reading device. Furthermore, a method for monitoring the self-service terminal or the ATM via the sensor system and the evaluator device is presented, wherein the sensor system is arranged inside the card reading device and comprises at least one linearly extending sensor arrangement that particularly is arranged in the intake compartment and wherein at least one spatial dimension of the card is verified/checked via the evaluator device.
Consequently, a sensor system is installed inside the card reading device to compare the spatial dimensions of an inserted object to that of a conventional card, such that it can be effectively determined, whether a conventional card is present in the card reading device or an alienated object, e.g. a spy-device with similar dimensions as compared to the card.
Preferred embodiments can be found in the dependent claims.
In a preferred embodiment the sensor system is arranged as a sensor arrangement comprising a plurality of linearly arranged sensor elements, wherein the sensor arrangement extends in a vertical or a horizontal direction relative to the inserted card. Herein, a first sensor arrangement can detect the length of the card as a first spatial dimension and/or a second sensor arrangement can detect the width of the card as a second spatial dimension.
In another preferred embodiment only one sensor arrangement is present to detect the width and length. The second sensor arrangement can for instance be arranged to not only detect the width of the card but also the length of the card by determining the beginning and the end of the card and by operating the evaluating device to measure the insertion time and thus to determine the length of the card according to a constant insertion velocity.
Therefore, the sensor system installed in the card reading device is particularly a sensor arrangement with a plurality of sensor elements that are linearly arranged and extend in a horizontal or a vertical direction of the card that has been inserted into the intake compartment. Herein, the first sensor arrangement detects the length of the card as the first spatial dimension and/or the second sensor arrangement detects the width of the card as the second spatial dimension. Moreover, an additional sensor or sensor system can be arranged within the card reading device that detects the height of the card as a third dimension. Preferably the sensor elements of the at least one sensor arrangement and/or the additional sensor system are embodied as opto-electric sensor elements. However, other sensor types can be employed as an alternative to detect the spatial dimensions of the card.
Moreover, a further additional sensor arrangement, in particular an opto-electric sensor system, can be arranged in the card reading device within the vicinity of the surface of the card to verify material properties of the card by discrete spectroscopy in particular.
Moreover, an additional sensor or sensor system can be arranged at the card-feeding-portion but particular at the retraction compartment for cards to be withheld, wherein that sensor can particularly be a light barrier that is connected with the at least one evaluator device and in particular comprises one or more opto-electric sensor elements to detect manipulations at the card-feeding-portion. In a preferred embodiment the card reading device can thus be arranged such that a further sensor system is arranged in the card-feeding-portion, wherein that sensor system is connected with the card reading device and comprises one or more sensor elements to detect manipulations at the card-feeding-portion. Also the sensor elements preferably are opto-electric elements of a light barrier but can be other components or sensor types to monitor the area.
The card reading device that usually comprises an intake compartment into which the card is inserted/fed can be configured to comprise at least one evaluator device with mechatronic transducers but in particular with piezo-electric transducers comprising sensors and/or actuators. The mechatronic transducers are arranged in the intake compartment to check/verify the integrity of the card reading device, but in particular of the housing and/or the intake compartment, wherein the evaluator device is arranged to receive a signal that has been excited from a portion of the mechatronic transducers and is detected by another portion of the mechatronic transducers to compare it with reference data, and to send out a warning signal at a defined deviation that stands for a lack of integrity of the card reading device. Therefore, mechatronic transducers can be arranged in or at the intake compartment, wherein said transducers can in particular be piezo-electric transducers, comprising sensors and/or actuators connected with the evaluator device. Said transducers are used to cause a vibration being applied to the card reading device, wherein the vibration is in the hearable sonic-range or eigenfrequency-range to check the integrity of the card reading device and in particular of the housing and/or the intake compartment. To this end the evaluator device manages reference data, e.g. reference data from a mechatronic transducer, that represents an acceptable condition of the intake compartment. The mechatronic transducers can also be arranged in a sensor patch or array. Herein, the sensor patch preferably comprises multiple sonic-electric and in particular piezo-electric sensor elements. Such a sensor patch can also be attached in the intake compartment of the card reading device but preferably parallel to a surface of the card to also check the material properties of the card. Herein, single components of the sensor patch can function as actuators but in particular piezo-electric actuators to excite a part of the card reading device or the card to vibrate, such that the other sensor elements of the sensor patch can generate the signals to be evaluated. Therefore, the evaluator device can be extended to not only evaluate signals coming from the opto-electric sensor patch but also signals coming from the other sensor elements in particular those from the mechatronic sensor arrangement.
DESCRIPTION OF THE FIGURES
In the following the present invention is described in accordance with embodiments and the attached figures which show the following representations:
FIG. 1 a shows a cross-sectional view of an installation of the card reading device;
FIG. 1 b shows a three dimensional view of the card reading device to be installed within a self-service terminal;
FIG. 2 shows a schematic view of an arrangement of sensor patches to verify the dimensions (length, width, height) of a card;
FIGS. 3,5 show diagrams of a signal pre-evaluation that are executed in the method;
FIGS. 4 a - c show logical connections between the steps of the method; a=inserting the card, b=retracting the card, c=checking/verifying the housing integrity;
FIGS. 6 a & b show a content extraction and classification obtained with the method;
FIG. 7 shows a schematic view demonstrating the function of a classificator able to learn;
FIG. 8 shows the function of a fuzzy-pattern classificatory;
FIG. 9 shows the process of an exemplatory method.
DETAILED DESCRIPTION
FIGS. 1 a and 1 b show a schematical view of the card reading device 20 comprising an intake compartment 13 for a card to be read. The intake compartment 13 also comprises the card reader or card reading elements as such, that for instance comprise a contact area/pad for reading card chips and a reading head/pick-up to read magnetic strips. The card 11 or 11 ′ to be read is supplied to the intake compartment 13 via the inserting slot by conventional means to be optimally positioned with respect to the card reading elements for reading. For this purpose conventional guiding and supply elements can be used.
In the present invention “card reading device” refers to the device as a whole (cf. FIG. 1 b ) thus comprising the housing 1 , a base plate 2 , a card reader 3 , in some cases a so-called IDKG-add-on 5 , additional sensors 6 , in particular light sensors or sensor arrangements, and optionally a camera 10 , and card-supply/transportation means. Depending on the actual version it is also possible that the device comprises less components. The term “card reader” refers to the device 3 that is used for the actual reading of the card. The housing 1 circumferences the card reader 3 in connection with the base plate 2 completely. Preferably, the transducer elements (mechatronic transducers) are mounted at/in the housing 1 ; but basically a mounting at all other single components is possible, too. For this purpose it is useful to consider a superposition of the modal stretchings (functions of strain) in the frequency ranges to be considered. By doing so significant and therefore suitable positions can be visualized and a positioning can be done.
The sole openings of the housing are represented by the opening area for insertion of the card (IDKG-slot unit/module 5 ) comprising the detection (unit) including the sensors 6 and by the opening for retraction of cards being monitored by the light barrier 7 .
As is shown in particular in FIG. 1 b , the card reading device 20 comprises a retraction compartment 8 in its rear area that is intended for storing/withholding cards 11 which the self-service terminal, due to have not met specific conditions, cannot give back to the user. The compartment 8 which is referred to as retraction compartment is located at the end of the supply/transport chain, meaning even behind the intake compartment 13 in which the specific card is read. After reading or attempting to read the card 11 , said card is transported further to the retraction compartment 8 .
The card reading device 20 is equipped with a sensor system (cf FIG. 2 ) that is mounted to a sensor carrier (cf FIG. 1A ) and can exactly detect and check the spatial dimensions (length, width and optionally height) of the inserted card 11 . Optionally a material determination via discrete spectroscopy in the IR-range can be performed by means of the sensor system.
The sensor system is arranged such that at least one dimension can be captured/detected that is preferably the width b or the length l or optionally the height h of the card. The sensor system 6 B measures the width b of the card but can also be used to measure the length l of the card, e.g. by a temporally triggered capturing by the sensor 6 B, wherein the length of the card is determined via the intake velocity/intake time. Moreover, single sensors can be used for each dimension. Said sensors can particularly be sensor arrangements such as opto-electric sensor arrays or strips of the type TSL208R that are fabricated by the company TAOS and comprise a number of 512 photodiodes linearly arranged in a distance of 125 μm. Herewith a very precise measurement can be achieved. Furthermore, an additional sensor 6 C can be arranged within the card reader or the intake compartment 13 to measure or check the height of the card (in z-direction). Depending on the specific case it can be sufficient to measure only one or two dimensions that are preferably the length and/or the width.
By means of the integrated sensor systems 6 A, 6 B and/or 6 C (optional) as well as by means of the light barrier 7 in combination with connection with the signal to retract coming from the card reader 3 the slots of the housing can be secured. Additionally an installed camera 10 (cf FIG. 1 b ) can be used. The functional connections are explained according to the FIGS. 4 a - c.
First of all it is referred to the FIG. 4 a that shows the verification of the inserted card 11 , wherein said verification/check is executed with the opto-electric sensor arrangement. In FIG. 4 a there are functional blocks A 1 -A 12 that represent the following:
A 1 : The opto-electric sensor elements provide/generate measurement signals for a width b, a length l and optionally for the height of the card 11 . A 2 : The evaluator device/electronics 4 checks/verifies the measured data/values comparing said values with standardized values of normalized banking cards. A 3 : If the measured values match/correlate to the standardized values the banking card is supposed to be a normal one. A 4 : Exciting via the piezo-electric sensor arrangement field 6 D is preferably not done during operation of the card reader. A 5 : However, monitoring of the card readers is executed, in particular of the card reader signals and/or energy consumption of the card reader. A 6 : If the measured data, as determined in A 2 , do not correlate to the standardized values, this indicates that an manipulation attempt has occurred. A 7 : Shutting down the card reader, and retracting the manipulated card if possible. A 8 : The software control of the delf-service terminal, which can be a PC, provides a warning signal. A 9 : An excitation can be executed at determined times of operation to verify the integrity of the housing. A 10 : An optional camera surveillance (cf 10 in FIG. 1 a ) can generate signals (images, video and/or audio). A 11 : The camera-signals are sent to the evaluator device 19 or to the computer in order to document the manipulation attempt and to store images of suspicious individuals for a subsequent identification. A 12 : Optional step wherein it is indicated/signaled that block/step A 9 is executed if this is allowed by the card reader data/signals.
FIG. 4 b is about monitoring the retract compartment via the sensor system or light barrier 7 (cf FIG. 1 a ) installed therein. In FIG. 4 b there are functional blocks A 1 -A 12 that display the following:
B 1 : The opto-electric sensor system or light barrier 7 at the retract slot creates signals, if a card 11 , a fake card or another object is transported through this slot or if an alien object is attempted to be inserted trought the compartment 8 from behind. B 2 : The evaluator device compares the result to the status of the card reader, meaning that the result is ‘okay’ if there is a retract situation. All other results are considered to be manipulation attempts. B 3 : Depending on the signals and measuring values it is determined that a normal card has been transported/supplied trough the retract slot 7 or that a normal retract process has happened. B 6 : If the transport of an abnormal card trough the retract slot 7 or the absence of a normal retract procedure has been determined in block/step B 2 , this indicates that there is a manipulation attempt. B 7 : The card reader is the shut down/switched off.
FIG. 4 c refers to a verification of the integrity of the card reading unit. The functional principle shown in blocks/steps CI-CVII however refers to a material-check of the self-service terminal housing to determine if it has been manipulated. FIG. 4 c refers to the verification of the housing (cf 1 in FIG. 1 b ):
CI: The evaluator device 4 triggers the verification/check of the housing by exciting piezo-electric actuators that are mounted at the housing to vibrate and by evaluating the measured values coming from same wise mounted sensor arrangements. The actuators can be integrated within the sensor arrangements (comparable to 6 D in FIG. 1 b ) or can be single piezo-electric elements of a certain field/area that are controlled to vibrate. CII: First of all the piezo-electric actuators are excited at known frequencies by a sweep. CIII: The sensors capture the signals. CIV: The evaluator device evaluates via the described method. CV: If the integrity of the housing is verified, the cycle starts from CI. CVI: If the integrity of the housing is not verified, the card reader will be switched off. CVII: The card reader will be switched off; where required even the whole self-service terminal.
The verification of the housing can also be a part of the disclosed method or can be an independent solution. If it is an independent solution, there are mechatronic transducers installed at or in the card reading device, in particular piezo-electric transducers, comprising sensors and/or actuators connected to the evaluator device. These transducers serve to generate a vibration that preferably lies in the audible range of eigenfrequency range on the card reading device but in particular on the housing. The mechatronic transducers are arranged in such a way in, on or at the card reading device that the integrity of the card reading device can be checked/verified. The evaluator device is arranged to receive a signal from the mechatronic transducers that has been excited by a part of the mechatronic transducers and is detected by another part of the mechatronic transducers to be compared with reference data and to output a warning signal, if a defined deviation is present implying a loss of integrity of the card reading device.
In the following the verification of the card material via the piezo-electric or optical sensor arrangement 6 D (cf FIG. 2 ) that is installed in the card reader is described in detail. This solution can also be embodied/executed as an independent solution, but is described as a part of the disclosed method in the present description according to FIG. 2 and FIGS. 5-9 :
To verify the integrity of the housing 1 of the card reading device, the card material and/or the intake compartment for the card 11 , the measurement signals coming from the sensor arrangements 6 D are pre-processed in the evaluator device 4 . This procedure is done in steps 121 - 128 and is explained according to the FIGS. 3 and 5 :
At first, in step 121 the local extrema for a specific incoming signal (starting point E) are determined, i.e. the absolute and relative maxima and minima of the amplitude from the signal waveform during the process. Then the upper and lower envelope is constructed in step 122 , wherein said envelopes being the an upper curve/function connecting the maxima and an lower curve/function connecting the minima. Then, in step 123 , an mean value of said envelope is formed, preferably as an arithmetic (or alternative) mean value. In a further step 124 a possible intrinsic modal-function (also known as IMF) is extracted. The steps 121 - 124 are executed in an iterative way, wherein in step 125 it is checked if and how severe the difference of two consecutive iteration-steps is. Therefore, the intensity of the deviation of two IMFs is checked.
If said difference/deviation is larger that a certain threshold, the next iteration step is performed (steps 121 - 124 ). Otherwise the latest determined IMF is used (step 126 ). Furthermore, the residuum is extracted in step 127 and is consecutively compared to a threshold in step 128 . If said residuum is larger than the threshold, a further iterative step is performed (steps 121 - 124 ). Otherwise the procedure is stopped (end point A=“stop”). In this case the IMF us used which was found suitable in step 126 .
The process displayed in FIGS. 3 and 5 displays an empirical mode decomposition (EMD) with which the piezo-electrical sensor signals can be processed to accordingly obtain one or more suitable IMFs being particularly characteristic for the material-properties of the investigated card. The executed EMD correlates to an iterative filtering process or smoothing process, wherein the highest frequency components can be extracted in each step. Thereby superpositions at high frequencies can be eliminated and amplitudes can be effectively smoothed. By using the EMD characteristic features can be yielded in a multidimensional feature space thus allowing an effective and reliable classification.
The data of the IMF as comprised in the process 120 can be subject to further steps including a classification that allows a solid decision of whether a manipulated card or even an alien body has been inserted into the card reader or not.
First of all it must be noted that the following has to be considered while using the features represented by the IMF:
Features are used to differentiate certain states. Features should be derived from possible object features. Features shall be different from one another (cf FIG. 6 b case (i) and (iii)). Objects of the same class should be found at similar locations in the feature space (cf cluster points such as shown in FIG. 6 s ). The lesser the number of features needed, the more effective the decision can be made. Generating good features shall be done specifically for each use case.
The yielded IMFs do basically represent a statistic pool of features (cf FIG. 9 ) that is particularly characterized by the following parameters of each of the specific IMF, namely by the standard deviation σ, the loop C, the excess E, the average deviation from the Median MD as well as the Median MAD of the total deviation. These data (amongst others) are particularly useful for a classification using a modified fuzzy-pattern classifier (MFPC) that is described according to FIGS. 7-9 :
It must be noted first, that IMF as yielded from the signal pre-processing (step 120 in FIG. 5 ) can optionally be subject to segmentation and to a subsequent feature extraction. However, these steps of the method are not explained in detail since the key aspect of the present application lies in the classification.
For classification a classification unit KFE (cf FIG. 7 ) is used that treats the data DAT (here the data of the specific IMF) as obtained according to a classificator KF as verification data PDAT and compares said data to a pattern mapping MZ. The classificator KF is not static therein but can be learned or optimized via a learning unit LE. This is done by treating the data DAT as training data TDAT and by comparing it to a pattern mapping MZ. The optimized classification KF is then employed to the real measured data (PDAT).
As shown in FIG. 8 the classificator is conditioned/defined as a fuzzy-pattern-classificator (FPK) to allow a fuzzy-pattern-classification. Such a classification describes a problem associated evaluation and assignment of data in the context of being gradually associated (association function μ(x)) and being coupled amongst each other according to measuring values (aggregation). By expertise and training (see FIG. 7 ) association functions can be generated according to measurements. The fuzzy-pattern-classification takes into account the uncertainty of the classes being generated from single observations and employs the concept of association functions. The association function μKL: X→[0,1] correlates every object x of the feature space X to a number from the real valued interval [0,1], wherein this number designates the degree of belonging μKL(x) of the object to the un-sharp class KL. Furthermore, an uncertainty of every sole observation or every object due to methodological problems, measurement errors and so on is assumed. This uncertainty is expressed by designating an basic uncertainty to every object. For further details it referred to the literature.
The input for the fuzzy-pattern-classification, as displayed in FIG. 7 , are statistical features as displayed in FIG. 9 .
The extracted features comprise for instance the standard deviation, skewness, kurtosis average deviation from the median and the median of the absolute deviation. The standard deviation is a measure for the shattering of the values of a random variable around its expectation value. The skewness is a statistical characteristic number describing the type and strength of the probability distribution. It designates how strong the distribution tends to the right (positive skewness) or to the left (negative skewness). The kurtosis is a measure for the peakedness vs. tailness of a (single maximum) probability distribution, statistical density distribution or frequency distribution. The kurtosis is the central moment of order four. Distributions with a small kurtosis are distributed relatively uniformly; distributions with a higher kurtosis correspond to events that are distributed more extreme but for less events.
The median or also called central value is a mean value of distributions in statistics. The median of a list of numbers is the value that stands in the middle of said list after sorting the numbers in said list according to their value. The mean absolute deviation from the median is the variation/spreading around the median. Spreading/scattering (also called dispersion or average absolute deviation) combines various characteristic numbers in descriptive statistics and stochastics that describe the scattering widths of values of a frequency distribution or probability distribution around a suitable location parameter. The described calculation methods differ in being affected or being sensitive against runaway values. The scattering of the frequency distribution is called the standard error.
For the determination of the class the method uses a special procedure of supervised learning from structured, fuzzy example objects, i.e. objects that are defined to belong to a class by a “teacher” or “expert”. Both the elementary fuzziness of objects and the fuzziness of the classes is expressed by the asymmetric potential-function according to Aizerman.
Summarizing and by considering all FIGS. 1-9 the following can be said to the implementation of the method in a self-service terminal:
Besides the installation of the opto-electric sensors for verifying the card dimension (sensor array 6 A and 6 B as well as 6 C in FIG. 1 a ) and the opto-electric and/or piezo-electric sensor arrangement 6 D for checking the card material and/or the condition of the intake compartment, the housing 1 of the self-service terminal (see FIG. 1 b ) can also comprise piezo-electric patches monitoring the manipulations at the housing itself. The housing can be made out of steel and/or plastic. It forms a base plate 2 and IDKG-module 5 enclosed in the housing. The only openings are the card slots for card intake and card retract (region 8 ). The piezo-electric are attached adherently in the preferred version, but can alternatively also be directly be formed in a plastic part. The sensors are operated by the evaluator electronic or evaluator device 4 . The sensors can be operated as actuators or sensors. To this end the evaluator device 4 excites one of the sensors in an actuator fashion in a pre-defined pattern and the other piezo-electric patches obtain the excited signal. The electronics then compares the signal to a theoretical signal.
Furthermore the Computer of the self-service terminal (e.g. an ATM) is physically connected to the electronics. The electronics powers the card reader and is also optionally connected to the electronics in a logical way. The first (meaning the physical connection) serves a defined switching on and off of the card reader, the latter (meaning the logical connection) is used for processing possible firmware-signals of the card-reader, such as a retract or intake of the card. If the signal output of the card reader does not yet have firmware implemented, the energy intake of the card reader can be measured thus giving a reasoning for the modus of operation (intake/retract/output(stand-by) of the card reader.
The retract area (see FIG. 1 b ) guides and centers the card 11 to the card reader 3 . It is equipped with said opto-electric sensor system being a sensor and light barriers that obtain the geometrical dimensions of the card completely. By means of at least one sensor arrangement, e.g. 6 B in FIG. 2 it can be distinguished between a regular valid card and a non valid object, e.g. being a device for installing a skimmer in the interior of the device. The signals of the sensor arrangements 6 A and/or 6 B as well as the additional sensor 6 C are evaluated in the evaluator device 4 . The same is valid for the light barrier at the retract acompartment. However, in this case the light barrier 7 is not qualitatively evaluated but a fusion of information with the event “retract” of the card reader. Furthermore, the evaluator device 4 can send signals to the computer that activates a the optional surveillance camera 10 by a software (e.g. OSG) and checks the integrity of the card reader slot.
LIST OF REFERENCE SIGNS
20 card reading device
1 housing
2 base plate
3 card reader
4 evaluator device
5 IDKG slot module
6 sensors
7 light barrier
8 retraction compartment
10 camera(s) (optional)
11 card (EC/Master/Visa) inserted
11 ′ card (EC/Master/Visa) in an insert slot
13 intake compartment
6 A, 6 B 6 B linearly extending sensor arrangement;
6 C additional sensor system
6 D sensor array with piezo-electric sensor elements
121 - 128 steps for signal pre-processing
A 1 -A 12 ; B 1 -B 7 ; CI-CVII functional blocks | A card reading device ( 20 ) for a self-service terminal has an intake compartment ( 13 ) for a card ( 11 ) containing data to be read. The intake compartment ( 13 ) has at least one linearly extending sensor arrangement ( 6 A, 6 B) and an evaluator device ( 4 ) connected thereto to protect the card reading device ( 20 ) against manipulation attempts. The evaluator device ( 4 ) checks at least one spatial dimension (l,b) of the card via the sensor arrangement ( 6 A, 6 B), namely a dimension in a first direction (X) or a second direction (Y) in relation to the card ( 11 ) retracted into the intake compartment ( 13 ). Thus, it can be determined effectively whether a retracted card is a genuine card or if a manipulation is present that targets the inside of the card reading device. | 6 |
BACKGROUND OF THE INVENTION
This application deals generally with a probe for establishing a temporary electrical test connection with a terminal or wire of a circuit. Typically, such a probe includes an insulated handle, a rod extending from the handle, and a lead on the handle which is in electrical contact with the rod and adapted to be connected to a test wire.
Electrical connection with the terminal or a connector may be accomplished by sliding the rod of the probe inside the connector until the rod is disposed against the terminal. Since the terminal is flat and the rod is cylindrical, only a minimal surface area of the rod contacts the terminal. As a result, electrical contact between the probe and the terminal is disadvantageously minimized.
Further, currently available probes are disadvantageous because the terminal projecting from the back of the handle is not protected from incidental contact with neighboring components as the probe is slid into the connector.
Another disadvantage of current test probes is their unnecessarily complex shape and structure. As a result, the manufacture is complicated and the cost is increased.
SUMMARY OF THE INVENTION
It is a general object of the present invention to provide a test probe which avoids the disadvantages of prior test probes while affording additional structural advantages.
Another object of the invention is to provide a test probe adapted to provide maximum electrical contact with the terminal.
Another object of the invention is to provide a test probe having a rod of minimal cross section so as to enable access to a terminal in a confined space.
Another object of the invention is to provide a test probe having a test lead protected from incidental contact with neighboring components.
Another object of the invention is to provide a probe which is inexpensive and easy to manufacture.
In summary, there is provided an electrical test probe comprising a handle and a rod including a free end and an opposite end secured in the handle, the rod including a longitudinally extending generally flat face, the rod being adapted to be disposed against an electrical terminal to be tested such that the flat side abuts the terminal, According to the invention, the handle includes a cavity in the end opposite the end securing the rod, the end of the rod secured in the handle residing in the cavity for connection to a test lead of a meter.
The invention consists of certain novel features and a combination of parts hereinafter fully described, illustrated in the accompany drawings, and particularly pointed out in the appended claims, it being understood that various changes in the details may be made without departing from the spirit, or sacrificing any of the advantages of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
For the purpose of facilitating an understanding of the invention, there is illustrated in the accompanying drawings a preferred embodiment thereof, from an inspection of which, when considered in connection with the following description, the invention, its construction and operation, and many of its advantages should be readily understood and appreciated,
FIG. 1 is a side-elevational view of a test probe, on an enlarged scale, embodying the features of the present invention;
FIG. 2 is a top-plan view of the test probe, with a portion of the rod therein broken away;
FIG. 3 is a cross-sectional view of the rod, taken along the line 3--3 of FIG. 1;
FIG. 4 is a cross-sectional view taken along the line 4--4 of FIG. 2;
FIG. 5 is an end view taken along the line 5--5 of FIG. 1;
FIG. 6 is a side-elevational view of the test probe in electrical connection with a terminal inside a connector, the connector being broken away and shown in partial cross-section;
FIG. 7 is a cross-sectional view taken along the line 7--7 of FIG. 6;
FIG. 8 is a top-plan view of a pair of probes in electrical connection with adjacent terminals inside the connector, the connector being broken away and shown in partial cross-section; and
FIG. 9 is a perspective view of the test probe connected to a test lead of a meter.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, and more particularly to FIGS. 1 and 2, there is depicted a test probe generally designated 20, constructed in accordance with the present invention. The probe 20 is adapted to make an electrical test connection into a connector 70 such as the automotive connector shown in FIG. 6.
The probe 20 comprises a handle 30 and a rod 50. The handle 30 includes a generally cylindrical body 31 made of non-conducting material- The body 31 has opposite ends 32 and 33 and an outer surface 34. The outer surface 34 includes a thumb-receiving flat portion 35 adjacent the end 32 and at an acute angle with respect to the longitudinal axis of the rod 50. Another finger can be positioned on the portion 36 of surface 34 which is opposite the portion 35. The rod 50 includes a free end 51 having a chamfered tip 52.
Referring to FIGS. 4 and 5, a generally semi-spherical cavity 37 extends from the end 33 into the body 31. The cavity 37 defines a circumferential lip 38 at the end 33. The rod 50 includes an end 53, opposite the free end 51, secured in the handle 31. The end 53 extends through the body 31 and terminates in a loop 54 residing in the cavity 37 for connection to a test lead 55 (FIG. 9) of a meter (not shown). Although the segment of the rod between segment 58 and loop 54 is shown as sinuous (FIG. 4) that segment could also be straight, but flattened on its sides, for example, to provide good retention by the body 31. The cavity 37 extends into the body 31 a depth sufficient to receive the entire loop 54.
Referring to FIGS. 1 and 3, the rod 50 includes a first segment 56 having a longitudinally extending flat face 57 and a second segment 58 of circular cross section extending from the first segment 56 and into the handle 30. The first segment 56 is substantially longer than the second segment 58. The rod 50 is preferably made of spring steel. The rod 50 is oriented and secured to the handle 30 such that the thumb-receiving portion 35 is directed oppositely to the flat face 57. The finger-receiving portion 36 and the flat face portion 57 of rod 50 (FIG. 3) face the same direction.
As shown in FIGS. 6 and 8, the probe 20 is adapted to establish an electrical connection into the connector 70. The connector 70 includes a plurality of terminal ports 73. A terminal 74 and a wire 75 connected thereto are disposed in each of the ports 73. The wire 75 extends through a flexible rubber connector seal 76 disposed in each of the ports 73. The wire 75 is comprised of a metal core surrounded by an insulation layer.
The electrical connection between the rod 50 and the terminal 74 is established as follows. The probe 20 is grasped by a user's hand such that the thumb is placed on the portion 35 and the index finger is placed on the portion 36. As a result of the predetermined orientation between the portions 35 and 36 and the flat face 57, the user is aware of the orientation of the face 57 with respect to the wire 75 without examining the rod 50. Thus, the probe 20 can easily be positioned such that the face 57 abuts the wire 75. The probe 20 is then slid inwardly between the seal 76 and along the wire 75, with the face 57 in contact therewith, until the rod 50 is disposed against the terminal 74 (FIG. 7). The test lead 55 is then coupled to the loop 54 (FIG. 9) so that resistance tests or the like may be performed.
The diameter of the handle 30 causes the displacement of the wire 75 during insertion, in turn causing the displacement the of terminal 74 towards the rod 50, to enhance the contact between the flat face 57 and the terminal 74. Further, the diameter of the handle 30 is such as to assure that the wire portion 50 of one probe does not contact the wire portion 50 of another probe 20 being used in an adjacent port 73 (FIG. 8).
Because the face 57 is flat, access to a terminal in a confined space is possible. Also, maximum surface-to-surface contact between the rod 50 and the terminal 74 occurs. The cross-sectional dimension of segment 56 is such as to minimize deformation, and thus damage, to the connector seal 76.
While a particular embodiment of this invention has been described, it is to be understood that changes can be made in such embodiment without departing from the spirit and scope of the invention as defined in the claims. | The test probe comprises a handle and a rod, the rod including a flat face which can be placed against an electrical terminal to be tested. The rod includes a loop residing in a cavity in the handle. An alligator clip may be applied to the loop. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This invention is a divisional of and claims the benefit of priority to U.S. Non-Provisional patent application Ser. No. 13/797,457, filed Mar. 12, 2013, which claims priority to U.S. Provisional Application Ser. No. 61/658,406 filed Jun. 11, 2012, both of which are incorporated therein by reference in their entirety.
FIELD OF INVENTION
This invention relates to diagnostic imaging, and in particular to systems, apparatus and methods for collecting, storing, and analyzing raw scan data as well as raw scan data processing and image reconstruction algorithms and software used for medical diagnostic imaging, non-destructive material analysis, security and other imaging applications.
BACKGROUND OF THE INVENTION
In the medical industry it is well known to use technologies such as computer tomography (CT), positron emission tomography (PET), magnetic resonance imaging (MRI), ultrasound, conventional X-rays and various other technologies to diagnose the health of a patient. The equipment used to provide such imaging is generally very complex and expensive. For CT imaging, the equipment generally includes a CT scanner that collects raw CT data and proprietary software that reconstructs 3D images out of raw data utilizing scanner's various hardware components, including computers. A computed tomography (CT) method uses X-ray scan data to reconstruct detailed images of a body's interior structure.
Despite the fact that only raw CT data preserves all the medical information acquired during a scan, in practice, only the image data (results of reconstruction) are saved. Once raw data is deleted there is no way back to perform additional image reconstructions without a repeat scan. But, if raw data were saved, radiologists will be able to request retrospective reconstructions to more precisely zero in on specific regions of interest (ROI) without a repeat scan.
In addition, raw data from previous scans can be used for better planning of new scans and much more accurate monitoring of the treatment/disease progress. Availability of raw scan data to a wider group of image reconstruction professionals will also stimulate faster development and adoption of the next generation of reconstruction technologies. The same data sets can be used for testing and improving other new image reconstruction methods.
The saved raw CT data can also be used to more accurately determine the source of a medical problem, optimize treatment or disease monitoring and lead to a paradigm shift in medical imaging, improving medical care not just on the individual patient level but on the entire patient population level.
FIG. 1 shows a conventional prior art workflow of CT data acquisition and image reconstruction using software pre-installed on a scanner.
Referring to FIG. 1 , the Scan Order 10 can be generated by a physician to assist with diagnosing or treating a medical issue or related issues. The scanner technician can perform a scan of a patient in accordance with the Scan Order 10 and certain scanner-specific pre-determined scan protocol. The protocol takes into account numerous patient-related variables to optimize diagnostic quality and minimize the amount of radiation exposure by the patient.
During the scan, the scanner 20 collects raw CT scan data, sufficient to perform a computed tomography (CT)-based 3D (three-dimensional) image reconstruction, and stores raw scan data temporarily on the scanner 20 which includes a computer with pre-installed data processing and reconstruction software and temporary CT data storage.
After the scan is complete, the processing and image reconstruction software preinstalled on the scanner 20 performs raw data processing followed by 3D image reconstruction.
The reconstructed 3D image volumes are temporarily stored on the scanner 20 and are also sent to the image repository called Picture Archiving and Communication System (PACS) 30 which also includes a computer for medium-term storage. The PACS 30 system as well as image visualization workstations connected to the PACS 30 can be accessed by physicians/radiologists to read and interpret the reconstructed images of a patient. Long-term storage (e.g., multiple years) of images can also be done.
Prior art exists in the area of image manipulation (or enhancement), which takes place after images have been reconstructed by the scanner system and raw data has been deleted. Such image-based image enhancement has inherent weakness over the raw data-based image reconstruction or raw data-based image enhancement. Many prior art patents in the area of imaging focus on specific algorithms for image manipulation rather than dealing with accumulation and re-inverting (re-imaging) of raw data acquired by a CT scanner/sensors to reconstruct a more accurate image of the body.
Various patents exist that touch on the idea of using previously generated images or downloading CT image data, but only in terms of using the data for their specific algorithm. See for example, U.S. Pat. No. 7,145,984 to Nishide et al.; 7,684I 589 to Nilsen et al.; U.S. Pat. Nos. 7,599,534 and 7,672,491 to Krishnan et al.; 7,7561 314 to Karau et al.; U.S. Pat. No. 7,860,286 to Wang and Jackson; U.S. Pat. No. 8,195,481 to Backhaus; which are each incorporated by reference in their entirety.
Nishide et al. '984 describes a method to plan a scan in consideration of past patient exposures. The method includes a step of sampling information on a patient exposure the subject has received during a scan performed for reconstructing tomographic images, which is appended to each of the reconstructed tomographic images, on the basis of identification information with which the subject is identified; a step of creating a distribution of patient exposures calculated relative to an axis orthogonal to the scanning directions on the basis of the sampled information on the patient exposure (an estimated patient exposure, which is estimated in planning a scan, and an exposure limit); and a step of displaying the created exposure distribution.
The components 10 , 20 and 30 of FIG. 1 are generally covered in the above identified patents. Nilsen et al. '589 describes a technique to accelerate the image reconstruction process by dividing one set into subsets, where “The raw image data is decomposed into N subsets of raw image data. N is based on a number of available image generation computer processors. The N subsets of raw image data are processed to create processed image data. The image generation processors perform image processing on the image data in parallel with respect to each other.” This patent describes “a method for increasing the performance of a system for processing raw image data via dividing it into smaller subsets of raw image data.” This patent would also be potentially obsolete in the future based on continuing advances in efficiency of algorithms and computing power would make this technology unnecessary.
Krishnan et al. '534 and '491 are described as being used for “processing a medical image to automatically identify the anatomy and view from the medical image and automatically assess the diagnostic quality of the medical image. In one aspect a method for automated decision support for medical imaging includes obtaining image data, extracting feature data from the image data, and automatically performing anatomy identification, view identification and/or determining a diagnostic quality of the image data, using the extracted feature data.” The methods described here are generally using an Image Database for performing feature analysis, anatomy/view identification and quality assessment of the imaged data (images) but not with raw CT data.
Karau et al. '314 is designed for dealing with imaged data for acquiring images on an imaging system and performing accessing image data with a Computer-Aided Design (CAD) algorithm.
Wang et al. '286 describes a medical image acquisition error detection technique which uses special characteristics of medical images to detect possible errors. In general, the presented technique categorizes medical images based on the type of images. When a medical image is to be examined for possible acquisition errors, it is categorized and a measure of difference between the image and the standard image for the category is computed. If the measure of difference falls outside the acceptable difference for the category, the image is deemed to contain an acquisition error and an alert is issued.
Backhaus '481 describes a teleradiology image processing system to receive, process, and transmit radiology read requests and digital radiology image data. Here, a radiology processing system can include a series of processing components configured to receive digital radiology data from a medical provider, extract relevant information and radiology scan images from the digital radiology data, and initiate and control a workflow with a qualified remote radiologist who ultimately performs a read of the radiology scan images. Other techniques in this patent facilitate data processing within the image processing system in response to medical facility rules and preferences; translation or conversion of digital images to other formats; compilation of patient and medical facility data obtained from the digital radiology data into medical records or data stores; assignment of radiology studies within a teleradiology workflow in response to licensing and credentialing rules; and billing functions in response to completed reads by the remote radiologist.
Thus, the first key problem in the prior art workflows, including solutions currently utilized by the medical industry, is that the raw data are only temporarily stored on the scanner {i.e., a few days) or even deleted right after the image reconstruction process is finished.
Another problem of the current workflow is that the scanner operates like a “black box”, where no one except the scanner manufacturer has access to the raw scan data. As such, CT scanners are designed in such a way that it is impossible for anyone except the scanner manufacturer to take the raw data from the scanner to perform an additional image reconstruction with another, potentially superior or more customized, image reconstruction algorithm (software).
It is also impossible for third parties to independently install, potentially superior or more customized, image reconstruction software onto the scanner.
When there is a medical diagnosis needed to further scrutinize a particular target using computed tomography, because raw CT data has been deleted, there is no known reliable alternative which is not based on manipulation with images, but to repeat a CT scan, thereby exposing the patient to additional high doses of X-ray radiation. Not only is this re-image requirement detrimental to the health of the patient, but it requires additional costly system resources, medical personnel time, etc.
Moreover, a repeated scan is often performed on a different scanner, and the image reconstruction is often performed by different software than the one used after the first scan, and the reconstructed images are with different skills, experience, etc.
All these factors can accumulate and result in an inconsistency with the first result and even in an incorrect medical diagnosis. It would be much safer for a patient and more reliable from the medical point of view to resolve a possible issue by returning back to the saved raw data and perform CT reconstruction avoiding all or the majority of the factors mentioned above. On top of that, it would be greatly beneficial to the patients to have an option to perform a repeat reconstruction (of course, without a repeat scan) using the best available reconstruction software. This option is not available in the current art.
These problems not only result in radiation over-exposure of the patient population, but on a global level limit the full potential of medical imaging diagnostic quality and the pace of making available for doctors and patients novel imaging algorithms developed outside the walls of scanner manufacturer technology centers.
Solutions to the above problems are not contemplated by the scanner manufacturers or in the prior art.
Thus, the need exists for a new workflow and system that solve the above problems with the prior art.
SUMMARY OF INVENTION
A primary objective is to provide methods, systems, and apparatus for collecting, storing, and analyzing raw scan data for medical diagnostic imaging, non-destructive material analysis and security applications that can perform image reconstruction of an object even after raw scan data acquired during scanning of this object are deleted from the scanner after the image reconstruction step.
A secondary objective is to provide methods, systems, and apparatus for collecting, testing and storing raw scan data, processing and image reconstruction, and image interpretation algorithms and software for medical diagnostic imaging, non-destructive material analysis and security applications that can be use independently from the software preinstalled on a scanner by the manufacturer of the scanner.
A third objective is to provide systems, apparatus and methods for collecting, storing, and analyzing raw scan data for medical diagnostic imaging and other applications, where the scanner does not operate as a “black box”, where only the scanner manufacturer has access to the raw data.
A fourth objective is to provide systems, apparatus and methods for collecting, storing, and analyzing raw scan data for medical diagnostic imaging and other applications, which allows raw scan data from the scanner to be used for performing additional data processing, image reconstruction and interpretation steps with another, potentially superior or more customized, data processing, image reconstruction, and interpretation algorithms (software) developed by a third party.
A fifth objective is to provide systems, apparatus and methods for collecting, storing, and analyzing raw scan data for medical diagnostic imaging and other applications, which allows third parties to independently install, potentially superior or more customized data processing, image reconstruction and image interpretation software onto the scanner or connect a scanner with a third party server capable of performing data processing, image reconstruction, and image interpretation using raw CT data acquired by the scanner but using a third party software.
A sixth objective is to provide systems, apparatus and methods for collecting, storing, and analyzing raw scan data for medical diagnostic imaging and other applications, which allows for additional reconstructions needed to further scrutinize a particular target without exposing the patient to additional high doses of radiation by repeating a CT scan of a patient.
A seventh objective is to provide systems, apparatus and methods for collecting, storing, and analyzing raw scan data for medical diagnostic imaging and other applications, which allows for additional reconstructions needed to further scrutinize a particular target without requiring additional costly system resources such as additional CT scans.
A scanner-independent system for collecting and storing raw scan data of an object or objects and performing raw scan data processing, image reconstruction and reconstructed image interpretation can include a raw scan data transfer module located adjacent to at least one scanner, the raw scan data transfer module to transfer raw data from the at least one scanner onto a raw scan database system after scans are completed and a database for storing raw scan data in compressed or uncompressed formats sufficient for performing image reconstructions at any time after storing raw scan data, an uploading protocol for transferring raw scan data to the raw scan database from any scanner via data networks using a digital information transfer medium; and a data processing and image reconstruction and image interpretation system for providing image processing, image reconstruction and image interpretation from the raw scan data on any stored scan data set at any time.
The at least one scanner can be selected from at least one of: computed tomography (CT) scanner, magnetic resonance imaging (MRI) scanner, positron emission tomography (PET) scanner, an ultrasound scanner, and other types of scanners.
The system can further include the capability to receive via a digital transfer medium any number of additional image reconstruction orders to be performed on the raw scan data stored in the database, which allows the raw scan data to be processed and image reconstructed by the data processing and image reconstruction system to provide additional image reconstructed volumes therefrom, and results of image reconstruction are transferred to one or more external picture archiving and communication system (PACS) data management systems (PACS).
The scan order can be generated based on analysis performed on stored raw data sets on database system, further comprising performing a scan according to the recommended-by-the-system modified scan protocol, with images resulting from the image reconstruction transferred to an external picture archiving and communication system (PACS) data management system.
The raw scan database system can include software providing raw scan data compression and decompression, and computer and software providing capabilities for raw scan and image data storage locally, in a centralized global database, or using cloud computing on the Internet.
The data processing, image reconstruction, and image interpretation system can include software providing raw scan data processing and image reconstruction, software providing interpretation of reconstructed volumes from raw scan data and updating the global raw scan database system with such reconstructed volumes, and an artificial Intelligence software system generating a new scan protocol and optimized data interpretation workflow based on a submitted scan order and the available information on the subject of scan study in the raw scan database system. An example of application of an Artificial Intelligence-based system for improved healthcare is described in U.S. Pat. No. 8,396,804 to Dala et. al., which is incorporated by reference in its entirety.
The digital information transfer medium can be selected from at least one of: a WEB portal, DVD (digital video disc), CD (compact disc), portable drives, and other software carrier transfer medium.
A Software Bank system used with scan data processing, image reconstruction and image interpretation applications, can include a software development and trial system for any raw scan data processing, image reconstruction and interpretation software created by any developers, raw CT (computer tomography) data sets from the raw scan database system and testing procedures for performing trials of any scale of software candidates for the Software Bank, and a Web-enabled portal to apply for a software trial and transfer software modules to satisfy the qualification requirements of the Software Bank.
The software and trial system can include input and output data format standards required to be satisfied by any software applied for a trial, phantom data sets for initial test runs performed by an applicant, software generating a set of real raw scan data from the raw scan database to perform a trial, a queue trial system to manage a number of applicants, required computer power, and data storage volume, and software for an automatic assessment of quality and reliability of software tested during the trial.
Input and output data format standards includes but is not limited to a binary and DICOM formats. DICOM or Digital Imaging and Communications in Medicine is a standard for handling, storing, printing, and transmitting information in medical imaging. It includes a file format definition and a network communications protocol.
Phantom data sets for initial test runs includes but is not limited to only raw scan data of a selected medical phantom or phantoms of simple or human-body-type structures (scan objects).
Queue trial system, which is designed to optimize the use of CPU power and data storage of the trial system, includes but is not limited to a set of scripts automatically managing the trial system.
Software for automatic assessment of quality and reliability of imaging results includes but is not limited to software programs to compare images generated by a tested software program with the phantom structure, if it is tested on a phantom, or with the results of imaging generated by one or a number of previously tested and approved for medical use image software programs.
The software successfully passing through the software development and trial system can be uploaded to the Software Bank and then information about this software becomes available to any user worldwide via a Web-based system.
A method for collecting, storing, processing of raw scan data, and image reconstruction and interpretation used for medical diagnostic imaging for more than one scan order, can include the steps of ordering a scan of a patient with a scanner adapted for diagnosing or treating a medical issue, generating raw scan data collected by the scanner, generating a computer based three-dimensional (3D) reconstructed image using the raw collected data, transferring the reconstructed image to an external picture archiving and communication system (PACS), data management system for providing the reconstructed image, separately storing the raw scanned data generated by the scanner in a raw database storage system, transferring the raw scanned data from the raw database storage system to a data Processing, Image Reconstruction and Interpretation System (PIRIS) and reconstructing additional images at any time with the PIRIS, wherein the raw scanned data is able to be continuously used at later times without having to perform another patient scan.
The scanner type can be selected from at least one of: computed tomography (CT) scanner, magnetic resonance imaging (MRI) scanner, positron emission tomography (PET) scanner, an ultrasound scanner, and other imaging modalities allowing to retrieve raw scan data.
The method can include the steps of ordering a second scan for the same patient, transferring the second scan order to the raw CT (computer tomography) database system with a digital information transfer medium, transferring the raw scan data from the first scan order to the PIRIS, and generating a second image reconstruction order based on the raw scan data generated by the scanner from the first scan order, the second image reconstruction based on reconstructed volumes from the raw scan data, so that the second image reconstruction is sent to the external picture archiving and communication system (PACS) data management system.
The transfer medium being can be selected from at least one of: a WEB portal, DVD (digital video disc)1 CD (compact disc)1 portable drives, and other software carrier transfer medium,
The method can include the steps of providing software to the PIRIS from a software bank, for the image volumes to be reconstructed.
In a preferred embodiment that can use a CT scanner, the detector data are subjected to various preprocessing steps such as calibration, scatter correction, beam hardening correction, and the like before it can be used for image reconstruction. For the purposes of this patent application, the raw data (also referred to raw scan data or raw CT data) can mean data at any stage, i.e. before any preprocessing done and all the way up to the stage when all preprocessing is performed and the preprocessed data is ready to be used for image reconstruction.
Further objects and advantages of this invention will be apparent from the following detailed description of the presently preferred embodiments which are illustrated schematically in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
For a fuller understanding of the invention, reference should be made to the following detailed description, taken in connection with the accompanying drawings, in which:
FIG. 1 is a prior art workflow of CT data acquisition and image reconstruction with scanner pre-installed software.
FIG. 2 shows a scanner-independent, stand-alone workflow system providing raw CT scan data-based image reconstruction performed automatically in parallel with the scanner's system, without impacting the operational workflow of the scanner or scan protocol. Raw scan data are stored in the raw CT database system (ROBS) and processes are performed using software from the data Processing, Image Reconstruction and Interpretation System (PIRIS).
FIG. 3 shows a modified scanner-independent, stand-alone workflow system used in FIG. 2 that also allows a user to select software pre-installed on the data Processing, Image Reconstruction, and Interpretation System (PIRIS) to be ran in parallel with the scanner's system and without changing the conventional operational workflow of the scanner or scan protocol.
FIG. 4 shows a modified scanner-independent, stand-alone workflow system used in FIG. 3 that also allows a user to select software pre-installed on the data Processing, Image Reconstruction, and Interpretation System with a new scan protocol guiding scan performance.
FIG. 5 shows a modified scanner-independent, stand-alone workflow system used in FIG. 4 with an additional web-based option permitting the system administrator controlling the global raw CT scan database system and the Software Bank to test and then install new software onto the software bank. Selected software modules from the software bank can then also be installed onto the scanner. The word global throughout this patent application references that the corresponding database is connected to the Internet.
FIG. 6 shows a modified scanner-independent, stand-alone workflow system used in FIG. 5 additional web-based option permitting external users to consult with the global raw CT database system.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Before explaining the disclosed embodiments of the present invention in detail it is to be understood that the invention is not limited in its applications to the details of the particular arrangements shown since the invention is capable of other embodiments. Also, the terminology used herein is for the purpose of description and not of limitation.
A list of the components in the figures will now be described.
1. Workflow steps of prior art scan order ( 10 ), scanner ( 20 ) and data management ( 30 ).
10 . Scan order.
20 . Scanner with pre-installed data processing and image reconstruction software and a temporary CT data storage.
30 . Data Management—Picture Archiving and Communication System (PACS) or any other image visualization and/or storage platform.
100 . Automatic scanner-independent, stand-alone workflow system.
21 . Raw CT scan Data Transfer Module (DTM).
105 . Raw CT Data.
106 . Raw CT data compression software module.
110 . Raw CT Database System (RDBS).
111 . ROBS request and decompressed raw CT data.
120 . Data Processing, Image Reconstruction, and Image Interpretation System (PIRIS).
121 . Request to consult with database systems (RDBS) and/or upgrade them.
130 . Reconstructed Image Volumes.
200 . Workflow of Embodiment 100 with Additional Reconstruction Order without changing scan protocol.
210 . Reconstruction Order.
115 . Raw CT data decompression.
300 . Workflow of Embodiment 200 with Additional reconstruction order and/or changing scan protocol.
310 . Reconstruction order and/or protocol change.
400 . Workflow of Embodiment 300 Web upload steps.
112 . Global Raw CT Database System (GRDBS).
410 . CT system Web portal to upload data and software.
415 . Uploading of new raw CT data sets onto GRDBS.
417 . External special requests to consult with GRDBS.
420 . Software Trial and QC systems.
430 . Software Bank.
440 . Installation of a software module from the software bank onto a scanner.
500 . Workflow of Embodiment 400 permitting an external user to request consulting with the GRDBS (i.e., with the global database of raw CT data, processed CT data, and CT imaged data/images) created and constantly expanded using raw CT data from any number of CT scanners.
First Embodiment
FIG. 2 shows a scanner-independent, stand-alone workflow system 100 providing raw CT data image reconstruction in parallel and/or simultaneously with image reconstruction performed by the software preinstalled on the scanner, without impacting the operational workflow of the scanner or scan protocol.
Here, the workflow for raw CT Database System (RDBS) and Data Processing, Image Reconstruction, and Image Interpretation System (PIRIS) use alternative data processing and image reconstruction software modules installed on an external server. This workflow does not require changing a scan protocol and therefore does not require an additional order from a physician generally required in the prior art workflow system of FIG. 1 .
Raw CT data are transferred from the scanner 20 using the Data Transfer Module 21 , which provides wireless/wire-based data transfer from the CT scanner 20 to the ROBS 110 . During this step raw CT data can be compressed 106 to reduce storage space on the RDBS.
Referring to FIG. 2 , there can be the following steps required as described below.
In a first step (1a), Scan Order 10 , a physician orders a scan, which includes at least one of: computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET), ultrasound, and the like, and can be used to assist with diagnosing or treating a medical issue or related issues in a similar manner as referenced in the prior art.
The second step, (2a), includes Setup and Scan 20 . The Scan can be performed in accordance with the Scan Order (1a) and a scanner and scan-specific protocol. The scan-specific protocol is based on the initial Scan Order from the physician.
A third step, (3a), can occur in the Raw CT Database System 110 . Immediately after the scan is performed or at a later time, the raw CT data are transferred from the scanner 20 using the Data Transfer Module 21 . The raw data 105 , which includes scanner information, protocol of the scan, and other related patient and scan data acquired before and during the scan and sufficient to perform data processing and image reconstruction, can be automatically compressed ( 106 ) to reduce storage space on the RDBS 110 and transmitted to and stored on the Raw CT Database System (ROBS) 110 , which includes hardware and database management software for local and/or cloud-based storage and organization of Raw Data.
An example of a system that is partially similar to the “RAW CT DATABASE SYSTEM” 110 that includes the hardware and software for this computer system can be found in at least U.S. Pat. No. 7,436,924 B2 by Takahashi et al., which is incorporated by reference. The U.S. Pat. No. 7,436,924 B2 by Takahashi et al. does not contemplate using the data base for the purposes of giving access to the data to third parties, using the data for later reconstruction by other algorithms, for improving the quality of healthcare by means including but not limited by the monitoring of the treatment of the patient, reducing the number of repeat scans, and the like. Another difference between the present invention and patent U.S. Pat. No. 7,436,924 B2 by Takahashi et al. is connecting the database to the Software Bank that can be used for image reconstruction.
The RDBS (Raw CT Database System) 110 can include, but is not limited to, raw CT data sets, scanner information, de-identified patient information, unique RDBS patient ID to be used to retrieve past CT scans of the patient, other medical information and/or data required to perform image reconstruction at any time without needing any additional information from other sources of information. Raw scan data can be stored in the original uncompressed form or in compressed form. RDBS 110 can also store the original reconstructed volumes generated by pre-installed on the scanner image reconstruction software.
The above set of data and scan information can be fully sufficient and can be stored for an indefinite amount of time. It is assumed that RDBS 110 is being backed-up on a regular basis and access to the system is not allowed to any unauthorized personnel to preserve RDBS integrity and confidentiality.
For the purposes of subsequent use, the database 110 should provide a way to establish a connection between patients' data (for example: raw CT data, reconstructed images, and the like) stored in the database and the patients' personal identifying information. For example, each data set in the database can be given a unique identifying number, and a separate database may contain the collection of these identifying numbers and the corresponding patient personal data such as social security numbers.
The Raw Data 105 can be stored for any period of time, such as but not limited to 7 years or longer, if patients and/or hospitals made special requests and/or paid for an extended storing time.
A fourth step (4a) occurs in the Data Processing, Image Reconstruction, and Image Interpretation System (PIRIS) 120 . Raw CT Data 105 can be first compressed ( 106 ) and then stored or stored in uncompressed form in the RDBS ( 110 ) and then automatically uploaded to the PIRIS System 120 , and the required steps as per RDBS request 111 , including image reconstruction are performed, utilizing the software pre-installed on the PIRIS System 120 . As many data processing, image reconstruction, and data analysis and interpretation runs can be performed as needed, utilizing, for example, various image reconstruction algorithms and other relevant software and input data. If necessary, these runs can all be performed simultaneously. The software on the PIRIS System 120 is regularly updated, tested, and new software modules are added as needed and/or when become available.
An example of a system having some elements partially similar to “DATA PROCESSING, IMAGE RECON AND INTERPRETATION SYSTEM (PIRIS)” 120 can be found in at least U.S. Pat. No. 8,134,571 B2 to Krishnan et al., which is incorporated by reference in its entirety. The significant difference between the present invention and the U.S. Pat. No. 8,134,571 B2 to Krishnan et al. is that the latter is dealing with image processing only, whereas the present invention deals with image reconstruction from raw data. By image processing we mean the manipulation of images that are of diagnostic value by themselves.
Additional step (4b) is a continuation of step (4a) from FIG. 2 . A Data Interpretation component is added to the Image Reconstruction System 120 (collectively, “Data Processing, Image Reconstruction and Interpretation System, PIRIS”, 120 ), which can be consulted by the physician in step (1c) to provide data helpful for determining the type of software and protocol to be utilized for the particular patient as well as additional information that can be obtained by utilizing the Raw CT Database and the software on the Image Reconstruction and Interpretation System.
An example of a system that is partially similar to the PIRIS system 120 can be found in U.S. Patent: U.S. Pat. No. 7,436,924 B2 by Takahashi et al. which is incorporated by reference in its entirety. The U.S. Patent U.S. Pat. No. 7,436,924 B2 by Takahashi et al. does not contemplate using the data base for the purposes of giving access to the data to third parties, using the data for later reconstruction by other algorithms, for improving the quality of healthcare by means including but not limited by the monitoring of the treatment of the patient, reducing the number of repeat scans, and the like. Another difference between the present invention and U.S. Pat. No. 7,436,924 B2 by Takahashi et al. is connecting the database to the Software Bank that can be used for image reconstruction.
Raw CT Data Processing, Image Reconstruction, and Interpretation System (PIRIS) 120 can include but are not limited to various algorithms that can be utilized individually or according to a predetermined workflow. In order to be used in the course of medical care, and utilized by the PIRIS system, the individual software modules and workflows are assumed to be tested and passed the FDA and other relevant regulatory approval processes that might be required in the future. Some algorithms, which can be part of PIRIS, are described in the above referenced U.S. patents to at least U.S. Pat. No. 7,436,924 B2 by Takahashi et al. and U.S. Pat. No. 7,684,589 B2 by Nelsen et al., which are incorporated by reference in their entirety.
Other examples of algorithms which can be part of PIRIS are described in U.S. Pat. Nos. 5,539,800; 5,550,892; 5,717,211; 7,590,216 all to Katsevich which cover local tomography, which in their entirety are all incorporated by reference, and U.S. Published Patent Application 2012/0128265 to Silver et al. entitled: Method and System Utilizing Iterative Reconstruction with Adaptive Parameters for Computer Tomography (CT), which is also incorporated by reference in its entirety.
A fifth step (5a) is the storage and transmission of reconstructed images. The image volumes reconstructed in step (4a) are stored on the Raw CT Database System (RDBS) 110 , previously described, and are also transmitted to an image repository called Picture Archiving and Communication System (PACS) 30 and/or other visualization workstations or image storage media.
Reconstructed image volumes mean reconstructed 3D structure of an object under study for which a CT scan has been ordered and then raw CT scan data have been acquired and processed. Reconstructed image volumes allow evaluating the whole patient's body or a certain Region of Interest (ROI) of a patient.
The physician is notified immediately (via all possible electronic notifiers) that the images have been reconstructed and are ready to be viewed and analyzed. Electronic notifiers can include but are not limited to automatic email message, text message, telephone call, and the like.
Second Embodiment
FIG. 3 shows the scanner-independent, stand-alone workflow system 200 of FIG. 2 which allows a system user to select the software from the list of pre-installed on the PIRIS System 120 modules, previously described. Here, workflow for RDBS 110 and PIRIS System 120 can use data processing, image reconstruction and interpretation software modules installed on an external server computer.
This workflow does allow applying an alternative scan protocol simultaneously with the protocol utilizing a pre-installed on the scanner image reconstruction software and therefore it requires an additional order from a physician.
Referring to FIG. 3 , an additional step (1b) can occur in the Scan Order 10 . As a continuation of (1a) from FIG. 2 , a physician orders a scan (for example, CT, MRI, PET, ultrasound, and the like) to assist with diagnosing or treating a medical issue or related issues and orders specific software module(s) to be utilized in performing image reconstruction (without impacting the scanner's workflow). This additional Reconstruction Order (see left arrow 210 in FIG. 3 ) can be ordered at the time of the original scan or at any later date if the Raw Data are saved in the computer system of the Raw CT Database System.
Currently, doctors have to use the software that comes with the scanner, but by using the ROBS and PIRIS systems, physicians will have freedom to choose the best image reconstruction algorithm (software) available at the time of the scan.
Specific software modules can include but are not limited to for example, local tomography to one of the inventors of the subject invention. See for example, U.S. Pat. Nos. 5,539,800; 5,550,892; 5,717,211; 7,590,216 all to Katsevich which cover local tomography, which in their entirety are all incorporated by reference. See for example, U.S. Published Patent Application 2012/0128265 to Silver et al. entitled: Method and System Utilizing Iterative Reconstruction with Adaptive Parameters for Computer Tomography (CT), which is also incorporated by reference in its entirety.
Also, doctors will be able to request retrospective reconstructions to more precisely zero in on specific areas of interest without a repeat scan. Further, raw data from previous scans can be used for better planning of new scans and much more accurate monitoring of the treatment progress or disease development.
Third Embodiment
FIG. 4 shows a modified scanner-independent, stand-alone workflow system 300 used in FIG. 3 that allows a user to select software pre-installed on the computer of the PIRIS System 120 with a new scan protocol guiding scan performance.
Referring to FIG. 4 , workflow 300 for the raw CT Database System (RDBS) 110 and PIRIS system 120 uses alternative software installed on an external server and alters the scan protocol and consults with the data analysis expert system of PIRIS.
Additional step (1c) occurs in the Scan Order 10 as a continuation of step (1b) from FIG. 3 . Rather than selecting the software pre-installed on the scanner 20 and the related protocol (as shown and described in FIG. 2 and FIG. 3 ), the physician can elect to modify the scan protocol in accordance with medical requirements to assess patient's medical condition or a treatment and using the additional capability provided by the software in the Software Bank that is not provided by the software on the scanner.
The result can be that the scanner 20 does not perform image reconstruction or that the images reconstructed on the scanner 20 are not of diagnostic quality to investigate a particular medical condition or perform a detailed treatment analysis. The additional step outlined in FIG. 3 which include step (1b) can be applicable here as well.
An example of application of an alternative algorithm can be based on Local Tomography. See for example, U.S. Pat. Nos. 5,539,800; 5,550,892; 5,717,211 7,590,216 all to Katsevich which cover local tomography, which in their entirety are all incorporated by reference.
With superior edge detection, the alternative algorithm provides the potential for enhanced diagnostic accuracy and be applicable to many areas in the body including heart, brain, spine, liver, and lung. Disease detection should be enhanced because of the edge enhancement characteristics of the local tomography algorithm. Moreover, with the full implementation of collimator assisted local scanning, radiation dose can be significantly reduced. This is an example of additional capability that could be provided by software in the software bank. In other words, the physician can elect to use collimators knowing that there is a code in the software bank that can reconstruct a diagnostic-quality image from such a lower radiation CT data set.
Image reconstruction software can be run using CPU (central processing unit) or GPU (graphics processing unit) types of computer processors that are referenced in for example in U.S. Pat. No. 7,684,589 B2 to Nilsen et al.; U.S. Pat. No. 7,145,984 B2 to Nishide; and U.S. Pat. No. 8,314,796 to Pratx, et al; which are all incorporated by reference in their entirety.
Fourth Embodiment
FIG. 5 shows a modified scanner-independent, stand-alone workflow system 400 used in FIG. 4 with an additional web-based option 410 permitting the user to request a software trial 420 of new software and, if approved, it can be loaded onto the Software Bank 430 . Another additional web-based option 415 permitting an external user to upload raw CT data sets via a web portal 410 connected to the Global Raw CT Database System (GRDBS) 112 .
Here, the new workflow for global raw CT Database System and Image reconstruction systems 400 uses an alternative software installed on an external server computer. This workflow allows the alteration of a scan protocol via consulting with PIRIS and uses software from the Software Bank 430 . Referring to FIG. 5 , step 4c allows for the Data Processing, Image Reconstruction and Interpretation System 120 to be connected to a repository of software (“Software Bank”) 430 .
Software from the Software Bank 430 can be installed on the Data Processing, Image Reconstruction and Interpretation System (PIRIS) 120 as part of previously described step (1b) and step (1c) utilizing a Web portal 410 or by other electronic technique. Other electronic techniques can include but are not limited to software carrier media, e.g., DVD, portable drives, and the like.
Under additional step (6a) prior to being uploaded into the Software Bank 430 , software passes through trials utilizing the Raw Data 105 from the GRDBS 112 (collectively, “Software Trial System”) 420 .
Software from the Software Bank 430 can include but is not limited to local tomography, iterative reconstruction, and other data processing, 3D image reconstruction algorithms. Examples of Local Tomography-based and Iterative Reconstruction algorithms are referenced in, for example, in U.S. Pat. No. 7,590,216 B2, to Katsevich, and U.S. Published Patent Application 2012/0128265 to Silver et al. entitled: Method and System Utilizing Iterative Reconstruction With Adaptive Parameters For Computer Tomography (CT), respectively, which are all incorporated by reference in their entirety.
The software should be required to pass regulatory approval (for example, FDA U.S. Food and Drug Administration) as well as other quality control steps to ensure compliance with system's performance standards. Access to the Software Trial System can be obtained via a Web portal 410 or by other electronic techniques, such as but not limited to software carrier transfer medium, such as but not limited to, DVD (digital video disc), CD (compact disc), portable drives, and the like.
Quality control steps include but are not limited to software testing procedures using predetermined phantom and raw CT data sets from the GRDBS to satisfy pre-determined performance standards that can be based on but not limited to tests for speed and accuracy of data processing, image reconstruction and analysis software.
Alternatively, new software modules can be uploaded from the Software Bank and installed onto the scanner 440 .
Regulatory government approval can include but is not limited to FDA (U.S. Food and Drug Administration) approval, and other government approval and the like. The described above part of this embodiment, in which additional software is installed on the scanner, has the advantage of eliminating potential time delays associated with transferring data from the scanner to the database and then to the reconstruction engine.
An Artificial Intelligence (AI) system can also be a part of the computer GRDBS 112 , previously described. The AI system preselects the best algorithm based on the type of scan, patient data, and the like, and suggests to the radiologist what additional software might be needed in every particular case. For example, to minimize delay, the reconstruction engine might reconstruct different volumes prior to the physician ordering these reconstructions. Thus, if the physician wants to see several images, they will be instantaneously available. For example, if the AI system knows that the patient is overweight, this means that the CT data are noisier, and therefore the system will run an iterative reconstruction algorithm, which is more stable with respect to noise in the data. Another example of application of an Artificial Intelligence-based system for improved healthcare is described in U.S. Pat. No. 8,396,804 to Dala et. al., which is incorporated by reference in its entirety.
Fifth Embodiment
FIG. 6 shows a modified scanner-independent, stand-alone workflow system 500 used in FIG. 5 with an additional web-based option 417 permitting an external user to request consulting 112 with the GRDBS (i.e., with the global database of raw CT data, processed CT data, and CT imaged data/images) created and constantly expanded using raw CT data from any number of CT scanners.
Such a consulting with the GRDBS can be used, for example, in the regular course of medical care for improving of treatment, early detecting or predicting of diseases, improving and testing of new reconstruction and/or interpretation methods, selecting of the best method for a specific disease, and the like. To maintain image reconstruction consistency, and therefore providing a more reliable reply on a request from an external user, image reconstructions of a number of raw CT data sets from the
GRDBS, which are required to be performed to generate such a reply, can be based on the same (unique) image reconstruction algorithm. Imaging process can be based on a single-type of reconstruction algorithm (For example, a Filtered-Backprojection-type algorithm (FBP)). Examples of these algorithms can be found in at least U.S. U.S. Pat. Nos. 6,574,299; 6,771,733; 6,804,321; 6,898,264; 7,010,079; 7,197,105; 7,242,749 to Hsieh et al; U.S. Pat. Nos. 7,280,632; and 7,305,061 all to Dr. Katsevich and U.S. Pat. No. 7,242,749 to Hsieh et al, that are all incorporated by reference in their entirety.
Additionally image processing can be based on a joint/sequential application of reconstruction algorithms (e.g., Local Tomography and Iterative Reconstruction). See for example, U.S. Pat. Nos. 5,539,800; 5,550,892; 5,717,211; 7,590,216 all to Katsevich which cover local tomography, which are all incorporated by reference in their entirety. See for example, U.S. Published Patent Application 2012/0128265 to Silver et al. entitled: Method and System Utilizing Iterative Reconstruction With Adaptive Parameters For Computer Tomography (CT), which incorporated by reference in its' entirety.
To assess quality of reconstruction, a comparison of two or more reconstructed 3D images of an arbitrary property (not necessarily density, the other one is gradient-like density computed by local tomography, etc.) can be done using but not limited to digital manipulation with images, e.g., subtraction, division, calculation of derivative, integration, and the like.
The invention can include software for automatically assessing quality and performance of software tested during the trial.
Image quality can be defined as the absence of significant image artifacts, high spatial resolution, low noise level, and the like.
Performance can include but is not limited to computational efficiency (minimum computational operation steps to run through the software), CPU power, and the like. The fewer iterations, the more efficient is the software.
Quality of software is characterized by producing images with good quality, for example, good resolution and contrast, and the like, described above.
Performing a fast clinical trial of a new image reconstruction algorithm can be performed using the GRDBS and PIRIS systems.
Other embodiments of the invention are possible. For instance, the raw CT database can contain a module that converts raw data collected by scanners from different manufacturers in different formats into a universal format that can be easily read by all third-party software developers. The advantages of this module are manifold. The company that develops a conversion module can execute non-disclosure agreements with the CT manufacturers and get information about their raw data formats under the agreement. Thus, third-party developers will only be able to see the standard uniform format and the proprietary data formats of the CT manufacturers will not be compromised. Another advantage is that if the standard format is published and well-advertised, this will spur innovation since third-party developers will not have to worry about reading data in multiple formats from different CT manufacturers.
While most of image reconstruction is currently done in 3D, there can be some applications in which two-dimensional (2D) images are of interest. Thus, there can exist embodiments that deal with 2D and/or 3D image reconstruction. Similarly, imaging can be performed in (four dimensional) with time being the additional dimension, and so the database should also have capabilities for storing and processing of 4D data.
While normally one can expect a raw scan data transfer module to be located adjacent to at least one scanner, by utilizing an intranet of a hospital, one can get access to the raw data even if the transfer module is not located adjacent to any scanner.
While the invention has been described, disclosed, illustrated and shown in various terms of certain embodiments or modifications which it has presumed in practice, the scope of the invention is not intended to be, nor should it be deemed to be, limited thereby and such other modifications or embodiments as may be suggested by the teachings herein are particularly reserved especially as they fall within the breadth and scope of the claims here appended. | Systems, apparatus and methods for collecting, storing, processing, reconstructing, and interpreting raw scan data from a medical diagnostic imaging scan. Raw data after a scan such as a Computed Tomography (CT) scan is sent to a raw scan database system and image reconstruction system, where image volumes are reconstructed using software from the software bank and sent to a data management system. Raw scan data generated once by a scanner is continuously used at later times to reconstruct images of the patient without having to perform additional patient scans. | 6 |
BACKGROUND OF THE INVENTION
The invention relates to recycling dry fines that are generally difficult to hydrate into a main product stream. More particularly, the invention relates to reprocessing fines generated in the production of fluid absorbent polymers and copolymers.
Water-swellable polymers and copolymers are well known for their use as absorbents for aqueous fluids in diapers, sanitary products and the like. Certain of these polymers, for example those prepared from monomers of acrylic acid or methacrylie acid or their respective alkali metal or ammonium salts and typically lightly crosslinked with a crosslinking monomer having at least two polymerizable double bonds, exhibit exceptionally high capacity for adsorbing liquids and are further characterized as having good physical integrity in processing and use.
These water swellable polymers/copolymers are often employed in a particulate form of a desired particle size that effectively promotes contact with the fluid to be absorbed. In the production of acrylic acid-based copolymers by the gel formation method, a significant portion of "fines" material, that particulate material less than about 75 mesh (200 micrometers), is typically generated from the process of manufacturing the absorbent product. These processes generally include, after the gel polymer or copolymer gel is formed, a number of drying, gel breakup and grinding unit operations until an optional amount of product of a final acceptable particle size range is achieved. In the course of the process, 8-11 percent by weight of the final product may be fines, that is, particulate polymer that is finer than the desired minimum size suitable for the intended end-use of the polymer.
Initially, users employed the entire dry product, including fines, in their absorbent products. It was soon discovered, however, that the inclusion of fines resulted in lower product performance. One difficulty that often occurs when fine particles are initially contacted with an aqueous fluid is a "gel blocking" phenomenon. Upon initial hydration of a tightly packed mass of fines, only the outside layer is wetted because the fines form such a dense polymeric network that neither capillary action nor diffusion will permit penetration of the fluid into uniform contact with the interior particles. The result is a substantially reduced overall capacity of the absorbent polymer to absorb and hold aqueous fluids. In addition, for some products such as diapers, the fines material may sift from the product.
An initial solution to the fines problem was simply to screen the fines from the product. The resulting fines were stored as off-specification product with the intention of recycling the fines into the process or reprocessing them into larger sized particles through agglomeration. However, attempts at recycling the fines into the process have heretofor proved generally unsuccessful, requiring significant additional processing steps and equipment. A major difficulty with the fines particles is that they are extremely difficult to rewet for uniform blending into the main product stream.
In U.S. Pat. No. 4,950,692 superabsorbent polyacrylate fines are rehydrated to gel form by agitating for relatively long periods of time, typically one-half to one hour, followed by blending with the main gel product stream or drying and then blending with the dry product. In U.S. patent application Ser. No. 07/407,840, fines are rehydrated by rewetting under high shear conditions. While residence times for rewetting the fines are greatly reduced over U.S. '692, the recycling process does require the introduction of relatively high performance equipment into the process.
A number of workers have attempted to agglomerate fines to produce a larger size particulate for reintroduction into the product stream. These agglomeration techniques generally involved treating the fines with water or other binding agent in an environment such as a fluidized bed. The difficulty with this approach is that these processes fail to produce a product that is sufficiently bound together to survive forming into finished products without attriting and recreating the objectionable fine material, either in the process for making the aqueous fluid absorbents or in the customer's plant or product.
Thus, in view of the difficulties of the prior efforts to recycle aqueous fluid absorbent polymer fines, it would be desirable to provide a process that recycles fines into a main product stream of polymer/copolymer such that the finished product absorbent capacity and particulate integrity are equivalent to the material normally produced of a desired particle size. Such a process should not add significant processing steps or processing time.
SUMMARY OF THE INVENTION
The process of the invention is directed to recycling dry aqueous fluid absorbent polymer fines, generally polymer less than a desired size, into a process including a polymerization step for making said super absorbent polymer. The recycled fines are generally less than about 75 mesh (200 micrometers). The process comprises: P1 recovering dry polymer fines from said aqueous fluid absorbent polymer;
mixing said fines with a polymerizable monomer solution for making said aqueous fluid absorbent polymer; and
polymerizing said mixture of fines and monomer to form said aqueous fluid absorbent polymer.
Generally, the process preferably further comprises:
comminuting the aqueous fluid absorbent polymer from said polymerizing step;
drying said comminuted polymer;
separating said dried polymer particulate into a portion having a desired minimum particle size and a fines portion having less than said desired size; and recycling said fines portion to the polymerizing step for forming said aqueous fluid absorbent polymer.
The preferred aqueous fluid absorbent polymer of interest, that is, the monomer solution from which it is made, includes water-soluble ethylenically unsaturated monomer mixtures or salts thereof, preferably an amide, carboxylic acid or its esters, vinyl amines or their salts or mixtures thereof.
Most preferably said polymer is a crosslinked polymer of polyacrylic acid, sodium polyacrylate or copolymers thereof crosslinked with a polyvinyl monomer.
Said monomer solution may include a monomer capable of graft polymerizing with at least one other component of said monomer mixture.
The aqueous fluid absorbent material of the invention is preferably a water-swellable fluid absorbent gel, that is, a partially neutralized copolymer that is lightly crosslinked, preferably of acrylic acid, methacrylic acid, crotonic acid or isocrotonic acid.
The amount of fines mixed into said monomer solution is limited to that amount which does not adversely affect the desired aqueous fluid absorbent characteristics of said polymer. An advantage of the process of the invention is that a relatively large amount of fines may be recycled or reprocessed without significantly adversely affecting the aqueous fluid absorbent characteristics desired in the polymer product. The amount that may be recycled generally is substantially in excess of the 8-11 weight percent typically generated in the gel process and may range, if required, up to 30 weight percent, based upon the solids content of the polymer gel of the invention. Preferably the fines recycled portion comprises 5-15 percent based upon the solids content of the gel.
DETAILED DESCRIPTION OF THE INVENTION
In the production and handling of solid aqueous fluid absorbent polymers to produce a particulate product having a desirable particle size, for example suitable for incorporation in personal care articles such as diapers, drying and grinding portions of the typical gel process naturally create a fines fraction of particles that are undesirably small for the intended uses. This particle size fraction, hereinafter referred to as "fines", in addition to being undesirably small for the intended use is often small enough to create dusting problems in production. Such dusty fines may create materials handling problems in the process as well as represent a risk of becoming airborne in a manufacturing facility. In the products in which employed, the fines material is often a source of performance difficulties because of its well-known tendency to gel block upon initial wetting. In addition, there may also be difficulty in containing the fines in the product.
The present invention is a process by which a fines portion of an aqueous fluid absorbent polymer, created by natural attrition during its manufacture or incorporation into a useful article, is recycled into the polymerization reaction which originally created the aqueous fluid polymer. By means of this process, what has often been in the past an accepted yield loss in manufacturing and handling such materials is now minimized or eliminated. The result is a product aqueous fluid absorbent particulate that remains unitary in nature even under the stresses imposed by hydration, as can easily be seen by observation of the hydration process under low power microscope.
The water-swellable or lightly crosslinked hydrophilic polymers or copolymers that are of particular interest in the fines recycling process of the present invention are any of those capable of adsorbing large quantities of aqueous fluids. Examples of such polymers and methods for making them are found in U.S. Pat. Nos. 3,997,484; 3,926,891; 3,935,099; 4,090,013; and 4,190,562, the relevant parts of which are herein incorporated by reference. In general, such polymers are prepared from water-soluble α, β-ethylenically unsaturated monomers such as mono and polycarboxylic acids, acrylamide or their derivatives. Examples of suitable mono-carboxylic acids include acrylic acid, methacrylic acid, crotonic acid and isocrotonic acid and their alkali metal and ammonium salts, as well as sulfoethyl methacrylate and its sodium salt or 2-acrylamido-2-methylpropane sulfonic acid or its sodium salt. Suitable polycarboxylic acids include maleic acid, fumaric acid and itaconic acid. Suitable acrylamide derivatives include methylacrylamide and N,N-dimethylacrylamide. The preferred monomers include acrylic acid and methacrylic acid and their respective alkali metal or ammonium salts. The polymers may be modified, for example by inclusion of graftable moieties in the monomer solutions.
Organic compounds having two or more ethylenic groups copolymerizable with the water-soluble monomers can be used as crosslinking monomers. Exemplary multifunctional crosslinking monomers include diacrylate or dimethacrylate esters of ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, 1,4-butane diol and the like, as noted in U.S. Pat. No. 4,286,082. Others are methylene bisacrylamide, di- and tri-allylamines and allyl [meth]acrylate esters. The degree of crosslinking is selected such that water absorption capacity of the polymer is not reduced or so low that the absorbent becomes sticky on contact with fluid and exhibits a low initial absorption rate.
The preferred aqueous fluid absorbent particulate is derived from a monomer solution comprising polyacrylic acid. In the most preferred solution, the polyacrylic acid is at least partially neutralized and partially crosslinked salt. The monomer mixture solution may include graft polymerizable moleties such as starch, polyvinyl alcohol and the like, as well as other monomers that copolymerize with polyacrylic acid or its salt. In the process, the acrylic acid is preferably neutralized with an alkali base such as a sodium, ammonium, potassium hydroxide or carbonates.
In the partially neutralized, partially crosslinked polyacrylic acid monomer system, the acrylic acid concentration in the polymerization phase will range from about 10 to 40 weight percent based upon the solids concentration of the gel in the reactor. Preferably, the acrylic acid concentration in the monomer solution is about 20 to 40 percent and most preferably 25 to 35 percent. The acrylic acid component will generally be about 30 to 100 percent neutralized, preferably 40 to 80 percent, most preferably 55 to 75 percent. In general, a crosslinker, if utilized, will range from 0,001 to 5 percent, based upon the weight of solids in the reactor with a preferred range of 0.2 to 1 percent. The polymer fines that may be recycled to the process may comprise up to at least about 30 percent by weight based upon the solids in the reactor. A preferred operating range is 5 to 15 percent by weight, in order to minimize impact upon aqueous fluid absorbent performance qualities of the product.
The method and apparatus for making the gel polymerization product is entirely conventional, except for recycling the fines to the monomer solution prior to the polymerization step. The equipment utilized is also conventional with the principal reaction vessel typically a simple vertically agitated vessel or a horizontal single screw cylindrical mixer as described in U.S. Pat. No. 4,769,427 and EP 0 238 050. Other reactor vessels known in the art are suitable and other reaction devices such as a twin screw extruder described in U.S. Pat. No. 4,625,001 or a belt polymerizer described in U.S. Pat. No. 4,851,610 may be utilized.
In the polymerization step all well-known free radical initiation systems maybe utilized, including initiation systems based entirely on thermal initiators, as well as the many different combinations of redox initiation systems. The amounts of initiator employed are those chosen based on the needs the particular polymerization equipment and conditions of temperature and pressure at which it is desired to operate that equipment and are not otherwise constrained.
Generally, the water-soluble monomer and crosslinking monomer are polymerized in the presence of a polymerization initiator in any known manner such that a gel-like reaction product results. The gel polymer is dried, preferably by hot air at about 50° to 200° C. such that the moisture content of the polymer gel is between about 0.01 and 15 percent based on the total weight of the dried absorbent polymer. The dried polymer is then comminuted into a particulate product having a desired size particulates.
The following examples illustrate the products and process of the invention and are not intended to limit the invention only to their scope.
EXAMPLES 1, 2 and COMPARATIVE EXAMPLE A
Acrylic acid is charged to a one-liter reaction kettle provided with agitation followed by addition of trimethylolpropane triacrylate (TMPTA) crosslinking agent which after several minutes of stirring dissolves in the acrylic acid. To this solution is added Versenex® 80 chelating agent (40 percent aqueous solution of pentasodium salt of diethylene triamine pentacedic acid available from The Dow Chemical Company) and Airvol® 205, a low viscosity polyvinyl alcohol that is 87-89 percent hydrolyzed and has a 4 percent solution viscosity of 5-6 cp at 20° C. and is manufactured by Air Products Co. of Allentown, Pa., for stabilizing the TMPTA in aqueous medium. The monomer solution is then partially neutralized to about 65 percent of neutrality, with a sodium carbonate solution. The rate of addition of the alkali material is adjusted to accommodate CO 2 evolution.
In accord with the invention, polymer fines are added to the neutralized monomer mix with agitation. Again, the rate of agitation is controlled to avoid excess foaming of the CO 2 supersaturated monomer mixture. No fines are added for Comparative Example A.
The reactor contents are deoxygenated for 60 minutes and the initiator components are introduced. Polymerization is initiated and the temperature is allowed to rise to an initial desired level. The reactor is then maintained at a desired hold temperature for a period of time necessary for high monomer conversion to be achieved. In cases where higher levels of fines are added to the polymerization, the total heat release was reduced compared to the Comparative Example A polymerization. To insure similar temperature profiles for all polymerizations, a heated bath was employed to eliminate any differences derivable from differences in heat history.
The reaction is allowed to proceed until complete as evidenced by conversion of the monomers to polymer. After conversion is complete, the gel is removed from the reactor in small pieces that are then spread onto a nylon screen and dried in an oven at about 100° C. for about 16 hours. After drying, the polymer is cooled to room temperature and is pulverized to the desired particle size.
After the polymer is dried and ground to final particulate size, it is analyzed for residual acrylic acid, extractable centrifuge capacity, shear modulus, and absorption under load.
The above-process was repeated varying the amount of polymer fines introduced into the monomer solution between about zero and about 16.7 weight percent fines, based on the solids remaining in the finished, dried polymer. The ingredients employed in the process are shown in Table I below.
TABLE I______________________________________ Example 1 Example 2Polymerization (8.3% (16.7% ComparativeIngredients (g) Fines) Fines) Example A______________________________________Acrylic Acid 273 250 300TMPTA 1.91 1.75 2.1Versenex V-80 1.82 1.67 2.0Airvol 205, 5% 1.36 1.25 1.5Na.sub.2 CO.sub.3 131 120 144Water 801 801 801Fines 30 60 NoneINITIATORSH.sub.2 O.sub.2 (30%) 1.0 1.0 1.0Na.sub.2 S.sub.2 O.sub.8 (10%) 5.0 5.0 5.0Na erythorbate 0.6 0.6 0.6(10%)______________________________________
The fines employed in the examples are screened from conventional production DRYTECH® polymer which is a partially neutralized, partially crosslinked aqueous fluid absorbent polymer based on acrylic acid manufactured by The Dow Chemical Company in accord with Comparative Example A as described in U.S. Pat. No. 4,833,222, the relevant portions of which are incorporated by reference. The DRYTECH® polymer fines material employed is less than about 140 mesh (110 micrometers) and is derived from production material having an average 30 minute centrifuge capacity of 30.5 g/g, a 4-hour aqueous extractables of 7.2 percent and a residual acrylic acid monomer of 470 ppm.
Characteristics of the qualities of the dry particulate aqueous fluid absorbent polymer, for each level of fines addition to the polymerization step, are reported in Table II for polymerization hold temperatures of 80° and 50° C.
TABLE II__________________________________________________________________________ Centrifuged Capacities Residual 30 min. AUL % acrylic acid Modulus [g/g] [g/g] Extractables [ppm] [dynes/cm.sup.2 ]Example 50° C. 80° C. 50° C. 80° C. 50° C. 80° C. 50° C. 80° C. 50° C. 80° C.__________________________________________________________________________Example 1 25.7 28.2 -- 24.7 2.5 7.3 1710 807 40,400 35,800Example 2 24.5 27.9 -- 24.1 2.4 9.3 4087 718 40,300 31,700Comparative 28.4 29.9 -- 25.1 2.4 7.4 3533 816 35,900 30,100Example A__________________________________________________________________________ .sup.1 The procedure for determining Centrifuged Capacity is described in EP 0 349 241, the relevant portions of which are incorporated by reference. .sup.2 The procedure for determining Absorbency Under Load (AUL) is described in EP 0 339 461, the relevant portions of which are incorporate by reference. .sup.3 The procedures for determining Percent Extractables and Residual Acrylic Acid are determined by dispensing 2 g of 80/100 mesh screen cut o polymer in 370 ml of 0.9 percent saline solution, shaking for 4 hours and filtering. The filtrate is then subjected to liquid chromatography to determine Residual Acrylic Acid and filtrated for acid content to determine percent extractables. .sup.4 The procedure for determining Modulus is described in RE 32,649, relevant portions of which are incorporated by reference.
Table II shows the effect of added fines on 30 minute centrifuge capacity of the polymerization product. The centrifuge capacity decreases with added fines.
EXAMPLE 3
A series of polymerizations identical to those of Examples 1 and 2 are performed for fines levels of 8.3 and 16.7 percent except that the amount of TMPTA crosslinker agent was varied. Table III reports the affect of crosslinker variation on centrifuge capacity for the two fines contents.
The absorbency under load (AUL) test measures the way in which polymer swells under pressure. Where recycled rehydrated fines have been added to the gel, by the method of the prior art, a decrease in AUL with increased fines addition level was experienced. Adding fines to the monomer prior to polymerization in accord with the present invention achieves satisfactory AUL without a substantial reduction in AUL. While there is some reduction at higher crosslinker levels, the degree of reduction is acceptable in view of the overall characteristics of the dry product achieved.
TABLE III__________________________________________________________________________ Centrifuged % Capacities Extractables AUL ModulusAmount Hold 30 min. [g/g] [%] [g/g] [dynes/cm.sup.2 ]of TMPTA Temperature 8.3% 16.7% 8.3% 16.7% 8.3% 16.7% 8.3% 16.7%(%) (°C.) fines Fines fines Fines fines Fines fines Fines__________________________________________________________________________0.7 80 28.2 27.9 7.3 9.2 24.7 24.1 34,100 31,7000.5 80 29.9 28.6 10.6 11.8 22.6 23.8 24,000 28,4000.3 80 32.8 30.4 13.1 12.9 21.3 20.4 21,200 24,3000.7 50 -- 28.6 -- 3.2 -- 27.8 -- 36,6000.5 50 -- 27.6 -- 5.8 -- 24.8 -- 35,6000.3 50 -- 27.5 -- 6.1 -- 26.1 -- 35,700__________________________________________________________________________
Table III of Example 3 shows the response of centrifuge capacities to changes in TMPTA level for two levels of fine addition. A significant reduction from 0.7 percent TMPTA to to 0.3 percent TMPTA at 16.6 percent fines at an 80° C. whole temperature was required to bring the 30 minute centrifuge capacity back up to the zero fines level. A larger reduction in TMPTA level would have been required at lower whole temperatures.
EXAMPLES 4-6
Sodium acrylate aqueous fluids absorbent polymer is made utilizing a 200 liter reactor, employing a scaled-up version of the lab recipe noted above, at a higher solids content. Fines added to the monomer are at about a 7, 15 and 20 percent, based upon the solids content of the gel product. Table IV reports the results of these examples, which are consistent with those presented above wherein the centrifuged capacity decreases with increasing recycled fines levels with all other properties remaining in the normal and acceptable range.
TABLE IV______________________________________ Example Example ExampleExamples 4 5 6______________________________________Fines, % 7 15 20Cent cap, (30 min) 29.4 26.8 25.1g/gAUL, g/g 26 23 2416 hr ext, % 5.6 4.7 4.5Residual AA, ppm 416 800 251______________________________________
EXAMPLE 7 AND COMPARATIVE EXAMPLES B AND C
Test Procedure
A beaker containing 40 ml of saline solution is vigorously stirred on a magnetic mixer. Two grams of an aqueous fluid absorbent polymer are added and the time is recorded for the disappearance of the vortex caused by the magnetic stirrer. A second 10 ml portion of saline solution, this portion containing a blue dye, is added and absorbency observed.
Examples Tested
An aqueous fluid absorbent product comprising (1) agglomerated fines and designated as Comparative Example B; (2) a product produced by blending a hydrated fines particulate with gel and designated as Comparative Example C; and (3) the product of the present invention requiring recycling fines to the polymerization process and designated as Example 7 are tested as indicated above.
Comparative Example B is made by mixing fines with water at high speed, drying and screening to produce a 20 to 100 mesh particulate. Comparative Example C is made by the process of hydrating fines at high shear in accord with U.S. patent application Ser. No. 07/407,840.
Results
For materials made by Comparative Examples B and C of the prior art, the blue dye penetrated only about 1/4 of volume of the original swollen gel. In the test for Example 7, the product of the process of this invention, the blue color was present throughout the volume of the beaker.
The non-uniformity of the blue color for the first test indicates gel blocking as the particles come apart during hydration. The breaking-up of product into small pieces upon hydration is observable under a low power microscope. The uniform blue color appearing with the product of the invention indicates that no gel blocking has occurred and that the product retains its unitary nature even under the stresses imposed by hydration. | A process is described for recycling dry aqueous fluid absorbent polymer fines into a process that includes a polymerization step for making the aqueous fluid absorbent polymer. The process requires recovering the dry polymer fines, mixing the fines with a polymerizable monomer solution for making the aqueous fluid absorbent polymer and polymerizing the mixture of fines and monomer to form the aqueous fluid absorbent polymer. In the process the fines are incorporated into the new polymer gel and becomes indistinguishable therefrom. The gel may then comminuted into a particulate dried and then separated into a portion having a desired minimum particle size in a fines portion having less than the desired size. The fines portion is then recycled up to about 30 percent by weight based on gel solids may be recycled for the preferred polyacrylate based aqueous fluid absorbent polymer. | 0 |
CROSS REFERENCE TO RELATED PATENT APPLICATION
The present patent application claims the priority of U.S. 61/690,515 filed Jun. 28, 2012, which application is incorporated herein by reference.
FIELD OF INVENTION
The present invention relates to an exerciser, particularly to a lower body exerciser.
DESCRIPTION OF RELATED ART
As the pace of life getting faster and faster, more and more people are in sub-health state. Especially for those people who are long-term engaged in desk work. Because of long working hours, their lower bodies are lack of physical exercises and accompanied by feeling of fatigue difficult to be recovered. People need exercisers to train and build their bodies for health. Practically, many people are too busy to go to the gyms and they even hope to be working while performing exercises.
However, because of the complicated configuration, the conventional exercisers are heavy and bulky. It also increases the cost for storage and transportation. This kind of exerciser is not suitable to be used in a limit indoor space such as bedroom, living room or an office at any time. For some lower body exercisers with relative simple structures and appropriate sizes, the training positions and angles for exercise are lack of variations. Therefore, the conventional exercisers mainly perform stretching exercises to build lateral and internal leg muscles, the lower body could not get sufficient workout.
SUMMARY OF THE PRESENT INVENTION
It is therefore one object of the present invention to provide a lower body exerciser for solving the problems existing in the conventional exercisers and further to provide more different exercising methods in order to provide more options for exercise to get better workout.
The lower body exerciser mainly comprises: a central base; two support brackets located at each side of the central base respectively; two slide tracks connecting between the central base and each of the two support brackets respectively; two foot pedals mounted on each of the two slide tracks respectively; a connecting base matched with the slide track, fixed under each foot pedal and used for rotating around the slide track and sliding along the longitudinal direction of the arc-shaped slide track. A plurality of O-Ring elastic bands are mounted around the pulley sets disposed on the central base, the foot pedals and the support brackets to generate tension for exercise. The two slide tracks are hinged at each side of the central base respectively, so the exerciser is foldable and can stand in an upright position for fast and easy storage. Compared to the long training commitment products, this lower body exerciser helps strengthening and defining thighs, calves and hips muscles with minimizing time and maximizing positive results.
Effects of the Present Invention
1. Because the foot pedals could slidably and rotatably fit with the arc-shaped slide track, not only the lateral and internal leg muscles, but also the front and back muscles of buns, hips, thighs, calves are effectively trained while the user is moving the foot pedals.
2. The O-Ring elastic bands are utilized together with the pulley sets to generate tension for exercise. The user can increase or decrease tension by changing the O-Ring elastic bands from light, medium or harder tension to get different exercise workout.
3. The lower body exerciser has simple configuration, light weight to allow the user to utilize at a small space, and it could be folded and then stand in an upright position and is small enough for fast and easy storage.
Further benefits and advantages of the present invention will become apparent after a careful reading of the detailed description with appropriate reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a top view of the lower body exerciser in accordance with the present invention;
FIG. 2 shows a bottom view of the lower body exerciser in accordance with the present invention;
FIG. 3 shows a partial bottom view of the lower body exerciser in accordance with the present invention;
FIG. 4 shows a view of the lower body exerciser being in use in accordance with the present invention;
FIG. 5A shows a cross section view of an embodiment in accordance with the present invention;
FIG. 5B shows a perspective view of the embodiment shown by the FIG. 5A ;
FIG. 6A shows a cross section view of another embodiment in accordance with the present invention;
FIG. 6B shows a front view of the embodiment shown by the FIG. 6A ;
FIG. 6C shows a perspective view of the embodiment shown by the FIG. 6A ;
FIG. 7A shows a cross section view of another embodiment in accordance with the present invention;
FIG. 7B shows a perspective view of the embodiment shown by the FIG. 7A ;
FIG. 8A shows a right perspective view of the lower body exerciser being folded in accordance with the present invention;
FIG. 8B shows a front view of the lower body exerciser being folded in accordance with the present invention;
FIG. 8C shows a left perspective view of the lower body exerciser being folded in accordance with the present invention;
FIG. 9 shows a perspective view of the central base with a handle grip in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, similar symbols typically identify similar components, unless context dictates otherwise. The illustrative embodiments described in the detailed description, drawings, and claims are not meant to be limiting. Other embodiments may be utilized, and other changes may be made, without departing from the spirit or scope of the subject matter presented here. It will be readily understood that the aspects of the present disclosure, as generally described herein, and illustrated in the Figures, can be arranged, substituted, combined, and designed in a wide variety of different configurations, all of which are explicitly contemplated herein.
The lower body exerciser is created with unique ergonomic design to naturally follow the inward or outward legs movements with the machine and more functions to tone and shape the lower body parts in order to achieve the best legs, hips and thighs workout. According to certain embodiment of the present disclosure, following figures could show the schematic structural views of the body exerciser provided by the invention.
Referring to FIG. 1 to FIG. 4 , the body exerciser comprises a central base 1 , two support brackets 2 , two slide tracks 3 , two foot pedals 4 . The central base 1 with a handle grip includes a left side and a right side. The two support brackets 2 locate at each side of the central base 1 respectively.
The two slide tracks 3 are connected with the central base 1 and each of the two support brackets 2 respectively. To allow the foot pedal 4 to slide smoothly, the slide track 3 could be circular tube or tubular rail made of metal material such as stainless steel or Aluminum or Titanium. The two foot pedals 4 are mounted on each of the two slide tracks 3 respectively. The foot pedal 4 is designed with ergonomic convex surfaces to match the foot contour. The connection between the foot pedal 4 and the slide track 3 is via a connecting base 41 . The connecting base 41 is fixed under each foot pedal 4 and matches with the slide track 3 . The connecting base 41 is used for rotating around the slide track 3 and sliding along the longitudinal direction of the slide track 3 . The foot pedal 4 could be tilted upward or downward on the slide track 3 .
A plurality of pulley sets are disposed on the body exerciser. A plurality of elastic bands are mounted around the pulley sets. The pulley sets and the elastic bands form a tension generation system. In some embodiments, a first pulley set 11 consists of four pulleys, wherein two pulleys are disposed on the left side of the central base 1 , and the other two pulleys are disposed on the right side of it. Two second pulley sets 21 are respectively disposed on each of the two support brackets 2 . The second pulley set 21 consists of two pulleys disposed at each end of the support bracket 2 respectively. A third pulley set 42 is disposed under the connecting base 41 or each of the foot pedals 4 . The third pulley set 42 consists of one (as shown in the FIG. 3 ) or two pulleys (as shown in the FIG. 1 and FIG. 2 ). Each of two first elastic bands 51 is mounted around the first pulley set 11 and the third pulley set 42 at each side of the central base 1 . Each of the two second elastic bands 52 is mounted around the second pulley set 21 and the third pulley set 42 at each side of the central base 1 respectively. Both the first elastic bands 51 and the second elastic bands 52 are O-Ring elastic bands.
When in use, no matter indoor or outdoor, a user just needs to sit in a chair and step both feet on the two foot pedals 4 . The user moves the foot pedals 4 with feet to slide along the longitudinal direction of the slide tracks 3 (as shown in FIG. 4 ). As feet moving toward the support brackets 2 (outward movement), the first elastic bands 51 will generate resistance to prevent the foot pedals 4 from moving. The foot pedals 4 are pulled by the first elastic bands 51 , the second elastic bands 52 are released. Otherwise, as feet moving toward the central base 1 (inward movement), the foot pedals 4 are pulled by the second elastic bands 52 , and the first elastic bands 51 are released. The third pulley set 42 is a pulley guide, which is designed to pull the O-Ring elastic bands in the inward or outward directions to create tension to the exercises. To move the foot pedals 4 , the user has to exert force to overcome the resistance of O-Ring elastic bands. All pulleys of the first pulley sets, the second pulley sets and the third pulley sets are rotational, so that when the O-Ring elastic bands are pulled by the foot pedals pulley guide, all the pulleys will automatically turn to assist the stretching of the elastic bands for providing more smooth movements during the exercise. By repeating the inward and outward movements, buns, hips, thighs, calves are stretched and muscles are exercised, even the user is operating a computer, watching TV, writing a paper or doing anything else sitting in the chair.
The O-Ring elastic bands have three different resistance degrees. The user can increase or decrease tension by changing the O-Ring elastic bands from light, medium or harder tension just in seconds. The user can also connect one or two O-Ring elastic bands at the same time to provide tension in different directions.
The slide track 3 could be various shapes such as being straight (not shown in the figures) or arc. As conventional exercisers, the user horizontally moves the foot pedals 4 along the straight slide tracks 3 , only the lateral and internal leg muscles are stretched. In some embodiments, the two slide tracks 3 are arc-shaped. The diameter of the arc is 160 cm. Therefore, when the user moves foot pedals 4 along the arc-shaped slide tracks 3 , the buns, hips, thighs and calves muscles are worked to shape and tone at the same time. The arc-shaped slide tracks 3 also could be downwardly curved.
A counter device is disposed on the lower body exerciser to help the user counting times of repetitive actions. The counter device comprises a pair of sensors and an indicator. The sensors are mounted on the connections between the central base 1 and the slide tracks 3 . One sensor is mounted on the left side of the central base 1 , and the other one is mounted on the right side of the central base 1 . The sensors are connected with the indicator fixed mounted on the top of the central base 1 . Once the foot pedal touches the sensor, the indicator will show the times of accumulative actions.
The connecting base 41 comprises a through hole 411 configured to allow the slide track 3 to pass through. In order to work the hips, calves and buns, the user might choose the tilting positions to work the muscles in different angles. A plurality of sliding members are mounted in the through hole 411 . The slide members are slidably and rotatably fitted with the slide track 3 , so that the foot pedal 4 is allowed to travel along the longitudinal direction of the tubular slide tracks 3 and to tilt in multiple slopes and angle positions from down or up simultaneously (as shown in FIG. 1 ).
Referring to FIG. 5A and FIG. 5B , in some embodiments, the sliding members are balls 412 with hollow holes fitted over each slide track 3 . The balls 412 movably fit with the connecting base 41 . The interior of the hallow holes of the balls 412 are in full contact with the surface of the slide track 3 and made to slide and move freely against the slide track 3 . Two balls 412 are disposed inside the connecting base 41 . The connecting base 41 relatively rotates around the balls 412 , so that the foot pedal 4 could tilt with arbitrary angles. The balls 412 could be ball knobs made of nylon or high quality plastic for best sliding performance
Referring to FIG. 6A˜FIG . 6 C, in some embodiments, the sliding members are trolley wheels 413 . Since the slide track 3 is tubular, the trolley wheels 413 are rotatably mounted on each slide track 3 . Four trolley wheels 413 equipped with recesses 4131 fitted with each slide track 3 . Two of the wheels 413 are mounted on one side of the slide track 3 , and the other two are mounted on the other side of the slide track 3 . The balls 412 and the trolley wheels 413 follow the shape of the slide track 3 in a very smooth sliding movement without any noise.
Referring to FIG. 7A and FIG. 7B , in some embodiments, the sliding members are shaft housings 414 fixed connecting to the connecting base 41 at both sides of the through hole 411 . The interior of each shaft housing 414 is made to be convex to suitable for the slide track 3 , especially for the arc-shaped one. The connecting base 41 and the foot pedal 4 may be integrally molded as a whole. The shaft housings 414 are fixed with the connecting base 41 and the foot pedal 4 .
Referring to FIG. 8A˜FIG . 8 C, in some embodiments, the two slide tracks 3 hinge at each side of the central base 1 respectively. One side of the slide track 3 is connected to the central base 1 , and the other side is connected to the support bracket 2 , so that the lower body exerciser could be folded. Referring to FIG. 9 , an ergonomic handle grip 12 is disposed on the central base 1 . The handle grip 12 has been designed with oval-shaped sectional contour for comfortable holding. After the exercise finished, the user could hold the handle grip 12 to lift up the lower body exerciser into an upright standing folded form to carry or store.
The lower body exerciser has light weight to allow the user to use at any indoor or outdoor situations such as at home, office, health clubs, fitness room, rehab center or physical therapy room. The exerciser is generally for people who want to get stronger and better looking thighs and legs in less time and can be used anywhere by any age. It only requests a small space to operate with a chair and is small and light enough for fast and easy storage.
Thus, the lower body exerciser has been described. Although the present disclosure has been described with reference to specific exemplary embodiments, it will be recognized that the disclosure is not limited to the embodiments described, but can be practiced with modification and alteration within the spirit and scope of the appended claims. Accordingly, the specification and drawings are to be regarded in an illustrative sense rather than a restrictive sense. | A lower body exerciser mainly comprises: a central base; two support brackets located at each side of the central base respectively; two slide tracks connecting the central base with each of the two support brackets respectively; two foot pedals mounted on each of the two slide tracks respectively; a connecting base being fixed under each foot pedal, matched with the slide track, and used for rotating around and sliding along the longitudinal direction of the arc-shaped slide track. A plurality of O-Ring elastic bands are mounted around the pulley sets to generate tension for exercise. The two slide tracks are hinged at each side of the central base respectively, so the exerciser is foldable for convenient carry and storage. This lower body exerciser could help to strengthen and define thighs, legs, buns and hips muscles with minimizing time and maximizing positive results. | 0 |
BACKGROUND OF THE INVENTION
A filter unit has an important function to fulfil in today's society since polluted air is generated in many places. Such air can be supplied to the inlet opening of a filter unit, pass through it, and shed all impurities so that clean air flows out of the outlet of the filter unit and can be mixed with air in the normal atmosphere. The filter in a filter unit can be constructed in many different ways. It may be constructed mechanically and consist of various layers of material that permit diffusing. The problem with existing filter units is that they require frequent servicing and service is expensive. It is therefore desirable to provide a filter for which the service intervals are as long as possible.
The object of the present invention is to provide a filter unit that forms part of an industrial plant and where maximal intervals are obtained between servicing. The filter unit has an inlet opening and an outlet opening. The outlet opening is connected to an extractor that produces negative pressure. The inlet opening of the filter unit is connected, via a connection unit, with a unit that generates polluted air. In accordance with the invention a number of part-filter units are stacked one above the other so that a series-connected filter is obtained. Each part-filter comprises a number of filter mats located parallel with the flow direction of the air and also with each other. The individual mats are spaced from each other and are suitably formed from a single fibre mat that is pleated. A mat consists of an intermediate layer and a surface layer on each side of the intermediate layer. The surface layer consists of fibres that are thermally joined and form permeable openings for air containing particles. Between said surface layers is an intermediate layer suitably having a thickness of between 10 and 20 mm The intermediate layer consists of several layers of fibres and its diameter may be between 5 and 15 μm. The intermediate layer may have a density of 100-200 kg/m 3 . Polluted air can pass through such a part-filter unit with fibre mats in the direction of the stacked part-filter units. When flowing air enters a part-filter unit it is arranged to flow through a mat. The filtering property obtained through flowing air is dependent on the speed at which it passes through the mat and the density of the mat. It has been found that if the flow velocity through the mat is lower than preferably 0.1 m/s the particles to be sorted out will fall down against the flow direction so that the part-filter unit becomes substantially self-cleaning. The filtering action is thus dependent on the flow velocity through the mat, the density of the mat and the size of the fibres. The fibres in the mat may be pinned.
In certain cases it may be advisable to have an intermediate layer consisting of two layers, in which case one layer may be of the same type as that described above. The additional layer has fibres that are randomly oriented and suitably have a diameter of 0.5-3.5 μm. The layer may have a thickness of about 5-10 mm and a density suitably lying between 20 and 30 kg/m 3 .
Each of the various part-filter units in a stack is intended for particles of a predetermined size. The number of part-filter units desired is determined by how polluted the air is. The part-filters stacked one on top of the other can together supplied air that is absolutely free from particles.
The part-filter located nearest the exit of the filter unit is a security unit for the entire filter unit. In this filter unit the fibre mats consist of a HEPA mat which guarantees filtration of 99.97% and filters particles with a diameter of down to 3 μm. This part-filter unit thus guarantees that the total filter unit will function if any of the previous part-filters fails to function. If the previous part-filters function perfectly there will be extremely low load on the filter nearest the exit from the filter unit.
The velocity of polluted air from operating machines should be adjusted by the extractor to 20 m/s in order to prevent impurities becoming lodged on the transfer unit. A collecting unit is arranged at the inlet to the filter unit to collect liquid and heavy particles. A velocity of 6 m/s is suitable for the air flowing into the inlet opening of the stacked part-filter units.
The filter mats in a part-filter unit may be arranged in a tubular magazine that is open at the top and bottom and forms a unit that is easily replaceable when servicing is required.
The extractor arranged at the outlet end of the filter unit may be built into the filter unit to form a single unit or it may be arranged separate from the filter unit.
The extractor, filter unit and transfer means should constitute a hermetically sealed unit.
To obtain the correct speed a number of sensors are placed at various points in a complete plant and connected to a control unit which in turn regulates the air flow.
The air flow through a filter mat is controlled by the negative pressure prevailing on the side where the air leaves the mat after having passed through it.
Additional characteristics of the present invention are revealed in the following description describing one embodiment of the invention and in the appended claims.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
The invention will be described in more detail with reference to the accompanying drawings in which
FIG. 1 shows a plant comprising a filter unit with connections to a converting machine,
FIG. 2 shows a pleated filter mat intended for a magazine,
FIG. 3 shows an enlarged view of part of the filter mat in FIG. 2 ,
FIG. 4 shows a cross section through the partial view shown in FIG. 3 ,
FIG. 5 shows a pleated filter mat for a magazine with two layers between the outer layers
FIG. 6 shows an enlarged view of part of FIG. 5 , and
FIG. 7 shows a cross section through the partial view in FIG. 6 .
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 illustrates a complete air-purifying plant for a converting machine where 1 designates a converting machine producing impurities that may consist of particles in the air. The impurities produced are designated 2 and they are drawn up through a cowl 3 which may be of any design whatsoever depending on the source of pollution 1 . The impurities are drawn up through a pipe 4 and supplied to a chamber 5 where the air containing impurities may shed heavier particles and liquid. The air then passes through the part-filter units 6 - 8 and is supplied to a fan 9 with an outlet through which the air is released to the surroundings. The fan is of medium-pressure radial type with blades bent backwards, and is suitably located in a sound-dampening chamber. Particles falling from the outer mats above are collected in the space 5 . Liquid and particles collected in the space 5 are then carried to a container 10 . The ventilation plant is so designed that the air passing through the pipe 4 has a velocity of about 20 m/s. When the air enters the space 5 at this speed it acquires a velocity of about 2 m/s thanks to the circumference of the chamber. The air then passes into the part-filter unit 6 with a velocity of between 4 and 6 m/s. When the air leaves the part-filter unit 6 it is supplied to the part-filter unit 7 . Air transported further has a velocity of between 4 and 6 m/s. When the air is supplied to the filter part 8 it also has a velocity of between 4 and 6 m/s. The suction at the upper end of the filter unit can be achieved by any type of suction means placed arbitrarily. The cowl 3 , pipe 4 and filter unit with the three part-filter units are so arranged that maximum suction effect is obtained from the fan 9 . In FIGS. 2 , 3 and 4 the filter mat is illustrated in the part-filter unit 6 as being placed in a magazine. The filter mat has two surface layers 11 and 12 which consist of a thin layer of fibres having a diameter of between 20 and 40 μm. The thickness of the layer is between 0.2 and 04. mm. The fibres of the layer are joined together by a thermal process and the layer allows through particles of up to a predetermined size. A layer 13 is arranged between the two surface layers and consists of several layers of fibres having diameters between 5 and 15 μm. The thickness of the layer may vary depending on the size of the particles in the polluted air and on how many particles the air contains in mg/m 3 . The thickness selected may be a compromise between how large a part of the particles are filtered away and how long the service life of the filter is. The thickness of a layer may be between 10 and 20 mm and the layer may have a density of 100 to 200 kg/m 3 . To enable good filtering the air is permitted to pass with a velocity of less than 0.1 m/s. The particles clump together and form drops and, thanks to the structure of the layer, its density and the low speed, they can pass downwards and leave the filter. The filter thus has a self-cleaning function.
The part-filter unit 7 has the same surface layers as in the part-filter unit 6 , and also contains the intermediate layer present in the filter mat in the part-filter unit 6 . The filter mat in the part-filter unit 7 also has an additional layer consisting of fibres having a diameter of between 0.5 and 3.5 μm. The fibres in the second intermediate layer are randomly oriented and the layer is suitably 6 mm thick and has a density of between 5-10 kg/m 3 . After the part-filter unit 7 follows the part-filter 8 where the filter mat consist of a HEPA filter, the most important function of which is to enable a guaranteed degree of filtration since it is classified. The HEPA filter has a filtration capacity of 99.97% for particles of 3 μm. The space between two filter mats in the first filter mat is designated 14 . As regards the filter mat in the part-filter unit 7 with two intermediate layers, these are designated 16 and 17 , the surface layers are designated 15 and 18 , and the space between two filter mats is designated 19 .
Since the filter mats of each part-filter unit are arranged in a magazine it is extremely easy to replace a magazine.
A control system with sensors arranged in various parts of the plant is provided to control the velocities of the ventilation plant. The system controls the movable parts that can influence the air flow.
With the aid of the plant containing the filter unit and thanks to the structure of the filter mats and the velocity of the air through the filter mats, a filter unit can be provided that achieves total cleansing of the air flowing through it in such a way that self-cleaning occurs, thereby enabling considerable time saving between each service. Naturally a larger number of part-filter units can be arranged over and above said air cleaning if necessary. | Converting machines give rise to polluted air which must be removed with the aid of fans and filters. The invention aims at removal of the polluted air in such a way that the servicing interval is greatly extended by the use of a filter unit having a number of part-filters arranged one after the other and formed of pleated fiber mats, the various mats having different filtering properties. | 8 |
This application is a continuation-in-part of application Ser. No. 601,964 filed Apr. 19, 1984, now abandoned.
SUMMARY OF THE INVENTION
The present invention relates generally to the preparation of leather products, and, particularly to the manufacturing of the vamp and quarter of a shoe. It achieves a savings of labor as well as a promotion of product quality level by means of an automated edging and flanging operation.
The preparation of leather vamps is typically accomplished by first setting the pattern in the form of a vamp by cutting, and secondly, forming a pattern or form by flanging or edging to increase the rigidity or embellishing features of the vamp. Edging and flanging are traditionally done manually by one skilled in the art, who, as a rule, presses out the edge for hammering reinforcements by holding the hammer in one hand, and the flattening tool in the other hand. Shortcomings in such a traditional method of edging processing include fatigue on the part of the operator, whose mood or morale will leave its due effects on the setting of the edging as a function of the hammering strength, right or wrong, deviated or not. In short, workmanship can hardly be put under control in mass production with such a conventional procedure of preparation to the making of a shoe.
In recognition of the foregoing, resulting from the practices prevailing in most shoe making industries, the inventor undertook to develop improvements, and finally succeeded in the introduction of the present invention.
The primary object of the present invention is to provide an automatic machine for the preparation of a shoe so as to save the labor for other activities, at a substantial cut in production costs and a substantial increase in quality in mass production.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a three-dimensional perspective of the leather product edging machine, according to the invention, with the shell casing removed;
FIG. 1B is a bottom view of the connector uniting the underside of the machine of the present invention to the body;
FIG. 1C is an example of a leather product produced according to the invention; and
FIG. 2 is a three-dimensional perspective of the skeleton on which the structure according to the invention rests.
FIG. 3 is an exploded perspective showing the construction of the present invention, with certain parts removed, in relation to a cross-section of the frame to which it is attached;
FIG. 4A a perspective of the invention similar to that in FIG. 3, except that other parts are included and other parts, including the vertical pressing stem, are removed. Arrows show direction of movement.
FIG. 4B details the construction of the transverse guide stem and associated parts. Arrows show direction of movement.
FIG. 5 illustrates the operation of the advance recoiling mechanism. Arrows indicate direction of movement.
FIG. 6 illustrates the longitudinal movement of the wrench stem by rotation of the cam shaft. Arrows show direction of movement.
FIG. 7 illustrates the axial rotation of the wrench stem and associated claw when activated by the slide bar. Arrows show direction of movement.
FIG. 8 illustrates wrenching adjustment. Arrows show direction of movement.
FIG. 9A illustrates the longitudinal motion of the vertical pressing stem and associated parts, as activated by the eccentric cam of FIG. 9A. Arrows show direction of movement.
FIG. 9B illustrates the construction and attachment of the eccentric cam.
FIG. 10 illustrates, in cross-section, the structure of the support tube and associated parts. Arrows show direction of movement.
FIG. 11 shows the edging of a leather object using the device of the present invention. Arrows indicate direction of movement.
A description of some of the reference numbers: 3 bending mound, 4 operation board (preferably gloss-finished), 5a-5f recovery springs, 6 vertical pressing stem, 7 eccentric cam, 8 mounting surface, 9 cam shaft, 10 belt wheel, 11 cylindrical cam, 12 standing stem, 13 transverse guide stem, 14 radially extending support, 15 fix block, 21 advance recoiler, 22 fix fulcrum, 23 lever, 24 pull bar, 27 arm rest, 31 curved sheave wheel, 32 curved groove, 33 swing rod, 34 extension arm of the swing rod, 35 wrench adjuster, 36 screw hole, 37 adjustment lever, 38 insertion pin, 39 swing rod groove, 40 double bending shaft, 41 vertical elbow lever, 42 horizontal elbow segment, 43 fix block, 50 slide bar set dado, 51 slide bar, 52 kettle, 55 annular piece, 56 slide bar shaft, 57 annular piece shaft, 66 flanged member, 67 blade, 71 wrench stem, 72 wrench claw, 73 wrench arm, 75 fix cap, 80 connector, 81 adjustment knob, 82 work head, 90 swing rod fixer.
DETAILED DESCRIPTION
Referring to the accompanying drawings it is seen that the invention, in the present embodiment, is structured to comprise: a loading and wrench claw 72 and accessories, serving to push the leather objects forward; a push speed, that is, push clearance adjustment unit 35 and accessories, serving to adjust the feeding speed of the leather objects; an advance recoiler 21, serving to lift claw 72 when it is desired to feed a series of leather objects for edging treatment by placing the object underneath claw 72; flanging member 66 and blade front 67 as shown in FIG. 1B, as provided below the vertical pressing stem 6, meant for press-setting edge fringe 122 and for cutting the same, as shown in FIG. 1C, in order to embellish the edging, or fringing of contoured or curved leather objects. A bending mound 3 having a cliffed face is provided in the direction into which leather products are provided on the operation board 4 relative to the mounting surface 8 and serves to guide a leather processing piece; a standing stem 12 controls support 14, as shown in FIG. 2, which bears ahead of the bending mound 3, and projects out of the access holes as provided on the mounting surface for the execution of up-and-down reciprocating movements, caused by the rotation of support 14, leading to the direction of movement of the front end of a leather object to be processed being in the same direction as the rotation of support 14.
Referring specifically to FIG. 1, it is seen that the belt wheel 10 is transmitted by means of a belt seated in groove 10a and driven by a power motor, not shown in the drawing. The belt wheel 10 in turn will drive camshaft 9 whose terminal end is provided with a cylindrical cam 11. Camshaft 9 also includes a curved sheave wheel 31 at its middle and an eccentric cam 7 provided at its front end. All these components will bring all the relevant components associated therewith, including claw 72, flanging member 66 and blade front 67, into synchronized or periodical movements once camshaft 9 is set to rotation. The activities of the transmission members are as follows:
As the cylindrical cam 11 at the terminal end of camshaft 9 rotates in synchronization with camshaft 9, it presses standing stem 12 discretely within the period of rotation. As a result, standing stem 12 presses against transverse guide stem 13 provided at the bottom of recovery spring 5c as shown in FIG. 2. The transverse guide stem 13 is fixed to the base of the mounting surface 8 by means of fix block 15 and rotates to force the radially extending support 14 over the operation board 4 through a hole or slot therein in order that the leather piece concerned may be guided in the direction of progression. Elbow 92 transmits the up and down motion of standing stem 12 into a restricted rotation of transverse guide stem 13. Connecting lever 13a connects transverse guide stem 13, through tube support 14a to radially extending support 14. The limited clockwise or counter-clockwise rotation of transverse guide stem 13 vertically displaces connecting lever 13a within slot 14b of tube 14a, which via its connection to radially extending support 14, causes that support 14 to move down and up, respectively.
When the camshaft 9 has rotated to a position so that cylindrical cam 11 is not in a position to bear against the standing stem 12, the standing stem 12 will then lift up to resume its initial status under the action of recovery spring 5c. In the meantime, the support 14 has moved downward into the hole or slot provided in the mounting surface 8, whereupon the curved sheave wheel 31 executes synchronized rotation together with camshaft 9 so that the curved groove 32 causes a swing rod 33 to execute a lateral swinging motion, as the flanging member 66 then drops to flat-press the flange or edge or fringe of the leather object, because extension arm 34 of the swing rod 33 is subject to sideways pushing force by curved groove 32 when it is set therein, as would appear apparent by reference to FIG. 2. An insertion pin 38 is provided in the middle of the swing rod 33 for bolting, in the capacity of a fulcrum, unto the fix block 90 for the machine body, so that the swinging of the top of swing rod 33 will cause the bottom thereof to swing sideways as well. From the terminal end of horizontal slide bar 51 there extends an axial arm 56 that will execute a horizontal reciprocating motion in the swing rod groove 39 in step with swing rod 33. The front of the slide bar 51 accommodates the fitting of a longitudinally set kettle 52, preferably about 3 cm in length, housing a wrench arm 73 above the wrench bar 71, the wrench arm 73 extending substantially radially from the wrench bar 71, the kettle 52 being united to the slide bar 51 at point 51a, kettle 52 and slide bar 51 together defining a horizontally extending arm, the wrench arm 73 being also united to the wrench bar 71. This arrangement causes the wrench bar 71 to execute a reciprocating rotation of less than 180° under the action of kettle 52 and wrench arm 73, due to the horizontal movement of slide bar 51. In turn, the claw 72 at the bottom of the wrench bar 71 executes a constant speed, reciprocating, progressive movement bringing an object leather piece to be fed into position, going short of 180°. The up-and-down movement of the claw 72 is further controlled by an active double bending shaft 40, as will be explained elsewhere in the text.
On the front tip of the cam shaft 9 there is provided an eccentric cam 7 with the shaft 7a thereof annexed to a swivel arm to carry the vertical pressing stem 6 into reciprocating longitudinal movements, so that a lowering of the pressing stem 6 causes a likewise lowering of the flanging member 66 at the bottom of pressing stem 6 to set-press the edging of a leather piece. When the press stem 6 lifts up, the claw 72, along with support 14, then positions the same leather piece for flat-setting. The outer rim of the eccentric cam 7, in the meantime, pushes against the vertical elbow lever 41 relative to the double bending shaft 40. The lateral displacement of the upper edge of vertical elbow lever 41 by eccentric cam 7, exerts torque upon double bending shaft 40 to rotate the same. The rotation of double bending shaft 40 in turn rotates affixed elbow segment 42. Horizontal elbow segment 42 extends from the double bending shaft 40, which passes behind the fix block 43 and is connected to a fix cap 75 attached to the top of the wrench bar 71. The rotation of elbow segment 42 causes vertical displacement of fix cap 75 and accordingly wrench bar 71. The wrench bar 71 is in its lowest position by the action of recovery spring 5b, as shown in FIG. 2, in the absence of the influence of the eccentric cam 7 via the vertical elbow lever 41 and the horizontal elbow segment 42. Concurrently, the slide bar 51 compels the kettle 52 to push the wrench arm 73 into rotation and thus cause the wrench bar 71 to rotate in conjunction with a downward movement in order that the wrench claw 72 in the course of progression, may feed the leather piece forward. Clockwise rotation of double bending shaft 40 lifts claw 72 in normal operation.
The advance recoiler 21, as shown in FIG. 1, functions mainly to lift up the wrench bar 71 outside the machine body as the operation begins. More exactly, advance recoiler 21 ensures that leather objects are cleared of the claw 72 and ready for automatic feeding, edging, and cutting operations once the motor is set at work. Activation of the advance recoiler 21 is done by stepping of operator's foot onto a pedal (not shown) provided at the bottom of a pull bar 24 outside the machine body whereupon the left end of lever 23 is pulled down, causing right end of lever 23 to lift the wrench arm 73 upward by virtue of fulcrum 22, to the effect that the wrench bar 71 as a whole will lift up to allow a leather piece to be fed to the underside of claw 72 with an edge thereof on the cliffed face of mound 3.
Wrench speed adjuster 35 adjusts the magnitude of the rotation angle of claw 72. A smaller angle results in a smaller wrenching clearance, and hence a shorter range in which the claw 72 is in a position to wrench an object leather piece to be fed in. However, at the same time, the flanging member 66, as shown in FIG. 1B, will have a better chance to flat-press the fringe 122 (also referred to herein as edge 122), as shown in FIG. 1C. On thee other hand, a larger rotation angle results in a larger wrenching clearance, and hence a longer range in which the claw 72 may be fed, similar to an increase in working speed. However, there will also be a wider and scattered distribution of the length of an edge-pressed leather piece. In the screw hole 36 of the wrenching adjuster 35 there is fitted a screw, not shown in the drawing, from a point outside the machine body, which serves to adjust the wrenching clearance from a point outside the machine body. From the adjustment lever 37 there extends, at a right angle, a shaft 130, as shown in FIG. 4B, for fitting with an annular piece 55 relative to the horizontal slide bar 51, as shown in FIG. 2, for facilitating the adjustment of the position of the horizontal slide bar 51 in the longitudinal axis, high or low. Against the same annular piece 55 there extends, at a right angle, a shaft 57 for setting in a slide groove 50a and through slide brace 55a relative to slide bar set dado 50, to enable an adjustment of the adjustment lever 37. Upward movement of adjustment lever 37 will be accompanied by an upward displacement of the slide bar 51, the slide bar shaft 56, and the kettle 52 without causing any horizontal displacement whatsoever. The terminal end of the slide bar 51, engaged in the spring rod groove 39 for the swing rod 33 will lift up as well, thus causing the front end of slide bar 51, in the form of a kettle 52, to rise up accordingly, therefore the kettle 52 will be in a position to drive to the wrench arm 73 by means of the underside 52a thereof. The driving will come from the top of the kettle 52 when the horizontal slide bar 51 drops to the lowest level, as shown in FIG. 1. Drive to the horizontal slide bar 51 comes from the swaying of swing rod 33. The raising of the horizontal slide bar 51 causes the slide bar shaft 56 to draw closer to the fulcrum 38 of swing rod 33 so that the amplitude of swinging diminishes, resulting in a narrower clearance of slide bar 51 in sideways displacement. Thus, the return angle of the wrench arm 73 rotatively driven by the kettle 52 in front of the slide bar decreases to result in a yet narrower clearance of the wrench claw 72 associated therewith. By like reasoning, if the adjustment lever 37 is forced downward by pressure to the position as shown in FIG. 1, so that the slide bar shaft 56 in the swing rod groove 39 accommodating the setting of the swing rod 33, relative to the horizontal slide bar 51, bears apart from the fulcrum point 38 on the swing rod 33, there results an enlarged swinging amplitude. Hence the sideways displacement of slide bar 51 increases, thus achieving the objective of speed adjustments.
The connector 80 located at the bottom of the work head 82 is furnished with a blade 67 such that the blade 67 will cut out a slit 123 as shown in FIG. 1C on edge 122 of a leather object 121 in moments when the vertical pressing lever 6 drops low. These slits 123 further facilitate edging and flanging treatments of leather objects at the folded corners. If such blade cutting is not required, then the adjustment knob may be turned to place the blade 67 into a rest position. This arrangement is much the same as ordinary mechanical switches and will not be dealt with in further detail.
As should be clear from the above description, claw 72 and radially extending support 14 grip between them the leather object to be edged and move the leftmost edge (i.e., the edge closest belt wheel 10) of the leather object across the cliffed face of bending mound 3, thus bending that edge. Once the leather object is properly positioned, claw 72 is rotated out of the way and into position to advance the leather object. Meanwhile vertical pressing stem 6 is forced downward, causing flanging member 66 to press against the bent edge of the leather object just beyond the cliffed face of bending mound 3, causing the leather object to be creased and flanged. Flanging is improved by the action of blade 67, which, by virtue of its sharpness and the downward force exerted by vertical pressing stem 6, cuts the edge of the leather object bent by the cliffed face, prior to flanging by member 66.
To place the machine of the present invention into operation, the motor is run to drive the belt wheel 10 so that all associated parts may be driven to work, the wrench bar 71 feeding leather objects, the vertical pressing stem 6 flat-pressing edges, fringes, and flanges of leather objects into formation, all done automatically. Of course, advance regulation of the cylindrical cam 11, curved sheath wheel 31, eccentric cam 7 relative to the cam shaft 9 should be made concurrent with the machine body in the installation stage. Their operation period in relation to one another should be such that the wrench bar 71 can secure a close coordination with the vertical pressing stem in operation. The recommended rotation speed of said motor is 1,300-1,800 r.p.m. The recommended clearance of reach by each round of activation of wrench claw 72 is 2.5-7 mm.
FIG. 11 shows that movement of wrench stem 71 is independent of head 80. Longitudinal movement of head 80, including attached blade 67 and flanged member 66 occurs as a result of longitudinal movement of pressing stem 6 (FIGS. 2 and 6).
When support tube 14 is in the down position, wrench stem 71, with claw 72 attached, lifts up and rotates counter-clockwise, while head 80 is in the up position. Tube 14 is raised and claw 72 moved downward and rotated clock-wise with wrench stem 71. Friction presented by support tube 14 and claw 72 as leather object 121 is grasped therebetween permits the clock-wise rotation of claw 72 to move the leather object in the direction indicated by the arrows of FIG. 11. Edge 122 is forced into and therefore bent upward by the cliffed face of bending mound 3. After this clock-wise rotation of wrench stem 71 and claw 72, wrench stem 71 and claw 72 are raised, while, at the same time, head 80, under the influence of vertical press stem 6, is lowered (FIG. 6).
Therefore, blade 67 cuts a slit into a portion of edge 122 which has passed just beyond bending mound 3, prior to flanging of that portion by flanging member 66 (FIGS. 1B and 11), creating slit 123, while flanging member 66 presses upon an already cut portion of edge 122 which, of course, is also beyond bending mound 3, to flange edge 122. On the next cycle, the above portion cut by blade 67 is flanged by flanging member 66 and a new portion of edge 122 is slit by blade 67.
Each recovery spring 5a-5f, simply permits the return of the respective element about which it is placed to an initial position from which the element has been disturbed and the recovery spring stretched or compressed by that disturbance.
The above disclosure fully supports the assertion that the present invention removes many of the shortcomings found with the use of conventional manual machines, devices, installations, or the like, by the provision of automatic edging processing capabilities. Modifications of the above-disclosed invention by those skilled in the art may be made without affecting the nature of the present invention and such modifications are intended to be within the scope of the appended claims. | An edging machine for leather products, particularly for the flanging as well as edging of the vamp or quarter of leather shoes or leatherette shoes, incorporates a cam shaft on which there are provided a cam, curved wheels and further eccentric cams which facilitate the automatic operation of a claw that progressively moves the leather product for flanging by a flanging member. Thus, the edging of leather products is accomplished at an improved product quality level as well as a cut in product cost as compared with conventional procedures. | 2 |
FIELD OF THE INVENTION
This invention relates generally to inventory control and, more specifically, to automated inventory control.
BACKGROUND OF THE INVENTION
Most prior inventory accounting methods have shortcomings at the input end. Often, inventory is initially taken manually. From then on, constant inventory accounting is maintained by accurate accounting of all transactions into and out of stock. However, that type of inventory accounting is slow, expensive, and requires meticulous acquisition and handling of inventory data. Often the inventory derived by the constant accounting of transactions into and out of stock is inaccurate because of unaccounted for transactions, spoilage, breakage, pilferage, improper identification of number or type of goods in stock, or for other reasons. Accordingly, means have been devised for accurately determining how many items are present at selected storage sites.
U.S. Pat. No. 4,419,734 issued Dec. 6, 1983 to Wolfson et al. is an example of a shelf weight sensing apparatus that analyzes solenoid signals produced by a weight sensor. The weight sensor is attached to a shelf in order to determine the precise number of inventory items located on the specified shelf. This type of system is expensive because it requires extensive circuitry for analyzing the signals received from multiple weight sensors. In addition, this type of system is made for stationary shelving systems which is not conducive to other forms of inventory storage and control.
Therefore, there exists an unmet need to provide a low-cost weight sensing inventory control system for moveable shelves or drawers.
SUMMARY OF THE INVENTION
The present invention provides systems and methods for automatically reordering parts thereby providing inventory control. In one embodiment, a system includes a tray adapted to support a plurality of parts, and a resilient member operatively engaged with the tray and adapted to flex according to the weight of parts stored on the tray. A switch generates a signal when the amount of parts on the tray is less than a predefined amount. A central processing unit coupled to the switch receives the signal generated by the switch and automatically reorders parts based on the received signal from the switch.
In one aspect of the invention, the resilient member includes a leaf spring or a helical spring. In another aspect of the invention, the tray is a slidable drawer having a floor supported by the resilient member. The switch engages one of the floor or the resilient member under a first weight condition and disengages with one of the floor or resilient member under a second weight condition. The first weight condition is greater than the second weight condition.
In a further aspect of the invention, a slidable rail structure supports the drawer and the resilient member supports the rail structure. The switch engages one of the rail structure or resilient member under a first weight condition and disengages one of the rail structure or resilient member under a second weight condition. The first weight condition is greater than the second weight condition.
BRIEF DESCRIPTION OF THE DRAWINGS
The preferred and alternative embodiments of the present invention are described in detail below with reference to the following drawings.
FIG. 1 illustrates a block diagram of an example system formed in accordance, with an embodiment of the present invention;
FIG. 2 illustrates a flow diagram of an example process performed by the system shown in FIG. 1 in accordance with an embodiment of the present invention; and
FIGS. 3 , 4 , 5 A-C, 6 , and 7 illustrate various embodiments of weight sensors incorporated into a storage unit.
DETAILED DESCRIPTION OF THE INVENTION
The present invention is directed to systems and methods for providing automatic inventory tracking of materials stored in moveable shelves or drawers. Many specific details of certain embodiments of the invention are set forth in the following description and in FIGS. 1-5 to provide a thorough understanding of such embodiments. One skilled in the art, however, will understand that the present invention may have additional embodiments, or that the present invention may be practiced without several of the details described in the following description.
In one embodiment, the present invention is an automated inventory control system that uses movable weight sensing shelves or drawers for providing inventory trigger signals based on a sensed weight of a shelf or a drawer that stores an inventory of parts. FIG. 1 illustrates an exemplary computer-based system 20 that automatically performs inventory sensing and automatic reordering based on a sensed inventory. The system 20 includes a plurality of weight sensors 24 located in conjunction with slidable shelves or drawers that are operatively coupled to a central processing unit (CPU) 30 . The CPU 30 is connected to memory 34 and to a supply system 32 over a public or private data network 36 . It will be appreciated that the CPU 30 may communicate in various other ways, such as, without limitation, by facsimile or electronic mail, with the supply system 32 .
FIG. 2 illustrates an exemplary method 40 performed by the system 20 ( FIG. 1 ) in accordance with an embodiment of the invention. First, at block 42 , each weight sensor 24 may generate a signal when the sensed weight of parts, materials, goods, etc. in the respective shelf falls below a predefined threshold amount. Next, at block 44 , the generated signal is sent to the CPU 30 . At block 46 , the CPU 30 identifies the part or parts that are associated with the weight sensor 24 that generated and sent the signal. In one embodiment, the CPU 30 may use information stored within the memory 34 to identify the part stored on the shelf or drawer associated with the weight sensor 24 . For example, the CPU 30 determines the part that is associated with the weight sensor 24 by comparing the identifier to a list or table previously stored in the memory 34 . In another embodiment, an identifier may be included in the signal generated by the weight sensor 24 . Next, at block 48 , the CPU 30 may inform inventory control personnel that the part within the shelf or drawer that is associated with the weight sensor 24 that generated and sent the signal is low. The CPU 30 may automatically request a re-order for the part associated with the shelf or drawer at block 49 via the network 36 , email, fax, etc. It will be appreciated that the CPU 30 can perform ordering in a number of ways, including, for example, by sending a message directly to a re-supplier or the supply system 32 over the network 36 .
In an alternate embodiment, the weight sensor 24 activates a light or some other indicator (visual or audible) at the shelf or drawer or at a central location for providing a visual indication of the need for restocking/re-ordering to an employee.
FIG. 3 illustrates a cross-sectional view of an exemplary inventory storage shelf 50 in accordance with another embodiment of the present invention. The shelf 50 includes a storage area 52 that is formed by sidewalls 54 and a weight sensing floor 56 . The weight sensing floor 56 is supported by a leaf spring 60 . The leaf spring 60 allows the weight sensing floor 56 to move within the storage area 52 based on the amount of weight the weight sensing floor 56 supports. The weight sensing floor 56 is preferably not permanently attached to any of the sidewalls 54 . In this embodiment, a switch 62 is positioned underneath the weight sensing floor 56 . The switch 62 maintains contact with the leaf spring 60 or the weight sensing floor 56 as long as the weight of the parts supported by the weight sensing floor 56 is greater than a threshold amount. If the weight of the items on the weight sensing floor 56 falls below the threshold amount, in other words the number of parts within of the shelf 50 is below a threshold amount, the leaf spring 60 forces the weight sensing floor 56 away from the switch 62 thereby toggling or triggering the switch 62 . The toggled switch 62 sends a signal to the CPU 30 . For example, if the shelf 50 includes a number of two-ounce bolts and the user wants the shelf 50 to begin a re-supply activity when there are only eight bolts left within the shelf 50 , then the type of leaf spring 60 is selected so it forces the weight sensing floor 56 away from the switch 62 when only a pound of parts (16 oz.) remains.
FIG. 4 illustrates a cross-sectional view of an exemplary inventory storage shelf 80 that includes a helical spring 84 and a switch 82 in accordance with yet another embodiment of the present invention. The helical spring 84 supports a weight sensing floor 86 similar in manner to the leaf spring 60 ( FIG. 3 ) described above. The switch 82 is coupled to the CPU 30 and operates similarly to the switch 62 ( FIG. 3 ). It will be appreciated that other devices may be used for creating weight induced movement within the shelves 50 or 80 .
FIG. 5A illustrates a cross-sectional view of a slidable shelf 90 connected to a rail system 94 in accordance with another embodiment of the present invention. The rail system 94 allows the shelf 90 to slide within a larger cabinet or frame structure (not shown). FIGS. 5B and 5C illustrate further embodiments of the rail system 94 . As shown in FIG. 5B , a helical coil 100 is connected to a support structure 102 and a base portion 104 of the rail system 94 . The base portion 104 is a stationary part (bottom rail) of the rail system 94 . A top rail (not shown) is slideably received by the base portion 104 and is attached to the shelf 90 . In one representative embodiment, the support structure 102 may be a cabinet. A horizontally sliding portion (not shown) of the rail system 94 supports the shelf 90 and is slideably received by the base portion 104 . A switch 120 is positioned between the base portion 104 and the structure 102 . The spring 100 and switch 120 operate similarly to those in the shelves 50 and 80 ( FIGS. 3 and 4 ).
As shown in FIG. 5C , in another alternate embodiment, a leaf spring 110 may be used to support the base portion 104 with respect to the structure 102 . A switch 122 is positioned between the base portion 104 and structure 102 . The spring 110 and switch 122 operate similarly to those in the shelves 50 and 80 ( FIGS. 3 and 4 ). It will be appreciated that in further embodiments, the leaf and coil springs shown in FIGS. 3-5 may be replaced with a variety of other resilient members, including, for example, rubber or other polymeric compressible members, hydraulic or pneumatic cylinders, or any other suitable resilient members.
As shown in FIGS. 6 and 7 , switches operate by being depressed with lighter weight on a shelf. The rail structure can be configured to perform the same function.
While the preferred embodiment of the invention has been illustrated and described, as noted above, many changes can be made without departing from the spirit and scope of the invention. Accordingly, the scope of the invention is not, limited by the disclosure of the preferred embodiment. Instead, the invention should be determined entirely by reference to the claims that follow. | Systems and methods for automatically reordering parts are disclosed. In one embodiment, a system includes a tray adapted to support parts, and a resilient member operatively engaged with the tray that flexes according to the weight of parts stored on the tray. A switch generates a signal when the amount of parts on the tray is less than a predefined amount. A central processing unit coupled to the switch receives the signal generated by the switch and automatically reorders parts based on the received signal from the switch. | 6 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part application claiming priority from U.S. patent application Ser. No. 09/990,031 filed on Nov. 21, 2001, the specification and drawings of which are incorporated herein by reference.
BACKGROUND OF INVENTION
[0002] This invention generally relates to imaging for the purpose of medical diagnosis. In particular, the invention relates to methods for imaging tissue and blood flow by detecting ultrasonic echoes reflected from a scanned region of interest in a human body.
[0003] Conventional ultrasound scanners are capable of operating in different imaging modes. In the B mode, for example, two-dimensional images can be generated in which the brightness of each display pixel is derived from the value or amplitude of a respective acoustic data sample representing the echo signal returned from a respective focal position within a scan region.
[0004] In B-mode imaging, an ultrasound transducer array is activated to transmit beams focused at respective focal positions in a scan plane. After each transmit firing, the echo signals detected by the transducer array elements are fed to respective receive channels of a receiver beam-former, which converts the analog signals to digital signals, imparts the proper receive focus time delays and sums the time-delayed digital signals. For each transmit firing, the resulting vector of raw acoustic data samples represents the total ultrasonic energy reflected from a succession of ranges along a receive beam direction. Alternatively, in multi-line acquisition two or more receive beams can be acquired following each transmit firing.
[0005] In conventional B-mode imaging, each vector of raw acoustic data samples is envelope detected and the resulting acoustic data is compressed (e.g., using a logarithmic compression curve). The compressed acoustic data is output to a scan converter, which transforms the acoustic data format into a video data format suitable for display on a monitor having a conventional array of rows and columns of pixels. This video data is typically referred to as “raw pixel intensity values”. The frames of raw pixel intensity data are mapped to a gray scale for video display. Each gray-scale image frame, typically referred to as “gray-scale pixel intensity values”, is then sent to the video monitor for display. In the case where a one-to-one gray-scale mapping is in effect, the raw and gray-scale pixel intensity values will be one and the same.
[0006] While a number of image processing parameters may control the final image presentation, it is often difficult to determine which of these parameters, or which combination of the parameters, may be adjusted to provide the optimal image presentation. Often, the image processing techniques must be adjusted in accordance with empirical feedback from an operator, such as a physician or technician.
[0007] The facility with which a reconstructed discrete pixel image may be interpreted by an observer may rely upon intuitive factors of which the observer may not be consciously aware. For example, in medical diagnostic ultrasound imaging, a physician or radiologist may seek specific structures or specific features in an image such as bone, soft tissue or fluids. Such structures may be physically defined in the image by contiguous edges, contrast, texture, and so forth.
[0008] The presentation of such features often depends heavily upon the particular image processing technique employed for converting the detected values representative of each pixel to modified values used in the final image. The image processing technique employed can therefore greatly affect the ability of an observer or an analytical device to recognize salient features of interest. The technique should carefully maintain recognizable structures of interest, as well as abnormal or unusual structures, while providing adequate textural and contrast information for interpretation of these structures and surrounding background. Ideally the technique will perform these functions in a computationally efficient manner so that processing times, as well as hardware requirements, can be minimized.
[0009] In ultrasound imaging, acquired images can be corrupted by slowly varying multiplicative inhomogeneities or non-uniformities in spatial intensity. Such non-uniformities can hinder visualization of the entire image at a given time, and can also hinder automated image analysis. When the image is corrected for non-uniformity alone, noise in the dark regions of the original image becomes multiplicatively enhanced thereby providing an unnatural look to the image. Such images are usually not preferred by radiologists.
[0010] There is a need for a computationally efficient method of pre-filtering ultrasound images in real time to reduce noise prior to the performance of additional image enhancement steps such as non-uniformity equalization and contrast enhancement.
SUMMARY OF INVENTION
[0011] The invention is directed to improving ultrasound images by means of image filtering. The image filtering is especially useful in combination with subsequent image enhancement steps, namely, non-uniformity equalization and contrast enhancement, but the image filtering process of the invention is independent of the subsequent image enhancement processes utilized.
[0012] The invention provides an improved technique for enhancing discrete pixel ultrasound images which is computationally efficient and which maintains image quality. The technique combines multi-resolution decomposition with a segmentation-based technique that identifies structures within an image and separately processes the pixels associated with those structures. This combination exploits the redundancies of an image while also allowing the separate processing of structures and non-structures.
[0013] Because of the efficiency of the disclosed technique, real-time or near real-time ultrasound imaging may be performed without utilizing hardware-based noise reduction techniques that can result in degraded, inferior images. In an exemplary embodiment, multi-resolution decomposition occurs when an input is shrunk by a given factor, allowing for the exploitation of redundancies in the image during subsequent processing. The shrunken image is then processed using a segmentation-based technique that begins by identifying the structural elements within a blurred or smoothed image. The segmentation is based on both gradient threshold and the distance from the near field. This segmentation processing renders the structural details more robust and less susceptible to noise and selectively suppresses near-field artifacts. While small, isolated regions may be filtered out of the image, certain of these may be recovered to maintain edge and feature continuity.
[0014] Following identification of the structures, portions of the image, including structural and non-structural regions, are smoothed. Structural regions are smoothed to enhance structural features in dominant orientations, thereby providing consistency both along and across structures. Non-structural regions may be homogenized to provide an understandable background for the salient structures.
[0015] Upon completion of the segmentation-based processing, the image is expanded by the same factor used during shrinking, thereby returning the image to its original size. Original texture is then added back to non-structural regions by blending to further facilitate interpretation of both the non-structural and structural features. In addition, a small predetermined fraction of intensity-dependent, uniform random noise is added to the non-structure region pixels whose intensities are above a predetermined intensity threshold, thereby mitigating ultrasound speckle in the expanded image while leaving non-echogenic subregions of the non-structure region undisturbed.
[0016] One aspect of the invention is an ultrasound imaging system comprising a data acquisition system for acquiring acoustic data, an image processor for converting acoustic data into a set of pixel intensity values for each image, a display monitor for displaying images, and a computer programmed to perform the following steps: (a) shrinking an initial image by a predetermined factor to produce a shrunken image; (b) creating a first binary mask as a function of whether pixels of the shrunken image have gradients greater than a gradient threshold and locations more than a predetermined distance from a near field in the shrunken image; (c) filtering pixels corresponding to structural components in the shrunken image in accordance with a first filtering algorithm, the structural components being identified by the first binary mask; (d) filtering pixels corresponding to non-structural components in the shrunken image in accordance with a second filtering algorithm different than the first filtering algorithm, the non-structural components being identified by the first binary mask (e) expanding the filtered image and the first binary mask by the predetermined factor to produce an expanded image and a first expanded binary mask; (f) blending one or more selected regions of the expanded image with a corresponding region or regions of the initial image, the blending being a function of the first binary mask; (g) adding uniform random noise to one or more selected echogenic non-structural regions of the expanded image; and (h) outputting a final image to the display monitor, the final image being derived by performing at least steps (a) through (h).
[0017] Another aspect of the invention is a method for filtering an ultrasound image, comprising the following steps: (a) shrinking an initial image by a predetermined factor to produce a shrunken image; (b) creating a first binary mask as a function of whether pixels of the shrunken image have gradients greater than a gradient threshold and locations more than a predetermined distance from a near field in the shrunken image; (c) filtering pixels corresponding to structural components in the shrunken image in accordance with a first filtering algorithm, the structural components being identified by the first binary mask; (d) filtering pixels corresponding to non-structural components in the shrunken image in accordance with a second filtering algorithm different than the first filtering algorithm, the non-structural components being identified by the first binary mask (e) expanding the filtered image and the first binary mask by the predetermined factor to produce an expanded image and a first expanded binary mask; (f) blending one or more selected regions of the expanded image with a corresponding region or regions of the initial image, the blending being a function of the first binary mask; and (g) adding uniform random noise to one or more selected echogenic non-structural regions of the expanded image to form a final image suitable for display or further image enhancement.
[0018] A further aspect of the invention is an ultrasound image filter comprising: means for shrinking an initial image by a predetermined factor to produce a shrunken image; means for orientation smoothing pixels corresponding to structural components in the shrunken image; means for iteratively low-pass filtering pixels corresponding to non-structural components in the shrunken image; means for expanding the filtered image by the predetermined factor to produce an expanded image; means for blending one or more selected regions of the expanded image with a corresponding region or regions of the initial image, the blending being a function of whether the corresponding pixel of the shrunken image has a gradient greater than a gradient threshold and a location more than a predetermined distance from a near field in the shrunken image; and means for adding uniform random noise to one or more selected echogenic non-structural regions of the expanded image to form a final image suitable for display or further image enhancement.
[0019] Yet another aspect of the invention is a method for filtering an ultrasound image, comprising the following steps: shrinking an initial image by a predetermined factor to produce a shrunken image; orientation smoothing pixels corresponding to structural components in the shrunken image; iteratively low-pass filtering pixels corresponding to non-structural components in the shrunken image; expanding the filtered image by the predetermined factor to produce an expanded image; blending one or more selected regions of the expanded image with a corresponding region or regions of the initial image, the blending being a function of whether the corresponding pixel of the shrunken image has a gradient greater than a gradient threshold and a location more than a predetermined distance from a near field in the shrunken image; and adding uniform random noise to one or more selected echogenic non-structural regions of the expanded image to form a final image suitable for display or further image enhancement.
[0020] A further aspect of the invention is a method for mitigating speckle in an ultrasound image, comprising the following steps: creating a binary mask having a first value binary value for each pixel of an image that satisfies a first condition of having a gradient greater than a gradient threshold and a second condition of having an intensity greater than a predetermined intensity level, and a second binary value for each pixel that does not meet both the first and second conditions; and adding uniform random noise to each pixel of the image that corresponds to a pixel in the binary mask having the first binary value and not adding noise to other pixels of the image.
[0021] Another aspect of the invention is an ultrasound imaging system comprising a data acquisition system for acquiring acoustic data, an image processor for converting acoustic data into a set of pixel intensity values for each image, a display monitor for displaying images, and a computer programmed to perform the following steps: (a) creating a binary mask having a first value binary value for each pixel of an image that satisfies a first condition of having a gradient greater than a gradient threshold and a second condition of having an intensity greater than a predetermined intensity level, and a second binary value for each pixel that does not meet both the first and second conditions; (b) adding uniform random noise to each pixel of the image that corresponds to a pixel in the binary mask having the first binary value and not adding noise to other pixels of the image; and (c) outputting a final image to the display monitor, the final image being derived by performing at least steps (a) and (b).
[0022] Other aspects of the invention are disclosed and claimed below.
BRIEF DESCRIPTION OF DRAWINGS
[0023] [0023]FIG. 1 is a block diagram generally showing a typical B-mode ultrasound imaging system.
[0024] [0024]FIG. 2 is a diagram of an exemplary discrete pixel image made up of a matrix of pixels having varying intensities defining structures and non-structures.
[0025] [0025]FIG. 3 is a flowchart illustrating the progression of an image through multi-resolution decomposition and segmentation-based processing.
[0026] [0026]FIG. 4 is a flowchart illustrating steps in exemplary control logic for multi-resolution decomposition of a discrete pixel ultrasound image, identification of structures in that image and enhancement of both structural and non-structural regions in the image.
[0027] [0027]FIG. 5 is a schematic showing exemplary near and far fields in a sector-shaped ultrasound image.
DETAILED DESCRIPTION
[0028] Referring to FIG. 1, a B-mode ultrasound imaging system typically comprises a transducer array 2 , a beamformer 4 , a B-mode image processor 6 , a host computer 8 and a display monitor 10 . The transducer array 2 comprises a multiplicity of transducer elements which are activated by a transmitter in beamformer 4 to transmit an ultrasound beam focused at a transmit focal position. The return RF signals are detected by the transducer elements and then dynamically focused at successive ranges along a scan line by a receiver in beamformer 4 to form a receive vector of raw acoustic data samples. The beamformer output data (I/Q or RF) for each scan line is passed through a B-mode image processor 6 , which processes the raw acoustic data into pixel image data in a format suitable for display by the display monitor 10 .
[0029] System control is centered in a host computer 8 , which accepts operator inputs through an operator interface (not shown), analyzes the acquired data and controls the various subsystems based on operator inputs and the results of data analysis. The host computer 8 may be programmed to perform the following functions: (1) providing transmit and beamforming parameters to the beamformer 4 ; (2) providing gray mappings to the B-mode image processor 6 ; (3) retrieving an image frame from memory, re-scaling that image frame and then sending the re-scaled image to the display monitor for display in a zoom mode; and (4) providing data compression curves to the B-mode image processor 6 . Preferably, the gray map, beamforming parameters and compression curves are provided in the form of lookup tables stored in random access memory. Although FIG. 1 depicts separate paths for the communications to and from the host computer 8 , it will be readily appreciated that these communications may take place over a common channel or system bus.
[0030] In an ultrasound image acquisition system, usually significant care is taken to sample the data at a frequency that is at least twice the highest spatial frequency of interest. In many cases, potential problems are avoided by over-sampling. However, while visualizing an ultrasound image, variations from pixel to pixel due to acquisition noise, which is usually random, can be seen. In most image acquisition systems, additional structured noise (i.e., artifacts) will be present. In accordance with one embodiment of the present invention, the host computer 8 of the ultrasound imaging system depicted in FIG. 1 may be programmed to retrieve successive image frames of raw pixel intensity data from image processor 6 and then perform image filtering computations to reduce noise.
[0031] In order to mitigate random noise, many noise reduction filters have been proposed. Many of them use multi-resolution decomposition (e.g., wavelet-based techniques), which decomposes the image into various frequency bands, processes each band separately and then regroups all the frequency bands together to reconstitute the image. This class of techniques has the advantage of modifying a specific spatial frequency band of the image. A well-known corollary of these techniques in image compression is that substantially all the redundancies at a given scale are exploited to achieve high compression ratios without sacrificing the compression quality in these images. Another class of filters is segmentation-based. This class of techniques decomposes the image based on structures and non-structures, processes structures and non-structures separately and then recombines the processed structures and non-structures to form the final filtered image. Unlike in the previous case, this class of methods exploits the spatial connectedness of structures to substantially perform different operations on structures and non-structures.
[0032] [0032]FIG. 2 illustrates an exemplary image 50 composed of a matrix of discrete pixels 52 disposed adjacent to one another in a series of rows 54 and columns 56 . These rows and columns of pixels provide a pre-established matrix width 58 and matrix height 60 . Typical matrix dimensions may include 256×256 pixels; 512×512 pixels; 1,024×1,024 pixels, and so forth. The particular image matrix size may be selected via an operator interface (not shown in FIG. 1) and may vary depending upon such factors as the subject to be imaged and the resolution desired.
[0033] As seen in FIG. 2, exemplary image 50 includes structural regions 62 , illustrated as consisting of long, contiguous lines defined by adjacent pixels. Image 50 also includes non-structural regions 64 lying outside of structural regions 62 . Image 50 may also include isolated artifacts 66 of various sizes (i.e., varying number of adjacent pixels), which may be defined as structural regions, or which may be eliminated from the definition of structure in accordance with the techniques described below. It should be understood that the structures and features of exemplary image 50 are also features of the specific and modified images discussed below in relation to FIGS. 3 and 4.
[0034] A highly abstracted rendition of image filtering in accordance with one embodiment of the invention is illustrated in FIG. 3, beginning with the input of the raw signal data as input image 70 (I raw ). Input image 70 is shrunk by a user-raw configurable parameter (interp) to create a shrunken image 72 (I shrunk ). Shrunken image 72 undergoes normalization to create a normalized image 74 (I normal ). Threshold criteria are applied to identify structures within the normalized image 74 . The structures identified are used to generate a structure mask 76 (M structure ) that is used in subsequent processing to distinguish both structure and non-structure regions, allowing differential processing of these regions. The mask is based on both gradient threshold and the distance of the pixel from the near field. This is to selectively suppress near-field artifacts. The normalized image 74 is filtered to reduce noise via structure mask 76 , thereby creating an intermediate filtered image 78 (I filtered ) that is subsequently normalized by scaling to form renormalized image 80 (I renormal ). Renormalized image 80 and structure mask 76 are expanded to form an expanded image 82 (I expanded ) and an expanded structure mask 83 (M expanded ). Differential blending of the expanded image 82 and the input image 70 is accomplished via the application of the expanded structure mask 83 . In addition, a small predetermined fraction of intensity-dependent, uniform random noise is added to pixels corresponding to the echogenic subregions of the nonstructure region. The purpose of noise addition is to mitigate ultrasound speckle. The product of the blending process is final filtered image 84 (I final ).
[0035] In accordance with method disclosed herein, the redundancy exploitation of multi-resolution-based techniques is combined with the spatial connectedness of the segmentation-based techniques to obtain a robust noise reduction with computationally efficient implementation. More specifically, in one embodiment of the invention, the host computer (or dedicated processor) of an ultrasound imaging system performs a noise-reduction filtering algorithm. One embodiment of this algorithm is generally depicted in FIG. 4. This algorithm comprises efficient real-time computations for mitigating noise based on structures, providing improved image quality at reduced cost, by replacing hardware-based noise reduction techniques that are being used to achieve real-time performance but at reduced image quality.
[0036] The first step 120 in the algorithm is to read the input data and the parameters that control the filtering. The parameters include the following: amount of shrinking (interp), interpolation type (interpMode), parameters specific to noise reduction (Focus, Edge, EdgeThreshold, Blend, edgeBlend). Parameter interp is usually set equal to 2, but higher values can be used to obtain faster implementations if moderate amounts of noise reduction would be sufficient for the given application. The other parameters can be tuned based on the domain knowledge of the radiologist/radiological technician. By means of this selection of shrinking parameter, specialized tuning for larger matrix images is not required and therefore, the otherwise laborious tuning process is simplified to a large extent.
[0037] In the preprocessing step 121 , the size of the input raw image I raw is augmented to prevent loss of data when images are shrunk. Since the shrink (.) function requires integer values for performing data reduction, image boundaries are appropriately padded by mirroring the image data.
[0038] In step 122 , the preprocessed input images are shrunk as determined by the parameter interp. The shrink (.) function uses average intensity values in non-overlapping integer neighborhoods of size interp X interp and creates a shrunken image I shrunk . However, other sub-sampling techniques can be used.
[0039] Still referring to FIG. 4, the next step 126 is to normalize the pixel intensities of the shrunken image to form a normalized image I normal . This step includes reading digital values representative of each pixel intensity and scaling those intensities over a desired dynamic range. First, internal parameters are initialized. These parameters include the following: iter_number2=10, length=3, areaPercent=0.95, follower_ratio=0.5, gradAngle=0.35, count_threshold1=2, count_threshold2=2. Second, the maximum (MAX_ORIGINAL) and minimum (MIN_ORIGINAL) intensity values are determined. Third, the scale is set equal to 4095.0/MAX_ORIGINAL. Fourth, the scaled image I normal is obtained using the relation: I=(I−MIN_ORIGINAL)*scale. Fifth, the pre-filtration image is saved as I 1 =I. Sixth, compute the average intensity value (MEAN_BEFORE) of 1. The main reason for scaling is to make the filtering effect independent of the dynamic range and the DC offset of the data.
[0040] The next step 126 in the algorithm is to extract structures and non-structures from a given normalized image, as defined by data representative of the individual pixels of the image. This is accomplished by determining structure and non-structure masks. The following steps are used for this purpose.
[0041] In the first step, a gradient image is computed from a blurred or smoothed version of the normalized original image. A boxcar smoothing is used in the preferred method. A boxcar filter smoothes an image by computing the average of a given neighborhood. The kernel is separable and efficient methods exist for its computation. The length of the separable kernel is variable (parameter length) but preferably set equal to 3 pixels. The kernel is moved horizontally and vertically along the image until each pixel has been processed.
[0042] In the second step, the edge strength threshold is computed automatically from the image by means of the following computations.
[0043] (1) At every pixel, compute the X gradient component componentX, the Y gradient component componentY and the resultant gradient as the maximum of the two components. Compute the direction of the gradient using arctan (componentY/componentX).
[0044] More specifically, the X and Y gradient components for each pixel are computed based upon the smoothed version of the normalized image. While several techniques may be employed for this purpose, 3×3 Sobel modules or operators can be employed. As will be appreciated by those skilled in the art, one module is used for identifying the X gradient component, while another module is used for identifying the Y gradient component of each pixel. In this process, the modules are superimposed over the individual pixel of interest, with the pixel of interest situated at the central position of the 3×3 module. The intensity values located at the element locations within each module are multiplied by the scalar value contained in the corresponding element, and the resulting values are summed to arrive at the corresponding X and Y gradient components.
[0045] With these gradient components thus computed, the gradient magnitude G mag and gradient direction G dir are computed. The gradient magnitude for each pixel is equal to the higher of the absolute values of the X and Y gradient components for the respective pixel. The gradient direction is determined by finding the arctangent of the Y component divided by the X component. For pixels having an X component equal to zero, the gradient direction is assigned a value of π/2. The values of the gradient magnitudes and gradient directions for each pixel are saved in memory.
[0046] It should be noted that alternative techniques may be employed for identifying the X and Y gradient components and for computing the gradient magnitudes and directions. For example, those skilled in the art will recognize that in place of Sobel gradient modules, other modules such as the Roberts or Prewitt operators may be employed. Moreover, the gradient magnitude may be assigned in other manners, such as a value equal to the sum of the absolute values of the X and Y gradient components.
[0047] (2) Create the gradient histogram and use the 30 percentile value as an initial gradient threshold (IGT).
[0048] More specifically, based upon the gradient magnitude values, a gradient histogram is generated. The histogram is a bar plot of specific populations of pixels having specific gradient values. These gradient values are indicated by positions along a horizontal axis, while counts of the pixel populations for each value are indicated along a vertical axis, with each count falling at a discrete level. The resulting bar graph forms a step-wise gradient distribution curve. Those skilled in the art will appreciate that in the actual implementation, the histogram need not be represented graphically, but may be functionally determined by the image processing circuitry operating in cooperation with values stored in memory circuitry.
[0049] The histogram is used to identify a gradient threshold value for separating structural components of the image from non-structural components. The threshold value is set at a desired gradient magnitude level. Pixels having gradient magnitudes at or above the threshold value are considered to meet a first criterion for defining structure in the image, while pixels having gradient magnitudes lower than the threshold value are initially considered non-structure. The threshold value used to separate structure from non-structure is preferably set by an automatic processing or “autofocus” routine. However, it should be noted that the threshold value may also be set by operator intervention (e.g., via an operator interface) or the automatic value identified through the process described below may be overridden by the operator to provide specific information in the resulting image.
[0050] The process for identification of the threshold value begins by selecting an initial gradient threshold. This initial gradient threshold is conveniently set to a value corresponding to a percentile of the global pixel population, such as 30 percent. The location along the histogram horizontal axis of the IGT value is thus determined by adding pixel population counts from the left-hand edge of the histogram, adjacent to the vertical axis and moving toward the right (i.e., ascending in gradient values). Once the desired percentile value is reached, the corresponding gradient magnitude is the value assigned to the IGT.
[0051] (3) In the next step, a search is performed for edges of the desired structure. In a neighborhood of a pixel whose gradient is greater than the IGT, count the number of pixels which have gradient magnitudes above IGT and whose gradient directions do not differ from the center pixel more than a predetermined angle (parameter gradAngle). If the count is greater than a predetermined threshold, include the current pixel as a relevant edge.
[0052] (4) In the next step, small or noisy segments identified as potential candidates for structure are iteratively eliminated by isolating small segments less than a predetermined count using an eight-connected connectivity approach. Alternatively, a four-connected connectivity approach can be used.
[0053] (5) Count the number of edge pixels obtained as a result and add a fuzzy constant to their number to get a final number N.
[0054] (6) From the gradient histogram, compute the final gradient threshold (FGT), which corresponds to the gradient above which there are N gradient counts.
[0055] An algorithm to efficiently remove small islands of high-gradient segments is carried out using a connectivity approach as follows: (a) Obtain a binary image by thresholding the image based on a gradient value.
[0056] (b) Start a labeling process on a line-by-line basis while incrementing the label index.
[0057] (c) Merge the connected labels using the four-connected or eight-connected rule by replacing the current label with the lowest index in the neighborhood. This is done in an iterative fashion by scanning the binary image top to bottom and bottom to top until there are no more regions to be merged or a predetermined number of iterations are exceeded.
[0058] (d) Obtain the histogram of indices.
[0059] (e) Find those index bins that are lower than a predetermined number and set the corresponding pixel in the binary image equal to zero.
[0060] The resultant binary image would be the mask, which does not include small segments of high-gradient regions.
[0061] In the third step, after the FGT has been obtained, it is scaled by multiplying with a user-selected parameter, Focus (e.g., 2.0). In the fourth step, a binary mask image M structure1 is created such that the pixels are set to 1 if the corresponding pixels in the gradient image (a) have a gradient greater than FGT and (b) are located beyond a pre-specified distance from the near field An exemplary near field in a typical sector scan ultrasound image 48 is shown in FIG. 5. Otherwise the mask is set to 0.
[0062] In the fifth step, a second binary mask image M structure2 is created such that the pixels are set to 1 if the corresponding pixels in the gradient image are higher than the pre-specified gradient threshold FGT and if the corresponding pixels in the initial intensity image are higher than a pre-specified intensity threshold. This is done only for pixels located beyond the pre-specified distance from the near field.
[0063] In the sixth step, isolated small segments in the binary image less than a predetermined count are eliminated using a four-connected connectivity approach. The resultant binary image is a mask that includes significant high-gradient regions but is devoid of small islands of high-gradient regions.
[0064] In the seventh step, certain of the isolated regions may be recuperated to provide continuity of edges and structures using a gradient following approach. If the pixel in the gradient image is above a threshold (GFT), which is a predetermined percentage (parameter follower_ratio) of FGT, and is connected to a pixel that is above FGT, then the corresponding pixel in the binary image from the previous step is changed from 0 to 1. This gradient following is usually carried out recursively and at the end an initial classification of pixels is obtained.
[0065] In the eighth step, the feature edges identified through previous steps, representative of candidate structures in the image, are binary rank order filtered to expand and define the appropriate width of contiguous features used to define structural elements. Simplistically, if the current mask pixel is 1, the neighborhood (e.g., 3×3) pixel count is computed. If the pixel count is below a countThreshold1 (e.g., 2), then the current mask pixel is set to 0. If the current mask pixel is 0, the neighborhood (e.g., 3×3) pixel count is computed. If the pixel count is above a countThreshold2 (e.g., 2), then the current mask pixel is set to 1. In each neighborhood count, pixels in the binary mask having values of 1 are counted within a 3×3 neighborhood surrounding the structural pixel of interest. This count includes the pixel of interest. The resulting structure mask M structure1 contains information identifying structural features of interest and non-structural regions. Specifically, pixels in structure mask M structure1 having a value of 1 are considered to identify structure, while pixels having a value of 0 are considered to indicate non-structure. This completes the structure identification step 126 seen in FIG. 4.
[0066] After structure in the image has been identified, the structure undergoes anisotropic smoothing (step 128 ) followed by anisotropic sharpening (step 132 ). In parallel with anisotropic smoothing of the structure identified within the image, isotropic smoothing of non-structure is performed (step 130 ). The details of these steps are as follows.
[0067] The anisotropic smoothing comprises conventional orientation smoothing. A region with structures is filtered to extract dominant orientation. The method involves iteratively filtering the structure by a 3×1 smoothing kernel along the dominant direction in a given neighborhood, which would be the direction of majority of the local minimum variances in that neighborhood. This process has the tendency to bridge gaps and the amount is controlled by a parameter. The iterations are performed a set number of times (e.g., 3).
[0068] Each iteration is accomplished using the following steps. The structure region is scanned and a local orientation map is obtained by assigning one of four orientation numbers, i.e., 1 for 45 degrees, 2 for 135 degrees, 3 for 90 degrees and 4 for 0 degree. The structure region is scanned again and the dominant orientation at any point is determined by counting the number of different orientations in a neighborhood. The orientation getting the maximum number of counts is the dominant orientation. As a further refinement, both the dominant direction and its orthogonal direction are used to make a consistency decision. This substantially improves the robustness of dominant orientation determination in the sense of being consistent with the human visual system.
[0069] The consistency decision is made if one of the following conditions is met: (1) The orientation getting maximum counts is greater than a pre-specified percentage (e.g., 0.67) of the total neighborhood counts, and the orthogonal orientation gets the minimum counts. (2) The orientation getting maximum counts is greater than a smaller percentage (e.g., 0.44) of the total neighborhood counts, and the orthogonal orientation gets the minimum count, and the ratio of the dominant count and its orthogonal count is greater than a pre-specified number (e.g., 5). (3) The ratio of dominant orientation count to its orthogonal orientation count is greater than 10.
[0070] Smoothing (3×1) is performed along the direction that gets the most number of counts in that neighborhood. Using a relaxation parameter provided in the algorithm, the dominant orientation smoothing can be minimized while preserving small high-frequency structures.
[0071] The orientation sharpening function (step 132 in FIG. 4) is performed only on orientation-filtered structure pixels that have gradients above a pre-specified limit, e.g., 2(FGT). The specific steps are the following: (1) First, the maximum directional edge strength image is obtained. The one-dimensional Laplacian of the image at every pixel in each of the four directions mentioned above is obtained using the equation: E(k)=2.0*I(k)−I−1)−I(k+1), where the index “k” refers to the current location (i.e., the pixel of interest) along a given direction, E(k) is the edge strength, and I(k) is the intensity value at the pixel. After computing all four edge strengths at a given pixel, the maximum directional edge strength is determined and used in subsequent steps as the edge strength E(x,y) at that location. This process is continued for all pixels in the image. It should be noted that the border pixels in a given image have to be treated differently and are set equal to zero for the subsequent steps.
[0072] (2) The next function is to smooth along the edges of E(x,y). The steps needed for this are the same as before. Each pixel is compared to minimum and maximum threshold values Pixels that exceed the maximum threshold value are set equal to the maximum threshold value. Likewise, pixels which are less than the minimum threshold value are set equal to the minimum threshold value. More specifically, the smoothed edge strength image is referred herein as ES(x,y). If ES(x,y)*Edge>EdgeThreshold, then we set ES(x,y)=EdgeThreshold. Alternatively, if ES(x,y)*Edge<−EdgeThreshold, then we set ES(x,y)=−EdgeThreshold (e.g., Edge=0.3; EdgeThreshold=50).
[0073] (3) The resulting weighted values are added to the initial filtered values for the corresponding structural pixel to form a new filtered image: I(x,y)=I(x,y)+ES(x,y).
[0074] (4) Each pixel is compared to both minimum and maximum threshold values. For example, I(x,y) is set to 0.0 if it is negative and to 4095.0 if it is greater than 4095.0. This upper limit is configurable to any number greater than zero. The effect of these operations is to more strongly enhance weaker edges while providing a more limited enhancement to edges that are already strong.
[0075] In parallel with orientation smoothing of the structure identified within the image, homogenization smoothing of non-structure is performed (step 130 in FIG. 4). The homogenizing smoothing step consists of iteratively low-pass filtering the nonstructure region with a 3×3 kernel. The iterations are done for a set number of times (e.g., iter_number2=10) so that there is no structural information and only the gradual intensity variations remain.
[0076] More specifically, the normalized intensity values for non-structural pixels are considered in this process. The mean neighborhood intensity value for each nonstructural pixel is computed (taking into account the normalized values of structural pixels where these are included in the neighborhood considered). This computation is performed based on a 3×3 neighborhood surrounding each non-structural pixel. This mean value is assigned to the pixel of interest. A determination is then made whether a desired number of iterations has been completed. If not, further homogenization of the non-structural pixel intensity values is carried out. Once the desired number of iterations has been completed, the homogenization smoothing routine is exited. In one embodiment, the operator may set the number of homogenization smoothing iterations from a range of 1 to 10.
[0077] Following orientation sharpening of the structural features of the image and homogenization smoothing of non-structure regions, the entire image is again renormalized (step 134 in FIG. 4). While various methods may be used for this renormalization, in the disclosed embodiment the global average pixel intensity in the filtered image is computed, and a normalization factor is determined based upon the difference between this average value and the average value prior to the filtration steps described above. The new normalized intensity value for each pixel is then determined by multiplying this normalization factor by the filtered pixel intensity, and adding the global minimum intensity value from the original data to the product.
[0078] More specifically, the following operations are performed: (1) compute average pixel intensity (MEAN_AFTER) in the filtered image I filtered (x,y); (2) compute the normalization factor NORM_FACTOR=MEAN_BEFORE/MEAN_AFTER; and (3) compute the normalized image using: I filtered (x,y)=(I filtered (x,y)* NORM_FACTOR)+MIN_ORIGINAL, where MIN_ORIGINAL is the minimum intensity of the original image.
[0079] The resulting renormalized image I renormal is then expanded (step 135 ) by the same factor, interp, by which the input image I raw was shrunk. The structure masks M structure1 and M structure2 are also expanded by the same factor. Various suitable interpolation techniques may be used to accomplish this expansion. The products of the expansion step are expanded structure mask M expanded1 and M expanded2 , and an expanded image I expanded , each with the same dimensions as the original input image I raw . The interpolation method is preferably bicubic for the raw renormalized image to provide a good compromise between computational efficiency and interpolated image quality and bilinear for the binary masks.
[0080] In step 136 , the interpolated, filtered image I expanded (x,y) and the pre-filtration image I raw (x,y) are blended using the equation: I raw (x,y)=α*(I expanded (x,y) I raw (x,y))+I raw (x,y) if M structure1 (x,y)=0, where α is a user-selected parameter Blend such that 0<α<1; else I final (x,y)=β*(I expanded (x,y) I raw (x,y))+I raw (x,y) if M structure1 (x,y)=1, where β is a user-selected parameter edgeBlend such that 0<β<1.
[0081] In addition, noise blending is performed. In step 136 of the algorithm, high frequencies are introduced by adding very small amount of intensity-dependent, uniform random noise to the interpolated image to produce a visually pleasing effect. The amount of noise addition is dependent on whether M structure2 (x,y) is 1 or 0. The preferred amount of added noise is usually less than 5% of the intensity of the filtered pixel.
[0082] The final result I final in then saved for display or any other intended use. The host computer may either output the final image to the display monitor or may enhance the final image before outputting to the display monitor. Such additional enhancement may take the form of non-uniformity equalization followed by contrast enhancement. Although the embodiments have been described with reference to image filtering by a host computer, it will be appreciated by persons skilled in the art that, in the alternative, the enhanced image frame could be generated by dedicated hardware.
[0083] While the invention has been described with reference to preferred embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.
[0084] As used in the claims, the term “computer” means any programmable data processing device or system of intercommunicating programmable data processing devices capable of performing computations in accordance with a program. In particular, the term “computer” includes, but is not limited to, dedicated processors and general-purpose computers. | In ultrasound imaging, acquired images are corrupted by slowly varying multiplicative non-uniformity. When the image is corrected for non-uniformity alone, noise in the dark regions of the original image becomes multiplicatively enhanced, thereby providing an unnatural look to the image. A pre-filtering technique is used to reduce noise in ultrasound pixel images by shrinking initial image data and processing the shrunken image with known segmentation-based filtering techniques that identify and differentially process structures within the image. The segmentation is based on both gradient threshold and the distance from the near field of the ultrasound image. This modification selectively suppresses near-field artifacts. After processing, the shrunken image is enlarged to the dimensions of the initial data and then blended with the initial image to form the final image. During blending, a small predetermined fraction of intensity-dependent, uniform random noise is added to the non-structure region pixels whose intensities are above a pre-specified intensity threshold, to mitigate ultrasound speckles while leaving non-echogenic regions undisturbed. | 6 |
CROSS REFERENCE TO RELATED APPLICATIONS
The present application is related to the patent application of Zdybel et al. entitled "Hardcopy Lossless Data Storage and Communications For Electronic Document Processing Systems," filed on or about the same date as the filing of the present application, and incorporated by reference herein.
BACKGROUND OF THE INVENTION
The present invention relates generally to document processing, and more specifically to documents having printed thereon indicia of the position, size, type, and the like, of fields which may contain data to be extracted from the document, and systems for producing and utilizing same.
Machine readable forms have been in common use for some time. Such forms provide a mechanism for enabling actions to be taken based on marks on a paper without requiring human intervention such as reading or interpreting the forms. The marks on such forms are extracted under the control of a device commonly referred to as a form interpreter. The forms are "read," most often optically by a scanner or the like, and the form interpreter then locates and characterizes the marks on the forms, and may output control signals as a function of the presence, location, nature, etc., of the marks to peripheral devices.
A "form" of the type discussed above is defined for the purposes of the present invention as either a tangible printed document or the like or a data structure representing such a tangible printed document. The form may contain regions of arbitrary text, arbitrary graphics, and fields. "Fields," as used herein, is taken to mean regions of the form, either physical regions of the printed document or structured regions of the data structure representing the printed document, which are to be modified by a user. As used herein, a "user" may be either human or machine. Further, as used herein "modify" shall be taken to mean enter, add, delete, change, alter, connect, disconnect, highlight, fill-in, erase, strike-out or the like, when referring to a field. Examples of fields include "check box" fields (also called "bubbles"), alpha or alpha-numeric fields, image fields, etc. A form will often also include a reference point indication from which the location of the fields may be measured.
Information carried by forms can conveniently be divided into three categories: data, machine instructions, and other information. As used above, data is taken to mean information carried by the form to be read or extracted from the form for processing. Examples of data include blank or filled-in bubbles on a standardized examination answer form, payee fields on checks which are parsed for processing, etc. Machine instruction as used above refers to information carried by a form which is interpreted by the forms interpreter and which causes action either by the forms interpreter or by a remote device. Examples of machine instructions include information located on a form which, when read, cause data to be copied to or from memory locations of a computer, cause a mathematical or logical procedure to be applied to particular data, etc. Other information, as used above, refers generally to information ignored by the form interpreter, such as the arbitrary text and graphics mentioned above, prompts or instructions on the form to aid the user in filling in fields, information for the user's interest, ornamental treatment, etc. The first two categories of information, data and machine instructions, are of interest herein.
Forms carrying data are the most common type of form, and examples may be readily found in the art. For example, U.S. Pat. Ser. No. 4,634,148, to Greene, issued Jan. 6, 1987, teaches a form which is a draft check carrying data in the form of payee, amount, and maker. The fields carrying the data are located and the data is extracted for processing according to a preprogrammed scheme. Forms carrying instructions interpreted and used by machines are also known, for example for Rourke et al., U.S. Pat. No. 4,757,348, issued July 12, 1988. Rourke et al. discloses an electronic reprographics/printing system which uses printed control forms, called separators, to segregate groups of documents from one another and to input control or programming instructions for processing the documents associated with each control form. In fact, forms carrying data as well as machine instructions are known, for example as taught by Tanaka in U.S. Pat. No. 4,494,862, issued Jan. 22, 1985. Tanaka describes a system wherein a form is given a bar code which, when interpreted by the forms interpreter section of the system, causes the system to read and print only those rows on the form marked with a special pen (see, e.g., col 8, lines 32 et seq.)
Another reference of interest is the patent to Daniele, U.S. Pat. No. 4,728,984, issued Mar. 1, 1988. This reference relates to a system including an electronic printer for recording digital data on plain paper, together with the use of an input scanner for scanning digital data that has been recorded on such a recording medium to upload data into an appropriate device such as a computer or the printer itself. The applications of the system of this reference, however, are limited to decoding secret documents and inputting program information into a computer.
Forms of the data carrying type may in fact carry several different types of user applied data. For example, the above mentioned bubbles on a standardized examination answer form and the payee fields on checks which are parsed for processing represent two different types of data. In general, the data types are: digitally coded data, for example the filled-in or not filled-in state of a bubble; data for character recognition, such as bar codes, alpha-numerical data for optical character recognition (OCR) and the like; and data for image-wise handling, such as the payee field mentioned above, graphics and the like.
It is important for a practical form-using system to be able to distinguish between the various data types. One method for doing so is disclosed by Greene in U.S. Ser. No. 4,558,211, issued May 13, 1986. This reference discloses a machine readable document having fields identified by a coating of fluorescent ink. Data is written into the fields by the user on top of the fluorescent ink such that when the fields are illuminated by a proper light source, the written data will be black in sharp contrast to the fields. The fields include a binary coding which is applied by selectively blanking out regions of the fluorescent ink at the border of the fields, or regions of fluorescent ink remote from but logically associated with the field, for example as shown in FIG. 5, and discussed at col. 7, line 14, through col. 8, line 6. Greene distinguishes between the various data types by using the coding to cause different fields to be copied to different locations for printing.
Although machine processing of forms results in high speed and accuracy of processing, the systems disclosed in the previously mentioned references have several important limitations. These limitations have, inter alia, forced the use of machine read forms to be practical only when large numbers of identical forms are used, limited the organization and aesthetics of forms, and complicated the form creation process.
First, the form interpreter must be preprogrammed with a description of the form in order to locate the form fields. In most cases, a description of the physical location of the fields or parts of the fields relative to a reference point must be preprogrammed. This preprogramming requires substantial time, effort, and training, and most often is performed by an operator different from the person making up the form itself. Generically, there is a presently infilled need in the art for a form, electronic or paper, which may be interpreted by a general form parser that has no previous knowledge of the form.
A second limitation is that any encoded instructions relative to specific data must either by physically part of the data field or otherwise physically or logically associated with the data field. It is desirable for form organization and aesthetics to be able to locate instructions (as well as other relevant information about form content and structure) at any arbitrary position a form designer chooses.
A third limitation is that a form designer has had to separately create fields then add supplemental information, such as coded field type, if coded information about the fields is to be carried by the form. It is desirable to allow simultaneous creation of a form and creation of a coded description of the form. That is, a form creation system is needed that allows a form designer to create a form such that the system keeps track of the position, type, etc. of fields of the form, and automatically includes the coded description in the form's data structure and/or automatically prints the coded information on a printed copy of the form together with the alphanumerics, graphics and other elements of the form.
A fourth limitation is that present form interpreters require manual reprogramming prior to form interpretation. However, a form interpreter system is desired which works with coded forms to read from the form instructions on extraction and handling of the data and other information the form carries.
Related to this limitation is another limitation--it has heretofore not been possible to remotely program a form interpreter. That is, presently, to program a form interpreter the programmer must have direct physical access to the workstation, personal computer, or the like, which controls the interpreter. A method and apparatus is desired for programming the interpreter remotely, say via a paper form, transmitted to the interpreter by facsimile, via communication directly from the work station or personal computer the form resides on, etc.
Yet another limitation is that the above described art is not capable of designating a field as more than one data type. That is, it has hereto fore not been possible to designate the contents of a field for a variety of different processing. The ability to so designate the contents of a field for multiple processing avoids the need for rescanning, saving both processing time and computer memory space.
The realization and overcoming of the above limitations, and others not mentioned herein, form aspects of the present invention, which is summarized and described by way of illustrative embodiments below.
SUMMARY OF THE INVENTION
The present invention encompasses a novel form and systems for creating and interpreting such a form. The form itself, whether represented electronically or printed in hard copy, carries an encoded description of itself. The form may include one or more of a variety of types of fields, as well as other non-field information. The form generation portion of the system automatically encodes information about the fields as the form is being created, and integrates that encoded information into the electronic and printed representations of the form. The forms interpreter portion of the system may then read the form's field description from the form itself and, based on this description, interpret the form. By locating encoded information about form fields directly on the form, the form interpreter may be quickly, simply and automatically programmed for that particular form. Thus, it becomes practical to use specialized forms. The programming of the interpreter by the encoded form information may be by scanner or, remotely, by facsimile. The system also is capable of allowing direct station to station communication of the forms via facsimile or network communication protocols. Furthermore, the resulting forms, when in hard copy format, may be reproduced using standard office duplicating equipment.
The system includes:
A forms description language;
A computer based editor for creating and printing forms;
Computer software to convert a facsimile input into an image file; and
Computer software to process the image file, either from facsimile or from a scanner, so as to retrieve the form's description and interpret the form.
The form may be structured in virtually any manner, and include arbitrary text, arbitrary graphics, and a variety of fields such as check boxes, alpha-numeric, and/or image fields among others. In addition, the form will include encoded information. In the hard copy representation of the form, this encoded information may be printed on the face of the form. In the electronic representation of the form, the encoded information will be part of the data structure of the form. The encoded information will either be in a predefined location so that the interpreter may be programmed to look for it in that location, or the form may be searched for its location. In either case, the form will also include a reference point from which the form's layout is calculated.
The nature of the particular coding scheme is not important to the present invention, other than that whatever scheme is used, it must be able to encode the information compactly enough that room is not displaced which is needed for the fields themselves. Examples of acceptable coding schemes include barcodes, morphological glyphs, etc.
The system is composed of several components including a computer-based form design tool and interpreter. The form design tool allows the user to choose or create a variety of fields such as check boxes, alpha-numeric or graphic fields, etc. When the user creates a form, the design tool automatically creates a description of the form. When the user selects and locates a field on the form, the form design tool incorporates a description of the field, including the type or types of field and its location, into the form description. When the form is printed, an encoded description is automatically printed on the form. The user may supplement the type and location information with other information, such as an operation to be performed on the contents of a field, specific interrelationships between contents of two or more fields, other action to be taken, etc. This supplemental information also becomes part of the form description which is encoded by the design tool.
The interpreter will typically be embedded in software. It will accept information from a scanner and be capable of culling from the scanner information the encoded information representing the form description. The interpreter will interpret the encoded information and perform either preprogrammed operations on the information located in specified fields or of a specified data type, or perform operations on that information from instructions encoded with the form description itself.
Distinguishing between the various data types and machine instructions by indications carried by the form itself are of particular interest herein. A form virtually complete unto itself (i.e., carrying data and instructions relating to that data) conserves valuable memory space on computers used in a form handling system, reduces programming of the form interpreter, allows one form to be read on a variety of different machines or by a variety of different form handling systems, etc. Thus, the present invention provides a complete and convenient form processing system, overcoming the limitations of the prior art.
The scope of the present invention and the manner in which it addresses the problems associated with prior art methods will become more readily apparent from the following detailed description when taken in conjunction with the accompanying drawings and claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows one embodiment of a printed form according to the present invention;
FIG. 2 shows one embodiment of a data structure representing a form according to the present invention;
FIG. 3 is a flow chart of one embodiment of a system for the processing of a form carrying a coded description of the location, type, etc., of user modifiable fields according to the present invention;
FIG. 4 shows one embodiment of a system for generation of a form carrying a coded description of the location, type, etc., of user modifiable fields according to the present invention; and
FIG. 5 is flow chart representation of a process for creating a form carrying a coded description of the location, type, etc., of user modifiable fields according to the present invention.
DETAILED DESCRIPTION
Turning now to FIG. 1, one aspect of the present invention, a blank form 10 according to one embodiment of the present invention, is shown. The format of the illustrative form is a printed paper document, the paper itself being a common example of generic "carrier means," on which there may be imparted marking or "indicia" of various types. Form 10 is of the type on which a user may impart markings, which markings may be read or sensed by a machine such as an optical scanner. The markings imparted by the suer represent data, often of the type to be stored in a digital computer memory or the like. The markings imparted by the user need to be located at specific locations on the form so that the form interpreter may be instructed where to look for the data to be read. Thus, some aid needs to be provided to the user to facilitate proper location of the markings. To this end, form 10 will generally include printing prior to use, such as an outline of field regions to be filled in, borders of image fields, etc. To further assist a user in completing a form, printed instructions are often preprinted on the form itself.
The preprinting on form 10 may include arbitrary text 12, such as document or field titles, the above mentioned instructions and the like, and arbitrary graphics 14 such as graphical symbols, the above mentioned field outlines, etc. The length, size, position, content, and other details of the arbitrary text 12 and arbitrary graphics 14 do not impact the nature of the present invention. In fact, a form interpreter utilizing a form such as that described herein will ignore the arbitrary text 12 and arbitrary graphics 14 in favor of the contents of certain fields and encoded information regions.
In order to facilitate locating regions of form 10 marked for reading, i.e., fields, form 10 includes a reference point 16 from which the layout of the remainder of the form is calculated. The form interpreter locates this point, and measures position of the contents of the fields to be read therefrom. A convenient location for reference point 16 is the upper lefthand corner of the form. Thus, the location of any field may be described in terms of horizontal and vertical displacements from the reference point.
A form according to the present invention will include one or more arbitrarily located field regions, which include one or more fields of the type described above. These fields may be "check boxes" (or "bubbles") as indicated by reference numeral 18, single or multi digited numeric or alphanumeric fields, such as the multi digited numeric field 20, and/or the multi character alpha field 22. Image fields 24, i.e., regions of text, graphics or other information scanned and saved as a single image, are yet another type of field which may be located on document 10. Arbitrary graphics 14 should be distinguished from the contents, if any, of image field 24. Whereas the contents of field 24 will be maintained as data for processing, a form interpreter utilizing a form such as that described herein will ignore the arbitrary graphics 14, much as it will ignore the arbitrary text 12.
A region of encoded information 26 which represents a structural description of form 10, as well as other selected information, will be located on the form itself. The encoded information contained in region 26 includes, inter alia, the complete description of the location of the fields on the form which enables arbitrary placement of the fields on the form. In fact, region 26 may also be arbitrarily located. Specifically, region 26 need not by physically or logically placed on form 10 with reference to the fields. Rather, in one embodiment, the form interpreter is instructed where on form 10 region 26 may be found. Alternatively, the form may be searched for region 26, based on data type, format, etc. Once located, the information contained in region 26 may be read by a scanner and decoded by appropriate decoding means to provide the position information needed to read and process the remainder of the form. It is important to note that by providing a complete description of the location of the field on the form itself the fields may be arbitrarily located on the form. That is, the fields may be located at any position on the form convenient or desired.
The method of coding the information contained in region 26 may be by any convenient machine readable coding scheme. One example is the so called "bar codes" well known in the art. Another well suited scheme is described in U.S. Patent application entitled "Self-Clocking Embedded Digital Data," by Bloomberg, et al. This particular coding scheme allows a sizable amount of information to be encoded and carried by the form in an aesthetically pleasing format.
The encoded information carried by region 26 may include a description of any attribute of the form as described in the aforementioned copending patent application of Zdybel et al. ("Hardcopy Lossless Data Storage . . . "). However, at a minimum, the encoded information will include a description of the physical location of one or more fields on form 10, relative to reference point 16, and a description of the type of that one or more fields (i.e., bubble, alpha-numeric, image, etc.) Examples of the further types of information which may be carried by region 26 are instructions to a processor for specific processing of selected data, including data remote of form 10, dialing instructions to a facsimile machine acting as an interface between the document scanner and the form interpreter, network addresses for the routing of selected data, data itself which is to be processed, etc. The point here is that by providing a region of encoded information which ties directly to user modifiable fields, a form may be provided that is a direct path between user and form interpreter--no preprogramming of the form interpreter is required. Furthermore, programming of processing apparatus may also be accomplished by the encoded information, thus alleviating the need to preprogram that portion of a data processing system as well.
The above form description has been given with respect to a single page form. It will be appreciated that the foregoing description applies equally to single forms of more than one page. That is, each page of a multi page form should include a reference point, such as point 16, at least one field, such as fields 18, 20, 22, or 24 and a region of encoded information, such as region 26. However, it will also be appreciated that by proper coding of information in region 26, a form interpreter may be programmed to recognize pages of a form carrying less than all of the above. For example, a form interpreter may be programmed by reading the coded information of region 26 (by methods such as the one described further below) to skip one or more pages of a multi page form which do not contain fields. Likewise, the locations of fields on various pages could be programmed via a single encoded information region so that each page need not carry such a region.
The description above of the form aspect of the present invention has been from the point of view of a paper document. It will be appreciated, however, that the nature of the present invention lends itself equally well to an entirely electronic form, of the type that may be transferred from one portion of a data processing system to another, or from one data processing system to another. For example, an electronic form 30 may be a structure of digital data of the type shown in FIG. 2, including control information region 32, predefined data region 34, user modifiable (field) data region 36 and form processing and description region 38. Again, the form will have associated with it one or more fields and encoded information allowing a direct path between user and form interpreter. Here, however, the encoded information will be an indication of the location of field data in the data structure (i.e., pointer location or the like).
Another aspect of the present invention is the processing of data by way of a form of the type described above. By way of example, a system for the processing of a form carrying a coded description of the location, type, etc., of user modifiable fields is shown in FIG. 3. According to the embodiment of the invention illustrated, the system comprises a scanner 50 of the type capable of converting the appearance or image of a form, such as form 10 of FIG. 1, into an electronic representation such as a bitmap or the like. The electronic representation of the form is passed from scanner 50 to a recognition unit 52 which includes recognition software for converting the bitmap or similar representation into elemental textual and graphical data blocks to the extent possible. For example, state-of-the-art recognition software generally can correlate printed typographic characters with their ASCII encodings with substantial success. Additionally, the recognition software is sometimes capable of inferring some or all of the page layout features of the form from its bitmap representation, thereby allowing identification of particular regions of information based on physical location, and capable of making probability-based determinations of character type or font of printed text, thereby allowing identification of particular regions of information based on character type. The aim at first pass through the form is to locate the region(s) of encoded information and to decode the information to allow further processing of the form. This may be done in one of at least two different ways. First, the encoded information region will be located form the location of a reference point and preprogrammed information about the location of the encoded region relative to the reference point. According to this method, recognition unit 52 will locate the reference point, such as reference point 16 on form 10, FIG. 1. Recognition unit 52 will then pass the reference point location information to preprocessing unit 54, which will cause displacement information to be called from memory device 56, such as a ROM unit, and add that displacement information to the reference point location information to obtain the beginning point of the encoded information region. The second method of locating the encoded information region assumes that recognition unit 52 is capable of uniquely identifying the characters or symbols comprising the encoded information region. In essence, recognition unit 52 scans the electronic representation of the form for a predefined data type, i.e., the specific symbols used for encoding. When the first of these glyphs are encountered, it may then be known that the encoded information region has been located.
Once located, the encoded information must then be decoded. This is the role of decoding unit 58. The input to decoding unit 58 will be the electronic representation of information encoded by one of the above mentioned encoding schemes. By way of example only, such information may include the location and type of a field, and a destination in computer memory at which to store the data contained in the field. The output of decoding unit 58 will be input to processing unit 60. The decoded information is then utilized by processing unit 60 to determine the physical location of the field, and to perform the designated operation upon the contents of the field, i.e., copy the contents into the specified memory location. It will be appreciated at this point that virtually any processing of the data contained in the field may be performed by processing unit 60. Several different operations may be performed on a single field's contents, and a single operation may be performed on the contents of several fields. Furthermore, there is no practical upper limit on the number of fields that may be processed in the manner described above. Thus, although not shown in FIG. 3, processing unit 60 will generally be in communication with peripheral units such as memory units, display units, printing units, etc., for peripheral processing of selected data.
As previously mentioned, the present invention contemplates processing forms entirely in their electronic representation. In such cases, there will be no printed copy of the form, and thus no need for scanner 50 in a system for processing such a form. Rather, if the electronic representation of the form is compatible with the capabilities of recognition unit 52, the electronic representation may be directly passed to recognition unit 52, and processing of the form is as described above. If, however, the electronic representation of the form is in a format incompatible with the capabilities of recognition unit 52, a translation or conversion unit (not shown) may be interposed between the form source and recognition unit 52, as will be readily appreciated by one skilled in the art.
Yet another aspect of the present invention is a system for the generation of a form which includes user modifiable fields and an encoded information region carrying information about the processing of the form. By way of example, FIG. 4 details such a system 70. According to this aspect of the present invention, a form of the type described above may be created on a device such as a personal computer (P.C.) or work station 72 having a form creation package resident thereon or accessible thereto. The P.C. or work station will generally be in communication with one or more peripheral devices such as a printer 74, a facsimile machine 76 or another P.C. or work station 78.
The system and steps utilized by the P.C. or work station 72 for creation of a form is detailed in FIG. 5. On a display presenting an image of the form, a user will select or create one or more fields, by way of a field source means, to be carried by the form at step 80. The field source means may be a field library, user interface device such as a keyboard, or other system input such as a scanner or the like. After selection or creation, a field is positionally located on the form at step 82, and information about selected attributes of the field, such as type, size, location, etc., is stored in a form memory at step 84. Similarly, a user may select of create and locate arbitrary text and graphics at steps 86, and 88 respectively.
As a field is selected or created, the user may wish to specify an operation or operations to be performed on later added contents of the field at 90. Operations and/or data independent of the contents of any field may also be entered at this point. Such an operation may be symbolically entered (e.g., c=a+b, a mathematical relationship where the contents of fields a and b are added and the result put in memory location c) or logically entered (e.g., if field x is filled-in, move the contents of field y to the memory location z). Data may be directly entered (e.g., move the value "5" into memory location 1). The operations and/or data may be selected from an operation library, or input on a user interface device such as a keyboard. Such operation and/or data will also be stored in the form memory at 84.
It may be desirable when displaying the fields, text, graphics, etc., not to include a display of the operations and/or data. Assuming that the operations and/or data are not to be displayed, the display function 92 may be interposed between the locate functions 82 and 88, and the form description memory function 84. The display function may, of course, be located elsewhere in the system for the purposes of displaying more or less information than fields, text, and graphics.
Virtually simultaneously with the creation of the form itself, an encoded form description is created. The encoded form description may or may not include the arbitrary text and graphics, as described above. Assuming for illustration purposes that the arbitrary text and graphics are not to be encoded, the step of encoding the relevant information is shown at step 94, interposed between the locate and select function 82 and 90, and the store in form memory function 84. The encoded information is next stored in an encoded description memory at step 96. Of course, the encoding of step 94 and storage of step 96 may be located elsewhere in the system for the purposes of encoding and storing more or less information than fields and operations. Furthermore, the makeup of the encoding apparatus used is a function of the scheme used to encode the information. In the schemes described above a look-up table is generally the interface between the uncoded and coded data. However, the details of the coding apparatus and scheme are beyond the scope of the present invention. The key point is that selected information is passed to a description encoder which creates an encoded version of the information, nearly, if not in parallel with the creation of the form itself.
For the purposes of printing the form or transmitting the form electronically for use, the form and its encoded description must be merged. This is done at step 98 by a form composer. The form composer will be preprogrammed with certain instructions about the placement of the text, graphics, fields and encoded information. For the purposes of a printed form, it is the role of the form composer to ensure that all of the relevant information is fit onto the printed page. For the electronic version of the form, it is the role of the form interpreter to properly located the various components of the form in the appropriate data structure. Once composed, the form may be output at 100. The form may be printed, sent via facsimile, sent via electronic network to P.C.s or workstations, etc., for copying, printing, editing or use.
In the case of a machine acting in the role of user, the machine would generate a form with encoded description in response to a request, instruction or the like in a manner similar to that described above. For example, a request may be made via computer of facsimile for information on a particular subject, eliciting a response in the form of a printed paper form with bubbles to be filled in representing available specific items on the particular subject which may be requested. The machine may assemble a form from a library of field types, following predefined layout instructions, while maintaining a description of the form to be ultimately encoded and printed on the form or made a part of its electronic description. Again, the resulting form may be hard-copy or an electronic representation of the form.
In general, to those skilled in the art to which this invention relates, many changes in construction and widely differing embodiments and applications of the present invention will suggest themselves without departing from its spirit and scope. For example, the above description has focussed on forms carrying encoded information representing the location, type, processing, etc., of the fields associated with a form. It is within the scope of the present invention, however, that a complete description of all of the contents of a form, including arbitrary text and arbitrary graphics be encoded enabling a complete re-editing as appropriate.
Also, the above description has been from the point of view of a form carrying its own encoded description for the purposes of processing. It will be appreciated, however, that a stand-alone encoded description could be used for the programming of a form interpreter to handle one or more forms to be interpreted. In addition, the encoded data could be or include an identifier which identifies the form so that the form interpreter may rely on a previously programmed description of the form.
Furthermore, use of individual aspects of the present invention, such as the form itself, have been described only by way of example, and such description is not intended to be in any sense limiting. For example, although a form may be used by directly marking the form with, say a pencil, then scanning the form to extract the imparted data, a form according to the present invention may also be used by displaying the form on a P.C., work station or the like and entering the data by means of an appropriate input device such as a keyboard, mouse, etc.
In summary, it will be appreciated that the present invention provides a simple and convenient way to access or store data, or program a form interpreter for the processing of data contained on a form. The present invention makes practicable the use of customized forms of forms used in small numbers, reduces the burden of programming the form interpreter, and reduces the required memory space associated with a form interpreter, among other benefits, by creating a direct correlation between an encoded description and processing of the form and the data the form carries. | A form including user modifiable fields and an encoded description of the location, size, type, etc. of the fields allows direct programming of a form interpreter. Other information including the processing of the form, encoded data, etc., may be included in the encoded information. A system for creating forms carrying an encoded description of selected attributes of the fields includes means for selecting or creating fields and locating the fields on a form while generating, substantially simultaneously, the encoded description of the selected attributes. A form composer then allows merging of the form and its encoded description for printing or electronic transmission. A system for reading such forms includes a scanner, decoding device, and processor. By reading such forms, data may be entered into or recalled from a data processing system, or a form interpreter may be programmed, locally or remotely, for subsequent handling of forms. | 6 |
This is a continuation of application Ser. No. 646,484, filed Aug. 31, 1984, now abandoned, which in turn is a continuation of Ser. No. 532,521 filed Sept. 12, 1983, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to district heating pipes for potable water which contain a polymeric composition which has particular utility for hot water pipe service. In particular, the present invention relates to a polymeric composition comprising a butene-1 homopolymer and a particular group of additive components.
2. Description of the Prior Art
Since its introduction in the United States in the early 1970's, the major market for butene-1 polymers has been in hot water extruded pipe applications. For the most part, these prior art butene-1 polymer compositions comprised a butene-1 polymer along with various standard antioxidants. In these plumbing applications, the flexibility of the butene-1 polymers, its good creep resistance over a wide range of temperatures and high hydrostatic design stress rating were very useful properties. However, one drawback of the prior art polybutylene plumbing resins is the deactivation of stabilizer due to hot water aging, leading to partial loss of stability. Especially for more demanding applications such as district heating where the pipes are continuously exposed to hot water, improvements were required in the prior art plumbing grade resins. The present invention deals with a combination of ingredients in a butene-1 polymer composition that is a significant improvement in the art.
SUMMARY OF THE INVENTION
The present invention relates to district heating pipes for potable water which contain a butene-1 homopolymer composition having particular utility in hot water pipe service. In particular, the present invention comprises a polymeric composition consisting essentially of an intimate blend of:
(a) about 93 to about 98 percent by weight of an isotactic butene-1 homopolymer;
(b) about 0.05 to about 0.5 percent by weight of bis-[3,3-bis(4'-hydroxy-3'tert.butyl-phenyl)-butanoic acid]-glycolester;
(c) about 0.2 to about 0.7 percent by weight of lauryl-stearyl thiodipropionate;
(d) about 0.02 to about 0.6 percent by weight of a nucleating agent;
(e) about 0.5 to about 3.0 percent by weight of filler component comprising a mineral filler coated with an acid acceptor; and
(f) zero to about 3.0 percent by weight pigment.
While each of the ingredients (a) through (e) are significant in achieving the overall balance of excellent properties, it is important to note that the invention is directed to a combination of ingredients. This combination of ingredients could not have been synthesized by just picking and choosing, for example, the best antioxidant and the best nucleant, etc. A significant aspect of the present invention is how the various ingredients work together, therein resulting in a superior product. The butene-1 homopolymer, of course, is important in providing good creep resistance over a wide range of temperatures and high hydrostatic design stress rating which is based on high hoop stress. The sterically hindered phenolic antioxidant provides oxidative stability. The lauryl-stearyl thiodipropionate is a costabilizer and acts as a hydroperoxide decomposer. It has been found here that in combination with the particular antioxidant claimed, a significant effect on long term stability is obtained. The nucleating agent results in faster pipe extrusion speed and an overall improvement in pipe properties. Further, the presence of a high density polyethylene nucleant in the formulation results in higher elongation and break strength in the machine direction.
The resulting overall polymeric composition has an excellent, superior balance of properties not available in prior art formulations. Of most significance, the formulations of the present invention possess an estimated long term stability in hot water (95° C.) service which is considerably improved over that for prior art formulations.
DETAILED DESCRIPTION OF THE INVENTION
The butene-1 homopolymer employed herein is an isotactic butene-1 homopolymer. The polymers used herein are suitably crystallizable thermoplastic butene-1 polymers with number average molecular weights over 15,000, preferably above 20,000 and an isotactic content above 85%, preferably above 90%, and more preferably above 95%, determined as the diethyl ether-insoluble component. Suitable isotactic butene-1 polymers are commercially available and methods for their preparation are well known in the art, as shown in, for example, U.S. Pat. No. 3,362,940. Illustrative of butene-1 polymers suitable for use in the present invention (if the above requirements are met) are those known in the industry as pipe grades. Especially preferred are Shell butene-1 homopolymer.
The antioxidant employed herein is a sterically hindered phenolic antioxidant. Preferred antioxidants are HOSTANOX® 03, available from American Hoechst Corp. and Cyanox® 1790, available from American Cyanamid Corp.
HOSTANOX® 03 is bis-[3,3-bis(4'hydroxy-3'tert.butyl-phenyl)-butanoic acid]-glycolester and has the structure: ##STR1##
Cyanox® 1790 is 1,3,5-Tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione.
Lauryl-stearyl thiodipropionate has the structure ##STR2##
Another necessary component of the present invention is a nucleating agent. Nucleating agents contemplated in this invention include by way of example:
high density polyethylene;
graphitic non-turbostratic carbon;
fatty acid amides;
anthraquinones;
and amides.
Other nucleating agents are also contemplated for use in this invention. Graphitic non-turbostatic carbon nucleating agents are disclosed in copending application Ser. No. 183,869 filed 9/4/81, now U.S. Pat. No. 4,321,334 (having common assignee). Fatty acid amide nucleating agents are disclosed in copending application Ser. No. 216,055 filed 12/15/80, now U.S. Pat. No. 4,322,503 (having common assignee). These fatty acid amides include specifically N,N'-ethylene-bis-stearamide and stearamide. Anthraquinone nucleating agents are disclosed in copending patent application Ser. No. 218,865 filed 12/22/80, now abandoned (having common assignee). Specific anthraquinones include 1,2-dihydroxy-9,10-anthraquinone; 1,4-dihydroxy-9,10-anthraquinone; 1,5-dihydroxy-9,10-anthraquinone; 12,5,8-tetrahydroxy-9,10-anthraquinone; 9,10-anthraquinone; and sodium 2-anthraquinone sulfonate. Amide nucleating agents are disclosed in copending application Ser. No. 214,148 filed 12/8/80, now abandoned (having common assignee). Preferred amides include 1-naphthalene acetamide; N-stearoyl-p-aminophenol; mercapto-N-2-naphthylacetamide; malonamide; nicotinamide; isonicotinamide; benzamide; phthalimide; salicylamide; anthranilamide; and 1,8-naphthalimide.
A much preferred nucleating agent is high density polyethylene. The high density polyethylene employed in the composition of this invention is characterized by a density above about 0.93 g/cc and preferably at least about 0.95 g/cc. An HDPE with a melt index of from about 0.1 to 20, as measured by ASTM D1238, Condition E, is typically employed; HDPE of higher melt index may also be suitable. The melt index and molecular weight of HDPE are inversely related; the corresponding molecular weight for a polymer with a given melt index may be readily determined by routine experimentation. A particularly suitable HDPE, for example has a melt index of 0.45 g/10 min., a weight average molecular weight of about 166,000 and a density of 0.950 grams/cm 3 . A high density polyethylene with a viscosity at mixing temperatures approximating that of the butene-1-homopolymer facilitates intimate mixing in conventional extrusion compounding equipment. A wide variety of suitable high density polyethylenes are commercially available and methods for their preparation are well known in the art. They may be prepared by polymerization processes employing Ziegler type coordination catalysts or supported chromium oxide catalysts. Commercially available HDPE of either type is suitable. "HDPE" refers to high density polyethylene of the type described. As shown in the examples, the HDPE significantly increases the pipe extrusion speed. Also, as shown in the Illustrative Embodiments, the HDPE unexpectedly increases the elongation (MD) of the composition.
The filler component employed in this invention is a coated mineral filler, in particular a magnesium silicate coated with an acid acceptor. The preferred magnesium silicate is talc which is described in Kirk-Othmer, "Encyclopedia of Chemical Technology", Second Edition, Volume 19, pages608 et seq. The acid acceptors which are coated on the mineral filler are preferably stearates of weak bases, such as alkaline earth metal stearates. A preferred acid acceptor is zinc stearate. Accordingly, the preferred filler component is zinc stearate-coated talc. Such materials are well known, commercially available fillers.
In addition to adding certain strength properties to the composition of the invention, the particular fillers employed herein also unexpectedly improve the long term stability of the blends.
Pigments are added as desired to achieve a particular color for the resin. Typical pigments include carbon blacks, titanium dioxide, and iron oxide.
The relative amounts of each of the various ingredients in the polymeric composition of the present invention, are listed below in percent by weight (the total for a particular composition adding up, of course, to 100 percent):
______________________________________ Preferred More Preferred______________________________________Butene-1 homopolymer 93 to 98 95 to 97Antioxidant 0.05 to 0.5 0.1 to 0.3Costabilizer 0.2 to 0.7 0.3 to 0.5Nucleating Agent 0.02 to 0.6 0.025 to 0.5Filler 0.5 to 3.0 1.0 to 2.0Pigment 0 to 3.0 1.0 to 2.0______________________________________
The relative amounts of these various ingredients are important in achieving the overall balance of superior properties. For example, it has been shown that if too much stabilizer is added some of the stabilizer will bloom to the surface. If desired, various other ingredients such as conventional fillers, thermal and ultraviolet stabilizers, processing agents, tracer compounds and/or other additives may be incorporated into the polymer composition so long as their addition does not significantly effect the properties of the present composition. In this event, it is understood that these other materials are excluded when calculating the added concentration of the various ingredients of this invention.
In a preferred embodiment, the various ingredients are blended or intimately mixed in an intensive mixing device such as a twin-screw extruder or Banbury mixer. The resulting blends have particular utility as extruded pipe for hot water service in view of the long-term stability of such resins in hot water.
The invention is further illustrated by reference to the following Illustrative Embodiments, which are given for the purpose of illustration only and are not meant to limit the invention to the particular reactants and conditions employed therein.
ILLUSTRATIVE EMBODIMENT I
In Illustrative Embodiment I, twelve different formulations were examined. The various ingredients employed in the five formulations were:
__________________________________________________________________________Ingredient Trade Name Description__________________________________________________________________________butene-1 homopolymer Shell polybutylene Pipe grade, butene-1 homo- polymer with melt index of 0.4 dg/min and number average molecular weight of 73,000hindered phenolic HOSTANOX ® 03 See earlier descriptionantioxidanthindered phenolic IRGANOX ® 1010 (3',5'-di-tert-butyl-4'-antioxidant hydroxyphenyl) propionate methane or tetrakis (methy- lene (3,5-di-tert-butyl-4- hydroxyhydrocinnamate) methanehindered phenolic CYANOX ® 1790 1,3,5-Tris(4-tert-butyl-3-antioxidant hydroxy-2,6-dimethylbenzyl)- 1,3,5-triazine-2,4,6-(1H,3H, 5H)--trionehindered phenolic NAUGARD ® XL-1 2,2'-oxamidobis-[ethyl 3-(3.5-antioxidant di-tert-butyl-4-hydroxyphenyl) propionate]Costabilizer CYANOX ® 1212 lauryl-stearyl thiodipropionateCostabilizer SEENOX ® 412S Pentaerythritol tetrakis (β-lauryl thiopropionate)Costabilizer HOSTANOX SE-10 Dioctadecyl disulphideHDPE DuPont 7815 High density polyethyleneFiller Component Mistron ZSC Zinc stearate-coated talc__________________________________________________________________________
Other ingredients employed in the formulations were standard carbon blacks, TiO 2 and tracer compounds.
The various ingredients were prepared by first masterbatching the ingredients in a Banbury mixer. Then the masterbatch was let down with the remaining butene homopolymer in an extruder at about 200° C. The formulations are presented below in Table 1 (relative amounts are expressed in weight percent):
TABLE I__________________________________________________________________________ Formulation No.Ingredient 1 2 3 4 5 6 7 8 9 10 11 12__________________________________________________________________________Cyanox 1790 0.2 -- -- -- 0.2 -- -- -- 0.2 -- -- --Hostanox 03 -- 0.2 -- -- -- 0.2 -- -- -- 0.2 -- --Irganox 1010 -- -- 0.2 -- -- -- 0.2 -- -- -- 0.2 --Naugard XL-1 -- -- -- 0.2 -- -- -- 0.2 -- -- -- 0.2Cyanox 1212 0.4 0.4 0.4 0.4 -- -- -- -- -- -- -- --Seenox 412S -- -- -- -- 0.4 0.4 0.4 0.4 -- -- -- --Hostanox SE-10 -- -- -- -- -- -- -- -- 0.4 0.4 0.4 0.4Talc.sup.a 1.2 1.2 1.2 1.2 1.2 1.2 1.2 1.2 1.2 1.2 1.2 1.2TiO.sub.2 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7Carbon Black 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06 0.06ZnO 0.012 0.012 0.012 0.012 0.012 0.012 0.012 0.012 0.012 0.012 0.012 0.012HDPE.sup.b 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1PB (BR 200) Bal. Bal. Bal. Bal. Bal. Bal. Bal. Bal. Bal. Bal. Bal. Bal.__________________________________________________________________________ .sup.a Znstearate-coated. .sup.b Alathon 7815 (DuPont).
Each of the four hindered phenolic antioxidants (Cyanox 1790, Hostanox 03, Irganox 1010 and Naugard XL-1) was used in combination with one of the three co-stabilizers (Cyanox 1212, Seenox 412S and Hostanox SE-10). The same gray pigment system was used in all the twelve formulations. The resins were compounded in a Brabender mixing head at 175° C. at 60 RPM for five minutes under nitrogen purge in order to avoid oxidative degradation. Each resin was then compression-molded into 60 mil thick plaque. After transformation in at least 7 days to the stable hexagonal crystal form I of PB, the plaques were immersed in a 95° C. water bath to evaluate long term stability in hot water. Periodically samples were withdrawn and hot air oven stability at 150° C. was determined. The time to reach characteristic tackiness and color change (to yellow-brownish) was taken as the failure point in the oven. The exudation or blooming of stabilizers to the plaque surface was also monitored as a function of storage time in ambient air (23° C.).
Table II shows the oven life after hot water aging as a measure of long term stability for the twelve formulations. Among these formulations 127-4 through 127-8 and 12 showed lower stability than the other seven resins. In later experiments, resins 127-3 and 127-10 showed stabilizer blooming to the plaque surface after 24 days (from compression molding) at ambient temperature and pressure. Due to observation of the blooming tendency of Hostanox SE-10 in gray and black PB formulations, and because Cyanox 1212 is potentially more acceptable than Hostanox SE-10 in a PB resin for potable water pipe, resins 127-9 through 127-12 were not chosen for further development. After considerating all the relevant factors, formulations 127-1 and 127-2 showed the best combination of properties. Plaques of 127-1 and 127-2 have not bloomed in air up to four months.
TABLE II______________________________________Effect of Hot Water Aging of 60-mil Plaques on the OvenStability for Twelve Experimental PB Resin Formulations shownin Table IDaysin95° C. Oven Life (days) at 150° C. for Formulation No.Water 1 2 3 4 5 6 7 8 9 10 11 12______________________________________ 0 59 61 57 62 88 98 75 73 51 57 40 38 10 58 60 46 58 100 100 55 71 46 46 46 37 27 60 57 37 54 101 104 41 62 54 54 41 32 50 64 63 42 55 105 95 34 64 53 53 39 31 120 46 50 34 34 90 65 28 51 39 35 25 23 245 33 40 22 10 14 5 3 15 38 40 19 5 367 23 34 17 7 2 2 2 2 -- 30 17 2 497 -- -- -- 5 0.5 0.5 0.5 0.5 22 -- -- 10 512 9 22 11 -- -- -- -- -- -- 23 13 --______________________________________ | District heating pipes for potable water contain a polymer composition which comprises a butene-1 homopolymer, sterically hindered phenolic antioxidant, lauryl-stearyl thiodipropionate, nucleating agent, mineral filler coated with acid acceptor and pigment. | 2 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention concerns a process for producing acyclic nucleosides, such as, particularly, acyclovir of the below-mentioned formula (IV) and ganciclovir of the below-mentioned formula (V), both being an anti-viral agent. Acyclovir and ganciclovir are compounds having a powerful anti-viral activity, particularly, to herpes virus both in vitro and in vivo, and have already been authorized and sold commercially as an anti-viral chemotherapeutical agent.
2. Discussion of the Background
For the purpose of producing acyclovir or ganciclovir, there has been known, for example, a method of using guanine as a starting material or a method of using 2,6-dichloropurine or 2-amino-6-chloropurine. However, each of the methods has drawbacks in that the desired compound can not be obtained in a high yield, the desired compound can not be obtained easily in a high purity, and the procedures concerned are complicated from the industrial point of view. U.S. Pat. No. 4,199,574; J. R. Barrio et al., J. Med. Chem., 23 572 (1980); and J. C. Martin et al., J. Med. Chem., 26, 759, (1983) .
On the other hand, ribonucleosides such as guanosine, adenosine and inosine have been mass-produced by a fermentation process. In view of the above, it has been an important subject to develop a novel and industrially advantageous process for synthesizing acyclic nucleosides such as acyclovir and ganciclovir from the above-mentioned ribonucleosides.
SUMMARY OF THE INVENTION
Accordingly, an object of the present invention is to provide a novel and industrially advantageous process for synthesizing acyclic nucleosides such as acyclovir and ganciclovir from ribonucleosides mass-produced by fermentation. Other objects will become apparent from the description of the present invention given hereinbelow.
In an aspect of the present invention, there is provided a process for producing an acyclic nucleoside derivative of the formula (I): ##STR1## which comprises reacting a ribonucloside derivative of the formula (II): ##STR2## with an acid anhydride and an ester derivative of the formula (III): ##STR3## in the presence of an acid catalyst.
In another aspects of the present invention, there is provided a process for producing a nucleoside derivative of the general formula (VII): ##STR4## which comprises heating a purine derivative of the general formula (VI): ##STR5## in the presence of an acid catalyst.
Other aspects will become apparent from the description of the present invention given hereinbelow.
DETAILED DESCRIPTION OF THE INVENTION
With the subject in mind, the present inventors have made profound studies on the transglycosilation reactions between guanosine and a derivative of the sugar moiety of acyclic nucleosides. As a result, it has been found that a transglycosilation reaction takes place between the ribose moiety of a ribonucleoside and an ester derivative of a acyclic sugar when an appropriate acid catalyst and a carboxylic acid anhydride are added to a mixture of a ribonucleoside such as guanosine and an ester derivative of an acyclic sugar and the resultant mixture is heated. The present invention has been made on these findings.
That is, the present invention concerns a process for producing an acyclic nucleoside derivative represented by the general formula (I): ##STR6## where B represents a purine base or pyrimidine base which may be substituted, R 1 and R 2 which may be identical with, or different from, each other represent an alkylene group with 1 to 4 carbon atoms which may be substituted with hydroxyl group (s), amino group (s), alkoxyl group (s), silyl group (s), alkoxycarbonyl group (s), acyl group (s) and/or halogen atom(s), X represents an oxygen atom, a sulfur atom, an imino group or a methylene group, and Y represents a hydroxyl group, an amino group, an alkoxyl group, a silyl ether group, an alkoxycarbonyl group, an acyl group or a halogen atom, which comprises reacting a ribonucleoside derivative represented by the general formula (II): ##STR7## where B represents a purine base or pyrimidine base which may be substituted, in the presence of an acid catalyst, with an acid anhydride and an ester derivative represented by the general formula (III): ##STR8## where R represents a hydrogen atom, an alkyl group with 1 to 20 carbon atoms or an aryl group with 6 to 20 carbon atoms, R 1 and R 2 which may be identical with, or different from, each other represent an alkylene group with 1 to 4 carbon atoms which may be substituted with hydroxyl group(s), amino group(s), alkoxyl group(s), silyl group(s), alkoxycarbonyl group(s), acyl group(s) and/or halogen atom(s), X represents an oxygen atom, a sulfur atom, an imino group or a metylene group, and Y represents a hydroxyl group, an amino group, an alkoxyl group, a silyl ether group, an alkoxycarbonyl group, an acyl group or a halogen atom.
The present invention also concerns a process for producing a nucleoside derivative represented by the general formula (VII): ##STR9## where R 1 and R 2 which may be identical with, or different from, each other represent an alkylene group with 1 to 4 carbon atoms which may be substituted with hydroxyl group(s), amino group(s), alkoxyl group(s), silyl group(s), alkoxycarbonyl group(s), acyl group(s) and/or halogen atom(s), X represents an oxygen atom, a sulfur atom, an imino group or a methylene group, Y represents a hydroxyl group, an amino group, an alkoxyl group, a silyl ether group, an alkoxycarbonyl group, an acyl group or a halogen atom, and R 3 and R 4 each represent independently a hydrogen atom, a halogen atom, hydroxyl group, an amino group or a mercapto group, said hydroxyl group, amino group and mercapto group each being, if desired, substituted with an alkyl group, an aryl group, a silyl group or an acyl group, which comprises heating, in the presence of an acid catalyst, a purine derivative represented by the general formula (VI): ##STR10## where R 1 and R 2 which may be identical with, or different from, each other represent an alkylene group with 1 to 4 carbon atoms which may be substituted with hydroxyl group(s), amino group(s), alkoxyl group(s), silyl group(s), alkoxycarbonyl group(s), acyl group(s) or halogen atom(s), X represents an oxygen atom, a sulfur atom, an imino group or a methylene group, Y represent a hydroxyl group, an amino group, an alkoxyl group, a silyl ether group, an alkoxycarbonyl group, an acyl group or a halogen atom, and R 3 and R 4 each represent independently a hydrogen atom, a halogen atom, a hydroxyl group, an amino group or mercapto group, said hydroxyl group, an amino group and a mercapto group each being, if desired, substituted with an alkyl group, an aryl group, a silyl group or an acyl group.
The present invention will now be described specifically illustrating a synthetic process for acyclovir of the formula (IV) and ganciclovir of the formula (V) with reference to Schemes I(a) and I(b). ##STR11##
When, e.g., acetic anhydride and, e.g., p-toluenesulfonic acid monohydrate are added to a mixed solution of guanosine and 2-oxa-1,4-butanediol diacetate, and the resultant mixture is heated at, e.g., 100° C. for, e.g., 24 hours, a transglycosilation reaction takes place between the moiety of guanosine ribose and 2-oxa-1,4-butanediol diacetate. After completion of the reaction, the reaction solution is subjected to, e.g., alkaline hydrolysis, whereby acyclovir of the formula (IV) is obtained. In this transglycosilation reaction, the 7-position isomer of the acyclovir is also formed together with acyclovir. The two isomers can be separated, if necessary, from each other by, e.g., silica gel column chromatography or recrystallization.
On the other hand, when, e.g., acetic anhydride and, e.g., p-toluenesulfonic acid monohydrate are added to a mixed solution of guanosine and acetoxymethyl-2,3-diacetoxy-1-propyl ether, the resultant mixture is heated at, e.g., 100° C. for, e.g., 24 hours, and then the reaction solution is subjected to, e.g., alkaline hydrolysis, ganciclovir of the formula (V) is obtained. Also, in this transglycosilation reaction, the 7-position isomer of ganciclovir is by-produced. The two isomers can be separated, if necessary, from each other by e.g., silica gel column chromatography or recrystallization.
According to the present invention, in what amount an ester derivative of the formula (III) should be used on the basis of a ribonucleoside of the formula (II) is not critical, and usually a ratio of 1-2:1 is chosen.
As for the acid anhydride of the present invention, an organic carboxylic acid anhydride such as acetic anhydride, propionic anhydride or benzoic anhydride or a phosphoric acid anhydride such as pyrophosphoric acid or metaphosphoric acid is used. The amount to be used is from about 1 to about 10 equivalents based on the starting material of the formula (II).
As for the acid catalyst of the present invention, acid catalysts such as organic acids, inorganic acids and Lewis acids, e.g., p-toluenesulfonic acid monohydrate, sulfanilic acid, methanesulfonic acid, trifluoroacetic acid, trifluoroboron ether complexes, sulfuric acid, phosphoric acid, and hydrochloric acid, are in general used. The catalyst is used in an amount from 1 to 20 mol % based on the starting material of the formula (II).
As for the reaction solvent, usual organic solvents such as, e.g., dimethylformamide; dimethylsulfoxide; acetonitrile; carboxylic acid esters such as ethyl acetate and methyl acetate; hydrocarbons such as benzene, hexane and toluene; ethers such as diethyl ether, tetrahydrofuran and dioxane; halogenated hydrocarbons such as dichloromethane, chloroform and dichloroethane; ketones such as acetone and methyl ethyl ketone; are used. If a compound of the formula (II) is soluble in a compound of the formula (III) and an acid anhydride, the reaction of the present invention may be conducted without any solvent.
The reaction temperature is usually selected from within a temperature range of 20° to 200° C., while the reaction time is usually selected from a period of 1 hour to 1 week.
As for the ribonucleoside derivatives of the formula (II), purine nucleosides such as guanosine, adenosine and inosine, pyrimidine nucleosides such as uridine and cytidine, and the derivatives of the base moiety of such nucleoside may be used.
The acyclic sugar ester derivatives of the present invention have the structure as shown by the formula (III), having an acyl group at the terminal end. There can be mentioned, e.g., 2-oxa-l,4-butanediol diacetate as the acyclic sugar ester derivative, which can be, in turn, synthesized by reacting 1,3-dioxolane and acetic anhydride in the presence of a catalytic amount of an acid. Acyclic sugar ester derivatives thus obtained are allowed to react with ribonucleoside derivatives with or without isolation.
A desired reaction product such as acyclovir or ganciclovir can be isolated from the reaction mixture, e.g., by the treatment with an alkaline solution, followed by purification with silica gel column chromatography.
Next, the isomerization reaction will be explained.
In the transglycosilation reaction, as has already been described regarding the production of acyclovir and ganciclovir, when a purine nucleoside such as guanosine, adenosine or inosine is used as the ribonucleoside, the 7-position isomer is formed together with the 9-position isomer.
When the desired compound is a 9-position isomer such as acyclovir, isomerization of the 7-position isomer to the desired compound (a 9-position isomer) is required. The present inventors have made a study thereon, and as a result, found that the expected isomerization reaction may be realized, with the solvent distilled off or replaced with another solvent, or without isolation of the intermediate from the reaction mixture after the transglycosilation reaction by continuing the heating of the intermediate in the presence of an acid catalyst.
As shown in Scheme II, the 7-position isomer can be isomerized by heating in the presence of an acid catalyst, in the absence, or in the presence, of an appropriate solvent into the 9-position isomer such as an acyclovir derivative or a ganciclovir derivative. ##STR12##
As for the solvent for the isomerization reaction, there can be mentioned usual organic solvents such as, e.g., carboxylic acid esters such as ethyl acetate and methyl acetate; hydrocarbons such as benzene, hexane and toluene; ethers such as diethyl ether, tetrahydrofuran and dioxane; halogenated hydrocarbons such as dichloromethane, chloroform and dichloroethane; and ketones such as acetone and methyl ethyl ketone.
The reaction is usually conducted at a temperature of 20° to 200° C., while the reaction time is usually 1 hour to 1 week.
The completion of the isomerization reaction can be confirmed by, e.g., high performance liquid chromatography. The resultant acyclovir and ganciclovir derivatives form crystals and can be isolated easily.
These derivatives give the final products, i.e., acyclovir and ganciclovir by, e.g., alkaline hydrolysis.
EXAMPLES:
Example 1: Synthesis of 9- ((2-acetoxyethoxy) methyl) -N 2 -acetyl guanine and 7-((2-acetoxyethoxy)methyl)-N 2 -acetyl guanine from guanosine (1 of 2).
To 10 g of guanosine, 13 g of 2-oxa-1,4-butanediol diacetate (2 eq.), 36 g of acetic anhydride (10 eq.), 100 ml of dimethylformamide and 0.67 g (2.5 mol %) of p-toluenesulfonic acid monohydrate were added, and the mixture was stirred at 100° C. for 18 hours.
It was confirmed by comparison with authentic samples using high performance liquid chromatography that 9-((2-acetoxyethoxy)methyl)-N 2 -acetylguanine and 7-((2-acetoxyethoxy) metyl) N 2 -acetylguanine had been formed in 48% and 19% yields based on the guanosine, respectively, namely, at a ratio of 2.5:1.
Example 2: Synthesis of 9- ((2-acetoxyethoxy) methyl) -N 2 -acetylguanine and 7-((2-acetoxyethoxy) methyl)-N 2 -acetylguanine from guanosine (2 of 2).
To 10 g of guanosine, 5.2 g of 1,3-dioxolane (2 eq.), 36 g of acetic anhydride (10 eq.), 100 ml of dimethylformamide and 0.67 g (2.5 mol %) of p-toluenesulfonic acid monohydrate were added, and the mixture was stirred at 100° C. for 18 hours.
2-oxa-1,4-butanediol diacetate was in situ formed in the reaction system and, via the same reaction as in Example 1, it was confirmed that 9-((2acetoxyethoxy) methyl)-N 2 -acetylguanine and 7-((2acetoxyethoxy) methyl) -N 2 -acetylguanine had been formed in 46% and 18% yields based on the guanosine, respectively, by comparison with authentic samples using high performance liquid chromatography.
Example 3: Isomerization of 7-((2-acetoxyethoxy)methyl)-N 2 -acetylguanine into 9-((acetoxyethoxy) methyl)-N 2 -acetylguanine.
The reaction mixture obtained in Example 1 was directly subjected to distillation under a reduced pressure of 5 mmHg to remove the solvent, and the syrup residue was stirred at 100° C. for 18 hours, whereby 9-((2-acetoxyethoxy)methyl)-N 2 -acetylguanine and 7-((2-acetoxyethoxy) methyl)-N 2 -acetyl-guanine were obtained at a resulting ratio of 8.4:1.
The resulting reaction mixture was subjected to purification using column chromatography with 100 g of silica gel, whereby 6.7 g of 9-((2-acetoxyethoxy)methyl)-N 2 -acetylguanine was obtained. Yield, 61%.
1 H NMR (300 MHz, DMSO-d 6 ) analytical values: δ, 1.95 (3H, s, Ac), 2.17 (3H, s, Ac), 3.63-3.73 (2H, m, H-3'), 4.05-4.11 (2H, m, H-4'), 5.48 (2H, s, H-1'), 8.13 (1H, s, H-8) .
Mass spectral analytical value: MH + =310.
Example 4: Synthesis of acyclovir from 9-((2-acetoxyethoxy) methyl)-N 2 -acetylguanine.
To 5.0 g of 9-((2-acetoxyethoxy)methyl)-N 2 -acetylguanine was added 50 ml of an aqueous 5% sodium hydroxide solution, and the mixture was sitrred for 24 hours at room temperature for reaction.
The resulting reaction solution was neutralized with 1N hydrochloric acid, and the precipitated crystals were collected by filtration, whereby 3.2 g of acyclovir was obtained. Yield, 92% .
1 H NMR (300 MHz, DMSO-d 6 ) analytical values: δ, 3.47 (4H, brs, H-3' & 4'), 4.66 (1H, brs, OH), 5.35 (2H, s, H-1'), 6.49 (2H, brs, NH 2 ), 7.81 (1H, s. H-8).
Mass spectral analytical value: MH + =226.
Example 5: Synthesis of 9-((1,3-diacetoxy-2-propoxy)methyl)-N 2 -acetylguanine from guanosine.
To 10 g of guanosine, 17.5 g of 1,4-diacetoxy-3-acetoxymethyl-2-oxa-butane (2 equivalent), 36 g of acetic anhydride (10 equivalent), 100 ml of dimethylformamide and 0.67 g (2.5 mol %) of p-toluenesulfonic acid monohydrate were added, and the mixture was stirred at 100° C. for 18 hours for reaction. Subsequently, the solvent was distilled off under a reduced pressure of 5 mmHg, and the syrup residue was stirred at 100° C. for 18 hours.
Subsequently, the syrup was subjected to column chromatography using 300 g of silica gel and purified by eluting with a 7:1 mixed solvent of chloroform and methanol, whereby 6.9 g of 9-((1,3-diacetoxy-2-propoxy) methyl)-N 2 -acetylguanine was obtained. Yield, 51%.
1 H NMR (300 MHz, CDCl 3 ) analytical values: δ, 7.78 (1H, s, H-7), 5.51 (2H, s, H-1'), 4.50-4.06 (4H, m, H-4', H-5'), 2.62 (3H, s, NHAc), 2.03 (4H, s, OAcx2).
Mass spectral analytical value: MH + =382.
Example 6: Synthesis of ganciclovir from 9-((1,3-diacetoxy-2-propoxy)methyl)-N 2 -acetylguanine.
To 5.0 g of 9-((1,3-diacetoxy-2-propoxy)methyl)-N 2 -acetylguanine was added 50 ml of an aqueous 5% sodium hydroxide solution, and the mixture was stirred for 24 hours at room temperature for reaction.
The resulting reaction solution was neutralized with 1N hydrochloric acid, and the precipitated crystals were collected by filtration, whereby 3.0 g of gunciclovir was obtained. Yield, 90% .
1 H NMR (300 MHz, DMSO-d 6 ) analytical values: δ, 8.31 (2H, s, NH 2 ), 7.58 (1H, s, H-8), 5.43 (2H, s, H-1'), 3.62-3.28 (5H, m, H-3', H-4', H-5) .
Mass spectrum analytical value: MNa + =278.
Example 7: Synthesis of 9-((2-acetoxyethoxy)methyl) -adenine (in the formula (I), R 1 =CH 2 , R 2 =(CH 2 ) 2 , X=O, and Y=OH) from adenosine.
To 10 g of adenosine, 12 g of 2-oxa-1,4-butanediol diacetate (2 eq.), 34 g of acetic anhydride (10 eq.), 100 ml of acetonitrile and 0.63 g (2.5 mol %) of p-toluenesulfonic acid monohydrate were added, and the mixture was refluxed with stirring at an elevated temperature for 48 hours for reaction. Then, the solvent was removed by distillation under reduced pressure from the reaction mixture, and the residue was subjected to hydrolysis with aq. NaOH.
After neutralization, purification using the synthetic adsorption resin "SP-207" was carried out, whereby 5.4 g of the desired product was obtained. Yield, 69%.
1 H NMR (300 MHz, DMSO-d 6 ) analytical values: δ, 3.46 (4H, s, H-2' & 3'), 4.50 (1H, brs, OH), 5.25 (2H, s, H-1'), 7.00 (2H, s, NH 2 ), 8.17 (1H, s, H-2), 8.20 (2H, s, H-8) .
Mass spectral analytical value: MH + =210.
Example 8: Synthesis of 9-((2-acetoxyethoxy)methyl)-hypoxanthine (in the formula (I), R 1 =CH 2 , R 2 =(CH 2 ) 2 , X=O, and Y=OH) from inosine.
To 10 g of inosine, 12 g of 2-oxa-1,4-butanediol diacetate (2 eq. ), 34 g of acetic anhydride (10 eq. ), 100 ml of acetonitrile and 0.63 g (2.5 mol %) of p-toluenesulfonic acid monohydrate were added, and the mixture was refluxed with stirring at an elevated temperature for 48 hours for reaction. Then, the solvent was removed by distillation under reduced pressure from the reaction mixture, and the residue was subjected to hydrolysis with aq. NaOH.
After neutralization, purification using the synthetic adsorption resin "SP-207" was carried out, whereby 3.7 g of the desired product was obtained. Yield, 47%.
1 H NMR (300 MHz, DMSO-d 6 ) analytical values: δ, 3.44 (4H, s, H-2' & 3'), 4.30 (1H, brs, OH), 5.27 (2H, s, H-1'), 8.05 (1H, s, H-2), 8.31 (2H, s, H-8).
Mass spectrum analytical value: MH + =211.
Example 9: Synthesis of 9-((2-acetoxyethoxy) methyl) -N 2 -acetylguanine and 7-((2-acetoxyethoxy) methyl)-N 2 -acetylguanine from guanosine.
To a mixture of 252.26 g of acetic anhydride and 52.36 g of 1,3-dioxolane was added 6.70 g of p-toluenesulfonic acid monohydrate. The mixture was stirred for 1 hour, added with 100 g of guanosine, and stirred at 100° C. for further 24 hours.
It was confirmed that 9-((2-acetoxyethoxy) methyl) -N 2 -acetylguanine and 7-((2-acetoxyethoxy) methyl) -N 2 -acetylguanine had been formed in 46% and 31% yields, respectively, by comparison with authentic samples using high performance liquid chromatography. | Herein is disclosed a novel and industrially advantageous process for synthesizing acyclic nucleosides such as acyclovir and ganciclovir from ribonucleosides, which process comprises adding an acid catalyst and an acid anhydride to a solution of a ribonucleoside such as guanosine and an ester derivative of an acyclic sugar, and heating the mixture, whereby a transglycosilation reaction takes place between the ribose moiety of the ribonucleoside and the ester derivative of the acyclic sugar. | 2 |
CROSS-REFERENCE
[0001] Applicant claims priority from U.S. Provisional application Ser. No. 60/653,734 filed Feb. 17, 2005.
BACKGROUND OF THE INVENTION
[0002] Natural gas is the most common type of hydrocarbon that is in a gaseous state at common environmental temperatures (e.g. 8° C.). Natural gas is well recognized as a low cost, easily-handled and clean burning fuel, as it is often priced below liquid oil, it can be distributed to households and businesses by pipeline, and it creates little emissions other than carbon dioxide. Natural gas is produced at many locations in much larger quantities than can be used locally, and it is transported to faraway customers by cooling it as to −160° C. to produce LNG (liquefied natural gas). The LNG is transported in tankers that each has a capacity of more than 50 million standard (atmospheric pressure and environmental temperature) cubic feet of natural gas, to far away receiving locations. The receiving locations are usually large facilities in developed countries where the large amounts of natural gas can be sold at market prices. The owners of the large LNG receiving facilities spend large amounts to provide extensive distribution pipelines for the gas, and the owners enter into long term (20 plus years) contracts with the suppliers of LNG.
[0003] There is a demand for natural gas in isolated communities of developing countries, with many of such communities being located near ocean coasts. Some examples are the islands of Indonesia and the Phillippines. Although gas could be supplied by LNG tankers to such isolated communities, the demand at each community is too small to justify the cost of a facility that can offload and regas (heat) the large amount of LNG carried by each tanker, and LNG suppliers generally are not interested in providing additional small tankers. A system that enabled natural gas to be provided to isolated coastal communities, would be of value.
SUMMARY OF THE INVENTION
[0004] In accordance with one embodiment of the invention, an economical system is provided for distributing natural gas to each of a plurality of local coastal stations positioned in the vicinity of costal communities. The system includes a local supply station that supplies the natural gas to shuttle boats, or barges that each has a limited storage capacity. Each barge sails or is towed to one or more local coastal stations where the natural gas is unloaded to a receiving facility on a local coastal station. The local coastal station distributes the natural gas to customers lying in the vicinity of the local coastal station. Where the natural gas has been delivered as LNG (liquefied natural gas) by a tanker (storage capacity of at least 50 million standard cubic feet of natural gas) to the local supply station, with the gas having been cooled to about −160° C. to constitute LNG, the supply station merely stores the LNG and offloads LNG to the barges. The barges are designed to carry LNG, and the barges or coastal stations have regas equipment for heating the LNG to gasify it and to heat it, preferably to at least −1° C., so the gaseous warmed natural gas can be delivered though pipelines to customers in the vicinity of the local coastal station. Where the natural gas has been produced from an underground reservoir at the supply station, the gaseous natural gas is delivered to barges that are constructed to carry CNG (compressed natural gas) to the local coastal stations.
[0005] The novel features of the invention are set forth with particularity in the appended claims. The invention will be best understood from the following description when read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 is a plan view of a gas distribution system for economically providing natural gas to numerous isolated coastal communities.
[0007] FIG. 2 is an isometric view of a local coastal station, and showing in phantom lines a shuttle in the process of offloading LNG from the shuttle into the local coastal station.
[0008] FIG. 3 is a plan view of a gas distribution system of another embodiment of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0009] FIG. 1 shows a distribution system 10 for distributing natural gas (hydrocarbons that are gaseous at environmental temperatures such as 8° C. and atmospheric pressure) to each of a plurality of local coastal stations 12 , 14 that lie in the vicinity of small coastal communities 16 , 18 that are usually separated from each other by a plurality of kilometers. Each community generally includes less than one million people within 20 kilometers of the coastal station. The natural gas has been produced from underground (under the land and/or the sea) reservoirs that contain significant quantities of natural gas. Such reservoirs usually contain significant amounts of liquid oil (hydrocarbons that are liquid at 8° C. and atmospheric pressure) that is more easily transported to far-away customers and that is therefore more valuable to the hydrocarbon producer. Until the last few years, such produced natural gas which could not be delivered by short pipelines to local communities was often flared (burned just to get rid of it). More recently, the price of natural gas has risen so it is economical to transport natural gas to far away customers.
[0010] Currently, natural gas has been transported by cooling the natural gas to below the temperature at which it is liquid at atmospheric pressure, such as −160° C. (−256° F.) to create LNG (liquefied natural gas), and loading it into special insulated tanks on an LNG tanker. Large tankers that can store at least 50 million cubic feet of standard gas (gas at an environmental temperature such as 8° C. and atmospheric pressure) have been used. The receiving station was provided with facilities for unloading all of the LNG from the tanker in a short time such as a few days, because the rental rate for such tankers is about $100,000 per day. The receiving station also had facilities for storing the LNG and regasing it (heating the LNG to gasify it) quickly and for distributing all of the natural gas to customers. The owners of the receiving station typically entered into contracts requiring them to purchase large quantities of natural gas for long periods such as over 20 years, and the producer would enter into such contracts before building or acquiring the gas liquefying facility and tanker(s). The receiving stations were usually located in developed countries at locations with access to large cities.
[0011] There is a great demand for natural gas in smaller isolated communities. Natural gas can cost less than liquid oil, it is easily distributed limited distances by pipeline, and it has limited emissions (substantially only carbon dioxide). Producers who fill tankers with LNG have previously ignored such isolated communities, largely because of the limited demand for natural gas in each isolated community. In accordance with the present invention, applicant provides gas distribution systems that allow natural gas to be economically distributed to such isolated communities, at least when such communities lie in the vicinities of ocean coasts.
[0012] The gas distribution system 10 shown in FIG. 1 includes an LNG tanker 20 that carries large amounts (at least 50 million standard cubic feet) of LNG (liquefied natural gas) from a distant LNG source 22 to a local supply station 24 . At the local supply station 24 , a mass of LNG is offloaded from the tanker to a storage facility 30 of the station, which includes insulated tanks 26 where the very cold LNG is stored. It may take a few days to unload the LNG from the tanker. The offloaded LNG is not heated to turn it into gas, as has been previously done at LNG tanker receiving stations, but it is kept cold and liquid as by the use of refrigeration equipment 32 and highly insulated tanks. The local supply station may be located on land or in the sea, so it is not necessarily on or close to a coast.
[0013] The gas distribution system also includes LNG barges, or shuttle boats such as 40 that carries LNG from the local supply station 24 to at least one of the local coastal station 12 , 14 that lies at the coast or shore 84 of a sea 44 , and in the vicinity of a community 16 , 18 that consumes natural gas (either directly or by consuming electricity produced using natural gas as fuel). The shuttle boat 40 has an LNG-holding capacity less than 50% and usually less than 25% of the capacity of the tanker.
[0014] At intervals, the shuttle boat 40 sails to the local supply station 24 , where insulated tanks 50 on the shuttle boat receive LNG that has been stored at the local supply station. The shuttle boat then sails away to one of the local coastal stations such as 12 . At the local coastal station, the LNG is heated to regas it and the gaseous hydrocarbons are transferred through an underwater conduit 52 to a gas storage facility of the coastal station (which may comprise a network of pipelines 54 ). In FIG. 2 , the local coastal station includes a floating structure 60 that is moored to the sea floor 62 as by a turret 64 moored by catenary lines, to allow the structure to weathervane, or the structure is spread moored. FIG. 2 shows a shuttle boat 40 that does not carry LNG heating equipment (although it could) at 61 , but the floating structure 60 of the coastal station does carry such equipment 63 . Such heating equipment for regasing includes a heat transfer system 68 that has a hose or pipe 66 that takes in sea water and another hose or pipe 70 that releases cold water to the sea, or that uses ambient air to heat the LNG. Heat transferred away from the water is used to heat the LNG so it becomes a gas, and to further heat the very cold gas to a temperature, preferably of at least −10° C. and preferably warmer, so large amounts of ice do not form on pipes that carry the gas.
[0015] In FIG. 2 the floating structure carries a power plant 74 that generates electricity, using hydrocarbon gas as fuel. The electricity is passed though a swivel 80 on the turret 64 and through an underwater cable 82 to shore 84 ( FIG. 1 ) where the electricity is distributed to customers. In addition, gaseous hydrocarbon is passed though a swivel 90 ( FIG. 2 ) on the turret and through an underwater pipeline 92 to the shore where it is distributed to customers. If the shuttle boat capacity is much greater than the demand for natural gas from the local coastal station 12 , then the shuttle may sail away to a next local coastal station 14 ( FIG. 1 ) to unload LNG at the second station. Each shuttle boat may be self propelled, or may be pulled by a tugboat. However, it is desirable that all shuttle boats be of the same design to minimize costs. A shuttle boat can be used to store additional LNG at the local supply station.
[0016] FIG. 3 shows a system 110 in which a local supply station 112 produces natural gas from an underground (under the land or the sea) hydrocarbon reservoir 114 that contains natural gas. Although it would be possible to refrigerate the natural gas to turn it into LNG (liquefied natural gas) so large quantities could be carried in a shuttle, applicant prefers to not refrigerate the gas, but to use shuttles 120 that have pressure tanks 122 that carry highly pressurized natural gas in a gaseous state (e.g. at 3000 psi). For a given size shuttle, the mass of natural gas that can be carried by a shuttle boat is less for a shuttle that carries CNG (compressed natural gas) than for a shuttle that carries LNG (liquefied natural gas). However, the fact that the natural gas does not have to liquefied and later regassed, usually makes it more economical to transport CNG in the shuttle boat for short distances. Where the local coastal stations 130 , 132 are close to the local supply station 112 , such as no more than 400 kilometers away, so a shuttle boat one-way trip can be accomplished in one day, the limited storage capacity of the CNG shuttle is largely compensated for by the faster loading and unloading of the shuttle boat and by more trips of the shuttle boat between the supply station 112 and a local coastal station 130 and/or 132 , and possibly by using more but cheaper shuttle boats for a given gas distribution system.
[0017] The local supply station 112 is shown as including a floating production unit 140 that carries equipment 142 for processing produced hydrocarbons. Natural gas is stored under pressure in tanks 144 , and is offloaded to a shuttle boat at 120 A when the shuttle boat returns. The storage capacity in tanks 144 is preferably at least 5 million standard cubic feet of natural gas, and the storage capacity is preferably greater than the storage capacity in a single shuttle boat.
[0018] A natural gas distributing system can be set up at minimal cost by establishing a local supply station and a limited number of coastal stations such as one of them. Where the local supply station obtains natural gas by producing it from a local hydrocarbon reservoir, the cost for the local supply station can be minimal because limited storage capacity is required and no refrigeration system is required. In that case, the local supply station will be set up in the vicinity of a hydrocarbon reservoir that produces large amounts of gaseous hydrocarbons. The local supply may be located offshore or onshore, and may be connected by a pipeline to a production facility lying over a reservoir. Where the local supply station receives LNG from a distant source, the initial cost for the local supply station is greater because it usually must have sufficient LNG storage capacity to store all of the LNG offloaded from a large tanker (minus the amount of LNG that is regassed while the tanker is offloaded). It is possible to make arrangements with an LNG supplier so a tanker arrives with a new shipment of LNG only when needed (which will be more frequent when the system expands). The initial cost for an LNG local distribution system is greater because the shuttle boat(s) or local station(s) must have heating, or regas, facilities. However, once other local communities see that natural gas is available locally, they are more likely to advance funds to build additional coastal station to receive LNG or CNG.
[0019] FIGS. 4 and 5 show a system 160 which includes a local supply station 162 that has insulated tanks 164 that store LNG. The local supply station 162 is shown as including a floating structure 170 and a spread mooring facility 172 that includes lines 174 that extend to the sea floor. The floating structure has tanks 176 that are not insulated and that store liquid hydrocarbons (hydrocarbons that are liquid at ambient temperatures). The floating structure also has a power plant 182 that can use gaseous or liquid hydrocarbons as fuel to produce electricity. The electricity is delivered along an in-sea power cable 184 having a portion on the sea floor 185 , to a shore-based distribution facility 186 that lies near a coast 188 and that distributes electricity to consumers.
[0020] The reason for storing a considerable amount of liquid fuel (e.g. 1 week of diesel fuel for the power plant) is to provide a reserve to energize the power plant 182 in the event that gaseous hydrocarbons are not avoidable. It is much less expensive to provide uninsulated tanks 176 to store LNG, than to provide perhaps two additional insulated tanks similar to 164 and a refrigeration system to keep the stored LNG liquid for a long period of time. It is noted that a refrigeration system generally is not provided for the tanks 164 in a case where they receive LNG from a tanker 190 . This is because it is generally desirable to immediately heat such LNG which has been offloaded to the floating structure 170 , for use in the power plant and to provide CNG (compressed natural gas) to shuttles that deliver it to a local coastal station. A valve structure 192 is controllable to direct natural gas from one of the tanks 164 (after the LNG has been warmed so it is gaseous) to the power plant 182 , or to direct liquid hydrocarbons from a tank 176 to the power plant when warmed LNG is not available at the local supply station.
[0021] Thus, the invention provides systems for bringing natural gas to local communities that are in the vicinity (e.g. within 20 kilometers) of an ocean coast. This is done by providing a local supply station which receives large amounts of natural gas, either as LNG from tankers, or as gaseous hydrocarbons from a local hydrocarbon reservoir. Where the natural gas is LNG received from a tanker, the local supply station stores the LNG in insulated tanks and offloads it to shuttle boats that carry the LNG over the sea to facilities at local coastal stations. At a local coastal station the LNG is heated to regas it, by regas equipment at the local coastal station, or possibly by regas equipment on the shuttle boat. Where the natural gas is produced from a reservoir at the local supply station, the natural gas is preferably compressed and the CNG (compressed natural gas) is carried by shuttles with CNG-holding tanks to the local coastal stations.
[0022] Although particular embodiments of the invention have been described and illustrated herein, it is recognized that modifications and variations may readily occur to those skilled in the art, and consequently, it is intended that the claims be interpreted to cover such modifications and equivalents. | An economical system provides gaseous hydrocarbon to numerous locations ( 16, 18 ) that are each in the vicinity of an ocean coast, such as islands in a developing country, so the coastal inhabitants have access to low cost, easily supplied by pipeline and clean-burning natural gas. The system includes a local supply station ( 24 ), or hub, that stores natural gas, as by receiving LNG (liquefied natural gas) that has been liquefied by cooling it to −160° C., from a large tanker ( 20 ) having a storage capacity of over 50 million standard cubic feet of natural gas. Shuttle boats ( 40 ) that each has a much smaller LNG storage capacity than the tanker, load LNG from the local supply station, carry it to one of a plurality of local coastal stations ( 12, 14 ), heat the LNG to produce gaseous hydrocarbons, and transfer the gaseous hydrocarbons to an offshore receiving facility of the local coastal station. The gaseous hydrocarbons are then used by the local coastal station as to distribute gaseous hydrocarbons to residents of the island or to fuel an electricity generating plant. | 8 |
FIELD OF THE INVENTION
This invention relates to a method and apparatus for analyzing strains in an object and, more particularly, to light interferometry method and apparatus for analyzing strains in an object in any of a plurality of directions.
DESCRIPTION OF THE PRIOR ART
It is important in many commercial settings to be able to test an object for strains which occur when the object is stressed. Such techniques detect subsurface defects, can predict premature failure and improve and maintain product reliability and quality. Examples of manufactured products which are tested in these ways are automotive and truck tires, objects subjected to internal pressures such as pressure vessels and metal and plastic castings, and laminated panels such as aircraft wings.
One technique for performing such testing is holographic interferometry. With such a technique, an object is illuminated with coherent light and the interference pattern creates between light reflected from the object and a refering beam of coherent light is recorded on a photographic media. The object is then stressed, as by changing the ambient pressure or temperature and the resulting interference pattern is recorded as a second exposure on the photographic media. When the media is developed to form a hologram, and the hologram is illuminated with an appropriate reconstructing light beam, an image of the illuminated object is reconstructed having superimposed fringe lines which result from the interference between the two interference patterns created during the two exposures, and represent contours of equal displacement of the object surface between the exposures. These fringes make the existence of undesirable strains immediately obvious. Holographic interferometry, however, loses much of its usefulness in the presence of even the slightest movement of the whole test object between the unstressed and stressed conditions. Under industrial conditions, such movement of the object to be tested may be unavoidable. Additionally, fringes are present in the reconstructed image resulting from non-anomolous overall strain of the object and changes in the index of refraction of the media between exposures, making it difficult to interpret the meaningful fringes.
Another technique for analyzing strains in an object is shearography. This technique relies upon the simultaneous production of two focussed images of the test object under both unstressed and stressed conditions. As disclosed in U.S. Pat. No. 4,139,302, to Hung and Grant, assigned to the assignee of this patent application, the two images may be created by a single camera by providing a wedge over one-half of the camera lens. Half of the light scattered from any point on the object being tested is focussed at one place in the image plane while the other half of the light scattered from that point on the object is focussed at another place in the image plane. The result is that the light scattered by all points on the test object creates an interferogram. When two interferograms formed of the object in two states of stress are caused to interfere with one another, for example, by exposing the same photographic emulsion to both interferograms, the result is an interference pattern (or "shearogram") containing fringes denoting contours of constant spatial rate of change of surface deformation. Because the fringes have a constant optical intensity over the shearogram, it may be necessary to perform coherent optical processing of the shearogram to filter out the higher orders of interference and to render the fringes visible. Shearography typically solves the difficulties associated with strain analysis testing under industrial conditions, because the results are not affected by whole body translations of the test object.
The use of a wedge on the camera lens shears the image in only one direction. Therefore, strains may only be detected parallel to the direction of displacement of the sheared images. A two wedge camera lens as disclosed by Y. Y. Hung and A. J. Durelli in "Simultaneous Measurement of Three Displacement Derivatives Using a Multiple Image-Shearing Interferometric Camera", Journal of Strain Analysis, volume 14, no. 3, pages 81-88, 1979, permits the detection of strains in two chosen directions and in the direction bisecting the angle between these two directions. In the coherent processing step the image may be spatially filtered to evidence strains in one of the three directions to the exclusion of the other two directions. Furthermore, by appropriate placement of photographic stops in the aperture of the Fourier transformation plane created during processing, selected rates of spatial derivatives may be detected. This method is disclosed by Y. Y. Hung, et al. in "Full-Field Optical Strain Measurement Having Postrecording Sensitivity and Direction Selectivity", in Experimental Mechanics, volume 18, no. 2, pages 56-60, February 1978.
A more complete and better understanding of the strains induced in the test object by given stress conditions is possible when the strains may be detected in any of a large number of possible directions rather than only a limited few. Consequently, a need exists for improvements in shearographic techniques which will permit the analysis of strains oriented in a large number of directions from a single shearographic image.
SUMMARY OF THE INVENTION
The present invention provides a method and apparatus which satisfies the aforementioned needs. According to one aspect of the invention, a shearographic apparatus is provided wherein the focussing/shearing optical element in the imaging camera comprises a focussing optical element, typically a lens, and a diffraction grating covering the focussing optical element, with its lines arranged in a plurality of directions. The grating produces multiple images of the object displaced from one another which interfere to form a first interferogram on a photographic plate. When the object is stressed a second interferogram is formed and the two interferograms interfere with each other to form a shearogram. The shearogram can be optically transformed and filtered in the Fourier image plane to permit imaging of only those strains occurring in a given desired direction. The same result may be obtained by storing the interferograms resulting before and after the application of stress conditions in a computer memory, and programming a computer to perform the filtering in the desired directions. The diffraction grating may have straight lines running in two orthogonal directions, radial lines emanating from a common center, or circumferential lines created by concentric circles. The focussing/shearing optical element can be created in the form of a holographic optical element.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects, advantages and applications of the present invention are disclosed in the following detailed description of several preferred embodiments of the invention. The description makes reference to the accompanying drawings in which:
FIG. 1 is a schematic view of apparatus for the creation of a shearographic image according to the present invention;
FIGS. 2(A-C) illustrate three alternative diffraction gratings for use with the apparatus of the present invention;
FIG. 3 shows a playback apparatus for use with the shearographic images created by the apparatus of the present invention; and
FIG. 4 shows an alternative playback apparatus utilizing optical serving of a transformed image and a computer for analysis.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
In a preferred embodiment of the apparatus of the present invention shown in FIG. 1, the apparatus 10 is shown to consist of a source of coherent light 12, such as a laser, a focussing lens 14 having a focal length F, a diffraction grating 16, and a photographic emulsion 18 placed in the focal plane of lens 14, a distance F 2 behind focussing lens 14. Apparatus 10 is used to perform a strain analysis on object 20.
A lens 24 transforms the coherent light produced by light source 12 to a diverging wavefront 22 which illuminates a section of the surface of object 20. The surface of object 20 is denoted in its relaxed condition by solid line 26 and in its stressed condition by dashed line 28.
The light scattered by point P 1 (denoted by 30) on the surface 26 of the relaxed test object 20 is focussed by lens 14 to the focal plane 32. This light is also sheared by diffraction grating 16 before reaching photographic emulsion 18 in imaging plane 32. Each light ray striking grating 16 is split into a plurality of rays which eventually reach plane 32. The actual number of rays created by grating 16 depends upon the type of diffraction grating used. However, for each ray deviated by a given angle from its direction of travel (positive order), there is another ray deviated by a negative angle from that same direction of travel (negative order). The shearing accomplished by diffraction grating 16 may be performed either before or after the light passes through imaging lens 14. Because of the configuration of lens 14 and diffraction grating 16, the light scattered from point P 1 (denoted by 30) on the relaxed test object surface is focussed to a plurality of points 34 lying in image plane 32, including point I (denoted by 34'). The shearing performed by diffraction grating 16 causes a plurality of laterally translated focussed images in plane 32, which combine to create fringes in plane 32.
When the object 20 is stressed, all of the light being focussed at point I (34') in image plane 32 emanates from other points on the stressed surface 28 of test object 20. One such point, P 2 , is denoted by the numeral 36. Points P 1 and P 2 are not necessarily the same point. The light from point P 2 (36) is also sheared to additional points (not shown) in plane 32.
Depending upon the relative path lengths transversed by the light scattered to point 34', the wavefronts creating the fringes in photographic emulsion 18 in image plane 32 can range from being completely in phase to completely out of phase. This will result in fringes ranging from dark to light, depending upon whether the interference at point 34' is constructive, destructive or some intermediate level.
Diffraction grating 16 shown in FIG. 1, consists of two families of parallel straight lines orthogonal to one another and will therefore create shearing of the image in two orthogonal directions. The interference fringes created in photographic plate 18 after the photographic emulsion has been developed can be analyzed to determine the strain created in either of these two orthogonal directions. The apparatus for accomplishing this directional operation will be subsequently described.
Diffraction grating 16 may take any of a variety of forms. A few of the possible forms are shown in FIGS. 2A-C. FIG. 2A shows diffraction grating 16 in the form of a series of radial lines 38 emananting from a common center 40. It is apparent that these radial lines define a large number of directions, permitting the image recorded in emulsion 18 of FIG. 1 to be sheared in the large number of directions perpendicular to these radial lines.
The radial line configuration such as that shown in FIG. 2A has variable spacing ranging from very small spacing between lines 38 near center point 40 to relatively large spacing near the edges of diffraction grating 16. This may undesirably affect the quality of the image by permitting the detection of an unacceptably wide range of strain levels. A grating creating more nearly uniform radial line spacing is shown in FIG. 2B. Here, diffraction grating 16 contains a first set of radial lines 38 emanating from a center point 40 as in FIG. 2A, supplemented by another set of radial lines 42 which do not reach to the central point 40, but rather extend only in the outer portions of diffraction grating 16, say only the outer half of the distances defined by the rays 38 emanating from center 40.
Yet another configuration for diffraction grating 16 is shown in FIG. 2C. A family of concentric circular lines 44 centered upon point 40 and having uniform spacing creates a highly uniform family of lines capable of shearing the image in all directions.
The diffraction gratings 16 shown in FIGS. 1 and 2 can be created holographically and may constitute either amplitude or phase diffraction gratings. The amplitude diffraction gratings will contain alternating lines of transmissivity ranging from 0% (dark lines) to 100% (transparent lines). Holographic techniques can also be used to create phase holograms, by bleaching the dark lines to leave only nonuniformities in the holographic emulsion, thereby creating nonuniformities in the emulsion's index of refraction.
Alternatively, phase diffraction gratings can be created by the ruling of very fine lines on a plate such as a glass plate. The diffraction gratings can be either square wave gratings, where very abrupt changes in dark to light or in index of refraction are created, or sinusoidal diffraction gratings, wherein the intensity of the lines or the index of refraction varies sinusoidally throughout the holographic emulsion. For this application, sinusoidal diffraction gratings are to be preferred because they introduce fewer higher order frequencies into the resulting shearographic image. Phase diffraction gratings have the further advantage in this application of suppressing the zero order diffraction, splitting the impinging wavefront equally into +1 or -1 orders if the diffraction grating is sinusoidal. Suppression of the zero order diffraction can be important for use with some forms of the apparatus.
FIG. 3 of the drawings shows a form of playback apparatus for displaying spatially filtered shearographic images, thereby allowing analysis of strains in desired directions. Emulsion 18 is placed in the imaging plane of imaging lens 46 located the focal distance F 3 away from lens 46, thereby creating an image in image plane 48 such as a plate of ground glass. A spherical wavefront 52 is created by light source 50, the wavefront impinging on transforming lens 54. Lens 54 produces a converging wavefront 56 which focusses at Fourier plane 58 located the focal distance F 2 away from lens 54. The converging wavefront 56 created by transforming lens 54 passes through emulsion 18. Therefore, the image created at Fourier transform plane 58 is the Fourier transform of the image contained in emulsion 18. That fact permits the spatial and directional filtering of the shearographic images contained in emulsion 18. As illustrated in FIG. 3, a mask containing a thin slit 60, centered about the system's optical axis 62, permits light at plane 58 to pass through imaging lens 46 and thence to imaging plane 48.
Through proper choice of the length, extent, and angular orientation of slit 60, a range of strain directions, a range of strained magnitudes and a particular direction of strains may be chosen for presentation. For example, to block low frequencies which may exist in the image contained in emulsion 18, a circular stop, centered on optical axis 62 may be used. On the other hand, if there is no interest in strain levels greater than a predetermined amount, slot 60 may be limited to prevent the higher frequencies in Fourier plane 58 representing these higher strain levels from passing through imaging lens 46 to image plane 48. It will be clear to one skilled in the art that the image presented at image plane 48 may be interpreted by a human operator, by orientation of slit 60 to find features of interest.
An alternative approach 3 shown in FIG. 4 of the drawings. Features common to FIGS. 3 and 4 are numbered identically. As explained in connection with FIG. 3, a Fourier transform of the image contained in emulsion 18 is produced at Fourier image plane 58, located the focal distance F 2 of lens 54 from lens 54. At plane 58 in FIG. 4, an optical stop having a single hole 64 transmits the light representing a direction represented by angle φ and the spatial frequency represented by the distance ρ to an optical imaging device 66, such as a vidicon tube. The signals measuring the transmitted light intensity passing through hole 64 are sent to computer 68. As shown symbolically, computer 68 can control the position of hole 64 by sending appropriate signals over line 70 to a control mechanism located at plane 58.
As a further alternative, the interferograms created in plane 32 of FIG. 1 may be optically sampled by imaging device 72 which scans the image created on a glass plate (not shown) substituted for emulsion 18 in plane 32, both before and after the imposition of deforming forces upon test object 20. These images can be sent to computer 74 where they are digitized, stored separately in computer memories, and added to create a resulting interference pattern. The interference pattern is then analyzed by a properly programmed computer 74 to perform the spatial and directional filtering accomplished optically in Fourier plane 58 of the apparatus shom in FIG. 3. If the images presented in plane 32 shown in FIG. 1 are to be optically sensed, one skilled in the art will appreciate that nonlinear processing of the interferogram images, such as might be accomplished by a properly programmed computer can be used advantageously to improve the contrast of the images in plane 32. The use of phase diffraction gratings when optically sampling the interferograms created in plane 32 of FIG. 1 provides improved results because the on-axis nature of the optical sampling is not complicated by the presence of zero order diffractions created by amplitude diffraction gratings.
While the foregoing is intended to present preferred embodiments of the subject invention, the scope of this invention is to be limited only by the following claims. | A method and apparatus for measuring strains in a test object in any of a plurality of directions. The object is illuminated with coherent light so that light is reflected to a focussing lens and a shearing diffraction grating having lines extending in a plurality of directions. The various diffracted orders interfere at the focal plane of the lens and are recorded on a photographic media. The object is then stressed and a second exposure is made on the same media, resulting in interference between the fringes produced on the two exposures. The media is developed as a transparency and subjected to optical processing to detect strain in any direction. | 6 |
FIELD OF THE INVENTION
The invention relates to a toner for developing a static latent image to be used as a copy machine and a printer, and an image forming apparatus.
BACKGROUND OF THE INVENTION
An impurity, particularly a low molecular weight ingredient having a smell, contained in a toner for developing a static latent image usually used in electrophotography tends to cause an undesirable condition such as giving off an unpleasant odor when the container of the toner is opened at the time of the use of the toner.
A heat-fixing method is usually applied for fixing a toner image onto a copy paper sheet. A heat-roller fixing method is widely used as the heat-fixing. Such the method is extremely suitable for fixing since the heat efficiency for fusing the toner image to adhere it onto the image receiving element is very high and the image can be rapidly fixed.
In some cases, however, an unpleasant odor is given to the operator since the toner image is heated so as to release a very small quantity ingredient contained in the toner. Recently, the chance of to use the copy machine or the printer near a person such as in an office is considerably increased. The chance of the domestic use of such the apparatus is also increased. Consequently, the case is increased in which the odor given off from the toner gives unpleasant feeling to the using person using it. The social concern with the smell is recently raised and the bad odor tends to be extremely evaded even though the fragrant is liked.
One cause of the bad odor given off from the electrophotographic apparatus is generation of ozone by corona discharge. However, the odor of ozone is dramatically reduced by technological innovation such as the development of a contact charging method using a roller charging or a brush charging or of a corona charging device in which the ozone generation is considerably inhibited. Consequently, the case of the unpleasant feeling caused by the toner odor is relatively increased.
In a case, a filter for absorbing the odor is attached with the apparatus. However, such the means accompanies a disadvantage in the production cost and a trouble as to the maintenance of the deodorizing function such as periodical exchange of the filter.
A method by means of reducing the impurity in the binder resin has been known as the means for decreasing the odor caused by the toner. For example, Japanese Patent Publication Open to Public Inspection, hereinafter referred to as JP. O.P.I, Nos. 64-70765, 64-88556 and 8-328311 each proposes decreasing the odor by reducing the monomer remained in the binder resin. JP O.P.I. Nos. 7-104515 and 7-104514 each describes that the reducing of the evaporative ingredient is insufficient to inhibit the toner odor and a technology to remove the odor of the raw material since the evaporative matter formed by decomposition of an chemically instable substance contained in a very small amount in the raw material of the binder resin.
JP O.P.I. No. 8-171234 describes that the causing substance of the odor is an oxidation product of benzaldehyde contained in the toner, and discloses the trial for reducing content of benzaldehyde. Moreover, JP O.P.I. No. 9-230628 describes a contrivance for reducing the odor without bad influence on the fixing ability of the toner by reducing the using amount of alkyl mercaptane until the minimum amount necessary for making the basic property of the toner.
JP O.P.I. No. 3-105350 describes an attempt to add an alkyl betaine compound to the toner as a substance capable of reacting with or absorbing the odor substance. Furthermore, JP O.P.I. No. 2-240663 describes a deodorizing method by which the toner is contacted with a deodorant for 5 hours or more in the processes of crashing and classifying of the toner. However, a long producing time is required and the odor given off after the production cannot be reduced by this method.
The countermeasures by the foregoing methods accompany with difficulty since the amount of the odor substance capable of being perceived by man is very small.
It is important, however, to consider the problem of the odor from the viewpoint of that it is difficult to judge the odor is perceived by man as a good smell (fragrant) or a bad odor and a non-smell condition is pleasant or not for man since the perception of man is delicate.
From such the viewpoint, it is necessary to known a technology for precisely evaluating and designing the quality of the odor caused by the extremely small amount of the contained substance according to a objective norm, and to know that what smell given off in what degree is perceived by man as pleasant smell according to the evaluation and the design.
The object of the invention is to precisely evaluate and design the smell given off from the image forming apparatus such as the copy machine or the printer, which are become to be frequently used near man, and to make the smell to a pleasant smell for man. The evaluation and the design of the toner is previously carried out from the viewpoint of that the pleasant smell is given off in the image forming process since the major cause of the smell given off from the image forming apparatus is the toner for developing the static latent image.
SUMMARY OF THE INVENTION
A method is found by the inventors, by which a slight and delicate smell can be objectively evaluated and the standard of the pleasant smell can be defined according to the results of the evaluation. Thus the invention can be attained.
The object of the invention can be achieved by applying any one of the following constituents.
1. A toner for developing a static latent image, wherein a smell of the toner has a cos θ of from 0.990 to 0.998 as to the smell of styrene and a cos θ of from 0.986 to 0.994 as to the smell of n-butyl acrylate in the smell space formed by styrene and n-butyl acrylate.
2. A toner for developing a static latent image, wherein a smell of the toner has a cos θ of from 0.990 to 0.998 as to the smell of styrene and a cos θ of from 0.991 to 0.999 as to the smell of mercaptocarboxylic acid ester in the smell space formed by styrene and mercaptocarboxylic acid ester.
3. An image forming apparatus fixing a toner image onto a recording material by heating, wherein the image forming apparatus emits a fragrant smell having a cos θ of from 0.990 to 0.998 as to the smell of styrene and a cos θ of from 0.986 to 0.994 as to the smell of n-butyl acrylate in the smell space formed by styrene and n-butyl acrylate.
4. An image forming apparatus fixing a toner image on to a recording material by heating, wherein the image forming apparatus emits a fragrant smell having a cos θ of from 0.990 to 0.998 as to the smell of styrene and a cos θ of from 0.991 to 0.999 as to the smell of mercaptocarboxylic acid ester in the smell space formed by styrene and mercaptocarboxylic acid ester.
DETAILED DESCRIPTION OF THE INVENTION
The angle between the vector of the smell causing substance and that of a sample is determined and the cosine of the angle cos θ is calculated. It can be considered that the smell of the sample is nearer the smell of the smell causing substance when the angle of the vector is smaller or the value of the cos θ is larger.
For example, when the vectors of Toner A and Toner B and the reference substance are as shown in FIG. 1, cos θ B is larger than cos θ A in this case. Consequently, it can be concluded that the smell of Toner B is nearer the smell of the reference substance than the smell of Toner A.
In the invention, styrene, a mercatocarboxylic acid ester and n-butyl acrylate are used as the reference substance. As the mercaptocarboxylic acid ester, n-octyl-3-mercaptopropionic acid ester is used.
It has been found by the inventors that a smell different in some degree from, not the same as, the smells of these reference substances is a pleasant smell source so that the working efficiency can be raised. Furthermore, it has been unexpectedly found that the working efficiency is also lowered when the smell is largely different from that of the reference substance. It is considered that the working efficiency is lowered by a sense of incompatibility caused by the smell different from that usually perceived from the copy machine of the printer customarily used even though the reason of such the effect is not cleared yet. It is supposed that the working efficiency of man can be raised by giving the slightly different smell without feeling of the smell difference. Consequently, it is concluded that it is important to control the smell of the toner so that the gradient of the vector as to the reference substance cos θ is within the specified range. Thus the object of the invention is attained.
The working efficiency of man is lowered when the smell is without the range.
The cos θ as to the reference samples in the smell space represents the cos θ measured by the following method.
As the sample for measuring, 0.1 g of a toner is put into a sample bag made of poly(ethylene terephthalate) having a volume of 2 liter.
The sample bag is filled by nitrogen and the bag including the toner is heated for 30 seconds by a hot plate heated at 160° C.
Preparation of Reference Sample
Reference sample of styrene smell: In a 2 liter sample bag, 0.2 ml of saturated styrene gas is put and diluted by nitrogen gas.
The saturated gas is gas taken near the liquid surface in the bottle by a micro syringe. The bottle is stored at an ordinary temperature under a closed condition.
Reference sample of n-butyl acrylate smell: In a 2 liter sample bag, 0.2 ml of saturated n-butyl acrylate gas is put and diluted by nitrogen gas.
Reference sample of mercaptocarboxylic acid ester smell: n-octyl-3-mercaptopropionic acid ester is used as the reference substance. In a 2 liter sample bag, 0.5 ml of saturated n-octyl-3-mercaptopropionic acid ester gas is put and diluted by nitrogen gas. Then the bag is stood for 1 hour.
Measuring Condition
Measuring Apparatus: Fragrance & Flavor Analyzer FF-1
Manufactured by Shimazu Seisakusyo Co., Ltd.
Temperature of sensor chamber: 60° C.
Current amount of sampling: 165 ml/min.
Preliminary sampling period: 10 sec.
Sampling period: 45 sec.
Temperature of collecting tube: 40° C.
Dry Purge
Temperature: 40° C.
Current amount: 500 ml/min.
Period: 45 sec.
Desorption
Temperature of collecting tube: 220° C.
Current amount: 20 ml/sec
Period: 90 sec.
Measuring times for one sample: 5
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the vector of the smell of the toner together with that of the reference substance.
1. Vector of the smell of Toner A
2. Vector of the smell of the reference substance
3. Vector of the smell of Toner B
FIG. 2 shows a schematic constitution of the image forming apparatus of an example of the embodiment of the invention.
FIG. 3 shows a cross section of an example of the fixing device to be used in the invention.
1. Semiconductor laser light source
2. Polygon mirror
3. fθ lens
4. Photoreceptor
5. Charging device
6. Developing device
7. Transferring device
8. Recording element (Image support)
9. Separation device
10. Fixing device
11. Cleaning device
12. Exposure before charging (PCL)
13. Cleaning blade
DETAILED DESCRIPTION OF THE INVENTION
The materials, the production method and the image forming apparatus usable in the invention are described below in detail.
A method can be applied to attain the smell according to the invention, by which the smell containing the reference substance is reduced so as to be within the specific range by the use of a deodorant. A toner prepared by a polymerization method by which the resin is synthesized in water is preferred rather than a toner prepared by a crushing method by which the resin and the colorant are fused, kneaded and crushed, even though there is no limitation on the method for preparing the toner itself, since the toner prepared by the polymerization method is easily deodorized.
The deodorant to deodorize the unpleasant and unnecessary odor is described bellow.
Extracted Matter of Plant
The extracted matter of plant is an extract or an extracted ingredient originated in plant or an aqueous dispersion of a synthesized substance having a structure the same as the extracted ingredient of plant. In the invention, one capable of deodorizing a sulfur-containing odor substance is preferable as the deodorizing material regarding the extract of plant. For example, a plant extract such as a green tea extract, condensed persimmon tannin and a bamboo extract is preferable. These materials convert hydrogen sulfide or mercaptane to convert to non-odor molecular by chemical decomposition or deodorize the odor molecular by inclusion.
When the deodorant containing a plant extract preferably usable in the invention is prepared from green tea, the crushed raw leaf of green tea is immersed in ethanol. Thus obtained ethanol extract which contains a catechin, a vitamin, a sugar and an enzyme is filtered and concentrated to obtain the deodorant containing the plant extract relating to the invention.
In concrete, the deodorant is one prepared by extracting the raw leaves of green tea by ethanol at a temperature of not more than 80° C., for example, from 50 to 70° C. This solution contains an ethanol-soluble ingredient and a water-soluble ingredient contained in the raw leaf of green tea. The ethanol extract contains a flavanol such as (−)-epicatechin (EC), (−)-epigallocatechin (EgC), (−)-epicatechin gallate (ECg) and (−)-epigallocatechin gallate (EGCg), an enzyme such as an oxidation-reduction enzyme, a transfer enzyme, a hydrolytic enzyme and an isomerase, a glycoside of a flravonol such as flavone, isoflavone, flavonol, flavanone, flavalyl, Orlon, anthoamidine, chalcone and dihydrochalcone, caffeine, an amino acid, a flavandiol, a polysaccharide, a protein and a vitamin, which are almost the same as in the green tea extract. The ingredients of the raw leaf of tea are varied depending on the weather, the atmospheric temperature, the harvest time and the harvest region. Therefore, it is preferable to add synthesized and purified vitamins C and B1 to the ethanol extract in an amount of from 1 to 2% by weight of the solid ingredient contained in the extract for giving a constant and stable deodorizing period to the deodorant and for reinforcing the effect and the ability of the deodorant.
The deodorant relating to the invention is an alcoholic solution containing the catechins, vitamins, sugars and enzymes. The residue of the raw tea leaf after the extraction by alcohol may be contained in the foregoing deodorant. Accordingly, the deodorant relating to the invention can be produced by immersing the crashed raw tea leaves in alcohol for extracting the ingredients of the raw leaf of tea.
Another concrete example of deodorant containing an extract ingredient of plant includes a tree such as Japanese cypress, Aomori hiba, beech tree, cryptomeria, camphor tree and eucalyptus, a herb, mustard, Japanese horseradish, lemon, Chinese quince, mint, clove, Ceylon cinnamon, bamboo, rhizome of iriomote thistle and root of yaeyama palm. The extract or extracted ingredient can be obtained by subjecting the plant body to crashing, pressing, boiling or steam distilling. Concrete examples of the extracted ingredient of the plant or the synthesized substance having the structure the same as that of the ingredient of the extract of the plant include a tropolone such as hinokitiol, a monoterpene such as α-pinene, β-pinene, camphor, menthol, limonene, borneol, α-terpinene, γ-terpinene, α-terpineol, terpinene-4-ol and cineol, a sesquiterpene such as α-cadinol and t-muurolol, a polyphenol such as catechin and tannin, a naphthalene derivative such as trimethylnaphthalene, a long chain aliphatic alcohol such as citronellol, an aldehyde such as cinnamaldehyde, citral and perylaldehyde, and an allyl compound such as a allyl isocyanate. A pyroligneous acid obtained by baking wood is also usable in the invention. When the extracted ingredient of plant or the synthesized substance having the same structure as that of the extracted ingredient of plant is insoluble in water, they can be used in a form of an aqueous dispersion using a dispersant such as a surfactant.
Among the plant extract ingredient deodorants available on the market, for example, F118, manufactured by Fine 2 Co., Ltd., and Dersen, manufactured by Yuukou Yakuhin Kogyo Co., Ltd., are preferably used.
A phytontid deodorant in which at least one of the extract ingredients of plant is a phytontid, is mainly comprised of the plant extract containing the phytontid. The phytontid deodorant is prepared by adding an anionic surfactant, a glycol, a specific surfactant and a host compound to a natural macromolecular substance having a molecular weight of from 15,000 to 2,300,000, which is extracted from a coniferous tree. Such the deodorant completely decomposes chemically and converts the odor substance to another substance by neutralization and inclusion. Biodash D-200, manufactured by Daiso Co., Ltd., available on the market is preferably used.
Enzyme Type Deodorant
As to the deodorant containing an enzyme, many ones containing a biological oxidation enzyme, particularly a certain kind of metal-containing enzyme, have an ability of oxidation decomposing ammonia, an amine, hydrogen sulfide, a mercaptane, indole and a carbonyl compound. Almost all the molecules of the odor substance have a movable hydrogen atom. Therefore deodorization can be realized by dehydrogenating oxidation such the hydrogen atom so as to convert the odor substance to a dimer, an insoluble substance or a nonvolatile substance.
Concrete examples of the enzyme having the deodorant effect include catalase, amylase, protease, lipase, papain, cymopapain and pepsin. The catalase enzyme contains hematoporphyrin and is combined with an apoprotein, in which the electron of the iron atom is in a state of three-valent spin and the nitrogen atom of histidineimidazole is coordinated at the fifth coordination locus. Bio C, manufactured by Console Corporation, and Biodash, manufactured by Daiso Co., Ltd., are preferably used among the enzyme type deodorants available on the market. Metal-phthalocyanine and artificial enzyme type deodorant using the metal-phthalocyanine
The metal-phthalocyanine type deodorant includes an artificial enzyme type deodorant containing the metal-phthalocyanine.
A metal-phthalocyanine derivative having a catalytic activity similar to that of natural enzyme catalase, preferably an iron complex of carboxyphthalocyanine, more preferably an iron complex of octacarboxyphthalocyanine, has an ability of decomposing the odor substance molecule by a reaction mechanism similar to that of catalase.
The use of the metal-phthalocyanine as the deodorant gives the following advantages on the odor decomposition of the odor:
1: The reaction speed and the decomposing efficiency are high
2: The reaction is progressed at an ordinary temperature
3: Possibility of environment prolusion is little since the reaction is carried out in an aqueous system.
4: The life of the catalyst if long since the reaction is a cyclic reaction.
An artificial enzyme can also be used as the deodorant, which is prepared by bonding the metal-phthalocyanine derivative with a macromolecular substance by an ionic bond. Cyclodextrin is preferably used as the concrete example of the macromolecular substance.
Microbe Deodorant
A deodorant using a culture medium liquid of microbe is used as the microbe type deodorant. Examples of the microbe include one of more kinds of microbe selected from Bacillus group, Enterobacter group, Streptococcus group, Rhizopus group and Aspergillus group. A microbe of Nitrosomonas group, Nitrobacter group or Pseudomonus group can also be preferably used. The microbe deodorant is produced by the following procedure: A mixture of composed of 10 parts by weight of the microbe, from 5 to 100 parts by weight of a sugar, from 0.1 to 50 parts by weight of a water-soluble nitrogen compound and from 1,000 to 50,000 parts by weight of water is incubated for a period of from 15 to 40 hours at a temperature of from 20 to 40° C. and an oxygen supplying amount of from 0.02 to 2.0 liter per minute. Then the liquid is subjected to a treatment by a centrifuge. Thus obtained supernatant liquid or the culture liquid is dried to obtain the deodorant. A porous powder such as sawdust may be added in an amount of from 20 to 300 parts by weight to the culture liquid for suspending the microbe. A liquid aldehyde such as glutaraldehyde may be used together with the microbe deodorant. The mixing with the liquid aldehyde is preferred since the deodorizing effect of the deodorant is further enhansed.
Concrete examples of the microbe preferably usable in the invention include a microbe of Bacillus group, particularly Bacillus subtilis (Institute of Applied Microbiology, hereinafter referred to as IAM, 1168), Bacillus natto (Institute for Fermentation Osaka hereinafter referred to as IFO, 3009) as the preferable microbe. Moreover, Bacillus coagulas (IAM 1115) and Bacillus macerans (IAM 1243) are also usable.
As the microbe of Enterobacter group, for example, Enterobacter sakazaki (IAM 12660) and Enterobacter agglonerans (IAM 12659) are usable.
As the microbe of Streptococcus group, for example, Streptococcus faecalis (IAM 1119), Streptococcus cremoris (IAM 1150) and Streptococcus lactis (IFO 12546) are usable.
As the microbe or mould of Rhizopus group, for example, Rhizopus formosaensis (IAM 6250) and Rhizopus oryzae (IAM6006) are usable.
As the microbe of Aspergillus group, for example, Aspergillus oryzae (IFO 4176) and Aspergillus niger (IFO 4066) are usable.
As the microbe of Nitrosomonas group, for example, Nitrosomonas europaea (IFO 4066) is usable.
As the microbe of Nitrobacter group, for example, Nitrobacter agilis (IFO 14297) is usable.
As the microbe of Pseudomonas, for example, Pseudomonas caryophilli (IFO 12950), Pseudomonas statzeri (IFO 3773) are usable.
The microbe deodorant contains the microbe in the dormancy state, an organic acid effective for deodorization, and the enzyme capable of decomposing an organic substance. The microbe converts sugar and alcohol to lactic acid, citric acid or malic acid and produces an enzyme such as amylase, protease and lipase so to decompose an organic substance being the source of odor.
Adsorption of the Deodorant onto the Toner Particle Surface
In the invention, it is preferred that the deodorant is adsorbed onto the surface of the toner particle to maintain the deodorant effect even when the odor ingredient of the toner is exuded out from the interior of the toner particle at the process of drying or after sealing.
When the toner is produced by a polymerization method and salted out and coagulated, it is preferable that the deodorant is dissolved or dispersed in the aqueous medium even though the method for adsorbing the deodorant onto the toner particle is not specifically limited. It is further preferable that the toner particle is treated by the deodorant liquid after removing adhered substances such as the surfactant and the salting-out agent in the later-mentioned filtering and washing processes of the toner. The concentration of the deodorant to be adsorbed is preferably from 0.01 to 10 ppm of the toner. When the amount of the deodorant is less than 0.01 ppm, endurance of the deodorant effect is insufficient and when the amount of the deodorant is more than 10 ppm, the charging property becomes instable.
The producing method of the toner for developing a static latent image according to the invention is described below.
Production Method of the Toner
There is no specific limitation on the production method of the toner relating to the invention. However, a polymerization method, namely a method by which a polymerizable monomer is polymerized in an aqueous medium to form the toner particle, is preferable since the treatment for deodorizing and giving a pleasant smell has a high freeness.
In the invention, the aqueous medium is a medium comprising from 50 to 100% by weight of water and from 0 to 50% by weight of an organic solvent. Example of the organic solvent includes methanol, ethanol, iso-propanol, butanol, acetone, methyl ethyl ketone and tetrahydrofuran. An alcohol type organic solvent capable of not dissolving the resin to be formed is preferred.
An example of production process of the toner relating to the invention is described below.
The production process of the toner is principally composed of the following processes.
1: A multi-step polymerization process (I) for producing a combined resin particle in which a mold releasing agent and/or crystalline polyester is contained in a portion (in the central portion or the intermediate layer) other than the outermost layer.
2: A salting-out/adhering process (II) for forming toner particle by salting-out/adhering the combined resin particles and colored particles.
3: A filtering and washing process for separating the toner particle from the dispersion system of the particle by filtration and removing the surfactant from the toner particle by washing
4: A drying process for drying the washed toner particle
5: A process for adding an external additive into the dried toner particle
The steps are each described in detail below.
Multi-step Polymerization Process (I)
The multi-step polymerization process is a process to produce the combined resin particle by forming a covering layer composed of a polymer of the monomer on a resin particle by the multi-step polymerization.
In the invention, a three or more step polymerization process is preferred from the viewpoint of the production stability and the anti-crush strength of the product.
The two-step polymerization method and the tree-step polymerization method are described below as typical examples of the multi-step polymerization.
Two-step Polymerization Method
The two-step polymerization method is a method for producing the combined particle composed of a central or core portion or core comprising a resin having a high molecular weight and a mold releasing agent; and a outer layer or shell comprising a resin having a low molecular weight. Namely, the combined resin particle produced by the two-step polymerization method is composed of the core and one layer covering the core.
In concrete, a monomer solution is prepared by dissolving the mold releasing agent in the monomer L. The monomer solution is dispersed as oil droplets in an aqueous medium such as a surfactant solution. The dispersion is subjected to a polymerization treatment, the first polymerization step, to form a dispersion of high molecular weight resin particles each containing the mold releasing agent.
Then a polymerization initiator and a monomer L for forming a low molecular weight resin are added to the resin second polymerization step, is applied. The covering layer is formed on the surface of the resin particle by the polymerization of the monomer L in the presence of the resin particle.
(Three-step Polymerization Method)
The tree-step polymerization method is a method for forming a combined resin particle comprising a central portion or a core composed of a high molecular weight resin, an intermediate layer containing the mold releasing agent and an outer layer or a shell. Namely, the combined particle formed by the three-step polymerization method is composed of the core and the two covering layers.
In concrete, a dispersion of resin particles prepared by a usual polymerization treatment, the first polymerization step is added to an aqueous medium such as a surfactant solution. Then a monomer solution prepared by dissolving the mold releasing agent in the monomer M is dispersed into the foregoing aqueous system in a form of oil droplet and the system is subjected to a polymerization treatment, the second polymerization step, to form a covering layer or an intermediate layer comprising a resin, polymer of the monomer M, containing the mold releasing agent. Thus a dispersion of a combined resin particles composed of the high molecular weight resin and the intermediate molecular weight resin.
To thus obtained dispersion of combined resin particle, a polymerization initiator and a monomer L to obtain a low molecular weight resin are added. Then a polymerization treatment of the monomer L is applied in the presence of the combined resin particle to form a covering layer composed of a low molecular weight resin, a polymer of the monomer L, on the surface of the combined resin particle. The foregoing method is preferred since the mold releasing agent can be finely and uniformly dispersed by applying the second polymerization step.
The polymerization method suitable for forming the resin particle or the covering layer each containing the mold releasing agent includes the following method:
A monomer solution composed of the monomer and the mold releasing agent dissolved in the monomer is dispersed in a form of an oil droplet by applying mechanical energy in an aqueous medium in which a surfactant is dissolved in a concentration less than the critical micelle concentration.
The water-soluble polymerization initiator is added to thus obtained dispersion and the monomer is polymerized by a radical polymerization in each of the oil droplets, hereinafter such the method is referred to as “a mini-emulsion method”.
This method is preferred since the effect of the invention can be enhanced. In the method, an oil-soluble polymerization initiator may be used in place of or together with the water-soluble polymerization initiator.
The mold releasing agent dissolved in the oil phase is not released from the oil by the mini-emulsion method in which the oil droplet is mechanically formed, different from a usual dispersing method. Consequently, a sufficient amount of the mold releasing agent can be introduced in the formed resin particle or the covering layer.
There is no specific limitation on the dispersing means for dispersing the oil droplet by mechanical energy. For example, a stirring apparatus having a high speed rotor Cleamix, manufactured by M-tech Co., Ltd., an ultrasonic dispersing apparatus, a mechanical homogenizer, Manton-Goulin homogenizer and a pressure homogenizer are usable. The diameter of the dispersed particle is from 10 to 1,000 nm, preferably from 50 to 1,000 nm, more preferably from 30 to 300 nm.
An emulsion polymerization method, a suspension polymerization method and a seed polymerization method may also be applied for forming the resin particle or the covering layer other than the foregoing mini-emulsion polymerization method. These polymerization methods can also be applied for forming the resin particle constituting the combined resin particle (core particle) or the covering layer each containing no mold releasing agent and no crystalline polyester.
The diameter of the combined resin particle produced by the polymerization process I is preferably within the range of from 10 to 1,000 nm by weight average diameter measured by Electrophoresis Light Scattering Photometer ELS-800, manufactured by Otsuka Denshi Co., Ltd.
The glass transition point Tg of the combined resin particle is preferably within the range of from 48 to 74°, more preferably from 52 to 64°.
The softening point of the combined resin particle is preferably within the range of from 95 to 140° C.
Salting Out/fusion-aAdhering Process II
The process II is a process to obtain an irregular or non-sphere shaped toner particle by simultaneous salting-out and fusion-adhering of the combined resin particles and colorant particles.
The “salting-out” in the invention is a process in which the combined resin particles dispersed in the aqueous medium are coagulated by the effect of a salt. The “fusion-adhering” in the invention is a process to disappear the inter-particle surface between the particles coagulated by the salting-out. The “salting-out/fusion-adhering” means the simultaneous occurrence of the salting-out and the fusion-adhering or an action to simultaneously occur such the processes. For simultaneous occurrence of the salting-out and the fusion-adhere, it is necessary to coagulate the combined resin particles and the colorant particles at a temperature more than the glass transition temperature Tg of the resin constituting the combined resin particle.
In the salting-out/fusion-adhering process, an internal additive particle, fine particles having a number average diameter of primary particle of from 10 to 1,000 nm, of an additive such as a charge control agent may be salted out/fusion-adhered together with the combined resin particles and the colorant particles. The colorant particle may be one previously subjected to a surface modifying treatment. A known agent can be used for the surface modifying.
The colorant particle is subjected to the salting-out/fusion-adhering treatment in a state of dispersed in an aqueous medium. The aqueous medium in which the colorant particle is dispersed is preferably an aqueous solution in which a surfactant is dissolved in a concentration more than the critical micelle concentration.
Although there is no specific limitation on the dispersing means for dispersing the colorant particle, a medium type dispersing apparatus such as a stirring apparatus having a high speed rotor Cleamix, manufactured by M-tech Co., Ltd., an ultrasonic dispersing apparatus, a mechanical homogenizer, a pressure homogenizer such as Manton-Goulin homogenizer and a pressure homogenizer, Gettman mill and a diamond fine mill is usable.
It is necessary for salting-out/fusion-adhering the combined resin particles and the colorant particles to add a salting-out agent or a coagulation agent in a concentration of more than the critical coagulation concentration into the dispersion in which the combined resin particles and the colorant particles are dispersed, and to heat the dispersion by a temperature more than the glass transition temperature Tg.
The suitable temperature range for salting-out/fusion-adhering is from Tg+10° C. to Tg+50° C., preferably Tg+15° C. to Tg+40° C. A water-compatible organic solvent may be added for effective progression of the fusion-adhering.
Filtration and Washing Process
In the filtration and washing process, are applied a filtration treatment for separating toner particles by filtration from the toner particle dispersion obtained by the foregoing process, and a washing treatment for removing the substance adhered to the toner particle such as the surfactant and the salt-outing agent from the cake of the toner particles.
For the filtration treatment, a centrifuge, a vacuum filtration using a Nutsche funnel and a filtration using a filter press are applicable without any limitation.
(Drying Process)
This process is a process for drying the washed toner particles.
A spray dryer, a vacuum freezing dryer a vacuum dryer are usable in this process. A fixed rack dryer, a movable rack dryer, a fluid bed dryer, a rotary dryer and a stirring dryer are preferably usable.
The moisture content of the dried toner particles is preferably not more than 5% by weight, more preferably not more than 2%.
When the dried toner particles are coagulated by a weak attractive force between the particles, the coagulum may be subjected to a powdering treatment. For the powdering, a mechanical powdering machine such as a jet mill, a Henschel mixer, a coffee mill and a food processor is usable.
The toner according to the invention is preferably produced by the following procedure. Namely, the combined resin particles are prepared in the presence of no colorant and a dispersion of the colorant particle is added to the dispersion of the combined resin particle. Thereafter, the combined resin particles and the colorant particles are salted out/fusion adhered.
The polymerization reaction to form the combined resin particle is not hindered since the combined resin particle is produced in a system without the presence of the colorant. Consequently, the anti-offset ability is not degraded and the contamination of the fixing device and the image caused by accumulation of toner is prevented by the use of the toner according to the invention.
No monomer nor oligomer is remained in the toner particle since the polymerization reaction for forming the combined resin particle is surely progressed. Therefore, unpleasant odor is not occurred in the heat fixing process of the image forming apparatus using the toner.
Moreover, the image with a high sharpness can be obtained for a long period since the toner particles have a uniform surface property and a sharp charging amount distribution. In the image forming method comprising a contact heating fixing process, the anti-offset ability and the preventing ability for putting round to the fixing roller can be enhanced while a suitable adhesiveness to the image support or a high fixing strength of the toner image is maintained, and the image having a suitable glossiness can be obtained.
The constituents of the toner production process are described in detail below.
Polymerizable Monomer
A hydrophobic monomer is used as the essential constituent of the polymerizable monomer for forming the binder resin to be used in the invention. A monomer capable of cross-linking is used when it is necessary. It is preferable that at least one kind of monomer having an acidic polar group or a basic polar group is contained as later-mentioned.
(1) Hydrophobic Monomer
Known monomers can be used as the hydrophobic monomer constituting the monomer constituent without any limitation. One or more kinds of the monomers may be used in combination so as to satisfy the required property.
Concrete examples of the usable monomer include a mono-vinyl aromatic monomer, a (metha)acrylate monomer, a vinyl ester monomer, a vinyl ether monomer, a mono-olefin monomer, a di-olefin monomer and a halogenated olefin monomer.
Examples of the vinyl aromatic monomer include a styrene monomer and a derivative thereof such as styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, p-ethylstyrene, p-n-butylstyrene, p-tert-butylstyrene, p-n-hexylstyrene, p-n-octylstyrene, p-n-nonylstyrene, p-n-decylstyrene, p-n-dodecylstyrene, 2,4-dimethylstyrene and 3,4-dichlorostyrene.
Examples of the acryl monomer include acrylic acid, methacrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, ethyl β-hydroxyacrylate, propyl γ-aminoacrylate, stearyl methacrylate, dimethylaminoethyl methacrylate and diethylaminoethyl methacrylate.
Examples of the vinyl ester monomer include vinyl acetate, vinyl propionate and vinyl benzoate.
Examples of the vinyl ether monomer include vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether and vinyl phenyl ether.
Examples of the mono-olefin monomer include ethylene, propylene, isobutylene, 1-butene, 1-pentene and 4-methyl-1-pentene.
Examples of the di-olefin monomer include butadiene, isoprene and chloroprene.
(2) Monomer Capable of Cross-Linking
The monomer capable of cross-linking may be added to improve the property of the resin particle. Examples of the monomer capable of cross-linking include one having two or more unsaturated bonds such as divinylbenzene, dovinylnaphthalene, dovinyl ether, diethylene glycol methacrylate, ethylene glycol dimethacrylate, poly(ethylene glycol) dimethacrylate and diallyl phthalate.
(3) The Monomer having an Acidic Polar Group
Examples of the monomer having an acidic polar group include (a) an α,β-ethylenic unsaturated compound having a carboxyl group —COOH and (b) an α,β-ethylenic unsaturated compound having a sulfonic acid group —SO 3 H.
Examples of the α,β-ethylenic unsaturated compound having the —COOH group of (a) include acrylic acid, methacrylic acid, fumaric acid, maleic acid, itaconic acid, cinnamic acid, monobutyl maleate, monooctyl maleate and their salts of a metal such as sodium and zinc.
Examples of the α,β-ethylenic unsaturated compound having the —SO 3 H group of (b) include sulfonated styrene and its sodium salt, allylsulfosuccinic acid, octyl allylsulfosuccinate and its sodium salt.
(4) The Monomer having a Basic Polar Group
Examples of the monomer having a basic polar group include (i) a methacrylate of a aliphatic alcohol having an amino group or an ammonium group and from 1 to 12, preferable from 2 to 8, particularly preferably 2, of carbon atoms, (ii) a (meth)acrylamide or a (meth)acrylamide optionally substituted by mono- or di-alkyl groups having from 1 to 18 carbon atoms on an N atoms, (iii) a vinyl compound substituted by a heterocyclic group having an N atoms as the member of the heterocyclic ring, and (iv) a N,N-diallylalkylamine and a quaternary ammonium salt thereof. Among them, the (meth)acrylate of the aliphatic alcohol having an amino group or a quaternary ammonium group of (i) is preferable as the monomer having a basic polar group.
Examples of the (meth)acrylate of the aliphatic alcohol having the amino group the quaternary ammonium group shown of (i) include dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl acrylate, diethylaminoethyl methacrylate, quaternary ammonium salts of the foregoing four compounds, 3-dimethylaminophenyl acrylate and a 2-hydroxy-3-methacryl oxypropyltrimetylammonium salt.
Examples of the (meth)acrylamide or the (meth)acrylamide optionally substituted by mono- or di-alkyl groups of (ii) include acryl amide, N-butylacrylamide, N,N-dibutyacrylamide, piperidylacrylamide, methacrylamide, N-butylmethacrylamide, N,N-dimethylacrylamide and N-octadecylacrylamide.
Examples of the vinyl compound substituted by a heterocyclic group having an N atom as the member of the heterocyclic ring of (iii) include vinylpyridine, vinylpyrrolidone, vinyl-N-methylpyridinium chloride and vinyl-N-ethylpyridinium chloride.
Examples of the N,N-diallylalkylamine of (iv) include N,N-diallylmethylammonium chloride and N,N-diallylethyl-ammonium chloride.
Polymerization Initiator
A water-soluble radical polymerization initiator is optionally usable in the invention. Examples of such the initiator include a persulfate such as potassium persulfate and ammonium persulfate, an azo compound such as 4,4′-azobis4-cyanovalerianic acid and its salt, and a salt of 2,2′-azobis(2-amidinopropane) and a peroxide compound. The foregoing radical polymerization initiators may be used as redox type initiators in combination with a reducing agent. The use of the redox initiator is preferable since the polymerization activity is enhanced, the polymerization temperature can be lowered and the polymerization time can be shortened.
Although any temperature may be selected for the polymerization temperature as long as the temperature is more than the lowest radical generating temperature, a temperature within the range of from 50° C. to 90° C. is suitably applied. The polymerization can be carried out at an ordinary temperature or more by the use of a polymerization initiator capable of initiating the polymerization at an ordinary temperature such as the combination of hydrogen peroxide and a reducing agent such as ascorbic acid.
Chain-Transfer Agent: a Compound having a Mercapto Group
A known chain-transfer agent may be used for controlling the molecular weight. Although, there is no limitation on the chain-transfer agent, a compound having a mercapto group is particularly preferred since the toner having a sharp molecular weight distribution and excellent storage ability, fixing strength and anti-offset ability can be obtained by the use of such the compound. Examples of the compound include octylmercaptane, dodecylmercaptane and tert-dodecilmercaptane. For example, ethyl thioglycolate, butyl thioglycolate, t-butyl thioglycolate, 2-ethylhexyl thioglycolate, octyl thioglycolate, decyl thioglycolate, dodecyl thioglycolate, thioglycolic acid ester of ethylene glycol, thioglycolic acid ester of neopentyl glycol, thioglycolic acid ester of pentaerythritol are preferred. Among them, an ester of n-octyl-3-mercaptopropionic acid is particularly preferable.
Surfactant
When the mini-emulsion polymerization is performed using the foregoing polymerizable monomer, it is preferable that the monomer is dispersed as an oil droplet in the aqueous medium using a surfactant. The following ionic surfactants can be cited as examples of suitable compound even though there is no limitation on the surfactant.
Examples of the ionic surfactant include a sulfonic acid salt such sodium dodecylbenzenesulfonate, sodium arylalkylethersulfonate, sodium 3,3-disulfonediphenylurea-4,4-diazo-bis-amino-8-naphtholsulfonate and sodium 2,2,5,5-tetramethyl-triphenylmethane-4,4-diazo-bis-β-naphthol-6-sulfonate; a salt of sulfuric acid ester such as sodium dodecylsulfate, sodium tetradecylsulfate, sodium pentadecylsulfate and sodium octylsulfate; and a fatty acid salt such as sodium oleate, sodium laurate, sodium caprate, sodium caprylate, potassium stearate and potassium oleate.
A nonionic surfactant is also usable. Concrete examples include poly(ethylene oxide), poly(propylene oxide), a combination of poly(propylene oxide) and poly(ethylene oxide), an ester of a higher fatty acid and poly(ethylene glycol), an ester of a higher fatty acid and poly(propylene glycol) and a solbitol ester.
Although these surfactants are principally used in the invention as an emulsifier, the surfactants may be used for another process or another object.
Molecular Weight Distribution of the Resin Particle and the Toner
In the invention, the molecular weight distribution of the toner preferably has a peak or shoulder within the range of from 100,000 to 1,000,000. It is further preferable that the molecular weight distribution has the peaks or the shoulders within the ranges of from 100,000 to 1,000,000, from 25,000 to 50,000 and from 1,000 to 50,000.
A resin is preferred which contains at least a high molecular weight component having the peak or the shoulder within the range of from 100,000 to 1,000,000 and a low molecular weight component having the peak or the shoulder within the range of from 1,000 to less than 50,000. It is further preferable to add an intermediate molecular weight resin having the peak or the shoulder within the range of from 15,000 to 100,000.
The measurement by gel permeation chromatography (GPC) using tetrahydrofuran (THF) as the solvent is suitable for measuring the molecular weight of the toner or the resin. The measuring is carried out according to the following procedure. To a sample to be measured in an amount of from 0.5 to 5 mg, concretely 1 mg, 1.0 ml of THF and sufficiently dissolved by stirring by a stirrer such as a magnetic stirrer at an ordinary temperature. The solution is injected into the GPC apparatus after treatment by a membrane filter with a pore size of from 0.45 to 0.50 μm. The GPC is stabilized at 40° C., then THF is flowed in a rate of 1.0 ml per minute and 100 μl of the sample with a concentration of 1 mg/ml is injected for measuring. As the column, a combination of polystyrene gel columns available in the market is preferably used. Examples of the combination include a combination of Shodex GPC KF-801, 802, 803, 804, 805, 806 and 807, manufactured by Showa Denko Co., Ltd., and a combination of TSKgel G-1000H, G-2000H, G-3000H, G-4000H, G-5000H, G-6000H, G-7000H and TSK guard column, manufactured by Toso Co., Ltd. A refractive index detector (IR detector) or a UV detector is suitably used as the detector. In the measurement of the molecular weight, the molecular weight distribution of the sampled is calculated using a calibration curve prepared by using a monodisperse polystyrene standard particle. About 10 kinds of the standard polystyrene particle are suitably used for preparing the calibration curve.
Coagulant
A coagulant preferably used in the invention is selected from metal salts.
Examples of the metal salt include a salt of a mono-valent metal such as sodium, potassium and lithium; a di-valent metal such as an alkali-earth metal, for example, calcium and magnesium, and a di-valent salt of manganese and copper; and a tri-valent metal such as iron and aluminum.
Concrete examples of the mono-valent metal salt include sodium chloride, potassium chloride and lithium chloride; that of the di-valent metal salt include calcium chloride, zinc chloride, cupric sulfate, magnesium sulfate and manganese sulfate; and that of the tri-valent metal salt include aluminum chloride and ferric chloride. These salts may be optionally selected according to the purpose. Generally, the critical coagulation concentration (coagulation value or coagulation point) is of the di-valent metal salt is smaller than that of the mono-valent metal salt, that of the tri-valent metal salt is further small.
In the invention, the critical coagulation concentration is an index of the stability of the dispersion in the aqueous dispersion liquid, and shows the concentration at which the coagulation is occurred. The critical coagulation concentration is varied depending on the property of the latex itself and the dispersing agent. The critical coagulation concentration is described in S. Okamura, “Kobunsi Kagaku” 17, 601 (1960), and the value of the critical coagulation concentration can be known by the description of that. In another way, the salt to be measured is added into the particle dispersion in various concentrations and the ξ-potential of the dispersion is measured. The critical coagulation concentration of the salt can be decided according to the salt concentration at which the ξ-potential of the dispersion begins to vary.
In the invention, the polymer particle dispersion is treated using the metal salt so that the concentration of the metal salt is exceeded to the critical coagulation concentration. At this time, it is optionally selected according to the purpose that the metal salt is added directly or in a form of an aqueous solution. When the aqueous solution is used, it is necessary that the concentration of the salt in the dispersion is made so as to be larger than the critical coagulation concentration of the polymer particles.
The concentration of the metal salt as the coagulant in the invention is added to the dispersion so that the concentration thereof is become larger than the critical coagulation concentration, preferably 1.2 times or more, more preferably 1.5 times or more, of the critical coagulation concentration.
Colorant
The toner according to the invention is obtained by the salting-out/fusion-adhering of the combined resin particles with the colorant particles.
Various inorganic pigments, organic pigments and dyes can be used as the colorant (the colorant particle to be subjected to the salting-out/fusion-adhering treatment with the combined resin particle) constituting the toner according to the invention. Known inorganic pigments can be used. Concrete examples are described below.
For example, a carbon black such as furnace black, channel black, acetylene black, thermal black and lump black, and a magnetic powder such as magnetite and ferrite are usable as the black pigment.
These pigments may be used singly or in combination according to the requirement. The adding amount of the pigment is from 2 to 20%, preferably from 3 to 15%, by weight of the polymer.
The foregoing magnetite may be added when the toner is used as a magnetic toner. In such the case, it is preferable that the adding amount is from 20 to 60% by weight for giving the sufficient magnetic property.
Known organic pigment and dyes can be used. Concrete examples of the organic pigment and dye are shown below.
Examples of usable magenta or red pigment are as follows: C.I. Pigment Red 2, C.I. Pigment Red 3, C.I. Pigment Red 5, C.I. Pigment Red 6, C.I. Pigment Red 7, C.I. Pigment Red 15, C.I. Pigment Red 16, C.I. Pigment Red 48:1, C.I. Pigment Red 53:1, C.I. Pigment Red 57:1, C.I. Pigment Red 122, C.I. Pigment Red 123, C.I. Pigment Red 139, C.I. Pigment Red 144, C.I. Pigment Red 149, C.I. Pigment Red 166, C.I. Pigment Red 177, C.I. Pigment Red 178 and C.I. Pigment Red 222.
Examples of usable orange or yellow pigment are as follows: C.I. Pigment Orange 31, C.I. Pigment Orange 43, C.I. Pigment Yellow 12, C.I. Pigment Yellow 13, Pigment Yellow 14, Pigment Yellow 15, Pigment Yellow 17, Pigment Yellow 93, Pigment Yellow 94, Pigment Yellow 138, Pigment Yellow180, Pigment Yellow 185, Pigment Yellow 155 and Pigment Yellow156.
Examples of usable green or blue pigment are as follows: C.I. Pigment Blue 15, C.I. Pigment Blue 15:2, C.I. Pigment Blue 15:3, C.I. Pigment Blue 16, C.I. Pigment Blue 60, C.I. Pigment Green 7.
Examples of usable dye are as follows: C.I. Solvent Red 1, 49, 52, 58, 63, 111 and 122, C.I. Solvent Yellow 19, 44, 77, 79, 81, 82, 93, 98, 103, 104, 112 and 162, and C.I. Solvent Blue 25, 36, 60, 70, 93 and 95. A mixture of these may be used.
The foregoing pigments and the dyes may be used singly or in combination according to necessity. The adding amount of the pigment is from 2 to 20%, preferably from 3 to 15%, by weight of the polymer.
The colorant constituting the toner according to the invention may be subjected to a surface modification. Known surface modifying agents can be used. In concrete, a silane coupling agent, a titanium coupling agent and an aluminum coupling agent are preferably used. Examples of the silane coupling agent include an alkoxysilane such as methyltrimethoxysilane, phenyltrimethoxysilane, methylphenyldimethoxysilane and diphenyldimethoxysilane; a siloxane such as hexamethyldisiloxane; γ-chloropropyltrimethoxysilane, vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyl-trimethoxysilane, γ-glycidoxypropyl-trimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane and γ-ureidopropyl-triethoxysilane. Examples of the titanium coupling agent include TTS, 9S, 38S, 41B, 46B, 55, 138S and 238S each manufactured by Ajinomoto Co., Ltd. and sold in the marked with the trade name of Plenact, and A-1, B-1, TOT, TST, TAA, TAT, TLA, TOG, TBSTA, A-10, TBT, B-2, B-4, B-7, B-10, TBSTA-400, TTS TOA-30, TSDMA, TTAB and TTOP each manufactured by Nohon Soda Co., Ltd., and are available in the market. Examples of the aluminum coupling agent include Plenact AL-M manufactured by Ajinomoto Co., Ltd.
The adding amount of the surface modification agent is within the range of from 0.01 to 20%, preferably from 0.1 to 5%, of the colorant by weight.
The surface modification of the colorant particle can be performed by adding the surface modifying agent into the dispersion of the colorant particle and heating the system.
The surface modified colorant particles are took out by filtration and repeatedly subjected to washing by the same solvent and filtration. Then the colorant particles are dried.
Mold Releasing Agent
The toner to be used in the invention is preferably one produced by fusion-adhering the resin particles including a mold releasing agent in the aqueous medium. The toner in which the mold releasing agent is finely dispersed can be produced by salting-out/fusion-adhering the resin particles including a mold releasing agent with the colorant particles in the aqueous medium.
Low molecular weight polypropylene having a number average molecular weight of from 1,500 to 9,000 and low molecular weight polyethylene are preferably used as the mold releasing agent in the toner to be used in the invention. An ester compound represented by the following formula is particularly preferred.
R 1 —(OCO—R 2 ) n
In the formula, n is an integer of from 1 to 4, preferably from 2 to 4, more preferably from 3 to 4, particularly preferably 4; R 1 and R 2 are each a carbon hydride group which may have a substituent. R 1 is a group having from 1 to 40, preferably from 1 to 20, more preferably from 2 to 5, carbon atoms. R 2 is a group having from 1 to 40, preferably from 16 to 30, more preferably from 18 to 26, carbon atoms.
Typical examples of the compound are shown below.
The adding amount of the above compound is from 1 to 30%, preferably from 2 to 20%, more preferably from 3 to 15%, by weight of the whole toner.
It is preferred in the toner of the invention that the mold releasing agent is included in the resin particles by the mini-emulsion polymerization method and then the resin particles are salted out/fusion-adhered together with the colorant particles to form the toner particle.
Charge Controlling Agent
Materials capable of giving various functions to the toner may be added to the toner other than the colorant and the mold releasing agent. Concretely, a charge controlling agent can be used. These materials can be added by various methods such as the method by which the material is added together with the resin particles and the colorant particles at the salting-out/fusion-adhering process to be included in the toner and the method by which the material is added into the resin particle itself.
Various known charge controlling agents capable of being dispersed in water can be used. In concrete, for example, a nigrosine dye, a metal salt of naphthenic acid or a higher fatty acid, an alkoxylized amine, a quaternary ammonium chloride, an azo metal complex and a metal salt of salicylic acid or its metal complex are usable.
External Additive
An external additive may be added to the toner according to the invention for the purpose of improving the fluidity and the cleaning ability. Various kinds of inorganic particle, organic particle and lubricant may be used without any limitation.
Known inorganic particle can be used as the external additive. Fine particles of silica, titania and alumina are preferably usable. These inorganic particles are preferably hydrophilic ones.
Concrete examples of the silica fine particle include R-976, R-974, R-972, R-812 and R-809 each manufactured by Nihon Aerogel Co., Ltd., HVK-2150 and H-200, each manufactured by Hoechst Co., Ltd., and TS-720, TS-530, TS-610, H-5 and MS-5, each manufactured by Cabot Co., Ltd. They are all commercial products.
Concrete examples of the titania fine particle include MT-100S, MT-100B, MT-500BS, MT-600, MT-600SS and JA-1, each manufactured by Teika Co,. Ltd., and TA-300SI, TA-500, TAF-130, TAF-510 and TAF-510T, each manufactured by Fuji Titan Co., Ltd., and IT-S, IT-OA, IT-OB and IT-OC, each manufactured by Idemitsu Kosan Co., Ltd. They are all commercial products.
Concrete examples of the alumina fine particle include RFY-C and C-604, manufactured by Nihon Aerogel Co., Ltd., and TTO-55, manufactured by Ishihara Sangyo Co., Ltd. They are commercial products.
An organic particle having a sphere shape and a number average primary particle diameter of approximately from 10 to 200 nm can be used as the external additive. The material of such the particle is, for example, polystyrene, poly(methyl mthacrylate) or a styrene-methyl methacrylate copolymer.
A metal salt of a higher fatty acid can be used as the external additive. Concrete examples of such the metal salt of higher fatty acid include a metal stearate such as zinc stearate, aluminum stearate, cupric stearate, magnesium stearate and calcium stearate; a metal oleate such as zinc oleate, manganese oleate, ferric oleate, cupric oleate and magnesium oleate; a palmitate such as zinc palmitate, cupric zinc palmitate, magnesium palmitate and calcium palmitate; a linolate such as zinc linolate and calcium linolate; and a ricynolate such as zinc ricynolate and calcium ricynolate.
The adding amount of the external additive is preferably from 0.1 to 5% by weight of the toner.
External Additive Adding Process
The process is a process for adding the external additive to the toner particles.
Various know mixing apparatus such as a tabular mixer, a Henschel mixer, a Nauter mixer and a V-type mixer are usable for adding the external additive to the toner.
Toner Particle
The particle diameter of the toner of the invention is preferably from 3 to 10 μm, more preferably from 3 to 8 μm. The particle diameter can be controlled by the control of the concentration of the coagulant, the adding amount of the organic solvent, the time for fusion-adhering and the composition of the polymer in the course of the production.
When the number average particle diameter is within the range of from 3 to 10 μm, the transfer ability of the toner particles is raised so that the image quality of the half tone, fine line and dot is improved and the fine particle is reduced which has a high adhering force and causes the offset by scattering and adhering to the heating member in the fixing process.
The number average diameter of the toner can be measured by Coulter Counter TA-II, Coulter Multisizer or a laser diffraction particle size measuring apparatus SLAD1100 manufactured by Shimazu Seisakusho Co., Ltd.
In the invention, Coulter Multisizer connected to a personal computer through an interface, manufactured by Nikkaki Co., Ltd., for outputting the particle size distribution. The volume distribution of the toner having a diameter of not less than 2 μm by Coulter Multisizer using an aperture of 100 μm and the particle size distribution and the average diameter are calculated.
Preferable Range of Shape Coefficient of Toner
In the toner according to the invention, the particle having a shape coefficient of from 1.0 to 1.6 accounts for not less than 65% in number. It is preferable that the particle having from 1.2 to 1.6 accounts for not less than 65%, particularly not less than 70%, in number. The shape coefficient toner according to the invention is given by the following equation, which shows the sphere degree of the toner particle.
Shape coefficient=((Major diameter/2) 2 ×π)/Projective area
The major diameter is the width of the particle defined by the distance of two parallel lines each tangent to the projected image of the toner particle on a plane so that the distance is become to the largest. The projective area is the area of the projected image of the toner on a plane. In the invention, the shape coefficient is determined by photographing the toner particle by a scanning electron microscope with magnification of 2,000, and analyzing the photograph by Scanning Image Analyzer, manufactured by Nihon Denshi Co., Ltd. One hundred toner particles are subjected to the measurement and the shape coefficient is calculated by the above equation.
It is preferable in the toner of the invention that the sum M of a relative frequency of the toner particles included in the highest frequency class m 1 and a relative frequency of the toner particles included in the next high frequency class m 2 is not less than 70% in a histogram showing a particle diameter distribution in number which is classified into plural classes every 0.23 of natural logarithm ln D graduated on the horizontal axis of the histogram, where D is the diameter of the toner particle in μm.
When the sum M of the relative frequencies m 1 and m 2 is not less than 70%, the scatter of the size distribution of the toner particle is become narrow. Consequently, occurrence of the selective development can be certainly inhibited by the use of such the toner.
In the invention, the foregoing histogram showing the size distribution based on the number is a histogram in which the natural logarithm lnD of the diameter D is classified every 0.23 into plural classes 0 to 0.23, 0.23 to 0.46, 0.46 to 0.69, 0.69 to 0.92, 0.92 to 1.15, 1.15 to 1.38, 1.38 to 1.61, 1.61 to 1.84, 1.84 to 2.07, 2.07 to 2.30, 2.30 to 2.53, 2.53 to 2.76, . . . The histogram is made out by the following procedure: the particle diameter data of the sample measured by Coulter Multisizer under the following condition is transferred to a computer through an I/O unit and the histogram is output by the size distribution analyzing program in the computer.
Measuring Condition
1. Aperture: 100 μm
2. Sample preparation:
A suitable amount of a surfactant is added to an amount of from 50 to 100 ml of an electrolyte solution Isoton R-11, manufactured by Coulter Scientific Japan Co., Ltd., and stirred, and then an amount of from 10 to 20 mg of the sample to be measured is added to the solution. This system is subjected to an ultrasonic dispersion treatment for 1 minute to prepare the sample liquid.
Developer
The toner according to the invention may be used either for a one-component developer or a two-component developer.
The one-component developer includes a non-magnetic developer and a magnetic developer contained a magnetic particle having a diameter of approximately from 0.1 to 0.5 μm in the toner particle. The toner according to the invention can be applied both type of the developers.
The toner according to the invention can be used in the form of two-component developer by mixing with a carrier. In such the case, known materials, for example, a metal such as iron, ferrite, and magnetite, and an alloy of the foregoing metal with another metal such as aluminum and lead can be used as the magnetic particle of the carrier. The ferrite particle is particularly preferred. The magnetic particle having a volume average particle diameter of from 15 to 100 μm, more preferably from 25 to 80 μm, is suitable.
The volume average particle diameter of the carrier particle can be measured typically by a laser diffraction particle size distribution measuring apparatus HEROS having a wet type dispersing device, manufactured by Sympatec Co., Ltd.
A carrier composed of the magnetic particle coated with resin or a resin disperse type carrier in which the magnetic particles are dispersed in resin is preferably used. An olefin resin, a styrene resin, a styrene-acryl resin, a silicone resin, an ester resin or a fluorine-containing polymer resin is usable without any limitation. A styrene-acryl resin, a polyester resin a fluorine-containing resin and a phenol resin are usable for constituting the resin dispersion type carrier without any limitation.
Image Forming Method
First, an example of the image forming apparatus according to the invention is described bellow.
FIG. 2 is a schematic illustration of the image forming apparatus as an example of embodiment of the invention. In the drawing, 4 is a photoreceptor as a typical example of the static latent image forming device relating to the invention. The photoreceptor comprises an aluminum drum substrate and an organic photoconductive layer (OPC) as the photosensitive layer provided on the external surface of the drum substrate. The drum is rotated in the direction of the arrow in a prescribed speed. The external diameter of the photoreceptor 4 is 60 mm in this embodiment.
In FIG. 2, a light beam for exposure is generated from a laser light source 1 according to image information lead by an original image leading device which is not shown in the drawing. The light beam is distributed by a polygon mirror to the perpendicular direction to the drawing paper and irradiated to the photoreceptor surface through an fθ lens for calibrating the distortion of the image to form a static latent image. The photoreceptor is previously charged by a charging device 5 and rotated clockwise synchronized with timing of the image exposure.
The static latent image on the photoreceptor is developed by a developing device 6 . The developed image is transferred onto a recording material 8 conveyed according to adjusted timing by the effect of a transfer device 7 . The recording material 8 is separated from the photoreceptor 4 by a separating device or a separating electrode 9 . The developed toner image is transferred and carried on the recording material and introduced into a fixing device 10 so as to be fixed.
The toner not transferred and remained on the photoreceptor surface is removed by a cleaning blade type cleaning device 11 . After the cleaning, remained charge of the photoreceptor is removed by a precharging light exposure (PCL) 12 . Then the photoreceptor is uniformly charged again by the charging device 5 for next image formation.
Although the recording material is typically a sheet of paper, any material on which the non-fixed developed image can be transferred can be used without any limitation. PET base for OHP is usable of course.
A rubber-like material having a thickness of approximately from 1 to 30 mm is used as cleaning blade 13 . Urethane rubber is usually used as the material of the blade. The cleaning blade is preferably released from the photoreceptor when the image forming operation is not performed since the blade is contacted to the photoreceptor and tends to conduct heat.
Recently, a image forming method using a digital system is actively investigated in the field of the electrophotography in which a latent image is formed on the photoreceptor and developed to form a visible image, since the quality improvement, conversion and edition of image can be easily performed and a high quality image can be obtained by the digital image forming system.
As the optical scanning system in which light is modulated by a digital image signal from a computer or an original picture to be copied, (1) an apparatus in which a sonic optical modulator is inserted in the laser optical system and light is modulated by the modulator, and (2) an apparatus using a laser for directly modulating the laser light, are used. The charged photoreceptor is exposed to a light spot irradiated from such the scanning optical system to form a dot image.
The light beam irradiated from the scanning optical system has a spherical or elliptical luminance distribution like a normal distribution with an extended foot. In the case of laser beam, the shape of the light spot is very small sphere or ellipse having a diameter in the main scanning or sub-scanning or both directions of, for example, from 20 to 100 μm.
The image forming apparatus may be constituted so that a processing cartridge is installed therein, which contains at least one of the photoreceptor 4 , the charging device 5 , the developing device 6 , the cleaning device 11 and the transfer device 7 .
The toner according to the invention is suitably applied an image forming apparatus having a fixing process for fixing the recording material carrying the toner image is passed between a heating roller and a pressure roller constituting the fixing device.
FIG. 3 shows a cross section of an example of the fixing device to be used in the image forming apparatus using the toner according to the invention. The fixing device shown in FIG. 3 has a heating roller 80 and a pressure roller 70 contacting with the heating roller. In FIG. 3, T is a toner image formed on a recording material or an image support 8 .
The heating roller 80 is composed of a metal core 81 and a covering layer 82 comprising a fluorinated resin or an elastic material and covering the surface of the metal core, and a heating member 75 composed of a line heater is included in side of the metal core.
The metal core 81 is composed of a metal and the external diameter thereof is from 10 to 70 mm. The metal of the metal core 81 is not specifically limited, and examples of suitably usable metal include iron, aluminum and copper, and an alloy thereof.
The thickness of the metal core 81 is from 0.1 to 15 mm which is decided on the balance of the requirement energy saving (reducing the thickness) and the strength depending on the material of the metal core. For example, an aluminum metal core with a thickness of 0.8 mm is necessary to hold the strength of an iron metal core with a thickness of 0.57 mm.
Example of the fluorinated resin for forming the surface layer 71 of the covering layer 82 include polytetrafluoroethylene (PTFE) and tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer.
The thickness of fluorinated resin surface layer 71 is from 10 to 150 μm, preferably from 20 to 400 μm.
When the thickness of the surface layer 71 of the covering layer is less than 10 μm, the ability of the surface layer cannot be sufficiently displayed, and the durability of the fixing cannot be maintained. Besides, when the thickness exceeds 500 μm, the surface thereof tends to be scratched by paper powder and the toner adhered on the scratch causes a contamination of the image.
As the elastic material constituting the covering layer 82 , a silicone rubber having a high heat resistively such as LTV, RTV and HTV and a silicone rubber sponge are preferably usable.
The Ascar hardness of the elastic material constituting the cover layer 82 is less than 80°, preferably less than 60°.
The thickness of the covering layer 82 composed of the elastic material is from 0.1 to 30 mm, preferably from 0.1 to 20 mm.
When the Ascar hardness of the elastic material of the covering layer 82 exceeds 80° or the thickness of the covering layer 82 is less than 0.1 mm, the effect of the soft fixing such as improvement of the color reproducibility by the toner layer having a smoothed interface cannot be obtained since the nip of the rollers of the fixing device cannot be made wide.
A halogen heater is suitably used as the heating member 57 . The pressure roller comprises the metal core 83 and the covering layer 83 of the elastic material provided on the metal core. There is no limitation on the elastic material constituting the covering layer 84 and, for example, various kinds of soft rubber and rubber sponge are usable. The silicone rubber and silicone rubber sponge described as the examples of material for the covering layer 82 are preferably used.
The Ascar hardness of the elastic material constituting the cover layer 84 is less than 80°, preferably less than 70°, more preferably less than 60°.
The thickness of the covering layer 84 is from 0.1 to 30 mm, preferably from 0.1 to 20 mm.
When the Ascar hardness of the elastic material of the covering layer 84 exceeds 80° or the thickness of the covering layer 84 is less than 0.1 mm, the effect of the soft fixing cannot be obtained since the nip of the rollers of the fixing device cannot be made wide.
The metal of the metal core 83 is not specifically limited, and examples of the metal include iron, aluminum and copper, and an alloy thereof.
The contacting load or total load between the heating roll 80 and the pressure roller 70 is usually from 40 N to 350 N, preferably from 50 to 300 N, more preferably from 50 to 250 N. The contacting load is decided considering the strength, namely the thickness of the metal core 81 , of the heating roller 80 . For example, a load less than 250 N is preferable as to the heating roll having an iron metal core of 0.3 mm.
The nip width is preferable from 4 to 10 mm and the face pressure at the nip is preferably from 0.6×10 5 to 1.5×10 5 Pa from the viewpoint of the anti-offset ability and the fixing ability.
In an example of the fixing condition of the fixing device shown in FIG. 3, the fixing temperature or the surface temperature of the heating roller 80 is from 150 to 210° C. and the line speed of fixing is from 80 to 640 mm/sec.
A cleaning mechanism may be added to the fixing device used in the invention when it is necessary. In such the case, a method by which silicone oil is supplied by a pad, a roller or a web each immersed with the silicone oil may be sued for supplying the silicone oil to the upper roller or heating roller of the fixing device.
Silicone oil with a high heat resistively such as polydimethylsilicone, polyphenylmethyl silicone and polydimethylsilicone is used. Silicone oil having a viscosity of from 1 to 100 Pa·s is suitably used since one having a low viscosity is excessively flow out at the supplying time.
The effect of the invention is considerably enhanced when the image forming process includes a process using the fixing device in which no or extremely small amount of silicone oil is supplied. Therefore, the supplying amount of the silicone oil is preferably not more than 2 mg per sheet of A4 size paper.
The amount of the silicone oil adhered on the recording paper or the image support is reduced by making the supplying amount of the silicone oil to not more than 2 mg per sheet of A4 size paper. Consequently, a difficulty of writing by an oily ink such as a ball point pen caused by the silicone oil is not occurred and the retouching ability is not degraded.
Moreover, problems such as degradation of the anti-offset ability caused by the deterioration of the silicone oil during a long lapse and contamination of the optical system and the charging electrode by the silicone oil can be avoided.
The supplying amount is calculated by Δw/100 wherein Δw is the different of the weight of the fixing device caused by passing of 100 sheets of the blank A4 size recording paper between the rollers of the fixing device at the prescribed temperature.
EXAMPLES
The invention is concretely described referring examples below. The embodiment of the invention is not limited to the examples.
Preparation of Toner and Developer
1. Preparation of latex
Preparation of Latex 1HLM
1: Preparation of Core Particle (The First Step of Polymerization)
In a 5,000 ml separable flask with a stirrer, a thermal sensor, a cooler and a nitrogen supplying apparatus, a surfactant solution composed of 3,010 g of ion-exchanged water and, dissolved therein, 7.08 g of anionic surfactant A, C 10 H 21 (OCH 2 CH 2 ) 2 OSO 3 Na, was charged as an aqueous medium. The temperature of the content was raise by 80° C. while stirring at 230 rpm under a nitrogen gas stream.
Into the surfactant solution, an initiator solution composed of 9.2 g of polymerization initiator, potassium persulfate KPS, dissolved in 200 g of ion exchanged water and the temperature of the content was adjusted to 75° C. Then a monomer mixture liquid composed of 70.1 g of styrene, 19.9 g of n-butyl acrylate and 10.9 g of acrylic acid was dropped into the solution spending 1 hour. This system was heated and stirred for 2 hours for carrying out polymerization or the first step of polymerization. Thus latex, a dispersion of resin particle comprising a polymer resin, was prepared. The latex was referred to as Latex H.
2: Formation of Interlayer (The Second Step of Polymerization)
In a flask with a stirrer, 72.0 g of Exemplified Compound 19 was added as a mold releasing agent to a monomer mixture liquid composed of a 105.6 g of styrene, 30.0 g of n-butyl acrylate, 6.4 g of acrylic acid and 5.6 g of n-octyl-3-mercaptopropionic acid ester. The content was heated at 80° C. for dissolving the mold releasing agent. Thus Monomer Solution 1 was prepared.
Besides, a surfactant solution composed of 2700 ml of ion exchanged water and, dissolved therein, 1.6 g of the foregoing anionic Surfactant A was heated by 80° C. and 28 g in terms of the solid ingredient of the dispersion of the core particle Latex 1H was added to the surfactant solution. Then the foregoing Monomer Solution 1 was mixed and dispersed into the surfactant solution containing Latex 1H by a mechanical dispersing machine Cleamix having a circulation channel, manufactured by M-Tech Co., Ltd., to prepare an emulsion which contains emulsified particles having a uniform particle size of 284 nm.
Then, an initiator solution composed of 240 ml of ion-exchanged water and, dissolved therein, 5.1 g of the polymerization initiator KPS and 750 ml of ion-exchanged water was added to the emulsion. This system was heated and stirred at 80° C. for 3 hours for carrying out polymerization, the second step of polymerization. Thus latex, a dispersion of a combined resin particle comprising the high molecular weight resin particle covered by an intermediate molecular weight resin was prepared. This latex was referred to as Latex 1HM.
3: Formation of Outer Layer (The Third Step of Polymerization)
To the foregoing Latex 1HM, an initiator solution composed of 200 ml of ion-exchanged water and, dissolved therein, 7.4 g of the polymerization initiator KPS was added and a monomer mixture of 300 g of styrene, 95 g of n-butyl acrylate, 15.3 g of methacrylic acid, and 10.4 g of n-octyl-3-mercaptopropionic acid ester was dropped spending 1 hour under a condition of 80° C.
After the dropping, polymerization, the third step of polymerization was carried out by heating and stirring for 2 hours. Then the reaction liquid was cooled by 27° C. Thus latex, a dispersion of resin particle having the core, inter layer and outer layer, was obtained. The latex was referred to as Latex 1HML.
The combined resin particle of Latex 1HML has peaks of molecular weight distribution at 138,000, 80,000 and 13,000, and the weight average particle diameter of the resin particle was 122 nm.
Preparation of Latex 2HML
Latex 2HML was prepared in the same manner as in Latex 1HML except that an anionic Surfactant B, sodium dodecylsulfonate SDS, was used in place of anionic Surfactant A.
The combined resin particle of Latex 2HML has peaks of molecular weight distribution at 138,000, 80,000 and 12,000, and the weight average particle diameter of the resin particle was 110 nm.
Preparation of Toner
Preparation of Toner Particle
Preparation of Toner 1
In 1,600 ml of ion-exchanged water, 59.0 g of anionic Surfactant A was dissolved by stirring. To the solution, 420.0 g of Carbon black Regal 330, manufactured by Cabot Co., Ltd., was gradually added and dispersed by Clearmix, manufactured by M-Tech Co., Ltd., to prepare a dispersion of the colorant particle. The dispersion of the colorant was referred to as Colorant Dispersion 1. The weight average diameter of the colorant particle in Colorant Dispersion 1 was 98 nm according to the measurement by electrophoresis light scattering photometer ELS-800, manufactured by Ootsuka Denshi Co., Ltd.
In a four mouth flask as the reaction vessel to which a thermal sensor, cooler, nitrogen conduction apparatus and stirrer were attached, 420.7 g in terms of solid component of the foregoing Latex 2HML, 900 g of ion-exchanged water 166 g of Colorant Dispersion 1 were charged and stirred. The content was heated by 30° C. and the pH of the liquid was adjusted to 9.0 by the addition of a sodium hydroxide solution having a concentration of 5 moles/liter.
Then an aqueous solution of 12.1 g of magnesium chloride dissolved in 1,000 ml of ion-exchanged water was added to the foregoing liquid spending 10 minutes while stirring. Thereafter, the liquid was stood for 3 minutes and heated up by 9° C. spending 6 minutes with a temperature raising rate of 10° C./minute.
In that the state, the diameter of the associated particle was measured by Coulter-Counter TA-II, manufactured by Coulter Co., Ltd., and the growing of the particle is stopped at the time at which the number average particle diameter was reached at 5.5 μm by adding a solution of 80.4 g of sodium chloride in 1,000 ml of ion-exchanged water. The system is further stirred at 85° C. for 2 hours to continue the adhesion as a ripening treatment.
Thereafter, the system was cooled by 30° C. at a cooling speed of 8° C./minute, and 20 μl of Perfume 1 and 10 μl of Perfume 2 was added as shown in Table 1. Moreover, pH was adjusted to 2.0 by hydrochloric acid and the stir was stopped. Thus formed associated particles were filtered by a Nutsche funnel and repeatedly washed by ion-exchanged water of 45° C. To the associated particles on the Nutsche funnel, 10 g of the deodorant shown in Table 1 dissolved in 2 kg of ion-exchanged water was poured and filtered. Then the particles were dried by air heated at 40° C. To the dried particles, 0.8 parts by weight of hydrophobic silica and 1.0 pat by weight of hydrophobic titania were added. The mixture was mixed by a Henschel mixer for 25 minutes at a circumference speed of rotating wing of 30 m/sec. Thus Toner 1 was obtained.
Toners 2 through 9 and Comparative Toners 1 through 3 each having the constitution shown in Table 1 were prepared in the similar manner to the preparation of Toner 1.
Deodorant 1: Deodorant of Plant Extract
Deodorant 1 was prepared by dissolving 10 g of deodorant F118, a deodorant of plant extracts, available in the make, manufactured by Fine 2 Co., Ltd., in 2 kg of ion-exchanged water at 40° C.
Deodorant 2: Deodorant Containing Phytontid as Plant Extracts
Deodorant 2 was prepared by dissolving 10 g of Biodash, a deodorant of plant extracts, available in the make, manufactured by Daiso Co., Ltd., in 2 kg of ion-exchanged water at 40° C.
Deodorant 3: Deodorant Containing Catechin and Flavonoid as Plant Extracts
Fifty grams of raw tea leaf was crushed into granule having a particle size of not more than 1 mm. The crushed raw leaf was extracted by 200 ml of 50% ethanol aqueous solution at 60° C. to prepare Extract 1. Extract 1 contained 2% by weight of effective ingredient, 50% by weight of ethanol and 48% by weight of water.
Besides, ethanol Extract 2 was prepared using bean sprouts and unripe apple as plants having a high content of flavonoid. In concrete, 30 g of the bean sprouts and 50 g of the unripe apple were immersed in 100 ml of water to prepare a plant extract. To 100 ml of thus obtained extract, 200 ml of the foregoing Extract 1 was added to prepare ethanol Extract 2 containing catechin and flavonoid. Ethanol Extract 2 contained 6% by weight of effective ingredients, 36% by weight of ethanol and 58% by weight of water. Ethanol Extract 2 was dissolved in 2 kg of ion-exchanged water to prepare a deodorant. Thus obtained deodorant was referred to as Deodorant 3.
Deodorant 4: Enzyme Type Deodorant
Deodorant 4 was prepared by dissolving 5 g of Biodash P·500, a deodorant available in the market, manufactured by Daiso Co., Ltd., in 2 kg of ion-exchanged water at 40° C.
Deodorant 5: Enzyme Type Deodorant Containing Plant Extract
Deodorant 5 was prepared by dissolving 5 g of Bio C, manufactured by Console Cooperation, in 2 kg of ion-exchanged water at 40° C. Bio C is an enzyme type deodorant containing plant extract ingredient and available in the market.
Deodorant 6: Metal Phthalocyanine Type Deodorant
Deodorant 6 was prepared by dissolving 1% by weight octacaroboxyferrophthalocyanine in an aqueous solution of an alkali.
Deodorant 7: Artificial Enzyme Deodorant
A cationic group was introduced in β-cyclodextrin by reaction of a mixture of 10 g of β-cyclodextrin and 25 g of 3-chloro-2-hydroxypropyltrimethylammonium chloride at a pH value of 9.0 and a temperature of 70° C.
Three grams of octacarboxyferrophthalocyanine was dissolved in 100 ml of a 0.1% aqueous solution of sodium hydroxide and the pH of the solution was adjusted to 8.0 by acetic acid. The foregoing β-cyclodextrin, in which the cationic group was introduced, was added to the above solution. The mixture was uniformly mixed and heated by 90° C. and reacted for 60 minutes to obtain the subjective artificial enzyme solution.
Deodorant 7 was prepared by diluting the 100 ml of thus obtained artificial enzyme solution by 2 kg of ion-exchanged water.
Deodorant 8: Microbe Deodorant 1
The following components were mixed and stirred for 24 hours at 30° C.
Ammonium chloride
0.5
g
Glucose
5.0
g
Water
2.5
1
Microbe powder: Bacillus subtilis
5.0
g
The culture medium was subjected to centrifugal separation and the supernatant was referred to as Deodorant 8.
TABLE 1
Toner
Perfume 1
Perfume 2
Deodorant
Example 1
Toner 1
Linalyl
Amylis oil
Deodorant
acetate
2
Example 2
Toner 2
14-Tetrade-
α-Pinene
Deodorant
canolide
1
Example 3
Toner 3
1,8-cineol
3-propyl-
Deodorant
cyclopentade-
3
canone
Example 4
Toner 4
Cyclopentade-
9-hexadecene-
Deodorant
canone
16-olide
4
Example 5
Toner 5
Eugenol
α-terpeneol
Deodorant
6
Example 6
Toner 6
Geranyl
Eucalyptus
Not used
acetate
lemon
Example 7
Toner 7
Gelaniol
Cedrol
Not used
Example 8
Toner 8
Cyclohexade-
Amilis oil
Deodorant
canone
7
Example 9
Toner 9
Cycloheneico-
Amilis oil
Deodorant
sane
5
Comparative
Comparative
Lemon grass
Not used
Not used
example 1
toner 1
oil
Comparative
Comparative
Eugenyl
Decenal
Deodorant
example 2
toner 2
acetate
8
Comparative
Comparative
Not used
Not used
Not used
example 3
toner 3
Preparation of Developer
A developer was prepared by mixing each of the colored toners mixed with the carrier. The concentration of the toner was 6% by weight.
For evaluation, the photoreceptor and each of the developer were charged into the digital copying machine having the image forming process shown in FIG. 2 which has the corona charging device, laser exposing system, reversal developing device, static transfer device, separating claw and cleaning blade.
The conditions of the digital copying machine were set for the evaluation as follows.
Charging condition
Charging device: Scorontron charging device
Initial charging potential: −750 V
Exposure condition
Exposure amount was set so that the potential at the exposed area was become to −50 V.
Developing condition
DC bias: −550 V
Transfer condition
Transfer electrode: Corona discharge electrode
In the fixing device, a heating roller having an iron core and a cover layer of tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer PFA with a thickness of 25 μm and a surface roughness of Ra of 0.8 μm, and a pressure roller having an iron core and a HTV silicone rubber layer covered with a PFA tube with a thickness of 120 μm and a surface roughness of 0.8 μm were provided.
The nip width was 3.8 mm and the line speed was 420 mm/sec. Any cleaning device and silicone oil supplying mechanism were not attached to the fixing device. The fixing temperature was set at 165° C. and controlled according to the surface temperature of the heating roller.
The copying test was performed in a closed room with an area of 19.8 m 2 , and 10 persons were subjected to Kraepelin test while measuring the brain waves in the room.
Brain waves of from 8 to 13 Hz appeared at the back of the head or α-Waves were measured as an indicator of relaxation.
The addition calculation work progression coefficient was evaluated by an average value of the 10 subject persons at 30 minutes after the start of the work.
The Kreapelin test known as a method for measuring the efficiency of the calculating work is called as “Continuous primary adding calculation work”, in which an adding calculation of one-digital numbers is performed.
The calculation work for 15 minutes was performed twice, 30 minutes in total, before and after a rest for 5 minutes. Such the procedure is the most usually applied as the mental work loading test for evaluation the work efficiency.
TABLE 2
Cosθ as to odor
Cosθ as to
Cosθ as to odor of
of n-butyl
odor of
mercaptocaroxylic
acrylate
styrene
acid
Example 1
0.99
0.996
0.997
Example 2
0.992
0.998
0.996
Example 3
0.988
0.994
0.998
Example 4
0.987
0.992
0.995
Example 5
0.993
0.997
0.998
Example 6
0.988
0.991
0.997
Example 7
0.991
0.993
0.994
Example 8
0.987
0.997
0.997
Example 9
0.994
0.996
0.999
Comparative
0.982
0.992
0.989
example 1
Comparative
0.987
0.987
0.992
example 2
Comparative
0.996
0.999
0.981
example 3
TABLE 3
Progression coefficient of
adding calculation
Ratio of subject
according to Kreapelin test
persons
With fragrant
generating α-
according to
Without
waves
the invention
fragrant
Example 1
10 persons in 10
76
61
persons
Example 2
9 persons in 10
71
62
persons
Example 3
9 persons in 10
70
58
persons
Example 4
8 persons in 10
65
59
persons
Example 5
8 persons in 10
66
59
persons
Example 6
9 persons in 10
69
60
persons
Example 7
9 persons in 10
91
62
persons
Example 8
9 persons in 10
70
61
persons
Example 9
9 persons in 10
71
62
persons
Comparative
1 person in 10
61
61
example 1
persons
Comparative
2 persons in 10
62
61
example 2
persons
Comparative
No person
60
64
example 3
The ratio of the subject persons generating the α-waves in Examples 1 through is larger than that in Comparative examples 1 through 3. Therefore it is found that efficiency of the calculation efficiency is raised.
According to the invention, the evaluate and design with precision the smell given off from the image forming apparatus such as the copy machine or the printer, which are become to be frequently used near man, and to make the smell to a pleasant smell for man. The evaluation and the design of the toner is previously carried out from the viewpoint of that the pleasant smell is given off in the image forming process since the major cause of the smell given off from the image forming apparatus is the toner for developing the static latent image. | The present invention relates to a toner for developing a static latent image, wherein a smell of the toner has a cos θ of from 0.990 to 0.998 as to the smell of styrene and a cos θ of from 0.986 to 0.994 as to the smell of n-butyl acrylate in the smell space formed by styrene and n-butyl acrylate, and a toner for developing a static latent image, wherein a smell of the toner has a cos θ of from 0.990 to 0.998 as to the smell of styrene and a cos θ of from 0.991 to 0.999 as to the smell of mercaptocarboxylic acid ester in the smell space formed by styrene and mercaptocarboxylic acid ester. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This is a nationalization of PCT application Ser. No. PCT/GB 2004/050001 filed 16 Aug. 2004 (Int'l Publication No. WO 2005/106185, published 10 Nov. 2005) which claims priority from U.S. Application 60/567,235 filed 1 May 2004—both of which applications are incorporated fully herein for all purposes and from both of which the present invention and application claim priority under the Patent Laws.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an apparatus and method for facilitating handling pipe and handling pipe strings particularly, but not exclusively, to an elevator for handling pipe on drilling rigs. The pipe may be a single section, stand or string of drill pipe, a single section, stand or string of casing, tubular, premium tubular, drill collars or pipe incorporating a well tool.
2. Description of Related Art
In the drilling, completion and work over of a borehole in the oil, gas, water and geothermal industries pipes are run into and out of a borehole. Such an operation is sometimes referred to as “tripping in” for moving pipes down into a borehole and “tripping out” for moving pipes up and out of a borehole. Each of these operations requires pipes to be moved around a drilling rig. Accordingly, there are many problems associated with the handling and logistics of pipe handling of a drilling rig especially in the interconnecting, disconnecting, and storing of pipes on an oil drilling platform without interrupting the drilling process.
The types of pipes which need to be moved around a drilling rig comprise drill pipes, drill collars, casings, tubing, perforated tubing, liners, liner hanger tools, packers, well cleaning tools etc.
During a drilling operation on a conventional oil drilling platform, when the drill bit has penetrated such a distance into a borehole that only a small part of the drill string extends upwards from the upper surface of the drill floor, the drilling operation is stopped, and a new tubular drill string section is moved from a storage site or rack positioned outside the drill floor and connected to the upper end of the drill string. Once the new section is connected, the drilling operation may be continued. Normally, the length of the drill string sections is 30 feet or about 9 m (or a double or triple multiple thereof). Each time the drill bit has penetrated further into the underground, the drilling operation is usually stopped and a further drill string section (or stand) is added.
Many prior art drilling systems have a rotary drive, and/or a top drive, a supportive rig floor, a derrick extending vertically above said rig floor, and a travelling block which can be raised and lowered within the derrick. During drilling operations, such rig equipment is often used to insert and, in some cases remove, tubular goods from a well. Drill bits and/or other equipment are frequently lowered into a well and manipulated within a tubular drill pipe. Once a well has been drilled to a desired depth, large diameter pipe called casing is often installed in the wellbore and cemented in place in order to provide structural integrity to the well and to isolate down hole formations from one another.
Current systems for moving pipes on and around a drilling rig incorporate an elevator arranged on the end of a line hanging over a pulley wheel or travelling block hung from a derrick of the drilling rig or from bails of a top drive. The other end of the line is wound round a winch. The elevator generally comprises a pair of hinged semicircular segments, a latch and a safety mechanism to ensure the latch is closed properly. Such an elevator is sold by BJVarco under the trade name “BX Elevator”(™).
The pipe lies horizontally on a “catwalk” or on an inclined ramp or conveyor and is lifted manually clear of the surface on which it lies or the end of the pipe is exposed over a ledge. The segments of the elevator are closed about the body of the drill pipe and the latch is closed and the safety mechanism, usually a split pin is pushed into position to ensure the latch is properly closed and will not allow the latch to be opened until the split pin is removed. The elevator loosely fits around the body of the pipe such that the elevator can slide there along until the elevator abuts an upset in the pipe or a collar threaded to an end of the pipe. Drill pipe comprises an upset known as a “box” in which a female threaded end is located, alternatively an end of the pipe is threaded on to which is threaded a collar of larger outer diameter, which form a shoulder. The winch is activated to lift the elevator and the pipe hanging there from clear of the rig floor to facilitate movement of the pipe on and around the drilling rig. A roughneck is then able to swing the pipe to another location, usually for stabbing into a string of pipe already in the well or located in a mouse hole. One particular use is to facilitate movement of the drill pipe from the pipe storage areas to the well centre and the storage area close to the well centre known as the “fingerboard”. This method is used in tripping-in operations. The elevator is then used to hold the entire weight of the pipe string whilst the slips in the platform, known as a spider, are released. The pipe string is rotated and lowered into the well and then the slips in the spider are engaged with the pipe and the elevator released.
The BJ Varco “BX hydraulically actuated elevator” is able to orient the throat of the elevator between a position to engage a vertical pipe to a position to engage a horizontal pipe and engaging a pipe lying at any angle therebetween. The elevator comprises segment in the form of hinged doors. The doors on a large elevator, which must be closed around the pipe, may weigh several hundred pounds. An elevator with doors needs clearance for the doors to swing in an arc under the pipe being engaged. The pipe has to be elevated, or clearance otherwise provided, for swinging doors.
Many prior art elevators are of a “non-slip” variety. The non-slip variety are especially suited to handle pipe which does not have an upset, although may also be used with pipes which have upsets. These pipes are known as “flush”, “near flush” or “smooth walled” pipes. The non-slip elevator is provided with jaws with non-slip teeth move into engagement with the pipe, which prevents the pipe from slipping. Thus smooth walled pipe may be moved with such an elevator. The non-slip elevators have generally been constructed with doors (generally, one or two) which open to allow the insertion or removal of the pipe; doors which traditionally are heavy, slow in operation, difficult to handle and can present a considerable safety hazard to the operator. The balance point of such an elevator can change when the doors are open, thus creating handling problems and adding danger to the operator. Especially with very heavy pipes, for example, large casing, the pipe is initially in a horizontal position, laying in place on or near the floor beneath a derrick, and the hinged door elevator is lowered near the point of attachment to the pipe. The derrick personnel then are required to open the heavy door or doors, which may weigh several hundred pounds, to allow the elevator to be placed over the tubular. Because the door or doors must close around the tubular, the tubular end around which the elevator is located is often above the derrick floor.
Often there is idle time in which no actual drilling takes place. In view of the fact that the investment made in a drilling rig is very high even a relatively small reduction of the idle time is significant.
One solution commonly used to reduce the idle time on drilling rigs is to assemble two drill pipe sections, known as “singles”, each having a length of about 10 m into a 20 m stand, known as a “double”, placing the singles in a mouse hole adjacent to the drilling opening and connecting the singles by using air tuggers and spinning wrenches while the drilling operations proceeds.
One exemplary system and apparatus for such offline stand building is described in U.S. Pat. No. 4,850,439, the disclosure of which is incorporated herein by reference. However, although these conventional offline stand building systems do create significant efficiencies in the drilling process, they generally utilize many complex pieces of equipment, such as, hoists and multi-purpose pipe handling machines that result in a system which is complicated, costly, and requires significant ongoing maintenance.
Tubulars such as casing, drill pipe or other pipe are typically installed in a number of sections of roughly equal length. These pipe sections are typically installed one at a time, and screwed together or otherwise joined end-to-end to make a continuous length of pipe. In order to start the process of inserting pipe in a well, a first joint of pipe is lowered into the wellbore at the rig floor, and suspended in place using a set of “lower slips”. Such lower slips are often wedge-shaped dies which can be inserted between the outer surface of said pie and the bowl-like inner profile of the rotary table. Such lower slips hold the weight of the pipe and suspend the pipe in the well. Although such lower slips can be automated, in many applications such lower slips are manually inserted and removed by rig personnel.
To install pipe into a well, a first joint of pipe is generally inserted into a well and positioned so that the top of said joint of pipe is located a few feet above the rig floor. A rig crew or a pipe handling machine grabs a second joint of pipe, lifts the second joint of pipe vertically into the derrick, positions the second joint above the first joint which was previously run into the well, and “stabs” a male threaded end, known as a “pin-end” at the bottom of said second joint into a female threaded end known as a “box-end” at the top of the first joint. The second joint is then rotated in order to mate the threaded connections of the two joints together. Then an elevator attached to the travelling block in the rig derrick is typically lowered over the top of the second (i.e., upper) joint of pipe. Such elevators have a central bore which is aligned with the uppermost end of the joint of pipe. The pipe is received within the central bore of the elevator. Once the elevator has been lowered over the pipe a desired distance, slips within such elevators can be activated to latch or grip around the outer surface of said joint pipe. Depending on the length of the second joint of pipe, this can often occur 12 m (40 feet) or more above the rig floor.
Upon proper latching and engagement of the elevator slips around the body of the pipe, the travelling block and elevator is raised to take weight off of the lower slips. The lower slips can then be removed. Once the lower slips are removed, the entire weight of the pipe string is suspended from the elevator slips. The pipe can then be lowered into the well by lowering the traveling block. After the second or upper joint of pipe is lowered a sufficient distance into the well, the lower slips are again inserted in place near the rig floor.
The process is repeated until the desired length of pipe (i.e., the desired number of joints of pipes) is inserted into the wellbore. This same process can be utilized for many different types and sizes of pipe whether small diameter drill pipe or large diameter casing. The entire weight of the pipe can be held or suspended by the elevators and by the elevator slips. This pipe can be very heavy, especially when many joints of large diameter and/or heavy-wall casing are being run into a well.
Accordingly, it is important that the elevator slips be properly latched around the uppermost section of pipe in the derrick to ensure that the pipe remains securely positioned within the elevators. If the pipe is not properly secured within the elevators, it is possible that the pipe drop or fall out of the elevators, causing damage to the rig or the well, or injury to rig personnel. Incorporated fully herein by reference are U.S. Pat. Nos. 6,626,238 B2; 6,073,699; 5,909,768; 5,84,647; 5,791,410; 4,676,312; 4,604,724; 4,269,554; 3,882,377; 6,494,273; 6,568,479; 6,536,520 B1; and 6,679,333 B2.
U.S. Pat. No. 6,073,699 discloses an elevator for lifting wellbore tubulars, the elevator having a pair of hinged doors, the doors interlocking with the use of a locking pin to prevent the elevator from opening.
BRIEF SUMMARY OF THE INVENTION
The inventors have recognized that it is advantageous to have a remotely operated slip type elevator; that hydraulic circuits are very controllable and reliable; that the elevator has to work with top drive systems; to be able to handle flush and near flush pipe safely; for a single elevator which, by replacing the slips with one of six sets of sips can handle pipes which range between 2⅜″-2⅞″ for the first size set of slips, 2⅞″-3½″ for the second size set of slips, 3½″-4½″ for the third size set of slips, 4½″-5½″ for the fourth size set of slips, 5⅝″-6⅝″ for the fifth size set of slips and 6⅝″-7⅝″ for the sixth size set of slips.
According to the present invention, there is provided an apparatus for handling pipes, the apparatus comprising a body having a tapered surface and at least a first slip and a second slip slidable on the tapered surface, the apparatus further comprising a slip actuator for setting the at least first slip and the second slip characterized in that the first slip and the second slip have interengaging elements therebetween such that upon actuation of the slip actuator, the first slip is set and the second slip is set by the interengaging elements transferring the setting force from the slip actuator through the first slip to the second slip.
A slip is any item which can be used to prevent or inhibit a pipe from falling through an aperture, such as the throat of an elevator. A slip is traditionally a wedge inserted between an outer body provided with a tapering surface and the outer wall of a pipe.
Traditionally the slip tapers, although a tapering outer surface is not essential, any arms or feet which provide a tapered interface would suffice. The taper allows easy removal of the slip, which would otherwise be very difficult. The taper allows the pipe engaging surface to move radially away from the pipe, as the pipe engaging surface is designed to resist longitudinal movement, mainly to inhibit downward slippage of a pipe or string of pipe, but also to inhibit a small amount of upward force. The slip may have a substantially planar pipe engaging surface or have concave and convex surfaces or have inserts with pipe engaging surfaces which are of varying depths which preferably conform to the outer wall of a pipe which will be held therein or the pipe engaging surface may be concave and provided with a plurality of inserts with pipe engaging surfaces. Preferably, the inserts are provided with gaps therebetween. By having a pipe engaging surface with a large contact area, the pipe engaging surface may be provided with smaller teeth or a less rough, less invasive surface, thus the outer wall of the pipe is less likely to be damaged. This is particularly important for pipes such as premium tubulars and pipes made from brittle alloys, carbon fiber and plastics pipes. However, a planar pipe engaging surfaces may suffice, particularly, but not exclusively, if the planar pipe engaging surface is provided with teeth which bite into the outer wall of the pipe.
Preferably, the interengaging elements comprise an upstand and a recess and most preferably the upstand of the first slip is freely slideable into and out of the recess so that the when the slips are removed from the elevator, the slips are free to part from one another.
Advantageously, the interengaging element of the first slip is in fixed relation to the first slip and the interengaging element of the second slip is in fixed relation to the second slip. Preferably, there are a plurality of interengaging up stands and recesses; the recess may be correspondingly shaped with the upstand, preferably to form an interference fit. The pin may be tapered and the recess may have a corresponding taper.
Preferably, the interengaging element of the first slip is integral with the first slip and the interengaging element of the second slip is integral with the second slip. The interengaging elements may comprise a series of interengaging teeth on each side of the slip.
Advantageously, the slip has a pipe engaging surface. The pipe engaging surface may be arranged on inserts which form part of the slip. The inserts may be arranged in grooves in the body of the slip.
Preferably, the first and second slips each has a pipe engaging surface, a top, a bottom, a rear face and two sides. Advantageously, the interengaging elements are located on or in at least one of the sides. Preferably, the rear face slides along the tapered surface of the body.
Advantageously, the slip actuator sets the at least first and second slips by moving the at least first and second slips down the tapered surface, wherein the interengaging elements allow lateral movement between the first and second slip. Preferably, the tapered surface takes the form of a frusto-conical surface. Thus by allowing freedom to move transverse to the direction of actuation of the slip along the frusto-conical tapered surface the slips can move apart on unsetting the slips and move together on setting the slips. Preferably, the body comprises a main body and at least one door, the tapered surface located on preferably both.
Advantageously, the frusto-conical surface is located on a main body and two doors. The body comprises the main-body and the doors. Thus the weight of the pipe string is carried through the doors as well as the main body.
Preferably, one of the doors comprises a latch and the other of the doors comprises a catch. Preferably, to ensure that the doors are not inadvertently opened or opened by mechanical shock. Advantageously, the main body subtends substantially one hundred and eighty degrees and each of the doors subtends between seventy-five and ninety degrees. Although the main body may subtend any angle, such as thirty degrees and the doors one hundred and sixty-five degrees each. Preferably, the first slip is located on the tapered surface of the main body and the second slip is located on the tapered surface of one of the doors.
The frusto-conical surface may taper from top to bottom along a straight path, or may have a slight convex or concave curvature. The complete frusto-conical surface is commonly referred to as a bowl.
Preferably, a third slip and a fourth slip slidable on the tapered surface, the apparatus further comprising a further slip actuator for setting the at least third slip and the fourth slip, wherein the third slip and the fourth slip have interengaging elements therebetween such that upon actuation of the slip actuator, the third slip is set and the fourth slip is set by the interengaging elements transferring the setting force from the slip actuator through the third slip to the fourth slip.
Alternatively, the first actuating mechanism acts solely on the first slip and sets three or four or more slips simultaneously by transferring the setting force from the first slip through interengaging means on the second third and fourth slips to set all of the slips simultaneously.
Advantageously, the slip actuator is hydraulically actuable. Most advantageously, the slip actuator and further slip actuator are actuable by a common hydraulic circuit, with a common supply of hydraulic fluid, and second preferably, the slip actuator may be, or may include a pneumatic, electrical, or mechanical means such as springs. The present invention also provides in or for use in the apparatus of the invention, a slip having interengaging elements. Preferably, the slip comprises a plurality of grooves, an insert arranged in each of the plurality of grooves. Advantageously, each insert has a pipe engaging surface. Preferably, the pipe engaging surface comprises at least one of the following: tungsten carbide particles, diamond particles, metallic teeth. Preferably, the slip has a pipe engaging surface, a top, a bottom, a rear face and two sides, the interengaging elements located on at least one of the sides.
The invention also provides a method for setting slips in an apparatus for handling pipes of the invention, the method comprising the steps of operating the slips actuating mechanism to apply a setting force to the first slip, whereupon the interengagement means transfers the setting force to the second slip, setting the first and second slips simultaneously.
According to a second aspect of the invention, there is provided an apparatus for handling pipes, the apparatus comprising a body with a tapered surface, a recess in the tapered surface and a pin arranged therein, the apparatus further comprising a slip slideable on the tapered surface, wherein the slip has a lug slideable on the pin, the slip biased by resilient means between the body and the lug to bias the slip into an unset position. Preferably, this allows easy replacement of the slip by withdrawing the pin. Preferably, apparatus further comprises a shoulder arranged in the path of action of the resilient means to inhibit clamping of the lug between the resilient means and the body and preferably defining an opening between the resilient means and the body which is slightly larger than the lug to facilitate easy replacement of the slip.
Once the pin is removed, and upon removal of the slip, the lug of the slip being removed does not cause the resilient means to uncoil or decompress or to lose stored energy. Advantageously, the apparatus further comprises a sleeve about a portion of the pin close to the lug, wherein the resilient means surrounds the sleeve. Advantageously, the sleeve is fixed to the shoulder. Preferably, the shoulder comprises a plate to lie above the resilient means and a leg upstanding from the plate. Advantageously, the body of the elevator further comprises a lug, the resilient means biased between the lug of the slip and the lug of the body of the elevator.
This preferably stabilizes the pin. Preferably, the slip comprises a further lug arranged below the further lug of the body of the elevator. Preferably, the body comprises a ledge against which the lug of the slip is biased. Advantageously, the resilient means comprises at least one of the following: pneumatic piston and cylinder, hydraulic piston and cylinder and an accumulator, a coiled spring, Belville washers, and resilient material such as a foam, but most preferably a compression spring.
The second aspect of the invention also provides a method of changing a slip in an apparatus for handling pipes using the apparatus of the second aspect of the invention, the method comprising the steps of removing the pin from the body 2 and moving the slip to slide the lug thereof out of the recess in the body of the apparatus.
According to a third aspect of the invention, there is provided a method for indicating slips of an elevator have engaged a pipe, the elevator having a slip actuator for actuating slips to engage a pipe, the slip actuator comprising a hydraulically operated piston and cylinder, the method comprising the steps of applying pressurized hydraulic fluid to the piston in the piston and cylinder to move the piston to move the slips into engagement with a pipe, the piston passing a signal port, upon which pressurized hydraulic fluid communicates with hydraulic fluid in a line connected to the signal port, which indicates to the controller that the slips are actuated. Preferably, the line returns to a console from which the controller can observe the increase in pressure using a display of a pressure gauge. Advantageously, the apparatus further comprises a pressure limiting valve, the method further comprising the step of passing the pressurized fluid in line through the pressure limiting valve. Preferably, the increase in pressure is in the order of between 20 bar to 200 bar, most preferably 60 to 150.
Advantageously, the elevator further comprises a door and a latch, the door operated by a hydraulic piston and cylinder, the piston and cylinder having a signal port, the method further comprising the step of applying hydraulic fluid under pressure to the piston and cylinder to move the piston to close the door, whereupon the piston passes the signal port, whereupon hydraulic fluid in a line connected to the signal port is pressurized to initiate activation of the latch. Preferably, the elevator further comprises a hydraulic switch, actuable upon the latch assuming a closed position, which switch allows hydraulic fluid under pressure to flow there through to initiate activation of the slips actuator.
According to a fourth aspect of the present invention, there is provided a method for handling pipe using an elevator having a hydraulic slip actuator for activating slips for engaging a pipe, wherein the elevator further comprises a pilot line, the method comprising the steps of applying pressurized hydraulic fluid to the pilot line to activate the slips actuator to disengage the slips. Preferably, operating the slips actuator to disengage the slips doesn't necessarily mean that the slips themselves will be disengaged. If the pipe is unsupported when the slips actuator is disengaged from the pipe, the weight of the pipe will continue to energise the slips and maintain the slips in the down position with the pipe engaged in the elevator.
The fourth aspect of the present invention also provides an apparatus for handling pipes, the apparatus comprising a body, at least one door and a hydraulic slip actuator for activating at least one slip characterized in that the apparatus further comprises a pilot line and a valve for directing flow of hydraulic fluid into the slip actuator to activate the slips actuator to disengage the slips. This allows the slips to be disengaged whilst the doors and latch remain engaged.
According to a fifth aspect of the present invention, there is provided an apparatus for handling pipes, the apparatus comprising an elevator having a body, at least one ear, and a slip actuator for engaging slips with a pipe said apparatus further comprising a stator attachable to bails of a top drive, the apparatus further comprising a rotor attached to said at least one ear and drive means for rotating said rotor for tilting said elevator with respect to the stator. Preferably, the elevator further comprises at least one door.
The fifth aspect of the present invention also provides a method for handling flush or near flush pipe using an elevator depending from bails of a top drive, the elevator having body and at least one door defining a throat, slips located in the throat and a slip actuator, the method comprising the steps of opening the at least one door of the elevator, tilting the elevator with respect to the bails, placing pipe in a throat of the elevator, closing the doors and activating slips to engage the pipe and hoisting the elevator which allows the elevator to assume its initial position with a pipe depending there from.
By near flush pipes is meant any pipe which does not have an upstand or collar of sufficiently larger diameter than the diameter of the body of the pipe to form an upset from which the pipe can hang when arranged in an elevator having a shoulder on which the upset rests, such as the elevator shown in U.S. Pat. No. 6,494,273.
Preferably, the elevator further comprises a hydraulically actuable piston and cylinder for facilitating opening the door, wherein the method further comprises the steps of opening the doors by raising hydraulic pressure in the actuator, the piston passing a signal port, whereupon a signal is sent which initiates a safety valve which allows the elevator to be tilted. Preferably, the piston and cylinders are double acting, the method further comprising the step of applying pressurized hydraulic fluid to the other side of the piston to disengage the slip actuator.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
For a better understanding of the present invention, reference will now be made, by way of example, to the accompanying drawings, in which:
FIG. 1 is a perspective view of an apparatus in accordance with the present invention;
FIG. 2 is a top plan view of the apparatus shown in FIG. 1 , with a cover plate removed;
FIG. 3 is a front view of the apparatus shown in FIG. 1 ;
FIG. 4 is a back view of the apparatus shown in FIG. 1 ;
FIG. 5 is a fragmentary perspective view showing part of the top and centre of the apparatus shown in FIG. 1 ;
FIG. 6 is a fragmentary perspective view showing parts of the underside and front of the apparatus shown in FIG. 1 ;
FIG. 7 is a cross-sectional view of the apparatus shown in FIG. 1 , taken along the line VII-VII of FIG. 3 , with the slips removed;
FIG. 8 is a fragmentary cross-sectional view of the apparatus shown in FIG. 1 taken along line VIII-VIII of FIG. 3 ;
FIG. 9 is a cross-sectional view of the apparatus shown in FIG. 1 taken along the line IX-IX of FIG. 2 ;
FIG. 10 is a simplified view, similar to the view shown in FIG. 9 , with the slips removed.
FIG. 11 is a cross-sectional view of the apparatus shown in FIG. 1 taken along the line IX-IX of FIG. 2 ;
FIG. 12 is a fragmentary cross-sectional view of the apparatus shown in FIG. 1 taken along the line XII-XII of FIG. 2 ;
FIG. 13 is a fragmentary cross-sectional view of the apparatus shown in FIG. 1 taken along the line XIII-XIII of FIG. 2 ;
FIG. 14 is a schematic representation of part of a drilling rig, including the apparatus shown in FIG. 1 depending from bails;
FIG. 15 is a schematic diagram showing a hydraulic circuit used in the apparatus shown in FIG. 1 ;
FIG. 16 is a graphical representation of steps in the operation of the hydraulic control circuit used to control the elevator shown in FIG. 1 ; and
FIG. 17 is a schematic representation of an apparatus shown in FIG. 1 depending from a pair of bails, the apparatus provided with a device for adjusting the orientation of the apparatus.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIGS. 1 to 13 , there is shown an apparatus of the present invention generally identified by the reference numeral 1 . In the art of handling pipes on a drilling rig, the apparatus 1 is often referred to as an “elevator”. The elevator 1 comprises a part cylindrical body 2 having lifting ears 3 and 4 arranged on opposing sides of the housing 2 for connection to a pair of bails 5 , as shown in FIG. 14 . Doors 6 and 7 are hinged to the body 2 on hinge pins 8 and 9 . A latch 10 is provided to latch the two doors 6 and 7 together to inhibit the doors 6 and 7 from inadvertent opening due to operational mechanical shocks.
The body 2 has a part frusto-conical inner surface 11 which tapers inwardly from the top to the bottom of the body 2 at an angle of approximately ten degrees from vertical to define an open throat 12 , see FIGS. 1 and 10 . From FIG. 7 it can be seen that the part frusto-conical inner surface 11 subtends approximately one hundred and eighty degrees. The doors 6 and 7 each have a part frusto-conical inner surface 13 and 14 which taper inwardly from the top to the bottom at an angle of approximately ten degrees from vertical. The part frusto-conical inner surface 13 and 14 each subtend slightly less than quarter of a circle, approximately eighty-four degrees. When the doors 6 and 7 are closed, a substantially complete frusto-conical surface is defined.
The complete frusto-conical surface may taper from top to bottom along a straight path, or may have a slight convex or concave curvature. The complete frusto-conical surface 11 , 13 and 14 is commonly referred to as a “bowl”.
As can be seen from FIG. 2 , four slips 15 , 16 , 17 and 18 are provided in and line the frusto-conical surfaces 11 , 13 and 14 . Each slip subtends slightly less than ninety degrees in their operating positions. Two of the slips 15 and 17 are arranged on the part frusto-conical inner-surface 11 of the body 2 and each of the other two slips 16 and 17 is arranged on each part of frusto-conical inner surfaces 13 and 14 of each door 6 and 7 . Each slip 15 to 18 has a part frusto-conical outer surface 19 to 22 , which substantially corresponds with the frusto-conical inner surfaces 11 , 13 and 14 , when the slips 15 to 18 are located in a set position. The slips 15 are moveable along the part frusto-conical inner surface 11 to selectively engage (set) and disengage (unset) a pipe (not shown) in the throat 12 of the elevator 1 . The slips 15 to 18 are each provided with a mechanism A, B, C, D for maintaining the slips 15 to 18 in an unset position. Mechanism A will be described for slip 15 , although it will be understood that the slips 16 , 17 and 18 and the mechanisms therefore are generally similar. Referring to FIG. 9 , in which slip 15 is shown in an unset position and FIG. 10 in which the slips 15 and 16 are removed, slip 15 has an upper lug 23 and a lower lug 24 located on a frusto-conical outer surface 19 . The upper lug 23 and lower lug 24 are in vertical alignment and have holes, the centres of which align with a line parallel to the part frusto-conical outer wall 19 . The upper lug 23 and lower lug 24 are slidably arranged on a pin 25 . The pin 25 is arranged in a recess 26 in the part frusto-conical inner surface 11 and lies substantially parallel therewith and is retained in a hole in a lower projection 27 and in a hole in an upper projection 28 of the body 2 . The lower lug 24 of the slip 15 is arranged on the pin 25 beneath the projection 27 and the upper lug 23 of the slip 15 is arranged between the lower and upper projections 27 and 28 . A spring 29 is arranged about the pin 25 and a sleeve 30 between the lower projection 27 and a lip 31 on the upper end of the sleeve 30 on which upper lug 23 seats.
The sleeve 30 has a back portion 32 , the top of which sits against the bottom of a small groove 32 a . The spring 29 biases the back portion 32 of the sleeve 30 against the bottom of the small groove 32 . The back portion 32 , the upper projection 27 and the lip 31 define an opening and the distance between the upper projection 27 and the lip 31 is slightly larger than the upper lug 23 ′, such that the upper lug can slide into and out of the opening.
The spring force in the coiled spring 29 is greater than the weight of the slip, thus the spring 29 maintains the slip 15 in a raised, unset, disengaged position.
The pin 25 is slideably removable from the hole in the lower projection 27 , through the spring 29 , sleeve 30 and upper projection 28 . By removing the pin 25 , the slip 15 can be removed and changed for a different slip of the same type or size, or a slip of a different size suitable for handling pipe of a different diameter or a pipe of a different kind, such as premium tubular, which might require pipe engaging teeth of a different kind to reduce the possibility of damage to the surface of the tubular.
The pin 25 is then slid back through upper projection 28 , sleeve 30 , spring 29 and lower projection 27 . The pin 25 may be threaded to threadedly engage the upper or lower lugs 27 and 28 , or may have a smooth interference fit surface or may be a loose fit and may be prevent from falling out lugs 27 and 28 by a member lying over the top of the pin 25 . Each slip 15 to 18 is provided with a top projection 15 a , 17 a and (not shown) with a hole therein to facilitate removal and replacement.
For an elevator 1 as described herein, the slips 15 to 18 can be exchanged for one of six different sizes for handling pipe sizes between 2⅜″-2⅞″. For the first size set of slips, 2⅞″-3½″ for the second size set of slips, 3½″-4½″ for the third size set of slips, 4½″-5½″ for the fourth size set of slips, 5⅝″-6⅝″ for the fifth size set of slips and 6⅝″-7⅝″ for the sixth size set of slips. The elevator 1 is preferably suitable for holding pipe string loads of 227 tonnes (250 short tons) and in other embodiments 454 tonnes (500 short tons), 681 tonnes (750 short tons) 907 tonnes (1000 short tons).
The slip 15 has a solid body, which may be made of any material suitable for resisting compression forces of in excess of 227 Tonnes (250 short tons) and in other embodiments 454 tonnes (500 short tons), 681 tonnes (750 short tons) 907 tonnes (1000 short tons) or more. The solid body has three grooves 33 , 34 , 35 therein running from top to bottom, as shown in FIG. 5 . The grooves 33 , 34 , 35 converge towards the lower end. Inserts 36 , 37 , 38 which correspondingly converge towards a lower end, are slid into corresponding grooves 33 , 34 , 35 . The inserts have a pipe engaging surface 39 , which may be any suitable finish or material, such as tungsten carbide particles, diamond particles, metallic teeth, or any material which resists slippage.
The slip 15 also has a recess 37 a in one side of the slip for receiving a corresponding upstand 38 a on adjacent slip 16 . Slip 17 has a corresponding upstand (not shown) on the opposing side of the slip 17 to fit into a corresponding recess (not shown) in slip 18 . The upstand 38 a is tapered and the recess 37 a is correspondingly tapered, although in another embodiment, both the upstand 38 a and the recess 37 may not be provided with tapers. Each slip 15 to 18 may thus be provided with an upstand and a corresponding recess, such that when fitted together, downward force can be transmitted through the upstand and recesses to adjacent slips, so that a setting force can be applied to one slip to transmit the setting force through the upstand and recesses to set one further or all the slips 15 to 18 simultaneously on a pipe. The upstand 38 a and recess 37 a allow a radial movement therebetween such that the slips can move apart when being moved up into an unset position along the part frusto-conical inner surfaces 11 , 13 and 14 and move together when the slips are moved down the part frusto-conical inner surfaces 11 , 13 and 14 into the set position, whilst still able to transmit the downward forces between the slips required to set the slips on a pipe. Preferably, the upstand 38 a and corresponding recess 37 a have an interference fit. Thus the slips interengage to transmit longitudinal force, whilst retaining the ability to radially contract and expand between one another.
The slips 15 to 18 are set using a slip activation mechanism. The slip activation mechanism comprises two slips actuating mechanisms 40 and 41 which are generally similar to one another, one located on the left side of the body 2 and the other on the right side of body 2 .
Slips actuating mechanism 40 will be described for activating slips 15 and 16 , although it will be understood that the slips actuating mechanism 41 is generally similar for activating slips 17 and 18 . Slips actuating mechanism 40 comprises piston 42 and a cylinder 43 defining a chamber 44 and an annulus 45 . The hydraulic fluid contact area on the piston provided by the annulus 45 is approximately the same as the hydraulic fluid contact area on the piston provided by the chamber 44 . A recess 46 is located in the top of the piston 42 for slideably receiving a pin 47 . The pin 47 has a hole 48 therein transverse to the length of the pin 47 for receiving a lever 49 . The lever 49 is rotatably arranged on a substantially horizontally disposed pin 50 on a lug 51 fixed to the body 2 . The lever 49 is shaped so that there is a defined distance between the lever 49 and the body 2 to limit the vertical travel of the lever 49 . The lever 49 has an integral finger portion 52 which lies above part frusto-conical inner surface 11 and above top projection 15 a of the slip 15 , when there is a slip 15 in the elevator 1 . Upon activation of the slips actuating mechanism 40 , hydraulic pressure is increased in chamber 44 causing hydraulic fluid to flow into chamber 44 and inducing upward movement of the piston 42 and hydraulic fluid to flow out of annulus 45 . The pin 47 is pushed up with the piston 42 , which moves lever 49 upwardly about the pin 50 and thus finger 52 downwardly on to the top of the slip 15 to provide a setting force which compresses the spring 29 of mechanism A and the spring (not shown) of mechanism B by transfer of the setting force through the projection 38 a and recess 37 a to engage a pipe (not shown). The hydraulic actuating mechanism 41 is actuated in a similar way to set slips 17 and 18 . All slips 15 to 18 are set simultaneously on the pipe. The hydraulic force provided by the slips actuating mechanisms 40 and 41 is preferably sufficient to cause the pipe engaging surface 39 of the slip 15 to bite into the wall of the pipe. The elevator 1 is lifted on the bails 5 and the weight of the pipe causes the pipe further engage surfaces 39 of the slips 15 to bite into the surface of the pipe. The hydraulic actuating mechanism transfers approximately 4.5 tonnes (five short tons) of setting force to the slips 15 to 18 . The hydraulic pressure is maintained during the handling of the pipe to inhibit the pipe from disengaging, even if there is an upward force of about 4.5 tonnes (five short tons) of upward force applied to the pipe.
The spring force on each spring 29 is approximately 300N to 500N sufficient to hold a slip in the raised, unset condition. The slips 15 to 18 weigh in one embodiment between ICON and 300N each, i.e. the spring force of each spring is greater than the weight of each slip 15 to 18 , so that the spring 29 will maintain the slip is a raised, unset, disengaged position.
Hydraulic pressure may be increased in the annulus 45 and/or decreased in the chamber 44 to retract the piston 42 . This allows the pin 47 to fall back into the recess 46 and the lever to rotate about pin 50 to lift the finger 52 out of engagement with the top projection 15 a of the slip 15 . Due to the weight of the pipe being greater than the spring force provided by the springs 29 and the corresponding springs in mechanisms B, C and D, the slips 15 to 18 will maintain a grip on the pipe until a upward force is exerted to sufficiently reduce the effective weight of the pipe, which will disengage the pipe engaging surface 39 of the slips 15 to 18 which will allow the spring 29 and the springs of the mechanism B, C and D to expand to return the slips 15 and 18 to a raised, unset, disengaged position. Such an upward force on the pipe may be provided by the pipe having been stabbed and connected to a pipe string, the pipe string being held in a spider, thus the weight of the pipe is taken by the drill string which allows the springs 29 to lift the slips out of engagement with the pipe. Further lowering of the elevator 1 would help disengage the slips 15 to 18 , but this would only be required occasionally or in exceptional circumstances.
Referring back to FIG. 1 , a cover 53 is provided to protect the slips actuating mechanisms 40 and 41 from being knocked or clogged with dirt, drilling mud and debris. The cover is hinged on a hinge 54 and a handle 55 is provided for lifting the cover to gain access to the actuating mechanisms 40 and 41 and to mechanisms A and C.
The cover 53 also has a U-shaped cut out 56 and a plastics material or metal buffer, preferably a soft ductile metal buffer 57 , which acts as a pipe guide to facilitate locating a pipe in the throat 12 of the elevator 1 .
A pipe to be handled is offered up to the elevator 1 when the doors 6 and 7 of the elevator 1 are open.
Referring to FIGS. 3 and 7 , to open the doors 6 and 7 , the latch 10 is released. The latch 10 comprises a locking bar 58 on upper and lower arms 59 and 60 which are hinged with a hinge pin 61 to door 6 . A curved linkage arm 62 is located in a recess 63 in the door 6 .
The curved linkage arm 62 has two opposed ends, one end linked to the lower arm 60 , off-centre from the hinge pin 61 and the other end to a bearing 64 freely rotatable around hinge pin 8 of door 6 . A further linkage arm 65 is located in an opening 66 in the body 2 of the elevator 1 extending from the front of the elevator 1 to the back of the elevator 1 past the lifting ear 3 . The further linkage arm 65 has two opposed ends one linked to the bearing 64 and the other to an elbow linkage 67 which is linked to a piston 68 of a double acting piston and cylinder 69 , as shown in FIG. 4 . Upon hydraulic fluid pressure increasing in an annulus 68 a behind the piston 68 in the cylinder 68 and/or decreasing in a chamber 68 b in front of the piston 68 , the piston 68 retracts pulling elbow linkage 67 and linkage arm 65 to rotate bearing 64 and pull the curved linkage arm 62 to rotate the latch 10 about the hinge pin 61 to unlatch the latching locking bar 58 from engagement with a catch 71 on the door 7 .
The doors 6 and 7 are then opened. Linkage arms 72 and 73 each have two opposed ends and are arranged in openings which pass from the front to the back of elevator 1 . One end of the linkage arm 72 and 73 is located in a recess 74 and 75 and attached to their respective doors 6 and 7 at a point which is offset from the hinge pins 8 and 9 . The other end of each linkage arms 72 and 73 is attached to an elbow linkage 76 and 77 respectively, which are rotatable about pins 78 and 79 .
The other end of elbow linkages 76 and 77 are attached to piston and cylinder 80 . An upstand 81 is slideably arranged in fingers 82 to allow the piton and cylinder 80 to move longitudinally. Upon hydraulic fluid pressure increasing in an annulus 83 behind the piston head, the piston 84 retracts into the cylinder 85 which pulls the ends of elbow linkages 76 and 77 to rotate the elbow linkages about pins 78 and 79 , which transfer a the pulling force into a pushing force on linkage arms 72 and 73 to open the doors 6 and 7 .
A pipe is swung into or offered up to, or the elevator 1 is offered up to the pipe, through the open doors 6 and 7 into the throat 12 of the elevator 1 and abuts the buffer 57 of the pipe guide arranged in the U-shaped cut-out 56 in the cover 53 . The doors 6 and 7 are closed by raising the pressure in a chamber 86 and/or lowering the pressure of the hydraulic fluid in the annulus 83 of piston and cylinder 80 , which extends the piston 84 and moves the piston 84 to the left when referring to FIG. 4 and the cylinder 85 moves to the right, both the piston 84 and cylinder 85 moving longitudinally, which pushes the ends of elbow linkages 76 and 77 to rotate the elbow linkages about pins 78 and 79 , which transfers the pushing force into a pulling force on linkage arms 72 and 73 to close the doors 6 and 7 about the pipe. As shown in FIG. 5 , plastics material or metal, preferably a soft ductile metal, buffers 86 and 87 is provided on the edge of a curved cut-out 88 and 89 on cover plates 90 and 91 located on the top surface of the doors 6 and 7 . The buffers 86 and 87 act as a pipe guide to facilitate the locating a pipe into the throat 12 of the elevator 1 upon closing the doors 6 and 7 . The buffers 86 and 87 are bolted to cover plates 90 and 91 .
Buffers 92 , 93 and 94 are provided on the underside of the elevator 1 in cover plates 95 , 96 and 97 , as shown in FIG. 6 .
The doors 6 and 7 take a substantial portion of the weight of the pipe and are thus built to withstand 227 tonnes (250 short tons) of force and in other embodiments 454 tonnes (500 short tons), 681 tonnes (750 short tons) and 907 tonnes (1000 short tons). The latch maintains the doors 6 and 7 closed, and thus must be substantial and withstand the spreading force of the slips as they engage the pipe. The latch 10 is built to withstand 227 tonnes (250 short tons) of force and in other embodiments 454 tonnes (500 short tons), 681 tonnes (750 short tons) and 907 tonnes (1000 short tons) in tension between the doors 6 and 7 .
Referring to FIG. 3 , the lifting ears 3 and 4 comprise lower lugs 98 and 99 and upper shoulder 98 a and 99 a integral with or welded to the body 2 . Curved locking arms 98 b and 99 b are attached at either ends with pins, so that the curved locking arms 98 b and 99 b can be removed. Curved locking arm 98 b has an integral lug 98 c and a slot 99 d therein for receiving a mechanism for tilting the elevator whilst attached to the bails 5 of a top drive (not shown). The tilting mechanism is sold by BJVarco and is used in conjunction with the state of art BX elevator currently available. Such an arrangement is shown in FIG. 17 .
A hydraulic system is provided for controlling the operation of the elevator 1 . The hydraulic system is shown schematically in FIG. 15 , which shows the system in a state in which the slips are retracted, disengaged, unset and the latch and doors are open. An operator controls the hydraulic system from a control console 100 in an operator's cabin (not shown). Hydraulic fluid flows through the system at between 7.5 and 20 litres per minute (2 to 5 gallons per minute) and is supplied whilst the elevator 1 is being operated.
To close the doors 6 and 7 , latch 10 and set the slips 15 to 18 , the following steps are taken. Using the control panel 100 , an operator operates a system valve (not shown) to set the hydraulic pressure in line P to a high pressure of between 124 to 159 bars (1800 to 2300 psi) and leaves the hydraulic pressure in line XP at atmospheric pressure. The hydraulic fluid passes in line P through a filter 101 . The increase in pressure in the hydraulic fluid passes through line 102 and into control line 103 which shifts slide valve 104 to allow the increase in hydraulic pressure to pass from line 102 to line 105 and into line 106 . Chamber 86 of door piston and cylinder 80 shifts the piston 84 into an extended position, closing the doors 6 and 7 . Fluid is forced out of the annulus 83 into line 107 through check valve 108 into line 109 and into line 110 and through slide valve 104 and into line 111 and into line T. When the piston head of piston 84 passes a signal port 112 , high pressure from line 106 communicates therewith and applies high pressure hydraulic fluid in signal line 113 , which opens check valve 113 a and allows hydraulic fluid at a high pressure to pass from line 106 across the check valve 113 a to line 114 into the chamber 68 b of the latch piston and cylinder 69 . The build up of high pressure hydraulic fluid in chamber 68 b pushes on piston head of piston 68 to move the piston 68 into an extended position closing the latch 10 .
A latch detection valve 116 is located between the latch 10 and the door 7 , such that upon closing of the latch 10 , the latch detection valve 116 shifts to allow high pressure hydraulic fluid to pass thereacross between line 117 , which is in fluid communication with line 105 , and signal line 118 . High pressure hydraulic fluid in signal line 118 passes into signal line 119 opening the check valve 120 , allowing high pressure hydraulic fluid to pass across check valve 120 between line 121 , which is in fluid communication with line 114 , and line 122 . High pressure hydraulic fluid flows on from line 122 through slide valve 123 into line 124 into lines 125 and 126 and into chambers 44 and 44 a of slip actuating mechanism, piston and cylinders 40 and 41 , which shift the pistons 42 and 42 a into extended positions moving fingers 52 and 52 a downwardly on to the slips 15 and 17 against springs 29 and 29 a to set the slips 15 to 18 on a pipe (not shown). The slips 15 to 18 are set with a hydraulic power down force of approximately 4.5 tonnes (5 short tons), which is enough to create an initial penetration of the teeth of a standard set of inserts located on the slips 15 to 18 into a wall of the pipe, inhibiting the pipe from slipping through the slips 15 to 18 and allowing the buildup of the downward hoist load. The hydraulic fluid in the annuli 45 and 45 a is squeezed into lines 127 , 128 and into line 129 , through slide valve 123 into line 130 into line 131 , through slide valve 104 , through line 111 and out into line T. When the piston 41 is in an extended position, which indicates the slips 15 to 18 are set, high pressure hydraulic fluid passes through signal line 132 to a slips down detection valve 133 , which high pressure hydraulic fluid shifts the slips down detection valve 133 allowing high pressure 124 to 159 bars (1800 to 2300 psi) pneumatic fluid to communicate between signal line 118 and signal line 134 . The slips down detection valve 132 will shift to be in fluid communication between signal lines 118 and 134 upon a pressure greater than 103 bars (1500 psi). The high pressure in the hydraulic fluid from line 118 passes into line 134 and through a pressure limiting valve 135 , which limits the pressure flowing onwards to check valve 136 to approximately 69 bars (1000 psi), and into line XP with a pressure of approximately 69 bars (1000 psi) to indicate to the operator that the doors 6 and 7 are closed, the latch 10 is closed and the slips 15 to 18 are set. This is a step increase in pressure at XP from atmospheric to approximately 69 bars (1000 psi) which is easily noticeable by an operator. The slips down detection valve 133 will then return to its initial state by high pressure hydraulic fluid flowing through control line 133 b through a restrictor 133 a , which delays the onset of high pressure on the opposing side of the slips down detection valve 133 . The spring force on the slips down detection valve returns the valve to its initial state in which it blocks fluid communication between signal lines 118 and 134 .
Once the slips 15 to 18 are set, the elevator 1 is lifted and the weight of the pipe self-energises the slips 15 to 18 , and thus are firmly held by the slips 15 to 18 . If, for any reason, an upward force on the pipe occurs of up to 4.5 tonnes (5 short tons), the slips 15 to 18 will remain engaged due to the pistons 42 and 42 a remaining in the extended position, which are held set by a force of at least 4.5 tonnes (5 short tons) of hydraulic force to the top of the slips. The high pressure hydraulic fluid is maintained at high pressure whilst the elevator 1 is in use. High pressure through line P is maintained throughout use of the elevator 1 .
The slips 15 to 18 may be released whilst maintaining the doors 6 and 7 and latch 10 closed. This is accomplished using a slips activation system 200 . The first step is to activate a PILOT valve (not shown) on the control panel 100 to allow, preferably 138 to 172 bars (2000 to 2500 psi) to flow through line 201 which activates slide valve 202 , which requires a minimum of 103 bars (1500 psi) to operate to allow fluid communication between signal line 118 and line 203 , which applies a high pressure to slide valve 123 , shifting the valve to allow line 122 to communicate with line 129 . The high pressure hydraulic fluid flows through lines 127 and 128 applying high pressure hydraulic fluid to annuli 45 and 45 a , which retracts pistons 42 and 42 a which allows the fingers 52 and 52 a free to hinge about hinge points 50 and 50 a . Hydraulic fluid in chambers 44 and 44 a flows through lines 125 , 126 , through sliding valve 123 into line 130 , through the line 131 , through slide valve 104 into line 111 and into line T. The freely hinged fingers 52 and 52 a allow the slips 15 to 18 to move to a retracted, disengaged, unset position on springs 29 , 29 a and (not shown), unless the weight of the pipe being held therein is not supported, in which case the slips 15 to 18 will remain engaged with the pipe due to the self-energising nature of the slips 15 to 18 .
The latch 10 is opened and the doors 6 and 7 are then opened by maintaining the hydraulic pressure in line P at a high pressure of between 124 to 159 bars (1800 to 2300 psi) and operating XP valve (not shown) from the control panel 100 to allow hydraulic pressure of a greater pressure, preferably 14 bars (200 psi greater) i.e. between 138 to 172 bars (2000 to 2500 psi) to flow through line XP. The hydraulic fluid passes through the filter 101 . The increase in pressure in the hydraulic fluid passes through line 102 and into control line 103 , which pushes the valve 104 , but is resisted and overcome by the pressure in line 137 applied by the pressure in line XP. The greater pressure in line XP flows through a filter 138 into a control line 139 which overcomes 103 bars (1500 psi) required to shift valve 140 to allow fluid communication between line XP and line 137 . Hydraulic fluid at high pressure is allowed to flow from line 102 into line 131 , line 110 and into the annulus 68 a of the latch piston and cylinder 69 at a pressure of between 124 to 159 bar (1800-2300 psi), which causes the piston 68 to retract, unlatching the latch 10 . The hydraulic fluid in chamber 68 b is now at atmospheric pressure and flows through line 114 past check valve 113 a into line 106 , through slide valve 104 , into line 111 a and into line T.
Once the piston has retracted fully and thus unlatched the latch 10 , the piston head passes a signal port 141 .
High pressure hydraulic fluid is allowed to pass through signal port 141 and through signal line 142 to activate check valve 108 to allow high pressure hydraulic fluid to flow through from line 110 , through line 109 across check valve 108 into line 107 and into annulus 83 of: the piston and cylinder 69 to retract the piston 84 to open the doors 6 and 7 . Hydraulic fluid squeezed out of chamber 86 flows through line 106 through slide valve 104 into line 127 and out of line T.
It should be noted that slips activation system 200 can be activated at any time to release the fingers 52 and 52 a from engagement with slips 15 and 17 . This is particularly important for applications where it is needed to allow the pipe to be released and re-gripped.
The slips activation system 200 may be replaced by or complemented by a hydraulic circuit which activates the pistons 42 and 42 a of slips piston and cylinders 40 and 41 to automatically retract upon applying the greater pressure to line XP for opening the latch 10 and the doors 6 and 7 . This can be accomplished by having a link between the XP valve and the PILOT valve, so that on activating the XP valve, the PILOT valve is activates, but when the PILOT valve is activated, the XP isn't activated. The slips activation system 200 is an optional system and may not be required in certain applications.
The hydraulic control circuit is housed in a box 145 located on the rear of the elevator 1 , as shown in FIG. 4 . A hydraulic control manifold 146 , shown in FIG. 11 is provided on the elevator 1 for connecting the P line, T line, XP line, PILOT line and a FLOAT line 147 from the control panel 100 to the elevator 1 . The hydraulic lines 144 connected to the manifold 146 may hang free or be bound into one umbilical and lead to a part of the derrick DR or to a top drive from which the elevator 1 may depend and onward to the control console 100 and to a source of hydraulic fluid and means for pressurizing the hydraulic fluid, which are commonly available on drilling rigs and platforms.
FIG. 16 shows a graphical representation of steps in the operation of the hydraulic control circuit against time, starting with the elevator 1 in an open position with a pipe in the throat 12 ready to be engaged and hoisted. The first step shown is the doors closing 301 , when the doors are sufficiently closed, a signal 302 is sent to start the latch closing step 303 . Once the latch is sufficiently closed, a signal 304 is sent to allow operation of the slips. The slips pistons 42 and 42 a are extended 305 to set the slips. The slips are now set 306 , and a signal 307 of 69 bar (1000 psi) is sent to the XP port to indicate to the operator that the slips 15 to 18 are set. A pressure 308 is applied to the PILOT line 201 to retract the pistons 42 and 42 a for disengaging the slips 15 to 18 . Pressure 308 of between 138 to 172 bars (2000 to 2500 psi) in the pilot line is moved to atmospheric 309 , whereupon slips pistons 42 and 42 a are extended 310 to set 311 the slips 15 to 18 , and a signal 313 of 69 bar (1000 psi) is sent to the XP port to indicate to the operator that the slips 15 to 18 are set.
A greater pressure of 138 to 172 bars (2000 to 2500 psi) is applied 314 to port XP and a pressure of 138 to 172 bars (2000 to 2500 psi) is applied 315 to the PILOT line to retract 316 the slips and the opening sequence commences with latch 10 opening 317 , whereupon a latch open signal 318 initiates door 6 and 7 opening 319 . It should be noted that the pressure 320 in line P of between 124 to 159 bar (1800-2300 psi) is maintained throughout the operation.
Optionally, the elevator 1 can be tilted by a device 400 , as shown in FIG. 17 . The elevator 1 depends from bails 5 . The device 400 comprises plates 401 rigidly secured to bails 5 . The plates 401 each have a hydraulic motor 402 having a stator 403 fixed to the plates 401 and a rotor 404 attached to the ears 3 and 4 the elevator 1 , so that upon activation of the rotors 404 , the elevator 1 is tilted for receiving a pipe lying at an angle between horizontal and vertical through the doors 6 and 7 into the throat 12 of the elevator 1 . This allows picking up pipe from or laying pipe down on the ramp leading to the opening in the derrick known as the V-door. Such a mechanism is used on the state of the art BX elevator sold by BJVarco. Preferably, the FLOAT line 147 is used in conjunction with a hydraulic system (not shown) for operating the device 400 , for providing a signal to allow the hydraulic system for the device 400 to rotate only when the slips are down, latch 10 is unlatched and the doors 6 and 7 are open, to prevent the device 400 from being operated when the elevator has a pipe therein.
In conclusion, therefore, it is seen that the present invention and the embodiments disclosed herein and those covered by the appended claims are well adapted to carry out the objectives and obtain the ends set forth. Certain changes can be made in the subject matter without departing from the spirit and the scope of this invention. It is realized that changes are possible within the scope of this invention and it is further intended that each element or step recited in any of the following claims is to be understood as referring to the step literally and/or to all equivalent elements or steps. The following claims are intended to cover the invention as broadly as legally possible in whatever form it may be utilized. The invention claimed herein is new and novel in accordance with 35 U.S.C. 102 and satisfies the conditions for patentability in 102. The invention claimed herein is not obvious in accordance with 35 U.S.C. 103 and satisfies the conditions for patentability in 103. This specification and the claims that follow are in accordance with all of the requirements of 35 U.S.C. 112. The inventors may rely on the Doctrine of Equivalents to determine and assess the scope of their invention and of the claims that follow as they may pertain to apparatus not materially departing from, but outside of, the literal scope of the invention as set forth in the following claims. All patents and applications identified herein are incorporated fully herein for all purposes | An apparatus for handling pipes, the apparatus, in certain aspects, having a body having a tapered surface and at least a first slip and a second slip slidable on the tapered surface, a slip actuator for setting said at least first slip and said second slip, said first slip and said second slip having interengaging elements such that upon actuation of said slip actuator, said first slip is set and said second slip is set by the interengaging elements transferring setting force from the slip actuator through said first slip to said second slip; and methods for using such an apparatus. | 4 |
This application is a continuation application of co-pending U.S. patent application Ser. No. 12/960,199, filed Dec. 3, 2010, entitled “Method and Apparatus for Sorting Materials According to Relative Composition,” which is hereby incorporated by reference, which is a continuation application of U.S. patent application Ser. No. 12/493,578, filed Jun. 29, 2009, now U.S. Pat. No. 7,848,484, entitled “Method and Apparatus for Sorting Materials According to Relative Composition,” which is hereby incorporated by reference, which is a continuation application of U.S. patent application Ser. No. 11/498,694, filed Aug. 3, 2006, now U.S. Pat. No. 7,564,943, entitled “Method and Apparatus for Sorting Materials According to Relative Composition,” which is hereby incorporated by reference, which is a continuation-in-part application of U.S. patent application Ser. No. 11/069,243, filed Mar. 1, 2005, now U.S. Pat. No. 7,099,433, entitled “Method and Apparatus for Sorting Materials According to Relative Composition,” which is hereby incorporated by reference, which claims benefit of U.S. Provisional Pat. App. Ser. No. 60/549,089, filed Mar. 1, 2004, entitled “High speed non-ferrous metal sorting using XRF ” which is hereby incorporated by reference in its entirety.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
This invention was made with federal grant money under National Science Foundation Small Business Innovation Research program under grant number DMI-0239055.The United States Government has certain rights in this invention.
Be it known that we, Edward J. Sommer, Jr., a citizen of the United States and a resident of Nashville, Tenn., Charles E. Roos, a citizen of the United States and a resident of Nashville, Tenn., David B. Spencer, a citizen of the United States and a resident of Bedford, Mass., and R. Lynn Conley, a citizen of the United States and a resident of Antioch, Tenn. have invented a new and useful “Method and Apparatus for Sorting Materials According to Relative Composition.”
BACKGROUND OF THE INVENTION
In the scrap metals recycling industry there is a lack of an environmentally clean low cost technology to reliably segregate post-consumer metal scrap into its various metal constituents. Current practice for sorting aluminum metals from other nonmagnetic metals derived from scrap sources such as automobile shredders is to either sort by hand labor or to introduce the mixed metals into a liquid heavy media where the aluminum floats and the heavier nonmagnetic metals sink. Hand labor is far too slow and very expensive. The heavy media process is capital intensive, has high operating costs, and uses a water slurry mixed with chemicals to raise the specific gravity of the liquid to a value above that of aluminum (2.7 gm/cc). The liquid media requires treatment in a wastewater treatment facility. The resulting sludge composed of grease, oil, dirt, and chemicals poses significant disposal issues as do water discharges. Additionally to be cost effective the heavy media process requires a large installation and is normally deployed as a regional facility. This requires the producers of scrap to ship their metals to this regional facility for separation before the metal products can be shipped to market, whereas if sorting could be accomplished locally the scrap producers could ship directly to market. Elimination of the extra shipping requirement would improve the economics of recycling and remove the burden on our environment caused by the shipping of hundreds of thousands of tons of scrap metals annually to regional heavy media plants.
There have been recent efforts to develop dry environmentally friendly techniques to sort low atomic number light weight metals and alloys such as magnesium (atomic number Z=12) and aluminum (Z=13) and their alloys from higher atomic number heavier metals such as iron (Z=26), copper (z=29), and zinc (Z=30) and their alloys. One method is to acquire and analyze x-ray fluorescence spectra derived from metals by irradiating metals with excitation x-rays, measuring the resulting x-ray fluorescence emitted from the metals, utilizing spectral information developed from the measurements to identify composition of the metals, and to mechanically sort the metals according to their compositions. This method is exemplified by U.S. Pat. Nos. 6,266,390, 6,519,315, and 6,888,917. Low Z material does not lend itself well to x-ray fluorescence analysis since x-ray photons fluoresced from low Z materials are at low yield and are low energy (˜1-2 kev). Because they are low energy they are easily absorbed in air before reaching the detection system. This method also, by nature of the detection system, requires a significant time interval to build and analyze spectral information for each piece of material analyzed. Consequently systems that operate according to this method are limited in throughput rate of materials. For high throughput rates it is desired to have a faster acting analyses system in order to process materials faster and at greater volumes.
Another effort is described in Patent Application Publication No. US2004/0066890 wherein is discussed a process of irradiating materials by x-ray radiation, measuring x-ray transmission values through materials at two different energy levels, and using these measurements to determine the thickness and composition of a material. However, that publication does not reveal how such determinations can be accomplished. That dual energy system, as described, discusses utilizing undisclosed image processing techniques and appears similar to standard security x-ray scanners, such as those used at security checkpoints in airports, which utilize x-ray measurements at two different energy levels to measure thickness and material composition and present on a computer monitor screen a complex image for human visual inspection which is graphically encoded by image intensity and false color mapping to represent thickness and material composition (as described by security x-ray scanner vendor Smith's Heimann). Some such x-ray scanners utilize a physically stacked dual energy x-ray detector array to measure x-ray transmission values through materials over two energy ranges, the fundamental features of which are described by GE Medical Systems in their U.S. Pat. Nos. 4,626,688 and RE 37,536. A stacked dual energy detector utilizes a physical geometry of having a lower energy detector sandwiched with a higher energy detector with a filter, typically a metal layer such as copper, interposed between the two detectors. X-rays to be measured first enter the detector stack into the lower energy detector. Lower energy photons are absorbed by the lower energy detector as they are measured. Mid-energy and higher energy photons pass through the lower energy detector. Mid-energy photons are absorbed in the filter layer between the two detectors while higher energy photons pass through the filter layer and are measured by the higher energy detector at the back of the stack. Other x-ray scanners utilize other types of dual energy detector arrangements, such as side-by-side arrays, examples of which are disclosed in U.S. Pat. Nos. 5,841,832 and 5,841,833.
Still another effort utilizes spectral analysis of plasma evaporated off the surface of metal samples induced by momentarily striking the metals with a focused high power laser beam. This method, referred to as Laser Induced Breakdown Spectroscopy or LIBS, reportedly has been practiced in the U.S. by a metals processing company and is detailed in U.S. Pat. No. 6,545,240 B2. The LIBS process for sorting of metals as they are conveyed in volume through a processing line involves a high level of complexity due in part to requirements to rapidly steer a laser beam to small target points from sample to sample for repeated bursts of laser light and to correspondingly steer spectral acquisition optics from sample to sample in coincidence with the laser beam. This method is very complex and costly.
In sorting of many materials, such as nonferrous automobile scrap, it is very advantageous to be able to sort lighter weight materials (such as aluminum and its alloys) from heavier weight materials (such as iron, copper, and zinc and their alloys). To accomplish such a sort it is not necessary to determine both thickness and composition as the method of US2004/0066890 claims to do and it is not necessary to use complex image processing techniques of US2004/0066890 and as practiced using security x-ray scanners. Instead a determination of relative composition, such as relative average atomic number (Z), suffices to make a very valuable sort of the materials. Determination of relative composition, such as in discriminating high Z materials from low Z materials, is simpler for a detection system to accomplish than is determination of thickness and composition which can require high precision detector signals to be able to discern fine differences in measurements from sample to sample, maintenance of comprehensive detection system calibrations, and use of complex pattern matching algorithms such as those used by human visual inspectors in interpreting processed images produced by security x-ray scanners. At this time it has not been technically possible to duplicate by computerized algorithms the complex visual pattern matching skills used by humans in interpreting processed images produced by dual energy x-ray scanner security systems.
SUMMARY OF THE INVENTION
The present invention discloses a metal sorting device and method of use thereof. The metal sorting device, used to distinguish materials of differing atomic weight, includes an X-ray tube, a dual energy detector array positioned to receive x-rays from the X-ray tube, a microprocessor operationally connected to the dual energy detector array, an air ejector controller operationally connected to the microprocessor, and an air ejector array attached to the air ejector controller. The device may include a conveyor belt disposed between the X-ray tube and the dual energy detector array. Certain embodiments of the invention include an air ejector array having at least two air ejectors. Other embodiments of the invention include an air ejector array having as few as one air ejector and others as many as 128 or more air ejectors. Other embodiments of the invention include a collection bin, or at least two collection bins. In certain embodiments, the device includes a dual energy detector array further including dual energy x-ray detectors and a data acquisition system. In another embodiment the dual energy detector array utilizes stacked dual energy detectors.
One embodiment of the invention includes a method of detecting and sorting materials of differing atomic weight, the method includes providing a sample, placing the sample in a sensing region of a dual energy detector array, detecting the sample in the sensing region, reading a high energy sensor value, reading a low energy sensor value, normalizing the high energy sensor value, normalizing the low energy sensor value, computing a ratio of high energy value to low energy value, correlating the ratio with the normalized high energy value, determining whether the correlation is in a high atomic number region or a low atomic number region, transporting the sample to an air ejection array, and energizing at least one air ejector of the air ejection array.
Thickness is typically not a factor in quality of sorted materials for users of many sorted materials such as nonferrous automobile scrap. Consequently it would be advantageous to have an automated sorting system to measure the relative composition of materials processed through the system directly without regard to thickness of the materials and without applying complex pattern matching techniques through image processing. Determination of relative composition independent of material thickness simplifies computerized identification and sorting algorithms by reducing complications arising from processing additional dual energy transmission information with regard to thickness. In this way the algorithms can operate rapidly, accurately, and robustly to identify materials by relative composition and reliably provide signals to rapid sorting mechanisms to effect sorting of the materials according to their measured relative compositions at high throughput rates of materials. It is an objective of the present invention to provide such method and apparatus for thickness independent measurement of material relative composition with accompanying high throughput sorting of the materials according to relative composition.
The present invention incorporates computerized processing of measurements of amounts of transmission of x-ray photons through materials at two separate energy levels (dual energy detection), as illustrated above by way of example, to distinguish materials of relatively high Z from materials of relatively low Z by comparing results of the processing to an experimentally determined preset threshold level which varies as a function of amount of photon energy transmitted through such materials, and responsive to such determinations activates mechanical sorting mechanisms to segregate the relatively high Z materials from the relatively low Z materials, as is further detailed in the following.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 depicts a side view illustration of a schematic showing mechanical arrangement of portions of an embodiment of the invention.
FIG. 2 depicts a top view illustration of the schematic of FIG. 1 showing mechanical arrangement of portions of an embodiment of the invention.
FIG. 3 shows a block diagram for an embodiment of the invention illustrating relationships between various portions of the electrical/computer hardware for acquiring and processing x-ray detector signals and for activating selected air valves within an air ejector array responsive to the results of the processing.
FIG. 4 shows an example graph of processed x-ray transmission data measured at two different x-ray energy levels for various nonferrous metals derived from an automobile shredder.
FIG. 5 shows a logic flow diagram representative of a materials identification and sorting algorithm for an embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention uses analyses of x-ray absorptions in a material at differing energy levels in order to determine the relative atomic density (atomic number Z) of the material. X-ray absorption in a material is a function of the atomic density of the material and also a function of the energy of the incident x-rays. A given piece of material will absorb x-rays to differing degrees depending upon the energy of the incident x-rays. Materials of differing atomic numbers will absorb x-rays differently. For instance copper (Z=29) will absorb x-rays much more readily than will aluminum (Z=13). Also the absorption profile of a given piece of copper over a range of x-ray energies will be different than the absorption profile of a given piece of aluminum over that same range of energies. X-ray transmission through a material is given by the equation
N (t) =N 0 e −ηρ t
Where N (t) is the number of photons remaining from an initial N 0 photons after traveling through thickness t in a material of density ρ. The mass attenuation coefficient η is a property of the given material and has a dependence upon photon energy. The value ηρ is referred to as the mass absorption coefficient (μ) for a given material. Values of the coefficient μ have been established by researchers to high accuracy for most materials and these values are dependent upon the energy of incident x-ray photons. Values of μ/ρ (=η) for most materials can be found at the National Institute of Standards and Technology (NIST) internet website. The lists of values are extensive covering all stable elements for various values of photon energy (kev). The value of ρ for a given material is simply its density in gm/cm 3 and can be found in many textbooks and also at the NIST website. The ratio N (t) /N 0 is the transmittance of photons through a thickness t of material and is often given as a percentage, ie. the percentage of photons transmitted through the material.
The following table, by way of example, gives values of the mass absorption coefficient μ for aluminum and copper over a range of incident x-ray photon energies and the percentage of photons remaining after passing through 0.2 cm of material (% transmission).
Incident Photon Mass Absorption Energy (kev) Coefficient μ (cm −1 ) % Transmission Aluminum 100 0.46 91% 80 0.54 90% 60 0.75 86% 50 0.99 82% 40 1.53 74% 30 3.04 54% Copper 100 4.11 44% 80 6.84 26% 60 14.27 5.8% 50 23.41 0.93% 40 40.95 0.03% 30 97.84 <0.00%
Using the information in the table above we can illustrate how aluminum in this case can be differentiated from copper by comparing ratios of % Transmission (T E ) at two different photon energy levels. For instance:
Ratios: T 100 /T 50 =1.11 for aluminum, T 100 /T 50 =47.3 for copper
The ratio for copper is much higher than that for aluminum. Further, we find that for differing thicknesses of materials it is possible to distinguish between materials of differing Z value by comparing such ratios while correlating to levels of transmission of photon energy through the materials as is discussed in more detail later. This innovative analytical technique allows effectively differentiating between the materials independent of knowing or determining thickness of the materials as is further discussed in reference to FIG. 4 .
FIG. 1 shows a side view and FIG. 2 a top view of a schematic of mechanical arrangement of portions of a preferred embodiment of a materials sorting system of the present invention that incorporates a dual energy x-ray detector array 4 positioned below the surface of a conveyor belt 1 used for transporting materials samples 3 into and through a sensing region 4 s located on conveyor belt 1 between detector array 4 and x-ray tube 15 . Belt 1 moves in a direction as shown by arrow 2 in FIG. 1 and FIG. 2 . Detector arrays suitable for this use can be obtained from Elekon Industries, Torrance, Calif. X-ray tubes may be obtained from Lohmann X-ray, Leverkusan, Germany. Materials samples 3 may be a mixture of relatively high Z materials 11 (such as metals copper, iron, and zinc and their alloys—depicted by shaded samples) and relatively low Z materials 9 (such as metals magnesium and aluminum and their alloys—depicted by not shaded samples). The x-ray tube 15 is a broadband source that radiates a sheet of preferably collimated x-rays 16 across the width of conveyor belt 1 along the dual energy x-ray detector array 4 such that x-rays pass through sensing region 4 s and conveyor belt 1 prior to striking detectors 4 . Such a dual energy x-ray detector array 4 is well-known in the art, an example of which is described in detail in GE Medical Systems U.S. Pat. Nos. 6,266,390 and 6,519,315. As materials samples 3 pass through the sheet of x-rays in sensing region 4 s x-rays transmitted through them are detected by the dual energy x-ray detector array 4 at two different energy levels. The detection signals are transmitted to computer system 12 over electrical connections 13 and the signals analyzed by a software algorithm 40 ( FIG. 5 ) executing within computer system 12 to determine relative composition of samples 3 with respect to a preset relative composition level 35 ( FIG. 4 ), as will be discussed in more detail later. In the example shown computerized algorithm 40 processes measurements of transmission levels of x-rays through materials at two energy levels using data from detector array 4 and makes a classification of each material sample 3 as being a relatively low Z material 9 or as being a relatively high Z material 11 with respect to preset relative composition level 35 and selects either low Z materials 9 or high Z materials 11 for ejection from the stream. Downstream from the sensing region 4 s , located just off the discharge end of the conveyor belt 1 and positioned across the width of the trajectory paths 6 , 7 of materials discharged off the end of conveyor belt 1 , is an array of high speed air ejectors 5 , such as the L2 series supplied by Numatics, Highland, Mich., which are controlled by computer system 12 , responsive to the algorithm 40 computations, by signaling air ejectors controller 17 through connections 14 to selectively energize through connections 18 appropriate air ejectors within air ejectors array 5 to deflect by short air blasts 5 a selected materials from the flow. In the example shown relatively high Z metals 11 are selected for ejection along trajectories 7 into the metal group 1 bin 10 and relatively low Z metals 9 pass unejected along trajectories 6 into metal group 2 bin 8 . It is noted that the system can just as easily be configured by the user through a standard control interface (not shown) to eject low Z materials into group 1 bin 10 and let high Z materials pass unejected into group 2 bin 8 . It will be apparent to those skilled in the art that three or more bins could be utilized using multi-directional air ejectors or other sorting means. The sequence of sensing, selection, and ejection can happen simultaneously in multiple paths along the width of the conveyor belt 1 so that multiple metal samples 3 can be analyzed and sorted coincidentally as indicated in FIG. 2 .
FIG. 3 shows a block diagram for an embodiment of the invention illustrating relationships between various portions of the electrical/computer system for acquiring and processing x-ray detector signals and for activating selected air valves within air ejector array 5 responsive to the results of the processing. The dual energy detector array 4 in this embodiment includes within its circuitry the dual energy x-ray detectors 4 a and a data acquisition system (DAQ) with analog to digital (A/D) circuitry 4 b for acquiring analog signals from the detectors over connections 4 c and converting these signals to digital signals. The digital signals are transmitted over connections 13 a , which are part of the electrical connections 13 between computer system 12 and dual energy array 4 , to digital input/output (DIO) module 20 . For this data transfer the input function of module 20 is utilized. Internal to computer system 12 DIO module 20 passes the digital data to microprocessor system 21 . Microprocessor system 21 may be a single microprocessor or a system of multiple microprocessors linked together to share computational tasks to enable high speed data processing as is the case for this preferred embodiment. A suitable multiple microprocessor system is the Barcelona-HS available from Spectrum Signal Processing, Burnaby, Canada. Microprocessor 21 provides control signals to dual energy array 4 through serial controller 23 over electrical connection 13 b . Materials classification and sorting algorithm 40 ( FIG. 5 ), which is discussed in more detail later, executes within microprocessor system 21 processing digital data received from dual energy array 4 and utilizes computer memory 22 for storing data and accessing data during execution. According to results derived through executing of algorithm 40 microprocessor system 21 signals air ejectors controller 17 , for example a bank of solid state relays such as those supplied by Opto 22 , Temecula, Calif., through DIO module 24 to energize selected air ejectors within air ejector array 5 over connections 18 so to eject from the flow of materials 3 selected materials 11 according to computed relative composition as the materials are discharged off the discharge end of conveyor 1 . The user of the sorting system may chose through a standard control interface (not shown) for ejected materials 11 to be relatively high Z materials or relatively low Z materials, compared to preset relative composition level 35 (stored in memory 22 ) as determined by algorithm 40 .
The x-ray technology of the present invention measures changes in amount of x-ray transmission through an object as a function of energy. This technology can evaluate the entire object and looks through the entire object taking into consideration exterior and interior variations. The technology evaluates how the quantities of transmitted x-rays at various energy levels change as a function of the incident x-ray energy. One embodiment may be a multi-energy cadmium zinc telluride (CZT) pixel detection system arranged into a linear detector array of very small size is suitable to collect x-ray transmission information at each detector site and transmit it to an on-board computer system to collect data from multiple sensors simultaneously. Another embodiment may be an arrangement of multiple individual multi-energy detection systems such as those provided by Amptek, Bedford, Mass. Such systems could provide a greater number of energy bins. Multiple sub-systems could cover a wide conveyor belt. The data from the multi-detector array will provide multi-energy readings from each detector to provide an energy dispersive x-ray transmission profile of an object for assessing composition of a broad range of matter. Such a multi-energy CZT linear detector array having 32 CZT detectors at 0.5 mm pitch is available with supporting electronics from Nova R&D, Riverside, Calif. Each detector in the Nova R&D detection system can read and report x-ray transmission levels at up to five energy bands simultaneously at high rates of data acquisition and this capability is expected to expand to more energy bands as the technology is further developed. Further, the detectors have a spatial resolution of 0.02 inches per pixel in the array allowing detailed high resolution multi-energy profiling of x-ray transmission through an object under inspection. In effect one can build a high resolution multi-energy image of an object under inspection as the object is conveyed through the inspection region as well as simultaneously measuring the relative average atomic number of bits of matter within the image.
Such a system is functionally analogous to a line-scan camera commonly found in industrial inspection processes. Whereas a line-scan camera detects multiple “colors” within the visible spectrum, the system of the present invention detects “colors” within the x-ray spectrum. Thus, the system may be characterized as a multi-spectral, x-ray camera providing a much richer data set than the dual energy techniques described in more detail herein. This multi-energy data set allows expanded imaging and material identification capabilities as described in general terms below.
While the new system provides data that can be represented by an x-ray image, an intelligent interpretation of that image is essential to identification and sortation of material. The presence of any atomic element is manifest by spectral peaks (from fluorescence) or discontinuities (from transmission) that result from electron-state transitions unique to that element. Since these peaks or edges occur in spectrally narrow regions (on the order of eV), detection of an element only requires monitoring a small portion of the spectrum. Unfortunately, the absorption edges of “interesting” elements span a wide energy range, from less than 1 keV to more than 80 keV. Additionally, material morphology and composition, processing rates and environment, and sensor response renders peak or edge detection as the exclusive method of sorting a wide variety of materials impractical. Peaks or edges may be used to discriminate among a subset of elements, but it is thought that interrogating a material's spectrum over a shorter energy range (shorter than 1 keV→80 keV) will divulge information sufficient for recycling purposes although a range double that (up to 160 keV) could be useful. In particular, applying derivatives, tangential intersections and spectral correlation to the absorption curve of a material could provide adequate discrimination among categories of recyclables.
When compared to the simple discriminators of difference or ratio, the proposed operations are, in general, more susceptible to noise within the response curve of a material. Thus, to generate meaningful descriptors, mitigating all forms of “noise” is advantageous. Since in one embodiment the system of the present invention measures individual photons, the inherent noise from this method of detection is described by a Poisson distribution and can be reduced by collecting more photons. The nature of the CZT detectors in the Nova R&D linear array system limits the photon counting rate to approximately 50 million counts per second (MCount/Sec): the ensuing electrons further limit this rate to approximately 1 MCount/Sec. New systems under development could extend the counting rate by an order of magnitude (up to 500 MCount/Sec). Since sufficiently “smooth” curves may require thousands of counts per acquisition, noise reduction through increased photon counts can result in decreased processing rates.
A material's absorption curve could prove sufficient for identification and sortation. However, certainty during the identification process may be augmented by fluorescence information. When x-rays pass through a material, some x-rays with energies greater than the electron excitation energy of constituent elements are absorbed and re-emitted as fluoresced photons. This process of absorption and re-emission is characterized in the transmission spectrum as an “absorption edge” and a “fluorescence peak,” where the peak is always near, but at a slightly lower energy than the edge. In a traditional absorption curve, the fluorescent peak is negligible. However, as a detector is gradually removed from the primary path of x-ray transmission, the signal contribution from primary x-rays are reduced and the contribution from secondary x-rays, such as fluorescence and scatter, are increased. Understandably, fluorescence is considered a “surface” phenomenon, but perhaps this information could enhance identification under certain conditions.
FIG. 4 shows an example graph 30 of processed x-ray transmission data measured for two different x-ray energy levels through various pieces of nonferrous metals derived from an automobile shredder. X-axis 31 of the graph represents normalized values of percentage transmission of x-rays (ie. transmittance values) through each metal piece as measured by the high energy detectors (item 43 , FIG. 5 ) of array 4 . Y-axis 32 of the graph represents values of the ratio (item 46 , FIG. 5 ) of normalized values of percentage transmission of x-rays through each metal piece as measured by the high energy detectors of array 4 to the percentage transmission of x-rays through a material sample 3 as measured by the low energy detectors of array 4 . In graph 30 data points 34 for the various metal samples are plotted according to their X-axis and Y-axis values. Legend 33 identifies each type data point as being for a brass, copper, zinc, stainless steel, aluminum alloy, or aluminum sample. Brass, copper, zinc, and stainless steel are considered to be relatively high Z metals and are represented by shaded data points in graph 30 . Aluminum and aluminum alloys are considered to be relatively low Z metals and are represented by not shaded data points in graph 30 . As can be seen in graph 30 data points for relatively high Z metals generally fall into a region 36 which resides above a region 37 into which fall data points for relatively low Z metals. A discriminator curve 35 has been drawn through the graph separating high Z region 36 from low Z region 37 . This curve 35 in effect represents a preset relative composition level against which values ( 43 , 46 ) derived for a material sample can be compared to classify the sample as being either a relatively high Z material or as being a relatively low Z material. Other treatments of the x-ray transmission data can be utilized as well, for example locating paired logarithmic transmittance data points from the detectors in a two dimensional space with the logarithm of transmittance from the low energy detector being one axis of the space and the logarithm of transmittance from the high energy detector being the other axis. In this case a discriminator curve such as curve 35 may be found which will separate the two dimensional space into relatively high Z materials and relatively low Z materials independent of thickness of the materials. Those skilled in the art will recognize that there are numerous other methods of varying complexity for correlating data from the detectors so that regions of relative composition, such as high Z regions, low Z regions, and other Z regions can be reliably distinguished.
In an embodiment of the present invention a classification and sorting algorithm 40 , represented in FIG. 5 , utilizes the above described type of data interpretation to classify samples as being composed of relatively high Z materials or relatively low Z materials and effects sorting of the samples accordingly. For this example a material sample 3 enters the sensing region 4 s and the presence of the sample is detected by a drop in x-ray radiation received by the detectors beneath the sample at the detector array 4 . This drop in radiation results in a drop in signal level from the detectors 4 a . The measured drop in signal level is noted by microprocessor system 21 which is monitoring the signal levels and causes microprocessor system 21 to start 41 execution of identification and sorting algorithm 40 . During execution of algorithm 40 the value E H of a high energy sensor is read 42 and the value E L of a corresponding low energy sensor is read 44 . The values are normalized 43 and 45 , for instance by subtracting out pre-measured detector noise and then scaling the readings to the detector readings when no materials are in region 4 s over the detectors. These subtracting and scaling operations convert the sensor readings to transmittance values. Normalized value 43 , (transmittance of the high energy region photons) is then divided by normalized value 45 (transmittance of low energy region photons) to compute a ratio E R 46 of high energy transmittance to low energy transmittance. Ratio 46 is then correlated with normalized high energy transmittance 43 using a correlation function 47 which is electronically equivalent to plotting a data point ( 43 , 46 ) onto a graph such as that of FIG. 4 . Step 48 in the algorithm then computes whether correlated data ( 43 , 46 ) electronically lies within a relatively high Z region 36 or a relatively low Z region 37 . In the example shown, if the correlated data ( 43 , 46 ) electronically is in a high Z region 36 algorithm 40 returns YES determination 49 and the material is categorized as a high Z material 50 . In the example shown the algorithm continues along path 51 , calculates 52 position and timing information for arrival of sample 3 at the ejection array 5 needed to accurately energize downstream ejector mechanisms in array 5 and issues the necessary commands 53 at the right time to energize the appropriate ejectors to eject high Z material 50 from the flow 2 of materials 3 . In this case materials determined to be low Z materials 55 by algorithm 40 returning a NO determination 54 will not be ejected by ejection array 5 . Alternatively, the algorithm can be configured by the user through a standard user interface to the computer system 12 to not follow path 51 and to instead follow alternate path 56 so that materials that are determined to be low Z materials 55 are ejected by ejection array 5 and materials determined to be high Z materials 50 are not ejected by ejection array 5 . Those skilled in the art will recognize that other similar algorithms can be applied according to the method selected for treatment of the detector data.
All references, publications, and patents disclosed herein are expressly incorporated by reference.
For the convenience of the reader, the following is a listing of the reference numbers used in the figures:
1 . Conveyor belt 2 . Arrow showing flow of materials on conveyor belt 3 . Materials samples 4 . X-ray detector array 4 a . Dual x-ray detector 4 b . Data acquisition with A/D 4 c . Electrical connection 4 s . Sensing region on conveyor belt 1 5 . Air ejectors array 5 a . Air blast 6 . Trajectory corresponding to unejected sample 7 . Trajectory corresponding to ejected sample 8 . Group 2 bin (for unejected samples) 9 . Unejected metal sample 10 . Group 1 bin (for ejected samples) 11 . Selected materials for ejection by air ejectors 12 . Computer system 13 . Electrical connection 13 a . Electrical connection 13 b . Electrical connection 14 . Electrical connection 15 . X-ray tube 16 . Sheet of collimated x-rays 17 . Air ejectors controller 18 . Electrical connection 20 . Digital input/output (DIO) module 21 . Microprocessor system 22 . Computer memory 23 . Serial controller 24 . Digital input/output (DIO) module 30 . Graph 31 . X-axis of graph 32 . Y-axis of graph 33 . Legend to graph 34 . Data points for various metal samples 35 . Discriminator curve 36 . High Z region of graph 37 . Low Z region of graph 40 . Identification and sorting algorithm 41 . Start of execution of algorithm 42 . High energy sensor is read 43 . Normalizing value of 42 44 . Low energy sensor is read 45 . Normalizing value of 44 46 . Computing ratio of normalized value 43 to normalized value 45 47 . Correlation function 48 . Determining step in algorithm 40 49 . YES determination in algorithm 40 50 . High Z material 51 . Path in algorithm 40 52 . Calculation step in algorithm 40 53 . Command step in algorithm 40 54 . NO determination in algorithm 40 55 . Low Z material 56 . Alternate path in algorithm 40
Thus, it is seen that the system and method of the present invention readily achieves the ends and advantages mentioned as well as those inherent therein. While certain preferred embodiments of the invention have been illustrated and described for purposes of the present disclosure, numerous changes in the arrangement and construction of parts may be made by those skilled in the art, which changes are encompassed within the scope and spirit of the present invention as defined by the following claims. | Disclosed herein is a metal sorting device including an X-ray tube, a dual energy detector array, a microprocessor, and an air ejector array. The device senses the presence of samples in the x-ray sensing region and initiates identifying and sorting the samples. After identifying and classifying the category of a sample, at a specific time, the device activates an array of air ejectors located at specific positions in order to place the sample in the proper collection bin. | 1 |
FIELD AND BACKGROUND OF THE INVENTION
[0001] The present invention relates to a method and system of fire control and, more particularly, to a fire control method and system for a tank gun, or the like, that is mounted on a platform such as a tank turret.
[0002] Tank fire control includes a series of operations, the propose of which is to aim the tank's gun so as to hit the target. If the first shot does not hit the target, adjustments must be made in the gun's aim in the quickest and most accurate way. Wile many efforts have been made in the art to facilitate hitting the target with the first shot, no efficient process and/or apparatus is at present available for permitting a single tank to adjust its fire when the first shot has failed to hit. Fire adjustments are difficult to effect by a single tank for many reasons, including the shocks due to the firing, the difficulty of observing the impact of the projectiles if they do not produce an explosion or, even if they do produce an explosion, because of the presence of dust, the period of time that must pass between the observation of the projectile impact and the firing of the next projectile with an adjusted aim, and so forth. As a result, fire control must be ended to a station separate from the tank or at least requires the collaboration of at least one other tank, and even these means do not provide as prompt an adjustment of the aim as would be desirable. This is very disadvantageous from the viewpoint of the operational autonomy and of the firing efficiency of the tanks.
[0003] There is thus a widely recognized need for, and it would be highly advantageous to have, a method and system of tank fire control that would enable the crew of a tank to correct the aim of the tank's gun autonomously.
SUMMARY OF THE INVENTION
[0004] It is a purpose of this invention to provide a fire control system for a tank's gun that is entirely autonomous and does not require the collaboration of a separate fire control station or of another tank.
[0005] It is another purpose of the invention to provide such a system that permits rapid and accurate adjustment of the gun's aim on the part of the tank's crew.
[0006] It is a further purpose of the invention to provide such a system that permits automatic adjustment of the gun's aim on the part of the gun's firing system.
[0007] It is a still further propose of the invention to provide such a system that does not require visual observation of the projectile's impact. Indeed, the present invention can initiate correction of the aim of the gun even before projectile impact.
[0008] It is a still further purpose of the invention to provide such a system that is not adversely affected by the firing shocks and by the presence of dust.
[0009] Therefore, according to the present invention there is provided a method of aiming a gun that is mounted on a platform and that has fired a projectile at a target, the firing of the gun casing the platform to vibrate, including the steps of: (a) tracking the projectile and the target, using a tracking device, at least a portion whereof is operationally connected to the platform; and (b) inferring an aim error vector from the tracking.
[0010] Furthermore, according to the present invention there is provided A fire control system for a gun that is mounted on a platform and that fires a projectile at a target, including: (a) an antenna that is operationally connected to the platform; (b) a transmitter for transmitting projectile-tracking RF pulses and target-tracking RF pulses via the antenna; (c) a receiver for receiving echoes of the RF pulses via the antenna; and (d) a signal processor for receiving signals, representative of the echoes, from the receiver and transforming the signals into measurement vectors for the projectile and the target.
[0011] The term “trajectory” is used herein to refer to the position and velocity of an object, specifically, of the projectile or of the target, as a function of time. Typically, the trajectory of the projectile is a ballistic trajectory, and the trajectory of the target is whatever motion, if any, the target executes. In the special case of a stationary target, the target trajectory is simply the fixed position of the target.
[0012] The scope of the present invention includes methods and systems of autonomous fire control for any platform-mounted gun. Nevertheless, the focus of the description herein is on autonomous fire control for a tank, in which the platform on which the gun is mounted is the turret of the tank. According to the present invention, at least a portion of a tracking device, for example, the antenna of a radar tacking system, is mounted on the platform. After the gun is fired at the target, and preferably after the vibration (shock) of firing has substantially stopped, the tracking device is used to track both the projectile, in flight, and the target. This tracking allows the determination, in real time, of the trajectory of the projectile and the deviation of that trajectory from the trajectory of the target. An aim error vector, that includes an azimuth error and an elevation error, is inferred from this deviation, and the gun is moved to correct its aim accordingly.
[0013] Preferably, the portion of the tracking device, that is mounted on the platform, is mounted rigidly thereon.
[0014] Preferably, the tracking device is based on radar, the antenna whereof is rigidly mounted on the platform. Most preferably, the antenna is a two-way monopulse antenna. A transmitter transmits, via the antenna, alternately, Doppler RF pulses for tracking the projectile and linear frequency modulated (chirp) pulses for tracking the target. A receiver receives echoes of the pulses via the antenna and provides signals representative of the echoes, typically Σ signals, Δ Az signals and Δ El signals, to a signal processor. The signal processor uses a CFAR method to discriminate echoes from the projectile and the target from clutter echoes, and transforms the signals corresponding to projectile echoes and target echoes to measurement vectors of the projectile's instantaneous position and velocity and of the target's instantaneous position and velocity. These measurement vectors are input to a post-processor, in which a Kalman filter uses the measurement vectors to update corresponding state vectors. The state vector of the projectile defines the projectile's trajectory. The state vector of the target defines the target's trajectory. The post-processor computes the amount by which the projectile's trajectory misses the target's trajectory and infers therefrom the aim error vector.
[0015] Preferably, a synchronizer coordinates the transmission of the RF pulses and the reception of the echoes thereof, and also coordinates the alternation between projectile-tracking pulses and target-tracking pulses.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The invention is herein described, by way of example only, with reference to the accompanying drawings, wherein:
[0017] The sole FIGURE is a schematic depiction of a system of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0018] The present invention is of a fire control method and system which can be used to correct the aim of a platform-mounted gun, that has fired a projectile at a target, while the projectile is in flight. Specifically, the present invention can be used to adjust the aim of a tank gun autonomously.
[0019] The principles and operation of fire control according to the present invention may be better understood with reference to the drawings and the accompanying description.
[0020] Referring now to the drawings, the sole Figure is a schematic illustration of a system of the present invention, as applied to fire control for the firing of a gun 14 mounted an a turret 12 of a tank 10 .
[0021] Also mounted on turret 12 is a two-way monopulse antenna 20 . Preferably, antenna 20 is mounted rigidly on turret 12 . As used herein, the team “mounted rigidly” means that antenna 20 may be rigidly attached to turret 12 , so that antenna 20 points in a direction determined exclusively by the orientation in space of turret 12 ; but also means that antenna 20 may alternatively be mechanically steerable by virtue of being mounted on a mount, such as au altazimuth mount 18 , that in turn is rigidly attached to turret 12 . Preferably, if antenna 20 is rigidly attached to turret 12 , then the field of view of antenna 20 is at least 15 mrad in azimuth and at least 32 mrad in elevation.
[0022] A transmitter 22 generates radio frequency (RF) pulses that are launched by antenna 20 towards the projectile and towards the target. Specifically, transmitter 22 alternates between generating Doppler pulses, that are used to track the projectile, and linear frequency modulated (chirp) pulses, that are used to track the target. Preferably, the RF pulses are in the Ka band. Echoes of the RF pulses are received, via antenna 20 , by a receiver 24 . The received echoes are downconverted in frequency and, in the case of the received chirp echoes, also dechirped. The echoes thus received are passed by receiver 24 to a signal processor 28 as analog signals, specifically, Σ, Δ Az and Δ El signals. Signal processor 28 digitizes the analog signals and processes the digitized signals by standard methods. In particular, the signals preferably are processed using Fast Fourier Transforms (FFTs) of appropriate lengths. The FFT length for processing the projectile-echo signals depends on the Doppler pulse repetition frequency and on the required Doppler resolution, which is on the order of one meter per second. Typically, this length is in the hundreds (256 or 512). The FFT length for processing the target echo signals also typically is in the hundreds. A constant false alarm rate (CFAR) method is used to discriminate projectile echoes and target echoes from clutter echoes.
[0023] The output of the processing in signal processor 28 is, for each projectile echo, a measurement vector M P whose components are projectile range, projectile azimuth, projectile elevation, and three components (range, azimuth, elevation) of the projectile velocity vector; and, for each target echo, a measurement vector M T whose components are target range, target azimuth, target elevation, and, optionally, three components (range, azimuth and elevation) of the target velocity vector. Projectile range is determined from the round-trip travel time of the projectile echo. Projectile azimuth and elevation are determined from appropriate processing of the corresponding Σ, Δ Az and Δ El signals. The range component of the projectile velocity vector is determined from the Doppler shift of the projectile echo. The azimuth and elevation components of the projectile velocity vector are determined from the numerical time derivative of the azimuth and elevation components of successive projectile echoes. Target range is determined from the round-trip travel time of the target echo. Target azimuth and elevation are determined from appropriate processing of the corresponding Σ, Δ Az and Δ El signals. Optionally, the three components of the target velocity vector are determined from the numerical time derivative of the range, azimuth and elevation components of successive target echoes.
[0024] A synchronizer 26 coordinates the activities of transmitter 22 and receiver 24 . Specifically, for each projectile-tracking pulse or target-tracking pulse launched by transmitter 22 , synchronizer 26 activates receiver 24 only in a corresponding time gate during which a corresponding echo from the projectile or form the target is expected to arrive at antenna 20 . In addition, synchronizer 26 causes transmitter 22 to alternate between transmitting projectile-tracking pulses (Doppler) and target-tracking pulses (chirp). Preferably, the projectile and the target are tracked almost concurrently, with the time interval between the transmission of a projectile-tracking pause and a target-tracking pulse being on the order of a few milliseconds. Preferably, successive sightings of the projectile and of the target are effected at a rate of about 100 Hz (100 times per second). The total number of sightings depends on the type of projectile and on the type of target, but preferably is at least about 100.
[0025] Tracking of the projectile and of the target is not initiated until the shock of the firing of gun 14 has substantially dissipated. Typically, this time interval between the fixing of gun 14 and the initiation of tacking is several tenths of a second.
[0026] Signal processor 26 passes the measurement vectors M P and M T to a post-processor 30 . Post-processor 30 uses these measurement vectors as input to a predictor-corrector algorithm for updating state vectors that represent estimates of the true positions and velocities of the projectile and of the target. The preferred predictor-corrector algorithm is a Kalman filter. The components of the state vectors correspond to the components of the measurement vectors: the components of the projectile state vector are the projectile range, the projectile azimuth, the projectile elevation, and time derivatives thereof (i.e., the projectile velocity vector); and the components of the target state vector are the target range, the target azimuth, the target elevation, and, optionally, time derivatives thereof (i.e., the target velocity vector). The state vectors are initialized when gun 14 is fired. The initial position of the projectile is at gun 14 . The initial velocity of the projectile is the muzzle velocity of the projectile. The illustrated analog components (antenna 20 , transmitter 22 , receiver 24 ) also serve as components of a target acquisition radar system (not shown) that is used to acquire the target and aim gun 14 at the target before gun 14 is fired; and the initial state vector of the target is obtained from this target acquisition system.
[0027] As noted above, the state vectors of the projectile and of the target define the trajectories of the projectile and of the target. Based on these trajectories, post-processor 30 computes an azimuth error and an elevation error for gun 14 . The azimuth error is simply the difference between the azimuth of the projectile trajectory, projected out to the range of the target, and the azimuth of the target. The elevation error is the difference between the actual elevation of the gun and the elevation that would be required for the two trajectories to intersect if there were no azimuth error. This elevation error is computed by post-processor 30 using well-known ballistic equations. The azimuth error and the elevation error are the components of an aim error vector for gun 14 . Note that, even before the projectile impacts, the ballistic equations may be used to predict the remaining trajectory of the projectile. Meanwhile, the fixture behavior (until projectile impact) of the target may be predicted on the basis of the observed behavior of the target. Therefore, the aim error vector may be computed while the projectile is still in flight.
[0028] Post-processor 30 passes the aim error vector along to the crew of tank 10 . The crew of tank 10 corrects the aim of gun 14 in accordance with the aim error vector. Alternatively, if tank 10 is equipped with an automatic system for aiming gun 14 , post-processor 30 sends the aim error vector to the automatic aiming system, which automatically corrects the aim of gun 14 .
[0029] While the invention has been described with respect to a limited number of embodiments, it will be appreciated that many variations, modifications and other applications of the invention may be made. | A method of aiming a gun ( 14 ) that is mounted on a platform ( 12 ) and that has fired projectile at a target, the firing of the gun ( 14 ) causing the platform ( 12 ) to vibrato. The method includes tracking the projectile and the target, using a tracking device ( 20 ) and inferring an aim error vector from the tracking. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS/INCORPORATION BY REFERENCE
This application makes reference to, claims priority to, and claims the benefit of U.S. Provisional Application Ser. No. 60/828,566, filed on Oct. 6, 2006, which is hereby incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
Certain embodiments of the invention relate to secure systems. More specifically, certain embodiments of the invention relate to a method and system for version control in a reprogrammable security system.
BACKGROUND OF THE INVENTION
Various security mechanisms may be implemented to protect reprogrammable systems deployed in the field such as set top boxes in a video distribution system. Occasionally, entry points to restricted-access functionality on such systems may be neglected by resident security code and/or circuitry. Unauthorized users may discover ways to navigate around existing security obstacles and gain prohibited access. In a reprogrammable security system, security software may be updated with subsequent versions of code that correct errors found in prior versions. Security code updates may be distributed by a control center and downloaded in the field. Further access by unauthorized users may require new approaches to the problem.
It may be difficult for an unauthorized user to gain restricted access to a device in the field by making modifications to resident security code. Such an attempt would require extensive knowledge and skill on the part of the user due to cryptographic applications. An alternate means may be to make a copy of a prior version of security code whose design is vulnerable to breach, and download it onto the device over a subsequent version of improved code. The system may perceive the copy to be a properly authorized unit of code and may accept it readily into the system. With the prior version of code in place, the unauthorized user may again gain access using the original method to circumvent existing security obstacles. New techniques for securing reprogrammable systems may be needed to prevent future incursions.
Further limitations and disadvantages of conventional and traditional approaches will become apparent to one of skill in the art, through comparison of such systems with the present invention as set forth in the remainder of the present application with reference to the drawings.
BRIEF SUMMARY OF THE INVENTION
A system and/or method for version control in a reprogrammable security system, substantially as shown in and/or described in connection with at least one of the figures, as set forth more completely in the claims.
Various advantages, aspects and novel features of the present invention, as well as details of an illustrated embodiment thereof, will be more fully understood from the following description and drawings.
BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS
FIG. 1A is a block diagram of an exemplary reprogrammable security system that may utilize version control, in accordance with an embodiment of the invention.
FIG. 1B is a block diagram that illustrates an exemplary reprogrammable security system that enables version control, in accordance with an embodiment of the invention.
FIG. 2A is a flow diagram illustrating exemplary steps for version control in a reprogrammable security system, in accordance with an embodiment of the invention.
FIG. 2B is a continuation of the flow diagram in FIG. 2A , illustrating exemplary steps for version control in a reprogrammable security system, in accordance with an embodiment of the invention.
FIG. 2C is a continuation of the flow diagram in FIG. 2B , illustrating exemplary steps for version control in a reprogrammable security system, in accordance with an embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
Certain aspects of the invention may be found in a method and system for version control in a reprogrammable security system. Aspects of the invention may comprise a reprogrammable security processor that may be communicatively coupled with an external source of command and control. The security processor and the external source of command and control may enable detection of an invalid version of code resident in a security processor memory. The invalid version of code may for example, be a prior version of code that is copied and downloaded over a subsequent version of code. The security processor may utilize historical records of versions of downloaded code from a plurality sources to detect the resident copy of the prior version of code. The prior version of code may be deemed an invalid version of code and its presence may be considered a security breach. The security processor may take action to avoid execution of the invalid version of code.
FIG. 1A is a block diagram of an exemplary communications system that may utilize a reprogrammable security system with version control, in accordance with an embodiment of the invention. Referring to FIG. 1A , there is shown a video distribution system that may comprise a command and control head-end 150 , a communications satellite 152 , a satellite communications link 154 , a communications distribution network, a plurality of set top boxes ( 1 ) 158 through (N) 160 , television units 162 and 164 .
The command and control head-end 150 may comprise suitable circuitry, logic and/or code and may be adapted to distribute video and control signals via the communications distribution network 156 to a plurality of set top boxes ( 1 ) 158 through (N) 160 . The command and control head-end 150 may distribute code utilized for security operations within the plurality of set top boxes ( 1 ) 158 through (N) 160 .
The communications distribution network 156 may comprise suitable circuitry, logic and/or code and may be adapted to provide links between various originating and terminating points for transmission of signals. The communications distribution network 156 may transport signals carrying code utilized for security operations within the plurality of set top boxes ( 1 ) 158 through (N) 160 from the command and control head-end 150 .
The communications satellite 152 and corresponding satellite communications link 154 may comprise suitable circuitry, logic and/or code and may be adapted to provide uplink and downlink wireless transmissions for the distribution network 156 . The communications satellite 152 uplink and downlink wireless transmissions may transport signals carrying code utilized for security operations within the plurality of set top boxes ( 1 ) 158 through (N) 160 from the command and control head-end 150 .
The plurality of set top boxes ( 1 ) 158 through (N) 160 may comprise suitable circuitry, logic and/or code and may be adapted to receive and transmit signals from/to the command and control head-end 150 . The plurality of set top boxes ( 1 ) 158 through (N) 160 may comprise suitable circuitry, logic and/or code for processing, storing and communicating information within the set top box. The plurality of set top boxes ( 1 ) 158 through (N) 160 may comprise a reprogrammable security system that may enable security operations for protected functionality therein. The plurality of set top boxes ( 1 ) 158 through (N) 160 may be communicatively coupled with the distribution network 156 and corresponding television units shown as 162 and 164 .
A plurality of television units shown as 162 and 164 are communicatively coupled with corresponding set top boxes. Television units receive and display decrypted signals from the set top boxes.
In operation, new versions of security processor code may be distributed by the command and control head-end 150 and transported via communications signals to the plurality of set top boxes ( 1 ) 158 through (N) 160 via one or more of the communications satellite 152 , the satellite communications link 154 , and the communications distribution network 156 . The plurality of set top boxes ( 1 ) 158 through (N) 160 may download the code and perform security operations according to various embodiments of the invention.
FIG. 1B is a block diagram that illustrates an exemplary reprogrammable security processor that enables detection of a prior version of code, in accordance with an embodiment of the invention. Referring to FIG. 1 , there is shown a reprogrammable security processor 100 that may comprise an external flash memory 102 , a code loading unit 104 , a latch memory 106 , a bootable read only memory (ROM) 108 , a one time programmable (OTP) memory 110 , a compare unit 112 , an external interface unit 114 , a command parser 116 , and a memory 118 .
The external flash memory 102 may comprise suitable storage for security processor code. The version of code resident within flash memory 102 may be identified by an embedded version identifier that may be positioned at a plurality of pre-determined locations within the code. In addition, the security processor code may be encrypted such that the version number may not be apparent to an outside observer and thus not subject to change. The external flash memory 102 may be communicatively coupled to the code loading unit 104 .
The code loading unit 104 may comprise suitable circuitry, logic and/or code and may be adapted to load and decrypt the code resident in external flash memory 102 and extract the resident code version identifier embedded within the plurality of pre-determined locations. The code loading unit 104 may be adapted to exchange information with the boot ROM 108 and the latch memory 106 .
The latch memory 106 may comprise storage for the version identifier embedded in the code resident in external flash memory 102 . The resident code version identifier may be extracted and latched in the latch memory 106 . Logic around the latch memory may check to see that the plurality of code version numbers embedded in the code all have the same value, thereby preventing a single “lucky guess” by a hacker trying to modify said version number. The latch memory 106 may be communicatively coupled with the code loading unit 104 and the compare unit 112 .
The boot ROM 108 may comprise suitable circuitry, logic and/or code to convert a bit in the OTP 110 from zero to one. The boot ROM 108 may be communicatively coupled with the code loading unit 104 and the OTP 110 .
The OTP 110 may comprise suitable storage for an OTP version identifier wherein the OTP version identifier may be a binary number initialized with zeros and may be increased in value to match a subsequent code version identifier by changing bits from zero to one but may not be changed to represent a prior code version identifier by reversing the bit value from one to zero. The OTP 110 may be communicatively coupled with the boot ROM 108 and the compare unit 112 .
The compare unit 112 may be communicatively coupled with the latch memory 106 , the OTP 110 and the memory 118 and may contain suitable circuitry, logic and/or code to compare version identifiers from a plurality of memory units.
The external interface unit 114 may be communicatively coupled with one or more external sources of code and commands for example a command and control head-end. The external interface unit 114 may comprise a decryption unit. The external interface 114 may receive streams of data from the one or more external sources of code and commands that may contain an expected resident code version identifier. The expected resident code version identifier may indicate which version of security processor code the reprogrammable security system expects to be resident in the flash memory 102 of security processor 100 .
The command parser 116 may be communicatively coupled with the external interface unit 114 and the memory 118 . The command parser 116 may contain suitable circuitry, logic and/or code to parse the expected resident code version identifier from the received streams of data from the one or more external sources of code and commands.
The memory 118 may be communicatively coupled with the command parser and the compare unit 112 and may contain suitable storage for the expected resident code version identifier.
In operation, security processor code may be downloaded into the external flash memory 102 and may comprise a corresponding version identifier embedded within a plurality of pre-determined locations. Two or more instances of the corresponding version identifier embedded within a plurality of pre-determined locations may be extracted and compared with each other. If any of the two or more instances of the embedded corresponding version identifiers do not match, the security processor 100 may enter a state of security breach.
The corresponding version identifier from the code resident in external flash memory 102 may be latched in latch memory 106 . The latched resident code version identifier may be compared with the OTP version identifier in OTP 110 . When the latched resident code version identifier represents a version of code subsequent to the OTP version identifier, the OTP version identifier may be increased to match the latched resident code version identifier. When the resident code version identifier represents a version of code prior to the OTP version identifier, the security processor 100 may consider this a breach in security and may proceed with operations accordingly; for example, the security processor 100 may report a security fault, may halt operations or may request a software update. Exemplary code version identifiers may comprise alphabetic, numeric, alphanumeric characters, and/or other codes.
The external interface unit 114 may receive streams of data comprising commands which may or may not be embedded in video, audio or data. These commands may have an expected resident code version identifier. The external interface 114 may decrypt the incoming data streams. The command parser 116 may receive the streams of data from the external interface 114 , may parse the expected resident code version identifier from the received streams of data and may store the expected resident code version identifier in memory 118 . The security processor 100 may compare the received expected resident code version identifier with one or more of the latched resident code version identifier and the OTP version identifier. When the resident code version identifier represents a version of code prior to the received expected resident code version identifier, the security processor 100 may process a breach in security and may proceed accordingly; for example, the security processor 100 may request a software update, may report a security fault, and may halt operations.
FIG. 2A is a flow chart illustrating exemplary steps for version control in a reprogrammable security system, in accordance with an embodiment of the invention. Referring to FIG. 2A , step 200 refers to the beginning of security operations on a reprogrammable security processor 100 shown in FIG. 1B . In step 202 , a one time programmable (OTP) version identifier in OTP 110 may initially contain zeros. In an exemplary embodiment of the invention, the OTP version identifier may be a binary number that may be increased to match a latched resident code version identifier by changing bits from zero to one but not from one to zero. Other methods of tracking the code version may be utilized without departing from the scope of the invention,
Notwithstanding, in step 204 , an external source of code and commands, for example a head-end, may send code to a set top box wherein a corresponding code version identifier may be embedded within the code in a plurality of pre-determined locations The embedded corresponding code version identifier may be encrypted along with the code. In step 206 , the received code may be stored in an external flash memory 102 . In step 208 , upon reset of the set top box, the security processor 100 may load the resident code from the external flash memory via the code loading unit 104 , extract and decrypt the corresponding code version identifier from the plurality of pre-determined locations within the resident code and may latch the resident code version identifiers in latch memory 106 .
In step 210 , the security processor 100 may compare two or more of the extracted instances of the resident code version identifier to each other. In step 212 , if the extracted resident code version identifiers match each other, the process may proceed to step 214 . In step 212 , If the extracted resident code version identifiers do not match each other, this outcome may be treated as a breach in security wherein for example, one or more of the following measures may be taken: the security processor 100 may reject the resident code and prevent execution of the resident code, a security fault may be reported to the head-end, the security processor 100 may download a subsequent version of code, the security processor 100 may disable one or more applications in the system.
FIG. 2B is a flow chart illustrating exemplary steps for version control in a reprogrammable security system, in accordance with an embodiment of the invention. Referring to FIG. 2B , step 214 is a continuation directive from the flow chart in FIG. 2A . In step 218 , the security processor 100 may compare the latched resident code version identifier to the OTP version identifier. In step 220 , if the latched resident code version identifier is equal to the OTP version identifier, the process may proceed to step 222 . In step 222 , the resident code may be accepted and operations may proceed to step 224 without intervention. In step 220 , if the latched resident code version identifier does not equal the OTP version identifier, the process may proceed to step 226 . In step 226 , if the latched resident code version identifier is greater than the OTP version identifier, the process may proceed to step 228 . In step 228 , the OTP version identifier may be increased to match the latched resident code version identifier and the process may proceed to step 222 . In step 226 , if the latched resident code version identifier is less than the OTP version identifier the process may proceed to step 230 . In step 230 , the security processor 100 may treat the outcome of step 226 as a breach in security wherein, for example, one or more of the following measures may be taken: the security processor 100 may reject the resident code and prevent execution of the resident code, a security fault may be reported to the head-end, the security processor may download a subsequent version of code, the security processor 100 may disable one or more applications in the system.
FIG. 2C is a flow chart illustrating exemplary steps for version control in a reprogrammable security system in accordance with an embodiment of the invention. Referring to FIG. 2C , step 224 is a continuation directive from the flow chart in FIG. 2B . In step 232 , streams of information which may be CA encrypted may be sent from the head-end to the security processor. The streams of information may comprise commands and an expected resident code version identifier for the security processor. A digest for verifying the received expected resident code version identifier may be embedded within the streams of information as well. In step 234 , the incoming streams of information may be received by an external interface unit 114 , decrypted and sent to a command parser 116 . The command parser 116 may parse the commands and expected resident code version identifier from the streams of information and store the expected resident code version identifier in memory 118 . In step 236 , the expected resident code version identifier may be compared with the latched resident code version identifier. The expected resident code version identifier may be compared with the OTP version identifier. In step 238 , if the expected resident code version identifier matches the latched resident code version identifier and the OTP version identifier, operations may proceed to step 240 .
In step 240 , the security processor 100 may determine that the resident version of code is secure and operations may continue to step 242 without taking intervening action. In step 238 , if the expected resident code version identifier does not match the latched resident code version identifier and/or the OTP version identifier, operations may proceed to step 244 . In step 244 , the security processor 100 may treat the outcome of step 238 as a breach in security wherein, for example, one or more of the following measures may be taken: the security processor 100 may reject the resident code and prevent execution of the resident code, a security fault may be reported to the head-end, the security processor 100 may download a subsequent version of code, the security processor may disable one or more applications in the system.
The method and system illustrated in FIG. 1B , enables version control in a reprogrammable security system and may protect against a breach of security. The breach of security may occur when an unauthorized user attempts to download a copy of a prior version of code, containing security flaws, over a subsequent version of code. The prior version of code may be detected by comparing historical code version identifiers from a plurality of records. For example, a one time programmable (OTP) memory 110 may contain a binary number that serves as a code version identifier. The OTP version identifier may be changed to represent subsequent versions of downloaded code but may not be changed in the direction of prior versions of code.
The version control method may comprise downloading into flash memory 102 , code wherein a corresponding code version identifier is embedded within a plurality of locations. Two or more instances of the embedded corresponding version identifiers may be extracted from the code by the code loading logic 104 and may be compared with each other. If any of the two or more instances of the embedded corresponding version identifiers do not match, the security processor 100 may detect a security breach. The security processor 100 may intervene with one or more of the following actions: reject the code resident in flash memory 102 and prevent execution of the code, report a security fault to the head-end, download a subsequent version of code and disable one or more applications in the system.
The corresponding version identifier may be latched in latch memory 106 to represent the version of code resident in flash memory 102 . The latched resident code version identifier and the OTP version identifier stored in OTP 110 may be compared within the compare unit 112 . If the latched resident code version identifier represents a version subsequent to the OTP version identifier, the OTP version identifier in OTP 110 may be increased to match the latched resident code version identifier. When the latched resident code version identifier and the OTP version identifier represent the same version of security processor code, no intervening action may be required. If the latched resident code version identifier represents a version of security processor code prior to the OTP version identifier, the security processor 100 may detect that a security breach has occurred. The security processor 100 may intervene with one or more of the following actions: reject the code resident in flash memory 102 and prevent execution of the code, report a security fault to the head-end, download a subsequent version of code and disable one or more applications in the system.
In another aspect of the invention, the external interface unit 114 may receive streams of information from the head-end comprising commands and a version identifier representing the version of code it expects to be resident on the security processor 100 . The security processor 100 may utilize the expected resident code version identifier to foil attempts at unauthorized access wherein an unauthorized user may have prevented an increase in the OTP version identifier when a new version of code may have been downloaded, thus enabling the unauthorized user to download an earlier version of code that matches an old OTP version identifier. In this regard, the head-end may send the expected resident code version identifier independent of any downloaded code and the old OTP version identifier may be detected.
Accordingly, the expected resident code version identifier may be parsed from the received streams of information by the command parser 116 and stored in the memory 118 . The expected resident code version identifier may be compared in the compare unit 112 with one or more of the latched resident code version identifier from latch memory 106 and the OTP version identifier from OTP 110 . If the compared identifiers represent the same version of security processor code, no intervening action is required. If the compared identifiers represent different versions of security processor code, the security processor 100 may detect a security breach. The security processor 100 may intervene with one or more of the following actions: reject the code resident in flash memory 102 and prevent execution of the code, report a security fault to the head-end, download a subsequent version of code and disable one or more applications in the system.
Aspects of the invention may be found in a method and system for detecting in a reprogrammable security system, instances when a prior version of code is copied over a subsequent version of code, and for controlling operations of the security system based on the detection as is shown in FIG. 1B block 100 . In this regard, each of the prior version of code and the subsequent version of code may comprise a corresponding unique code version identifier embedded therein. Additionally, the corresponding unique code version identifier for each of the prior version of code and subsequent version of code may be embedded in a plurality of locations therein as shown in block 102 of FIG. 1 . The corresponding unique code version identifier for each prior version of code and subsequent version of code may be encrypted within corresponding ones of the prior version of code and the subsequent version of code. Also, two or more instances of unique code version identifier for corresponding ones of prior version of code and subsequent version of code may be compared with each other. Based on the comparison, a security breach may be detected when any of the two or more instances of unique code version identifiers do not match.
The corresponding unique code version identifier for corresponding ones of the prior version of code and the subsequent version of code may be latched in memory block 106 . In this regard, the latched corresponding unique code version identifier stored in memory 106 and a stored one time programmable (OTP) unique code version identifier that corresponds to the prior version of code or the subsequent version of code stored in block 110 , may be compared within the comparator block 112 . Accordingly, the OTP unique code version identifier stored in block 110 may be changed to match the corresponding unique code version identifier latched in block 106 when the latched corresponding unique code version identifier indicates a subsequent version of code. If the result of the comparison shows that the stored OTP unique version identifier indicates a subsequent version of code, a security breach may be detected.
Within compare block 112 , one or more of the stored OTP unique code version identifier from block 110 and the latched corresponding unique code version identifier from block 106 , may be compared with a system reference code version identifier from memory 118 . As a result of the comparison, a security breach may be detected when the system reference code version identifier indicates a subsequent version of code.
Certain embodiments of the invention may comprise a machine-readable storage having stored thereon, a computer program having at least one code section for version control in a reprogrammable security system, the at least one code section being executable by a machine for causing the machine to perform one or more of the steps described herein.
Accordingly, aspects of the invention may be realized in hardware, software, firmware or a combination thereof. The invention may be realized in a centralized fashion in at least one computer system or in a distributed fashion where different elements are spread across several interconnected computer systems. Any kind of computer system or other apparatus adapted for carrying out the methods described herein is suited. A typical combination of hardware, software and firmware may be a general-purpose computer system with a computer program that, when being loaded and executed, controls the computer system such that it carries out the methods described herein.
One embodiment of the present invention may be implemented as a board level product, as a single chip, application specific integrated circuit (ASIC), or with varying levels integrated on a single chip with other portions of the system as separate components. The degree of integration of the system will primarily be determined by speed and cost considerations. Because of the sophisticated nature of modern processors, it is possible to utilize a commercially available processor, which may be implemented external to an ASIC implementation of the present system. Alternatively, if the processor is available as an ASIC core or logic block, then the commercially available processor may be implemented as part of an ASIC device with various functions implemented as firmware.
The present invention may also be embedded in a computer program product, which comprises all the features enabling the implementation of the methods described herein, and which when loaded in a computer system is able to carry out these methods. Computer program in the present context may mean, for example, any expression, in any language, code or notation, of a set of instructions intended to cause a system having an information processing capability to perform a particular function either directly or after either or both of the following: a) conversion to another language, code or notation; b) reproduction in a different material form. However, other meanings of computer program within the understanding of those skilled in the art are also contemplated by the present invention.
While the invention has been described with reference to certain embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the scope of the present invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the present invention without departing from its scope. Therefore, it is intended that the present invention not be limited to the particular embodiments disclosed, but that the present invention will include all embodiments falling within the scope of the appended claims. | Methods and systems for securing code in a reprogrammable security system are provided and may comprise detecting when a prior version of code is copied over a subsequent version of code. Operations within the system may be controlled based upon detection of the prior version of code. A unique version identifier may be associated with each successive version of code. The system may compare instances of unique version identifier from varied storage mechanisms on a device which may include flash memory, latch memory and one time programmable memory. The same instances of unique version identifier may be compared with a unique version identifier instance independently received from an external entity. When a comparison reveals a prior version of code copied over a subsequent version of code the system may conduct operations specified for a security breach. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the right of priority based on Taiwanese Patent Application No. 102142018 entitled “Hematocrit Measurement System and Measurement Method Using the Same,” filed on Nov. 19, 2013, which is incorporated herein by reference and assigned to the same assignee herein.
FIELD OF THE INVENTION
The present invention relates to a hematocrit measurement system and a measurement method thereof, and more particularly to a hematocrit measurement system having a capacitive reactance adjustor and a method of improving capacitive reactance characteristics of the blood hematocrit using the capacitive reactance adjustor so as to enhance measurement accuracy.
BACKGROUND OF THE INVENTION
In view of improper eating habits in the modern rich life, diet-caused diseases are increasing. Bioelectrochemical measurement systems with high reliable accuracy for those who require long-term monitoring health status (such as glucose, lipids, etc.) have gradually become an indispensable tool for life.
Conventional electrochemical and biochemical measurement systems may present significant errors for measurement results. That is because blood composition includes interference components to the measurement results. The most representative interference components that interfere are the proportion of red blood cells in the blood (i.e., hematocrit, hereinafter referred to as HCT). The blood HCT is an important parameter leading to occurrence of errors in measurement results. For example, in operating measurements of blood glucose, cholesterol, uric acid and blood clotting speed, red blood cells may impede reaction between the blood and an enzyme, causing the measurement result of high HCT presented lower than its actual value, while the measurement result of low HCT presented higher than its actual value.
With reference to current background art, there are a variety of technical solutions to solve the problems caused by HCT. For example, U.S. Pat. No. 5,628,890, the entity of which is incorporated herein by reference, discloses a test strip for an electrochemical system. A filter layer is disposed on the test strip to separate the red blood cells from the blood sample to be tested. However, the method disclosed in this patent has drawbacks such as difficulty to process the test strip, high cost, long measurement time taken, and large amount of measurement blood needed.
U.S. Pat. No. 7,407,811 discloses a method for detecting HCT and correcting the concentration of the blood to be tested. AC signals with frequencies in a range of 1 Hz-20 KHz are provided to test the blood sample. The phase angle and admittance magnitude of the blood can be measured and HCT values in the blood can be calculated therefrom. However, the technical solutions disclosed in this patent need repeated providing of two to five signals with different frequencies to the tested blood. It is a practical disadvantage that the blood HCT is measured by signals with different frequencies, resulting in long overall reaction time, operational difficulties, and increased power consumption.
In addition, U.S. Pat. No. 8,480,869 discloses an HCT measurement method using a redox reaction in which ferricyanide or ferrocyanide is disposed on electrochemical test strip electrodes. After ferricyanide or ferrocyanide reacts with red blood cells, the HCT value can thereby be measured. However, the redox agents disclosed in U.S. Pat. No. 8,480,869 may interfere with other enzymes on the electrochemical test strip, resulting in a distortion of the measurement results. Further, although both U.S. Pat. Nos. 7,407,811 and 8,480,869 disclose methods to measure HCT values of the blood, other components in the blood can also pose a threat to the accuracy of HCT measurement. Moreover, although U.S. Pat. No. 5,628,890 discloses that the red blood cells can be separated from the blood for testing, the presence of HCT cannot be completely filtered out. Accordingly, HCT measurement systems with high accuracy and reliability are needed for the industry based on overcoming the above disadvantages of conventional technologies.
SUMMARY OF THE INVENTION
One aspect of the present invention provides an HCT measurement system, comprising an electrochemical test strip and a measuring instrument, wherein blood HCT capacitance characteristics and measurement accuracy can thus be effectively improved using a blood measuring instrument with a capacitive reactance characteristic adjustor.
The a measurement apparatus comprises: a power generator providing a signal; a connector transmitting an initial signal generated from a blood sample to the measurement apparatus; a capacitive reactance adjustor disposed between the test strip and the measurement apparatus; a calculation unit for calculating concentration and HCT value of the blood sample; an A/D convertor transforming the corresponding initial signal to a digital reacted signal; and a signal processor processing the digital signal and showing measured results on a display, wherein the calculation unit measures the signal to calculate the HCT value of the blood sample such that distortion measurement signal curves due to saturated or cut off signal waveform voltage is prevented.
According to an embodiment of the invention, the adjusting capacitor of the signal processor and a capacitance of the blood sample present a parallel relationship, wherein an overall circuitry capacitance C eq of the signal processor satisfies the following equation:
C eq =C b +C ac ,
where C eq is the overall circuitry capacitance, C b is the capacitance of the blood sample, and C ac is the adjusting capacitance, thereby amplifying the measurement signal and achieving effects of reducing the required amount of blood.
According to another embodiment of the invention, the adjusting capacitor of the signal processor and a capacitance of the blood sample present a serial relationship, wherein an overall circuitry capacitance C eq of the signal processor satisfies the following equation:
1 /C eq =1 /C b +1 /C ac ,
where C eq is the overall circuitry capacitance, C b is the capacitance of the blood sample, and C ac is the adjusting capacitance, thereby effectively filtering interference signals.
Further, the calculation unit measures a voltage division signal to calculate the HCT value of the blood sample such that distortion measurement signal curves due to saturated or cut off signal waveform voltage can be prevented.
According to another embodiment of the invention, a method for measuring hematocrit (HCT) using an HCT measurement system comprises: providing an electrochemical test strip; placing the electrochemical test strip into the HCT measurement system (e.g., as set forth herein); providing a wave function signal to the electrochemical test strip transmitted from a power generator to the connector and the capacitive reactance adjustor; acquiring a measuring signal through the calculation unit; analyzing the measuring signal through the signal processor; and showing a measured HCT value on a display through the signal processor or using the HCT value to calculate concentration of other compositions of sample.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated by reference to the following detailed description, when taken in conjunction with the accompanying pictures, wherein:
FIG. 1 illustrates an exploded view schematically showing the structure of the electrochemical test strip according to an embodiment of the invention;
FIGS. 2 a -2 d schematically show layouts of electrode systems according to embodiments of the present invention;
FIG. 3 is a block diagram schematically illustrating a system of the measurement apparatus according to an embodiment of the present invention;
FIG. 4 is an equivalent circuitry of a calculation unit 312 a according to an embodiment of the present invention;
FIG. 5 is an equivalent circuitry of another computing unit 312 b according to another embodiment of the present invention;
FIGS. 6 a -6 p show equivalent circuit diagrams of capacitance characteristic adjustment device according to embodiments of the present invention;
FIG. 7 schematically illustrates comparison results between the measured adjusted capacitor in parallel arrangement and the measurement apparatus without characteristic capacitance adjustor;
FIG. 8 shows the comparing results of the coefficient of variation (CV) of the output signals by each measurement apparatus; and
FIG. 9 is a flow chart illustrating a method for HCT measurement using the HCT measurement system of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Reference will now be made in detail to several exemplary embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts. In the drawings, the shape and thickness of an embodiment may be exaggerated for clarity and convenience. Note that the features illustrated in the drawings are not necessarily drawn to scale. Descriptions of well-known components, materials, and process techniques may be omitted so as to not unnecessarily obscure the embodiments of the invention. Any devices, components, materials, and steps described in the embodiments are only for illustration and not intended to limit the scope of the present invention.
Embodiments of the present invention provide a method for measuring blood HCT using a biochemical system. The biochemical system comprises a measurement apparatus and an electrochemical test strip, wherein the electrochemical test strip includes at least one pair of electrodes. When operating the measurement apparatus, the users insert the electrochemical test strip into the measurement apparatus. A patient's skin is then pricked using a blood collection needle to ooze trace blood, which is directly dripped onto the electrochemical test strip. When the blood is dripped and sucked into the reaction layer on the top of the electrode, HCT concentration can be measured by measuring the resistance and capacitance of the blood. That is because the red blood cells in the blood include capacitive and resistance characteristics in structure such that there is a direct relationship between use of the capacitive and reactance characteristics and the HCT concentration.
FIG. 1 illustrates an exploded view schematically showing the structure of the electrochemical test strip according to an embodiment of the invention. Referring to FIG. 1 , an electrochemical test strip 100 includes an insulating substrate 102 , an electrode system 104 , an insulating layer 106 , a lower separation plate 108 , a hydrophilic separation plate 110 and an upper separation plate 112 . The insulating substrate 102 is an electrically insulating substrate, and its material may include, but is not limited to: polyvinyl chloride (PVC), glass fiber, polyester, bakelite, polyethylene terephthalate (PET), poly carbonate esters (PC), polypropylene (PP), polyethylene (PE), polystyrene (PS), ceramic or any combination thereof.
Materials of the electrode system 104 may include any conductive material, such as carbon plastic, silver plastic, copper, rubber, gold and silver mixed glue, carbon silver mixed glue, or any combination thereof. In one embodiment, the electrode system is composed of a carbon powder conductive layer. In another embodiment, the electrode system is composed of a metal layer. In further another embodiment, the electrode system is composed of a silver-based conductive layer and a carbon powder conductive layer located thereon, wherein impedance of the carbon powder conductive layer is typically much greater than that of the silver-based conductive layer or other metal layer. Further, according to embodiments of the invention, in response to the actual needs in measurement, the electrode system can be a set of electrodes consisting of a plurality of electrodes insulated from each other. In the present embodiment, the electrode system comprises a concentration electrode set and an HCT electrode set. The concentration electrode set comprises a working electrode and a reference electrode insulating from each other. The HCT electrode set comprises a first HCT electrode and a second HCT electrode. In measurement, the working electrode, the reference electrode, the first HCT electrode and the second electrode are electrically connected to a measurement apparatus and a blood sample respectively. Note that the present invention does not intend to limit the configuration of the electrodes, as long as an electrical circuit can be formed between the electrode set and the measurement apparatus. Generally, it would be sufficient to exploit the present invention as long as each electrode of the aforementioned electrode configuration is insulated from each other before connecting the blood sample. Embodiments of the present invention are not intended to be limited by the arrangement between the electrodes and are not intended to be limited by the number of electrodes; other electrodes may be added depending on the practical application.
The insulating layer 106 covers part of the electrode system 104 so that a reaction zone for receiving a blood sample is formed at one end of the electrode system 104 not covered while the other end forms a connection area in contact with the measurement apparatus, wherein the reaction zone includes an inlet for injecting the blood sample. Materials of the insulating layer 106 can include, but are not limited to a PVC insulating tape, a PET insulating tape, a thermal drying insulating paint or an ultraviolet drying insulating paint. According to one embodiment of the invention, the electrochemical test strip 100 may include at least one reaction layer disposed in the reaction zone. The reaction layer contains at least one oxidoreductase to produce a chemical reaction with the blood sample, wherein the type of oxidoreductase is determined depending on the nature of the blood sample. Further, the reaction layer covers at least part of the reaction zone of the electrode system.
The lower separation plate 108 is disposed over the insulating layer 106 , and the lower separation plate 108 includes an opening 109 exposing a portion of the electrode system. Generally, it would be sufficient to implement as long as the opening 109 exposed part of the electrode system. The present invention does not intend to limit the shape of the opening 109 . Further, the connecting region of the insulating substrate 102 is exposed by the lower separation plate 108 such that one end of the connection area of the electrode system electrically connects the measurement apparatus. Materials of the lower separation plate 108 can include, but are not limited to a PVC insulating tape, a PET insulation tape, a thermal drying insulating paint or an UV curable insulating paint. Furthermore, during the manufacturing process of the lower separation plate 108 , the lower separation plate with the trimmed opening can be placed on the insulating substrate and the electrode system. Alternatively, the lower spacer can be formed on part of the insulating substrate and the electrode system by directly printing and selectively avoiding the opening 109 and the position of the connection region of the insulating substrate.
Materials of the upper separation plate 112 can include, but are not limited to transparent or translucent material so as to easily observe whether the reaction zone is filled with the blood sample and to avoid testing with the blood sample unfilled, resulting in erroneous measurements. The lower surface of the upper separation plate 112 near the reaction zone can be coated with a hydrophilic spacer 110 to enhance capillary action on the internal walls of the reaction zone and more rapidly and efficiently introduce the blood sample into the reaction zone. The upper separation plate 112 further comprises a vent hole corresponding to the openings (not shown) to enhance capillary action, exhausting gas in the reaction zone. In general, the vent hole is disposed near the end of the inner closed opening. Embodiments of the present invention are not limited to the shape of the vent hole, for example, circular, oval, rectangular, diamond, etc.
In one embodiment, the electrochemical test strip 100 can be provided with an identification unit 114 , which is formed on the side of upper surface of the electrode system 104 which is in contact with the measurement apparatus. The identification unit 114 includes a plurality of electrical components. The electrical components can be a variety of electrically conductive elements such as electrical elements having electrical characteristics of passive components. In one embodiment, the electrical element can be a resistor which is the same as the material of the electrode system 104 . The electrical element can be formed by screen printing, imprinting, thermal transfer printing, spin coating, ink-jet printing, laser ablation, deposition, electroplating, or screen-printing. In another embodiment, the electrical device comprised in the identification unit 114 may include resistors, capacitors, inductors, and/or combinations thereof. When the identification unit 114 is inserted in a measurement device, the measurement device can identify the location and quantity of each electrical component on the electrochemical test strip 100 meter, thereby identifying the kind of the electrochemical test strip 100 and further adopting corresponding correction parameters or measurement modes. In other words, the number and location of a plurality of electrical components determine an identification code of the electrochemical test strip 100 so that the measurement apparatus can accordingly identify electrochemical test strip 100 . The present invention does not intend to limit the number, shape or configuration of the electrical elements comprised in the identification unit 114 . The present invention does not intend to limit the location or operating mode of identification unit 114 . The only implement criteria for the identification unit 114 is that the identification code can be read by the measurement apparatus. Additional identification units alternatively implemented are disclosed in other Taiwanese patent applications filed by the same applicant including Taiwanese Application Nos. 096146711, 097202289, 097208206, 097207619, 097133258, 098202095, 098131024, 098215494 and 099144438, the entirety of the abovementioned applications are incorporated herein by reference.
FIGS. 2 a -2 d schematically show layouts of the electrode system according to some embodiments of the present invention. Referring to FIGS. 2 a -2 d respectively, fulfilling the measurement requirements, an electrode system including a plurality of sets of electrodes is disposed on a single electrochemical test strip. According to embodiments of the present invention, the electrode system includes but is not limited to a concentration electrode set and an HCT electrode set. The concentration-electrode set includes at least one working electrode W and a reference electrode C. HCT measurement does not contain redox reaction. Since a signal waveform is provided by the measurement apparatus in the blood, the HCT response signal can be measured therefrom. The HCT electrode set for measuring HCT is composed of a first HCT electrode H1 and a second HCT electrode H2.
According to embodiments of the present invention, arrangement of each electrode set is not particularly limited. When the blood sample infuses into entrance I of the reaction zone, it comes into contact with the HCT electrode set and the concentration electrode set of the electrode system sequentially. Note that the entrance sequence of the blood samples contacting electrodes of the reaction zone is not limited, and the electrode sets can be adjusted according to actual required measurement position, if only one electric loop can be formed between the electrode set and the blood sample, thus sufficiently implementing measurement embodiments of the invention. In one embodiment, configuration of the electrode set of the electrochemical test strip is shown in FIG. 2 a . Working electrode W and reference electrode C of the concentration electrode set are set up closer to the entrance I of the blood sample than the HCT electrode set. In another embodiment, an alternative configuration of the electrode set of the electrochemical test strip is shown in FIG. 2 b . The first HCT electrode H1 and the second HCT electrode H2 of the HCT electrode set are set up closer to the entrance I of the blood sample than the concentration electrode set. In a further embodiment, an alternative configuration of the electrode set of the electrochemical test strip is shown in FIG. 2 c . Working electrode W and reference electrode C of the concentration electrode set are set up between the first HCT electrode H1 and the second HCT electrode H2 of the HCT electrode set. Further, configuration of the electrode set of the electrochemical test strip of the present invention can also be shown in FIG. 2 d . In addition to the concentration electrode set and the HCT electrode set, there are other electrode sets O included. Note that the present invention does not intent to limit layouts and measuring the relationship between each of the electrode sets. The electrical connection relationship can be adjusted according to actual measurement needs. A single measurement implementation can be individually performed between the electrode sets. More than one measurement implementation can also be performed on the same electrode set. For example, HCT and concentration measurements can be implemented on the same electrode set. Another embodiment of the electrode system may include a shape electrode, which is electrically insulated from each measurement electrode. The shape electrode is configured to electrically connect with the measurement apparatus. When the electrochemical test strip is inserted into the measurement apparatus, an electrical loop is formed between the shape electrode and the measurement apparatus, thereby starting the measurement operation.
For simplification of the specification, the following description is only focused on the HCT measurement. Those skilled in the art, however, can easily combine the HCT measurements disclosed in the invention with other measurements of physiological parameters. For example, the HCT value of the blood sample can be acquired through the HCT measurement method of the present invention, thereby using the HCT value to calculate the biochemical concentration values, which are not limited to glucose, cholesterol, uric acid, lactic acid, and hemoglobin.
When the blood sample flows into the electrochemical test strip, a waveform signal is applied to the reactive layer by the measurement apparatus. After the waveform signal is reacted with the blood sample, an electrical signal will be released, generating a corresponding response signal. By measuring the response signal, the HCT condition of the user can be revealed at the measurement moment.
In the present disclosure, the waveform signal is defined as signals that are stabilized over time and are undulated with circulated current or voltage. The signals can be 100% of AC signals, or the AC and DC superimposed signals, preferably DC signal waveforms. The aforementioned DC waveform signal means when the measurement apparatus provides a signal to the reaction zone of the electrochemical strip, a single signal waveform sufficiently presents characteristics of the waveform, and the waveform characteristic signal does not contain a negative circulated signal. The DC waveform signal can be, but is not limited to a pulse wave, a square wave, a triangle wave or a saw-tooth wave. In the present embodiment, the preferable waveform signal is a square wave signal with frequency approximately in a range of 1 KHz-22 KHz. Voltage is in a range of 50 mV-5 V, preferably in a range of 300 mV-800 mV.
FIG. 3 is a block diagram schematically illustrating a system of the measurement apparatus according to an embodiment of the present invention. The system of the present invention includes an electrochemical test strip 320 and a measurement apparatus 310 . The electrochemical test strip 320 comprises a concentration electrode set with a reference electrode C and a working electrode W for concentration measurement, and an HCT electrode set with a first HCT electrode H1 and a second HCT electrode H2 for HCT measurement. The measurement apparatus 310 includes a connector 311 for external connection, a calculator 312 for transforming a concentration and/or HCT value, an analog to digital converter 313 , a processor 314 and a display 315 . After the blood sample flows into the reaction zone of the electrochemical test strip, the blood sample distributes over the concentration electrode set and the HCT electrode set. When a waveform signal is applied by the power unit 316 to the HCT electrode set, the red blood cells in the blood reacts with an electrical signal to generate a corresponding response signal which is transmitted through the connector 311 to the calculation unit 310 of the measurement apparatus 312 . Subsequently, the reaction signal is transformed and transmitted to the analog to digital converter (ADC), to get a digital response signal. The digital response signal is further processed by a processor 314 , and/or the measurement results are presented on a display 315 .
FIG. 4 is an equivalent circuitry of a calculation unit 312 a according to an embodiment of the present invention. Unlike traditional circuit direct using signal gaining measurement, the calculation unit 312 a of the present embodiment adopts voltage division principles to get the blood HCT value. Technical effects such as prevention of measured signal curve distortion caused by signal cut off and/or saturation generated by signal voltage waveform can thus be achieved. The calculation unit 312 a is comprised with a divider resistor 410 and signal processor 412 . When a waveform signal is provided by the power supply unit 316 through the connector to the blood sample 322 , the waveform signal will pass through the divider resistor 410 , and the divider resistor 410 and the blood sample 322 are in series relationship. In a series circuit, current through each impedance element is equivalent in accordance with Ohm's law. Since the current through the divided resistor and current through the electrochemical strip with blood sample are the same, measuring the current through the divided resistor can get the current flowing through the blood sample. Further, according to Kirchhoff's voltage law and Ohm's law, the voltage on both ends of each impedance element is equal to the sum of voltage on all components of the circuit. The voltage Vo at signal output terminal satisfies the following relationships:
Vo= [ R SR /( R SR +R BR )] Vs (1)
where R SR is impedance of the blood sample, R BR is the divided resistor, and Vs is voltage at the power supply terminal.
According to embodiments of the invention, although there is no restriction on impedance of the divided resistor, it is preferable to not affect measurement of the blood signal by the calculation unit. The impedance is preferably in a range of 200Ω-2 MΩ), more preferably in a range of 2 KΩ-700 KΩ, and further more preferably in a range of 20 KΩ-200 KΩ. Further, the measurement signal is then processed by a signal processor 412 . The signal processor 412 can comprise but is not limited to an operational amplifier, an adder, a single integrator or a circuit composed thereof. More preferably, the signal processor is a subtractor.
A lipid bilayer of the red blood cell constitutes an insulating layer. The insulating layer can divide the inner fluid and the outer fluid of the cells, thereby forming a capacitor-like structure. The red blood cells thus have physical characteristics similar to a capacitor. For the household application, the amount of blood samples needed for the measurement system is approximately 15 μL-0.1 μL, or even lower. However, empirical experiment shows that 0.5 μL blood sample contains capacitance of 150 pF-1.5 nF. For conventional electrochemical systems, other components in blood can significantly interfere with the measuring signals, resulting in variation of the measurement results.
In addition, the red blood cell membrane comprises Na+/K+-ATPase. When applying an external electric signal to the blood sample, sodium or potassium ions with electrical signals can be released from the Na+/K+-ATPase due to the potential difference between inside and outside the cell, so as to achieve a potential balance inside and outside the cell. While measuring the HCT value, a signal waveform is provided by the measurement apparatus. Potential in the blood changes as alternately applying the positive and zero potential. Repetitive potential difference between inside and outside the cell causes continuous import and export of sodium or potassium ions from the Na+/K+-ATPase to achieve a potential balance inside and outside the cell. However, the potential difference of the signal is the main course of the noise interference during HCT measurement, further affecting measurement accuracy.
FIG. 5 is an equivalent circuitry of another computing unit 312 b according to another embodiment of the present invention. In order to accurately and precisely detect capacitance characteristics in the blood and improve accuracy of the HCT measurement, a blood capacitance characteristic adjustment device 420 is particularly added in the junction of the electrochemical test strip and the measurement apparatus according to an embodiment of the invention. The capacitance characteristic adjustment device 420 is used to present an electrical connection relationship, thereby improving the capacitance accuracy measured by the measurement apparatus. In addition, since the capacitance characteristic adjustment device 420 can amplify the HCT blood concentration value, the amount of blood sample required for the measurement is apparently reduced.
FIGS. 6 a -6 p show equivalent circuit diagrams of capacitance characteristic adjustment device according to embodiments of the present invention. The capacitance characteristic adjustment device may include, but is not limited to a load resistor and an adjustment capacitance. A junction “a” is created at the electrical connection between a voltage divider resistor and a signal processor. The adjusted capacitance component is composed of a single capacitor or a plurality of capacitive elements. In one embodiment, since a constant of impedance exists in the electrochemical test strip, the loading resistors of FIGS. 6 a , 6 g and 6 l can be substituted by the impedance of the electrochemical test strip.
Further, variation of electrode impedance values for each production batch may exist due to inevitable differences among each batch of material during the manufacturing process of the electrochemical test strip. The loading resistance of the capacitance characteristic adjustment device and the blood sample of the present invention are presented in an electrical connection relationship. The impedance of the electrode can thus directly affect the electrical signals detected by the measurement apparatus. The impedance difference of each batch electrode may result in the difference variation of the electrochemical test strip batch by batch. An identification unit of the electrochemical test strip can thus be used to record the corrected impedance difference of the electrode of each batch. When the electrochemical test strip is inserted into the measurement apparatus, the measurement apparatus reads the corrected impedance difference of the electrode of each batch through the identification unit. The measurement results are corrected by the correction value to avoid measurement errors created by batch-to-batch variation of the electrode impedance difference.
In light of capacitive characteristics of red blood cells in the blood sample, FIGS. 6 a -6 f show a relation between adjustment capacitance of the capacitance characteristics adjustment capacitor and capacitance of the blood sample which is in a parallel relationship such that the overall circuit capacitance C eq satisfies the following simplified equation:
C eq =C b +C ac (2)
where C eq is the overall capacitance of the circuit, C b is capacitance of the blood sample, an C ac is the adjustment capacitance.
The object of arranging the blood sample in parallel with the adjusted capacitor is to increase stored energy of the capacitance characteristics in the overall circuit, to increase the capacitance value of the overall circuit, and to improve sensitivity to the HCT characteristic signal. Further, arranging the adjustment capacitor in parallel can stabilize voltage and filter the Na+/K+-ATPase and measurement noises caused by other components in the blood. Measurement accuracy can also be improved such that calculation circuit can precisely calculate the capacitance characteristics of blood. In addition, reaction signal can be amplified by arranging the adjustment capacitance in parallel, thereby reducing the amount of blood samples needed to achieve the purpose of minimized detection.
FIG. 7 schematically shows comparison results between the measured adjusted capacitor in parallel arrangement and the measurement apparatus without characteristic capacitance adjustor, illustrating the output signal-time relationship with respect to 10%, 30% and 50% of HCT concentration respectively. Referring to FIG. 7 , as comparative examples, after inputting the measurement signal, a reaction begins occurring in the blood sample. Signals gradually rise to a steady state within at least 0.8 seconds. In contrast, the adjustment capacitor is in parallel with the blood sample of the present invention. When an electrochemical test strip is inserted into the measurement apparatus and starts a measuring process, energy storage has been proceeding with the adjustment capacitor. When the blood sample flows into the reaction zone of the electrochemical test strip, the adjustment capacitor starts to release energy until the blood sample begins to release the response signal which is superimposed on the energy released by the capacitor. The rise time of the response signal by the blood sample can thus be reduced within 0.4 seconds to a steady state, thereby with the effect of reducing the measurement time.
In FIGS. 6 g -6 k , the relationship between the adjusted capacitance of the capacitance characteristic adjustor and the capacitance of the blood sample is presented in series, such that the capacitance C eq of the overall circuit satisfies the following simplified equation:
1 /C eq =1 /C b +1 /C ac (3)
The capacitors in series are equivalent to expanding the distance of capacitor electrode, thus reducing the overall capacitance. Surprisingly, though the overall capacitance of the circuit is reduced, electrical signal detected by the measurement apparatus is also reduced. Detected noises caused by the Na+/K+-ATPase and other components in the blood may also be reduced such that the HCT concentration may be easily analyzed by a calculation unit, thereby effectively reducing influence by other components in the blood.
In FIGS. 6 l -6 p , the relationship between the adjusted capacitance and the blood sample is presented in series and in parallel, such that the capacitance C eq of the overall circuit satisfies the following simplified equation:
C eq =[( C C1 *C b )/( C C1 +C b )]+ C C2 (4)
When the capacitor is both in series and in parallel with the blood sample, the blood sample is in series with C C1 so as to reduce noise caused by the Na+/K+-ATPase and other components in the blood. The capacitance value of overall circuit is then increase by C C2 , to facilitate capture of the signal by the calculation unit.
According to embodiments of the present invention, there is no limitation to the adjusted capacitance value of capacitance characteristics adjustor. The capacitance value, however, is limited to not affecting the capacitance properties of the blood sample. The capacitance value is preferable in a range of 1 pF-150 μF, more preferable in a range of 50 pF-20 μF.
In the following comparative examples, commercially available biological complex impedance measurement circuit is used with a carbon electrode and a metal electrode in measured HCT comparison with the electrochemical test strip of the present invention. The implementation steps are disclosed as follows:
1. Two biological complex impedance measurement circuits are respectively connected to a carbon electrode electrochemical test strip and a metal electrode electrochemical test strip. Then the measuring circuit of the present invention is connected to a carbon electrode electrochemical test strip of the same model and production batch. 2. The blood samples with various HCT concentrations were respectively placed and dripped onto the carbon electrode electrochemical test strip and the metal electrode electrochemical test strip. 3. Measurement signals of each circuit are retrieved within 30 seconds. 4. The above steps are repeated for five times.
By implementation of the abovementioned steps, the response signal curve of the HCT with each measurement apparatuses can be acquired. The response curve can be converted to a current signal by means of a backend operation circuit. The HCT measurement signal containing interfering signals may present in the results in each measurement apparatus due to reaction(s) caused by other components in the blood.
FIG. 8 shows the comparing results of the coefficient of variation (CV) of the output signals by each measurement apparatus. Those skilled in the art generally appreciate that the coefficient of variation represents error to the measurement results. Referring to FIG. 8 , a mean error of comparative example 1, in which a biological complex impedance measurement circuit is connected with a carbon electrode electrochemical test strip, is 2.6%. In comparative example 2, the biological complex impedance measurement circuit is in conjunction with a metal electrode electrochemical test strip. Due to excellent conductivity of the metal electrode, influence on impedance of the electrode can be prevented. The coefficient of variation of the metal electrode is smaller than that of the carbon electrode. For example, the coefficient of variation of the metal electrode is 0.6%. According to embodiment 1, interference to HCT measurements caused by other components in the blood can be effectively reduced due to provision of the capacitance characteristic adjustor. According to embodiments of the present invention, the average measuring error is only 0.12% in conjunction with a carbon electrode electrochemical test strip, and can be maintained at 0.1% level for 10% to 60% concentration of measurement, or the error can be even closer to 0.
FIG. 9 is a flow chart illustrating a method for HCT measurement using the HCT measurement system of the present invention. First, an electrochemical test strip for measurement is provided (step S 810 ). The electrochemical test strip may include, but is not limited to four electrodes insulated from each other: a working electrode, a reference electrode, a first electrode HCT measurement electrode and a second HCT measurement electrode, wherein the first and second HCT measurement electrodes are electrically connected to the measurement apparatus and the capacitance characteristic adjustor. As mentioned above, the adjusted capacitance of the capacitor characteristic adjustor and the blood sample are in series and/or in parallel relationship. Next, the electrochemical test strip is inserted into a measurement apparatus (step S 820 ). The measurement apparatus can be started by the insert action or be started manually. After starting the measurement apparatus, a waveform signal is provided by the power supply unit through the connector and the capacitance characteristics adjustor to the electrochemical test strip (step S 830 ). Subsequently, a measurement signal is acquired by a computing unit (step S 840 ). For example, the signal of divided voltage can be measured by the measurement apparatus, and the signal processor of computing unit retrieves the signal on impedance of the voltage divider. Thereafter, the measurement signal is analyzed by the signal processor (step S 850 ). The signal is digitized by an analog-digital converter and transmitted to the processor. The measurement results by the processor are shown on a display or the HCT value can be used for calculation of other biochemical concentration measurement (step S 860 ). The digitized signal of the measurement results received by the processor can be directly displayed on a monitor, or other biochemical concentration can be calculated by means of the HCT value.
While the invention has been described by way of examples and in terms of preferred embodiments, it would be apparent to those skilled in the art to make various equivalent replacements, amendments and modifications in view of specification of the invention. Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such replacements, amendments and modifications without departing from the spirit and scope of the invention. | A hematocrit (HCT) measurement system and measurement method using the same are disclosed. The hematocrit (HCT) measurement system comprises a test strip and a measurement apparatus comprising: a connector transmitting an initial signal generated from a blood sample to the measurement apparatus, a capacitive reactance adjustor disposed between the test strip and the measurement apparatus, a calculation unit for calculating concentration and HCT value of the blood sample, an A/D convertor transforming the corresponding initial signal to a digital signal, and a signal processor processing the digital reacted signal and showing measured results on a display, wherein the HCT value is calculated by voltage partition to prevent the signal waveform voltage being saturated or cutoff, thereby resulting in measured signal distortion. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation application of U.S. application Ser. No. 12/977,627 filed on Dec. 23, 2010, the contents of which are hereby incorporated by reference, which claims priority from Japanese patent application serial no. 2010-002605 filed on Jan. 8, 2010, the contents of which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to dies for applying insulation enamel coatings to wires (hereinafter referred to as “coating dies”), and particularly to dies for coating flat wires (which are advantageously used to increase the filing factor (space factor) of coils). Furthermore, the invention relates to enameled flat wires and methods for manufacturing enameled flat wires using the invented dies.
[0004] 2. Description of Related Art
[0005] Enameled wires (enamel covered insulated wires) are widely used for coil wires in electrical equipment such as motors and transformers. Such enameled wires are formed by covering an insulation coating around a metal conductor having a desired cross section (such as circular or rectangular) depending on the shape and application of the coil. With the current trend toward small and high power vehicle motors (such as alternators), increasing demands exist for enameled flat wires (having a rectangular cross section) that can be wound into a coil more densely than enameled round wires (having a circular cross section). In order to achieve more accurate coil winding and a higher coil filling factor, there also exist demands for thinner and more uniform insulation enamel coatings.
[0006] Known coating dies for applying an insulation enamel (varnish) around a conductor are classified into die assemblies and solid dies. Die assemblies will be explained first. FIG. 1 is a schematic illustration showing, an example of a die part of a die assembly for flat wire coating, front, side and top views and an enlarged view of the principal portion. FIG. 2 is a schematic illustration showing a top view of a die assembly assembled from four die parts shown in FIG. 1 .
[0007] As illustrated in FIG. 1 , the die part 1 includes a cylindrical die body 2 and an approximately cubic die base 3 . The die base 3 has an insertion hole 4 for insertion of the die body 2 of another die part 1 . The cylindrical surface of the die body 2 has numerous annular coating grooves 5 for supplying an insulation varnish therethrough in order to apply the varnish around a flat wire conductor. As illustrated in FIG. 2 , a die assembly 6 for flat wire coating is assembled from four FIG. 1 die parts 1 . The space surrounded by the four die parts 1 forms a die hole 7 for insertion of a flat wire conductor in order to apply an insulation varnish around the conductor.
[0008] Such die assemblies for enameling flat wires (also referred to as “flat wire coating die assemblies”) as shown in FIGS. 1 and 2 have an advantage of being adaptable to different size flat wire conductors. That is, the die hole size of a die assembly can be changed by adjusting the insertion depth of each die body into the corresponding die base hole when assembling the die assembly from a set of die parts (four parts in FIG. 2 ). Also, die assemblies have another advantage that a die assembly can be readily assembled and disassembled, and therefore it can be replaced with another die assembly without the need for cutting a flat wire conductor.
[0009] Although die assemblies have the above advantage of being adaptable to different size flat wire conductors, they have the following disadvantage. It is difficult to accurately and controllably adjust the gap between the die hole of a die assembly and a flat wire conductor to be coated. Therefore, die assemblies cannot be used to form enameled wires requiring a very small allowable error (or tolerance) for the coating thickness or the finished dimensions.
[0010] Next, solid dies will be explained. Solid dies include: A die body (typically, approximately cylindrical) and a die hole of a fixed shape and dimensions formed through the die body. As just noted, the die hole of solid dies has a fixed shape and dimensions. Therefore, the gap between a die hole and a conductor to be coated can be accurately adjusted, and as a result an insulation varnish can be uniformly applied around the conductor. Thus, solid dies are suitably used to manufacture enameled wires requiring a small tolerance for the coating thickness or the finished dimensions.
[0011] Besides the above two types of coating dies, JP-A 2003-297164 discloses an assemblable/disassemblable coating die which combines the advantage of the accurate coating capability of solid dies with the advantage of the assemblability/disassemblability of die assemblies. Needless to say, the die hole of solid dies for enameled flat wires (also referred to as “flat wire coating solid dies”) has a rectangular cross section.
[0012] There still remains a yet-unsolved problem shared by all of the above listed types of coating dies—circumferential nonuniformity in coating thickness. More specifically, a coating formed around a flat wire by a conventional coating die is prone to be selectively thinner on each rounded corner of the flat wire and thicker on the both sides of the corner. That is, an undesirable local thickening/thinning phenomenon (what is called a dog-bone phenomenon, see later-described FIG. 7 ) is prone to occur on each rounded corner of the flat wire. Conventional thinking has been that this phenomenon is caused by the surface tension difference of an applied insulation varnish and is unavoidable in coatings formed by conventional coating dies.
[0013] There has been a strong demand for solutions to this problem because thickness nonuniformities of an insulation coating (such as a dog-bone surface) may degrade the high voltage electrical insulation and also may make accurate coil winding difficult. In order to prevent such a undesirable local thickening/thinning phenomenon, JP-A 2004-134113 discloses an insulated flat wire in which each corner of a flat wire conductor to be coated is shaped in such a manner that the cross section has a polygonal shape (i.e., has two or more vertices). The total number of vertices per flat wire conductor is 8 or more, and each vertex angle is 120° or more. According to this JP-A 2004-134113, the corners of the flat wire conductor are not exposed to the coating surface, the coating thicknesses on the corners of the conductor are sufficiently thick, and the resulting insulated flat wire has excellent electrical insulation properties.
[0014] As described above, there is an increasing demand for enameled flat wires in terms of the filling factor of coil windings as well as for uniform insulation enamel coatings in terms of breakdown voltage and coil winding accuracy. The technology disclosed in the above JP-A 2004-134113 has an advantage that an insulation coating can be uniformly formed. However, the cross section of the flat wire conductor used in this technology is close to a race-track shape (or an elongated circle) rather than a rectangle; therefore, coils wound from such a flat wire may not have a satisfactorily high filling factor.
[0015] As for solid dies, they can be advantageously used to form uniform insulated round wires. However, even solid dies cannot be effectively used to form uniform enameled flat wires because the above-described undesirable local thickening/thinning (dog-bone) phenomenon inevitably tends to occur. And, there have not yet been proposed any practical solutions to this problem of local thickening/thinning (dog-bone) phenomenon accompanying the flat wire enameling processes.
SUMMARY OF THE INVENTION
[0016] In view of the foregoing, it is an objective of the present invention to provide an enameled flat wire having a uniform thickness enamel coating formed on the entire surface of a long flat wire conductor without any undesirable significant local thickening/thinning.
[0017] (I) According to one aspect of the present invention, there is provided an enameled flat wire, comprising: a flat wire conductor having a rectangular cross section composed of four flat surfaces and four rounded corners; and an enamel coating formed on an entire surface of the flat wire conductor with a predetermined thickness for electrical insulation,
[0018] wherein a difference in a thickness of the enamel coating on the flat surfaces between a maximum thickness and a minimum thickness is equal to or less than 25% of the predetermined thickness.
[0019] As used herein and the appended claims, the term “rectangle (rectangular)” refers to a rectangle (including a square) whose four corners are rounded.
[0020] In the above aspect (I) of the present invention, the following modifications and changes can be made.
[0021] (i) A difference in a thickness of the enamel coating between on the flat surfaces and on the rounded corners is equal to or less than 20% of the predetermined thickness.
[0022] (ii) A difference in a thickness of the enamel coating between a maximum thickness and a minimum thickness is equal to or less than 25% of the predetermined thickness.
[0023] (iii) The predetermined thickness of the enamel coating is 20 μm or more, and 100 μm or less.
[0024] (iv) In the cross sectional view, a width and a length of the enameled flat wire are within a range from 0.5 to 17 mm.
ADVANTAGES OF THE INVENTION
[0025] According to the present invention, it is possible to provide a flat wire coating die, a manufacturing method of enameled flat wires, and an enameled flat wire, by which the entire surface of the entire surface of a long lat wire conductor is stably coated with a uniform thickness insulating coating without any undesirable significant local thickening/thinning. Also, by using enameled flat wires in accordance with at least some embodiments, accurate coil windings having a high filling factor can be provided.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] FIG. 1 is a schematic illustration showing, an example of a die part of a die assembly for flat wire coating, front, side, and top views, and an enlarged view of the principal portion.
[0027] FIG. 2 is a schematic illustration showing a top view of a die assembly assembled from four die parts shown in FIG. 1 .
[0028] FIG. 3 is a schematic illustration showing, an example of a conventional solid die for flat wire coating, a cross sectional view, and longitudinal sectional views along lines A and B.
[0029] FIG. 4 is an enlarged schematic illustration showing a cross sectional view of a coating portion of a conventional solid die for flat wire coating, where a flat wire conductor is passing through the coating portion.
[0030] FIG. 5 is a schematic illustration showing a cross sectional view of a case in which an insulation coating is formed around a flat wire conductor in a tilting relationship with each other when a conventional solid die is used for the flat wire coating.
[0031] FIG. 6 is a schematic illustration showing a cross sectional view of an example of an enameled flat wire formed by using a conventional solid die that suffers from an undesirable local thickening/thinning phenomenon.
[0032] FIG. 7 is a schematic illustration showing a cross sectional view of another example of an enameled flat wire formed by using a conventional solid die that suffers from an undesirable local thickening/thinning phenomenon.
[0033] FIG. 8 is a schematic illustration showing, an example of a solid die for flat wire coating according to the present invention, a cross sectional view, and longitudinal sectional views along lines A and B.
[0034] FIG. 9 is an enlarged schematic illustration showing a longitudinal sectional view of a die hole of an invented solid die for flat wire coating.
[0035] FIG. 10 is an enlarged schematic illustration showing a cross sectional view of a bearing portion (having a constant cross section) of a coating portion of a die hole of an invented solid die for flat wire coating, in which a flat wire conductor is passing through the bearing portion.
[0036] FIG. 11 is a schematic illustration showing a cross sectional view of an example of a flat wire covered with an insulation coating by using an invented solid die.
[0037] FIG. 12 is a schematic illustration showing a cross sectional view of another example of a flat wire covered with an insulation coating by using an invented solid die.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0038] The present inventor has extensively investigated the above-described undesirable local thickening/thinning phenomenon which occurs in flat wire enameling processes. In particular, the inventor has intensively investigated, for various cases, the insulation varnish flow just after the varnish application until the completion of the baking. The present invention was developed based on these results.
[0039] First, undesirable local thickening/thinning phenomena which occurs in insulation coatings formed by conventional solid dies for flat wire coating will be explained. FIG. 3 is a schematic illustration showing, an example of a conventional solid die for flat wire coating, a cross sectional view, and longitudinal sectional views along lines A and B. As illustrated in FIG. 3 , a conventional solid die 10 for flat wire coating includes a die body 8 and a die hole 9 for passing flat wire conductors therethrough. The die hole 9 includes: An entry portion having a cross section monotonically decreasing along the conductor insertion direction; a coating portion having a constant cross section; and an outlet portion having a monotonically increasing cross section.
[0040] FIG. 4 is an enlarged schematic illustration showing a cross sectional view of a coating portion of a conventional solid die for flat wire coating, where a flat wire conductor 20 is passing through the coating portion. As illustrated in FIG. 4 , the coating portion of the die hole 9 has a rectangular cross section having four straight sides 11 and four rounded corners 12 . And, the flat wire conductor 20 to be coated also has a rectangular cross section having four straight sides 21 and four rounded corners 22 .
[0041] The die hole 9 is slightly larger than the flat wire conductor 20 . And, the flat wire conductor 20 is coated with an insulation varnish by supplying the varnish into a gap between the die hole 9 and the flat wire conductor 20 . Thus, accurate positioning (centering) of the conductor 20 in the hole 9 (i.e., accurate alignment between the hole 9 and the conductor 20 ) is necessary to evenly apply the varnish around the conductor 20 .
[0042] In many cases, such an insulation varnish application and baking process as described above is repeated several times using different dies until a desired enamel coating thickness is obtained. Therefore, the above-described centering procedure also needs to be repeated for each varnish application process, thus incurring a problem of an increased overall centering procedure time (therefore, the problem of increased cost). Meanwhile, the degree of centering during each insulation varnish application and baking process is typically estimated by observation of a cross section of the resulting enameled wire.
[0043] FIG. 5 is a schematic illustration showing a cross sectional view of a case in which an insulation coating is formed around a flat wire conductor in a tilting relationship with each other when a conventional solid die is used for the flat wire coating. As illustrated in FIG. 5 , the flat wire conductor 20 is covered with the applied varnish 23 (the insulation coating 24 ) in a tilted and/or off-centered relationship both after the varnish application and after the baking. This phenomenon occurs relatively often in conventional processes of manufacturing flat wires.
[0044] A probable cause of such significant tilting and/or off-centering as shown in FIG. 5 is as follows: As already described, the cross section of the die hole 9 of the solid die 10 has the four straight sides 11 and the four rounded corners 12 . Therefore, an insulation varnish supplied does not evenly flow around the flat wire conductor 20 because the supplied varnish tends to flow into and accumulate on the corners 12 . As a result, once the conductor 20 is misalignedly inserted into the hole 9 or is caused to be misaligned by vibration or other factors after insertion, the conductor 20 cannot readily self-align relative to the hole 9 .
[0045] FIG. 6 is a schematic illustration showing a cross sectional view of an example of an enameled flat wire formed by using a conventional solid die that suffers from an undesirable local thickening/thinning phenomenon. As illustrated in FIG. 6 , the flat wire conductor 20 is evenly covered with the applied varnish 23 just after the varnish application. However, after the baking, the insulation coating 24 becomes thinner on the rounded corners 22 of the flat wire conductor 20 and becomes thicker than designed on the straight sides (flat surfaces) 21 .
[0046] As previously described, one commonly employed solution to this problem is that an insulation varnish is applied thicker on the rounded corners 22 than on the flat surfaces 21 . The effectiveness of such solutions was evaluated. FIG. 7 is a schematic illustration showing a cross sectional view of an example of an enameled flat wire formed by using a conventional solid die and the above-described non-uniform varnish application method which still suffers from an undesirable local thickening/thinning phenomenon.
[0047] As illustrated in FIG. 7 , the varnish applied on each rounded corner flows toward the neighboring flat surfaces as expected, but a thicker coating region is formed on both sides of the rounded corner, as a result exhibiting a more distinct dog-bone surface. Thus, the above-described non-uniform varnish application method still cannot offer a truly effective solution. Further, the dependency of the dog-bone surface formation on the thickness of the varnish 23 applied on the rounded corners 12 was examined. The results show that the smaller the minimum curvature radius of the rounded corners 12 of the die hole 9 is than the minimum curvature radius of the rounded corners 22 of a flat wire conductor 20 , the more pronounced the dog-bone phenomenon becomes.
[0048] A probable cause of such an undesirable local thickening/thinning phenomena as shown in FIGS. 6 and 7 is as follows: The surface curvatures (the inverses of the curvature radiuses) of an insulation varnish applied on each rounded corner of a flat wire conductor are different from (larger than) the surface curvatures on the adjacent flat surfaces. Thus, a surface curvature (surface tension) effect (a driving force of mass transfer caused by curvature difference) is exerted on the applied varnish during the coating process (just after the varnish application until the completion of the baking). And, such a surface curvature effect drives the varnish applied on each rounded corner of the conductor to flow toward the neighboring flat surfaces of the varnish. According to this assumption, it can be naturally inferred that the driving force of mass transfer in the FIG. 7 case (in which the minimum curvature radius of the rounded corners 12 of the die hole 9 is smaller than that of the rounded corners 22 of the flat wire conductor 20 ) is stronger than that in the FIG. 6 case (in which the minimum curvature radius of the corners 12 is approximately the same as that of the corners 22 ).
[0049] Preferred embodiments of the present invention will be described below. However, the invention is not limited to the specific embodiments described below, but various combinations and modifications are possible without departing from the spirit and scope of the invention.
[0050] (Outline Structure of Solid Die for Flat Wire Coating)
[0051] FIG. 8 is a schematic illustration showing, an example of a solid die for flat wire coating according to the present invention, a cross sectional view, and longitudinal sectional views along lines A and B. As illustrated in FIG. 8 , an invented solid die 30 for flat wire coating includes a die body 31 and a die hole 32 for passing flat wire conductors therethrough. The die hole 32 includes: An entry portion having a cross section monotonically decreasing along the conductor insertion direction; and a coating portion that at least includes a sub-portion having a constant cross section. The die hole 32 has a rectangular cross section, and has a plurality of inwardly projecting protrusions 33 on its inner surface. Meanwhile, as is often employed in wire drawing dies, the die body 31 may include, as a peripheral part of the die hole 32 , a nib and a nib holder for housing the nib.
[0052] Next, each part of the invented solid die for flat wire coating will be explained in detail.
[0053] (Die Hole)
[0054] FIG. 9 is an enlarged schematic illustration showing a longitudinal sectional view of a die hole of an invented solid die for flat wire coating. As illustrated in FIG. 9 , the entry portion has a monotonically decreasing cross section. The entry portion of FIG. 9 has front and back entry portions each having a different average taper angle. However, the entry portion may be configured with only the back entry portion. The back entry portion preferably has an average taper angle θ for example of 10° to 16°. The coating portion has at least a bearing portion having a constant cross section. The coating portion may include, on the conductor inlet side, a front streamlining (laminarizing) portion having a monotonically decreasing cross section and/or, on the conductor outlet side, a back streamlining (laminarizing) portion having a monotonically increasing cross section. Or, the coating portion may be configured with only the bearing portion.
[0055] Although, for simplicity of description, the taper angle of the inner surface of the FIG. 9 die hole abruptly changes at each boundary between adjacent die hole portions, the die hole inner surface is preferably formed to have a taper angle that gradually changes at each boundary. The protrusions 33 will be detailed later.
[0056] FIG. 10 is an enlarged schematic illustration showing a cross sectional view of a bearing portion (having a constant cross section) of a coating portion of a die hole of an invented solid die for flat wire coating, in which a flat wire conductor is passing through the bearing portion. As illustrated in FIG. 10 , similarly to the die hole 9 of the solid die 10 in FIG. 4 , a bearing portion of a die hole 32 of an invented solid die 30 for flat wire coating has a rectangular cross section having four straight sides (flat surfaces) 34 and four rounded corners 35 . However, the bearing portion of the solid die 30 has protrusions 33 on each flat surface 34 , unlike the solid die 10 in FIG. 4 .
[0057] The cross section of the bearing portion of the die hole 32 is not limited to any particular size, but is determined based upon the size of the flat wire conductor 20 to be coated and the desired coating thickness. Preferably, for example, the length W1 is from 1 to 17 mm, and the length W2 is from 0.5 to 4 mm.
[0058] (Protrusion)
[0059] As illustrated in FIGS. 9 and 10 , each protrusion 33 on the inner surface of the coating portion of an invented solid die 30 is an elongated ridge which preferably runs parallel to the conductor insertion direction. Furthermore, each protrusion 33 preferably extends along the entire length of the coating portion.
[0060] These protrusions 33 work as a streamlining plate for streamlining (laminarizing) the flow of an insulation varnish supplied, thus suppressing nonuniform (turbulent) varnish flow and as a result suppressing misalignment between the flat wire conductor 20 and the insulation coating around the conductor 20 . The protrusions 33 also mechanically suppress significant off-centering and/or tilting of the conductor 20 , thus reducing unevenness in coating thickness.
[0061] The top contour (perpendicular to the conductor insertion direction) of each protrusion 33 is preferably a circular arc, an elongated circular arc or an elliptical arc. In addition, the maximum curvature of the top contour of the protrusions 33 is preferably larger than that of the rounded corners 35 . Thus, the surface of the top portion of each protrusion 33 is free from sharp edges. Therefore, even when the flat wire conductor 20 contacts a protrusion (protrusions) 33 during the coating process, it will not be damaged. As used herein, the term “top portion of a protrusion” refers to a portion of the protrusion from about half of the height to the peak height, and the term “top contour of a protrusion” refers to the contour (perpendicular to a conductor insertion direction) of the top portion of the protrusion.
[0062] As just described, the maximum curvature of the top portion of the protrusions 33 is formed to be larger than that of the rounded corners 35 . This has the following effects and advantages: As described before, conventional solid dies for flat wire coating have a problem in which an insulation varnish applied on the rounded corners of a flat wire conductor is prone to flow into the flat surfaces thereof. And, this is probably caused by a difference between the surface curvature of the varnish applied on the rounded corners and that of the varnish applied on the flat surfaces.
[0063] According to the present invention, in order to solve this problem, an insulation varnish is applied around a flat wire conductor in such a manner that regions having a maximum surface curvature larger than the maximum surface curvature of the varnish applied on the rounded corners of the conductor are intentionally and optimally formed in the applied varnish (these large curvature regions are actually depressions 36 created by the protrusions 33 , see later-described FIG. 11 ). These depressions 36 provide a varnish surface curvature difference larger than the difference between the varnish surface curvature on the rounded corners and the varnish surface curvature on the flat surfaces. This feature of the invention probably produces the following effects: Mass transfer into the above-described large curvature depressions caused by a surface curvature difference predominantly occurs rather than mass transfer from the varnish surfaces on the rounded corners to the varnish surfaces on the flat surfaces. That is, mass transfer from the varnish surfaces on the rounded corners can be retarded to some extent. As a result, an insulation varnish applied on a flat wire conductor can be baked before the varnish applied on the rounded corners of the conductor starts to deform.
[0064] Preferably, each protrusion 33 is positioned within a certain distance from a rounded corner 35 nearest to the protrusion 33 . More specifically, the distance L between each protrusion 33 and the nearest rounded corner 35 (see FIG. 10 for the precise definition of the distance L) is preferably equal to or shorter than the minimum curvature radius r of the nearest rounded corner 35 (i.e., L≦r). The height h of the protrusions 33 is properly sized based on the desired coating thickness, the number of coatings, and other factors. For example, the height h is preferably from 50% to 90% of the gap t between the die hole 32 and the flat wire conductor 20 , and more preferably from 50% to 75%. The cross sectional area of the protrusions 33 is properly sized based on the desired total coating thickness and other factors.
[0065] FIG. 11 is a schematic illustration showing a cross sectional view of an example of a flat wire covered with an insulation coating by using an invented solid die. As illustrated in FIG. 11 , just after the varnish application, an insulation varnish 23 is evenly applied around a flat wire conductor 20 except for the depressions 36 caused by the protrusions 33 . On the other hand, after the baking, the depressions 36 disappear and an insulation coating 24 having a uniform thickness (e.g., 20 μm) is formed around the entire surface of the conductor 20 .
[0066] As has been described, the coating portion of the invented solid die for flat wire coating has a plurality of inwardly projecting protrusions on its inner wall. This configuration enables an insulation coating having a uniform thickness to be controllably formed around a flat wire conductor. Also, according to the invention, the coating thickness on each flat surface of a flat wire conductor can be independently adjusted by changing the height of the protrusions formed on the corresponding die hole surface. In view of various specifications of enameled flat wires, it is preferable that the protrusions on at least two of the four flat inner surfaces of the coating portion of an invented solid die have the same height (or, the highest heights of the protrusions on at least two of the four flat inner surfaces are the same).
[0067] FIG. 12 is a schematic illustration showing a cross sectional view of another example of a flat wire covered with an insulation coating by using an invented solid die. As illustrated in FIG. 12 , just after the varnish application, the insulation varnish 23 applied on three flat surfaces of the flat wire conductor have the same thickness, but the varnish 23 applied on the other flat surface has a thicker thickness. Similarly to the FIG. 11 varnish application, the varnish applied on each flat surface has the depressions 36 . Also, the flat wire conductor 20 did not suffer from any twisting. After the baking, the depressions 36 disappear similarly to the FIG. 11 case. As a result, around the flat wire conductor 20 is formed an insulation coating 24 having the same desired thickness (e.g., 20 μm) on three of the flat surfaces and a desired thicker thickness (e.g., 100 μm) on the other surface. Such an enameled flat wire as illustrated in FIG. 12 can be formed by using an invented solid die 30 in which the protrusions 33 on three flat inner surfaces 34 of the coating portion have the same height and the protrusions 33 on the other surface 34 has a higher height.
Examples
[0068] The present invention will be more specifically described below by way of examples. However, the invention is not limited to the specific examples below.
[0069] Two types of insulation coatings of a designed thickness of 20 μm were formed around a flat wire conductor having a cross section of 1.0 mm×5.0 mm. The insulated flat wire of Comparative Example 1 was formed by applying an insulation varnish around the flat wire conductor using a conventional solid die (see, e.g., FIG. 3 ) and by baking it. The insulated flat wire of Example 1 was formed by applying an insulation varnish around the flat wire conductor using an invented solid die (see, e.g., FIG. 8 ) and by baking it.
[0070] The thickness distribution of each insulation coating after the baking was measured by optical microscopy. The breakdown voltage of each enameled flat wire was measured according to Method B of JIS C 3003: 1999 (Methods of test for enameled wires). These results are summarized in Table 1. The above thickness distribution measurement was conducted as follows: Each enameled flat wire was transversely cut at five positions. Then, for each cut surface, the coating thickness was measured on eight different points of the flat surfaces of the flat wire conductor and on four different points of the rounded corners. The breakdown voltage of each example given in Table 1 was determined by averaging the breakdown voltages measured on ten specimens.
[0000]
TABLE 1
Coating thickness distribution and measurement
results of breakdown voltage of coating.
Coating Thickness
On Flat
Difference between
Surface
On Rounded
Max and Min
Breakdown
(μm)
Corner (μm)
Thicknesses (μm)
Voltage (kV)
Comparative
15-26
12-13
14
3.26
Example 1
Example 1
20-25
23-24
5
4.71
[0071] As is apparent from Table 1, in the conventional coating of Comparative Example 1, the coating is thinner on the rounded corners of the conductor and is thicker on part of the flat surfaces (clearly indicating the formation of a dog-bone surface along and near the rounded corners). The thickness difference between the thickest and thinnest points was as large as 14 μm. By contrast, in the invented coating of Example 1, the difference between the resulting thickness and the designed thickness is smaller on both regions (on the rounded corners and on the flat surfaces). And, the thickness difference between the thickest and thinnest points is as small as about ⅓ of that of the conventional coating. Also, the breakdown voltage of the enameled wire of Example 1 is improved to about 1.4 times that of the enameled wire of Comparative Example 1.
[0072] The results described above demonstrate that, by using the invented solid die for flat wire coating, the entire surface of a long flat wire conductor can be stably coated with an insulation coating having, on each straight side of the conductor, a uniform desired thickness without any undesirable significant local thickening/thinning. In addition, an insulation coating having the features just described above can be formed by both vertical and horizontal coating apparatuses employing the invented solid die.
[0073] Although the invention has been described with respect to the specific embodiments for complete and clear disclosure, the appended claims are not to be thus limited but are to be construed as embodying all modifications and alternative constructions that may occur to one skilled in the art which fairly fall within the basic teaching herein set forth. | There is provided an enameled flat wire, in which a flat wire conductor having a rectangular cross section composed of four flat surfaces and four rounded corners has an enamel coating with a predetermined thickness for electrical insulation. In the enameled flat wire, a difference in a thickness of the enamel coating on the flat surfaces between a maximum thickness and a minimum thickness is equal to or less than 25% of the predetermined thickness. | 2 |
RELATED APPLICATION DATA
[0001] This application is a continuation-in-part of each of:
[0002] 1) U.S. patent application Ser. No. 11/306,530, filed Dec. 30, 2005, entitled “Heat pipes utilizing load bearing wicks”, hereby incorporated by reference
[0003] 2) U.S. patent application Ser. No. 11/306,529, filed Dec. 30, 2005, entitled “Perforated heat pipes”, hereby incorporated by reference
[0004] 2) U.S. patent application Ser. No. 11/307,051, filed Jan. 20, 2006, entitled “Process of manufacturing of spongy heat pipes”, hereby incorporated by reference
FIELD OF INVENTION
[0005] This invention presents novel fastener design that embeds integral heat pipe structure throughout its volume. The fastener this way executes two functions: (i) securing components of a construction or an assembly, and (ii) efficiently transferring significant heat fluxes between the components.
[0006] Heat pipes and similar devices that utilize phase transitions of liquids and are essentially use heat pipe principles were used vastly in engineering of engines, motors, boilers, ovens, exhausts, and many other apparatuses that encounter significant density of generated heat energy. These devices are used in two ways: (i) they either integrated into design of the apparatus, or (ii) attached to the apparatus to establish heat link with another body. In either case heat pipe itself does not bear primary mechanical load and additional fastening structures establish mechanical fastening of the apparatus.
[0007] Traditional heat pipes are limited in their mechanical strength, as by design, they are hollow structures usually shapes as a pipe or a ribbon. Ribbon geometry does not provide significant shape stability and commonly uses for flexible designs. The pipe shape does not allow for convenient fastening and always requires additional fasteners and hardware to perform its operations.
DETAILED DESCRIPTION
[0008] This invention creates fasteners that provide significant mechanical strength and powerful heat transfer capacity. Its preferred embodiments show rigid design and shock dampening design. Invention utilizes benefits of two prior inventions Ser. No. 11/306,529 and Ser. No. 11/306,530 that disclose load bearing design of heat pipes and perforated or sponge like heat pipe design. It also relies on production method disclosed in invention Ser. No. 11/307,051.
[0009] These disclosures enable creation of arbitrary shaped heat pipe type devices that unlike traditional heat pipes reveal significant surface area. This invention employs these devices and embeds them into volume of a solid substance. In first preferred embodiment this substance is high temperature silicone rubber.
[0010] Alternatively a plurality of small discontinuous heat pipes or similar devices can be used in a similar way (term heat pipe stands for a sealed volume containing at least a mix of a liquid and its vapors). They can be poured together in ordered or unordered fashion and solidified/united by means of a solid substance via molding, laminating or other process. Resulting device will have the same mechanical and slightly inferior thermal characteristics yet sufficiently similar to consider it within the scope of this invention.
[0011] FIG. 1 shows an example of shock absorber for combustion engine. It is designed to interface directly with wall of combustion chamber (cylinder). Construction material is sponge like heat pipe molded with high temperature silicone rubber into desired shape. Bolted connections are used to attach cylinder block on one side and chassis of a machine on the other side. Broken view shows inner volume of the part. It is occupied by unordered mesh of heat pipe where all voids are filled with silicone rubber. Such a construction has high mechanical strength that allows direct bolt connections and sufficient elasticity that reduces chassis vibrations caused by the engine.
[0012] The same geometry if executed as a standard heat pipe will have poor mechanical strength and would collapse under load of bolts and the engine weight.
[0013] Second preferred embodiment uses electroplated aluminum and alumina particles composite instead of molding compound. Final structure resembles porous metal but have branches of the heat pipe embedded in it. Resulting part has high tensile and compression strength and light weight, yet its thermal conductivity exceeds one of graphite fibers. Implemented technique allows for high structural loads on the part due to its advanced geometry. Parts like can be used as a fasteners and structural elements in jet engines, gas turbines, electric motors etc.
[0014] FIG. 2 show implementation of this embodiment in micro motor applications. High speed micro electric motors can provide significant specific power up 100 times exceeding those of large industrial motors, but this power quickly overheat them. Invented fastener provides no weight overhead comparing with ordinary fasteners, yet it sinks more heat than any ordinary heat sink. Chassis of the craft dissipate this heat flux by passive heat transfer. Implementing similar approach with regular heat pipe solution would create weight overhead caused by weight of a heat pipe and mounting hardware.
[0015] Discontinued heat pipes can be produced by cutting a long capillary heat pipe onto plurality of short segments while sealing their ends. This discontinued segment can be as narrow as 0.8 mm or even less and 5 mm to several centimeters long. These fragments can form a felt like structure or be parked in yarns or other ordered layouts. For subject of this invention it is not essential whether a perforated- or spongy-heat pipe or plurality of discontinued heat pipes employed inside the part of described embodiments.
[0016] This invention provides great usability and functional benefits to high energy density engineering designs ranging from micro-robotics and mobile electronics to industrial equipment and aero-space.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 shows an example of harness with high mechanical strength and exceptional thermal conductance. Part of exterior finish is shown as removed to illustrate inner fibrous composition. Each of shown fibers is micro heat pipe.
[0018] FIG. 2 shows an example of harness that simultaneously plays role of a radiator. Monolithic design was machined from block of material with embedded micro heat pipes. | Invention disclosures novel design of structural components and fasteners that in addition to sound mechanical strength reveal excellent thermal characteristics, which allows using them as super efficient heat sinking/management solutions. | 5 |
RELATED APPLICATIONS
[0001] The present application claims the benefit under 35 USC 119(e) of U.S. provisional application 60/542,843 filed on Feb. 10 th , 2004, and PCT application PCT/IL05/00154 also known as WO2005/074378, the disclosure of which are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates in general to a device and method for substantially reducing the caloric efficiency of the digestive tract by capturing food being digested in the stomach and/or anywhere else in the GI tract, into entrapping members; moving the entrapping member containing said food down the GI tract, thus excluding at least part of the food intake from being absorbed in the small intestine and further down the GI tract.
BACKGROUND OF THE INVENTION AND RELATED ART
[0003] Obesity is a chronic disease due to excess fat storage, a genetic predisposition, and strong environmental contributions. This problem is worldwide, and the incidence is increasing daily. There are medical, physical, social, economic, and psychological comorbid conditions associated with obesity. There is no cure for obesity except possibly prevention. Non-surgical treatment has been inadequate in providing sustained weight loss. Currently, surgery offers the only viable treatment option with long-term weight loss and maintenance for the morbidly obese. Surgeries for weight loss are called bariatric surgeries. There is no one operation that is effective for all patients. Gastric bypass operations are the most common operations currently used. Because there are inherent complications from surgeries, bariatric surgeries should be performed in a multidisciplinary setting. The laparoscopic approach is being used by some surgeons in performing the various operations. The success rate—usually defined as >50% excess weight loss that is maintained for at least five years from bariatric surgery—ranges from 40% in the simple to >70% in the complex operations. The weight loss from surgical treatment results in significant improvements and, in some cases, complete resolution of comorbid conditions associated with obesity. Patients undergoing surgery for obesity need lifelong nutritional supplements and medical monitoring.
[0004] It is accepted that patients suffering from obesity are at a substantially increased risk of medical ailments and a range of diseases, including: Type II diabetes, heart disease, stroke, high blood pressure, high cholesterol, certain cancers, and other disorders. Furthermore, patients suffering morbid obesity have life expectancy that is significantly reduced, by at least ten to fifteen years.
[0005] For patients suffering from extremely severe obesity (morbid obesity), i.e. for patients whose weight exceeds the ideal weight by at least 50 kilograms, for example, it is absolutely essential to operate surgically on such patients in order to avoid not only a series of health problems that stem from such obesity, but also to avoid certain and imminent death of such patients.
[0006] It has also been observed that treatment based on a severe diet combined with a series of physical exercises associated with a change in behavior, in particular eating behavior, are relatively ineffective in such cases of morbid obesity, even though such methods of treatment are the most healthy.
[0007] Methods that have been used in the prior art to treat obesity include gastric bypasses and small-bowel bypasses such as described in U.S. Pat. No. 6,558,400 and U.S. Pat. No. 6,543,456. The number of these bariatric surgeries has skyrocketed from 40,000 per year back then to 120,000 in 2002. Many complications are associated with these procedures. Many patients have suffered serious side effects and regret having had it.
[0008] Other methods aim at reducing the effective volume of the stomach to induce a satiety feeling by the patient and hence reducing the calorie intake per meal.
[0009] One such method is the stapling of portions of the stomach has also been used to treat obesity, such as described in U.S. Pat. No. 5,345,949. This includes both vertical and horizontal stapling and other variations trying to reduce the size of the stomach or make a small stoma opening. Many problems have been associated with the use of staples. First, staples are undependable; second, they may cause perforations; and the pouch or stoma opening formed by the staples becomes enlarged over time making the procedure useless.
[0010] Another method that has been developed is the placement of an inflatable bag or balloon into the stomach causing the recipient to feel “full”. Such a procedure has been described in the patent to Garren et al U.S. Pat. No. 4,416,267. The balloon is inflated to approximately 80% of the stomach volume and remains in the stomach for a period of about three months or more. This procedure, although simple, has resulted in intestinal blockage, gastric ulcers, and even in one instance, death and fails to address the problems of potentially deleterious contact with the gastric mucosa which can result from leaving an inflated bag in the stomach for an extended period of time. Moreover, it also failed to produce significant weight loss for long periods of time.
[0011] Yet another method employs the placement of a band around a portion of the stomach thereby compressing the stomach and creating a stoma opening that is less than the normal interior diameter of the stomach for restricting food intake into the lower digestive portion of the stomach. Kuzmak et al in U.S. Pat have described such a band. U.S. Pat. No. 4,592,339. It comprises a substantially non-extensible belt-like strap, which constrictively encircles the outside of the stomach thereby preventing the stoma opening from expanding. Kuzmak et al also describe bands, which include a balloon-like section that is expandable and deflatable through a remote injection site. The balloon-like expandable section is used to adjust the size of the stoma opening both intra-operatively and post-operatively.
[0012] Complications have been observed with both inflatable and non-inflatable gastric bands. In particular, obstruction of the stoma from edema and migration of the band has been observed. Such edema-caused obstruction of the stoma may be due to excessive vomiting. In these cases, the stoma must be enlarged either by deflating the expandable portion of a band or by removing the band altogether.
[0013] Yet another method is to impose satiety. U.S. Pat. No. 6,677,318, describing a swellable sponge-like structure. These structures are swallowed by the patient being collapsed inside a capsule. The capsule dissolves in the stomach and the polymer structure with super absorbing characteristics; absorb the gastric juices, which cause the structure to swell considerably. This patent aims to reduce food intake by causing the recipient to feel “full”, yet the absorbed content of the sponge is finally digested.
[0014] Lipase inhibition as a mean for reducing lipid intake is well known in the art, the major draw back is the oily stool as a side effect. To overcome this side effect, polymers capable of absorbing lipids where introduce, as in U.S. Pat. No. 4,432,968, but as the absorption is reversible and shifted backwards as a result of bile salt emulsifier, the overall entrapment was quite poor.
[0015] In order to overcome the a forth mentioned drawbacks, the present invention relates on a lipid absorption polymer having an prolonged equilibrium period in the range of 4-8 hours so as to keep the absorption step active during the relevant period in the digestion tract.
[0016] It is then the object of this invention to overcome these and other deficiencies described above.
SUMMARY OF THE INVENTION
[0017] The invention seeks to provide a successful and non-invasive alternative to existing approaches for controlling obesity.
[0018] The invention objective is to substantially reduce the caloric efficiency of the digestive tract by capturing food being digested in the stomach and/or anywhere else in the GI tract into entrapping members; moving the entrapping member containing the entrapped food ingredients down the gastrointestinal tract, thus excluding at least part of the entrapped food from being absorbed in the small intestine.
[0019] Another objective of this invention is to introduce a lipid absorption polymer having an prolonged equilibrium period in the range of 4-8 hours so as to keep the absorption step active during the relevant period in the digestion tract.
[0020] Another objective of this invention is to interfere with the micelles formation and capture the free lipids contained within
[0021] Another objective of this invention is to provide a delivery system of the material via means of compressing the material so that it takes less space in the intake, and when the capsule, for example, opens up or dissolves, the individual particles of the material expand to accommodate the captured liquids.
[0022] In one embodiment, the device is comprised of a capsule system for oral delivery. The capsule system is comprised of an external capsule made of gelatin—as an example that dissolves in accordance with a temporal preset, which allows the food intake to be at least partially fluidic. The capsule system is further comprised of an internal permeable bag having a structure such as meshed, woven or fibers, made of disintegrable material such as gelatin for example, which bag contain expandable, super absorbent beads, which dry beads are larger than the pores of the bag, which bag is inflatable. When the bag comes in contact with the fluidic content of the stomach, fluids penetrate into the bag. The fluids are absorbed by the expandable, hydrogel beads enclosed. These beads expand partially or until they reach the absorption capacity limit. Optionally, the internal bag further contains a coating capsule, which dissolves at this time and coats the expandable beads, to seals and protects them from disintegration or prevent leakage of entrapped liquid, throughout their journey out of the GI tract.
[0023] For the sake of clarity, a capsule is a sealed container and a bag is a permeable containers.
[0024] In other embodiments, the external capsule contains folded mechanical structures, which open up to captures some of the stomach content and protects them from disintegration throughout their journey through and out of the GI tract.
[0025] Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] The present invention will become more fully understood from the detailed description given herein below and the accompanying drawings, which are given by way of illustration only and thus not limitative of the present invention.
[0027] FIG. 1 is a view of the assembled device.
[0028] FIG. 2 a is a view of the external capsule.
[0029] FIG. 2 b is a view of the internal bag.
[0030] FIG. 2 c is a view of an expandable bead.
[0031] FIG. 2 d is a view of a coating capsule.
[0032] FIG. 3 illustrates a basic embodiment of this invention depicting an outer capsule containing super absorbent expandable beads.
[0033] FIG. 4 a illustrates of the capsule system entering the stomach at t 1 .
[0034] FIG. 4 b illustrates the external capsule dissolving at t 2 .
[0035] FIG. 4 c illustrates the expandable beads expanding as they absorb stomach fluids.
[0036] FIG. 4 d illustrates the expandable beads reaching the size limits of the internal bag at t 4 .
[0037] FIG. 4 e illustrates the rupture of the coating capsule at t 4 .
[0038] FIG. 4 f illustrates the internal capsule dissolving at t 5 .
[0039] FIG. 4 g and FIG. 3 h illustrate the draining stage of the coated at t 6 .
[0040] FIG. 5 is a temporal illustration of a full cycle of the process.
[0041] FIGS. 6 a - d illustrates another embodiment of the invention.
[0042] FIGS. 7 a - c illustrates another embodiment of the invention.
[0043] FIGS. 8 a - c illustrates yet another embodiment of the invention.
[0044] FIG. 9 illustrates an embodiment for loading the force into the small structures.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0045] Before explaining embodiments 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 the arrangement of the components set forth in the following description or illustrated in the drawings.
[0046] Unless otherwise defined, all 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. The materials, methods, and examples provided herein are illustrative only and not intended to be limiting.
[0047] In accordance with one basic embodiment of the present invention, illustrated in FIG. 3 , the device is in a form of a pill comprises an outer capsule 200 made of Gelatin for example, which capsule 200 is at least partly filled with cross-linked polymer beads, such as Hydrogels, supper absorbent polymers, cross-linked polymers, known in the art, which beads having a diameter in the range of microns to few mm and are made of non toxic and non digestible polymer and are capable of absorbing fluids at a ratio of at least 5:1 (W/W), (liquid\bead) by diffusion, osmotic force, ionic interaction, and\or capillary force, and\or magnetic force, or other physic-chemical mechanism, such as polyacryl amid derivatives, which absorbing beads may also act as ion exchanger, exclusion gel such as a cross-linked polydextran (or possibly Cellulose Ethers like material), which beads optionally may also contain functional groups that improves permeability when the ambient is acidic (low pH—at the stomach), yet the permeability is reduced when the ambient pH is neutral or basic (small intestine).
[0048] In practice, the pill is ingested, and the capsule 100 dissolves at a temporal preset, beads 300 which are now in contact with the content of the food being digested, absorbs caloric enriched liquid and swells. Next the beads along with content of the stomach 10 are moved into the small intestine, where the entrapped content of the beads are practically not involved in the digestion and absorbing steps in the intestine. It is plausible to design the beads such that they will continue to absorb digested food in the small intestine and further down the GI tract.
[0049] In another embodiment, similar to the first embodiment, the beads are pre coated or pre absorbed by a composition capable of forming at least a partial nutrient barrier on small intestine. The composition helps further to reduce the absorption of food in case of leaking from the bead.
[0050] FIG. 1 is a view of the assembled capsule system. It comprises an external capsule 100 which can be made of a biocompatible material such as gelatin, an internal bag 200 which can be made from gelatin with a net like structure, absorbing beads 300 which can be made from Hydrogels and coating capsule(s) 400 .
[0051] FIG. 2 a illustrates the opened external capsule, which opens into two halves 201 and 202 at time t 2 (see FIG. 5 ). It cans also dissolve with control thickness or any other known technique.
[0052] FIG. 4 a illustrates the assembled capsule being swallowed by the patient at time t 1 (see FIG. 5 ) which is a while after he started his meal at time t 0 (see FIG. 5 ). FIG. 2 b is a view of the internal bag 200 , FIG. 2 c is a view of an expandable bead 301 and FIG. 2 d is a view of a coating capsule 400 .
[0053] FIG. 4 b illustrates the dissolution of the external capsule in the stomach 10 at time t 2 . At this time the super absorbing expandable beads 300 are exposed to the stomach 10 fluids and start absorbing them, as illustrated in FIG. 4 c and continue at time period t 3 (see FIG. 5 ).
[0054] Optionally, after the expandable beads 300 fill out the space allowed by the internal bag 200 , as illustrated in FIG. 4 d , they press against the coating capsule(s) 400 . This triggers at time t 4 (see FIG. 5 ) the rupture, as illustrated in FIG. 4 e , or dissolution of the coating capsule(s) 400 , which contains an agent that coats and seals (see FIG. 4 f ) all the expandable beads such that they and their content remains untouched throughout their migration down the GI tract.
[0055] Once all the expandable beads 300 are coated, at time t 5 (see FIG. 5 ), the internal bag dissolves, all the expandable beads are free to move about the GI tract, at time period t 6 (see FIG. 5 ), and they are drained untouched through and out of the GI tract, as illustrated in FIGS. 4 g and 4 h . The expandable beads 300 dissolve after a preset number of days, in case they were not able to clear out of the GI tract. In another option, the patient drinks a liquid that dissolves expandable beads 300 .
[0056] Thus the content of the expandable beads 300 which contains ingested food remains untouched, is not digested and absorbed by the body and hence reduces the calorie efficiency of the meal.
[0057] In another embodiment of this invention, time t 5 (see FIG. 5 ), when the internal bag 200 dissolves and the expandable beads 300 are free to move about the GI tract, occurs only after the fed mode of the stomach 10 is finished, and the stomach 10 goes into its maintenance mode.
[0058] I another embodiment (not shown) the fluids pass on their way to the super absorbable beads through a filter which is wide on the outer side and narrow in the inner side. This makes it easy for the fluids the flow inward the beads and hard to flow back.
[0059] In yet another embodiment of this invention, a polymer capable of absorbing lipid having an prolonged equilibrium period in the range of 4-8 hours so as to keep the absorption step active during the relevant period in the digestion tract, is provided. One such polymer for example is Polypore, having high absorption ratio of 13 gr lipid to 1 gr polymer
[0060] Another embodiment of the present invention is to interfere with the micelles which are necessary for the lipid digestion activity. The purpose of the polymer is to disassemble the micelles and extract the lipids. Such a polymer is, for example, isss Gantrez® series, especially Gantrez 225 and Gantrez 425.
[0061] So when a mixture of Polypore and Gantrez are introduced to the small intestine, the Gantrez will interfere with the micelle formation equilibrium, and the polypore will absorb the free lipids without the highly competitive back extraction mechanism.
[0062] Another embodiment of this invention is illustrated in FIGS. 6 a - 6 d in this embodiment the inner bag is in the form of a folded basket 202 which contains a stack of spheres 500 each of which is split into to halves 501 and 502 which are connected by a spring like connection 503 that the force embedded in it will close up the spheres to the poison 504 in a relaxed mode. When the external capsule 100 dissolves, the force embedded in the stacked up halve spheres 500 will cause the optional basket 202 to open up optionally locked into the position illustrated in FIG. 6 d . This allows the half spheres to close up to position 504 which scoops up the food being digested while closing up. The sphere 504 is now small enough to leave the basket 202 through the opening 203 , being pushed by the next pair of half spheres. The last pair of half spheres in the stack may remain in the basket 202 , which dissolves after a preset time and clears out down the GI tract. The optional basket 202 is designed to avoid the possibility that the closing sphere will harm the stomach 10 inner walls. The spheres 500 are of a size appropriate to be able to travel through the GI tract. The closed spheres are made of a substantially ingestible biocompatible material and remain closed and untouched through the journey down and out of the GI tract. The spheres 500 dissolve after a preset number of days, in case they were not able to clear out of the GI tract. In another option, the patient drinks a liquid that dissolves spheres 500 .
[0063] Another embodiment of this invention is illustrated in FIGS. 7 a - 7 c . In this embodiment, the capsule is filled up with number of folded stent like structures 600 . When the external capsule 100 dissolves, a force will cause the stents 600 to open up and lock into the position illustrated in FIG. 7 c . The force can be embedded in the structures 600 , apply via external or internal spring (not shown) or generated internally or externally via chemical reaction with the stomach 10 content. While stents 600 open up inside the stomach 10 they will suck up some of the content into the stents. The stents 600 are built such that they have entry holes 604 through which the content is sucked up. Optionally, entry holes 604 are equipped with a directional valve such that the stomach 10 content can only enter into the stents but can not escape. The size of the opened stents 600 is designed to be able to travel through the GI tract. The stents are made of a substantially ingestible material and remain closed and untouched throughout their journey down and out of the GI tract. The folded structures 601 , 602 , 603 can also be polymer beads and the force applied to them before delivery to compress the beads substantially so that they open inside the GI tract to capture various liquids. One such polymer, for example, is Polypore, having high absorption ratio of 13 gr lipid to 1 gr polymer and high ratio of its free form volume to its compressed form volume.
[0064] In another embodiment the force (such as spring force or elastic force) is being loaded into the small structures 700 before using the capsule. FIG. 9 shows a device 800 for compressing the small structures 700 and encapsulating them to form the pill to be swallowed. Turning the handle 802 in direction 806 moves the bar 804 in direction 808 . The capsule half 101 is pushed towards the second half 102 and the small structures 700 are compressed. This will overcome the possibility that the force will deteriorate over time.
[0065] Another embodiment of this invention is illustrated in FIGS. 8 a - 8 c . In this embodiment, the capsule is filled up with a number of folded structures 700 . When the external capsule 100 dissolves, the force embedded within the structures will cause the structures 700 to open up into the position 702 illustrated in FIG. 8 c . The force can be embedded in the structures 700 , in the manufacturing process by taking a semi rigid structure and forcing it into a collapsed form by applying pressure. The kinetic energy stored in the structures 700 will be used to restore the structures into their natural form once the capsule 100 has opened up. This force is designed so that it can over come the pressure inside the stomach 10 . While structures 700 open up inside the stomach 10 they will suck up some of the content into the structures 700 . The structures 700 are made up such that they have entry holes 703 through which the content is sucked up. Optionally, entry holes 703 are equipped with a directional valve such that the stomach 10 content can only enter into the structures 700 but cannot escape. The size of the opened stents 700 is designed to be able to travel through the GI tract. The full structures 700 are made of a substantially ingestible material and remain closed and untouched throughout the journey down and out of the GI tract.
[0066] In another embodiment the folded structures are polymer beads and the force applied to them before delivery to compress the beads substantially so that they take less space on the intake but open inside the GI tract to capture various liquids. One such polymer, for example, is Polypore, having high absorption ratio of 13 gr lipid to 1 gr polymer and high ratio of its free form volume to its compressed form.
[0067] The invention being thus described in terms of several examples and embodiments, 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 as would be obvious to one skilled in the art are intended to be included within the scope of the following claims. | Devices and methods for substantially reducing the caloric efficiency of the digestive tract by capturing food being digested in the stomach 10 and/or anywhere else in the gastrointestinal (GI) tract, absorbing or encapsulating the captured food into multiple capturing members and moving such multiple capturing members containing the ingestible encapsulated food down the GI tract, practically out of reach of the GI absorption organs, thus excluding the entrapped ingredients from being involved in the digestion and\or absorption process. The device is designed for oral delivery. The system can be comprised of liquid, food bars or a capsule system. The capsule system is comprised of an external capsule that dissolves in accordance with a temporal or ph dependent preset, which allows the food intake to be at least partially fluidic. The capsule system is further comprised of a mechanism designed to capture and isolate a portion of the food being digested. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of Korean Patent Application No. 2007-0107256, filed on Oct. 24, 2007 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference.
BACKGROUND
[0002] 1. Field
[0003] The present invention relates to a method for manufacturing a polyimide carbon nanofiber electrode and/or a carbon nanotube composite electrode, and a CDI apparatus using the electrode. More specifically, the present invention relates to a method for manufacturing a flat plate electrode from polyimide carbon nanofibers without using any binder and a CDI apparatus using the flat plate electrode.
[0004] 2. Description of the Related Art
[0005] Generally, carbon fibers and activated carbon fibers are classified into polyacrylonitrile (PAN)-based, acryl-based, pitch-based, phenol-based carbon fibers, etc., depending on the starting material to make the fibers.
[0006] Carbon fibers are prepared using wet-, melt- or dry-spinning that employs melting PAN-based, acryl-based, pitch-based, or phenol-based polymers, etc., at ambient temperature or a high temperature and then drawing or pulling out fibers from the molten polymers at a physical pressure.
[0007] Meanwhile, activated carbon fibers are prepared by activating carbon fibers with water vapor, carbon dioxide, KOH, ZnCl 2 , etc.
[0008] The carbon fibers prepared by these traditional spinning methods almost have a relatively high diameter of about 5 to about 50 μm. Due to the high diameter, the carbon fibers have a low flexural strength and are not thus easy to apply to compress processing.
[0009] In recent years, electrostatic spinning (also called “electrospinning”) has been used, which is a method capable of preparing ultrafine fibers from polymers via an electrostatic force, in contrast to the spinning methods depending upon a physical force. In accordance with the electrostatic spinning, a polymeric solution, to which a high-voltage electric field is applied, is sprayed to prepare fibers. More specifically, positive (+)-charged ions in the polymeric solution are discharged from an ejector and then adsorbed on a negative (−)-charged electrode collector to produce a nanofiber web.
[0010] The preparation of carbon nanofibers or activated carbon nanofibers using the electrostatic spinning is carried out by dissolving PAN, pitch or phenol in a solvent such as metacresol, subjecting the resulting solution to electrostatic spinning to prepare carbon nanofibers, and stabilizing, carbonizing or activating the carbon nanofibers.
[0011] For example, Korean Patent Laid-open Publication No. 10-2003-0089657 discloses preparation of carbon fibers and activated carbon fibers from polyamic acid (PAA) by electrostatic spinning and its applications to electric double layer supercapacitor electrodes.
[0012] More specifically, the afore-mentioned publication paper discloses preparation of polyimide fibers having nanometer-scale diameters with superior electrical conductivity by electrostatic spinning, preparation of carbon nanofibers and activated carbon nanofibers from the polyimide fibers, and the use thereof as electric double layer capacitor electrode materials.
[0013] Polyimide is a highly thermal and chemical resistant polymer having an imide group in the repeat units, imide monomers. In spite of these advantages, polyimide has limited applications. The reason is that polyimide has poor processability into a specific shape due to solvent-insolubility and heat resistance (flame resistance).
[0014] Accordingly, polyimide processing is carried out by processing polyimide into a specific shape in a PAA precursor solution using a polar solvent and converting the polyimide into imide using a thermal or chemical method.
[0015] Thus, the invention disclosed in the publication paper suggests a method for preparing nanometer-scale ultrafine carbon nanofibers and activated carbon nanofibers with a high specific surface area by electrostatic-spinning polyimide with superior electrical conductivity, and applications thereof to an electric double layer capacitor electrode without using any binder.
SUMMARY
[0016] However, these conventional methods for preparing polyimide by electrostatic spinning and manufacturing for a supercapacitor electrode material from activated carbon nanofibers have disadvantages in that electrostatic spinning cannot be smoothly performed due to a high viscosity of spinning solution, the diameters of carbon nanofibers cannot be controlled via optimization of complicated conditions, and the surface area of the prepared carbon nanofibers cannot be increased due to their relatively large diameters (i.e., about 400 nm).
[0017] In addition, when the conventional supercapacitor electrode material is utilized in a CID apparatus, the supercapacitor electrode cannot efficiently exert its functions on the CID apparatus due to the difference in use conditions between the capacitor and the CID apparatus.
[0018] In attempts to solve the problems of the prior art, one object of the present invention is to provide a method for manufacturing a polyimide carbon nanofiber electrode and/or a carbon nanotube composite electrode, wherein the diameters of carbon nanofibers can be lessened by optimizing the electrostatic spinning in order to improve spinnability.
[0019] Another aspect of the present invention is to provide a method for manufacturing a polyimide carbon nanofiber electrode and/or a carbon nanotube composite electrode, capable of improving electrical conductivity.
[0020] Another aspect of the present invention is to provide a CDI apparatus capable of improving ion collection capability by using the polyimide carbon nanofiber electrode and/or the carbon nanotube composite electrode.
[0021] Therefore, in accordance with one aspect of the invention, a method to manufacture a carbon fiber electrode comprises: synthesizing polyamic acid (PAA) as a polyimide (PI) precursor from pryomellitic dianhydride (PMDA) and oxydianiline (ODA) as monomers and triethylamine (TEA) as a catalyst; adding dimethylformamide (DMF) to the polyamic acid (PAA) solution to prepare a spinning solution and subjecting the spinning solution to electrostatic spinning at a high voltage to obtain a PAA nanofiber paper; converting the PAA nanofiber paper into a polyimide (PI) nanofiber paper by heating; and converting the polyimide (PI) nanofiber paper into a carbon nanofiber (CNF) paper by heating under an Ar atmosphere.
[0022] The method may further comprise: activating the CNF paper by acid- or base-treatment to increase the surface area of the CNF paper and control the distribution of pores in the CNF paper; and subjecting the CNF paper to acid-treatment and heat-treatment to distribute mesopores into the CNF paper.
[0023] An amount of the TEA catalyst contained in the spinning solution may be 1 to 5% by weight.
[0024] The content of the PAA polymers contained in the spinning solution may be 17 to 20% by weight.
[0025] The conversion of the polyimide (PI) nanofiber paper into a carbon nanofiber (CNF) paper may further include: pressurizing the polyimide (PI) nanofiber paper to increase electrical conductivity of the carbon nanofiber (CNF) paper.
[0026] The acid-treatment may be carried out by treating the CNF paper with nitric acid and the heat-treatment may be carried out by heating the CNF paper at 400° C.
[0027] The capacitive deionization (CDI) apparatus according to the present invention comprises the carbon fiber electrode manufactured according to the method.
[0028] In accordance with another aspect of the invention, a method to manufacture a carbon nanotube composite electrode comprises: sequentailly adding carbon nanotubes (CNTs) and triethylamine (TEA) as a catalyst to pryomellitic dianhydride (PMDA) and oxydianiline (ODA) as monomers to synthesize a polyamic acid/carbon nanotube (PAA/CNT) composite; subjecting the PAA/CNT composite spinning solution to electrostatic spinning to obtain a PAA/CNT nanofiber paper; converting the PAA/CNT nanofiber paper into a polyimide/carbon nanotube (PI/CNT) nanofiber paper by heating; and converting the PI/CNT nanofiber paper into a carbon nanofiber/carbon nanotube (CNF/CNT) composite by heating under an Ar atmosphere.
[0029] A content of the CNT in the CNF/CNT composite may be 0.001 to 50% by weight.
[0030] The method may further comprise: activating the CNF/CNT composite by acid- or base-treatment to increase the surface area of the CNF/CNT composite and control the distribution of pores in the the CNF/CNT composite; and subjecting the CNF/CNT composite to acid-treatment and heat-treatment to distribute mesopores into the CNF/CNT composite.
[0031] The method may further comprise: after the activation, subjecting the CNF/CNT composite to acid-treatment and heat treatment to distribute mesopores in the CNF/CNT composite.
[0032] The capacitive deionization (CDI) apparatus according to the present invention comprises the carbon nanotube composite electrode manufactured according to the method.
[0033] Additional aspects and/or advantages of the invention will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0034] These and/or other aspects and advantages of the invention will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:
[0035] FIG. 1 is a flow chart illustrating a method to manufacture a carbon fiber electrode according to a preferred embodiment of the present invention;
[0036] FIG. 2 is a view illustrating an electrostatic spinning apparatus used to manufacture the carbon fiber electrode according to the preferred embodiment of the present invention.
[0037] FIG. 3 is a graph showing a mean diameter of PAA fibers prepared by electrostatic spinning under the conditions that a content of PAA polymers in the spinning solution is kept constant and a TEA catalyst amount is varied;
[0038] FIG. 4 is a graph showing mean diameters of PAA nanofibers, PI nanofibers and carbon nanofibers prepared by electrostatic spinning under the conditions that a TEA catalyst amount is kept constant and a content of PAA polymers is varied;
[0039] FIG. 5 is a graph showing correlation between the molecular weight, voltage and flow rate obtained under optimum electrostatic spinning conditions, while constantly maintaining the amount of PAA polymers in the spinning solution in the manufacturing process of FIG. 1 ;
[0040] FIG. 6 is a graph showing a correlation between a diameter of carbon nanofibers according to the preferred embodiment of the present invention, an electrical conductivity and a pressure;
[0041] FIG. 7( a ) is an electron microscope image of PAA nanofibers prepared in accordance with a preferred embodiment of the present invention;
[0042] FIG. 7( b ) is an electron microscope image of PI nanofibers prepared in accordance with a preferred embodiment of the present invention;
[0043] FIG. 7( c ) is an electron microscope image of CNT nanofibers prepared in accordance with a preferred embodiment of the present invention;
[0044] FIG. 8 is a flow chart illustrating a method to manufacture a carbon nanotube composite electrode according to a preferred embodiment of the present invention; and
[0045] FIG. 9 is a schematic diagram illustrating a CDI apparatus comprising the carbon nanofiber electrode or the carbon nanotube composite electrode manufactured according to the present invention.
DETAILED DESCRIPTION OF EMBODIMENTS
[0046] Reference will now be made in detail to the embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The embodiments are described below to explain the present invention by referring to the figures.
[0047] FIG. 1 is a flow chart illustrating a method to manufacture a carbon fiber electrode according to a preferred embodiment of the present invention.
[0048] First, in order to synthesize polyamic acid (PAA) as a polyimide (PI) precursor, 4 g of oxydianiline (ODA) is dissolved in 20 g of dimethylformamide (DMF). After the resulting solution is allowed to stand at 5° C., 4.4 g of pyromellitic dianhydride (PMDA) is slowly added thereto over 30 minutes with stirring, to obtain the targeted polyamic acid (PAA).
[0049] In this embodiment, the weights of ODA, DMF and PMD are not intended to be restricted to the aforementioned specific values and are given for illustrating one example wherein a polyamic acid solution in which a weight ratio of ODA, DMF and PMD is approximately in the range of 4 20:4.4 is prepared.
[0050] After the solution is allowed to stand at − 5 ° C., triethylamine (TEA) as a catalyst is added thereto (S 10 ) and mixed until polymerization is completed. An amount of the TEA catalyst used herein is in the range of 1 to 5% by weight to control a molecular weight.
[0051] The PAA solution thus prepared is given as a colorless liquid. To the solution, is further added DMF to adjust the content of the PAA to 20 wt %, and thereby to obtain a PAA/DMF solution (referred to as a “spinning solution”) (S 20 ). The PAA/DMF solution is subjected to electrostatic spinning to obtain a PAA nanofiber paper (S 30 ).
[0052] FIG. 2 is a view illustrating an electrostatic spinning apparatus used to manufacture the carbon fiber electrode according to the preferred embodiment of the present invention.
[0053] As shown in FIG. 2 , the electrostatic spinning apparatus used in the present invention comprises a syringe 10 to inject a spinning solution and a cylindrical collector 20 covered with aluminum foil.
[0054] The syringe 10 used to inject the spinning solution has an inner diameter of 2 cm and a length of 10 cm. The syringe 10 is provided at an end with a nozzle 30 having an inner diameter 0.5 mm and is filled with a spinning solution 40 (PAA/DMF solution). The collector 20 and the nozzle 30 are spaced apart from each other at a distance of about 15 cm.
[0055] In the fabrication of the carbon fiber electrode according to the preferred embodiment of the present invention, electrostatic spinning is optimized to design a stable Taylor cone-jet by controlling a spinning voltage and a flow rate depending upon the PAA molecular weight and solid content (wt %) using the electrostatic spinning apparatus having the aforementioned structure.
[0056] In this embodiment, triethylamine (TEA) is used as a catalyst. The embodiment is different from conventional cases using no catalyst, in terms of the tissue structure of the electrospun carbon fibers. That is, in conventional cases using no catalyst, carbon fibers with non-uniform diameters in which beads are dispersed are obtained, and on the other hand, in the preferred embodiments of the present invention using the catalyst, carbon fibers with a uniform diameter are obtained, independent of the amount of the catalyst (not less than about 1 wt %).
[0057] FIG. 3 is a graph showing a mean diameter of PAA fibers prepared by electrostatic spinning under the conditions that a content of PAA polymers in the spinning solution is kept constant and a TEA catalyst amount is varied. FIG. 4 is a graph showing mean diameters of PAA nanofibers, PI nanofibers and carbon nanofibers prepared by electrostatic spinning under the conditions that a TEA catalyst amount is kept constant and a content of PAA polymers is varied.
[0058] The diameter of the spun nanofibers is varied dependent upon an amount of the catalyst used for the polymerization and a content (wt %) of PAA polymers in the spinning solution. When the content of the PAA polymers is maintained at 20 wt % and the amount of the TEA catalyst is sequentially varied to 1, 3 and 5 wt %, as shown in FIG. 3 , a mean diameter of the PAA fibers is gradually increased to 160 nm, 200 nm and 225 nm, respectively. When the catalyst amount is kept at 1 wt % and the PAA polymer content is varied in the range of 17 to 20 wt %, the PAA nanofibers prepared from the spinning solution, wherein the PAA polymer content is 18 wt %, had the smallest mean diameter of about 125 nm.
[0059] These experiment results ascertained that the lower the amount of the TEA catalyst, the smaller the mean diameter of the PAA nanofibers, and when the PAA polymer content is 18 wt %, the PAA nanofiber diameter is minimized. Accordingly, it may be considered preferable to make the amount of the TEA catalyst as low as possible in order to lessen the diameter of the PAA nanofibers. However, when the TEA catalyst amount is lower than 1 wt %, as mentioned above, rather, PAA nanofibers whose mean diameter is increased and which are non-uniform are obtained. Preferably, the diameters of PAA nanofibers are minimized by utilizing the TEA catalyst amount and the PAA polymer content of about 1 wt % and about 18 wt %, respectively.
[0060] FIG. 5 is a graph showing correlation between the molecular weight, voltage and flow rate obtained under optimum electrostatic spinning conditions, while constantly maintaining the amount of PAA polymers in the spinning solution in the manufacturing process of FIG. 1 .
[0061] As can be seen from FIG. 5 , under the condition that the amount of PAA polymers contained in the spinning solution is maintained at 20 wt %, the PAA molecular weight (lower horizontal axis) is varied dependent upon the catalyst amount (upper horizontal axis), and the PAA molecular weight affects the spinning conditions.
[0062] That is, as the molecular weight of the PAA polymers becomes smaller, the critical voltage of the electrostatic spinning decreases, and as the molecular weight of the PAA polymers becomes larger, the critical voltage gradually increases, and then reaches a limit voltage.
[0063] As may be confirmed from FIG. 5 , the electrostatic spinning is optimized, under the condition that a flow rate of the spinning solution is also decreased, as the molecular weight becomes larger.
[0064] The graph of FIG. 5 indicates that according to the molecular weight, a critical voltage (left vertical axis) and a flow rate (right vertical axis) are varied. The optimum voltage and the flow rate of electrostatic spinning may be determined according to variation in the molecular weight of the PAA polymers.
[0065] As may be seen from FIG. 5 , under the condition that an amount of the PAA contained in the spinning solution is set at 20 wt %, when the catalyst is used in an amount of 1 wt %, the PAA molecular weight, the voltage and the flow rate are determined at about 1.25 g/mol, 20.5 kV and 0.2 mL/H, respectively, to thereby obtain optimum spinning conditions.
[0066] Consequently, with the method of manufacturing the carbon nanofiber electrode according to the preferred embodiment of the present invention, the diameter of the PAA fibers may be adjusted to about 100 nm by controlling the electrostatic spinning conditions (e.g., a molecular weight and content (%) of the PAA polymers, a voltage and a flow rate) that affect the diameter of the carbon fibers.
[0067] After the PAA nanofiber papers are obtained by electrostatic spinning as mentioned above, the PAA nanofiber papers are converted into polyimide through a series of heating steps in air, to obtain polyimide (PI) nanofiber papers (S 40 ).
[0068] The series of heating is carried out by heating the PAA nanofiber papers at 100° C. for 2 hours, at 250° C. for 2 hours, and at 350° C. for 2 hours. At this time, the heating rate is 5° C./min. After imidization through the heating process, the mean diameter of the nanofibers is decreased by about 5 to 15%, as is shown in FIG. 5 .
[0069] Then, the polyimide (PI) nanofiber papers are carbonized by heating (S 50 ).
[0070] More specifically, the PI nanofiber papers are carbonized at 1,000° C. under an Ar atmosphere to convert the PI nanofiber papers into carbon nanofiber (CNF) papers.
[0071] The carbonization of PI nanofiber papers is sequentially carried out by elevating the temperature from ambient temperature to 600° C. over about one hour, and from 600° C. to 1000° C. over about 1.3 hour and then by maintaining at 1,000° C. over one hour.
[0072] Before the carbonization, the thickness of PI nanofiber papers was 397 μm. After the carbonization, the thickness of PI nanofiber papers is slightly decreased to 379 μm. As shown in FIG. 4 , the diameter of carbon nanofibers is slightly decreased by about 10 to 18%, as compared to that of polyimide nanofibers.
[0073] Accordingly, when the content of the PAA polymers in the spinning solution is adjusted to 18 wt % and the electrostatic spinning conditions are satisfied, carbon nanofibers with a mean diameter of about 90 nm may be prepared and a specific surface area of carbon nanofiber electrodes may thus be increased.
[0074] FIG. 6 is a graph showing correlation between a diameter of carbon nanofibers according to the preferred embodiment of the present invention, an electrical conductivity and a pressure.
[0075] The electrical conductivity of the carbon nanofiber papers obtained in the present embodiment varies depending upon the diameter of the carbon nanofibers. As the diameter of the carbon nanofibers becomes smaller, the electrical conductivity increases. As shown in FIG. 5 , the electrical conductivity is increased by pressurizing the carbon nanofiber papers during the carbonization.
[0076] That is, in the case where the diameter of the carbon nanofibers is 100 nm, when a pressure of 4400 Pa is applied to the carbon nanofibers, the electrical conductivity thereof is about 9 S/cm, and when a pressure of 22,000 Pa is applied thereto, the electrical conductivity thereof is about 16 S/cm.
[0077] Accordingly, in the process of manufacturing the carbon nanofiber electrode according to the preferred embodiment of the present invention, the carbonization is performed together with pressurization, to improve the electrical conductivity of the carbon nanofiber electrode.
[0078] Then, the carbon fiber papers thus carbonized are activated by surface-treatment in order to increase the surface area of the carbonized carbon fiber papers for use in a CDI electrode, to produce a carbon fiber electrode (S 60 ).
[0079] The activation of the carbon fiber papers is carried out by primarily heating the carbon fibers and KOH in a ratio of 1:2 to 1:4 at 400° C. and then by activating the resulting materials at 700 to 1,000° C. under a nitrogen atmosphere. The primary heating time and the activation time are each in the range of 1 to 2 hours.
[0080] Then, in order to introduce mesopores having a size of about 2 to 50 nm into the carbon fiber papers, the carbon fiber electrode is repeatedly (i.e., about 5 to 10 times) subjected to treatment with 1 M nitric acid and heat-treatment at 400° C., to form a carbon fiber electrode for a CDI apparatus (S 70 ). At this time, the nitric acid treatment time and the heating time are about 20 minutes and about 30 minutes, respectively.
[0081] As mentioned above, when the carbon fiber electrode prepared in accordance with the method of the present invention is applied to a CDI apparatus, the ion collection capability of the CDI apparatus can be improved by introducing mesopores into the carbon fiber papers.
[0082] FIG. 7( a ) is an electron microscope image of PAA nanofibers prepared in accordance with the preferred embodiment of the present invention. FIG. 7( b ) is an electron microscope image of PI nanofibers prepared in accordance with the preferred embodiment of the present invention. FIG. 7( c ) is an electron microscope image of CNT (carbon nanotube) nanofibers prepared in accordance with the preferred embodiment of the present invention. As is apparent from FIGS. 7( a )- 7 ( c ), the PAA nanofibers, PI nanofibers and carbon nanotube nanofibers prepared in accordance with the preferred embodiment of the present invention are decreased in size.
[0083] Hereinafter, a method to manufacture a carbon nanotube composite electrode according to the preferred embodiment of the present invention will be illustrated.
[0084] FIG. 8 is a flow chart illustrating a method to manufacture the carbon nanotube composite electrode according to the preferred embodiment of the present invention.
[0085] The manufacturing of the CNT/PAA composite according to the preferred embodiment of the present invention is carried out in the same manner as in the manufacturing of the carbon nanofiber electrode, except that the synthesis of PAA and the introduction of carbon nanotubes (CNTs) are used.
[0086] The carbon nanotubes used herein may have a diameter of about 0.4 nm to about 200 nm. Depending upon the number of the walls of carbon nanotubes, single-walled carbon nanotubes (SWCNTs) or multi-walled carbon nanotubes (MWCNTs) may be used.
[0087] The CNTs are homogeneously dispersed in DMF using a method such as ultrasonic wave treatment or stirring, and an ODA /DMF solution is added thereto. Then, PMDA and a TEA catalyst are added to the resulting mixture and then the mixture is subjected to polymerization.
[0088] At this time, the weight of CNTs in the CNT/PAA composite is preferably in the range of 0.001% to 50%. The CNT/PAA composite in which a percolation threshold of the CNTs is observed near 0.001% and the CNT content is 50% may be used.
[0089] Then, the resulting polymers are subjected to electrostatic spinning to prepare PAA/CNT fibers. The PA/CNT fibers are imidized to prepare a PI/CNT composite. Then, the PAA/CNT composite is heated for carbonization and activated to manufacture a CNF/CNT composite electrode.
[0090] Then, the resulting CNF/CNT composite electrode is subjected to acid treatment and heat treatment to obtain the final CNF/CNT composite electrode for a CDI apparatus, capable of improving the efficiency of the CDI apparatus.
[0091] This manufacturing process is carried out under the same conditions as in the manufacturing process of the carbon fiber electrode according to the preferred embodiment of the present invention. Thus, a more detail thereof will be omitted.
[0092] Hereinafter, a CDI apparatus using the carbon fiber electrode and/or carbon nanotube composite electrode manufactured prepared in accordance with the afore-mentioned method will be illustrated.
[0093] The technology called capacitive deionization (CDI) is based on a simple principle that when a voltage is applied across two electrodes of a positive electrode and a negative electrode, negative ions are electrically adsorbed on the positive electrode and positive ions are electrically adsorbed on the negative electrode to remove the ions dissolved in a fluid such as water. In accordance with the CDI, when the ions are saturatedly adsorbed on the electrode, they can be readily desorbed by reversing the polarity of the electrode, thus making it simple to recycle the electrode.
[0094] Unlike other methods such as an ion exchange resin method and reverse osmosis, the CDI does not employ a cleaning solution, e.g., an acid or a base, for the purpose of recycling the electrode, thus advantageously being free of the secondary-production of chemical wastes. The CDI has great advantages of a semi-permanent lifespan due to almost freedom from corrosion or contamination and a 10- to 20-fold energy savings due to high energy efficiency, as compared to other methods.
[0095] FIG. 9 is a schematic diagram illustrating a CDI apparatus comprising a carbon nanofiber electrode or a carbon nanotube composite electrode prepared according to the present invention.
[0096] To apply the CNF porous carbon electrodes (or CNF/CNT porous carbon electrodes) 50 a and 50 b thus manufactured to a CDI apparatus, the electrodes 50 a and 50 b are made to a size of 10 cm×10 cm, and a CID system consisting of 20 cells is then obtained. The electrodes are designed to be spaced apart from each other at a distance of 1 mm using a spacer (not shown). Graphite is used as a collector.
[0097] When a voltage of 0 to 1.2 V is applied to the positive electrode, negative ions are adsorbed on the positive carbon electrode 50 a and positive ions are adsorbed on the negative carbon electrode 50 b . At this time, when hard water of 1,000 ppm is treated at a flow rate of 100 ml/min, an ion removal ratio and an ion recovery ratio are 90% and 70%, respectively.
[0098] The carbon nanofiber electrode and carbon nanotube composite electrode according to the method of the present invention may be used in the field of water treatment including sea water desalination facilities, water purifying plants, wastewater utilities, semiconductor wastewater treatment utilities, water purifiers, water conditioners, washing machines, dishwashers, air conditioners (water suppliers of water-quenching heat-exchangers), steam cleaners, boiler scale control facilities, etc. Furthermore, the carbon nanofiber electrode and the carbon nanotube composite electrode may be used not only in all treatment facilities and products that employ the principle of adsorbing/desorbing ions dissolved in water by electricity, but also in the field of supercapacitors.
[0099] As is apparent from the foregoing, the method according to the present invention, the carbon nanofiber electrode and/or a carbon nanotube composite electrode are manufactured using triethylamine (TEA) as a catalyst to synthesize polyamic acid (PAA) as a polyimide (PI) precursor. As a result, diameters of carbon fibers may be minimized, and a specific surface area of the carbon fiber electrode may be thus increased.
[0100] In the process of manufacturing the carbon nanofiber electrode and/or carbon nanotube composite electrode, the carbonization is performed together with pressurization. Accordingly, it is possible to improve electrical conductivity of the electrodes.
[0101] The CDI apparatus according to the present invention uses the carbon nanofiber electrode and/or the carbon nanotube composite electrode manufactured by the method, thus advantageously exhibiting an improved ion collection capability.
[0102] Although a few embodiments of the present invention have been shown and described, it would be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents. | A method to manufacture a carbon fiber electrode comprises synthesizing polyamic acid (PAA) as a polyimide (PI) precursor from pryomellitic dian hydride (PMDA) and oxydianiline (ODA) as monomers and triethylamine (TEA) as a catalyst, adding dimethylformamide (DMF) to the polyamic acid (PAA) solution to prepare a spinning solution and subjecting the spinning solution to electrostatic spinning at a high voltage to obtain a PAA nanofiber paper, converting the PAA nanofiber paper into a polyimide (PI) nanofiber paper by heating, and converting the polyimide (PI) nanofiber paper into a carbon nanofiber (CNF) paper by heating under an Ar atmosphere. Also, the method to manufacture a polyimide carbon nanofiber electrode and/or a carbon nanotube composite electrode may utilize carbon nanofibers having diameters that are lessened by optimizing electrostatic spinning in order to improve spinnability. | 3 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Divisional Application of U.S. patent application Ser. No. 10/073,133, filed Feb. 13, 2002, which claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional Application No. 60/270,620, filed Feb. 23, 2001.
FIELD OF THE INVENTION
[0002] The present invention relates generally to surgical devices, and more particularly, to devices for reapproximating two or more parts of a patient's sternum.
BACKGROUND OF THE INVENTION
[0003] Many surgical procedures require two or more parts of a sternum to be reapproximated, or fixed together, such as sternal reconstruction and repair of sternal trauma. In addition, various types of surgical procedures are currently performed to investigate, diagnose, and treat diseases involving tissues or organs located in a patient's thoracic cavity, such as the heart and lungs. These procedures typically require a partial or median sternotomy to gain access to the patient's thoracic cavity. A partial or median sternotomy is a procedure by which a saw or other appropriate cutting instrument is used to make a midline, longitudinal incision along a portion or the entire axial length of the patient's sternum, allowing two opposing sternal halves to be separated laterally. A large opening into the thoracic cavity is thus created, through which a surgeon may directly visualize and operate upon the heart and other thoracic organs, vessels, or tissues. Following the surgical procedure within the thoracic cavity, the two severed sternal halves must be reapproximated.
[0004] Sternum fixation has traditionally has been performed using stainless steel wires that are wrapped around or through the sternal halves and then twisted together, so as to compress the two halves together. Other methods of sternum fixation include the use of band or strap assemblies. Such assemblies typically include a locking mechanism, which secures a strap in a closed looped configuration around the sternum halves. While utilization of steel wires and strap assemblies have been widely accepted for sternum fixation, these devices present a number of disadvantages. For example, steel wires are susceptible to breakage, are difficult to maneuver and place around the sternum, and often have sharp ends that can pierce through the surgeon's gloves or fingers. Steel wire and band assemblies also provide insufficient or non-uniform clamping force on the sternal halves, thus resulting in sternal nonunion. The steel wire and band assemblies also provide insufficient clamping forces in all three planar directions, thus leading to healing problems caused by unwanted bone movements leading to raking and rubbing of the surrounding tissue or bone.
[0005] Several other techniques of sternal fixation have been developed for reapproximating the sternal halves. One technique uses plates that are located on both sternal halves across the sternotomy and are fixed thereto by means of screws through the bone on either side of the sternotomy. This technique, however, is not optimal because it requires direct fixation of the plates to the bone with screws, making reentry into the thoracic cavity through the sternotomy extremely difficult in case of a medical emergency.
[0006] Another technique uses a sternal clamp having a pair of opposed generally J-shaped clamp members which are laterally adjustable relative to one another but can be rigidly joined with a set of machine screws. Similar to the use of plates, discussed above, this technique does not provide quick access to the organs and/or tissues within the patient's thoracic cavity.
[0007] Yet another fixation device comprises a pair of hook-shaped clamps that slide together and lock in position with respect to one another using a ratchet assembly. The ratchet assembly provides quickened accesses to the thoracic cavity, but is cumbersome to use and is limited to the hook-shaped clamp members disclosed.
[0008] Therefore, it is desirable to provide a sternum fixation device that stabilizes the sternum in all three planar directions, has a fast and easy to use quick-release feature, and works in several different configurations.
SUMMARY OF THE INVENTION
[0009] The present invention is directed to a sternum fixation device for securing parts of a sternum. The sternum fixation device includes a first plate and a second plate. The first plate has an upper surface and a sternum-contacting surface, at least one hole passing through the upper and sternum-contacting surfaces for receiving a fastener head of a bone fastener, and a first longitudinal bore defining an axis oriented substantially transversely to the at least one hole. The at least one hole may be threaded to receive a threaded fastener head. The second plate has an upper surface and a sternum-contacting surface, an attachment member for fixation to the sternum, and a second longitudinal bore. The first and second plates are dimensioned to mate with one another such that the first and second longitudinal bores are aligned to receive the release member, and removal of the release member from the first and second longitudinal bores allows separation of the two parts of the sternum. The first and second plates mate with one another such that they cannot rotate with respect to one another about the release member.
[0010] According to one aspect of the present invention, the release member is a pin, which may be a single pronged pin. The pin may have a splayed apart tip portion. Alternatively, the release member is a two pronged pin, which may be angled with respect to a mating line between the first and second plates. The release member may also be a cam or quarter-turn fastener, and the first and second plates may be provided with matching sets of ratchet teeth that cooperate with the release member to allow the distance between the first and second plates to be varied.
[0011] The attachment member may be a threaded through hole that passes through the second plate upper and sternum-contacting surfaces for receiving a threaded fastener head. To increase pull-out resistance of the fastener, the at least one threaded hole may be angled away from the second plate.
[0012] According to another embodiment of the present invention, the attachment member is a hook member for engaging an intercostal space portion of the sternum. Preferably, the attachment member comprises at least two hook members that are spaced apart by an adjustable lateral distance. Alternate embodiments include multiple combinations of fastener and hook-shaped attachment members.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a perspective view of a first embodiment of a sternum fixation device according to the present invention;
[0014] FIG. 2 is an exploded perspective view of the sternum fixation device of FIG. 1 ;
[0015] FIG. 3 is a perspective view of the sternum fixation device of FIG. 1 , having a U-shaped release member;
[0016] FIG. 4 is an exploded perspective view of the sternum fixation device of FIG. 3 ;
[0017] FIG. 5 is a perspective view of the sternum fixation device of FIG. 1 , having differently shaped first and second mating portions;
[0018] FIGS. 6-7 are exploded perspective views of the sternum fixation device of FIG. 5 , showing variations of the first and second mating portions and release member;
[0019] FIG. 8 is an elevational view of the sternum fixation device of FIG. 5 , wherein the release member is angled with respect to a mating line between the first and second plates;
[0020] FIG. 9 is a perspective view of the sternum fixation device of FIG. 1 , having differently shaped first and second mating portions;
[0021] FIGS. 10-12 are elevational views of the sternum fixation device of FIG. 5 , having additional first and second attachment members;
[0022] FIG. 13 is a perspective view of the sternum fixation device of FIG. 5 , having additional first and second attachment members;
[0023] FIG. 14 is a perspective view of a sternum fixation device of FIG. 1 , having an alternate embodiment of the release member of FIG. 1 ;
[0024] FIG. 15 is a perspective view of a second embodiment of a sternum fixation device according to the present invention, having hook-shaped attachment members;
[0025] FIG. 16 is a perspective view of the sternum fixation device of FIG. 15 , having adjustably spaced-apart hook members;
[0026] FIG. 17 is a perspective view of the sternum fixation device of FIG. 15 , having first and second attachment members including a combination of hooks and threaded fastener holes;
[0027] FIG. 18 is a perspective view of the sternum fixation device of FIG. 15 , having an alternate embodiment of the release member; and
[0028] FIG. 19 is an elevational view of a bone fastener having a threaded head portion for use with one embodiment of the first and second attachment members according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0029] FIGS. 1 and 2 show a first illustrative embodiment of a sternum fixation device according to the present invention, shown as sternum fixation device 10 . Sternum fixation device 10 includes first and second mating plates 12 , 14 attached to one another by a release member 16 . First plate 12 and second plate 14 may be used to reapproximate, or secure together, two or more parts of a sternum by attaching each plate to a part of the sternum. Sternum fixation device 10 may be constructed from any suitable bio-compatible material including, but not limited to, bioresorbable materials, radio-translucent materials, allograft materials, stainless steel and titanium
[0030] First plate 12 includes an upper surface 18 and a sternum-contacting surface 20 , and a first attachment member 22 for attachment to the sternum. First attachment member 22 is shown as a plurality of threaded holes that are configured to receive a threaded head portion 44 of a fastener, such as a bone screw 42 , shown in FIG. 19 . The fastener may alternatively have an elongated shaft with barbs formed thereon that anchor the fastener in the bone. Second plate 14 includes an upper surface 24 and a sternum-contacting surface 26 , and a second attachment member 28 , also shown as a plurality of threaded holes for receiving a threaded head portion of a bone screw 42 . Alternatively, the holes of the first and second attachment members 22 , 28 may not have threads and receive a non-threaded head portion of a fastener. Sternum-contacting surfaces 20 , 26 may be scalloped, or provided with various other surface treatments that are known by one of ordinary skill in the bone plating art to minimize the contact area between the first and second plates 12 , 14 and the respective parts of the sternum.
[0031] First plate 12 further includes a series of first joining portions 30 that inter-digitate with corresponding second joining portions 32 on second plate 14 . A first longitudinal bore 34 extends through the first joining portions 30 and a second longitudinal bore 36 extends through the second joining portions 32 such that when first plate 12 and second plate 14 are positioned adjacent one another with the first and second joining portions 30 , 32 inter-digitated, the first and second longitudinal bores 34 , 36 are substantially aligned and may receive release member 16 . Alternatively, the first and second joining portions 30 , 32 could be provided with multiple sets of aligned longitudinal bores to allow the distance between the first and second attachment members 22 , 28 to be varied to accommodate a range of sternum sizes.
[0032] As shown in FIGS. 1 and 2 , release member 16 is shown as an elongated pin having a curved grip portion 35 . Release member 16 could alternatively have a T-shaped grip portion. When inserted into aligned first and second longitudinal bores 34 , 36 , release member 16 secures the first and second plates 12 , 14 together. As shown in FIG. 2 , when the release member 16 is removed from the first and second longitudinal bores 34 , 36 , the first and second plates 12 , 14 are allowed to separate. Thus, release member 16 can be removed from the first and second longitudinal bores 34 , 36 to quickly and conveniently gain access to the thoracic cavity. This quick release mechanism can be useful, for example, in the case of a medical emergency.
[0033] According to one aspect of the present invention, first and second joining portions 30 , 32 may be configured such that the first and second plates 12 , 14 cannot rotate with respect to one another about the release member 16 , thus providing increased stabilization of the two parts of the sternum. As shown in FIG. 2 , the first and second joining portions 30 , 32 overlap as well as inter-digitate, thus fixing the plates together such that they do not rotate with respect to one another. As an alternative to overlapping the joining portions, release member 16 may be configured to prevent relative rotation between the first and second plates 12 , 14 . For example, release member 16 and the first and second longitudinal bores 34 , 36 may have matching polygonal cross-sections, such as rectangular, square, or triangular, which prevent rotation of either of the plates 12 , 14 relative to the release member 16 and consequently, relative to one another. The matching cross-sections may also be ovular. Alternatively, release member 16 may be a multi-pronged pin and the first and second joining portions 30 , 32 may be provided with multiple sets of aligned longitudinal bores. One of ordinary skill in the bone plating art, however, will know and appreciate than any number of configurations may be used to prevent rotation between the first and second plates 12 , 14 .
[0034] Referring to FIGS. 3 and 4 , a variation of sternum fixation device 10 is shown with release member 16 in the form of a U-shaped pin having spaced apart leg portions 37 , 39 . The first and second plates 12 , 14 have first and second joining portions 30 , 32 that are spaced apart such that a central opening 33 is defined between the first and second plates 12 , 14 . Central opening 33 serves to minimize the amount of implanted material that contacts the sternum. A third longitudinal bore 38 extends through the first mating portion 30 and a fourth longitudinal bore 40 extends through the second mating portion 32 . The third and forth longitudinal bores 38 , 40 are located such that when the first plate 12 and second plate 14 are positioned adjacent one another with the first and second joining portions 30 , 32 inter-digitated, the first and second longitudinal bores 34 , 36 are substantially aligned, as are the third and forth longitudinal bores 38 , 40 . Thus, each of the release member leg portions 37 , 39 may be received in one of the aligned pairs of bores to secure the first and second plates 12 , 14 together. The spaced apart relationship of leg portions 37 , 39 and the respective sets of aligned longitudinal bores prevents the first and second plates 12 , 14 from rotating with respect to one another about the release member 16 , thus stabilizing the sternum fixation device 10 .
[0035] Still referring to FIGS. 3 and 4 , the first and second attachment members 22 , 28 are in the form of a plurality of threaded holes configured to receive a threaded head 44 of a bone screw 42 . To reduce the tendency of the bone screws 42 to pull out of the sternum, the threaded holes of the first attachment member 22 and the second attachment member 28 may be angled such that the threaded tip portions 46 of opposing bone screws, for example, bone screws 42 a and 42 b, are angled towards one another.
[0036] FIGS. 5-12 show several additional variations of sternum fixation device 10 . In each of the variations shown, first and second plates 12 , 14 are reduced in size so that they outline the first and second attachment members 22 , 28 , thereby reducing the amount of material that contacts the sternum. Referring to FIGS. 5, 6 and 7 , the first and second joining portions 30 , 32 may each have protrusions and/or indentations formed thereon to prevent them from rotating with respect to one another. As shown in FIG. 6 , second joining portion 32 includes transverse tabs 48 and groove 50 , and first joining portion 30 has mating grooves 52 and tab 54 formed thereon, which cooperate to prevent rotation between the first and second plates 12 , 14 . Release member 16 has a resiliently expanded, or splayed, tip portion 56 that provides resistance against the release member 16 coming out of first and second longitudinal bores 34 , 36 . Release member 16 may alternatively be a taper pin. As shown in FIG. 7 , tabs 48 and grooves 52 may be oriented parallel to the joining portions, however, one of ordinary skill in the bone plating art will know and appreciate that any number of configurations of mating protrusions and/or indentations may be formed on the first and second mating portions 30 , 32 to prevent rotation between them.
[0037] FIG. 8 shows a variation of sternum fixation device 10 wherein the first and second longitudinal bores 34 , 36 are oriented at an angle 58 to the intersection 57 of first and second plates 12 , 14 . When release member 16 is received in aligned first and second longitudinal bores 34 , 36 (hidden in FIG. 8 ), the skewed orientation of release member 16 with respect to intersection 57 prevents rotation between the first and second plates 12 , 14 . FIG. 9 shows another variation of sternum fixation device 10 having a release member 16 in the form of a U-shaped pin, as discussed above with respect to FIGS. 3 and 4 . Release member 16 could alternatively be a V-shaped pin, a T-shaped pin, or any other shape known to one of ordinary skill in the art. FIG. 10 shows a variation of sternum fixation device 10 having first and second attachment members 22 , 28 comprising three threaded fastener or screw holes each, and a skewed release member 16 . FIG. 11 shows another variation having a U-shaped release member 16 with an enlarged ring-shaped grip portion 35 . FIG. 12 shows yet another variation where first attachment member 22 and second attachment member 28 each comprise six threaded fastener or screw holes for receiving a threaded head 44 of a bone fastener or bone screw 42 . FIG. 13 shown a variation where the first attachment member 22 and the second attachment member 28 are arranged in a H-shaped pattern. One of ordinary skill in the bone plating art will know and appreciate that any of the features and variations described above may be combined to produce a sternum fixation device according to the present invention.
[0038] FIG. 14 , shows an alternate embodiment of a release member 116 according to the present invention, which comprises a pair of quarter-turn fasteners or screws, or other cam-type screws known by one of ordinary skill in the art. The first joining portions 130 each have a countersunk bore 134 for receiving a head 135 of the release member 116 , and the second joining portions 132 each have a threaded bore, or cam surface 136 (hidden in FIG. 14 ), for receiving a threaded or cam portion 137 (hidden in FIG. 14 ) of the release member 116 , or vice versa. The first joining portions 130 overlap the second joining portions 132 , or vice versa, such that the release member 116 can be inserted through the countersunk bore 134 and be received by cam surface 136 to secure the first and second plates 12 , 14 together. To separate the first and second plates 12 , 14 the release member 116 is rotated through a predetermined angle preferably of less than 360 degrees, such as, for example ninety degrees, to release the cam portion 137 of the release member 116 from the cam surface 136 and allow the first and second plates 12 , 14 to come apart.
[0039] Referring to FIGS. 14-17 , a second embodiment of the present invention is shown as sternum fixation device 210 . Sternum fixation device 210 includes first and second plates 212 , 214 attached to one another by release member 216 . First plate 212 includes an upper surface 218 and a sternum-contacting surface 220 , and first attachment member 222 . As will be discussed in more detail below, first attachment member 222 is a plurality of hooks that are configured and dimensioned to engage the sternum between the intercostal spaces. Second plate 214 includes an upper surface 224 and a sternum-contacting surface 226 , and second attachment member 228 . Second attachment member 228 is a plurality of holes for receiving a bone fastener or screw 242 , which holes are preferably threaded to receive a threaded head 244 of the bone screw 242 .
[0040] First plate 212 further includes a first joining portion 230 that overlaps with corresponding second joining portion 232 on second plate 214 . An elongated slot 234 extends through the second joining portion 232 and is dimensioned to receive release member 216 , which is a cam, as shown in FIGS. 14 and 15 , or quarter-turn fastener or screw, as shown in FIG. 16 . As shown in FIGS. 14 and 15 , release member 216 may be a generally rectangular cam that is rotatable between a locking position and a releasing position and has a first dimension 260 that can pass through the slot 234 when it is oriented parallel thereto, but can not pass through the slot 234 when it is substantially transverse thereto. Thus, when release member 216 is in the locking position, the first dimension 260 is oriented substantially transverse to the elongated slot 234 and locks the first and second plates 212 , 214 together. When release member 216 is rotated into the releasing position, the first dimension 260 is in alignment with the elongated slot 234 and allows separation of the first and second plates. FIG. 16 shows release member 216 as a quarter-turn screw having a head 235 and a threaded portion 237 (hidden). Threaded portion 237 passes through elongated slot 234 and engages a threaded bore 236 (hidden) in first joining portion 230 , and head 235 engages the upper surface 224 of second joining portion 232 to lock the first and second plates 212 , 214 together. According to either configuration of release member 216 , cam or quarter-turn screw, the first and second plates 212 , 214 may be separated by rotating release member 216 through a predetermined angle preferably of less than 360 degrees, such as, for example, ninety degrees, to free release member 216 from elongated slot 234 and allow the first and second plates 212 , 214 to separate. One of ordinary skill in the art will know and appreciate that any number of cam or quarter-turn screw configurations may be used to releasably lock the first and second plates 212 , 214 together.
[0041] Referring to FIGS. 14-16 , first and second joining portions 230 , 232 may each have a series of transverse ratchet teeth 262 , 264 defined thereon that cooperate to lock first and second plates 212 , 214 together. The position of second joining portion 232 may be varied incrementally with respect to first joining portion 232 , provided that release member 216 is maintained within the boundaries of elongated slot 234 , which position may be locked by the cooperation of transverse ratchet teeth 262 , 264 , which are pressed together by release member 216 . Thus, first and second plates 212 , 214 can be locked together at varying distances apart from one another, allowing sternum fixation device 210 to be used with sternums of different sizes.
[0042] FIG. 18 shows a variation of sternum fixation device 210 where release member 216 is a U-shaped pin that is received in sets of substantially aligned longitudinal bores 234 (hidden), 236 and 238 (hidden), 240 disposed in inter-digitated first and second joining portions 230 , 232 , as described above with respect to sternum fixation device 10 . One of ordinary skill in the art will appreciate that all the configurations of the release member 16 and the first and second joining portions 30 , 32 , as described above with respect to sternum fixation device 10 , may also be used with sternum fixation device 210 .
[0043] Referring back to FIG. 15 , first attachment member 222 is shown as a pair of laterally spaced-apart, generally curved hooks for engaging the intercostal spaces of a patient's sternum. First attachment member 222 may have C-shaped, J-shaped, L-shaped, or any other shaped hooks known in the art to be suitable for engaging the intercostal spaces of a sternum. One of ordinary skill in the art will appreciate that first attachment member 222 may have any number of hooks configured for engaging any respective number of intercostal spaces. In addition, first attachment member 222 can be made having various different dimensions, such as the size of the hooks and the lateral spacing therebetween, to accommodate sternums having different sizes and proportions. FIG. 16 shows a variation of first attachment member 222 where the number of hooks 270 and the lateral distance between them is adjustable. First plate 212 has a longitudinal array of mounting apertures 272 defined therein for receiving mounting bolts 274 that secure the hooks to the first plate 212 , thus allowing the mounting position of the hooks to be adapted to conform to varying distances between intercostal spaces. Mounting bolts 274 are preferably recessed into mounting apertures 272 , for example, by countersinking or counterboring the apertures 272 , to reduce the amount of material protruding above upper surface 218 . Referring to FIGS. 17 and 18 , the first attachment member 222 can have pointed, self-dissecting tip portions 276 that aid in inserting the hooks through soft tissue and muscle that is found in the intercostal spaces. First attachment member 222 can additionally have apertures 278 (shown in FIG. 17 ) defined therein for receiving pins that may be used to stabilize attachment member 222 in the intercostal space.
[0044] While it is apparent that the illustrative embodiments of the invention herein disclosed fulfill the objectives stated above, it will be appreciated that numerous modifications and other embodiments may be devised by those skilled in the art. For example, as shown in FIG. 17 , sternum fixation device 210 may further include third attachment member 280 , a threaded hole for receiving a threaded head portion 244 of a bone fastener or screw 242 , and fourth attachment member 282 , an intercostal space hook. One of ordinary skill in the art will appreciate that sternum fixation device 210 may include any number and combination of attachment members, such as hooks and bone screws, and release members, such as pins, U-shaped pins, and cam members. Therefore, it will be understood that the appended claims are intended to cover all such modifications and embodiments which come within the spirit and scope of the present invention. | A sternum fixation device for securing parts of a sternum includes first and second removably associated plates. The first plate has an upper surface and a sternum-contacting surface, and at least one hole passing through both of these surfaces for receiving a fastener head. The second plate has at least one attachment member for fixation to the sternum. A release member holds the first and second plates together, and is movably associated with at least one of the first and second plates such that it may be moved to allow separation of the two parts of the sternum. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2002-159988, filed May 31, 2002, the entire contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates generally to an information processing apparatus including a pointer indicator function, and more particularly to an information processing apparatus having a plurality of display screens for displaying operation screens and a method for providing notification when an operation screen is changed.
[0004] 2. Description of the Related Art
[0005] In recent years, various portable personal computers of a notebook or laptop type have been developed. This type of portable personal computer includes various functions for enhancing operability.
[0006] One example of such a function is a pointing device for a portable computer. An example of this type of pointing device is a tablet device which includes a touch pad as described in Jpn. Pat. Appln. KOKAI Publication No. 8-44493 and which has been broadly used. When pointing operations such as a touch movement operation and tap operation are performed on this tablet device, various screen operations are possible such as controlling movement of a mouse pointer displayed on a display device and selection of a display button.
[0007] Moreover, in recent years, this type of portable personal computer includes various functions for enhancing the operability. One such function is a two-screen cooperation function of displaying a plurality of operation screens at the same time and reflecting the operation of one of the operation screens in another operation screen so that two-screen parallel operation is possible.
[0008] In the above-described prior-art document, a technique is described comprising: performing a touch operation in a position corresponding to an input field in a displayed application screen on a display screen to which a touch panel is attached to display a software keypad in one corner on the display screen. With this two-screen cooperation function, an input operation can be facilitated and accelerated.
[0009] Furthermore, the computer system described in the above-described prior-art document is constituted such that two screens to be operated in conjunction with each other are displayed on a single display (device). However, to further enhance operation, a system constitution has been realized in which one device includes two displays (devices). One display is used for main operation (main display), and the other display is used for sub-operation (sub-display).
[0010] However, there are problems which prevent the effective use of this two display system. One of the problems is that the user looks at the main display while performing a touch operation on the sub-display and the user is therefore apt to neglect visual screen operation confirmation of the sub-display.
[0011] As a result, when the operation screen of the sub-display changes as a result of an erroneous operation by the user on the operation screen of the sub-display without the user immediately being aware of it, problems may result. For example, an operation which has been performed may become invalid, or further erroneous operations may be performed before the first erroneous operation is detected.
[0012] In order for a user to avoid such negative results, the user must frequently visually check the display screen of the sub-display to ensure that such an erroneous operation has not occurred. However, for users skilled in “touch operation” (i.e., sightless or “blind” operation) of the sub-display, frequent visual checks of the sub-display may decrease the user's efficiency and may be annoying to the user, because such a user may prefer to instead focus on the main display screen substantially all through the operation.
[0013] Because such users skilled in touch operation do not frequently check the sub-display, however, a lot of time may pass before an erroneous operation is noticed by the user, possibly resulting in further erroneous operations. Furthermore, if a user has to constantly be switching his visual focus between the main display and the sub-display, the operability of the information processing apparatus may be impaired.
[0014] As described above, in the related art, in processing devices such as a portable computer, the main display and sub-display are provided, and an operable screen is displayed on each display. In this case, during the performing of the touch operation on the main display, the operator looks at the main display. Therefore, the operator is apt to neglect the screen operation confirmation of the sub-display, and there are problems that erroneous operation is caused and that operability is impaired.
SUMMARY OF THE DISCLOSURE
[0015] According to embodiments of the present invention, an information processing apparatus and method is disclosed. The apparatus and method provides a main display for displaying a first operation screen used to perform a first operation and a sub-display separate from the main display for displaying a second operation screen used to perform a second operation.
[0016] According to one embodiment, the sub-display is integral with a touch pad pointing device. A processor of the information processing apparatus is programmed to provide notification when the second operation screen is opened or changed.
[0017] According to further embodiments of the present invention, the notification may be selectively provided on the main display such that a user performing touch operation on the sub-display while viewing the main display is notified that the second operation screen has been opened or changed. The notification may be visual, audible or tactile.
[0018] According to still further embodiments of the present invention, the second operation may be executed in parallel with the first operation or independently of the first operation. The first operation screen and the second operation screen may be simultaneously displayed.
[0019] These and other features and advantages of embodiments of the invention will be apparent to those skilled in the art from the following detailed description of embodiments of the invention, when read with the drawings and appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] [0020]FIG. 1 is a diagram showing an appearance of a information processing apparatus according to an embodiment of the present invention;
[0021] [0021]FIG. 2 is a block diagram showing a constitution of the information processing apparatus, according to embodiments of the present invention;
[0022] [0022]FIG. 3 is a block diagram showing a main part of the system, according to embodiments of the present invention;
[0023] [0023]FIG. 4 is an explanatory view of an operation method on a main, according to embodiments of the present invention;
[0024] [0024]FIG. 5 is an enlarged view of a part of a screen of the main display, according to embodiments of the present invention;
[0025] [0025]FIG. 6 is a diagram showing one example of a changeover menu screen displayed on the main display, according to embodiments of the present invention;
[0026] [0026]FIG. 7 is a diagram showing one example of an operation screen displayed on the main display, according to embodiments of the present invention;
[0027] [0027]FIG. 8 are diagrams showing a temporary shape change of a mouse pointer displayed on the main display, according to embodiments of the present invention; and
[0028] FIGS. 9 to 12 are flowcharts showing a procedure of an operation process, according to embodiments of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0029] An embodiment of the present invention will be described hereinafter with reference to the drawings.
[0030] According to the present embodiment, a pointing device with an integral display is provided in an information processing device. In the information processing device, a display panel (sub-display) such as an LCD and a touch pad or tablet integral with the sub-display are provided separately from a display device (main display) in which a mouse pointer is displayed. The present embodiment is characterized in that various setting screens and operation screens are set and operated in this device.
[0031] One example of a display-equipped pointing device that is available is the cPad™ by Synaptics, Inc., 2381 Bering Dr., San Jose, Calif. 95131. (see http://www.synaptics.com/products/cPad.cfm). In the embodiment of the present invention, an example of a constitution will be described in which the cPad™ (hereinafter referred to as the cPad™ device) is used in the pointing device of the display united type.
[0032] [0032]FIG. 1 is a diagram showing an appearance of an information processing apparatus in the present embodiment. Here, an example of a notebook-size personal computer will be described.
[0033] As shown in FIG. 1, the computer according to the present embodiment is constituted of a computer main body 11 and display unit 12 . In the display unit 12 , a display screen (main display) 121 including an LCD is incorporated.
[0034] The display unit 12 is attached to the computer main body 11 so that the unit can rotate between a released position and closed position. The computer main body 11 includes a thin box-shaped housing, a keyboard 111 is disposed in a housing upper surface, and the upper surface of a housing portion in front of the keyboard 111 forms an arm rest. Substantially in a middle portion of the arm rest, a cPad™ device 112 which is used as the pointing device of the display united type as described above according to the present invention is disposed together with a left button 113 a, right button 113 b, and middle button 113 c included in the cPad™ device. Furthermore, in the upper surface of the computer main body 11 , a power button 114 is disposed to turn on/off a power supply of the computer main body 11 .
[0035] [0035]FIG. 2 is a block diagram showing a constitution of the computer system of the present embodiment.
[0036] As shown, this computer includes a CPU 201 , host bridge 202 , main memory 203 , graphics controller 204 , PCI-ISA bridge 206 , I/O controller 207 , hard disk drive (HDD) 208 , CD-ROM drive 209 , USB controller 210 , embedded controller/keyboard controller IC (EC/KBC) 211 , and power supply controller 213 .
[0037] A PCI bus 1 connected between the host bridge 202 and PCI-ISA bridge 206 is connected to various controllers such as the I/O controller 207 , USB controller 210 , and sound controller 106 .
[0038] The cPad™ device 112 and a USB port 228 are connected to the USB controller 210 . The cPad™ device 112 includes a touch pad 112 a, display portion 112 b, and backlight 112 c which are united, and also includes the left button 113 a, right button 113 b, and middle button 113 c. The sound controller 106 is connected to a sound output portion 107 such as a speaker and beeper.
[0039] The CPU 201 is disposed to control the operation of the present computer, and executes an operating system and application program/utility program loaded in the main memory 203 from the hard disk drive (HDD) 208 .
[0040] In the present embodiment, the application program related to the operation of the cPad™ device 112 is executed as shown in FIGS. 9 and 10. An execution process of the application program will be described later.
[0041] The host bridge 202 is a bridge device for bi-directionally connecting a local bus of the CPU 201 to the PCI bus 1 . The graphics controller 204 controls the main display 121 which is used as a display monitor of the present computer. Moreover, when an external display is connected to a connection port for the external display, the graphics controller 204 controls the external display.
[0042] The I/O controller 207 controls the hard disk drive (HDD) 208 , and CD-ROM drive 209 . The PCI-ISA bridge 206 is a bridge device for bi-directionally connecting the PCI bus 1 to an ISA bus 2 , and includes various system devices such as a system timer, DMA controller, and interrupt controller.
[0043] The embedded controller/keyboard controller IC (EC/KBC) 211 is a one-chip microcomputer in which an embedded controller (EC) for managing power and a keyboard controller (KBC) for controlling the keyboard 111 are integrated. This embedded controller/keyboard controller IC (EC/KBC) 211 has a function of cooperating with the power supply controller 213 to turn on/off power in response to the user's operation of the power button 114 .
[0044] [0044]FIG. 3 is a block diagram showing the main part of the system in the present embodiment. Here, constituting elements include: a setting table 301 for setting the function of the cPad™ device 112 ; a control program 302 for controlling the function of the cPad™ device 112 in accordance with the content of the setting table 301 ; an interface 303 for controlling input/output of information exchanged between the cPad™ device 112 and control program 302 ; a setting program 311 for preparing the setting table 301 by GUI; execution means 312 for executing various processes in accordance with the instruction of the control program 302 ; and the cPad™ device 112 .
[0045] [0045]FIG. 4 is a diagram showing one example of display on the main display 121 . There are displayed a tray icon (cPad™ property icon) 411 concerning the operation of the cPad™ device 112 , and a pull-down menu 412 opened when the cPad™ property icon 411 is clicked/operated.
[0046] [0046]FIG. 5 is a diagram showing the display of FIG. 4 in an enlarged size. That is, there are also displayed the cPad™ property icon 411 on the main display 121 , and the pull-down menu 412 opened when the cPad™ property icon 411 is selected/clicked/operated with a mouse pointer (MC).
[0047] In the pull-down menu 412 , enable cPad™ function items 415 are disposed to provide various functions such as, but not limited to, functions for setting a changeover operation screen and for setting the display and operation of the operation screen operated by the cPad™ device 112 to be valid/invalid. Using the enable cPad™ function items 415 , it is possible to display and operate a changeover operation screen (changeover menu screen) 431 operated by the cPad™ device 112 in the main display 121 , as shown in FIG. 6. It is also possible to display and operate an operation screen 432 changed (selected) in the changeover menu screen 431 in the main display 121 , for example as shown in FIG. 7. Moreover, this function can be set to be invalid.
[0048] [0048]FIG. 6 is a diagram showing an exemplary changeover menu screen 431 displayed on the main display 121 and operated by the cPad™ device 112 .
[0049] In the present embodiment, the changeover menu screen 431 to be operated by the cPad™ device 112 is displayed in the vicinity of a pointing region being operated on the main display 121 . In the changeover menu screen 431 , selection buttons (icons) Ia, Ib, . . . of various operation screens to be operated by the cPad™ device 112 , such as, but not limited to, numeric keys, calculator, memo, image drawing, and property are disposed.
[0050] [0050]FIG. 7 is a diagram showing one example of an operation screen 432 displayed on the main display 121 and operated by the cPad™ device 112 . For example, when the selection button Ib of the calculator is clicked on the changeover menu screen 431 shown in FIG. 6, an operation screen of a calculator is displayed, as shown in FIG. 7, and calculation is possible using the calculator on the operation screen.
[0051] [0051]FIG. 8 shows a temporary shape change of the mouse pointer displayed on the main display 121 . That is, the shape temporarily changes at the display start and changeover times of the screen operated by the cPad™ device 112 .
[0052] In the present embodiment, when the display of the screen (changeover menu screen 431 , operation screen 432 ) operated by the cPad™ device 112 is opened (started) or changed, the mouse pointer on the main display 121 temporarily changes from the mouse pointer (MC) having a first shape, for example, the shape shown on the left side of FIG. 8 to a mouse pointer (TD) having the second shape, for example, the shown on the right side of FIG. 8. Thereby, the user is notified of the start and changeover of the display of the screen operated by the cPad™ device 112 . For the purpose of notification, in the present embodiment, the shape of the mouse pointer is changed. However, the user may also be notified, for example, by changing the color of the mouse pointer, by a flashing display or by any other suitable visual method. In addition, the user may be notified tactilely by, for example, a vibration of some portion of the information processing apparatus. In the present embodiment, when any operation screen is not selected on the changeover menu screen 431 , the cPad™ device 112 is used as a pointing device equal to the mouse. Therefore, although the pointer on the main display 121 operated with the cPad™ device 112 may be referred to as a mouse pointer, operating as a mouse pointer is only one function of the pointer.
[0053] FIGS. 9 to 12 are flowcharts showing a procedure of an operation process of the present embodiment. FIG. 9 is a flowchart showing the procedure of the operation input process of the cPad™ device 112 , which is executed by the control program 302 to control the cPad™ device 112 . FIG. 10 is a flowchart showing the procedure of the operation process of the cPad™ device 112 , which is executed by the main CPU 201 . FIGS. 11 and 12 are flowcharts showing the procedure of the operation process in cPad™ screen processing.
[0054] An operation in the present embodiment will be described hereinafter with reference to FIGS. 9 to 12 .
[0055] Immediately after starting the system, an operation input mode is obtained in which the cPad™ device 112 reflects the pointing operation of the cPad™ device 112 in the mouse pointer displayed on the main display 121 . In this case, the cPad™ device 112 functions as a usual mouse pointing operation screen.
[0056] In this state, for example, the middle button 113 c disposed in the cPad™ device 112 is operated, and a selection operation (operation for changing the operation screen) of another function mode of the cPad™ device 112 is performed. Then, the changeover menu screen is displayed in the display portion 112 b of the cPad™ device 112 in the same manner as for the changeover menu screen 431 shown in FIG. 6. For example, when the selection button Ib of the calculator is clicked on the changeover menu screen 431 , the operation screen of the calculator is displayed in the same manner as in the operation screen 432 shown in FIG. 7, and the calculation using the calculator is possible on the operation screen.
[0057] In this case, an operation input command following the operation on the cPad™ device 112 is accepted on the control program 302 of the cPad™ device 112 (step S 11 ). At every acceptance, it is judged whether or not the operation input command is an operation input command for changing the operation screen (step S 12 ). When the operation input command is not the command for changing the operation screen, the processing is executed in accordance with the command (step S 14 ). On the other hand, with the operation input command to change the operation screen, an event indicating that the operation screen be changed is issued (step S 13 ). This event is notified to the main CPU 201 via the USB controller 210 . Therefore, when the main display 121 is visually checked and touch operation is performed, and even when the operation for changing the cPad™ operation screen is performed by mistake on the cPad™ device 112 , the above-described event is notified to the main CPU 201 .
[0058] On the other hand, when the cPad™ property icon 411 included in the tray icons is clicked/operated with the mouse pointer (MC) on the main display 121 as shown in FIGS. 4 and 5, the pull-down menu 412 is displayed. When the enable cPad™ function items 415 is operated on the pull-down menu 412 , it is possible to operate the screens (the changeover menu screen 431 , operation screen 432 ) to be operated by the cPad™ device 112 on the main display 121 .
[0059] In this case, a changeover operation screen display flag is set which is managed by the main CPU 201 and which is included in a cPad™ device management flag. Furthermore, items such as, but not limited to, “perform/not perform sound notification” and “change/not change pointer display” are opened under the enable cPad™ function items 415 . When settings are performed to “perform sound notification” or “change display of the pointer” on the items, a sound notification flag or a pointer display change flag included in the cPad™ device management flags are set. These cPad™ device management flags are not shown in the drawings.
[0060] The main CPU 201 accepts an event notice to change the screen of the cPad™ from the control program 302 of the cPad™ device 112 via the USB controller 210 (step S 21 ). In response to this notice, it is judged by the setting of the enable cPad™ function items 415 whether or not the sound notification flag is raised (set) (step S 22 ). When the sound notification flag is raised, the sound controller 106 is started, and it is notified that the screen of cPad™ is changed (step S 23 ). This notification may be given through any of a beep sound and sound message. When the notification by sound is unnecessary (obtrusive), the sound notification flag is set to “not perform sound notification”, and the notification by the sound may be invalidated.
[0061] Next, it is judged whether or not a changeover operation screen display flag is raised (set) in the setting of the enable cPad™ function items 415 (step S 24 ). When the changeover operation screen display flag is raised, a display area of the changeover menu screen 431 is secured in the vicinity of the mouse pointer (MC) displayed on the main display 121 (step S 25 ). Furthermore, the changeover menu screen 431 to be operated by the cPad™ device 112 is displayed in the secured area (step S 26 ).
[0062] Thereby, when visually checking the main display 121 and performing the touch operation, the operator can change the operation screen of the cPad™ device 112 without visually checking the cPad™ device 112 , and can smoothly and efficiently execute the touch operation. Moreover, for example, when the operation screen is changed by mistake on the cPad™ device 112 , the mistake can instantly be noticed, and destruction of the data by an erroneous cPad™ operation, input mistake, and/or wasted operations can securely be prevented.
[0063] Next, it is judged whether or not a pointer display change flag is raised (set) in the setting of the enable cPad™ function items 415 (step S 27 ). When the pointer display change flag is raised, the mouse pointer (MC) is changed to a pointer (TD) having, for example, the shape shown on the right side in FIG. 8 for a predetermined time, and the user is notified of the changeover of the cPad™ screen with the mouse pointer (step S 28 ).
[0064] When visually checking the main display 121 and performing the touch operation, the operator visually checks in the vicinity of the mouse pointer (MC) in many cases. Therefore, it can be recognized with high probability that the cPad™ screen has been changed (for example, the operation screen has been changed by mistake on the cPad™ device 112 ).
[0065] Moreover, as shown in FIG. 6, when the changeover menu screen 431 to be operated by the cPad™ device 112 is displayed on the main display 121 , the selection button of the operation screen to be operated (e.g., the selection button Ib of the calculator) is clicked in the selection buttons (icons) Ia, Ib, . . . of various operation screens on the changeover menu screen 431 (step S 29 ). In response to this click, instead of the changeover menu screen 431 , the operation screen 432 of the calculator is temporarily displayed as shown in FIG. 7 following the selection operation (steps S 30 , S 31 ). Thereby, the operation screen 432 subjected to a changeover operation (selected) is confirmed, and the visual observation on the main display 121 and the touch operation can be continued. For example, when the operation screen is changed by mistake on the cPad™ device 112 , the operation screen may be returned to the original, and the touch operation can be continued as such.
[0066] In this case, in addition to the confirmation of the operation screen 432 with the above-described changeover operation, the operation screen 432 is displayed continuously, not temporarily. After the operation ends on the operation screen. 432 , the operation screen 432 can also be deleted from the main display 121 . This function is realized, for example, by disposing selection item “operate/not operate operation screen 432 to be operated by cPad™ device 112 on main display 121 ” in the pull-down menu 412 .
[0067] Alternatively, this function can also be realized by: displaying the operation screen 432 continuously, not temporarily; and deleting the operation screen 432 from the main display 121 , when the operation ends on the operation screen 432 and there is a predetermined button operation (e.g., simultaneous operation of two buttons disposed in the cPad™ device 112 ).
[0068] A concrete operation procedure and state transition of the above-described cPad™ screen operation will be described with reference to FIGS. 11 and 12.
[0069] In this example, when the changeover operation screen display flag is raised (set) in the setting of the enable cPad™ function items 415 on the pull-down menu 412 described above, as shown in FIG. 11, the display of the cPad™ screen becomes valid on the main display 121 . Moreover, as shown in FIG. 12, when the middle button 113 c disposed in the cPad™ device 112 is depressed, the changeover menu screen displayed in the cPad™ device 112 , and the same changeover menu screen 431 are displayed in the vicinity of the mouse pointer (MC) on the main display 121 .
[0070] Moreover, when the changeover operation screen display flag is not raised (set), as shown in FIG. 11, the display of the cPad™ screen on the main display 121 becomes invalid. Even when the middle button 113 c disposed in the cPad™ device 112 is depressed, there is no change in the display of the main display 121 .
[0071] Moreover, when the changeover operation screen display flag is raised (set) in the setting of the enable cPad™ function items 415 on the above-described pull-down menu 412 , that is, when the display of the cPad™ screen becomes valid on the main display 121 as shown in FIG. 11, the sound notification flag and pointer display change flag, for example, are raised (set). In this case, when the changeover menu screen 431 is displayed as shown in FIG. 12, a cPad™ screen change is notified to the user by a sound (beep sound or sound message) and mouse pointer shape (or color, display mode) change. Thereby, when visually checking the main display 121 and performing the touch operation, the user can securely recognize the change of the cPad™ screen (for example, the operation screen has been changed by mistake on the cPad™ device 112 ) without visually checking the cPad™ device 112 .
[0072] Furthermore, in this case, when the changeover menu screen is tap-operated on the cPad™ device 112 , the changed operation screen can be displayed in the cPad™ device 112 . Moreover, when one of the selection buttons (icons) Ia, Ib, . . . is clicked in the changeover menu screen 431 on the main display 121 , the changed operation screen 432 can be displayed in the cPad™ device 112 .
[0073] In this case, when the cPad™ screen is changed, as shown in FIG. 12, the cPad™ screen change is notified to the user by the sound and the shape change of the mouse pointer. Subsequently, the operation screen 432 is displayed for the predetermined time for which the visual confirmation is possible, and subsequently deleted. Thereby, the operation screen 432 subjected to the changeover operation (selected) is confirmed, and the visual observation on the main display 121 and the touch operation can be continued. Moreover, when the operation screen is changed by mistake on the cPad™ device 112 , the user may return the operation screen to the original, and the touch operation can be continued as such.
[0074] Moreover, as shown in FIG. 12, in a state in which the changeover menu screen 431 is displayed, a predetermined button is depressed among three buttons disposed in the cPad™ device 112 . At this time, the changeover menu screen 431 displayed in the cPad™ device 112 and main display 121 is deleted, and the mouse pointer returns to its original shape.
[0075] As described above, it follows that according to the present embodiment a mechanism to confirm and change the cPad™ screen without visually checking the cPad™ device 112 is disposed, and thereby the erroneous operation can be prevented. Moreover, when the cPad™ screen is changed by the erroneous operation, the user may return the operation screen to the original without visually checking the cPad™ device 112 . Moreover, the changeover of the cPad™ screen can be permitted/prohibited without visually checking the cPad™ device 112 . In addition, the changeover of the cPad™ screen is displayed in the main display 121 , and can further be notified by outputting a sound. Therefore, the stage after the changeover of the cPad™ screen can securely be confirmed without visually checking the cPad™ device 112 . Moreover, without visually checking the cPad™ device 112 , the state of the screen display of the cPad™ device 112 can always be confirmed by the touch operation while visually checking the main display 121 . Therefore, the touch operation can smoothly and efficiently be executed.
[0076] It is to be noted that one example of each of the hardware and software constitutions of the computer, screen constitution, and operation procedure has been described in the above-described embodiment, and these are not specified in carrying out the present invention.
[0077] According to the present embodiment, there can be provided the computer system and operation method of the computer in which the erroneous operation is prevented in advance and touch operation can be smoothly performed in the constitution including two display devices to display the operation screen on each display device. | An information processing apparatus and method providing a main display for displaying a first operation screen used to perform a first operation and a sub-display separate from the main display for displaying a second operation screen used to perform a second operation. The sub-display is integral with a touch pad pointing device. A processor of the information processing apparatus is programmed to provide notification when the second operation screen is opened or changed. The notification may be selectively provided on the main display such that a user performing touch operation on the sub-display while viewing the main display is notified that the second operation screen has been opened or changed. The notification may be visual, audible or tactile. The second operation may be executed in parallel with the first operation or independently of the first operation. The first operation screen and the second operation screen may be simultaneously displayed. | 6 |
BACKGROUND OF THE INVENTION
This invention relates generally to heat transfer systems, and more particularly to a pump and heat exchanger assembly which is compact and easily maintained.
DESCRIPTION OF THE PRIOR ART
Typical heat exchanger systems for controlling the temperature of cooling water for various kinds of manufacturing machines employ fabricated tanks with heating and/or cooling coils in them and which are piped into a process water plumbing circuit including a pump, various valves and controls. The tanks involve a considerable amount of fabrication. Their combination with pumps and the associated plumbing also involves considerable labor, space demands, and the attendant problems of packaging into reasonably sized units, particularly where portability of the temperature controller assembly is desirable. There are also attendant maintenance problems.
SUMMARY OF THE INVENTION
Described briefly, according to a typical embodiment of the present invention, a combination pump and heat exchanger assembly is provided with the pump case serving as the mount for heat exchanger units and for the pump drive motor. The pump case has upwardly opening receptacles, one communicating with the impeller intake and the other with the impeller discharge. A tubular heat exchanger unit is mounted in each of the receptacles and is removably secured therein by threaded fasteners and sealed therein by compression seals. The heat exchanger units may employ electrical heaters or chilled liquid piping therein.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a symbolic diagram of a process cooling water circuit including the pump and heat exchanger assembly of the present invention therein.
FIG. 2 is an enlarged elevational view of the pump intake end of the pump and heat exchanger assembly.
FIG. 3 is an elevational view of the motor end of the pump case but omitting the motor, adaptor plate and pump impeller.
FIG. 4 is a small side elevational view of the pump and heat exchanger assembly with the upper portion of the heat exchangers eliminated to conserve space in the drawing, and showing the pump motor and adaptor mounted to the rear of the pump case.
FIG. 5 is a top plan view of the same scale as FIG. 4.
FIG. 6 is a rear end elevational view of a complete machine employing the pump and heat exchanger assembly of the present invention in an "open circuit" process water system.
FIG. 7 is a side elevational view thereof.
DESCRIPTION OF THE PREFERRED EMBODIMENT
For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiment 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.
Referring now to FIG. 1, the process equipment to be temperature-controlled as shown generally at 11. It may include injection molding machines, lasers, or other equipment requiring temperature control and in which water is usually used as the temperature controlling fluid. Water is supplied to the process through the line 12 and departs the process through the line 13 and enters the heat exchanger tube 14 through a spud opening 16 at the cylindrical wall thereof near the top. Tube 14 is received in an upwardly-opening receptacle 17 in the pump case 18 and which communicates through the passageway 19 to the pump intake on the axis 21 (FIGS. 4 and 5). The water is discharged through a similar upwardly opening receptacle 22 in which is received a tube 23. In the illustrated example, the process water is in a closed circuit. Therefore, a spud opening at 24 near the top of tube 23 is connected to the discharge line 12 supplying the process 11. Tubes 14 and 23 are heat exchanger tubes. In the illustrated example, the heat exchanger tube 14 is provided with means for cooling the water passing through it from the spud 16 into the pump case 18. The heat exchanger tube 23 is provided with means for heating the water discharged from the pump and departing through the spud 24. More specifically, a coiled tube 26 in heat exchanger tube 14 receives water through a valve 27 from a city water supply 28. This water moves upward in tube 25 an exits near the upper end of tube 26 and passes through a solenoid operated valve 29 which discharges to the sewer 31.
In the other heat exchanger tube 23, there is an electrical heating element 32 supplied by electrical power applied across the terminals 33.
The pump case 18 is generally circular about a horizontal axis 21 (FIGS. 4 and 5) lying in a vertical plane 34 (FIG. 2). The axis 21 is the axis of the volute 25 (FIG. 3) in which the impeller (not shown) resides and rotates. The tube receivers 17 and 22 are generally cylindrical as are the tubes 14 and 23, and their axes 36 and 37 lie in a vertical plane 38 (FIGS. 4 and 5) which is perpendicular to the pump axis 21 as the lower portion of each tube is inserted as at 39 in FIG. 2 for tube 23, into the tube receiver 22. The tube axes 36 and 37 are equally spaced from and on opposite sides of the plane 34.
A flange 41 is welded to the exterior of tube 23. It is apertured at the four corners and receives the stem of a cap screw 42 at each corner and which is screwed into the pump case at four corners of a square around the receptacle receiving the tue (FIG. 5). Exactly the same mounting is provided for tube 14 as shown for tube 23. Therefore, a description of the sealing of tube 14 will suffice also for tube 23. In this case, there is an upwardly opening cylindrical bore 43 in the receptacle 17 and which receives the tube 14 in a loose sliding fit. A radially inward extending shoulder 44 at the bottom of bore 43 receives and supports an elastomeric seal ring 45 of rectangular cross section therein. The lower end 46 of the tube 14 is disposed on top of the seal 45. It seals completely around the end of the tube when the cap screws 42 are screwed into the pump case at the four corners around the tube 14.
The rear of the pump case has a double flanged adaptor 47 secured to it by circularly spaced can screws (not shown) bearing on flange 47A. The pump drive motor 48 is secured to the adaptor by a series of circularly spaced cap screws (not shown) bearing on flange 47B. The pump case has a rectangular mounting base 51 with four bolt holes in the corners thereof as at 52 to receive bolts to mount it to a mounting pad in either a stationary unit or a mobile cabinet. This arrangement is sufficient to support the motor 48 without any brace at the outer end of the motor.
In FIG. 3, where the front of the pump case is shown with the motor and adaptor removed from it, the tap bolt holes 51 are shown in a circle of six. Additional tapped holes are shown at 53A and 53B for connection to input and output pressure gauges (not shown). A tapped hole 54 is provided for a pressure relief valve. The tapped hole 56 is provided for connection of a temperature sensor. The central opening 57 on the pump axis is shown cross-hatched to indicate shading, not a screen.
Referring now to FIGS. 6 and 7, there is shown an "open circuit" embodiment of the invention. In this case, instead of using a separate coil such as 26 for the cooling water, the cooling is achieved, when necessary, by discharging process water to drain and supplying fresh water from a public utility, for example, directly into the process water circuit. In this embodiment, the pump case may be exactly the same as in the previously described embodiment. It is shown with a slightly more specifically defined flange at the top of the pump case where the tube receiver receptacles are located. Hat exchanger tube 23 is identical and is mounted in an identical fashion with the cap screws 42. In this embodiment, the heat exchanger tube 23 at the intake site of the pump is identical to that at the pump discharge side. This enables doubling the heating capacity of the assembly without any change of dimension. If desired, of course, the tube at the intake side can be essentially identical to that at the output side but without the electrical heating element in it. In any case, the mounting is the same as previously described with reference to the first embodiment. In this instance however, the heat exchanger tube 23 at the pump input side and which receives the water from the process through line 13, has an outlet line 61 connected to a spud opening at the back of the tube 23 directly behind inlet opening 16 at the front. This line is connected through electrically controlled valve assembly 29 which is normally closed. The outlet side of the valve at 62 is at the rear of the machine for connection to a drain just as the valve 29 in the FIG. 1 embodiment discharges to a sewer. Make-up water from a city water supply as at 28 in FIG. 1, is supplied through input line 64 and electrically operated valve, if desired, at 66, and the supply line 67 into the threaded hole 68 at the bottom of the intake passageway of the pump case and which, in the closed circuit version of FIG. 1 has a plug 69 in it. The pump case drain opening is plugged with a plug 71 in this embodiment just as in the previous embodiment.
If it is desired to double the heating capacity of the unit, both of the heat exchanger tubes are identical and each may have a junction box 72 at the upper end thereof, both of which are connected as by a line 73 into the control cabinet 74. All of this apparatus is mounted on a base 76 which , in this embodiment, is mounted on four caster assemblies 77. As in the first described embodiment, the pump case itself provides the total support for the motor 48, without any additional support at the outer end of the motor, part of which is extending inside the cabinet 74 as best shown in FIG. 7. The cabinet may have a control panel 78 at the top front, and the two pressure gauges 79 and 81 in the top of the cabinet are readily observable to the operator. Theses may be connected as by pilot lines to the threaded ports 53A and 53B described above with reference to FIG. 3.
The pump case is cast iron. The heat exchanger tubes are steel. The whole unit is much small than others known to us for a given heating capacity. By using 9 KW heating elements in each tube, the machine can have 18 KW heating capacity using 3 inch diameter tubes about 14 inches long.
While the invention has 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. | A combination pump and heat exchanger assembly uses a cast metal pump case with two upwardly opening sockets receiving the lower ends of two tubes, one of them communicating through the case with the pump impeller intake and the other with the impeller discharge. The tubes are constructed to function as heat exchanger units and are removably secured to the case by threaded fasteners and are sealed therein by compression seals. The heat exchanger tubes may employ electrical heating units or chilled liquid piping units therein. | 5 |
FIELD OF THE INVENTION
[0001] The present invention relates to vehicle airbags, and more particularly to a vehicle side curtain airbag device with front protection function.
BACKGROUND OF THE INVENTION
[0002] At present, components and parts in conventional motor vehicle passive safety systems are used to mainly protect passengers in front seats. Besides safety belts, these components and parts include front airbags and side airbags. Generally, the front airbags and side airbags are inflated by gas generators to protect passengers. The as generators are ignited under the control of main control units, which presents good results and saves thousands of lives. Moreover, for protecting passengers in rear seats, most motor vehicles are equipped only with safety belts. However, safety belts can restrain the rear passengers' bodies, but they cannot protect the rear passengers' head and neck, so the rear passengers' head and neck are often injured by excessive stretching.
[0003] According to CNCAP Crash Test 2012 edition, that is, new car assessment program on rear passenger injuries 2012 edition, in a total of eighteen kinds of tested vehicles, only two kinds of vehicles get full marks for protecting rear passengers' heads and necks in frontal impact test against rigid barrier, with 100% overlapping at 50 km/h and frontal impact test against deformable barrier with 40% overlapping at 64 km/h. Even some CNCAP five-star vehicles scores 0 in protecting rear passengers' heads and necks.
[0004] According to 2012 Insurance Institute for Highway Safety (IIHS) 25% rigid barrier offset impact test results, most of vehicles cannot reach the level of excellence in the evaluation of occupant restraint because occupants' heads slide out of drivers' airbag protection range.
SUMMARY OF THE INVENTION
[0005] An object of the present invention is to overcome the foregoing problems and dispose a transverse additional airbag on a side airbag to protect a passenger' head and neck effectively.
[0006] To achieve the above-mentioned object, a vehicle side curtain airbag device having front protective function in accordance with the present invention is provided. The vehicle side curtain airbag device includes a side airbag, wherein one side face of the side airbag is connected to an end face of an additional airbag which is in a left-right transverse arrangement after being inflated.
[0007] The additional airbag has an inflation inlet defined outside an end face of the additional airbag; or an inflation hole is formed through an end face of the additional airbag and the side airbag; or a connecting portion between an end face of the additional airbag and the side airbag is formed integrally and a diffluence hole membrane is formed on an end face of the additional airbag, wherein a periphery of the diffluence hole membrane is surrounded by that of the end face of the additional airbag.
[0008] The additional airbag has no vent hole or at least one vent hole defined therein. The additional airbag is located in front of an area where a passenger in a seat sits
[0009] An outer contour of the additional airbag is generally a transverse cylinder after the additional airbag is inflated; or the outer contour of the additional airbag is generally a triangular body in the shape of sandwich after the additional airbag is inflated; or the outer contour of the additional airbag has a generally wedge-shaped cross-section after the additional airbag is inflated.
[0010] When the outer contour of the inflated additional airbag has a generally wedge-shaped cross-section, an angle between an inflation direction of the inflated additional airbag and a longitudinal direction (i.e. the front-rear direction) of a vehicle body is between 45 degrees and 90 degrees.
[0011] A free end of the additional airbag is connected to one end of as bulling strap, and the other end of the pulling strap is fixed on a vehicle body ceiling.
[0012] At least one additional airbag is connected to the side airbag.
[0013] The diffluence hole membrane has a plurality of seam lines sewn thereon, which are for tearing and parallel to each other, an outer profile defined by the plurality of seam lines has a geometric shape, and the diffluence hole membrane with the plurality of seam lines is stacked or folded.
[0014] Comparing with the prior state of the art, the present invention provides not only protection for passengers' heads and necks in side collisions, but also protection for front and rear passengers' heads and necks in frontal collisions. Further, the present invention may dispose the diffluence hole membrane between the side airbag and the additional airbag and ensure that the diffluence hole membrane isn't broken through until an internal pressure of the side airbag reaches a certain value, thus the present invention can achieve adaptive adjustment of the opening threshold, control the point in time, the length of time and the rate for charging the additional airbag, and adjust the stiffness of the additional airbag, which ensures that the present invention can absorb impact energy that is applied to passengers more effectively and further reduce damage to passengers.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a work schematic view of a conventional side curtain, after being inflated;
[0016] FIG. 2 is a work schematic view of an additional airbag with a diffluence hole membrane and a side airbag according to an embodiment of the present invention, after being inflated;
[0017] FIG. 3 is a work schematic view of an additional airbag with an inflation inlet and a side airbag according to an embodiment of the present invention, after being inflated;
[0018] FIG. 4 is a work schematic view of an additional airbag with an inflation hole and a side airbag according to an embodiment of the present invention, after being inflated;
[0019] FIG. 5 is a work schematic view of a side airbag connected with two additional airbags according to an embodiment of the present invention;
[0020] FIG. 6 is a side view of additional airbags with pulling straps according to an embodiment of the present invention, in a work state;
[0021] FIG. 7 is a top view of the additional airbags with pulling straps according to an embodiment of the present invention, in the work state;
[0022] FIG. 8 is a side view of sandwich-shaped additional airbags according to an embodiment of the present invention, in a work state;
[0023] FIG. 9 is a top view of the sandwich-shaped additional airbags according to an embodiment of the present invention, in the work state;
[0024] FIG. 10 is a side view of wedge-shaped additional airbags according to an embodiment of the present invention, in a work state;
[0025] FIG. 11 is a top view of the wedge-shaped additional airbags according to an embodiment of the present invention, in the work state;
[0026] FIG. 12 is a curve diagram of passengers' head acceleration after a frontal impact, wherein a vehicle side curtain airbag device of a first embodiment of the present invention and a conventional side curtain airbag device are respectively used;
[0027] FIG. 13 is a curve diagram of shearing forces on passengers' necks of a frontal impact, wherein the vehicle side curtain airbag device of the first embodiment of the present invention and a conventional side curtain airbag device are respectively used;
[0028] FIG. 14 is a curve diagram of stretching forces on passengers' necks of a frontal impact, wherein the vehicle side curtain airbag device of the first embodiment of the present invention and a conventional side curtain airbag device are respectively used; and
[0029] FIG. 15 is a curve diagram of neck bending moments after a frontal impact, wherein the vehicle side curtain airbag device of the first embodiment of the present invention and a conventional side curtain airbag device are respectively used.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0030] Below the present invention is described in detail on the basis of the accompanying drawings and embodiments.
[0031] The present invention provides a vehicle side curtain airbag device which can provide a front protection for passengers, or “vehicle side curtain airbag device” for short in the embodiment. The vehicle side curtain airbag device has an airbag portion which mainly includes a side airbag and an additional airbag. Like conventional vehicle side curtain airbag devices, the vehicle side curtain airbag device of the present invention may be fixed between one side of a vehicle body ceiling 7 and a vehicle body interior ceiling, and the side airbag 1 is long enough to cover passengers from a first row to a last row. A gas generator for inflating the side airbag 1 and the additional airbag 2 is fixed between the vehicle body ceiling 7 and the vehicle body interior ceiling. According to the requirement of internal pressure of the side airbag 1 , one or more than one gas generators may be disposed. A main control unit for the vehicle side curtain airbag device may be installed in a vehicle body center tunnel, close to front passengers. The main control unit includes a plurality of sensors arranged around the vehicle body to detect side or frontal impact, thereby ensuring that the side airbag and the additional airbag are inflated in time.
[0032] A major characteristic of the present invention is that one side of the side airbag 1 , that is the user side of the side airbag 1 , is connected to one end face of the additional airbag 2 which is in a left-right transverse arrangement after being inflated, and at least one additional airbag 2 is connected to the side airbag 1 , wherein the number or the transverse length of the additional airbags 2 is determined by the passenger-capacity of the vehicle.
[0033] The additional airbag 2 may have an inflation inlet 31 defined outside an end face thereof, as shown in FIG. 3 , so that when a collision occurs, the main control unit may inflate only the side airbag 1 or both the side airbag 1 and the additional airbag 2 through two paths according to the impact force. Alternatively, an inflation hole 32 is formed through an end face of the additional airbag 2 and the side airbag 1 , as shown in FIG. 4 , so that when a collision occurs, the additional airbag 2 and the side airbag 1 may be inflated at the same time. In another embodiment, a connecting portion between an end face of the additional airbag 2 and the side airbag 1 is formed integrally and a diffluence hole membrane 3 is formed on an end face of the additional airbag 2 , a periphery of the diffluence hole membrane 3 surrounded by that of the end face of the additional airbag as shown in FIG. 2 . A plurality of seam lines, parallel to each other, are sewn on the diffluence hole membrane 3 and used for tearing. An outer profile defined by the plurality of seam lines has a geometric shape. The diffluence hole membrane 3 with the plurality of seam lines is stacked or folded. In this way, the main control unit of the vehicle side curtain airbag device can control the rate of inflation at which the gas generator inflates the side airbag and the volume of inflated gas according to the impact force so as to ensure that the diffluence hole membrane 3 isn't broken through and the additional airbag 2 doesn't work, or the diffluence hole membrane 3 is broken through and the side airbag 1 and the additional airbag 2 are inflated one after another.
[0034] The additional airbag 2 may have no hollow through-hole or at least one hollow through-hole 5 defined therein. When there is one hollow through-hole 5 defined in the additional airbag 2 , the additional airbag 2 is ring shaped. The cross section of the through-hole 5 may be triangular, circular and so on. The through-hole 5 may be arranged up-down vertically; alternatively, the through-hole 5 may also be arranged left-right horizontally, as shown in FIG. 8 and FIG. 9 .
[0035] The additional airbag 2 is located in front of the area where a passenger in the seat 6 stays.
[0036] In one embodiment, an outer contour of the additional airbag 2 is generally a transverse cylinder after the additional airbag 2 is inflated. In another embodiment, the outer contour of the additional airbag 2 is generally a triangular body in the shape of sandwich after the additional airbag 2 is inflated. In another embodiment, the outer contour of the additional airbag 2 has a generally wedge-shaped cross-section after the additional airbag 2 is inflated.
[0037] When the outer contour of the inflated additional airbag 2 has a generally wedge-shaped cross-section, the angle between the inflation direction of the additional airbag 2 and the longitudinal direction of the vehicle body is between 45 degrees and 90 degrees, and in general, the angle can be 45 degrees or 60 degrees. A free end of the additional airbag 2 may be connected to one end of a pulling strap 4 , and the other end of the pulling strap 4 is fixed on the vehicle body ceiling 7 .
Embodiment 1
[0038] Please refer to FIG. 2 , in the first embodiment, the connecting portion between an end face of the additional airbag 2 and the side airbag 1 is formed integrally, that is the end face of the additional airbag 2 and the side airbag 1 share as layer of fabric at the connecting potion, and a diffluence hole membrane 3 is formed on an end face of the additional airbag 2 . Once a collision occurs, sensors around the vehicle body will transmit an impact force to the main control unit of the vehicle side curtain airbag device firstly. Then the main control unit controls the rate and the time of the gas generator inflating the side airbag based on the impact force, if the impact force is less than a given value of impact three for opening the additional airbag 2 , then the main control unit will control the gas generator to charge a certain amount of gas into the side airbag 1 and the side airbag 1 will expand downwards along interiors on the side of the vehicle body, but the charged gas cannot provide enough pressure for breaking through the diffluence hole membrane 3 . If the impact force reaches the given value of impact force liar opening the additional airbag 2 , then the main control unit will control the gas generator to charge enough gas into the side airbag 1 till the seam lines on the diffluence hole membrane 3 tears. At this time, the gas enters the additional airbag 2 so that the additional airbag 2 expands transversely. In the embodiment, the angle between the expansion direction of the additional airbag 2 and that of the side airbag 1 is about 90 degrees.
[0039] The diffluence hole membrane 3 can be regarded as an adaptive vent. When the pressure on the diffluence bole membrane 3 reaches an open value, the diffluence hole membrane 3 will be broken through. The main control unit can control the point in time, the length of time and the rate for charging the additional airbag 2 based on the impact force to adjust the stiffness of the additional airbag 2 , thereby more effectively absorbing impact energy that is applied to passengers and further reducing damage to passengers.
[0040] Please refer to FIGS. 12-15 , FIGS. 12-15 show the simulation of damage to passengers' heads and necks when frontal impact of vehicles occurs, wherein the vehicles are equipped with the airbag portion of the embodiment of the present invention which mainly includes the side airbag and the additional airbag. In FIGS. 12-15 , black solid lines indicate simulation curves of damage to passengers' heads and necks during frontal impact when conventional side curtains are applied in vehicles; and black broken lines indicate simulation curves of damage to passengers' heads and necks during frontal impact when the present invention is applied in vehicles. Comparing and analyzing the simulation results, it can be seen that the present invention can effectively absorb the impact energy in impact accidents and provide effective protection for front and rear passengers' heads and necks.
Embodiment 2
[0041] Please refer to FIG. 5 , the number of the additional airbags 2 connected to the side airbag 1 may be determined by the number of seats 6 in a vehicle. In the second embodiment, two additional airbags 2 in a front-rear arrangement are disposed on one side of the side airbag 1 . After being inflated, the two additional airbags 2 are located in front of front and rear passengers' heads, respectively. Each of the two inflated additional airbags 2 is shaped like a transverse cylinder of which the cross-section is oval. Once frontal impact occurs, the front and rear additional airbags 2 start to be inflated immediately after the side airbag 1 is inflated, and the inflated additional airbags 2 are located in front of the passengers' heads to protect their heads and necks. Taking younger passengers into consideration, the longitudinal length of the additional airbags 2 is prolonged appropriately. The front and rear additional airbags 2 can protect passengers not only in frontal impact accidents but also in angled offset impact accidents, for example, IIHS 25% rigid barrier offset impact test.
Embodiment 3
[0042] Please refer to FIG. 6 and FIG. 7 , the third embodiment is further improved on the basis of the second embodiment, that is, for providing enough support for avoiding that the additional airbags 2 move away from passengers, each of the two additional airbags 2 has a pulling strap 4 disposed thereon, of which one end is fastened on the is end of the corresponding additional airbag 2 and the other end is fixed between the vehicle body ceiling 7 and the interior ceiling. The constraining force of the additional airbags 2 can be optimized by adjusting the lengths of the pulling straps so as to reduce the acceleration of passengers' heads, thereby keeping passengers' heads from contacting with the seats 6 and/or an instrument panel and reducing neck injury risks.
Embodiment 4
[0043] Please refer to FIG. 8 and FIG. 9 , in the fourth embodiment, after being inflated, each additional airbag 2 has an outer contour of a triangular body which is generally in the shape of sandwich, and a triangular through-hole 5 is defined in a longitudinal direction in the middle of each additional airbag 2 . Alternatively, the through-hole may also he a circular hole so that the middle portion of the additional airbag 2 is hollow, so the additional airbag 2 provides not only an enough constraining force for passengers' heads, but also a certain buffer effect to avoid that the constraining force is too large to bring passengers' heads and necks a secondary damage.
Embodiment 5
[0044] Please refer to FIG. 10 and FIG. 11 the fifth embodiment also has two additional airbags 2 in a front-rear arrangement, After being inflated, each additional airbag 2 generally has an outer contour with a wedge-shaped horizontal cross-section, and the angle between the inflation direction of each additional airbag 2 and the longitudinal direction of the vehicle body is between 45 degrees and 90 degrees, and in general, the angle can be 45 degrees or 60 degrees, so that the free end of the additional airbag 2 inclines to the passenger side. The expansion shape of the additional airbags 2 can help increase the constraining force for passengers in the front-rear direction of the vehicle body and reduce the forwards movement of passengers' heads, thereby reducing neck injuries. | A vehicle side curtain airbag device having front protection function, comprising a side airbag ( 1 ) and an auxiliary airbag ( 2 ) connected to one side surface of the side airbag ( 1 ) and arranged in a left/right transverse direction after being expanded; a dividing hole membrane ( 3 ) is disposed between the side airbag ( 1 ) and the auxiliary airbag ( 2 ); the dividing hole membrane ( 3 ) is ensured to he opened only when the internal pressure of the side airbag ( 1 ) reaches a certain value, thus realizing self-adaptive opening threshold adjustment, controlling the instant of inflation and inflation speed of the auxiliary airbag ( 2 ), and adjusting the stiffness of the auxiliary airbag ( 2 ). When a vehicle has a collision, the device protects the head and neck of a passenger in both side collision and front collision traffic accidents, thus effectively absorbing the collision impact energy of the passenger, and reducing injury to the passenger. | 1 |
This application claims priority of U.S. Provisional patent application No. 61/690,446 filed Jun. 26, 2012.
FIELD OF INVENTION
The present invention relates to the field of utensil organizers, and more particularly pertains to a basket which holds and organizes utensils in a dishwasher and when removed from the dishwasher transforms into a basket which holds and organizes utensils in a kitchen cabinet drawer.
BACKGROUND OF THE INVENTION
Utensils used for eating are generally stored in a basket or a tray in the drawer of a kitchen cabinet utensil use, and then after use, unless they are washed by hand, they are placed in a separate basket in an automatic dishwasher which holds and organizes the utensils for cleaning. The clean utensils are removed from the dishwasher, sorted and generally placed into a basket or tray in the drawer of a kitchen cabinet. This is a repetitive and time-consuming chore. It can also be unsanitary, as it is necessary to touch each and every utensil.
An improved device is needed which eliminates much of this repetitive work, a device which eliminates a step in this process and which maintains the utensils in an organized and useful arrangement and is also inexpensive and simple to manufacture and easy to use.
SUMMARY OF INVENTION
It is therefore an object of the present invention to provide a new and improved device which eliminates the need to empty the eating utensils from the utensil basket or tray taken out of a dishwasher, and is also inexpensive and simple to manufacture and easy to use.
It is a further object of the present invention to provide a new and improved device which eliminates the need to empty the utensil basket or tray in a dishwasher, simply transforming that basket or tray into a drawer organizer and placing it into a drawer.
It is further object of the present invention to provide a new and improved device which eliminates the need to empty the utensil basket or tray in a dishwasher, simply transforming that basket or tray into a drawer organizer and pacing it into a drawer with the sanitary advantage. That it is not necessary to touch each and every utensil when moving it from the dishwasher to a drawer.
It is a further object of the present invention to provide a new and improved device which eliminates the need to empty the utensil basket or tray in a dishwasher, simply transforming that basket or tray into a drawer organizer and placing it into a drawer, said basket or tray being manufactured of compatible size and material to be compatible with the baskets or trays provided by commonly available dishwasher manufactures.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and other features of the present invention will be more readily apparent from the following description of the preferred embodiment taken in conjunction with the attached drawings, wherein:
FIG. 1 is a perspective oblique side view of a household dishwasher utensil basket according to one embodiment of the present invention, showing said invention configured for a dishwasher.
FIG. 2 is a perspective front view of a household dishwasher utensil basket according to one embodiment of the present invention, showing said invention configured for a dishwasher.
FIG. 3 is a perspective edge view of a household dishwasher utensil basket according to one embodiment of the present invention, showing said invention configured for a dishwasher.
FIG. 4 is a perspective top oblique's view of a household dishwasher utensil basket according to one embodiment of the present invention, showing said invention configured for a dishwasher.
FIG. 5 is a perspective edge view of a household dishwasher utensil basket according to one embodiment of the present invention, showing said invention with front panel 111 folded open.
FIG. 6 is a perspective edge view of a household dishwasher utensil basket according to one embodiment of the present invention, showing said invention with front panel 111 folded under the household dishwasher utensil basket 140 .
FIG. 7 is a perspective edge view of a household dishwasher utensil basket according to one embodiment of the present invention, showing said invention configured as a drawer insert, with front panel 111 folded under the household dishwasher utensil basket 140 .
FIG. 8 is a perspective oblique side view of a household dishwasher utensil basket according to one embodiment of the present invention, showing said invention configured as a drawer insert, with front panel 111 folded under the household dishwasher utensil basket 140 .
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the figures, FIG. 1 shows the present invention, household dishwasher utensil basket 140 according to one embodiment of said invention comprising a rear wall 100 , side walls 102 , a front wall 111 , a bottom wall 103 and interior panels 104 dividing the basket into compartments for the purpose of holding, organizing and separating eating utensils such as silverware, comprising knives, forks, spoons and the like.
The structure of said front wall 111 includes hinge means 122 , 123 , 124 , 125 , 126 , 132 , 133 , 134 , and 135 which allow said front wall 111 to fold forward and under said dishwasher utensil basket 140 , permitting said dishwasher utensil basket 140 to be re-configured and inserted into a drawer without the necessary of removing and sorting said utensils. A clip means 141 holds front wall 111 securely in place when household dishwasher utensil basket 140 is configured for dishwasher use. Hook means 145 and 147 serve as an additional or as an alternative means of removably fastening front wall 111 securely in place.
Referring to FIG. 2 , household dishwasher utensil basket 140 is shown according to one embodiment of said invention comprising a rear wall 100 , side walls 102 , a front wall 111 and interior panels 104 dividing the basket into compartments for the purpose of holding, organizing, and separating eating utensils such as silverware, comprising knives, forks, spoons and the like.
The structure of said front wall 111 includes hinge means 122 , 123 , 124 , 125 , 126 , 131 , 132 , 133 , 134 and 135 which allow said front wall 111 to fold forward and under said dishwasher utensil basket 140 , permitting said dishwasher utensil basket 140 to be re-configured and inserted into a drawer without the necessity of removing and sorting said utensils. A clip means 141 holds said front wall 111 securely in place when household dishwasher utensil basket 140 is configured for dishwasher use. Hook means 145 and 147 serve as an additional or as an alternative means of removably fastening front wall 111 securely in place.
Referring to FIG. 3 , household dishwasher utensil basket 140 is shown according to one embodiment of said invention comprising a rear wall 100 , side walls 102 , a front wall 111 and interior panels 104 dividing the basket into compartments for the purpose of holding, organizing and separating eating utensils such as silverware, comprising knives, forks, spoons and the like;
The structure of said front wall 111 includes hinge means 122 , 123 , 124 , 125 , 126 , 132 , 133 , 134 and 135 which allow said front wall 111 to fold forward and under aid dishwasher utensil basket 140 , permitting said dishwasher utensil basket 140 to be re-configured and inserted into a drawer without the necessity of removing and sorting said utensils. Referring to FIG. 4 the front panel 111 is folded completely under said utensil basket, which when resting on its rear panel becomes a utensil drawer organizer. A clip means 141 holds said front wall 111 securely in place when household dishwasher utensil basket 140 is configured for dishwasher use. Hook means 145 and 147 serve as an additional or as an alternative means of removably fastening front wall 111 securely in place.
Referring to FIG. 5 , household dishwasher utensil basket 140 is viewed from the side, with clip means 141 released to allow front panel 111 to fold forward on hinge means 121 , in the process of transforming to a utensil drawer organizer. Hook means 145 and 147 serve as an additional or as an alternative means of fastening front wall 111 securely in place, and said hook means are shown here in an unhooked position.
Referring to FIG. 6 , household dishwasher utensil basket 140 is viewed from the side, with clip means 141 released to allow front panel 111 to fold forward almost completely on hinge means 121 , in the process of transforming to a utensil drawer organizer. Hook means 145 and 147 serve as an additional or as an alternative means of removably fastening front wall 111 securely in place, and said hook means are shown here in an unhooked position.
Referring to FIG. 7 , household dishwasher utensil basket 140 is viewed from the side, with clip means 141 released to allow front panel 111 to fold forward completely on hinge means 121 , transforming said utensil basket into a utensil drawer organizer. Hook means 145 and 147 serve as an additional or as an alternative means of removable fastening front wall 111 securely in place, and said hook means are shown here in an unhooked position.
Referring to FIG. 8 , household dishwasher utensil basket 140 is viewed obliquely from the side, clip means 141 released to allow with front panel 111 to fold forward completely on hinge means 121 , said front panel 111 being flexible as a result of incorporated hinge means 131 , 132 , 133 , 134 and 135 , transforming said utensil basket into a utensil drawer organizer. Hook means 145 and 147 serve as an additional or as an alternative means to clip means 141 of removably fastening front wall 111 securely in place, and said hook means are shown here in an unhooked position.
While the invention has been specifically described in connection with certain specific embodiments thereof, it is to be understood that this is by way of illustration and not of limitation, and the scope of the present invention should be constructed as broadly as the prior art will permit. | The invention relates to a new and improved dishwasher utensil basket which eliminates the need to empty the utensil basket or tray in a dishwasher, simply transforming that basket or tray into a drawer organizer and placing it into a drawer. This removable utensil basket saves time and effort and is more sanitary as it eliminates the need to touch each and every utensil. It is also inexpensive and simple to manufacture and easy to use. | 1 |
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